From: Darrick J. Wong <djwong@xxxxxxxxxx> Tidy up this function a bit before we start refactoring the memory handling and move the function to the bmbt code. Signed-off-by: "Darrick J. Wong" <djwong@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> --- fs/xfs/libxfs/xfs_inode_fork.c | 83 +++++++++++++++++++--------------------- 1 file changed, 40 insertions(+), 43 deletions(-) diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c index 1158ca48626b71..7f865479c4159f 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.c +++ b/fs/xfs/libxfs/xfs_inode_fork.c @@ -382,33 +382,32 @@ xfs_iformat_attr_fork( */ void xfs_iroot_realloc( - xfs_inode_t *ip, + struct xfs_inode *ip, int rec_diff, int whichfork) { struct xfs_mount *mp = ip->i_mount; - int cur_max; - struct xfs_ifork *ifp; + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); struct xfs_btree_block *new_broot; - int new_max; - size_t new_size; char *np; char *op; + size_t new_size; + short old_size = ifp->if_broot_bytes; + int cur_max; + int new_max; /* * Handle the degenerate case quietly. */ - if (rec_diff == 0) { + if (rec_diff == 0) return; - } - ifp = xfs_ifork_ptr(ip, whichfork); if (rec_diff > 0) { /* * If there wasn't any memory allocated before, just * allocate it now and get out. */ - if (ifp->if_broot_bytes == 0) { + if (old_size == 0) { new_size = xfs_bmap_broot_space_calc(mp, rec_diff); ifp->if_broot = kmalloc(new_size, GFP_KERNEL | __GFP_NOFAIL); @@ -422,13 +421,13 @@ xfs_iroot_realloc( * location. The records don't change location because * they are kept butted up against the btree block header. */ - cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, false); + cur_max = xfs_bmbt_maxrecs(mp, old_size, false); new_max = cur_max + rec_diff; new_size = xfs_bmap_broot_space_calc(mp, new_max); ifp->if_broot = krealloc(ifp->if_broot, new_size, GFP_KERNEL | __GFP_NOFAIL); op = (char *)xfs_bmap_broot_ptr_addr(mp, ifp->if_broot, 1, - ifp->if_broot_bytes); + old_size); np = (char *)xfs_bmap_broot_ptr_addr(mp, ifp->if_broot, 1, (int)new_size); ifp->if_broot_bytes = (int)new_size; @@ -443,52 +442,50 @@ xfs_iroot_realloc( * if_broot buffer. It must already exist. If we go to zero * records, just get rid of the root and clear the status bit. */ - ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0)); - cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, false); + ASSERT(ifp->if_broot != NULL && old_size > 0); + cur_max = xfs_bmbt_maxrecs(mp, old_size, false); new_max = cur_max + rec_diff; ASSERT(new_max >= 0); if (new_max > 0) 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) { + ifp->if_broot = NULL; + ifp->if_broot_bytes = 0; + return; } /* - * Only copy the keys and pointers if there are any. + * Shrink the btree root by allocating a smaller object and copying the + * fields from the old object to the new object. krealloc does nothing + * if we realloc downwards. */ - if (new_max > 0) { - /* - * First copy the keys. - */ - op = (char *)xfs_bmbt_key_addr(mp, ifp->if_broot, 1); - np = (char *)xfs_bmbt_key_addr(mp, new_broot, 1); - memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_key_t)); + 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)); + + /* + * First copy the keys. + */ + op = (char *)xfs_bmbt_key_addr(mp, ifp->if_broot, 1); + np = (char *)xfs_bmbt_key_addr(mp, new_broot, 1); + memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_key_t)); + + /* + * Then copy the pointers. + */ + op = (char *)xfs_bmap_broot_ptr_addr(mp, ifp->if_broot, 1, old_size); + np = (char *)xfs_bmap_broot_ptr_addr(mp, new_broot, 1, (int)new_size); + memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t)); - /* - * Then copy the pointers. - */ - op = (char *)xfs_bmap_broot_ptr_addr(mp, ifp->if_broot, 1, - ifp->if_broot_bytes); - np = (char *)xfs_bmap_broot_ptr_addr(mp, new_broot, 1, - (int)new_size); - memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t)); - } 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)); - return; + ASSERT(xfs_bmap_bmdr_space(ifp->if_broot) <= + xfs_inode_fork_size(ip, whichfork)); }