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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 "volumes.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"
#define BTRFS_SUPER_FLAG_SUPP (BTRFS_HEADER_FLAG_WRITTEN |\
BTRFS_HEADER_FLAG_RELOC |\
BTRFS_SUPER_FLAG_ERROR |\
BTRFS_SUPER_FLAG_SEEDING |\
BTRFS_SUPER_FLAG_METADUMP |\
BTRFS_SUPER_FLAG_METADUMP_V2)
static void end_workqueue_fn(struct btrfs_work *work);
static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
struct btrfs_fs_info *fs_info);
static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
static int btrfs_destroy_marked_extents(struct btrfs_fs_info *fs_info,
struct extent_io_tree *dirty_pages,
int mark);
static int btrfs_destroy_pinned_extent(struct btrfs_fs_info *fs_info,
struct extent_io_tree *pinned_extents);
static int btrfs_cleanup_transaction(struct btrfs_fs_info *fs_info);
static void btrfs_error_commit_super(struct btrfs_fs_info *fs_info);
/*
* btrfs_end_io_wq structs are used to do processing in task context when an IO
* is complete. This is used during reads to verify checksums, and it is used
* by writes to insert metadata for new file extents after IO is complete.
*/
struct btrfs_end_io_wq {
struct bio *bio;
bio_end_io_t *end_io;
void *private;
struct btrfs_fs_info *info;
blk_status_t status;
enum btrfs_wq_endio_type metadata;
struct btrfs_work work;
};
static struct kmem_cache *btrfs_end_io_wq_cache;
int __init btrfs_end_io_wq_init(void)
{
btrfs_end_io_wq_cache = kmem_cache_create("btrfs_end_io_wq",
sizeof(struct btrfs_end_io_wq),
0,
SLAB_MEM_SPREAD,
NULL);
if (!btrfs_end_io_wq_cache)
return -ENOMEM;
return 0;
}
void __cold btrfs_end_io_wq_exit(void)
{
kmem_cache_destroy(btrfs_end_io_wq_cache);
}
static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
{
if (fs_info->csum_shash)
crypto_free_shash(fs_info->csum_shash);
}
/*
* async submit bios are used to offload expensive checksumming
* onto the worker threads. They checksum file and metadata bios
* just before they are sent down the IO stack.
*/
struct async_submit_bio {
struct inode *inode;
struct bio *bio;
extent_submit_bio_start_t *submit_bio_start;
int mirror_num;
/* Optional parameter for submit_bio_start used by direct io */
u64 dio_file_offset;
struct btrfs_work work;
blk_status_t status;
};
/*
* Lockdep class keys for extent_buffer->lock's in this root. For a given
* eb, the lockdep key is determined by the btrfs_root it belongs to and
* the level the eb occupies in the tree.
*
* Different roots are used for different purposes and may nest inside each
* other and they require separate keysets. As lockdep keys should be
* static, assign keysets according to the purpose of the root as indicated
* by btrfs_root->root_key.objectid. This ensures that all special purpose
* roots have separate keysets.
*
* Lock-nesting across peer nodes is always done with the immediate parent
* node locked thus preventing deadlock. As lockdep doesn't know this, use
* subclass to avoid triggering lockdep warning in such cases.
*
* The key is set by the readpage_end_io_hook after the buffer has passed
* csum validation but before the pages are unlocked. It is also set by
* btrfs_init_new_buffer on freshly allocated blocks.
*
* We also add a check to make sure the highest level of the tree is the
* same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
* needs update as well.
