@@ -1924,66 +1924,68 @@ static long __get_user_pages_remote(struct mm_struct *mm,
* Or NULL if the caller does not require them.
*
* This is the same as get_user_pages_remote(), just with a less-flexible
* calling convention where we assume that the mm being operated on belongs to
* the current task, and doesn't allow passing of a locked parameter. We also
* obviously don't pass FOLL_REMOTE in here.
*/
long get_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas)
{
if (!is_valid_gup_flags(gup_flags))
return -EINVAL;
return __gup_longterm_locked(current->mm, start, nr_pages,
pages, vmas, gup_flags | FOLL_TOUCH);
}
EXPORT_SYMBOL(get_user_pages);
/**
- * get_user_pages_locked() is suitable to replace the form:
+ * get_user_pages_locked() - variant of get_user_pages()
+ *
+ * @start: starting user address
+ * @nr_pages: number of pages from start to pin
+ * @gup_flags: flags modifying lookup behaviour
+ * @pages: array that receives pointers to the pages pinned.
+ * Should be at least nr_pages long. Or NULL, if caller
+ * only intends to ensure the pages are faulted in.
+ * @locked: pointer to lock flag indicating whether lock is held and
+ * subsequently whether VM_FAULT_RETRY functionality can be
+ * utilised. Lock must initially be held.
+ *
+ * It is suitable to replace the form:
*
* mmap_read_lock(mm);
* do_something()
* get_user_pages(mm, ..., pages, NULL);
* mmap_read_unlock(mm);
*
* to:
*
* int locked = 1;
* mmap_read_lock(mm);
* do_something()
* get_user_pages_locked(mm, ..., pages, &locked);
* if (locked)
* mmap_read_unlock(mm);
*
- * @start: starting user address
- * @nr_pages: number of pages from start to pin
- * @gup_flags: flags modifying lookup behaviour
- * @pages: array that receives pointers to the pages pinned.
- * Should be at least nr_pages long. Or NULL, if caller
- * only intends to ensure the pages are faulted in.
- * @locked: pointer to lock flag indicating whether lock is held and
- * subsequently whether VM_FAULT_RETRY functionality can be
- * utilised. Lock must initially be held.
- *
* We can leverage the VM_FAULT_RETRY functionality in the page fault
* paths better by using either get_user_pages_locked() or
* get_user_pages_unlocked().
*
*/
long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
int *locked)
{
/*
* FIXME: Current FOLL_LONGTERM behavior is incompatible with
* FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on
* vmas. As there are no users of this flag in this call we simply
* disallow this option for now.
*/
if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM))
return -EINVAL;
/*
* FOLL_PIN must only be set internally by the pin_user_pages*() APIs,
* never directly by the caller, so enforce that:
@@ -478,66 +478,66 @@ static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn)
static inline unsigned long *get_pageblock_bitmap(struct page *page,
unsigned long pfn)
{
#ifdef CONFIG_SPARSEMEM
return section_to_usemap(__pfn_to_section(pfn));
#else
return page_zone(page)->pageblock_flags;
#endif /* CONFIG_SPARSEMEM */
}
static inline int pfn_to_bitidx(struct page *page, unsigned long pfn)
{
#ifdef CONFIG_SPARSEMEM
pfn &= (PAGES_PER_SECTION-1);
#else
pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages);
#endif /* CONFIG_SPARSEMEM */
return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
}
-/**
- * get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages
- * @page: The page within the block of interest
- * @pfn: The target page frame number
- * @mask: mask of bits that the caller is interested in
- *
- * Return: pageblock_bits flags
- */
static __always_inline
unsigned long __get_pfnblock_flags_mask(struct page *page,
unsigned long pfn,
unsigned long mask)
{
unsigned long *bitmap;
unsigned long bitidx, word_bitidx;
unsigned long word;
bitmap = get_pageblock_bitmap(page, pfn);
bitidx = pfn_to_bitidx(page, pfn);
word_bitidx = bitidx / BITS_PER_LONG;
