xfs: fully initialise temp leaf in xfs_attr3_leaf_compact

[firefly-linux-kernel-4.4.55.git] / fs / xfs / xfs_attr_leaf.c

diff --git a/fs/xfs/xfs_attr_leaf.c b/fs/xfs/xfs_attr_leaf.c
index 79ece72976ae9adf50d025c02d0e1c66e4de80ee..5b03d15b707b59d07d083e04eceaebe08abb9a53 100644 (file)
--- a/fs/xfs/xfs_attr_leaf.c
+++ b/fs/xfs/xfs_attr_leaf.c
@@ -1445,11 +1445,12 @@ xfs_attr3_leaf_add_work(
 STATIC void
 xfs_attr3_leaf_compact(
        struct xfs_da_args      *args,
-       struct xfs_attr3_icleaf_hdr *ichdr_d,
+       struct xfs_attr3_icleaf_hdr *ichdr_dst,
        struct xfs_buf          *bp)
 {
-       xfs_attr_leafblock_t    *leaf_s, *leaf_d;
-       struct xfs_attr3_icleaf_hdr ichdr_s;
+       struct xfs_attr_leafblock *leaf_src;
+       struct xfs_attr_leafblock *leaf_dst;
+       struct xfs_attr3_icleaf_hdr ichdr_src;
        struct xfs_trans        *trans = args->trans;
        struct xfs_mount        *mp = trans->t_mountp;
        char                    *tmpbuffer;
@@ -1457,29 +1458,38 @@ xfs_attr3_leaf_compact(
        trace_xfs_attr_leaf_compact(args);
 
        tmpbuffer = kmem_alloc(XFS_LBSIZE(mp), KM_SLEEP);
-       ASSERT(tmpbuffer != NULL);
        memcpy(tmpbuffer, bp->b_addr, XFS_LBSIZE(mp));
        memset(bp->b_addr, 0, XFS_LBSIZE(mp));
+       leaf_src = (xfs_attr_leafblock_t *)tmpbuffer;
+       leaf_dst = bp->b_addr;
 
        /*
-        * Copy basic information
+        * Copy the on-disk header back into the destination buffer to ensure
+        * all the information in the header that is not part of the incore
+        * header structure is preserved.
         */
-       leaf_s = (xfs_attr_leafblock_t *)tmpbuffer;
-       leaf_d = bp->b_addr;
-       ichdr_s = *ichdr_d;     /* struct copy */
-       ichdr_d->firstused = XFS_LBSIZE(mp);
-       ichdr_d->usedbytes = 0;
-       ichdr_d->count = 0;
-       ichdr_d->holes = 0;
-       ichdr_d->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_s);
-       ichdr_d->freemap[0].size = ichdr_d->firstused - ichdr_d->freemap[0].base;
+       memcpy(bp->b_addr, tmpbuffer, xfs_attr3_leaf_hdr_size(leaf_src));
+
+       /* Initialise the incore headers */
+       ichdr_src = *ichdr_dst; /* struct copy */
+       ichdr_dst->firstused = XFS_LBSIZE(mp);
+       ichdr_dst->usedbytes = 0;
+       ichdr_dst->count = 0;
+       ichdr_dst->holes = 0;
+       ichdr_dst->freemap[0].base = xfs_attr3_leaf_hdr_size(leaf_src);
+       ichdr_dst->freemap[0].size = ichdr_dst->firstused -
+                                               ichdr_dst->freemap[0].base;
+
+
+       /* write the header back to initialise the underlying buffer */
+       xfs_attr3_leaf_hdr_to_disk(leaf_dst, ichdr_dst);
 
        /*
         * Copy all entry's in the same (sorted) order,
         * but allocate name/value pairs packed and in sequence.
         */
-       xfs_attr3_leaf_moveents(leaf_s, &ichdr_s, 0, leaf_d, ichdr_d, 0,
-                               ichdr_s.count, mp);
+       xfs_attr3_leaf_moveents(leaf_src, &ichdr_src, 0, leaf_dst, ichdr_dst, 0,
+                               ichdr_src.count, mp);
        /*
         * this logs the entire buffer, but the caller must write the header
         * back to the buffer when it is finished modifying it.