*/
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# if BTRFS_MAX_LEVEL != 8
# error
# endif
#define DEFINE_LEVEL(stem, level) \
.names[level] = "btrfs-" stem "-0" #level,
#define DEFINE_NAME(stem) \
DEFINE_LEVEL(stem, 0) \
DEFINE_LEVEL(stem, 1) \
DEFINE_LEVEL(stem, 2) \
DEFINE_LEVEL(stem, 3) \
DEFINE_LEVEL(stem, 4) \
DEFINE_LEVEL(stem, 5) \
DEFINE_LEVEL(stem, 6) \
DEFINE_LEVEL(stem, 7)
static struct btrfs_lockdep_keyset {
u64 id; /* root objectid */
/* Longest entry: btrfs-free-space-00 */
char names[BTRFS_MAX_LEVEL][20];
struct lock_class_key keys[BTRFS_MAX_LEVEL];
} btrfs_lockdep_keysets[] = {
{ .id = BTRFS_ROOT_TREE_OBJECTID, DEFINE_NAME("root") },
{ .id = BTRFS_EXTENT_TREE_OBJECTID, DEFINE_NAME("extent") },
{ .id = BTRFS_CHUNK_TREE_OBJECTID, DEFINE_NAME("chunk") },
{ .id = BTRFS_DEV_TREE_OBJECTID, DEFINE_NAME("dev") },
{ .id = BTRFS_CSUM_TREE_OBJECTID, DEFINE_NAME("csum") },
{ .id = BTRFS_QUOTA_TREE_OBJECTID, DEFINE_NAME("quota") },
{ .id = BTRFS_TREE_LOG_OBJECTID, DEFINE_NAME("log") },
{ .id = BTRFS_TREE_RELOC_OBJECTID, DEFINE_NAME("treloc") },
{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID, DEFINE_NAME("dreloc") },
{ .id = BTRFS_UUID_TREE_OBJECTID, DEFINE_NAME("uuid") },
{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID, DEFINE_NAME("free-space") },
{ .id = 0, DEFINE_NAME("tree") },
};
#undef DEFINE_LEVEL
#undef DEFINE_NAME
void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
int level)
{
struct btrfs_lockdep_keyset *ks;
BUG_ON(level >= ARRAY_SIZE(ks->keys));
/* find the matching keyset, id 0 is the default entry */
for (ks = btrfs_lockdep_keysets; ks->id; ks++)
if (ks->id == objectid)
break;
lockdep_set_class_and_name(&eb->lock,
&ks->keys[level], ks->names[level]);
}
#endif
/*
* Compute the csum of a btree block and store the result to provided buffer.
*/
static void csum_tree_block(struct extent_buffer *buf, u8 *result)
{
struct btrfs_fs_info *fs_info = buf->fs_info;
const int num_pages = fs_info->nodesize >> PAGE_SHIFT;
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;
bool need_lock = (current->journal_info == BTRFS_SEND_TRANS_STUB);
if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
return 0;
if (atomic)
return -EAGAIN;
if (need_lock)
btrfs_tree_read_lock(eb);
lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
&cached_state);
if (extent_buffer_uptodate(eb) &&
btrfs_header_generation(eb) == parent_transid) {
ret = 0;
goto out;
}
btrfs_err_rl(eb->fs_info,
"parent transid verify failed on %llu wanted %llu found %llu",
eb->start,
parent_transid, btrfs_header_generation(eb));
ret = 1;
/*
* Things reading via commit roots that don't have normal protection,
* like send, can have a really old block in cache that may point at a
* block that has been freed and re-allocated. So don't clear uptodate
* if we find an eb that is under IO (dirty/writeback) because we could
* end up reading in the stale data and then writing it back out and
* making everybody very sad.
*/
if (!extent_buffer_under_io(eb))
clear_extent_buffer_uptodate(eb);
out:
unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
&cached_state);
if (need_lock)
btrfs_tree_read_unlock(eb);
return ret;
}
static bool btrfs_supported_super_csum(u16 csum_type)
{
switch (csum_type) {
case BTRFS_CSUM_TYPE_CRC32:
case BTRFS_CSUM_TYPE_XXHASH:
case BTRFS_CSUM_TYPE_SHA256:
case BTRFS_CSUM_TYPE_BLAKE2:
return true;
default:
return false;
}
}
/*
* Return 0 if the superblock checksum type matches the checksum value of that
* algorithm. Pass the raw disk superblock data.
