linux-stable/fs/bcachefs/btree_gc.c
Kent Overstreet 43f5ea4646 bcachefs: Topology repair now uses nodes found by scanning to fill holes
With the new btree node scan code, we can now recover from corrupt btree
roots - simply create a new fake root at depth 1, and then insert all
the leaves we found.

If the root wasn't corrupt but there's corruption elsewhere in the
btree, we can fill in holes as needed with the newest version of a given
node(s) from the scan; we also check if a given btree node is older than
what we found from the scan.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-04-03 14:45:30 -04:00

2052 lines
51 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com>
* Copyright (C) 2014 Datera Inc.
*/
#include "bcachefs.h"
#include "alloc_background.h"
#include "alloc_foreground.h"
#include "backpointers.h"
#include "bkey_methods.h"
#include "bkey_buf.h"
#include "btree_journal_iter.h"
#include "btree_key_cache.h"
#include "btree_locking.h"
#include "btree_node_scan.h"
#include "btree_update_interior.h"
#include "btree_io.h"
#include "btree_gc.h"
#include "buckets.h"
#include "clock.h"
#include "debug.h"
#include "ec.h"
#include "error.h"
#include "extents.h"
#include "journal.h"
#include "keylist.h"
#include "move.h"
#include "recovery_passes.h"
#include "reflink.h"
#include "replicas.h"
#include "super-io.h"
#include "trace.h"
#include <linux/slab.h>
#include <linux/bitops.h>
#include <linux/freezer.h>
#include <linux/kthread.h>
#include <linux/preempt.h>
#include <linux/rcupdate.h>
#include <linux/sched/task.h>
#define DROP_THIS_NODE 10
#define DROP_PREV_NODE 11
#define DID_FILL_FROM_SCAN 12
static struct bkey_s unsafe_bkey_s_c_to_s(struct bkey_s_c k)
{
return (struct bkey_s) {{{
(struct bkey *) k.k,
(struct bch_val *) k.v
}}};
}
static bool should_restart_for_topology_repair(struct bch_fs *c)
{
return c->opts.fix_errors != FSCK_FIX_no &&
!(c->recovery_passes_complete & BIT_ULL(BCH_RECOVERY_PASS_check_topology));
}
static inline void __gc_pos_set(struct bch_fs *c, struct gc_pos new_pos)
{
preempt_disable();
write_seqcount_begin(&c->gc_pos_lock);
c->gc_pos = new_pos;
write_seqcount_end(&c->gc_pos_lock);
preempt_enable();
}
static inline void gc_pos_set(struct bch_fs *c, struct gc_pos new_pos)
{
BUG_ON(gc_pos_cmp(new_pos, c->gc_pos) <= 0);
__gc_pos_set(c, new_pos);
}
static void btree_ptr_to_v2(struct btree *b, struct bkey_i_btree_ptr_v2 *dst)
{
switch (b->key.k.type) {
case KEY_TYPE_btree_ptr: {
struct bkey_i_btree_ptr *src = bkey_i_to_btree_ptr(&b->key);
dst->k.p = src->k.p;
dst->v.mem_ptr = 0;
dst->v.seq = b->data->keys.seq;
dst->v.sectors_written = 0;
dst->v.flags = 0;
dst->v.min_key = b->data->min_key;
set_bkey_val_bytes(&dst->k, sizeof(dst->v) + bkey_val_bytes(&src->k));
memcpy(dst->v.start, src->v.start, bkey_val_bytes(&src->k));
break;
}
case KEY_TYPE_btree_ptr_v2:
bkey_copy(&dst->k_i, &b->key);
break;
default:
BUG();
}
}
static void bch2_btree_node_update_key_early(struct btree_trans *trans,
enum btree_id btree, unsigned level,
struct bkey_s_c old, struct bkey_i *new)
{
struct bch_fs *c = trans->c;
struct btree *b;
struct bkey_buf tmp;
int ret;
bch2_bkey_buf_init(&tmp);
bch2_bkey_buf_reassemble(&tmp, c, old);
b = bch2_btree_node_get_noiter(trans, tmp.k, btree, level, true);
if (!IS_ERR_OR_NULL(b)) {
mutex_lock(&c->btree_cache.lock);
bch2_btree_node_hash_remove(&c->btree_cache, b);
bkey_copy(&b->key, new);
ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
BUG_ON(ret);
mutex_unlock(&c->btree_cache.lock);
six_unlock_read(&b->c.lock);
}
bch2_bkey_buf_exit(&tmp, c);
}
static int set_node_min(struct bch_fs *c, struct btree *b, struct bpos new_min)
{
struct bkey_i_btree_ptr_v2 *new;
int ret;
if (c->opts.verbose) {
struct printbuf buf = PRINTBUF;
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
prt_str(&buf, " -> ");
bch2_bpos_to_text(&buf, new_min);
bch_info(c, "%s(): %s", __func__, buf.buf);
printbuf_exit(&buf);
}
new = kmalloc_array(BKEY_BTREE_PTR_U64s_MAX, sizeof(u64), GFP_KERNEL);
if (!new)
return -BCH_ERR_ENOMEM_gc_repair_key;
btree_ptr_to_v2(b, new);
b->data->min_key = new_min;
new->v.min_key = new_min;
SET_BTREE_PTR_RANGE_UPDATED(&new->v, true);
ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i);
if (ret) {
kfree(new);
return ret;
}
bch2_btree_node_drop_keys_outside_node(b);
bkey_copy(&b->key, &new->k_i);
return 0;
}
static int set_node_max(struct bch_fs *c, struct btree *b, struct bpos new_max)
{
struct bkey_i_btree_ptr_v2 *new;
int ret;
if (c->opts.verbose) {
