linux/fs/bcachefs/backpointers.c
Kent Overstreet 8528bde1b6 bcachefs: Fix uninitialized var warning
Can't actually be used uninitialized, but gcc was being silly.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-05-28 18:21:51 -04:00

1011 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "bbpos.h"
#include "alloc_background.h"
#include "backpointers.h"
#include "bkey_buf.h"
#include "btree_cache.h"
#include "btree_update.h"
#include "btree_update_interior.h"
#include "btree_write_buffer.h"
#include "checksum.h"
#include "error.h"
#include <linux/mm.h>
static bool extent_matches_bp(struct bch_fs *c,
enum btree_id btree_id, unsigned level,
struct bkey_s_c k,
struct bpos bucket,
struct bch_backpointer bp)
{
struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
const union bch_extent_entry *entry;
struct extent_ptr_decoded p;
rcu_read_lock();
bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
struct bpos bucket2;
struct bch_backpointer bp2;
if (p.ptr.cached)
continue;
struct bch_dev *ca = bch2_dev_rcu(c, p.ptr.dev);
if (!ca)
continue;
bch2_extent_ptr_to_bp(c, ca, btree_id, level, k, p, entry, &bucket2, &bp2);
if (bpos_eq(bucket, bucket2) &&
!memcmp(&bp, &bp2, sizeof(bp))) {
rcu_read_unlock();
return true;
}
}
rcu_read_unlock();
return false;
}
int bch2_backpointer_invalid(struct bch_fs *c, struct bkey_s_c k,
enum bch_validate_flags flags,
struct printbuf *err)
{
struct bkey_s_c_backpointer bp = bkey_s_c_to_backpointer(k);
rcu_read_lock();
struct bch_dev *ca = bch2_dev_rcu(c, bp.k->p.inode);
if (!ca) {
/* these will be caught by fsck */
rcu_read_unlock();
return 0;
}
struct bpos bucket = bp_pos_to_bucket(ca, bp.k->p);
struct bpos bp_pos = bucket_pos_to_bp_noerror(ca, bucket, bp.v->bucket_offset);
rcu_read_unlock();
int ret = 0;
bkey_fsck_err_on((bp.v->bucket_offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT) >= ca->mi.bucket_size ||
!bpos_eq(bp.k->p, bp_pos),
c, err,
backpointer_bucket_offset_wrong,
"backpointer bucket_offset wrong");
fsck_err:
return ret;
}
void bch2_backpointer_to_text(struct printbuf *out, const struct bch_backpointer *bp)
{
prt_printf(out, "btree=%s l=%u offset=%llu:%u len=%u pos=",
bch2_btree_id_str(bp->btree_id),
bp->level,
(u64) (bp->bucket_offset >> MAX_EXTENT_COMPRESS_RATIO_SHIFT),
(u32) bp->bucket_offset & ~(~0U << MAX_EXTENT_COMPRESS_RATIO_SHIFT),
bp->bucket_len);
bch2_bpos_to_text(out, bp->pos);
}
void bch2_backpointer_k_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
{
rcu_read_lock();
struct bch_dev *ca = bch2_dev_rcu(c, k.k->p.inode);
if (ca) {
struct bpos bucket = bp_pos_to_bucket(ca, k.k->p);
rcu_read_unlock();
prt_str(out, "bucket=");
bch2_bpos_to_text(out, bucket);
prt_str(out, " ");
} else {
rcu_read_unlock();
}
bch2_backpointer_to_text(out, bkey_s_c_to_backpointer(k).v);
}
void bch2_backpointer_swab(struct bkey_s k)
{
struct bkey_s_backpointer bp = bkey_s_to_backpointer(k);
bp.v->bucket_offset = swab40(bp.v->bucket_offset);
bp.v->bucket_len = swab32(bp.v->bucket_len);
bch2_bpos_swab(&bp.v->pos);
}
static noinline int backpointer_mod_err(struct btree_trans *trans,