*/
static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
char *raw_disk_sb)
{
struct btrfs_super_block *disk_sb =
(struct btrfs_super_block *)raw_disk_sb;
char result[BTRFS_CSUM_SIZE];
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
shash->tfm = fs_info->csum_shash;
/*
* The super_block structure does not span the whole
* BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
* filled with zeros and is included in the checksum.
*/
crypto_shash_digest(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
if (memcmp(disk_sb->csum, result, 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;
}
/*
* helper to read a given tree block, doing retries as required when
* the checksums don't match and we have alternate mirrors to try.
*
* @parent_transid: expected transid, skip check if 0
* @level: expected level, mandatory check
* @first_key: expected key of first slot, skip check if NULL
*/
static int btree_read_extent_buffer_pages(struct extent_buffer *eb,
u64 parent_transid, int level,
struct btrfs_key *first_key)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
struct extent_io_tree *io_tree;
int failed = 0;
int ret;
int num_copies = 0;
int mirror_num = 0;
int failed_mirror = 0;
io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
while (1) {
clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
ret = read_extent_buffer_pages(eb, WAIT_COMPLETE, mirror_num);
if (!ret) {
if (verify_parent_transid(io_tree, eb,
parent_transid, 0))
ret = -EIO;
else if (btrfs_verify_level_key(eb, level,
first_key, parent_transid))
ret = -EUCLEAN;
else
break;
}
num_copies = btrfs_num_copies(fs_info,
eb->start, eb->len);
if (num_copies == 1)
break;
if (!failed_mirror) {
failed = 1;
failed_mirror = eb->read_mirror;
}
mirror_num++;
if (mirror_num == failed_mirror)
mirror_num++;
if (mirror_num > num_copies)
break;
}
if (failed && !ret && failed_mirror)
btrfs_repair_eb_io_failure(eb, failed_mirror);
return ret;
}
/*
* Checksum a dirty tree block before IO. This has extra checks to make sure
* we only fill in the checksum field in the first page of a multi-page block.
* 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;
u8 result[BTRFS_CSUM_SIZE];
struct extent_buffer *eb;
int ret;
eb = (struct extent_buffer *)page->private;
if (page != eb->pages[0])
return 0;
found_start = btrfs_header_bytenr(eb);
/*
* Please do not consolidate these warnings into a single if.
* It is useful to know what went wrong.
*/
if (WARN_ON(found_start != start))
return -EUCLEAN;
if (WARN_ON(!PageUptodate(page)))
return -EUCLEAN;
ASSERT(memcmp_extent_buffer(eb, fs_info->fs_devices->metadata_uuid,
offsetof(struct btrfs_header, fsid),
BTRFS_FSID_SIZE) == 0);
csum_tree_block(eb, result);
if (btrfs_header_level(eb))
ret = btrfs_check_node(eb);
else
ret = btrfs_check_leaf_full(eb);
if (ret < 0) {
btrfs_print_tree(eb, 0);
btrfs_err(fs_info,
"block=%llu write time tree block corruption detected",
eb->start);
WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
return ret;
}
write_extent_buffer(eb, result, 0, fs_info->csum_size);
return 0;
}
static int check_tree_block_fsid(struct extent_buffer *eb)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
u8 fsid[BTRFS_FSID_SIZE];
u8 *metadata_uuid;
read_extent_buffer(eb, fsid, offsetof(struct btrfs_header, fsid),
BTRFS_FSID_SIZE);
/*
* Checking the incompat flag is only valid for the current fs. For
* seed devices it's forbidden to have their uuid changed so reading
* ->fsid in this case is fine
*/
if (btrfs_fs_incompat(fs_info, METADATA_UUID))
metadata_uuid = fs_devices->metadata_uuid;
else
metadata_uuid = fs_devices->fsid;
if (!memcmp(fsid, metadata_uuid, BTRFS_FSID_SIZE))
return 0;
list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list)