struct printbuf buf = PRINTBUF;
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
prt_str(&buf, " -> ");
bch2_bpos_to_text(&buf, new_max);
bch_info(c, "%s(): %s", __func__, buf.buf);
printbuf_exit(&buf);
}
ret = bch2_journal_key_delete(c, b->c.btree_id, b->c.level + 1, b->key.k.p);
if (ret)
return ret;
new = kmalloc_array(BKEY_BTREE_PTR_U64s_MAX, sizeof(u64), GFP_KERNEL);
if (!new)
return -BCH_ERR_ENOMEM_gc_repair_key;
btree_ptr_to_v2(b, new);
b->data->max_key = new_max;
new->k.p = new_max;
SET_BTREE_PTR_RANGE_UPDATED(&new->v, true);
ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i);
if (ret) {
kfree(new);
return ret;
}
bch2_btree_node_drop_keys_outside_node(b);
mutex_lock(&c->btree_cache.lock);
bch2_btree_node_hash_remove(&c->btree_cache, b);
bkey_copy(&b->key, &new->k_i);
ret = __bch2_btree_node_hash_insert(&c->btree_cache, b);
BUG_ON(ret);
mutex_unlock(&c->btree_cache.lock);
return 0;
}
static int btree_check_node_boundaries(struct bch_fs *c, struct btree *b,
struct btree *prev, struct btree *cur,
struct bpos *pulled_from_scan)
{
struct bpos expected_start = !prev
? b->data->min_key
: bpos_successor(prev->key.k.p);
struct printbuf buf = PRINTBUF;
int ret = 0;
BUG_ON(b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
!bpos_eq(bkey_i_to_btree_ptr_v2(&b->key)->v.min_key,
b->data->min_key));
if (bpos_eq(expected_start, cur->data->min_key))
return 0;
prt_printf(&buf, " at btree %s level %u:\n parent: ",
bch2_btree_id_str(b->c.btree_id), b->c.level);
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
if (prev) {
prt_printf(&buf, "\n prev: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&prev->key));
}
prt_str(&buf, "\n next: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&cur->key));
if (bpos_lt(expected_start, cur->data->min_key)) { /* gap */
if (b->c.level == 1 &&
bpos_lt(*pulled_from_scan, cur->data->min_key)) {
ret = bch2_get_scanned_nodes(c, b->c.btree_id, 0,
expected_start,
bpos_predecessor(cur->data->min_key));
if (ret)
goto err;
*pulled_from_scan = cur->data->min_key;
ret = DID_FILL_FROM_SCAN;
} else {
if (mustfix_fsck_err(c, btree_node_topology_bad_min_key,
"btree node with incorrect min_key%s", buf.buf))
ret = set_node_min(c, cur, expected_start);
}
} else { /* overlap */
if (prev && BTREE_NODE_SEQ(cur->data) > BTREE_NODE_SEQ(prev->data)) { /* cur overwrites prev */
if (bpos_ge(prev->data->min_key, cur->data->min_key)) { /* fully? */
if (mustfix_fsck_err(c, btree_node_topology_overwritten_by_next_node,
"btree node overwritten by next node%s", buf.buf))
ret = DROP_PREV_NODE;
} else {
if (mustfix_fsck_err(c, btree_node_topology_bad_max_key,
"btree node with incorrect max_key%s", buf.buf))
ret = set_node_max(c, prev,
bpos_predecessor(cur->data->min_key));
}
} else {
if (bpos_ge(expected_start, cur->data->max_key)) { /* fully? */
if (mustfix_fsck_err(c, btree_node_topology_overwritten_by_prev_node,
"btree node overwritten by prev node%s", buf.buf))
ret = DROP_THIS_NODE;
} else {
if (mustfix_fsck_err(c, btree_node_topology_bad_min_key,
"btree node with incorrect min_key%s", buf.buf))
ret = set_node_min(c, cur, expected_start);
}
}
}
err:
fsck_err:
printbuf_exit(&buf);
return ret;
}
static int btree_repair_node_end(struct bch_fs *c, struct btree *b,
struct btree *child, struct bpos *pulled_from_scan)
{
struct printbuf buf = PRINTBUF;
int ret = 0;
if (bpos_eq(child->key.k.p, b->key.k.p))
return 0;
prt_printf(&buf, "at btree %s level %u:\n parent: ",
bch2_btree_id_str(b->c.btree_id), b->c.level);
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
prt_str(&buf, "\n child: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&child->key));
if (mustfix_fsck_err(c, btree_node_topology_bad_max_key,
"btree node with incorrect max_key%s", buf.buf)) {
if (b->c.level == 1 &&
bpos_lt(*pulled_from_scan, b->key.k.p)) {
ret = bch2_get_scanned_nodes(c, b->c.btree_id, 0,
bpos_successor(child->key.k.p), b->key.k.p);
if (ret)
goto err;
*pulled_from_scan = b->key.k.p;
ret = DID_FILL_FROM_SCAN;
} else {
ret = set_node_max(c, child, b->key.k.p);
}
}
err:
fsck_err:
printbuf_exit(&buf);
return ret;
}
static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct btree *b,
struct bpos *pulled_from_scan)
{
struct bch_fs *c = trans->c;
struct btree_and_journal_iter iter;
struct bkey_s_c k;
struct bkey_buf prev_k, cur_k;
struct btree *prev = NULL, *cur = NULL;
bool have_child, new_pass = false;
struct printbuf buf = PRINTBUF;
int ret = 0;
if (!b->c.level)
return 0;
bch2_bkey_buf_init(&prev_k);