struct bch_backpointer bp,
struct bkey_s_c bp_k,
struct bkey_s_c orig_k,
bool insert)
{
struct bch_fs *c = trans->c;
struct printbuf buf = PRINTBUF;
if (insert) {
prt_printf(&buf, "existing backpointer found when inserting ");
bch2_backpointer_to_text(&buf, &bp);
prt_newline(&buf);
printbuf_indent_add(&buf, 2);
prt_printf(&buf, "found ");
bch2_bkey_val_to_text(&buf, c, bp_k);
prt_newline(&buf);
prt_printf(&buf, "for ");
bch2_bkey_val_to_text(&buf, c, orig_k);
bch_err(c, "%s", buf.buf);
} else if (c->curr_recovery_pass > BCH_RECOVERY_PASS_check_extents_to_backpointers) {
prt_printf(&buf, "backpointer not found when deleting\n");
printbuf_indent_add(&buf, 2);
prt_printf(&buf, "searching for ");
bch2_backpointer_to_text(&buf, &bp);
prt_newline(&buf);
prt_printf(&buf, "got ");
bch2_bkey_val_to_text(&buf, c, bp_k);
prt_newline(&buf);
prt_printf(&buf, "for ");
bch2_bkey_val_to_text(&buf, c, orig_k);
bch_err(c, "%s", buf.buf);
}
printbuf_exit(&buf);
if (c->curr_recovery_pass > BCH_RECOVERY_PASS_check_extents_to_backpointers) {
return bch2_inconsistent_error(c) ? BCH_ERR_erofs_unfixed_errors : 0;
} else {
return 0;
}
}
int bch2_bucket_backpointer_mod_nowritebuffer(struct btree_trans *trans,
struct bch_dev *ca,
struct bpos bucket,
struct bch_backpointer bp,
struct bkey_s_c orig_k,
bool insert)
{
struct btree_iter bp_iter;
struct bkey_s_c k;
struct bkey_i_backpointer *bp_k;
int ret;
bp_k = bch2_trans_kmalloc_nomemzero(trans, sizeof(struct bkey_i_backpointer));
ret = PTR_ERR_OR_ZERO(bp_k);
if (ret)
return ret;
bkey_backpointer_init(&bp_k->k_i);
bp_k->k.p = bucket_pos_to_bp(ca, bucket, bp.bucket_offset);
bp_k->v = bp;
if (!insert) {
bp_k->k.type = KEY_TYPE_deleted;
set_bkey_val_u64s(&bp_k->k, 0);
}
k = bch2_bkey_get_iter(trans, &bp_iter, BTREE_ID_backpointers,
bp_k->k.p,
BTREE_ITER_intent|
BTREE_ITER_slots|
BTREE_ITER_with_updates);
ret = bkey_err(k);
if (ret)
goto err;
if (insert
? k.k->type
: (k.k->type != KEY_TYPE_backpointer ||
memcmp(bkey_s_c_to_backpointer(k).v, &bp, sizeof(bp)))) {
ret = backpointer_mod_err(trans, bp, k, orig_k, insert);
if (ret)
goto err;
}
ret = bch2_trans_update(trans, &bp_iter, &bp_k->k_i, 0);
err:
bch2_trans_iter_exit(trans, &bp_iter);
return ret;
}
/*
* Find the next backpointer >= *bp_offset:
*/
int bch2_get_next_backpointer(struct btree_trans *trans,
struct bch_dev *ca,
struct bpos bucket, int gen,
struct bpos *bp_pos,
struct bch_backpointer *bp,
unsigned iter_flags)
{
struct bpos bp_end_pos = bucket_pos_to_bp(ca, bpos_nosnap_successor(bucket), 0);
struct btree_iter alloc_iter = { NULL }, bp_iter = { NULL };
struct bkey_s_c k;
int ret = 0;
if (bpos_ge(*bp_pos, bp_end_pos))
goto done;
if (gen >= 0) {
k = bch2_bkey_get_iter(trans, &alloc_iter, BTREE_ID_alloc,
bucket, BTREE_ITER_cached|iter_flags);
ret = bkey_err(k);
if (ret)
goto out;
if (k.k->type != KEY_TYPE_alloc_v4 ||
bkey_s_c_to_alloc_v4(k).v->gen != gen)
goto done;
}
*bp_pos = bpos_max(*bp_pos, bucket_pos_to_bp(ca, bucket, 0));
for_each_btree_key_norestart(trans, bp_iter, BTREE_ID_backpointers,
*bp_pos, iter_flags, k, ret) {
if (bpos_ge(k.k->p, bp_end_pos))
