1
linux/fs/btrfs/disk-io.c
Linus Torvalds a1b547f0f2 for-6.11-tag
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Merge tag 'for-6.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "The highlights are new logic behind background block group reclaim,
  automatic removal of qgroup after removing a subvolume and new
  'rescue=' mount options.

  The rest is optimizations, cleanups and refactoring.

  User visible features:

   - dynamic block group reclaim:
      - tunable framework to avoid situations where eager data
        allocations prevent creating new metadata chunks due to lack of
        unallocated space
      - reuse sysfs knob bg_reclaim_threshold (otherwise used only in
        zoned mode) for a fixed value threshold
      - new on/off sysfs knob "dynamic_reclaim" calculating the value
        based on heuristics, aiming to keep spare working space for
        relocating chunks but not to needlessly relocate partially
        utilized block groups or reclaim newly allocated ones
      - stats are exported in sysfs per block group type, files
        "reclaim_*"
      - this may increase IO load at unexpected times but the corner
        case of no allocatable block groups is known to be worse

   - automatically remove qgroup of deleted subvolumes:
      - adjust qgroup removal conditions, make sure all related
        subvolume data are already removed, or return EBUSY, also take
        into account setting of sysfs drop_subtree_threshold
      - also works in squota mode

   - mount option updates: new modes of 'rescue=' that allow to mount
     images (read-only) that could have been partially converted by user
     space tools
      - ignoremetacsums  - invalid metadata checksums are ignored
      - ignoresuperflags - super block flags that track conversion in
                           progress (like UUID or checksums)

  Core:

   - size of struct btrfs_inode is now below 1024 (on a release config),
     improved memory packing and other secondary effects

   - switch tracking of open inodes from rb-tree to xarray, minor
     performance improvement

   - reduce number of empty transaction commits when there are no dirty
     data/metadata

   - memory allocation optimizations (reduced numbers, reordering out of
     critical sections)

   - extent map structure optimizations and refactoring, more sanity
     checks

   - more subpage in zoned mode preparations or fixes

   - general snapshot code cleanups, improvements and documentation

   - tree-checker updates: more file extent ram_bytes fixes, continued

   - raid-stripe-tree update (not backward compatible):
      - remove extent encoding field from the structure, can be inferred
        from other information
      - requires btrfs-progs 6.9.1 or newer

   - cleanups and refactoring
      - error message updates
      - error handling improvements
      - return type and parameter cleanups and improvements"

* tag 'for-6.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (152 commits)
  btrfs: fix extent map use-after-free when adding pages to compressed bio
  btrfs: fix bitmap leak when loading free space cache on duplicate entry
  btrfs: remove the BUG_ON() inside extent_range_clear_dirty_for_io()
  btrfs: move extent_range_clear_dirty_for_io() into inode.c
  btrfs: enhance compression error messages
  btrfs: fix data race when accessing the last_trans field of a root
  btrfs: rename the extra_gfp parameter of btrfs_alloc_page_array()
  btrfs: remove the extra_gfp parameter from btrfs_alloc_folio_array()
  btrfs: introduce new "rescue=ignoresuperflags" mount option
  btrfs: introduce new "rescue=ignoremetacsums" mount option
  btrfs: output the unrecognized super block flags as hex
  btrfs: remove unused Opt enums
  btrfs: tree-checker: add extra ram_bytes and disk_num_bytes check
  btrfs: fix the ram_bytes assignment for truncated ordered extents
  btrfs: make validate_extent_map() catch ram_bytes mismatch
  btrfs: ignore incorrect btrfs_file_extent_item::ram_bytes
  btrfs: cleanup the bytenr usage inside btrfs_extent_item_to_extent_map()
  btrfs: fix typo in error message in btrfs_validate_super()
  btrfs: move the direct IO code into its own file
  btrfs: pass a btrfs_inode to btrfs_set_prop()
  ...
2024-07-17 12:38:04 -07:00

