xfs: vectorise encoding/decoding directory headers

Conversion from on-disk structures to in-core header structures
currently relies on magic number checks. If the magic number is
wrong, but one of the supported values, we do the wrong thing with
the encode/decode operation. Split these functions so that there are
discrete operations for the specific directory format we are
handling.

In doing this, move all the header encode/decode functions to
xfs_da_format.c as they are directly manipulating the on-disk
format. It should be noted that all the growth in binary size is
from xfs_da_format.c - the rest of the code actaully shrinks.

   text    data     bss     dec     hex filename
 794490   96802    1096  892388   d9de4 fs/xfs/xfs.o.orig
 792986   96802    1096  890884   d9804 fs/xfs/xfs.o.p1
 792350   96802    1096  890248   d9588 fs/xfs/xfs.o.p2
 789293   96802    1096  887191   d8997 fs/xfs/xfs.o.p3
 789005   96802    1096  886903   d8997 fs/xfs/xfs.o.p4
 789061   96802    1096  886959   d88af fs/xfs/xfs.o.p5
 789733   96802    1096  887631   d8b4f fs/xfs/xfs.o.p6
 791421   96802    1096  889319   d91e7 fs/xfs/xfs.o.p7

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 49 insertions, 92 deletions

diff --git a/fs/xfs/xfs_da_btree.c b/fs/xfs/xfs_da_btree.c
index 26dfc42a28f9..a51762dae543 100644
--- a/fs/xfs/xfs_da_btree.c
+++ b/fs/xfs/xfs_da_btree.c
@@ -129,56 +129,6 @@ xfs_da_state_free(xfs_da_state_t *state)
         kmem_zone_free(xfs_da_state_zone, state);
 }
 
-void
-xfs_da3_node_hdr_from_disk(
-        struct xfs_da3_icnode_hdr       *to,
-        struct xfs_da_intnode           *from)
-{
-        ASSERT(from->hdr.info.magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
-               from->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC));
-
-        if (from->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
-                struct xfs_da3_node_hdr *hdr3 = (struct xfs_da3_node_hdr *)from;
-
-                to->forw = be32_to_cpu(hdr3->info.hdr.forw);
-                to->back = be32_to_cpu(hdr3->info.hdr.back);
-                to->magic = be16_to_cpu(hdr3->info.hdr.magic);
-                to->count = be16_to_cpu(hdr3->__count);
-                to->level = be16_to_cpu(hdr3->__level);
-                return;
-        }
-        to->forw = be32_to_cpu(from->hdr.info.forw);
-        to->back = be32_to_cpu(from->hdr.info.back);
-        to->magic = be16_to_cpu(from->hdr.info.magic);
-        to->count = be16_to_cpu(from->hdr.__count);
-        to->level = be16_to_cpu(from->hdr.__level);
-}
-
-void
-xfs_da3_node_hdr_to_disk(
-        struct xfs_da_intnode           *to,
-        struct xfs_da3_icnode_hdr       *from)
-{
-        ASSERT(from->magic == XFS_DA_NODE_MAGIC ||
-               from->magic == XFS_DA3_NODE_MAGIC);
-
-        if (from->magic == XFS_DA3_NODE_MAGIC) {
-                struct xfs_da3_node_hdr *hdr3 = (struct xfs_da3_node_hdr *)to;
-
-                hdr3->info.hdr.forw = cpu_to_be32(from->forw);
-                hdr3->info.hdr.back = cpu_to_be32(from->back);
-                hdr3->info.hdr.magic = cpu_to_be16(from->magic);
-                hdr3->__count = cpu_to_be16(from->count);
-                hdr3->__level = cpu_to_be16(from->level);
-                return;
-        }
-        to->hdr.info.forw = cpu_to_be32(from->forw);
-        to->hdr.info.back = cpu_to_be32(from->back);
-        to->hdr.info.magic = cpu_to_be16(from->magic);
-        to->hdr.__count = cpu_to_be16(from->count);
-        to->hdr.__level = cpu_to_be16(from->level);
-}
-
 static bool
 xfs_da3_node_verify(
         struct xfs_buf          *bp)
@@ -186,8 +136,11 @@ xfs_da3_node_verify(
         struct xfs_mount        *mp = bp->b_target->bt_mount;
         struct xfs_da_intnode   *hdr = bp->b_addr;
         struct xfs_da3_icnode_hdr ichdr;
+        const struct xfs_dir_ops *ops;
+
+        ops = xfs_dir_get_ops(mp, NULL);
 
