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

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix reservations in btrfs_page_mkwrite
  Btrfs: advance window_start if we're using a bitmap
  btrfs: mask out gfp flags in releasepage
  Btrfs: fix enospc error caused by wrong checks of the chunk
  Btrfs: do not defrag a file partially
  Btrfs: fix warning for 32-bit build of fs/btrfs/check-integrity.c
  Btrfs: use cluster->window_start when allocating from a cluster bitmap
  Btrfs: Check for NULL page in extent_range_uptodate
  btrfs: Fix busyloops in transaction waiting code
  Btrfs: make sure a bitmap has enough bytes
  Btrfs: fix uninit warning in backref.c

1 files changed, 8 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 0da19a0ea00d..32214fe0f7e3 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6401,18 +6401,23 @@ int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
         unsigned long zero_start;
         loff_t size;
         int ret;
+        int reserved = 0;
         u64 page_start;
         u64 page_end;
 
         ret  = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
-        if (!ret)
+        if (!ret) {
                 ret = btrfs_update_time(vma->vm_file);
+                reserved = 1;
+        }
         if (ret) {
                 if (ret == -ENOMEM)
                         ret = VM_FAULT_OOM;
                 else /* -ENOSPC, -EIO, etc */
                         ret = VM_FAULT_SIGBUS;
-                goto out;
+                if (reserved)
+                        goto out;
+                goto out_noreserve;
         }
 
         ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
@@ -6495,6 +6500,7 @@ out_unlock:
         unlock_page(page);
 out:
         btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
+out_noreserve:
         return ret;
 }