static int change_extents_uuid(struct btrfs_fs_info *fs_info) { struct btrfs_root *root = fs_info->extent_root; struct btrfs_path path; struct btrfs_key key = {0, 0, 0}; int ret = 0; btrfs_init_path(&path); /* * Here we don't use transaction as it will takes a lot of reserve * space, and that will make a near-full btrfs unable to change uuid */ ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0); if (ret < 0) goto out; while (1) { struct btrfs_extent_item *ei; struct extent_buffer *eb; u64 flags; u64 bytenr; btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); if (key.type != BTRFS_EXTENT_ITEM_KEY && key.type != BTRFS_METADATA_ITEM_KEY) goto next; ei = btrfs_item_ptr(path.nodes[0], path.slots[0], struct btrfs_extent_item); flags = btrfs_extent_flags(path.nodes[0], ei); if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) goto next; bytenr = key.objectid; eb = read_tree_block(root, bytenr, root->nodesize, 0); if (IS_ERR(eb)) { error("failed to read tree block: %llu", bytenr); ret = PTR_ERR(eb); goto out; } ret = change_header_uuid(root, eb); free_extent_buffer(eb); if (ret < 0) { error("failed to change uuid of tree block: %llu", bytenr); goto out; } next: ret = btrfs_next_item(root, &path); if (ret < 0) goto out; if (ret > 0) { ret = 0; goto out; } } out: btrfs_release_path(&path); return ret; }
/* * helper function to iterate extent inline refs. ptr must point to a 0 value * for the first call and may be modified. it is used to track state. * if more refs exist, 0 is returned and the next call to * __get_extent_inline_ref must pass the modified ptr parameter to get the * next ref. after the last ref was processed, 1 is returned. * returns <0 on error */ static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb, struct btrfs_extent_item *ei, u32 item_size, struct btrfs_extent_inline_ref **out_eiref, int *out_type) { unsigned long end; u64 flags; struct btrfs_tree_block_info *info; if (!*ptr) { /* first call */ flags = btrfs_extent_flags(eb, ei); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { info = (struct btrfs_tree_block_info *)(ei + 1); *out_eiref = (struct btrfs_extent_inline_ref *)(info + 1); } else { *out_eiref = (struct btrfs_extent_inline_ref *)(ei + 1); } *ptr = (unsigned long)*out_eiref; if ((void *)*ptr >= (void *)ei + item_size) return -ENOENT; } end = (unsigned long)ei + item_size; *out_eiref = (struct btrfs_extent_inline_ref *)*ptr; *out_type = btrfs_extent_inline_ref_type(eb, *out_eiref); *ptr += btrfs_extent_inline_ref_size(*out_type); WARN_ON(*ptr > end); if (*ptr == end) return 1; /* last */ return 0; }
/* * this makes the path point to (logical EXTENT_ITEM *) * returns BTRFS_EXTENT_FLAG_DATA for data, BTRFS_EXTENT_FLAG_TREE_BLOCK for * tree blocks and <0 on error. */ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, struct btrfs_path *path, struct btrfs_key *found_key, u64 *flags_ret) { int ret; u64 flags; u32 item_size; struct extent_buffer *eb; struct btrfs_extent_item *ei; struct btrfs_key key; key.type = BTRFS_EXTENT_ITEM_KEY; key.objectid = logical; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0); if (ret < 0) return ret; ret = btrfs_previous_item(fs_info->extent_root, path, 0, BTRFS_EXTENT_ITEM_KEY); if (ret < 0) return ret; btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]); if (found_key->type != BTRFS_EXTENT_ITEM_KEY || found_key->objectid > logical || found_key->objectid + found_key->offset <= logical) { pr_debug("logical %llu is not within any extent\n", (unsigned long long)logical); return -ENOENT; } eb = path->nodes[0]; item_size = btrfs_item_size_nr(eb, path->slots[0]); BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); flags = btrfs_extent_flags(eb, ei); pr_debug("logical %llu is at position %llu within the extent (%llu " "EXTENT_ITEM %llu) flags %#llx size %u\n", (unsigned long long)logical, (unsigned long long)(logical - found_key->objectid), (unsigned long long)found_key->objectid, (unsigned long long)found_key->offset, (unsigned long long)flags, item_size); WARN_ON(!flags_ret); if (flags_ret) { if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) *flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK; else if (flags & BTRFS_EXTENT_FLAG_DATA) *flags_ret = BTRFS_EXTENT_FLAG_DATA; else BUG_ON(1); return 0; } return -EIO; }