break;
*bp_pos = k.k->p;
*bp = *bkey_s_c_to_backpointer(k).v;
goto out;
}
done:
*bp_pos = SPOS_MAX;
out:
bch2_trans_iter_exit(trans, &bp_iter);
bch2_trans_iter_exit(trans, &alloc_iter);
return ret;
}
static void backpointer_not_found(struct btree_trans *trans,
struct bpos bp_pos,
struct bch_backpointer bp,
struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct printbuf buf = PRINTBUF;
/*
* If we're using the btree write buffer, the backpointer we were
* looking at may have already been deleted - failure to find what it
* pointed to is not an error:
*/
if (likely(!bch2_backpointers_no_use_write_buffer))
return;
struct bpos bucket;
if (!bp_pos_to_bucket_nodev(c, bp_pos, &bucket))
return;
prt_printf(&buf, "backpointer doesn't match %s it points to:\n ",
bp.level ? "btree node" : "extent");
prt_printf(&buf, "bucket: ");
bch2_bpos_to_text(&buf, bucket);
prt_printf(&buf, "\n ");
prt_printf(&buf, "backpointer pos: ");
bch2_bpos_to_text(&buf, bp_pos);
prt_printf(&buf, "\n ");
bch2_backpointer_to_text(&buf, &bp);
prt_printf(&buf, "\n ");
bch2_bkey_val_to_text(&buf, c, k);
if (c->curr_recovery_pass >= BCH_RECOVERY_PASS_check_extents_to_backpointers)
bch_err_ratelimited(c, "%s", buf.buf);
else
bch2_trans_inconsistent(trans, "%s", buf.buf);
printbuf_exit(&buf);
}
struct bkey_s_c bch2_backpointer_get_key(struct btree_trans *trans,
struct btree_iter *iter,
struct bpos bp_pos,
struct bch_backpointer bp,
unsigned iter_flags)
{
if (likely(!bp.level)) {
struct bch_fs *c = trans->c;
struct bpos bucket;
if (!bp_pos_to_bucket_nodev(c, bp_pos, &bucket))
return bkey_s_c_err(-EIO);
bch2_trans_node_iter_init(trans, iter,
bp.btree_id,
bp.pos,
0, 0,
iter_flags);
struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
if (bkey_err(k)) {
bch2_trans_iter_exit(trans, iter);
return k;
}
if (k.k && extent_matches_bp(c, bp.btree_id, bp.level, k, bucket, bp))
return k;
bch2_trans_iter_exit(trans, iter);
backpointer_not_found(trans, bp_pos, bp, k);
return bkey_s_c_null;
} else {
struct btree *b = bch2_backpointer_get_node(trans, iter, bp_pos, bp);
if (IS_ERR_OR_NULL(b)) {
bch2_trans_iter_exit(trans, iter);
return IS_ERR(b) ? bkey_s_c_err(PTR_ERR(b)) : bkey_s_c_null;
}
return bkey_i_to_s_c(&b->key);
}
}
struct btree *bch2_backpointer_get_node(struct btree_trans *trans,
struct btree_iter *iter,
struct bpos bp_pos,
struct bch_backpointer bp)
{
struct bch_fs *c = trans->c;
BUG_ON(!bp.level);
struct bpos bucket;
if (!bp_pos_to_bucket_nodev(c, bp_pos, &bucket))
return ERR_PTR(-EIO);
bch2_trans_node_iter_init(trans, iter,
bp.btree_id,
bp.pos,
0,
bp.level - 1,
0);
struct btree *b = bch2_btree_iter_peek_node(iter);
if (IS_ERR_OR_NULL(b))
goto err;
BUG_ON(b->c.level != bp.level - 1);
if (extent_matches_bp(c, bp.btree_id, bp.level,
bkey_i_to_s_c(&b->key),
bucket, bp))
return b;
if (btree_node_will_make_reachable(b)) {
b = ERR_PTR(-BCH_ERR_backpointer_to_overwritten_btree_node);
} else {
backpointer_not_found(trans, bp_pos, bp, bkey_i_to_s_c(&b->key));
b = NULL;
}
err:
bch2_trans_iter_exit(trans, iter);
return b;
}