if (!memcmp(fsid, seed_devs->fsid, BTRFS_FSID_SIZE))
return 0;
return 1;
}
/* Do basic extent buffer checks at read time */
static int validate_extent_buffer(struct extent_buffer *eb)
{
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];
int ret = 0;
found_start = btrfs_header_bytenr(eb);
if (found_start != eb->start) {
btrfs_err_rl(fs_info, "bad tree block start, want %llu have %llu",
eb->start, found_start);
ret = -EIO;
goto out;
}
if (check_tree_block_fsid(eb)) {
btrfs_err_rl(fs_info, "bad fsid on block %llu",
eb->start);
ret = -EIO;
goto out;
}
found_level = btrfs_header_level(eb);
if (found_level >= BTRFS_MAX_LEVEL) {
btrfs_err(fs_info, "bad tree block level %d on %llu",
(int)btrfs_header_level(eb), eb->start);
ret = -EIO;
goto out;
}
csum_tree_block(eb, result);
if (memcmp_extent_buffer(eb, result, 0, csum_size)) {
u8 val[BTRFS_CSUM_SIZE] = { 0 };
read_extent_buffer(eb, &val, 0, csum_size);
btrfs_warn_rl(fs_info,
"%s checksum verify failed on %llu wanted " CSUM_FMT " found " CSUM_FMT " level %d",
fs_info->sb->s_id, eb->start,
CSUM_FMT_VALUE(csum_size, val),
CSUM_FMT_VALUE(csum_size, result),
btrfs_header_level(eb));
ret = -EUCLEAN;
goto 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,
"block=%llu read time tree block corruption detected",
eb->start);
out:
return ret;
}
int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio,
struct page *page, u64 start, u64 end,
int mirror)
{
struct extent_buffer *eb;
int ret = 0;
int reads_done;
ASSERT(page->private);
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);
err:
if (reads_done &&
test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
btree_readahead_hook(eb, ret);
if (ret) {
/*
* our io error hook is going to dec the io pages
* again, we have to make sure it has something
* to decrement
*/
atomic_inc(&eb->io_pages);
clear_extent_buffer_uptodate(eb);
}
free_extent_buffer(eb);
return ret;
}
static void end_workqueue_bio(struct bio *bio)
{
struct btrfs_end_io_wq *end_io_wq = bio->bi_private;
struct btrfs_fs_info *fs_info;
struct btrfs_workqueue *wq;
fs_info = end_io_wq->info;
end_io_wq->status = bio->bi_status;
if (bio_op(bio) == REQ_OP_WRITE) {
if (end_io_wq->metadata == BTRFS_WQ_ENDIO_METADATA)
wq = fs_info->endio_meta_write_workers;
else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_FREE_SPACE)
wq = fs_info->endio_freespace_worker;
else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
wq = fs_info->endio_raid56_workers;
else
wq = fs_info->endio_write_workers;
} else {
if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
wq = fs_info->endio_raid56_workers;
else if (end_io_wq->metadata)
wq = fs_info->endio_meta_workers;
else
wq = fs_info->endio_workers;
}
btrfs_init_work(&end_io_wq->work, end_workqueue_fn, NULL, NULL);
btrfs_queue_work(wq, &end_io_wq->work);
}
blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
enum btrfs_wq_endio_type metadata)
{
struct btrfs_end_io_wq *end_io_wq;
end_io_wq = kmem_cache_alloc(btrfs_end_io_wq_cache, GFP_NOFS);
if (!end_io_wq)
return BLK_STS_RESOURCE;
end_io_wq->private = bio->bi_private;
end_io_wq->end_io = bio->bi_end_io;
end_io_wq->info = info;
end_io_wq->status = 0;
end_io_wq->bio = bio;
end_io_wq->metadata = metadata;
bio->bi_private = end_io_wq;
bio->bi_end_io = end_workqueue_bio;
return 0;
}
static void run_one_async_start(struct btrfs_work *work)
{
struct async_submit_bio *async;
blk_status_t ret;
async = container_of(work, struct async_submit_bio, work);
ret = async->submit_bio_start(async->inode, async->bio,
async->dio_file_offset);
if (ret)
async->status = ret;
}
/*
* In order to insert checksums into the metadata in large chunks, we wait
* until bio submission time. All the pages in the bio are checksummed and
* sums are attached onto the ordered extent record.
