diff options
Diffstat (limited to 'fs/buffer.c')
-rw-r--r-- | fs/buffer.c | 306 |
1 files changed, 160 insertions, 146 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index d3bcf601d3e5..cc8452f60251 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -55,7 +55,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list); static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh, - struct writeback_control *wbc); + enum rw_hint hint, struct writeback_control *wbc); #define BH_ENTRY(list) list_entry((list), struct buffer_head, b_assoc_buffers) @@ -189,8 +189,8 @@ EXPORT_SYMBOL(end_buffer_write_sync); static struct buffer_head * __find_get_block_slow(struct block_device *bdev, sector_t block) { - struct inode *bd_inode = bdev->bd_inode; - struct address_space *bd_mapping = bd_inode->i_mapping; + struct address_space *bd_mapping = bdev->bd_mapping; + const int blkbits = bd_mapping->host->i_blkbits; struct buffer_head *ret = NULL; pgoff_t index; struct buffer_head *bh; @@ -199,7 +199,7 @@ __find_get_block_slow(struct block_device *bdev, sector_t block) int all_mapped = 1; static DEFINE_RATELIMIT_STATE(last_warned, HZ, 1); - index = ((loff_t)block << bd_inode->i_blkbits) / PAGE_SIZE; + index = ((loff_t)block << blkbits) / PAGE_SIZE; folio = __filemap_get_folio(bd_mapping, index, FGP_ACCESSED, 0); if (IS_ERR(folio)) goto out; @@ -233,7 +233,7 @@ __find_get_block_slow(struct block_device *bdev, sector_t block) (unsigned long long)block, (unsigned long long)bh->b_blocknr, bh->b_state, bh->b_size, bdev, - 1 << bd_inode->i_blkbits); + 1 << blkbits); } out_unlock: spin_unlock(&bd_mapping->i_private_lock); @@ -258,7 +258,6 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate) } else { clear_buffer_uptodate(bh); buffer_io_error(bh, ", async page read"); - folio_set_error(folio); } /* @@ -391,7 +390,6 @@ static void end_buffer_async_write(struct buffer_head *bh, int uptodate) buffer_io_error(bh, ", lost async page write"); mark_buffer_write_io_error(bh); clear_buffer_uptodate(bh); - folio_set_error(folio); } first = folio_buffers(folio); @@ -464,7 +462,7 @@ EXPORT_SYMBOL(mark_buffer_async_write); * a successful fsync(). For example, ext2 indirect blocks need to be * written back and waited upon before fsync() returns. * - * The functions mark_buffer_inode_dirty(), fsync_inode_buffers(), + * The functions mark_buffer_dirty_inode(), fsync_inode_buffers(), * inode_has_buffers() and invalidate_inode_buffers() are provided for the * management of a list of dependent buffers at ->i_mapping->i_private_list. * @@ -687,30 +685,37 @@ void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode) } EXPORT_SYMBOL(mark_buffer_dirty_inode); -/* - * Add a page to the dirty page list. - * - * It is a sad fact of life that this function is called from several places - * deeply under spinlocking. It may not sleep. - * - * If the page has buffers, the uptodate buffers are set dirty, to preserve - * dirty-state coherency between the page and the buffers. It the page does - * not have buffers then when they are later attached they will all be set - * dirty. - * - * The buffers are dirtied before the page is dirtied. There's a small race - * window in which a writepage caller may see the page cleanness but not the - * buffer dirtiness. That's fine. If this code were to set the page dirty - * before the buffers, a concurrent writepage caller could clear the page dirty - * bit, see a bunch of clean buffers and we'd end up with dirty buffers/clean - * page on the dirty page list. - * - * We use i_private_lock to lock against try_to_free_buffers while using the - * page's buffer list. Also use this to protect against clean buffers being - * added to the page after it was set dirty. - * - * FIXME: may need to call ->reservepage here as well. That's rather up to the - * address_space though. +/** + * block_dirty_folio - Mark a folio as dirty. + * @mapping: The address space containing this