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/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c
index 35ea6642d969fc962dc23d6fa29a187cd36e240f..435ccb2496ccdf55fbec601fa7473f8b09cc35a4 100644 (file)
--- a/fs/xfs/libxfs/xfs_inode_fork.c
+++ b/fs/xfs/libxfs/xfs_inode_fork.c
@@ -211,9 +211,7 @@ xfs_iformat_btree(
                return -EFSCORRUPTED;
        }
 
-       ifp->if_broot_bytes = size;
-       ifp->if_broot = kmalloc(size,
-                               GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
+       xfs_iroot_alloc(ip, whichfork, size);
        ASSERT(ifp->if_broot != NULL);
        /*
         * Copy and convert from the on-disk structure
@@ -362,6 +360,33 @@ 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 = kmalloc(bytes,
+                       GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
+       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;
+       kfree(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
@@ -410,9 +435,7 @@ xfs_iroot_realloc(
                 */
                if (ifp->if_broot_bytes == 0) {
                        new_size = xfs_bmap_broot_space_calc(mp, rec_diff);
-                       ifp->if_broot = kmalloc(new_size,
-                                               GFP_KERNEL | __GFP_NOFAIL);
-                       ifp->if_broot_bytes = (int)new_size;
+                       xfs_iroot_alloc(ip, whichfork, new_size);
                        return;
                }
 
@@ -451,17 +474,16 @@ xfs_iroot_realloc(
                new_size = xfs_bmap_broot_space_calc(mp, new_max);
        else
                new_size = 0;
-       if (new_size > 0) {
-               new_broot = kmalloc(new_size, GFP_KERNEL | __GFP_NOFAIL);
-               /*
-                * 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 = kmalloc(new_size,
+                       GFP_KERNEL | __GFP_NOLOCKDEP | __GFP_NOFAIL);
+       memcpy(new_broot, ifp->if_broot, xfs_bmbt_block_len(ip->i_mount));
+
        /*
         * Only copy the records and pointers if there are any.
         */
@@ -485,9 +507,8 @@ xfs_iroot_realloc(
        kfree(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/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h
index 2373d12fd474f0cc4f8227a038a554649f580ee7..3f228a00b67ddf667c24805b6cab4bead31dda6d 100644 (file)
--- a/fs/xfs/libxfs/xfs_inode_fork.h
+++ b/fs/xfs/libxfs/xfs_inode_fork.h
@@ -170,6 +170,9 @@ 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 *,