The patch titled
mm: FOLL flags for GUP flags
has been added to the -mm tree. Its filename is
mm-foll-flags-for-gup-flags.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: mm: FOLL flags for GUP flags
From: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>
__get_user_pages() has been taking its own GUP flags, then processing
them into FOLL flags for follow_page(). Though oddly named, the FOLL
flags are more widely used, so pass them to __get_user_pages() now.
Sorry, VM flags, VM_FAULT flags and FAULT_FLAGs are still distinct.
(The patch to __get_user_pages() looks peculiar, with both gup_flags
and foll_flags: the gup_flags remain constant; but as before there's
an exceptional case, out of scope of the patch, in which foll_flags
per page have FOLL_WRITE masked off.)
Signed-off-by: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Nick Piggin <npiggin@xxxxxxx>
Cc: Mel Gorman <mel@xxxxxxxxx>
Cc: Minchan Kim <minchan.kim@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 1
mm/internal.h | 6 -----
mm/memory.c | 44 ++++++++++++++++++-------------------------
mm/mlock.c | 4 +--
mm/nommu.c | 16 +++++++--------
5 files changed, 31 insertions(+), 40 deletions(-)
diff -puN include/linux/mm.h~mm-foll-flags-for-gup-flags include/linux/mm.h
--- a/include/linux/mm.h~mm-foll-flags-for-gup-flags
+++ a/include/linux/mm.h
@@ -1239,6 +1239,7 @@ struct page *follow_page(struct vm_area_
#define FOLL_TOUCH 0x02 /* mark page accessed */
#define FOLL_GET 0x04 /* do get_page on page */
#define FOLL_DUMP 0x08 /* give error on hole if it would be zero */
+#define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */
typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
void *data);
diff -puN mm/internal.h~mm-foll-flags-for-gup-flags mm/internal.h
--- a/mm/internal.h~mm-foll-flags-for-gup-flags
+++ a/mm/internal.h
@@ -250,12 +250,8 @@ static inline void mminit_validate_memmo
}
#endif /* CONFIG_SPARSEMEM */
-#define GUP_FLAGS_WRITE 0x01
-#define GUP_FLAGS_FORCE 0x02
-#define GUP_FLAGS_DUMP 0x04
-
int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int len, int flags,
+ unsigned long start, int len, unsigned int foll_flags,
struct page **pages, struct vm_area_struct **vmas);
#define ZONE_RECLAIM_NOSCAN -2
diff -puN mm/memory.c~mm-foll-flags-for-gup-flags mm/memory.c
--- a/mm/memory.c~mm-foll-flags-for-gup-flags
+++ a/mm/memory.c
@@ -1209,27 +1209,29 @@ no_page_table:
}
int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int nr_pages, int flags,
+ unsigned long start, int nr_pages, unsigned int gup_flags,
struct page **pages, struct vm_area_struct **vmas)
{
int i;
- unsigned int vm_flags = 0;
- int write = !!(flags & GUP_FLAGS_WRITE);
- int force = !!(flags & GUP_FLAGS_FORCE);
+ unsigned long vm_flags;
if (nr_pages <= 0)
return 0;
+
+ VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET));
+
/*
* Require read or write permissions.
- * If 'force' is set, we only require the "MAY" flags.
+ * If FOLL_FORCE is set, we only require the "MAY" flags.
*/
- vm_flags = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
- vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
+ vm_flags = (gup_flags & FOLL_WRITE) ?
+ (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
+ vm_flags &= (gup_flags & FOLL_FORCE) ?