4952 lines
139 KiB
C

// 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 "bio.h"
#include "print-tree.h"
#include "locking.h"
#include "tree-log.h"
#include "free-space-cache.h"
#include "free-space-tree.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"
#include "zoned.h"
#include "subpage.h"
#include "fs.h"
#include "accessors.h"
#include "extent-tree.h"
#include "root-tree.h"
#include "defrag.h"
#include "uuid-tree.h"
#include "relocation.h"
#include "scrub.h"
#include "super.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 int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
{
if (fs_info->csum_shash)
crypto_free_shash(fs_info->csum_shash);
}
/*
* 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;
int num_pages;
u32 first_page_part;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
char *kaddr;
int i;
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
if (buf->addr) {
/* Pages are contiguous, handle them as a big one. */
kaddr = buf->addr;
first_page_part = fs_info->nodesize;
num_pages = 1;
} else {
kaddr = folio_address(buf->folios[0]);
first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
num_pages = num_extent_pages(buf);
}
crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
first_page_part - BTRFS_CSUM_SIZE);
/*
* Multiple single-page folios case would reach here.
*
* nodesize <= PAGE_SIZE and large folio all handled by above
* crypto_shash_update() already.
*/
for (i = 1; i < num_pages && INLINE_EXTENT_BUFFER_PAGES > 1; i++) {
kaddr = folio_address(buf->folios[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.
*/
int btrfs_buffer_uptodate(struct extent_buffer *eb, u64 parent_transid, int atomic)
{
if (!extent_buffer_uptodate(eb))
return 0;
if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
return 1;
if (atomic)
return -EAGAIN;
if (!extent_buffer_uptodate(eb) ||
btrfs_header_generation(eb) != parent_transid) {
btrfs_err_rl(eb->fs_info,
"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
eb->start, eb->read_mirror,
parent_transid, btrfs_header_generation(eb));
clear_extent_buffer_uptodate(eb);
return 0;
}
return 1;
}
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.
*/
int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
const struct btrfs_super_block *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, (const u8 *)disk_sb + BTRFS_CSUM_SIZE,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
if (memcmp(disk_sb->csum, result, fs_info->csum_size))
return 1;
return 0;
}
static int btrfs_repair_eb_io_failure(const struct extent_buffer *eb,
int mirror_num)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
int num_folios = num_extent_folios(eb);
int ret = 0;
if (sb_rdonly(fs_info->sb))
return -EROFS;
for (int i = 0; i < num_folios; i++) {
struct folio *folio = eb->folios[i];
u64 start = max_t(u64, eb->start, folio_pos(folio));
u64 end = min_t(u64, eb->start + eb->len,
folio_pos(folio) + eb->folio_size);
u32 len = end - start;
ret = btrfs_repair_io_failure(fs_info, 0, start, len,
start, folio, offset_in_folio(folio, start),
mirror_num);
if (ret)
break;
}
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.
*
* @check: expected tree parentness check, see the comments of the
* structure for details.
*/
int btrfs_read_extent_buffer(struct extent_buffer *eb,
const struct btrfs_tree_parent_check *check)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
int failed = 0;
int ret;
int num_copies = 0;
int mirror_num = 0;
int failed_mirror = 0;
ASSERT(check);
while (1) {
clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num, check);
if (!ret)
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.
*/
blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio)
{
struct extent_buffer *eb = bbio->private;
struct btrfs_fs_info *fs_info = eb->fs_info;
u64 found_start = btrfs_header_bytenr(eb);
u64 last_trans;
u8 result[BTRFS_CSUM_SIZE];
int ret;
/* Btree blocks are always contiguous on disk. */
if (WARN_ON_ONCE(bbio->file_offset != eb->start))
return BLK_STS_IOERR;
if (WARN_ON_ONCE(bbio->bio.bi_iter.bi_size != eb->len))
return BLK_STS_IOERR;
/*
* If an extent_buffer is marked as EXTENT_BUFFER_ZONED_ZEROOUT, don't
* checksum it but zero-out its content. This is done to preserve
* ordering of I/O without unnecessarily writing out data.
*/
if (test_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags)) {
memzero_extent_buffer(eb, 0, eb->len);
return BLK_STS_OK;
}
if (WARN_ON_ONCE(found_start != eb->start))
return BLK_STS_IOERR;
if (WARN_ON(!btrfs_folio_test_uptodate(fs_info, eb->folios[0],
eb->start, eb->len)))
return BLK_STS_IOERR;
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(eb);
if (ret < 0)
goto error;
/*
* Also check the generation, the eb reached here must be newer than
* last committed. Or something seriously wrong happened.
*/
last_trans = btrfs_get_last_trans_committed(fs_info);
if (unlikely(btrfs_header_generation(eb) <= last_trans)) {
ret = -EUCLEAN;
btrfs_err(fs_info,
"block=%llu bad generation, have %llu expect > %llu",
eb->start, btrfs_header_generation(eb), last_trans);
goto error;
}
write_extent_buffer(eb, result, 0, fs_info->csum_size);
return BLK_STS_OK;
error:
btrfs_print_tree(eb, 0);
btrfs_err(fs_info, "block=%llu write time tree block corruption detected",
eb->start);
/*
* Be noisy if this is an extent buffer from a log tree. We don't abort
* a transaction in case there's a bad log tree extent buffer, we just
* fallback to a transaction commit. Still we want to know when there is
* a bad log tree extent buffer, as that may signal a bug somewhere.
*/
WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG) ||
btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID);
return errno_to_blk_status(ret);
}
static bool 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];
read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
BTRFS_FSID_SIZE);
/*
* alloc_fsid_devices() copies the fsid into fs_devices::metadata_uuid.
* This is then overwritten by metadata_uuid if it is present in the
* device_list_add(). The same true for a seed device as well. So use of
* fs_devices::metadata_uuid is appropriate here.
*/
if (memcmp(fsid, fs_info->fs_devices->metadata_uuid, BTRFS_FSID_SIZE) == 0)
return false;
list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
return false;
return true;
}
/* Do basic extent buffer checks at read time */
int btrfs_validate_extent_buffer(struct extent_buffer *eb,
const struct btrfs_tree_parent_check *check)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
u64 found_start;
const u32 csum_size = fs_info->csum_size;
u8 found_level;
u8 result[BTRFS_CSUM_SIZE];
const u8 *header_csum;
int ret = 0;
const bool ignore_csum = btrfs_test_opt(fs_info, IGNOREMETACSUMS);
ASSERT(check);
found_start = btrfs_header_bytenr(eb);
if (found_start != eb->start) {
btrfs_err_rl(fs_info,
"bad tree block start, mirror %u want %llu have %llu",
eb->read_mirror, eb->start, found_start);
ret = -EIO;
goto out;
}
if (check_tree_block_fsid(eb)) {
btrfs_err_rl(fs_info, "bad fsid on logical %llu mirror %u",
eb->start, eb->read_mirror);
ret = -EIO;
goto out;
}
found_level = btrfs_header_level(eb);
if (found_level >= BTRFS_MAX_LEVEL) {
btrfs_err(fs_info,
"bad tree block level, mirror %u level %d on logical %llu",
eb->read_mirror, btrfs_header_level(eb), eb->start);
ret = -EIO;
goto out;
}
csum_tree_block(eb, result);
header_csum = folio_address(eb->folios[0]) +
get_eb_offset_in_folio(eb, offsetof(struct btrfs_header, csum));
if (memcmp(result, header_csum, csum_size) != 0) {
btrfs_warn_rl(fs_info,
"checksum verify failed on logical %llu mirror %u wanted " CSUM_FMT " found " CSUM_FMT " level %d%s",
eb->start, eb->read_mirror,
CSUM_FMT_VALUE(csum_size, header_csum),
CSUM_FMT_VALUE(csum_size, result),
btrfs_header_level(eb),
ignore_csum ? ", ignored" : "");
if (!ignore_csum) {
ret = -EUCLEAN;
goto out;
}
}
if (found_level != check->level) {
btrfs_err(fs_info,
"level verify failed on logical %llu mirror %u wanted %u found %u",
eb->start, eb->read_mirror, check->level, found_level);
ret = -EIO;
goto out;
}
if (unlikely(check->transid &&
btrfs_header_generation(eb) != check->transid)) {
btrfs_err_rl(eb->fs_info,
"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
eb->start, eb->read_mirror, check->transid,
btrfs_header_generation(eb));
ret = -EIO;
goto out;
}
if (check->has_first_key) {
const struct btrfs_key *expect_key = &check->first_key;
struct btrfs_key found_key;
if (found_level)
btrfs_node_key_to_cpu(eb, &found_key, 0);
else
btrfs_item_key_to_cpu(eb, &found_key, 0);
if (unlikely(btrfs_comp_cpu_keys(expect_key, &found_key))) {
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, check->transid,
expect_key->objectid,
expect_key->type, expect_key->offset,
found_key.objectid, found_key.type,
found_key.offset);
ret = -EUCLEAN;
goto out;
}
}
if (check->owner_root) {
ret = btrfs_check_eb_owner(eb, check->owner_root);
if (ret < 0)
goto out;
}
/*
* 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(eb)) {
set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
ret = -EIO;
}
if (found_level > 0 && btrfs_check_node(eb))
ret = -EIO;
if (ret)
btrfs_err(fs_info,
"read time tree block corruption detected on logical %llu mirror %u",
eb->start, eb->read_mirror);
out:
return ret;
}
#ifdef CONFIG_MIGRATION
static int btree_migrate_folio(struct address_space *mapping,
struct folio *dst, struct folio *src, enum migrate_mode mode)
{
/*
* we can't safely write a btree page from here,
* we haven't done the locking hook
*/
if (folio_test_dirty(src))
return -EAGAIN;
/*
* Buffers may be managed in a filesystem specific way.
* We must have no buffers or drop them.
*/
if (folio_get_private(src) &&
!filemap_release_folio(src, GFP_KERNEL))
return -EAGAIN;
