diff options
Diffstat (limited to 'fs/btrfs/disk-io.c')
| -rw-r--r-- | fs/btrfs/disk-io.c | 4846 |
1 files changed, 4846 insertions, 0 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c new file mode 100644 index 000000000..0e25a3f64 --- /dev/null +++ b/fs/btrfs/disk-io.c @@ -0,0 +1,4846 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2007 Oracle. All rights reserved. + */ + +#include <linux/fs.h> +#include <linux/blkdev.h> +#include <linux/radix-tree.h> +#include <linux/writeback.h> +#include <linux/workqueue.h> +#include <linux/kthread.h> +#include <linux/slab.h> +#include <linux/migrate.h> +#include <linux/ratelimit.h> +#include <linux/uuid.h> +#include <linux/semaphore.h> +#include <linux/error-injection.h> +#include <linux/crc32c.h> +#include <linux/sched/mm.h> +#include <asm/unaligned.h> +#include <crypto/hash.h> +#include "ctree.h" +#include "disk-io.h" +#include "transaction.h" +#include "btrfs_inode.h" +#include "volumes.h" +#include "print-tree.h" +#include "locking.h" +#include "tree-log.h" +#include "free-space-cache.h" +#include "free-space-tree.h" +#include "inode-map.h" +#include "check-integrity.h" +#include "rcu-string.h" +#include "dev-replace.h" +#include "raid56.h" +#include "sysfs.h" +#include "qgroup.h" +#include "compression.h" +#include "tree-checker.h" +#include "ref-verify.h" +#include "block-group.h" +#include "discard.h" +#include "space-info.h" + +#define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\ + BTRFS_HEADER_FLAG_RELOC |\ + BTRFS_SUPER_FLAG_ERROR |\ + BTRFS_SUPER_FLAG_SEEDING |\ + BTRFS_SUPER_FLAG_METADUMP |\ + BTRFS_SUPER_FLAG_METADUMP_V2) + +static void end_workqueue_fn(struct btrfs_work *work); +static void btrfs_destroy_ordered_extents(struct btrfs_root *root); +static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans, + struct btrfs_fs_info *fs_info); +static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root); +static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info, + struct extent_io_tree *dirty_pages, + int mark); +static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info, + struct extent_io_tree *pinned_extents); +static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info); +static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info); + +/* + * btrfs_end_io_wq structs are used to do processing in task context when an IO + * is complete. This is used during reads to verify checksums, and it is used + * by writes to insert metadata for new file extents after IO is complete. + */ +struct btrfs_end_io_wq { + struct bio *bio; + bio_end_io_t *end_io; + void *private; + struct btrfs_fs_info *info; + blk_status_t status; + enum btrfs_wq_endio_type metadata; + struct btrfs_work work; +}; + +static struct kmem_cache *btrfs_end_io_wq_cache; + +int __init btrfs_end_io_wq_init(void) +{ + btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq", + sizeof(struct btrfs_end_io_wq), + 0, + SLAB_MEM_SPREAD, + NULL); + if (!btrfs_end_io_wq_cache) + return -ENOMEM; + return 0; +} + +void __cold btrfs_end_io_wq_exit(void) +{ + kmem_cache_destroy(btrfs_end_io_wq_cache); +} + +static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info) +{ + if (fs_info->csum_shash) + crypto_free_shash(fs_info->csum_shash); +} + +/* + * async submit bios are used to offload expensive checksumming + * onto the worker threads. They checksum file and metadata bios + * just before they are sent down the IO stack. + */ +struct async_submit_bio { + void *private_data; + struct bio *bio; + extent_submit_bio_start_t *submit_bio_start; + int mirror_num; + /* + * bio_offset is optional, can be used if the pages in the bio + * can't tell us where in the file the bio should go + */ + u64 bio_offset; + struct btrfs_work work; + blk_status_t status; +}; + +/* + * Lockdep class keys for extent_buffer->lock's in this root. For a given + * eb, the lockdep key is determined by the btrfs_root it belongs to and + * the level the eb occupies in the tree. + * + * Different roots are used for different purposes and may nest inside each + * other and they require separate keysets. As lockdep keys should be + * static, assign keysets according to the purpose of the root as indicated + * by btrfs_root->root_key.objectid. This ensures that all special purpose + * roots have separate keysets. + * + * Lock-nesting across peer nodes is always done with the immediate parent + * node locked thus preventing deadlock. As lockdep doesn't know this, use + * subclass to avoid triggering lockdep warning in such cases. + * + * The key is set by the readpage_end_io_hook after the buffer has passed + * csum validation but before the pages are unlocked. It is also set by + * btrfs_init_new_buffer on freshly allocated blocks. + * + * We also add a check to make sure the highest level of the tree is the + * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code + * needs update as well. + */ +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# if BTRFS_MAX_LEVEL != 8 +# error +# endif + +static struct btrfs_lockdep_keyset { + u64 id; /* root objectid */ + const char *name_stem; /* lock name stem */ + char names[BTRFS_MAX_LEVEL + 1][20]; + struct lock_class_key keys[BTRFS_MAX_LEVEL + 1]; +} btrfs_lockdep_keysets[] = { + { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" }, + { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" }, + { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" }, + { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" }, + { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" }, + { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" }, + { .id = BTRFS_QUOTA_TREE_OBJECTID, .name_stem = "quota" }, + { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" }, + { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" }, + { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" }, + { .id = BTRFS_UUID_TREE_OBJECTID, .name_stem = "uuid" }, + { .id = BTRFS_FREE_SPACE_TREE_OBJECTID, .name_stem = "free-space" }, + { .id = 0, .name_stem = "tree" }, +}; + +void __init btrfs_init_lockdep(void) +{ + int i, j; + + /* initialize lockdep class names */ + for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) { + struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i]; + + for (j = 0; j < ARRAY_SIZE(ks->names); j++) + snprintf(ks->names[j], sizeof(ks->names[j]), + "btrfs-%s-%02d", ks->name_stem, j); + } +} + +void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, + int level) +{ + struct btrfs_lockdep_keyset *ks; + + BUG_ON(level >= ARRAY_SIZE(ks->keys)); + + /* find the matching keyset, id 0 is the default entry */ + for (ks = btrfs_lockdep_keysets; ks->id; ks++) + if (ks->id == objectid) + break; + + lockdep_set_class_and_name(&eb->lock, + &ks->keys[level], ks->names[level]); +} + +#endif + +/* + * Compute the csum of a btree block and store the result to provided buffer. + */ +static void csum_tree_block(struct extent_buffer *buf, u8 *result) +{ + struct btrfs_fs_info *fs_info = buf->fs_info; + const int num_pages = fs_info->nodesize >> PAGE_SHIFT; + SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); + char *kaddr; + int i; + + shash->tfm = fs_info->csum_shash; + crypto_shash_init(shash); + kaddr = page_address(buf->pages[0]); + crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE, + PAGE_SIZE - BTRFS_CSUM_SIZE); + + for (i = 1; i < num_pages && INLINE_EXTENT_BUFFER_PAGES > 1; i++) { + kaddr = page_address(buf->pages[i]); + crypto_shash_update(shash, kaddr, PAGE_SIZE); + } + memset(result, 0, BTRFS_CSUM_SIZE); + crypto_shash_final(shash, result); +} + +/* + * we can't consider a given block up to date unless the transid of the + * block matches the transid in the parent node's pointer. This is how we + * detect blocks that either didn't get written at all or got written + * in the wrong place. + */ +static int verify_parent_transid(struct extent_io_tree *io_tree, + struct extent_buffer *eb, u64 parent_transid, + int atomic) +{ + struct extent_state *cached_state = NULL; + int ret; + bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB); + + if (!parent_transid || btrfs_header_generation(eb) == parent_transid) + return 0; + + if (atomic) + return -EAGAIN; + + if (need_lock) { + btrfs_tree_read_lock(eb); + btrfs_set_lock_blocking_read(eb); + } + + lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1, + &cached_state); + if (extent_buffer_uptodate(eb) && + btrfs_header_generation(eb) == parent_transid) { + ret = 0; + goto out; + } + btrfs_err_rl(eb->fs_info, + "parent transid verify failed on %llu wanted %llu found %llu", + eb->start, + parent_transid, btrfs_header_generation(eb)); + ret = 1; + + /* + * Things reading via commit roots that don't have normal protection, + * like send, can have a really old block in cache that may point at a + * block that has been freed and re-allocated. So don't clear uptodate + * if we find an eb that is under IO (dirty/writeback) because we could + * end up reading in the stale data and then writing it back out and + * making everybody very sad. + */ + if (!extent_buffer_under_io(eb)) + clear_extent_buffer_uptodate(eb); +out: + unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1, + &cached_state); + if (need_lock) + btrfs_tree_read_unlock_blocking(eb); + return ret; +} + +static bool btrfs_supported_super_csum(u16 csum_type) +{ + switch (csum_type) { + case BTRFS_CSUM_TYPE_CRC32: + case BTRFS_CSUM_TYPE_XXHASH: + case BTRFS_CSUM_TYPE_SHA256: + case BTRFS_CSUM_TYPE_BLAKE2: + return true; + default: + return false; + } +} + +/* + * Return 0 if the superblock checksum type matches the checksum value of that + * algorithm. Pass the raw disk superblock data. + */ +static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info, + char *raw_disk_sb) +{ + struct btrfs_super_block *disk_sb = + (struct btrfs_super_block *)raw_disk_sb; + char result[BTRFS_CSUM_SIZE]; + SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); + + shash->tfm = fs_info->csum_shash; + + /* + * The super_block structure does not span the whole + * BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is + * filled with zeros and is included in the checksum. + */ + crypto_shash_digest(shash, raw_disk_sb + BTRFS_CSUM_SIZE, + BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result); + + if (memcmp(disk_sb->csum, result, btrfs_super_csum_size(disk_sb))) + return 1; + + return 0; +} + +int btrfs_verify_level_key(struct extent_buffer *eb, int level, + struct btrfs_key *first_key, u64 parent_transid) +{ + struct btrfs_fs_info *fs_info = eb->fs_info; + int found_level; + struct btrfs_key found_key; + int ret; + + found_level = btrfs_header_level(eb); + if (found_level != level) { + WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), + KERN_ERR "BTRFS: tree level check failed\n"); + btrfs_err(fs_info, +"tree level mismatch detected, bytenr=%llu level expected=%u has=%u", + eb->start, level, found_level); + return -EIO; + } + + if (!first_key) + return 0; + + /* + * For live tree block (new tree blocks in current transaction), + * we need proper lock context to avoid race, which is impossible here. + * So we only checks tree blocks which is read from disk, whose + * generation <= fs_info->last_trans_committed. + */ + if (btrfs_header_generation(eb) > fs_info->last_trans_committed) + return 0; + + /* We have @first_key, so this @eb must have at least one item */ + if (btrfs_header_nritems(eb) == 0) { + btrfs_err(fs_info, + "invalid tree nritems, bytenr=%llu nritems=0 expect >0", + eb->start); + WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG)); + return -EUCLEAN; + } + + if (found_level) + btrfs_node_key_to_cpu(eb, &found_key, 0); + else + btrfs_item_key_to_cpu(eb, &found_key, 0); + ret = btrfs_comp_cpu_keys(first_key, &found_key); + + if (ret) { + WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), + KERN_ERR "BTRFS: tree first key check failed\n"); + btrfs_err(fs_info, +"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)", + eb->start, parent_transid, first_key->objectid, + first_key->type, first_key->offset, + found_key.objectid, found_key.type, + found_key.offset); + } + return ret; +} + +/* + * helper to read a given tree block, doing retries as required when + * the checksums don't match and we have alternate mirrors to try. + * + * @parent_transid: expected transid, skip check if 0 + * @level: expected level, mandatory check + * @first_key: expected key of first slot, skip check if NULL + */ +static int btree_read_extent_buffer_pages(struct extent_buffer *eb, + u64 parent_transid, int level, + struct btrfs_key *first_key) +{ + struct btrfs_fs_info *fs_info = eb->fs_info; + struct extent_io_tree *io_tree; + int failed = 0; + int ret; + int num_copies = 0; + int mirror_num = 0; + int failed_mirror = 0; + + io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree; + while (1) { + clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags); + ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num); + if (!ret) { + if (verify_parent_transid(io_tree, eb, + parent_transid, 0)) + ret = -EIO; + else if (btrfs_verify_level_key(eb, level, + first_key, parent_transid)) + ret = -EUCLEAN; + else + break; + } + + num_copies = btrfs_num_copies(fs_info, + eb->start, eb->len); + if (num_copies == 1) + break; + + if (!failed_mirror) { + failed = 1; + failed_mirror = eb->read_mirror; + } + + mirror_num++; + if (mirror_num == failed_mirror) + mirror_num++; + + if (mirror_num > num_copies) + break; + } + + if (failed && !ret && failed_mirror) + btrfs_repair_eb_io_failure(eb, failed_mirror); + + return ret; +} + +/* + * checksum a dirty tree block before IO. This has extra checks to make sure + * we only fill in the checksum field in the first page of a multi-page block + */ + +static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page) +{ + u64 start = page_offset(page); + u64 found_start; + u8 result[BTRFS_CSUM_SIZE]; + u16 csum_size = btrfs_super_csum_size(fs_info->super_copy); + struct extent_buffer *eb; + int ret; + + eb = (struct extent_buffer *)page->private; + if (page != eb->pages[0]) + return 0; + + found_start = btrfs_header_bytenr(eb); + /* + * Please do not consolidate these warnings into a single if. + * It is useful to know what went wrong. + */ + if (WARN_ON(found_start != start)) + return -EUCLEAN; + if (WARN_ON(!PageUptodate(page))) + return -EUCLEAN; + + ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid, + offsetof(struct btrfs_header, fsid), + BTRFS_FSID_SIZE) == 0); + + csum_tree_block(eb, result); + + if (btrfs_header_level(eb)) + ret = btrfs_check_node(eb); + else + ret = btrfs_check_leaf_full(eb); + + if (ret < 0) { + btrfs_print_tree(eb, 0); + btrfs_err(fs_info, + "block=%llu write time tree block corruption detected", + eb->start); + WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG)); + return ret; + } + write_extent_buffer(eb, result, 0, csum_size); + + return 0; +} + +static int check_tree_block_fsid(struct extent_buffer *eb) +{ + struct btrfs_fs_info *fs_info = eb->fs_info; + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs; + u8 fsid[BTRFS_FSID_SIZE]; + u8 *metadata_uuid; + + read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid), + BTRFS_FSID_SIZE); + /* + * Checking the incompat flag is only valid for the current fs. For + * seed devices it's forbidden to have their uuid changed so reading + * ->fsid in this case is fine + */ + if (btrfs_fs_incompat(fs_info, METADATA_UUID)) + metadata_uuid = fs_devices->metadata_uuid; + else + metadata_uuid = fs_devices->fsid; + + if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE)) + return 0; + + list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) + if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE)) + return 0; + + return 1; +} + +int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio, u64 phy_offset, + struct page *page, u64 start, u64 end, + int mirror) +{ + u64 found_start; + int found_level; + struct extent_buffer *eb; + struct btrfs_fs_info *fs_info; + u16 csum_size; + int ret = 0; + u8 result[BTRFS_CSUM_SIZE]; + int reads_done; + + if (!page->private) + goto out; + + eb = (struct extent_buffer *)page->private; + fs_info = eb->fs_info; + csum_size = btrfs_super_csum_size(fs_info->super_copy); + + /* the pending IO might have been the only thing that kept this buffer + * in memory. Make sure we have a ref for all this other checks + */ + atomic_inc(&eb->refs); + + reads_done = atomic_dec_and_test(&eb->io_pages); + if (!reads_done) + goto err; + + eb->read_mirror = mirror; + if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) { + ret = -EIO; + goto err; + } + + found_start = btrfs_header_bytenr(eb); + if (found_start != eb->start) { + btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu", + eb->start, found_start); + ret = -EIO; + goto err; + } + if (check_tree_block_fsid(eb)) { + btrfs_err_rl(fs_info, "bad fsid on block %llu", + eb->start); + ret = -EIO; + goto err; + } + found_level = btrfs_header_level(eb); + if (found_level >= BTRFS_MAX_LEVEL) { + btrfs_err(fs_info, "bad tree block level %d on %llu", + (int)btrfs_header_level(eb), eb->start); + ret = -EIO; + goto err; + } + + btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb), + eb, found_level); + + csum_tree_block(eb, result); + + if (memcmp_extent_buffer(eb, result, 0, csum_size)) { + u8 