* [PATCH 1/9] mm: Provide new get_vaddr_frames() helper
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() Mauro Carvalho Chehab
` (10 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Kirill A. Shutemov, Konstantin Khlebnikov, Johannes Weiner,
Joonsoo Kim, Naoya Horiguchi, Cyrill Gorcunov,
Christian Borntraeger, Andrea Arcangeli, Hans Verkuil,
Paul Cassella, Steve Capper, Aneesh Kumar K.V, linux-mm,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Provide new function get_vaddr_frames(). This function maps virtual
addresses from given start and fills given array with page frame numbers of
the corresponding pages. If given start belongs to a normal vma, the function
grabs reference to each of the pages to pin them in memory. If start
belongs to VM_IO | VM_PFNMAP vma, we don't touch page structures. Caller
must make sure pfns aren't reused for anything else while he is using
them.
This function is created for various drivers to simplify handling of
their buffers.
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0755b9fd03a7..dcd1f02a78e9 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -20,6 +20,7 @@
#include <linux/shrinker.h>
#include <linux/resource.h>
#include <linux/page_ext.h>
+#include <linux/err.h>
struct mempolicy;
struct anon_vma;
@@ -1197,6 +1198,49 @@ long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
int write, int force, struct page **pages);
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
struct page **pages);
+
+/* Container for pinned pfns / pages */
+struct frame_vector {
+ unsigned int nr_allocated; /* Number of frames we have space for */
+ unsigned int nr_frames; /* Number of frames stored in ptrs array */
+ bool got_ref; /* Did we pin pages by getting page ref? */
+ bool is_pfns; /* Does array contain pages or pfns? */
+ void *ptrs[0]; /* Array of pinned pfns / pages. Use
+ * pfns_vector_pages() or pfns_vector_pfns()
+ * for access */
+};
+
+struct frame_vector *frame_vector_create(unsigned int nr_frames);
+void frame_vector_destroy(struct frame_vector *vec);
+int get_vaddr_frames(unsigned long start, unsigned int nr_pfns,
+ bool write, bool force, struct frame_vector *vec);
+void put_vaddr_frames(struct frame_vector *vec);
+int frame_vector_to_pages(struct frame_vector *vec);
+void frame_vector_to_pfns(struct frame_vector *vec);
+
+static inline unsigned int frame_vector_count(struct frame_vector *vec)
+{
+ return vec->nr_frames;
+}
+
+static inline struct page **frame_vector_pages(struct frame_vector *vec)
+{
+ if (vec->is_pfns) {
+ int err = frame_vector_to_pages(vec);
+
+ if (err)
+ return ERR_PTR(err);
+ }
+ return (struct page **)(vec->ptrs);
+}
+
+static inline unsigned long *frame_vector_pfns(struct frame_vector *vec)
+{
+ if (!vec->is_pfns)
+ frame_vector_to_pfns(vec);
+ return (unsigned long *)(vec->ptrs);
+}
+
struct kvec;
int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
struct page **pages);
diff --git a/mm/gup.c b/mm/gup.c
index 6297f6bccfb1..9d7f4fde30cb 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -8,6 +8,7 @@
#include <linux/rmap.h>
#include <linux/swap.h>
#include <linux/swapops.h>
+#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/rwsem.h>
@@ -936,6 +937,231 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
return ret; /* 0 or negative error code */
}
+/*
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @write: whether pages will be written to by the caller
+ * @force: whether to force write access even if user mapping is
+ * readonly. See description of the same argument of
+ get_user_pages().
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_sem as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ bool write, bool force, struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+ int locked;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ down_read(&mm->mmap_sem);
+ locked = 1;
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ ret = get_user_pages_locked(current, mm, start, nr_frames,
+ write, force, (struct page **)(vec->ptrs), &locked);
+ goto out;
+ }
+
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /*
+ * We stop if we have enough pages or if VMA doesn't completely
+ * cover the tail page.
+ */
+ if (ret >= nr_frames || start < vma->vm_end)
+ break;
+ vma = find_vma_intersection(mm, start, start + 1);
+ } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+out:
+ if (locked)
+ up_read(&mm->mmap_sem);
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ int i;
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+ for (i = 0; i < vec->nr_frames; i++)
+ put_page(pages[i]);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ if (size <= PAGE_SIZE)
+ vec = kmalloc(size, GFP_KERNEL);
+ else
+ vec = vmalloc(size);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ if (!is_vmalloc_addr(vec))
+ kfree(vec);
+ else
+ vfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
+
/**
* get_dump_page() - pin user page in memory while writing it to core dump
* @addr: user address
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 1/9] mm: Provide new get_vaddr_frames() helper
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
0 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Kirill A. Shutemov, Konstantin Khlebnikov, Johannes Weiner,
Joonsoo Kim, Naoya Horiguchi, Cyrill Gorcunov,
Christian Borntraeger, Andrea Arcangeli, Hans Verkuil,
Paul Cassella, Steve Capper, Aneesh Kumar K.V, linux-mm,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Provide new function get_vaddr_frames(). This function maps virtual
addresses from given start and fills given array with page frame numbers of
the corresponding pages. If given start belongs to a normal vma, the function
grabs reference to each of the pages to pin them in memory. If start
belongs to VM_IO | VM_PFNMAP vma, we don't touch page structures. Caller
must make sure pfns aren't reused for anything else while he is using
them.
This function is created for various drivers to simplify handling of
their buffers.
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0755b9fd03a7..dcd1f02a78e9 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -20,6 +20,7 @@
#include <linux/shrinker.h>
#include <linux/resource.h>
#include <linux/page_ext.h>
+#include <linux/err.h>
struct mempolicy;
struct anon_vma;
@@ -1197,6 +1198,49 @@ long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
int write, int force, struct page **pages);
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
struct page **pages);
+
+/* Container for pinned pfns / pages */
+struct frame_vector {
+ unsigned int nr_allocated; /* Number of frames we have space for */
+ unsigned int nr_frames; /* Number of frames stored in ptrs array */
+ bool got_ref; /* Did we pin pages by getting page ref? */
+ bool is_pfns; /* Does array contain pages or pfns? */
+ void *ptrs[0]; /* Array of pinned pfns / pages. Use
+ * pfns_vector_pages() or pfns_vector_pfns()
+ * for access */
+};
+
+struct frame_vector *frame_vector_create(unsigned int nr_frames);
+void frame_vector_destroy(struct frame_vector *vec);
+int get_vaddr_frames(unsigned long start, unsigned int nr_pfns,
+ bool write, bool force, struct frame_vector *vec);
+void put_vaddr_frames(struct frame_vector *vec);
+int frame_vector_to_pages(struct frame_vector *vec);
+void frame_vector_to_pfns(struct frame_vector *vec);
+
+static inline unsigned int frame_vector_count(struct frame_vector *vec)
+{
+ return vec->nr_frames;
+}
+
+static inline struct page **frame_vector_pages(struct frame_vector *vec)
+{
+ if (vec->is_pfns) {
+ int err = frame_vector_to_pages(vec);
+
+ if (err)
+ return ERR_PTR(err);
+ }
+ return (struct page **)(vec->ptrs);
+}
+
+static inline unsigned long *frame_vector_pfns(struct frame_vector *vec)
+{
+ if (!vec->is_pfns)
+ frame_vector_to_pfns(vec);
+ return (unsigned long *)(vec->ptrs);
+}
+
struct kvec;
int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
struct page **pages);
diff --git a/mm/gup.c b/mm/gup.c
index 6297f6bccfb1..9d7f4fde30cb 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -8,6 +8,7 @@
#include <linux/rmap.h>
#include <linux/swap.h>
#include <linux/swapops.h>
+#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/rwsem.h>
@@ -936,6 +937,231 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
return ret; /* 0 or negative error code */
}
+/*
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @write: whether pages will be written to by the caller
+ * @force: whether to force write access even if user mapping is
+ * readonly. See description of the same argument of
+ get_user_pages().
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_sem as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ bool write, bool force, struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+ int locked;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ down_read(&mm->mmap_sem);
+ locked = 1;
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ ret = get_user_pages_locked(current, mm, start, nr_frames,
+ write, force, (struct page **)(vec->ptrs), &locked);
+ goto out;
+ }
+
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /*
+ * We stop if we have enough pages or if VMA doesn't completely
+ * cover the tail page.
+ */
+ if (ret >= nr_frames || start < vma->vm_end)
+ break;
+ vma = find_vma_intersection(mm, start, start + 1);
+ } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+out:
+ if (locked)
+ up_read(&mm->mmap_sem);
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ int i;
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+ for (i = 0; i < vec->nr_frames; i++)
+ put_page(pages[i]);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ if (size <= PAGE_SIZE)
+ vec = kmalloc(size, GFP_KERNEL);
+ else
+ vec = vmalloc(size);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ if (!is_vmalloc_addr(vec))
+ kfree(vec);
+ else
+ vfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
+
/**
* get_dump_page() - pin user page in memory while writing it to core dump
* @addr: user address
--
2.4.2
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^ permalink raw reply related [flat|nested] 35+ messages in thread* Re: [PATCH 1/9] mm: Provide new get_vaddr_frames() helper
2015-06-10 9:20 ` Mauro Carvalho Chehab
@ 2015-06-11 8:01 ` Sergey Senozhatsky
-1 siblings, 0 replies; 35+ messages in thread
From: Sergey Senozhatsky @ 2015-06-11 8:01 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Kirill A. Shutemov, Konstantin Khlebnikov,
Johannes Weiner, Joonsoo Kim, Naoya Horiguchi, Cyrill Gorcunov,
Christian Borntraeger, Andrea Arcangeli, Hans Verkuil,
Paul Cassella, Steve Capper, Aneesh Kumar K.V, linux-mm
On (06/10/15 06:20), Mauro Carvalho Chehab wrote:
[..]
> +
> +/**
> + * frame_vector_destroy() - free memory allocated to carry frame vector
> + * @vec: Frame vector to free
> + *
> + * Free structure allocated by frame_vector_create() to carry frames.
> + */
> +void frame_vector_destroy(struct frame_vector *vec)
> +{
> + /* Make sure put_vaddr_frames() got called properly... */
> + VM_BUG_ON(vec->nr_frames > 0);
> + if (!is_vmalloc_addr(vec))
> + kfree(vec);
> + else
> + vfree(vec);
minor: kvfree(vec);
-ss
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 1/9] mm: Provide new get_vaddr_frames() helper
@ 2015-06-11 8:01 ` Sergey Senozhatsky
0 siblings, 0 replies; 35+ messages in thread
From: Sergey Senozhatsky @ 2015-06-11 8:01 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Kirill A. Shutemov, Konstantin Khlebnikov,
Johannes Weiner, Joonsoo Kim, Naoya Horiguchi, Cyrill Gorcunov,
Christian Borntraeger, Andrea Arcangeli, Hans Verkuil,
Paul Cassella, Steve Capper, Aneesh Kumar K.V, linux-mm
On (06/10/15 06:20), Mauro Carvalho Chehab wrote:
[..]
> +
> +/**
> + * frame_vector_destroy() - free memory allocated to carry frame vector
> + * @vec: Frame vector to free
> + *
> + * Free structure allocated by frame_vector_create() to carry frames.
> + */
> +void frame_vector_destroy(struct frame_vector *vec)
> +{
> + /* Make sure put_vaddr_frames() got called properly... */
> + VM_BUG_ON(vec->nr_frames > 0);
> + if (!is_vmalloc_addr(vec))
> + kfree(vec);
> + else
> + vfree(vec);
minor: kvfree(vec);
-ss
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
^ permalink raw reply [flat|nested] 35+ messages in thread
* [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
2015-06-10 9:20 ` Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-11 4:21 ` Laurent Pinchart
2015-06-10 9:20 ` [PATCH 3/9] [media] vb2: Provide helpers for mapping virtual addresses Mauro Carvalho Chehab
` (9 subsequent siblings)
11 siblings, 1 reply; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Hans Verkuil, Fabian Frederick, Prabhakar Lad, Laurent Pinchart,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() instead of
hand made mapping of virtual address to physical address. Also the
function leaked page reference from get_user_pages() so fix that by
properly release the reference when omap_vout_buffer_release() is
called.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
[hans.verkuil@cisco.com: remove unused struct omap_vout_device *vout variable]
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/platform/omap/omap_vout.c b/drivers/media/platform/omap/omap_vout.c
index f09c5f17a42f..7feb6394f111 100644
--- a/drivers/media/platform/omap/omap_vout.c
+++ b/drivers/media/platform/omap/omap_vout.c
@@ -195,46 +195,34 @@ static int omap_vout_try_format(struct v4l2_pix_format *pix)
}
/*
- * omap_vout_uservirt_to_phys: This inline function is used to convert user
- * space virtual address to physical address.
+ * omap_vout_get_userptr: Convert user space virtual address to physical
+ * address.
*/
-static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp)
+static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp,
+ u32 *physp)
{
- unsigned long physp = 0;
- struct vm_area_struct *vma;
- struct mm_struct *mm = current->mm;
+ struct frame_vector *vec;
+ int ret;
/* For kernel direct-mapped memory, take the easy way */
- if (virtp >= PAGE_OFFSET)
- return virt_to_phys((void *) virtp);
-
- down_read(¤t->mm->mmap_sem);
- vma = find_vma(mm, virtp);
- if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) {
- /* this will catch, kernel-allocated, mmaped-to-usermode
- addresses */
- physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start);
- up_read(¤t->mm->mmap_sem);
- } else {
- /* otherwise, use get_user_pages() for general userland pages */
- int res, nr_pages = 1;
- struct page *pages;
+ if (virtp >= PAGE_OFFSET) {
+ *physp = virt_to_phys((void *)virtp);
+ return 0;
+ }
- res = get_user_pages(current, current->mm, virtp, nr_pages, 1,
- 0, &pages, NULL);
- up_read(¤t->mm->mmap_sem);
+ vec = frame_vector_create(1);
+ if (!vec)
+ return -ENOMEM;
- if (res == nr_pages) {
- physp = __pa(page_address(&pages[0]) +
- (virtp & ~PAGE_MASK));
- } else {
- printk(KERN_WARNING VOUT_NAME
- "get_user_pages failed\n");
- return 0;
- }
+ ret = get_vaddr_frames(virtp, 1, true, false, vec);
+ if (ret != 1) {
+ frame_vector_destroy(vec);
+ return -EINVAL;
}
+ *physp = __pfn_to_phys(frame_vector_pfns(vec)[0]);
+ vb->priv = vec;
- return physp;
+ return 0;
}
/*
@@ -784,11 +772,15 @@ static int omap_vout_buffer_prepare(struct videobuf_queue *q,
* address of the buffer
*/
if (V4L2_MEMORY_USERPTR == vb->memory) {
+ int ret;
+
if (0 == vb->baddr)
return -EINVAL;
/* Physical address */
- vout->queued_buf_addr[vb->i] = (u8 *)
- omap_vout_uservirt_to_phys(vb->baddr);
+ ret = omap_vout_get_userptr(vb, vb->baddr,
+ (u32 *)&vout->queued_buf_addr[vb->i]);
+ if (ret < 0)
+ return ret;
} else {
unsigned long addr, dma_addr;
unsigned long size;
@@ -834,12 +826,13 @@ static void omap_vout_buffer_queue(struct videobuf_queue *q,
static void omap_vout_buffer_release(struct videobuf_queue *q,
struct videobuf_buffer *vb)
{
- struct omap_vout_device *vout = q->priv_data;
-
vb->state = VIDEOBUF_NEEDS_INIT;
+ if (vb->memory == V4L2_MEMORY_USERPTR && vb->priv) {
+ struct frame_vector *vec = vb->priv;
- if (V4L2_MEMORY_MMAP != vout->memory)
- return;
+ put_vaddr_frames(vec);
+ frame_vector_destroy(vec);
+ }
}
/*
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* Re: [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
2015-06-10 9:20 ` [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() Mauro Carvalho Chehab
@ 2015-06-11 4:21 ` Laurent Pinchart
2015-06-11 17:23 ` Hans Verkuil
2015-06-12 9:21 ` Tomi Valkeinen
0 siblings, 2 replies; 35+ messages in thread
From: Laurent Pinchart @ 2015-06-11 4:21 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Hans Verkuil, Fabian Frederick,
Prabhakar Lad, Tomi Valkeinen
Hello,
(CC'ing Tomi Valkeinen)
On Wednesday 10 June 2015 06:20:45 Mauro Carvalho Chehab wrote:
> From: Jan Kara <jack@suse.cz>
>
> Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() instead of
> hand made mapping of virtual address to physical address. Also the
> function leaked page reference from get_user_pages() so fix that by
> properly release the reference when omap_vout_buffer_release() is
> called.
>
> Signed-off-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> [hans.verkuil@cisco.com: remove unused struct omap_vout_device *vout
> variable]
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>
> diff --git a/drivers/media/platform/omap/omap_vout.c
> b/drivers/media/platform/omap/omap_vout.c index f09c5f17a42f..7feb6394f111
> 100644
> --- a/drivers/media/platform/omap/omap_vout.c
> +++ b/drivers/media/platform/omap/omap_vout.c
> @@ -195,46 +195,34 @@ static int omap_vout_try_format(struct v4l2_pix_format
> *pix) }
>
> /*
> - * omap_vout_uservirt_to_phys: This inline function is used to convert user
> - * space virtual address to physical address.
> + * omap_vout_get_userptr: Convert user space virtual address to physical
> + * address.
> */
> -static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp)
> +static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp,
> + u32 *physp)
> {
> - unsigned long physp = 0;
> - struct vm_area_struct *vma;
> - struct mm_struct *mm = current->mm;
> + struct frame_vector *vec;
> + int ret;
>
> /* For kernel direct-mapped memory, take the easy way */
> - if (virtp >= PAGE_OFFSET)
> - return virt_to_phys((void *) virtp);
> -
> - down_read(¤t->mm->mmap_sem);
> - vma = find_vma(mm, virtp);
> - if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) {
> - /* this will catch, kernel-allocated, mmaped-to-usermode
> - addresses */
> - physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start);
> - up_read(¤t->mm->mmap_sem);
> - } else {
> - /* otherwise, use get_user_pages() for general userland pages */
> - int res, nr_pages = 1;
> - struct page *pages;
> + if (virtp >= PAGE_OFFSET) {
> + *physp = virt_to_phys((void *)virtp);
Lovely. virtp comes from userspace and as far as I know it arrives here
completely unchecked. The problem isn't introduced by this patch, but
omap_vout buffer management seems completely broken to me, and nobody seems to
care about the driver. Given that omapdrm should now provide the video output
capabilities that are missing from omapfb and resulted in the development of
omap_vout, shouldn't we drop the omap_vout driver ?
Tomi, any opinion on this ? Do you see any omap_vout capability missing from
omapdrm ?
> + return 0;
> + }
>
> - res = get_user_pages(current, current->mm, virtp, nr_pages, 1,
> - 0, &pages, NULL);
> - up_read(¤t->mm->mmap_sem);
> + vec = frame_vector_create(1);
> + if (!vec)
> + return -ENOMEM;
>
> - if (res == nr_pages) {
> - physp = __pa(page_address(&pages[0]) +
> - (virtp & ~PAGE_MASK));
> - } else {
> - printk(KERN_WARNING VOUT_NAME
> - "get_user_pages failed\n");
> - return 0;
> - }
> + ret = get_vaddr_frames(virtp, 1, true, false, vec);
> + if (ret != 1) {
> + frame_vector_destroy(vec);
> + return -EINVAL;
> }
> + *physp = __pfn_to_phys(frame_vector_pfns(vec)[0]);
> + vb->priv = vec;
>
> - return physp;
> + return 0;
> }
>
> /*
> @@ -784,11 +772,15 @@ static int omap_vout_buffer_prepare(struct
> videobuf_queue *q, * address of the buffer
> */
> if (V4L2_MEMORY_USERPTR == vb->memory) {
> + int ret;
> +
> if (0 == vb->baddr)
> return -EINVAL;
> /* Physical address */
> - vout->queued_buf_addr[vb->i] = (u8 *)
> - omap_vout_uservirt_to_phys(vb->baddr);
> + ret = omap_vout_get_userptr(vb, vb->baddr,
> + (u32 *)&vout->queued_buf_addr[vb->i]);
> + if (ret < 0)
> + return ret;
> } else {
> unsigned long addr, dma_addr;
> unsigned long size;
> @@ -834,12 +826,13 @@ static void omap_vout_buffer_queue(struct
> videobuf_queue *q, static void omap_vout_buffer_release(struct
> videobuf_queue *q,
> struct videobuf_buffer *vb)
> {
> - struct omap_vout_device *vout = q->priv_data;
> -
> vb->state = VIDEOBUF_NEEDS_INIT;
> + if (vb->memory == V4L2_MEMORY_USERPTR && vb->priv) {
> + struct frame_vector *vec = vb->priv;
>
> - if (V4L2_MEMORY_MMAP != vout->memory)
> - return;
> + put_vaddr_frames(vec);
> + frame_vector_destroy(vec);
> + }
> }
>
> /*
--
Regards,
Laurent Pinchart
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
2015-06-11 4:21 ` Laurent Pinchart
@ 2015-06-11 17:23 ` Hans Verkuil
2015-06-12 9:21 ` Tomi Valkeinen
1 sibling, 0 replies; 35+ messages in thread
From: Hans Verkuil @ 2015-06-11 17:23 UTC (permalink / raw)
To: Laurent Pinchart, Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Hans Verkuil, Fabian Frederick,
Prabhakar Lad, Tomi Valkeinen
On 06/11/15 06:21, Laurent Pinchart wrote:
> Hello,
>
> (CC'ing Tomi Valkeinen)
>
> On Wednesday 10 June 2015 06:20:45 Mauro Carvalho Chehab wrote:
>> From: Jan Kara <jack@suse.cz>
>>
>> Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() instead of
>> hand made mapping of virtual address to physical address. Also the
>> function leaked page reference from get_user_pages() so fix that by
>> properly release the reference when omap_vout_buffer_release() is
>> called.
>>
>> Signed-off-by: Jan Kara <jack@suse.cz>
>> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
>> [hans.verkuil@cisco.com: remove unused struct omap_vout_device *vout
>> variable]
>>
>> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>>
>> diff --git a/drivers/media/platform/omap/omap_vout.c
>> b/drivers/media/platform/omap/omap_vout.c index f09c5f17a42f..7feb6394f111
>> 100644
>> --- a/drivers/media/platform/omap/omap_vout.c
>> +++ b/drivers/media/platform/omap/omap_vout.c
>> @@ -195,46 +195,34 @@ static int omap_vout_try_format(struct v4l2_pix_format
>> *pix) }
>>
>> /*
>> - * omap_vout_uservirt_to_phys: This inline function is used to convert user
>> - * space virtual address to physical address.
>> + * omap_vout_get_userptr: Convert user space virtual address to physical
>> + * address.
>> */
>> -static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp)
>> +static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp,
>> + u32 *physp)
>> {
>> - unsigned long physp = 0;
>> - struct vm_area_struct *vma;
>> - struct mm_struct *mm = current->mm;
>> + struct frame_vector *vec;
>> + int ret;
>>
>> /* For kernel direct-mapped memory, take the easy way */
>> - if (virtp >= PAGE_OFFSET)
>> - return virt_to_phys((void *) virtp);
>> -
>> - down_read(¤t->mm->mmap_sem);
>> - vma = find_vma(mm, virtp);
>> - if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) {
>> - /* this will catch, kernel-allocated, mmaped-to-usermode
>> - addresses */
>> - physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start);
>> - up_read(¤t->mm->mmap_sem);
>> - } else {
>> - /* otherwise, use get_user_pages() for general userland pages */
>> - int res, nr_pages = 1;
>> - struct page *pages;
>> + if (virtp >= PAGE_OFFSET) {
>> + *physp = virt_to_phys((void *)virtp);
>
> Lovely. virtp comes from userspace and as far as I know it arrives here
> completely unchecked. The problem isn't introduced by this patch, but
> omap_vout buffer management seems completely broken to me, and nobody seems to
> care about the driver. Given that omapdrm should now provide the video output
> capabilities that are missing from omapfb and resulted in the development of
> omap_vout, shouldn't we drop the omap_vout driver ?
In addition it uses the old videobuf framework which at some point will be reason
for removal if nobody cares enough to convert to videobuf2.
So I would also be in favor of removal if there are no objections (well, probably
first to staging for one or two kernel cycles followed by removal).
Hans
>
> Tomi, any opinion on this ? Do you see any omap_vout capability missing from
> omapdrm ?
>
>> + return 0;
>> + }
>>
>> - res = get_user_pages(current, current->mm, virtp, nr_pages, 1,
>> - 0, &pages, NULL);
>> - up_read(¤t->mm->mmap_sem);
>> + vec = frame_vector_create(1);
>> + if (!vec)
>> + return -ENOMEM;
>>
>> - if (res == nr_pages) {
>> - physp = __pa(page_address(&pages[0]) +
>> - (virtp & ~PAGE_MASK));
>> - } else {
>> - printk(KERN_WARNING VOUT_NAME
>> - "get_user_pages failed\n");
>> - return 0;
>> - }
>> + ret = get_vaddr_frames(virtp, 1, true, false, vec);
>> + if (ret != 1) {
>> + frame_vector_destroy(vec);
>> + return -EINVAL;
>> }
>> + *physp = __pfn_to_phys(frame_vector_pfns(vec)[0]);
>> + vb->priv = vec;
>>
>> - return physp;
>> + return 0;
>> }
>>
>> /*
>> @@ -784,11 +772,15 @@ static int omap_vout_buffer_prepare(struct
>> videobuf_queue *q, * address of the buffer
>> */
>> if (V4L2_MEMORY_USERPTR == vb->memory) {
>> + int ret;
>> +
>> if (0 == vb->baddr)
>> return -EINVAL;
>> /* Physical address */
>> - vout->queued_buf_addr[vb->i] = (u8 *)
>> - omap_vout_uservirt_to_phys(vb->baddr);
>> + ret = omap_vout_get_userptr(vb, vb->baddr,
>> + (u32 *)&vout->queued_buf_addr[vb->i]);
>> + if (ret < 0)
>> + return ret;
>> } else {
>> unsigned long addr, dma_addr;
>> unsigned long size;
>> @@ -834,12 +826,13 @@ static void omap_vout_buffer_queue(struct
>> videobuf_queue *q, static void omap_vout_buffer_release(struct
>> videobuf_queue *q,
>> struct videobuf_buffer *vb)
>> {
>> - struct omap_vout_device *vout = q->priv_data;
>> -
>> vb->state = VIDEOBUF_NEEDS_INIT;
>> + if (vb->memory == V4L2_MEMORY_USERPTR && vb->priv) {
>> + struct frame_vector *vec = vb->priv;
>>
>> - if (V4L2_MEMORY_MMAP != vout->memory)
>> - return;
>> + put_vaddr_frames(vec);
>> + frame_vector_destroy(vec);
>> + }
>> }
>>
>> /*
>
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
2015-06-11 4:21 ` Laurent Pinchart
2015-06-11 17:23 ` Hans Verkuil
@ 2015-06-12 9:21 ` Tomi Valkeinen
2015-06-12 9:26 ` Laurent Pinchart
1 sibling, 1 reply; 35+ messages in thread
From: Tomi Valkeinen @ 2015-06-12 9:21 UTC (permalink / raw)
To: Laurent Pinchart, Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Hans Verkuil, Fabian Frederick,
Prabhakar Lad
[-- Attachment #1: Type: text/plain, Size: 3270 bytes --]
On 11/06/15 07:21, Laurent Pinchart wrote:
> Hello,
>
> (CC'ing Tomi Valkeinen)
>
> On Wednesday 10 June 2015 06:20:45 Mauro Carvalho Chehab wrote:
>> From: Jan Kara <jack@suse.cz>
>>
>> Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() instead of
>> hand made mapping of virtual address to physical address. Also the
>> function leaked page reference from get_user_pages() so fix that by
>> properly release the reference when omap_vout_buffer_release() is
>> called.
>>
>> Signed-off-by: Jan Kara <jack@suse.cz>
>> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
>> [hans.verkuil@cisco.com: remove unused struct omap_vout_device *vout
>> variable]
>>
>> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>>
>> diff --git a/drivers/media/platform/omap/omap_vout.c
>> b/drivers/media/platform/omap/omap_vout.c index f09c5f17a42f..7feb6394f111
>> 100644
>> --- a/drivers/media/platform/omap/omap_vout.c
>> +++ b/drivers/media/platform/omap/omap_vout.c
>> @@ -195,46 +195,34 @@ static int omap_vout_try_format(struct v4l2_pix_format
>> *pix) }
>>
>> /*
>> - * omap_vout_uservirt_to_phys: This inline function is used to convert user
>> - * space virtual address to physical address.
>> + * omap_vout_get_userptr: Convert user space virtual address to physical
>> + * address.
>> */
>> -static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp)
>> +static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp,
>> + u32 *physp)
>> {
>> - unsigned long physp = 0;
>> - struct vm_area_struct *vma;
>> - struct mm_struct *mm = current->mm;
>> + struct frame_vector *vec;
>> + int ret;
>>
>> /* For kernel direct-mapped memory, take the easy way */
>> - if (virtp >= PAGE_OFFSET)
>> - return virt_to_phys((void *) virtp);
>> -
>> - down_read(¤t->mm->mmap_sem);
>> - vma = find_vma(mm, virtp);
>> - if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) {
>> - /* this will catch, kernel-allocated, mmaped-to-usermode
>> - addresses */
>> - physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start);
>> - up_read(¤t->mm->mmap_sem);
>> - } else {
>> - /* otherwise, use get_user_pages() for general userland pages */
>> - int res, nr_pages = 1;
>> - struct page *pages;
>> + if (virtp >= PAGE_OFFSET) {
>> + *physp = virt_to_phys((void *)virtp);
>
> Lovely. virtp comes from userspace and as far as I know it arrives here
> completely unchecked. The problem isn't introduced by this patch, but
> omap_vout buffer management seems completely broken to me, and nobody seems to
> care about the driver. Given that omapdrm should now provide the video output
> capabilities that are missing from omapfb and resulted in the development of
> omap_vout, shouldn't we drop the omap_vout driver ?
>
> Tomi, any opinion on this ? Do you see any omap_vout capability missing from
> omapdrm ?
I've never used omap_vout, so I don't even know what it offers. I do
know it supports VRFB rotation (omap3), which we don't have on omapdrm,
though. Whether anyone uses that (or omap_vout), I have no idea...
I'd personally love to get rid of omap_vout, as it causes complications
on omapfb/omapdss side.
Tomi
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^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
2015-06-12 9:21 ` Tomi Valkeinen
@ 2015-06-12 9:26 ` Laurent Pinchart
2015-06-12 9:44 ` Tomi Valkeinen
0 siblings, 1 reply; 35+ messages in thread
From: Laurent Pinchart @ 2015-06-12 9:26 UTC (permalink / raw)
To: Tomi Valkeinen
Cc: Mauro Carvalho Chehab, Andrew Morton, Jan Kara,
Linux Media Mailing List, Mauro Carvalho Chehab, Hans Verkuil,
Fabian Frederick, Prabhakar Lad
[-- Attachment #1: Type: text/plain, Size: 3581 bytes --]
Hi Tomi,
On Friday 12 June 2015 12:21:13 Tomi Valkeinen wrote:
> On 11/06/15 07:21, Laurent Pinchart wrote:
> > On Wednesday 10 June 2015 06:20:45 Mauro Carvalho Chehab wrote:
> >> From: Jan Kara <jack@suse.cz>
> >>
> >> Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() instead of
> >> hand made mapping of virtual address to physical address. Also the
> >> function leaked page reference from get_user_pages() so fix that by
> >> properly release the reference when omap_vout_buffer_release() is
> >> called.
> >>
> >> Signed-off-by: Jan Kara <jack@suse.cz>
> >> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> >> [hans.verkuil@cisco.com: remove unused struct omap_vout_device *vout
> >> variable]
> >>
> >> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
> >>
> >> diff --git a/drivers/media/platform/omap/omap_vout.c
> >> b/drivers/media/platform/omap/omap_vout.c index
> >> f09c5f17a42f..7feb6394f111
> >> 100644
> >> --- a/drivers/media/platform/omap/omap_vout.c
> >> +++ b/drivers/media/platform/omap/omap_vout.c
> >> @@ -195,46 +195,34 @@ static int omap_vout_try_format(struct
> >> v4l2_pix_format *pix) }
> >>
> >> /*
> >>
> >> - * omap_vout_uservirt_to_phys: This inline function is used to convert
> >> user - * space virtual address to physical address.
> >> + * omap_vout_get_userptr: Convert user space virtual address to physical
> >> + * address.
> >>
> >> */
> >>
> >> -static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp)
> >> +static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp,
> >> + u32 *physp)
> >>
> >> {
> >>
> >> - unsigned long physp = 0;
> >> - struct vm_area_struct *vma;
> >> - struct mm_struct *mm = current->mm;
> >> + struct frame_vector *vec;
> >> + int ret;
> >>
> >> /* For kernel direct-mapped memory, take the easy way */
> >>
> >> - if (virtp >= PAGE_OFFSET)
> >> - return virt_to_phys((void *) virtp);
> >> -
> >> - down_read(¤t->mm->mmap_sem);
> >> - vma = find_vma(mm, virtp);
> >> - if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) {
> >> - /* this will catch, kernel-allocated, mmaped-to-usermode
> >> - addresses */
> >> - physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start);
> >> - up_read(¤t->mm->mmap_sem);
> >> - } else {
> >> - /* otherwise, use get_user_pages() for general userland pages */
> >> - int res, nr_pages = 1;
> >> - struct page *pages;
> >> + if (virtp >= PAGE_OFFSET) {
> >> + *physp = virt_to_phys((void *)virtp);
> >
> > Lovely. virtp comes from userspace and as far as I know it arrives here
> > completely unchecked. The problem isn't introduced by this patch, but
> > omap_vout buffer management seems completely broken to me, and nobody
> > seems to care about the driver. Given that omapdrm should now provide the
> > video output capabilities that are missing from omapfb and resulted in
> > the development of omap_vout, shouldn't we drop the omap_vout driver ?
> >
> > Tomi, any opinion on this ? Do you see any omap_vout capability missing
> > from omapdrm ?
>
> I've never used omap_vout, so I don't even know what it offers. I do
> know it supports VRFB rotation (omap3), which we don't have on omapdrm,
> though. Whether anyone uses that (or omap_vout), I have no idea...
>
> I'd personally love to get rid of omap_vout, as it causes complications
> on omapfb/omapdss side.
How difficult would it be to implement VRFB rotation in omapdrm ?