return migrate_folio(mapping, dst, src, mode);
}
#else
#define btree_migrate_folio NULL
#endif
static int btree_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
int ret;
if (wbc->sync_mode == WB_SYNC_NONE) {
struct btrfs_fs_info *fs_info;
if (wbc->for_kupdate)
return 0;
fs_info = inode_to_fs_info(mapping->host);
/* 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 bool btree_release_folio(struct folio *folio, gfp_t gfp_flags)
{
if (folio_test_writeback(folio) || folio_test_dirty(folio))
return false;
return try_release_extent_buffer(&folio->page);
}
static void btree_invalidate_folio(struct folio *folio, size_t offset,
size_t length)
{
struct extent_io_tree *tree;
tree = &folio_to_inode(folio)->io_tree;
extent_invalidate_folio(tree, folio, offset);
btree_release_folio(folio, GFP_NOFS);
if (folio_get_private(folio)) {
btrfs_warn(folio_to_fs_info(folio),
"folio private not zero on folio %llu",
(unsigned long long)folio_pos(folio));
folio_detach_private(folio);
}
}
#ifdef DEBUG
static bool btree_dirty_folio(struct address_space *mapping,
struct folio *folio)
{
struct btrfs_fs_info *fs_info = inode_to_fs_info(mapping->host);
struct btrfs_subpage_info *spi = fs_info->subpage_info;
struct btrfs_subpage *subpage;
struct extent_buffer *eb;
int cur_bit = 0;
u64 page_start = folio_pos(folio);
if (fs_info->sectorsize == PAGE_SIZE) {
eb = folio_get_private(folio);
BUG_ON(!eb);
BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
BUG_ON(!atomic_read(&eb->refs));
btrfs_assert_tree_write_locked(eb);
return filemap_dirty_folio(mapping, folio);
}
ASSERT(spi);
subpage = folio_get_private(folio);
for (cur_bit = spi->dirty_offset;
cur_bit < spi->dirty_offset + spi->bitmap_nr_bits;
cur_bit++) {
unsigned long flags;
u64 cur;
spin_lock_irqsave(&subpage->lock, flags);
if (!test_bit(cur_bit, subpage->bitmaps)) {
spin_unlock_irqrestore(&subpage->lock, flags);
continue;
}
spin_unlock_irqrestore(&subpage->lock, flags);
cur = page_start + cur_bit * fs_info->sectorsize;
eb = find_extent_buffer(fs_info, cur);
ASSERT(eb);
ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
ASSERT(atomic_read(&eb->refs));
btrfs_assert_tree_write_locked(eb);
free_extent_buffer(eb);
cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits) - 1;
}
return filemap_dirty_folio(mapping, folio);
}
#else
#define btree_dirty_folio filemap_dirty_folio
#endif
static const struct address_space_operations btree_aops = {
.writepages = btree_writepages,
.release_folio = btree_release_folio,
.invalidate_folio = btree_invalidate_folio,
.migrate_folio = btree_migrate_folio,
.dirty_folio = btree_dirty_folio,
};
struct extent_buffer *btrfs_find_create_tree_block(
struct btrfs_fs_info *fs_info,
u64 bytenr, u64 owner_root,
int level)
{
if (btrfs_is_testing(fs_info))
return alloc_test_extent_buffer(fs_info, bytenr);
return alloc_extent_buffer(fs_info, bytenr, owner_root, level);
}
/*
* Read tree block at logical address @bytenr and do variant basic but critical
* verification.
*
* @check: expected tree parentness check, see comments of the
* structure for details.
*/
struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
struct btrfs_tree_parent_check *check)
{
struct extent_buffer *buf = NULL;
int ret;
ASSERT(check);
buf = btrfs_find_create_tree_block(fs_info, bytenr, check->owner_root,
check->level);
if (IS_ERR(buf))
return buf;
ret = btrfs_read_extent_buffer(buf, check);
if (ret) {
free_extent_buffer_stale(buf);
return ERR_PTR(ret);
}
return buf;
}
static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
u64 objectid)
{
bool dummy = btrfs_is_testing(fs_info);
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->fs_info = fs_info;
root->root_key.objectid = objectid;
root->node = NULL;
root->commit_root = NULL;
root->state = 0;
RB_CLEAR_NODE(&root->rb_node);
btrfs_set_root_last_trans(root, 0);
root->free_objectid = 0;
root->nr_delalloc_inodes = 0;
root->nr_ordered_extents = 0;
xa_init(&root->inodes);
xa_init(&root->delayed_nodes);
btrfs_init_root_block_rsv(root);
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);
spin_lock_init(&root->delalloc_lock);
spin_lock_init(&root->ordered_extent_lock);
spin_lock_init(&root->accounting_lock);
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);
btrfs_set_root_log_transid(root, 0);
root->log_transid_committed = -1;
btrfs_set_root_last_log_commit(root, 0);
root->anon_dev = 0;
if (!dummy) {
extent_io_tree_init(fs_info, &root->dirty_log_pages,
IO_TREE_ROOT_DIRTY_LOG_PAGES);
extent_io_tree_init(fs_info, &root->log_csum_range,
IO_TREE_LOG_CSUM_RANGE);
}
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
static int global_root_cmp(struct rb_node *a_node, const struct rb_node *b_node)
{
const struct btrfs_root *a = rb_entry(a_node, struct btrfs_root, rb_node);
const struct btrfs_root *b = rb_entry(b_node, struct btrfs_root, rb_node);
return btrfs_comp_cpu_keys(&a->root_key, &b->root_key);
}
static int global_root_key_cmp(const void *k, const struct rb_node *node)
{
const struct btrfs_key *key = k;
const struct btrfs_root *root = rb_entry(node, struct btrfs_root, rb_node);
return btrfs_comp_cpu_keys(key, &root->root_key);
}
int btrfs_global_root_insert(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct rb_node *tmp;
int ret = 0;
write_lock(&fs_info->global_root_lock);
tmp = rb_find_add(&root->rb_node, &fs_info->global_root_tree, global_root_cmp);
write_unlock(&fs_info->global_root_lock);
if (tmp) {
ret = -EEXIST;
btrfs_warn(fs_info, "global root %llu %llu already exists",
btrfs_root_id(root), root->root_key.offset);
}
return ret;
}
void btrfs_global_root_delete(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
write_lock(&fs_info->global_root_lock);
rb_erase(&root->rb_node, &fs_info->global_root_tree);
write_unlock(&fs_info->global_root_lock);
}
struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
struct btrfs_key *key)
{
struct rb_node *node;
struct btrfs_root *root = NULL;
read_lock(&fs_info->global_root_lock);
node = rb_find(key, &fs_info->global_root_tree, global_root_key_cmp);
if (node)
root = container_of(node, struct btrfs_root, rb_node);
read_unlock(&fs_info->global_root_lock);
return root;
}
static u64 btrfs_global_root_id(struct btrfs_fs_info *fs_info, u64 bytenr)
{
struct btrfs_block_group *block_group;
u64 ret;
if (!btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
return 0;
if (bytenr)
block_group = btrfs_lookup_block_group(fs_info, bytenr);
else
block_group = btrfs_lookup_first_block_group(fs_info, bytenr);
ASSERT(block_group);
if (!block_group)
return 0;
ret = block_group->global_root_id;
btrfs_put_block_group(block_group);
return ret;
}
struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr)
{
struct btrfs_key key = {
.objectid = BTRFS_CSUM_TREE_OBJECTID,
.type = BTRFS_ROOT_ITEM_KEY,
.offset = btrfs_global_root_id(fs_info, bytenr),
};
return btrfs_global_root(fs_info, &key);
}
struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
{
struct btrfs_key key = {
.objectid = BTRFS_EXTENT_TREE_OBJECTID,
.type = BTRFS_ROOT_ITEM_KEY,
.offset = btrfs_global_root_id(fs_info, bytenr),
};
return btrfs_global_root(fs_info, &key);
}
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,
0, BTRFS_NESTING_NORMAL);
if (IS_ERR(leaf)) {
ret = PTR_ERR(leaf);
leaf = NULL;
goto fail;
}
root->node = leaf;
btrfs_mark_buffer_dirty(trans, leaf);
root->commit_root = btrfs_root_node(root);
set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
btrfs_set_root_flags(&root->root_item, 0);
btrfs_set_root_limit(&root->root_item, 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);
btrfs_set_root_drop_level(&root->root_item, 0);
btrfs_tree_unlock(leaf);
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;
return root;
fail:
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;
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;
return root;
}
int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct extent_buffer *leaf;
/*
* 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, 0, BTRFS_NESTING_NORMAL);
if (IS_ERR(leaf))
return PTR_ERR(leaf);
root->node = leaf;
btrfs_mark_buffer_dirty(trans, root->node);
btrfs_tree_unlock(root->node);
return 0;
}
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);
if (!btrfs_is_zoned(fs_info)) {
int ret = btrfs_alloc_log_tree_node(trans, log_root);
if (ret) {
btrfs_put_root(log_root);
return ret;
}
}
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;
int ret;
log_root = alloc_log_tree(trans, fs_info);
if (IS_ERR(log_root))
return PTR_ERR(log_root);
ret = btrfs_alloc_log_tree_node(trans, log_root);
if (ret) {
btrfs_put_root(log_root);
return ret;
}
btrfs_set_root_last_trans(log_root, trans->transid);
log_root->root_key.offset = btrfs_root_id(root);
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;
btrfs_set_root_log_transid(root, 0);
root->log_transid_committed = -1;
btrfs_set_root_last_log_commit(root, 0);
return 0;
}
static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
struct btrfs_path *path,
const struct btrfs_key *key)
{
struct btrfs_root *root;
struct btrfs_tree_parent_check check = { 0 };
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);
check.level = level;
check.transid = generation;
check.owner_root = key->objectid;
root->node = read_tree_block(fs_info, btrfs_root_bytenr(&root->root_item),
&check);
if (IS_ERR(root->node)) {
ret = PTR_ERR(root->node);
root->node = NULL;
goto fail;
}
if (!btrfs_buffer_uptodate(root->node, generation, 0)) {
ret = -EIO;
goto fail;
}
/*
* For real fs, and not log/reloc trees, root owner must
* match its root node owner
*/
if (!btrfs_is_testing(fs_info) &&
btrfs_root_id(root) != BTRFS_TREE_LOG_OBJECTID &&
btrfs_root_id(root) != BTRFS_TREE_RELOC_OBJECTID &&
btrfs_root_id(root) != btrfs_header_owner(root->node)) {