+ (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
i = 0;
do {
struct vm_area_struct *vma;
- unsigned int foll_flags;
vma = find_extend_vma(mm, start);
if (!vma && in_gate_area(tsk, start)) {
@@ -1241,7 +1243,7 @@ int __get_user_pages(struct task_struct
pte_t *pte;
/* user gate pages are read-only */
- if (write)
+ if (gup_flags & FOLL_WRITE)
return i ? : -EFAULT;
if (pg > TASK_SIZE)
pgd = pgd_offset_k(pg);
@@ -1278,22 +1280,15 @@ int __get_user_pages(struct task_struct
!(vm_flags & vma->vm_flags))
return i ? : -EFAULT;
- foll_flags = FOLL_TOUCH;
- if (pages)
- foll_flags |= FOLL_GET;
- if (flags & GUP_FLAGS_DUMP)
- foll_flags |= FOLL_DUMP;
- if (write)
- foll_flags |= FOLL_WRITE;
-
if (is_vm_hugetlb_page(vma)) {
i = follow_hugetlb_page(mm, vma, pages, vmas,
- &start, &nr_pages, i, foll_flags);
+ &start, &nr_pages, i, gup_flags);
continue;
}
do {
struct page *page;
+ unsigned int foll_flags = gup_flags;
/*
* If we have a pending SIGKILL, don't keep faulting
@@ -1302,9 +1297,6 @@ int __get_user_pages(struct task_struct
if (unlikely(fatal_signal_pending(current)))
return i ? i : -ERESTARTSYS;
- if (write)
- foll_flags |= FOLL_WRITE;
-
cond_resched();
while (!(page = follow_page(vma, start, foll_flags))) {
int ret;
@@ -1416,12 +1408,14 @@ int get_user_pages(struct task_struct *t
unsigned long start, int nr_pages, int write, int force,
struct page **pages, struct vm_area_struct **vmas)
{
- int flags = 0;
+ int flags = FOLL_TOUCH;
+ if (pages)
+ flags |= FOLL_GET;
if (write)
- flags |= GUP_FLAGS_WRITE;
+ flags |= FOLL_WRITE;
if (force)
- flags |= GUP_FLAGS_FORCE;
+ flags |= FOLL_FORCE;
return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas);
}
@@ -1448,7 +1442,7 @@ struct page *get_dump_page(unsigned long
struct page *page;
if (__get_user_pages(current, current->mm, addr, 1,
- GUP_FLAGS_FORCE | GUP_FLAGS_DUMP, &page, &vma) < 1)
+ FOLL_FORCE | FOLL_DUMP | FOLL_GET, &page, &vma) < 1)
return NULL;
if (page == ZERO_PAGE(0)) {
page_cache_release(page);
diff -puN mm/mlock.c~mm-foll-flags-for-gup-flags mm/mlock.c
--- a/mm/mlock.c~mm-foll-flags-for-gup-flags
+++ a/mm/mlock.c
@@ -166,9 +166,9 @@ static long __mlock_vma_pages_range(stru
VM_BUG_ON(end > vma->vm_end);
VM_BUG_ON(!rwsem_is_locked(&mm->mmap_sem));
- gup_flags = 0;
+ gup_flags = FOLL_TOUCH | FOLL_GET;
if (vma->vm_flags & VM_WRITE)
- gup_flags = GUP_FLAGS_WRITE;
+ gup_flags |= FOLL_WRITE;
while (nr_pages > 0) {
int i;
diff -puN mm/nommu.c~mm-foll-flags-for-gup-flags mm/nommu.c
--- a/mm/nommu.c~mm-foll-flags-for-gup-flags
+++ a/mm/nommu.c
@@ -128,20 +128,20 @@ unsigned int kobjsize(const void *objp)
}
int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int nr_pages, int flags,
+ unsigned long start, int nr_pages, int foll_flags,
struct page **pages, struct vm_area_struct **vmas)
{
struct vm_area_struct *vma;
unsigned long vm_flags;
int i;
- int write = !!(flags & GUP_FLAGS_WRITE);
- int force = !!(flags & GUP_FLAGS_FORCE);
/* calculate required read or write permissions.
- * - if 'force' is set, we only require the "MAY" flags.
+ * If FOLL_FORCE is set, we only require the "MAY" flags.
*/
- vm_flags = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
- vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
+ vm_flags = (foll_flags & FOLL_WRITE) ?
+ (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
+ vm_flags &= (foll_flags & FOLL_FORCE) ?