--
Regards,
Laurent Pinchart
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^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
2015-06-12 9:26 ` Laurent Pinchart
@ 2015-06-12 9:44 ` Tomi Valkeinen
0 siblings, 0 replies; 35+ messages in thread
From: Tomi Valkeinen @ 2015-06-12 9:44 UTC (permalink / raw)
To: Laurent Pinchart
Cc: Mauro Carvalho Chehab, Andrew Morton, Jan Kara,
Linux Media Mailing List, Mauro Carvalho Chehab, Hans Verkuil,
Fabian Frederick, Prabhakar Lad
[-- Attachment #1: Type: text/plain, Size: 3924 bytes --]
On 12/06/15 12:26, Laurent Pinchart wrote:
> Hi Tomi,
>
> On Friday 12 June 2015 12:21:13 Tomi Valkeinen wrote:
>> On 11/06/15 07:21, Laurent Pinchart wrote:
>>> On Wednesday 10 June 2015 06:20:45 Mauro Carvalho Chehab wrote:
>>>> From: Jan Kara <jack@suse.cz>
>>>>
>>>> Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() instead of
>>>> hand made mapping of virtual address to physical address. Also the
>>>> function leaked page reference from get_user_pages() so fix that by
>>>> properly release the reference when omap_vout_buffer_release() is
>>>> called.
>>>>
>>>> Signed-off-by: Jan Kara <jack@suse.cz>
>>>> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
>>>> [hans.verkuil@cisco.com: remove unused struct omap_vout_device *vout
>>>> variable]
>>>>
>>>> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>>>>
>>>> diff --git a/drivers/media/platform/omap/omap_vout.c
>>>> b/drivers/media/platform/omap/omap_vout.c index
>>>> f09c5f17a42f..7feb6394f111
>>>> 100644
>>>> --- a/drivers/media/platform/omap/omap_vout.c
>>>> +++ b/drivers/media/platform/omap/omap_vout.c
>>>> @@ -195,46 +195,34 @@ static int omap_vout_try_format(struct
>>>> v4l2_pix_format *pix) }
>>>>
>>>> /*
>>>>
>>>> - * omap_vout_uservirt_to_phys: This inline function is used to convert
>>>> user - * space virtual address to physical address.
>>>> + * omap_vout_get_userptr: Convert user space virtual address to physical
>>>> + * address.
>>>>
>>>> */
>>>>
>>>> -static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp)
>>>> +static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp,
>>>> + u32 *physp)
>>>>
>>>> {
>>>>
>>>> - unsigned long physp = 0;
>>>> - struct vm_area_struct *vma;
>>>> - struct mm_struct *mm = current->mm;
>>>> + struct frame_vector *vec;
>>>> + int ret;
>>>>
>>>> /* For kernel direct-mapped memory, take the easy way */
>>>>
>>>> - if (virtp >= PAGE_OFFSET)
>>>> - return virt_to_phys((void *) virtp);
>>>> -
>>>> - down_read(¤t->mm->mmap_sem);
>>>> - vma = find_vma(mm, virtp);
>>>> - if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) {
>>>> - /* this will catch, kernel-allocated, mmaped-to-usermode
>>>> - addresses */
>>>> - physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start);
>>>> - up_read(¤t->mm->mmap_sem);
>>>> - } else {
>>>> - /* otherwise, use get_user_pages() for general userland pages */
>>>> - int res, nr_pages = 1;
>>>> - struct page *pages;
>>>> + if (virtp >= PAGE_OFFSET) {
>>>> + *physp = virt_to_phys((void *)virtp);
>>>
>>> Lovely. virtp comes from userspace and as far as I know it arrives here
>>> completely unchecked. The problem isn't introduced by this patch, but
>>> omap_vout buffer management seems completely broken to me, and nobody
>>> seems to care about the driver. Given that omapdrm should now provide the
>>> video output capabilities that are missing from omapfb and resulted in
>>> the development of omap_vout, shouldn't we drop the omap_vout driver ?
>>>
>>> Tomi, any opinion on this ? Do you see any omap_vout capability missing
>>> from omapdrm ?
>>
>> I've never used omap_vout, so I don't even know what it offers. I do
>> know it supports VRFB rotation (omap3), which we don't have on omapdrm,
>> though. Whether anyone uses that (or omap_vout), I have no idea...
>>
>> I'd personally love to get rid of omap_vout, as it causes complications
>> on omapfb/omapdss side.
>
> How difficult would it be to implement VRFB rotation in omapdrm ?
I don't know... drivers/video/fbdev/omap2/vrfb.c contains the code to
handle the VRFB hardware, but it does require certain amount of book
keeping and tweaking of the fb size etc from the omapdrm side. And
probably a new parameter to somehow enable vrfb for a buffer, as you
don't want it to be used by default.
Tomi
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^ permalink raw reply [flat|nested] 35+ messages in thread
* [PATCH 3/9] [media] vb2: Provide helpers for mapping virtual addresses
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 4/9] [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector Mauro Carvalho Chehab
` (8 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Pawel Osciak, Marek Szyprowski, Kyungmin Park, Hans Verkuil,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Provide simple helper functions to map virtual address range into an
array of pfns / pages.
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/v4l2-core/videobuf2-memops.c b/drivers/media/v4l2-core/videobuf2-memops.c
index 81c1ad8b2cf1..0ec186d41b9b 100644
--- a/drivers/media/v4l2-core/videobuf2-memops.c
+++ b/drivers/media/v4l2-core/videobuf2-memops.c
@@ -137,6 +137,64 @@ int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size,
EXPORT_SYMBOL_GPL(vb2_get_contig_userptr);
/**
+ * vb2_create_framevec() - map virtual addresses to pfns
+ * @start: Virtual user address where we start mapping
+ * @length: Length of a range to map
+ * @write: Should we map for writing into the area
+ *
+ * This function allocates and fills in a vector with pfns corresponding to
+ * virtual address range passed in arguments. If pfns have corresponding pages,
+ * page references are also grabbed to pin pages in memory. The function
+ * returns pointer to the vector on success and error pointer in case of
+ * failure. Returned vector needs to be freed via vb2_destroy_pfnvec().
+ */
+struct frame_vector *vb2_create_framevec(unsigned long start,
+ unsigned long length,
+ bool write)
+{
+ int ret;
+ unsigned long first, last;
+ unsigned long nr;
+ struct frame_vector *vec;
+
+ first = start >> PAGE_SHIFT;
+ last = (start + length - 1) >> PAGE_SHIFT;
+ nr = last - first + 1;
+ vec = frame_vector_create(nr);
+ if (!vec)
+ return ERR_PTR(-ENOMEM);
+ ret = get_vaddr_frames(start, nr, write, 1, vec);
+ if (ret < 0)
+ goto out_destroy;
+ /* We accept only complete set of PFNs */
+ if (ret != nr) {
+ ret = -EFAULT;
+ goto out_release;
+ }
+ return vec;
+out_release:
+ put_vaddr_frames(vec);
+out_destroy:
+ frame_vector_destroy(vec);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(vb2_create_framevec);
+
+/**
+ * vb2_destroy_framevec() - release vector of mapped pfns
+ * @vec: vector of pfns / pages to release
+ *
+ * This releases references to all pages in the vector @vec (if corresponding
+ * pfns are backed by pages) and frees the passed vector.
+ */
+void vb2_destroy_framevec(struct frame_vector *vec)
+{
+ put_vaddr_frames(vec);
+ frame_vector_destroy(vec);
+}
+EXPORT_SYMBOL(vb2_destroy_framevec);
+
+/**
* vb2_common_vm_open() - increase refcount of the vma
* @vma: virtual memory region for the mapping
*
diff --git a/include/media/videobuf2-memops.h b/include/media/videobuf2-memops.h
index f05444ca8c0c..2f0564ff5f31 100644
--- a/include/media/videobuf2-memops.h
+++ b/include/media/videobuf2-memops.h
@@ -15,6 +15,7 @@
#define _MEDIA_VIDEOBUF2_MEMOPS_H
#include <media/videobuf2-core.h>
+#include <linux/mm.h>
/**
* vb2_vmarea_handler - common vma refcount tracking handler
@@ -36,5 +37,9 @@ int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size,
struct vm_area_struct *vb2_get_vma(struct vm_area_struct *vma);
void vb2_put_vma(struct vm_area_struct *vma);
+struct frame_vector *vb2_create_framevec(unsigned long start,
+ unsigned long length,
+ bool write);
+void vb2_destroy_framevec(struct frame_vector *vec);
#endif
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 4/9] [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (2 preceding siblings ...)
2015-06-10 9:20 ` [PATCH 3/9] [media] vb2: Provide helpers for mapping virtual addresses Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 5/9] [media] media: vb2: Convert vb2_vmalloc_get_userptr() " Mauro Carvalho Chehab
` (7 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Pawel Osciak, Marek Szyprowski, Kyungmin Park, Hans Verkuil,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Simplify the VMA code by using frame_vector_pages() & friends on VB2.
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index d7bcb05c7058..be7bd6535c9d 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -38,6 +38,7 @@ struct vb2_dma_sg_buf {
struct device *dev;
void *vaddr;
struct page **pages;
+ struct frame_vector *vec;
int offset;
enum dma_data_direction dma_dir;
struct sg_table sg_table;
@@ -51,7 +52,6 @@ struct vb2_dma_sg_buf {
unsigned int num_pages;
atomic_t refcount;
struct vb2_vmarea_handler handler;
- struct vm_area_struct *vma;
struct dma_buf_attachment *db_attach;
};
@@ -225,25 +225,17 @@ static void vb2_dma_sg_finish(void *buf_priv)
dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
}
-static inline int vma_is_io(struct vm_area_struct *vma)
-{
- return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
-}
-
static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
unsigned long size,
enum dma_data_direction dma_dir)
{
struct vb2_dma_sg_conf *conf = alloc_ctx;
struct vb2_dma_sg_buf *buf;
- unsigned long first, last;
- int num_pages_from_user;
- struct vm_area_struct *vma;
struct sg_table *sgt;
DEFINE_DMA_ATTRS(attrs);
+ struct frame_vector *vec;
dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
-
buf = kzalloc(sizeof *buf, GFP_KERNEL);
if (!buf)
return NULL;
@@ -254,63 +246,19 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
buf->offset = vaddr & ~PAGE_MASK;
buf->size = size;
buf->dma_sgt = &buf->sg_table;
-
- first = (vaddr & PAGE_MASK) >> PAGE_SHIFT;
- last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
- buf->num_pages = last - first + 1;
-
- buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
- GFP_KERNEL);
- if (!buf->pages)
- goto userptr_fail_alloc_pages;
-
- down_read(¤t->mm->mmap_sem);
- vma = find_vma(current->mm, vaddr);
- if (!vma) {
- dprintk(1, "no vma for address %lu\n", vaddr);
- goto userptr_fail_find_vma;
- }
-
- if (vma->vm_end < vaddr + size) {
- dprintk(1, "vma at %lu is too small for %lu bytes\n",
- vaddr, size);
- goto userptr_fail_find_vma;
- }
-
- buf->vma = vb2_get_vma(vma);
- if (!buf->vma) {
- dprintk(1, "failed to copy vma\n");
- goto userptr_fail_find_vma;
- }
-
- if (vma_is_io(buf->vma)) {
- for (num_pages_from_user = 0;
- num_pages_from_user < buf->num_pages;
- ++num_pages_from_user, vaddr += PAGE_SIZE) {
- unsigned long pfn;
-
- if (follow_pfn(vma, vaddr, &pfn)) {
- dprintk(1, "no page for address %lu\n", vaddr);
- break;
- }
- buf->pages[num_pages_from_user] = pfn_to_page(pfn);
- }
- } else
- num_pages_from_user = get_user_pages(current, current->mm,
- vaddr & PAGE_MASK,
- buf->num_pages,
- buf->dma_dir == DMA_FROM_DEVICE,
- 1, /* force */
- buf->pages,
- NULL);
- up_read(¤t->mm->mmap_sem);
-
- if (num_pages_from_user != buf->num_pages)
- goto userptr_fail_get_user_pages;
+ vec = vb2_create_framevec(vaddr, size, buf->dma_dir == DMA_FROM_DEVICE);
+ if (IS_ERR(vec))
+ goto userptr_fail_pfnvec;
+ buf->vec = vec;
+
+ buf->pages = frame_vector_pages(vec);
+ if (IS_ERR(buf->pages))
+ goto userptr_fail_sgtable;
+ buf->num_pages = frame_vector_count(vec);
if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
buf->num_pages, buf->offset, size, 0))
- goto userptr_fail_alloc_table_from_pages;
+ goto userptr_fail_sgtable;
sgt = &buf->sg_table;
/*
@@ -326,19 +274,9 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
userptr_fail_map:
sg_free_table(&buf->sg_table);
-userptr_fail_alloc_table_from_pages:
-userptr_fail_get_user_pages:
- dprintk(1, "get_user_pages requested/got: %d/%d]\n",
- buf->num_pages, num_pages_from_user);
- if (!vma_is_io(buf->vma))
- while (--num_pages_from_user >= 0)
- put_page(buf->pages[num_pages_from_user]);
- down_read(¤t->mm->mmap_sem);
- vb2_put_vma(buf->vma);
-userptr_fail_find_vma:
- up_read(¤t->mm->mmap_sem);
- kfree(buf->pages);
-userptr_fail_alloc_pages:
+userptr_fail_sgtable:
+ vb2_destroy_framevec(vec);
+userptr_fail_pfnvec:
kfree(buf);
return NULL;
}
@@ -366,13 +304,8 @@ static void vb2_dma_sg_put_userptr(void *buf_priv)
while (--i >= 0) {
if (buf->dma_dir == DMA_FROM_DEVICE)
set_page_dirty_lock(buf->pages[i]);
- if (!vma_is_io(buf->vma))
- put_page(buf->pages[i]);
}
- kfree(buf->pages);
- down_read(¤t->mm->mmap_sem);
- vb2_put_vma(buf->vma);
- up_read(¤t->mm->mmap_sem);
+ vb2_destroy_framevec(buf->vec);
kfree(buf);
}
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 5/9] [media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (3 preceding siblings ...)
2015-06-10 9:20 ` [PATCH 4/9] [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 6/9] [media] media: vb2: Convert vb2_dc_get_userptr() " Mauro Carvalho Chehab
` (6 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Pawel Osciak, Marek Szyprowski, Kyungmin Park, Hans Verkuil,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Convert vb2_vmalloc_get_userptr() to use frame vector infrastructure.
When we are doing that there's no need to allocate page array and some
code can be simplified.
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c
index f6656fefc035..ecb8f0c7f025 100644
--- a/drivers/media/v4l2-core/videobuf2-vmalloc.c
+++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c
@@ -23,11 +23,9 @@
struct vb2_vmalloc_buf {
void *vaddr;
- struct page **pages;
- struct vm_area_struct *vma;
+ struct frame_vector *vec;
enum dma_data_direction dma_dir;
unsigned long size;
- unsigned int n_pages;
atomic_t refcount;
struct vb2_vmarea_handler handler;
struct dma_buf *dbuf;
@@ -76,10 +74,8 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
enum dma_data_direction dma_dir)
{
struct vb2_vmalloc_buf *buf;
- unsigned long first, last;
- int n_pages, offset;
- struct vm_area_struct *vma;
- dma_addr_t physp;
+ struct frame_vector *vec;
+ int n_pages, offset, i;
buf = kzalloc(sizeof(*buf), GFP_KERNEL);
if (!buf)
@@ -88,53 +84,36 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
buf->dma_dir = dma_dir;
offset = vaddr & ~PAGE_MASK;
buf->size = size;
+ vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE);
+ if (IS_ERR(vec))
+ goto fail_pfnvec_create;
+ buf->vec = vec;
+ n_pages = frame_vector_count(vec);
+ if (frame_vector_to_pages(vec) < 0) {
+ unsigned long *nums = frame_vector_pfns(vec);
- down_read(¤t->mm->mmap_sem);
- vma = find_vma(current->mm, vaddr);
- if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) {
- if (vb2_get_contig_userptr(vaddr, size, &vma, &physp))
- goto fail_pages_array_alloc;
- buf->vma = vma;
- buf->vaddr = (__force void *)ioremap_nocache(physp, size);
- if (!buf->vaddr)
- goto fail_pages_array_alloc;
+ /*
+ * We cannot get page pointers for these pfns. Check memory is
+ * physically contiguous and use direct mapping.
+ */
+ for (i = 1; i < n_pages; i++)
+ if (nums[i-1] + 1 != nums[i])
+ goto fail_map;
+ buf->vaddr = (__force void *)
+ ioremap_nocache(nums[0] << PAGE_SHIFT, size);
} else {
- first = vaddr >> PAGE_SHIFT;
- last = (vaddr + size - 1) >> PAGE_SHIFT;
- buf->n_pages = last - first + 1;
- buf->pages = kzalloc(buf->n_pages * sizeof(struct page *),
- GFP_KERNEL);
- if (!buf->pages)
- goto fail_pages_array_alloc;
-
- /* current->mm->mmap_sem is taken by videobuf2 core */
- n_pages = get_user_pages(current, current->mm,
- vaddr & PAGE_MASK, buf->n_pages,
- dma_dir == DMA_FROM_DEVICE,
- 1, /* force */
- buf->pages, NULL);
- if (n_pages != buf->n_pages)
- goto fail_get_user_pages;
-
- buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1,
+ buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1,
PAGE_KERNEL);
- if (!buf->vaddr)
- goto fail_get_user_pages;
}
- up_read(¤t->mm->mmap_sem);
+ if (!buf->vaddr)
+ goto fail_map;
buf->vaddr += offset;
return buf;
-fail_get_user_pages:
- pr_debug("get_user_pages requested/got: %d/%d]\n", n_pages,
- buf->n_pages);
- while (--n_pages >= 0)
- put_page(buf->pages[n_pages]);
- kfree(buf->pages);
-
-fail_pages_array_alloc:
- up_read(¤t->mm->mmap_sem);
+fail_map:
+ vb2_destroy_framevec(vec);
+fail_pfnvec_create:
kfree(buf);
return NULL;
@@ -145,22 +124,21 @@ static void vb2_vmalloc_put_userptr(void *buf_priv)
struct vb2_vmalloc_buf *buf = buf_priv;
unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
unsigned int i;
+ struct page **pages;
+ unsigned int n_pages;
- down_read(¤t->mm->mmap_sem);
- if (buf->pages) {
+ if (!buf->vec->is_pfns) {
+ n_pages = frame_vector_count(buf->vec);
+ pages = frame_vector_pages(buf->vec);
if (vaddr)
- vm_unmap_ram((void *)vaddr, buf->n_pages);
- for (i = 0; i < buf->n_pages; ++i) {
- if (buf->dma_dir == DMA_FROM_DEVICE)
- set_page_dirty_lock(buf->pages[i]);
- put_page(buf->pages[i]);
- }
- kfree(buf->pages);
+ vm_unmap_ram((void *)vaddr, n_pages);
+ if (buf->dma_dir == DMA_FROM_DEVICE)
+ for (i = 0; i < n_pages; i++)
+ set_page_dirty_lock(pages[i]);
} else {
- vb2_put_vma(buf->vma);
iounmap((__force void __iomem *)buf->vaddr);
}
- up_read(¤t->mm->mmap_sem);
+ vb2_destroy_framevec(buf->vec);
kfree(buf);
}
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 6/9] [media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (4 preceding siblings ...)
2015-06-10 9:20 ` [PATCH 5/9] [media] media: vb2: Convert vb2_vmalloc_get_userptr() " Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 7/9] [media] media: vb2: Remove unused functions Mauro Carvalho Chehab
` (5 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Pawel Osciak, Marek Szyprowski, Kyungmin Park, Hans Verkuil,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Convert vb2_dc_get_userptr() to use frame vector infrastructure. When we
are doing that there's no need to allocate page array and some code can
be simplified.
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index 369df95af5c7..2397ceb1dc6b 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -32,15 +32,13 @@ struct vb2_dc_buf {
dma_addr_t dma_addr;
enum dma_data_direction dma_dir;
struct sg_table *dma_sgt;
+ struct frame_vector *vec;
/* MMAP related */
struct vb2_vmarea_handler handler;
atomic_t refcount;
struct sg_table *sgt_base;
- /* USERPTR related */
- struct vm_area_struct *vma;
-
/* DMABUF related */
struct dma_buf_attachment *db_attach;
};
@@ -49,24 +47,6 @@ struct vb2_dc_buf {
/* scatterlist table functions */
/*********************************************/
-
-static void vb2_dc_sgt_foreach_page(struct sg_table *sgt,
- void (*cb)(struct page *pg))
-{
- struct scatterlist *s;
- unsigned int i;
-
- for_each_sg(sgt->sgl, s, sgt->orig_nents, i) {
- struct page *page = sg_page(s);
- unsigned int n_pages = PAGE_ALIGN(s->offset + s->length)
- >> PAGE_SHIFT;
- unsigned int j;
-
- for (j = 0; j < n_pages; ++j, ++page)
- cb(page);
- }
-}
-
static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt)
{
struct scatterlist *s;
@@ -429,92 +409,12 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags)
/* callbacks for USERPTR buffers */
/*********************************************/
-static inline int vma_is_io(struct vm_area_struct *vma)
-{
- return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
-}
-
-static int vb2_dc_get_user_pfn(unsigned long start, int n_pages,
- struct vm_area_struct *vma, unsigned long *res)
-{
- unsigned long pfn, start_pfn, prev_pfn;
- unsigned int i;
- int ret;
-
- if (!vma_is_io(vma))
- return -EFAULT;
-
- ret = follow_pfn(vma, start, &pfn);
- if (ret)
- return ret;
-
- start_pfn = pfn;
- start += PAGE_SIZE;
-
- for (i = 1; i < n_pages; ++i, start += PAGE_SIZE) {
- prev_pfn = pfn;
- ret = follow_pfn(vma, start, &pfn);
-
- if (ret) {
- pr_err("no page for address %lu\n", start);
- return ret;
- }
- if (pfn != prev_pfn + 1)
- return -EINVAL;
- }
-
- *res = start_pfn;
- return 0;
-}
-
-static int vb2_dc_get_user_pages(unsigned long start, struct page **pages,
- int n_pages, struct vm_area_struct *vma,
- enum dma_data_direction dma_dir)
-{
- if (vma_is_io(vma)) {
- unsigned int i;
-
- for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) {
- unsigned long pfn;
- int ret = follow_pfn(vma, start, &pfn);
-
- if (!pfn_valid(pfn))
- return -EINVAL;
-
- if (ret) {
- pr_err("no page for address %lu\n", start);
- return ret;
- }
- pages[i] = pfn_to_page(pfn);
- }
- } else {
- int n;
-
- n = get_user_pages(current, current->mm, start & PAGE_MASK,
- n_pages, dma_dir == DMA_FROM_DEVICE, 1, pages, NULL);
- /* negative error means that no page was pinned */
- n = max(n, 0);
- if (n != n_pages) {
- pr_err("got only %d of %d user pages\n", n, n_pages);
- while (n)
- put_page(pages[--n]);
- return -EFAULT;
- }
- }
-
- return 0;
-}
-
-static void vb2_dc_put_dirty_page(struct page *page)
-{
- set_page_dirty_lock(page);
- put_page(page);
-}
-
static void vb2_dc_put_userptr(void *buf_priv)
{
struct vb2_dc_buf *buf = buf_priv;
struct sg_table *sgt = buf->dma_sgt;
+ int i;
+ struct page **pages;
if (sgt) {
DEFINE_DMA_ATTRS(attrs);
@@ -526,15 +426,15 @@ static void vb2_dc_put_userptr(void *buf_priv)
*/
dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir, &attrs);
- if (!vma_is_io(buf->vma))
- vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page);
-
+ pages = frame_vector_pages(buf->vec);
+ /* sgt should exist only if vector contains pages... */
+ BUG_ON(IS_ERR(pages));
+ for (i = 0; i < frame_vector_count(buf->vec); i++)
+ set_page_dirty_lock(pages[i]);
sg_free_table(sgt);
kfree(sgt);
}
- down_read(¤t->mm->mmap_sem);
- vb2_put_vma(buf->vma);
- up_read(¤t->mm->mmap_sem);
+ vb2_destroy_framevec(buf->vec);
kfree(buf);
}
@@ -574,13 +474,10 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
{
struct vb2_dc_conf *conf = alloc_ctx;
struct vb2_dc_buf *buf;
- unsigned long start;
- unsigned long end;
+ struct frame_vector *vec;
unsigned long offset;
- struct page **pages;
- int n_pages;
+ int n_pages, i;
int ret = 0;
- struct vm_area_struct *vma;
struct sg_table *sgt;
unsigned long contig_size;
unsigned long dma_align = dma_get_cache_alignment();
@@ -606,75 +503,43 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
buf->dev = conf->dev;
buf->dma_dir = dma_dir;
- start = vaddr & PAGE_MASK;
offset = vaddr & ~PAGE_MASK;
- end = PAGE_ALIGN(vaddr + size);
- n_pages = (end - start) >> PAGE_SHIFT;
-
- pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL);
- if (!pages) {
- ret = -ENOMEM;
- pr_err("failed to allocate pages table\n");
+ vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE);
+ if (IS_ERR(vec)) {
+ ret = PTR_ERR(vec);
goto fail_buf;
}
+ buf->vec = vec;
+ n_pages = frame_vector_count(vec);
+ ret = frame_vector_to_pages(vec);
+ if (ret < 0) {
+ unsigned long *nums = frame_vector_pfns(vec);
- down_read(¤t->mm->mmap_sem);
- /* current->mm->mmap_sem is taken by videobuf2 core */
- vma = find_vma(current->mm, vaddr);
- if (!vma) {
- pr_err("no vma for address %lu\n", vaddr);
- ret = -EFAULT;
- goto fail_pages;
+ /*
+ * Failed to convert to pages... Check the memory is physically
+ * contiguous and use direct mapping
+ */
+ for (i = 1; i < n_pages; i++)
+ if (nums[i-1] + 1 != nums[i])
+ goto fail_pfnvec;
+ buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, nums[0]);
+ goto out;
}
- if (vma->vm_end < vaddr + size) {
- pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size);
- ret = -EFAULT;
- goto fail_pages;
- }
-
- buf->vma = vb2_get_vma(vma);
- if (!buf->vma) {
- pr_err("failed to copy vma\n");
- ret = -ENOMEM;
- goto fail_pages;
- }
-
- /* extract page list from userspace mapping */
- ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, dma_dir);
- if (ret) {
- unsigned long pfn;
- if (vb2_dc_get_user_pfn(start, n_pages, vma, &pfn) == 0) {
- up_read(¤t->mm->mmap_sem);
- buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, pfn);
- buf->size = size;
- kfree(pages);
- return buf;
- }
-
- pr_err("failed to get user pages\n");
- goto fail_vma;
- }
- up_read(¤t->mm->mmap_sem);
-
sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
if (!sgt) {
pr_err("failed to allocate sg table\n");
ret = -ENOMEM;
- goto fail_get_user_pages;
+ goto fail_pfnvec;
}
- ret = sg_alloc_table_from_pages(sgt, pages, n_pages,
+ ret = sg_alloc_table_from_pages(sgt, frame_vector_pages(vec), n_pages,
offset, size, GFP_KERNEL);
if (ret) {
pr_err("failed to initialize sg table\n");
goto fail_sgt;
}
- /* pages are no longer needed */
- kfree(pages);
- pages = NULL;
-
/*
* No need to sync to the device, this will happen later when the
* prepare() memop is called.
@@ -696,8 +561,9 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
}
buf->dma_addr = sg_dma_address(sgt->sgl);
- buf->size = size;
buf->dma_sgt = sgt;
+out:
+ buf->size = size;
return buf;
@@ -706,25 +572,13 @@ fail_map_sg:
buf->dma_dir, &attrs);
fail_sgt_init:
- if (!vma_is_io(buf->vma))
- vb2_dc_sgt_foreach_page(sgt, put_page);
sg_free_table(sgt);
fail_sgt:
kfree(sgt);
-fail_get_user_pages:
- if (pages && !vma_is_io(buf->vma))
- while (n_pages)
- put_page(pages[--n_pages]);
-
- down_read(¤t->mm->mmap_sem);
-fail_vma:
- vb2_put_vma(buf->vma);
-
-fail_pages:
- up_read(¤t->mm->mmap_sem);
- kfree(pages); /* kfree is NULL-proof */
+fail_pfnvec:
+ vb2_destroy_framevec(vec);
fail_buf:
kfree(buf);
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 7/9] [media] media: vb2: Remove unused functions
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (5 preceding siblings ...)
2015-06-10 9:20 ` [PATCH 6/9] [media] media: vb2: Convert vb2_dc_get_userptr() " Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` Mauro Carvalho Chehab
` (4 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Pawel Osciak, Marek Szyprowski, Kyungmin Park, Hans Verkuil,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Conversion to the use of pinned pfns made some functions unused. Remove
them. Also there's no need to lock mmap_sem in __buf_prepare() anymore.
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/v4l2-core/videobuf2-memops.c b/drivers/media/v4l2-core/videobuf2-memops.c
index 0ec186d41b9b..48c6a49c4928 100644
--- a/drivers/media/v4l2-core/videobuf2-memops.c
+++ b/drivers/media/v4l2-core/videobuf2-memops.c
@@ -23,120 +23,6 @@
#include <media/videobuf2-memops.h>
/**
- * vb2_get_vma() - acquire and lock the virtual memory area
- * @vma: given virtual memory area
- *
- * This function attempts to acquire an area mapped in the userspace for
- * the duration of a hardware operation. The area is "locked" by performing
- * the same set of operation that are done when process calls fork() and
- * memory areas are duplicated.
- *
- * Returns a copy of a virtual memory region on success or NULL.
- */
-struct vm_area_struct *vb2_get_vma(struct vm_area_struct *vma)
-{
- struct vm_area_struct *vma_copy;
-
- vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL);
- if (vma_copy == NULL)
- return NULL;
-
- if (vma->vm_ops && vma->vm_ops->open)
- vma->vm_ops->open(vma);
-
- if (vma->vm_file)
- get_file(vma->vm_file);
-
- memcpy(vma_copy, vma, sizeof(*vma));
-
- vma_copy->vm_mm = NULL;
- vma_copy->vm_next = NULL;
- vma_copy->vm_prev = NULL;
-
- return vma_copy;
-}
-EXPORT_SYMBOL_GPL(vb2_get_vma);
-
-/**
- * vb2_put_userptr() - release a userspace virtual memory area
- * @vma: virtual memory region associated with the area to be released
- *
- * This function releases the previously acquired memory area after a hardware
- * operation.
- */
-void vb2_put_vma(struct vm_area_struct *vma)
-{
- if (!vma)
- return;
-
- if (vma->vm_ops && vma->vm_ops->close)
- vma->vm_ops->close(vma);
-
- if (vma->vm_file)
- fput(vma->vm_file);
-
- kfree(vma);
-}
-EXPORT_SYMBOL_GPL(vb2_put_vma);
-
-/**
- * vb2_get_contig_userptr() - lock physically contiguous userspace mapped memory
- * @vaddr: starting virtual address of the area to be verified
- * @size: size of the area
- * @res_paddr: will return physical address for the given vaddr
- * @res_vma: will return locked copy of struct vm_area for the given area
- *
- * This function will go through memory area of size @size mapped at @vaddr and
- * verify that the underlying physical pages are contiguous. If they are
- * contiguous the virtual memory area is locked and a @res_vma is filled with
- * the copy and @res_pa set to the physical address of the buffer.
- *
- * Returns 0 on success.
- */
-int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size,
- struct vm_area_struct **res_vma, dma_addr_t *res_pa)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- unsigned long offset, start, end;
- unsigned long this_pfn, prev_pfn;
- dma_addr_t pa = 0;
-
- start = vaddr;
- offset = start & ~PAGE_MASK;
- end = start + size;
-
- vma = find_vma(mm, start);
-
- if (vma == NULL || vma->vm_end < end)
- return -EFAULT;
-
- for (prev_pfn = 0; start < end; start += PAGE_SIZE) {
- int ret = follow_pfn(vma, start, &this_pfn);
- if (ret)
- return ret;
-
- if (prev_pfn == 0)
- pa = this_pfn << PAGE_SHIFT;
- else if (this_pfn != prev_pfn + 1)
- return -EFAULT;
-
- prev_pfn = this_pfn;
- }
-
- /*
- * Memory is contigous, lock vma and return to the caller
- */
- *res_vma = vb2_get_vma(vma);
- if (*res_vma == NULL)
- return -ENOMEM;
-
- *res_pa = pa + offset;
- return 0;
-}
-EXPORT_SYMBOL_GPL(vb2_get_contig_userptr);
-
-/**
* vb2_create_framevec() - map virtual addresses to pfns
* @start: Virtual user address where we start mapping
* @length: Length of a range to map
diff --git a/include/media/videobuf2-memops.h b/include/media/videobuf2-memops.h
index 2f0564ff5f31..830b5239fd8b 100644
--- a/include/media/videobuf2-memops.h
+++ b/include/media/videobuf2-memops.h
@@ -31,12 +31,6 @@ struct vb2_vmarea_handler {
extern const struct vm_operations_struct vb2_common_vm_ops;
-int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size,
- struct vm_area_struct **res_vma, dma_addr_t *res_pa);
-
-struct vm_area_struct *vb2_get_vma(struct vm_area_struct *vma);
-void vb2_put_vma(struct vm_area_struct *vma);
-
struct frame_vector *vb2_create_framevec(unsigned long start,
unsigned long length,
bool write);
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 8/9] [media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames()
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() Mauro Carvalho Chehab
` (10 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Inki Dae, Joonyoung Shim, Seung-Woo Kim, Kyungmin Park,
David Airlie, Kukjin Kim, dri-devel, linux-arm-kernel,
linux-samsung-soc, Hans Verkuil, Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
Convert g2d_userptr_get_dma_addr() to pin pages using get_vaddr_frames().