btrfs_crit(fs_info,
"root=%llu block=%llu, tree root owner mismatch, have %llu expect %llu",
btrfs_root_id(root), root->node->start,
btrfs_header_owner(root->node),
btrfs_root_id(root));
ret = -EUCLEAN;
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,
const 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;
btrfs_drew_lock_init(&root->snapshot_lock);
if (btrfs_root_id(root) != BTRFS_TREE_LOG_OBJECTID &&
!btrfs_is_data_reloc_root(root) &&
is_fstree(btrfs_root_id(root))) {
set_bit(BTRFS_ROOT_SHAREABLE, &root->state);
btrfs_check_and_init_root_item(&root->root_item);
}
/*
* Don't assign anonymous block device to roots that are not exposed to
* userspace, the id pool is limited to 1M
*/
if (is_fstree(btrfs_root_id(root)) &&
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_init_root_free_objectid(root);
if (ret) {
mutex_unlock(&root->objectid_mutex);
goto fail;
}
ASSERT(root->free_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);
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)
{
struct btrfs_key key = {
.objectid = objectid,
.type = BTRFS_ROOT_ITEM_KEY,
.offset = 0,
};
switch (objectid) {
case BTRFS_ROOT_TREE_OBJECTID:
return btrfs_grab_root(fs_info->tree_root);
case BTRFS_EXTENT_TREE_OBJECTID:
return btrfs_grab_root(btrfs_global_root(fs_info, &key));
case BTRFS_CHUNK_TREE_OBJECTID:
return btrfs_grab_root(fs_info->chunk_root);
case BTRFS_DEV_TREE_OBJECTID:
return btrfs_grab_root(fs_info->dev_root);
case BTRFS_CSUM_TREE_OBJECTID:
return btrfs_grab_root(btrfs_global_root(fs_info, &key));
case BTRFS_QUOTA_TREE_OBJECTID:
return btrfs_grab_root(fs_info->quota_root);
case BTRFS_UUID_TREE_OBJECTID:
return btrfs_grab_root(fs_info->uuid_root);
case BTRFS_BLOCK_GROUP_TREE_OBJECTID:
return btrfs_grab_root(fs_info->block_group_root);
case BTRFS_FREE_SPACE_TREE_OBJECTID:
return btrfs_grab_root(btrfs_global_root(fs_info, &key));
case BTRFS_RAID_STRIPE_TREE_OBJECTID:
return btrfs_grab_root(fs_info->stripe_root);
default:
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)btrfs_root_id(root),
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(const 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));
WARN_ON_ONCE(1);
while (refcount_read(&root->refs) > 1)
btrfs_put_root(root);
btrfs_put_root(root);
}
#endif
}
static void free_global_roots(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root;
struct rb_node *node;
while ((node = rb_first_postorder(&fs_info->global_root_tree)) != NULL) {
root = rb_entry(node, struct btrfs_root, rb_node);
rb_erase(&root->rb_node, &fs_info->global_root_tree);
btrfs_put_root(root);
}
}
void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
{
struct percpu_counter *em_counter = &fs_info->evictable_extent_maps;
percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
percpu_counter_destroy(&fs_info->delalloc_bytes);
percpu_counter_destroy(&fs_info->ordered_bytes);
if (percpu_counter_initialized(em_counter))
ASSERT(percpu_counter_sum_positive(em_counter) == 0);
percpu_counter_destroy(em_counter);
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);
free_global_roots(fs_info);
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->quota_root);
btrfs_put_root(fs_info->uuid_root);
btrfs_put_root(fs_info->fs_root);
btrfs_put_root(fs_info->data_reloc_root);
btrfs_put_root(fs_info->block_group_root);
btrfs_put_root(fs_info->stripe_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);
kfree(fs_info->subpage_info);
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 NULL for a 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;
/*
* If we're called for non-subvolume trees, and above function didn't
* find one, do not try to read it from disk.
*
* This is namely for free-space-tree and quota tree, which can change
* at runtime and should only be grabbed from fs_info.
*/
if (!is_fstree(objectid) && objectid != BTRFS_DATA_RELOC_TREE_OBJECTID)
return ERR_PTR(-ENOENT);
again:
root = btrfs_lookup_fs_root(fs_info, objectid);
if (root) {
/*
* Some other caller may have read out the newly inserted
* subvolume already (for things like backref walk etc). Not
* that common but still possible. In that case, we just need
* to free the anon_dev.
*/
if (unlikely(anon_dev && *anon_dev)) {
free_anon_bdev(*anon_dev);
*anon_dev = 0;
}
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 ? *anon_dev : 0);
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
* responsibility 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 && *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, NULL, 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 NULL, allocate a new anonymous block device or use the
* parameter value if not NULL
*/
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);
}
/*
* 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;
}
static int cleaner_kthread(void *arg)
{
struct btrfs_fs_info *fs_info = arg;
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;
}
if (test_and_clear_bit(BTRFS_FS_FEATURE_CHANGED, &fs_info->flags))
btrfs_sysfs_feature_update(fs_info);
btrfs_run_delayed_iputs(fs_info);
again = btrfs_clean_one_deleted_snapshot(fs_info);
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->reclaim_bgs_lock to avoid racing
* with relocation (btrfs_relocate_chunk) and relocation
* acquires fs_info->cleaner_mutex (btrfs_relocate_block_group)
* after acquiring fs_info->reclaim_bgs_lock. So we
* can't hold, nor need to, fs_info->cleaner_mutex when deleting
* unused block groups.
*/
btrfs_delete_unused_bgs(fs_info);
/*
* Reclaim block groups in the reclaim_bgs list after we deleted
* all unused block_groups. This possibly gives us some more free
* space.
*/
btrfs_reclaim_bgs(fs_info);
sleep:
clear_and_wake_up_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 delta;
unsigned long delay;
bool cannot_commit;
do {
cannot_commit = false;
delay = msecs_to_jiffies(fs_info->commit_interval * 1000);
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;
}
delta = ktime_get_seconds() - cur->start_time;
if (!test_and_clear_bit(BTRFS_FS_COMMIT_TRANS, &fs_info->flags) &&
cur->state < TRANS_STATE_COMMIT_PREP &&
delta < fs_info->commit_interval) {
spin_unlock(&fs_info->trans_lock);
delay -= msecs_to_jiffies((delta - 1) * 1000);
delay = min(delay,
msecs_to_jiffies(fs_info->commit_interval * 1000));
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 (BTRFS_FS_ERROR(fs_info))
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));
if (!btrfs_fs_compat_ro(info, BLOCK_GROUP_TREE)) {
struct btrfs_root *extent_root = btrfs_extent_root(info, 0);
struct btrfs_root *csum_root = btrfs_csum_root(info, 0);
btrfs_set_backup_extent_root(root_backup,
extent_root->node->start);
btrfs_set_backup_extent_root_gen(root_backup,
btrfs_header_generation(extent_root->node));
btrfs_set_backup_extent_root_level(root_backup,
btrfs_header_level(extent_root->node));
btrfs_set_backup_csum_root(root_backup, csum_root->node->start);
btrfs_set_backup_csum_root_gen(root_backup,
btrfs_header_generation(csum_root->node));
btrfs_set_backup_csum_root_level(root_backup,
btrfs_header_level(csum_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_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);
}
/*
* 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);
if (fs_info->endio_workers)
destroy_workqueue(fs_info->endio_workers);
if (fs_info->rmw_workers)
destroy_workqueue(fs_info->rmw_workers);
if (fs_info->compressed_write_workers)
destroy_workqueue(fs_info->compressed_write_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->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.
*/
if (fs_info->endio_meta_workers)
destroy_workqueue(fs_info->endio_meta_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;
}
}
static void free_global_root_pointers(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root, *tmp;
rbtree_postorder_for_each_entry_safe(root, tmp,
&fs_info->global_root_tree,
rb_node)
free_root_extent_buffers(root);
}
/* 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_global_root_pointers(info);
free_root_extent_buffers(info->dev_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);
free_root_extent_buffers(info->block_group_root);
free_root_extent_buffers(info->stripe_root);
if (free_chunk_root)
free_root_extent_buffers(info->chunk_root);
}
void btrfs_put_root(struct btrfs_root *root)
{
if (!root)
return;
if (refcount_dec_and_test(&root->refs)) {
if (WARN_ON(!xa_empty(&root->inodes)))
xa_destroy(&root->inodes);
WARN_ON(test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state));
if (root->anon_dev)
free_anon_bdev(root->anon_dev);
free_root_extent_buffers(root);
#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);
atomic_set(&fs_info->reloc_cancel_req, 0);
}
static int btrfs_init_btree_inode(struct super_block *sb)
{
struct btrfs_fs_info *fs_info = btrfs_sb(sb);
unsigned long hash = btrfs_inode_hash(BTRFS_BTREE_INODE_OBJECTID,
fs_info->tree_root);
struct inode *inode;
inode = new_inode(sb);
if (!inode)
return -ENOMEM;
btrfs_set_inode_number(BTRFS_I(inode), 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;
mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
IO_TREE_BTREE_INODE_IO);
extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
BTRFS_I(inode)->root = btrfs_grab_root(fs_info->tree_root);
set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
__insert_inode_hash(inode, hash);
fs_info->btree_inode = inode;
return 0;
}
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;
fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
mutex_init(&fs_info->qgroup_rescan_lock);
}
static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info)
{
u32 max_active = fs_info->thread_pool_size;
unsigned int flags = WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND;
