diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/block_dev.c | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index 9cb205405f9d..c70c41ecba48 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -103,6 +103,35 @@ void invalidate_bdev(struct block_device *bdev) } EXPORT_SYMBOL(invalidate_bdev); +/* + * Drop all buffers & page cache for given bdev range. This function bails + * with error if bdev has other exclusive owner (such as filesystem). + */ +int truncate_bdev_range(struct block_device *bdev, fmode_t mode, + loff_t lstart, loff_t lend) +{ + struct block_device *claimed_bdev = NULL; + int err; + + /* + * If we don't hold exclusive handle for the device, upgrade to it + * while we discard the buffer cache to avoid discarding buffers + * under live filesystem. + */ + if (!(mode & FMODE_EXCL)) { + claimed_bdev = bdev->bd_contains; + err = bd_prepare_to_claim(bdev, claimed_bdev, + truncate_bdev_range); + if (err) + return err; + } + truncate_inode_pages_range(bdev->bd_inode->i_mapping, lstart, lend); + if (claimed_bdev) + bd_abort_claiming(bdev, claimed_bdev, truncate_bdev_range); + return 0; +} +EXPORT_SYMBOL(truncate_bdev_range); + static void set_init_blocksize(struct block_device *bdev) { bdev->bd_inode->i_blkbits = blksize_bits(bdev_logical_block_size(bdev)); @@ -1968,7 +1997,6 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, loff_t len) { struct block_device *bdev = I_BDEV(bdev_file_inode(file)); - struct address_space *mapping; loff_t end = start + len - 1; loff_t isize; int error; @@ -1996,8 +2024,9 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, return -EINVAL; /* Invalidate the page cache, including dirty pages. */ - mapping = bdev->bd_inode->i_mapping; - truncate_inode_pages_range(mapping, start, end); + error = truncate_bdev_range(bdev, file->f_mode, start, end); + if (error) + return error; switch (mode) { case FALLOC_FL_ZERO_RANGE: @@ -2024,7 +2053,7 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, * the caller will be given -EBUSY. The third argument is * inclusive, so the rounding here is safe. */ - return invalidate_inode_pages2_range(mapping, + return invalidate_inode_pages2_range(bdev->bd_inode->i_mapping, start >> PAGE_SHIFT, end >> PAGE_SHIFT); } |