/* * helper function to iterate extent inline refs. ptr must point to a 0 value * for the first call and may be modified. it is used to track state. * if more refs exist, 0 is returned and the next call to * __get_extent_inline_ref must pass the modified ptr parameter to get the * next ref. after the last ref was processed, 1 is returned. * returns <0 on error */ static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb, struct btrfs_key *key, struct btrfs_extent_item *ei, u32 item_size, struct btrfs_extent_inline_ref **out_eiref, int *out_type) { unsigned long end; u64 flags; struct btrfs_tree_block_info *info; if (!*ptr) { /* first call */ flags = btrfs_extent_flags(eb, ei); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { if (key->type == BTRFS_METADATA_ITEM_KEY) { /* a skinny metadata extent */ *out_eiref = (struct btrfs_extent_inline_ref *)(ei + 1); } else { WARN_ON(key->type != BTRFS_EXTENT_ITEM_KEY); info = (struct btrfs_tree_block_info *)(ei + 1); *out_eiref = (struct btrfs_extent_inline_ref *)(info + 1); } } else { *out_eiref = (struct btrfs_extent_inline_ref *)(ei + 1); } *ptr = (unsigned long)*out_eiref; if ((unsigned long)(*ptr) >= (unsigned long)ei + item_size) return -ENOENT; } end = (unsigned long)ei + item_size; *out_eiref = (struct btrfs_extent_inline_ref *)(*ptr); *out_type = btrfs_extent_inline_ref_type(eb, *out_eiref); *ptr += btrfs_extent_inline_ref_size(*out_type); WARN_ON(*ptr > end); if (*ptr == end) return 1; /* last */ return 0; }
/* * this makes the path point to (logical EXTENT_ITEM *) * returns BTRFS_EXTENT_FLAG_DATA for data, BTRFS_EXTENT_FLAG_TREE_BLOCK for * tree blocks and <0 on error. */ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, struct btrfs_path *path, struct btrfs_key *found_key) { int ret; u64 flags; u32 item_size; struct extent_buffer *eb; struct btrfs_extent_item *ei; struct btrfs_key key; key.type = BTRFS_EXTENT_ITEM_KEY; key.objectid = logical; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0); if (ret < 0) return ret; ret = btrfs_previous_item(fs_info->extent_root, path, 0, BTRFS_EXTENT_ITEM_KEY); if (ret < 0) return ret; btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]); if (found_key->type != BTRFS_EXTENT_ITEM_KEY || found_key->objectid > logical || found_key->objectid + found_key->offset <= logical) return -ENOENT; eb = path->nodes[0]; item_size = btrfs_item_size_nr(eb, path->slots[0]); BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); flags = btrfs_extent_flags(eb, ei); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) return BTRFS_EXTENT_FLAG_TREE_BLOCK; if (flags & BTRFS_EXTENT_FLAG_DATA) return BTRFS_EXTENT_FLAG_DATA; return -EIO; }
static void print_extent_item(struct extent_buffer *eb, int slot, int metadata) { struct btrfs_extent_item *ei; struct btrfs_extent_inline_ref *iref; struct btrfs_extent_data_ref *dref; struct btrfs_shared_data_ref *sref; struct btrfs_disk_key key; unsigned long end; unsigned long ptr; int type; u32 item_size = btrfs_item_size_nr(eb, slot); u64 flags; u64 offset; if (item_size < sizeof(*ei)) { #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 struct btrfs_extent_item_v0 *ei0; BUG_ON(item_size != sizeof(*ei0)); ei0 = btrfs_item_ptr(eb, slot, struct btrfs_extent_item_v0); printf("\t\textent refs %u\n", btrfs_extent_refs_v0(eb, ei0)); return; #else BUG(); #endif } ei = btrfs_item_ptr(eb, slot, struct btrfs_extent_item); flags = btrfs_extent_flags(eb, ei); printf("\t\textent refs %llu gen %llu flags %llu\n", (unsigned long long)btrfs_extent_refs(eb, ei), (unsigned long long)btrfs_extent_generation(eb, ei), (unsigned long long)flags); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !metadata) { struct btrfs_tree_block_info *info; info = (struct btrfs_tree_block_info *)(ei + 1); btrfs_tree_block_key(eb, info, &key); printf("\t\ttree block "); btrfs_print_key(&key); printf(" level %d\n", btrfs_tree_block_level(eb, info)); iref = (struct btrfs_extent_inline_ref *)(info + 1); } else if (metadata) { struct btrfs_key tmp; btrfs_item_key_to_cpu(eb, &tmp, slot); printf("\t\ttree block skinny