This removes the knowledge about vmas and mmap_sem locking from exynos
driver. Also it fixes a problem that the function has been mapping user
provided address without holding mmap_sem.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
index 81a250830808..810e1ee7c07d 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
@@ -190,10 +190,8 @@ struct g2d_cmdlist_userptr {
dma_addr_t dma_addr;
unsigned long userptr;
unsigned long size;
- struct page **pages;
- unsigned int npages;
+ struct frame_vector *vec;
struct sg_table *sgt;
- struct vm_area_struct *vma;
atomic_t refcount;
bool in_pool;
bool out_of_list;
@@ -363,6 +361,7 @@ static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev,
{
struct g2d_cmdlist_userptr *g2d_userptr =
(struct g2d_cmdlist_userptr *)obj;
+ struct page **pages;
if (!obj)
return;
@@ -382,19 +381,21 @@ out:
exynos_gem_unmap_sgt_from_dma(drm_dev, g2d_userptr->sgt,
DMA_BIDIRECTIONAL);
- exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
- g2d_userptr->npages,
- g2d_userptr->vma);
+ pages = frame_vector_pages(g2d_userptr->vec);
+ if (!IS_ERR(pages)) {
+ int i;
- exynos_gem_put_vma(g2d_userptr->vma);
+ for (i = 0; i < frame_vector_count(g2d_userptr->vec); i++)
+ set_page_dirty_lock(pages[i]);
+ }
+ put_vaddr_frames(g2d_userptr->vec);
+ frame_vector_destroy(g2d_userptr->vec);
if (!g2d_userptr->out_of_list)
list_del_init(&g2d_userptr->list);
sg_free_table(g2d_userptr->sgt);
kfree(g2d_userptr->sgt);
-
- drm_free_large(g2d_userptr->pages);
kfree(g2d_userptr);
}
@@ -408,9 +409,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
struct exynos_drm_g2d_private *g2d_priv = file_priv->g2d_priv;
struct g2d_cmdlist_userptr *g2d_userptr;
struct g2d_data *g2d;
- struct page **pages;
struct sg_table *sgt;
- struct vm_area_struct *vma;
unsigned long start, end;
unsigned int npages, offset;
int ret;
@@ -456,65 +455,38 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
return ERR_PTR(-ENOMEM);
atomic_set(&g2d_userptr->refcount, 1);
+ g2d_userptr->size = size;
start = userptr & PAGE_MASK;
offset = userptr & ~PAGE_MASK;
end = PAGE_ALIGN(userptr + size);
npages = (end - start) >> PAGE_SHIFT;
- g2d_userptr->npages = npages;
-
- pages = drm_calloc_large(npages, sizeof(struct page *));
- if (!pages) {
- DRM_ERROR("failed to allocate pages.\n");
- ret = -ENOMEM;
+ g2d_userptr->vec = frame_vector_create(npages);
+ if (!vec)
goto err_free;
- }
- down_read(¤t->mm->mmap_sem);
- vma = find_vma(current->mm, userptr);
- if (!vma) {
- up_read(¤t->mm->mmap_sem);
- DRM_ERROR("failed to get vm region.\n");
- ret = -EFAULT;
- goto err_free_pages;
- }
-
- if (vma->vm_end < userptr + size) {
- up_read(¤t->mm->mmap_sem);
- DRM_ERROR("vma is too small.\n");
- ret = -EFAULT;
- goto err_free_pages;
- }
-
- g2d_userptr->vma = exynos_gem_get_vma(vma);
- if (!g2d_userptr->vma) {
- up_read(¤t->mm->mmap_sem);
- DRM_ERROR("failed to copy vma.\n");
- ret = -ENOMEM;
- goto err_free_pages;
- }
-
- g2d_userptr->size = size;
-
- ret = exynos_gem_get_pages_from_userptr(start & PAGE_MASK,
- npages, pages, vma);
- if (ret < 0) {
- up_read(¤t->mm->mmap_sem);
+ ret = get_vaddr_frames(start, npages, true, true, g2d_userptr->vec);
+ if (ret != npages) {
DRM_ERROR("failed to get user pages from userptr.\n");
- goto err_put_vma;
+ if (ret < 0)
+ goto err_destroy_framevec;
+ ret = -EFAULT;
+ goto err_put_framevec;
+ }
+ if (frame_vector_to_pages(g2d_userptr->vec) < 0) {
+ ret = -EFAULT;
+ goto err_put_framevec;
}
-
- up_read(¤t->mm->mmap_sem);
- g2d_userptr->pages = pages;
sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
if (!sgt) {
ret = -ENOMEM;
- goto err_free_userptr;
+ goto err_put_framevec;
}
- ret = sg_alloc_table_from_pages(sgt, pages, npages, offset,
- size, GFP_KERNEL);
+ ret = sg_alloc_table_from_pages(sgt,
+ frame_vector_pages(g2d_userptr->vec),
+ npages, offset, size, GFP_KERNEL);
if (ret < 0) {
DRM_ERROR("failed to get sgt from pages.\n");
goto err_free_sgt;
@@ -549,16 +521,11 @@ err_sg_free_table:
err_free_sgt:
kfree(sgt);
-err_free_userptr:
- exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
- g2d_userptr->npages,
- g2d_userptr->vma);
+err_put_framevec:
+ put_vaddr_frames(g2d_userptr->vec);
-err_put_vma:
- exynos_gem_put_vma(g2d_userptr->vma);
-
-err_free_pages:
- drm_free_large(pages);
+err_destroy_framevec:
+ frame_vector_destroy(g2d_userptr->vec);
err_free:
kfree(g2d_userptr);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 0d5b9698d384..47068ae44ced 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -378,103 +378,6 @@ int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
return 0;
}
-struct vm_area_struct *exynos_gem_get_vma(struct vm_area_struct *vma)
-{
- struct vm_area_struct *vma_copy;
-
- vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL);
- if (!vma_copy)
- return NULL;
-
- if (vma->vm_ops && vma->vm_ops->open)
- vma->vm_ops->open(vma);
-
- if (vma->vm_file)
- get_file(vma->vm_file);
-
- memcpy(vma_copy, vma, sizeof(*vma));
-
- vma_copy->vm_mm = NULL;
- vma_copy->vm_next = NULL;
- vma_copy->vm_prev = NULL;
-
- return vma_copy;
-}
-
-void exynos_gem_put_vma(struct vm_area_struct *vma)
-{
- if (!vma)
- return;
-
- if (vma->vm_ops && vma->vm_ops->close)
- vma->vm_ops->close(vma);
-
- if (vma->vm_file)
- fput(vma->vm_file);
-
- kfree(vma);
-}
-
-int exynos_gem_get_pages_from_userptr(unsigned long start,
- unsigned int npages,
- struct page **pages,
- struct vm_area_struct *vma)
-{
- int get_npages;
-
- /* the memory region mmaped with VM_PFNMAP. */
- if (vma_is_io(vma)) {
- unsigned int i;
-
- for (i = 0; i < npages; ++i, start += PAGE_SIZE) {
- unsigned long pfn;
- int ret = follow_pfn(vma, start, &pfn);
- if (ret)
- return ret;
-
- pages[i] = pfn_to_page(pfn);
- }
-
- if (i != npages) {
- DRM_ERROR("failed to get user_pages.\n");
- return -EINVAL;
- }
-
- return 0;
- }
-
- get_npages = get_user_pages(current, current->mm, start,
- npages, 1, 1, pages, NULL);
- get_npages = max(get_npages, 0);
- if (get_npages != npages) {
- DRM_ERROR("failed to get user_pages.\n");
- while (get_npages)
- put_page(pages[--get_npages]);
- return -EFAULT;
- }
-
- return 0;
-}
-
-void exynos_gem_put_pages_to_userptr(struct page **pages,
- unsigned int npages,
- struct vm_area_struct *vma)
-{
- if (!vma_is_io(vma)) {
- unsigned int i;
-
- for (i = 0; i < npages; i++) {
- set_page_dirty_lock(pages[i]);
-
- /*
- * undo the reference we took when populating
- * the table.
- */
- put_page(pages[i]);
- }
- }
-}
-
int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev,
struct sg_table *sgt,
enum dma_data_direction dir)
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 8/9] [media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames()
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
0 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: linux-arm-kernel
From: Jan Kara <jack@suse.cz>
Convert g2d_userptr_get_dma_addr() to pin pages using get_vaddr_frames().
This removes the knowledge about vmas and mmap_sem locking from exynos
driver. Also it fixes a problem that the function has been mapping user
provided address without holding mmap_sem.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
index 81a250830808..810e1ee7c07d 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
@@ -190,10 +190,8 @@ struct g2d_cmdlist_userptr {
dma_addr_t dma_addr;
unsigned long userptr;
unsigned long size;
- struct page **pages;
- unsigned int npages;
+ struct frame_vector *vec;
struct sg_table *sgt;
- struct vm_area_struct *vma;
atomic_t refcount;
bool in_pool;
bool out_of_list;
@@ -363,6 +361,7 @@ static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev,
{
struct g2d_cmdlist_userptr *g2d_userptr =
(struct g2d_cmdlist_userptr *)obj;
+ struct page **pages;
if (!obj)
return;
@@ -382,19 +381,21 @@ out:
exynos_gem_unmap_sgt_from_dma(drm_dev, g2d_userptr->sgt,
DMA_BIDIRECTIONAL);
- exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
- g2d_userptr->npages,
- g2d_userptr->vma);
+ pages = frame_vector_pages(g2d_userptr->vec);
+ if (!IS_ERR(pages)) {
+ int i;
- exynos_gem_put_vma(g2d_userptr->vma);
+ for (i = 0; i < frame_vector_count(g2d_userptr->vec); i++)
+ set_page_dirty_lock(pages[i]);
+ }
+ put_vaddr_frames(g2d_userptr->vec);
+ frame_vector_destroy(g2d_userptr->vec);
if (!g2d_userptr->out_of_list)
list_del_init(&g2d_userptr->list);
sg_free_table(g2d_userptr->sgt);
kfree(g2d_userptr->sgt);
-
- drm_free_large(g2d_userptr->pages);
kfree(g2d_userptr);
}
@@ -408,9 +409,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
struct exynos_drm_g2d_private *g2d_priv = file_priv->g2d_priv;
struct g2d_cmdlist_userptr *g2d_userptr;
struct g2d_data *g2d;
- struct page **pages;
struct sg_table *sgt;
- struct vm_area_struct *vma;
unsigned long start, end;
unsigned int npages, offset;
int ret;
@@ -456,65 +455,38 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
return ERR_PTR(-ENOMEM);
atomic_set(&g2d_userptr->refcount, 1);
+ g2d_userptr->size = size;
start = userptr & PAGE_MASK;
offset = userptr & ~PAGE_MASK;
end = PAGE_ALIGN(userptr + size);
npages = (end - start) >> PAGE_SHIFT;
- g2d_userptr->npages = npages;
-
- pages = drm_calloc_large(npages, sizeof(struct page *));
- if (!pages) {
- DRM_ERROR("failed to allocate pages.\n");
- ret = -ENOMEM;
+ g2d_userptr->vec = frame_vector_create(npages);
+ if (!vec)
goto err_free;
- }
- down_read(¤t->mm->mmap_sem);
- vma = find_vma(current->mm, userptr);
- if (!vma) {
- up_read(¤t->mm->mmap_sem);
- DRM_ERROR("failed to get vm region.\n");
- ret = -EFAULT;
- goto err_free_pages;
- }
-
- if (vma->vm_end < userptr + size) {
- up_read(¤t->mm->mmap_sem);
- DRM_ERROR("vma is too small.\n");
- ret = -EFAULT;
- goto err_free_pages;
- }
-
- g2d_userptr->vma = exynos_gem_get_vma(vma);
- if (!g2d_userptr->vma) {
- up_read(¤t->mm->mmap_sem);
- DRM_ERROR("failed to copy vma.\n");
- ret = -ENOMEM;
- goto err_free_pages;
- }
-
- g2d_userptr->size = size;
-
- ret = exynos_gem_get_pages_from_userptr(start & PAGE_MASK,
- npages, pages, vma);
- if (ret < 0) {
- up_read(¤t->mm->mmap_sem);
+ ret = get_vaddr_frames(start, npages, true, true, g2d_userptr->vec);
+ if (ret != npages) {
DRM_ERROR("failed to get user pages from userptr.\n");
- goto err_put_vma;
+ if (ret < 0)
+ goto err_destroy_framevec;
+ ret = -EFAULT;
+ goto err_put_framevec;
+ }
+ if (frame_vector_to_pages(g2d_userptr->vec) < 0) {
+ ret = -EFAULT;
+ goto err_put_framevec;
}
-
- up_read(¤t->mm->mmap_sem);
- g2d_userptr->pages = pages;
sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
if (!sgt) {
ret = -ENOMEM;
- goto err_free_userptr;
+ goto err_put_framevec;
}
- ret = sg_alloc_table_from_pages(sgt, pages, npages, offset,
- size, GFP_KERNEL);
+ ret = sg_alloc_table_from_pages(sgt,
+ frame_vector_pages(g2d_userptr->vec),
+ npages, offset, size, GFP_KERNEL);
if (ret < 0) {
DRM_ERROR("failed to get sgt from pages.\n");
goto err_free_sgt;
@@ -549,16 +521,11 @@ err_sg_free_table:
err_free_sgt:
kfree(sgt);
-err_free_userptr:
- exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
- g2d_userptr->npages,
- g2d_userptr->vma);
+err_put_framevec:
+ put_vaddr_frames(g2d_userptr->vec);
-err_put_vma:
- exynos_gem_put_vma(g2d_userptr->vma);
-
-err_free_pages:
- drm_free_large(pages);
+err_destroy_framevec:
+ frame_vector_destroy(g2d_userptr->vec);
err_free:
kfree(g2d_userptr);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 0d5b9698d384..47068ae44ced 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -378,103 +378,6 @@ int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
return 0;
}
-struct vm_area_struct *exynos_gem_get_vma(struct vm_area_struct *vma)
-{
- struct vm_area_struct *vma_copy;
-
- vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL);
- if (!vma_copy)
- return NULL;
-
- if (vma->vm_ops && vma->vm_ops->open)
- vma->vm_ops->open(vma);
-
- if (vma->vm_file)
- get_file(vma->vm_file);
-
- memcpy(vma_copy, vma, sizeof(*vma));
-
- vma_copy->vm_mm = NULL;
- vma_copy->vm_next = NULL;
- vma_copy->vm_prev = NULL;
-
- return vma_copy;
-}
-
-void exynos_gem_put_vma(struct vm_area_struct *vma)
-{
- if (!vma)
- return;
-
- if (vma->vm_ops && vma->vm_ops->close)
- vma->vm_ops->close(vma);
-
- if (vma->vm_file)
- fput(vma->vm_file);
-
- kfree(vma);
-}
-
-int exynos_gem_get_pages_from_userptr(unsigned long start,
- unsigned int npages,
- struct page **pages,
- struct vm_area_struct *vma)
-{
- int get_npages;
-
- /* the memory region mmaped with VM_PFNMAP. */
- if (vma_is_io(vma)) {
- unsigned int i;
-
- for (i = 0; i < npages; ++i, start += PAGE_SIZE) {
- unsigned long pfn;
- int ret = follow_pfn(vma, start, &pfn);
- if (ret)
- return ret;
-
- pages[i] = pfn_to_page(pfn);
- }
-
- if (i != npages) {
- DRM_ERROR("failed to get user_pages.\n");
- return -EINVAL;
- }
-
- return 0;
- }
-
- get_npages = get_user_pages(current, current->mm, start,
- npages, 1, 1, pages, NULL);
- get_npages = max(get_npages, 0);
- if (get_npages != npages) {
- DRM_ERROR("failed to get user_pages.\n");
- while (get_npages)
- put_page(pages[--get_npages]);
- return -EFAULT;
- }
-
- return 0;
-}
-
-void exynos_gem_put_pages_to_userptr(struct page **pages,
- unsigned int npages,
- struct vm_area_struct *vma)
-{
- if (!vma_is_io(vma)) {
- unsigned int i;
-
- for (i = 0; i < npages; i++) {
- set_page_dirty_lock(pages[i]);
-
- /*
- * undo the reference we took when populating
- * the table.
- */
- put_page(pages[i]);
- }
- }
-}
-
int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev,
struct sg_table *sgt,
enum dma_data_direction dir)
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread
* [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 2/9] [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() Mauro Carvalho Chehab
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
2015-06-10 9:20 ` [PATCH 4/9] [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector Mauro Carvalho Chehab
` (8 subsequent siblings)
11 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Inki Dae, Joonyoung Shim, Seung-Woo Kim, Kyungmin Park,
David Airlie, Kukjin Kim, Hans Verkuil, Paul Bolle, Randy Dunlap,
Jiri Kosina, Geert Uytterhoeven, Mark Brown, Dan Streetman,
Joonsoo Kim, Minchan Kim, Paul E. McKenney, Steve Capper,
Sasha Levin, Ganesh Mahendran, Christoph Jaeger, Michal Hocko,
Josh Triplett, Johannes Weiner, Andrey Ryabinin,
Konstantin Khlebnikov, Matthew Wilcox, Al Viro,
Kirill A. Shutemov, Christian Borntraeger, Andrea Arcangeli,
Paul Cassella, Aneesh Kumar K.V, Naoya Horiguchi, dri-devel,
linux-arm-kernel, linux-samsung-soc, linux-mm,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
get_vaddr_frames() is used by relatively rare drivers so hide it and the
related functions behind a config option that is selected only by
drivers that need the infrastructure.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
create mode 100644 mm/frame_vector.c
diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
index 0a6780367d28..fc678289cf79 100644
--- a/drivers/gpu/drm/exynos/Kconfig
+++ b/drivers/gpu/drm/exynos/Kconfig
@@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
config DRM_EXYNOS_G2D
bool "Exynos DRM G2D"
depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
+ select FRAME_VECTOR
help
Choose this option if you want to use Exynos G2D for DRM.
diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
index dc2aaab54aef..217d613b0fe7 100644
--- a/drivers/media/platform/omap/Kconfig
+++ b/drivers/media/platform/omap/Kconfig
@@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
+ select FRAME_VECTOR
default n
---help---
V4L2 Display driver support for OMAP2/3 based boards.
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index f7a01a72eb9e..f38f6e387f04 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
config VIDEOBUF2_MEMOPS
tristate
+ select FRAME_VECTOR
config VIDEOBUF2_DMA_CONTIG
tristate
diff --git a/mm/Kconfig b/mm/Kconfig
index 390214da4546..2ca52e9986f0 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
changed to a smaller value in which case that is used.
A sane initial value is 80 MB.
+
+config FRAME_VECTOR
+ bool
diff --git a/mm/Makefile b/mm/Makefile
index 98c4eaeabdcb..be5d5c866305 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
+obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
new file mode 100644
index 000000000000..31a2bd5f41d5
--- /dev/null
+++ b/mm/frame_vector.c
@@ -0,0 +1,232 @@
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+
+/*
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @write: whether pages will be written to by the caller
+ * @force: whether to force write access even if user mapping is
+ * readonly. See description of the same argument of
+ get_user_pages().
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_sem as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ bool write, bool force, struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+ int locked;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ down_read(&mm->mmap_sem);
+ locked = 1;
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ ret = get_user_pages_locked(current, mm, start, nr_frames,
+ write, force, (struct page **)(vec->ptrs), &locked);
+ goto out;
+ }
+
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /*
+ * We stop if we have enough pages or if VMA doesn't completely
+ * cover the tail page.
+ */
+ if (ret >= nr_frames || start < vma->vm_end)
+ break;
+ vma = find_vma_intersection(mm, start, start + 1);
+ } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+out:
+ if (locked)
+ up_read(&mm->mmap_sem);
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ int i;
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+ for (i = 0; i < vec->nr_frames; i++)
+ put_page(pages[i]);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ if (size <= PAGE_SIZE)
+ vec = kmalloc(size, GFP_KERNEL);
+ else
+ vec = vmalloc(size);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ if (!is_vmalloc_addr(vec))
+ kfree(vec);
+ else
+ vfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
diff --git a/mm/gup.c b/mm/gup.c
index 9d7f4fde30cb..222d57e335f9 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
return ret; /* 0 or negative error code */
}
-/*
- * get_vaddr_frames() - map virtual addresses to pfns
- * @start: starting user address
- * @nr_frames: number of pages / pfns from start to map
- * @write: whether pages will be written to by the caller
- * @force: whether to force write access even if user mapping is
- * readonly. See description of the same argument of
- get_user_pages().
- * @vec: structure which receives pages / pfns of the addresses mapped.
- * It should have space for at least nr_frames entries.
- *
- * This function maps virtual addresses from @start and fills @vec structure
- * with page frame numbers or page pointers to corresponding pages (choice
- * depends on the type of the vma underlying the virtual address). If @start
- * belongs to a normal vma, the function grabs reference to each of the pages
- * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
- * touch page structures and the caller must make sure pfns aren't reused for
- * anything else while he is using them.
- *
- * The function returns number of pages mapped which may be less than
- * @nr_frames. In particular we stop mapping if there are more vmas of
- * different type underlying the specified range of virtual addresses.
- * When the function isn't able to map a single page, it returns error.
- *
- * This function takes care of grabbing mmap_sem as necessary.
- */
-int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
- bool write, bool force, struct frame_vector *vec)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int ret = 0;
- int err;
- int locked;
-
- if (nr_frames == 0)
- return 0;
-
- if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
- nr_frames = vec->nr_allocated;
-
- down_read(&mm->mmap_sem);
- locked = 1;
- vma = find_vma_intersection(mm, start, start + 1);
- if (!vma) {
- ret = -EFAULT;
- goto out;
- }
- if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
- vec->got_ref = true;
- vec->is_pfns = false;
- ret = get_user_pages_locked(current, mm, start, nr_frames,
- write, force, (struct page **)(vec->ptrs), &locked);
- goto out;
- }
-
- vec->got_ref = false;
- vec->is_pfns = true;
- do {
- unsigned long *nums = frame_vector_pfns(vec);
-
- while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
- err = follow_pfn(vma, start, &nums[ret]);
- if (err) {
- if (ret == 0)
- ret = err;
- goto out;
- }
- start += PAGE_SIZE;
- ret++;
- }
- /*
- * We stop if we have enough pages or if VMA doesn't completely
- * cover the tail page.
- */
- if (ret >= nr_frames || start < vma->vm_end)
- break;
- vma = find_vma_intersection(mm, start, start + 1);
- } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
-out:
- if (locked)
- up_read(&mm->mmap_sem);
- if (!ret)
- ret = -EFAULT;
- if (ret > 0)
- vec->nr_frames = ret;
- return ret;
-}
-EXPORT_SYMBOL(get_vaddr_frames);
-
-/**
- * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
- * them
- * @vec: frame vector to put
- *
- * Drop references to pages if get_vaddr_frames() acquired them. We also
- * invalidate the frame vector so that it is prepared for the next call into
- * get_vaddr_frames().
- */
-void put_vaddr_frames(struct frame_vector *vec)
-{
- int i;
- struct page **pages;
-
- if (!vec->got_ref)
- goto out;
- pages = frame_vector_pages(vec);
- /*
- * frame_vector_pages() might needed to do a conversion when
- * get_vaddr_frames() got pages but vec was later converted to pfns.
- * But it shouldn't really fail to convert pfns back...
- */
- if (WARN_ON(IS_ERR(pages)))
- goto out;
- for (i = 0; i < vec->nr_frames; i++)
- put_page(pages[i]);
- vec->got_ref = false;
-out:
- vec->nr_frames = 0;
-}
-EXPORT_SYMBOL(put_vaddr_frames);
-
-/**
- * frame_vector_to_pages - convert frame vector to contain page pointers
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of page pointers. If the conversion is
- * successful, return 0. Otherwise return an error. Note that we do not grab
- * page references for the page structures.
- */
-int frame_vector_to_pages(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (!vec->is_pfns)
- return 0;
- nums = frame_vector_pfns(vec);
- for (i = 0; i < vec->nr_frames; i++)
- if (!pfn_valid(nums[i]))
- return -EINVAL;
- pages = (struct page **)nums;
- for (i = 0; i < vec->nr_frames; i++)
- pages[i] = pfn_to_page(nums[i]);
- vec->is_pfns = false;
- return 0;
-}
-EXPORT_SYMBOL(frame_vector_to_pages);
-
-/**
- * frame_vector_to_pfns - convert frame vector to contain pfns
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of pfns.
- */
-void frame_vector_to_pfns(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (vec->is_pfns)
- return;
- pages = (struct page **)(vec->ptrs);
- nums = (unsigned long *)pages;
- for (i = 0; i < vec->nr_frames; i++)
- nums[i] = page_to_pfn(pages[i]);
- vec->is_pfns = true;
-}
-EXPORT_SYMBOL(frame_vector_to_pfns);
-
-/**
- * frame_vector_create() - allocate & initialize structure for pinned pfns
- * @nr_frames: number of pfns slots we should reserve
- *
- * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
- * pfns.
- */
-struct frame_vector *frame_vector_create(unsigned int nr_frames)
-{
- struct frame_vector *vec;
- int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
-
- if (WARN_ON_ONCE(nr_frames == 0))
- return NULL;
- /*
- * This is absurdly high. It's here just to avoid strange effects when
- * arithmetics overflows.
- */
- if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
- return NULL;
- /*
- * Avoid higher order allocations, use vmalloc instead. It should
- * be rare anyway.
- */
- if (size <= PAGE_SIZE)
- vec = kmalloc(size, GFP_KERNEL);
- else
- vec = vmalloc(size);
- if (!vec)
- return NULL;
- vec->nr_allocated = nr_frames;
- vec->nr_frames = 0;
- return vec;
-}
-EXPORT_SYMBOL(frame_vector_create);
-
-/**
- * frame_vector_destroy() - free memory allocated to carry frame vector
- * @vec: Frame vector to free
- *
- * Free structure allocated by frame_vector_create() to carry frames.
- */
-void frame_vector_destroy(struct frame_vector *vec)
-{
- /* Make sure put_vaddr_frames() got called properly... */
- VM_BUG_ON(vec->nr_frames > 0);
- if (!is_vmalloc_addr(vec))
- kfree(vec);
- else
- vfree(vec);
-}
-EXPORT_SYMBOL(frame_vector_destroy);
-
/**
* get_dump_page() - pin user page in memory while writing it to core dump
* @addr: user address
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
0 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: linux-arm-kernel
From: Jan Kara <jack@suse.cz>
get_vaddr_frames() is used by relatively rare drivers so hide it and the
related functions behind a config option that is selected only by
drivers that need the infrastructure.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
create mode 100644 mm/frame_vector.c
diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
index 0a6780367d28..fc678289cf79 100644
--- a/drivers/gpu/drm/exynos/Kconfig
+++ b/drivers/gpu/drm/exynos/Kconfig
@@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
config DRM_EXYNOS_G2D
bool "Exynos DRM G2D"
depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
+ select FRAME_VECTOR
help
Choose this option if you want to use Exynos G2D for DRM.
diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
index dc2aaab54aef..217d613b0fe7 100644
--- a/drivers/media/platform/omap/Kconfig
+++ b/drivers/media/platform/omap/Kconfig
@@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
+ select FRAME_VECTOR
default n
---help---
V4L2 Display driver support for OMAP2/3 based boards.
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index f7a01a72eb9e..f38f6e387f04 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
config VIDEOBUF2_MEMOPS
tristate
+ select FRAME_VECTOR
config VIDEOBUF2_DMA_CONTIG
tristate
diff --git a/mm/Kconfig b/mm/Kconfig
index 390214da4546..2ca52e9986f0 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
changed to a smaller value in which case that is used.
A sane initial value is 80 MB.
+
+config FRAME_VECTOR
+ bool
diff --git a/mm/Makefile b/mm/Makefile
index 98c4eaeabdcb..be5d5c866305 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
+obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
new file mode 100644
index 000000000000..31a2bd5f41d5
--- /dev/null
+++ b/mm/frame_vector.c
@@ -0,0 +1,232 @@
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+
+/*
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @write: whether pages will be written to by the caller
+ * @force: whether to force write access even if user mapping is
+ * readonly. See description of the same argument of
+ get_user_pages().
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_sem as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ bool write, bool force, struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+ int locked;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ down_read(&mm->mmap_sem);
+ locked = 1;
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ ret = get_user_pages_locked(current, mm, start, nr_frames,
+ write, force, (struct page **)(vec->ptrs), &locked);
+ goto out;
+ }
+
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /*
+ * We stop if we have enough pages or if VMA doesn't completely
+ * cover the tail page.
+ */
+ if (ret >= nr_frames || start < vma->vm_end)
+ break;
+ vma = find_vma_intersection(mm, start, start + 1);
+ } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+out:
+ if (locked)
+ up_read(&mm->mmap_sem);
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ int i;
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+ for (i = 0; i < vec->nr_frames; i++)
+ put_page(pages[i]);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ if (size <= PAGE_SIZE)
+ vec = kmalloc(size, GFP_KERNEL);
+ else
+ vec = vmalloc(size);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ if (!is_vmalloc_addr(vec))
+ kfree(vec);
+ else
+ vfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
diff --git a/mm/gup.c b/mm/gup.c
index 9d7f4fde30cb..222d57e335f9 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
return ret; /* 0 or negative error code */
}
-/*
- * get_vaddr_frames() - map virtual addresses to pfns
- * @start: starting user address
- * @nr_frames: number of pages / pfns from start to map
- * @write: whether pages will be written to by the caller
- * @force: whether to force write access even if user mapping is
- * readonly. See description of the same argument of
- get_user_pages().
- * @vec: structure which receives pages / pfns of the addresses mapped.
- * It should have space for at least nr_frames entries.
- *
- * This function maps virtual addresses from @start and fills @vec structure
- * with page frame numbers or page pointers to corresponding pages (choice
- * depends on the type of the vma underlying the virtual address). If @start
- * belongs to a normal vma, the function grabs reference to each of the pages
- * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
- * touch page structures and the caller must make sure pfns aren't reused for
- * anything else while he is using them.
- *
- * The function returns number of pages mapped which may be less than
- * @nr_frames. In particular we stop mapping if there are more vmas of
- * different type underlying the specified range of virtual addresses.
- * When the function isn't able to map a single page, it returns error.
- *
- * This function takes care of grabbing mmap_sem as necessary.
- */
-int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
- bool write, bool force, struct frame_vector *vec)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int ret = 0;
- int err;
- int locked;
-
- if (nr_frames == 0)
- return 0;
-
- if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
- nr_frames = vec->nr_allocated;
-
- down_read(&mm->mmap_sem);
- locked = 1;
- vma = find_vma_intersection(mm, start, start + 1);
- if (!vma) {
- ret = -EFAULT;
- goto out;
- }
- if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
- vec->got_ref = true;
- vec->is_pfns = false;
- ret = get_user_pages_locked(current, mm, start, nr_frames,
- write, force, (struct page **)(vec->ptrs), &locked);
- goto out;
- }
-
- vec->got_ref = false;
- vec->is_pfns = true;
- do {
- unsigned long *nums = frame_vector_pfns(vec);
-
- while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
- err = follow_pfn(vma, start, &nums[ret]);
- if (err) {
- if (ret == 0)
- ret = err;
- goto out;
- }
- start += PAGE_SIZE;
- ret++;
- }
- /*
- * We stop if we have enough pages or if VMA doesn't completely
- * cover the tail page.
- */
- if (ret >= nr_frames || start < vma->vm_end)
- break;
- vma = find_vma_intersection(mm, start, start + 1);
- } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
-out:
- if (locked)
- up_read(&mm->mmap_sem);
- if (!ret)
- ret = -EFAULT;
- if (ret > 0)
- vec->nr_frames = ret;
- return ret;
-}
-EXPORT_SYMBOL(get_vaddr_frames);
-
-/**
- * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
- * them
- * @vec: frame vector to put
- *
- * Drop references to pages if get_vaddr_frames() acquired them. We also
- * invalidate the frame vector so that it is prepared for the next call into
- * get_vaddr_frames().
- */
-void put_vaddr_frames(struct frame_vector *vec)
-{
- int i;
- struct page **pages;
-
- if (!vec->got_ref)
- goto out;
- pages = frame_vector_pages(vec);
- /*
- * frame_vector_pages() might needed to do a conversion when
- * get_vaddr_frames() got pages but vec was later converted to pfns.
- * But it shouldn't really fail to convert pfns back...
- */
- if (WARN_ON(IS_ERR(pages)))
- goto out;
- for (i = 0; i < vec->nr_frames; i++)
- put_page(pages[i]);
- vec->got_ref = false;
-out:
- vec->nr_frames = 0;
-}
-EXPORT_SYMBOL(put_vaddr_frames);
-
-/**
- * frame_vector_to_pages - convert frame vector to contain page pointers
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of page pointers. If the conversion is
- * successful, return 0. Otherwise return an error. Note that we do not grab
- * page references for the page structures.
- */
-int frame_vector_to_pages(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (!vec->is_pfns)
- return 0;
- nums = frame_vector_pfns(vec);
- for (i = 0; i < vec->nr_frames; i++)
- if (!pfn_valid(nums[i]))
- return -EINVAL;
- pages = (struct page **)nums;
- for (i = 0; i < vec->nr_frames; i++)
- pages[i] = pfn_to_page(nums[i]);
- vec->is_pfns = false;
- return 0;
-}
-EXPORT_SYMBOL(frame_vector_to_pages);
-
-/**
- * frame_vector_to_pfns - convert frame vector to contain pfns
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of pfns.
- */
-void frame_vector_to_pfns(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (vec->is_pfns)
- return;
- pages = (struct page **)(vec->ptrs);
- nums = (unsigned long *)pages;
- for (i = 0; i < vec->nr_frames; i++)
- nums[i] = page_to_pfn(pages[i]);
- vec->is_pfns = true;
-}
-EXPORT_SYMBOL(frame_vector_to_pfns);
-
-/**
- * frame_vector_create() - allocate & initialize structure for pinned pfns
- * @nr_frames: number of pfns slots we should reserve
- *
- * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
- * pfns.
- */
-struct frame_vector *frame_vector_create(unsigned int nr_frames)
-{
- struct frame_vector *vec;
- int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
-
- if (WARN_ON_ONCE(nr_frames == 0))
- return NULL;
- /*
- * This is absurdly high. It's here just to avoid strange effects when
- * arithmetics overflows.
- */
- if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
- return NULL;
- /*
- * Avoid higher order allocations, use vmalloc instead. It should
- * be rare anyway.
- */
- if (size <= PAGE_SIZE)
- vec = kmalloc(size, GFP_KERNEL);
- else
- vec = vmalloc(size);
- if (!vec)
- return NULL;
- vec->nr_allocated = nr_frames;
- vec->nr_frames = 0;
- return vec;
-}
-EXPORT_SYMBOL(frame_vector_create);
-
-/**
- * frame_vector_destroy() - free memory allocated to carry frame vector
- * @vec: Frame vector to free
- *
- * Free structure allocated by frame_vector_create() to carry frames.
