xfs: refactor the allocation and freeing of incore inode fork btree roots

Refactor the code that allocates and freese the incore inode fork btree
roots.  This will help us disentangle some of the weird logic when we're
creating and tearing down inode-based btrees.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

diff --git a/libxfs/xfs_inode_fork.c b/libxfs/xfs_inode_fork.c
index 6359d2ec14582a283c3e395c43fdd406e741e6af..05a87f512de3e5fda76eb874393fa3b30d6d7440 100644 (file)
--- a/libxfs/xfs_inode_fork.c
+++ b/libxfs/xfs_inode_fork.c
@@ -205,8 +205,7 @@ xfs_iformat_btree(
                return -EFSCORRUPTED;
        }
 
-       ifp->if_broot_bytes = size;
-       ifp->if_broot = kmem_alloc(size, KM_NOFS);
+       xfs_iroot_alloc(ip, whichfork, size);
        ASSERT(ifp->if_broot != NULL);
        /*
         * Copy and convert from the on-disk structure
@@ -356,6 +355,32 @@ xfs_iformat_attr_fork(
        return error;
 }
 
+/* Allocate a new incore ifork btree root. */
+void
+xfs_iroot_alloc(
+       struct xfs_inode        *ip,
+       int                     whichfork,
+       size_t                  bytes)
+{
+       struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
+
+       ifp->if_broot = kmem_alloc(bytes, KM_NOFS);
+       ifp->if_broot_bytes = bytes;
+}
+
+/* Free all the memory and state associated with an incore ifork btree root. */
+void
+xfs_iroot_free(
+       struct xfs_inode        *ip,
+       int                     whichfork)
+{
+       struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
+
+       ifp->if_broot_bytes = 0;
+       kmem_free(ifp->if_broot);
+       ifp->if_broot = NULL;
+}
+
 /*
  * Reallocate the space for if_broot based on the number of records
  * being added or deleted as indicated in rec_diff.  Move the records
@@ -404,8 +429,7 @@ xfs_iroot_realloc(
                 */
                if (ifp->if_broot_bytes == 0) {
                        new_size = xfs_bmap_broot_space_calc(mp, rec_diff);
-                       ifp->if_broot = kmem_alloc(new_size, KM_NOFS);
-                       ifp->if_broot_bytes = (int)new_size;
+                       xfs_iroot_alloc(ip, whichfork, new_size);
                        return;
                }
 
@@ -444,17 +468,15 @@ xfs_iroot_realloc(
                new_size = xfs_bmap_broot_space_calc(mp, new_max);
        else
                new_size = 0;
-       if (new_size > 0) {
-               new_broot = kmem_alloc(new_size, KM_NOFS);
-               /*
-                * First copy over the btree block header.
-                */
-               memcpy(new_broot, ifp->if_broot,
-                       xfs_bmbt_block_len(ip->i_mount));
-       } else {
-               new_broot = NULL;
+       if (new_size == 0) {
+               xfs_iroot_free(ip, whichfork);
+               return;
        }
 
+       /* First copy over the btree block header. */
+       new_broot = kmem_alloc(new_size, KM_NOFS);
+       memcpy(new_broot, ifp->if_broot, xfs_bmbt_block_len(ip->i_mount));
+
        /*
         * Only copy the records and pointers if there are any.
         */
@@ -478,9 +500,8 @@ xfs_iroot_realloc(
        kmem_free(ifp->if_broot);
        ifp->if_broot = new_broot;
        ifp->if_broot_bytes = (int)new_size;
-       if (ifp->if_broot)
-               ASSERT(xfs_bmap_bmdr_space(ifp->if_broot) <=
-                       xfs_inode_fork_size(ip, whichfork));
+       ASSERT(xfs_bmap_bmdr_space(ifp->if_broot) <=
+               xfs_inode_fork_size(ip, whichfork));
        return;
 }
 

diff --git a/libxfs/xfs_inode_fork.h b/libxfs/xfs_inode_fork.h
index ebeb925be09d9c420cf9d3d6a3d2c4eb13df324f..18ea2d27777a2749e0496e1895ec2409017c93d8 100644 (file)
--- a/libxfs/xfs_inode_fork.h
+++ b/libxfs/xfs_inode_fork.h
@@ -172,6 +172,9 @@ void                xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
 void           xfs_idestroy_fork(struct xfs_ifork *ifp);
 void           xfs_idata_realloc(struct xfs_inode *ip, int64_t byte_diff,
                                int whichfork);
+void           xfs_iroot_alloc(struct xfs_inode *ip, int whichfork,
+                               size_t bytes);
+void           xfs_iroot_free(struct xfs_inode *ip, int whichfork);
 void           xfs_iroot_realloc(struct xfs_inode *, int, int);
 int            xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
 int            xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,