spin_unlock(&eb->refs_lock);
}
-static void mark_extent_buffer_accessed(struct extent_buffer *eb)
+static void mark_extent_buffer_accessed(struct extent_buffer *eb,
+ struct page *accessed)
{
unsigned long num_pages, i;
num_pages = num_extent_pages(eb->start, eb->len);
for (i = 0; i < num_pages; i++) {
struct page *p = extent_buffer_page(eb, i);
- mark_page_accessed(p);
+ if (p != accessed)
+ mark_page_accessed(p);
}
}
start >> PAGE_CACHE_SHIFT);
if (eb && atomic_inc_not_zero(&eb->refs)) {
rcu_read_unlock();
- mark_extent_buffer_accessed(eb);
+ mark_extent_buffer_accessed(eb, NULL);
return eb;
}
rcu_read_unlock();
spin_unlock(&mapping->private_lock);
unlock_page(p);
page_cache_release(p);
- mark_extent_buffer_accessed(exists);
+ mark_extent_buffer_accessed(exists, p);
goto free_eb;
}
attach_extent_buffer_page(eb, p);
spin_unlock(&mapping->private_lock);
WARN_ON(PageDirty(p));
- mark_page_accessed(p);
eb->pages[i] = p;
if (!PageUptodate(p))
uptodate = 0;
for (i = 0; i < num_pages; i++) {
/* page checked is some magic around finding pages that
* have been modified without going through btrfs_set_page_dirty
- * clear it here
+ * clear it here. There should be no need to mark the pages
+ * accessed as prepare_pages should have marked them accessed
+ * in prepare_pages via find_or_create_page()
*/
ClearPageChecked(pages[i]);
unlock_page(pages[i]);
- mark_page_accessed(pages[i]);
page_cache_release(pages[i]);
}
}
int all_mapped = 1;
index = block >> (PAGE_CACHE_SHIFT - bd_inode->i_blkbits);
- page = find_get_page(bd_mapping, index);
+ page = find_get_page_flags(bd_mapping, index, FGP_ACCESSED);
if (!page)
goto out;
struct buffer_head *bh = lookup_bh_lru(bdev, block, size);
if (bh == NULL) {
+ /* __find_get_block_slow will mark the page accessed */
bh = __find_get_block_slow(bdev, block);
if (bh)
bh_lru_install(bh);
- }
- if (bh)
+ } else
touch_buffer(bh);
+
return bh;
}
EXPORT_SYMBOL(__find_get_block);
* allocating. If we are looking at the buddy cache we would
* have taken a reference using ext4_mb_load_buddy and that
* would have pinned buddy page to page cache.
+ * The call to ext4_mb_get_buddy_page_lock will mark the
+ * page accessed.
*/
ret = ext4_mb_get_buddy_page_lock(sb, group, &e4b);
if (ret || !EXT4_MB_GRP_NEED_INIT(this_grp)) {
ret = -EIO;
goto err;
}
- mark_page_accessed(page);
if (e4b.bd_buddy_page == NULL) {
/*
ret = -EIO;
goto err;
}
- mark_page_accessed(page);
err:
ext4_mb_put_buddy_page_lock(&e4b);
return ret;
/* we could use find_or_create_page(), but it locks page
* what we'd like to avoid in fast path ... */
- page = find_get_page(inode->i_mapping, pnum);
+ page = find_get_page_flags(inode->i_mapping, pnum, FGP_ACCESSED);
if (page == NULL || !PageUptodate(page)) {
if (page)
/*
ret = -EIO;
goto err;
}
+
+ /* Pages marked accessed already */
e4b->bd_bitmap_page = page;
e4b->bd_bitmap = page_address(page) + (poff * sb->s_blocksize);
- mark_page_accessed(page);
block++;
pnum = block / blocks_per_page;
poff = block % blocks_per_page;
- page = find_get_page(inode->i_mapping, pnum);
+ page = find_get_page_flags(inode->i_mapping, pnum, FGP_ACCESSED);
if (page == NULL || !PageUptodate(page)) {
if (page)
page_cache_release(page);
ret = -EIO;
goto err;
}
+
+ /* Pages marked accessed already */
e4b->bd_buddy_page = page;
e4b->bd_buddy = page_address(page) + (poff * sb->s_blocksize);
- mark_page_accessed(page);
BUG_ON(e4b->bd_bitmap_page == NULL);
BUG_ON(e4b->bd_buddy_page == NULL);
goto repeat;
}
out:
- mark_page_accessed(page);
return page;
}
if (!page)
continue;
if (PageUptodate(page)) {
