linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Xu <peterx@redhat.com>
To: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Cc: Brian Geffon <bgeffon@google.com>,
	Pavel Emelyanov <xemul@virtuozzo.com>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	David Hildenbrand <david@redhat.com>,
	peterx@redhat.com, Martin Cracauer <cracauer@cons.org>,
	Andrea Arcangeli <aarcange@redhat.com>,
	Mel Gorman <mgorman@suse.de>,
	Bobby Powers <bobbypowers@gmail.com>,
	Mike Rapoport <rppt@linux.vnet.ibm.com>,
	"Kirill A . Shutemov" <kirill@shutemov.name>,
	Maya Gokhale <gokhale2@llnl.gov>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Marty McFadden <mcfadden8@llnl.gov>,
	Denis Plotnikov <dplotnikov@virtuozzo.com>,
	Hugh Dickins <hughd@google.com>,
	"Dr . David Alan Gilbert" <dgilbert@redhat.com>,
	Jerome Glisse <jglisse@redhat.com>
Subject: [PATCH v6 06/19] mm: merge parameters for change_protection()
Date: Thu, 20 Feb 2020 11:30:59 -0500	[thread overview]
Message-ID: <20200220163112.11409-7-peterx@redhat.com> (raw)
In-Reply-To: <20200220163112.11409-1-peterx@redhat.com>

change_protection() was used by either the NUMA or mprotect() code,
there's one parameter for each of the callers (dirty_accountable and
prot_numa).  Further, these parameters are passed along the calls:

  - change_protection_range()
  - change_p4d_range()
  - change_pud_range()
  - change_pmd_range()
  - ...

Now we introduce a flag for change_protect() and all these helpers to
replace these parameters.  Then we can avoid passing multiple parameters
multiple times along the way.

More importantly, it'll greatly simplify the work if we want to
introduce any new parameters to change_protection().  In the follow up
patches, a new parameter for userfaultfd write protection will be
introduced.

No functional change at all.

Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 include/linux/huge_mm.h |  2 +-
 include/linux/mm.h      | 14 +++++++++++++-
 mm/huge_memory.c        |  3 ++-
 mm/mempolicy.c          |  2 +-
 mm/mprotect.c           | 29 ++++++++++++++++-------------
 5 files changed, 33 insertions(+), 17 deletions(-)

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 5aca3d1bdb32..92220ec66862 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -46,7 +46,7 @@ extern bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
 			 pmd_t *old_pmd, pmd_t *new_pmd);
 extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
 			unsigned long addr, pgprot_t newprot,
-			int prot_numa);
+			unsigned long cp_flags);
 vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write);
 vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write);
 enum transparent_hugepage_flag {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 51a886d50758..547c7415ff92 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1660,9 +1660,21 @@ extern unsigned long move_page_tables(struct vm_area_struct *vma,
 		unsigned long old_addr, struct vm_area_struct *new_vma,
 		unsigned long new_addr, unsigned long len,
 		bool need_rmap_locks);
+
+/*
+ * Flags used by change_protection().  For now we make it a bitmap so
+ * that we can pass in multiple flags just like parameters.  However
+ * for now all the callers are only use one of the flags at the same
+ * time.
+ */
+/* Whether we should allow dirty bit accounting */
+#define  MM_CP_DIRTY_ACCT                  (1UL << 0)
+/* Whether this protection change is for NUMA hints */
+#define  MM_CP_PROT_NUMA                   (1UL << 1)
+
 extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
 			      unsigned long end, pgprot_t newprot,
-			      int dirty_accountable, int prot_numa);
+			      unsigned long cp_flags);
 extern int mprotect_fixup(struct vm_area_struct *vma,
 			  struct vm_area_struct **pprev, unsigned long start,
 			  unsigned long end, unsigned long newflags);
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b08b199f9a11..2b01765bee92 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1934,13 +1934,14 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr,
  *  - HPAGE_PMD_NR is protections changed and TLB flush necessary
  */
 int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,
-		unsigned long addr, pgprot_t newprot, int prot_numa)
+		unsigned long addr, pgprot_t newprot, unsigned long cp_flags)
 {
 	struct mm_struct *mm = vma->vm_mm;
 	spinlock_t *ptl;
 	pmd_t entry;
 	bool preserve_write;
 	int ret;
+	bool prot_numa = cp_flags & MM_CP_PROT_NUMA;
 
 	ptl = __pmd_trans_huge_lock(pmd, vma);
 	if (!ptl)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 977c641f78cf..2ea6c4c0579a 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -598,7 +598,7 @@ unsigned long change_prot_numa(struct vm_area_struct *vma,
 {
 	int nr_updated;
 
