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disk-io.c
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// 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 "check-integrity.h"
#include "rcu-string.h"
#include "dev-replace.h"
#include "raid56.h"
#include "sysfs.h"
#include "qgroup.h"
#include "compression.h"
#include "tree-checker.h"
#include "ref-verify.h"
#include "block-group.h"
#include "discard.h"
#include "space-info.h"
#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 void btrfs_destroy_ordered_extents(struct btrfs_root *root);
static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
struct btrfs_fs_info *fs_info);
static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
struct extent_io_tree *dirty_pages,
int mark);
static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
struct extent_io_tree *pinned_extents);
static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
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;
const int num_pages = num_extent_pages(buf);
const int first_page_part = min_t(u32, PAGE_SIZE, fs_info->nodesize);
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
char *kaddr;
int i;
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
kaddr = page_address(buf->pages[0]) + offset_in_page(buf->start);
crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE,
first_page_part - BTRFS_CSUM_SIZE);
for (i = 1; i < num_pages; i++) {
kaddr = page_address(buf->pages[i]);
crypto_shash_update(shash, kaddr, PAGE_SIZE);
}
memset(result, 0, BTRFS_CSUM_SIZE);
crypto_shash_final(shash, result);
}
/*
* we can't consider a given block up to date unless the transid of the
* block matches the transid in the parent node's pointer. This is how we
* detect blocks that either didn't get written at all or got written
* in the wrong place.
*/
static int verify_parent_transid(struct extent_io_tree *io_tree,
struct extent_buffer *eb, u64 parent_transid,
int atomic)
{
struct extent_state *cached_state = NULL;
int ret;
if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
return 0;
if (atomic)
return -EAGAIN;
lock_extent(io_tree, eb->start, eb->start + eb->len - 1, &cached_state);
if (extent_buffer_uptodate(eb) &&
btrfs_header_generation(eb) == parent_transid) {
ret = 0;
goto out;
}
btrfs_err_rl(eb->fs_info,
"parent transid verify failed on logical %llu mirror %u wanted %llu found %llu",
eb->start, eb->read_mirror,
parent_transid, btrfs_header_generation(eb));
ret = 1;
clear_extent_buffer_uptodate(eb);
out:
unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
&cached_state);
return ret;
}
static bool btrfs_supported_super_csum(u16 csum_type)
{
switch (csum_type) {
case BTRFS_CSUM_TYPE_CRC32:
case BTRFS_CSUM_TYPE_XXHASH:
case BTRFS_CSUM_TYPE_SHA256:
case BTRFS_CSUM_TYPE_BLAKE2:
return true;
default:
return false;
}
}
/*
* Return 0 if the superblock checksum type matches the checksum value of that
* algorithm. Pass the raw disk superblock data.
*/
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;
}
int btrfs_verify_level_key(struct extent_buffer *eb, int level,
struct btrfs_key *first_key, u64 parent_transid)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
int found_level;
struct btrfs_key found_key;
int ret;
found_level = btrfs_header_level(eb);
if (found_level != level) {
WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
KERN_ERR "BTRFS: tree level check failed\n");
btrfs_err(fs_info,
"tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
eb->start, level, found_level);
return -EIO;
}
if (!first_key)
return 0;
/*
* For live tree block (new tree blocks in current transaction),
* we need proper lock context to avoid race, which is impossible here.
* So we only checks tree blocks which is read from disk, whose
* generation <= fs_info->last_trans_committed.
*/
if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
return 0;
/* We have @first_key, so this @eb must have at least one item */
if (btrfs_header_nritems(eb) == 0) {
btrfs_err(fs_info,
"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
eb->start);
WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
return -EUCLEAN;
}
if (found_level)
btrfs_node_key_to_cpu(eb, &found_key, 0);
else
btrfs_item_key_to_cpu(eb, &found_key, 0);
ret = btrfs_comp_cpu_keys(first_key, &found_key);
if (ret) {
WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
KERN_ERR "BTRFS: tree first key check failed\n");
btrfs_err(fs_info,
"tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
eb->start, parent_transid, first_key->objectid,
first_key->type, first_key->offset,
found_key.objectid, found_key.type,
found_key.offset);
}
return ret;
}
static int btrfs_repair_eb_io_failure(const struct extent_buffer *eb,
int mirror_num)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
u64 start = eb->start;
int i, num_pages = num_extent_pages(eb);
int ret = 0;
if (sb_rdonly(fs_info->sb))
return -EROFS;
for (i = 0; i < num_pages; i++) {
struct page *p = eb->pages[i];
ret = btrfs_repair_io_failure(fs_info, 0, start, PAGE_SIZE,
start, p, start - page_offset(p), mirror_num);
if (ret)
break;
start += PAGE_SIZE;
}
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,
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;
}
static int csum_one_extent_buffer(struct extent_buffer *eb)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
u8 result[BTRFS_CSUM_SIZE];
int ret;
ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
offsetof(struct btrfs_header, fsid),
BTRFS_FSID_SIZE) == 0);
csum_tree_block(eb, result);
if (btrfs_header_level(eb))
ret = btrfs_check_node(eb);
else
ret = btrfs_check_leaf_full(eb);
if (ret < 0)
goto error;
/*
* Also check the generation, the eb reached here must be newer than
* last committed. Or something seriously wrong happened.
