1 files changed, 28 insertions, 3 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index e4090259569b..b476e5645034 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2276,6 +2276,8 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
         bool same_page;
         bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES);
         u64 ino_size;
+        bool truncated_page = false;
+        bool updated_inode = false;
 
         ret = btrfs_wait_ordered_range(inode, offset, len);
         if (ret)
@@ -2307,13 +2309,18 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
          * entire page.
          */
         if (same_page && len < PAGE_CACHE_SIZE) {
-                if (offset < ino_size)
+                if (offset < ino_size) {
+                        truncated_page = true;
                         ret = btrfs_truncate_page(inode, offset, len, 0);
+                } else {
+                        ret = 0;
+                }
                 goto out_only_mutex;
         }
 
         /* zero back part of the first page */
         if (offset < ino_size) {
+                truncated_page = true;
                 ret = btrfs_truncate_page(inode, offset, 0, 0);
                 if (ret) {
                         mutex_unlock(&inode->i_mutex);
@@ -2349,6 +2356,7 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
                 if (!ret) {
                         /* zero the front end of the last page */
                         if (tail_start + tail_len < ino_size) {
+                                truncated_page = true;
                                 ret = btrfs_truncate_page(inode,
                                                 tail_start + tail_len, 0, 1);
                                 if (ret)
@@ -2358,8 +2366,8 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
         }
 
         if (lockend < lockstart) {
-                mutex_unlock(&inode->i_mutex);
-                return 0;
+                ret = 0;
+                goto out_only_mutex;
         }
 
         while (1) {
@@ -2507,6 +2515,7 @@ out_trans:
 
         trans->block_rsv = &root->fs_info->trans_block_rsv;
         ret = btrfs_update_inode(trans, root, inode);
+        updated_inode = true;
         btrfs_end_transaction(trans, root);
         btrfs_btree_balance_dirty(root);
 out_free:
@@ -2516,6 +2525,22 @@ out:
         unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
                              &cached_state, GFP_NOFS);
 out_only_mutex:
+        if (!updated_inode && truncated_page && !ret && !err) {
+                /*
+                 * If we only end up zeroing part of a page, we still need to
+                 * update the inode item, so that all the time fields are
+                 * updated as well as the necessary btrfs inode in memory fields
+                 * for detecting, at fsync time, if the inode isn't yet in the
+                 * log tree or it's there but not up to date.
+                 */
+                trans = btrfs_start_transaction(root, 1);
+                if (IS_ERR(trans)) {
+                        err = PTR_ERR(trans);
+                } else {
+                        err = btrfs_update_inode(trans, root, inode);
+                        ret = btrfs_end_transaction(trans, root);
+                }
+        }
         mutex_unlock(&inode->i_mutex);
         if (ret && !err)
                 err = ret;