folio. + * @folio: The folio to mark dirty. + * + * Filesystems which use buffer_heads can use this function as their + * ->dirty_folio implementation. Some filesystems need to do a little + * work before calling this function. Filesystems which do not use + * buffer_heads should call filemap_dirty_folio() instead. + * + * If the folio has buffers, the uptodate buffers are set dirty, to + * preserve dirty-state coherency between the folio and the buffers. + * Buffers added to a dirty folio are created dirty. + * + * The buffers are dirtied before the folio is dirtied. There's a small + * race window in which writeback may see the folio cleanness but not the + * buffer dirtiness. That's fine. If this code were to set the folio + * dirty before the buffers, writeback could clear the folio dirty flag, + * see a bunch of clean buffers and we'd end up with dirty buffers/clean + * folio on the dirty folio list. + * + * We use i_private_lock to lock against try_to_free_buffers() while + * using the folio's buffer list. This also prevents clean buffers + * being added to the folio after it was set dirty. + * + * Context: May only be called from process context. Does not sleep. + * Caller must ensure that @folio cannot be truncated during this call, + * typically by holding the folio lock or having a page in the folio + * mapped and holding the page table lock. + * + * Return: True if the folio was dirtied; false if it was already dirtied. */ bool block_dirty_folio(struct address_space *mapping, struct folio *folio) { @@ -731,15 +736,12 @@ bool block_dirty_folio(struct address_space *mapping, struct folio *folio) * Lock out page's memcg migration to keep PageDirty * synchronized with per-memcg dirty page counters. */ - folio_memcg_lock(folio); newly_dirty = !folio_test_set_dirty(folio); spin_unlock(&mapping->i_private_lock); if (newly_dirty) __folio_mark_dirty(folio, mapping, 1); - folio_memcg_unlock(folio); - if (newly_dirty) __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); @@ -769,12 +771,11 @@ EXPORT_SYMBOL(block_dirty_folio); static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) { struct buffer_head *bh; - struct list_head tmp; struct address_space *mapping; int err = 0, err2; struct blk_plug plug; + LIST_HEAD(tmp); - INIT_LIST_HEAD(&tmp); blk_start_plug(&plug); spin_lock(lock); @@ -851,8 +852,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) * done a sync(). Just drop the buffers from the inode list. * * NOTE: we take the inode's blockdev's mapping's i_private_lock. Which - * assumes that all the buffers are against the blockdev. Not true - * for reiserfs. + * assumes that all the buffers are against the blockdev. */ void invalidate_inode_buffers(struct inode *inode) { @@ -953,12 +953,9 @@ no_grow: } EXPORT_SYMBOL_GPL(folio_alloc_buffers); -struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, - bool retry) +struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size) { gfp_t gfp = GFP_NOFS | __GFP_ACCOUNT; - if (retry) - gfp |= __GFP_NOFAIL; return folio_alloc_buffers(page_folio(page), size, gfp); } @@ -1034,12 +1031,12 @@ static sector_t folio_init_buffers(struct folio *folio, static bool grow_dev_folio(struct block_device *bdev, sector_t block, pgoff_t index, unsigned size, gfp_t gfp) { - struct inode *inode = bdev->bd_inode; + struct address_space *mapping = bdev->bd_mapping; struct folio *folio; struct buffer_head *bh; sector_t end_block = 0; - folio = __filemap_get_folio(inode->i_mapping, index, + folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_ACCESSED | FGP_CREAT, gfp); if (IS_ERR(folio)) return false; @@ -1073,10 +1070,10 @@ static bool grow_dev_folio(struct block_device *bdev, sector_t block, * lock to be atomic wrt __find_get_block(), which does not * run under the folio lock. */ - spin_lock(&inode->i_mapping->i_private_lock); + spin_lock(&mapping->i_private_lock); link_dev_buffers(folio, bh); end_block = folio_init_buffers(folio, bdev, size); - spin_unlock(&inode->i_mapping->i_private_lock); + spin_unlock(&mapping->i_private_lock); unlock: folio_unlock(folio); folio_put(folio); @@ -1193,13 +1190,11 @@ void mark_buffer_dirty(struct buffer_head *bh) struct folio *folio = bh->b_folio; struct address_space *mapping = NULL; - folio_memcg_lock(folio); if (!folio_test_set_dirty(folio)) { mapping = folio->mapping; if (mapping) __folio_mark_dirty(folio, mapping, 0); } - folio_memcg_unlock(folio); if (mapping) __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); } @@ -1219,26 +1214,28 @@ void mark_buffer_write_io_error(struct buffer_head *bh) } EXPORT_SYMBOL(mark_buffer_write_io_error); -/* - * Decrement a buffer_head's reference count. If all buffers against a page - * have zero reference count, are clean and unlocked, and if the page is clean - * and unlocked then try_to_free_buffers() may strip the buffers from the page - * in preparation for freeing it (sometimes, rarely, buffers are removed from - * a page but it ends up not being freed, and buffers may later be reattached). +/** + * __brelse - Release a buffer. + * @bh: The buffer to release. + * + * This variant of brelse() can be called if @bh is guaranteed to not be NULL. */ -void __brelse(struct buffer_head * buf) +void __brelse(struct buffer_head *bh) { - if (atomic_read(&buf->b_count)) { - put_bh(buf); + if (atomic_read(&bh->b_count)) { + put_bh(bh); return; } WARN(1, KERN_ERR "VFS: brelse: Trying to free free buffer\n"); } EXPORT_SYMBOL(__brelse); -/* - * bforget() is like brelse(), except it discards any - * potentially dirty data. +/** + * __bforget - Discard any dirty data in a buffer. + * @bh: The buffer to forget. + * + * This variant of bforget() can be called if @bh is guaranteed to not + * be NULL. */ void __bforget(struct buffer_head *bh) { @@ -1415,6 +1412,11 @@ EXPORT_SYMBOL(__find_get_block); * @size: The size of buffer_heads for this @bdev. * @gfp: The memory allocation flags to use. * + * The returned buffer head has its reference count incremented, but is + * not locked. The caller should call brelse() when it has finished + * with the buffer. The buffer may not be uptodate. If needed, the + * caller can bring it uptodate either by reading it or overwriting it. + * * Return: The buffer head, or NULL if memory could not be allocated. */ struct buffer_head *bdev_getblk(struct block_device *bdev, sector_t block, @@ -1446,24 +1448,33 @@ void __breadahead(struct block_device *bdev, sector_t block, unsigned size) EXPORT_SYMBOL(__breadahead); /** - * __bread_gfp() - reads a specified block and returns the bh - * @bdev: the block_device to read from - * @block: number of block - * @size: size (in bytes) to read - * @gfp: page allocation flag - * - * Reads a specified block, and returns buffer head that contains it. - * The page cache can be allocated from non-movable area - * not to prevent page migration if you set gfp to zero. - * It returns NULL if the block was unreadable. + * __bread_gfp() - Read a block. + * @bdev: The block device to read from. + * @block: Block number in units of block size. + * @size: The block size of this device in bytes. + * @gfp: Not page allocation flags; see below. + * + * You are not expected to call this function. You should use one of + * sb_bread(), sb_bread_unmovable() or __bread(). + * + * Read a specified block, and return the buffer head that refers to it. + * If @gfp is 0, the memory will be allocated using the block device's + * default GFP flags. If @gfp is __GFP_MOVABLE, the memory may be + * allocated from a movable area. Do not pass in a complete set of + * GFP flags. + * + * The returned buffer head has its refcount increased. The caller should + * call brelse() when it has finished with the buffer. + * + * Context: May sleep waiting for I/O. + * Return: NULL if the block was unreadable. */ -struct buffer_head * -__bread_gfp(struct block_device *bdev, sector_t block, - unsigned