unsigned int ordered_flags = WQ_MEM_RECLAIM | WQ_FREEZABLE;
fs_info->workers =
btrfs_alloc_workqueue(fs_info, "worker", flags, 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_ordered_workqueue(fs_info, "fixup", ordered_flags);
fs_info->endio_workers =
alloc_workqueue("btrfs-endio", flags, max_active);
fs_info->endio_meta_workers =
alloc_workqueue("btrfs-endio-meta", flags, max_active);
fs_info->rmw_workers = alloc_workqueue("btrfs-rmw", flags, max_active);
fs_info->endio_write_workers =
btrfs_alloc_workqueue(fs_info, "endio-write", flags,
max_active, 2);
fs_info->compressed_write_workers =
alloc_workqueue("btrfs-compressed-write", flags, max_active);
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->qgroup_rescan_workers =
btrfs_alloc_ordered_workqueue(fs_info, "qgroup-rescan",
ordered_flags);
fs_info->discard_ctl.discard_workers =
alloc_ordered_workqueue("btrfs_discard", WQ_FREEZABLE);
if (!(fs_info->workers &&
fs_info->delalloc_workers && fs_info->flush_workers &&
fs_info->endio_workers && fs_info->endio_meta_workers &&
fs_info->compressed_write_workers &&
fs_info->endio_write_workers &&
fs_info->endio_freespace_worker && fs_info->rmw_workers &&
fs_info->caching_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_tree_parent_check check = { 0 };
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;
check.level = level;
check.transid = fs_info->generation + 1;
check.owner_root = BTRFS_TREE_LOG_OBJECTID;
log_tree_root->node = read_tree_block(fs_info, bytenr, &check);
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;
}
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 load_global_roots_objectid(struct btrfs_root *tree_root,
struct btrfs_path *path, u64 objectid,
const char *name)
{
struct btrfs_fs_info *fs_info = tree_root->fs_info;
struct btrfs_root *root;
u64 max_global_id = 0;
int ret;
struct btrfs_key key = {
.objectid = objectid,
.type = BTRFS_ROOT_ITEM_KEY,
.offset = 0,
};
bool found = false;
/* If we have IGNOREDATACSUMS skip loading these roots. */
if (objectid == BTRFS_CSUM_TREE_OBJECTID &&
btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
set_bit(BTRFS_FS_STATE_NO_DATA_CSUMS, &fs_info->fs_state);
return 0;
}
while (1) {
ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
if (ret < 0)
break;
if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_leaf(tree_root, path);
if (ret) {
if (ret > 0)
ret = 0;
break;
}
}
ret = 0;
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if (key.objectid != objectid)
break;
btrfs_release_path(path);
/*
* Just worry about this for extent tree, it'll be the same for
* everybody.
*/
if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
max_global_id = max(max_global_id, key.offset);
found = true;
root = read_tree_root_path(tree_root, path, &key);
if (IS_ERR(root)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
ret = PTR_ERR(root);
break;
}
set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
ret = btrfs_global_root_insert(root);
if (ret) {
btrfs_put_root(root);
break;
}
key.offset++;
}
btrfs_release_path(path);
if (objectid == BTRFS_EXTENT_TREE_OBJECTID)
fs_info->nr_global_roots = max_global_id + 1;
if (!found || ret) {
if (objectid == BTRFS_CSUM_TREE_OBJECTID)
set_bit(BTRFS_FS_STATE_NO_DATA_CSUMS, &fs_info->fs_state);
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS))
ret = ret ? ret : -ENOENT;
else
ret = 0;
btrfs_err(fs_info, "failed to load root %s", name);
}
return ret;
}
static int load_global_roots(struct btrfs_root *tree_root)
{
struct btrfs_path *path;
int ret = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = load_global_roots_objectid(tree_root, path,
BTRFS_EXTENT_TREE_OBJECTID, "extent");
if (ret)
goto out;
ret = load_global_roots_objectid(tree_root, path,
BTRFS_CSUM_TREE_OBJECTID, "csum");
if (ret)
goto out;
if (!btrfs_fs_compat_ro(tree_root->fs_info, FREE_SPACE_TREE))
goto out;
ret = load_global_roots_objectid(tree_root, path,
BTRFS_FREE_SPACE_TREE_OBJECTID,
"free space");
out:
btrfs_free_path(path);
return ret;
}
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;
ASSERT(fs_info->tree_root);
ret = load_global_roots(tree_root);
if (ret)
return ret;
location.type = BTRFS_ROOT_ITEM_KEY;
location.offset = 0;
if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE)) {
location.objectid = BTRFS_BLOCK_GROUP_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
ret = PTR_ERR(root);
goto out;
}
} else {
set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
fs_info->block_group_root = root;
}
}
location.objectid = BTRFS_DEV_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
ret = PTR_ERR(root);
goto out;
}
} else {
set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
fs_info->dev_root = root;
}
/* Initialize fs_info for all devices in any case */
ret = btrfs_init_devices_late(fs_info);
if (ret)
goto out;
/*
* 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)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
ret = PTR_ERR(root);
goto out;
}
} else {
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);
fs_info->quota_root = root;
}
location.objectid = BTRFS_UUID_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
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_incompat(fs_info, RAID_STRIPE_TREE)) {
location.objectid = BTRFS_RAID_STRIPE_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
ret = PTR_ERR(root);
goto out;
}
} else {
set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
fs_info->stripe_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
*/
int btrfs_validate_super(const struct btrfs_fs_info *fs_info,
const struct btrfs_super_block *sb, int mirror_num)
{
u64 nodesize = btrfs_super_nodesize(sb);
u64 sectorsize = btrfs_super_sectorsize(sb);
int ret = 0;
const bool ignore_flags = btrfs_test_opt(fs_info, IGNORESUPERFLAGS);
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)) {
if (!ignore_flags) {
btrfs_err(fs_info,
"unrecognized or unsupported super flag 0x%llx",
btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
ret = -EINVAL;
} else {
btrfs_info(fs_info,
"unrecognized or unsupported super flags: 0x%llx, ignored",
btrfs_super_flags(sb) & ~BTRFS_SUPER_FLAG_SUPP);
}
}
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;
}
/*
* We only support at most two sectorsizes: 4K and PAGE_SIZE.
*
* We can support 16K sectorsize with 64K page size without problem,
* but such sectorsize/pagesize combination doesn't make much sense.
* 4K will be our future standard, PAGE_SIZE is supported from the very
* beginning.
*/
if (sectorsize > PAGE_SIZE || (sectorsize != SZ_4K && sectorsize != PAGE_SIZE)) {
btrfs_err(fs_info,
"sectorsize %llu not yet supported for page size %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 (!fs_info->fs_devices->temp_fsid &&
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;
}
/*
* Artificial requirement for block-group-tree to force newer features
* (free-space-tree, no-holes) so the test matrix is smaller.
*/
if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
(!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID) ||
!btrfs_fs_incompat(fs_info, NO_HOLES))) {
btrfs_err(fs_info,
"block-group-tree feature requires free-space-tree and no-holes");
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 btrfs_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 = btrfs_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 load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int level)
{
struct btrfs_tree_parent_check check = {
.level = level,
.transid = gen,
.owner_root = btrfs_root_id(root)
};
int ret = 0;
root->node = read_tree_block(root->fs_info, bytenr, &check);
if (IS_ERR(root->node)) {
ret = PTR_ERR(root->node);
root->node = NULL;
return ret;
}
if (!extent_buffer_uptodate(root->node)) {
free_extent_buffer(root->node);
root->node = NULL;
return -EIO;
}
btrfs_set_root_node(&root->root_item, root->node);
root->commit_root = btrfs_root_node(root);
btrfs_set_root_refs(&root->root_item, 1);
return ret;
}
static int load_important_roots(struct btrfs_fs_info *fs_info)
{
struct btrfs_super_block *sb = fs_info->super_copy;
u64 gen, bytenr;
int level, ret;
bytenr = btrfs_super_root(sb);
gen = btrfs_super_generation(sb);
level = btrfs_super_root_level(sb);
ret = load_super_root(fs_info->tree_root, bytenr, gen, level);
if (ret) {
btrfs_warn(fs_info, "couldn't read tree root");
return ret;
}
return 0;
}
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++) {
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);
btrfs_warn(fs_info, "try to load backup roots slot %d", i);
ret = read_backup_root(fs_info, i);
backup_index = ret;
if (ret < 0)
return ret;
}
ret = load_important_roots(fs_info);
if (ret) {
handle_error = true;
continue;
}
/*
* No need to hold btrfs_root::objectid_mutex since the fs
* hasn't been fully initialised and we are the only user
*/
ret = btrfs_init_root_free_objectid(tree_root);
if (ret < 0) {
handle_error = true;
continue;
}
ASSERT(tree_root->free_objectid <= BTRFS_LAST_FREE_OBJECTID);
ret = btrfs_read_roots(fs_info);
if (ret < 0) {
handle_error = true;
continue;
}
/* All successful */
fs_info->generation = btrfs_header_generation(tree_root->node);
btrfs_set_last_trans_committed(fs_info, fs_info->generation);
fs_info->last_reloc_trans = 0;
/* 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);
spin_lock_init(&fs_info->treelog_bg_lock);
spin_lock_init(&fs_info->zone_active_bgs_lock);
spin_lock_init(&fs_info->relocation_bg_lock);
rwlock_init(&fs_info->tree_mod_log_lock);
rwlock_init(&fs_info->global_root_lock);
mutex_init(&fs_info->unused_bg_unpin_mutex);
mutex_init(&fs_info->reclaim_bgs_lock);
mutex_init(&fs_info->reloc_mutex);
mutex_init(&fs_info->delalloc_root_mutex);