level %d\n", (int)tmp.offset); iref = (struct btrfs_extent_inline_ref *)(ei + 1); } else{ iref = (struct btrfs_extent_inline_ref *)(ei + 1); } ptr = (unsigned long)iref; end = (unsigned long)ei + item_size; while (ptr < end) { iref = (struct btrfs_extent_inline_ref *)ptr; type = btrfs_extent_inline_ref_type(eb, iref); offset = btrfs_extent_inline_ref_offset(eb, iref); switch (type) { case BTRFS_TREE_BLOCK_REF_KEY: printf("\t\ttree block backref root %llu\n", (unsigned long long)offset); break; case BTRFS_SHARED_BLOCK_REF_KEY: printf("\t\tshared block backref parent %llu\n", (unsigned long long)offset); break; case BTRFS_EXTENT_DATA_REF_KEY: dref = (struct btrfs_extent_data_ref *)(&iref->offset); printf("\t\textent data backref root %llu " "objectid %llu offset %llu count %u\n", (unsigned long long)btrfs_extent_data_ref_root(eb, dref), (unsigned long long)btrfs_extent_data_ref_objectid(eb, dref), (unsigned long long)btrfs_extent_data_ref_offset(eb, dref), btrfs_extent_data_ref_count(eb, dref)); break; case BTRFS_SHARED_DATA_REF_KEY: sref = (struct btrfs_shared_data_ref *)(iref + 1); printf("\t\tshared data backref parent %llu count %u\n", (unsigned long long)offset, btrfs_shared_data_ref_count(eb, sref)); break; default: return; } ptr += btrfs_extent_inline_ref_size(type); } WARN_ON(ptr > end); }
/* * add all inline backrefs for bytenr to the list */ static int __add_inline_refs(struct btrfs_fs_info *fs_info, struct btrfs_path *path, u64 bytenr, int *info_level, struct list_head *prefs) { int ret = 0; int slot; struct extent_buffer *leaf; struct btrfs_key key; struct btrfs_key found_key; unsigned long ptr; unsigned long end; struct btrfs_extent_item *ei; u64 flags; u64 item_size; /* * enumerate all inline refs */ leaf = path->nodes[0]; slot = path->slots[0]; item_size = btrfs_item_size_nr(leaf, slot); BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); flags = btrfs_extent_flags(leaf, ei); btrfs_item_key_to_cpu(leaf, &found_key, slot); ptr = (unsigned long)(ei + 1); end = (unsigned long)ei + item_size; if (found_key.type == BTRFS_EXTENT_ITEM_KEY && flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { struct btrfs_tree_block_info *info; info = (struct btrfs_tree_block_info *)ptr; *info_level = btrfs_tree_block_level(leaf, info); ptr += sizeof(struct btrfs_tree_block_info); BUG_ON(ptr > end); } else if (found_key.type == BTRFS_METADATA_ITEM_KEY) { *info_level = found_key.offset; } else { BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA)); } while (ptr < end) { struct btrfs_extent_inline_ref *iref; u64 offset; int type; iref = (struct btrfs_extent_inline_ref *)ptr; type = btrfs_extent_inline_ref_type(leaf, iref); offset = btrfs_extent_inline_ref_offset(leaf, iref); switch (type) { case BTRFS_SHARED_BLOCK_REF_KEY: ret = __add_prelim_ref(prefs, 0, NULL, *info_level + 1, offset, bytenr, 1); break; case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_shared_data_ref *sdref; int count; sdref = (struct btrfs_shared_data_ref *)(iref + 1); count = btrfs_shared_data_ref_count(leaf, sdref); ret = __add_prelim_ref(prefs, 0, NULL, 0, offset, bytenr, count); break; } case BTRFS_TREE_BLOCK_REF_KEY: ret = __add_prelim_ref(prefs, offset, NULL, *info_level + 1, 0, bytenr, 1); break; case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_extent_data_ref *dref; int count; u64 root; dref = (struct btrfs_extent_data_ref *)(&iref->offset); count = btrfs_extent_data_ref_count(leaf, dref); key.objectid = btrfs_extent_data_ref_objectid(leaf, dref); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = btrfs_extent_data_ref_offset(leaf, dref); root = btrfs_extent_data_ref_root(leaf, dref); ret = __add_prelim_ref(prefs, root, &key, 0, 0, bytenr, count); break; } default: WARN_ON(1); } if (ret) return ret; ptr += btrfs_extent_inline_ref_size(type); } return 0; }