-	nr_updated = change_protection(vma, addr, end, PAGE_NONE, 0, 1);
+	nr_updated = change_protection(vma, addr, end, PAGE_NONE, MM_CP_PROT_NUMA);
 	if (nr_updated)
 		count_vm_numa_events(NUMA_PTE_UPDATES, nr_updated);
 
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 7a8e84f86831..1565058ebcfc 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -37,12 +37,14 @@
 
 static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
 		unsigned long addr, unsigned long end, pgprot_t newprot,
-		int dirty_accountable, int prot_numa)
+		unsigned long cp_flags)
 {
 	pte_t *pte, oldpte;
 	spinlock_t *ptl;
 	unsigned long pages = 0;
 	int target_node = NUMA_NO_NODE;
+	bool dirty_accountable = cp_flags & MM_CP_DIRTY_ACCT;
+	bool prot_numa = cp_flags & MM_CP_PROT_NUMA;
 
 	/*
 	 * Can be called with only the mmap_sem for reading by
@@ -163,7 +165,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
 
 static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
 		pud_t *pud, unsigned long addr, unsigned long end,
-		pgprot_t newprot, int dirty_accountable, int prot_numa)
+		pgprot_t newprot, unsigned long cp_flags)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -195,7 +197,7 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
 				__split_huge_pmd(vma, pmd, addr, false, NULL);
 			} else {
 				int nr_ptes = change_huge_pmd(vma, pmd, addr,
-						newprot, prot_numa);
+							      newprot, cp_flags);
 
 				if (nr_ptes) {
 					if (nr_ptes == HPAGE_PMD_NR) {
@@ -210,7 +212,7 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
 			/* fall through, the trans huge pmd just split */
 		}
 		this_pages = change_pte_range(vma, pmd, addr, next, newprot,
-				 dirty_accountable, prot_numa);
+					      cp_flags);
 		pages += this_pages;
 next:
 		cond_resched();
@@ -226,7 +228,7 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
 
 static inline unsigned long change_pud_range(struct vm_area_struct *vma,
 		p4d_t *p4d, unsigned long addr, unsigned long end,
-		pgprot_t newprot, int dirty_accountable, int prot_numa)
+		pgprot_t newprot, unsigned long cp_flags)
 {
 	pud_t *pud;
 	unsigned long next;
@@ -238,7 +240,7 @@ static inline unsigned long change_pud_range(struct vm_area_struct *vma,
 		if (pud_none_or_clear_bad(pud))
 			continue;
 		pages += change_pmd_range(vma, pud, addr, next, newprot,
-				 dirty_accountable, prot_numa);
+					  cp_flags);
 	} while (pud++, addr = next, addr != end);
 
 	return pages;
@@ -246,7 +248,7 @@ static inline unsigned long change_pud_range(struct vm_area_struct *vma,
 
 static inline unsigned long change_p4d_range(struct vm_area_struct *vma,
 		pgd_t *pgd, unsigned long addr, unsigned long end,
-		pgprot_t newprot, int dirty_accountable, int prot_numa)
+		pgprot_t newprot, unsigned long cp_flags)
 {
 	p4d_t *p4d;
 	unsigned long next;
@@ -258,7 +260,7 @@ static inline unsigned long change_p4d_range(struct vm_area_struct *vma,
 		if (p4d_none_or_clear_bad(p4d))
 			continue;
 		pages += change_pud_range(vma, p4d, addr, next, newprot,
-				 dirty_accountable, prot_numa);
+					  cp_flags);
 	} while (p4d++, addr = next, addr != end);
 
 	return pages;
@@ -266,7 +268,7 @@ static inline unsigned long change_p4d_range(struct vm_area_struct *vma,
 
 static unsigned long change_protection_range(struct vm_area_struct *vma,
 		unsigned long addr, unsigned long end, pgprot_t newprot,
-		int dirty_accountable, int prot_numa)
+		unsigned long cp_flags)
 {
 	struct mm_struct *mm = vma->vm_mm;
 	pgd_t *pgd;
@@ -283,7 +285,7 @@ static unsigned long change_protection_range(struct vm_area_struct *vma,
 		if (pgd_none_or_clear_bad(pgd))
 			continue;
 		pages += change_p4d_range(vma, pgd, addr, next, newprot,
-				 dirty_accountable, prot_numa);
+					  cp_flags);
 	} while (pgd++, addr = next, addr != end);
 