static int bch2_check_btree_backpointer(struct btree_trans *trans, struct btree_iter *bp_iter,
struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct btree_iter alloc_iter = { NULL };
struct bkey_s_c alloc_k;
struct printbuf buf = PRINTBUF;
int ret = 0;
struct bpos bucket;
if (!bp_pos_to_bucket_nodev_noerror(c, k.k->p, &bucket)) {
if (fsck_err(c, backpointer_to_missing_device,
"backpointer for missing device:\n%s",
(bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
ret = bch2_btree_delete_at(trans, bp_iter, 0);
goto out;
}
alloc_k = bch2_bkey_get_iter(trans, &alloc_iter, BTREE_ID_alloc, bucket, 0);
ret = bkey_err(alloc_k);
if (ret)
goto out;
if (fsck_err_on(alloc_k.k->type != KEY_TYPE_alloc_v4, c,
backpointer_to_missing_alloc,
"backpointer for nonexistent alloc key: %llu:%llu:0\n%s",
alloc_iter.pos.inode, alloc_iter.pos.offset,
(bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
ret = bch2_btree_delete_at(trans, bp_iter, 0);
goto out;
}
out:
fsck_err:
bch2_trans_iter_exit(trans, &alloc_iter);
printbuf_exit(&buf);
return ret;
}
/* verify that every backpointer has a corresponding alloc key */
int bch2_check_btree_backpointers(struct bch_fs *c)
{
int ret = bch2_trans_run(c,
for_each_btree_key_commit(trans, iter,
BTREE_ID_backpointers, POS_MIN, 0, k,
NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
bch2_check_btree_backpointer(trans, &iter, k)));
bch_err_fn(c, ret);
return ret;
}
static inline bool bkey_and_val_eq(struct bkey_s_c l, struct bkey_s_c r)
{
return bpos_eq(l.k->p, r.k->p) &&
bkey_bytes(l.k) == bkey_bytes(r.k) &&
!memcmp(l.v, r.v, bkey_val_bytes(l.k));
}
struct extents_to_bp_state {
struct bpos bucket_start;
struct bpos bucket_end;
struct bkey_buf last_flushed;
};
static int drop_dev_and_update(struct btree_trans *trans, enum btree_id btree,
struct bkey_s_c extent, unsigned dev)
{
struct bkey_i *n = bch2_bkey_make_mut_noupdate(trans, extent);
int ret = PTR_ERR_OR_ZERO(n);
if (ret)
return ret;
bch2_bkey_drop_device(bkey_i_to_s(n), dev);
return bch2_btree_insert_trans(trans, btree, n, 0);
}
static int check_extent_checksum(struct btree_trans *trans,
enum btree_id btree, struct bkey_s_c extent,
enum btree_id o_btree, struct bkey_s_c extent2, unsigned dev)
{
struct bch_fs *c = trans->c;
struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(extent);
const union bch_extent_entry *entry;
struct extent_ptr_decoded p;
struct printbuf buf = PRINTBUF;
void *data_buf = NULL;
struct bio *bio = NULL;
size_t bytes;
int ret = 0;
if (bkey_is_btree_ptr(extent.k))
return false;
bkey_for_each_ptr_decode(extent.k, ptrs, p, entry)
if (p.ptr.dev == dev)
goto found;
BUG();
found:
if (!p.crc.csum_type)
return false;
bytes = p.crc.compressed_size << 9;
struct bch_dev *ca = bch2_dev_get_ioref(c, dev, READ);
if (!ca)
return false;
data_buf = kvmalloc(bytes, GFP_KERNEL);
if (!data_buf) {
ret = -ENOMEM;
goto err;
}
bio = bio_alloc(ca->disk_sb.bdev, buf_pages(data_buf, bytes), REQ_OP_READ, GFP_KERNEL);
bio->bi_iter.bi_sector = p.ptr.offset;
bch2_bio_map(bio, data_buf, bytes);
ret = submit_bio_wait(bio);
if (ret)
goto err;