bitidx &= (BITS_PER_LONG-1);
word = bitmap[word_bitidx];
return (word >> bitidx) & mask;
}
+/**
+ * get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages
+ * @page: The page within the block of interest
+ * @pfn: The target page frame number
+ * @mask: mask of bits that the caller is interested in
+ *
+ * Return: pageblock_bits flags
+ */
unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn,
unsigned long mask)
{
return __get_pfnblock_flags_mask(page, pfn, mask);
}
static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn)
{
return __get_pfnblock_flags_mask(page, pfn, MIGRATETYPE_MASK);
}
/**
* set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages
* @page: The page within the block of interest
* @flags: The flags to set
* @pfn: The target page frame number
* @mask: mask of bits that the caller is interested in
*/
void set_pfnblock_flags_mask(struct page *page, unsigned long flags,
unsigned long pfn,
@@ -620,43 +620,49 @@ static unsigned long __invalidate_mapping_pages(struct address_space *mapping,
* @start: the offset 'from' which to invalidate
* @end: the offset 'to' which to invalidate (inclusive)
*
* This function only removes the unlocked pages, if you want to
* remove all the pages of one inode, you must call truncate_inode_pages.
*
* invalidate_mapping_pages() will not block on IO activity. It will not
* invalidate pages which are dirty, locked, under writeback or mapped into
* pagetables.
*
* Return: the number of the pages that were invalidated
*/
unsigned long invalidate_mapping_pages(struct address_space *mapping,
pgoff_t start, pgoff_t end)
{
return __invalidate_mapping_pages(mapping, start, end, NULL);
}
EXPORT_SYMBOL(invalidate_mapping_pages);
/**
- * This helper is similar with the above one, except that it accounts for pages
- * that are likely on a pagevec and count them in @nr_pagevec, which will used by
+ * invalidate_mapping_pagevec - This helper is similar to
+ * invalidate_mapping_pages(), except that it accounts for pages that are
+ * likely on a pagevec and count them in @nr_pagevec, which will be used by
* the caller.
+ *
+ * @mapping: the address_space which holds the pages to invalidate
+ * @start: the offset 'from' which to invalidate
+ * @end: the offset 'to' which to invalidate (inclusive)
+ *
*/
void invalidate_mapping_pagevec(struct address_space *mapping,
pgoff_t start, pgoff_t end, unsigned long *nr_pagevec)
{
__invalidate_mapping_pages(mapping, start, end, nr_pagevec);
}
/*
* This is like invalidate_complete_page(), except it ignores the page's
* refcount. We do this because invalidate_inode_pages2() needs stronger
* invalidation guarantees, and cannot afford to leave pages behind because
* shrink_page_list() has a temp ref on them, or because they're transiently
* sitting in the lru_cache_add() pagevecs.
*/
static int
invalidate_complete_page2(struct address_space *mapping, struct page *page)
{
unsigned long flags;
if (page->mapping != mapping)
Kernel-doc markups should use this format: identifier - description Fix some issues on mm files: 1) The definition for get_user_pages_locked() doesn't follow it. Also, it expects a short descrpition at the header, followed by a long one, after the parameters. Fix it. 2) Kernel-doc requires that a kernel-doc markup to be immediatly below the function prototype, as otherwise it will rename it. So, move get_pfnblock_flags_mask() description to the right place. 3) Make invalidate_mapping_pagevec() to also follow the expected kernel-doc format. While here, fix a few minor English syntax issues, as suggested by Matthew: will used -> will be used similar with -> similar to Suggested-by: Mattew Wilcox <willy@infradead.org> # English fixes Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> --- mm/gup.c | 24 +++++++++++++----------- mm/page_alloc.c | 16 ++++++++-------- mm/truncate.c | 10 ++++++++-- 3 files changed, 29 insertions(+), 21 deletions(-)