val[BTRFS_CSUM_SIZE] = { 0 }; + + read_extent_buffer(eb, &val, 0, csum_size); + btrfs_warn_rl(fs_info, + "%s checksum verify failed on %llu wanted " CSUM_FMT " found " CSUM_FMT " level %d", + fs_info->sb->s_id, eb->start, + CSUM_FMT_VALUE(csum_size, val), + CSUM_FMT_VALUE(csum_size, result), + btrfs_header_level(eb)); + ret = -EUCLEAN; + goto err; + } + + /* + * If this is a leaf block and it is corrupt, set the corrupt bit so + * that we don't try and read the other copies of this block, just + * return -EIO. + */ + if (found_level == 0 && btrfs_check_leaf_full(eb)) { + set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags); + ret = -EIO; + } + + if (found_level > 0 && btrfs_check_node(eb)) + ret = -EIO; + + if (!ret) + set_extent_buffer_uptodate(eb); + else + btrfs_err(fs_info, + "block=%llu read time tree block corruption detected", + eb->start); +err: + if (reads_done && + test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) + btree_readahead_hook(eb, ret); + + if (ret) { + /* + * our io error hook is going to dec the io pages + * again, we have to make sure it has something + * to decrement + */ + atomic_inc(&eb->io_pages); + clear_extent_buffer_uptodate(eb); + } + free_extent_buffer(eb); +out: + return ret; +} + +static void end_workqueue_bio(struct bio *bio) +{ + struct btrfs_end_io_wq *end_io_wq = bio->bi_private; + struct btrfs_fs_info *fs_info; + struct btrfs_workqueue *wq; + + fs_info = end_io_wq->info; + end_io_wq->status = bio->bi_status; + + if (bio_op(bio) == REQ_OP_WRITE) { + if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA) + wq = fs_info->endio_meta_write_workers; + else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE) + wq = fs_info->endio_freespace_worker; + else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) + wq = fs_info->endio_raid56_workers; + else + wq = fs_info->endio_write_workers; + } else { + if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56) + wq = fs_info->endio_raid56_workers; + else if (end_io_wq->metadata) + wq = fs_info->endio_meta_workers; + else + wq = fs_info->endio_workers; + } + + btrfs_init_work(&end_io_wq->work, end_workqueue_fn, NULL, NULL); + btrfs_queue_work(wq, &end_io_wq->work); +} + +blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, + enum btrfs_wq_endio_type metadata) +{ + struct btrfs_end_io_wq *end_io_wq; + + end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS); + if (!end_io_wq) + return BLK_STS_RESOURCE; + + end_io_wq->private = bio->bi_private; + end_io_wq->end_io = bio->bi_end_io; + end_io_wq->info = info; + end_io_wq->status = 0; + end_io_wq->bio = bio; + end_io_wq->metadata = metadata; + + bio->bi_private = end_io_wq; + bio->bi_end_io = end_workqueue_bio; + return 0; +} + +static void run_one_async_start(struct btrfs_work *work) +{ + struct async_submit_bio *async; + blk_status_t ret; + + async = container_of(work, struct async_submit_bio, work); + ret = async->submit_bio_start(async->private_data, async->bio, + async->bio_offset); + if (ret) + async->status = ret; +} + +/* + * In order to insert checksums into the metadata in large chunks, we wait + * until bio submission time. All the pages in the bio are checksummed and + * sums are attached onto the ordered extent record. + * + * At IO completion time the csums attached on the ordered extent record are + * inserted into the tree. + */ +static void run_one_async_done(struct btrfs_work *work) +{ + struct async_submit_bio *async; + struct inode *inode; + blk_status_t ret; + + async = container_of(work, struct async_submit_bio, work); + inode = async->private_data; + + /* If an error occurred we just want to clean up the bio and move on */ + if (async->status) { + async->bio->bi_status = async->status; + bio_endio(async->bio); + return; + } + + /* + * All of the bios that pass through here are from async helpers. + * Use REQ_CGROUP_PUNT to issue them from the owning cgroup's context. + * This changes nothing when cgroups aren't in use. + */ + async->bio->bi_opf |= REQ_CGROUP_PUNT; + ret = btrfs_map_bio(btrfs_sb(inode->i_sb), async->bio, async->mirror_num); + if (ret) { + async->bio->bi_status = ret; + bio_endio(async->bio); + } +} + +static void run_one_async_free(struct btrfs_work *work) +{ + struct async_submit_bio *async; + + async = container_of(work, struct async_submit_bio, work); + kfree(async); +} + +blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, + int mirror_num, unsigned long bio_flags, + u64 bio_offset, void *private_data, + extent_submit_bio_start_t *submit_bio_start) +{ + struct async_submit_bio *async; + + async = kmalloc(sizeof(*async), GFP_NOFS); + if (!async) + return BLK_STS_RESOURCE; + + async->private_data = private_data; + async->bio = bio; + async->mirror_num = mirror_num; + async->submit_bio_start = submit_bio_start; + + btrfs_init_work(&async->work, run_one_async_start, run_one_async_done, + run_one_async_free); + + async->bio_offset = bio_offset; + + async->status = 0; + + if (op_is_sync(bio->bi_opf)) + btrfs_set_work_high_priority(&async->work); + + btrfs_queue_work(fs_info->workers, &async->work); + return 0; +} + +static blk_status_t btree_csum_one_bio(struct bio *bio) +{ + struct bio_vec *bvec; + struct btrfs_root *root; + int ret = 0; + struct bvec_iter_all iter_all; + + ASSERT(!bio_flagged(bio, BIO_CLONED)); + bio_for_each_segment_all(bvec, bio, iter_all) { + root = BTRFS_I(bvec->bv_page->mapping->host)->root; + ret = csum_dirty_buffer(root->fs_info, bvec->bv_page); + if (ret) + break; + } + + return errno_to_blk_status(ret); +} + +static blk_status_t btree_submit_bio_start(void *private_data, struct bio *bio, + u64 bio_offset) +{ + /* + * when we're called for a write, we're already in the async + * submission context. Just jump into btrfs_map_bio + */ + return btree_csum_one_bio(bio); +} + +static int check_async_write(struct btrfs_fs_info *fs_info, + struct btrfs_inode *bi) +{ + if (atomic_read(&bi->sync_writers)) + return 0; + if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags)) + return 0; + return 1; +} + +blk_status_t btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio, + int mirror_num, unsigned long bio_flags) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + int async = check_async_write(fs_info, BTRFS_I(inode)); + blk_status_t ret; + + if (bio_op(bio) != REQ_OP_WRITE) { + /* + * called for a read, do the setup so that checksum validation + * can happen in the async kernel threads + */ + ret = btrfs_bio_wq_end_io(fs_info, bio, + BTRFS_WQ_ENDIO_METADATA); + if (ret) + goto out_w_error; + ret = btrfs_map_bio(fs_info, bio, mirror_num); + } else if (!async) { + ret = btree_csum_one_bio(bio); + if (ret) + goto out_w_error; + ret = btrfs_map_bio(fs_info, bio, mirror_num); + } else { + /* + * kthread helpers are used to submit writes so that + * checksumming can happen in parallel across all CPUs + */ + ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, 0, + 0, inode, btree_submit_bio_start); + } + + if (ret) + goto out_w_error; + return 0; + +out_w_error: + bio->bi_status = ret; + bio_endio(bio); + return ret; +} + +#ifdef CONFIG_MIGRATION +static int btree_migratepage(struct address_space *mapping, + struct page *newpage, struct page *page, + enum migrate_mode mode) +{ + /* + * we can't safely write a btree page from here, + * we haven't done the locking hook + */ + if (PageDirty(page)) + return -EAGAIN; + /* + * Buffers may be managed in a filesystem specific way. + * We must have no buffers or drop them. + */ + if (page_has_private(page) && + !try_to_release_page(page, GFP_KERNEL)) + return -EAGAIN; + return migrate_page(mapping, newpage, page, mode); +} +#endif + + +static int btree_writepages(struct address_space *mapping, + struct writeback_control *wbc) +{ + struct btrfs_fs_info *fs_info; + int ret; + + if (wbc->sync_mode == WB_SYNC_NONE) { + + if (wbc->for_kupdate) + return 0; + + fs_info = BTRFS_I(mapping->host)->root->fs_info; + /* this is a bit racy, but that's ok */ + ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes, + BTRFS_DIRTY_METADATA_THRESH, + fs_info->dirty_metadata_batch); + if (ret < 0) + return 0; + } + return btree_write_cache_pages(mapping, wbc); +} + +static int btree_releasepage(struct page *page, gfp_t gfp_flags) +{ + if (PageWriteback(page) || PageDirty(page)) + return 0; + + return try_release_extent_buffer(page); +} + +static void btree_invalidatepage(struct page *page, unsigned int offset, + unsigned int length) +{ + struct extent_io_tree *tree; + tree = &BTRFS_I(page->mapping->host)->io_tree; + extent_invalidatepage(tree, page, offset); + btree_releasepage(page, GFP_NOFS); + if (PagePrivate(page)) { + btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info, + "page private not zero on page %llu", + (unsigned long long)page_offset(page)); + detach_page_private(page); + } +} + +static int btree_set_page_dirty(struct page *page) +{ +#ifdef DEBUG + struct extent_buffer *eb; + + BUG_ON(!PagePrivate(page)); + eb = (struct extent_buffer *)page->private; + BUG_ON(!eb); + BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); + BUG_ON(!atomic_read(&eb->refs)); + btrfs_assert_tree_locked(eb); +#endif + return __set_page_dirty_nobuffers(page); +} + +static const struct address_space_operations btree_aops = { + .writepages = btree_writepages, + .releasepage = btree_releasepage, + .invalidatepage = btree_invalidatepage, +#ifdef CONFIG_MIGRATION + .migratepage = btree_migratepage, +#endif + .set_page_dirty = btree_set_page_dirty, +}; + +void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr) +{ + struct extent_buffer *buf = NULL; + int ret; + + buf = btrfs_find_create_tree_block(fs_info, bytenr); + if (IS_ERR(buf)) + return; + + ret = read_extent_buffer_pages(buf, WAIT_NONE, 0); + if (ret < 0) + free_extent_buffer_stale(buf); + else + free_extent_buffer(buf); +} + +struct extent_buffer *btrfs_find_create_tree_block( + struct btrfs_fs_info *fs_info, + u64 bytenr) +{ + if (btrfs_is_testing(fs_info)) + return alloc_test_extent_buffer(fs_info, bytenr); + return alloc_extent_buffer(fs_info, bytenr); +} + +/* + * Read tree block at logical address @bytenr and do variant basic but critical + * verification. + * + * @parent_transid: expected transid of this tree block, skip check if 0 + * @level: expected level, mandatory check + * @first_key: expected key in slot 0, skip check if NULL + */ +struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr, + u64 parent_transid, int level, + struct btrfs_key *first_key) +{ + struct extent_buffer *buf = NULL; + int ret; + + buf = btrfs_find_create_tree_block(fs_info, bytenr); + if (IS_ERR(buf)) + return buf; + + ret = btree_read_extent_buffer_pages(buf, parent_transid, + level, first_key); + if (ret) { + free_extent_buffer_stale(buf); + return ERR_PTR(ret); + } + return buf; + +} + +void btrfs_clean_tree_block(struct extent_buffer *buf) +{ + struct btrfs_fs_info *fs_info = buf->fs_info; + if (btrfs_header_generation(buf) == + fs_info->running_transaction->transid) { + btrfs_assert_tree_locked(buf); + + if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) { + percpu_counter_add_batch(&fs_info->dirty_metadata_bytes, + -buf->len, + fs_info->dirty_metadata_batch); + /* ugh, clear_extent_buffer_dirty needs to lock the page */ + btrfs_set_lock_blocking_write(buf); + clear_extent_buffer_dirty(buf); + } + } +} + +static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info, + u64 objectid) +{ + bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state); + root->fs_info = fs_info; + root->node = NULL; + root->commit_root = NULL; + root->state = 0; + root->orphan_cleanup_state = 0; + + root->last_trans = 0; + root->highest_objectid = 0; + root->nr_delalloc_inodes = 0; + root->nr_ordered_extents = 0; + root->inode_tree = RB_ROOT; + INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC); + root->block_rsv = NULL; + + INIT_LIST_HEAD(&root->dirty_list); + INIT_LIST_HEAD(&root->root_list); + INIT_LIST_HEAD(&root->delalloc_inodes); + INIT_LIST_HEAD(&root->delalloc_root); + INIT_LIST_HEAD(&root->ordered_extents); + INIT_LIST_HEAD(&root->ordered_root); + INIT_LIST_HEAD(&root->reloc_dirty_list); + INIT_LIST_HEAD(&root->logged_list[0]); + INIT_LIST_HEAD(&root->logged_list[1]); + spin_lock_init(&root->inode_lock); + spin_lock_init(&root->delalloc_lock); + spin_lock_init(&root->ordered_extent_lock); + spin_lock_init(&root->accounting_lock); + spin_lock_init(&root->log_extents_lock[0]); + spin_lock_init(&root->log_extents_lock[1]); + spin_lock_init(&root->qgroup_meta_rsv_lock); + mutex_init(&root->objectid_mutex); + mutex_init(&root->log_mutex); + mutex_init(&root->ordered_extent_mutex); + mutex_init(&root->delalloc_mutex); + init_waitqueue_head(&root->qgroup_flush_wait); + init_waitqueue_head(&root->log_writer_wait); + init_waitqueue_head(&root->log_commit_wait[0]); + init_waitqueue_head(&root->log_commit_wait[1]); + INIT_LIST_HEAD(&root->log_ctxs[0]); + INIT_LIST_HEAD(&root->log_ctxs[1]); + atomic_set(&root->log_commit[0], 0); + atomic_set(&root->log_commit[1], 0); + atomic_set(&root->log_writers, 0); + atomic_set(&root->log_batch, 0); + refcount_set(&root->refs, 1); + atomic_set(&root->snapshot_force_cow, 0); + atomic_set(&root->nr_swapfiles, 0); + root->log_transid = 0; + root->log_transid_committed = -1; + root->last_log_commit = 0; + if (!dummy) { + extent_io_tree_init(fs_info, &root->dirty_log_pages, + IO_TREE_ROOT_DIRTY_LOG_PAGES, NULL); + extent_io_tree_init(fs_info, &root->log_csum_range, + IO_TREE_LOG_CSUM_RANGE, NULL); + } + + memset(&root->root_key, 0, sizeof(root->root_key)); + memset(&root->root_item, 0, sizeof(root->root_item)); + memset(&root->defrag_progress, 0, sizeof(root->defrag_progress)); + root->root_key.objectid = objectid; + root->anon_dev = 0; + + spin_lock_init(&root->root_item_lock); + btrfs_qgroup_init_swapped_blocks(&root->swapped_blocks); +#ifdef CONFIG_BTRFS_DEBUG + INIT_LIST_HEAD(&root->leak_list); + spin_lock(&fs_info->fs_roots_radix_lock); + list_add_tail(&root->leak_list, &fs_info->allocated_roots); + spin_unlock(&fs_info->fs_roots_radix_lock); +#endif +} + +static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info, + u64 objectid, gfp_t flags) +{ + struct btrfs_root *root = kzalloc(sizeof(*root), flags); + if (root) + __setup_root(root, fs_info, objectid); + return root; +} + +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS +/* Should only be used by the testing infrastructure */ +struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *root; + + if (!fs_info) + return ERR_PTR(-EINVAL); + + root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL); + if (!root) + return ERR_PTR(-ENOMEM); + + /* We don't use the stripesize in selftest, set it as sectorsize */ + root->alloc_bytenr = 0; + + return root; +} +#endif + +struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, + u64 objectid) +{ + struct btrfs_fs_info *fs_info = trans->fs_info; + struct extent_buffer *leaf; + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_root *root; + struct btrfs_key key; + unsigned int nofs_flag; + int ret = 0; + + /* + * We're holding a transaction handle, so use a NOFS memory allocation + * context to avoid deadlock if reclaim happens. + */ + nofs_flag = memalloc_nofs_save(); + root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL); + memalloc_nofs_restore(nofs_flag); + if (!root) + return ERR_PTR(-ENOMEM); + + root->root_key.objectid = objectid; + root->root_key.type = BTRFS_ROOT_ITEM_KEY; + root->root_key.offset = 0; + + leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0, + BTRFS_NESTING_NORMAL); + if (IS_ERR(leaf)) { + ret = PTR_ERR(leaf); + leaf = NULL; + goto fail; + } + + root->node = leaf; + btrfs_mark_buffer_dirty(leaf); + + root->commit_root = btrfs_root_node(root); + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + + root->root_item.flags = 0; + root->root_item.byte_limit = 0; + btrfs_set_root_bytenr(&root->root_item, leaf->start); + btrfs_set_root_generation(&root->root_item, trans->transid); + btrfs_set_root_level(&root->root_item, 0); + btrfs_set_root_refs(&root->root_item, 1); + btrfs_set_root_used(&root->root_item, leaf->len); + btrfs_set_root_last_snapshot(&root->root_item, 0); + btrfs_set_root_dirid(&root->root_item, 0); + if (is_fstree(objectid)) + generate_random_guid(root->root_item.uuid); + else + export_guid(root->root_item.uuid, &guid_null); + root->root_item.drop_level = 0; + + key.objectid = objectid; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = 0; + ret = btrfs_insert_root(trans, tree_root, &key, &root->root_item); + if (ret) + goto fail; + + btrfs_tree_unlock(leaf); + + return root; + +fail: + if (leaf) + btrfs_tree_unlock(leaf); + btrfs_put_root(root); + + return ERR_PTR(ret); +} + +static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *root; + struct extent_buffer *leaf; + + root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS); + if (!root) + return ERR_PTR(-ENOMEM); + + root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID; + root->root_key.type = BTRFS_ROOT_ITEM_KEY; + root->root_key.offset = BTRFS_TREE_LOG_OBJECTID; + + /* + * DON'T set SHAREABLE bit for log trees. + * + * Log trees are not exposed to user space thus can't be snapshotted, + * and they go away before a real commit is actually done. + * + * They do store pointers to file data extents, and those reference + * counts