prt_str(&buf, "extents pointing to same space, but first extent checksum bad:");
prt_printf(&buf, "\n %s ", bch2_btree_id_str(btree));
bch2_bkey_val_to_text(&buf, c, extent);
prt_printf(&buf, "\n %s ", bch2_btree_id_str(o_btree));
bch2_bkey_val_to_text(&buf, c, extent2);
struct nonce nonce = extent_nonce(extent.k->version, p.crc);
struct bch_csum csum = bch2_checksum(c, p.crc.csum_type, nonce, data_buf, bytes);
if (fsck_err_on(bch2_crc_cmp(csum, p.crc.csum),
c, dup_backpointer_to_bad_csum_extent,
"%s", buf.buf))
ret = drop_dev_and_update(trans, btree, extent, dev) ?: 1;
fsck_err:
err:
if (bio)
bio_put(bio);
kvfree(data_buf);
percpu_ref_put(&ca->io_ref);
printbuf_exit(&buf);
return ret;
}
static int check_bp_exists(struct btree_trans *trans,
struct extents_to_bp_state *s,
struct bpos bucket,
struct bch_backpointer bp,
struct bkey_s_c orig_k)
{
struct bch_fs *c = trans->c;
struct btree_iter bp_iter = {};
struct btree_iter other_extent_iter = {};
struct printbuf buf = PRINTBUF;
struct bkey_s_c bp_k;
struct bkey_buf tmp;
int ret = 0;
bch2_bkey_buf_init(&tmp);
struct bch_dev *ca = bch2_dev_bucket_tryget(c, bucket);
if (!ca) {
prt_str(&buf, "extent for nonexistent device:bucket ");
bch2_bpos_to_text(&buf, bucket);
prt_str(&buf, "\n ");
bch2_bkey_val_to_text(&buf, c, orig_k);
bch_err(c, "%s", buf.buf);
ret = -BCH_ERR_fsck_repair_unimplemented;
goto err;
}
if (bpos_lt(bucket, s->bucket_start) ||
bpos_gt(bucket, s->bucket_end))
goto out;
bp_k = bch2_bkey_get_iter(trans, &bp_iter, BTREE_ID_backpointers,
bucket_pos_to_bp(ca, bucket, bp.bucket_offset),
0);
ret = bkey_err(bp_k);
if (ret)
goto err;
if (bp_k.k->type != KEY_TYPE_backpointer ||
memcmp(bkey_s_c_to_backpointer(bp_k).v, &bp, sizeof(bp))) {
bch2_bkey_buf_reassemble(&tmp, c, orig_k);
if (!bkey_and_val_eq(orig_k, bkey_i_to_s_c(s->last_flushed.k))) {
if (bp.level) {
bch2_trans_unlock(trans);
bch2_btree_interior_updates_flush(c);
}
ret = bch2_btree_write_buffer_flush_sync(trans);
if (ret)
goto err;
bch2_bkey_buf_copy(&s->last_flushed, c, tmp.k);
ret = -BCH_ERR_transaction_restart_write_buffer_flush;
goto out;
}
goto check_existing_bp;
}
out:
err:
fsck_err:
bch2_trans_iter_exit(trans, &other_extent_iter);
bch2_trans_iter_exit(trans, &bp_iter);
bch2_bkey_buf_exit(&tmp, c);
bch2_dev_put(ca);
printbuf_exit(&buf);
return ret;
check_existing_bp:
/* Do we have a backpointer for a different extent? */
if (bp_k.k->type != KEY_TYPE_backpointer)
goto missing;
struct bch_backpointer other_bp = *bkey_s_c_to_backpointer(bp_k).v;
struct bkey_s_c other_extent =
bch2_backpointer_get_key(trans, &other_extent_iter, bp_k.k->p, other_bp, 0);
ret = bkey_err(other_extent);
if (ret == -BCH_ERR_backpointer_to_overwritten_btree_node)
ret = 0;
if (ret)
goto err;
if (!other_extent.k)
goto missing;
if (bch2_extents_match(orig_k, other_extent)) {
printbuf_reset(&buf);
prt_printf(&buf, "duplicate versions of same extent, deleting smaller\n ");
bch2_bkey_val_to_text(&buf, c, orig_k);
prt_str(&buf, "\n ");
bch2_bkey_val_to_text(&buf, c, other_extent);
bch_err(c, "%s", buf.buf);
if (other_extent.k->size <= orig_k.k->size) {