*
* At IO completion time the csums attached on the ordered extent record are
* inserted into the tree.
*/
static void run_one_async_done(struct btrfs_work *work)
{
struct async_submit_bio *async;
struct inode *inode;
blk_status_t ret;
async = container_of(work, struct async_submit_bio, work);
inode = async->inode;
/* If an error occurred we just want to clean up the bio and move on */
if (async->status) {
async->bio->bi_status = async->status;
bio_endio(async->bio);
return;
}
/*
* All of the bios that pass through here are from async helpers.
* Use REQ_CGROUP_PUNT to issue them from the owning cgroup's context.
* This changes nothing when cgroups aren't in use.
*/
async->bio->bi_opf |= REQ_CGROUP_PUNT;
ret = btrfs_map_bio(btrfs_sb(inode->i_sb), async->bio, async->mirror_num);
if (ret) {
async->bio->bi_status = ret;
bio_endio(async->bio);
}
}
static void run_one_async_free(struct btrfs_work *work)
{
struct async_submit_bio *async;
async = container_of(work, struct async_submit_bio, work);
kfree(async);
}
blk_status_t btrfs_wq_submit_bio(struct inode *inode, struct bio *bio,
int mirror_num, unsigned long bio_flags,
u64 dio_file_offset,
extent_submit_bio_start_t *submit_bio_start)
{
struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
struct async_submit_bio *async;
async = kmalloc(sizeof(*async), GFP_NOFS);
if (!async)
return BLK_STS_RESOURCE;
async->inode = inode;
async->bio = bio;
async->mirror_num = mirror_num;
async->submit_bio_start = submit_bio_start;
btrfs_init_work(&async->work, run_one_async_start, run_one_async_done,
run_one_async_free);
async->dio_file_offset = dio_file_offset;
async->status = 0;
if (op_is_sync(bio->bi_opf))
btrfs_set_work_high_priority(&async->work);
btrfs_queue_work(fs_info->workers, &async->work);
return 0;
}
static blk_status_t btree_csum_one_bio(struct bio *bio)
{
struct bio_vec *bvec;
struct btrfs_root *root;
int ret = 0;
struct bvec_iter_all iter_all;
ASSERT(!bio_flagged(bio, BIO_CLONED));
bio_for_each_segment_all(bvec, bio, iter_all) {
root = BTRFS_I(bvec->bv_page->mapping->host)->root;
ret = csum_dirty_buffer(root->fs_info, bvec);
if (ret)
break;
}
return errno_to_blk_status(ret);
}
static blk_status_t btree_submit_bio_start(struct inode *inode, struct bio *bio,
u64 dio_file_offset)
{
/*
* when we're called for a write, we're already in the async
* submission context. Just jump into btrfs_map_bio
*/
return btree_csum_one_bio(bio);
}
static int check_async_write(struct btrfs_fs_info *fs_info,
struct btrfs_inode *bi)
{
if (atomic_read(&bi->sync_writers))
return 0;
if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
return 0;
return 1;
}
blk_status_t btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio,
int mirror_num, unsigned long bio_flags)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
int async = check_async_write(fs_info, BTRFS_I(inode));
blk_status_t ret;
if (bio_op(bio) != REQ_OP_WRITE) {
/*
* called for a read, do the setup so that checksum validation
* can happen in the async kernel threads
*/
ret = btrfs_bio_wq_end_io(fs_info, bio,
BTRFS_WQ_ENDIO_METADATA);
if (ret)
goto out_w_error;
ret = btrfs_map_bio(fs_info, bio, mirror_num);
} else if (!async) {
ret = btree_csum_one_bio(bio);
if (ret)
goto out_w_error;
ret = btrfs_map_bio(fs_info, bio, mirror_num);
} else {
/*
* kthread helpers are used to submit writes so that
* checksumming can happen in parallel across all CPUs
*/
ret = btrfs_wq_submit_bio(inode, bio, mirror_num, 0,
0, btree_submit_bio_start);
}
if (ret)
goto out_w_error;
return 0;
out_w_error:
bio->bi_status = ret;
bio_endio(bio);
return ret;
}
#ifdef CONFIG_MIGRATION
static int btree_migratepage(struct address_space *mapping,
struct page *newpage, struct page *page,
enum migrate_mode mode)
{
/*
* we can't safely write a btree page from here,
* we haven't done the locking hook
*/
if (PageDirty(page))
return -EAGAIN;
/*
* Buffers may be managed in a filesystem specific way.