still get updated (along with back refs to the log tree). + */ + + leaf = btrfs_alloc_tree_block(trans, root, 0, BTRFS_TREE_LOG_OBJECTID, + NULL, 0, 0, 0, BTRFS_NESTING_NORMAL); + if (IS_ERR(leaf)) { + btrfs_put_root(root); + return ERR_CAST(leaf); + } + + root->node = leaf; + + btrfs_mark_buffer_dirty(root->node); + btrfs_tree_unlock(root->node); + return root; +} + +int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *log_root; + + log_root = alloc_log_tree(trans, fs_info); + if (IS_ERR(log_root)) + return PTR_ERR(log_root); + WARN_ON(fs_info->log_root_tree); + fs_info->log_root_tree = log_root; + return 0; +} + +int btrfs_add_log_tree(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_root *log_root; + struct btrfs_inode_item *inode_item; + + log_root = alloc_log_tree(trans, fs_info); + if (IS_ERR(log_root)) + return PTR_ERR(log_root); + + log_root->last_trans = trans->transid; + log_root->root_key.offset = root->root_key.objectid; + + inode_item = &log_root->root_item.inode; + btrfs_set_stack_inode_generation(inode_item, 1); + btrfs_set_stack_inode_size(inode_item, 3); + btrfs_set_stack_inode_nlink(inode_item, 1); + btrfs_set_stack_inode_nbytes(inode_item, + fs_info->nodesize); + btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); + + btrfs_set_root_node(&log_root->root_item, log_root->node); + + WARN_ON(root->log_root); + root->log_root = log_root; + root->log_transid = 0; + root->log_transid_committed = -1; + root->last_log_commit = 0; + return 0; +} + +static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root, + struct btrfs_path *path, + struct btrfs_key *key) +{ + struct btrfs_root *root; + struct btrfs_fs_info *fs_info = tree_root->fs_info; + u64 generation; + int ret; + int level; + + root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS); + if (!root) + return ERR_PTR(-ENOMEM); + + ret = btrfs_find_root(tree_root, key, path, + &root->root_item, &root->root_key); + if (ret) { + if (ret > 0) + ret = -ENOENT; + goto fail; + } + + generation = btrfs_root_generation(&root->root_item); + level = btrfs_root_level(&root->root_item); + root->node = read_tree_block(fs_info, + btrfs_root_bytenr(&root->root_item), + generation, level, NULL); + if (IS_ERR(root->node)) { + ret = PTR_ERR(root->node); + root->node = NULL; + goto fail; + } else if (!btrfs_buffer_uptodate(root->node, generation, 0)) { + ret = -EIO; + goto fail; + } + root->commit_root = btrfs_root_node(root); + return root; +fail: + btrfs_put_root(root); + return ERR_PTR(ret); +} + +struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root, + struct btrfs_key *key) +{ + struct btrfs_root *root; + struct btrfs_path *path; + + path = btrfs_alloc_path(); + if (!path) + return ERR_PTR(-ENOMEM); + root = read_tree_root_path(tree_root, path, key); + btrfs_free_path(path); + + return root; +} + +/* + * Initialize subvolume root in-memory structure + * + * @anon_dev: anonymous device to attach to the root, if zero, allocate new + */ +static int btrfs_init_fs_root(struct btrfs_root *root, dev_t anon_dev) +{ + int ret; + unsigned int nofs_flag; + + root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS); + root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned), + GFP_NOFS); + if (!root->free_ino_pinned || !root->free_ino_ctl) { + ret = -ENOMEM; + goto fail; + } + + /* + * We might be called under a transaction (e.g. indirect backref + * resolution) which could deadlock if it triggers memory reclaim + */ + nofs_flag = memalloc_nofs_save(); + ret = btrfs_drew_lock_init(&root->snapshot_lock); + memalloc_nofs_restore(nofs_flag); + if (ret) + goto fail; + + if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID && + root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) { + set_bit(BTRFS_ROOT_SHAREABLE, &root->state); + btrfs_check_and_init_root_item(&root->root_item); + } + + btrfs_init_free_ino_ctl(root); + spin_lock_init(&root->ino_cache_lock); + init_waitqueue_head(&root->ino_cache_wait); + + /* + * Don't assign anonymous block device to roots that are not exposed to + * userspace, the id pool is limited to 1M + */ + if (is_fstree(root->root_key.objectid) && + btrfs_root_refs(&root->root_item) > 0) { + if (!anon_dev) { + ret = get_anon_bdev(&root->anon_dev); + if (ret) + goto fail; + } else { + root->anon_dev = anon_dev; + } + } + + mutex_lock(&root->objectid_mutex); + ret = btrfs_find_highest_objectid(root, + &root->highest_objectid); + if (ret) { + mutex_unlock(&root->objectid_mutex); + goto fail; + } + + ASSERT(root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID); + + mutex_unlock(&root->objectid_mutex); + + return 0; +fail: + /* The caller is responsible to call btrfs_free_fs_root */ + return ret; +} + +static struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info, + u64 root_id) +{ + struct btrfs_root *root; + + spin_lock(&fs_info->fs_roots_radix_lock); + root = radix_tree_lookup(&fs_info->fs_roots_radix, + (unsigned long)root_id); + if (root) + root = btrfs_grab_root(root); + spin_unlock(&fs_info->fs_roots_radix_lock); + return root; +} + +static struct btrfs_root *btrfs_get_global_root(struct btrfs_fs_info *fs_info, + u64 objectid) +{ + if (objectid == BTRFS_ROOT_TREE_OBJECTID) + return btrfs_grab_root(fs_info->tree_root); + if (objectid == BTRFS_EXTENT_TREE_OBJECTID) + return btrfs_grab_root(fs_info->extent_root); + if (objectid == BTRFS_CHUNK_TREE_OBJECTID) + return btrfs_grab_root(fs_info->chunk_root); + if (objectid == BTRFS_DEV_TREE_OBJECTID) + return btrfs_grab_root(fs_info->dev_root); + if (objectid == BTRFS_CSUM_TREE_OBJECTID) + return btrfs_grab_root(fs_info->csum_root); + if (objectid == BTRFS_QUOTA_TREE_OBJECTID) + return btrfs_grab_root(fs_info->quota_root) ? + fs_info->quota_root : ERR_PTR(-ENOENT); + if (objectid == BTRFS_UUID_TREE_OBJECTID) + return btrfs_grab_root(fs_info->uuid_root) ? + fs_info->uuid_root : ERR_PTR(-ENOENT); + if (objectid == BTRFS_FREE_SPACE_TREE_OBJECTID) + return btrfs_grab_root(fs_info->free_space_root) ? + fs_info->free_space_root : ERR_PTR(-ENOENT); + return NULL; +} + +int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, + struct btrfs_root *root) +{ + int ret; + + ret = radix_tree_preload(GFP_NOFS); + if (ret) + return ret; + + spin_lock(&fs_info->fs_roots_radix_lock); + ret = radix_tree_insert(&fs_info->fs_roots_radix, + (unsigned long)root->root_key.objectid, + root); + if (ret == 0) { + btrfs_grab_root(root); + set_bit(BTRFS_ROOT_IN_RADIX, &root->state); + } + spin_unlock(&fs_info->fs_roots_radix_lock); + radix_tree_preload_end(); + + return ret; +} + +void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info) +{ +#ifdef CONFIG_BTRFS_DEBUG + struct btrfs_root *root; + + while (!list_empty(&fs_info->allocated_roots)) { + char buf[BTRFS_ROOT_NAME_BUF_LEN]; + + root = list_first_entry(&fs_info->allocated_roots, + struct btrfs_root, leak_list); + btrfs_err(fs_info, "leaked root %s refcount %d", + btrfs_root_name(&root->root_key, buf), + refcount_read(&root->refs)); + while (refcount_read(&root->refs) > 1) + btrfs_put_root(root); + btrfs_put_root(root); + } +#endif +} + +void btrfs_free_fs_info(struct btrfs_fs_info *fs_info) +{ + percpu_counter_destroy(&fs_info->dirty_metadata_bytes); + percpu_counter_destroy(&fs_info->delalloc_bytes); + percpu_counter_destroy(&fs_info->dio_bytes); + percpu_counter_destroy(&fs_info->dev_replace.bio_counter); + btrfs_free_csum_hash(fs_info); + btrfs_free_stripe_hash_table(fs_info); + btrfs_free_ref_cache(fs_info); + kfree(fs_info->balance_ctl); + kfree(fs_info->delayed_root); + btrfs_put_root(fs_info->extent_root); + btrfs_put_root(fs_info->tree_root); + btrfs_put_root(fs_info->chunk_root); + btrfs_put_root(fs_info->dev_root); + btrfs_put_root(fs_info->csum_root); + btrfs_put_root(fs_info->quota_root); + btrfs_put_root(fs_info->uuid_root); + btrfs_put_root(fs_info->free_space_root); + btrfs_put_root(fs_info->fs_root); + btrfs_put_root(fs_info->data_reloc_root); + btrfs_check_leaked_roots(fs_info); + btrfs_extent_buffer_leak_debug_check(fs_info); + kfree(fs_info->super_copy); + kfree(fs_info->super_for_commit); + kvfree(fs_info); +} + + +/* + * Get an in-memory reference of a root structure. + * + * For essential trees like root/extent tree, we grab it from fs_info directly. + * For subvolume trees, we check the cached filesystem roots first. If not + * found, then read it from disk and add it to cached fs roots. + * + * Caller should release the root by calling btrfs_put_root() after the usage. + * + * NOTE: Reloc and log trees can't be read by this function as they share the + * same root objectid. + * + * @objectid: root id + * @anon_dev: preallocated anonymous block device number for new roots, + * pass 0 for new allocation. + * @check_ref: whether to check root item references, If true, return -ENOENT + * for orphan roots + */ +static struct btrfs_root *btrfs_get_root_ref(struct btrfs_fs_info *fs_info, + u64 objectid, dev_t anon_dev, + bool check_ref) +{ + struct btrfs_root *root; + struct btrfs_path *path; + struct btrfs_key key; + int ret; + + root = btrfs_get_global_root(fs_info, objectid); + if (root) + return root; +again: + root = btrfs_lookup_fs_root(fs_info, objectid); + if (root) { + /* Shouldn't get preallocated anon_dev for cached roots */ + ASSERT(!anon_dev); + if (check_ref && btrfs_root_refs(&root->root_item) == 0) { + btrfs_put_root(root); + return ERR_PTR(-ENOENT); + } + return root; + } + + key.objectid = objectid; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = btrfs_read_tree_root(fs_info->tree_root, &key); + if (IS_ERR(root)) + return root; + + if (check_ref && btrfs_root_refs(&root->root_item) == 0) { + ret = -ENOENT; + goto fail; + } + + ret = btrfs_init_fs_root(root, anon_dev); + if (ret) + goto fail; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto fail; + } + key.objectid = BTRFS_ORPHAN_OBJECTID; + key.type = BTRFS_ORPHAN_ITEM_KEY; + key.offset = objectid; + + ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); + btrfs_free_path(path); + if (ret < 0) + goto fail; + if (ret == 0) + set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state); + + ret = btrfs_insert_fs_root(fs_info, root); + if (ret) { + if (ret == -EEXIST) { + btrfs_put_root(root); + goto again; + } + goto fail; + } + return root; +fail: + /* + * If our caller provided us an anonymous device, then it's his + * responsability to free it in case we fail. So we have to set our + * root's anon_dev to 0 to avoid a double free, once by btrfs_put_root() + * and once again by our caller. + */ + if (anon_dev) + root->anon_dev = 0; + btrfs_put_root(root); + return ERR_PTR(ret); +} + +/* + * Get in-memory reference of a root structure + * + * @objectid: tree objectid + * @check_ref: if set, verify that the tree exists and the item has at least + * one reference + */ +struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, + u64 objectid, bool check_ref) +{ + return btrfs_get_root_ref(fs_info, objectid, 0, check_ref); +} + +/* + * Get in-memory reference of a root structure, created as new, optionally pass + * the anonymous block device id + * + * @objectid: tree objectid + * @anon_dev: if zero, allocate a new anonymous block device or use the + * parameter value + */ +struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info, + u64 objectid, dev_t anon_dev) +{ + return btrfs_get_root_ref(fs_info, objectid, anon_dev, true); +} + +/* + * btrfs_get_fs_root_commit_root - return a root for the given objectid + * @fs_info: the fs_info + * @objectid: the objectid we need to lookup + * + * This is exclusively used for backref walking, and exists specifically because + * of how qgroups does lookups. Qgroups will do a backref lookup at delayed ref + * creation time, which means we may have to read the tree_root in order to look + * up a fs root that is not in memory. If the root is not in memory we will + * read the tree root commit root and look up the fs root from there. This is a + * temporary root, it will not be inserted into the radix tree as it doesn't + * have the most uptodate information, it'll simply be discarded once the + * backref code is finished using the root. + */ +struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info, + struct btrfs_path *path, + u64 objectid) +{ + struct btrfs_root *root; + struct btrfs_key key; + + ASSERT(path->search_commit_root && path->skip_locking); + + /* + * This can return -ENOENT if we ask for a root that doesn't exist, but + * since this is called via the backref walking code we won't be looking + * up a root that doesn't exist, unless there's corruption. So if root + * != NULL just return it. + */ + root = btrfs_get_global_root(fs_info, objectid); + if (root) + return root; + + root = btrfs_lookup_fs_root(fs_info, objectid); + if (root) + return root; + + key.objectid = objectid; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = read_tree_root_path(fs_info->tree_root, path, &key); + btrfs_release_path(path); + + return root; +} + +/* + * called by the kthread helper functions to finally call the bio end_io + * functions. This is where read checksum verification actually happens + */ +static void end_workqueue_fn(struct btrfs_work *work) +{ + struct bio *bio; + struct btrfs_end_io_wq *end_io_wq; + + end_io_wq = container_of(work, struct btrfs_end_io_wq, work); + bio = end_io_wq->bio; + + bio->bi_status = end_io_wq->status; + bio->bi_private = end_io_wq->private; + bio->bi_end_io = end_io_wq->end_io; + bio_endio(bio); + kmem_cache_free(btrfs_end_io_wq_cache, end_io_wq); +} + +static int cleaner_kthread(void *arg) +{ + struct btrfs_root *root = arg; + struct btrfs_fs_info *fs_info = root->fs_info; + int again; + + while (1) { + again = 0; + + set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags); + + /* Make the cleaner go to sleep early. */ + if (btrfs_need_cleaner_sleep(fs_info)) + goto sleep; + + /* + * Do not do anything if we might cause open_ctree() to block + * before we have finished mounting the filesystem. + */ + if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags)) + goto sleep; + + if (!mutex_trylock(&fs_info->cleaner_mutex)) + goto sleep; + + /* + * Avoid the problem that we change the status of the fs + * during the above check and trylock. + */ + if (btrfs_need_cleaner_sleep(fs_info)) { + mutex_unlock(&fs_info->cleaner_mutex); + goto sleep; + } + + btrfs_run_delayed_iputs(fs_info); + + again = btrfs_clean_one_deleted_snapshot(root); + mutex_unlock(&fs_info->cleaner_mutex); + + /* + * The defragger has dealt with the R/O remount and umount, + * needn't do anything special here. + */ + btrfs_run_defrag_inodes(fs_info); + + /* + * Acquires fs_info->delete_unused_bgs_mutex to avoid racing + * with relocation (btrfs_relocate_chunk) and relocation + * acquires fs_info->cleaner_mutex (btrfs_relocate_block_group) + * after acquiring fs_info->delete_unused_bgs_mutex. So we + * can't hold, nor need to, fs_info->cleaner_mutex when deleting + * unused block groups. + */ + btrfs_delete_unused_bgs(fs_info); +sleep: + clear_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags); + if (kthread_should_park()) + kthread_parkme(); + if (kthread_should_stop()) + return 0; + if (!again) { + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + __set_current_state(TASK_RUNNING); + } + } +} + +static int transaction_kthread(void *arg) +{ + struct btrfs_root *root = arg; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_trans_handle *trans; + struct btrfs_transaction *cur; + u64 transid; + time64_t now; + unsigned long delay; + bool cannot_commit; + + do { + cannot_commit = false; + delay = HZ * fs_info->commit_interval; + mutex_lock(&fs_info->transaction_kthread_mutex); + + spin_lock(&fs_info->trans_lock); + cur = fs_info->running_transaction; + if (!cur) { + spin_unlock(&fs_info->trans_lock); + goto sleep; + } + + now = ktime_get_seconds(); + if (cur->state < TRANS_STATE_COMMIT_START && + (now < cur->start_time || + now - cur->start_time < fs_info->commit_interval)) { + spin_unlock(&fs_info->trans_lock); + delay = HZ * 5; + goto sleep; + } + transid = cur->transid; + spin_unlock(&fs_info->trans_lock); + + /* If the file system is aborted, this will always fail. */ + trans = btrfs_attach_transaction(root); + if (IS_ERR(trans)) { + if (PTR_ERR(trans) != -ENOENT) + cannot_commit = true; + goto sleep; + } + if (transid == trans->transid) { + btrfs_commit_transaction(trans); + } else { + btrfs_end_transaction(trans); + } +sleep: + wake_up_process(fs_info->cleaner_kthread); + mutex_unlock(&fs_info->transaction_kthread_mutex); + + if (unlikely(test_bit(BTRFS_FS_STATE_ERROR, + &fs_info->fs_state))) + btrfs_cleanup_transaction(fs_info); + if (!kthread_should_stop() && + (!btrfs_transaction_blocked(fs_info) || + cannot_commit)) + schedule_timeout_interruptible(delay); + } while (!kthread_should_stop()); + return 0; +} + +/* + * This will find the highest generation in the array of root backups. The + * index of the highest array is returned, or -EINVAL if we can't find + * anything. + * + * We check to make sure the array is valid by comparing the + * generation of the latest root in the array with the generation + * in the super block. If they don't match we pitch it. + */ +static int find_newest_super_backup(struct btrfs_fs_info *info) +{ + const u64 newest_gen = btrfs_super_generation(info->super_copy); + u64 