ret = drop_dev_and_update(trans, other_bp.btree_id, other_extent, bucket.inode);
if (ret)
goto err;
goto out;
} else {
ret = drop_dev_and_update(trans, bp.btree_id, orig_k, bucket.inode);
if (ret)
goto err;
goto missing;
}
}
ret = check_extent_checksum(trans, other_bp.btree_id, other_extent, bp.btree_id, orig_k, bucket.inode);
if (ret < 0)
goto err;
if (ret) {
ret = 0;
goto missing;
}
ret = check_extent_checksum(trans, bp.btree_id, orig_k, other_bp.btree_id, other_extent, bucket.inode);
if (ret < 0)
goto err;
if (ret) {
ret = 0;
goto out;
}
printbuf_reset(&buf);
prt_printf(&buf, "duplicate extents pointing to same space on dev %llu\n ", bucket.inode);
bch2_bkey_val_to_text(&buf, c, orig_k);
prt_str(&buf, "\n ");
bch2_bkey_val_to_text(&buf, c, other_extent);
bch_err(c, "%s", buf.buf);
ret = -BCH_ERR_fsck_repair_unimplemented;
goto err;
missing:
printbuf_reset(&buf);
prt_printf(&buf, "missing backpointer for btree=%s l=%u ",
bch2_btree_id_str(bp.btree_id), bp.level);
bch2_bkey_val_to_text(&buf, c, orig_k);
prt_printf(&buf, "\n got: ");
bch2_bkey_val_to_text(&buf, c, bp_k);
struct bkey_i_backpointer n_bp_k;
bkey_backpointer_init(&n_bp_k.k_i);
n_bp_k.k.p = bucket_pos_to_bp(ca, bucket, bp.bucket_offset);
n_bp_k.v = bp;
prt_printf(&buf, "\n want: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&n_bp_k.k_i));
if (fsck_err(c, ptr_to_missing_backpointer, "%s", buf.buf))
ret = bch2_bucket_backpointer_mod(trans, ca, bucket, bp, orig_k, true);
goto out;
}
static int check_extent_to_backpointers(struct btree_trans *trans,
struct extents_to_bp_state *s,
enum btree_id btree, unsigned level,
struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct bkey_ptrs_c ptrs;
const union bch_extent_entry *entry;
struct extent_ptr_decoded p;
int ret;
ptrs = bch2_bkey_ptrs_c(k);
bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
struct bpos bucket_pos = POS_MIN;
struct bch_backpointer bp;
if (p.ptr.cached)
continue;
rcu_read_lock();
struct bch_dev *ca = bch2_dev_rcu(c, p.ptr.dev);
if (ca)
bch2_extent_ptr_to_bp(c, ca, btree, level, k, p, entry, &bucket_pos, &bp);
rcu_read_unlock();
if (!ca)
continue;
ret = check_bp_exists(trans, s, bucket_pos, bp, k);
if (ret)
return ret;
}
return 0;
}
static int check_btree_root_to_backpointers(struct btree_trans *trans,
struct extents_to_bp_state *s,
enum btree_id btree_id,
int *level)
{
struct bch_fs *c = trans->c;
struct btree_iter iter;
struct btree *b;
struct bkey_s_c k;
int ret;
retry:
bch2_trans_node_iter_init(trans, &iter, btree_id, POS_MIN,
0, bch2_btree_id_root(c, btree_id)->b->c.level, 0);
b = bch2_btree_iter_peek_node(&iter);
ret = PTR_ERR_OR_ZERO(b);
if (ret)
goto err;
if (b != btree_node_root(c, b)) {
bch2_trans_iter_exit(trans, &iter);
goto retry;
}
*level = b->c.level;
k = bkey_i_to_s_c(&b->key);
ret = check_extent_to_backpointers(trans, s, btree_id, b->c.level + 1, k);
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
static inline struct bbpos bp_to_bbpos(struct bch_backpointer bp)
{
return (struct bbpos) {
.btree = bp.btree_id,
.pos = bp.pos,
};
}
static u64 mem_may_pin_bytes(struct bch_fs *c)
{
