[XFS] move xfs_bmbt_killroot to common code

xfs_bmbt_killroot is a mostly generic implementation of moving from a real
block based root to an inode based root. So move it to xfs_btree.c where
it can use all the nice infrastructure there and make it pointer size
agnostic

The new name for it is xfs_btree_kill_iroot, following the old naming but
making it clear we're dealing with the root in inode case here, and to
avoid confusion with xfs_btree_new_root which is used for the not inode
rooted case. I've also added a comment describing what it does and why
it's named the way it is.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32203a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>

1 files changed, 22 insertions, 94 deletions

diff --git a/fs/xfs/xfs_bmap_btree.c b/fs/xfs/xfs_bmap_btree.c
index 2b15df32b7d2..6b7774ebc26a 100644
--- a/fs/xfs/xfs_bmap_btree.c
+++ b/fs/xfs/xfs_bmap_btree.c
@@ -49,7 +49,6 @@
  */
 
 
-STATIC int xfs_bmbt_killroot(xfs_btree_cur_t *);
 STATIC void xfs_bmbt_log_keys(xfs_btree_cur_t *, xfs_buf_t *, int, int);
 STATIC void xfs_bmbt_log_ptrs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
 
@@ -194,7 +193,7 @@ xfs_bmbt_delrec(
         if (level == cur->bc_nlevels - 1) {
                 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
                         cur->bc_private.b.whichfork);
-                if ((error = xfs_bmbt_killroot(cur))) {
+                if ((error = xfs_btree_kill_iroot(cur))) {
                         XFS_BMBT_TRACE_CURSOR(cur, ERROR);
                         goto error0;
                 }
@@ -228,7 +227,7 @@ xfs_bmbt_delrec(
          */
         if (lbno == NULLFSBLOCK && rbno == NULLFSBLOCK &&
             level == cur->bc_nlevels - 2) {
-                if ((error = xfs_bmbt_killroot(cur))) {
+                if ((error = xfs_btree_kill_iroot(cur))) {
                         XFS_BMBT_TRACE_CURSOR(cur, ERROR);
                         goto error0;
                 }
@@ -456,97 +455,6 @@ error0:
         return error;
 }
 