- */
-void frame_vector_destroy(struct frame_vector *vec)
-{
- /* Make sure put_vaddr_frames() got called properly... */
- VM_BUG_ON(vec->nr_frames > 0);
- if (!is_vmalloc_addr(vec))
- kfree(vec);
- else
- vfree(vec);
-}
-EXPORT_SYMBOL(frame_vector_destroy);
-
/**
* get_dump_page() - pin user page in memory while writing it to core dump
* @addr: user address
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
0 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Inki Dae, Joonyoung Shim, Seung-Woo Kim, Kyungmin Park,
David Airlie, Kukjin Kim, Hans Verkuil, Paul Bolle, Randy Dunlap,
Jiri Kosina, Geert Uytterhoeven, Mark Brown, Dan Streetman,
Joonsoo Kim, Minchan Kim, Paul E. McKenney, Steve Capper,
Sasha Levin, Ganesh Mahendran, Christoph Jaeger, Michal Hocko,
Josh Triplett, Johannes Weiner, Andrey Ryabinin,
Konstantin Khlebnikov, Matthew Wilcox, Al Viro,
Kirill A. Shutemov, Christian Borntraeger, Andrea Arcangeli,
Paul Cassella, Aneesh Kumar K.V, Naoya Horiguchi, dri-devel,
linux-arm-kernel, linux-samsung-soc, linux-mm,
Mauro Carvalho Chehab
From: Jan Kara <jack@suse.cz>
get_vaddr_frames() is used by relatively rare drivers so hide it and the
related functions behind a config option that is selected only by
drivers that need the infrastructure.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
create mode 100644 mm/frame_vector.c
diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
index 0a6780367d28..fc678289cf79 100644
--- a/drivers/gpu/drm/exynos/Kconfig
+++ b/drivers/gpu/drm/exynos/Kconfig
@@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
config DRM_EXYNOS_G2D
bool "Exynos DRM G2D"
depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
+ select FRAME_VECTOR
help
Choose this option if you want to use Exynos G2D for DRM.
diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
index dc2aaab54aef..217d613b0fe7 100644
--- a/drivers/media/platform/omap/Kconfig
+++ b/drivers/media/platform/omap/Kconfig
@@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
+ select FRAME_VECTOR
default n
---help---
V4L2 Display driver support for OMAP2/3 based boards.
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index f7a01a72eb9e..f38f6e387f04 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
config VIDEOBUF2_MEMOPS
tristate
+ select FRAME_VECTOR
config VIDEOBUF2_DMA_CONTIG
tristate
diff --git a/mm/Kconfig b/mm/Kconfig
index 390214da4546..2ca52e9986f0 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
changed to a smaller value in which case that is used.
A sane initial value is 80 MB.
+
+config FRAME_VECTOR
+ bool
diff --git a/mm/Makefile b/mm/Makefile
index 98c4eaeabdcb..be5d5c866305 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
+obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
new file mode 100644
index 000000000000..31a2bd5f41d5
--- /dev/null
+++ b/mm/frame_vector.c
@@ -0,0 +1,232 @@
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+
+/*
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @write: whether pages will be written to by the caller
+ * @force: whether to force write access even if user mapping is
+ * readonly. See description of the same argument of
+ get_user_pages().
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_sem as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ bool write, bool force, struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+ int locked;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ down_read(&mm->mmap_sem);
+ locked = 1;
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ ret = get_user_pages_locked(current, mm, start, nr_frames,
+ write, force, (struct page **)(vec->ptrs), &locked);
+ goto out;
+ }
+
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /*
+ * We stop if we have enough pages or if VMA doesn't completely
+ * cover the tail page.
+ */
+ if (ret >= nr_frames || start < vma->vm_end)
+ break;
+ vma = find_vma_intersection(mm, start, start + 1);
+ } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+out:
+ if (locked)
+ up_read(&mm->mmap_sem);
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ int i;
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+ for (i = 0; i < vec->nr_frames; i++)
+ put_page(pages[i]);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ if (size <= PAGE_SIZE)
+ vec = kmalloc(size, GFP_KERNEL);
+ else
+ vec = vmalloc(size);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ if (!is_vmalloc_addr(vec))
+ kfree(vec);
+ else
+ vfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
diff --git a/mm/gup.c b/mm/gup.c
index 9d7f4fde30cb..222d57e335f9 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
return ret; /* 0 or negative error code */
}
-/*
- * get_vaddr_frames() - map virtual addresses to pfns
- * @start: starting user address
- * @nr_frames: number of pages / pfns from start to map
- * @write: whether pages will be written to by the caller
- * @force: whether to force write access even if user mapping is
- * readonly. See description of the same argument of
- get_user_pages().
- * @vec: structure which receives pages / pfns of the addresses mapped.
- * It should have space for at least nr_frames entries.
- *
- * This function maps virtual addresses from @start and fills @vec structure
- * with page frame numbers or page pointers to corresponding pages (choice
- * depends on the type of the vma underlying the virtual address). If @start
- * belongs to a normal vma, the function grabs reference to each of the pages
- * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
- * touch page structures and the caller must make sure pfns aren't reused for
- * anything else while he is using them.
- *
- * The function returns number of pages mapped which may be less than
- * @nr_frames. In particular we stop mapping if there are more vmas of
- * different type underlying the specified range of virtual addresses.
- * When the function isn't able to map a single page, it returns error.
- *
- * This function takes care of grabbing mmap_sem as necessary.
- */
-int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
- bool write, bool force, struct frame_vector *vec)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int ret = 0;
- int err;
- int locked;
-
- if (nr_frames == 0)
- return 0;
-
- if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
- nr_frames = vec->nr_allocated;
-
- down_read(&mm->mmap_sem);
- locked = 1;
- vma = find_vma_intersection(mm, start, start + 1);
- if (!vma) {
- ret = -EFAULT;
- goto out;
- }
- if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
- vec->got_ref = true;
- vec->is_pfns = false;
- ret = get_user_pages_locked(current, mm, start, nr_frames,
- write, force, (struct page **)(vec->ptrs), &locked);
- goto out;
- }
-
- vec->got_ref = false;
- vec->is_pfns = true;
- do {
- unsigned long *nums = frame_vector_pfns(vec);
-
- while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
- err = follow_pfn(vma, start, &nums[ret]);
- if (err) {
- if (ret == 0)
- ret = err;
- goto out;
- }
- start += PAGE_SIZE;
- ret++;
- }
- /*
- * We stop if we have enough pages or if VMA doesn't completely
- * cover the tail page.
- */
- if (ret >= nr_frames || start < vma->vm_end)
- break;
- vma = find_vma_intersection(mm, start, start + 1);
- } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
-out:
- if (locked)
- up_read(&mm->mmap_sem);
- if (!ret)
- ret = -EFAULT;
- if (ret > 0)
- vec->nr_frames = ret;
- return ret;
-}
-EXPORT_SYMBOL(get_vaddr_frames);
-
-/**
- * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
- * them
- * @vec: frame vector to put
- *
- * Drop references to pages if get_vaddr_frames() acquired them. We also
- * invalidate the frame vector so that it is prepared for the next call into
- * get_vaddr_frames().
- */
-void put_vaddr_frames(struct frame_vector *vec)
-{
- int i;
- struct page **pages;
-
- if (!vec->got_ref)
- goto out;
- pages = frame_vector_pages(vec);
- /*
- * frame_vector_pages() might needed to do a conversion when
- * get_vaddr_frames() got pages but vec was later converted to pfns.
- * But it shouldn't really fail to convert pfns back...
- */
- if (WARN_ON(IS_ERR(pages)))
- goto out;
- for (i = 0; i < vec->nr_frames; i++)
- put_page(pages[i]);
- vec->got_ref = false;
-out:
- vec->nr_frames = 0;
-}
-EXPORT_SYMBOL(put_vaddr_frames);
-
-/**
- * frame_vector_to_pages - convert frame vector to contain page pointers
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of page pointers. If the conversion is
- * successful, return 0. Otherwise return an error. Note that we do not grab
- * page references for the page structures.
- */
-int frame_vector_to_pages(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (!vec->is_pfns)
- return 0;
- nums = frame_vector_pfns(vec);
- for (i = 0; i < vec->nr_frames; i++)
- if (!pfn_valid(nums[i]))
- return -EINVAL;
- pages = (struct page **)nums;
- for (i = 0; i < vec->nr_frames; i++)
- pages[i] = pfn_to_page(nums[i]);
- vec->is_pfns = false;
- return 0;
-}
-EXPORT_SYMBOL(frame_vector_to_pages);
-
-/**
- * frame_vector_to_pfns - convert frame vector to contain pfns
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of pfns.
- */
-void frame_vector_to_pfns(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (vec->is_pfns)
- return;
- pages = (struct page **)(vec->ptrs);
- nums = (unsigned long *)pages;
- for (i = 0; i < vec->nr_frames; i++)
- nums[i] = page_to_pfn(pages[i]);
- vec->is_pfns = true;
-}
-EXPORT_SYMBOL(frame_vector_to_pfns);
-
-/**
- * frame_vector_create() - allocate & initialize structure for pinned pfns
- * @nr_frames: number of pfns slots we should reserve
- *
- * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
- * pfns.
- */
-struct frame_vector *frame_vector_create(unsigned int nr_frames)
-{
- struct frame_vector *vec;
- int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
-
- if (WARN_ON_ONCE(nr_frames == 0))
- return NULL;
- /*
- * This is absurdly high. It's here just to avoid strange effects when
- * arithmetics overflows.
- */
- if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
- return NULL;
- /*
- * Avoid higher order allocations, use vmalloc instead. It should
- * be rare anyway.
- */
- if (size <= PAGE_SIZE)
- vec = kmalloc(size, GFP_KERNEL);
- else
- vec = vmalloc(size);
- if (!vec)
- return NULL;
- vec->nr_allocated = nr_frames;
- vec->nr_frames = 0;
- return vec;
-}
-EXPORT_SYMBOL(frame_vector_create);
-
-/**
- * frame_vector_destroy() - free memory allocated to carry frame vector
- * @vec: Frame vector to free
- *
- * Free structure allocated by frame_vector_create() to carry frames.
- */
-void frame_vector_destroy(struct frame_vector *vec)
-{
- /* Make sure put_vaddr_frames() got called properly... */
- VM_BUG_ON(vec->nr_frames > 0);
- if (!is_vmalloc_addr(vec))
- kfree(vec);
- else
- vfree(vec);
-}
-EXPORT_SYMBOL(frame_vector_destroy);
-
/**
* get_dump_page() - pin user page in memory while writing it to core dump
* @addr: user address
--
2.4.2
--
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^ permalink raw reply related [flat|nested] 35+ messages in thread* [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-10 9:20 ` Mauro Carvalho Chehab
0 siblings, 0 replies; 35+ messages in thread
From: Mauro Carvalho Chehab @ 2015-06-10 9:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Jan Kara, Linux Media Mailing List, Mauro Carvalho Chehab,
Inki Dae, Joonyoung Shim, Seung-Woo Kim, Kyungmin Park,
David Airlie, Kukjin Kim, Hans Verkuil, Paul Bolle, Randy Dunlap,
Jiri Kosina, Geert Uytterhoeven, Mark Brown, Dan Streetman,
Joonsoo Kim, Minchan Kim, Paul E. McKenney, Steve Capper,
Sasha Levin, Ganesh Mahendran, Christoph Jaeger
From: Jan Kara <jack@suse.cz>
get_vaddr_frames() is used by relatively rare drivers so hide it and the
related functions behind a config option that is selected only by
drivers that need the infrastructure.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
create mode 100644 mm/frame_vector.c
diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
index 0a6780367d28..fc678289cf79 100644
--- a/drivers/gpu/drm/exynos/Kconfig
+++ b/drivers/gpu/drm/exynos/Kconfig
@@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
config DRM_EXYNOS_G2D
bool "Exynos DRM G2D"
depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
+ select FRAME_VECTOR
help
Choose this option if you want to use Exynos G2D for DRM.
diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
index dc2aaab54aef..217d613b0fe7 100644
--- a/drivers/media/platform/omap/Kconfig
+++ b/drivers/media/platform/omap/Kconfig
@@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
+ select FRAME_VECTOR
default n
---help---
V4L2 Display driver support for OMAP2/3 based boards.
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index f7a01a72eb9e..f38f6e387f04 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
config VIDEOBUF2_MEMOPS
tristate
+ select FRAME_VECTOR
config VIDEOBUF2_DMA_CONTIG
tristate
diff --git a/mm/Kconfig b/mm/Kconfig
index 390214da4546..2ca52e9986f0 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
changed to a smaller value in which case that is used.
A sane initial value is 80 MB.
+
+config FRAME_VECTOR
+ bool
diff --git a/mm/Makefile b/mm/Makefile
index 98c4eaeabdcb..be5d5c866305 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
+obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
new file mode 100644
index 000000000000..31a2bd5f41d5
--- /dev/null
+++ b/mm/frame_vector.c
@@ -0,0 +1,232 @@
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+
+/*
+ * get_vaddr_frames() - map virtual addresses to pfns
+ * @start: starting user address
+ * @nr_frames: number of pages / pfns from start to map
+ * @write: whether pages will be written to by the caller
+ * @force: whether to force write access even if user mapping is
+ * readonly. See description of the same argument of
+ get_user_pages().
+ * @vec: structure which receives pages / pfns of the addresses mapped.
+ * It should have space for at least nr_frames entries.
+ *
+ * This function maps virtual addresses from @start and fills @vec structure
+ * with page frame numbers or page pointers to corresponding pages (choice
+ * depends on the type of the vma underlying the virtual address). If @start
+ * belongs to a normal vma, the function grabs reference to each of the pages
+ * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
+ * touch page structures and the caller must make sure pfns aren't reused for
+ * anything else while he is using them.
+ *
+ * The function returns number of pages mapped which may be less than
+ * @nr_frames. In particular we stop mapping if there are more vmas of
+ * different type underlying the specified range of virtual addresses.
+ * When the function isn't able to map a single page, it returns error.
+ *
+ * This function takes care of grabbing mmap_sem as necessary.
+ */
+int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
+ bool write, bool force, struct frame_vector *vec)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int ret = 0;
+ int err;
+ int locked;
+
+ if (nr_frames == 0)
+ return 0;
+
+ if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
+ nr_frames = vec->nr_allocated;
+
+ down_read(&mm->mmap_sem);
+ locked = 1;
+ vma = find_vma_intersection(mm, start, start + 1);
+ if (!vma) {
+ ret = -EFAULT;
+ goto out;
+ }
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
+ vec->got_ref = true;
+ vec->is_pfns = false;
+ ret = get_user_pages_locked(current, mm, start, nr_frames,
+ write, force, (struct page **)(vec->ptrs), &locked);
+ goto out;
+ }
+
+ vec->got_ref = false;
+ vec->is_pfns = true;
+ do {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
+ err = follow_pfn(vma, start, &nums[ret]);
+ if (err) {
+ if (ret == 0)
+ ret = err;
+ goto out;
+ }
+ start += PAGE_SIZE;
+ ret++;
+ }
+ /*
+ * We stop if we have enough pages or if VMA doesn't completely
+ * cover the tail page.
+ */
+ if (ret >= nr_frames || start < vma->vm_end)
+ break;
+ vma = find_vma_intersection(mm, start, start + 1);
+ } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+out:
+ if (locked)
+ up_read(&mm->mmap_sem);
+ if (!ret)
+ ret = -EFAULT;
+ if (ret > 0)
+ vec->nr_frames = ret;
+ return ret;
+}
+EXPORT_SYMBOL(get_vaddr_frames);
+
+/**
+ * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
+ * them
+ * @vec: frame vector to put
+ *
+ * Drop references to pages if get_vaddr_frames() acquired them. We also
+ * invalidate the frame vector so that it is prepared for the next call into
+ * get_vaddr_frames().
+ */
+void put_vaddr_frames(struct frame_vector *vec)
+{
+ int i;
+ struct page **pages;
+
+ if (!vec->got_ref)
+ goto out;
+ pages = frame_vector_pages(vec);
+ /*
+ * frame_vector_pages() might needed to do a conversion when
+ * get_vaddr_frames() got pages but vec was later converted to pfns.
+ * But it shouldn't really fail to convert pfns back...
+ */
+ if (WARN_ON(IS_ERR(pages)))
+ goto out;
+ for (i = 0; i < vec->nr_frames; i++)
+ put_page(pages[i]);
+ vec->got_ref = false;
+out:
+ vec->nr_frames = 0;
+}
+EXPORT_SYMBOL(put_vaddr_frames);
+
+/**
+ * frame_vector_to_pages - convert frame vector to contain page pointers
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of page pointers. If the conversion is
+ * successful, return 0. Otherwise return an error. Note that we do not grab
+ * page references for the page structures.
+ */
+int frame_vector_to_pages(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (!vec->is_pfns)
+ return 0;
+ nums = frame_vector_pfns(vec);
+ for (i = 0; i < vec->nr_frames; i++)
+ if (!pfn_valid(nums[i]))
+ return -EINVAL;
+ pages = (struct page **)nums;
+ for (i = 0; i < vec->nr_frames; i++)
+ pages[i] = pfn_to_page(nums[i]);
+ vec->is_pfns = false;
+ return 0;
+}
+EXPORT_SYMBOL(frame_vector_to_pages);
+
+/**
+ * frame_vector_to_pfns - convert frame vector to contain pfns
+ * @vec: frame vector to convert
+ *
+ * Convert @vec to contain array of pfns.
+ */
+void frame_vector_to_pfns(struct frame_vector *vec)
+{
+ int i;
+ unsigned long *nums;
+ struct page **pages;
+
+ if (vec->is_pfns)
+ return;
+ pages = (struct page **)(vec->ptrs);
+ nums = (unsigned long *)pages;
+ for (i = 0; i < vec->nr_frames; i++)
+ nums[i] = page_to_pfn(pages[i]);
+ vec->is_pfns = true;
+}
+EXPORT_SYMBOL(frame_vector_to_pfns);
+
+/**
+ * frame_vector_create() - allocate & initialize structure for pinned pfns
+ * @nr_frames: number of pfns slots we should reserve
+ *
+ * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
+ * pfns.
+ */
+struct frame_vector *frame_vector_create(unsigned int nr_frames)
+{
+ struct frame_vector *vec;
+ int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
+
+ if (WARN_ON_ONCE(nr_frames == 0))
+ return NULL;
+ /*
+ * This is absurdly high. It's here just to avoid strange effects when
+ * arithmetics overflows.
+ */
+ if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
+ return NULL;
+ /*
+ * Avoid higher order allocations, use vmalloc instead. It should
+ * be rare anyway.
+ */
+ if (size <= PAGE_SIZE)
+ vec = kmalloc(size, GFP_KERNEL);
+ else
+ vec = vmalloc(size);
+ if (!vec)
+ return NULL;
+ vec->nr_allocated = nr_frames;
+ vec->nr_frames = 0;
+ return vec;
+}
+EXPORT_SYMBOL(frame_vector_create);
+
+/**
+ * frame_vector_destroy() - free memory allocated to carry frame vector
+ * @vec: Frame vector to free
+ *
+ * Free structure allocated by frame_vector_create() to carry frames.
+ */
+void frame_vector_destroy(struct frame_vector *vec)
+{
+ /* Make sure put_vaddr_frames() got called properly... */
+ VM_BUG_ON(vec->nr_frames > 0);
+ if (!is_vmalloc_addr(vec))
+ kfree(vec);
+ else
+ vfree(vec);
+}
+EXPORT_SYMBOL(frame_vector_destroy);
diff --git a/mm/gup.c b/mm/gup.c
index 9d7f4fde30cb..222d57e335f9 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
return ret; /* 0 or negative error code */
}
-/*
- * get_vaddr_frames() - map virtual addresses to pfns
- * @start: starting user address
- * @nr_frames: number of pages / pfns from start to map
- * @write: whether pages will be written to by the caller
- * @force: whether to force write access even if user mapping is
- * readonly. See description of the same argument of
- get_user_pages().
- * @vec: structure which receives pages / pfns of the addresses mapped.
- * It should have space for at least nr_frames entries.
- *
- * This function maps virtual addresses from @start and fills @vec structure
- * with page frame numbers or page pointers to corresponding pages (choice
- * depends on the type of the vma underlying the virtual address). If @start
- * belongs to a normal vma, the function grabs reference to each of the pages
- * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
- * touch page structures and the caller must make sure pfns aren't reused for
- * anything else while he is using them.
- *
- * The function returns number of pages mapped which may be less than
- * @nr_frames. In particular we stop mapping if there are more vmas of
- * different type underlying the specified range of virtual addresses.
- * When the function isn't able to map a single page, it returns error.
- *
- * This function takes care of grabbing mmap_sem as necessary.
- */
-int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
- bool write, bool force, struct frame_vector *vec)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int ret = 0;
- int err;
- int locked;
-
- if (nr_frames == 0)
- return 0;
-
- if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
- nr_frames = vec->nr_allocated;
-
- down_read(&mm->mmap_sem);
- locked = 1;
- vma = find_vma_intersection(mm, start, start + 1);
- if (!vma) {
- ret = -EFAULT;
- goto out;
- }
- if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
- vec->got_ref = true;
- vec->is_pfns = false;
- ret = get_user_pages_locked(current, mm, start, nr_frames,
- write, force, (struct page **)(vec->ptrs), &locked);
- goto out;
- }
-
- vec->got_ref = false;
- vec->is_pfns = true;
- do {
- unsigned long *nums = frame_vector_pfns(vec);
-
- while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
- err = follow_pfn(vma, start, &nums[ret]);
- if (err) {
- if (ret == 0)
- ret = err;
- goto out;
- }
- start += PAGE_SIZE;
- ret++;
- }
- /*
- * We stop if we have enough pages or if VMA doesn't completely
- * cover the tail page.
- */
- if (ret >= nr_frames || start < vma->vm_end)
- break;
- vma = find_vma_intersection(mm, start, start + 1);
- } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
-out:
- if (locked)
- up_read(&mm->mmap_sem);
- if (!ret)
- ret = -EFAULT;
- if (ret > 0)
- vec->nr_frames = ret;
- return ret;
-}
-EXPORT_SYMBOL(get_vaddr_frames);
-
-/**
- * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
- * them
- * @vec: frame vector to put
- *
- * Drop references to pages if get_vaddr_frames() acquired them. We also
- * invalidate the frame vector so that it is prepared for the next call into
- * get_vaddr_frames().
- */
-void put_vaddr_frames(struct frame_vector *vec)
-{
- int i;
- struct page **pages;
-
- if (!vec->got_ref)
- goto out;
- pages = frame_vector_pages(vec);
- /*
- * frame_vector_pages() might needed to do a conversion when
- * get_vaddr_frames() got pages but vec was later converted to pfns.
- * But it shouldn't really fail to convert pfns back...
- */
- if (WARN_ON(IS_ERR(pages)))
- goto out;
- for (i = 0; i < vec->nr_frames; i++)
- put_page(pages[i]);
- vec->got_ref = false;
-out:
- vec->nr_frames = 0;
-}
-EXPORT_SYMBOL(put_vaddr_frames);
-
-/**
- * frame_vector_to_pages - convert frame vector to contain page pointers
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of page pointers. If the conversion is
- * successful, return 0. Otherwise return an error. Note that we do not grab
- * page references for the page structures.
- */
-int frame_vector_to_pages(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (!vec->is_pfns)
- return 0;
- nums = frame_vector_pfns(vec);
- for (i = 0; i < vec->nr_frames; i++)
- if (!pfn_valid(nums[i]))
- return -EINVAL;
- pages = (struct page **)nums;
- for (i = 0; i < vec->nr_frames; i++)
- pages[i] = pfn_to_page(nums[i]);
- vec->is_pfns = false;
- return 0;
-}
-EXPORT_SYMBOL(frame_vector_to_pages);
-
-/**
- * frame_vector_to_pfns - convert frame vector to contain pfns
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of pfns.
- */
-void frame_vector_to_pfns(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (vec->is_pfns)
- return;
- pages = (struct page **)(vec->ptrs);
- nums = (unsigned long *)pages;
- for (i = 0; i < vec->nr_frames; i++)
- nums[i] = page_to_pfn(pages[i]);
- vec->is_pfns = true;
-}
-EXPORT_SYMBOL(frame_vector_to_pfns);
-
-/**
- * frame_vector_create() - allocate & initialize structure for pinned pfns
- * @nr_frames: number of pfns slots we should reserve
- *
- * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
- * pfns.
- */
-struct frame_vector *frame_vector_create(unsigned int nr_frames)
-{
- struct frame_vector *vec;
- int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
-
- if (WARN_ON_ONCE(nr_frames == 0))
- return NULL;
- /*
- * This is absurdly high. It's here just to avoid strange effects when
- * arithmetics overflows.
- */
- if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
- return NULL;
- /*
- * Avoid higher order allocations, use vmalloc instead. It should
- * be rare anyway.
- */
- if (size <= PAGE_SIZE)
- vec = kmalloc(size, GFP_KERNEL);
- else
- vec = vmalloc(size);
- if (!vec)
- return NULL;
- vec->nr_allocated = nr_frames;
- vec->nr_frames = 0;
- return vec;
-}
-EXPORT_SYMBOL(frame_vector_create);
-
-/**
- * frame_vector_destroy() - free memory allocated to carry frame vector
- * @vec: Frame vector to free
- *
- * Free structure allocated by frame_vector_create() to carry frames.
- */
-void frame_vector_destroy(struct frame_vector *vec)
-{
- /* Make sure put_vaddr_frames() got called properly... */
- VM_BUG_ON(vec->nr_frames > 0);
- if (!is_vmalloc_addr(vec))
- kfree(vec);
- else
- vfree(vec);
-}
-EXPORT_SYMBOL(frame_vector_destroy);
-
/**
* get_dump_page() - pin user page in memory while writing it to core dump
* @addr: user address
--
2.4.2
^ permalink raw reply related [flat|nested] 35+ messages in thread* Re: [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
2015-06-10 9:20 ` Mauro Carvalho Chehab
(?)
(?)
@ 2015-06-10 16:37 ` Josh Triplett
-1 siblings, 0 replies; 35+ messages in thread
From: Josh Triplett @ 2015-06-10 16:37 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Inki Dae, Joonyoung Shim, Seung-Woo Kim,
Kyungmin Park, David Airlie, Kukjin Kim, Hans Verkuil,
Paul Bolle, Randy Dunlap, Jiri Kosina, Geert Uytterhoeven,
Mark Brown, Dan Streetman, Joonsoo Kim, Minchan Kim,
Paul E. McKenney, Steve Capper, Sasha Levin, Ganesh Mahendran,
Christoph Jaeger, Michal Hocko, Johannes Weiner, Andrey Ryabinin,
Konstantin Khlebnikov, Matthew Wilcox, Al Viro,
Kirill A. Shutemov, Christian Borntraeger, Andrea Arcangeli,
Paul Cassella, Aneesh Kumar K.V, Naoya Horiguchi, dri-devel,
linux-arm-kernel, linux-samsung-soc, linux-mm
On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> From: Jan Kara <jack@suse.cz>
>
> get_vaddr_frames() is used by relatively rare drivers so hide it and the
> related functions behind a config option that is selected only by
> drivers that need the infrastructure.
>
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
>
> Signed-off-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Seems sensible to me.
Since this patch makes the kernel smaller, can you include the delta
from bloat-o-meter between allnoconfig with and without this patch?
Also, I assume you've compile-tested the kernel with allyesconfig minus
the three options that now have "select FRAME_VECTOR", to make sure it
builds?
> create mode 100644 mm/frame_vector.c
>
> diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> index 0a6780367d28..fc678289cf79 100644
> --- a/drivers/gpu/drm/exynos/Kconfig
> +++ b/drivers/gpu/drm/exynos/Kconfig
> @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> config DRM_EXYNOS_G2D
> bool "Exynos DRM G2D"
> depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> + select FRAME_VECTOR
> help
> Choose this option if you want to use Exynos G2D for DRM.
>
> diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> index dc2aaab54aef..217d613b0fe7 100644
> --- a/drivers/media/platform/omap/Kconfig
> +++ b/drivers/media/platform/omap/Kconfig
> @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> + select FRAME_VECTOR
> default n
> ---help---
> V4L2 Display driver support for OMAP2/3 based boards.
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index f7a01a72eb9e..f38f6e387f04 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
>
> config VIDEOBUF2_MEMOPS
> tristate
> + select FRAME_VECTOR
>
> config VIDEOBUF2_DMA_CONTIG
> tristate
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 390214da4546..2ca52e9986f0 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> changed to a smaller value in which case that is used.
>
> A sane initial value is 80 MB.
> +
> +config FRAME_VECTOR
> + bool
> diff --git a/mm/Makefile b/mm/Makefile
> index 98c4eaeabdcb..be5d5c866305 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> new file mode 100644
> index 000000000000..31a2bd5f41d5
> --- /dev/null
> +++ b/mm/frame_vector.c
> @@ -0,0 +1,232 @@
> +#include <linux/kernel.h>
> +#include <linux/errno.h>
> +#include <linux/err.h>
> +#include <linux/mm.h>
> +#include <linux/slab.h>
> +#include <linux/pagemap.h>
> +#include <linux/sched.h>
> +
> +/*
> + * get_vaddr_frames() - map virtual addresses to pfns
> + * @start: starting user address
> + * @nr_frames: number of pages / pfns from start to map
> + * @write: whether pages will be written to by the caller
> + * @force: whether to force write access even if user mapping is
> + * readonly. See description of the same argument of
> + get_user_pages().
> + * @vec: structure which receives pages / pfns of the addresses mapped.
> + * It should have space for at least nr_frames entries.
> + *
> + * This function maps virtual addresses from @start and fills @vec structure
> + * with page frame numbers or page pointers to corresponding pages (choice
> + * depends on the type of the vma underlying the virtual address). If @start
> + * belongs to a normal vma, the function grabs reference to each of the pages
> + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> + * touch page structures and the caller must make sure pfns aren't reused for
> + * anything else while he is using them.
> + *
> + * The function returns number of pages mapped which may be less than
> + * @nr_frames. In particular we stop mapping if there are more vmas of
> + * different type underlying the specified range of virtual addresses.
> + * When the function isn't able to map a single page, it returns error.
> + *
> + * This function takes care of grabbing mmap_sem as necessary.
> + */
> +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> + bool write, bool force, struct frame_vector *vec)
> +{
> + struct mm_struct *mm = current->mm;
> + struct vm_area_struct *vma;
> + int ret = 0;
> + int err;
> + int locked;
> +
> + if (nr_frames == 0)
> + return 0;
> +
> + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> + nr_frames = vec->nr_allocated;
> +
> + down_read(&mm->mmap_sem);
> + locked = 1;
> + vma = find_vma_intersection(mm, start, start + 1);
> + if (!vma) {
> + ret = -EFAULT;
> + goto out;
> + }
> + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> + vec->got_ref = true;
> + vec->is_pfns = false;
> + ret = get_user_pages_locked(current, mm, start, nr_frames,
> + write, force, (struct page **)(vec->ptrs), &locked);
> + goto out;
> + }
> +
> + vec->got_ref = false;
> + vec->is_pfns = true;
> + do {
> + unsigned long *nums = frame_vector_pfns(vec);
> +
> + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> + err = follow_pfn(vma, start, &nums[ret]);
> + if (err) {
> + if (ret == 0)
> + ret = err;
> + goto out;
> + }
> + start += PAGE_SIZE;
> + ret++;
> + }
> + /*
> + * We stop if we have enough pages or if VMA doesn't completely
> + * cover the tail page.
> + */
> + if (ret >= nr_frames || start < vma->vm_end)
> + break;
> + vma = find_vma_intersection(mm, start, start + 1);
> + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> +out:
> + if (locked)
> + up_read(&mm->mmap_sem);
> + if (!ret)
> + ret = -EFAULT;
> + if (ret > 0)
> + vec->nr_frames = ret;
> + return ret;
> +}
> +EXPORT_SYMBOL(get_vaddr_frames);
> +
> +/**
> + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> + * them
> + * @vec: frame vector to put
> + *
> + * Drop references to pages if get_vaddr_frames() acquired them. We also
> + * invalidate the frame vector so that it is prepared for the next call into
> + * get_vaddr_frames().
> + */
> +void put_vaddr_frames(struct frame_vector *vec)
> +{
> + int i;
> + struct page **pages;
> +
> + if (!vec->got_ref)
> + goto out;
> + pages = frame_vector_pages(vec);
> + /*
> + * frame_vector_pages() might needed to do a conversion when
> + * get_vaddr_frames() got pages but vec was later converted to pfns.
> + * But it shouldn't really fail to convert pfns back...
> + */
> + if (WARN_ON(IS_ERR(pages)))
> + goto out;
> + for (i = 0; i < vec->nr_frames; i++)
> + put_page(pages[i]);
> + vec->got_ref = false;
> +out:
> + vec->nr_frames = 0;
> +}
> +EXPORT_SYMBOL(put_vaddr_frames);
> +
> +/**
> + * frame_vector_to_pages - convert frame vector to contain page pointers
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of page pointers. If the conversion is
> + * successful, return 0. Otherwise return an error. Note that we do not grab
> + * page references for the page structures.
> + */
> +int frame_vector_to_pages(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (!vec->is_pfns)
> + return 0;
> + nums = frame_vector_pfns(vec);
> + for (i = 0; i < vec->nr_frames; i++)
> + if (!pfn_valid(nums[i]))
> + return -EINVAL;
> + pages = (struct page **)nums;
> + for (i = 0; i < vec->nr_frames; i++)
> + pages[i] = pfn_to_page(nums[i]);
> + vec->is_pfns = false;
> + return 0;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pages);
> +
> +/**
> + * frame_vector_to_pfns - convert frame vector to contain pfns
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of pfns.
> + */
> +void frame_vector_to_pfns(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (vec->is_pfns)
> + return;
> + pages = (struct page **)(vec->ptrs);
> + nums = (unsigned long *)pages;
> + for (i = 0; i < vec->nr_frames; i++)
> + nums[i] = page_to_pfn(pages[i]);
> + vec->is_pfns = true;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pfns);
> +
> +/**
> + * frame_vector_create() - allocate & initialize structure for pinned pfns
> + * @nr_frames: number of pfns slots we should reserve
> + *
> + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> + * pfns.
> + */
> +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> +{
> + struct frame_vector *vec;
> + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> +
> + if (WARN_ON_ONCE(nr_frames == 0))
> + return NULL;
> + /*
> + * This is absurdly high. It's here just to avoid strange effects when
> + * arithmetics overflows.
> + */
> + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> + return NULL;
> + /*
> + * Avoid higher order allocations, use vmalloc instead. It should
> + * be rare anyway.
> + */
> + if (size <= PAGE_SIZE)
> + vec = kmalloc(size, GFP_KERNEL);
> + else
> + vec = vmalloc(size);
> + if (!vec)
> + return NULL;
> + vec->nr_allocated = nr_frames;
> + vec->nr_frames = 0;
> + return vec;
> +}
> +EXPORT_SYMBOL(frame_vector_create);
> +
> +/**
> + * frame_vector_destroy() - free memory allocated to carry frame vector
> + * @vec: Frame vector to free
> + *
> + * Free structure allocated by frame_vector_create() to carry frames.
> + */
> +void frame_vector_destroy(struct frame_vector *vec)
> +{
> + /* Make sure put_vaddr_frames() got called properly... */
> + VM_BUG_ON(vec->nr_frames > 0);
> + if (!is_vmalloc_addr(vec))
> + kfree(vec);
> + else
> + vfree(vec);
> +}
> +EXPORT_SYMBOL(frame_vector_destroy);
> diff --git a/mm/gup.c b/mm/gup.c
> index 9d7f4fde30cb..222d57e335f9 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> return ret; /* 0 or negative error code */
> }
>
> -/*
> - * get_vaddr_frames() - map virtual addresses to pfns
> - * @start: starting user address
> - * @nr_frames: number of pages / pfns from start to map
> - * @write: whether pages will be written to by the caller
> - * @force: whether to force write access even if user mapping is
> - * readonly. See description of the same argument of
> - get_user_pages().
