diff options
Diffstat (limited to 'fs/btrfs/extent-tree.c')
-rw-r--r-- | fs/btrfs/extent-tree.c | 373 |
1 files changed, 311 insertions, 62 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 0f1ebdd4e925..32991f73e9db 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -17,6 +17,7 @@ */ #include <linux/sched.h> +#include <linux/crc32c.h> #include "hash.h" #include "ctree.h" #include "disk-io.h" @@ -89,7 +90,8 @@ static int cache_block_group(struct btrfs_root *root, btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid < block_group->key.objectid) { - if (key.objectid + key.offset > first_free) + if (btrfs_key_type(&key) != BTRFS_EXTENT_REF_KEY && + key.objectid + key.offset > first_free) first_free = key.objectid + key.offset; goto next; } @@ -353,7 +355,7 @@ found: return found_group; } -static u64 hash_extent_ref(u64 root_objectid, u64 root_generation, +static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation, u64 owner, u64 owner_offset) { u32 high_crc = ~(u32)0; @@ -362,53 +364,149 @@ static u64 hash_extent_ref(u64 root_objectid, u64 root_generation, lenum = cpu_to_le64(root_objectid); high_crc = crc32c(high_crc, &lenum, sizeof(lenum)); - lenum = cpu_to_le64(root_generation); - high_crc = crc32c(high_crc, &lenum, sizeof(lenum)); + lenum = cpu_to_le64(ref_generation); + low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); +#if 0 lenum = cpu_to_le64(owner); low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); - lenum = cpu_to_le64(owner_offset); low_crc = crc32c(low_crc, &lenum, sizeof(lenum)); - +#endif return ((u64)high_crc << 32) | (u64)low_crc; } -int insert_extent_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, - u64 bytenr, - u64 root_objectid, u64 root_generation, - u64 owner, u64 owner_offset) +static int match_extent_ref(struct extent_buffer *leaf, + struct btrfs_extent_ref *disk_ref, + struct btrfs_extent_ref *cpu_ref) +{ + int ret; + int len; + + if (cpu_ref->objectid) + len = sizeof(*cpu_ref); + else + len = 2 * sizeof(u64); + ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref, + len); + return ret == 0; +} + +static int lookup_extent_backref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, u64 bytenr, + u64 root_objectid, u64 ref_generation, + u64 owner, u64 owner_offset, int del) { u64 hash; struct btrfs_key key; + struct btrfs_key found_key; struct btrfs_extent_ref ref; - struct extent_buffer *l; - struct btrfs_extent_item *item; + struct extent_buffer *leaf; + struct btrfs_extent_ref *disk_ref; + int ret; + int ret2; + + btrfs_set_stack_ref_root(&ref, root_objectid); + btrfs_set_stack_ref_generation(&ref, ref_generation); + btrfs_set_stack_ref_objectid(&ref, owner); + btrfs_set_stack_ref_offset(&ref, owner_offset); + + hash = hash_extent_ref(root_objectid, ref_generation, owner, + owner_offset); + key.offset = hash; + key.objectid = bytenr; + key.type = BTRFS_EXTENT_REF_KEY; + + while (1) { + ret = btrfs_search_slot(trans, root, &key, path, + del ? -1 : 0, del); + if (ret < 0) + goto out; + leaf = path->nodes[0]; + if (ret != 0) { + u32 nritems = btrfs_header_nritems(leaf); + if (path->slots[0] >= nritems) { + ret2 = btrfs_next_leaf(root, path); + if (ret2) + goto out; + leaf = path->nodes[0]; + } + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != