1 files changed, 18 insertions, 7 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 8adfe059ab41..288c2cdc7543 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -34,7 +34,6 @@
 #include <linux/statfs.h>
 #include <linux/compat.h>
 #include <linux/bit_spinlock.h>
-#include <linux/version.h>
 #include <linux/xattr.h>
 #include <linux/posix_acl.h>
 #include <linux/falloc.h>
@@ -1324,12 +1323,11 @@ static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
                              struct inode *inode, u64 file_offset,
                              struct list_head *list)
 {
-        struct list_head *cur;
         struct btrfs_ordered_sum *sum;
 
         btrfs_set_trans_block_group(trans, inode);
-        list_for_each(cur, list) {
-                sum = list_entry(cur, struct btrfs_ordered_sum, list);
+
+        list_for_each_entry(sum, list, list) {
                 btrfs_csum_file_blocks(trans,
                        BTRFS_I(inode)->root->fs_info->csum_root, sum);
         }
@@ -4158,9 +4156,10 @@ 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)
+static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+                __u64 start, __u64 len)
 {
-        return extent_bmap(mapping, iblock, btrfs_get_extent);
+        return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent);
 }
 
 int btrfs_readpage(struct file *file, struct page *page)
@@ -4987,13 +4986,24 @@ 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,
@@ -5017,6 +5027,7 @@ static struct inode_operations btrfs_file_inode_operations = {
         .removexattr    = btrfs_removexattr,
         .permission     = btrfs_permission,
         .fallocate      = btrfs_fallocate,
+        .fiemap         = btrfs_fiemap,
 };
 static struct inode_operations btrfs_special_inode_operations = {
         .getattr        = btrfs_getattr,