- mark_page_accessed(page);
f2fs_put_page(page, 1);
continue;
}
f2fs_submit_page_mbio(sbi, page, blk_addr, &fio);
- mark_page_accessed(page);
f2fs_put_page(page, 0);
}
out:
goto repeat;
}
got_it:
- mark_page_accessed(page);
return page;
}
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
- mark_page_accessed(page);
return page;
}
tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes);
flush_dcache_page(page);
- mark_page_accessed(page);
-
if (!tmp) {
unlock_page(page);
page_cache_release(page);
p = kmap_atomic(page);
memcpy(buf + copied, p + offset, amt);
kunmap_atomic(p);
- mark_page_accessed(page);
page_cache_release(page);
copied += amt;
index++;
yield();
}
} else {
- page = find_lock_page(mapping, index);
+ page = find_get_page_flags(mapping, index,
+ FGP_LOCK|FGP_ACCESSED);
if (!page)
return NULL;
}
map_bh(bh, sdp->sd_vfs, blkno);
unlock_page(page);
- mark_page_accessed(page);
page_cache_release(page);
return bh;
if (page) {
set_page_dirty(page);
unlock_page(page);
- mark_page_accessed(page);
page_cache_release(page);
}
ntfs_debug("Done.");
}
do {
unlock_page(pages[--do_pages]);
- mark_page_accessed(pages[do_pages]);
page_cache_release(pages[do_pages]);
} while (do_pages);
if (unlikely(status))
TESTPAGEFLAG(Locked, locked)
PAGEFLAG(Error, error) TESTCLEARFLAG(Error, error)
PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(Referenced, referenced)
+ __SETPAGEFLAG(Referenced, referenced)
PAGEFLAG(Dirty, dirty) TESTSCFLAG(Dirty, dirty) __CLEARPAGEFLAG(Dirty, dirty)
PAGEFLAG(LRU, lru) __CLEARPAGEFLAG(LRU, lru)
PAGEFLAG(Active, active) __CLEARPAGEFLAG(Active, active)
pgoff_t page_cache_prev_hole(struct address_space *mapping,
pgoff_t index, unsigned long max_scan);
+#define FGP_ACCESSED 0x00000001
+#define FGP_LOCK 0x00000002
+#define FGP_CREAT 0x00000004
+#define FGP_WRITE 0x00000008
+#define FGP_NOFS 0x00000010
+#define FGP_NOWAIT 0x00000020
+
+struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset,
+ int fgp_flags, gfp_t cache_gfp_mask, gfp_t radix_gfp_mask);
+
+/**
+ * find_get_page - find and get a page reference
+ * @mapping: the address_space to search
+ * @offset: the page index
+ *
+ * Looks up the page cache slot at @mapping & @offset. If there is a
+ * page cache page, it is returned with an increased refcount.
+ *
+ * Otherwise, %NULL is returned.
+ */
+static inline struct page *find_get_page(struct address_space *mapping,
+ pgoff_t offset)
+{
+ return pagecache_get_page(mapping, offset, 0, 0, 0);
+}
+
+static inline struct page *find_get_page_flags(struct address_space *mapping,
+ pgoff_t offset, int fgp_flags)
+{
+ return pagecache_get_page(mapping, offset, fgp_flags, 0, 0);
+}
+
+/**
+ * find_lock_page - locate, pin and lock a pagecache page
+ * pagecache_get_page - find and get a page reference
+ * @mapping: the address_space to search
+ * @offset: the page index
+ *
+ * Looks up the page cache slot at @mapping & @offset. If there is a
+ * page cache page, it is returned locked and with an increased
+ * refcount.
+ *
+ * Otherwise, %NULL is returned.
+ *
+ * find_lock_page() may sleep.
+ */
+static inline struct page *find_lock_page(struct address_space *mapping,
+ pgoff_t offset)
+{
+ return pagecache_get_page(mapping, offset, FGP_LOCK, 0, 0);
+}
+
+/**
+ * find_or_create_page - locate or add a pagecache page
+ * @mapping: the page's address_space
+ * @index: the page's index into the mapping
+ * @gfp_mask: page allocation mode
+ *
+ * Looks up the page cache slot at @mapping & @offset. If there is a
+ * page cache page, it is returned locked and with an increased
+ * refcount.