> - * @vec: structure which receives pages / pfns of the addresses mapped.
> - * It should have space for at least nr_frames entries.
> - *
> - * This function maps virtual addresses from @start and fills @vec structure
> - * with page frame numbers or page pointers to corresponding pages (choice
> - * depends on the type of the vma underlying the virtual address). If @start
> - * belongs to a normal vma, the function grabs reference to each of the pages
> - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> - * touch page structures and the caller must make sure pfns aren't reused for
> - * anything else while he is using them.
> - *
> - * The function returns number of pages mapped which may be less than
> - * @nr_frames. In particular we stop mapping if there are more vmas of
> - * different type underlying the specified range of virtual addresses.
> - * When the function isn't able to map a single page, it returns error.
> - *
> - * This function takes care of grabbing mmap_sem as necessary.
> - */
> -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> - bool write, bool force, struct frame_vector *vec)
> -{
> - struct mm_struct *mm = current->mm;
> - struct vm_area_struct *vma;
> - int ret = 0;
> - int err;
> - int locked;
> -
> - if (nr_frames == 0)
> - return 0;
> -
> - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> - nr_frames = vec->nr_allocated;
> -
> - down_read(&mm->mmap_sem);
> - locked = 1;
> - vma = find_vma_intersection(mm, start, start + 1);
> - if (!vma) {
> - ret = -EFAULT;
> - goto out;
> - }
> - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> - vec->got_ref = true;
> - vec->is_pfns = false;
> - ret = get_user_pages_locked(current, mm, start, nr_frames,
> - write, force, (struct page **)(vec->ptrs), &locked);
> - goto out;
> - }
> -
> - vec->got_ref = false;
> - vec->is_pfns = true;
> - do {
> - unsigned long *nums = frame_vector_pfns(vec);
> -
> - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> - err = follow_pfn(vma, start, &nums[ret]);
> - if (err) {
> - if (ret == 0)
> - ret = err;
> - goto out;
> - }
> - start += PAGE_SIZE;
> - ret++;
> - }
> - /*
> - * We stop if we have enough pages or if VMA doesn't completely
> - * cover the tail page.
> - */
> - if (ret >= nr_frames || start < vma->vm_end)
> - break;
> - vma = find_vma_intersection(mm, start, start + 1);
> - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> -out:
> - if (locked)
> - up_read(&mm->mmap_sem);
> - if (!ret)
> - ret = -EFAULT;
> - if (ret > 0)
> - vec->nr_frames = ret;
> - return ret;
> -}
> -EXPORT_SYMBOL(get_vaddr_frames);
> -
> -/**
> - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> - * them
> - * @vec: frame vector to put
> - *
> - * Drop references to pages if get_vaddr_frames() acquired them. We also
> - * invalidate the frame vector so that it is prepared for the next call into
> - * get_vaddr_frames().
> - */
> -void put_vaddr_frames(struct frame_vector *vec)
> -{
> - int i;
> - struct page **pages;
> -
> - if (!vec->got_ref)
> - goto out;
> - pages = frame_vector_pages(vec);
> - /*
> - * frame_vector_pages() might needed to do a conversion when
> - * get_vaddr_frames() got pages but vec was later converted to pfns.
> - * But it shouldn't really fail to convert pfns back...
> - */
> - if (WARN_ON(IS_ERR(pages)))
> - goto out;
> - for (i = 0; i < vec->nr_frames; i++)
> - put_page(pages[i]);
> - vec->got_ref = false;
> -out:
> - vec->nr_frames = 0;
> -}
> -EXPORT_SYMBOL(put_vaddr_frames);
> -
> -/**
> - * frame_vector_to_pages - convert frame vector to contain page pointers
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of page pointers. If the conversion is
> - * successful, return 0. Otherwise return an error. Note that we do not grab
> - * page references for the page structures.
> - */
> -int frame_vector_to_pages(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (!vec->is_pfns)
> - return 0;
> - nums = frame_vector_pfns(vec);
> - for (i = 0; i < vec->nr_frames; i++)
> - if (!pfn_valid(nums[i]))
> - return -EINVAL;
> - pages = (struct page **)nums;
> - for (i = 0; i < vec->nr_frames; i++)
> - pages[i] = pfn_to_page(nums[i]);
> - vec->is_pfns = false;
> - return 0;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pages);
> -
> -/**
> - * frame_vector_to_pfns - convert frame vector to contain pfns
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of pfns.
> - */
> -void frame_vector_to_pfns(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (vec->is_pfns)
> - return;
> - pages = (struct page **)(vec->ptrs);
> - nums = (unsigned long *)pages;
> - for (i = 0; i < vec->nr_frames; i++)
> - nums[i] = page_to_pfn(pages[i]);
> - vec->is_pfns = true;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pfns);
> -
> -/**
> - * frame_vector_create() - allocate & initialize structure for pinned pfns
> - * @nr_frames: number of pfns slots we should reserve
> - *
> - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> - * pfns.
> - */
> -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> -{
> - struct frame_vector *vec;
> - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> -
> - if (WARN_ON_ONCE(nr_frames == 0))
> - return NULL;
> - /*
> - * This is absurdly high. It's here just to avoid strange effects when
> - * arithmetics overflows.
> - */
> - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> - return NULL;
> - /*
> - * Avoid higher order allocations, use vmalloc instead. It should
> - * be rare anyway.
> - */
> - if (size <= PAGE_SIZE)
> - vec = kmalloc(size, GFP_KERNEL);
> - else
> - vec = vmalloc(size);
> - if (!vec)
> - return NULL;
> - vec->nr_allocated = nr_frames;
> - vec->nr_frames = 0;
> - return vec;
> -}
> -EXPORT_SYMBOL(frame_vector_create);
> -
> -/**
> - * frame_vector_destroy() - free memory allocated to carry frame vector
> - * @vec: Frame vector to free
> - *
> - * Free structure allocated by frame_vector_create() to carry frames.
> - */
> -void frame_vector_destroy(struct frame_vector *vec)
> -{
> - /* Make sure put_vaddr_frames() got called properly... */
> - VM_BUG_ON(vec->nr_frames > 0);
> - if (!is_vmalloc_addr(vec))
> - kfree(vec);
> - else
> - vfree(vec);
> -}
> -EXPORT_SYMBOL(frame_vector_destroy);
> -
> /**
> * get_dump_page() - pin user page in memory while writing it to core dump
> * @addr: user address
> --
> 2.4.2
>
^ permalink raw reply [flat|nested] 35+ messages in thread* [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-10 16:37 ` Josh Triplett
0 siblings, 0 replies; 35+ messages in thread
From: Josh Triplett @ 2015-06-10 16:37 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> From: Jan Kara <jack@suse.cz>
>
> get_vaddr_frames() is used by relatively rare drivers so hide it and the
> related functions behind a config option that is selected only by
> drivers that need the infrastructure.
>
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
>
> Signed-off-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Seems sensible to me.
Since this patch makes the kernel smaller, can you include the delta
from bloat-o-meter between allnoconfig with and without this patch?
Also, I assume you've compile-tested the kernel with allyesconfig minus
the three options that now have "select FRAME_VECTOR", to make sure it
builds?
> create mode 100644 mm/frame_vector.c
>
> diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> index 0a6780367d28..fc678289cf79 100644
> --- a/drivers/gpu/drm/exynos/Kconfig
> +++ b/drivers/gpu/drm/exynos/Kconfig
> @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> config DRM_EXYNOS_G2D
> bool "Exynos DRM G2D"
> depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> + select FRAME_VECTOR
> help
> Choose this option if you want to use Exynos G2D for DRM.
>
> diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> index dc2aaab54aef..217d613b0fe7 100644
> --- a/drivers/media/platform/omap/Kconfig
> +++ b/drivers/media/platform/omap/Kconfig
> @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> + select FRAME_VECTOR
> default n
> ---help---
> V4L2 Display driver support for OMAP2/3 based boards.
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index f7a01a72eb9e..f38f6e387f04 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
>
> config VIDEOBUF2_MEMOPS
> tristate
> + select FRAME_VECTOR
>
> config VIDEOBUF2_DMA_CONTIG
> tristate
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 390214da4546..2ca52e9986f0 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> changed to a smaller value in which case that is used.
>
> A sane initial value is 80 MB.
> +
> +config FRAME_VECTOR
> + bool
> diff --git a/mm/Makefile b/mm/Makefile
> index 98c4eaeabdcb..be5d5c866305 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> new file mode 100644
> index 000000000000..31a2bd5f41d5
> --- /dev/null
> +++ b/mm/frame_vector.c
> @@ -0,0 +1,232 @@
> +#include <linux/kernel.h>
> +#include <linux/errno.h>
> +#include <linux/err.h>
> +#include <linux/mm.h>
> +#include <linux/slab.h>
> +#include <linux/pagemap.h>
> +#include <linux/sched.h>
> +
> +/*
> + * get_vaddr_frames() - map virtual addresses to pfns
> + * @start: starting user address
> + * @nr_frames: number of pages / pfns from start to map
> + * @write: whether pages will be written to by the caller
> + * @force: whether to force write access even if user mapping is
> + * readonly. See description of the same argument of
> + get_user_pages().
> + * @vec: structure which receives pages / pfns of the addresses mapped.
> + * It should have space for at least nr_frames entries.
> + *
> + * This function maps virtual addresses from @start and fills @vec structure
> + * with page frame numbers or page pointers to corresponding pages (choice
> + * depends on the type of the vma underlying the virtual address). If @start
> + * belongs to a normal vma, the function grabs reference to each of the pages
> + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> + * touch page structures and the caller must make sure pfns aren't reused for
> + * anything else while he is using them.
> + *
> + * The function returns number of pages mapped which may be less than
> + * @nr_frames. In particular we stop mapping if there are more vmas of
> + * different type underlying the specified range of virtual addresses.
> + * When the function isn't able to map a single page, it returns error.
> + *
> + * This function takes care of grabbing mmap_sem as necessary.
> + */
> +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> + bool write, bool force, struct frame_vector *vec)
> +{
> + struct mm_struct *mm = current->mm;
> + struct vm_area_struct *vma;
> + int ret = 0;
> + int err;
> + int locked;
> +
> + if (nr_frames == 0)
> + return 0;
> +
> + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> + nr_frames = vec->nr_allocated;
> +
> + down_read(&mm->mmap_sem);
> + locked = 1;
> + vma = find_vma_intersection(mm, start, start + 1);
> + if (!vma) {
> + ret = -EFAULT;
> + goto out;
> + }
> + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> + vec->got_ref = true;
> + vec->is_pfns = false;
> + ret = get_user_pages_locked(current, mm, start, nr_frames,
> + write, force, (struct page **)(vec->ptrs), &locked);
> + goto out;
> + }
> +
> + vec->got_ref = false;
> + vec->is_pfns = true;
> + do {
> + unsigned long *nums = frame_vector_pfns(vec);
> +
> + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> + err = follow_pfn(vma, start, &nums[ret]);
> + if (err) {
> + if (ret == 0)
> + ret = err;
> + goto out;
> + }
> + start += PAGE_SIZE;
> + ret++;
> + }
> + /*
> + * We stop if we have enough pages or if VMA doesn't completely
> + * cover the tail page.
> + */
> + if (ret >= nr_frames || start < vma->vm_end)
> + break;
> + vma = find_vma_intersection(mm, start, start + 1);
> + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> +out:
> + if (locked)
> + up_read(&mm->mmap_sem);
> + if (!ret)
> + ret = -EFAULT;
> + if (ret > 0)
> + vec->nr_frames = ret;
> + return ret;
> +}
> +EXPORT_SYMBOL(get_vaddr_frames);
> +
> +/**
> + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> + * them
> + * @vec: frame vector to put
> + *
> + * Drop references to pages if get_vaddr_frames() acquired them. We also
> + * invalidate the frame vector so that it is prepared for the next call into
> + * get_vaddr_frames().
> + */
> +void put_vaddr_frames(struct frame_vector *vec)
> +{
> + int i;
> + struct page **pages;
> +
> + if (!vec->got_ref)
> + goto out;
> + pages = frame_vector_pages(vec);
> + /*
> + * frame_vector_pages() might needed to do a conversion when
> + * get_vaddr_frames() got pages but vec was later converted to pfns.
> + * But it shouldn't really fail to convert pfns back...
> + */
> + if (WARN_ON(IS_ERR(pages)))
> + goto out;
> + for (i = 0; i < vec->nr_frames; i++)
> + put_page(pages[i]);
> + vec->got_ref = false;
> +out:
> + vec->nr_frames = 0;
> +}
> +EXPORT_SYMBOL(put_vaddr_frames);
> +
> +/**
> + * frame_vector_to_pages - convert frame vector to contain page pointers
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of page pointers. If the conversion is
> + * successful, return 0. Otherwise return an error. Note that we do not grab
> + * page references for the page structures.
> + */
> +int frame_vector_to_pages(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (!vec->is_pfns)
> + return 0;
> + nums = frame_vector_pfns(vec);
> + for (i = 0; i < vec->nr_frames; i++)
> + if (!pfn_valid(nums[i]))
> + return -EINVAL;
> + pages = (struct page **)nums;
> + for (i = 0; i < vec->nr_frames; i++)
> + pages[i] = pfn_to_page(nums[i]);
> + vec->is_pfns = false;
> + return 0;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pages);
> +
> +/**
> + * frame_vector_to_pfns - convert frame vector to contain pfns
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of pfns.
> + */
> +void frame_vector_to_pfns(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (vec->is_pfns)
> + return;
> + pages = (struct page **)(vec->ptrs);
> + nums = (unsigned long *)pages;
> + for (i = 0; i < vec->nr_frames; i++)
> + nums[i] = page_to_pfn(pages[i]);
> + vec->is_pfns = true;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pfns);
> +
> +/**
> + * frame_vector_create() - allocate & initialize structure for pinned pfns
> + * @nr_frames: number of pfns slots we should reserve
> + *
> + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> + * pfns.
> + */
> +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> +{
> + struct frame_vector *vec;
> + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> +
> + if (WARN_ON_ONCE(nr_frames == 0))
> + return NULL;
> + /*
> + * This is absurdly high. It's here just to avoid strange effects when
> + * arithmetics overflows.
> + */
> + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> + return NULL;
> + /*
> + * Avoid higher order allocations, use vmalloc instead. It should
> + * be rare anyway.
> + */
> + if (size <= PAGE_SIZE)
> + vec = kmalloc(size, GFP_KERNEL);
> + else
> + vec = vmalloc(size);
> + if (!vec)
> + return NULL;
> + vec->nr_allocated = nr_frames;
> + vec->nr_frames = 0;
> + return vec;
> +}
> +EXPORT_SYMBOL(frame_vector_create);
> +
> +/**
> + * frame_vector_destroy() - free memory allocated to carry frame vector
> + * @vec: Frame vector to free
> + *
> + * Free structure allocated by frame_vector_create() to carry frames.
> + */
> +void frame_vector_destroy(struct frame_vector *vec)
> +{
> + /* Make sure put_vaddr_frames() got called properly... */
> + VM_BUG_ON(vec->nr_frames > 0);
> + if (!is_vmalloc_addr(vec))
> + kfree(vec);
> + else
> + vfree(vec);
> +}
> +EXPORT_SYMBOL(frame_vector_destroy);
> diff --git a/mm/gup.c b/mm/gup.c
> index 9d7f4fde30cb..222d57e335f9 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> return ret; /* 0 or negative error code */
> }
>
> -/*
> - * get_vaddr_frames() - map virtual addresses to pfns
> - * @start: starting user address
> - * @nr_frames: number of pages / pfns from start to map
> - * @write: whether pages will be written to by the caller
> - * @force: whether to force write access even if user mapping is
> - * readonly. See description of the same argument of
> - get_user_pages().
> - * @vec: structure which receives pages / pfns of the addresses mapped.
> - * It should have space for at least nr_frames entries.
> - *
> - * This function maps virtual addresses from @start and fills @vec structure
> - * with page frame numbers or page pointers to corresponding pages (choice
> - * depends on the type of the vma underlying the virtual address). If @start
> - * belongs to a normal vma, the function grabs reference to each of the pages
> - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> - * touch page structures and the caller must make sure pfns aren't reused for
> - * anything else while he is using them.
> - *
> - * The function returns number of pages mapped which may be less than
> - * @nr_frames. In particular we stop mapping if there are more vmas of
> - * different type underlying the specified range of virtual addresses.
> - * When the function isn't able to map a single page, it returns error.
> - *
> - * This function takes care of grabbing mmap_sem as necessary.
> - */
> -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> - bool write, bool force, struct frame_vector *vec)
> -{
> - struct mm_struct *mm = current->mm;
> - struct vm_area_struct *vma;
> - int ret = 0;
> - int err;
> - int locked;
> -
> - if (nr_frames == 0)
> - return 0;
> -
> - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> - nr_frames = vec->nr_allocated;
> -
> - down_read(&mm->mmap_sem);
> - locked = 1;
> - vma = find_vma_intersection(mm, start, start + 1);
> - if (!vma) {
> - ret = -EFAULT;
> - goto out;
> - }
> - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> - vec->got_ref = true;
> - vec->is_pfns = false;
> - ret = get_user_pages_locked(current, mm, start, nr_frames,
> - write, force, (struct page **)(vec->ptrs), &locked);
> - goto out;
> - }
> -
> - vec->got_ref = false;
> - vec->is_pfns = true;
> - do {
> - unsigned long *nums = frame_vector_pfns(vec);
> -
> - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> - err = follow_pfn(vma, start, &nums[ret]);
> - if (err) {
> - if (ret == 0)
> - ret = err;
> - goto out;
> - }
> - start += PAGE_SIZE;
> - ret++;
> - }
> - /*
> - * We stop if we have enough pages or if VMA doesn't completely
> - * cover the tail page.
> - */
> - if (ret >= nr_frames || start < vma->vm_end)
> - break;
> - vma = find_vma_intersection(mm, start, start + 1);
> - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> -out:
> - if (locked)
> - up_read(&mm->mmap_sem);
> - if (!ret)
> - ret = -EFAULT;
> - if (ret > 0)
> - vec->nr_frames = ret;
> - return ret;
> -}
> -EXPORT_SYMBOL(get_vaddr_frames);
> -
> -/**
> - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> - * them
> - * @vec: frame vector to put
> - *
> - * Drop references to pages if get_vaddr_frames() acquired them. We also
> - * invalidate the frame vector so that it is prepared for the next call into
> - * get_vaddr_frames().
> - */
> -void put_vaddr_frames(struct frame_vector *vec)
> -{
> - int i;
> - struct page **pages;
> -
> - if (!vec->got_ref)
> - goto out;
> - pages = frame_vector_pages(vec);
> - /*
> - * frame_vector_pages() might needed to do a conversion when
> - * get_vaddr_frames() got pages but vec was later converted to pfns.
> - * But it shouldn't really fail to convert pfns back...
> - */
> - if (WARN_ON(IS_ERR(pages)))
> - goto out;
> - for (i = 0; i < vec->nr_frames; i++)
> - put_page(pages[i]);
> - vec->got_ref = false;
> -out:
> - vec->nr_frames = 0;
> -}
> -EXPORT_SYMBOL(put_vaddr_frames);
> -
> -/**
> - * frame_vector_to_pages - convert frame vector to contain page pointers
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of page pointers. If the conversion is
> - * successful, return 0. Otherwise return an error. Note that we do not grab
> - * page references for the page structures.
> - */
> -int frame_vector_to_pages(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (!vec->is_pfns)
> - return 0;
> - nums = frame_vector_pfns(vec);
> - for (i = 0; i < vec->nr_frames; i++)
> - if (!pfn_valid(nums[i]))
> - return -EINVAL;
> - pages = (struct page **)nums;
> - for (i = 0; i < vec->nr_frames; i++)
> - pages[i] = pfn_to_page(nums[i]);
> - vec->is_pfns = false;
> - return 0;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pages);
> -
> -/**
> - * frame_vector_to_pfns - convert frame vector to contain pfns
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of pfns.
> - */
> -void frame_vector_to_pfns(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (vec->is_pfns)
> - return;
> - pages = (struct page **)(vec->ptrs);
> - nums = (unsigned long *)pages;
> - for (i = 0; i < vec->nr_frames; i++)
> - nums[i] = page_to_pfn(pages[i]);
> - vec->is_pfns = true;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pfns);
> -
> -/**
> - * frame_vector_create() - allocate & initialize structure for pinned pfns
> - * @nr_frames: number of pfns slots we should reserve
> - *
> - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> - * pfns.
> - */
> -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> -{
> - struct frame_vector *vec;
> - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> -
> - if (WARN_ON_ONCE(nr_frames == 0))
> - return NULL;
> - /*
> - * This is absurdly high. It's here just to avoid strange effects when
> - * arithmetics overflows.
> - */
> - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> - return NULL;
> - /*
> - * Avoid higher order allocations, use vmalloc instead. It should
> - * be rare anyway.
> - */
> - if (size <= PAGE_SIZE)
> - vec = kmalloc(size, GFP_KERNEL);
> - else
> - vec = vmalloc(size);
> - if (!vec)
> - return NULL;
> - vec->nr_allocated = nr_frames;
> - vec->nr_frames = 0;
> - return vec;
> -}
> -EXPORT_SYMBOL(frame_vector_create);
> -
> -/**
> - * frame_vector_destroy() - free memory allocated to carry frame vector
> - * @vec: Frame vector to free
> - *
> - * Free structure allocated by frame_vector_create() to carry frames.
> - */
> -void frame_vector_destroy(struct frame_vector *vec)
> -{
> - /* Make sure put_vaddr_frames() got called properly... */
> - VM_BUG_ON(vec->nr_frames > 0);
> - if (!is_vmalloc_addr(vec))
> - kfree(vec);
> - else
> - vfree(vec);
> -}
> -EXPORT_SYMBOL(frame_vector_destroy);
> -
> /**
> * get_dump_page() - pin user page in memory while writing it to core dump
> * @addr: user address
> --
> 2.4.2
>
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-10 16:37 ` Josh Triplett
0 siblings, 0 replies; 35+ messages in thread
From: Josh Triplett @ 2015-06-10 16:37 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Inki Dae, Joonyoung Shim, Seung-Woo Kim,
Kyungmin Park, David Airlie, Kukjin Kim, Hans Verkuil,
Paul Bolle, Randy Dunlap, Jiri Kosina, Geert Uytterhoeven,
Mark Brown, Dan Streetman, Joonsoo Kim, Minchan Kim,
Paul E. McKenney, Steve Capper, Sasha Levin, Ganesh Mahendran,
Christoph Jaeger, Michal Hocko, Johannes Weiner, Andrey Ryabinin,
Konstantin Khlebnikov, Matthew Wilcox, Al Viro,
Kirill A. Shutemov, Christian Borntraeger, Andrea Arcangeli,
Paul Cassella, Aneesh Kumar K.V, Naoya Horiguchi, dri-devel,
linux-arm-kernel, linux-samsung-soc, linux-mm
On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> From: Jan Kara <jack@suse.cz>
>
> get_vaddr_frames() is used by relatively rare drivers so hide it and the
> related functions behind a config option that is selected only by
> drivers that need the infrastructure.
>
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
>
> Signed-off-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Seems sensible to me.
Since this patch makes the kernel smaller, can you include the delta
from bloat-o-meter between allnoconfig with and without this patch?
Also, I assume you've compile-tested the kernel with allyesconfig minus
the three options that now have "select FRAME_VECTOR", to make sure it
builds?
> create mode 100644 mm/frame_vector.c
>
> diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> index 0a6780367d28..fc678289cf79 100644
> --- a/drivers/gpu/drm/exynos/Kconfig
> +++ b/drivers/gpu/drm/exynos/Kconfig
> @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> config DRM_EXYNOS_G2D
> bool "Exynos DRM G2D"
> depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> + select FRAME_VECTOR
> help
> Choose this option if you want to use Exynos G2D for DRM.
>
> diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> index dc2aaab54aef..217d613b0fe7 100644
> --- a/drivers/media/platform/omap/Kconfig
> +++ b/drivers/media/platform/omap/Kconfig
> @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> + select FRAME_VECTOR
> default n
> ---help---
> V4L2 Display driver support for OMAP2/3 based boards.
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index f7a01a72eb9e..f38f6e387f04 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
>
> config VIDEOBUF2_MEMOPS
> tristate
> + select FRAME_VECTOR
>
> config VIDEOBUF2_DMA_CONTIG
> tristate
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 390214da4546..2ca52e9986f0 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> changed to a smaller value in which case that is used.
>
> A sane initial value is 80 MB.
> +
> +config FRAME_VECTOR
> + bool
> diff --git a/mm/Makefile b/mm/Makefile
> index 98c4eaeabdcb..be5d5c866305 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> new file mode 100644
> index 000000000000..31a2bd5f41d5
> --- /dev/null
> +++ b/mm/frame_vector.c
> @@ -0,0 +1,232 @@
> +#include <linux/kernel.h>
> +#include <linux/errno.h>
> +#include <linux/err.h>
> +#include <linux/mm.h>
> +#include <linux/slab.h>
> +#include <linux/pagemap.h>
> +#include <linux/sched.h>
> +
> +/*
> + * get_vaddr_frames() - map virtual addresses to pfns
> + * @start: starting user address
> + * @nr_frames: number of pages / pfns from start to map
> + * @write: whether pages will be written to by the caller
> + * @force: whether to force write access even if user mapping is
> + * readonly. See description of the same argument of
> + get_user_pages().
> + * @vec: structure which receives pages / pfns of the addresses mapped.
> + * It should have space for at least nr_frames entries.
> + *
> + * This function maps virtual addresses from @start and fills @vec structure
> + * with page frame numbers or page pointers to corresponding pages (choice
> + * depends on the type of the vma underlying the virtual address). If @start
> + * belongs to a normal vma, the function grabs reference to each of the pages
> + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> + * touch page structures and the caller must make sure pfns aren't reused for
> + * anything else while he is using them.
> + *
> + * The function returns number of pages mapped which may be less than
> + * @nr_frames. In particular we stop mapping if there are more vmas of
> + * different type underlying the specified range of virtual addresses.
> + * When the function isn't able to map a single page, it returns error.
> + *
> + * This function takes care of grabbing mmap_sem as necessary.
> + */
> +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> + bool write, bool force, struct frame_vector *vec)
> +{
> + struct mm_struct *mm = current->mm;
> + struct vm_area_struct *vma;
> + int ret = 0;
> + int err;
> + int locked;
> +
> + if (nr_frames == 0)
> + return 0;
> +
> + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> + nr_frames = vec->nr_allocated;
> +
> + down_read(&mm->mmap_sem);
> + locked = 1;
> + vma = find_vma_intersection(mm, start, start + 1);
> + if (!vma) {
> + ret = -EFAULT;
> + goto out;
> + }
> + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> + vec->got_ref = true;
> + vec->is_pfns = false;
> + ret = get_user_pages_locked(current, mm, start, nr_frames,
> + write, force, (struct page **)(vec->ptrs), &locked);
> + goto out;
> + }
> +
> + vec->got_ref = false;
> + vec->is_pfns = true;
> + do {
> + unsigned long *nums = frame_vector_pfns(vec);
> +
> + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> + err = follow_pfn(vma, start, &nums[ret]);
> + if (err) {
> + if (ret == 0)
> + ret = err;
> + goto out;
> + }
> + start += PAGE_SIZE;
> + ret++;
> + }
> + /*
> + * We stop if we have enough pages or if VMA doesn't completely
> + * cover the tail page.
> + */
> + if (ret >= nr_frames || start < vma->vm_end)
> + break;
> + vma = find_vma_intersection(mm, start, start + 1);
> + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> +out:
> + if (locked)
> + up_read(&mm->mmap_sem);
> + if (!ret)
> + ret = -EFAULT;
> + if (ret > 0)
> + vec->nr_frames = ret;
> + return ret;
> +}
> +EXPORT_SYMBOL(get_vaddr_frames);
> +
> +/**
> + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> + * them
> + * @vec: frame vector to put
> + *
> + * Drop references to pages if get_vaddr_frames() acquired them. We also
> + * invalidate the frame vector so that it is prepared for the next call into
> + * get_vaddr_frames().
> + */
> +void put_vaddr_frames(struct frame_vector *vec)
> +{
> + int i;
> + struct page **pages;
> +
> + if (!vec->got_ref)
> + goto out;
> + pages = frame_vector_pages(vec);
> + /*
> + * frame_vector_pages() might needed to do a conversion when
> + * get_vaddr_frames() got pages but vec was later converted to pfns.
> + * But it shouldn't really fail to convert pfns back...
> + */
> + if (WARN_ON(IS_ERR(pages)))
> + goto out;
> + for (i = 0; i < vec->nr_frames; i++)
> + put_page(pages[i]);
> + vec->got_ref = false;
> +out:
> + vec->nr_frames = 0;
> +}
> +EXPORT_SYMBOL(put_vaddr_frames);
> +
> +/**
> + * frame_vector_to_pages - convert frame vector to contain page pointers
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of page pointers. If the conversion is
> + * successful, return 0. Otherwise return an error. Note that we do not grab
> + * page references for the page structures.
> + */
> +int frame_vector_to_pages(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (!vec->is_pfns)
> + return 0;
> + nums = frame_vector_pfns(vec);
> + for (i = 0; i < vec->nr_frames; i++)
> + if (!pfn_valid(nums[i]))
> + return -EINVAL;
> + pages = (struct page **)nums;
> + for (i = 0; i < vec->nr_frames; i++)
> + pages[i] = pfn_to_page(nums[i]);
> + vec->is_pfns = false;
> + return 0;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pages);
> +
> +/**
> + * frame_vector_to_pfns - convert frame vector to contain pfns
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of pfns.
> + */
> +void frame_vector_to_pfns(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (vec->is_pfns)
> + return;
> + pages = (struct page **)(vec->ptrs);
> + nums = (unsigned long *)pages;
> + for (i = 0; i < vec->nr_frames; i++)
> + nums[i] = page_to_pfn(pages[i]);
> + vec->is_pfns = true;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pfns);
> +
> +/**
> + * frame_vector_create() - allocate & initialize structure for pinned pfns
> + * @nr_frames: number of pfns slots we should reserve
> + *
> + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> + * pfns.
> + */
> +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> +{
> + struct frame_vector *vec;
> + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> +
> + if (WARN_ON_ONCE(nr_frames == 0))
> + return NULL;
> + /*
> + * This is absurdly high. It's here just to avoid strange effects when
> + * arithmetics overflows.
> + */
> + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> + return NULL;
> + /*
> + * Avoid higher order allocations, use vmalloc instead. It should
> + * be rare anyway.
> + */
> + if (size <= PAGE_SIZE)
> + vec = kmalloc(size, GFP_KERNEL);
> + else
> + vec = vmalloc(size);
> + if (!vec)
> + return NULL;
> + vec->nr_allocated = nr_frames;
> + vec->nr_frames = 0;
> + return vec;
> +}
> +EXPORT_SYMBOL(frame_vector_create);
> +
> +/**
> + * frame_vector_destroy() - free memory allocated to carry frame vector
> + * @vec: Frame vector to free
> + *
> + * Free structure allocated by frame_vector_create() to carry frames.
> + */
> +void frame_vector_destroy(struct frame_vector *vec)
> +{
> + /* Make sure put_vaddr_frames() got called properly... */
> + VM_BUG_ON(vec->nr_frames > 0);
> + if (!is_vmalloc_addr(vec))
> + kfree(vec);
> + else
> + vfree(vec);
> +}
> +EXPORT_SYMBOL(frame_vector_destroy);
> diff --git a/mm/gup.c b/mm/gup.c
> index 9d7f4fde30cb..222d57e335f9 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> return ret; /* 0 or negative error code */
> }
>
> -/*
> - * get_vaddr_frames() - map virtual addresses to pfns
> - * @start: starting user address
> - * @nr_frames: number of pages / pfns from start to map
> - * @write: whether pages will be written to by the caller
> - * @force: whether to force write access even if user mapping is
> - * readonly. See description of the same argument of
> - get_user_pages().
> - * @vec: structure which receives pages / pfns of the addresses mapped.
> - * It should have space for at least nr_frames entries.
> - *
> - * This function maps virtual addresses from @start and fills @vec structure
> - * with page frame numbers or page pointers to corresponding pages (choice
> - * depends on the type of the vma underlying the virtual address). If @start
> - * belongs to a normal vma, the function grabs reference to each of the pages
> - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> - * touch page structures and the caller must make sure pfns aren't reused for
> - * anything else while he is using them.
> - *
> - * The function returns number of pages mapped which may be less than
> - * @nr_frames. In particular we stop mapping if there are more vmas of
> - * different type underlying the specified range of virtual addresses.
> - * When the function isn't able to map a single page, it returns error.
> - *
> - * This function takes care of grabbing mmap_sem as necessary.
> - */
> -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> - bool write, bool force, struct frame_vector *vec)
> -{
> - struct mm_struct *mm = current->mm;
> - struct vm_area_struct *vma;
> - int ret = 0;
> - int err;
> - int locked;
> -
> - if (nr_frames == 0)
> - return 0;
> -
> - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> - nr_frames = vec->nr_allocated;
> -
> - down_read(&mm->mmap_sem);
> - locked = 1;
> - vma = find_vma_intersection(mm, start, start + 1);
> - if (!vma) {
> - ret = -EFAULT;
> - goto out;
> - }
> - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> - vec->got_ref = true;
> - vec->is_pfns = false;
> - ret = get_user_pages_locked(current, mm, start, nr_frames,
> - write, force, (struct page **)(vec->ptrs), &locked);
> - goto out;
> - }
> -
> - vec->got_ref = false;
> - vec->is_pfns = true;
> - do {
> - unsigned long *nums = frame_vector_pfns(vec);
> -
> - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> - err = follow_pfn(vma, start, &nums[ret]);
> - if (err) {
> - if (ret == 0)
> - ret = err;
> - goto out;
> - }
> - start += PAGE_SIZE;
> - ret++;
> - }
> - /*
> - * We stop if we have enough pages or if VMA doesn't completely
> - * cover the tail page.
> - */
> - if (ret >= nr_frames || start < vma->vm_end)
> - break;
> - vma = find_vma_intersection(mm, start, start + 1);
> - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> -out:
> - if (locked)
> - up_read(&mm->mmap_sem);
> - if (!ret)
> - ret = -EFAULT;
> - if (ret > 0)
> - vec->nr_frames = ret;
> - return ret;
> -}
> -EXPORT_SYMBOL(get_vaddr_frames);
> -
> -/**
> - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> - * them
> - * @vec: frame vector to put
> - *
> - * Drop references to pages if get_vaddr_frames() acquired them. We also
> - * invalidate the frame vector so that it is prepared for the next call into
> - * get_vaddr_frames().