 	/* Only flush the TLB if we actually modified any entries: */
@@ -296,14 +298,15 @@ static unsigned long change_protection_range(struct vm_area_struct *vma,
 
 unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
 		       unsigned long end, pgprot_t newprot,
-		       int dirty_accountable, int prot_numa)
+		       unsigned long cp_flags)
 {
 	unsigned long pages;
 
 	if (is_vm_hugetlb_page(vma))
 		pages = hugetlb_change_protection(vma, start, end, newprot);
 	else
-		pages = change_protection_range(vma, start, end, newprot, dirty_accountable, prot_numa);
+		pages = change_protection_range(vma, start, end, newprot,
+						cp_flags);
 
 	return pages;
 }
@@ -425,7 +428,7 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev,
 	vma_set_page_prot(vma);
 
 	change_protection(vma, start, end, vma->vm_page_prot,
-			  dirty_accountable, 0);
+			  dirty_accountable ? MM_CP_DIRTY_ACCT : 0);
 
 	/*
 	 * Private VM_LOCKED VMA becoming writable: trigger COW to avoid major
-- 
2.24.1


  parent reply	other threads:[~2020-02-20 16:31 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-20 16:30 [PATCH v6 00/19] userfaultfd: write protection support Peter Xu
2020-02-20 16:30 ` [PATCH v6 01/19] userfaultfd: wp: add helper for writeprotect check Peter Xu
2020-02-20 16:30 ` [PATCH v6 02/19] userfaultfd: wp: hook userfault handler to write protection fault Peter Xu
2020-02-20 16:30 ` [PATCH v6 03/19] userfaultfd: wp: add WP pagetable tracking to x86 Peter Xu
2020-02-20 16:30 ` [PATCH v6 04/19] userfaultfd: wp: userfaultfd_pte/huge_pmd_wp() helpers Peter Xu
2020-02-20 16:30 ` [PATCH v6 05/19] userfaultfd: wp: add UFFDIO_COPY_MODE_WP Peter Xu
2020-02-20 16:30 ` Peter Xu [this message]
2020-02-20 16:31 ` [PATCH v6 07/19] userfaultfd: wp: apply _PAGE_UFFD_WP bit Peter Xu
2020-02-20 16:31 ` [PATCH v6 08/19] userfaultfd: wp: drop _PAGE_UFFD_WP properly when fork Peter Xu
2020-02-20 16:31 ` [PATCH v6 09/19] userfaultfd: wp: add pmd_swp_*uffd_wp() helpers Peter Xu
2020-02-20 16:31 ` [PATCH v6 10/19] userfaultfd: wp: support swap and page migration Peter Xu
2020-02-20 16:31 ` [PATCH v6 11/19] khugepaged: skip collapse if uffd-wp detected Peter Xu
2020-02-20 16:31 ` [PATCH v6 12/19] userfaultfd: wp: support write protection for userfault vma range Peter Xu
2020-02-20 16:31 ` [PATCH v6 13/19] userfaultfd: wp: add the writeprotect API to userfaultfd ioctl Peter Xu
2020-02-20 16:31 ` [PATCH v6 14/19] userfaultfd: wp: enabled write protection in userfaultfd API Peter Xu
2020-02-20 16:31 ` [PATCH v6 15/19] userfaultfd: wp: don't wake up when doing write protect Peter Xu
2020-02-20 16:31 ` [PATCH v6 16/19] userfaultfd: wp: UFFDIO_REGISTER_MODE_WP documentation update Peter Xu
2020-02-20 16:31 ` [PATCH v6 17/19] userfaultfd: wp: declare _UFFDIO_WRITEPROTECT conditionally Peter Xu
2020-02-20 16:31 ` [PATCH v6 18/19] userfaultfd: selftests: refactor statistics Peter Xu
2020-02-20 16:31 ` [PATCH v6 19/19] userfaultfd: selftests: add write-protect test 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=20200220163112.11409-7-peterx@redhat.com \
    --to=peterx@redhat.com \
    --cc=aarcange@redhat.com \
    --cc=bgeffon@google.com \
    --cc=bobbypowers@gmail.com \
    --cc=cracauer@cons.org \
    --cc=david@redhat.com \
    --cc=dgilbert@redhat.com \
    --cc=dplotnikov@virtuozzo.com \
    --cc=gokhale2@llnl.gov \
    --cc=hannes@cmpxchg.org \
    --cc=hughd@google.com \
    --cc=jglisse@redhat.com \
    --cc=kirill@shutemov.name \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mcfadden8@llnl.gov \
    --cc=mgorman@suse.de \
    --cc=mike.kravetz@oracle.com \
    --cc=rppt@linux.vnet.ibm.com \
    --cc=xemul@virtuozzo.com \
    /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).