From 278d0ca14e889c3932a05d1a68675252a12b3466 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 30 Oct 2008 16:56:32 +1100 Subject: [XFS] implement generic xfs_btree_update From: Dave Chinner The most complicated part here is the lastrec tracking for the alloc btree. Most logic is in the update_lastrec method which has to do some hopefully good enough dirty magic to maintain it. [hch: split out from bigger patch and a rework of the lastrec logic] SGI-PV: 985583 SGI-Modid: xfs-linux-melb:xfs-kern:32194a Signed-off-by: Christoph Hellwig Signed-off-by: Lachlan McIlroy Signed-off-by: Bill O'Donnell Signed-off-by: David Chinner --- fs/xfs/xfs_btree.c | 121 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) (limited to 'fs/xfs/xfs_btree.c') diff --git a/fs/xfs/xfs_btree.c b/fs/xfs/xfs_btree.c index 1459a2b..205272f 100644 --- a/fs/xfs/xfs_btree.c +++ b/fs/xfs/xfs_btree.c @@ -988,6 +988,30 @@ xfs_btree_get_sibling( } } +/* + * Return true if ptr is the last record in the btree and + * we need to track updateѕ to this record. The decision + * will be further refined in the update_lastrec method. + */ +STATIC int +xfs_btree_is_lastrec( + struct xfs_btree_cur *cur, + struct xfs_btree_block *block, + int level) +{ + union xfs_btree_ptr ptr; + + if (level > 0) + return 0; + if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE)) + return 0; + + xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); + if (!xfs_btree_ptr_is_null(cur, &ptr)) + return 0; + return 1; +} + STATIC xfs_daddr_t xfs_btree_ptr_to_daddr( struct xfs_btree_cur *cur, @@ -1080,6 +1104,20 @@ xfs_btree_copy_keys( } /* + * Copy records from one btree block to another. + */ +STATIC void +xfs_btree_copy_recs( + struct xfs_btree_cur *cur, + union xfs_btree_rec *dst_rec, + union xfs_btree_rec *src_rec, + int numrecs) +{ + ASSERT(numrecs >= 0); + memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len); +} + +/* * Log key values from the btree block. */ STATIC void @@ -1105,6 +1143,26 @@ xfs_btree_log_keys( } /* + * Log record values from the btree block. + */ +STATIC void +xfs_btree_log_recs( + struct xfs_btree_cur *cur, + struct xfs_buf *bp, + int first, + int last) +{ + XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); + XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); + + xfs_trans_log_buf(cur->bc_tp, bp, + xfs_btree_rec_offset(cur, first), + xfs_btree_rec_offset(cur, last + 1) - 1); + + XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); +} + +/* * Increment cursor by one record at the level. * For nonzero levels the leaf-ward information is untouched. */ @@ -1576,3 +1634,66 @@ xfs_btree_updkey( XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); return 0; } + +/* + * Update the record referred to by cur to the value in the + * given record. This either works (return 0) or gets an + * EFSCORRUPTED error. + */ +int +xfs_btree_update( + struct xfs_btree_cur *cur, + union xfs_btree_rec *rec) +{ + struct xfs_btree_block *block; + struct xfs_buf *bp; + int error; + int ptr; + union xfs_btree_rec *rp; + + XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); + XFS_BTREE_TRACE_ARGR(cur, rec); + + /* Pick up the current block. */ + block = xfs_btree_get_block(cur, 0, &bp); + +#ifdef DEBUG + error = xfs_btree_check_block(cur, block, 0, bp); + if (error) + goto error0; +#endif + /* Get the address of the rec to be updated. */ + ptr = cur->bc_ptrs[0]; + rp = xfs_btree_rec_addr(cur, ptr, block); + + /* Fill in the new contents and log them. */ + xfs_btree_copy_recs(cur, rp, rec, 1); + xfs_btree_log_recs(cur, bp, ptr, ptr); + + /* + * If we are tracking the last record in the tree and + * we are at the far right edge of the tree, update it. + */ + if (xfs_btree_is_lastrec(cur, block, 0)) { + cur->bc_ops->update_lastrec(cur, block, rec, + ptr, LASTREC_UPDATE); + } + + /* Updating first rec in leaf. Pass new key value up to our parent. */ + if (ptr == 1) { + union xfs_btree_key key; + + cur->bc_ops->init_key_from_rec(&key, rec); + error = xfs_btree_updkey(cur, &key, 1); + if (error) + goto error0; + } + + XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); + return 0; + +error0: + XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); + return error; +} + -- cgit v1.1