bch2_bkey_buf_init(&cur_k);
again:
cur = prev = NULL;
have_child = new_pass = false;
bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
iter.prefetch = true;
while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
BUG_ON(bpos_lt(k.k->p, b->data->min_key));
BUG_ON(bpos_gt(k.k->p, b->data->max_key));
bch2_btree_and_journal_iter_advance(&iter);
bch2_bkey_buf_reassemble(&cur_k, c, k);
cur = bch2_btree_node_get_noiter(trans, cur_k.k,
b->c.btree_id, b->c.level - 1,
false);
ret = PTR_ERR_OR_ZERO(cur);
printbuf_reset(&buf);
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(cur_k.k));
if (mustfix_fsck_err_on(bch2_err_matches(ret, EIO), c,
btree_node_unreadable,
"Topology repair: unreadable btree node at btree %s level %u:\n"
" %s",
bch2_btree_id_str(b->c.btree_id),
b->c.level - 1,
buf.buf)) {
bch2_btree_node_evict(trans, cur_k.k);
cur = NULL;
ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_scan_for_btree_nodes) ?:
bch2_journal_key_delete(c, b->c.btree_id,
b->c.level, cur_k.k->k.p);
if (ret)
break;
continue;
}
bch_err_msg(c, ret, "getting btree node");
if (ret)
break;
if (bch2_btree_node_is_stale(c, cur)) {
bch_info(c, "btree node %s older than nodes found by scanning", buf.buf);
six_unlock_read(&cur->c.lock);
bch2_btree_node_evict(trans, cur_k.k);
ret = bch2_journal_key_delete(c, b->c.btree_id,
b->c.level, cur_k.k->k.p);
cur = NULL;
if (ret)
break;
continue;
}
ret = btree_check_node_boundaries(c, b, prev, cur, pulled_from_scan);
if (ret == DID_FILL_FROM_SCAN) {
new_pass = true;
ret = 0;
}
if (ret == DROP_THIS_NODE) {
six_unlock_read(&cur->c.lock);
bch2_btree_node_evict(trans, cur_k.k);
ret = bch2_journal_key_delete(c, b->c.btree_id,
b->c.level, cur_k.k->k.p);
cur = NULL;
if (ret)
break;
continue;
}
if (prev)
six_unlock_read(&prev->c.lock);
prev = NULL;
if (ret == DROP_PREV_NODE) {
bch_info(c, "dropped prev node");
bch2_btree_node_evict(trans, prev_k.k);
ret = bch2_journal_key_delete(c, b->c.btree_id,
b->c.level, prev_k.k->k.p);
if (ret)
break;
bch2_btree_and_journal_iter_exit(&iter);
goto again;
} else if (ret)
break;
prev = cur;
cur = NULL;
bch2_bkey_buf_copy(&prev_k, c, cur_k.k);
}
if (!ret && !IS_ERR_OR_NULL(prev)) {
BUG_ON(cur);
ret = btree_repair_node_end(c, b, prev, pulled_from_scan);
if (ret == DID_FILL_FROM_SCAN) {
new_pass = true;
ret = 0;
}
}
if (!IS_ERR_OR_NULL(prev))
six_unlock_read(&prev->c.lock);
prev = NULL;
if (!IS_ERR_OR_NULL(cur))
six_unlock_read(&cur->c.lock);
cur = NULL;
if (ret)
goto err;
bch2_btree_and_journal_iter_exit(&iter);
if (new_pass)
goto again;
bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
iter.prefetch = true;
while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
bch2_bkey_buf_reassemble(&cur_k, c, k);
bch2_btree_and_journal_iter_advance(&iter);
cur = bch2_btree_node_get_noiter(trans, cur_k.k,
b->c.btree_id, b->c.level - 1,
false);
ret = PTR_ERR_OR_ZERO(cur);
bch_err_msg(c, ret, "getting btree node");
if (ret)
goto err;
ret = bch2_btree_repair_topology_recurse(trans, cur, pulled_from_scan);
six_unlock_read(&cur->c.lock);
cur = NULL;
if (ret == DROP_THIS_NODE) {
bch2_btree_node_evict(trans, cur_k.k);
ret = bch2_journal_key_delete(c, b->c.btree_id,
b->c.level, cur_k.k->k.p);
new_pass = true;
}
if (ret)
goto err;
have_child = true;
}
printbuf_reset(&buf);
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key));
if (mustfix_fsck_err_on(!have_child, c,
btree_node_topology_interior_node_empty,
"empty interior btree node at btree %s level %u\n"
" %s",
bch2_btree_id_str(b->c.btree_id),
b->c.level, buf.buf))
ret = DROP_THIS_NODE;
err:
fsck_err:
if (!IS_ERR_OR_NULL(prev))
six_unlock_read(&prev->c.lock);
if (!IS_ERR_OR_NULL(cur))
six_unlock_read(&cur->c.lock);
bch2_btree_and_journal_iter_exit(&iter);
if (!ret && new_pass)
goto again;
BUG_ON(!ret && bch2_btree_node_check_topology(trans, b));
bch2_bkey_buf_exit(&prev_k, c);
bch2_bkey_buf_exit(&cur_k, c);
printbuf_exit(&buf);
return ret;
}
int bch2_check_topology(struct bch_fs *c)
{
struct btree_trans *trans = bch2_trans_get(c);
struct bpos pulled_from_scan = POS_MIN;
int ret = 0;
for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) {
struct btree_root *r = bch2_btree_id_root(c, i);
bool reconstructed_root = false;
if (r->error) {
ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_scan_for_btree_nodes);
if (ret)
break;
reconstruct_root:
bch_info(c, "btree root %s unreadable, must recover from scan", bch2_btree_id_str(i));
r->alive = false;
r->error = 0;
if (!bch2_btree_has_scanned_nodes(c, i)) {