+ *
+ * If the page is not present, a new page is allocated using @gfp_mask
+ * and added to the page cache and the VM's LRU list. The page is
+ * returned locked and with an increased refcount.
+ *
+ * On memory exhaustion, %NULL is returned.
+ *
+ * find_or_create_page() may sleep, even if @gfp_flags specifies an
+ * atomic allocation!
+ */
+static inline struct page *find_or_create_page(struct address_space *mapping,
+ pgoff_t offset, gfp_t gfp_mask)
+{
+ return pagecache_get_page(mapping, offset,
+ FGP_LOCK|FGP_ACCESSED|FGP_CREAT,
+ gfp_mask, gfp_mask & GFP_RECLAIM_MASK);
+}
+
+/**
+ * grab_cache_page_nowait - returns locked page at given index in given cache
+ * @mapping: target address_space
+ * @index: the page index
+ *
+ * Same as grab_cache_page(), but do not wait if the page is unavailable.
+ * This is intended for speculative data generators, where the data can
+ * be regenerated if the page couldn't be grabbed. This routine should
+ * be safe to call while holding the lock for another page.
+ *
+ * Clear __GFP_FS when allocating the page to avoid recursion into the fs
+ * and deadlock against the caller's locked page.
+ */
+static inline struct page *grab_cache_page_nowait(struct address_space *mapping,
+ pgoff_t index)
+{
+ return pagecache_get_page(mapping, index,
+ FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
+ mapping_gfp_mask(mapping),
+ GFP_NOFS);
+}
+
struct page *find_get_entry(struct address_space *mapping, pgoff_t offset);
-struct page *find_get_page(struct address_space *mapping, pgoff_t offset);
struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset);
-struct page *find_lock_page(struct address_space *mapping, pgoff_t offset);
-struct page *find_or_create_page(struct address_space *mapping, pgoff_t index,
- gfp_t gfp_mask);
unsigned find_get_entries(struct address_space *mapping, pgoff_t start,
unsigned int nr_entries, struct page **entries,
pgoff_t *indices);
return find_or_create_page(mapping, index, mapping_gfp_mask(mapping));
}
-extern struct page * grab_cache_page_nowait(struct address_space *mapping,
- pgoff_t index);
extern struct page * read_cache_page(struct address_space *mapping,
pgoff_t index, filler_t *filler, void *data);
extern struct page * read_cache_page_gfp(struct address_space *mapping,
struct lruvec *lruvec, struct list_head *head);
extern void activate_page(struct page *);
extern void mark_page_accessed(struct page *);
+extern void init_page_accessed(struct page *page);
extern void lru_add_drain(void);
extern void lru_add_drain_cpu(int cpu);
extern void lru_add_drain_all(void);
}
EXPORT_SYMBOL(find_get_entry);
-/**
- * find_get_page - find and get a page reference
- * @mapping: the address_space to search
- * @offset: the page index
- *
- * Looks up the page cache slot at @mapping & @offset. If there is a
- * page cache page, it is returned with an increased refcount.
- *
- * Otherwise, %NULL is returned.
- */
-struct page *find_get_page(struct address_space *mapping, pgoff_t offset)
-{
- struct page *page = find_get_entry(mapping, offset);
-
- if (radix_tree_exceptional_entry(page))
- page = NULL;
- return page;
-}
-EXPORT_SYMBOL(find_get_page);
-
/**
* find_lock_entry - locate, pin and lock a page cache entry
* @mapping: the address_space to search
EXPORT_SYMBOL(find_lock_entry);
/**
- * find_lock_page - locate, pin and lock a pagecache page
+ * pagecache_get_page - find and get a page reference
* @mapping: the address_space to search
* @offset: the page index
+ * @fgp_flags: PCG flags
+ * @gfp_mask: gfp mask to use if a page is to be allocated
*
- * Looks up the page cache slot at @mapping & @offset. If there is a
- * page cache page, it is returned locked and with an increased
- * refcount.
- *
- * Otherwise, %NULL is returned.
- *
- * find_lock_page() may sleep.