cur; + struct btrfs_root_backup *root_backup; + int i; + + for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) { + root_backup = info->super_copy->super_roots + i; + cur = btrfs_backup_tree_root_gen(root_backup); + if (cur == newest_gen) + return i; + } + + return -EINVAL; +} + +/* + * copy all the root pointers into the super backup array. + * this will bump the backup pointer by one when it is + * done + */ +static void backup_super_roots(struct btrfs_fs_info *info) +{ + const int next_backup = info->backup_root_index; + struct btrfs_root_backup *root_backup; + + root_backup = info->super_for_commit->super_roots + next_backup; + + /* + * make sure all of our padding and empty slots get zero filled + * regardless of which ones we use today + */ + memset(root_backup, 0, sizeof(*root_backup)); + + info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS; + + btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start); + btrfs_set_backup_tree_root_gen(root_backup, + btrfs_header_generation(info->tree_root->node)); + + btrfs_set_backup_tree_root_level(root_backup, + btrfs_header_level(info->tree_root->node)); + + btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start); + btrfs_set_backup_chunk_root_gen(root_backup, + btrfs_header_generation(info->chunk_root->node)); + btrfs_set_backup_chunk_root_level(root_backup, + btrfs_header_level(info->chunk_root->node)); + + btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start); + btrfs_set_backup_extent_root_gen(root_backup, + btrfs_header_generation(info->extent_root->node)); + btrfs_set_backup_extent_root_level(root_backup, + btrfs_header_level(info->extent_root->node)); + + /* + * we might commit during log recovery, which happens before we set + * the fs_root. Make sure it is valid before we fill it in. + */ + if (info->fs_root && info->fs_root->node) { + btrfs_set_backup_fs_root(root_backup, + info->fs_root->node->start); + btrfs_set_backup_fs_root_gen(root_backup, + btrfs_header_generation(info->fs_root->node)); + btrfs_set_backup_fs_root_level(root_backup, + btrfs_header_level(info->fs_root->node)); + } + + btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start); + btrfs_set_backup_dev_root_gen(root_backup, + btrfs_header_generation(info->dev_root->node)); + btrfs_set_backup_dev_root_level(root_backup, + btrfs_header_level(info->dev_root->node)); + + btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start); + btrfs_set_backup_csum_root_gen(root_backup, + btrfs_header_generation(info->csum_root->node)); + btrfs_set_backup_csum_root_level(root_backup, + btrfs_header_level(info->csum_root->node)); + + btrfs_set_backup_total_bytes(root_backup, + btrfs_super_total_bytes(info->super_copy)); + btrfs_set_backup_bytes_used(root_backup, + btrfs_super_bytes_used(info->super_copy)); + btrfs_set_backup_num_devices(root_backup, + btrfs_super_num_devices(info->super_copy)); + + /* + * if we don't copy this out to the super_copy, it won't get remembered + * for the next commit + */ + memcpy(&info->super_copy->super_roots, + &info->super_for_commit->super_roots, + sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS); +} + +/* + * read_backup_root - Reads a backup root based on the passed priority. Prio 0 + * is the newest, prio 1/2/3 are 2nd newest/3rd newest/4th (oldest) backup roots + * + * fs_info - filesystem whose backup roots need to be read + * priority - priority of backup root required + * + * Returns backup root index on success and -EINVAL otherwise. + */ +static int read_backup_root(struct btrfs_fs_info *fs_info, u8 priority) +{ + int backup_index = find_newest_super_backup(fs_info); + struct btrfs_super_block *super = fs_info->super_copy; + struct btrfs_root_backup *root_backup; + + if (priority < BTRFS_NUM_BACKUP_ROOTS && backup_index >= 0) { + if (priority == 0) + return backup_index; + + backup_index = backup_index + BTRFS_NUM_BACKUP_ROOTS - priority; + backup_index %= BTRFS_NUM_BACKUP_ROOTS; + } else { + return -EINVAL; + } + + root_backup = super->super_roots + backup_index; + + btrfs_set_super_generation(super, + btrfs_backup_tree_root_gen(root_backup)); + btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup)); + btrfs_set_super_root_level(super, + btrfs_backup_tree_root_level(root_backup)); + btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup)); + + /* + * Fixme: the total bytes and num_devices need to match or we should + * need a fsck + */ + btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup)); + btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup)); + + return backup_index; +} + +/* helper to cleanup workers */ +static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info) +{ + btrfs_destroy_workqueue(fs_info->fixup_workers); + btrfs_destroy_workqueue(fs_info->delalloc_workers); + btrfs_destroy_workqueue(fs_info->workers); + btrfs_destroy_workqueue(fs_info->endio_workers); + btrfs_destroy_workqueue(fs_info->endio_raid56_workers); + btrfs_destroy_workqueue(fs_info->rmw_workers); + btrfs_destroy_workqueue(fs_info->endio_write_workers); + btrfs_destroy_workqueue(fs_info->endio_freespace_worker); + btrfs_destroy_workqueue(fs_info->delayed_workers); + btrfs_destroy_workqueue(fs_info->caching_workers); + btrfs_destroy_workqueue(fs_info->readahead_workers); + btrfs_destroy_workqueue(fs_info->flush_workers); + btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers); + if (fs_info->discard_ctl.discard_workers) + destroy_workqueue(fs_info->discard_ctl.discard_workers); + /* + * Now that all other work queues are destroyed, we can safely destroy + * the queues used for metadata I/O, since tasks from those other work + * queues can do metadata I/O operations. + */ + btrfs_destroy_workqueue(fs_info->endio_meta_workers); + btrfs_destroy_workqueue(fs_info->endio_meta_write_workers); +} + +static void free_root_extent_buffers(struct btrfs_root *root) +{ + if (root) { + free_extent_buffer(root->node); + free_extent_buffer(root->commit_root); + root->node = NULL; + root->commit_root = NULL; + } +} + +/* helper to cleanup tree roots */ +static void free_root_pointers(struct btrfs_fs_info *info, bool free_chunk_root) +{ + free_root_extent_buffers(info->tree_root); + + free_root_extent_buffers(info->dev_root); + free_root_extent_buffers(info->extent_root); + free_root_extent_buffers(info->csum_root); + free_root_extent_buffers(info->quota_root); + free_root_extent_buffers(info->uuid_root); + free_root_extent_buffers(info->fs_root); + free_root_extent_buffers(info->data_reloc_root); + if (free_chunk_root) + free_root_extent_buffers(info->chunk_root); + free_root_extent_buffers(info->free_space_root); +} + +void btrfs_put_root(struct btrfs_root *root) +{ + if (!root) + return; + + if (refcount_dec_and_test(&root->refs)) { + WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree)); + WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state)); + if (root->anon_dev) + free_anon_bdev(root->anon_dev); + btrfs_drew_lock_destroy(&root->snapshot_lock); + free_root_extent_buffers(root); + kfree(root->free_ino_ctl); + kfree(root->free_ino_pinned); +#ifdef CONFIG_BTRFS_DEBUG + spin_lock(&root->fs_info->fs_roots_radix_lock); + list_del_init(&root->leak_list); + spin_unlock(&root->fs_info->fs_roots_radix_lock); +#endif + kfree(root); + } +} + +void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info) +{ + int ret; + struct btrfs_root *gang[8]; + int i; + + while (!list_empty(&fs_info->dead_roots)) { + gang[0] = list_entry(fs_info->dead_roots.next, + struct btrfs_root, root_list); + list_del(&gang[0]->root_list); + + if (test_bit(BTRFS_ROOT_IN_RADIX, &gang[0]->state)) + btrfs_drop_and_free_fs_root(fs_info, gang[0]); + btrfs_put_root(gang[0]); + } + + while (1) { + ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, + (void **)gang, 0, + ARRAY_SIZE(gang)); + if (!ret) + break; + for (i = 0; i < ret; i++) + btrfs_drop_and_free_fs_root(fs_info, gang[i]); + } +} + +static void btrfs_init_scrub(struct btrfs_fs_info *fs_info) +{ + mutex_init(&fs_info->scrub_lock); + atomic_set(&fs_info->scrubs_running, 0); + atomic_set(&fs_info->scrub_pause_req, 0); + atomic_set(&fs_info->scrubs_paused, 0); + atomic_set(&fs_info->scrub_cancel_req, 0); + init_waitqueue_head(&fs_info->scrub_pause_wait); + refcount_set(&fs_info->scrub_workers_refcnt, 0); +} + +static void btrfs_init_balance(struct btrfs_fs_info *fs_info) +{ + spin_lock_init(&fs_info->balance_lock); + mutex_init(&fs_info->balance_mutex); + atomic_set(&fs_info->balance_pause_req, 0); + atomic_set(&fs_info->balance_cancel_req, 0); + fs_info->balance_ctl = NULL; + init_waitqueue_head(&fs_info->balance_wait_q); +} + +static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info) +{ + struct inode *inode = fs_info->btree_inode; + + inode->i_ino = BTRFS_BTREE_INODE_OBJECTID; + set_nlink(inode, 1); + /* + * we set the i_size on the btree inode to the max possible int. + * the real end of the address space is determined by all of + * the devices in the system + */ + inode->i_size = OFFSET_MAX; + inode->i_mapping->a_ops = &btree_aops; + + RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); + extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree, + IO_TREE_BTREE_INODE_IO, inode); + BTRFS_I(inode)->io_tree.track_uptodate = false; + extent_map_tree_init(&BTRFS_I(inode)->extent_tree); + + BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root); + memset(&BTRFS_I(inode)->location, 0, sizeof(struct btrfs_key)); + set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags); + btrfs_insert_inode_hash(inode); +} + +static void btrfs_init_dev_replace_locks(struct btrfs_fs_info *fs_info) +{ + mutex_init(&fs_info->dev_replace.lock_finishing_cancel_unmount); + init_rwsem(&fs_info->dev_replace.rwsem); + init_waitqueue_head(&fs_info->dev_replace.replace_wait); +} + +static void btrfs_init_qgroup(struct btrfs_fs_info *fs_info) +{ + spin_lock_init(&fs_info->qgroup_lock); + mutex_init(&fs_info->qgroup_ioctl_lock); + fs_info->qgroup_tree = RB_ROOT; + INIT_LIST_HEAD(&fs_info->dirty_qgroups); + fs_info->qgroup_seq = 1; + fs_info->qgroup_ulist = NULL; + fs_info->qgroup_rescan_running = false; + mutex_init(&fs_info->qgroup_rescan_lock); +} + +static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info, + struct btrfs_fs_devices *fs_devices) +{ + u32 max_active = fs_info->thread_pool_size; + unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND; + + fs_info->workers = + btrfs_alloc_workqueue(fs_info, "worker", + flags | WQ_HIGHPRI, max_active, 16); + + fs_info->delalloc_workers = + btrfs_alloc_workqueue(fs_info, "delalloc", + flags, max_active, 2); + + fs_info->flush_workers = + btrfs_alloc_workqueue(fs_info, "flush_delalloc", + flags, max_active, 0); + + fs_info->caching_workers = + btrfs_alloc_workqueue(fs_info, "cache", flags, max_active, 0); + + fs_info->fixup_workers = + btrfs_alloc_workqueue(fs_info, "fixup", flags, 1, 0); + + /* + * endios are largely parallel and should have a very + * low idle thresh + */ + fs_info->endio_workers = + btrfs_alloc_workqueue(fs_info, "endio", flags, max_active, 4); + fs_info->endio_meta_workers = + btrfs_alloc_workqueue(fs_info, "endio-meta", flags, + max_active, 4); + fs_info->endio_meta_write_workers = + btrfs_alloc_workqueue(fs_info, "endio-meta-write", flags, + max_active, 2); + fs_info->endio_raid56_workers = + btrfs_alloc_workqueue(fs_info, "endio-raid56", flags, + max_active, 4); + fs_info->rmw_workers = + btrfs_alloc_workqueue(fs_info, "rmw", flags, max_active, 2); + fs_info->endio_write_workers = + btrfs_alloc_workqueue(fs_info, "endio-write", flags, + max_active, 2); + fs_info->endio_freespace_worker = + btrfs_alloc_workqueue(fs_info, "freespace-write", flags, + max_active, 0); + fs_info->delayed_workers = + btrfs_alloc_workqueue(fs_info, "delayed-meta", flags, + max_active, 0); + fs_info->readahead_workers = + btrfs_alloc_workqueue(fs_info, "readahead", flags, + max_active, 2); + fs_info->qgroup_rescan_workers = + btrfs_alloc_workqueue(fs_info, "qgroup-rescan", flags, 1, 0); + fs_info->discard_ctl.discard_workers = + alloc_workqueue("btrfs_discard", WQ_UNBOUND | WQ_FREEZABLE, 1); + + if (!(fs_info->workers && fs_info->delalloc_workers && + fs_info->flush_workers && + fs_info->endio_workers && fs_info->endio_meta_workers && + fs_info->endio_meta_write_workers && + fs_info->endio_write_workers && fs_info->endio_raid56_workers && + fs_info->endio_freespace_worker && fs_info->rmw_workers && + fs_info->caching_workers && fs_info->readahead_workers && + fs_info->fixup_workers && fs_info->delayed_workers && + fs_info->qgroup_rescan_workers && + fs_info->discard_ctl.discard_workers)) { + return -ENOMEM; + } + + return 0; +} + +static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info, u16 csum_type) +{ + struct crypto_shash *csum_shash; + const char *csum_driver = btrfs_super_csum_driver(csum_type); + + csum_shash = crypto_alloc_shash(csum_driver, 0, 0); + + if (IS_ERR(csum_shash)) { + btrfs_err(fs_info, "error allocating %s hash for checksum", + csum_driver); + return PTR_ERR(csum_shash); + } + + fs_info->csum_shash = csum_shash; + + /* + * Check if the checksum implementation is a fast accelerated one. + * As-is this is a bit of a hack and should be replaced once the csum + * implementations provide that information themselves. + */ + switch (csum_type) { + case BTRFS_CSUM_TYPE_CRC32: + if (!strstr(crypto_shash_driver_name(csum_shash), "generic")) + set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags); + break; + case BTRFS_CSUM_TYPE_XXHASH: + set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags); + break; + default: + break; + } + + btrfs_info(fs_info, "using %s (%s) checksum algorithm", + btrfs_super_csum_name(csum_type), + crypto_shash_driver_name(csum_shash)); + return 0; +} + +static int btrfs_replay_log(struct btrfs_fs_info *fs_info, + struct btrfs_fs_devices *fs_devices) +{ + int ret; + struct btrfs_root *log_tree_root; + struct btrfs_super_block *disk_super = fs_info->super_copy; + u64 bytenr = btrfs_super_log_root(disk_super); + int level = btrfs_super_log_root_level(disk_super); + + if (fs_devices->rw_devices == 0) { + btrfs_warn(fs_info, "log replay required on RO media"); + return -EIO; + } + + log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, + GFP_KERNEL); + if (!log_tree_root) + return -ENOMEM; + + log_tree_root->node = read_tree_block(fs_info, bytenr, + fs_info->generation + 1, + level, NULL); + if (IS_ERR(log_tree_root->node)) { + btrfs_warn(fs_info, "failed to read log tree"); + ret = PTR_ERR(log_tree_root->node); + log_tree_root->node = NULL; + btrfs_put_root(log_tree_root); + return ret; + } else if (!extent_buffer_uptodate(log_tree_root->node)) { + btrfs_err(fs_info, "failed to read log tree"); + btrfs_put_root(log_tree_root); + return -EIO; + } + /* returns with log_tree_root freed on success */ + ret = btrfs_recover_log_trees(log_tree_root); + if (ret) { + btrfs_handle_fs_error(fs_info, ret, + "Failed to recover log tree"); + btrfs_put_root(log_tree_root); + return ret; + } + + if (sb_rdonly(fs_info->sb)) { + ret = btrfs_commit_super(fs_info); + if (ret) + return ret; + } + + return 0; +} + +static int btrfs_read_roots(struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_root *root; + struct btrfs_key location; + int ret; + + BUG_ON(!fs_info->tree_root); + + location.objectid = BTRFS_EXTENT_TREE_OBJECTID; + location.type = BTRFS_ROOT_ITEM_KEY; + location.offset = 0; + + root = btrfs_read_tree_root(tree_root, &location); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->extent_root = root; + + location.objectid = BTRFS_DEV_TREE_OBJECTID; + root = btrfs_read_tree_root(tree_root, &location); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->dev_root = root; + btrfs_init_devices_late(fs_info); + + location.objectid = BTRFS_CSUM_TREE_OBJECTID; + root = btrfs_read_tree_root(tree_root, &location); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->csum_root = root; + + /* + * This tree can share blocks with some other fs tree during relocation + * and we need a proper setup by btrfs_get_fs_root + */ + root = btrfs_get_fs_root(tree_root->fs_info, + BTRFS_DATA_RELOC_TREE_OBJECTID, true); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->data_reloc_root = root; + + location.objectid = BTRFS_QUOTA_TREE_OBJECTID; + root = btrfs_read_tree_root(tree_root, &location); + if (!IS_ERR(root)) { + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags); + fs_info->quota_root = root; + } + + location.objectid = BTRFS_UUID_TREE_OBJECTID; + root = btrfs_read_tree_root(tree_root, &location); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + if (ret != -ENOENT) + goto out; + } else { + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->uuid_root = root; + } + + if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID; + root = btrfs_read_tree_root(tree_root, &location); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->free_space_root = root; + } + + return 0; +out: + btrfs_warn(fs_info, "failed to read root (objectid=%llu): %d", + location.objectid, ret); + return ret; +} + +/* + * Real super block validation + * NOTE: super csum type and incompat features will not be checked here. + * + * @sb: super block to check + * @mirror_num: the super block number to check its bytenr: + * 0 the primary (1st) sb + * 1, 2 2nd and 3rd backup copy + * -1 