From 7eccb903a817e890c947ba4bc90c6a9af9b4219a Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 11 Apr 2007 15:53:25 -0400 Subject: [PATCH] Btrfs: create a logical->phsyical block number mapping scheme Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 38 +++++------ fs/btrfs/ctree.h | 1 + fs/btrfs/disk-io.c | 140 ++++++++++++++++++++++++++++++----------- fs/btrfs/disk-io.h | 1 + fs/btrfs/extent-tree.c | 8 +-- fs/btrfs/super.c | 6 +- fs/btrfs/transaction.c | 8 +-- 7 files changed, 134 insertions(+), 68 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index f31ac843bf2e..e2fc6f0d0243 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -66,21 +66,21 @@ static int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root if (buf->b_size != root->blocksize || cow->b_size != root->blocksize) WARN_ON(1); memcpy(cow_node, btrfs_buffer_node(buf), root->blocksize); - btrfs_set_header_blocknr(&cow_node->header, cow->b_blocknr); + btrfs_set_header_blocknr(&cow_node->header, bh_blocknr(cow)); btrfs_set_header_generation(&cow_node->header, trans->transid); btrfs_inc_ref(trans, root, buf); if (buf == root->node) { root->node = cow; get_bh(cow); if (buf != root->commit_root) { - btrfs_free_extent(trans, root, buf->b_blocknr, 1, 1); + btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); } btrfs_block_release(root, buf); } else { btrfs_set_node_blockptr(btrfs_buffer_node(parent), parent_slot, - cow->b_blocknr); + bh_blocknr(cow)); btrfs_mark_buffer_dirty(parent); - btrfs_free_extent(trans, root, buf->b_blocknr, 1, 1); + btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); } btrfs_block_release(root, buf); mark_buffer_dirty(cow); @@ -312,7 +312,7 @@ static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root */ if (!parent_buf) { struct buffer_head *child; - u64 blocknr = mid_buf->b_blocknr; + u64 blocknr = bh_blocknr(mid_buf); if (btrfs_header_nritems(&mid->header) != 1) return 0; @@ -361,7 +361,7 @@ static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root if (wret < 0) ret = wret; if (btrfs_header_nritems(&right->header) == 0) { - u64 blocknr = right_buf->b_blocknr; + u64 blocknr = bh_blocknr(right_buf); clean_tree_block(trans, root, right_buf); wait_on_buffer(right_buf); btrfs_block_release(root, right_buf); @@ -400,7 +400,7 @@ static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root } if (btrfs_header_nritems(&mid->header) == 0) { /* we've managed to empty the middle node, drop it */ - u64 blocknr = mid_buf->b_blocknr; + u64 blocknr = bh_blocknr(mid_buf); clean_tree_block(trans, root, mid_buf); wait_on_buffer(mid_buf); btrfs_block_release(root, mid_buf); @@ -686,7 +686,7 @@ static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root memset(c, 0, root->blocksize); btrfs_set_header_nritems(&c->header, 1); btrfs_set_header_level(&c->header, level); - btrfs_set_header_blocknr(&c->header, t->b_blocknr); + btrfs_set_header_blocknr(&c->header, bh_blocknr(t)); btrfs_set_header_generation(&c->header, trans->transid); lower = btrfs_buffer_node(path->nodes[level-1]); memcpy(c->header.fsid, root->fs_info->disk_super->fsid, @@ -697,7 +697,7 @@ static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root lower_key = &lower->ptrs[0].key; btrfs_memcpy(root, c, &c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key)); - btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->b_blocknr); + btrfs_set_node_blockptr(c, 0, bh_blocknr(path->nodes[level - 1])); btrfs_mark_buffer_dirty(t); @@ -780,7 +780,7 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root split = btrfs_buffer_node(split_buffer); btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); btrfs_set_header_level(&split->header, btrfs_header_level(&c->header)); - btrfs_set_header_blocknr(&split->header, split_buffer->b_blocknr); + btrfs_set_header_blocknr(&split->header, bh_blocknr(split_buffer)); btrfs_set_header_generation(&split->header, trans->transid); memcpy(split->header.fsid, root->fs_info->disk_super->fsid, sizeof(split->header.fsid)); @@ -794,7 +794,7 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_mark_buffer_dirty(t); btrfs_mark_buffer_dirty(split_buffer); wret = insert_ptr(trans, root, path, &split->ptrs[0].key, - split_buffer->b_blocknr, path->slots[level + 1] + 1, + bh_blocknr(split_buffer), path->slots[level + 1] + 1, level + 1); if (wret) ret = wret; @@ -1138,7 +1138,7 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root BUG_ON(!right_buffer); right = btrfs_buffer_leaf(right_buffer); memset(&right->header, 0, sizeof(right->header)); - btrfs_set_header_blocknr(&right->header, right_buffer->b_blocknr); + btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); btrfs_set_header_generation(&right->header, trans->transid); btrfs_set_header_level(&right->header, 0); memcpy(right->header.fsid, root->fs_info->disk_super->fsid, @@ -1152,7 +1152,7 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_set_header_nritems(&right->header, 0); wret = insert_ptr(trans, root, path, &disk_key, - right_buffer->b_blocknr, + bh_blocknr(right_buffer), path->slots[1] + 1, 1); if (wret) ret = wret; @@ -1173,7 +1173,7 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_set_header_nritems(&right->header, 0); wret = insert_ptr(trans, root, path, &disk_key, - right_buffer->b_blocknr, + bh_blocknr(right_buffer), path->slots[1] - 1, 1); if (wret) ret = wret; @@ -1207,7 +1207,7 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_set_header_nritems(&l->header, mid); ret = 0; wret = insert_ptr(trans, root, path, &right->items[0].key, - right_buffer->b_blocknr, path->slots[1] + 1, 1); + bh_blocknr(right_buffer), path->slots[1] + 1, 1); if (wret) ret = wret; btrfs_mark_buffer_dirty(right_buffer); @@ -1228,7 +1228,7 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root BUG_ON(!right_buffer); right = btrfs_buffer_leaf(right_buffer); memset(&right->header, 0, sizeof(right->header)); - btrfs_set_header_blocknr(&right->header, right_buffer->b_blocknr); + btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); btrfs_set_header_generation(&right->header, trans->transid); btrfs_set_header_level(&right->header, 0); memcpy(right->header.fsid, root->fs_info->disk_super->fsid, @@ -1237,7 +1237,7 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_set_header_nritems(&right->header, 0); wret = insert_ptr(trans, root, path, &disk_key, - right_buffer->b_blocknr, + bh_blocknr(right_buffer), path->slots[1], 1); if (wret) ret = wret; @@ -1456,7 +1456,7 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, if (wret) ret = wret; wret = btrfs_free_extent(trans, root, - leaf_buf->b_blocknr, 1, 1); + bh_blocknr(leaf_buf), 1, 1); if (wret) ret = wret; } @@ -1487,7 +1487,7 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, ret = wret; } if (btrfs_header_nritems(&leaf->header) == 0) { - u64 blocknr = leaf_buf->b_blocknr; + u64 blocknr = bh_blocknr(leaf_buf); clean_tree_block(trans, root, leaf_buf); wait_on_buffer(leaf_buf); wret = del_ptr(trans, root, path, 1, slot); diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 01310de2bf4a..454eb88611bb 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -242,6 +242,7 @@ struct btrfs_fs_info { struct radix_tree_root fs_roots_radix; struct radix_tree_root pending_del_radix; struct radix_tree_root pinned_radix; + struct radix_tree_root dev_radix; u64 generation; struct btrfs_transaction *running_transaction; struct btrfs_super_block *disk_super; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index