*/
if (unlikely(btrfs_header_generation(eb) <= fs_info->last_trans_committed)) {
ret = -EUCLEAN;
btrfs_err(fs_info,
"block=%llu bad generation, have %llu expect > %llu",
eb->start, btrfs_header_generation(eb),
fs_info->last_trans_committed);
goto error;
}
write_extent_buffer(eb, result, 0, fs_info->csum_size);
return 0;
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 ret;
}
/* Checksum all dirty extent buffers in one bio_vec */
static int csum_dirty_subpage_buffers(struct btrfs_fs_info *fs_info,
struct bio_vec *bvec)
{
struct page *page = bvec->bv_page;
u64 bvec_start = page_offset(page) + bvec->bv_offset;
u64 cur;
int ret = 0;
for (cur = bvec_start; cur < bvec_start + bvec->bv_len;
cur += fs_info->nodesize) {
struct extent_buffer *eb;
bool uptodate;
eb = find_extent_buffer(fs_info, cur);
uptodate = btrfs_subpage_test_uptodate(fs_info, page, cur,
fs_info->nodesize);
/* A dirty eb shouldn't disappear from buffer_radix */
if (WARN_ON(!eb))
return -EUCLEAN;
if (WARN_ON(cur != btrfs_header_bytenr(eb))) {
free_extent_buffer(eb);
return -EUCLEAN;
}
if (WARN_ON(!uptodate)) {
free_extent_buffer(eb);
return -EUCLEAN;
}
ret = csum_one_extent_buffer(eb);
free_extent_buffer(eb);
if (ret < 0)
return ret;
}
return ret;
}
/*
* Checksum a dirty tree block before IO. This has extra checks to make sure
* we only fill in the checksum field in the first page of a multi-page block.
* For subpage extent buffers we need bvec to also read the offset in the page.
*/
static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct bio_vec *bvec)
{
struct page *page = bvec->bv_page;
u64 start = page_offset(page);
u64 found_start;
struct extent_buffer *eb;
if (fs_info->nodesize < PAGE_SIZE)
return csum_dirty_subpage_buffers(fs_info, bvec);
eb = (struct extent_buffer *)page->private;
if (page != eb->pages[0])
return 0;
found_start = btrfs_header_bytenr(eb);
if (test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags)) {
WARN_ON(found_start != 0);
return 0;
}
/*
* Please do not consolidate these warnings into a single if.
* It is useful to know what went wrong.
*/
if (WARN_ON(found_start != start))
return -EUCLEAN;
if (WARN_ON(!PageUptodate(page)))
return -EUCLEAN;
return csum_one_extent_buffer(eb);
}
blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio)
{
struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
struct bvec_iter iter;
struct bio_vec bv;
int ret = 0;
bio_for_each_segment(bv, &bbio->bio, iter) {
ret = csum_dirty_buffer(fs_info, &bv);
if (ret)
break;
}
return errno_to_blk_status(ret);
}
static int check_tree_block_fsid(struct extent_buffer *eb)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
u8 fsid[BTRFS_FSID_SIZE];
u8 *metadata_uuid;
read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
BTRFS_FSID_SIZE);
/*
* Checking the incompat flag is only valid for the current fs. For
* seed devices it's forbidden to have their uuid changed so reading
* ->fsid in this case is fine
*/
if (btrfs_fs_incompat(fs_info, METADATA_UUID))
metadata_uuid = fs_devices->metadata_uuid;
else
metadata_uuid = fs_devices->fsid;
if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
return 0;
list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
return 0;
return 1;
}
/* Do basic extent buffer checks at read time */
static int validate_extent_buffer(struct extent_buffer *eb,
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;
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 = page_address(eb->pages[0]) +
get_eb_offset_in_page(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",
eb->start, eb->read_mirror,
CSUM_FMT_VALUE(csum_size, header_csum),
CSUM_FMT_VALUE(csum_size, result),
btrfs_header_level(eb));
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) {
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_full(eb)) {
set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
ret = -EIO;
}
if (found_level > 0 && btrfs_check_node(eb))
ret = -EIO;
if (!ret)
set_extent_buffer_uptodate(eb);
else
btrfs_err(fs_info,
"read time tree block corruption detected on logical %llu mirror %u",
eb->start, eb->read_mirror);
out:
return ret;
}
static int validate_subpage_buffer(struct page *page, u64 start, u64 end,
int mirror, struct btrfs_tree_parent_check *check)
{
struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
struct extent_buffer *eb;
bool reads_done;
int ret = 0;
ASSERT(check);
/*
* We don't allow bio merge for subpage metadata read, so we should
* only get one eb for each endio hook.
*/
ASSERT(end == start + fs_info->nodesize - 1);
ASSERT(PagePrivate(page));
eb = find_extent_buffer(fs_info, start);
/*
* When we are reading one tree block, eb must have been inserted into
* the radix tree. If not, something is wrong.
