diff options
Diffstat (limited to 'fs/btrfs')
-rw-r--r-- | fs/btrfs/inode.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 45cf03ee1bc..2e25d698bab 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4156,11 +4156,6 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, return -EINVAL; } -static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock) -{ - return extent_bmap(mapping, iblock, btrfs_get_extent); -} - int btrfs_readpage(struct file *file, struct page *page) { struct extent_io_tree *tree; @@ -4985,13 +4980,24 @@ static struct extent_io_ops btrfs_extent_io_ops = { .clear_bit_hook = btrfs_clear_bit_hook, }; +/* + * btrfs doesn't support the bmap operation because swapfiles + * use bmap to make a mapping of extents in the file. They assume + * these extents won't change over the life of the file and they + * use the bmap result to do IO directly to the drive. + * + * the btrfs bmap call would return logical addresses that aren't + * suitable for IO and they also will change frequently as COW + * operations happen. So, swapfile + btrfs == corruption. + * + * For now we're avoiding this by dropping bmap. + */ static struct address_space_operations btrfs_aops = { .readpage = btrfs_readpage, .writepage = btrfs_writepage, .writepages = btrfs_writepages, .readpages = btrfs_readpages, .sync_page = block_sync_page, - .bmap = btrfs_bmap, .direct_IO = btrfs_direct_IO, .invalidatepage = btrfs_invalidatepage, .releasepage = btrfs_releasepage, |