xfs: remove unused calculation in xfs_dir2_sf_addname()

The "add_entsize" calculated here is never used.
"incr_isize" accounts for the inode expansion of the
old entries + parent + new entry all by itself.

Once we've removed add_entsize there, it's just a pointless
intermediate variable elsewhere, so remove it.
For that matter, old_isize is gratuitous too, so nuke that.

And add a few comments so the magic "+1's" and "+2's" make
a bit more sense.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_dir2_sf.c b/fs/xfs/xfs_dir2_sf.c
index 3725fb1..7aab8ec 100644 (file)
--- a/fs/xfs/xfs_dir2_sf.c
+++ b/fs/xfs/xfs_dir2_sf.c
@@ -285,14 +285,12 @@ int                                               /* error */
 xfs_dir2_sf_addname(
        xfs_da_args_t           *args)          /* operation arguments */
 {
-       int                     add_entsize;    /* size of the new entry */
        xfs_inode_t             *dp;            /* incore directory inode */
        int                     error;          /* error return value */
        int                     incr_isize;     /* total change in size */
        int                     new_isize;      /* di_size after adding name */
        int                     objchange;      /* changing to 8-byte inodes */
        xfs_dir2_data_aoff_t    offset = 0;     /* offset for new entry */
-       int                     old_isize;      /* di_size before adding name */
        int                     pick;           /* which algorithm to use */
        xfs_dir2_sf_hdr_t       *sfp;           /* shortform structure */
        xfs_dir2_sf_entry_t     *sfep = NULL;   /* shortform entry */
@@ -316,8 +314,7 @@ xfs_dir2_sf_addname(
        /*
         * Compute entry (and change in) size.
         */
-       add_entsize = dp->d_ops->sf_entsize(sfp, args->namelen);
-       incr_isize = add_entsize;
+       incr_isize = dp->d_ops->sf_entsize(sfp, args->namelen);
        objchange = 0;
 #if XFS_BIG_INUMS
        /*
@@ -325,11 +322,8 @@ xfs_dir2_sf_addname(
         */
        if (args->inumber > XFS_DIR2_MAX_SHORT_INUM && sfp->i8count == 0) {
                /*
-                * Yes, adjust the entry size and the total size.
+                * Yes, adjust the inode size.  old count + (parent + new)
                 */
-               add_entsize +=
-                       (uint)sizeof(xfs_dir2_ino8_t) -
-                       (uint)sizeof(xfs_dir2_ino4_t);
                incr_isize +=
                        (sfp->count + 2) *
                        ((uint)sizeof(xfs_dir2_ino8_t) -
@@ -337,8 +331,7 @@ xfs_dir2_sf_addname(
                objchange = 1;
        }
 #endif
-       old_isize = (int)dp->i_d.di_size;
-       new_isize = old_isize + incr_isize;
+       new_isize = (int)dp->i_d.di_size + incr_isize;
        /*
         * Won't fit as shortform any more (due to size),
         * or the pick routine says it won't (due to offset values).
@@ -1110,9 +1103,9 @@ xfs_dir2_sf_toino4(
 }
 
 /*
- * Convert from 4-byte inode numbers to 8-byte inode numbers.
- * The new 8-byte inode number is not there yet, we leave with the
- * count 1 but no corresponding entry.
+ * Convert existing entries from 4-byte inode numbers to 8-byte inode numbers.
+ * The new entry w/ an 8-byte inode number is not there yet; we leave with
+ * i8count set to 1, but no corresponding 8-byte entry.
  */
 static void
 xfs_dir2_sf_toino8(
@@ -1145,7 +1138,7 @@ xfs_dir2_sf_toino8(
        ASSERT(oldsfp->i8count == 0);
        memcpy(buf, oldsfp, oldsize);
        /*
-        * Compute the new inode size.
+        * Compute the new inode size (nb: entry count + 1 for parent)
         */
        newsize =
                oldsize +