From 57f24f10733ac57754d4eae3666919480718b032 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 24 Jun 2020 18:03:00 +0200 Subject: [PATCH] fs: btrfs: Crossport btrfs_read_sys_array() and btrfs_read_chunk_tree() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit These two functions play a big role in btrfs bootstrap. The following function is removed: - Seed device support Although in theory we can still support multiple devices, we don't have a facility in U-Boot to do device scan without opening them. Signed-off-by: Qu Wenruo Reviewed-by: Marek Behún --- fs/btrfs/btrfs.c | 2 +- fs/btrfs/btrfs.h | 2 +- fs/btrfs/chunk-map.c | 2 +- fs/btrfs/volumes.c | 301 +++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/volumes.h | 2 + 5 files changed, 306 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/btrfs.c b/fs/btrfs/btrfs.c index b4535c9551..f5266f1b91 100644 --- a/fs/btrfs/btrfs.c +++ b/fs/btrfs/btrfs.c @@ -100,7 +100,7 @@ int btrfs_probe(struct blk_desc *fs_dev_desc, btrfs_info.chunk_root.objectid = 0; btrfs_info.chunk_root.bytenr = btrfs_info.sb.chunk_root; - if (btrfs_read_chunk_tree()) { + if (__btrfs_read_chunk_tree()) { printf("%s: failed to read chunk tree\n", __func__); return -1; } diff --git a/fs/btrfs/btrfs.h b/fs/btrfs/btrfs.h index ae29226e9a..7dfdaf77ba 100644 --- a/fs/btrfs/btrfs.h +++ b/fs/btrfs/btrfs.h @@ -33,7 +33,7 @@ int btrfs_devread(u64, int, void *); u64 btrfs_map_logical_to_physical(u64); int btrfs_chunk_map_init(void); void btrfs_chunk_map_exit(void); -int btrfs_read_chunk_tree(void); +int __btrfs_read_chunk_tree(void); /* compression.c */ u32 btrfs_decompress(u8 type, const char *, u32, char *, u32); diff --git a/fs/btrfs/chunk-map.c b/fs/btrfs/chunk-map.c index 8e3d13c4a9..bff83e4dc8 100644 --- a/fs/btrfs/chunk-map.c +++ b/fs/btrfs/chunk-map.c @@ -142,7 +142,7 @@ int btrfs_chunk_map_init(void) return 0; } -int btrfs_read_chunk_tree(void) +int __btrfs_read_chunk_tree(void) { struct __btrfs_path path; struct btrfs_key key, *found_key; diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index c671b53426..fcf52d4b0f 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -5,6 +5,7 @@ #include "ctree.h" #include "disk-io.h" #include "volumes.h" +#include "extent-io.h" const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { [BTRFS_RAID_RAID10] = { @@ -369,6 +370,14 @@ struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, return NULL; } +static struct btrfs_device *fill_missing_device(u64 devid) +{ + struct btrfs_device *device; + + device = kzalloc(sizeof(*device), GFP_NOFS); + return device; +} + /* * slot == -1: SYSTEM chunk * return -EIO on error, otherwise return 0 @@ -498,6 +507,298 @@ int btrfs_check_chunk_valid(struct btrfs_fs_info *fs_info, return 0; } +/* + * Slot is used to verify the chunk item is valid + * + * For sys chunk in superblock, pass -1 to indicate sys chunk. + */ +static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key, + struct extent_buffer *leaf, + struct btrfs_chunk *chunk, int slot) +{ + struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; + struct map_lookup *map; + struct cache_extent *ce; + u64 logical; + u64 length; + u64 devid; + u8 uuid[BTRFS_UUID_SIZE]; + int num_stripes; + int ret; + int i; + + logical = key->offset; + length = btrfs_chunk_length(leaf, chunk); + num_stripes = btrfs_chunk_num_stripes(leaf, chunk); + /* Validation check */ + ret = btrfs_check_chunk_valid(fs_info, leaf, chunk, slot, logical); + if (ret) { + error("%s checksums match, but it has an invalid chunk, %s", + (slot == -1) ? "Superblock" : "Metadata", + (slot == -1) ? "try btrfsck --repair -s ie, 0,1,2" : ""); + return ret; + } + + ce = search_cache_extent(&map_tree->cache_tree, logical); + + /* already mapped? */ + if (ce && ce->start <= logical && ce->start + ce->size > logical) { + return 0; + } + + map = kmalloc(btrfs_map_lookup_size(num_stripes), GFP_NOFS); + if (!map) + return -ENOMEM; + + map->ce.start = logical; + map->ce.size = length; + map->num_stripes = num_stripes; + map->io_width = btrfs_chunk_io_width(leaf, chunk); + map->io_align = btrfs_chunk_io_align(leaf, chunk); + map->sector_size = btrfs_chunk_sector_size(leaf, chunk); + map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); + map->type = btrfs_chunk_type(leaf, chunk); + map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); + + for (i = 0; i < num_stripes; i++) { + map->stripes[i].physical = + btrfs_stripe_offset_nr(leaf, chunk, i); + devid = btrfs_stripe_devid_nr(leaf, chunk, i); + read_extent_buffer(leaf, uuid, (unsigned long) + btrfs_stripe_dev_uuid_nr(chunk, i), + BTRFS_UUID_SIZE); + map->stripes[i].dev = btrfs_find_device(fs_info, devid, uuid, + NULL); + if (!map->stripes[i].dev) { + map->stripes[i].dev = fill_missing_device(devid); + printf("warning, device %llu is missing\n", + (unsigned long long)devid); + list_add(&map->stripes[i].dev->dev_list, + &fs_info->fs_devices->devices); + } + + } + ret = insert_cache_extent(&map_tree->cache_tree, &map->ce); + if (ret < 0) { + errno = -ret; + error("failed to add chunk map start=%llu len=%llu: %d (%m)", + map->ce.start, map->ce.size, ret); + } + + return ret; +} + +static int fill_device_from_item(struct extent_buffer *leaf, + struct btrfs_dev_item *dev_item, + struct btrfs_device *device) +{ + unsigned long ptr; + + device->devid = btrfs_device_id(leaf, dev_item); + device->total_bytes = btrfs_device_total_bytes(leaf, dev_item); + device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); + device->type = btrfs_device_type(leaf, dev_item); + device->io_align = btrfs_device_io_align(leaf, dev_item); + device->io_width = btrfs_device_io_width(leaf, dev_item); + device->sector_size = btrfs_device_sector_size(leaf, dev_item); + + ptr = (unsigned long)btrfs_device_uuid(dev_item); + read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); + + return 0; +} + +static int read_one_dev(struct btrfs_fs_info *fs_info, + struct extent_buffer *leaf, + struct btrfs_dev_item *dev_item) +{ + struct btrfs_device *device; + u64 devid; + int ret = 0; + u8 fs_uuid[BTRFS_UUID_SIZE]; + u8 dev_uuid[BTRFS_UUID_SIZE]; + + devid = btrfs_device_id(leaf, dev_item); + read_extent_buffer(leaf, dev_uuid, + (unsigned long)btrfs_device_uuid(dev_item), + BTRFS_UUID_SIZE); + read_extent_buffer(leaf, fs_uuid, + (unsigned long)btrfs_device_fsid(dev_item), + BTRFS_FSID_SIZE); + + if (memcmp(fs_uuid, fs_info->fs_devices->fsid, BTRFS_UUID_SIZE)) { + error("Seed device is not yet supported\n"); + return -ENOTSUPP; + } + + device = btrfs_find_device(fs_info, devid, dev_uuid, fs_uuid); + if (!device) { + device = kzalloc(sizeof(*device), GFP_NOFS); + if (!device) + return -ENOMEM; + list_add(&device->dev_list, + &fs_info->fs_devices->devices); + } + + fill_device_from_item(leaf, dev_item, device); + fs_info->fs_devices->total_rw_bytes += + btrfs_device_total_bytes(leaf, dev_item); + return ret; +} + +int btrfs_read_sys_array(struct btrfs_fs_info *fs_info) +{ + struct btrfs_super_block *super_copy = fs_info->super_copy; + struct extent_buffer *sb; + struct btrfs_disk_key *disk_key; + struct btrfs_chunk *chunk; + u8 *array_ptr; + unsigned long sb_array_offset; + int ret = 0; + u32 num_stripes; + u32 array_size; + u32 len = 0; + u32 cur_offset; + struct btrfs_key key; + + if (fs_info->nodesize < BTRFS_SUPER_INFO_SIZE) { + printf("ERROR: nodesize %u too small to read superblock\n", + fs_info->nodesize); + return -EINVAL; + } + sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET, + BTRFS_SUPER_INFO_SIZE); + if (!sb) + return -ENOMEM; + btrfs_set_buffer_uptodate(sb); + write_extent_buffer(sb, super_copy, 