mutex_init(&fs_info->zoned_meta_io_lock);
mutex_init(&fs_info->zoned_data_reloc_io_lock);
seqlock_init(&fs_info->profiles_lock);
btrfs_lockdep_init_map(fs_info, btrfs_trans_num_writers);
btrfs_lockdep_init_map(fs_info, btrfs_trans_num_extwriters);
btrfs_lockdep_init_map(fs_info, btrfs_trans_pending_ordered);
btrfs_lockdep_init_map(fs_info, btrfs_ordered_extent);
btrfs_state_lockdep_init_map(fs_info, btrfs_trans_commit_prep,
BTRFS_LOCKDEP_TRANS_COMMIT_PREP);
btrfs_state_lockdep_init_map(fs_info, btrfs_trans_unblocked,
BTRFS_LOCKDEP_TRANS_UNBLOCKED);
btrfs_state_lockdep_init_map(fs_info, btrfs_trans_super_committed,
BTRFS_LOCKDEP_TRANS_SUPER_COMMITTED);
btrfs_state_lockdep_init_map(fs_info, btrfs_trans_completed,
BTRFS_LOCKDEP_TRANS_COMPLETED);
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);
INIT_LIST_HEAD(&fs_info->reclaim_bgs);
INIT_LIST_HEAD(&fs_info->zone_active_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
fs_info->mapping_tree = RB_ROOT_CACHED;
rwlock_init(&fs_info->mapping_tree_lock);
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->nr_delayed_iputs, 0);
atomic64_set(&fs_info->tree_mod_seq, 0);
fs_info->global_root_tree = RB_ROOT;
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;
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);
btrfs_init_balance(fs_info);
btrfs_init_async_reclaim_work(fs_info);
rwlock_init(&fs_info->block_group_cache_lock);
fs_info->block_group_cache_tree = RB_ROOT_CACHED;
extent_io_tree_init(fs_info, &fs_info->excluded_extents,
IO_TREE_FS_EXCLUDED_EXTENTS);
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->sectorsize_bits = ilog2(4096);
fs_info->stripesize = 4096;
/* Default compress algorithm when user does -o compress */
fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
fs_info->max_extent_size = BTRFS_MAX_EXTENT_SIZE;
spin_lock_init(&fs_info->swapfile_pins_lock);
fs_info->swapfile_pins = RB_ROOT;
fs_info->bg_reclaim_threshold = BTRFS_DEFAULT_RECLAIM_THRESH;
INIT_WORK(&fs_info->reclaim_bgs_work, btrfs_reclaim_bgs_work);
}
static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
{
int ret;
fs_info->sb = sb;
/* Temporary fixed values for block size until we read the superblock. */
sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
if (ret)
return ret;
ret = percpu_counter_init(&fs_info->evictable_extent_maps, 0, GFP_KERNEL);
if (ret)
return ret;
spin_lock_init(&fs_info->extent_map_shrinker_lock);
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);
if (sb_rdonly(sb))
set_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state);
if (btrfs_test_opt(fs_info, IGNOREMETACSUMS))
set_bit(BTRFS_FS_STATE_SKIP_META_CSUMS, &fs_info->fs_state);
return btrfs_alloc_stripe_hash_table(fs_info);
}
static int btrfs_uuid_rescan_kthread(void *data)
{
struct btrfs_fs_info *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;
}
static int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
{
u64 root_objectid = 0;
struct btrfs_root *gang[8];
int ret = 0;
while (1) {
unsigned int found;
spin_lock(&fs_info->fs_roots_radix_lock);
found = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
(void **)gang, root_objectid,
ARRAY_SIZE(gang));
if (!found) {
spin_unlock(&fs_info->fs_roots_radix_lock);
break;
}
root_objectid = btrfs_root_id(gang[found - 1]) + 1;
for (int i = 0; i < found; 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 (int i = 0; i < found; i++) {
if (!gang[i])
continue;
root_objectid = btrfs_root_id(gang[i]);
/*
* Continue to release the remaining roots after the first
* error without cleanup and preserve the first error
* for the return.
*/
if (!ret)
ret = btrfs_orphan_cleanup(gang[i]);
btrfs_put_root(gang[i]);
}
if (ret)
break;
root_objectid++;
}
return ret;
}
/*
* Mounting logic specific to read-write file systems. Shared by open_ctree
* and btrfs_remount when remounting from read-only to read-write.
*/
int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info)
{
int ret;
const bool cache_opt = btrfs_test_opt(fs_info, SPACE_CACHE);
bool rebuild_free_space_tree = false;
if (btrfs_test_opt(fs_info, CLEAR_CACHE) &&
btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
btrfs_warn(fs_info,
"'clear_cache' option is ignored with extent tree v2");
else
rebuild_free_space_tree = true;
} 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");
rebuild_free_space_tree = true;
}
if (rebuild_free_space_tree) {
btrfs_info(fs_info, "rebuilding free space tree");
ret = btrfs_rebuild_free_space_tree(fs_info);
if (ret) {
btrfs_warn(fs_info,
"failed to rebuild free space tree: %d", ret);
goto out;
}
}
if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
!btrfs_test_opt(fs_info, FREE_SPACE_TREE)) {
btrfs_info(fs_info, "disabling free space tree");
ret = btrfs_delete_free_space_tree(fs_info);
if (ret) {
btrfs_warn(fs_info,
"failed to disable free space tree: %d", ret);
goto out;
}
}
/*
* btrfs_find_orphan_roots() is responsible for finding all the dead
* roots (with 0 refs), flag them with BTRFS_ROOT_DEAD_TREE and load
* them into the fs_info->fs_roots_radix tree. This must be done before
* calling btrfs_orphan_cleanup() on the tree root. If we don't do it
* first, then btrfs_orphan_cleanup() will delete a dead root's orphan
* item before the root's tree is deleted - this means that if we unmount
* or crash before the deletion completes, on the next mount we will not
* delete what remains of the tree because the orphan item does not
* exists anymore, which is what tells us we have a pending deletion.
*/
ret = btrfs_find_orphan_roots(fs_info);
if (ret)
goto out;
ret = btrfs_cleanup_fs_roots(fs_info);
if (ret)
goto out;
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);
goto out;
}
up_read(&fs_info->cleanup_work_sem);
mutex_lock(&fs_info->cleaner_mutex);
ret = btrfs_recover_relocation(fs_info);
mutex_unlock(&fs_info->cleaner_mutex);
if (ret < 0) {
btrfs_warn(fs_info, "failed to recover relocation: %d", ret);
goto out;
}
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);
goto out;
}
}
if (cache_opt != btrfs_free_space_cache_v1_active(fs_info)) {
ret = btrfs_set_free_space_cache_v1_active(fs_info, cache_opt);
if (ret)
goto out;
}
ret = btrfs_resume_balance_async(fs_info);
if (ret)
goto out;
ret = btrfs_resume_dev_replace_async(fs_info);
if (ret) {
btrfs_warn(fs_info, "failed to resume dev_replace");
goto out;
}
btrfs_qgroup_rescan_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);
goto out;
}
}
out:
return ret;
}
/*
* Do various sanity and dependency checks of different features.
*
* @is_rw_mount: If the mount is read-write.
*
* This is the place for less strict checks (like for subpage or artificial
* feature dependencies).
*
* For strict checks or possible corruption detection, see
* btrfs_validate_super().
*
* This should be called after btrfs_parse_options(), as some mount options
* (space cache related) can modify on-disk format like free space tree and
* screw up certain feature dependencies.
*/
int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount)
{
struct btrfs_super_block *disk_super = fs_info->super_copy;
u64 incompat = btrfs_super_incompat_flags(disk_super);
const u64 compat_ro = btrfs_super_compat_ro_flags(disk_super);
const u64 compat_ro_unsupp = (compat_ro & ~BTRFS_FEATURE_COMPAT_RO_SUPP);
if (incompat & ~BTRFS_FEATURE_INCOMPAT_SUPP) {
btrfs_err(fs_info,
"cannot mount because of unknown incompat features (0x%llx)",
incompat);
return -EINVAL;
}
/* Runtime limitation for mixed block groups. */
if ((incompat & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
(fs_info->sectorsize != fs_info->nodesize)) {
btrfs_err(fs_info,
"unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
fs_info->nodesize, fs_info->sectorsize);
return -EINVAL;
}
/* Mixed backref is an always-enabled feature. */
incompat |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
/* Set compression related flags just in case. */
if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
else if (fs_info->compress_type == BTRFS_COMPRESS_ZSTD)
incompat |= BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD;
/*
* An ancient flag, which should really be marked deprecated.
* Such runtime limitation doesn't really need a incompat flag.
*/
if (btrfs_super_nodesize(disk_super) > PAGE_SIZE)
incompat |= BTRFS_FEATURE_INCOMPAT_BIG_METADATA;
if (compat_ro_unsupp && is_rw_mount) {
btrfs_err(fs_info,
"cannot mount read-write because of unknown compat_ro features (0x%llx)",
compat_ro);
return -EINVAL;
}
/*
* We have unsupported RO compat features, although RO mounted, we
* should not cause any metadata writes, including log replay.
* Or we could screw up whatever the new feature requires.
*/
if (compat_ro_unsupp && 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",
compat_ro);
return -EINVAL;
}
/*
* Artificial limitations for block group tree, to force
* block-group-tree to rely on no-holes and free-space-tree.
*/
if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE) &&
(!btrfs_fs_incompat(fs_info, NO_HOLES) ||
!btrfs_test_opt(fs_info, FREE_SPACE_TREE))) {
btrfs_err(fs_info,
"block-group-tree feature requires no-holes and free-space-tree features");
return -EINVAL;
}
/*
* Subpage runtime limitation on v1 cache.
*
* V1 space cache still has some hard codeed PAGE_SIZE usage, while
* we're already defaulting to v2 cache, no need to bother v1 as it's
* going to be deprecated anyway.
*/
if (fs_info->sectorsize < PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) {
btrfs_warn(fs_info,
"v1 space cache is not supported for page size %lu with sectorsize %u",
PAGE_SIZE, fs_info->sectorsize);
return -EINVAL;
}
/* This can be called by remount, we need to protect the super block. */
spin_lock(&fs_info->super_lock);
btrfs_set_super_incompat_flags(disk_super, incompat);