bytenr || + found_key.type != BTRFS_EXTENT_REF_KEY) + goto out; + key.offset = found_key.offset; + if (del) { + btrfs_release_path(root, path); + continue; + } + } + disk_ref = btrfs_item_ptr(path->nodes[0], + path->slots[0], + struct btrfs_extent_ref); + if (match_extent_ref(path->nodes[0], disk_ref, &ref)) { + ret = 0; + goto out; + } + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + key.offset = found_key.offset + 1; + btrfs_release_path(root, path); + } +out: + return ret; +} + +int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, u64 bytenr, + u64 root_objectid, u64 ref_generation, + u64 owner, u64 owner_offset) +{ + u64 hash; + struct btrfs_key key; + struct btrfs_extent_ref ref; + struct btrfs_extent_ref *disk_ref; int ret; btrfs_set_stack_ref_root(&ref, root_objectid); - btrfs_set_stack_ref_generation(&ref, root_generation); + btrfs_set_stack_ref_generation(&ref, ref_generation); btrfs_set_stack_ref_objectid(&ref, owner); btrfs_set_stack_ref_offset(&ref, owner_offset); - ret = btrfs_name_hash(&ref, sizeof(ref), &hash); + hash = hash_extent_ref(root_objectid, ref_generation, owner, + owner_offset); key.offset = hash; key.objectid = bytenr; key.type = BTRFS_EXTENT_REF_KEY; ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref)); while (ret == -EEXIST) { - + disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_extent_ref); + if (match_extent_ref(path->nodes[0], disk_ref, &ref)) + goto out; + key.offset++; + btrfs_release_path(root, path); + ret = btrfs_insert_empty_item(trans, root, path, &key, + sizeof(ref)); } - + if (ret) + goto out; + disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_extent_ref); + write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref, + sizeof(ref)); + btrfs_mark_buffer_dirty(path->nodes[0]); +out: + btrfs_release_path(root, path); + return ret; } int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, - u64 root_objectid, u64 root_generation, + u64 root_objectid, u64 ref_generation, u64 owner, u64 owner_offset) { struct btrfs_path *path; @@ -441,6 +539,11 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(path->nodes[0]); btrfs_release_path(root->fs_info->extent_root, path); + + ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root, + path, bytenr, root_objectid, + ref_generation, owner, owner_offset); + BUG_ON(ret); finish_current_insert(trans, root->fs_info->extent_root); del_pending_extents(trans, root->fs_info->extent_root); @@ -489,10 +592,29 @@ out: } int btrfs_inc_root_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root) + struct btrfs_root *root, u64 owner_objectid) { + u64 generation; + u64 key_objectid; + u64 level; + u32 nritems; + struct btrfs_disk_key disk_key; + + level = btrfs_header_level(root->node); + generation = trans->transid; + nritems = btrfs_header_nritems(root->node); + if (nritems > 0) { + if (level == 0) + btrfs_item_key(root->node, &disk_key, 0); + else + btrfs_node_key(root->node, &disk_key, 0); + key_objectid = btrfs_disk_key_objectid(&disk_key); + } else { + key_objectid = 0; + } return btrfs_inc_extent_ref(trans, root, root->node->start, - root->node->len); + root->node->len, owner_objectid, + generation, 0, 0); } int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, @@ -506,7 +628,6 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, int level; int ret; int faili; - int err; if (!root->ref_cows) return 0; @@ -528,7 +649,9 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, if (disk_bytenr == 0) continue; ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, - btrfs_file_extent_disk_num_bytes(buf, fi)); + btrfs_file_extent_disk_num_bytes(buf, fi), + root->root_key.objectid, trans->transid, + key.objectid, key.offset); if (ret) { faili = i; goto fail; @@ -536,7 +659,9 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, } else { bytenr = btrfs_node_blockptr(buf, i); ret = btrfs_inc_extent_ref(trans, root, bytenr, - btrfs_level_size(root, level - 1)); + btrfs_level_size(root, level - 1), + root->root_key.objectid, + trans->transid, 0, 0); if (ret) { faili = i; goto fail; @@ -546,6 +671,7 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, return 0; fail: WARN_ON(1); +#if 0 for (i =0; i < faili; i++) { if (level == 0) { u64 disk_bytenr; @@ -571,6 +697,7 @@ fail: BUG_ON(err); } } +#endif return