struct sysinfo i;
si_meminfo(&i);
u64 mem_bytes = i.totalram * i.mem_unit;
return div_u64(mem_bytes * c->opts.fsck_memory_usage_percent, 100);
}
static size_t btree_nodes_fit_in_ram(struct bch_fs *c)
{
return div_u64(mem_may_pin_bytes(c), c->opts.btree_node_size);
}
static int bch2_get_btree_in_memory_pos(struct btree_trans *trans,
u64 btree_leaf_mask,
u64 btree_interior_mask,
struct bbpos start, struct bbpos *end)
{
struct bch_fs *c = trans->c;
s64 mem_may_pin = mem_may_pin_bytes(c);
int ret = 0;
btree_interior_mask |= btree_leaf_mask;
c->btree_cache.pinned_nodes_leaf_mask = btree_leaf_mask;
c->btree_cache.pinned_nodes_interior_mask = btree_interior_mask;
c->btree_cache.pinned_nodes_start = start;
c->btree_cache.pinned_nodes_end = *end = BBPOS_MAX;
for (enum btree_id btree = start.btree;
btree < BTREE_ID_NR && !ret;
btree++) {
unsigned depth = ((1U << btree) & btree_leaf_mask) ? 0 : 1;
struct btree_iter iter;
struct btree *b;
if (!((1U << btree) & btree_leaf_mask) &&
!((1U << btree) & btree_interior_mask))
continue;
__for_each_btree_node(trans, iter, btree,
btree == start.btree ? start.pos : POS_MIN,
0, depth, BTREE_ITER_prefetch, b, ret) {
mem_may_pin -= btree_buf_bytes(b);
if (mem_may_pin <= 0) {
c->btree_cache.pinned_nodes_end = *end =
BBPOS(btree, b->key.k.p);
bch2_trans_iter_exit(trans, &iter);
return 0;
}
}
bch2_trans_iter_exit(trans, &iter);
}
return ret;
}
static int bch2_check_extents_to_backpointers_pass(struct btree_trans *trans,
struct extents_to_bp_state *s)
{
struct bch_fs *c = trans->c;
int ret = 0;
for (enum btree_id btree_id = 0;
btree_id < btree_id_nr_alive(c);
btree_id++) {
int level, depth = btree_type_has_ptrs(btree_id) ? 0 : 1;
ret = commit_do(trans, NULL, NULL,
BCH_TRANS_COMMIT_no_enospc,
check_btree_root_to_backpointers(trans, s, btree_id, &level));
if (ret)
return ret;
while (level >= depth) {
struct btree_iter iter;
bch2_trans_node_iter_init(trans, &iter, btree_id, POS_MIN, 0, level,
BTREE_ITER_prefetch);
ret = for_each_btree_key_continue(trans, iter, 0, k, ({
check_extent_to_backpointers(trans, s, btree_id, level, k) ?:
bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
}));
if (ret)
return ret;
--level;
}
}
return 0;
}
int bch2_check_extents_to_backpointers(struct bch_fs *c)
{
struct btree_trans *trans = bch2_trans_get(c);
struct extents_to_bp_state s = { .bucket_start = POS_MIN };
int ret;
bch2_bkey_buf_init(&s.last_flushed);
bkey_init(&s.last_flushed.k->k);
while (1) {
struct bbpos end;
ret = bch2_get_btree_in_memory_pos(trans,
BIT_ULL(BTREE_ID_backpointers),
BIT_ULL(BTREE_ID_backpointers),
BBPOS(BTREE_ID_backpointers, s.bucket_start), &end);
if (ret)
break;
s.bucket_end = end.pos;
if ( bpos_eq(s.bucket_start, POS_MIN) &&
!bpos_eq(s.bucket_end, SPOS_MAX))
bch_verbose(c, "%s(): alloc info does not fit in ram, running in multiple passes with %zu nodes per pass",
__func__, btree_nodes_fit_in_ram(c));
if (!bpos_eq(s.bucket_start, POS_MIN) ||
!bpos_eq(s.bucket_end, SPOS_MAX)) {
struct printbuf buf = PRINTBUF;
prt_str(&buf, "check_extents_to_backpointers(): ");
bch2_bpos_to_text(&buf, s.bucket_start);