> - */
> -void put_vaddr_frames(struct frame_vector *vec)
> -{
> - int i;
> - struct page **pages;
> -
> - if (!vec->got_ref)
> - goto out;
> - pages = frame_vector_pages(vec);
> - /*
> - * frame_vector_pages() might needed to do a conversion when
> - * get_vaddr_frames() got pages but vec was later converted to pfns.
> - * But it shouldn't really fail to convert pfns back...
> - */
> - if (WARN_ON(IS_ERR(pages)))
> - goto out;
> - for (i = 0; i < vec->nr_frames; i++)
> - put_page(pages[i]);
> - vec->got_ref = false;
> -out:
> - vec->nr_frames = 0;
> -}
> -EXPORT_SYMBOL(put_vaddr_frames);
> -
> -/**
> - * frame_vector_to_pages - convert frame vector to contain page pointers
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of page pointers. If the conversion is
> - * successful, return 0. Otherwise return an error. Note that we do not grab
> - * page references for the page structures.
> - */
> -int frame_vector_to_pages(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (!vec->is_pfns)
> - return 0;
> - nums = frame_vector_pfns(vec);
> - for (i = 0; i < vec->nr_frames; i++)
> - if (!pfn_valid(nums[i]))
> - return -EINVAL;
> - pages = (struct page **)nums;
> - for (i = 0; i < vec->nr_frames; i++)
> - pages[i] = pfn_to_page(nums[i]);
> - vec->is_pfns = false;
> - return 0;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pages);
> -
> -/**
> - * frame_vector_to_pfns - convert frame vector to contain pfns
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of pfns.
> - */
> -void frame_vector_to_pfns(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (vec->is_pfns)
> - return;
> - pages = (struct page **)(vec->ptrs);
> - nums = (unsigned long *)pages;
> - for (i = 0; i < vec->nr_frames; i++)
> - nums[i] = page_to_pfn(pages[i]);
> - vec->is_pfns = true;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pfns);
> -
> -/**
> - * frame_vector_create() - allocate & initialize structure for pinned pfns
> - * @nr_frames: number of pfns slots we should reserve
> - *
> - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> - * pfns.
> - */
> -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> -{
> - struct frame_vector *vec;
> - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> -
> - if (WARN_ON_ONCE(nr_frames == 0))
> - return NULL;
> - /*
> - * This is absurdly high. It's here just to avoid strange effects when
> - * arithmetics overflows.
> - */
> - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> - return NULL;
> - /*
> - * Avoid higher order allocations, use vmalloc instead. It should
> - * be rare anyway.
> - */
> - if (size <= PAGE_SIZE)
> - vec = kmalloc(size, GFP_KERNEL);
> - else
> - vec = vmalloc(size);
> - if (!vec)
> - return NULL;
> - vec->nr_allocated = nr_frames;
> - vec->nr_frames = 0;
> - return vec;
> -}
> -EXPORT_SYMBOL(frame_vector_create);
> -
> -/**
> - * frame_vector_destroy() - free memory allocated to carry frame vector
> - * @vec: Frame vector to free
> - *
> - * Free structure allocated by frame_vector_create() to carry frames.
> - */
> -void frame_vector_destroy(struct frame_vector *vec)
> -{
> - /* Make sure put_vaddr_frames() got called properly... */
> - VM_BUG_ON(vec->nr_frames > 0);
> - if (!is_vmalloc_addr(vec))
> - kfree(vec);
> - else
> - vfree(vec);
> -}
> -EXPORT_SYMBOL(frame_vector_destroy);
> -
> /**
> * get_dump_page() - pin user page in memory while writing it to core dump
> * @addr: user address
> --
> 2.4.2
>
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^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-10 16:37 ` Josh Triplett
0 siblings, 0 replies; 35+ messages in thread
From: Josh Triplett @ 2015-06-10 16:37 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Andrew Morton, Jan Kara, Linux Media Mailing List,
Mauro Carvalho Chehab, Inki Dae, Joonyoung Shim, Seung-Woo Kim,
Kyungmin Park, David Airlie, Kukjin Kim, Hans Verkuil,
Paul Bolle, Randy Dunlap, Jiri Kosina, Geert Uytterhoeven,
Mark Brown, Dan Streetman, Joonsoo Kim, Minchan Kim,
Paul E. McKenney, Steve Capper, Sasha Levin, Ganesh Mahendran
On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> From: Jan Kara <jack@suse.cz>
>
> get_vaddr_frames() is used by relatively rare drivers so hide it and the
> related functions behind a config option that is selected only by
> drivers that need the infrastructure.
>
> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
>
> Signed-off-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Seems sensible to me.
Since this patch makes the kernel smaller, can you include the delta
from bloat-o-meter between allnoconfig with and without this patch?
Also, I assume you've compile-tested the kernel with allyesconfig minus
the three options that now have "select FRAME_VECTOR", to make sure it
builds?
> create mode 100644 mm/frame_vector.c
>
> diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> index 0a6780367d28..fc678289cf79 100644
> --- a/drivers/gpu/drm/exynos/Kconfig
> +++ b/drivers/gpu/drm/exynos/Kconfig
> @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> config DRM_EXYNOS_G2D
> bool "Exynos DRM G2D"
> depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> + select FRAME_VECTOR
> help
> Choose this option if you want to use Exynos G2D for DRM.
>
> diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> index dc2aaab54aef..217d613b0fe7 100644
> --- a/drivers/media/platform/omap/Kconfig
> +++ b/drivers/media/platform/omap/Kconfig
> @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> + select FRAME_VECTOR
> default n
> ---help---
> V4L2 Display driver support for OMAP2/3 based boards.
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index f7a01a72eb9e..f38f6e387f04 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
>
> config VIDEOBUF2_MEMOPS
> tristate
> + select FRAME_VECTOR
>
> config VIDEOBUF2_DMA_CONTIG
> tristate
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 390214da4546..2ca52e9986f0 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> changed to a smaller value in which case that is used.
>
> A sane initial value is 80 MB.
> +
> +config FRAME_VECTOR
> + bool
> diff --git a/mm/Makefile b/mm/Makefile
> index 98c4eaeabdcb..be5d5c866305 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> new file mode 100644
> index 000000000000..31a2bd5f41d5
> --- /dev/null
> +++ b/mm/frame_vector.c
> @@ -0,0 +1,232 @@
> +#include <linux/kernel.h>
> +#include <linux/errno.h>
> +#include <linux/err.h>
> +#include <linux/mm.h>
> +#include <linux/slab.h>
> +#include <linux/pagemap.h>
> +#include <linux/sched.h>
> +
> +/*
> + * get_vaddr_frames() - map virtual addresses to pfns
> + * @start: starting user address
> + * @nr_frames: number of pages / pfns from start to map
> + * @write: whether pages will be written to by the caller
> + * @force: whether to force write access even if user mapping is
> + * readonly. See description of the same argument of
> + get_user_pages().
> + * @vec: structure which receives pages / pfns of the addresses mapped.
> + * It should have space for at least nr_frames entries.
> + *
> + * This function maps virtual addresses from @start and fills @vec structure
> + * with page frame numbers or page pointers to corresponding pages (choice
> + * depends on the type of the vma underlying the virtual address). If @start
> + * belongs to a normal vma, the function grabs reference to each of the pages
> + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> + * touch page structures and the caller must make sure pfns aren't reused for
> + * anything else while he is using them.
> + *
> + * The function returns number of pages mapped which may be less than
> + * @nr_frames. In particular we stop mapping if there are more vmas of
> + * different type underlying the specified range of virtual addresses.
> + * When the function isn't able to map a single page, it returns error.
> + *
> + * This function takes care of grabbing mmap_sem as necessary.
> + */
> +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> + bool write, bool force, struct frame_vector *vec)
> +{
> + struct mm_struct *mm = current->mm;
> + struct vm_area_struct *vma;
> + int ret = 0;
> + int err;
> + int locked;
> +
> + if (nr_frames == 0)
> + return 0;
> +
> + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> + nr_frames = vec->nr_allocated;
> +
> + down_read(&mm->mmap_sem);
> + locked = 1;
> + vma = find_vma_intersection(mm, start, start + 1);
> + if (!vma) {
> + ret = -EFAULT;
> + goto out;
> + }
> + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> + vec->got_ref = true;
> + vec->is_pfns = false;
> + ret = get_user_pages_locked(current, mm, start, nr_frames,
> + write, force, (struct page **)(vec->ptrs), &locked);
> + goto out;
> + }
> +
> + vec->got_ref = false;
> + vec->is_pfns = true;
> + do {
> + unsigned long *nums = frame_vector_pfns(vec);
> +
> + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> + err = follow_pfn(vma, start, &nums[ret]);
> + if (err) {
> + if (ret == 0)
> + ret = err;
> + goto out;
> + }
> + start += PAGE_SIZE;
> + ret++;
> + }
> + /*
> + * We stop if we have enough pages or if VMA doesn't completely
> + * cover the tail page.
> + */
> + if (ret >= nr_frames || start < vma->vm_end)
> + break;
> + vma = find_vma_intersection(mm, start, start + 1);
> + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> +out:
> + if (locked)
> + up_read(&mm->mmap_sem);
> + if (!ret)
> + ret = -EFAULT;
> + if (ret > 0)
> + vec->nr_frames = ret;
> + return ret;
> +}
> +EXPORT_SYMBOL(get_vaddr_frames);
> +
> +/**
> + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> + * them
> + * @vec: frame vector to put
> + *
> + * Drop references to pages if get_vaddr_frames() acquired them. We also
> + * invalidate the frame vector so that it is prepared for the next call into
> + * get_vaddr_frames().
> + */
> +void put_vaddr_frames(struct frame_vector *vec)
> +{
> + int i;
> + struct page **pages;
> +
> + if (!vec->got_ref)
> + goto out;
> + pages = frame_vector_pages(vec);
> + /*
> + * frame_vector_pages() might needed to do a conversion when
> + * get_vaddr_frames() got pages but vec was later converted to pfns.
> + * But it shouldn't really fail to convert pfns back...
> + */
> + if (WARN_ON(IS_ERR(pages)))
> + goto out;
> + for (i = 0; i < vec->nr_frames; i++)
> + put_page(pages[i]);
> + vec->got_ref = false;
> +out:
> + vec->nr_frames = 0;
> +}
> +EXPORT_SYMBOL(put_vaddr_frames);
> +
> +/**
> + * frame_vector_to_pages - convert frame vector to contain page pointers
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of page pointers. If the conversion is
> + * successful, return 0. Otherwise return an error. Note that we do not grab
> + * page references for the page structures.
> + */
> +int frame_vector_to_pages(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (!vec->is_pfns)
> + return 0;
> + nums = frame_vector_pfns(vec);
> + for (i = 0; i < vec->nr_frames; i++)
> + if (!pfn_valid(nums[i]))
> + return -EINVAL;
> + pages = (struct page **)nums;
> + for (i = 0; i < vec->nr_frames; i++)
> + pages[i] = pfn_to_page(nums[i]);
> + vec->is_pfns = false;
> + return 0;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pages);
> +
> +/**
> + * frame_vector_to_pfns - convert frame vector to contain pfns
> + * @vec: frame vector to convert
> + *
> + * Convert @vec to contain array of pfns.
> + */
> +void frame_vector_to_pfns(struct frame_vector *vec)
> +{
> + int i;
> + unsigned long *nums;
> + struct page **pages;
> +
> + if (vec->is_pfns)
> + return;
> + pages = (struct page **)(vec->ptrs);
> + nums = (unsigned long *)pages;
> + for (i = 0; i < vec->nr_frames; i++)
> + nums[i] = page_to_pfn(pages[i]);
> + vec->is_pfns = true;
> +}
> +EXPORT_SYMBOL(frame_vector_to_pfns);
> +
> +/**
> + * frame_vector_create() - allocate & initialize structure for pinned pfns
> + * @nr_frames: number of pfns slots we should reserve
> + *
> + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> + * pfns.
> + */
> +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> +{
> + struct frame_vector *vec;
> + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> +
> + if (WARN_ON_ONCE(nr_frames == 0))
> + return NULL;
> + /*
> + * This is absurdly high. It's here just to avoid strange effects when
> + * arithmetics overflows.
> + */
> + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> + return NULL;
> + /*
> + * Avoid higher order allocations, use vmalloc instead. It should
> + * be rare anyway.
> + */
> + if (size <= PAGE_SIZE)
> + vec = kmalloc(size, GFP_KERNEL);
> + else
> + vec = vmalloc(size);
> + if (!vec)
> + return NULL;
> + vec->nr_allocated = nr_frames;
> + vec->nr_frames = 0;
> + return vec;
> +}
> +EXPORT_SYMBOL(frame_vector_create);
> +
> +/**
> + * frame_vector_destroy() - free memory allocated to carry frame vector
> + * @vec: Frame vector to free
> + *
> + * Free structure allocated by frame_vector_create() to carry frames.
> + */
> +void frame_vector_destroy(struct frame_vector *vec)
> +{
> + /* Make sure put_vaddr_frames() got called properly... */
> + VM_BUG_ON(vec->nr_frames > 0);
> + if (!is_vmalloc_addr(vec))
> + kfree(vec);
> + else
> + vfree(vec);
> +}
> +EXPORT_SYMBOL(frame_vector_destroy);
> diff --git a/mm/gup.c b/mm/gup.c
> index 9d7f4fde30cb..222d57e335f9 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> return ret; /* 0 or negative error code */
> }
>
> -/*
> - * get_vaddr_frames() - map virtual addresses to pfns
> - * @start: starting user address
> - * @nr_frames: number of pages / pfns from start to map
> - * @write: whether pages will be written to by the caller
> - * @force: whether to force write access even if user mapping is
> - * readonly. See description of the same argument of
> - get_user_pages().
> - * @vec: structure which receives pages / pfns of the addresses mapped.
> - * It should have space for at least nr_frames entries.
> - *
> - * This function maps virtual addresses from @start and fills @vec structure
> - * with page frame numbers or page pointers to corresponding pages (choice
> - * depends on the type of the vma underlying the virtual address). If @start
> - * belongs to a normal vma, the function grabs reference to each of the pages
> - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> - * touch page structures and the caller must make sure pfns aren't reused for
> - * anything else while he is using them.
> - *
> - * The function returns number of pages mapped which may be less than
> - * @nr_frames. In particular we stop mapping if there are more vmas of
> - * different type underlying the specified range of virtual addresses.
> - * When the function isn't able to map a single page, it returns error.
> - *
> - * This function takes care of grabbing mmap_sem as necessary.
> - */
> -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> - bool write, bool force, struct frame_vector *vec)
> -{
> - struct mm_struct *mm = current->mm;
> - struct vm_area_struct *vma;
> - int ret = 0;
> - int err;
> - int locked;
> -
> - if (nr_frames == 0)
> - return 0;
> -
> - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> - nr_frames = vec->nr_allocated;
> -
> - down_read(&mm->mmap_sem);
> - locked = 1;
> - vma = find_vma_intersection(mm, start, start + 1);
> - if (!vma) {
> - ret = -EFAULT;
> - goto out;
> - }
> - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> - vec->got_ref = true;
> - vec->is_pfns = false;
> - ret = get_user_pages_locked(current, mm, start, nr_frames,
> - write, force, (struct page **)(vec->ptrs), &locked);
> - goto out;
> - }
> -
> - vec->got_ref = false;
> - vec->is_pfns = true;
> - do {
> - unsigned long *nums = frame_vector_pfns(vec);
> -
> - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> - err = follow_pfn(vma, start, &nums[ret]);
> - if (err) {
> - if (ret == 0)
> - ret = err;
> - goto out;
> - }
> - start += PAGE_SIZE;
> - ret++;
> - }
> - /*
> - * We stop if we have enough pages or if VMA doesn't completely
> - * cover the tail page.
> - */
> - if (ret >= nr_frames || start < vma->vm_end)
> - break;
> - vma = find_vma_intersection(mm, start, start + 1);
> - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> -out:
> - if (locked)
> - up_read(&mm->mmap_sem);
> - if (!ret)
> - ret = -EFAULT;
> - if (ret > 0)
> - vec->nr_frames = ret;
> - return ret;
> -}
> -EXPORT_SYMBOL(get_vaddr_frames);
> -
> -/**
> - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> - * them
> - * @vec: frame vector to put
> - *
> - * Drop references to pages if get_vaddr_frames() acquired them. We also
> - * invalidate the frame vector so that it is prepared for the next call into
> - * get_vaddr_frames().
> - */
> -void put_vaddr_frames(struct frame_vector *vec)
> -{
> - int i;
> - struct page **pages;
> -
> - if (!vec->got_ref)
> - goto out;
> - pages = frame_vector_pages(vec);
> - /*
> - * frame_vector_pages() might needed to do a conversion when
> - * get_vaddr_frames() got pages but vec was later converted to pfns.
> - * But it shouldn't really fail to convert pfns back...
> - */
> - if (WARN_ON(IS_ERR(pages)))
> - goto out;
> - for (i = 0; i < vec->nr_frames; i++)
> - put_page(pages[i]);
> - vec->got_ref = false;
> -out:
> - vec->nr_frames = 0;
> -}
> -EXPORT_SYMBOL(put_vaddr_frames);
> -
> -/**
> - * frame_vector_to_pages - convert frame vector to contain page pointers
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of page pointers. If the conversion is
> - * successful, return 0. Otherwise return an error. Note that we do not grab
> - * page references for the page structures.
> - */
> -int frame_vector_to_pages(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (!vec->is_pfns)
> - return 0;
> - nums = frame_vector_pfns(vec);
> - for (i = 0; i < vec->nr_frames; i++)
> - if (!pfn_valid(nums[i]))
> - return -EINVAL;
> - pages = (struct page **)nums;
> - for (i = 0; i < vec->nr_frames; i++)
> - pages[i] = pfn_to_page(nums[i]);
> - vec->is_pfns = false;
> - return 0;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pages);
> -
> -/**
> - * frame_vector_to_pfns - convert frame vector to contain pfns
> - * @vec: frame vector to convert
> - *
> - * Convert @vec to contain array of pfns.
> - */
> -void frame_vector_to_pfns(struct frame_vector *vec)
> -{
> - int i;
> - unsigned long *nums;
> - struct page **pages;
> -
> - if (vec->is_pfns)
> - return;
> - pages = (struct page **)(vec->ptrs);
> - nums = (unsigned long *)pages;
> - for (i = 0; i < vec->nr_frames; i++)
> - nums[i] = page_to_pfn(pages[i]);
> - vec->is_pfns = true;
> -}
> -EXPORT_SYMBOL(frame_vector_to_pfns);
> -
> -/**
> - * frame_vector_create() - allocate & initialize structure for pinned pfns
> - * @nr_frames: number of pfns slots we should reserve
> - *
> - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> - * pfns.
> - */
> -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> -{
> - struct frame_vector *vec;
> - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> -
> - if (WARN_ON_ONCE(nr_frames == 0))
> - return NULL;
> - /*
> - * This is absurdly high. It's here just to avoid strange effects when
> - * arithmetics overflows.
> - */
> - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> - return NULL;
> - /*
> - * Avoid higher order allocations, use vmalloc instead. It should
> - * be rare anyway.
> - */
> - if (size <= PAGE_SIZE)
> - vec = kmalloc(size, GFP_KERNEL);
> - else
> - vec = vmalloc(size);
> - if (!vec)
> - return NULL;
> - vec->nr_allocated = nr_frames;
> - vec->nr_frames = 0;
> - return vec;
> -}
> -EXPORT_SYMBOL(frame_vector_create);
> -
> -/**
> - * frame_vector_destroy() - free memory allocated to carry frame vector
> - * @vec: Frame vector to free
> - *
> - * Free structure allocated by frame_vector_create() to carry frames.
> - */
> -void frame_vector_destroy(struct frame_vector *vec)
> -{
> - /* Make sure put_vaddr_frames() got called properly... */
> - VM_BUG_ON(vec->nr_frames > 0);
> - if (!is_vmalloc_addr(vec))
> - kfree(vec);
> - else
> - vfree(vec);
> -}
> -EXPORT_SYMBOL(frame_vector_destroy);
> -
> /**
> * get_dump_page() - pin user page in memory while writing it to core dump
> * @addr: user address
> --
> 2.4.2
>
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^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
2015-06-10 16:37 ` Josh Triplett
(?)
(?)
@ 2015-06-18 13:44 ` Jan Kara
-1 siblings, 0 replies; 35+ messages in thread
From: Jan Kara @ 2015-06-18 13:44 UTC (permalink / raw)
To: Josh Triplett
Cc: Mauro Carvalho Chehab, Andrew Morton, Jan Kara,
Linux Media Mailing List, Mauro Carvalho Chehab, Inki Dae,
Joonyoung Shim, Seung-Woo Kim, Kyungmin Park, David Airlie,
Kukjin Kim, Hans Verkuil, Paul Bolle, Randy Dunlap, Jiri Kosina,
Geert Uytterhoeven, Mark Brown, Dan Streetman, Joonsoo Kim,
Minchan Kim, Paul E. McKenney, Steve Capper, Sasha Levin,
Ganesh Mahendran, Christoph Jaeger, Michal Hocko,
Johannes Weiner, Andrey Ryabinin, Konstantin Khlebnikov,
Matthew Wilcox, Al Viro, Kirill A. Shutemov,
Christian Borntraeger, Andrea Arcangeli, Paul Cassella,
Aneesh Kumar K.V, Naoya Horiguchi, dri-devel, linux-arm-kernel,
linux-samsung-soc, linux-mm
On Wed 10-06-15 09:37:20, Josh Triplett wrote:
> On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> > From: Jan Kara <jack@suse.cz>
> >
> > get_vaddr_frames() is used by relatively rare drivers so hide it and the
> > related functions behind a config option that is selected only by
> > drivers that need the infrastructure.
> >
> > Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> >
> > Signed-off-by: Jan Kara <jack@suse.cz>
> > Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>
> Seems sensible to me.
>
> Since this patch makes the kernel smaller, can you include the delta
> from bloat-o-meter between allnoconfig with and without this patch?
The results are:
add/remove: 0/6 grow/shrink: 0/0 up/down: 0/-868 (-868)
function old new delta
frame_vector_destroy 55 - -55
frame_vector_to_pfns 56 - -56
frame_vector_create 81 - -81
put_vaddr_frames 93 - -93
frame_vector_to_pages 98 - -98
get_vaddr_frames 485 - -485
I've added it to the changelog of the patch.
> Also, I assume you've compile-tested the kernel with allyesconfig minus
> the three options that now have "select FRAME_VECTOR", to make sure it
> builds?
I did not because the config option VIDEOBUF2_MEMOPS is a virtual one
selected transitively by quite a few video drivers and I didn't bother with
tracking down all of them... But since that config option guards
compilation of the code I modified I'm pretty confident I got it right.
Honza
> > create mode 100644 mm/frame_vector.c
> >
> > diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> > index 0a6780367d28..fc678289cf79 100644
> > --- a/drivers/gpu/drm/exynos/Kconfig
> > +++ b/drivers/gpu/drm/exynos/Kconfig
> > @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> > config DRM_EXYNOS_G2D
> > bool "Exynos DRM G2D"
> > depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> > + select FRAME_VECTOR
> > help
> > Choose this option if you want to use Exynos G2D for DRM.
> >
> > diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> > index dc2aaab54aef..217d613b0fe7 100644
> > --- a/drivers/media/platform/omap/Kconfig
> > +++ b/drivers/media/platform/omap/Kconfig
> > @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> > select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> > select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> > select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> > + select FRAME_VECTOR
> > default n
> > ---help---
> > V4L2 Display driver support for OMAP2/3 based boards.
> > diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> > index f7a01a72eb9e..f38f6e387f04 100644
> > --- a/drivers/media/v4l2-core/Kconfig
> > +++ b/drivers/media/v4l2-core/Kconfig
> > @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
> >
> > config VIDEOBUF2_MEMOPS
> > tristate
> > + select FRAME_VECTOR
> >
> > config VIDEOBUF2_DMA_CONTIG
> > tristate
> > diff --git a/mm/Kconfig b/mm/Kconfig
> > index 390214da4546..2ca52e9986f0 100644
> > --- a/mm/Kconfig
> > +++ b/mm/Kconfig
> > @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> > changed to a smaller value in which case that is used.
> >
> > A sane initial value is 80 MB.
> > +
> > +config FRAME_VECTOR
> > + bool
> > diff --git a/mm/Makefile b/mm/Makefile
> > index 98c4eaeabdcb..be5d5c866305 100644
> > --- a/mm/Makefile
> > +++ b/mm/Makefile
> > @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> > obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> > obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> > obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> > +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> > diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> > new file mode 100644
> > index 000000000000..31a2bd5f41d5
> > --- /dev/null
> > +++ b/mm/frame_vector.c
> > @@ -0,0 +1,232 @@
> > +#include <linux/kernel.h>
> > +#include <linux/errno.h>
> > +#include <linux/err.h>
> > +#include <linux/mm.h>
> > +#include <linux/slab.h>
> > +#include <linux/pagemap.h>
> > +#include <linux/sched.h>
> > +
> > +/*
> > + * get_vaddr_frames() - map virtual addresses to pfns
> > + * @start: starting user address
> > + * @nr_frames: number of pages / pfns from start to map
> > + * @write: whether pages will be written to by the caller
> > + * @force: whether to force write access even if user mapping is
> > + * readonly. See description of the same argument of
> > + get_user_pages().
> > + * @vec: structure which receives pages / pfns of the addresses mapped.
> > + * It should have space for at least nr_frames entries.
> > + *
> > + * This function maps virtual addresses from @start and fills @vec structure
> > + * with page frame numbers or page pointers to corresponding pages (choice
> > + * depends on the type of the vma underlying the virtual address). If @start
> > + * belongs to a normal vma, the function grabs reference to each of the pages
> > + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > + * touch page structures and the caller must make sure pfns aren't reused for
> > + * anything else while he is using them.
> > + *
> > + * The function returns number of pages mapped which may be less than
> > + * @nr_frames. In particular we stop mapping if there are more vmas of
> > + * different type underlying the specified range of virtual addresses.
> > + * When the function isn't able to map a single page, it returns error.
> > + *
> > + * This function takes care of grabbing mmap_sem as necessary.
> > + */
> > +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > + bool write, bool force, struct frame_vector *vec)
> > +{
> > + struct mm_struct *mm = current->mm;
> > + struct vm_area_struct *vma;
> > + int ret = 0;
> > + int err;
> > + int locked;
> > +
> > + if (nr_frames == 0)
> > + return 0;
> > +
> > + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > + nr_frames = vec->nr_allocated;
> > +
> > + down_read(&mm->mmap_sem);
> > + locked = 1;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + if (!vma) {
> > + ret = -EFAULT;
> > + goto out;
> > + }
> > + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > + vec->got_ref = true;
> > + vec->is_pfns = false;
> > + ret = get_user_pages_locked(current, mm, start, nr_frames,
> > + write, force, (struct page **)(vec->ptrs), &locked);
> > + goto out;
> > + }
> > +
> > + vec->got_ref = false;
> > + vec->is_pfns = true;
> > + do {
> > + unsigned long *nums = frame_vector_pfns(vec);
> > +
> > + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > + err = follow_pfn(vma, start, &nums[ret]);
> > + if (err) {
> > + if (ret == 0)
> > + ret = err;
> > + goto out;
> > + }
> > + start += PAGE_SIZE;
> > + ret++;
> > + }
> > + /*
> > + * We stop if we have enough pages or if VMA doesn't completely
> > + * cover the tail page.
> > + */
> > + if (ret >= nr_frames || start < vma->vm_end)
> > + break;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > +out:
> > + if (locked)
> > + up_read(&mm->mmap_sem);
> > + if (!ret)
> > + ret = -EFAULT;
> > + if (ret > 0)
> > + vec->nr_frames = ret;
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(get_vaddr_frames);
> > +
> > +/**
> > + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > + * them
> > + * @vec: frame vector to put
> > + *
> > + * Drop references to pages if get_vaddr_frames() acquired them. We also
> > + * invalidate the frame vector so that it is prepared for the next call into
> > + * get_vaddr_frames().
> > + */
> > +void put_vaddr_frames(struct frame_vector *vec)
> > +{
> > + int i;
> > + struct page **pages;
> > +
> > + if (!vec->got_ref)
> > + goto out;
> > + pages = frame_vector_pages(vec);
> > + /*
> > + * frame_vector_pages() might needed to do a conversion when
> > + * get_vaddr_frames() got pages but vec was later converted to pfns.
> > + * But it shouldn't really fail to convert pfns back...
> > + */
> > + if (WARN_ON(IS_ERR(pages)))
> > + goto out;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + put_page(pages[i]);
> > + vec->got_ref = false;
> > +out:
> > + vec->nr_frames = 0;
> > +}
> > +EXPORT_SYMBOL(put_vaddr_frames);
> > +
> > +/**
> > + * frame_vector_to_pages - convert frame vector to contain page pointers
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of page pointers. If the conversion is
> > + * successful, return 0. Otherwise return an error. Note that we do not grab
> > + * page references for the page structures.
> > + */
> > +int frame_vector_to_pages(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (!vec->is_pfns)
> > + return 0;
> > + nums = frame_vector_pfns(vec);
> > + for (i = 0; i < vec->nr_frames; i++)
> > + if (!pfn_valid(nums[i]))
> > + return -EINVAL;
> > + pages = (struct page **)nums;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + pages[i] = pfn_to_page(nums[i]);
> > + vec->is_pfns = false;
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pages);
> > +
> > +/**
> > + * frame_vector_to_pfns - convert frame vector to contain pfns
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of pfns.
> > + */
> > +void frame_vector_to_pfns(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (vec->is_pfns)
> > + return;
> > + pages = (struct page **)(vec->ptrs);
> > + nums = (unsigned long *)pages;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + nums[i] = page_to_pfn(pages[i]);
> > + vec->is_pfns = true;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pfns);
> > +
> > +/**
> > + * frame_vector_create() - allocate & initialize structure for pinned pfns
> > + * @nr_frames: number of pfns slots we should reserve
> > + *
> > + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > + * pfns.
> > + */
> > +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > +{
> > + struct frame_vector *vec;
> > + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > +
> > + if (WARN_ON_ONCE(nr_frames == 0))
> > + return NULL;
> > + /*
> > + * This is absurdly high. It's here just to avoid strange effects when
> > + * arithmetics overflows.
> > + */
> > + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > + return NULL;
> > + /*
> > + * Avoid higher order allocations, use vmalloc instead. It should
> > + * be rare anyway.
> > + */
> > + if (size <= PAGE_SIZE)
> > + vec = kmalloc(size, GFP_KERNEL);
> > + else
> > + vec = vmalloc(size);
> > + if (!vec)
> > + return NULL;
> > + vec->nr_allocated = nr_frames;
> > + vec->nr_frames = 0;
> > + return vec;
> > +}
> > +EXPORT_SYMBOL(frame_vector_create);
> > +
> > +/**
> > + * frame_vector_destroy() - free memory allocated to carry frame vector
> > + * @vec: Frame vector to free
> > + *
> > + * Free structure allocated by frame_vector_create() to carry frames.
> > + */
> > +void frame_vector_destroy(struct frame_vector *vec)
> > +{
> > + /* Make sure put_vaddr_frames() got called properly... */
> > + VM_BUG_ON(vec->nr_frames > 0);
> > + if (!is_vmalloc_addr(vec))
> > + kfree(vec);
> > + else
> > + vfree(vec);
> > +}
> > +EXPORT_SYMBOL(frame_vector_destroy);
> > diff --git a/mm/gup.c b/mm/gup.c
> > index 9d7f4fde30cb..222d57e335f9 100644
> > --- a/mm/gup.c
> > +++ b/mm/gup.c
> > @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> > return ret; /* 0 or negative error code */
> > }
> >
> > -/*
> > - * get_vaddr_frames() - map virtual addresses to pfns
> > - * @start: starting user address
> > - * @nr_frames: number of pages / pfns from start to map
> > - * @write: whether pages will be written to by the caller
> > - * @force: whether to force write access even if user mapping is
> > - * readonly. See description of the same argument of
> > - get_user_pages().
> > - * @vec: structure which receives pages / pfns of the addresses mapped.
> > - * It should have space for at least nr_frames entries.
> > - *
> > - * This function maps virtual addresses from @start and fills @vec structure
> > - * with page frame numbers or page pointers to corresponding pages (choice
> > - * depends on the type of the vma underlying the virtual address). If @start
> > - * belongs to a normal vma, the function grabs reference to each of the pages
> > - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > - * touch page structures and the caller must make sure pfns aren't reused for
> > - * anything else while he is using them.
> > - *
> > - * The function returns number of pages mapped which may be less than
> > - * @nr_frames. In particular we stop mapping if there are more vmas of
> > - * different type underlying the specified range of virtual addresses.
> > - * When the function isn't able to map a single page, it returns error.
> > - *
> > - * This function takes care of grabbing mmap_sem as necessary.
> > - */
> > -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > - bool write, bool force, struct frame_vector *vec)
> > -{
> > - struct mm_struct *mm = current->mm;
> > - struct vm_area_struct *vma;
> > - int ret = 0;
> > - int err;
> > - int locked;
> > -
> > - if (nr_frames == 0)
> > - return 0;
> > -
> > - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > - nr_frames = vec->nr_allocated;
> > -
> > - down_read(&mm->mmap_sem);
> > - locked = 1;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - if (!vma) {
> > - ret = -EFAULT;
> > - goto out;
> > - }
> > - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > - vec->got_ref = true;
> > - vec->is_pfns = false;
> > - ret = get_user_pages_locked(current, mm, start, nr_frames,
> > - write, force, (struct page **)(vec->ptrs), &locked);
> > - goto out;
> > - }
> > -
> > - vec->got_ref = false;
> > - vec->is_pfns = true;
> > - do {
> > - unsigned long *nums = frame_vector_pfns(vec);
> > -
> > - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > - err = follow_pfn(vma, start, &nums[ret]);
> > - if (err) {
> > - if (ret == 0)
> > - ret = err;
> > - goto out;
> > - }
> > - start += PAGE_SIZE;
> > - ret++;
> > - }
> > - /*
> > - * We stop if we have enough pages or if VMA doesn't completely
> > - * cover the tail page.
> > - */
> > - if (ret >= nr_frames || start < vma->vm_end)
> > - break;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > -out:
> > - if (locked)
> > - up_read(&mm->mmap_sem);
> > - if (!ret)
> > - ret = -EFAULT;
> > - if (ret > 0)
> > - vec->nr_frames = ret;
> > - return ret;
> > -}
> > -EXPORT_SYMBOL(get_vaddr_frames);
> > -
> > -/**
> > - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > - * them
> > - * @vec: frame vector to put
> > - *
> > - * Drop references to pages if get_vaddr_frames() acquired them. We also
> > - * invalidate the frame vector so that it is prepared for the next call into
> > - * get_vaddr_frames().