mustfix_fsck_err(c, btree_root_unreadable_and_scan_found_nothing,
"no nodes found for btree %s, continue?", bch2_btree_id_str(i));
bch2_btree_root_alloc_fake(c, i, 0);
} else {
bch2_btree_root_alloc_fake(c, i, 1);
ret = bch2_get_scanned_nodes(c, i, 0, POS_MIN, SPOS_MAX);
if (ret)
break;
}
bch2_shoot_down_journal_keys(c, i, 1, BTREE_MAX_DEPTH, POS_MIN, SPOS_MAX);
reconstructed_root = true;
}
struct btree *b = r->b;
btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read);
ret = bch2_btree_repair_topology_recurse(trans, b, &pulled_from_scan);
six_unlock_read(&b->c.lock);
if (ret == DROP_THIS_NODE) {
bch2_btree_node_hash_remove(&c->btree_cache, b);
mutex_lock(&c->btree_cache.lock);
list_move(&b->list, &c->btree_cache.freeable);
mutex_unlock(&c->btree_cache.lock);
r->b = NULL;
if (!reconstructed_root)
goto reconstruct_root;
bch_err(c, "empty btree root %s", bch2_btree_id_str(i));
bch2_btree_root_alloc_fake(c, i, 0);
r->alive = false;
ret = 0;
}
}
fsck_err:
bch2_trans_put(trans);
return ret;
}
static int bch2_check_fix_ptrs(struct btree_trans *trans, enum btree_id btree_id,
unsigned level, bool is_root,
struct bkey_s_c *k)
{
struct bch_fs *c = trans->c;
struct bkey_ptrs_c ptrs_c = bch2_bkey_ptrs_c(*k);
const union bch_extent_entry *entry_c;
struct extent_ptr_decoded p = { 0 };
bool do_update = false;
struct printbuf buf = PRINTBUF;
int ret = 0;
/*
* XXX
* use check_bucket_ref here
*/
bkey_for_each_ptr_decode(k->k, ptrs_c, p, entry_c) {
struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
struct bucket *g = PTR_GC_BUCKET(ca, &p.ptr);
enum bch_data_type data_type = bch2_bkey_ptr_data_type(*k, p, entry_c);
if (fsck_err_on(!g->gen_valid,
c, ptr_to_missing_alloc_key,
"bucket %u:%zu data type %s ptr gen %u missing in alloc btree\n"
"while marking %s",
p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
p.ptr.gen,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf))) {
if (!p.ptr.cached) {
g->gen_valid = true;
g->gen = p.ptr.gen;
} else {
do_update = true;
}
}
if (fsck_err_on(gen_cmp(p.ptr.gen, g->gen) > 0,
c, ptr_gen_newer_than_bucket_gen,
"bucket %u:%zu data type %s ptr gen in the future: %u > %u\n"
"while marking %s",
p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
p.ptr.gen, g->gen,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf))) {
if (!p.ptr.cached) {
g->gen_valid = true;
g->gen = p.ptr.gen;
g->data_type = 0;
g->dirty_sectors = 0;
g->cached_sectors = 0;
set_bit(BCH_FS_need_another_gc, &c->flags);
} else {
do_update = true;
}
}
if (fsck_err_on(gen_cmp(g->gen, p.ptr.gen) > BUCKET_GC_GEN_MAX,
c, ptr_gen_newer_than_bucket_gen,
"bucket %u:%zu gen %u data type %s: ptr gen %u too stale\n"
"while marking %s",
p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr), g->gen,
bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
p.ptr.gen,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
do_update = true;
if (fsck_err_on(!p.ptr.cached && gen_cmp(p.ptr.gen, g->gen) < 0,
c, stale_dirty_ptr,
"bucket %u:%zu data type %s stale dirty ptr: %u < %u\n"
"while marking %s",
p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
bch2_data_type_str(ptr_data_type(k->k, &p.ptr)),
p.ptr.gen, g->gen,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
do_update = true;
if (data_type != BCH_DATA_btree && p.ptr.gen != g->gen)
continue;
if (fsck_err_on(bucket_data_type(g->data_type) &&
bucket_data_type(g->data_type) !=
bucket_data_type(data_type), c,
ptr_bucket_data_type_mismatch,
"bucket %u:%zu different types of data in same bucket: %s, %s\n"
"while marking %s",
p.ptr.dev, PTR_BUCKET_NR(ca, &p.ptr),
bch2_data_type_str(g->data_type),
bch2_data_type_str(data_type),
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf))) {
if (data_type == BCH_DATA_btree) {
g->data_type = data_type;
set_bit(BCH_FS_need_another_gc, &c->flags);
} else {
do_update = true;
}
}
if (p.has_ec) {
struct gc_stripe *m = genradix_ptr(&c->gc_stripes, p.ec.idx);
if (fsck_err_on(!m || !m->alive, c,
ptr_to_missing_stripe,
"pointer to nonexistent stripe %llu\n"
"while marking %s",
(u64) p.ec.idx,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
do_update = true;
if (fsck_err_on(m && m->alive && !bch2_ptr_matches_stripe_m(m, p), c,
ptr_to_incorrect_stripe,
"pointer does not match stripe %llu\n"
"while marking %s",
(u64) p.ec.idx,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, *k), buf.buf)))
do_update = true;
}
}
if (do_update) {
if (is_root) {
bch_err(c, "cannot update btree roots yet");
ret = -EINVAL;
goto err;
}