-        xfs_da3_node_hdr_from_disk(&ichdr, hdr);
+        ops->node_hdr_from_disk(&ichdr, hdr);
 
         if (xfs_sb_version_hascrc(&mp->m_sb)) {
                 struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
@@ -354,11 +307,12 @@ xfs_da3_node_create(
         struct xfs_da3_icnode_hdr ichdr = {0};
         struct xfs_buf          *bp;
         int                     error;
+        struct xfs_inode        *dp = args->dp;
 
         trace_xfs_da_node_create(args);
         ASSERT(level <= XFS_DA_NODE_MAXDEPTH);
 
-        error = xfs_da_get_buf(tp, args->dp, blkno, -1, &bp, whichfork);
+        error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, whichfork);
         if (error)
                 return(error);
         bp->b_ops = &xfs_da3_node_buf_ops;
@@ -377,10 +331,10 @@ xfs_da3_node_create(
         }
         ichdr.level = level;
 
-        xfs_da3_node_hdr_to_disk(node, &ichdr);
+        dp->d_ops->node_hdr_to_disk(node, &ichdr);
         xfs_trans_log_buf(tp, bp,
                 XFS_DA_LOGRANGE(node, &node->hdr,
-                                args->dp->d_ops->node_hdr_size()));
+                                dp->d_ops->node_hdr_size()));
 
         *bpp = bp;
         return(0);
@@ -590,7 +544,7 @@ xfs_da3_root_split(
             oldroot->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
                 struct xfs_da3_icnode_hdr nodehdr;
 
-                xfs_da3_node_hdr_from_disk(&nodehdr, oldroot);
+                dp->d_ops->node_hdr_from_disk(&nodehdr, oldroot);
                 btree = dp->d_ops->node_tree_p(oldroot);
                 size = (int)((char *)&btree[nodehdr.count] - (char *)oldroot);
                 level = nodehdr.level;
@@ -605,7 +559,7 @@ xfs_da3_root_split(
                 struct xfs_dir2_leaf_entry *ents;
 
                 leaf = (xfs_dir2_leaf_t *)oldroot;
-                xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
+                dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
                 ents = dp->d_ops->leaf_ents_p(leaf);
 
                 ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
@@ -650,14 +604,14 @@ xfs_da3_root_split(
                 return error;
 
         node = bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
         btree = dp->d_ops->node_tree_p(node);
         btree[0].hashval = cpu_to_be32(blk1->hashval);
         btree[0].before = cpu_to_be32(blk1->blkno);
         btree[1].hashval = cpu_to_be32(blk2->hashval);
         btree[1].before = cpu_to_be32(blk2->blkno);
         nodehdr.count = 2;
-        xfs_da3_node_hdr_to_disk(node, &nodehdr);
+        dp->d_ops->node_hdr_to_disk(node, &nodehdr);
 
 #ifdef DEBUG
         if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
@@ -694,11 +648,12 @@ xfs_da3_node_split(
         int                     newcount;
         int                     error;
         int                     useextra;
+        struct xfs_inode        *dp = state->args->dp;
 
         trace_xfs_da_node_split(state->args);
 
         node = oldblk->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
 
         /*
          * With V2 dirs the extra block is data or freespace.
@@ -745,7 +700,7 @@ xfs_da3_node_split(
          * If we had double-split op below us, then add the extra block too.
          */
         node = oldblk->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
         if (oldblk->index <= nodehdr.count) {
                 oldblk->index++;
                 xfs_da3_node_add(state, oldblk, addblk);
@@ -800,8 +755,8 @@ xfs_da3_node_rebalance(
 
         node1 = blk1->bp->b_addr;
         node2 = blk2->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr1, node1);
-        xfs_da3_node_hdr_from_disk(&nodehdr2, node2);
+        dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
+        dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
         btree1 = dp->d_ops->node_tree_p(node1);
         btree2 = dp->d_ops->node_tree_p(node2);
 