e09233262af6..c872a7e67abd 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -10,10 +10,30 @@ #include "transaction.h" #include "btrfs_inode.h" +struct dev_lookup { + u64 block_start; + u64 num_blocks; + struct block_device *bdev; +}; + +u64 bh_blocknr(struct buffer_head *bh) +{ + int blkbits = bh->b_page->mapping->host->i_blkbits; + u64 blocknr = bh->b_page->index << (PAGE_CACHE_SHIFT - blkbits); + unsigned long offset; + + if (PageHighMem(bh->b_page)) + offset = (unsigned long)bh->b_data; + else + offset = bh->b_data - (char *)page_address(bh->b_page); + blocknr += offset >> (PAGE_CACHE_SHIFT - blkbits); + return blocknr; +} + static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf) { struct btrfs_node *node = btrfs_buffer_node(buf); - if (buf->b_blocknr != btrfs_header_blocknr(&node->header)) { + if (bh_blocknr(buf) != btrfs_header_blocknr(&node->header)) { BUG(); } return 0; @@ -40,7 +60,7 @@ struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr) head = page_buffers(page); bh = head; do { - if (buffer_mapped(bh) && bh->b_blocknr == blocknr) { + if (buffer_mapped(bh) && bh_blocknr(bh) == blocknr) { ret = bh; get_bh(bh); goto out_unlock; @@ -56,6 +76,33 @@ out_unlock: return ret; } +static int map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh, + u64 logical) +{ + struct dev_lookup *lookup[2]; + char b[BDEVNAME_SIZE]; + + int ret; + + root = root->fs_info->dev_root; + ret = radix_tree_gang_lookup(&root->fs_info->dev_radix, + (void **)lookup, + (unsigned long)logical, + ARRAY_SIZE(lookup)); + if (ret == 0 || lookup[0]->block_start > logical || + lookup[0]->block_start + lookup[0]->num_blocks <= logical) { + ret = -ENOENT; + goto out; + } + bh->b_bdev = lookup[0]->bdev; + bh->b_blocknr = logical - lookup[0]->block_start; +printk("logical mapping %Lu to %lu bdev %s\n", logical, bh->b_blocknr, bdevname(bh->b_bdev, b)); + set_buffer_mapped(bh); + ret = 0; +out: + return ret; +} + struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root, u64 blocknr) { @@ -66,6 +113,7 @@ struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root, struct buffer_head *bh; struct buffer_head *head; struct buffer_head *ret = NULL; + int err; u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits); page = grab_cache_page(mapping, index); @@ -78,11 +126,10 @@ struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root, bh = head; do { if (!buffer_mapped(bh)) { - bh->b_bdev = root->fs_info->sb->s_bdev; - bh->b_blocknr = first_block; - set_buffer_mapped(bh); + err = map_bh_to_logical(root, bh, first_block); + BUG_ON(err); } - if (bh->b_blocknr == blocknr) { + if (bh_blocknr(bh) == blocknr) { ret = bh; get_bh(bh); goto out_unlock; @@ -98,38 +145,13 @@ out_unlock: return ret; } -static sector_t max_block(struct block_device *bdev) -{ - sector_t retval = ~((sector_t)0); - loff_t sz = i_size_read(bdev->bd_inode); - - if (sz) { - unsigned int size = block_size(bdev); - unsigned int sizebits = blksize_bits(size); - retval = (sz >> sizebits); - } - return retval; -} - static int btree_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh, int create) { - if (iblock >= max_block(inode->i_sb->s_bdev)) { - if (create) - return -EIO; - - /* - * for reads, we're just trying to fill a partial page. - * return a hole, they will have to call get_block again - * before they can fill it, and they will get -EIO at that - * time - */ - return 0; - } - bh->b_bdev = inode->i_sb->s_bdev; - bh->b_blocknr = iblock; - set_buffer_mapped(bh); - return 0; + int err; + struct btrfs_root *root = BTRFS_I(bh->b_page->mapping->host)->root; + err = map_bh_to_logical(root, bh, iblock); + return err; } int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len, @@ -164,8 +186,8 @@ static int csum_tree_block(struct btrfs_root *root, struct buffer_head *bh, return ret; if (verify) { if (memcmp(bh->b_data, result, BTRFS_CSUM_SIZE)) { - printk("checksum verify failed on %lu\n", - bh->b_blocknr); + printk("checksum verify failed on %Lu\n", + bh_blocknr(bh)); return 1; } } else { @@ -386,10 +408,12 @@ struct btrfs_root *open_ctree(struct super_block *sb) GFP_NOFS); int ret; struct btrfs_super_block *disk_super; + struct dev_lookup *dev_lookup; init_bit_radix(&fs_info->pinned_radix); init_bit_radix(&fs_info->pending_del_radix); INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS); + INIT_RADIX_TREE(&fs_info->dev_radix, GFP_NOFS); sb_set_blocksize(sb, 4096); fs_info->running_transaction = NULL; fs_info->tree_root = tree_root; @@ -422,6 +446,13 @@ struct btrfs_root *open_ctree(struct super_block *sb) __setup_root(sb->s_blocksize, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID); + + dev_lookup = kmalloc(sizeof(*dev_lookup), GFP_NOFS); + dev_lookup->block_start = 0; + dev_lookup->num_blocks = (u32)-2; + dev_lookup->bdev = sb->s_bdev; + ret = radix_tree_insert(&fs_info->dev_radix, (u32)-2, dev_lookup); + BUG_ON(ret); fs_info->sb_buffer = read_tree_block(tree_root, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize); @@ -432,6 +463,14 @@ struct btrfs_root *open_ctree(struct super_block *sb) if (!btrfs_super_root(disk_super)) return NULL; + radix_tree_delete(&fs_info->dev_radix, (u32)-2); + dev_lookup->block_start = btrfs_super_device_block_start(disk_super); + dev_lookup->num_blocks = btrfs_super_device_num_blocks(disk_super); + ret = radix_tree_insert(&fs_info->dev_radix, + dev_lookup->block_start + + dev_lookup->num_blocks, dev_lookup); + BUG_ON(ret); + fs_info->disk_super = disk_super; dev_root->node = read_tree_block(tree_root, btrfs_super_device_root(disk_super)); @@ -459,7 +498,7 @@ int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root struct buffer_head *bh = root->fs_info->sb_buffer; btrfs_set_super_root(root->fs_info->disk_super, - root->fs_info->tree_root->node->b_blocknr); + bh_blocknr(root->fs_info->tree_root->node)); lock_buffer(bh); WARN_ON(atomic_read(&bh->b_count) < 1); clear_buffer_dirty(bh); @@ -506,6 +545,29 @@ int del_fs_roots(struct btrfs_fs_info *fs_info) } return 0; } +static int free_dev_radix(struct btrfs_fs_info *fs_info) +{ + struct dev_lookup *lookup[8]; + struct block_device *super_bdev = fs_info->sb->s_bdev; + int ret; + int i; + while(1) { + ret = radix_tree_gang_lookup(&fs_info->dev_radix, + (void **)lookup, 0, + ARRAY_SIZE(lookup)); + if (!ret) + break; + for (i = 0; i < ret; i++) { + if (lookup[i]->bdev != super_bdev) + close_bdev_excl(lookup[i]->bdev); + radix_tree_delete(&fs_info->dev_radix, + lookup[i]->block_start + + lookup[i]->num_blocks); + kfree(lookup[i]); + } + } + return 0; +} int close_ctree(struct btrfs_root *root) { @@ -537,6 +599,8 @@ int close_ctree(struct btrfs_root *root) crypto_free_hash(fs_info->hash_tfm); truncate_inode_pages(fs_info->btree_inode->i_mapping, 0); iput(fs_info->btree_inode); + + free_dev_radix(fs_info); del_fs_roots(fs_info); kfree(fs_info->extent_root); kfree(fs_info->tree_root); diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h index 0ef6e6f714af..46cc5dc9d572 100644 --- a/fs/btrfs/disk-io.h +++ b/fs/btrfs/disk-io.h @@ -41,4 +41,5 @@ int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len, char *result); struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_key *location); +u64 bh_blocknr(struct buffer_head *bh); #endif diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index be9630df506c..d560831c10a7 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -80,7 +80,7 @@ static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root