struct bkey_i *new = kmalloc(bkey_bytes(k->k), GFP_KERNEL);
if (!new) {
ret = -BCH_ERR_ENOMEM_gc_repair_key;
bch_err_msg(c, ret, "allocating new key");
goto err;
}
bkey_reassemble(new, *k);
if (level) {
/*
* We don't want to drop btree node pointers - if the
* btree node isn't there anymore, the read path will
* sort it out:
*/
struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
bkey_for_each_ptr(ptrs, ptr) {
struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
struct bucket *g = PTR_GC_BUCKET(ca, ptr);
ptr->gen = g->gen;
}
} else {
struct bkey_ptrs ptrs;
union bch_extent_entry *entry;
restart_drop_ptrs:
ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
bkey_for_each_ptr_decode(bkey_i_to_s(new).k, ptrs, p, entry) {
struct bch_dev *ca = bch_dev_bkey_exists(c, p.ptr.dev);
struct bucket *g = PTR_GC_BUCKET(ca, &p.ptr);
enum bch_data_type data_type = bch2_bkey_ptr_data_type(bkey_i_to_s_c(new), p, entry);
if ((p.ptr.cached &&
(!g->gen_valid || gen_cmp(p.ptr.gen, g->gen) > 0)) ||
(!p.ptr.cached &&
gen_cmp(p.ptr.gen, g->gen) < 0) ||
gen_cmp(g->gen, p.ptr.gen) > BUCKET_GC_GEN_MAX ||
(g->data_type &&
g->data_type != data_type)) {
bch2_bkey_drop_ptr(bkey_i_to_s(new), &entry->ptr);
goto restart_drop_ptrs;
}
}
again:
ptrs = bch2_bkey_ptrs(bkey_i_to_s(new));
bkey_extent_entry_for_each(ptrs, entry) {
if (extent_entry_type(entry) == BCH_EXTENT_ENTRY_stripe_ptr) {
struct gc_stripe *m = genradix_ptr(&c->gc_stripes,
entry->stripe_ptr.idx);
union bch_extent_entry *next_ptr;
bkey_extent_entry_for_each_from(ptrs, next_ptr, entry)
if (extent_entry_type(next_ptr) == BCH_EXTENT_ENTRY_ptr)
goto found;
next_ptr = NULL;
found:
if (!next_ptr) {
bch_err(c, "aieee, found stripe ptr with no data ptr");
continue;
}
if (!m || !m->alive ||
!__bch2_ptr_matches_stripe(&m->ptrs[entry->stripe_ptr.block],
&next_ptr->ptr,
m->sectors)) {
bch2_bkey_extent_entry_drop(new, entry);
goto again;
}
}
}
}
if (level)
bch2_btree_node_update_key_early(trans, btree_id, level - 1, *k, new);
if (0) {
printbuf_reset(&buf);
bch2_bkey_val_to_text(&buf, c, *k);
bch_info(c, "updated %s", buf.buf);
printbuf_reset(&buf);
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(new));
bch_info(c, "new key %s", buf.buf);
}
ret = bch2_journal_key_insert_take(c, btree_id, level, new);
if (ret) {
kfree(new);
goto err;
}
*k = bkey_i_to_s_c(new);
}
err:
fsck_err:
printbuf_exit(&buf);
return ret;
}
/* marking of btree keys/nodes: */
static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
unsigned level, bool is_root,
struct bkey_s_c *k,
bool initial)
{
struct bch_fs *c = trans->c;
struct bkey deleted = KEY(0, 0, 0);
struct bkey_s_c old = (struct bkey_s_c) { &deleted, NULL };
int ret = 0;
deleted.p = k->k->p;
if (initial) {
BUG_ON(bch2_journal_seq_verify &&
k->k->version.lo > atomic64_read(&c->journal.seq));
if (fsck_err_on(k->k->version.lo > atomic64_read(&c->key_version), c,
bkey_version_in_future,
"key version number higher than recorded: %llu > %llu",
k->k->version.lo,
atomic64_read(&c->key_version)))
atomic64_set(&c->key_version, k->k->version.lo);
}
ret = bch2_check_fix_ptrs(trans, btree_id, level, is_root, k);
if (ret)
goto err;
ret = commit_do(trans, NULL, NULL, 0,
bch2_key_trigger(trans, btree_id, level, old,
unsafe_bkey_s_c_to_s(*k), BTREE_TRIGGER_GC));
fsck_err:
err:
bch_err_fn(c, ret);
return ret;
}
static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, bool initial)
{
struct btree_node_iter iter;
struct bkey unpacked;
struct bkey_s_c k;
int ret = 0;
ret = bch2_btree_node_check_topology(trans, b);
if (ret)
return ret;
if (!btree_node_type_needs_gc(btree_node_type(b)))
return 0;
bch2_btree_node_iter_init_from_start(&iter, b);
while ((k = bch2_btree_node_iter_peek_unpack(&iter, b, &unpacked)).k) {
ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, false,
&k, initial);
if (ret)
return ret;
bch2_btree_node_iter_advance(&iter, b);
}
return 0;
}
static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree_id,
bool initial, bool metadata_only)
{
struct bch_fs *c = trans->c;
struct btree_iter iter;
struct btree *b;
unsigned depth = metadata_only ? 1 : 0;
int ret = 0;
gc_pos_set(c, gc_pos_btree(btree_id, POS_MIN, 0));
__for_each_btree_node(trans, iter, btree_id, POS_MIN,
0, depth, BTREE_ITER_PREFETCH, b, ret) {
bch2_verify_btree_nr_keys(b);
gc_pos_set(c, gc_pos_btree_node(b));
ret = btree_gc_mark_node(trans, b, initial);
if (ret)
break;
}
bch2_trans_iter_exit(trans, &iter);
if (ret)
return ret;
mutex_lock(&c->btree_root_lock);