@@ -816,8 +771,8 @@ xfs_da3_node_rebalance(
                 tmpnode = node1;
                 node1 = node2;
                 node2 = tmpnode;
-                xfs_da3_node_hdr_from_disk(&nodehdr1, node1);
-                xfs_da3_node_hdr_from_disk(&nodehdr2, node2);
+                dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
+                dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
                 btree1 = dp->d_ops->node_tree_p(node1);
                 btree2 = dp->d_ops->node_tree_p(node2);
                 swap = 1;
@@ -881,12 +836,12 @@ xfs_da3_node_rebalance(
         /*
          * Log header of node 1 and all current bits of node 2.
          */
-        xfs_da3_node_hdr_to_disk(node1, &nodehdr1);
+        dp->d_ops->node_hdr_to_disk(node1, &nodehdr1);
         xfs_trans_log_buf(tp, blk1->bp,
                 XFS_DA_LOGRANGE(node1, &node1->hdr,
                                 dp->d_ops->node_hdr_size()));
 
-        xfs_da3_node_hdr_to_disk(node2, &nodehdr2);
+        dp->d_ops->node_hdr_to_disk(node2, &nodehdr2);
         xfs_trans_log_buf(tp, blk2->bp,
                 XFS_DA_LOGRANGE(node2, &node2->hdr,
                                 dp->d_ops->node_hdr_size() +
@@ -899,8 +854,8 @@ xfs_da3_node_rebalance(
         if (swap) {
                 node1 = blk1->bp->b_addr;
                 node2 = blk2->bp->b_addr;
-                xfs_da3_node_hdr_from_disk(&nodehdr1, node1);
-                xfs_da3_node_hdr_from_disk(&nodehdr2, node2);
+                dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
+                dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
                 btree1 = dp->d_ops->node_tree_p(node1);
                 btree2 = dp->d_ops->node_tree_p(node2);
         }
@@ -934,7 +889,7 @@ xfs_da3_node_add(
         trace_xfs_da_node_add(state->args);
 
         node = oldblk->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
         btree = dp->d_ops->node_tree_p(node);
 
         ASSERT(oldblk->index >= 0 && oldblk->index <= nodehdr.count);
@@ -958,7 +913,7 @@ xfs_da3_node_add(
                                 tmp + sizeof(*btree)));
 
         nodehdr.count += 1;
-        xfs_da3_node_hdr_to_disk(node, &nodehdr);
+        dp->d_ops->node_hdr_to_disk(node, &nodehdr);
         xfs_trans_log_buf(state->args->trans, oldblk->bp,
                 XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size()));
 
@@ -1097,6 +1052,7 @@ xfs_da3_root_join(
         struct xfs_da3_icnode_hdr oldroothdr;
         struct xfs_da_node_entry *btree;
         int                     error;
+        struct xfs_inode        *dp = state->args->dp;
 
         trace_xfs_da_root_join(state->args);
 
@@ -1104,7 +1060,7 @@ xfs_da3_root_join(
 
         args = state->args;
         oldroot = root_blk->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&oldroothdr, oldroot);
+        dp->d_ops->node_hdr_from_disk(&oldroothdr, oldroot);
         ASSERT(oldroothdr.forw == 0);
         ASSERT(oldroothdr.back == 0);
 
@@ -1118,10 +1074,10 @@ xfs_da3_root_join(
          * Read in the (only) child block, then copy those bytes into
          * the root block's buffer and free the original child block.
          */
-        btree = args->dp->d_ops->node_tree_p(oldroot);
+        btree = dp->d_ops->node_tree_p(oldroot);
         child = be32_to_cpu(btree[0].before);
         ASSERT(child != 0);
-        error = xfs_da3_node_read(args->trans, args->dp, child, -1, &bp,
+        error = xfs_da3_node_read(args->trans, dp, child, -1, &bp,
                                              args->whichfork);
         if (error)
                 return error;
@@ -1171,6 +1127,7 @@ xfs_da3_node_toosmall(
         int                     error;
         int                     retval;
         int                     i;
+        struct xfs_inode        *dp = state->args->dp;
 
         trace_xfs_da_node_toosmall(state->args);
 