size, gfp_t gfp) +struct buffer_head *__bread_gfp(struct block_device *bdev, sector_t block, + unsigned size, gfp_t gfp) { struct buffer_head *bh; - gfp |= mapping_gfp_constraint(bdev->bd_inode->i_mapping, ~__GFP_FS); + gfp |= mapping_gfp_constraint(bdev->bd_mapping, ~__GFP_FS); /* * Prefer looping in the allocator rather than here, at least that @@ -1632,6 +1643,7 @@ void block_invalidate_folio(struct folio *folio, size_t offset, size_t length) if (length == folio_size(folio)) filemap_release_folio(folio, 0); out: + folio_clear_mappedtodisk(folio); return; } EXPORT_SYMBOL(block_invalidate_folio); @@ -1696,16 +1708,16 @@ EXPORT_SYMBOL(create_empty_buffers); */ void clean_bdev_aliases(struct block_device *bdev, sector_t block, sector_t len) { - struct inode *bd_inode = bdev->bd_inode; - struct address_space *bd_mapping = bd_inode->i_mapping; + struct address_space *bd_mapping = bdev->bd_mapping; + const int blkbits = bd_mapping->host->i_blkbits; struct folio_batch fbatch; - pgoff_t index = ((loff_t)block << bd_inode->i_blkbits) / PAGE_SIZE; + pgoff_t index = ((loff_t)block << blkbits) / PAGE_SIZE; pgoff_t end; int i, count; struct buffer_head *bh; struct buffer_head *head; - end = ((loff_t)(block + len - 1) << bd_inode->i_blkbits) / PAGE_SIZE; + end = ((loff_t)(block + len - 1) << blkbits) / PAGE_SIZE; folio_batch_init(&fbatch); while (filemap_get_folios(bd_mapping, &index, end, &fbatch)) { count = folio_batch_count(&fbatch); @@ -1889,7 +1901,8 @@ int __block_write_full_folio(struct inode *inode, struct folio *folio, do { struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { - submit_bh_wbc(REQ_OP_WRITE | write_flags, bh, wbc); + submit_bh_wbc(REQ_OP_WRITE | write_flags, bh, + inode->i_write_hint, wbc); nr_underway++; } bh = next; @@ -1936,7 +1949,6 @@ recover: clear_buffer_dirty(bh); } } while ((bh = bh->b_this_page) != head); - folio_set_error(folio); BUG_ON(folio_test_writeback(folio)); mapping_set_error(folio->mapping, err); folio_start_writeback(folio); @@ -1944,7 +1956,8 @@ recover: struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { clear_buffer_dirty(bh); - submit_bh_wbc(REQ_OP_WRITE | write_flags, bh, wbc); + submit_bh_wbc(REQ_OP_WRITE | write_flags, bh, + inode->i_write_hint, wbc); nr_underway++; } bh = next; @@ -2146,11 +2159,10 @@ int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len, return err; } -int __block_write_begin(struct page *page, loff_t pos, unsigned len, +int __block_write_begin(struct folio *folio, loff_t pos, unsigned len, get_block_t *get_block) { - return __block_write_begin_int(page_folio(page), pos, len, get_block, - NULL); + return __block_write_begin_int(folio, pos, len, get_block, NULL); } EXPORT_SYMBOL(__block_write_begin); @@ -2162,6 +2174,8 @@ static void __block_commit_write(struct folio *folio, size_t from, size_t to) struct buffer_head *bh, *head; bh = head = folio_buffers(folio); + if (!bh) + return; blocksize = bh->b_size; block_start = 0; @@ -2198,33 +2212,33 @@ static void __block_commit_write(struct folio *folio, size_t from, size_t to) * The filesystem needs to handle block truncation upon failure. */ int block_write_begin(struct address_space *mapping, loff_t pos, unsigned len, - struct page **pagep, get_block_t *get_block) + struct folio **foliop, get_block_t *get_block) { pgoff_t index = pos >> PAGE_SHIFT; - struct page *page; + struct folio *folio; int status; - page = grab_cache_page_write_begin(mapping, index); - if (!page) - return -ENOMEM; + folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, + mapping_gfp_mask(mapping)); + if (IS_ERR(folio)) + return PTR_ERR(folio); - status = __block_write_begin(page, pos, len, get_block); + status = __block_write_begin_int(folio, pos, len, get_block, NULL); if (unlikely(status)) { - unlock_page(page); - put_page(page); - page = NULL; + folio_unlock(folio); + folio_put(folio); + folio = NULL; } - *pagep = page; + *foliop = folio; return