From: Peter Xu <peterx@redhat.com>
To: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>,
Mike Kravetz <mike.kravetz@oracle.com>,
peterx@redhat.com, Jerome Glisse <jglisse@redhat.com>,
"Kirill A . Shutemov" <kirill@shutemov.name>,
Hugh Dickins <hughd@google.com>,
Axel Rasmussen <axelrasmussen@google.com>,
Matthew Wilcox <willy@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Nadav Amit <nadav.amit@gmail.com>
Subject: [PATCH RFC 19/30] hugetlb/userfaultfd: Take care of UFFDIO_COPY_MODE_WP
Date: Fri, 15 Jan 2021 12:08:56 -0500 [thread overview]
Message-ID: <20210115170907.24498-20-peterx@redhat.com> (raw)
In-Reply-To: <20210115170907.24498-1-peterx@redhat.com>
Firstly, pass the wp_copy variable into hugetlb_mcopy_atomic_pte() thoughout
the stack. Then, apply the UFFD_WP bit if UFFDIO_COPY_MODE_WP is with
UFFDIO_COPY. Introduce huge_pte_mkuffd_wp() for it.
Note that similar to how we've handled shmem, we'd better keep setting the
dirty bit even if UFFDIO_COPY_MODE_WP is provided, so that the core mm will
know this page contains valid data and never drop it.
Signed-off-by: Peter Xu <peterx@redhat.com>
---
include/asm-generic/hugetlb.h | 5 +++++
include/linux/hugetlb.h | 6 ++++--
mm/hugetlb.c | 9 +++++++--
mm/userfaultfd.c | 12 ++++++++----
4 files changed, 24 insertions(+), 8 deletions(-)
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index 8e1e6244a89d..548212eccbd6 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -27,6 +27,11 @@ static inline pte_t huge_pte_mkdirty(pte_t pte)
return pte_mkdirty(pte);
}
+static inline pte_t huge_pte_mkuffd_wp(pte_t pte)
+{
+ return pte_mkuffd_wp(pte);
+}
+
static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
{
return pte_modify(pte, newprot);
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index ebca2ef02212..bd061f7eedcb 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -138,7 +138,8 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, pte_t *dst_pte,
struct vm_area_struct *dst_vma,
unsigned long dst_addr,
unsigned long src_addr,
- struct page **pagep);
+ struct page **pagep,
+ bool wp_copy);
int hugetlb_reserve_pages(struct inode *inode, long from, long to,
struct vm_area_struct *vma,
vm_flags_t vm_flags);
@@ -313,7 +314,8 @@ static inline int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
struct vm_area_struct *dst_vma,
unsigned long dst_addr,
unsigned long src_addr,
- struct page **pagep)
+ struct page **pagep,
+ bool wp_copy)
{
BUG();
return 0;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index dcbbba53bd10..563b8f70537f 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4624,7 +4624,8 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
struct vm_area_struct *dst_vma,
unsigned long dst_addr,
unsigned long src_addr,
- struct page **pagep)
+ struct page **pagep,
+ bool wp_copy)
{
struct address_space *mapping;
pgoff_t idx;
@@ -4717,8 +4718,12 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
}
_dst_pte = make_huge_pte(dst_vma, page, dst_vma->vm_flags & VM_WRITE);
- if (dst_vma->vm_flags & VM_WRITE)
+ if (dst_vma->vm_flags & VM_WRITE) {
_dst_pte = huge_pte_mkdirty(_dst_pte);
+ if (wp_copy)
+ _dst_pte = huge_pte_mkuffd_wp(
+ huge_pte_wrprotect(_dst_pte));
+ }
_dst_pte = pte_mkyoung(_dst_pte);
set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte);
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 6d4b3b7c7f9f..b00e5e6b8b8b 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -207,7 +207,8 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
- bool zeropage)
+ bool zeropage,
+ bool wp_copy)
{
int vm_alloc_shared = dst_vma->vm_flags & VM_SHARED;
int vm_shared = dst_vma->vm_flags & VM_SHARED;
@@ -306,7 +307,8 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
}
err = hugetlb_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma,
- dst_addr, src_addr, &page);
+ dst_addr, src_addr, &page,
+ wp_copy);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
i_mmap_unlock_read(mapping);
@@ -408,7 +410,8 @@ extern ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
- bool zeropage);
+ bool zeropage,
+ bool wp_copy);
#endif /* CONFIG_HUGETLB_PAGE */
static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm,
@@ -527,7 +530,8 @@ static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm,
*/
if (is_vm_hugetlb_page(dst_vma))