@@ -1182,7 +1139,7 @@ xfs_da3_node_toosmall(
         blk = &state->path.blk[ state->path.active-1 ];
         info = blk->bp->b_addr;
         node = (xfs_da_intnode_t *)info;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
         if (nodehdr.count > (state->node_ents >> 1)) {
                 *action = 0;    /* blk over 50%, don't try to join */
                 return(0);      /* blk over 50%, don't try to join */
@@ -1234,13 +1191,13 @@ xfs_da3_node_toosmall(
                         blkno = nodehdr.back;
                 if (blkno == 0)
                         continue;
-                error = xfs_da3_node_read(state->args->trans, state->args->dp,
+                error = xfs_da3_node_read(state->args->trans, dp,
                                         blkno, -1, &bp, state->args->whichfork);
                 if (error)
                         return(error);
 
                 node = bp->b_addr;
-                xfs_da3_node_hdr_from_disk(&thdr, node);
+                dp->d_ops->node_hdr_from_disk(&thdr, node);
                 xfs_trans_brelse(state->args->trans, bp);
 
                 if (count - thdr.count >= 0)
@@ -1287,7 +1244,7 @@ xfs_da3_node_lasthash(
         struct xfs_da3_icnode_hdr nodehdr;
 
         node = bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
         if (count)
                 *count = nodehdr.count;
         if (!nodehdr.count)
@@ -1338,7 +1295,7 @@ xfs_da3_fixhashpath(
                 struct xfs_da3_icnode_hdr nodehdr;
 
                 node = blk->bp->b_addr;
-                xfs_da3_node_hdr_from_disk(&nodehdr, node);
+                dp->d_ops->node_hdr_from_disk(&nodehdr, node);
                 btree = dp->d_ops->node_tree_p(node);
                 if (be32_to_cpu(btree->hashval) == lasthash)
                         break;
@@ -1370,7 +1327,7 @@ xfs_da3_node_remove(
         trace_xfs_da_node_remove(state->args);
 
         node = drop_blk->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
         ASSERT(drop_blk->index < nodehdr.count);
         ASSERT(drop_blk->index >= 0);
 
@@ -1391,7 +1348,7 @@ xfs_da3_node_remove(
         xfs_trans_log_buf(state->args->trans, drop_blk->bp,
             XFS_DA_LOGRANGE(node, &btree[index], sizeof(btree[index])));
         nodehdr.count -= 1;
-        xfs_da3_node_hdr_to_disk(node, &nodehdr);
+        dp->d_ops->node_hdr_to_disk(node, &nodehdr);
         xfs_trans_log_buf(state->args->trans, drop_blk->bp,
             XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size()));
 
@@ -1426,8 +1383,8 @@ xfs_da3_node_unbalance(
 
         drop_node = drop_blk->bp->b_addr;
         save_node = save_blk->bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&drop_hdr, drop_node);
-        xfs_da3_node_hdr_from_disk(&save_hdr, save_node);
+        dp->d_ops->node_hdr_from_disk(&drop_hdr, drop_node);
+        dp->d_ops->node_hdr_from_disk(&save_hdr, save_node);
         drop_btree = dp->d_ops->node_tree_p(drop_node);
         save_btree = dp->d_ops->node_tree_p(save_node);
         tp = state->args->trans;
@@ -1463,7 +1420,7 @@ xfs_da3_node_unbalance(
         memcpy(&save_btree[sindex], &drop_btree[0], tmp);
         save_hdr.count += drop_hdr.count;
 