spin_unlock(&fs_info->super_lock);
return 0;
}
int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
const char *options)
{
u32 sectorsize;
u32 nodesize;
u32 stripesize;
u64 generation;
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 level;
ret = init_mount_fs_info(fs_info, sb);
if (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) {
ret = -ENOMEM;
goto fail;
}
ret = btrfs_init_btree_inode(sb);
if (ret)
goto fail;
invalidate_bdev(fs_devices->latest_dev->bdev);
/*
* Read super block and check the signature bytes only
*/
disk_super = btrfs_read_dev_super(fs_devices->latest_dev->bdev);
if (IS_ERR(disk_super)) {
ret = PTR_ERR(disk_super);
goto fail_alloc;
}
btrfs_info(fs_info, "first mount of filesystem %pU", disk_super->fsid);
/*
* 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);
ret = -EINVAL;
btrfs_release_disk_super(disk_super);
goto fail_alloc;
}
fs_info->csum_size = btrfs_super_csum_size(disk_super);
ret = btrfs_init_csum_hash(fs_info, csum_type);
if (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, disk_super)) {
btrfs_err(fs_info, "superblock checksum mismatch");
ret = -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;
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");
ret = -EINVAL;
goto fail_alloc;
}
if (!btrfs_super_root(disk_super)) {
btrfs_err(fs_info, "invalid superblock tree root bytenr");
ret = -EINVAL;
goto fail_alloc;
}
/* check FS state, whether FS is broken. */
if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
WRITE_ONCE(fs_info->fs_error, -EUCLEAN);
/* 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));
fs_info->nodesize = nodesize;
fs_info->sectorsize = sectorsize;
fs_info->sectorsize_bits = ilog2(sectorsize);
fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
fs_info->stripesize = stripesize;
/*
* Handle the space caching options appropriately now that we have the
* super block loaded and validated.
*/
btrfs_set_free_space_cache_settings(fs_info);
if (!btrfs_check_options(fs_info, &fs_info->mount_opt, sb->s_flags)) {
ret = -EINVAL;
goto fail_alloc;
}
ret = btrfs_check_features(fs_info, !sb_rdonly(sb));
if (ret < 0)
goto fail_alloc;
/*
* At this point our mount options are validated, if we set ->max_inline
* to something non-standard make sure we truncate it to sectorsize.
*/
fs_info->max_inline = min_t(u64, fs_info->max_inline, fs_info->sectorsize);
if (sectorsize < PAGE_SIZE) {
struct btrfs_subpage_info *subpage_info;
btrfs_warn(fs_info,
"read-write for sector size %u with page size %lu is experimental",
sectorsize, PAGE_SIZE);
subpage_info = kzalloc(sizeof(*subpage_info), GFP_KERNEL);
if (!subpage_info) {
ret = -ENOMEM;
goto fail_alloc;
}
btrfs_init_subpage_info(subpage_info, sectorsize);
fs_info->subpage_info = subpage_info;
}
ret = btrfs_init_workqueues(fs_info);
if (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);
/* Update the values for the current filesystem. */
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);
ret = load_super_root(chunk_root, btrfs_super_chunk_root(disk_super),
generation, level);
if (ret) {
btrfs_err(fs_info, "failed to read chunk root");
goto fail_tree_roots;
}
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;
}
/*
* At this point we know all the devices that make this filesystem,
* including the seed devices but we don't know yet if the replace
* target is required. So free devices that are not part of this
* filesystem but skip the replace target device which is checked
* below in btrfs_init_dev_replace().
*/
btrfs_free_extra_devids(fs_devices);
if (!fs_devices->latest_dev->bdev) {
btrfs_err(fs_info, "failed to read devices");
ret = -EIO;
goto fail_tree_roots;
}
ret = init_tree_roots(fs_info);
if (ret)
goto fail_tree_roots;
/*
* Get zone type information of zoned block devices. This will also
* handle emulation of a zoned filesystem if a regular device has the
* zoned incompat feature flag set.
*/
ret = btrfs_get_dev_zone_info_all_devices(fs_info);
if (ret) {
btrfs_err(fs_info,
"zoned: failed to read device zone info: %d", ret);
goto fail_block_groups;
}
/*
* 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;
}
ret = btrfs_check_zoned_mode(fs_info);
if (ret) {
btrfs_err(fs_info, "failed to initialize zoned mode: %d",
ret);
goto fail_block_groups;
}
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;
}
btrfs_free_zone_cache(fs_info);
btrfs_check_active_zone_reservation(fs_info);
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");
ret = -EINVAL;
goto fail_sysfs;
}
fs_info->cleaner_kthread = kthread_run(cleaner_kthread, fs_info,
"btrfs-cleaner");
if (IS_ERR(fs_info->cleaner_kthread)) {
ret = PTR_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)) {
ret = PTR_ERR(fs_info->transaction_kthread);
goto fail_cleaner;
}
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)
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)) {
ret = PTR_ERR(fs_info->fs_root);
btrfs_warn(fs_info, "failed to read fs tree: %d", ret);
fs_info->fs_root = NULL;
goto fail_qgroup;
}
if (sb_rdonly(sb))
return 0;
ret = btrfs_start_pre_rw_mount(fs_info);
if (ret) {
close_ctree(fs_info);
return ret;
}
btrfs_discard_resume(fs_info);
if (fs_info->uuid_root &&
(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);
/* Kick the cleaner thread so it'll start deleting snapshots. */
if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
wake_up_process(fs_info->cleaner_kthread);
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);
iput(fs_info->btree_inode);
fail:
btrfs_close_devices(fs_info->fs_devices);
ASSERT(ret < 0);
return ret;
}
ALLOW_ERROR_INJECTION(open_ctree, ERRNO);
static void btrfs_end_super_write(struct bio *bio)
{
struct btrfs_device *device = bio->bi_private;
struct folio_iter fi;
bio_for_each_folio_all(fi, bio) {
if (bio->bi_status) {
btrfs_warn_rl_in_rcu(device->fs_info,
"lost super block write due to IO error on %s (%d)",
btrfs_dev_name(device),
blk_status_to_errno(bio->bi_status));
btrfs_dev_stat_inc_and_print(device,
BTRFS_DEV_STAT_WRITE_ERRS);
/* Ensure failure if the primary sb fails. */
if (bio->bi_opf & REQ_FUA)
atomic_add(BTRFS_SUPER_PRIMARY_WRITE_ERROR,
&device->sb_write_errors);
else
atomic_inc(&device->sb_write_errors);
}
folio_unlock(fi.folio);
folio_put(fi.folio);
}
bio_put(bio);
}
struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
int copy_num, bool drop_cache)
{
struct btrfs_super_block *super;
struct page *page;
u64 bytenr, bytenr_orig;
struct address_space *mapping = bdev->bd_mapping;
int ret;
bytenr_orig = btrfs_sb_offset(copy_num);
ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
if (ret == -ENOENT)
return ERR_PTR(-EINVAL);
else if (ret)
return ERR_PTR(ret);
if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev))
return ERR_PTR(-EINVAL);
if (drop_cache) {
/* This should only be called with the primary sb. */
ASSERT(copy_num == 0);
/*
* Drop the page of the primary superblock, so later read will
* always read from the device.
*/
invalidate_inode_pages2_range(mapping,
bytenr >> PAGE_SHIFT,
(bytenr + BTRFS_SUPER_INFO_SIZE) >> PAGE_SHIFT);
}
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_orig) {
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, false);
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
* folios 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 folio 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_mapping;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
int i;
int ret;
u64 bytenr, bytenr_orig;
atomic_set(&device->sb_write_errors, 0);
if (max_mirrors == 0)
max_mirrors = BTRFS_SUPER_MIRROR_MAX;
shash->tfm = fs_info->csum_shash;
for (i = 0; i < max_mirrors; i++) {
struct folio *folio;
struct bio *bio;
struct btrfs_super_block *disk_super;
size_t offset;
bytenr_orig = btrfs_sb_offset(i);
ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
if (ret == -ENOENT) {
continue;
} else if (ret < 0) {
btrfs_err(device->fs_info,
"couldn't get super block location for mirror %d",
i);
atomic_inc(&device->sb_write_errors);
continue;
}
if (bytenr + BTRFS_SUPER_INFO_SIZE >=
device->commit_total_bytes)
break;
btrfs_set_super_bytenr(sb, bytenr_orig);
crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
sb->csum);
folio = __filemap_get_folio(mapping, bytenr >> PAGE_SHIFT,
FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
GFP_NOFS);
if (IS_ERR(folio)) {
btrfs_err(device->fs_info,
"couldn't get super block page for bytenr %llu",
bytenr);
atomic_inc(&device->sb_write_errors);
continue;
}
ASSERT(folio_order(folio) == 0);
offset = offset_in_folio(folio, bytenr);
disk_super = folio_address(folio) + offset;
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(device->bdev, 1,
REQ_OP_WRITE | REQ_SYNC | REQ_META | REQ_PRIO,
GFP_NOFS);
bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT;
bio->bi_private = device;
bio->bi_end_io = btrfs_end_super_write;
bio_add_folio_nofail(bio, folio, BTRFS_SUPER_INFO_SIZE, offset);
/*
* 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.
*/
if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER))
bio->bi_opf |= REQ_FUA;
submit_bio(bio);
if (btrfs_advance_sb_log(device, i))
atomic_inc(&device->sb_write_errors);
}
return atomic_read(&device->sb_write_errors) < i ? 0 : -1;
}
/*
* Wait for write completion of superblocks done by write_dev_supers,
* @max_mirrors same for write and wait phases.
*
* Return -1 if primary super block write failed or when there were no super block
* copies written. Otherwise 0.
*/
static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
{
int i;
int errors = 0;
bool primary_failed = false;
int ret;
u64 bytenr;
if (max_mirrors == 0)
max_mirrors = BTRFS_SUPER_MIRROR_MAX;
for (i = 0; i < max_mirrors; i++) {
struct folio *folio;