*/
ASSERT(eb);
reads_done = atomic_dec_and_test(&eb->io_pages);
/* Subpage read must finish in page read */
ASSERT(reads_done);
eb->read_mirror = mirror;
if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
ret = -EIO;
goto err;
}
ret = validate_extent_buffer(eb, check);
if (ret < 0)
goto err;
set_extent_buffer_uptodate(eb);
free_extent_buffer(eb);
return ret;
err:
/*
* end_bio_extent_readpage decrements io_pages in case of error,
* make sure it has something to decrement.
*/
atomic_inc(&eb->io_pages);
clear_extent_buffer_uptodate(eb);
free_extent_buffer(eb);
return ret;
}
int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
struct page *page, u64 start, u64 end,
int mirror)
{
struct extent_buffer *eb;
int ret = 0;
int reads_done;
ASSERT(page->private);
if (btrfs_sb(page->mapping->host->i_sb)->nodesize < PAGE_SIZE)
return validate_subpage_buffer(page, start, end, mirror,
&bbio->parent_check);
eb = (struct extent_buffer *)page->private;
/*
* The pending IO might have been the only thing that kept this buffer
* in memory. Make sure we have a ref for all this other checks
*/
atomic_inc(&eb->refs);
reads_done = atomic_dec_and_test(&eb->io_pages);
if (!reads_done)
goto err;
eb->read_mirror = mirror;
if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) {
ret = -EIO;
goto err;
}
ret = validate_extent_buffer(eb, &bbio->parent_check);
err:
if (ret) {
/*
* our io error hook is going to dec the io pages
* again, we have to make sure it has something
* to decrement
*/
atomic_inc(&eb->io_pages);
clear_extent_buffer_uptodate(eb);
}
free_extent_buffer(eb);
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)
{
struct btrfs_fs_info *fs_info;
int ret;
if (wbc->sync_mode == WB_SYNC_NONE) {
if (wbc->for_kupdate)
return 0;
fs_info = BTRFS_I(mapping->host)->root->fs_info;
/* this is a bit racy, but that's ok */
ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
BTRFS_DIRTY_METADATA_THRESH,
fs_info->dirty_metadata_batch);
if (ret < 0)
return 0;
}
return btree_write_cache_pages(mapping, wbc);
}
static 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 = &BTRFS_I(folio->mapping->host)->io_tree;
extent_invalidate_folio(tree, folio, offset);
btree_release_folio(folio, GFP_NOFS);
if (folio_get_private(folio)) {
btrfs_warn(BTRFS_I(folio->mapping->host)->root->fs_info,
"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 = btrfs_sb(mapping->host->i_sb);
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);
}
subpage = folio_get_private(folio);
ASSERT(subpage->dirty_bitmap);
while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) {
unsigned long flags;
u64 cur;
u16 tmp = (1 << cur_bit);
spin_lock_irqsave(&subpage->lock, flags);
if (!(tmp & subpage->dirty_bitmap)) {
spin_unlock_irqrestore(&subpage->lock, flags);
cur_bit++;
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);
}
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);
}
if (btrfs_check_eb_owner(buf, check->owner_root)) {
free_extent_buffer_stale(buf);
return ERR_PTR(-EUCLEAN);
}
return buf;
}
static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
u64 objectid)
{
bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
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);
root->last_trans = 0;
root->free_objectid = 0;
root->nr_delalloc_inodes = 0;
root->nr_ordered_extents = 0;
root->inode_tree = RB_ROOT;
INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
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);
INIT_LIST_HEAD(&root->logged_list[0]);
INIT_LIST_HEAD(&root->logged_list[1]);
spin_lock_init(&root->inode_lock);
spin_lock_init(&root->delalloc_lock);
spin_lock_init(&root->ordered_extent_lock);
spin_lock_init(&root->accounting_lock);
spin_lock_init(&root->log_extents_lock[0]);
spin_lock_init(&root->log_extents_lock[1]);
spin_lock_init(&root->qgroup_meta_rsv_lock);
mutex_init(&root->objectid_mutex);
mutex_init(&root->log_mutex);
mutex_init(&root->ordered_extent_mutex);
mutex_init(&root->delalloc_mutex);
init_waitqueue_head(&root->qgroup_flush_wait);
init_waitqueue_head(&root->log_writer_wait);
init_waitqueue_head(&root->log_commit_wait[0]);
init_waitqueue_head(&root->log_commit_wait[1]);
INIT_LIST_HEAD(&root->log_ctxs[0]);
INIT_LIST_HEAD(&root->log_ctxs[1]);
atomic_set(&root->log_commit[0], 0);
atomic_set(&root->log_commit[1], 0);
atomic_set(&root->log_writers, 0);
atomic_set(&root->log_batch, 0);
refcount_set(&root->refs, 1);
atomic_set(&root->snapshot_force_cow, 0);
atomic_set(&root->nr_swapfiles, 0);
root->log_transid = 0;
root->log_transid_committed = -1;
root->last_log_commit = 0;
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;
write_lock(&fs_info->global_root_lock);
tmp = rb_find_add(&root->rb_node, &fs_info->global_root_tree, global_root_cmp);