Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
 "We've had a busy two weeks of bug fixing.  The biggest patches in here
  are some long standing early-enospc problems (Josef) and a very old
  race where compression and mmap combine forces to lose writes (me).
  I'm fairly sure the mmap bug goes all the way back to the introduction
  of the compression code, which is proof that fsx doesn't trigger every
  possible mmap corner after all.

  I'm sure you'll notice one of these is from this morning, it's a small
  and isolated use-after-free fix in our scrub error reporting.  I
  double checked it here."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: don't drop path when printing out tree errors in scrub
  Btrfs: fix wrong return value of btrfs_lookup_csum()
  Btrfs: fix wrong reservation of csums
  Btrfs: fix double free in the btrfs_qgroup_account_ref()
  Btrfs: limit the global reserve to 512mb
  Btrfs: hold the ordered operations mutex when waiting on ordered extents
  Btrfs: fix space accounting for unlink and rename
  Btrfs: fix space leak when we fail to reserve metadata space
  Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holes
  Btrfs: fix race between mmap writes and compression
  Btrfs: fix memory leak in btrfs_create_tree()
  Btrfs: fix locking on ROOT_REPLACE operations in tree mod log
  Btrfs: fix missing qgroup reservation before fallocating
  Btrfs: handle a bogus chunk tree nicely
  Btrfs: update to use fs_state bit

1 files changed, 18 insertions, 4 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ca1b767d51f7..09c58a35b429 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -353,6 +353,7 @@ static noinline int compress_file_range(struct inode *inode,
         int i;
         int will_compress;
         int compress_type = root->fs_info->compress_type;
+        int redirty = 0;
 
         /* if this is a small write inside eof, kick off a defrag */
         if ((end - start + 1) < 16 * 1024 &&
@@ -415,6 +416,17 @@ again:
                 if (BTRFS_I(inode)->force_compress)
                         compress_type = BTRFS_I(inode)->force_compress;
 
+                /*
+                 * we need to call clear_page_dirty_for_io on each
+                 * page in the range.  Otherwise applications with the file
+                 * mmap'd can wander in and change the page contents while
+                 * we are compressing them.
+                 *
+                 * If the compression fails for any reason, we set the pages
+                 * dirty again later on.
+                 */
+                extent_range_clear_dirty_for_io(inode, start, end);
+                redirty = 1;
                 ret = btrfs_compress_pages(compress_type,
                                            inode->i_mapping, start,
                                            total_compressed, pages,
@@ -554,6 +566,8 @@ cleanup_and_bail_uncompressed:
                         __set_page_dirty_nobuffers(locked_page);
                         /* unlocked later on in the async handlers */
                 }
+                if (redirty)
+                        extent_range_redirty_for_io(inode, start, end);
                 add_async_extent(async_cow, start, end - start + 1,
                                  0, NULL, 0, BTRFS_COMPRESS_NONE);
                 *num_added += 1;
@@ -1743,8 +1757,10 @@ static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
         struct btrfs_ordered_sum *sum;
 
         list_for_each_entry(sum, list, list) {
+                trans->adding_csums = 1;
                 btrfs_csum_file_blocks(trans,
                        BTRFS_I(inode)->root->fs_info->csum_root, sum);
+                trans->adding_csums = 0;
         }
         return 0;
 }
@@ -3679,11 +3695,9 @@ static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
          * 1 for the dir item
          * 1 for the dir index
          * 1 for the inode ref
-         * 1 for the inode ref in the tree log
-         * 2 for the dir entries in the log
          * 1 for the inode
          */
-        trans = btrfs_start_transaction(root, 8);
+        trans = btrfs_start_transaction(root, 5);
         if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
                 return trans;
 
@@ -8127,7 +8141,7 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
          * inodes.  So 5 * 2 is 10, plus 1 for the new link, so 11 total items
          * should cover the worst case number of items we'll modify.
          */
-        trans = btrfs_start_transaction(root, 20);
+        trans = btrfs_start_transaction(root, 11);
         if (IS_ERR(trans)) {
                 ret = PTR_ERR(trans);
                 goto out_notrans;