int btrfs_inc_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root) { - return inc_block_ref(trans, root, root->node->b_blocknr, 1); + return inc_block_ref(trans, root, bh_blocknr(root->node), 1); } int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, @@ -563,7 +563,7 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); - ret = lookup_block_ref(trans, root, path->nodes[*level]->b_blocknr, + ret = lookup_block_ref(trans, root, bh_blocknr(path->nodes[*level]), 1, &refs); BUG_ON(ret); if (refs > 1) @@ -607,7 +607,7 @@ out: WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); ret = btrfs_free_extent(trans, root, - path->nodes[*level]->b_blocknr, 1, 1); + bh_blocknr(path->nodes[*level]), 1, 1); btrfs_block_release(root, path->nodes[*level]); path->nodes[*level] = NULL; *level += 1; @@ -635,7 +635,7 @@ static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root return 0; } else { ret = btrfs_free_extent(trans, root, - path->nodes[*level]->b_blocknr, + bh_blocknr(path->nodes[*level]), 1, 1); BUG_ON(ret); btrfs_block_release(root, path->nodes[*level]); diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 2972aaa9eb7e..4ff0cc1efb13 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1700,7 +1700,7 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen) leaf = btrfs_buffer_leaf(subvol); btrfs_set_header_nritems(&leaf->header, 0); btrfs_set_header_level(&leaf->header, 0); - btrfs_set_header_blocknr(&leaf->header, subvol->b_blocknr); + btrfs_set_header_blocknr(&leaf->header, bh_blocknr(subvol)); btrfs_set_header_generation(&leaf->header, trans->transid); memcpy(leaf->header.fsid, root->fs_info->disk_super->fsid, sizeof(leaf->header.fsid)); @@ -1713,7 +1713,7 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen) btrfs_set_inode_nblocks(inode_item, 1); btrfs_set_inode_mode(inode_item, S_IFDIR | 0755); - btrfs_set_root_blocknr(&root_item, subvol->b_blocknr); + btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol)); btrfs_set_root_refs(&root_item, 1); mark_buffer_dirty(subvol); @@ -1803,7 +1803,7 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen) key.offset = 1; key.flags = 0; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); - btrfs_set_root_blocknr(&new_root_item, root->node->b_blocknr); + btrfs_set_root_blocknr(&new_root_item, bh_blocknr(root->node)); ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, &new_root_item); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index e15a072407bf..3a15943ea8ed 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -119,10 +119,10 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans, while(1) { old_extent_block = btrfs_root_blocknr(&extent_root->root_item); - if (old_extent_block == extent_root->node->b_blocknr) + if (old_extent_block == bh_blocknr(extent_root->node)) break; btrfs_set_root_blocknr(&extent_root->root_item, - extent_root->node->b_blocknr); + bh_blocknr(extent_root->node)); ret = btrfs_update_root(trans, tree_root, &extent_root->root_key, &extent_root->root_item); @@ -176,7 +176,7 @@ int add_dirty_roots(struct btrfs_trans_handle *trans, (unsigned long)root->root_key.objectid, BTRFS_ROOT_TRANS_TAG); if (root->commit_root == root->node) { - WARN_ON(root->node->b_blocknr != + WARN_ON(bh_blocknr(root->node) != btrfs_root_blocknr(&root->root_item)); brelse(root->commit_root); root->commit_root = NULL; @@ -191,7 +191,7 @@ int add_dirty_roots(struct btrfs_trans_handle *trans, dirty->root = root; root->root_key.offset = root->fs_info->generation; btrfs_set_root_blocknr(&root->root_item, - root->node->b_blocknr); + bh_blocknr(root->node)); err = btrfs_insert_root(trans, root->fs_info->tree_root, &root->root_key, &root->root_item); -- 2.30.2