status; } EXPORT_SYMBOL(block_write_begin); int block_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) + struct folio *folio, void *fsdata) { - struct folio *folio = page_folio(page); size_t start = pos - folio_pos(folio); if (unlikely(copied < len)) { @@ -2256,19 +2270,19 @@ EXPORT_SYMBOL(block_write_end); int generic_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) + struct folio *folio, void *fsdata) { struct inode *inode = mapping->host; loff_t old_size = inode->i_size; bool i_size_changed = false; - copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); + copied = block_write_end(file, mapping, pos, len, copied, folio, fsdata); /* * No need to use i_size_read() here, the i_size cannot change under us * because we hold i_rwsem. * - * But it's important to update i_size while still holding page lock: + * But it's important to update i_size while still holding folio lock: * page writeout could otherwise come in and zero beyond i_size. */ if (pos + copied > inode->i_size) { @@ -2276,8 +2290,8 @@ int generic_write_end(struct file *file, struct address_space *mapping, i_size_changed = true; } - unlock_page(page); - put_page(page); + folio_unlock(folio); + folio_put(folio); if (old_size < pos) pagecache_isize_extended(inode, old_size, pos); @@ -2380,10 +2394,8 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block) if (iblock < lblock) { WARN_ON(bh->b_size != blocksize); err = get_block(inode, iblock, bh, 0); - if (err) { - folio_set_error(folio); + if (err) page_error = true; - } } if (!buffer_mapped(bh)) { folio_zero_range(folio, i * blocksize, @@ -2445,7 +2457,7 @@ int generic_cont_expand_simple(struct inode *inode, loff_t size) { struct address_space *mapping = inode->i_mapping; const struct address_space_operations *aops = mapping->a_ops; - struct page *page; + struct folio *folio; void *fsdata = NULL; int err; @@ -2453,11 +2465,11 @@ int generic_cont_expand_simple(struct inode *inode, loff_t size) if (err) goto out; - err = aops->write_begin(NULL, mapping, size, 0, &page, &fsdata); + err = aops->write_begin(NULL, mapping, size, 0, &folio, &fsdata); if (err) goto out; - err = aops->write_end(NULL, mapping, size, 0, 0, page, fsdata); + err = aops->write_end(NULL, mapping, size, 0, 0, folio, fsdata); BUG_ON(err > 0); out: @@ -2471,7 +2483,7 @@ static int cont_expand_zero(struct file *file, struct address_space *mapping, struct inode *inode = mapping->host; const struct address_space_operations *aops = mapping->a_ops; unsigned int blocksize = i_blocksize(inode); - struct page *page; + struct folio *folio; void *fsdata = NULL; pgoff_t index, curidx; loff_t curpos; @@ -2490,12 +2502,12 @@ static int cont_expand_zero(struct file *file, struct address_space *mapping, len = PAGE_SIZE - zerofrom; err = aops->write_begin(file, mapping, curpos, len, - &page, &fsdata); + &folio, &fsdata); if (err) goto out; - zero_user(page, zerofrom, len); + folio_zero_range(folio, offset_in_folio(folio, curpos), len); err = aops->write_end(file, mapping, curpos, len, len, - page, fsdata); + folio, fsdata); if (err < 0) goto out; BUG_ON(err != len); @@ -2523,12 +2535,12 @@ static int cont_expand_zero(struct file *file, struct address_space *mapping, len = offset - zerofrom; err = aops->write_begin(file, mapping, curpos, len, - &page, &fsdata); + &folio, &fsdata); if (err) goto out; - zero_user(page, zerofrom, len); + folio_zero_range(folio, offset_in_folio(folio, curpos), len); err = aops->write_end(file, mapping, curpos, len, len, - page, fsdata); + folio, fsdata); if (err < 0) goto out; BUG_ON(err != len); @@ -2544,7 +2556,7 @@ out: */ int cont_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, - struct page **pagep, void **fsdata, + struct folio **foliop, void **fsdata, get_block_t *get_block, loff_t *bytes) { struct inode *inode = mapping->host; @@ -2562,7 +2574,7 @@ int cont_write_begin(struct file *file, struct address_space *mapping, (*bytes)++; } - return