- */
-struct page *find_lock_page(struct address_space *mapping, pgoff_t offset)
-{
- struct page *page = find_lock_entry(mapping, offset);
-
- if (radix_tree_exceptional_entry(page))
- page = NULL;
- return page;
-}
-EXPORT_SYMBOL(find_lock_page);
-
-/**
- * find_or_create_page - locate or add a pagecache page
- * @mapping: the page's address_space
- * @index: the page's index into the mapping
- * @gfp_mask: page allocation mode
+ * Looks up the page cache slot at @mapping & @offset.
*
- * Looks up the page cache slot at @mapping & @offset. If there is a
- * page cache page, it is returned locked and with an increased
- * refcount.
+ * PCG flags modify how the page is returned
*
- * If the page is not present, a new page is allocated using @gfp_mask
- * and added to the page cache and the VM's LRU list. The page is
- * returned locked and with an increased refcount.
+ * FGP_ACCESSED: the page will be marked accessed
+ * FGP_LOCK: Page is return locked
+ * FGP_CREAT: If page is not present then a new page is allocated using
+ * @gfp_mask and added to the page cache and the VM's LRU
+ * list. The page is returned locked and with an increased
+ * refcount. Otherwise, %NULL is returned.
*
- * On memory exhaustion, %NULL is returned.
+ * If FGP_LOCK or FGP_CREAT are specified then the function may sleep even
+ * if the GFP flags specified for FGP_CREAT are atomic.
*
- * find_or_create_page() may sleep, even if @gfp_flags specifies an
- * atomic allocation!
+ * If there is a page cache page, it is returned with an increased refcount.
*/
-struct page *find_or_create_page(struct address_space *mapping,
- pgoff_t index, gfp_t gfp_mask)
+struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset,
+ int fgp_flags, gfp_t cache_gfp_mask, gfp_t radix_gfp_mask)
{
struct page *page;
- int err;
+
repeat:
- page = find_lock_page(mapping, index);
- if (!page) {
- page = __page_cache_alloc(gfp_mask);
+ page = find_get_entry(mapping, offset);
+ if (radix_tree_exceptional_entry(page))
+ page = NULL;
+ if (!page)
+ goto no_page;
+
+ if (fgp_flags & FGP_LOCK) {
+ if (fgp_flags & FGP_NOWAIT) {
+ if (!trylock_page(page)) {
+ page_cache_release(page);
+ return NULL;
+ }
+ } else {
+ lock_page(page);
+ }
+
+ /* Has the page been truncated? */
+ if (unlikely(page->mapping != mapping)) {
+ unlock_page(page);
+ page_cache_release(page);
+ goto repeat;
+ }
+ VM_BUG_ON_PAGE(page->index != offset, page);
+ }
+
+ if (page && (fgp_flags & FGP_ACCESSED))
+ mark_page_accessed(page);
+
+no_page:
+ if (!page && (fgp_flags & FGP_CREAT)) {
+ int err;
+ if ((fgp_flags & FGP_WRITE) && mapping_cap_account_dirty(mapping))
+ cache_gfp_mask |= __GFP_WRITE;
+ if (fgp_flags & FGP_NOFS) {
+ cache_gfp_mask &= ~__GFP_FS;
+ radix_gfp_mask &= ~__GFP_FS;
+ }
+
+ page = __page_cache_alloc(cache_gfp_mask);
if (!page)
return NULL;
- /*
- * We want a regular kernel memory (not highmem or DMA etc)
- * allocation for the radix tree nodes, but we need to honour
- * the context-specific requirements the caller has asked for.
- * GFP_RECLAIM_MASK collects those requirements.
- */
- err = add_to_page_cache_lru(page, mapping, index,
- (gfp_mask & GFP_RECLAIM_MASK));
+
+ if (WARN_ON_ONCE(!(fgp_flags & FGP_LOCK)))
+ fgp_flags |= FGP_LOCK;
+
+ /* Init accessed so avoit atomic mark_page_accessed later */
+ if (fgp_flags & FGP_ACCESSED)
+ init_page_accessed(page);
+
+ err = add_to_page_cache_lru(page, mapping, offset, radix_gfp_mask);
if (unlikely(err)) {
page_cache_release(page);
page = NULL;
goto repeat;
}
}
+
return page;
}
-EXPORT_SYMBOL(find_or_create_page);
+EXPORT_SYMBOL(pagecache_get_page);
/**
* find_get_entries - gang pagecache lookup
}
EXPORT_SYMBOL(find_get_pages_tag);
-/**
- * grab_cache_page_nowait - returns locked page at given index in given cache
- * @mapping: target address_space
- * @index: the page index
- *
- * Same as grab_cache_page(), but do not wait if the page is unavailable.
