xfs: use iomap new flag for newly allocated delalloc blocks

[mirror_ubuntu-zesty-kernel.git] / fs / xfs / xfs_iomap.c

diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index e8811bd1019b545f67e6c9020d4f88ab33ad6522..2326a6913fde0838ddc6969b7b35490d5fcee5b5 100644 (file)
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -637,6 +637,11 @@ retry:
                goto out_unlock;
        }
 
+       /*
+        * Flag newly allocated delalloc blocks with IOMAP_F_NEW so we punch
+        * them out if the write happens to fail.
+        */
+       iomap->flags = IOMAP_F_NEW;
        trace_xfs_iomap_alloc(ip, offset, count, 0, &got);
 done:
        if (isnullstartblock(got.br_startblock))
@@ -1085,7 +1090,8 @@ xfs_file_iomap_end_delalloc(
        struct xfs_inode        *ip,
        loff_t                  offset,
        loff_t                  length,
-       ssize_t                 written)
+       ssize_t                 written,
+       struct iomap            *iomap)
 {
        struct xfs_mount        *mp = ip->i_mount;
        xfs_fileoff_t           start_fsb;
@@ -1104,14 +1110,14 @@ xfs_file_iomap_end_delalloc(
        end_fsb = XFS_B_TO_FSB(mp, offset + length);
 
        /*
-        * Trim back delalloc blocks if we didn't manage to write the whole
-        * range reserved.
+        * Trim delalloc blocks if they were allocated by this write and we
+        * didn't manage to write the whole range.
         *
         * We don't need to care about racing delalloc as we hold i_mutex
         * across the reserve/allocate/unreserve calls. If there are delalloc
         * blocks in the range, they are ours.
         */
-       if (start_fsb < end_fsb) {
+       if ((iomap->flags & IOMAP_F_NEW) && start_fsb < end_fsb) {
                truncate_pagecache_range(VFS_I(ip), XFS_FSB_TO_B(mp, start_fsb),
                                         XFS_FSB_TO_B(mp, end_fsb) - 1);
 
@@ -1141,7 +1147,7 @@ xfs_file_iomap_end(
 {
        if ((flags & IOMAP_WRITE) && iomap->type == IOMAP_DELALLOC)
                return xfs_file_iomap_end_delalloc(XFS_I(inode), offset,
-                               length, written);
+                               length, written, iomap);
        return 0;
 }