block_write_begin(mapping, pos, len, pagep, get_block); + return block_write_begin(mapping, pos, len, foliop, get_block); } EXPORT_SYMBOL(cont_write_begin); @@ -2756,6 +2768,7 @@ static void end_bio_bh_io_sync(struct bio *bio) } static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh, + enum rw_hint write_hint, struct writeback_control *wbc) { const enum req_op op = opf & REQ_OP_MASK; @@ -2783,8 +2796,9 @@ static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh, fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO); bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); + bio->bi_write_hint = write_hint; - __bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh)); + bio_add_folio_nofail(bio, bh->b_folio, bh->b_size, bh_offset(bh)); bio->bi_end_io = end_bio_bh_io_sync; bio->bi_private = bh; @@ -2794,7 +2808,7 @@ static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh, if (wbc) { wbc_init_bio(wbc, bio); - wbc_account_cgroup_owner(wbc, bh->b_page, bh->b_size); + wbc_account_cgroup_owner(wbc, bh->b_folio, bh->b_size); } submit_bio(bio); @@ -2802,7 +2816,7 @@ static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh, void submit_bh(blk_opf_t opf, struct buffer_head *bh) { - submit_bh_wbc(opf, bh, NULL); + submit_bh_wbc(opf, bh, WRITE_LIFE_NOT_SET, NULL); } EXPORT_SYMBOL(submit_bh); @@ -2857,26 +2871,6 @@ int sync_dirty_buffer(struct buffer_head *bh) } EXPORT_SYMBOL(sync_dirty_buffer); -/* - * try_to_free_buffers() checks if all the buffers on this particular folio - * are unused, and releases them if so. - * - * Exclusion against try_to_free_buffers may be obtained by either - * locking the folio or by holding its mapping's i_private_lock. - * - * If the folio is dirty but all the buffers are clean then we need to - * be sure to mark the folio clean as well. This is because the folio - * may be against a block device, and a later reattachment of buffers - * to a dirty folio will set *all* buffers dirty. Which would corrupt - * filesystem data on the same device. - * - * The same applies to regular filesystem folios: if all the buffers are - * clean then we set the folio clean and proceed. To do that, we require - * total exclusion from block_dirty_folio(). That is obtained with - * i_private_lock. - * - * try_to_free_buffers() is non-blocking. - */ static inline int buffer_busy(struct buffer_head *bh) { return atomic_read(&bh->b_count) | @@ -2910,6 +2904,30 @@ failed: return false; } +/** + * try_to_free_buffers - Release buffers attached to this folio. + * @folio: The folio. + * + * If any buffers are in use (dirty, under writeback, elevated refcount), + * no buffers will be freed. + * + * If the folio is dirty but all the buffers are clean then we need to + * be sure to mark the folio clean as well. This is because the folio + * may be against a block device, and a later reattachment of buffers + * to a dirty folio will set *all* buffers dirty. Which would corrupt + * filesystem data on the same device. + * + * The same applies to regular filesystem folios: if all the buffers are + * clean then we set the folio clean and proceed. To do that, we require + * total exclusion from block_dirty_folio(). That is obtained with + * i_private_lock. + * + * Exclusion against try_to_free_buffers may be obtained by either + * locking the folio or by holding its mapping's i_private_lock. + * + * Context: Process context. @folio must be locked. Will not sleep. + * Return: true if all buffers attached to this folio were freed. + */ bool try_to_free_buffers(struct folio *folio) { struct address_space * const mapping = folio->mapping; @@ -3121,12 +3139,8 @@ void __init buffer_init(void) unsigned long nrpages; int ret; - bh_cachep = kmem_cache_create("buffer_head", - sizeof(struct buffer_head), 0, - (SLAB_RECLAIM_ACCOUNT|SLAB_PANIC| - SLAB_MEM_SPREAD), - NULL); - + bh_cachep = KMEM_CACHE(buffer_head, + SLAB_RECLAIM_ACCOUNT|SLAB_PANIC); /* * Limit the bh occupancy to 10% of ZONE_NORMAL */ |