* We must have no buffers or drop them.
*/
if (page_has_private(page) &&
!try_to_release_page(page, GFP_KERNEL))
return -EAGAIN;
return migrate_page(mapping, newpage, page, mode);
}
#endif
static int btree_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
struct btrfs_fs_info *fs_info;
int ret;
if (wbc->sync_mode == WB_SYNC_NONE) {
if (wbc->for_kupdate)
return 0;
fs_info = BTRFS_I(mapping->host)->root->fs_info;
/* this is a bit racy, but that's ok */
ret = __percpu_counter_compare(&fs_info->dirty_metadata_bytes,
BTRFS_DIRTY_METADATA_THRESH,
fs_info->dirty_metadata_batch);
if (ret < 0)
return 0;
}
return btree_write_cache_pages(mapping, wbc);
}
static int btree_releasepage(struct page *page, gfp_t gfp_flags)
{
if (PageWriteback(page) || PageDirty(page))
return 0;
return try_release_extent_buffer(page);
}
static void btree_invalidatepage(struct page *page, unsigned int offset,
unsigned int length)
{
struct extent_io_tree *tree;
tree = &BTRFS_I(page->mapping->host)->io_tree;
extent_invalidatepage(tree, page, offset);
btree_releasepage(page, GFP_NOFS);
if (PagePrivate(page)) {
btrfs_warn(BTRFS_I(page->mapping->host)->root->fs_info,
"page private not zero on page %llu",
(unsigned long long)page_offset(page));
detach_page_private(page);
}
}
static int btree_set_page_dirty(struct page *page)
{
#ifdef DEBUG
struct extent_buffer *eb;
BUG_ON(!PagePrivate(page));
eb = (struct extent_buffer *)page->private;
BUG_ON(!eb);
BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
BUG_ON(!atomic_read(&eb->refs));
btrfs_assert_tree_locked(eb);
#endif
return __set_page_dirty_nobuffers(page);
}
static const struct address_space_operations btree_aops = {
.writepages = btree_writepages,
.releasepage = btree_releasepage,
.invalidatepage = btree_invalidatepage,
#ifdef CONFIG_MIGRATION
.migratepage = btree_migratepage,
#endif
.set_page_dirty = btree_set_page_dirty,
};
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.
*
* @owner_root: the objectid of the root owner for this block.
* @parent_transid: expected transid of this tree block, skip check if 0
* @level: expected level, mandatory check
* @first_key: expected key in slot 0, skip check if NULL
*/
struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
u64 owner_root, u64 parent_transid,
int level, struct btrfs_key *first_key)
{
struct extent_buffer *buf = NULL;
int ret;
buf = btrfs_find_create_tree_block(fs_info, bytenr, owner_root, level);
if (IS_ERR(buf))
return buf;
ret = btree_read_extent_buffer_pages(buf, parent_transid,
level, first_key);
if (ret) {
free_extent_buffer_stale(buf);
return ERR_PTR(ret);
}
return buf;
}
void btrfs_clean_tree_block(struct extent_buffer *buf)
{
struct btrfs_fs_info *fs_info = buf->fs_info;
if (btrfs_header_generation(buf) ==
fs_info->running_transaction->transid) {
btrfs_assert_tree_locked(buf);
if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
percpu_counter_add_batch(&fs_info->dirty_metadata_bytes,