-STATIC int
-xfs_bmbt_killroot(
-        xfs_btree_cur_t         *cur)
-{
-        xfs_bmbt_block_t        *block;
-        xfs_bmbt_block_t        *cblock;
-        xfs_buf_t               *cbp;
-        xfs_bmbt_key_t          *ckp;
-        xfs_bmbt_ptr_t          *cpp;
-#ifdef DEBUG
-        int                     error;
-#endif
-        int                     i;
-        xfs_bmbt_key_t          *kp;
-        xfs_inode_t             *ip;
-        xfs_ifork_t             *ifp;
-        int                     level;
-        xfs_bmbt_ptr_t          *pp;
-
-        XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
-        level = cur->bc_nlevels - 1;
-        ASSERT(level >= 1);
-        /*
-         * Don't deal with the root block needs to be a leaf case.
-         * We're just going to turn the thing back into extents anyway.
-         */
-        if (level == 1) {
-                XFS_BMBT_TRACE_CURSOR(cur, EXIT);
-                return 0;
-        }
-        block = xfs_bmbt_get_block(cur, level, &cbp);
-        /*
-         * Give up if the root has multiple children.
-         */
-        if (be16_to_cpu(block->bb_numrecs) != 1) {
-                XFS_BMBT_TRACE_CURSOR(cur, EXIT);
-                return 0;
-        }
-        /*
-         * Only do this if the next level will fit.
-         * Then the data must be copied up to the inode,
-         * instead of freeing the root you free the next level.
-         */
-        cbp = cur->bc_bufs[level - 1];
-        cblock = XFS_BUF_TO_BMBT_BLOCK(cbp);
-        if (be16_to_cpu(cblock->bb_numrecs) > XFS_BMAP_BLOCK_DMAXRECS(level, cur)) {
-                XFS_BMBT_TRACE_CURSOR(cur, EXIT);
-                return 0;
-        }
-        ASSERT(be64_to_cpu(cblock->bb_leftsib) == NULLDFSBNO);
-        ASSERT(be64_to_cpu(cblock->bb_rightsib) == NULLDFSBNO);
-        ip = cur->bc_private.b.ip;
-        ifp = XFS_IFORK_PTR(ip, cur->bc_private.b.whichfork);
-        ASSERT(XFS_BMAP_BLOCK_IMAXRECS(level, cur) ==
-               XFS_BMAP_BROOT_MAXRECS(ifp->if_broot_bytes));
-        i = (int)(be16_to_cpu(cblock->bb_numrecs) - XFS_BMAP_BLOCK_IMAXRECS(level, cur));
-        if (i) {
-                xfs_iroot_realloc(ip, i, cur->bc_private.b.whichfork);
-                block = ifp->if_broot;
-        }
-        be16_add_cpu(&block->bb_numrecs, i);
-        ASSERT(block->bb_numrecs == cblock->bb_numrecs);
-        kp = XFS_BMAP_KEY_IADDR(block, 1, cur);
-        ckp = XFS_BMAP_KEY_IADDR(cblock, 1, cur);
-        memcpy(kp, ckp, be16_to_cpu(block->bb_numrecs) * sizeof(*kp));
-        pp = XFS_BMAP_PTR_IADDR(block, 1, cur);
-        cpp = XFS_BMAP_PTR_IADDR(cblock, 1, cur);
-#ifdef DEBUG
-        for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
-                if ((error = xfs_btree_check_lptr_disk(cur, cpp[i], level - 1))) {
-                        XFS_BMBT_TRACE_CURSOR(cur, ERROR);
-                        return error;
-                }
-        }
-#endif
-        memcpy(pp, cpp, be16_to_cpu(block->bb_numrecs) * sizeof(*pp));
-        xfs_bmap_add_free(XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(cbp)), 1,
-                        cur->bc_private.b.flist, cur->bc_mp);
-        ip->i_d.di_nblocks--;
-        XFS_TRANS_MOD_DQUOT_BYINO(cur->bc_mp, cur->bc_tp, ip,
-                        XFS_TRANS_DQ_BCOUNT, -1L);
-        xfs_trans_binval(cur->bc_tp, cbp);
-        cur->bc_bufs[level - 1] = NULL;
-        be16_add_cpu(&block->bb_level, -1);
-        xfs_trans_log_inode(cur->bc_tp, ip,
-                XFS_ILOG_CORE | XFS_ILOG_FBROOT(cur->bc_private.b.whichfork));
-        cur->bc_nlevels--;
-        XFS_BMBT_TRACE_CURSOR(cur, EXIT);
-        return 0;
-}
-
 /*
  * Log key values from the btree block.
  */
@@ -1299,6 +1207,25 @@ xfs_bmbt_alloc_block(
 }
 
 STATIC int
+xfs_bmbt_free_block(
+        struct xfs_btree_cur    *cur,
+        struct xfs_buf          *bp)
+{
+        struct xfs_mount        *mp = cur->bc_mp;
+        struct xfs_inode        *ip = cur->bc_private.b.ip;
+        struct xfs_trans        *tp = cur->bc_tp;
+        xfs_fsblock_t           fsbno = XFS_DADDR_TO_FSB(mp, XFS_BUF_ADDR(bp));
+
+        xfs_bmap_add_free(fsbno, 1, cur->bc_private.b.flist, mp);
+        ip->i_d.di_nblocks--;
+
+        xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+        XFS_TRANS_MOD_DQUOT_BYINO(mp, tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
+        xfs_trans_binval(tp, bp);
+        return 0;
+}
+
+STATIC int
 xfs_bmbt_get_maxrecs(
         struct xfs_btree_cur    *cur,
         int                     level)
@@ -1460,6 +1387,7 @@ static const struct xfs_btree_ops xfs_bmbt_ops = {
         .dup_cursor             = xfs_bmbt_dup_cursor,
         .update_cursor          = xfs_bmbt_update_cursor,
         .alloc_block            = xfs_bmbt_alloc_block,
+        .free_block             = xfs_bmbt_free_block,
         .get_maxrecs            = xfs_bmbt_get_maxrecs,
         .get_dmaxrecs           = xfs_bmbt_get_dmaxrecs,
         .init_key_from_rec      = xfs_bmbt_init_key_from_rec,