return __mcopy_atomic_hugetlb(dst_mm, dst_vma, dst_start,
- src_start, len, zeropage);
+ src_start, len, zeropage,
+ wp_copy);
if (!vma_is_anonymous(dst_vma) && !vma_is_shmem(dst_vma))
goto out_unlock;
--
2.26.2
next prev parent reply other threads:[~2021-01-15 17:12 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-15 17:08 [PATCH RFC 00/30] userfaultfd-wp: Support shmem and hugetlbfs Peter Xu
2021-01-15 17:08 ` [PATCH RFC 01/30] mm/thp: Simplify copying of huge zero page pmd when fork Peter Xu
2021-01-15 17:08 ` [PATCH RFC 02/30] mm/userfaultfd: Fix uffd-wp special cases for fork() Peter Xu
2021-01-15 17:08 ` [PATCH RFC 03/30] mm/userfaultfd: Fix a few thp pmd missing uffd-wp bit Peter Xu
2021-01-15 17:08 ` [PATCH RFC 04/30] shmem/userfaultfd: Take care of UFFDIO_COPY_MODE_WP Peter Xu
2021-01-15 17:08 ` [PATCH RFC 05/30] mm: Clear vmf->pte after pte_unmap_same() returns Peter Xu
2021-01-15 17:08 ` [PATCH RFC 06/30] mm/userfaultfd: Introduce special pte for unmapped file-backed mem Peter Xu
2021-01-15 17:08 ` [PATCH RFC 07/30] mm/swap: Introduce the idea of special swap ptes Peter Xu
2021-01-18 19:40 ` Jason Gunthorpe
2021-01-19 14:24 ` Peter Xu
2021-01-15 17:08 ` [PATCH RFC 08/30] shmem/userfaultfd: Handle uffd-wp special pte in page fault handler Peter Xu
2021-01-15 17:08 ` [PATCH RFC 09/30] mm: Drop first_index/last_index in zap_details Peter Xu
2021-01-15 17:08 ` [PATCH RFC 10/30] mm: Introduce zap_details.zap_flags Peter Xu
2021-01-15 17:08 ` [PATCH RFC 11/30] mm: Introduce ZAP_FLAG_SKIP_SWAP Peter Xu
2021-01-15 17:08 ` [PATCH RFC 12/30] mm: Pass zap_flags into unmap_mapping_pages() Peter Xu
2021-01-15 17:08 ` [PATCH RFC 13/30] shmem/userfaultfd: Persist uffd-wp bit across zapping for file-backed Peter Xu
2021-01-15 17:08 ` [PATCH RFC 14/30] shmem/userfaultfd: Allow wr-protect none pte for file-backed mem Peter Xu
2021-01-15 17:08 ` [PATCH RFC 15/30] shmem/userfaultfd: Allows file-back mem to be uffd wr-protected on thps Peter Xu
2021-01-15 17:08 ` [PATCH RFC 16/30] shmem/userfaultfd: Handle the left-overed special swap ptes Peter Xu
2021-01-15 17:08 ` [PATCH RFC 17/30] shmem/userfaultfd: Pass over uffd-wp special swap pte when fork() Peter Xu
2021-01-15 17:08 ` [PATCH RFC 18/30] hugetlb/userfaultfd: Hook page faults for uffd write protection Peter Xu
2021-01-15 17:08 ` Peter Xu [this message]
2021-01-15 17:08 ` [PATCH RFC 20/30] hugetlb/userfaultfd: Handle UFFDIO_WRITEPROTECT Peter Xu
2021-01-15 17:08 ` [PATCH RFC 21/30] hugetlb: Pass vma into huge_pte_alloc() Peter Xu
2021-01-28 22:59 ` Axel Rasmussen
2021-01-29 22:31 ` Peter Xu
2021-01-30 8:08 ` Axel Rasmussen
2021-01-15 17:08 ` [PATCH RFC 22/30] hugetlb/userfaultfd: Forbid huge pmd sharing when uffd enabled Peter Xu
2021-01-15 17:09 ` [PATCH RFC 23/30] mm/hugetlb: Introduce huge version of special swap pte helpers Peter Xu
2021-01-15 17:09 ` [PATCH RFC 24/30] mm/hugetlb: Move flush_hugetlb_tlb_range() into hugetlb.h Peter Xu
2021-01-15 17:09 ` [PATCH RFC 25/30] hugetlb/userfaultfd: Unshare all pmds for hugetlbfs when register wp Peter Xu
2021-01-15 17:09 ` [PATCH RFC 26/30] hugetlb/userfaultfd: Handle uffd-wp special pte in hugetlb pf handler Peter Xu
2021-01-15 17:09 ` [PATCH RFC 27/30] hugetlb/userfaultfd: Allow wr-protect none ptes Peter Xu
2021-01-15 17:09 ` [PATCH RFC 28/30] hugetlb/userfaultfd: Only drop uffd-wp special pte if required Peter Xu
2021-01-15 17:09 ` [PATCH RFC 29/30] userfaultfd: Enable write protection for shmem & hugetlbfs Peter Xu
2021-01-15 17:12 ` [PATCH RFC 30/30] userfaultfd/selftests: Enable uffd-wp for shmem/hugetlbfs Peter Xu
2021-01-29 22:49 ` [PATCH RFC 00/30] userfaultfd-wp: Support shmem and hugetlbfs Peter Xu
2021-02-05 21:53 ` Mike Kravetz
2021-02-06 2:36 ` Peter Xu
2021-02-09 19:29 ` Mike Kravetz
2021-02-09 22:00 ` Peter Xu
2021-02-05 22:21 ` Hugh Dickins
2021-02-06 2:47 ` Peter Xu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210115170907.24498-20-peterx@redhat.com \
--to=peterx@redhat.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=axelrasmussen@google.com \
--cc=hughd@google.com \
--cc=jglisse@redhat.com \
--cc=kirill@shutemov.name \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mike.kravetz@oracle.com \
--cc=nadav.amit@gmail.com \
--cc=rppt@linux.vnet.ibm.com \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).