ret = btrfs_sb_log_location(device, i, READ, &bytenr);
if (ret == -ENOENT) {
break;
} else if (ret < 0) {
errors++;
if (i == 0)
primary_failed = true;
continue;
}
if (bytenr + BTRFS_SUPER_INFO_SIZE >=
device->commit_total_bytes)
break;
folio = filemap_get_folio(device->bdev->bd_mapping,
bytenr >> PAGE_SHIFT);
/* If the folio has been removed, then we know it completed. */
if (IS_ERR(folio))
continue;
ASSERT(folio_order(folio) == 0);
/* Folio will be unlocked once the write completes. */
folio_wait_locked(folio);
folio_put(folio);
}
errors += atomic_read(&device->sb_write_errors);
if (errors >= BTRFS_SUPER_PRIMARY_WRITE_ERROR)
primary_failed = true;
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)
{
bio_uninit(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;
device->last_flush_error = BLK_STS_OK;
bio_init(bio, device->bdev, NULL, 0,
REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH);
bio->bi_end_io = btrfs_end_empty_barrier;
init_completion(&device->flush_wait);
bio->bi_private = &device->flush_wait;
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.
* Return true for any error, and false otherwise.
*/
static bool wait_dev_flush(struct btrfs_device *device)
{
struct bio *bio = &device->flush_bio;
if (!test_and_clear_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state))
return false;
wait_for_completion_io(&device->flush_wait);
if (bio->bi_status) {
device->last_flush_error = bio->bi_status;
btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_FLUSH_ERRS);
return true;
}
return false;
}
/*
* 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;
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);
}
/* 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;
if (wait_dev_flush(dev))
errors_wait++;
}
/*
* Checks last_flush_error of disks in order to determine the device
* state.
*/
if (errors_wait && !btrfs_check_rw_degradable(info, NULL))
return -EIO;
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)btrfs_root_id(root));
if (test_and_clear_bit(BTRFS_ROOT_IN_RADIX, &root->state))
drop_ref = true;
spin_unlock(&fs_info->fs_roots_radix_lock);
if (BTRFS_FS_ERROR(fs_info)) {
ASSERT(root->log_root == NULL);
if (root->reloc_root) {
btrfs_put_root(root->reloc_root);
root->reloc_root = NULL;
}
}
if (drop_ref)
btrfs_put_root(root);
}
int btrfs_commit_super(struct btrfs_fs_info *fs_info)
{
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);
return btrfs_commit_current_transaction(fs_info->tree_root);
}
static void warn_about_uncommitted_trans(struct btrfs_fs_info *fs_info)
{
struct btrfs_transaction *trans;
struct btrfs_transaction *tmp;
bool found = false;
/*
* This function is only called at the very end of close_ctree(),
* thus no other running transaction, no need to take trans_lock.
*/
ASSERT(test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags));
list_for_each_entry_safe(trans, tmp, &fs_info->trans_list, list) {
struct extent_state *cached = NULL;
u64 dirty_bytes = 0;
u64 cur = 0;
u64 found_start;
u64 found_end;
found = true;
while (find_first_extent_bit(&trans->dirty_pages, cur,
&found_start, &found_end, EXTENT_DIRTY, &cached)) {
dirty_bytes += found_end + 1 - found_start;
cur = found_end + 1;
}
btrfs_warn(fs_info,
"transaction %llu (with %llu dirty metadata bytes) is not committed",
trans->transid, dirty_bytes);
btrfs_cleanup_one_transaction(trans, fs_info);
if (trans == fs_info->running_transaction)
fs_info->running_transaction = NULL;
list_del_init(&trans->list);
btrfs_put_transaction(trans);
trace_btrfs_transaction_commit(fs_info);
}
ASSERT(!found);
}
void __cold close_ctree(struct btrfs_fs_info *fs_info)
{
int ret;
set_bit(BTRFS_FS_CLOSING_START, &fs_info->flags);
/*
* If we had UNFINISHED_DROPS we could still be processing them, so
* clear that bit and wake up relocation so it can stop.
* We must do this before stopping the block group reclaim task, because
* at btrfs_relocate_block_group() we wait for this bit, and after the
* wait we stop with -EINTR if btrfs_fs_closing() returns non-zero - we
* have just set BTRFS_FS_CLOSING_START, so btrfs_fs_closing() will
* return 1.
*/
btrfs_wake_unfinished_drop(fs_info);
/*
* We may have the reclaim task running and relocating a data block group,
* in which case it may create delayed iputs. So stop it before we park
* the cleaner kthread otherwise we can get new delayed iputs after
* parking the cleaner, and that can make the async reclaim task to hang
* if it's waiting for delayed iputs to complete, since the cleaner is
* parked and can not run delayed iputs - this will make us hang when
* trying to stop the async reclaim task.
*/
cancel_work_sync(&fs_info->reclaim_bgs_work);
/*
* 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_work_sync(&fs_info->preempt_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 (BTRFS_FS_ERROR(fs_info))
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->ordered_bytes))
btrfs_info(fs_info, "at unmount dio bytes count %lld",
percpu_counter_sum(&fs_info->ordered_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);
/* We shouldn't have any transaction open at this point */
warn_about_uncommitted_trans(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);
btrfs_mapping_tree_free(fs_info);
btrfs_close_devices(fs_info->fs_devices);
}
void btrfs_mark_buffer_dirty(struct btrfs_trans_handle *trans,
struct extent_buffer *buf)
{
struct btrfs_fs_info *fs_info = buf->fs_info;
u64 transid = btrfs_header_generation(buf);
#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
/* This is an active transaction (its state < TRANS_STATE_UNBLOCKED). */
ASSERT(trans->transid == fs_info->generation);
btrfs_assert_tree_write_locked(buf);
if (unlikely(transid != fs_info->generation)) {
btrfs_abort_transaction(trans, -EUCLEAN);
btrfs_crit(fs_info,
"dirty buffer transid mismatch, logical %llu found transid %llu running transid %llu",
buf->start, transid, fs_info->generation);
}
set_extent_buffer_dirty(buf);
}
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);
}
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 = btrfs_root_id(gang[i]);
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;
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, NULL);
}
static void 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 = &trans->delayed_refs;
struct btrfs_delayed_ref_node *ref;
spin_lock(&delayed_refs->lock);
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);
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);
btrfs_delayed_refs_rsv_release(fs_info, 1, 0);
}
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);
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);
}
static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
{
struct btrfs_inode *btrfs_inode;
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(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;
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 void btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
struct extent_io_tree *dirty_pages,
int mark)
{
struct extent_buffer *eb;
u64 start = 0;
u64 end;
while (find_first_extent_bit(dirty_pages, start, &start, &end,
mark, NULL)) {
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;
btrfs_tree_lock(eb);
wait_on_extent_buffer_writeback(eb);
btrfs_clear_buffer_dirty(NULL, eb);
btrfs_tree_unlock(eb);
free_extent_buffer_stale(eb);
}
}
}
static void btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
struct extent_io_tree *unpin)
{
u64 start;
u64 end;
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);
if (!find_first_extent_bit(unpin, 0, &start, &end,
EXTENT_DIRTY, &cached_state)) {
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();
}
}
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_dec_delayed_refs_rsv_bg_updates(fs_info);
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);
}
}
static void btrfs_free_all_qgroup_pertrans(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *gang[8];
int i;
int ret;
spin_lock(&fs_info->fs_roots_radix_lock);
while (1) {
ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
(void **)gang, 0,
ARRAY_SIZE(gang),
BTRFS_ROOT_TRANS_TAG);
if (ret == 0)
break;
for (i = 0; i < ret; i++) {
struct btrfs_root *root = gang[i];
btrfs_qgroup_free_meta_all_pertrans(root);
radix_tree_tag_clear(&fs_info->fs_roots_radix,
(unsigned long)btrfs_root_id(root),
BTRFS_ROOT_TRANS_TAG);
}
}
spin_unlock(&fs_info->fs_roots_radix_lock);
}
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_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_PREP) {
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);
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);
btrfs_free_all_qgroup_pertrans(fs_info);
mutex_unlock(&fs_info->transaction_kthread_mutex);
return 0;
}
int btrfs_init_root_free_objectid(struct btrfs_root *root)
{
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;
if (ret == 0) {
/*
* Key with offset -1 found, there would have to exist a root
* with such id, but this is out of valid range.
*/
ret = -EUCLEAN;
goto error;
}
if (path->slots[0] > 0) {
slot = path->slots[0] - 1;
l = path->nodes[0];
btrfs_item_key_to_cpu(l, &found_key, slot);
root->free_objectid = max_t(u64, found_key.objectid + 1,
BTRFS_FIRST_FREE_OBJECTID);
} else {
root->free_objectid = BTRFS_FIRST_FREE_OBJECTID;
}
ret = 0;
error:
btrfs_free_path(path);
return ret;
}
int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid)
{
int ret;
mutex_lock(&root->objectid_mutex);
if (unlikely(root->free_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
btrfs_warn(root->fs_info,
"the objectid of root %llu reaches its highest value",
btrfs_root_id(root));
ret = -ENOSPC;
goto out;
}
*objectid = root->free_objectid++;
ret = 0;
out:
mutex_unlock(&root->objectid_mutex);
return ret;
}