b = bch2_btree_id_root(c, btree_id)->b;
if (!btree_node_fake(b)) {
struct bkey_s_c k = bkey_i_to_s_c(&b->key);
ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level + 1,
true, &k, initial);
}
gc_pos_set(c, gc_pos_btree_root(b->c.btree_id));
mutex_unlock(&c->btree_root_lock);
return ret;
}
static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b,
unsigned target_depth)
{
struct bch_fs *c = trans->c;
struct btree_and_journal_iter iter;
struct bkey_s_c k;
struct bkey_buf cur;
struct printbuf buf = PRINTBUF;
int ret = 0;
ret = bch2_btree_node_check_topology(trans, b);
if (ret)
return ret;
bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
bch2_bkey_buf_init(&cur);
while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
BUG_ON(bpos_lt(k.k->p, b->data->min_key));
BUG_ON(bpos_gt(k.k->p, b->data->max_key));
ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level,
false, &k, true);
if (ret)
goto fsck_err;
bch2_btree_and_journal_iter_advance(&iter);
}
if (b->c.level > target_depth) {
bch2_btree_and_journal_iter_exit(&iter);
bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b);
iter.prefetch = true;
while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
struct btree *child;
bch2_bkey_buf_reassemble(&cur, c, k);
bch2_btree_and_journal_iter_advance(&iter);
child = bch2_btree_node_get_noiter(trans, cur.k,
b->c.btree_id, b->c.level - 1,
false);
ret = PTR_ERR_OR_ZERO(child);
if (bch2_err_matches(ret, EIO)) {
bch2_topology_error(c);
if (__fsck_err(c,
FSCK_CAN_FIX|
FSCK_CAN_IGNORE|
FSCK_NO_RATELIMIT,
btree_node_read_error,
"Unreadable btree node at btree %s level %u:\n"
" %s",
bch2_btree_id_str(b->c.btree_id),
b->c.level - 1,
(printbuf_reset(&buf),
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(cur.k)), buf.buf)) &&
should_restart_for_topology_repair(c)) {
bch_info(c, "Halting mark and sweep to start topology repair pass");
ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_check_topology);
goto fsck_err;
} else {
/* Continue marking when opted to not
* fix the error: */
ret = 0;
set_bit(BCH_FS_initial_gc_unfixed, &c->flags);
continue;
}
} else if (ret) {
bch_err_msg(c, ret, "getting btree node");
break;
}
ret = bch2_gc_btree_init_recurse(trans, child,
target_depth);
six_unlock_read(&child->c.lock);
if (ret)
break;
}
}
fsck_err:
bch2_bkey_buf_exit(&cur, c);
bch2_btree_and_journal_iter_exit(&iter);
printbuf_exit(&buf);
return ret;
}
static int bch2_gc_btree_init(struct btree_trans *trans,
enum btree_id btree_id,
bool metadata_only)
{
struct bch_fs *c = trans->c;
struct btree *b;
unsigned target_depth = metadata_only ? 1 : 0;
struct printbuf buf = PRINTBUF;
int ret = 0;
b = bch2_btree_id_root(c, btree_id)->b;
six_lock_read(&b->c.lock, NULL, NULL);
printbuf_reset(&buf);
bch2_bpos_to_text(&buf, b->data->min_key);
if (mustfix_fsck_err_on(!bpos_eq(b->data->min_key, POS_MIN), c,
btree_root_bad_min_key,
"btree root with incorrect min_key: %s", buf.buf)) {
bch_err(c, "repair unimplemented");
ret = -BCH_ERR_fsck_repair_unimplemented;
goto fsck_err;
}
printbuf_reset(&buf);
bch2_bpos_to_text(&buf, b->data->max_key);
if (mustfix_fsck_err_on(!bpos_eq(b->data->max_key, SPOS_MAX), c,
btree_root_bad_max_key,
"btree root with incorrect max_key: %s", buf.buf)) {
bch_err(c, "repair unimplemented");
ret = -BCH_ERR_fsck_repair_unimplemented;
goto fsck_err;
}
if (b->c.level >= target_depth)
ret = bch2_gc_btree_init_recurse(trans, b, target_depth);
if (!ret) {
struct bkey_s_c k = bkey_i_to_s_c(&b->key);
ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level + 1, true,
&k, true);
}
fsck_err:
six_unlock_read(&b->c.lock);
bch_err_fn(c, ret);
printbuf_exit(&buf);
return ret;
}
static inline int btree_id_gc_phase_cmp(enum btree_id l, enum btree_id r)
{
return (int) btree_id_to_gc_phase(l) -
(int) btree_id_to_gc_phase(r);
}
static int bch2_gc_btrees(struct bch_fs *c, bool initial, bool metadata_only)
{
struct btree_trans *trans = bch2_trans_get(c);
enum btree_id ids[BTREE_ID_NR];
unsigned i;
int ret = 0;
for (i = 0; i < BTREE_ID_NR; i++)
ids[i] = i;
bubble_sort(ids, BTREE_ID_NR, btree_id_gc_phase_cmp);
for (i = 0; i < BTREE_ID_NR && !ret; i++)
ret = initial
? bch2_gc_btree_init(trans, ids[i], metadata_only)
: bch2_gc_btree(trans, ids[i], initial, metadata_only);
for (i = BTREE_ID_NR; i < btree_id_nr_alive(c) && !ret; i++) {
if (!bch2_btree_id_root(c, i)->alive)
continue;
ret = initial
? bch2_gc_btree_init(trans, i, metadata_only)
: bch2_gc_btree(trans, i, initial, metadata_only);
}
bch2_trans_put(trans);
bch_err_fn(c, ret);