0, sizeof(*super_copy)); + array_size = btrfs_super_sys_array_size(super_copy); + + array_ptr = super_copy->sys_chunk_array; + sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array); + cur_offset = 0; + + while (cur_offset < array_size) { + disk_key = (struct btrfs_disk_key *)array_ptr; + len = sizeof(*disk_key); + if (cur_offset + len > array_size) + goto out_short_read; + + btrfs_disk_key_to_cpu(&key, disk_key); + + array_ptr += len; + sb_array_offset += len; + cur_offset += len; + + if (key.type == BTRFS_CHUNK_ITEM_KEY) { + chunk = (struct btrfs_chunk *)sb_array_offset; + /* + * At least one btrfs_chunk with one stripe must be + * present, exact stripe count check comes afterwards + */ + len = btrfs_chunk_item_size(1); + if (cur_offset + len > array_size) + goto out_short_read; + + num_stripes = btrfs_chunk_num_stripes(sb, chunk); + if (!num_stripes) { + printk( + "ERROR: invalid number of stripes %u in sys_array at offset %u\n", + num_stripes, cur_offset); + ret = -EIO; + break; + } + + len = btrfs_chunk_item_size(num_stripes); + if (cur_offset + len > array_size) + goto out_short_read; + + ret = read_one_chunk(fs_info, &key, sb, chunk, -1); + if (ret) + break; + } else { + printk( + "ERROR: unexpected item type %u in sys_array at offset %u\n", + (u32)key.type, cur_offset); + ret = -EIO; + break; + } + array_ptr += len; + sb_array_offset += len; + cur_offset += len; + } + free_extent_buffer(sb); + return ret; + +out_short_read: + printk("ERROR: sys_array too short to read %u bytes at offset %u\n", + len, cur_offset); + free_extent_buffer(sb); + return -EIO; +} + +int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info) +{ + struct btrfs_path *path; + struct extent_buffer *leaf; + struct btrfs_key key; + struct btrfs_key found_key; + struct btrfs_root *root = fs_info->chunk_root; + int ret; + int slot; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + /* + * Read all device items, and then all the chunk items. All + * device items are found before any chunk item (their object id + * is smaller than the lowest possible object id for a chunk + * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID). + */ + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.offset = 0; + key.type = 0; + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto error; + while(1) { + leaf = path->nodes[0]; + slot = path->slots[0]; + if (slot >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root, path); + if (ret == 0) + continue; + if (ret < 0) + goto error; + break; + } + btrfs_item_key_to_cpu(leaf, &found_key, slot); + if (found_key.type == BTRFS_DEV_ITEM_KEY) { + struct btrfs_dev_item *dev_item; + dev_item = btrfs_item_ptr(leaf, slot, + struct btrfs_dev_item); + ret = read_one_dev(fs_info, leaf, dev_item); + if (ret < 0) + goto error; + } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { + struct btrfs_chunk *chunk; + chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); + ret = read_one_chunk(fs_info, &found_key, leaf, chunk, + slot); + if (ret < 0) + goto error; + } + path->slots[0]++; + } + + ret = 0; +error: + btrfs_free_path(path); + return ret; +} + /* * Get stripe length from chunk item and its stripe items * diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 32e39382a8..9d1a07ae78 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -182,6 +182,8 @@ static inline int btrfs_next_bg_system(struct btrfs_fs_info *fs_info, return btrfs_next_bg(fs_info, logical, size, BTRFS_BLOCK_GROUP_SYSTEM); } +int btrfs_read_sys_array(struct btrfs_fs_info *fs_info); +int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info); int btrfs_open_devices(struct btrfs_fs_devices *fs_devices); int btrfs_close_devices(struct btrfs_fs_devices *fs_devices); void btrfs_close_all_devices(void); -- 2.39.5