prt_str(&buf, "-");
bch2_bpos_to_text(&buf, s.bucket_end);
bch_verbose(c, "%s", buf.buf);
printbuf_exit(&buf);
}
ret = bch2_check_extents_to_backpointers_pass(trans, &s);
if (ret || bpos_eq(s.bucket_end, SPOS_MAX))
break;
s.bucket_start = bpos_successor(s.bucket_end);
}
bch2_trans_put(trans);
bch2_bkey_buf_exit(&s.last_flushed, c);
c->btree_cache.pinned_nodes_leaf_mask = 0;
c->btree_cache.pinned_nodes_interior_mask = 0;
bch_err_fn(c, ret);
return ret;
}
static int check_one_backpointer(struct btree_trans *trans,
struct bbpos start,
struct bbpos end,
struct bkey_s_c_backpointer bp,
struct bpos *last_flushed_pos)
{
struct bch_fs *c = trans->c;
struct btree_iter iter;
struct bbpos pos = bp_to_bbpos(*bp.v);
struct bkey_s_c k;
struct printbuf buf = PRINTBUF;
int ret;
if (bbpos_cmp(pos, start) < 0 ||
bbpos_cmp(pos, end) > 0)
return 0;
k = bch2_backpointer_get_key(trans, &iter, bp.k->p, *bp.v, 0);
ret = bkey_err(k);
if (ret == -BCH_ERR_backpointer_to_overwritten_btree_node)
return 0;
if (ret)
return ret;
if (!k.k && !bpos_eq(*last_flushed_pos, bp.k->p)) {
*last_flushed_pos = bp.k->p;
ret = bch2_btree_write_buffer_flush_sync(trans) ?:
-BCH_ERR_transaction_restart_write_buffer_flush;
goto out;
}
if (fsck_err_on(!k.k, c,
backpointer_to_missing_ptr,
"backpointer for missing %s\n %s",
bp.v->level ? "btree node" : "extent",
(bch2_bkey_val_to_text(&buf, c, bp.s_c), buf.buf))) {
ret = bch2_btree_delete_at_buffered(trans, BTREE_ID_backpointers, bp.k->p);
goto out;
}
out:
fsck_err:
bch2_trans_iter_exit(trans, &iter);
printbuf_exit(&buf);
return ret;
}
static int bch2_check_backpointers_to_extents_pass(struct btree_trans *trans,
struct bbpos start,
struct bbpos end)
{
struct bpos last_flushed_pos = SPOS_MAX;
return for_each_btree_key_commit(trans, iter, BTREE_ID_backpointers,
POS_MIN, BTREE_ITER_prefetch, k,
NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
check_one_backpointer(trans, start, end,
bkey_s_c_to_backpointer(k),
&last_flushed_pos));
}
int bch2_check_backpointers_to_extents(struct bch_fs *c)
{
struct btree_trans *trans = bch2_trans_get(c);
struct bbpos start = (struct bbpos) { .btree = 0, .pos = POS_MIN, }, end;
int ret;
while (1) {
ret = bch2_get_btree_in_memory_pos(trans,
(1U << BTREE_ID_extents)|
(1U << BTREE_ID_reflink),
~0,
start, &end);
if (ret)
break;
if (!bbpos_cmp(start, BBPOS_MIN) &&
bbpos_cmp(end, BBPOS_MAX))
bch_verbose(c, "%s(): extents do not fit in ram, running in multiple passes with %zu nodes per pass",
__func__, btree_nodes_fit_in_ram(c));
if (bbpos_cmp(start, BBPOS_MIN) ||
bbpos_cmp(end, BBPOS_MAX)) {
struct printbuf buf = PRINTBUF;
prt_str(&buf, "check_backpointers_to_extents(): ");
bch2_bbpos_to_text(&buf, start);
prt_str(&buf, "-");
bch2_bbpos_to_text(&buf, end);
bch_verbose(c, "%s", buf.buf);
printbuf_exit(&buf);
}
ret = bch2_check_backpointers_to_extents_pass(trans, start, end);
if (ret || !bbpos_cmp(end, BBPOS_MAX))
break;
start = bbpos_successor(end);
}
bch2_trans_put(trans);
c->btree_cache.pinned_nodes_leaf_mask = 0;
c->btree_cache.pinned_nodes_interior_mask = 0;
bch_err_fn(c, ret);
return ret;
}