ret; } @@ -809,18 +936,18 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, static int finish_current_insert(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root) { + u64 start; + u64 end; + struct btrfs_fs_info *info = extent_root->fs_info; + struct btrfs_path *path; struct btrfs_key ins; struct btrfs_extent_item extent_item; int ret; int err = 0; - u64 start; - u64 end; - struct btrfs_fs_info *info = extent_root->fs_info; btrfs_set_stack_extent_refs(&extent_item, 1); btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY); - btrfs_set_stack_extent_owner(&extent_item, - extent_root->root_key.objectid); + path = btrfs_alloc_path(); while(1) { ret = find_first_extent_bit(&info->extent_ins, 0, &start, @@ -834,7 +961,12 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct &extent_item, sizeof(extent_item)); clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED, GFP_NOFS); + err = btrfs_insert_extent_backref(trans, extent_root, path, + start, extent_root->root_key.objectid, + 0, 0, 0); + BUG_ON(err); } + btrfs_free_path(path); return 0; } @@ -871,7 +1003,9 @@ static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes, * remove an extent from the root, returns 0 on success */ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root - *root, u64 bytenr, u64 num_bytes, int pin, + *root, u64 bytenr, u64 num_bytes, + u64 root_objectid, u64 ref_generation, + u64 owner_objectid, u64 owner_offset, int pin, int mark_free) { struct btrfs_path *path; @@ -891,6 +1025,24 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root if (!path) return -ENOMEM; + if (ref_generation && owner_objectid == 0 && root_objectid == 3) { +//printk("drop backref root %Lu gen %Lu byte %Lu\n", root_objectid, ref_generation, bytenr ); + } + ret = lookup_extent_backref(trans, extent_root, path, + bytenr, root_objectid, + ref_generation, + owner_objectid, owner_offset, 1); + if (ret == 0) { + ret = btrfs_del_item(trans, extent_root, path); + } else { + btrfs_print_leaf(extent_root, path->nodes[0]); + WARN_ON(1); + printk("Unable to find ref byte nr %Lu root %Lu " + " gen %Lu owner %Lu offset %Lu\n", bytenr, + root_objectid, ref_generation, owner_objectid, + owner_offset); + } + btrfs_release_path(extent_root, path); ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); if (ret < 0) return ret; @@ -965,7 +1117,9 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct clear_extent_bits(pending_del, start, end, EXTENT_LOCKED, GFP_NOFS); ret = __free_extent(trans, extent_root, - start, end + 1 - start, 0, 0); + start, end + 1 - start, + extent_root->root_key.objectid, + 0, 0, 0, 0, 0); if (ret) err = ret; } @@ -976,18 +1130,25 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct * remove an extent from the root, returns 0 on success */ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root - *root, u64 bytenr, u64 num_bytes, int pin) + *root, u64 bytenr, u64 num_bytes, + u64 root_objectid, u64 ref_generation, + u64 owner_objectid, u64 owner_offset, int pin) { struct btrfs_root *extent_root = root->fs_info->extent_root; int pending_ret; int ret; WARN_ON(num_bytes < root->sectorsize); + if (!root->ref_cows) + ref_generation = 0; + if (root == extent_root) { pin_down_bytes(root, bytenr, num_bytes, 1); return 0; } - ret = __free_extent(trans, root, bytenr, num_bytes, pin, pin == 0); + ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid, + ref_generation, owner_objectid, owner_offset, + pin, pin == 0); pending_ret = del_pending_extents(trans, root->fs_info->extent_root); return ret ? ret : pending_ret; } @@ -1080,23 +1241,26 @@ check_failed: btrfs_item_key_to_cpu(l, &key, path->slots[0]); /* - * a rare case, go back one key if we hit a block group item - * instead of an extent item + * walk backwards to find the first extent item