/* * this makes the path point to (logical EXTENT_ITEM *) * returns BTRFS_EXTENT_FLAG_DATA for data, BTRFS_EXTENT_FLAG_TREE_BLOCK for * tree blocks and <0 on error. */ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, struct btrfs_path *path, struct btrfs_key *found_key, u64 *flags_ret) { int ret; u64 flags; u64 size = 0; u32 item_size; struct extent_buffer *eb; struct btrfs_extent_item *ei; struct btrfs_key key; if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) key.type = BTRFS_METADATA_ITEM_KEY; else key.type = BTRFS_EXTENT_ITEM_KEY; key.objectid = logical; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0); if (ret < 0) return ret; while (1) { u32 nritems; if (path->slots[0] == 0) { btrfs_set_path_blocking(path); ret = btrfs_prev_leaf(fs_info->extent_root, path); if (ret != 0) { if (ret > 0) { pr_debug("logical %llu is not within " "any extent\n", logical); ret = -ENOENT; } return ret; } } else { path->slots[0]--; } nritems = btrfs_header_nritems(path->nodes[0]); if (nritems == 0) { pr_debug("logical %llu is not within any extent\n", logical); return -ENOENT; } if (path->slots[0] == nritems) path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]); if (found_key->type == BTRFS_EXTENT_ITEM_KEY || found_key->type == BTRFS_METADATA_ITEM_KEY) break; } if (found_key->type == BTRFS_METADATA_ITEM_KEY) size = fs_info->extent_root->leafsize; else if (found_key->type == BTRFS_EXTENT_ITEM_KEY) size = found_key->offset; if (found_key->objectid > logical || found_key->objectid + size <= logical) { pr_debug("logical %llu is not within any extent\n", logical); return -ENOENT; } eb = path->nodes[0]; item_size = btrfs_item_size_nr(eb, path->slots[0]); BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); flags = btrfs_extent_flags(eb, ei); pr_debug("logical %llu is at position %llu within the extent (%llu " "EXTENT_ITEM %llu) flags %#llx size %u\n", logical, logical - found_key->objectid, found_key->objectid, found_key->offset, flags, item_size); WARN_ON(!flags_ret); if (flags_ret) { if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) *flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK; else if (flags & BTRFS_EXTENT_FLAG_DATA) *flags_ret = BTRFS_EXTENT_FLAG_DATA; else BUG_ON(1); return 0; } return -EIO; }
static void print_extent_item(struct extent_buffer *eb, int slot, int type) { struct btrfs_extent_item *ei; struct btrfs_extent_inline_ref *iref; struct btrfs_extent_data_ref *dref; struct btrfs_shared_data_ref *sref; struct btrfs_disk_key key; unsigned long end; unsigned long ptr; u32 item_size = btrfs_item_size_nr(eb, slot); u64 flags; u64 offset; if (item_size < sizeof(*ei)) { #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 struct btrfs_extent_item_v0 *ei0; BUG_ON(item_size != sizeof(*ei0)); ei0 = btrfs_item_ptr(eb, slot, struct btrfs_extent_item_v0); printk(KERN_INFO "\t\textent refs %u\n", btrfs_extent_refs_v0(eb, ei0)); return; #else BUG(); #endif } ei = btrfs_item_ptr(eb, slot, struct btrfs_extent_item); flags = btrfs_extent_flags(eb, ei); printk(KERN_INFO "\t\textent refs %llu gen %llu flags %llu\n", btrfs_extent_refs(eb, ei), btrfs_extent_generation(eb, ei), flags); if ((type == BTRFS_EXTENT_ITEM_KEY) && flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { struct btrfs_tree_block_info *info; info = (struct btrfs_tree_block_info *)(ei + 1); btrfs_tree_block_key(eb, info, &key); printk(KERN_INFO "\t\ttree block key (%llu %u %llu) " "level %d\n", btrfs_disk_key_objectid(&key), key.type, btrfs_disk_key_offset(&key), btrfs_tree_block_level(eb, info)); iref = (struct btrfs_extent_inline_ref *)(info + 1); } else { iref = (struct btrfs_extent_inline_ref *)(ei + 1); } ptr = (unsigned long)iref; end = (unsigned long)ei + item_size; while (ptr < end) { iref = (struct btrfs_extent_inline_ref *)ptr; type = btrfs_extent_inline_ref_type(eb, iref); offset = btrfs_extent_inline_ref_offset(eb, iref); switch (type) { case BTRFS_TREE_BLOCK_REF_KEY: printk(KERN_INFO "\t\ttree block backref " "root %llu\n", offset); break; case BTRFS_SHARED_BLOCK_REF_KEY: printk(KERN_INFO "\t\tshared block backref " "parent %llu\n", offset); break; case BTRFS_EXTENT_DATA_REF_KEY: dref = (struct btrfs_extent_data_ref *)(&iref->offset); print_extent_data_ref(eb, dref); break; case BTRFS_SHARED_DATA_REF_KEY: sref = (struct btrfs_shared_data_ref *)(iref + 1); printk(KERN_INFO "\t\tshared data backref " "parent %llu count %u\n", offset, btrfs_shared_data_ref_count(eb, sref)); break; default: BUG(); } ptr += btrfs_extent_inline_ref_size(type); } WARN_ON(ptr > end); }