- * This is intended for speculative data generators, where the data can
- * be regenerated if the page couldn't be grabbed. This routine should
- * be safe to call while holding the lock for another page.
- *
- * Clear __GFP_FS when allocating the page to avoid recursion into the fs
- * and deadlock against the caller's locked page.
- */
-struct page *
-grab_cache_page_nowait(struct address_space *mapping, pgoff_t index)
-{
- struct page *page = find_get_page(mapping, index);
-
- if (page) {
- if (trylock_page(page))
- return page;
- page_cache_release(page);
- return NULL;
- }
- page = __page_cache_alloc(mapping_gfp_mask(mapping) & ~__GFP_FS);
- if (page && add_to_page_cache_lru(page, mapping, index, GFP_NOFS)) {
- page_cache_release(page);
- page = NULL;
- }
- return page;
-}
-EXPORT_SYMBOL(grab_cache_page_nowait);
-
/*
* CD/DVDs are error prone. When a medium error occurs, the driver may fail
* a _large_ part of the i/o request. Imagine the worst scenario:
{
const struct address_space_operations *aops = mapping->a_ops;
- mark_page_accessed(page);
return aops->write_end(file, mapping, pos, len, copied, page, fsdata);
}
EXPORT_SYMBOL(pagecache_write_end);
struct page *grab_cache_page_write_begin(struct address_space *mapping,
pgoff_t index, unsigned flags)
{
- int status;
- gfp_t gfp_mask;
struct page *page;
- gfp_t gfp_notmask = 0;
+ int fgp_flags = FGP_LOCK|FGP_ACCESSED|FGP_WRITE|FGP_CREAT;
- gfp_mask = mapping_gfp_mask(mapping);
- if (mapping_cap_account_dirty(mapping))
- gfp_mask |= __GFP_WRITE;
if (flags & AOP_FLAG_NOFS)
- gfp_notmask = __GFP_FS;
-repeat:
- page = find_lock_page(mapping, index);
+ fgp_flags |= FGP_NOFS;
+
+ page = pagecache_get_page(mapping, index, fgp_flags,
+ mapping_gfp_mask(mapping),
+ GFP_KERNEL);
if (page)
- goto found;
+ wait_for_stable_page(page);
- page = __page_cache_alloc(gfp_mask & ~gfp_notmask);
- if (!page)
- return NULL;
- status = add_to_page_cache_lru(page, mapping, index,
- GFP_KERNEL & ~gfp_notmask);
- if (unlikely(status)) {
- page_cache_release(page);
- if (status == -EEXIST)
- goto repeat;
- return NULL;
- }
-found:
- wait_for_stable_page(page);
return page;
}
EXPORT_SYMBOL(grab_cache_page_write_begin);
status = a_ops->write_begin(file, mapping, pos, bytes, flags,
&page, &fsdata);
- if (unlikely(status))
+ if (unlikely(status < 0))
break;
if (mapping_writably_mapped(mapping))
copied = iov_iter_copy_from_user_atomic(page, i, offset, bytes);
flush_dcache_page(page);
- mark_page_accessed(page);
status = a_ops->write_end(file, mapping, pos, bytes, copied,
page, fsdata);
if (unlikely(status < 0))
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
+ int ret;
struct inode *inode = mapping->host;
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
- return shmem_getpage(inode, index, pagep, SGP_WRITE, NULL);
+ ret = shmem_getpage(inode, index, pagep, SGP_WRITE, NULL);
+ if (ret == 0 && *pagep)
+ init_page_accessed(*pagep);
+ return ret;
}
static int
}
EXPORT_SYMBOL(mark_page_accessed);
+/*
+ * Used to mark_page_accessed(page) that is not visible yet and when it is
+ * still safe to use non-atomic ops
+ */
+void init_page_accessed(struct page *page)
+{
+ if (!PageReferenced(page))
+ __SetPageReferenced(page);
+}
+EXPORT_SYMBOL(init_page_accessed);
+
static void __lru_cache_add(struct page *page)
{
struct pagevec *pvec = &get_cpu_var(lru_add_pvec);