key */ - if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY && - key.objectid + key.offset >= search_start) { - ins->objectid = key.objectid; - ins->offset = key.offset - 1; - btrfs_release_path(root, path); - ret = btrfs_search_slot(trans, root, ins, path, 0, 0); - if (ret < 0) - goto error; - - if (path->slots[0] > 0) { + while(btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY) { + if (path->slots[0] == 0) { + ret = btrfs_prev_leaf(root, path); + if (ret != 0) { + ret = btrfs_search_slot(trans, root, ins, + path, 0, 0); + if (ret < 0) + goto error; + if (path->slots[0] > 0) + path->slots[0]--; + break; + } + } else { path->slots[0]--; } + l = path->nodes[0]; + btrfs_item_key_to_cpu(l, &key, path->slots[0]); } - while (1) { l = path->nodes[0]; slot = path->slots[0]; @@ -1146,7 +1310,8 @@ check_failed: } } if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY) { - if (!start_found) { + if (!start_found && btrfs_key_type(&key) == + BTRFS_BLOCK_GROUP_ITEM_KEY) { last_byte = key.objectid; start_found = 1; } @@ -1244,8 +1409,10 @@ error: * returns 0 if everything worked, non-zero otherwise. */ int btrfs_alloc_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 owner, - u64 num_bytes, u64 empty_size, u64 hint_byte, + struct btrfs_root *root, + u64 num_bytes, u64 root_objectid, u64 ref_generation, + u64 owner, u64 owner_offset, + u64 empty_size, u64 hint_byte, u64 search_end, struct btrfs_key *ins, int data) { int ret; @@ -1255,9 +1422,9 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans, struct btrfs_fs_info *info = root->fs_info; struct btrfs_root *extent_root = info->extent_root; struct btrfs_extent_item extent_item; + struct btrfs_path *path; btrfs_set_stack_extent_refs(&extent_item, 1); - btrfs_set_stack_extent_owner(&extent_item, owner); WARN_ON(num_bytes < root->sectorsize); ret = find_free_extent(trans, root, num_bytes, empty_size, @@ -1296,8 +1463,16 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans, trans->alloc_exclude_start = 0; trans->alloc_exclude_nr = 0; + BUG_ON(ret); + + path = btrfs_alloc_path(); + BUG_ON(!path); + ret = btrfs_insert_extent_backref(trans, extent_root, path, + ins->objectid, root_objectid, + ref_generation, owner, owner_offset); BUG_ON(ret); + btrfs_free_path(path); finish_current_insert(trans, extent_root); pending_ret = del_pending_extents(trans, extent_root); @@ -1321,15 +1496,43 @@ update_block: */ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, - u32 blocksize, u64 hint, + u32 blocksize, + u64 root_objectid, u64 hint, + u64 empty_size) +{ + u64 ref_generation; + + if (root->ref_cows) + ref_generation = trans->transid; + else + ref_generation = 0; + + + return __btrfs_alloc_free_block(trans, root, blocksize, root_objectid, + ref_generation, 0, 0, hint, empty_size); +} + +/* + * helper function to allocate a block for a given tree + * returns the tree buffer or NULL. + */ +struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u32 blocksize, + u64 root_objectid, + u64 ref_generation, + u64 first_objectid, + int level, + u64 hint, u64 empty_size) { struct btrfs_key ins; int ret; struct extent_buffer *buf; - ret = btrfs_alloc_extent(trans, root, root->root_key.objectid, - blocksize, empty_size, hint, + ret = btrfs_alloc_extent(trans, root, blocksize, + root_objectid, ref_generation, + first_objectid, level, empty_size, hint, (u64)-1, &ins, 0); if (ret) { BUG_ON(ret > 0); @@ -1337,7 +1540,9 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, } buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize); if (!buf) { - btrfs_free_extent(trans, root, ins.objectid, blocksize, 0); + btrfs_free_extent(trans, root, ins.objectid, blocksize, + root->root_key.objectid, ref_generation, + 0, 0, 0); return ERR_PTR(-ENOMEM); } btrfs_set_buffer_uptodate(buf); @@ -1355,6 +1560,8 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, static int drop_leaf_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *leaf) { + u64 leaf_owner; + u64 leaf_generation; struct btrfs_key key; struct btrfs_file_extent_item *fi; int i; @@ -1363,6 +1570,9 @@ static int drop_leaf_ref(struct btrfs_trans_handle *trans, BUG_ON(!btrfs_is_leaf(leaf)); nritems = btrfs_header_nritems(leaf); + leaf_owner = btrfs_header_owner(leaf); + leaf_generation = btrfs_header_generation(leaf); + for (i = 0; i < nritems; i++) { u64 disk_bytenr; @@ -1381,7 +1591,9 @@ static int drop_leaf_ref(struct btrfs_trans_handle *trans, if (disk_bytenr == 0) continue; ret = btrfs_free_extent(trans, root, disk_bytenr, - btrfs_file_extent_disk_num_bytes(leaf, fi), 0); + btrfs_file_extent_disk_num_bytes(leaf, fi), + leaf_owner, leaf_generation, + key.objectid, key.offset, 0); BUG_ON(ret); } return 0; @@ -1423,9 +1635,12 @@ static void reada_walk_down(struct btrfs_root *root, static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, int *level) { + u64 root_owner; + u64 root_gen; + u64 bytenr; struct extent_buffer *next; struct extent_buffer *cur; - u64 bytenr; + struct extent_buffer *parent; u32 blocksize; int ret; u32 refs; @@ -1466,9 +1681,13 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs); BUG_ON(ret); if (refs != 1) { + parent = path->nodes[*level]; + root_owner = btrfs_header_owner(parent); + root_gen = btrfs_header_generation(parent); path->slots[*level]++; ret = btrfs_free_extent(trans, root, bytenr, - blocksize, 1); + blocksize, root_owner, + root_gen, 0, 0, 1); BUG_ON(ret); continue; } @@ -1484,10 +1703,16 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root blocksize, &refs); BUG_ON(ret); if (refs != 1) { + parent = path->nodes[*level]; + root_owner = btrfs_header_owner(parent); + root_gen = btrfs_header_generation(parent); + path->slots[*level]++; free_extent_buffer(next); - ret = btrfs_free_extent(trans, root, - bytenr, blocksize, 1); + ret = btrfs_free_extent(trans, root, bytenr, + blocksize, + root_owner, + root_gen, 0, 0, 1); BUG_ON(ret); continue; } @@ -1502,8 +1727,19 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root out: WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); + + if (path->nodes[*level] == root->node) { + root_owner = root->root_key.objectid; + parent = path->nodes[*level]; + } else { + parent = path->nodes[*level + 1]; + root_owner = btrfs_header_owner(parent); + } + + root_gen = btrfs_header_generation(parent); ret = btrfs_free_extent(trans, root, path->nodes[*level]->start, - path->nodes[*level]->len, 1); + path->nodes[*level]->len, + root_owner, root_gen, 0, 0, 1); free_extent_buffer(path->nodes[*level]); path->nodes[*level] = NULL; *level += 1; @@ -1519,10 +1755,12 @@ out: static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, int *level) { + u64 root_owner; + u64 root_gen; + struct btrfs_root_item *root_item = &root->root_item; int i; int slot; int ret; - struct btrfs_root_item *root_item = &root->root_item; for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { slot = path->slots[i]; @@ -1539,9 +1777,20 @@ static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root root_item->drop_level = i; return 0; } else { + if (path->nodes[*level] == root->node) { + root_owner = root->root_key.objectid; + root_gen = + btrfs_header_generation(path->nodes[*level]); + } else { + struct extent_buffer *node; + node = path->nodes[*level + 1]; + root_owner = btrfs_header_owner(node); + root_gen = btrfs_header_generation(node); + } ret = btrfs_free_extent(trans, root, path->nodes[*level]->start, - path->nodes[*level]->len, 1); + path->nodes[*level]->len, + root_owner, root_gen, 0, 0, 1); BUG_ON(ret); free_extent_buffer(path->nodes[*level]); path->nodes[*level] = NULL; |