skip bytenr check + */ +static int validate_super(struct btrfs_fs_info *fs_info, + struct btrfs_super_block *sb, int mirror_num) +{ + u64 nodesize = btrfs_super_nodesize(sb); + u64 sectorsize = btrfs_super_sectorsize(sb); + int ret = 0; + + if (btrfs_super_magic(sb) != BTRFS_MAGIC) { + btrfs_err(fs_info, "no valid FS found"); + ret = -EINVAL; + } + if (btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP) { + btrfs_err(fs_info, "unrecognized or unsupported super flag: %llu", + btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP); + ret = -EINVAL; + } + if (btrfs_super_root_level(sb) >= BTRFS_MAX_LEVEL) { + btrfs_err(fs_info, "tree_root level too big: %d >= %d", + btrfs_super_root_level(sb), BTRFS_MAX_LEVEL); + ret = -EINVAL; + } + if (btrfs_super_chunk_root_level(sb) >= BTRFS_MAX_LEVEL) { + btrfs_err(fs_info, "chunk_root level too big: %d >= %d", + btrfs_super_chunk_root_level(sb), BTRFS_MAX_LEVEL); + ret = -EINVAL; + } + if (btrfs_super_log_root_level(sb) >= BTRFS_MAX_LEVEL) { + btrfs_err(fs_info, "log_root level too big: %d >= %d", + btrfs_super_log_root_level(sb), BTRFS_MAX_LEVEL); + ret = -EINVAL; + } + + /* + * Check sectorsize and nodesize first, other check will need it. + * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here. + */ + if (!is_power_of_2(sectorsize) || sectorsize < 4096 || + sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) { + btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize); + ret = -EINVAL; + } + /* Only PAGE SIZE is supported yet */ + if (sectorsize != PAGE_SIZE) { + btrfs_err(fs_info, + "sectorsize %llu not supported yet, only support %lu", + sectorsize, PAGE_SIZE); + ret = -EINVAL; + } + if (!is_power_of_2(nodesize) || nodesize < sectorsize || + nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) { + btrfs_err(fs_info, "invalid nodesize %llu", nodesize); + ret = -EINVAL; + } + if (nodesize != le32_to_cpu(sb->__unused_leafsize)) { + btrfs_err(fs_info, "invalid leafsize %u, should be %llu", + le32_to_cpu(sb->__unused_leafsize), nodesize); + ret = -EINVAL; + } + + /* Root alignment check */ + if (!IS_ALIGNED(btrfs_super_root(sb), sectorsize)) { + btrfs_warn(fs_info, "tree_root block unaligned: %llu", + btrfs_super_root(sb)); + ret = -EINVAL; + } + if (!IS_ALIGNED(btrfs_super_chunk_root(sb), sectorsize)) { + btrfs_warn(fs_info, "chunk_root block unaligned: %llu", + btrfs_super_chunk_root(sb)); + ret = -EINVAL; + } + if (!IS_ALIGNED(btrfs_super_log_root(sb), sectorsize)) { + btrfs_warn(fs_info, "log_root block unaligned: %llu", + btrfs_super_log_root(sb)); + ret = -EINVAL; + } + + if (memcmp(fs_info->fs_devices->fsid, sb->fsid, BTRFS_FSID_SIZE) != 0) { + btrfs_err(fs_info, + "superblock fsid doesn't match fsid of fs_devices: %pU != %pU", + sb->fsid, fs_info->fs_devices->fsid); + ret = -EINVAL; + } + + if (memcmp(fs_info->fs_devices->metadata_uuid, btrfs_sb_fsid_ptr(sb), + BTRFS_FSID_SIZE) != 0) { + btrfs_err(fs_info, +"superblock metadata_uuid doesn't match metadata uuid of fs_devices: %pU != %pU", + btrfs_sb_fsid_ptr(sb), fs_info->fs_devices->metadata_uuid); + ret = -EINVAL; + } + + if (memcmp(fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid, + BTRFS_FSID_SIZE) != 0) { + btrfs_err(fs_info, + "dev_item UUID does not match metadata fsid: %pU != %pU", + fs_info->fs_devices->metadata_uuid, sb->dev_item.fsid); + ret = -EINVAL; + } + + /* + * Hint to catch really bogus numbers, bitflips or so, more exact checks are + * done later + */ + if (btrfs_super_bytes_used(sb) < 6 * btrfs_super_nodesize(sb)) { + btrfs_err(fs_info, "bytes_used is too small %llu", + btrfs_super_bytes_used(sb)); + ret = -EINVAL; + } + if (!is_power_of_2(btrfs_super_stripesize(sb))) { + btrfs_err(fs_info, "invalid stripesize %u", + btrfs_super_stripesize(sb)); + ret = -EINVAL; + } + if (btrfs_super_num_devices(sb) > (1UL << 31)) + btrfs_warn(fs_info, "suspicious number of devices: %llu", + btrfs_super_num_devices(sb)); + if (btrfs_super_num_devices(sb) == 0) { + btrfs_err(fs_info, "number of devices is 0"); + ret = -EINVAL; + } + + if (mirror_num >= 0 && + btrfs_super_bytenr(sb) != btrfs_sb_offset(mirror_num)) { + btrfs_err(fs_info, "super offset mismatch %llu != %u", + btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET); + ret = -EINVAL; + } + + /* + * Obvious sys_chunk_array corruptions, it must hold at least one key + * and one chunk + */ + if (btrfs_super_sys_array_size(sb) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) { + btrfs_err(fs_info, "system chunk array too big %u > %u", + btrfs_super_sys_array_size(sb), + BTRFS_SYSTEM_CHUNK_ARRAY_SIZE); + ret = -EINVAL; + } + if (btrfs_super_sys_array_size(sb) < sizeof(struct btrfs_disk_key) + + sizeof(struct btrfs_chunk)) { + btrfs_err(fs_info, "system chunk array too small %u < %zu", + btrfs_super_sys_array_size(sb), + sizeof(struct btrfs_disk_key) + + sizeof(struct btrfs_chunk)); + ret = -EINVAL; + } + + /* + * The generation is a global counter, we'll trust it more than the others + * but it's still possible that it's the one that's wrong. + */ + if (btrfs_super_generation(sb) < btrfs_super_chunk_root_generation(sb)) + btrfs_warn(fs_info, + "suspicious: generation < chunk_root_generation: %llu < %llu", + btrfs_super_generation(sb), + btrfs_super_chunk_root_generation(sb)); + if (btrfs_super_generation(sb) < btrfs_super_cache_generation(sb) + && btrfs_super_cache_generation(sb) != (u64)-1) + btrfs_warn(fs_info, + "suspicious: generation < cache_generation: %llu < %llu", + btrfs_super_generation(sb), + btrfs_super_cache_generation(sb)); + + return ret; +} + +/* + * Validation of super block at mount time. + * Some checks already done early at mount time, like csum type and incompat + * flags will be skipped. + */ +static int btrfs_validate_mount_super(struct btrfs_fs_info *fs_info) +{ + return validate_super(fs_info, fs_info->super_copy, 0); +} + +/* + * Validation of super block at write time. + * Some checks like bytenr check will be skipped as their values will be + * overwritten soon. + * Extra checks like csum type and incompat flags will be done here. + */ +static int btrfs_validate_write_super(struct btrfs_fs_info *fs_info, + struct btrfs_super_block *sb) +{ + int ret; + + ret = validate_super(fs_info, sb, -1); + if (ret < 0) + goto out; + if (!btrfs_supported_super_csum(btrfs_super_csum_type(sb))) { + ret = -EUCLEAN; + btrfs_err(fs_info, "invalid csum type, has %u want %u", + btrfs_super_csum_type(sb), BTRFS_CSUM_TYPE_CRC32); + goto out; + } + if (btrfs_super_incompat_flags(sb) & ~BTRFS_FEATURE_INCOMPAT_SUPP) { + ret = -EUCLEAN; + btrfs_err(fs_info, + "invalid incompat flags, has 0x%llx valid mask 0x%llx", + btrfs_super_incompat_flags(sb), + (unsigned long long)BTRFS_FEATURE_INCOMPAT_SUPP); + goto out; + } +out: + if (ret < 0) + btrfs_err(fs_info, + "super block corruption detected before writing it to disk"); + return ret; +} + +static int __cold init_tree_roots(struct btrfs_fs_info *fs_info) +{ + int backup_index = find_newest_super_backup(fs_info); + struct btrfs_super_block *sb = fs_info->super_copy; + struct btrfs_root *tree_root = fs_info->tree_root; + bool handle_error = false; + int ret = 0; + int i; + + for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) { + u64 generation; + int level; + + if (handle_error) { + if (!IS_ERR(tree_root->node)) + free_extent_buffer(tree_root->node); + tree_root->node = NULL; + + if (!btrfs_test_opt(fs_info, USEBACKUPROOT)) + break; + + free_root_pointers(fs_info, 0); + + /* + * Don't use the log in recovery mode, it won't be + * valid + */ + btrfs_set_super_log_root(sb, 0); + + /* We can't trust the free space cache either */ + btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE); + + ret = read_backup_root(fs_info, i); + backup_index = ret; + if (ret < 0) + return ret; + } + generation = btrfs_super_generation(sb); + level = btrfs_super_root_level(sb); + tree_root->node = read_tree_block(fs_info, btrfs_super_root(sb), + generation, level, NULL); + if (IS_ERR(tree_root->node)) { + handle_error = true; + ret = PTR_ERR(tree_root->node); + tree_root->node = NULL; + btrfs_warn(fs_info, "couldn't read tree root"); + continue; + + } else if (!extent_buffer_uptodate(tree_root->node)) { + handle_error = true; + ret = -EIO; + btrfs_warn(fs_info, "error while reading tree root"); + continue; + } + + btrfs_set_root_node(&tree_root->root_item, tree_root->node); + tree_root->commit_root = btrfs_root_node(tree_root); + btrfs_set_root_refs(&tree_root->root_item, 1); + + /* + * No need to hold btrfs_root::objectid_mutex since the fs + * hasn't been fully initialised and we are the only user + */ + ret = btrfs_find_highest_objectid(tree_root, + &tree_root->highest_objectid); + if (ret < 0) { + handle_error = true; + continue; + } + + ASSERT(tree_root->highest_objectid <= BTRFS_LAST_FREE_OBJECTID); + + ret = btrfs_read_roots(fs_info); + if (ret < 0) { + handle_error = true; + continue; + } + + /* All successful */ + fs_info->generation = generation; + fs_info->last_trans_committed = generation; + + /* Always begin writing backup roots after the one being used */ + if (backup_index < 0) { + fs_info->backup_root_index = 0; + } else { + fs_info->backup_root_index = backup_index + 1; + fs_info->backup_root_index %= BTRFS_NUM_BACKUP_ROOTS; + } + break; + } + + return ret; +} + +void btrfs_init_fs_info(struct btrfs_fs_info *fs_info) +{ + INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC); + INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC); + INIT_LIST_HEAD(&fs_info->trans_list); + INIT_LIST_HEAD(&fs_info->dead_roots); + INIT_LIST_HEAD(&fs_info->delayed_iputs); + INIT_LIST_HEAD(&fs_info->delalloc_roots); + INIT_LIST_HEAD(&fs_info->caching_block_groups); + spin_lock_init(&fs_info->delalloc_root_lock); + spin_lock_init(&fs_info->trans_lock); + spin_lock_init(&fs_info->fs_roots_radix_lock); + spin_lock_init(&fs_info->delayed_iput_lock); + spin_lock_init(&fs_info->defrag_inodes_lock); + spin_lock_init(&fs_info->super_lock); + spin_lock_init(&fs_info->buffer_lock); + spin_lock_init(&fs_info->unused_bgs_lock); + rwlock_init(&fs_info->tree_mod_log_lock); + mutex_init(&fs_info->unused_bg_unpin_mutex); + mutex_init(&fs_info->delete_unused_bgs_mutex); + mutex_init(&fs_info->reloc_mutex); + mutex_init(&fs_info->delalloc_root_mutex); + seqlock_init(&fs_info->profiles_lock); + + INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots); + INIT_LIST_HEAD(&fs_info->space_info); + INIT_LIST_HEAD(&fs_info->tree_mod_seq_list); + INIT_LIST_HEAD(&fs_info->unused_bgs); +#ifdef CONFIG_BTRFS_DEBUG + INIT_LIST_HEAD(&fs_info->allocated_roots); + INIT_LIST_HEAD(&fs_info->allocated_ebs); + spin_lock_init(&fs_info->eb_leak_lock); +#endif + extent_map_tree_init(&fs_info->mapping_tree); + btrfs_init_block_rsv(&fs_info->global_block_rsv, + BTRFS_BLOCK_RSV_GLOBAL); + btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS); + btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK); + btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY); + btrfs_init_block_rsv(&fs_info->delayed_block_rsv, + BTRFS_BLOCK_RSV_DELOPS); + btrfs_init_block_rsv(&fs_info->delayed_refs_rsv, + BTRFS_BLOCK_RSV_DELREFS); + + atomic_set(&fs_info->async_delalloc_pages, 0); + atomic_set(&fs_info->defrag_running, 0); + atomic_set(&fs_info->reada_works_cnt, 0); + atomic_set(&fs_info->nr_delayed_iputs, 0); + atomic64_set(&fs_info->tree_mod_seq, 0); + fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE; + fs_info->metadata_ratio = 0; + fs_info->defrag_inodes = RB_ROOT; + atomic64_set(&fs_info->free_chunk_space, 0); + fs_info->tree_mod_log = RB_ROOT; + fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; + fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */ + /* readahead state */ + INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM); + spin_lock_init(&fs_info->reada_lock); + btrfs_init_ref_verify(fs_info); + + fs_info->thread_pool_size = min_t(unsigned long, + num_online_cpus() + 2, 8); + + INIT_LIST_HEAD(&fs_info->ordered_roots); + spin_lock_init(&fs_info->ordered_root_lock); + + btrfs_init_scrub(fs_info); +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + fs_info->check_integrity_print_mask = 0; +#endif + btrfs_init_balance(fs_info); + btrfs_init_async_reclaim_work(fs_info); + + spin_lock_init(&fs_info->block_group_cache_lock); + fs_info->block_group_cache_tree = RB_ROOT; + fs_info->first_logical_byte = (u64)-1; + + extent_io_tree_init(fs_info, &fs_info->excluded_extents, + IO_TREE_FS_EXCLUDED_EXTENTS, NULL); + set_bit(BTRFS_FS_BARRIER, &fs_info->flags); + + mutex_init(&fs_info->ordered_operations_mutex); + mutex_init(&fs_info->tree_log_mutex); + mutex_init(&fs_info->chunk_mutex); + mutex_init(&fs_info->transaction_kthread_mutex); + mutex_init(&fs_info->cleaner_mutex); + mutex_init(&fs_info->ro_block_group_mutex); + init_rwsem(&fs_info->commit_root_sem); + init_rwsem(&fs_info->cleanup_work_sem); + init_rwsem(&fs_info->subvol_sem); + sema_init(&fs_info->uuid_tree_rescan_sem, 1); + + btrfs_init_dev_replace_locks(fs_info); + btrfs_init_qgroup(fs_info); + btrfs_discard_init(fs_info); + + btrfs_init_free_cluster(&fs_info->meta_alloc_cluster); + btrfs_init_free_cluster(&fs_info->data_alloc_cluster); + + init_waitqueue_head(&fs_info->transaction_throttle); + init_waitqueue_head(&fs_info->transaction_wait); + init_waitqueue_head(&fs_info->transaction_blocked_wait); + init_waitqueue_head(&fs_info->async_submit_wait); + init_waitqueue_head(&fs_info->delayed_iputs_wait); + + /* Usable values until the real ones are cached from the superblock */ + fs_info->nodesize = 4096; + fs_info->sectorsize = 4096; + fs_info->stripesize = 4096; + + spin_lock_init(&fs_info->swapfile_pins_lock); + fs_info->swapfile_pins = RB_ROOT; + + fs_info->send_in_progress = 0; +} + +static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb) +{ + int ret; + + fs_info->sb = sb; + sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE; + sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE); + + ret = percpu_counter_init(&fs_info->dio_bytes, 0, GFP_KERNEL); + if (ret) + return ret; + + ret = percpu_counter_init(&fs_info->dirty_metadata_bytes, 0, GFP_KERNEL); + if (ret) + return ret; + + fs_info->dirty_metadata_batch = PAGE_SIZE * + (1 + ilog2(nr_cpu_ids)); + + ret = percpu_counter_init(&fs_info->delalloc_bytes, 0, GFP_KERNEL); + if (ret) + return ret; + + ret = percpu_counter_init(&fs_info->dev_replace.bio_counter, 0, + GFP_KERNEL); + if (ret) + return ret; + + fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root), + GFP_KERNEL); + if (!fs_info->delayed_root) + return -ENOMEM; + btrfs_init_delayed_root(fs_info->delayed_root); + + return btrfs_alloc_stripe_hash_table(fs_info); +} + +static int btrfs_uuid_rescan_kthread(void *data) +{ + struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data; + int ret; + + /* + * 1st step is to iterate through the existing UUID tree and + * to delete all entries that contain outdated data. + * 2nd step is to add all missing entries to the UUID tree. + */ + ret = btrfs_uuid_tree_iterate(fs_info); + if (ret < 0) { + if (ret != -EINTR) + btrfs_warn(fs_info, "iterating uuid_tree failed %d", + ret); + up(&fs_info->uuid_tree_rescan_sem); + return ret; + } + return btrfs_uuid_scan_kthread(data); +} + +static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info) +{ + struct task_struct *task; + + down(&fs_info->uuid_tree_rescan_sem); + task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid"); + if (IS_ERR(task)) { + /* fs_info->update_uuid_tree_gen remains 0 in all error case */ + btrfs_warn(fs_info, "failed to start uuid_rescan task"); + up(&fs_info->uuid_tree_rescan_sem); + return PTR_ERR(task); + } + + return 0; +} + +int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices, + char *options) +{ + u32 sectorsize; + u32 nodesize; + u32 stripesize; + u64 generation; + u64 features; + u16 csum_type; + struct btrfs_super_block *disk_super; + struct btrfs_fs_info *fs_info = btrfs_sb(sb); + struct btrfs_root *tree_root; + struct btrfs_root *chunk_root; + int ret; + int err = -EINVAL; + int clear_free_space_tree = 0; + int level; + + ret = init_mount_fs_info(fs_info, sb); + if (ret) { + err = ret; + goto fail; + } + + /* These need to be init'ed before we start creating inodes and such. */ + tree_root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, + GFP_KERNEL); + fs_info->tree_root = tree_root; + chunk_root = btrfs_alloc_root(fs_info, BTRFS_CHUNK_TREE_OBJECTID, + GFP_KERNEL); + fs_info->chunk_root = chunk_root; + if (!tree_root || !chunk_root) { + err = -ENOMEM; + goto fail; + } + + fs_info->btree_inode = new_inode(sb); + if (!fs_info->btree_inode) { + err = -ENOMEM; + goto fail; + } + mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS); + btrfs_init_btree_inode(fs_info); + + invalidate_bdev(fs_devices->latest_bdev); + + /* + * Read super block and check the signature bytes only + */ + disk_super = btrfs_read_dev_super(fs_devices->latest_bdev); + if (IS_ERR(disk_super)) { + err = PTR_ERR(disk_super); + goto fail_alloc; + } + + /* + * Verify the type first, if that or the checksum value are + * corrupted, we'll find out + */ + csum_type = btrfs_super_csum_type(disk_super); + if (!btrfs_supported_super_csum(csum_type)) { + btrfs_err(fs_info, "unsupported checksum algorithm: %u", + csum_type); + err = -EINVAL; + btrfs_release_disk_super(disk_super); + goto fail_alloc; + } + + ret = btrfs_init_csum_hash(fs_info, csum_type); + if (ret) { + err = ret; + btrfs_release_disk_super(disk_super); + goto fail_alloc; + } + + /* + * We want to check superblock checksum, the type is stored inside. + * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k). + */ + if (btrfs_check_super_csum(fs_info, (u8 *)disk_super)) { + btrfs_err(fs_info, "superblock checksum mismatch"); + err = -EINVAL; + btrfs_release_disk_super(disk_super); + goto fail_alloc; + } + + /* + * super_copy is zeroed at allocation time and we never touch the + * following bytes up to INFO_SIZE, the checksum is calculated from + * the whole block of INFO_SIZE + */ + memcpy(fs_info->super_copy, disk_super, sizeof(*fs_info->super_copy)); + btrfs_release_disk_super(disk_super); + + disk_super = fs_info->super_copy; + + + features = btrfs_super_flags(disk_super); + if (features & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) { + features &= ~BTRFS_SUPER_FLAG_CHANGING_FSID_V2; + btrfs_set_super_flags(disk_super, features); + btrfs_info(fs_info, + "found metadata UUID change in progress flag, clearing"); + } + + memcpy(fs_info->super_for_commit, fs_info->super_copy, + sizeof(*fs_info->super_for_commit)); + + ret = btrfs_validate_mount_super(fs_info); + if (ret) { + btrfs_err(fs_info, "superblock contains fatal errors"); + err = -EINVAL; + goto fail_alloc; + } + + if (!btrfs_super_root(disk_super)) + goto fail_alloc; + + /* check FS state, whether FS is broken. */ + if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR) + set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state); + + /* + * In the long term, we'll store the compression type in the super + * block, and it'll be used for per file compression control. + */ + fs_info->compress_type = BTRFS_COMPRESS_ZLIB; + + /* + * Flag our filesystem as having big metadata blocks if they are bigger + * than the page size + */ + if (btrfs_super_nodesize(disk_super) > PAGE_SIZE) { + if (!