return ret;
}
static void mark_metadata_sectors(struct bch_fs *c, struct bch_dev *ca,
u64 start, u64 end,
enum bch_data_type type,
unsigned flags)
{
u64 b = sector_to_bucket(ca, start);
do {
unsigned sectors =
min_t(u64, bucket_to_sector(ca, b + 1), end) - start;
bch2_mark_metadata_bucket(c, ca, b, type, sectors,
gc_phase(GC_PHASE_SB), flags);
b++;
start += sectors;
} while (start < end);
}
static void bch2_mark_dev_superblock(struct bch_fs *c, struct bch_dev *ca,
unsigned flags)
{
struct bch_sb_layout *layout = &ca->disk_sb.sb->layout;
unsigned i;
u64 b;
for (i = 0; i < layout->nr_superblocks; i++) {
u64 offset = le64_to_cpu(layout->sb_offset[i]);
if (offset == BCH_SB_SECTOR)
mark_metadata_sectors(c, ca, 0, BCH_SB_SECTOR,
BCH_DATA_sb, flags);
mark_metadata_sectors(c, ca, offset,
offset + (1 << layout->sb_max_size_bits),
BCH_DATA_sb, flags);
}
for (i = 0; i < ca->journal.nr; i++) {
b = ca->journal.buckets[i];
bch2_mark_metadata_bucket(c, ca, b, BCH_DATA_journal,
ca->mi.bucket_size,
gc_phase(GC_PHASE_SB), flags);
}
}
static void bch2_mark_superblocks(struct bch_fs *c)
{
mutex_lock(&c->sb_lock);
gc_pos_set(c, gc_phase(GC_PHASE_SB));
for_each_online_member(c, ca)
bch2_mark_dev_superblock(c, ca, BTREE_TRIGGER_GC);
mutex_unlock(&c->sb_lock);
}
#if 0
/* Also see bch2_pending_btree_node_free_insert_done() */
static void bch2_mark_pending_btree_node_frees(struct bch_fs *c)
{
struct btree_update *as;
struct pending_btree_node_free *d;
mutex_lock(&c->btree_interior_update_lock);
gc_pos_set(c, gc_phase(GC_PHASE_PENDING_DELETE));
for_each_pending_btree_node_free(c, as, d)
if (d->index_update_done)
bch2_mark_key(c, bkey_i_to_s_c(&d->key), BTREE_TRIGGER_GC);
mutex_unlock(&c->btree_interior_update_lock);
}
#endif
static void bch2_gc_free(struct bch_fs *c)
{
genradix_free(&c->reflink_gc_table);
genradix_free(&c->gc_stripes);
for_each_member_device(c, ca) {
kvfree(rcu_dereference_protected(ca->buckets_gc, 1));
ca->buckets_gc = NULL;
free_percpu(ca->usage_gc);
ca->usage_gc = NULL;
}
free_percpu(c->usage_gc);
c->usage_gc = NULL;
}
static int bch2_gc_done(struct bch_fs *c,
bool initial, bool metadata_only)
{
struct bch_dev *ca = NULL;
struct printbuf buf = PRINTBUF;
bool verify = !metadata_only &&
!c->opts.reconstruct_alloc &&
(!initial || (c->sb.compat & (1ULL << BCH_COMPAT_alloc_info)));
unsigned i;
int ret = 0;
percpu_down_write(&c->mark_lock);
#define copy_field(_err, _f, _msg, ...) \
if (dst->_f != src->_f && \
(!verify || \
fsck_err(c, _err, _msg ": got %llu, should be %llu" \
, ##__VA_ARGS__, dst->_f, src->_f))) \
dst->_f = src->_f
#define copy_dev_field(_err, _f, _msg, ...) \
copy_field(_err, _f, "dev %u has wrong " _msg, ca->dev_idx, ##__VA_ARGS__)
#define copy_fs_field(_err, _f, _msg, ...) \
copy_field(_err, _f, "fs has wrong " _msg, ##__VA_ARGS__)
for (i = 0; i < ARRAY_SIZE(c->usage); i++)
bch2_fs_usage_acc_to_base(c, i);
__for_each_member_device(c, ca) {
struct bch_dev_usage *dst = ca->usage_base;
struct bch_dev_usage *src = (void *)
bch2_acc_percpu_u64s((u64 __percpu *) ca->usage_gc,
dev_usage_u64s());
for (i = 0; i < BCH_DATA_NR; i++) {
copy_dev_field(dev_usage_buckets_wrong,
d[i].buckets, "%s buckets", bch2_data_type_str(i));
copy_dev_field(dev_usage_sectors_wrong,
d[i].sectors, "%s sectors", bch2_data_type_str(i));
copy_dev_field(dev_usage_fragmented_wrong,
d[i].fragmented, "%s fragmented", bch2_data_type_str(i));
}
}
{
unsigned nr = fs_usage_u64s(c);
struct bch_fs_usage *dst = c->usage_base;
struct bch_fs_usage *src = (void *)
bch2_acc_percpu_u64s((u64 __percpu *) c->usage_gc, nr);
copy_fs_field(fs_usage_hidden_wrong,
b.hidden, "hidden");
copy_fs_field(fs_usage_btree_wrong,
b.btree, "btree");
if (!metadata_only) {
copy_fs_field(fs_usage_data_wrong,
b.data, "data");
copy_fs_field(fs_usage_cached_wrong,
b.cached, "cached");
copy_fs_field(fs_usage_reserved_wrong,
b.reserved, "reserved");
copy_fs_field(fs_usage_nr_inodes_wrong,
b.nr_inodes,"nr_inodes");
for (i = 0; i < BCH_REPLICAS_MAX; i++)
copy_fs_field(fs_usage_persistent_reserved_wrong,
persistent_reserved[i],
"persistent_reserved[%i]", i);
}
for (i = 0; i < c->replicas.nr; i++) {
struct bch_replicas_entry_v1 *e =
cpu_replicas_entry(&c->replicas, i);
if (metadata_only &&
(e->data_type == BCH_DATA_user ||
e->data_type == BCH_DATA_cached))
continue;
printbuf_reset(&buf);
bch2_replicas_entry_to_text(&buf, e);
copy_fs_field(fs_usage_replicas_wrong,
replicas[i], "%s", buf.buf);
}
}
#undef copy_fs_field
#undef copy_dev_field
#undef copy_stripe_field
