diff options
Diffstat (limited to 'fs/buffer.c')
-rw-r--r-- | fs/buffer.c | 50 |
1 files changed, 23 insertions, 27 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index 838a9cf246bd..9f6d2e41281d 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1036,6 +1036,9 @@ grow_buffers(struct block_device *bdev, sector_t block, int size) static struct buffer_head * __getblk_slow(struct block_device *bdev, sector_t block, int size) { + int ret; + struct buffer_head *bh; + /* Size must be multiple of hard sectorsize */ if (unlikely(size & (bdev_logical_block_size(bdev)-1) || (size < 512 || size > PAGE_SIZE))) { @@ -1048,20 +1051,21 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size) return NULL; } - for (;;) { - struct buffer_head * bh; - int ret; +retry: + bh = __find_get_block(bdev, block, size); + if (bh) + return bh; + ret = grow_buffers(bdev, block, size); + if (ret == 0) { + free_more_memory(); + goto retry; + } else if (ret > 0) { bh = __find_get_block(bdev, block, size); if (bh) return bh; - - ret = grow_buffers(bdev, block, size); - if (ret < 0) - return NULL; - if (ret == 0) - free_more_memory(); } + return NULL; } /* @@ -2302,8 +2306,8 @@ EXPORT_SYMBOL(block_commit_write); * beyond EOF, then the page is guaranteed safe against truncation until we * unlock the page. * - * Direct callers of this function should call vfs_check_frozen() so that page - * fault does not busyloop until the fs is thawed. + * Direct callers of this function should protect against filesystem freezing + * using sb_start_write() - sb_end_write() functions. */ int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, get_block_t get_block) @@ -2314,6 +2318,12 @@ int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, loff_t size; int ret; + /* + * Update file times before taking page lock. We may end up failing the + * fault so this update may be superfluous but who really cares... + */ + file_update_time(vma->vm_file); + lock_page(page); size = i_size_read(inode); if ((page->mapping != inode->i_mapping) || @@ -2335,18 +2345,7 @@ int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, if (unlikely(ret < 0)) goto out_unlock; - /* - * Freezing in progress? We check after the page is marked dirty and - * with page lock held so if the test here fails, we are sure freezing - * code will wait during syncing until the page fault is done - at that - * point page will be dirty and unlocked so freezing code will write it - * and writeprotect it again. - */ set_page_dirty(page); - if (inode->i_sb->s_frozen != SB_UNFROZEN) { - ret = -EAGAIN; - goto out_unlock; - } wait_on_page_writeback(page); return 0; out_unlock: @@ -2361,12 +2360,9 @@ int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, int ret; struct super_block *sb = vma->vm_file->f_path.dentry->d_inode->i_sb; - /* - * This check is racy but catches the common case. The check in - * __block_page_mkwrite() is reliable. - */ - vfs_check_frozen(sb, SB_FREEZE_WRITE); + sb_start_pagefault(sb); ret = __block_page_mkwrite(vma, vmf, get_block); + sb_end_pagefault(sb); return block_page_mkwrite_return(ret); } EXPORT_SYMBOL(block_page_mkwrite); |