(features & BTRFS_FEATURE_INCOMPAT_BIG_METADATA)) + btrfs_info(fs_info, + "flagging fs with big metadata feature"); + features |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA; + } + + /* Set up fs_info before parsing mount options */ + nodesize = btrfs_super_nodesize(disk_super); + sectorsize = btrfs_super_sectorsize(disk_super); + stripesize = sectorsize; + fs_info->dirty_metadata_batch = nodesize * (1 + ilog2(nr_cpu_ids)); + fs_info->delalloc_batch = sectorsize * 512 * (1 + ilog2(nr_cpu_ids)); + + /* Cache block sizes */ + fs_info->nodesize = nodesize; + fs_info->sectorsize = sectorsize; + fs_info->stripesize = stripesize; + + ret = btrfs_parse_options(fs_info, options, sb->s_flags); + if (ret) { + err = ret; + goto fail_alloc; + } + + features = btrfs_super_incompat_flags(disk_super) & + ~BTRFS_FEATURE_INCOMPAT_SUPP; + if (features) { + btrfs_err(fs_info, + "cannot mount because of unsupported optional features (0x%llx)", + features); + err = -EINVAL; + goto fail_alloc; + } + + features = btrfs_super_incompat_flags(disk_super); + features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF; + if (fs_info->compress_type == BTRFS_COMPRESS_LZO) + features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO; + else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD) + features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD; + + if (features & BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA) + btrfs_info(fs_info, "has skinny extents"); + + /* + * mixed block groups end up with duplicate but slightly offset + * extent buffers for the same range. It leads to corruptions + */ + if ((features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) && + (sectorsize != nodesize)) { + btrfs_err(fs_info, +"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups", + nodesize, sectorsize); + goto fail_alloc; + } + + /* + * Needn't use the lock because there is no other task which will + * update the flag. + */ + btrfs_set_super_incompat_flags(disk_super, features); + + features = btrfs_super_compat_ro_flags(disk_super) & + ~BTRFS_FEATURE_COMPAT_RO_SUPP; + if (!sb_rdonly(sb) && features) { + btrfs_err(fs_info, + "cannot mount read-write because of unsupported optional features (0x%llx)", + features); + err = -EINVAL; + goto fail_alloc; + } + /* + * We have unsupported RO compat features, although RO mounted, we + * should not cause any metadata write, including log replay. + * Or we could screw up whatever the new feature requires. + */ + if (unlikely(features && btrfs_super_log_root(disk_super) && + !btrfs_test_opt(fs_info, NOLOGREPLAY))) { + btrfs_err(fs_info, +"cannot replay dirty log with unsupported compat_ro features (0x%llx), try rescue=nologreplay", + features); + err = -EINVAL; + goto fail_alloc; + } + + + ret = btrfs_init_workqueues(fs_info, fs_devices); + if (ret) { + err = ret; + goto fail_sb_buffer; + } + + sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super); + sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE); + + sb->s_blocksize = sectorsize; + sb->s_blocksize_bits = blksize_bits(sectorsize); + memcpy(&sb->s_uuid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE); + + mutex_lock(&fs_info->chunk_mutex); + ret = btrfs_read_sys_array(fs_info); + mutex_unlock(&fs_info->chunk_mutex); + if (ret) { + btrfs_err(fs_info, "failed to read the system array: %d", ret); + goto fail_sb_buffer; + } + + generation = btrfs_super_chunk_root_generation(disk_super); + level = btrfs_super_chunk_root_level(disk_super); + + chunk_root->node = read_tree_block(fs_info, + btrfs_super_chunk_root(disk_super), + generation, level, NULL); + if (IS_ERR(chunk_root->node) || + !extent_buffer_uptodate(chunk_root->node)) { + btrfs_err(fs_info, "failed to read chunk root"); + if (!IS_ERR(chunk_root->node)) + free_extent_buffer(chunk_root->node); + chunk_root->node = NULL; + goto fail_tree_roots; + } + btrfs_set_root_node(&chunk_root->root_item, chunk_root->node); + chunk_root->commit_root = btrfs_root_node(chunk_root); + + read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid, + offsetof(struct btrfs_header, chunk_tree_uuid), + BTRFS_UUID_SIZE); + + ret = btrfs_read_chunk_tree(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to read chunk tree: %d", ret); + goto fail_tree_roots; + } + + /* + * Keep the devid that is marked to be the target device for the + * device replace procedure + */ + btrfs_free_extra_devids(fs_devices, 0); + + if (!fs_devices->latest_bdev) { + btrfs_err(fs_info, "failed to read devices"); + goto fail_tree_roots; + } + + ret = init_tree_roots(fs_info); + if (ret) + goto fail_tree_roots; + + /* + * If we have a uuid root and we're not being told to rescan we need to + * check the generation here so we can set the + * BTRFS_FS_UPDATE_UUID_TREE_GEN bit. Otherwise we could commit the + * transaction during a balance or the log replay without updating the + * uuid generation, and then if we crash we would rescan the uuid tree, + * even though it was perfectly fine. + */ + if (fs_info->uuid_root && !btrfs_test_opt(fs_info, RESCAN_UUID_TREE) && + fs_info->generation == btrfs_super_uuid_tree_generation(disk_super)) + set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags); + + ret = btrfs_verify_dev_extents(fs_info); + if (ret) { + btrfs_err(fs_info, + "failed to verify dev extents against chunks: %d", + ret); + goto fail_block_groups; + } + ret = btrfs_recover_balance(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to recover balance: %d", ret); + goto fail_block_groups; + } + + ret = btrfs_init_dev_stats(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to init dev_stats: %d", ret); + goto fail_block_groups; + } + + ret = btrfs_init_dev_replace(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to init dev_replace: %d", ret); + goto fail_block_groups; + } + + btrfs_free_extra_devids(fs_devices, 1); + + ret = btrfs_sysfs_add_fsid(fs_devices); + if (ret) { + btrfs_err(fs_info, "failed to init sysfs fsid interface: %d", + ret); + goto fail_block_groups; + } + + ret = btrfs_sysfs_add_mounted(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to init sysfs interface: %d", ret); + goto fail_fsdev_sysfs; + } + + ret = btrfs_init_space_info(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to initialize space info: %d", ret); + goto fail_sysfs; + } + + ret = btrfs_read_block_groups(fs_info); + if (ret) { + btrfs_err(fs_info, "failed to read block groups: %d", ret); + goto fail_sysfs; + } + + if (!sb_rdonly(sb) && fs_info->fs_devices->missing_devices && + !btrfs_check_rw_degradable(fs_info, NULL)) { + btrfs_warn(fs_info, + "writable mount is not allowed due to too many missing devices"); + goto fail_sysfs; + } + + fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root, + "btrfs-cleaner"); + if (IS_ERR(fs_info->cleaner_kthread)) + goto fail_sysfs; + + fs_info->transaction_kthread = kthread_run(transaction_kthread, + tree_root, + "btrfs-transaction"); + if (IS_ERR(fs_info->transaction_kthread)) + goto fail_cleaner; + + if (!btrfs_test_opt(fs_info, NOSSD) && + !fs_info->fs_devices->rotating) { + btrfs_set_and_info(fs_info, SSD, "enabling ssd optimizations"); + } + + /* + * Mount does not set all options immediately, we can do it now and do + * not have to wait for transaction commit + */ + btrfs_apply_pending_changes(fs_info); + +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) { + ret = btrfsic_mount(fs_info, fs_devices, + btrfs_test_opt(fs_info, + CHECK_INTEGRITY_INCLUDING_EXTENT_DATA) ? + 1 : 0, + fs_info->check_integrity_print_mask); + if (ret) + btrfs_warn(fs_info, + "failed to initialize integrity check module: %d", + ret); + } +#endif + ret = btrfs_read_qgroup_config(fs_info); + if (ret) + goto fail_trans_kthread; + + if (btrfs_build_ref_tree(fs_info)) + btrfs_err(fs_info, "couldn't build ref tree"); + + /* do not make disk changes in broken FS or nologreplay is given */ + if (btrfs_super_log_root(disk_super) != 0 && + !btrfs_test_opt(fs_info, NOLOGREPLAY)) { + btrfs_info(fs_info, "start tree-log replay"); + ret = btrfs_replay_log(fs_info, fs_devices); + if (ret) { + err = ret; + goto fail_qgroup; + } + } + + ret = btrfs_find_orphan_roots(fs_info); + if (ret) + goto fail_qgroup; + + if (!sb_rdonly(sb)) { + ret = btrfs_cleanup_fs_roots(fs_info); + if (ret) + goto fail_qgroup; + + mutex_lock(&fs_info->cleaner_mutex); + ret = btrfs_recover_relocation(tree_root); + mutex_unlock(&fs_info->cleaner_mutex); + if (ret < 0) { + btrfs_warn(fs_info, "failed to recover relocation: %d", + ret); + err = -EINVAL; + goto fail_qgroup; + } + } + + fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true); + if (IS_ERR(fs_info->fs_root)) { + err = PTR_ERR(fs_info->fs_root); + btrfs_warn(fs_info, "failed to read fs tree: %d", err); + fs_info->fs_root = NULL; + goto fail_qgroup; + } + + if (sb_rdonly(sb)) + return 0; + + if (btrfs_test_opt(fs_info, CLEAR_CACHE) && + btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + clear_free_space_tree = 1; + } else if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) && + !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID)) { + btrfs_warn(fs_info, "free space tree is invalid"); + clear_free_space_tree = 1; + } + + if (clear_free_space_tree) { + btrfs_info(fs_info, "clearing free space tree"); + ret = btrfs_clear_free_space_tree(fs_info); + if (ret) { + btrfs_warn(fs_info, + "failed to clear free space tree: %d", ret); + close_ctree(fs_info); + return ret; + } + } + + if (btrfs_test_opt(fs_info, FREE_SPACE_TREE) && + !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + btrfs_info(fs_info, "creating free space tree"); + ret = btrfs_create_free_space_tree(fs_info); + if (ret) { + btrfs_warn(fs_info, + "failed to create free space tree: %d", ret); + close_ctree(fs_info); + return ret; + } + } + + down_read(&fs_info->cleanup_work_sem); + if ((ret = btrfs_orphan_cleanup(fs_info->fs_root)) || + (ret = btrfs_orphan_cleanup(fs_info->tree_root))) { + up_read(&fs_info->cleanup_work_sem); + close_ctree(fs_info); + return ret; + } + up_read(&fs_info->cleanup_work_sem); + + ret = btrfs_resume_balance_async(fs_info); + if (ret) { + btrfs_warn(fs_info, "failed to resume balance: %d", ret); + close_ctree(fs_info); + return ret; + } + + ret = btrfs_resume_dev_replace_async(fs_info); + if (ret) { + btrfs_warn(fs_info, "failed to resume device replace: %d", ret); + close_ctree(fs_info); + return ret; + } + + btrfs_qgroup_rescan_resume(fs_info); + btrfs_discard_resume(fs_info); + + if (!fs_info->uuid_root) { + btrfs_info(fs_info, "creating UUID tree"); + ret = btrfs_create_uuid_tree(fs_info); + if (ret) { + btrfs_warn(fs_info, + "failed to create the UUID tree: %d", ret); + close_ctree(fs_info); + return ret; + } + } else if (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) || + fs_info->generation != + btrfs_super_uuid_tree_generation(disk_super)) { + btrfs_info(fs_info, "checking UUID tree"); + ret = btrfs_check_uuid_tree(fs_info); + if (ret) { + btrfs_warn(fs_info, + "failed to check the UUID tree: %d", ret); + close_ctree(fs_info); + return ret; + } + } + set_bit(BTRFS_FS_OPEN, &fs_info->flags); + + /* + * backuproot only affect mount behavior, and if open_ctree succeeded, + * no need to keep the flag + */ + btrfs_clear_opt(fs_info->mount_opt, USEBACKUPROOT); + + return 0; + +fail_qgroup: + btrfs_free_qgroup_config(fs_info); +fail_trans_kthread: + kthread_stop(fs_info->transaction_kthread); + btrfs_cleanup_transaction(fs_info); + btrfs_free_fs_roots(fs_info); +fail_cleaner: + kthread_stop(fs_info->cleaner_kthread); + + /* + * make sure we're done with the btree inode before we stop our + * kthreads + */ + filemap_write_and_wait(fs_info->btree_inode->i_mapping); + +fail_sysfs: + btrfs_sysfs_remove_mounted(fs_info); + +fail_fsdev_sysfs: + btrfs_sysfs_remove_fsid(fs_info->fs_devices); + +fail_block_groups: + btrfs_put_block_group_cache(fs_info); + +fail_tree_roots: + if (fs_info->data_reloc_root) + btrfs_drop_and_free_fs_root(fs_info, fs_info->data_reloc_root); + free_root_pointers(fs_info, true); + invalidate_inode_pages2(fs_info->btree_inode->i_mapping); + +fail_sb_buffer: + btrfs_stop_all_workers(fs_info); + btrfs_free_block_groups(fs_info); +fail_alloc: + btrfs_mapping_tree_free(&fs_info->mapping_tree); + + iput(fs_info->btree_inode); +fail: + btrfs_close_devices(fs_info->fs_devices); + return err; +} +ALLOW_ERROR_INJECTION(open_ctree, ERRNO); + +static void btrfs_end_super_write(struct bio *bio) +{ + struct btrfs_device *device = bio->bi_private; + struct bio_vec *bvec; + struct bvec_iter_all iter_all; + struct page *page; + + bio_for_each_segment_all(bvec, bio, iter_all) { + page = bvec->bv_page; + + if (bio->bi_status) { + btrfs_warn_rl_in_rcu(device->fs_info, + "lost page write due to IO error on %s (%d)", + rcu_str_deref(device->name), + blk_status_to_errno(bio->bi_status)); + ClearPageUptodate(page); + SetPageError(page); + btrfs_dev_stat_inc_and_print(device, + BTRFS_DEV_STAT_WRITE_ERRS); + } else { + SetPageUptodate(page); + } + + put_page(page); + unlock_page(page); + } + + bio_put(bio); +} + +struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev, + int copy_num) +{ + struct btrfs_super_block *super; + struct page *page; + u64 bytenr; + struct address_space *mapping = bdev->bd_inode->i_mapping; + + bytenr = btrfs_sb_offset(copy_num); + if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode)) + return ERR_PTR(-EINVAL); + + page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS); + if (IS_ERR(page)) + return ERR_CAST(page); + + super = page_address(page); + if (btrfs_super_magic(super) != BTRFS_MAGIC) { + btrfs_release_disk_super(super); + return ERR_PTR(-ENODATA); + } + + if (btrfs_super_bytenr(super) != bytenr) { + btrfs_release_disk_super(super); + return ERR_PTR(-EINVAL); + } + + return super; +} + + +struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev) +{ + struct btrfs_super_block *super, *latest = NULL; + int i; + u64 transid = 0; + + /* we would like to check all the supers, but that would make + * a btrfs mount succeed after a mkfs from a different FS. + * So, we need to add a special mount option to scan for + * later supers, using BTRFS_SUPER_MIRROR_MAX instead + */ + for (i = 0; i < 1; i++) { + super = btrfs_read_dev_one_super(bdev, i); + if (IS_ERR(super)) + continue; + + if (!latest || btrfs_super_generation(super) > transid) { + if (latest) + btrfs_release_disk_super(super); + + latest = super; + transid = btrfs_super_generation(super); + } + } + + return super; +} + +/* + * Write superblock @sb to the @device. Do not wait for completion, all the + * pages we use for writing are locked. + * + * Write @max_mirrors copies of the superblock, where 0 means default that fit + * the expected device size at commit time. Note that max_mirrors must be + * same for write and wait phases. + * + * Return number of errors when page is not found or submission fails. + */ +static int write_dev_supers(struct btrfs_device *device, + struct btrfs_super_block *sb, int max_mirrors) +{ + struct btrfs_fs_info *fs_info = device->fs_info; + struct address_space *mapping = device->bdev->bd_inode->i_mapping; + SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); + int i; + int errors = 0; + u64 bytenr; + + if (max_mirrors == 0) + max_mirrors = BTRFS_SUPER_MIRROR_MAX; + + shash->tfm = fs_info->csum_shash; + + for (i = 0; i < max_mirrors; i++) { + struct page *page; + struct bio *bio; + struct btrfs_super_block *disk_super; + + bytenr = btrfs_sb_offset(i); + if (bytenr + BTRFS_SUPER_INFO_SIZE >= + device->commit_total_bytes) + break; + + btrfs_set_super_bytenr(sb, bytenr); + + crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE, + BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, + sb->csum); + + page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT, + GFP_NOFS); + if (!page) { + btrfs_err(device->fs_info, + "couldn't get super block page for bytenr %llu", + bytenr); + errors++; + continue; + } + + /* Bump the refcount for wait_dev_supers() */ + get_page(page); + + disk_super = page_address(page); + memcpy(disk_super, sb, BTRFS_SUPER_INFO_SIZE); + + /* + * Directly use bios here instead of relying on the page cache + * to do I/O, so we don't lose the ability to do integrity + * checking. + */ + bio = bio_alloc(GFP_NOFS, 1); + bio_set_dev(bio, device->bdev); + bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT; + bio->bi_private = device; + bio->bi_end_io = btrfs_end_super_write; + __bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE, + offset_in_page(bytenr)); + + /* + * We FUA only the first super block. The others we allow to + * go down lazy and there's a short window where the on-disk + * copies might still contain the older version. + */ + bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO; + if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER)) + bio->bi_opf |= REQ_FUA; + + btrfsic_submit_bio(bio); + } + return errors < i ? 