-        xfs_da3_node_hdr_to_disk(save_node, &save_hdr);
+        dp->d_ops->node_hdr_to_disk(save_node, &save_hdr);
         xfs_trans_log_buf(tp, save_blk->bp,
                 XFS_DA_LOGRANGE(save_node, &save_node->hdr,
                                 dp->d_ops->node_hdr_size()));
@@ -1556,7 +1513,7 @@ xfs_da3_node_lookup_int(
                  * Search an intermediate node for a match.
                  */
                 node = blk->bp->b_addr;
-                xfs_da3_node_hdr_from_disk(&nodehdr, node);
+                dp->d_ops->node_hdr_from_disk(&nodehdr, node);
                 btree = dp->d_ops->node_tree_p(node);
 
                 max = nodehdr.count;
@@ -1665,8 +1622,8 @@ xfs_da3_node_order(
 
         node1 = node1_bp->b_addr;
         node2 = node2_bp->b_addr;
-        xfs_da3_node_hdr_from_disk(&node1hdr, node1);
-        xfs_da3_node_hdr_from_disk(&node2hdr, node2);
+        dp->d_ops->node_hdr_from_disk(&node1hdr, node1);
+        dp->d_ops->node_hdr_from_disk(&node2hdr, node2);
         btree1 = dp->d_ops->node_tree_p(node1);
         btree2 = dp->d_ops->node_tree_p(node2);
 
@@ -1888,7 +1845,7 @@ xfs_da3_path_shift(
         level = (path->active-1) - 1;   /* skip bottom layer in path */
         for (blk = &path->blk[level]; level >= 0; blk--, level--) {
                 node = blk->bp->b_addr;
-                xfs_da3_node_hdr_from_disk(&nodehdr, node);
+                dp->d_ops->node_hdr_from_disk(&nodehdr, node);
                 btree = dp->d_ops->node_tree_p(node);
 
                 if (forward && (blk->index < nodehdr.count - 1)) {
@@ -1945,7 +1902,7 @@ xfs_da3_path_shift(
                 case XFS_DA3_NODE_MAGIC:
                         blk->magic = XFS_DA_NODE_MAGIC;
                         node = (xfs_da_intnode_t *)info;
-                        xfs_da3_node_hdr_from_disk(&nodehdr, node);
+                        dp->d_ops->node_hdr_from_disk(&nodehdr, node);
                         btree = dp->d_ops->node_tree_p(node);
                         blk->hashval = be32_to_cpu(btree[nodehdr.count - 1].hashval);
                         if (forward)
@@ -2233,7 +2190,7 @@ xfs_da3_swap_lastblock(
                 struct xfs_dir2_leaf_entry *ents;
 
                 dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
-                xfs_dir3_leaf_hdr_from_disk(&leafhdr, dead_leaf2);
+                dp->d_ops->leaf_hdr_from_disk(&leafhdr, dead_leaf2);
                 ents = dp->d_ops->leaf_ents_p(dead_leaf2);
                 dead_level = 0;
                 dead_hash = be32_to_cpu(ents[leafhdr.count - 1].hashval);
@@ -2241,7 +2198,7 @@ xfs_da3_swap_lastblock(
                 struct xfs_da3_icnode_hdr deadhdr;
 
                 dead_node = (xfs_da_intnode_t *)dead_info;
-                xfs_da3_node_hdr_from_disk(&deadhdr, dead_node);
+                dp->d_ops->node_hdr_from_disk(&deadhdr, dead_node);
                 btree = dp->d_ops->node_tree_p(dead_node);
                 dead_level = deadhdr.level;
                 dead_hash = be32_to_cpu(btree[deadhdr.count - 1].hashval);
@@ -2301,7 +2258,7 @@ xfs_da3_swap_lastblock(
                 if (error)
                         goto done;
                 par_node = par_buf->b_addr;
-                xfs_da3_node_hdr_from_disk(&par_hdr, par_node);
+                dp->d_ops->node_hdr_from_disk(&par_hdr, par_node);
                 if (level >= 0 && level != par_hdr.level + 1) {
                         XFS_ERROR_REPORT("xfs_da_swap_lastblock(4)",
                                          XFS_ERRLEVEL_LOW, mp);
@@ -2352,7 +2309,7 @@ xfs_da3_swap_lastblock(
                 if (error)
                         goto done;
                 par_node = par_buf->b_addr;
-                xfs_da3_node_hdr_from_disk(&par_hdr, par_node);
+                dp->d_ops->node_hdr_from_disk(&par_hdr, par_node);
                 if (par_hdr.level != level) {
                         XFS_ERROR_REPORT("xfs_da_swap_lastblock(7)",
                                          XFS_ERRLEVEL_LOW, mp);