2 files changed, 56 insertions, 15 deletions

diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index 067a6abdeabe..5d2651f1c759 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -367,9 +367,12 @@ xfs_dir2_leaf_addname(
         /*
          * How many bytes do we need in the leaf block?
          */
-        needbytes =
-                (leaf->hdr.stale ? 0 : (uint)sizeof(leaf->ents[0])) +
-                (use_block != -1 ? 0 : (uint)sizeof(leaf->bests[0]));
+        needbytes = 0;
+        if (!leaf->hdr.stale)
+                needbytes += sizeof(xfs_dir2_leaf_entry_t);
+        if (use_block == -1)
+                needbytes += sizeof(xfs_dir2_data_off_t);
+
         /*
          * Now kill use_block if it refers to a missing block, so we
          * can use it as an indication of allocation needed.
@@ -1763,6 +1766,20 @@ xfs_dir2_leaf_trim_data(
         return 0;
 }
 
+static inline size_t
+xfs_dir2_leaf_size(
+        struct xfs_dir2_leaf_hdr        *hdr,
+        int                             counts)
+{
+        int                     entries;
+
+        entries = be16_to_cpu(hdr->count) - be16_to_cpu(hdr->stale);
+        return sizeof(xfs_dir2_leaf_hdr_t) +
+            entries * sizeof(xfs_dir2_leaf_entry_t) +
+            counts * sizeof(xfs_dir2_data_off_t) +
+            sizeof(xfs_dir2_leaf_tail_t);
+}
+
 /*
  * Convert node form directory to leaf form directory.
  * The root of the node form dir needs to already be a LEAFN block.
@@ -1844,18 +1861,17 @@ xfs_dir2_node_to_leaf(
         free = fbp->data;
         ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
         ASSERT(!free->hdr.firstdb);
+
         /*
          * Now see if the leafn and free data will fit in a leaf1.
          * If not, release the buffer and give up.
          */
-        if ((uint)sizeof(leaf->hdr) +
-            (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale)) * (uint)sizeof(leaf->ents[0]) +
-            be32_to_cpu(free->hdr.nvalid) * (uint)sizeof(leaf->bests[0]) +
-            (uint)sizeof(leaf->tail) >
-            mp->m_dirblksize) {
+        if (xfs_dir2_leaf_size(&leaf->hdr, be32_to_cpu(free->hdr.nvalid)) >
+                        mp->m_dirblksize) {
                 xfs_da_brelse(tp, fbp);
                 return 0;
         }
+
         /*
          * If the leaf has any stale entries in it, compress them out.
          * The compact routine will log the header.
@@ -1874,7 +1890,7 @@ xfs_dir2_node_to_leaf(
          * Set up the leaf bests table.
          */
         memcpy(xfs_dir2_leaf_bests_p(ltp), free->bests,
-                be32_to_cpu(ltp->bestcount) * sizeof(leaf->bests[0]));
+                be32_to_cpu(ltp->bestcount) * sizeof(xfs_dir2_data_off_t));
         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
         xfs_dir2_leaf_log_tail(tp, lbp);
         xfs_dir2_leaf_check(dp, lbp);
diff --git a/fs/xfs/xfs_dir2_leaf.h b/fs/xfs/xfs_dir2_leaf.h
index bc620622c342..140281adc7e5 100644
--- a/fs/xfs/xfs_dir2_leaf.h
+++ b/fs/xfs/xfs_dir2_leaf.h
@@ -18,6 +18,36 @@
 #ifndef __XFS_DIR2_LEAF_H__
 #define __XFS_DIR2_LEAF_H__
 
+/*
+ * Directory format 2, leaf block structures.
+ *
+ * A pure data block looks like the following drawing on disk:
+ *
+ *    +---------------------------+
+ *    | xfs_dir2_leaf_hdr_t       |
+ *    +---------------------------+
+ *    | xfs_dir2_leaf_entry_t     |
+ *    | xfs_dir2_leaf_entry_t     |
+ *    | xfs_dir2_leaf_entry_t     |
+ *    | xfs_dir2_leaf_entry_t     |
+ *    | ...                       |
+ *    +---------------------------+
+ *    | xfs_dir2_data_off_t       |
+ *    | xfs_dir2_data_off_t       |
+ *    | xfs_dir2_data_off_t       |
+ *    | ...                       |
+ *    +---------------------------+
+ *    | xfs_dir2_leaf_tail_t      |
+ *    +---------------------------+
+ *
+ * The bests (xfs_dir2_data_off_t members) and tail are at the end of the
+ * block for single-leaf only (magic = XFS_DIR2_LEAF1_MAGIC not
+ * XFS_DIR2_LEAFN_MAGIC).
+ *
+ * As all the entries are variable size structures the accessors in this
+ * file should be used to iterate over them.
+ */
+
 struct uio;
 struct xfs_dabuf;
 struct xfs_da_args;
@@ -67,15 +97,10 @@ typedef struct xfs_dir2_leaf_tail {
 
 /*
  * Leaf block.
- * bests and tail are at the end of the block for single-leaf only
- * (magic = XFS_DIR2_LEAF1_MAGIC not XFS_DIR2_LEAFN_MAGIC).
  */
 typedef struct xfs_dir2_leaf {
         xfs_dir2_leaf_hdr_t     hdr;            /* leaf header */
-        xfs_dir2_leaf_entry_t   ents[1];        /* entries */
-                                                /* ... */
-        xfs_dir2_data_off_t     bests[1];       /* best free counts */
-        xfs_dir2_leaf_tail_t    tail;           /* leaf tail */
+        xfs_dir2_leaf_entry_t   ents[]; /* entries */
 } xfs_dir2_leaf_t;
 
 /*