From 555936bfcb1af26c6919d6cedb83710bb03d4322 Mon Sep 17 00:00:00 2001 From: Tao Ma Date: Tue, 18 Aug 2009 11:22:21 +0800 Subject: [PATCH] ocfs2: Abstract extent split process. ocfs2_mark_extent_written actually does the following things: 1. check the parameters. 2. initialize the left_path and split_rec. 3. call __ocfs2_mark_extent_written. it will do: 1) check the flags of unwritten 2) do the real split work. The whole process is packed tightly somehow. So this patch will abstract 2 different functions so that future b-tree operation can work with it. 1. __ocfs2_split_extent will accept path and split_rec and do the real split work. 2. ocfs2_change_extent_flag will accept a new flag and initialize path and split_rec. So now ocfs2_mark_extent_written will do: 1. check the parameters. 2. call ocfs2_change_extent_flag. 1) initalize the left_path and split_rec. 2) check whether the new flags conflict with the old one. 3) call __ocfs2_split_extent to do the split. Signed-off-by: Tao Ma --- fs/ocfs2/alloc.c | 150 +++++++++++++++++++++++++++++++---------------- 1 file changed, 100 insertions(+), 50 deletions(-) diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index 75e65df34b69..14b9106849ca 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -5032,9 +5032,8 @@ static int ocfs2_replace_extent_rec(handle_t *handle, } /* - * Mark part or all of the extent record at split_index in the leaf - * pointed to by path as written. This removes the unwritten - * extent flag. + * Split part or all of the extent record at split_index in the leaf + * pointed to by path. Merge with the contiguous extent record if needed. * * Care is taken to handle contiguousness so as to not grow the tree. * @@ -5051,13 +5050,13 @@ static int ocfs2_replace_extent_rec(handle_t *handle, * have been brought into cache (and pinned via the journal), so the * extra overhead is not expressed in terms of disk reads. */ -static int __ocfs2_mark_extent_written(handle_t *handle, - struct ocfs2_extent_tree *et, - struct ocfs2_path *path, - int split_index, - struct ocfs2_extent_rec *split_rec, - struct ocfs2_alloc_context *meta_ac, - struct ocfs2_cached_dealloc_ctxt *dealloc) +static int __ocfs2_split_extent(handle_t *handle, + struct ocfs2_extent_tree *et, + struct ocfs2_path *path, + int split_index, + struct ocfs2_extent_rec *split_rec, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) { int ret = 0; struct ocfs2_extent_list *el = path_leaf_el(path); @@ -5066,12 +5065,6 @@ static int __ocfs2_mark_extent_written(handle_t *handle, struct ocfs2_merge_ctxt ctxt; struct ocfs2_extent_list *rightmost_el; - if (!(rec->e_flags & OCFS2_EXT_UNWRITTEN)) { - ret = -EIO; - mlog_errno(ret); - goto out; - } - if (le32_to_cpu(rec->e_cpos) > le32_to_cpu(split_rec->e_cpos) || ((le32_to_cpu(rec->e_cpos) + le16_to_cpu(rec->e_leaf_clusters)) < (le32_to_cpu(split_rec->e_cpos) + le16_to_cpu(split_rec->e_leaf_clusters)))) { @@ -5141,42 +5134,31 @@ static int __ocfs2_mark_extent_written(handle_t *handle, } /* - * Mark the already-existing extent at cpos as written for len clusters. + * Change the flags of the already-existing extent at cpos for len clusters. + * + * new_flags: the flags we want to set. + * clear_flags: the flags we want to clear. + * phys: the new physical offset we want this new extent starts from. * * If the existing extent is larger than the request, initiate a * split. An attempt will be made at merging with adjacent extents. * * The caller is responsible for passing down meta_ac if we'll need it. */ -int ocfs2_mark_extent_written(struct inode *inode, - struct ocfs2_extent_tree *et, - handle_t *handle, u32 cpos, u32 len, u32 phys, - struct ocfs2_alloc_context *meta_ac, - struct ocfs2_cached_dealloc_ctxt *dealloc) +static int ocfs2_change_extent_flag(handle_t *handle, + struct ocfs2_extent_tree *et, + u32 cpos, u32 len, u32 phys, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc, + int new_flags, int clear_flags) { int ret, index; - u64 