> > - */
> > -void put_vaddr_frames(struct frame_vector *vec)
> > -{
> > - int i;
> > - struct page **pages;
> > -
> > - if (!vec->got_ref)
> > - goto out;
> > - pages = frame_vector_pages(vec);
> > - /*
> > - * frame_vector_pages() might needed to do a conversion when
> > - * get_vaddr_frames() got pages but vec was later converted to pfns.
> > - * But it shouldn't really fail to convert pfns back...
> > - */
> > - if (WARN_ON(IS_ERR(pages)))
> > - goto out;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - put_page(pages[i]);
> > - vec->got_ref = false;
> > -out:
> > - vec->nr_frames = 0;
> > -}
> > -EXPORT_SYMBOL(put_vaddr_frames);
> > -
> > -/**
> > - * frame_vector_to_pages - convert frame vector to contain page pointers
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of page pointers. If the conversion is
> > - * successful, return 0. Otherwise return an error. Note that we do not grab
> > - * page references for the page structures.
> > - */
> > -int frame_vector_to_pages(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (!vec->is_pfns)
> > - return 0;
> > - nums = frame_vector_pfns(vec);
> > - for (i = 0; i < vec->nr_frames; i++)
> > - if (!pfn_valid(nums[i]))
> > - return -EINVAL;
> > - pages = (struct page **)nums;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - pages[i] = pfn_to_page(nums[i]);
> > - vec->is_pfns = false;
> > - return 0;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pages);
> > -
> > -/**
> > - * frame_vector_to_pfns - convert frame vector to contain pfns
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of pfns.
> > - */
> > -void frame_vector_to_pfns(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (vec->is_pfns)
> > - return;
> > - pages = (struct page **)(vec->ptrs);
> > - nums = (unsigned long *)pages;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - nums[i] = page_to_pfn(pages[i]);
> > - vec->is_pfns = true;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pfns);
> > -
> > -/**
> > - * frame_vector_create() - allocate & initialize structure for pinned pfns
> > - * @nr_frames: number of pfns slots we should reserve
> > - *
> > - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > - * pfns.
> > - */
> > -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > -{
> > - struct frame_vector *vec;
> > - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > -
> > - if (WARN_ON_ONCE(nr_frames == 0))
> > - return NULL;
> > - /*
> > - * This is absurdly high. It's here just to avoid strange effects when
> > - * arithmetics overflows.
> > - */
> > - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > - return NULL;
> > - /*
> > - * Avoid higher order allocations, use vmalloc instead. It should
> > - * be rare anyway.
> > - */
> > - if (size <= PAGE_SIZE)
> > - vec = kmalloc(size, GFP_KERNEL);
> > - else
> > - vec = vmalloc(size);
> > - if (!vec)
> > - return NULL;
> > - vec->nr_allocated = nr_frames;
> > - vec->nr_frames = 0;
> > - return vec;
> > -}
> > -EXPORT_SYMBOL(frame_vector_create);
> > -
> > -/**
> > - * frame_vector_destroy() - free memory allocated to carry frame vector
> > - * @vec: Frame vector to free
> > - *
> > - * Free structure allocated by frame_vector_create() to carry frames.
> > - */
> > -void frame_vector_destroy(struct frame_vector *vec)
> > -{
> > - /* Make sure put_vaddr_frames() got called properly... */
> > - VM_BUG_ON(vec->nr_frames > 0);
> > - if (!is_vmalloc_addr(vec))
> > - kfree(vec);
> > - else
> > - vfree(vec);
> > -}
> > -EXPORT_SYMBOL(frame_vector_destroy);
> > -
> > /**
> > * get_dump_page() - pin user page in memory while writing it to core dump
> > * @addr: user address
> > --
> > 2.4.2
> >
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR
^ permalink raw reply [flat|nested] 35+ messages in thread* [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-18 13:44 ` Jan Kara
0 siblings, 0 replies; 35+ messages in thread
From: Jan Kara @ 2015-06-18 13:44 UTC (permalink / raw)
To: linux-arm-kernel
On Wed 10-06-15 09:37:20, Josh Triplett wrote:
> On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> > From: Jan Kara <jack@suse.cz>
> >
> > get_vaddr_frames() is used by relatively rare drivers so hide it and the
> > related functions behind a config option that is selected only by
> > drivers that need the infrastructure.
> >
> > Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> >
> > Signed-off-by: Jan Kara <jack@suse.cz>
> > Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>
> Seems sensible to me.
>
> Since this patch makes the kernel smaller, can you include the delta
> from bloat-o-meter between allnoconfig with and without this patch?
The results are:
add/remove: 0/6 grow/shrink: 0/0 up/down: 0/-868 (-868)
function old new delta
frame_vector_destroy 55 - -55
frame_vector_to_pfns 56 - -56
frame_vector_create 81 - -81
put_vaddr_frames 93 - -93
frame_vector_to_pages 98 - -98
get_vaddr_frames 485 - -485
I've added it to the changelog of the patch.
> Also, I assume you've compile-tested the kernel with allyesconfig minus
> the three options that now have "select FRAME_VECTOR", to make sure it
> builds?
I did not because the config option VIDEOBUF2_MEMOPS is a virtual one
selected transitively by quite a few video drivers and I didn't bother with
tracking down all of them... But since that config option guards
compilation of the code I modified I'm pretty confident I got it right.
Honza
> > create mode 100644 mm/frame_vector.c
> >
> > diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> > index 0a6780367d28..fc678289cf79 100644
> > --- a/drivers/gpu/drm/exynos/Kconfig
> > +++ b/drivers/gpu/drm/exynos/Kconfig
> > @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> > config DRM_EXYNOS_G2D
> > bool "Exynos DRM G2D"
> > depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> > + select FRAME_VECTOR
> > help
> > Choose this option if you want to use Exynos G2D for DRM.
> >
> > diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> > index dc2aaab54aef..217d613b0fe7 100644
> > --- a/drivers/media/platform/omap/Kconfig
> > +++ b/drivers/media/platform/omap/Kconfig
> > @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> > select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> > select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> > select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> > + select FRAME_VECTOR
> > default n
> > ---help---
> > V4L2 Display driver support for OMAP2/3 based boards.
> > diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> > index f7a01a72eb9e..f38f6e387f04 100644
> > --- a/drivers/media/v4l2-core/Kconfig
> > +++ b/drivers/media/v4l2-core/Kconfig
> > @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
> >
> > config VIDEOBUF2_MEMOPS
> > tristate
> > + select FRAME_VECTOR
> >
> > config VIDEOBUF2_DMA_CONTIG
> > tristate
> > diff --git a/mm/Kconfig b/mm/Kconfig
> > index 390214da4546..2ca52e9986f0 100644
> > --- a/mm/Kconfig
> > +++ b/mm/Kconfig
> > @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> > changed to a smaller value in which case that is used.
> >
> > A sane initial value is 80 MB.
> > +
> > +config FRAME_VECTOR
> > + bool
> > diff --git a/mm/Makefile b/mm/Makefile
> > index 98c4eaeabdcb..be5d5c866305 100644
> > --- a/mm/Makefile
> > +++ b/mm/Makefile
> > @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> > obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> > obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> > obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> > +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> > diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> > new file mode 100644
> > index 000000000000..31a2bd5f41d5
> > --- /dev/null
> > +++ b/mm/frame_vector.c
> > @@ -0,0 +1,232 @@
> > +#include <linux/kernel.h>
> > +#include <linux/errno.h>
> > +#include <linux/err.h>
> > +#include <linux/mm.h>
> > +#include <linux/slab.h>
> > +#include <linux/pagemap.h>
> > +#include <linux/sched.h>
> > +
> > +/*
> > + * get_vaddr_frames() - map virtual addresses to pfns
> > + * @start: starting user address
> > + * @nr_frames: number of pages / pfns from start to map
> > + * @write: whether pages will be written to by the caller
> > + * @force: whether to force write access even if user mapping is
> > + * readonly. See description of the same argument of
> > + get_user_pages().
> > + * @vec: structure which receives pages / pfns of the addresses mapped.
> > + * It should have space for at least nr_frames entries.
> > + *
> > + * This function maps virtual addresses from @start and fills @vec structure
> > + * with page frame numbers or page pointers to corresponding pages (choice
> > + * depends on the type of the vma underlying the virtual address). If @start
> > + * belongs to a normal vma, the function grabs reference to each of the pages
> > + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > + * touch page structures and the caller must make sure pfns aren't reused for
> > + * anything else while he is using them.
> > + *
> > + * The function returns number of pages mapped which may be less than
> > + * @nr_frames. In particular we stop mapping if there are more vmas of
> > + * different type underlying the specified range of virtual addresses.
> > + * When the function isn't able to map a single page, it returns error.
> > + *
> > + * This function takes care of grabbing mmap_sem as necessary.
> > + */
> > +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > + bool write, bool force, struct frame_vector *vec)
> > +{
> > + struct mm_struct *mm = current->mm;
> > + struct vm_area_struct *vma;
> > + int ret = 0;
> > + int err;
> > + int locked;
> > +
> > + if (nr_frames == 0)
> > + return 0;
> > +
> > + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > + nr_frames = vec->nr_allocated;
> > +
> > + down_read(&mm->mmap_sem);
> > + locked = 1;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + if (!vma) {
> > + ret = -EFAULT;
> > + goto out;
> > + }
> > + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > + vec->got_ref = true;
> > + vec->is_pfns = false;
> > + ret = get_user_pages_locked(current, mm, start, nr_frames,
> > + write, force, (struct page **)(vec->ptrs), &locked);
> > + goto out;
> > + }
> > +
> > + vec->got_ref = false;
> > + vec->is_pfns = true;
> > + do {
> > + unsigned long *nums = frame_vector_pfns(vec);
> > +
> > + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > + err = follow_pfn(vma, start, &nums[ret]);
> > + if (err) {
> > + if (ret == 0)
> > + ret = err;
> > + goto out;
> > + }
> > + start += PAGE_SIZE;
> > + ret++;
> > + }
> > + /*
> > + * We stop if we have enough pages or if VMA doesn't completely
> > + * cover the tail page.
> > + */
> > + if (ret >= nr_frames || start < vma->vm_end)
> > + break;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > +out:
> > + if (locked)
> > + up_read(&mm->mmap_sem);
> > + if (!ret)
> > + ret = -EFAULT;
> > + if (ret > 0)
> > + vec->nr_frames = ret;
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(get_vaddr_frames);
> > +
> > +/**
> > + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > + * them
> > + * @vec: frame vector to put
> > + *
> > + * Drop references to pages if get_vaddr_frames() acquired them. We also
> > + * invalidate the frame vector so that it is prepared for the next call into
> > + * get_vaddr_frames().
> > + */
> > +void put_vaddr_frames(struct frame_vector *vec)
> > +{
> > + int i;
> > + struct page **pages;
> > +
> > + if (!vec->got_ref)
> > + goto out;
> > + pages = frame_vector_pages(vec);
> > + /*
> > + * frame_vector_pages() might needed to do a conversion when
> > + * get_vaddr_frames() got pages but vec was later converted to pfns.
> > + * But it shouldn't really fail to convert pfns back...
> > + */
> > + if (WARN_ON(IS_ERR(pages)))
> > + goto out;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + put_page(pages[i]);
> > + vec->got_ref = false;
> > +out:
> > + vec->nr_frames = 0;
> > +}
> > +EXPORT_SYMBOL(put_vaddr_frames);
> > +
> > +/**
> > + * frame_vector_to_pages - convert frame vector to contain page pointers
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of page pointers. If the conversion is
> > + * successful, return 0. Otherwise return an error. Note that we do not grab
> > + * page references for the page structures.
> > + */
> > +int frame_vector_to_pages(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (!vec->is_pfns)
> > + return 0;
> > + nums = frame_vector_pfns(vec);
> > + for (i = 0; i < vec->nr_frames; i++)
> > + if (!pfn_valid(nums[i]))
> > + return -EINVAL;
> > + pages = (struct page **)nums;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + pages[i] = pfn_to_page(nums[i]);
> > + vec->is_pfns = false;
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pages);
> > +
> > +/**
> > + * frame_vector_to_pfns - convert frame vector to contain pfns
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of pfns.
> > + */
> > +void frame_vector_to_pfns(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (vec->is_pfns)
> > + return;
> > + pages = (struct page **)(vec->ptrs);
> > + nums = (unsigned long *)pages;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + nums[i] = page_to_pfn(pages[i]);
> > + vec->is_pfns = true;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pfns);
> > +
> > +/**
> > + * frame_vector_create() - allocate & initialize structure for pinned pfns
> > + * @nr_frames: number of pfns slots we should reserve
> > + *
> > + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > + * pfns.
> > + */
> > +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > +{
> > + struct frame_vector *vec;
> > + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > +
> > + if (WARN_ON_ONCE(nr_frames == 0))
> > + return NULL;
> > + /*
> > + * This is absurdly high. It's here just to avoid strange effects when
> > + * arithmetics overflows.
> > + */
> > + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > + return NULL;
> > + /*
> > + * Avoid higher order allocations, use vmalloc instead. It should
> > + * be rare anyway.
> > + */
> > + if (size <= PAGE_SIZE)
> > + vec = kmalloc(size, GFP_KERNEL);
> > + else
> > + vec = vmalloc(size);
> > + if (!vec)
> > + return NULL;
> > + vec->nr_allocated = nr_frames;
> > + vec->nr_frames = 0;
> > + return vec;
> > +}
> > +EXPORT_SYMBOL(frame_vector_create);
> > +
> > +/**
> > + * frame_vector_destroy() - free memory allocated to carry frame vector
> > + * @vec: Frame vector to free
> > + *
> > + * Free structure allocated by frame_vector_create() to carry frames.
> > + */
> > +void frame_vector_destroy(struct frame_vector *vec)
> > +{
> > + /* Make sure put_vaddr_frames() got called properly... */
> > + VM_BUG_ON(vec->nr_frames > 0);
> > + if (!is_vmalloc_addr(vec))
> > + kfree(vec);
> > + else
> > + vfree(vec);
> > +}
> > +EXPORT_SYMBOL(frame_vector_destroy);
> > diff --git a/mm/gup.c b/mm/gup.c
> > index 9d7f4fde30cb..222d57e335f9 100644
> > --- a/mm/gup.c
> > +++ b/mm/gup.c
> > @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> > return ret; /* 0 or negative error code */
> > }
> >
> > -/*
> > - * get_vaddr_frames() - map virtual addresses to pfns
> > - * @start: starting user address
> > - * @nr_frames: number of pages / pfns from start to map
> > - * @write: whether pages will be written to by the caller
> > - * @force: whether to force write access even if user mapping is
> > - * readonly. See description of the same argument of
> > - get_user_pages().
> > - * @vec: structure which receives pages / pfns of the addresses mapped.
> > - * It should have space for at least nr_frames entries.
> > - *
> > - * This function maps virtual addresses from @start and fills @vec structure
> > - * with page frame numbers or page pointers to corresponding pages (choice
> > - * depends on the type of the vma underlying the virtual address). If @start
> > - * belongs to a normal vma, the function grabs reference to each of the pages
> > - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > - * touch page structures and the caller must make sure pfns aren't reused for
> > - * anything else while he is using them.
> > - *
> > - * The function returns number of pages mapped which may be less than
> > - * @nr_frames. In particular we stop mapping if there are more vmas of
> > - * different type underlying the specified range of virtual addresses.
> > - * When the function isn't able to map a single page, it returns error.
> > - *
> > - * This function takes care of grabbing mmap_sem as necessary.
> > - */
> > -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > - bool write, bool force, struct frame_vector *vec)
> > -{
> > - struct mm_struct *mm = current->mm;
> > - struct vm_area_struct *vma;
> > - int ret = 0;
> > - int err;
> > - int locked;
> > -
> > - if (nr_frames == 0)
> > - return 0;
> > -
> > - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > - nr_frames = vec->nr_allocated;
> > -
> > - down_read(&mm->mmap_sem);
> > - locked = 1;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - if (!vma) {
> > - ret = -EFAULT;
> > - goto out;
> > - }
> > - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > - vec->got_ref = true;
> > - vec->is_pfns = false;
> > - ret = get_user_pages_locked(current, mm, start, nr_frames,
> > - write, force, (struct page **)(vec->ptrs), &locked);
> > - goto out;
> > - }
> > -
> > - vec->got_ref = false;
> > - vec->is_pfns = true;
> > - do {
> > - unsigned long *nums = frame_vector_pfns(vec);
> > -
> > - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > - err = follow_pfn(vma, start, &nums[ret]);
> > - if (err) {
> > - if (ret == 0)
> > - ret = err;
> > - goto out;
> > - }
> > - start += PAGE_SIZE;
> > - ret++;
> > - }
> > - /*
> > - * We stop if we have enough pages or if VMA doesn't completely
> > - * cover the tail page.
> > - */
> > - if (ret >= nr_frames || start < vma->vm_end)
> > - break;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > -out:
> > - if (locked)
> > - up_read(&mm->mmap_sem);
> > - if (!ret)
> > - ret = -EFAULT;
> > - if (ret > 0)
> > - vec->nr_frames = ret;
> > - return ret;
> > -}
> > -EXPORT_SYMBOL(get_vaddr_frames);
> > -
> > -/**
> > - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > - * them
> > - * @vec: frame vector to put
> > - *
> > - * Drop references to pages if get_vaddr_frames() acquired them. We also
> > - * invalidate the frame vector so that it is prepared for the next call into
> > - * get_vaddr_frames().
> > - */
> > -void put_vaddr_frames(struct frame_vector *vec)
> > -{
> > - int i;
> > - struct page **pages;
> > -
> > - if (!vec->got_ref)
> > - goto out;
> > - pages = frame_vector_pages(vec);
> > - /*
> > - * frame_vector_pages() might needed to do a conversion when
> > - * get_vaddr_frames() got pages but vec was later converted to pfns.
> > - * But it shouldn't really fail to convert pfns back...
> > - */
> > - if (WARN_ON(IS_ERR(pages)))
> > - goto out;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - put_page(pages[i]);
> > - vec->got_ref = false;
> > -out:
> > - vec->nr_frames = 0;
> > -}
> > -EXPORT_SYMBOL(put_vaddr_frames);
> > -
> > -/**
> > - * frame_vector_to_pages - convert frame vector to contain page pointers
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of page pointers. If the conversion is
> > - * successful, return 0. Otherwise return an error. Note that we do not grab
> > - * page references for the page structures.
> > - */
> > -int frame_vector_to_pages(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (!vec->is_pfns)
> > - return 0;
> > - nums = frame_vector_pfns(vec);
> > - for (i = 0; i < vec->nr_frames; i++)
> > - if (!pfn_valid(nums[i]))
> > - return -EINVAL;
> > - pages = (struct page **)nums;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - pages[i] = pfn_to_page(nums[i]);
> > - vec->is_pfns = false;
> > - return 0;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pages);
> > -
> > -/**
> > - * frame_vector_to_pfns - convert frame vector to contain pfns
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of pfns.
> > - */
> > -void frame_vector_to_pfns(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (vec->is_pfns)
> > - return;
> > - pages = (struct page **)(vec->ptrs);
> > - nums = (unsigned long *)pages;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - nums[i] = page_to_pfn(pages[i]);
> > - vec->is_pfns = true;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pfns);
> > -
> > -/**
> > - * frame_vector_create() - allocate & initialize structure for pinned pfns
> > - * @nr_frames: number of pfns slots we should reserve
> > - *
> > - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > - * pfns.
> > - */
> > -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > -{
> > - struct frame_vector *vec;
> > - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > -
> > - if (WARN_ON_ONCE(nr_frames == 0))
> > - return NULL;
> > - /*
> > - * This is absurdly high. It's here just to avoid strange effects when
> > - * arithmetics overflows.
> > - */
> > - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > - return NULL;
> > - /*
> > - * Avoid higher order allocations, use vmalloc instead. It should
> > - * be rare anyway.
> > - */
> > - if (size <= PAGE_SIZE)
> > - vec = kmalloc(size, GFP_KERNEL);
> > - else
> > - vec = vmalloc(size);
> > - if (!vec)
> > - return NULL;
> > - vec->nr_allocated = nr_frames;
> > - vec->nr_frames = 0;
> > - return vec;
> > -}
> > -EXPORT_SYMBOL(frame_vector_create);
> > -
> > -/**
> > - * frame_vector_destroy() - free memory allocated to carry frame vector
> > - * @vec: Frame vector to free
> > - *
> > - * Free structure allocated by frame_vector_create() to carry frames.
> > - */
> > -void frame_vector_destroy(struct frame_vector *vec)
> > -{
> > - /* Make sure put_vaddr_frames() got called properly... */
> > - VM_BUG_ON(vec->nr_frames > 0);
> > - if (!is_vmalloc_addr(vec))
> > - kfree(vec);
> > - else
> > - vfree(vec);
> > -}
> > -EXPORT_SYMBOL(frame_vector_destroy);
> > -
> > /**
> > * get_dump_page() - pin user page in memory while writing it to core dump
> > * @addr: user address
> > --
> > 2.4.2
> >
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-18 13:44 ` Jan Kara
0 siblings, 0 replies; 35+ messages in thread
From: Jan Kara @ 2015-06-18 13:44 UTC (permalink / raw)
To: Josh Triplett
Cc: Mauro Carvalho Chehab, Andrew Morton, Jan Kara,
Linux Media Mailing List, Mauro Carvalho Chehab, Inki Dae,
Joonyoung Shim, Seung-Woo Kim, Kyungmin Park, David Airlie,
Kukjin Kim, Hans Verkuil, Paul Bolle, Randy Dunlap, Jiri Kosina,
Geert Uytterhoeven, Mark Brown, Dan Streetman, Joonsoo Kim,
Minchan Kim, Paul E. McKenney, Steve Capper, Sasha Levin,
Ganesh Mahendran, Christoph Jaeger, Michal Hocko,
Johannes Weiner, Andrey Ryabinin, Konstantin Khlebnikov,
Matthew Wilcox, Al Viro, Kirill A. Shutemov,
Christian Borntraeger, Andrea Arcangeli, Paul Cassella,
Aneesh Kumar K.V, Naoya Horiguchi, dri-devel, linux-arm-kernel,
linux-samsung-soc, linux-mm
On Wed 10-06-15 09:37:20, Josh Triplett wrote:
> On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> > From: Jan Kara <jack@suse.cz>
> >
> > get_vaddr_frames() is used by relatively rare drivers so hide it and the
> > related functions behind a config option that is selected only by
> > drivers that need the infrastructure.
> >
> > Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> >
> > Signed-off-by: Jan Kara <jack@suse.cz>
> > Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>
> Seems sensible to me.
>
> Since this patch makes the kernel smaller, can you include the delta
> from bloat-o-meter between allnoconfig with and without this patch?
The results are:
add/remove: 0/6 grow/shrink: 0/0 up/down: 0/-868 (-868)
function old new delta
frame_vector_destroy 55 - -55
frame_vector_to_pfns 56 - -56
frame_vector_create 81 - -81
put_vaddr_frames 93 - -93
frame_vector_to_pages 98 - -98
get_vaddr_frames 485 - -485
I've added it to the changelog of the patch.
> Also, I assume you've compile-tested the kernel with allyesconfig minus
> the three options that now have "select FRAME_VECTOR", to make sure it
> builds?
I did not because the config option VIDEOBUF2_MEMOPS is a virtual one
selected transitively by quite a few video drivers and I didn't bother with
tracking down all of them... But since that config option guards
compilation of the code I modified I'm pretty confident I got it right.
Honza
> > create mode 100644 mm/frame_vector.c
> >
> > diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> > index 0a6780367d28..fc678289cf79 100644
> > --- a/drivers/gpu/drm/exynos/Kconfig
> > +++ b/drivers/gpu/drm/exynos/Kconfig
> > @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> > config DRM_EXYNOS_G2D
> > bool "Exynos DRM G2D"
> > depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> > + select FRAME_VECTOR
> > help
> > Choose this option if you want to use Exynos G2D for DRM.
> >
> > diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> > index dc2aaab54aef..217d613b0fe7 100644
> > --- a/drivers/media/platform/omap/Kconfig
> > +++ b/drivers/media/platform/omap/Kconfig
> > @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> > select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> > select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> > select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> > + select FRAME_VECTOR
> > default n
> > ---help---
> > V4L2 Display driver support for OMAP2/3 based boards.
> > diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> > index f7a01a72eb9e..f38f6e387f04 100644
> > --- a/drivers/media/v4l2-core/Kconfig
> > +++ b/drivers/media/v4l2-core/Kconfig
> > @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
> >
> > config VIDEOBUF2_MEMOPS
> > tristate
> > + select FRAME_VECTOR
> >
> > config VIDEOBUF2_DMA_CONTIG
> > tristate
> > diff --git a/mm/Kconfig b/mm/Kconfig
> > index 390214da4546..2ca52e9986f0 100644
> > --- a/mm/Kconfig
> > +++ b/mm/Kconfig
> > @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> > changed to a smaller value in which case that is used.
> >
> > A sane initial value is 80 MB.
> > +
> > +config FRAME_VECTOR
> > + bool
> > diff --git a/mm/Makefile b/mm/Makefile
> > index 98c4eaeabdcb..be5d5c866305 100644
> > --- a/mm/Makefile
> > +++ b/mm/Makefile
> > @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> > obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> > obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> > obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> > +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> > diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> > new file mode 100644
> > index 000000000000..31a2bd5f41d5
> > --- /dev/null
> > +++ b/mm/frame_vector.c
> > @@ -0,0 +1,232 @@
> > +#include <linux/kernel.h>
> > +#include <linux/errno.h>
> > +#include <linux/err.h>
> > +#include <linux/mm.h>
> > +#include <linux/slab.h>
> > +#include <linux/pagemap.h>
> > +#include <linux/sched.h>
> > +
> > +/*
> > + * get_vaddr_frames() - map virtual addresses to pfns
> > + * @start: starting user address
> > + * @nr_frames: number of pages / pfns from start to map
> > + * @write: whether pages will be written to by the caller
> > + * @force: whether to force write access even if user mapping is
> > + * readonly. See description of the same argument of
> > + get_user_pages().
> > + * @vec: structure which receives pages / pfns of the addresses mapped.
> > + * It should have space for at least nr_frames entries.
> > + *
> > + * This function maps virtual addresses from @start and fills @vec structure
> > + * with page frame numbers or page pointers to corresponding pages (choice
> > + * depends on the type of the vma underlying the virtual address). If @start
> > + * belongs to a normal vma, the function grabs reference to each of the pages
> > + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > + * touch page structures and the caller must make sure pfns aren't reused for
> > + * anything else while he is using them.
> > + *
> > + * The function returns number of pages mapped which may be less than
> > + * @nr_frames. In particular we stop mapping if there are more vmas of
> > + * different type underlying the specified range of virtual addresses.
> > + * When the function isn't able to map a single page, it returns error.
> > + *
> > + * This function takes care of grabbing mmap_sem as necessary.
> > + */
> > +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > + bool write, bool force, struct frame_vector *vec)
> > +{
> > + struct mm_struct *mm = current->mm;
> > + struct vm_area_struct *vma;
> > + int ret = 0;
> > + int err;
> > + int locked;
> > +
> > + if (nr_frames == 0)
> > + return 0;
> > +
> > + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > + nr_frames = vec->nr_allocated;
> > +
> > + down_read(&mm->mmap_sem);
> > + locked = 1;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + if (!vma) {
> > + ret = -EFAULT;
> > + goto out;
> > + }
> > + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > + vec->got_ref = true;
> > + vec->is_pfns = false;
> > + ret = get_user_pages_locked(current, mm, start, nr_frames,
> > + write, force, (struct page **)(vec->ptrs), &locked);
> > + goto out;
> > + }
> > +
> > + vec->got_ref = false;
> > + vec->is_pfns = true;
> > + do {
> > + unsigned long *nums = frame_vector_pfns(vec);
> > +
> > + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > + err = follow_pfn(vma, start, &nums[ret]);
> > + if (err) {
> > + if (ret == 0)
> > + ret = err;
> > + goto out;
> > + }
> > + start += PAGE_SIZE;
> > + ret++;
> > + }
> > + /*
> > + * We stop if we have enough pages or if VMA doesn't completely
> > + * cover the tail page.
> > + */
> > + if (ret >= nr_frames || start < vma->vm_end)
> > + break;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > +out:
> > + if (locked)
> > + up_read(&mm->mmap_sem);
> > + if (!ret)
> > + ret = -EFAULT;
> > + if (ret > 0)
> > + vec->nr_frames = ret;
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(get_vaddr_frames);
> > +
> > +/**
> > + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > + * them
> > + * @vec: frame vector to put
> > + *
> > + * Drop references to pages if get_vaddr_frames() acquired them. We also
> > + * invalidate the frame vector so that it is prepared for the next call into
> > + * get_vaddr_frames().
> > + */
> > +void put_vaddr_frames(struct frame_vector *vec)
> > +{
> > + int i;
> > + struct page **pages;
> > +
> > + if (!vec->got_ref)
> > + goto out;
> > + pages = frame_vector_pages(vec);
> > + /*
> > + * frame_vector_pages() might needed to do a conversion when
> > + * get_vaddr_frames() got pages but vec was later converted to pfns.
> > + * But it shouldn't really fail to convert pfns back...
> > + */
> > + if (WARN_ON(IS_ERR(pages)))
> > + goto out;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + put_page(pages[i]);
> > + vec->got_ref = false;
> > +out:
> > + vec->nr_frames = 0;
> > +}
> > +EXPORT_SYMBOL(put_vaddr_frames);
> > +
> > +/**
> > + * frame_vector_to_pages - convert frame vector to contain page pointers
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of page pointers. If the conversion is
> > + * successful, return 0. Otherwise return an error. Note that we do not grab
> > + * page references for the page structures.
> > + */
> > +int frame_vector_to_pages(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (!vec->is_pfns)
> > + return 0;
> > + nums = frame_vector_pfns(vec);
> > + for (i = 0; i < vec->nr_frames; i++)
> > + if (!pfn_valid(nums[i]))
> > + return -EINVAL;
> > + pages = (struct page **)nums;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + pages[i] = pfn_to_page(nums[i]);
> > + vec->is_pfns = false;
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pages);
> > +
> > +/**
> > + * frame_vector_to_pfns - convert frame vector to contain pfns
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of pfns.
> > + */
> > +void frame_vector_to_pfns(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (vec->is_pfns)
> > + return;
> > + pages = (struct page **)(vec->ptrs);
> > + nums = (unsigned long *)pages;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + nums[i] = page_to_pfn(pages[i]);
> > + vec->is_pfns = true;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pfns);
> > +
> > +/**
> > + * frame_vector_create() - allocate & initialize structure for pinned pfns
> > + * @nr_frames: number of pfns slots we should reserve
> > + *
> > + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > + * pfns.
> > + */
> > +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > +{
> > + struct frame_vector *vec;
> > + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > +
> > + if (WARN_ON_ONCE(nr_frames == 0))
> > + return NULL;
> > + /*
> > + * This is absurdly high. It's here just to avoid strange effects when
> > + * arithmetics overflows.
> > + */
> > + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > + return NULL;
> > + /*
> > + * Avoid higher order allocations, use vmalloc instead. It should
> > + * be rare anyway.
> > + */
> > + if (size <= PAGE_SIZE)
> > + vec = kmalloc(size, GFP_KERNEL);
> > + else
> > + vec = vmalloc(size);
> > + if (!vec)
> > + return NULL;
> > + vec->nr_allocated = nr_frames;
> > + vec->nr_frames = 0;
> > + return vec;
> > +}
> > +EXPORT_SYMBOL(frame_vector_create);
> > +
> > +/**
> > + * frame_vector_destroy() - free memory allocated to carry frame vector
> > + * @vec: Frame vector to free
> > + *
> > + * Free structure allocated by frame_vector_create() to carry frames.
> > + */
> > +void frame_vector_destroy(struct frame_vector *vec)
> > +{
> > + /* Make sure put_vaddr_frames() got called properly... */
> > + VM_BUG_ON(vec->nr_frames > 0);
> > + if (!is_vmalloc_addr(vec))
> > + kfree(vec);
> > + else
> > + vfree(vec);
> > +}
> > +EXPORT_SYMBOL(frame_vector_destroy);
> > diff --git a/mm/gup.c b/mm/gup.c
> > index 9d7f4fde30cb..222d57e335f9 100644
> > --- a/mm/gup.c
> > +++ b/mm/gup.c
> > @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> > return ret; /* 0 or negative error code */
> > }
> >
> > -/*
> > - * get_vaddr_frames() - map virtual addresses to pfns
> > - * @start: starting user address
> > - * @nr_frames: number of pages / pfns from start to map
> > - * @write: whether pages will be written to by the caller
> > - * @force: whether to force write access even if user mapping is
> > - * readonly. See description of the same argument of
> > - get_user_pages().
> > - * @vec: structure which receives pages / pfns of the addresses mapped.
> > - * It should have space for at least nr_frames entries.
> > - *
> > - * This function maps virtual addresses from @start and fills @vec structure
> > - * with page frame numbers or page pointers to corresponding pages (choice
> > - * depends on the type of the vma underlying the virtual address). If @start
> > - * belongs to a normal vma, the function grabs reference to each of the pages
> > - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > - * touch page structures and the caller must make sure pfns aren't reused for
> > - * anything else while he is using them.
> > - *
> > - * The function returns number of pages mapped which may be less than
> > - * @nr_frames. In particular we stop mapping if there are more vmas of
> > - * different type underlying the specified range of virtual addresses.
> > - * When the function isn't able to map a single page, it returns error.
> > - *
> > - * This function takes care of grabbing mmap_sem as necessary.
> > - */
> > -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > - bool write, bool force, struct frame_vector *vec)
> > -{
> > - struct mm_struct *mm = current->mm;
> > - struct vm_area_struct *vma;
> > - int ret = 0;
> > - int err;
> > - int locked;
> > -
> > - if (nr_frames == 0)
> > - return 0;
> > -
> > - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > - nr_frames = vec->nr_allocated;
> > -
> > - down_read(&mm->mmap_sem);
> > - locked = 1;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - if (!vma) {
> > - ret = -EFAULT;
> > - goto out;
> > - }
> > - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > - vec->got_ref = true;
> > - vec->is_pfns = false;
> > - ret = get_user_pages_locked(current, mm, start, nr_frames,
> > - write, force, (struct page **)(vec->ptrs), &locked);
> > - goto out;
> > - }
> > -
> > - vec->got_ref = false;
> > - vec->is_pfns = true;
> > - do {
> > - unsigned long *nums = frame_vector_pfns(vec);
> > -
> > - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > - err = follow_pfn(vma, start, &nums[ret]);
> > - if (err) {
> > - if (ret == 0)
> > - ret = err;
> > - goto out;
> > - }
> > - start += PAGE_SIZE;
> > - ret++;
> > - }
> > - /*
> > - * We stop if we have enough pages or if VMA doesn't completely
> > - * cover the tail page.