0 : -1; +} + +/* + * Wait for write completion of superblocks done by write_dev_supers, + * @max_mirrors same for write and wait phases. + * + * Return number of errors when page is not found or not marked up to + * date. + */ +static int wait_dev_supers(struct btrfs_device *device, int max_mirrors) +{ + int i; + int errors = 0; + bool primary_failed = false; + u64 bytenr; + + if (max_mirrors == 0) + max_mirrors = BTRFS_SUPER_MIRROR_MAX; + + for (i = 0; i < max_mirrors; i++) { + struct page *page; + + bytenr = btrfs_sb_offset(i); + if (bytenr + BTRFS_SUPER_INFO_SIZE >= + device->commit_total_bytes) + break; + + page = find_get_page(device->bdev->bd_inode->i_mapping, + bytenr >> PAGE_SHIFT); + if (!page) { + errors++; + if (i == 0) + primary_failed = true; + continue; + } + /* Page is submitted locked and unlocked once the IO completes */ + wait_on_page_locked(page); + if (PageError(page)) { + errors++; + if (i == 0) + primary_failed = true; + } + + /* Drop our reference */ + put_page(page); + + /* Drop the reference from the writing run */ + put_page(page); + } + + /* log error, force error return */ + if (primary_failed) { + btrfs_err(device->fs_info, "error writing primary super block to device %llu", + device->devid); + return -1; + } + + return errors < i ? 0 : -1; +} + +/* + * endio for the write_dev_flush, this will wake anyone waiting + * for the barrier when it is done + */ +static void btrfs_end_empty_barrier(struct bio *bio) +{ + complete(bio->bi_private); +} + +/* + * Submit a flush request to the device if it supports it. Error handling is + * done in the waiting counterpart. + */ +static void write_dev_flush(struct btrfs_device *device) +{ + struct bio *bio = device->flush_bio; + +#ifndef CONFIG_BTRFS_FS_CHECK_INTEGRITY + /* + * When a disk has write caching disabled, we skip submission of a bio + * with flush and sync requests before writing the superblock, since + * it's not needed. However when the integrity checker is enabled, this + * results in reports that there are metadata blocks referred by a + * superblock that were not properly flushed. So don't skip the bio + * submission only when the integrity checker is enabled for the sake + * of simplicity, since this is a debug tool and not meant for use in + * non-debug builds. + */ + struct request_queue *q = bdev_get_queue(device->bdev); + if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) + return; +#endif + + bio_reset(bio); + bio->bi_end_io = btrfs_end_empty_barrier; + bio_set_dev(bio, device->bdev); + bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH; + init_completion(&device->flush_wait); + bio->bi_private = &device->flush_wait; + + btrfsic_submit_bio(bio); + set_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state); +} + +/* + * If the flush bio has been submitted by write_dev_flush, wait for it. + */ +static blk_status_t wait_dev_flush(struct btrfs_device *device) +{ + struct bio *bio = device->flush_bio; + + if (!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state)) + return BLK_STS_OK; + + clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state); + wait_for_completion_io(&device->flush_wait); + + return bio->bi_status; +} + +static int check_barrier_error(struct btrfs_fs_info *fs_info) +{ + if (!btrfs_check_rw_degradable(fs_info, NULL)) + return -EIO; + return 0; +} + +/* + * send an empty flush down to each device in parallel, + * then wait for them + */ +static int barrier_all_devices(struct btrfs_fs_info *info) +{ + struct list_head *head; + struct btrfs_device *dev; + int errors_wait = 0; + blk_status_t ret; + + lockdep_assert_held(&info->fs_devices->device_list_mutex); + /* send down all the barriers */ + head = &info->fs_devices->devices; + list_for_each_entry(dev, head, dev_list) { + if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) + continue; + if (!dev->bdev) + continue; + if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) || + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) + continue; + + write_dev_flush(dev); + dev->last_flush_error = BLK_STS_OK; + } + + /* wait for all the barriers */ + list_for_each_entry(dev, head, dev_list) { + if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) + continue; + if (!dev->bdev) { + errors_wait++; + continue; + } + if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) || + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) + continue; + + ret = wait_dev_flush(dev); + if (ret) { + dev->last_flush_error = ret; + btrfs_dev_stat_inc_and_print(dev, + BTRFS_DEV_STAT_FLUSH_ERRS); + errors_wait++; + } + } + + if (errors_wait) { + /* + * At some point we need the status of all disks + * to arrive at the volume status. So error checking + * is being pushed to a separate loop. + */ + return check_barrier_error(info); + } + return 0; +} + +int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags) +{ + int raid_type; + int min_tolerated = INT_MAX; + + if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 || + (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE)) + min_tolerated = min_t(int, min_tolerated, + btrfs_raid_array[BTRFS_RAID_SINGLE]. + tolerated_failures); + + for (raid_type = 0; raid_type < BTRFS_NR_RAID_TYPES; raid_type++) { + if (raid_type == BTRFS_RAID_SINGLE) + continue; + if (!(flags & btrfs_raid_array[raid_type].bg_flag)) + continue; + min_tolerated = min_t(int, min_tolerated, + btrfs_raid_array[raid_type]. + tolerated_failures); + } + + if (min_tolerated == INT_MAX) { + pr_warn("BTRFS: unknown raid flag: %llu", flags); + min_tolerated = 0; + } + + return min_tolerated; +} + +int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors) +{ + struct list_head *head; + struct btrfs_device *dev; + struct btrfs_super_block *sb; + struct btrfs_dev_item *dev_item; + int ret; + int do_barriers; + int max_errors; + int total_errors = 0; + u64 flags; + + do_barriers = !btrfs_test_opt(fs_info, NOBARRIER); + + /* + * max_mirrors == 0 indicates we're from commit_transaction, + * not from fsync where the tree roots in fs_info have not + * been consistent on disk. + */ + if (max_mirrors == 0) + backup_super_roots(fs_info); + + sb = fs_info->super_for_commit; + dev_item = &sb->dev_item; + + mutex_lock(&fs_info->fs_devices->device_list_mutex); + head = &fs_info->fs_devices->devices; + max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1; + + if (do_barriers) { + ret = barrier_all_devices(fs_info); + if (ret) { + mutex_unlock( + &fs_info->fs_devices->device_list_mutex); + btrfs_handle_fs_error(fs_info, ret, + "errors while submitting device barriers."); + return ret; + } + } + + list_for_each_entry(dev, head, dev_list) { + if (!dev->bdev) { + total_errors++; + continue; + } + if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) || + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) + continue; + + btrfs_set_stack_device_generation(dev_item, 0); + btrfs_set_stack_device_type(dev_item, dev->type); + btrfs_set_stack_device_id(dev_item, dev->devid); + btrfs_set_stack_device_total_bytes(dev_item, + dev->commit_total_bytes); + btrfs_set_stack_device_bytes_used(dev_item, + dev->commit_bytes_used); + btrfs_set_stack_device_io_align(dev_item, dev->io_align); + btrfs_set_stack_device_io_width(dev_item, dev->io_width); + btrfs_set_stack_device_sector_size(dev_item, dev->sector_size); + memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE); + memcpy(dev_item->fsid, dev->fs_devices->metadata_uuid, + BTRFS_FSID_SIZE); + + flags = btrfs_super_flags(sb); + btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN); + + ret = btrfs_validate_write_super(fs_info, sb); + if (ret < 0) { + mutex_unlock(&fs_info->fs_devices->device_list_mutex); + btrfs_handle_fs_error(fs_info, -EUCLEAN, + "unexpected superblock corruption detected"); + return -EUCLEAN; + } + + ret = write_dev_supers(dev, sb, max_mirrors); + if (ret) + total_errors++; + } + if (total_errors > max_errors) { + btrfs_err(fs_info, "%d errors while writing supers", + total_errors); + mutex_unlock(&fs_info->fs_devices->device_list_mutex); + + /* FUA is masked off if unsupported and can't be the reason */ + btrfs_handle_fs_error(fs_info, -EIO, + "%d errors while writing supers", + total_errors); + return -EIO; + } + + total_errors = 0; + list_for_each_entry(dev, head, dev_list) { + if (!dev->bdev) + continue; + if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) || + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) + continue; + + ret = wait_dev_supers(dev, max_mirrors); + if (ret) + total_errors++; + } + mutex_unlock(&fs_info->fs_devices->device_list_mutex); + if (total_errors > max_errors) { + btrfs_handle_fs_error(fs_info, -EIO, + "%d errors while writing supers", + total_errors); + return -EIO; + } + return 0; +} + +/* Drop a fs root from the radix tree and free it. */ +void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, + struct btrfs_root *root) +{ + bool drop_ref = false; + + spin_lock(&fs_info->fs_roots_radix_lock); + radix_tree_delete(&fs_info->fs_roots_radix, + (unsigned long)root->root_key.objectid); + if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state)) + drop_ref = true; + spin_unlock(&fs_info->fs_roots_radix_lock); + + if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { + ASSERT(root->log_root == NULL); + if (root->reloc_root) { + btrfs_put_root(root->reloc_root); + root->reloc_root = NULL; + } + } + + if (root->free_ino_pinned) + __btrfs_remove_free_space_cache(root->free_ino_pinned); + if (root->free_ino_ctl) + __btrfs_remove_free_space_cache(root->free_ino_ctl); + if (root->ino_cache_inode) { + iput(root->ino_cache_inode); + root->ino_cache_inode = NULL; + } + if (drop_ref) + btrfs_put_root(root); +} + +int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info) +{ + u64 root_objectid = 0; + struct btrfs_root *gang[8]; + int i = 0; + int err = 0; + unsigned int ret = 0; + + while (1) { + spin_lock(&fs_info->fs_roots_radix_lock); + ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, + (void **)gang, root_objectid, + ARRAY_SIZE(gang)); + if (!ret) { + spin_unlock(&fs_info->fs_roots_radix_lock); + break; + } + root_objectid = gang[ret - 1]->root_key.objectid + 1; + + for (i = 0; i < ret; i++) { + /* Avoid to grab roots in dead_roots */ + if (btrfs_root_refs(&gang[i]->root_item) == 0) { + gang[i] = NULL; + continue; + } + /* grab all the search result for later use */ + gang[i] = btrfs_grab_root(gang[i]); + } + spin_unlock(&fs_info->fs_roots_radix_lock); + + for (i = 0; i < ret; i++) { + if (!gang[i]) + continue; + root_objectid = gang[i]->root_key.objectid; + err = btrfs_orphan_cleanup(gang[i]); + if (err) + break; + btrfs_put_root(gang[i]); + } + root_objectid++; + } + + /* release the uncleaned roots due to error */ + for (; i < ret; i++) { + if (gang[i]) + btrfs_put_root(gang[i]); + } + return err; +} + +int btrfs_commit_super(struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *root = fs_info->tree_root; + struct btrfs_trans_handle *trans; + + mutex_lock(&fs_info->cleaner_mutex); + btrfs_run_delayed_iputs(fs_info); + mutex_unlock(&fs_info->cleaner_mutex); + wake_up_process(fs_info->cleaner_kthread); + + /* wait until ongoing cleanup work done */ + down_write(&fs_info->cleanup_work_sem); + up_write(&fs_info->cleanup_work_sem); + + trans = btrfs_join_transaction(root); + if (IS_ERR(trans)) + return PTR_ERR(trans); + return btrfs_commit_transaction(trans); +} + +void __cold close_ctree(struct btrfs_fs_info *fs_info) +{ + int ret; + + set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags); + /* + * We don't want the cleaner to start new transactions, add more delayed + * iputs, etc. while we're closing. We can't use kthread_stop() yet + * because that frees the task_struct, and the transaction kthread might + * still try to wake up the cleaner. + */ + kthread_park(fs_info->cleaner_kthread); + + /* wait for the qgroup rescan worker to stop */ + btrfs_qgroup_wait_for_completion(fs_info, false); + + /* wait for the uuid_scan task to finish */ + down(&fs_info->uuid_tree_rescan_sem); + /* avoid complains from lockdep et al., set sem back to initial state */ + up(&fs_info->uuid_tree_rescan_sem); + + /* pause restriper - we want to resume on mount */ + btrfs_pause_balance(fs_info); + + btrfs_dev_replace_suspend_for_unmount(fs_info); + + btrfs_scrub_cancel(fs_info); + + /* wait for any defraggers to finish */ + wait_event(fs_info->transaction_wait, + (atomic_read(&fs_info->defrag_running) == 0)); + + /* clear out the rbtree of defraggable inodes */ + btrfs_cleanup_defrag_inodes(fs_info); + + /* + * After we parked the cleaner kthread, ordered extents may have + * completed and created new delayed iputs. If one of the async reclaim + * tasks is running and in the RUN_DELAYED_IPUTS flush state, then we + * can hang forever trying to stop it, because if a delayed iput is + * added after it ran btrfs_run_delayed_iputs() and before it called + * btrfs_wait_on_delayed_iputs(), it will hang forever since there is + * no one else to run iputs. + * + * So wait for all ongoing ordered extents to complete and then run + * delayed iputs. This works because once we reach this point no one + * can either create new ordered extents nor create delayed iputs + * through some other means. + * + * Also note that btrfs_wait_ordered_roots() is not safe here, because + * it waits for BTRFS_ORDERED_COMPLETE to be set on an ordered extent, + * but the delayed iput for the respective inode is made only when doing + * the final btrfs_put_ordered_extent() (which must happen at + * btrfs_finish_ordered_io() when we are unmounting). + */ + btrfs_flush_workqueue(fs_info->endio_write_workers); + /* Ordered extents for free space inodes. */ + btrfs_flush_workqueue(fs_info->endio_freespace_worker); + btrfs_run_delayed_iputs(fs_info); + + cancel_work_sync(&fs_info->async_reclaim_work); + cancel_work_sync(&fs_info->async_data_reclaim_work); + + /* Cancel or finish ongoing discard work */ + btrfs_discard_cleanup(fs_info); + + if (!sb_rdonly(fs_info->sb)) { + /* + * The cleaner kthread is stopped, so do one final pass over + * unused block groups. + */ + btrfs_delete_unused_bgs(fs_info); + + /* + * There might be existing delayed inode workers still running + * and holding an empty delayed inode item. We must wait for + * them to complete first because they can create a transaction. + * This happens when someone calls btrfs_balance_delayed_items() + * and then a transaction commit runs the same delayed nodes + * before any delayed worker has done something with the nodes. + * We must wait for any worker here and not at transaction + * commit time since that could cause a deadlock. + * This is a very rare case. + */ + btrfs_flush_workqueue(fs_info->delayed_workers); + + ret = btrfs_commit_super(fs_info); + if (ret) + btrfs_err(fs_info, "commit super ret %d", ret); + } + + if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state) || + test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &fs_info->fs_state)) + btrfs_error_commit_super(fs_info); + + kthread_stop(fs_info->transaction_kthread); + kthread_stop(fs_info->cleaner_kthread); + + ASSERT(list_empty(&fs_info->delayed_iputs)); + set_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags); + + if (btrfs_check_quota_leak(fs_info)) { + WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG)); + btrfs_err(fs_info, "qgroup reserved space leaked"); + } + + btrfs_free_qgroup_config(fs_info); + ASSERT(list_empty(&fs_info->delalloc_roots)); + + if (percpu_counter_sum(&fs_info->delalloc_bytes)) { + btrfs_info(fs_info, "at unmount delalloc count %lld", + percpu_counter_sum(&fs_info->delalloc_bytes)); + } + + if (percpu_counter_sum(&fs_info->dio_bytes)) + btrfs_info(fs_info, "at unmount dio bytes count %lld", + percpu_counter_sum(&fs_info->dio_bytes)); + + btrfs_sysfs_remove_mounted(fs_info); + btrfs_sysfs_remove_fsid(fs_info->fs_devices); + + btrfs_put_block_group_cache(fs_info); + + /* + * we must make sure there is not any read request to + * submit after we stopping all workers. + */ + invalidate_inode_pages2(fs_info->btree_inode->i_mapping); + btrfs_stop_all_workers(fs_info); + + clear_bit(BTRFS_FS_OPEN, &fs_info->flags); + free_root_pointers(fs_info, true); + btrfs_free_fs_roots(fs_info); + + /* + * We must free the block groups after dropping the fs_roots as we could + * have had an IO error and have left over tree log blocks that aren't + * cleaned up until the fs roots are freed. This makes the block group + * accounting appear to be wrong because there's pending reserved bytes, + * so make sure we do the block group cleanup afterwards. + */ + btrfs_free_block_groups(fs_info); + + iput(fs_info->btree_inode); + +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + if (btrfs_test_opt(fs_info, CHECK_INTEGRITY)) + btrfsic_unmount(fs_info->fs_devices); +#endif + + btrfs_mapping_tree_free(&fs_info->mapping_tree); + btrfs_close_devices(fs_info->fs_devices); +} + +int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, + int atomic) +{ + int ret; + struct inode *btree_inode = buf->pages[0]->mapping->host; + + ret = extent_buffer_uptodate(buf); + if (!ret) + return ret; + + ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf, + parent_transid, atomic); + if (ret == -EAGAIN) + return ret; + return !ret; +} + +void btrfs_mark_buffer_dirty(struct extent_buffer *buf) +{ + struct btrfs_fs_info *fs_info; + struct btrfs_root *root; + u64 transid = btrfs_header_generation(buf); + int was_dirty; + +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS + /* + * This is a fast path so only do this check if we have sanity tests + * enabled. Normal people shouldn't be using unmapped buffers as dirty + * outside of the sanity tests. + */ + if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &buf->bflags))) + return; +#endif + root = BTRFS_I(buf->pages[0]->mapping->host)->root; + fs_info = root->fs_info; + btrfs_assert_tree_locked(buf); + if (transid != fs_info->generation) + WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, found %llu running %llu\n", + buf->start, transid, fs_info->generation); + was_dirty = set_extent_buffer_dirty(buf); + if (!was_dirty) + percpu_counter_add_batch(&fs_info->dirty_metadata_bytes, + buf->len, + fs_info->dirty_metadata_batch); +#ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY + /* + * Since btrfs_mark_buffer_dirty() can be called with item pointer set + * but item data not updated. + * So here we should only check item pointers, not item data. + */ + if (btrfs_header_level(buf) == 0 && + btrfs_check_leaf_relaxed(buf)) { + btrfs_print_leaf(buf); + ASSERT(0); + } +#endif +} + +static void __btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info, + int flush_delayed) +{ + /* + * looks as though older kernels can get into trouble with + * this code, they end up stuck in balance_dirty_pages forever + */ + int ret; + + if (current->flags & PF_MEMALLOC) + return; + + if (flush_delayed) + btrfs_balance_delayed_items(fs_info); + + ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes, + BTRFS_DIRTY_METADATA_THRESH, + fs_info->dirty_metadata_batch); + if (ret > 0) { + balance_dirty_pages_ratelimited(fs_info->btree_inode->i_mapping); + } +} + +void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info) +{ + __btrfs_btree_balance_dirty(fs_info, 1); +} + +void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info) +{ + __btrfs_btree_balance_dirty(fs_info, 0); +} + +int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level, + struct btrfs_key *first_key) +{ + return btree_read_extent_buffer_pages(buf, parent_transid, + level, first_key); +} + +static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info) +{ + /* cleanup FS via transaction */ + btrfs_cleanup_transaction(fs_info); + + mutex_lock(&fs_info->cleaner_mutex); + btrfs_run_delayed_iputs(fs_info); + mutex_unlock(&fs_info->cleaner_mutex); + + down_write(&fs_info->cleanup_work_sem); + up_write(&fs_info->cleanup_work_sem); +} + +static void btrfs_drop_all_logs(struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *gang[8]; + u64 root_objectid = 0; + int ret; + + spin_lock(&fs_info->fs_roots_radix_lock); + while ((ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, + (void **)gang, root_objectid, + ARRAY_SIZE(gang))) != 0) { + int i; + + for (i = 0; i < ret; i++) + gang[i] = btrfs_grab_root(gang[i]); + spin_unlock(&fs_info->fs_roots_radix_lock); + + for (i = 0; i < ret; i++) { + if (!gang[i]) + continue; + root_objectid = gang[i]->root_key.objectid; + btrfs_free_log(NULL, gang[i]); + btrfs_put_root(gang[i]); + } + root_objectid++; + spin_lock(&fs_info->fs_roots_radix_lock); + } + spin_unlock(&fs_info->fs_roots_radix_lock); + btrfs_free_log_root_tree(NULL, fs_info); +} + +static void btrfs_destroy_ordered_extents(struct btrfs_root *root) +{ + struct btrfs_ordered_extent *ordered; + + spin_lock(&root->ordered_extent_lock); + /* + * This will just short circuit the ordered completion stuff which will + * make sure the ordered extent gets properly cleaned up. + */ + list_for_each_entry(ordered, &root->ordered_extents, + root_extent_list) + set_bit(BTRFS_ORDERED_IOERR, &ordered->flags); + spin_unlock(&root->ordered_extent_lock); +} + +static void btrfs_destroy_all_ordered_extents(struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *root; + struct list_head splice; + + INIT_LIST_HEAD(&splice); + + spin_lock(&fs_info->ordered_root_lock); + list_splice_init(&fs_info->ordered_roots, &splice); + while (!list_empty(&splice)) { + root = list_first_entry(&splice, struct btrfs_root, + ordered_root); + list_move_tail(&root->ordered_root, + &fs_info->ordered_roots); + + spin_unlock(&fs_info->ordered_root_lock); + btrfs_destroy_ordered_extents(root); + + cond_resched(); + spin_lock(&fs_info->ordered_root_lock); + } + spin_unlock(&fs_info->ordered_root_lock); + + /* + * We need this here because if we've been flipped read-only we won't + * get sync() from the umount, so we need to make sure any ordered + * extents that haven't had their dirty pages IO start writeout yet + * actually get run and error out properly. + */ + btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); +} + +static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans, + struct btrfs_fs_info *fs_info) +{ + struct rb_node *node; + struct btrfs_delayed_ref_root *delayed_refs; + struct btrfs_delayed_ref_node *ref; + int ret = 0; + + delayed_refs = &trans->delayed_refs; + + spin_lock(&delayed_refs->lock); + if (atomic_read(&delayed_refs->num_entries) == 0) { + spin_unlock(&delayed_refs->lock); + btrfs_debug(fs_info, "delayed_refs has NO entry"); + return ret; + } + + while ((node = rb_first_cached(&delayed_refs->href_root)) != NULL) { + struct btrfs_delayed_ref_head *head; + struct rb_node *n; + bool pin_bytes = false; + + head = rb_entry(node, struct btrfs_delayed_ref_head, + href_node); + if (btrfs_delayed_ref_lock(delayed_refs, head)) + continue; + + spin_lock(&head->lock); + while ((n = rb_first_cached(&head->ref_tree)) != NULL) { + ref = rb_entry(n, struct btrfs_delayed_ref_node, + ref_node); + ref->in_tree = 0; + rb_erase_cached(&ref->ref_node, &head->ref_tree); + RB_CLEAR_NODE(&ref->ref_node); + if (!list_empty(&ref->add_list)) + list_del(&ref->add_list); + atomic_dec(&delayed_refs->num_entries); + btrfs_put_delayed_ref(ref); + } + if (head->must_insert_reserved) + pin_bytes = true; + btrfs_free_delayed_extent_op(head->extent_op); + btrfs_delete_ref_head(delayed_refs, head); + spin_unlock(&head->lock); + spin_unlock(&delayed_refs->lock); + mutex_unlock(&head->mutex); + + if (pin_bytes) { + struct btrfs_block_group *cache; + + cache = btrfs_lookup_block_group(fs_info, head->bytenr); + BUG_ON(!cache); + + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + cache->pinned += head->num_bytes; + btrfs_space_info_update_bytes_pinned(fs_info, + cache->space_info, head->num_bytes); + cache->reserved -= head->num_bytes; + cache->space_info->bytes_reserved -= head->num_bytes; + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + percpu_counter_add_batch( + &cache->space_info->total_bytes_pinned, + head->num_bytes, BTRFS_TOTAL_BYTES_PINNED_BATCH); + + btrfs_put_block_group(cache); + + btrfs_error_unpin_extent_range(fs_info, head->bytenr, + head->bytenr + head->num_bytes - 1); + } + btrfs_cleanup_ref_head_accounting(fs_info, delayed_refs, head); + btrfs_put_delayed_ref_head(head); + cond_resched(); + spin_lock(&delayed_refs->lock); + } + btrfs_qgroup_destroy_extent_records(trans); + + spin_unlock(&delayed_refs->lock); + + return ret; +} + +static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root) +{ + struct btrfs_inode *btrfs_inode; + struct list_head splice; + + INIT_LIST_HEAD(&splice); + + spin_lock(&root->delalloc_lock); + list_splice_init(&root->delalloc_inodes, &splice); + + while (!list_empty(&splice)) { + struct inode *inode = NULL; + btrfs_inode = list_first_entry(&splice, struct btrfs_inode, + delalloc_inodes); + __btrfs_del_delalloc_inode(root, btrfs_inode); + spin_unlock(&root->delalloc_lock); + + /* + * Make sure we get a live inode and that it'll not disappear + * meanwhile. + */ + inode = igrab(&btrfs_inode->vfs_inode); + if (inode) { + unsigned int nofs_flag; + + nofs_flag = memalloc_nofs_save(); + invalidate_inode_pages2(inode->i_mapping); + memalloc_nofs_restore(nofs_flag); + iput(inode); + } + spin_lock(&root->delalloc_lock); + } + spin_unlock(&root->delalloc_lock); +} + +static void btrfs_destroy_all_delalloc_inodes(struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *root; + struct list_head splice; + + INIT_LIST_HEAD(&splice); + + spin_lock(&fs_info->delalloc_root_lock); + list_splice_init(&fs_info->delalloc_roots, &splice); + while (!list_empty(&splice)) { + root = list_first_entry(&splice, struct btrfs_root, + delalloc_root); + root = btrfs_grab_root(root); + BUG_ON(!root); + spin_unlock(&fs_info->delalloc_root_lock); + + btrfs_destroy_delalloc_inodes(root); + btrfs_put_root(root); + + spin_lock(&fs_info->delalloc_root_lock); + } + spin_unlock(&fs_info->delalloc_root_lock); +} + +static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info, + struct extent_io_tree *dirty_pages, + int mark) +{ + int ret; + struct extent_buffer *eb; + u64 start = 0; + u64 end; + + while (1) { + ret = find_first_extent_bit(dirty_pages, start, &start, &end, + mark, NULL); + if (ret) + break; + + clear_extent_bits(dirty_pages, start, end, mark); + while (start <= end) { + eb = find_extent_buffer(fs_info, start); + start += fs_info->nodesize; + if (!eb) + continue; + wait_on_extent_buffer_writeback(eb); + + if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, + &eb->bflags)) + clear_extent_buffer_dirty(eb); + free_extent_buffer_stale(eb); + } + } + + return ret; +} + +static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info, + struct extent_io_tree *unpin) +{ + u64 start; + u64 end; + int ret; + + while (1) { + struct extent_state *cached_state = NULL; + + /* + * The btrfs_finish_extent_commit() may get the same range as + * ours between find_first_extent_bit and clear_extent_dirty. + * Hence, hold the unused_bg_unpin_mutex to avoid double unpin + * the same extent range. + */ + mutex_lock(&fs_info->unused_bg_unpin_mutex); + ret = find_first_extent_bit(unpin, 0, &start, &end, + EXTENT_DIRTY, &cached_state); + if (ret) { + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + break; + } + + clear_extent_dirty(unpin, start, end, &cached_state); + free_extent_state(cached_state); + btrfs_error_unpin_extent_range(fs_info, start, end); + mutex_unlock(&fs_info->unused_bg_unpin_mutex); + cond_resched(); + } + + return 0; +} + +static void btrfs_cleanup_bg_io(struct btrfs_block_group *cache) +{ + struct inode *inode; + + inode = cache->io_ctl.inode; + if (inode) { + unsigned int nofs_flag; + + nofs_flag = memalloc_nofs_save(); + invalidate_inode_pages2(inode->i_mapping); + memalloc_nofs_restore(nofs_flag); + + BTRFS_I(inode)->generation = 0; + cache->io_ctl.inode = NULL; + iput(inode); + } + ASSERT(cache->io_ctl.pages == NULL); + btrfs_put_block_group(cache); +} + +void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans, + struct btrfs_fs_info *fs_info) +{ + struct btrfs_block_group *cache; + + spin_lock(&cur_trans->dirty_bgs_lock); + while (!list_empty(&cur_trans->dirty_bgs)) { + cache = list_first_entry(&cur_trans->dirty_bgs, + struct btrfs_block_group, + dirty_list); + + if (!list_empty(&cache->io_list)) { + spin_unlock(&cur_trans->dirty_bgs_lock); + list_del_init(&cache->io_list); + btrfs_cleanup_bg_io(cache); + spin_lock(&cur_trans->dirty_bgs_lock); + } + + list_del_init(&cache->dirty_list); + spin_lock(&cache->lock); + cache->disk_cache_state = BTRFS_DC_ERROR; + spin_unlock(&cache->lock); + + spin_unlock(&cur_trans->dirty_bgs_lock); + btrfs_put_block_group(cache); + btrfs_delayed_refs_rsv_release(fs_info, 1); + spin_lock(&cur_trans->dirty_bgs_lock); + } + spin_unlock(&cur_trans->dirty_bgs_lock); + + /* + * Refer to the definition of io_bgs member for details why it's safe + * to use it without any locking + */ + while (!list_empty(&cur_trans->io_bgs)) { + cache = list_first_entry(&cur_trans->io_bgs, + struct btrfs_block_group, + io_list); + + list_del_init(&cache->io_list); + spin_lock(&cache->lock); + cache->disk_cache_state = BTRFS_DC_ERROR; + spin_unlock(&cache->lock); + btrfs_cleanup_bg_io(cache); + } +} + +void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans, + struct btrfs_fs_info *fs_info) +{ + struct btrfs_device *dev, *tmp; + + btrfs_cleanup_dirty_bgs(cur_trans, fs_info); + ASSERT(list_empty(&cur_trans->dirty_bgs)); + ASSERT(list_empty(&cur_trans->io_bgs)); + + list_for_each_entry_safe(dev, tmp, &cur_trans->dev_update_list, + post_commit_list) { + list_del_init(&dev->post_commit_list); + } + + btrfs_destroy_delayed_refs(cur_trans, fs_info); + + cur_trans->state = TRANS_STATE_COMMIT_START; + wake_up(&fs_info->transaction_blocked_wait); + + cur_trans->state = TRANS_STATE_UNBLOCKED; + wake_up(&fs_info->transaction_wait); + + btrfs_destroy_delayed_inodes(fs_info); + + btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages, + EXTENT_DIRTY); + btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents); + + cur_trans->state =TRANS_STATE_COMPLETED; + wake_up(&cur_trans->commit_wait); +} + +static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info) +{ + struct btrfs_transaction *t; + + mutex_lock(&fs_info->transaction_kthread_mutex); + + spin_lock(&fs_info->trans_lock); + while (!list_empty(&fs_info->trans_list)) { + t = list_first_entry(&fs_info->trans_list, + struct btrfs_transaction, list); + if (t->state >= TRANS_STATE_COMMIT_START) { + refcount_inc(&t->use_count); + spin_unlock(&fs_info->trans_lock); + btrfs_wait_for_commit(fs_info, t->transid); + btrfs_put_transaction(t); + spin_lock(&fs_info->trans_lock); + continue; + } + if (t == fs_info->running_transaction) { + t->state = TRANS_STATE_COMMIT_DOING; + spin_unlock(&fs_info->trans_lock); + /* + * We wait for 0 num_writers since we don't hold a trans + * handle open currently for this transaction. + */ + wait_event(t->writer_wait, + atomic_read(&t->num_writers) == 0); + } else { + spin_unlock(&fs_info->trans_lock); + } + btrfs_cleanup_one_transaction(t, fs_info); + + spin_lock(&fs_info->trans_lock); + if (t == fs_info->running_transaction) + fs_info->running_transaction = NULL; + list_del_init(&t->list); + spin_unlock(&fs_info->trans_lock); + + btrfs_put_transaction(t); + trace_btrfs_transaction_commit(fs_info->tree_root); + spin_lock(&fs_info->trans_lock); + } + spin_unlock(&fs_info->trans_lock); + btrfs_destroy_all_ordered_extents(fs_info); + btrfs_destroy_delayed_inodes(fs_info); + btrfs_assert_delayed_root_empty(fs_info); + btrfs_destroy_all_delalloc_inodes(fs_info); + btrfs_drop_all_logs(fs_info); + mutex_unlock(&fs_info->transaction_kthread_mutex); + + return 0; +} + +int btrfs_find_highest_objectid(struct btrfs_root *root, u64 *objectid) +{ + struct btrfs_path *path; + int ret; + struct extent_buffer *l; + struct btrfs_key search_key; + struct btrfs_key found_key; + int slot; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + search_key.objectid = BTRFS_LAST_FREE_OBJECTID; + search_key.type = -1; + search_key.offset = (u64)-1; + ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0); + if (ret < 0) + goto error; + BUG_ON(ret == 0); /* Corruption */ + if (path->slots[0] > 0) { + slot = path->slots[0] - 1; + l = path->nodes[0]; + btrfs_item_key_to_cpu(l, &found_key, slot); + *objectid = max_t(u64, found_key.objectid, + BTRFS_FIRST_FREE_OBJECTID - 1); + } else { + *objectid = BTRFS_FIRST_FREE_OBJECTID - 1; + } + ret = 0; +error: + btrfs_free_path(path); + return ret; +} + +int btrfs_find_free_objectid(struct btrfs_root *root, u64 *objectid) +{ + int ret; + mutex_lock(&root->objectid_mutex); + + if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) { + btrfs_warn(root->fs_info, + "the objectid of root %llu reaches its highest value", + root->root_key.objectid); + ret = -ENOSPC; + goto out; + } + + *objectid = ++root->highest_objectid; + ret = 0; +out: + mutex_unlock(&root->objectid_mutex); + return ret; +} |