start_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys); + struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci); + u64 start_blkno = ocfs2_clusters_to_blocks(sb, phys); struct ocfs2_extent_rec split_rec; struct ocfs2_path *left_path = NULL; struct ocfs2_extent_list *el; - - mlog(0, "Inode %lu cpos %u, len %u, phys %u (%llu)\n", - inode->i_ino, cpos, len, phys, (unsigned long long)start_blkno); - - if (!ocfs2_writes_unwritten_extents(OCFS2_SB(inode->i_sb))) { - ocfs2_error(inode->i_sb, "Inode %llu has unwritten extents " - "that are being written to, but the feature bit " - "is not set in the super block.", - (unsigned long long)OCFS2_I(inode)->ip_blkno); - ret = -EROFS; - goto out; - } - - /* - * XXX: This should be fixed up so that we just re-insert the - * next extent records. - */ - ocfs2_et_extent_map_truncate(et, 0); + struct ocfs2_extent_rec *rec; left_path = ocfs2_new_path_from_et(et); if (!left_path) { @@ -5194,30 +5176,98 @@ int ocfs2_mark_extent_written(struct inode *inode, index = ocfs2_search_extent_list(el, cpos); if (index == -1 || index >= le16_to_cpu(el->l_next_free_rec)) { - ocfs2_error(inode->i_sb, - "Inode %llu has an extent at cpos %u which can no " + ocfs2_error(sb, + "Owner %llu has an extent at cpos %u which can no " "longer be found.\n", - (unsigned long long)OCFS2_I(inode)->ip_blkno, cpos); + (unsigned long long) + ocfs2_metadata_cache_owner(et->et_ci), cpos); ret = -EROFS; goto out; } + ret = -EIO; + rec = &el->l_recs[index]; + if (new_flags && (rec->e_flags & new_flags)) { + mlog(ML_ERROR, "Owner %llu tried to set %d flags on an " + "extent that already had them", + (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci), + new_flags); + goto out; + } + + if (clear_flags && !(rec->e_flags & clear_flags)) { + mlog(ML_ERROR, "Owner %llu tried to clear %d flags on an " + "extent that didn't have them", + (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci), + clear_flags); + goto out; + } + memset(&split_rec, 0, sizeof(struct ocfs2_extent_rec)); split_rec.e_cpos = cpu_to_le32(cpos); split_rec.e_leaf_clusters = cpu_to_le16(len); split_rec.e_blkno = cpu_to_le64(start_blkno); - split_rec.e_flags = path_leaf_el(left_path)->l_recs[index].e_flags; - split_rec.e_flags &= ~OCFS2_EXT_UNWRITTEN; - - ret = __ocfs2_mark_extent_written(handle, et, left_path, - index, &split_rec, meta_ac, - dealloc); + split_rec.e_flags = rec->e_flags; + if (new_flags) + split_rec.e_flags |= new_flags; + if (clear_flags) + split_rec.e_flags &= ~clear_flags; + + ret = __ocfs2_split_extent(handle, et, left_path, + index, &split_rec, meta_ac, + dealloc); if (ret) mlog_errno(ret); out: ocfs2_free_path(left_path); return ret; + +} + +/* + * Mark the already-existing extent at cpos as written for len clusters. + * This removes the unwritten extent flag. + * + * If the existing extent is larger than the request, initiate a + * split. An attempt will be made at merging with adjacent extents. + * + * The caller is responsible for passing down meta_ac if we'll need it. + */ +int ocfs2_mark_extent_written(struct inode *inode, + struct ocfs2_extent_tree *et, + handle_t *handle, u32 cpos, u32 len, u32 phys, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + + mlog(0, "Inode %lu cpos %u, len %u, phys clusters %u\n", + inode->i_ino, cpos, len, phys); + + if (!ocfs2_writes_unwritten_extents(OCFS2_SB(inode->i_sb))) { + ocfs2_error(inode->i_sb, "Inode %llu has unwritten extents " + "that are being written to, but the feature bit " + "is not set in the super block.", + (unsigned long long)OCFS2_I(inode)->ip_blkno); + ret = -EROFS; + goto out; + } + + /* + * XXX: This should be fixed up so that we just re-insert the + * next extent records. + */ + ocfs2_et_extent_map_truncate(et, 0); + + ret = ocfs2_change_extent_flag(handle, et, cpos, + len, phys, meta_ac, dealloc, + 0, OCFS2_EXT_UNWRITTEN); + if (ret) + mlog_errno(ret); + +out: + return ret; } static int ocfs2_split_tree(handle_t *handle, struct ocfs2_extent_tree *et, -- GitLab