+ (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
for (i = 0; i < nr_pages; i++) {
vma = find_vma(mm, start);
@@ -183,9 +183,9 @@ int get_user_pages(struct task_struct *t
int flags = 0;
if (write)
- flags |= GUP_FLAGS_WRITE;
+ flags |= FOLL_WRITE;
if (force)
- flags |= GUP_FLAGS_FORCE;
+ flags |= FOLL_FORCE;
return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas);
}
_
Patches currently in -mm which might be from hugh.dickins@xxxxxxxxxxxxx are
linux-next.patch
acpi-fix-null-bug-for-hid-uid-string-2.patch
vfs-optimize-touch_time-too-fix.patch
fs-new-truncate-helpers.patch
fs-use-new-truncate-helpers.patch
fs-introduce-new-truncate-sequence.patch
fs-convert-simple-fs-to-new-truncate.patch
tmpfs-convert-to-use-the-new-truncate-convention.patch
ext2-convert-to-use-the-new-truncate-convention.patch
fat-convert-to-use-the-new-truncate-convention.patch
btrfs-convert-to-use-the-new-truncate-convention.patch
jfs-convert-to-use-the-new-truncate-convention.patch
udf-convert-to-use-the-new-truncate-convention.patch
minix-convert-to-use-the-new-truncate-convention.patch
vfs-seq_file-add-helpers-for-data-filling.patch
vfs-revert-proc-mounts-to-old-behavior-for-unreachable-mountpoints.patch
vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps.patch
mm-oom-analysis-add-shmem-vmstat.patch
ksm-add-mmu_notifier-set_pte_at_notify.patch
ksm-first-tidy-up-madvise_vma.patch
ksm-define-madv_mergeable-and-madv_unmergeable.patch
ksm-the-mm-interface-to-ksm.patch
ksm-no-debug-in-page_dup_rmap.patch
ksm-identify-pageksm-pages.patch
ksm-kernel-samepage-merging.patch
ksm-prevent-mremap-move-poisoning.patch
ksm-change-copyright-message.patch
ksm-change-ksm-nice-level-to-be-5.patch
ksm-rename-kernel_pages_allocated.patch
ksm-move-pages_sharing-updates.patch
ksm-pages_unshared-and-pages_volatile.patch
ksm-break-cow-once-unshared.patch
ksm-keep-quiet-while-list-empty.patch
ksm-five-little-cleanups.patch
ksm-fix-endless-loop-on-oom.patch
ksm-distribute-remove_mm_from_lists.patch
ksm-fix-oom-deadlock.patch
ksm-fix-deadlock-with-munlock-in-exit_mmap.patch
ksm-sysfs-and-defaults.patch
ksm-add-some-documentation.patch
ksm-remove-vm_mergeable_flags.patch
ksm-clean-up-obsolete-references.patch
ksm-unmerge-is-an-origin-of-ooms.patch
ksm-mremap-use-err-from-ksm_madvise.patch
mm-add_to_swap_cache-must-not-sleep.patch
mm-add_to_swap_cache-does-not-return-eexist.patch
mm-includecheck-fix-for-mm-shmemc.patch
mm-introduce-page_lru_base_type-fix.patch
mm-replace-various-uses-of-num_physpages-by-totalram_pages.patch
hugetlbfs-allow-the-creation-of-files-suitable-for-map_private-on-the-vfs-internal-mount.patch
hugetlb-add-map_hugetlb-for-mmaping-pseudo-anonymous-huge-page-regions.patch
hugetlb-add-map_hugetlb-example.patch
mm-munlock-use-follow_page.patch
mm-remove-unused-gup-flags.patch
mm-add-get_dump_page.patch
mm-foll_dump-replace-foll_anon.patch
mm-follow_hugetlb_page-flags.patch
mm-fix-anonymous-dirtying.patch
mm-reinstate-zero_page.patch
mm-foll-flags-for-gup-flags.patch
getrusage-fill-ru_maxrss-value.patch
getrusage-fill-ru_maxrss-value-update.patch
ramfs-move-ramfs_magic-to-include-linux-magich.patch
memory-controller-soft-limit-organize-cgroups-v9-fix.patch
prio_tree-debugging-patch.patch
--
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