> > - */
> > - if (ret >= nr_frames || start < vma->vm_end)
> > - break;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > -out:
> > - if (locked)
> > - up_read(&mm->mmap_sem);
> > - if (!ret)
> > - ret = -EFAULT;
> > - if (ret > 0)
> > - vec->nr_frames = ret;
> > - return ret;
> > -}
> > -EXPORT_SYMBOL(get_vaddr_frames);
> > -
> > -/**
> > - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > - * them
> > - * @vec: frame vector to put
> > - *
> > - * Drop references to pages if get_vaddr_frames() acquired them. We also
> > - * invalidate the frame vector so that it is prepared for the next call into
> > - * get_vaddr_frames().
> > - */
> > -void put_vaddr_frames(struct frame_vector *vec)
> > -{
> > - int i;
> > - struct page **pages;
> > -
> > - if (!vec->got_ref)
> > - goto out;
> > - pages = frame_vector_pages(vec);
> > - /*
> > - * frame_vector_pages() might needed to do a conversion when
> > - * get_vaddr_frames() got pages but vec was later converted to pfns.
> > - * But it shouldn't really fail to convert pfns back...
> > - */
> > - if (WARN_ON(IS_ERR(pages)))
> > - goto out;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - put_page(pages[i]);
> > - vec->got_ref = false;
> > -out:
> > - vec->nr_frames = 0;
> > -}
> > -EXPORT_SYMBOL(put_vaddr_frames);
> > -
> > -/**
> > - * frame_vector_to_pages - convert frame vector to contain page pointers
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of page pointers. If the conversion is
> > - * successful, return 0. Otherwise return an error. Note that we do not grab
> > - * page references for the page structures.
> > - */
> > -int frame_vector_to_pages(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (!vec->is_pfns)
> > - return 0;
> > - nums = frame_vector_pfns(vec);
> > - for (i = 0; i < vec->nr_frames; i++)
> > - if (!pfn_valid(nums[i]))
> > - return -EINVAL;
> > - pages = (struct page **)nums;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - pages[i] = pfn_to_page(nums[i]);
> > - vec->is_pfns = false;
> > - return 0;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pages);
> > -
> > -/**
> > - * frame_vector_to_pfns - convert frame vector to contain pfns
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of pfns.
> > - */
> > -void frame_vector_to_pfns(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (vec->is_pfns)
> > - return;
> > - pages = (struct page **)(vec->ptrs);
> > - nums = (unsigned long *)pages;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - nums[i] = page_to_pfn(pages[i]);
> > - vec->is_pfns = true;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pfns);
> > -
> > -/**
> > - * frame_vector_create() - allocate & initialize structure for pinned pfns
> > - * @nr_frames: number of pfns slots we should reserve
> > - *
> > - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > - * pfns.
> > - */
> > -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > -{
> > - struct frame_vector *vec;
> > - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > -
> > - if (WARN_ON_ONCE(nr_frames == 0))
> > - return NULL;
> > - /*
> > - * This is absurdly high. It's here just to avoid strange effects when
> > - * arithmetics overflows.
> > - */
> > - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > - return NULL;
> > - /*
> > - * Avoid higher order allocations, use vmalloc instead. It should
> > - * be rare anyway.
> > - */
> > - if (size <= PAGE_SIZE)
> > - vec = kmalloc(size, GFP_KERNEL);
> > - else
> > - vec = vmalloc(size);
> > - if (!vec)
> > - return NULL;
> > - vec->nr_allocated = nr_frames;
> > - vec->nr_frames = 0;
> > - return vec;
> > -}
> > -EXPORT_SYMBOL(frame_vector_create);
> > -
> > -/**
> > - * frame_vector_destroy() - free memory allocated to carry frame vector
> > - * @vec: Frame vector to free
> > - *
> > - * Free structure allocated by frame_vector_create() to carry frames.
> > - */
> > -void frame_vector_destroy(struct frame_vector *vec)
> > -{
> > - /* Make sure put_vaddr_frames() got called properly... */
> > - VM_BUG_ON(vec->nr_frames > 0);
> > - if (!is_vmalloc_addr(vec))
> > - kfree(vec);
> > - else
> > - vfree(vec);
> > -}
> > -EXPORT_SYMBOL(frame_vector_destroy);
> > -
> > /**
> > * get_dump_page() - pin user page in memory while writing it to core dump
> > * @addr: user address
> > --
> > 2.4.2
> >
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR
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^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 9/9] [media] mm: Move get_vaddr_frames() behind a config option
@ 2015-06-18 13:44 ` Jan Kara
0 siblings, 0 replies; 35+ messages in thread
From: Jan Kara @ 2015-06-18 13:44 UTC (permalink / raw)
To: Josh Triplett
Cc: Mauro Carvalho Chehab, Andrew Morton, Jan Kara,
Linux Media Mailing List, Mauro Carvalho Chehab, Inki Dae,
Joonyoung Shim, Seung-Woo Kim, Kyungmin Park, David Airlie,
Kukjin Kim, Hans Verkuil, Paul Bolle, Randy Dunlap, Jiri Kosina,
Geert Uytterhoeven, Mark Brown, Dan Streetman, Joonsoo Kim,
Minchan Kim, Paul E. McKenney, Steve Capper, Sasha Levin
On Wed 10-06-15 09:37:20, Josh Triplett wrote:
> On Wed, Jun 10, 2015 at 06:20:52AM -0300, Mauro Carvalho Chehab wrote:
> > From: Jan Kara <jack@suse.cz>
> >
> > get_vaddr_frames() is used by relatively rare drivers so hide it and the
> > related functions behind a config option that is selected only by
> > drivers that need the infrastructure.
> >
> > Suggested-by: Andrew Morton <akpm@linux-foundation.org>
> >
> > Signed-off-by: Jan Kara <jack@suse.cz>
> > Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>
> Seems sensible to me.
>
> Since this patch makes the kernel smaller, can you include the delta
> from bloat-o-meter between allnoconfig with and without this patch?
The results are:
add/remove: 0/6 grow/shrink: 0/0 up/down: 0/-868 (-868)
function old new delta
frame_vector_destroy 55 - -55
frame_vector_to_pfns 56 - -56
frame_vector_create 81 - -81
put_vaddr_frames 93 - -93
frame_vector_to_pages 98 - -98
get_vaddr_frames 485 - -485
I've added it to the changelog of the patch.
> Also, I assume you've compile-tested the kernel with allyesconfig minus
> the three options that now have "select FRAME_VECTOR", to make sure it
> builds?
I did not because the config option VIDEOBUF2_MEMOPS is a virtual one
selected transitively by quite a few video drivers and I didn't bother with
tracking down all of them... But since that config option guards
compilation of the code I modified I'm pretty confident I got it right.
Honza
> > create mode 100644 mm/frame_vector.c
> >
> > diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
> > index 0a6780367d28..fc678289cf79 100644
> > --- a/drivers/gpu/drm/exynos/Kconfig
> > +++ b/drivers/gpu/drm/exynos/Kconfig
> > @@ -71,6 +71,7 @@ config DRM_EXYNOS_VIDI
> > config DRM_EXYNOS_G2D
> > bool "Exynos DRM G2D"
> > depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
> > + select FRAME_VECTOR
> > help
> > Choose this option if you want to use Exynos G2D for DRM.
> >
> > diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig
> > index dc2aaab54aef..217d613b0fe7 100644
> > --- a/drivers/media/platform/omap/Kconfig
> > +++ b/drivers/media/platform/omap/Kconfig
> > @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT
> > select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS
> > select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3
> > select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB
> > + select FRAME_VECTOR
> > default n
> > ---help---
> > V4L2 Display driver support for OMAP2/3 based boards.
> > diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> > index f7a01a72eb9e..f38f6e387f04 100644
> > --- a/drivers/media/v4l2-core/Kconfig
> > +++ b/drivers/media/v4l2-core/Kconfig
> > @@ -73,6 +73,7 @@ config VIDEOBUF2_CORE
> >
> > config VIDEOBUF2_MEMOPS
> > tristate
> > + select FRAME_VECTOR
> >
> > config VIDEOBUF2_DMA_CONTIG
> > tristate
> > diff --git a/mm/Kconfig b/mm/Kconfig
> > index 390214da4546..2ca52e9986f0 100644
> > --- a/mm/Kconfig
> > +++ b/mm/Kconfig
> > @@ -635,3 +635,6 @@ config MAX_STACK_SIZE_MB
> > changed to a smaller value in which case that is used.
> >
> > A sane initial value is 80 MB.
> > +
> > +config FRAME_VECTOR
> > + bool
> > diff --git a/mm/Makefile b/mm/Makefile
> > index 98c4eaeabdcb..be5d5c866305 100644
> > --- a/mm/Makefile
> > +++ b/mm/Makefile
> > @@ -78,3 +78,4 @@ obj-$(CONFIG_CMA) += cma.o
> > obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
> > obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
> > obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
> > +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
> > diff --git a/mm/frame_vector.c b/mm/frame_vector.c
> > new file mode 100644
> > index 000000000000..31a2bd5f41d5
> > --- /dev/null
> > +++ b/mm/frame_vector.c
> > @@ -0,0 +1,232 @@
> > +#include <linux/kernel.h>
> > +#include <linux/errno.h>
> > +#include <linux/err.h>
> > +#include <linux/mm.h>
> > +#include <linux/slab.h>
> > +#include <linux/pagemap.h>
> > +#include <linux/sched.h>
> > +
> > +/*
> > + * get_vaddr_frames() - map virtual addresses to pfns
> > + * @start: starting user address
> > + * @nr_frames: number of pages / pfns from start to map
> > + * @write: whether pages will be written to by the caller
> > + * @force: whether to force write access even if user mapping is
> > + * readonly. See description of the same argument of
> > + get_user_pages().
> > + * @vec: structure which receives pages / pfns of the addresses mapped.
> > + * It should have space for at least nr_frames entries.
> > + *
> > + * This function maps virtual addresses from @start and fills @vec structure
> > + * with page frame numbers or page pointers to corresponding pages (choice
> > + * depends on the type of the vma underlying the virtual address). If @start
> > + * belongs to a normal vma, the function grabs reference to each of the pages
> > + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > + * touch page structures and the caller must make sure pfns aren't reused for
> > + * anything else while he is using them.
> > + *
> > + * The function returns number of pages mapped which may be less than
> > + * @nr_frames. In particular we stop mapping if there are more vmas of
> > + * different type underlying the specified range of virtual addresses.
> > + * When the function isn't able to map a single page, it returns error.
> > + *
> > + * This function takes care of grabbing mmap_sem as necessary.
> > + */
> > +int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > + bool write, bool force, struct frame_vector *vec)
> > +{
> > + struct mm_struct *mm = current->mm;
> > + struct vm_area_struct *vma;
> > + int ret = 0;
> > + int err;
> > + int locked;
> > +
> > + if (nr_frames == 0)
> > + return 0;
> > +
> > + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > + nr_frames = vec->nr_allocated;
> > +
> > + down_read(&mm->mmap_sem);
> > + locked = 1;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + if (!vma) {
> > + ret = -EFAULT;
> > + goto out;
> > + }
> > + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > + vec->got_ref = true;
> > + vec->is_pfns = false;
> > + ret = get_user_pages_locked(current, mm, start, nr_frames,
> > + write, force, (struct page **)(vec->ptrs), &locked);
> > + goto out;
> > + }
> > +
> > + vec->got_ref = false;
> > + vec->is_pfns = true;
> > + do {
> > + unsigned long *nums = frame_vector_pfns(vec);
> > +
> > + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > + err = follow_pfn(vma, start, &nums[ret]);
> > + if (err) {
> > + if (ret == 0)
> > + ret = err;
> > + goto out;
> > + }
> > + start += PAGE_SIZE;
> > + ret++;
> > + }
> > + /*
> > + * We stop if we have enough pages or if VMA doesn't completely
> > + * cover the tail page.
> > + */
> > + if (ret >= nr_frames || start < vma->vm_end)
> > + break;
> > + vma = find_vma_intersection(mm, start, start + 1);
> > + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > +out:
> > + if (locked)
> > + up_read(&mm->mmap_sem);
> > + if (!ret)
> > + ret = -EFAULT;
> > + if (ret > 0)
> > + vec->nr_frames = ret;
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(get_vaddr_frames);
> > +
> > +/**
> > + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > + * them
> > + * @vec: frame vector to put
> > + *
> > + * Drop references to pages if get_vaddr_frames() acquired them. We also
> > + * invalidate the frame vector so that it is prepared for the next call into
> > + * get_vaddr_frames().
> > + */
> > +void put_vaddr_frames(struct frame_vector *vec)
> > +{
> > + int i;
> > + struct page **pages;
> > +
> > + if (!vec->got_ref)
> > + goto out;
> > + pages = frame_vector_pages(vec);
> > + /*
> > + * frame_vector_pages() might needed to do a conversion when
> > + * get_vaddr_frames() got pages but vec was later converted to pfns.
> > + * But it shouldn't really fail to convert pfns back...
> > + */
> > + if (WARN_ON(IS_ERR(pages)))
> > + goto out;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + put_page(pages[i]);
> > + vec->got_ref = false;
> > +out:
> > + vec->nr_frames = 0;
> > +}
> > +EXPORT_SYMBOL(put_vaddr_frames);
> > +
> > +/**
> > + * frame_vector_to_pages - convert frame vector to contain page pointers
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of page pointers. If the conversion is
> > + * successful, return 0. Otherwise return an error. Note that we do not grab
> > + * page references for the page structures.
> > + */
> > +int frame_vector_to_pages(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (!vec->is_pfns)
> > + return 0;
> > + nums = frame_vector_pfns(vec);
> > + for (i = 0; i < vec->nr_frames; i++)
> > + if (!pfn_valid(nums[i]))
> > + return -EINVAL;
> > + pages = (struct page **)nums;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + pages[i] = pfn_to_page(nums[i]);
> > + vec->is_pfns = false;
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pages);
> > +
> > +/**
> > + * frame_vector_to_pfns - convert frame vector to contain pfns
> > + * @vec: frame vector to convert
> > + *
> > + * Convert @vec to contain array of pfns.
> > + */
> > +void frame_vector_to_pfns(struct frame_vector *vec)
> > +{
> > + int i;
> > + unsigned long *nums;
> > + struct page **pages;
> > +
> > + if (vec->is_pfns)
> > + return;
> > + pages = (struct page **)(vec->ptrs);
> > + nums = (unsigned long *)pages;
> > + for (i = 0; i < vec->nr_frames; i++)
> > + nums[i] = page_to_pfn(pages[i]);
> > + vec->is_pfns = true;
> > +}
> > +EXPORT_SYMBOL(frame_vector_to_pfns);
> > +
> > +/**
> > + * frame_vector_create() - allocate & initialize structure for pinned pfns
> > + * @nr_frames: number of pfns slots we should reserve
> > + *
> > + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > + * pfns.
> > + */
> > +struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > +{
> > + struct frame_vector *vec;
> > + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > +
> > + if (WARN_ON_ONCE(nr_frames == 0))
> > + return NULL;
> > + /*
> > + * This is absurdly high. It's here just to avoid strange effects when
> > + * arithmetics overflows.
> > + */
> > + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > + return NULL;
> > + /*
> > + * Avoid higher order allocations, use vmalloc instead. It should
> > + * be rare anyway.
> > + */
> > + if (size <= PAGE_SIZE)
> > + vec = kmalloc(size, GFP_KERNEL);
> > + else
> > + vec = vmalloc(size);
> > + if (!vec)
> > + return NULL;
> > + vec->nr_allocated = nr_frames;
> > + vec->nr_frames = 0;
> > + return vec;
> > +}
> > +EXPORT_SYMBOL(frame_vector_create);
> > +
> > +/**
> > + * frame_vector_destroy() - free memory allocated to carry frame vector
> > + * @vec: Frame vector to free
> > + *
> > + * Free structure allocated by frame_vector_create() to carry frames.
> > + */
> > +void frame_vector_destroy(struct frame_vector *vec)
> > +{
> > + /* Make sure put_vaddr_frames() got called properly... */
> > + VM_BUG_ON(vec->nr_frames > 0);
> > + if (!is_vmalloc_addr(vec))
> > + kfree(vec);
> > + else
> > + vfree(vec);
> > +}
> > +EXPORT_SYMBOL(frame_vector_destroy);
> > diff --git a/mm/gup.c b/mm/gup.c
> > index 9d7f4fde30cb..222d57e335f9 100644
> > --- a/mm/gup.c
> > +++ b/mm/gup.c
> > @@ -937,231 +937,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
> > return ret; /* 0 or negative error code */
> > }
> >
> > -/*
> > - * get_vaddr_frames() - map virtual addresses to pfns
> > - * @start: starting user address
> > - * @nr_frames: number of pages / pfns from start to map
> > - * @write: whether pages will be written to by the caller
> > - * @force: whether to force write access even if user mapping is
> > - * readonly. See description of the same argument of
> > - get_user_pages().
> > - * @vec: structure which receives pages / pfns of the addresses mapped.
> > - * It should have space for at least nr_frames entries.
> > - *
> > - * This function maps virtual addresses from @start and fills @vec structure
> > - * with page frame numbers or page pointers to corresponding pages (choice
> > - * depends on the type of the vma underlying the virtual address). If @start
> > - * belongs to a normal vma, the function grabs reference to each of the pages
> > - * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
> > - * touch page structures and the caller must make sure pfns aren't reused for
> > - * anything else while he is using them.
> > - *
> > - * The function returns number of pages mapped which may be less than
> > - * @nr_frames. In particular we stop mapping if there are more vmas of
> > - * different type underlying the specified range of virtual addresses.
> > - * When the function isn't able to map a single page, it returns error.
> > - *
> > - * This function takes care of grabbing mmap_sem as necessary.
> > - */
> > -int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
> > - bool write, bool force, struct frame_vector *vec)
> > -{
> > - struct mm_struct *mm = current->mm;
> > - struct vm_area_struct *vma;
> > - int ret = 0;
> > - int err;
> > - int locked;
> > -
> > - if (nr_frames == 0)
> > - return 0;
> > -
> > - if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
> > - nr_frames = vec->nr_allocated;
> > -
> > - down_read(&mm->mmap_sem);
> > - locked = 1;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - if (!vma) {
> > - ret = -EFAULT;
> > - goto out;
> > - }
> > - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
> > - vec->got_ref = true;
> > - vec->is_pfns = false;
> > - ret = get_user_pages_locked(current, mm, start, nr_frames,
> > - write, force, (struct page **)(vec->ptrs), &locked);
> > - goto out;
> > - }
> > -
> > - vec->got_ref = false;
> > - vec->is_pfns = true;
> > - do {
> > - unsigned long *nums = frame_vector_pfns(vec);
> > -
> > - while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
> > - err = follow_pfn(vma, start, &nums[ret]);
> > - if (err) {
> > - if (ret == 0)
> > - ret = err;
> > - goto out;
> > - }
> > - start += PAGE_SIZE;
> > - ret++;
> > - }
> > - /*
> > - * We stop if we have enough pages or if VMA doesn't completely
> > - * cover the tail page.
> > - */
> > - if (ret >= nr_frames || start < vma->vm_end)
> > - break;
> > - vma = find_vma_intersection(mm, start, start + 1);
> > - } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
> > -out:
> > - if (locked)
> > - up_read(&mm->mmap_sem);
> > - if (!ret)
> > - ret = -EFAULT;
> > - if (ret > 0)
> > - vec->nr_frames = ret;
> > - return ret;
> > -}
> > -EXPORT_SYMBOL(get_vaddr_frames);
> > -
> > -/**
> > - * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
> > - * them
> > - * @vec: frame vector to put
> > - *
> > - * Drop references to pages if get_vaddr_frames() acquired them. We also
> > - * invalidate the frame vector so that it is prepared for the next call into
> > - * get_vaddr_frames().
> > - */
> > -void put_vaddr_frames(struct frame_vector *vec)
> > -{
> > - int i;
> > - struct page **pages;
> > -
> > - if (!vec->got_ref)
> > - goto out;
> > - pages = frame_vector_pages(vec);
> > - /*
> > - * frame_vector_pages() might needed to do a conversion when
> > - * get_vaddr_frames() got pages but vec was later converted to pfns.
> > - * But it shouldn't really fail to convert pfns back...
> > - */
> > - if (WARN_ON(IS_ERR(pages)))
> > - goto out;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - put_page(pages[i]);
> > - vec->got_ref = false;
> > -out:
> > - vec->nr_frames = 0;
> > -}
> > -EXPORT_SYMBOL(put_vaddr_frames);
> > -
> > -/**
> > - * frame_vector_to_pages - convert frame vector to contain page pointers
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of page pointers. If the conversion is
> > - * successful, return 0. Otherwise return an error. Note that we do not grab
> > - * page references for the page structures.
> > - */
> > -int frame_vector_to_pages(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (!vec->is_pfns)
> > - return 0;
> > - nums = frame_vector_pfns(vec);
> > - for (i = 0; i < vec->nr_frames; i++)
> > - if (!pfn_valid(nums[i]))
> > - return -EINVAL;
> > - pages = (struct page **)nums;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - pages[i] = pfn_to_page(nums[i]);
> > - vec->is_pfns = false;
> > - return 0;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pages);
> > -
> > -/**
> > - * frame_vector_to_pfns - convert frame vector to contain pfns
> > - * @vec: frame vector to convert
> > - *
> > - * Convert @vec to contain array of pfns.
> > - */
> > -void frame_vector_to_pfns(struct frame_vector *vec)
> > -{
> > - int i;
> > - unsigned long *nums;
> > - struct page **pages;
> > -
> > - if (vec->is_pfns)
> > - return;
> > - pages = (struct page **)(vec->ptrs);
> > - nums = (unsigned long *)pages;
> > - for (i = 0; i < vec->nr_frames; i++)
> > - nums[i] = page_to_pfn(pages[i]);
> > - vec->is_pfns = true;
> > -}
> > -EXPORT_SYMBOL(frame_vector_to_pfns);
> > -
> > -/**
> > - * frame_vector_create() - allocate & initialize structure for pinned pfns
> > - * @nr_frames: number of pfns slots we should reserve
> > - *
> > - * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
> > - * pfns.
> > - */
> > -struct frame_vector *frame_vector_create(unsigned int nr_frames)
> > -{
> > - struct frame_vector *vec;
> > - int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
> > -
> > - if (WARN_ON_ONCE(nr_frames == 0))
> > - return NULL;
> > - /*
> > - * This is absurdly high. It's here just to avoid strange effects when
> > - * arithmetics overflows.
> > - */
> > - if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
> > - return NULL;
> > - /*
> > - * Avoid higher order allocations, use vmalloc instead. It should
> > - * be rare anyway.
> > - */
> > - if (size <= PAGE_SIZE)
> > - vec = kmalloc(size, GFP_KERNEL);
> > - else
> > - vec = vmalloc(size);
> > - if (!vec)
> > - return NULL;
> > - vec->nr_allocated = nr_frames;
> > - vec->nr_frames = 0;
> > - return vec;
> > -}
> > -EXPORT_SYMBOL(frame_vector_create);
> > -
> > -/**
> > - * frame_vector_destroy() - free memory allocated to carry frame vector
> > - * @vec: Frame vector to free
> > - *
> > - * Free structure allocated by frame_vector_create() to carry frames.
> > - */
> > -void frame_vector_destroy(struct frame_vector *vec)
> > -{
> > - /* Make sure put_vaddr_frames() got called properly... */
> > - VM_BUG_ON(vec->nr_frames > 0);
> > - if (!is_vmalloc_addr(vec))
> > - kfree(vec);
> > - else
> > - vfree(vec);
> > -}
> > -EXPORT_SYMBOL(frame_vector_destroy);
> > -
> > /**
> > * get_dump_page() - pin user page in memory while writing it to core dump
> > * @addr: user address
> > --
> > 2.4.2
> >
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR
^ permalink raw reply [flat|nested] 35+ messages in thread
* Re: [PATCH 0/9] Helper to abstract vma handling in media layer
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (8 preceding siblings ...)
2015-06-10 9:20 ` Mauro Carvalho Chehab
@ 2015-06-11 9:08 ` Hans Verkuil
2015-06-11 18:54 ` Andrew Morton
2015-06-15 7:41 ` Hans Verkuil
2015-06-22 22:04 ` Andrew Morton
11 siblings, 1 reply; 35+ messages in thread
From: Hans Verkuil @ 2015-06-11 9:08 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Andrew Morton
Cc: Linux Media Mailing List, Mauro Carvalho Chehab, Jan Kara
Hi Andrew,
I discovered a regression on a prerequisite patch merged in the media
tree that until solved prevents parts of this patch series from going in.
See: http://www.mail-archive.com/linux-media@vger.kernel.org/msg89538.html
Jan is on vacation, and I don't know if I have time this weekend to dig
into this, so the patch that caused the regression may have to be reverted
for 4.2 and the vb2 patches in this series postponed until the regression
problem is fixed.
Note that this is all v4l/vb2 related, the get_vaddr_frames helper is actually
fine and could be merged, it's just the vb2 patches in this patch series that
cannot be merged for now due to deadlocks.
Regards,
Hans
On 06/10/15 11:20, Mauro Carvalho Chehab wrote:
> Hi Andrew,
>
> I received this patch series with a new set of helper functions for
> mm, together with changes for media and DRM drivers.
>
> As this stuff is actually mm code, I prefer if this got merged via
> your tree.
>
> Could you please handle it? Please notice that patch 8 actually changes
> the exynos DRM driver, but it misses ack from DRM people.
>
> Regards,
> Mauro
>
> Jan Kara (9):
> mm: Provide new get_vaddr_frames() helper
> [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use
> get_vaddr_pfns()
> [media] vb2: Provide helpers for mapping virtual addresses
> [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame
> vector
> [media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame
> vector
> [media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector
> [media] media: vb2: Remove unused functions
> [media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use
> get_vaddr_frames()
> [media] mm: Move get_vaddr_frames() behind a config option
>
> drivers/gpu/drm/exynos/Kconfig | 1 +
> drivers/gpu/drm/exynos/exynos_drm_g2d.c | 95 ++++------
> drivers/gpu/drm/exynos/exynos_drm_gem.c | 97 -----------
> drivers/media/platform/omap/Kconfig | 1 +
> drivers/media/platform/omap/omap_vout.c | 69 ++++----
> drivers/media/v4l2-core/Kconfig | 1 +
> drivers/media/v4l2-core/videobuf2-dma-contig.c | 214 ++++-------------------
> drivers/media/v4l2-core/videobuf2-dma-sg.c | 99 ++---------
> drivers/media/v4l2-core/videobuf2-memops.c | 156 ++++++-----------
> drivers/media/v4l2-core/videobuf2-vmalloc.c | 92 ++++------
> include/linux/mm.h | 44 +++++
> include/media/videobuf2-memops.h | 11 +-
> mm/Kconfig | 3 +
> mm/Makefile | 1 +
> mm/frame_vector.c | 232 +++++++++++++++++++++++++
> mm/gup.c | 1 +
> 16 files changed, 486 insertions(+), 631 deletions(-)
> create mode 100644 mm/frame_vector.c
>
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 0/9] Helper to abstract vma handling in media layer
2015-06-11 9:08 ` [PATCH 0/9] Helper to abstract vma handling in media layer Hans Verkuil
@ 2015-06-11 18:54 ` Andrew Morton
2015-06-11 19:51 ` Hans Verkuil
0 siblings, 1 reply; 35+ messages in thread
From: Andrew Morton @ 2015-06-11 18:54 UTC (permalink / raw)
To: Hans Verkuil
Cc: Mauro Carvalho Chehab, Linux Media Mailing List,
Mauro Carvalho Chehab, Jan Kara
On Thu, 11 Jun 2015 11:08:47 +0200 Hans Verkuil <hverkuil@xs4all.nl> wrote:
> I discovered a regression on a prerequisite patch merged in the media
> tree that until solved prevents parts of this patch series from going in.
>
> See: http://www.mail-archive.com/linux-media@vger.kernel.org/msg89538.html
>
> Jan is on vacation, and I don't know if I have time this weekend to dig
> into this, so the patch that caused the regression may have to be reverted
> for 4.2 and the vb2 patches in this series postponed until the regression
> problem is fixed.
>
> Note that this is all v4l/vb2 related, the get_vaddr_frames helper is actually
> fine and could be merged, it's just the vb2 patches in this patch series that
> cannot be merged for now due to deadlocks.
OK, thanks. I'll just keep these patches on hold (in -next) until
advised otherwise?
^ permalink raw reply [flat|nested] 35+ messages in thread
* Re: [PATCH 0/9] Helper to abstract vma handling in media layer
2015-06-11 18:54 ` Andrew Morton
@ 2015-06-11 19:51 ` Hans Verkuil
0 siblings, 0 replies; 35+ messages in thread
From: Hans Verkuil @ 2015-06-11 19:51 UTC (permalink / raw)
To: Andrew Morton
Cc: Mauro Carvalho Chehab, Linux Media Mailing List,
Mauro Carvalho Chehab, Jan Kara
On 06/11/2015 08:54 PM, Andrew Morton wrote:
> On Thu, 11 Jun 2015 11:08:47 +0200 Hans Verkuil <hverkuil@xs4all.nl> wrote:
>
>> I discovered a regression on a prerequisite patch merged in the media
>> tree that until solved prevents parts of this patch series from going in.
>>
>> See: http://www.mail-archive.com/linux-media@vger.kernel.org/msg89538.html
>>
>> Jan is on vacation, and I don't know if I have time this weekend to dig
>> into this, so the patch that caused the regression may have to be reverted
>> for 4.2 and the vb2 patches in this series postponed until the regression
>> problem is fixed.
>>
>> Note that this is all v4l/vb2 related, the get_vaddr_frames helper is actually
>> fine and could be merged, it's just the vb2 patches in this patch series that
>> cannot be merged for now due to deadlocks.
>
> OK, thanks. I'll just keep these patches on hold (in -next) until
> advised otherwise?
Yes, that would be great.
Thanks,
Hans
^ permalink raw reply [flat|nested] 35+ messages in thread
* Re: [PATCH 0/9] Helper to abstract vma handling in media layer
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (9 preceding siblings ...)
2015-06-11 9:08 ` [PATCH 0/9] Helper to abstract vma handling in media layer Hans Verkuil
@ 2015-06-15 7:41 ` Hans Verkuil
2015-06-22 22:04 ` Andrew Morton
11 siblings, 0 replies; 35+ messages in thread
From: Hans Verkuil @ 2015-06-15 7:41 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Andrew Morton
Cc: Linux Media Mailing List, Mauro Carvalho Chehab, Jan Kara
On 06/10/2015 11:20 AM, Mauro Carvalho Chehab wrote:
> Hi Andrew,
>
> I received this patch series with a new set of helper functions for
> mm, together with changes for media and DRM drivers.
>
> As this stuff is actually mm code, I prefer if this got merged via
> your tree.
>
> Could you please handle it? Please notice that patch 8 actually changes
> the exynos DRM driver, but it misses ack from DRM people.
For the vb2 patches 3-7:
Nacked-by: Hans Verkuil <hans.verkuil@cisco.com>
Since the prerequisite patch "vb2: Push mmap_sem down to memops" caused
two regressions I want to postpone these other vb2 patches until that problem
is fixed first.
Jan, I leave it to you whether you want the non-vb2 patches to go in or not.
I don't think they are affected by this vb2 problem.
Regards,
Hans
>
> Regards,
> Mauro
>
> Jan Kara (9):
> mm: Provide new get_vaddr_frames() helper
> [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use
> get_vaddr_pfns()
> [media] vb2: Provide helpers for mapping virtual addresses
> [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame
> vector
> [media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame
> vector
> [media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector
> [media] media: vb2: Remove unused functions
> [media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use
> get_vaddr_frames()
> [media] mm: Move get_vaddr_frames() behind a config option
>
> drivers/gpu/drm/exynos/Kconfig | 1 +
> drivers/gpu/drm/exynos/exynos_drm_g2d.c | 95 ++++------
> drivers/gpu/drm/exynos/exynos_drm_gem.c | 97 -----------
> drivers/media/platform/omap/Kconfig | 1 +
> drivers/media/platform/omap/omap_vout.c | 69 ++++----
> drivers/media/v4l2-core/Kconfig | 1 +
> drivers/media/v4l2-core/videobuf2-dma-contig.c | 214 ++++-------------------
> drivers/media/v4l2-core/videobuf2-dma-sg.c | 99 ++---------
> drivers/media/v4l2-core/videobuf2-memops.c | 156 ++++++-----------
> drivers/media/v4l2-core/videobuf2-vmalloc.c | 92 ++++------
> include/linux/mm.h | 44 +++++
> include/media/videobuf2-memops.h | 11 +-
> mm/Kconfig | 3 +
> mm/Makefile | 1 +
> mm/frame_vector.c | 232 +++++++++++++++++++++++++
> mm/gup.c | 1 +
> 16 files changed, 486 insertions(+), 631 deletions(-)
> create mode 100644 mm/frame_vector.c
>
^ permalink raw reply [flat|nested] 35+ messages in thread* Re: [PATCH 0/9] Helper to abstract vma handling in media layer
2015-06-10 9:20 [PATCH 0/9] Helper to abstract vma handling in media layer Mauro Carvalho Chehab
` (10 preceding siblings ...)
2015-06-15 7:41 ` Hans Verkuil
@ 2015-06-22 22:04 ` Andrew Morton
11 siblings, 0 replies; 35+ messages in thread
From: Andrew Morton @ 2015-06-22 22:04 UTC (permalink / raw)
To: Mauro Carvalho Chehab; +Cc: Linux Media Mailing List, Mauro Carvalho Chehab
On Wed, 10 Jun 2015 06:20:43 -0300 Mauro Carvalho Chehab <mchehab@osg.samsung.com> wrote:
> I received this patch series with a new set of helper functions for
> mm, together with changes for media and DRM drivers.
>
> As this stuff is actually mm code, I prefer if this got merged via
> your tree.
>
> Could you please handle it? Please notice that patch 8 actually changes
> the exynos DRM driver, but it misses ack from DRM people.
I'm now getting large rejects from many of these patches. It seems
that someone has recently removed a patch from linux-next, and that
patch added down_read(mmap_sem) and up_read(mmap_sem) to the same
functions which this patch series is altering.
I started fixing them all up but I got bored, and I'm not very
confident in the end result.
It was a particularly bad time to be making these sorts of changes.
Does anyone know what's happening?
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^ permalink raw reply [flat|nested] 35+ messages in thread