#undef copy_field
fsck_err:
if (ca)
percpu_ref_put(&ca->ref);
bch_err_fn(c, ret);
percpu_up_write(&c->mark_lock);
printbuf_exit(&buf);
return ret;
}
static int bch2_gc_start(struct bch_fs *c)
{
BUG_ON(c->usage_gc);
c->usage_gc = __alloc_percpu_gfp(fs_usage_u64s(c) * sizeof(u64),
sizeof(u64), GFP_KERNEL);
if (!c->usage_gc) {
bch_err(c, "error allocating c->usage_gc");
return -BCH_ERR_ENOMEM_gc_start;
}
for_each_member_device(c, ca) {
BUG_ON(ca->usage_gc);
ca->usage_gc = alloc_percpu(struct bch_dev_usage);
if (!ca->usage_gc) {
bch_err(c, "error allocating ca->usage_gc");
percpu_ref_put(&ca->ref);
return -BCH_ERR_ENOMEM_gc_start;
}
this_cpu_write(ca->usage_gc->d[BCH_DATA_free].buckets,
ca->mi.nbuckets - ca->mi.first_bucket);
}
return 0;
}
static int bch2_gc_reset(struct bch_fs *c)
{
for_each_member_device(c, ca) {
free_percpu(ca->usage_gc);
ca->usage_gc = NULL;
}
free_percpu(c->usage_gc);
c->usage_gc = NULL;
return bch2_gc_start(c);
}
/* returns true if not equal */
static inline bool bch2_alloc_v4_cmp(struct bch_alloc_v4 l,
struct bch_alloc_v4 r)
{
return l.gen != r.gen ||
l.oldest_gen != r.oldest_gen ||
l.data_type != r.data_type ||
l.dirty_sectors != r.dirty_sectors ||
l.cached_sectors != r.cached_sectors ||
l.stripe_redundancy != r.stripe_redundancy ||
l.stripe != r.stripe;
}
static int bch2_alloc_write_key(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k,
bool metadata_only)
{
struct bch_fs *c = trans->c;
struct bch_dev *ca = bch_dev_bkey_exists(c, iter->pos.inode);
struct bucket old_gc, gc, *b;
struct bkey_i_alloc_v4 *a;
struct bch_alloc_v4 old_convert, new;
const struct bch_alloc_v4 *old;
int ret;
old = bch2_alloc_to_v4(k, &old_convert);
new = *old;
percpu_down_read(&c->mark_lock);
b = gc_bucket(ca, iter->pos.offset);
old_gc = *b;
if ((old->data_type == BCH_DATA_sb ||
old->data_type == BCH_DATA_journal) &&
!bch2_dev_is_online(ca)) {
b->data_type = old->data_type;
b->dirty_sectors = old->dirty_sectors;
}
/*
* b->data_type doesn't yet include need_discard & need_gc_gen states -
* fix that here:
*/
b->data_type = __alloc_data_type(b->dirty_sectors,
b->cached_sectors,
b->stripe,
*old,
b->data_type);
gc = *b;
if (gc.data_type != old_gc.data_type ||
gc.dirty_sectors != old_gc.dirty_sectors)
bch2_dev_usage_update_m(c, ca, &old_gc, &gc);
percpu_up_read(&c->mark_lock);
if (metadata_only &&
gc.data_type != BCH_DATA_sb &&
gc.data_type != BCH_DATA_journal &&
gc.data_type != BCH_DATA_btree)
return 0;
if (gen_after(old->gen, gc.gen))
return 0;
if (fsck_err_on(new.data_type != gc.data_type, c,
alloc_key_data_type_wrong,
"bucket %llu:%llu gen %u has wrong data_type"
": got %s, should be %s",
iter->pos.inode, iter->pos.offset,
gc.gen,
bch2_data_type_str(new.data_type),
bch2_data_type_str(gc.data_type)))
new.data_type = gc.data_type;
#define copy_bucket_field(_errtype, _f) \
if (fsck_err_on(new._f != gc._f, c, _errtype, \
"bucket %llu:%llu gen %u data type %s has wrong " #_f \
": got %u, should be %u", \
iter->pos.inode, iter->pos.offset, \
gc.gen, \
bch2_data_type_str(gc.data_type), \
new._f, gc._f)) \
new._f = gc._f; \
copy_bucket_field(alloc_key_gen_wrong,
gen);
copy_bucket_field(alloc_key_dirty_sectors_wrong,
dirty_sectors);
copy_bucket_field(alloc_key_cached_sectors_wrong,
cached_sectors);
copy_bucket_field(alloc_key_stripe_wrong,
stripe);
copy_bucket_field(alloc_key_stripe_redundancy_wrong,
stripe_redundancy);
#undef copy_bucket_field
if (!bch2_alloc_v4_cmp(*old, new))
return 0;
a = bch2_alloc_to_v4_mut(trans, k);
ret = PTR_ERR_OR_ZERO(a);
if (ret)
return ret;
a->v = new;
/*
* The trigger normally makes sure this is set, but we're not running
* triggers:
*/
if (a->v.data_type == BCH_DATA_cached && !a->v.io_time[READ])
a->v.io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
ret = bch2_trans_update(trans, iter, &a->k_i, BTREE_TRIGGER_NORUN);
fsck_err:
return ret;
}
static int bch2_gc_alloc_done(struct bch_fs *c, bool metadata_only)
{
int ret = 0;
for_each_member_device(c, ca) {
ret = bch2_trans_run(c,
for_each_btree_key_upto_commit(trans, iter, BTREE_ID_alloc,
POS(ca->dev_idx, ca->mi.first_bucket),
POS(ca->dev_idx, ca->mi.nbuckets - 1),
BTREE_ITER_SLOTS|BTREE_ITER_PREFETCH, k,
NULL, NULL, BCH_TRANS_COMMIT_lazy_rw,
bch2_alloc_write_key(trans, &iter, k, metadata_only)));
if (ret) {
percpu_ref_put(&ca->ref);
break;
}
}
bch_err_fn(c, ret);
return ret;
}
static int bch2_gc_alloc_start(struct bch_fs *c, bool metadata_only)
{
for_each_member_device(c, ca) {
struct bucket_array *buckets = kvmalloc(sizeof(struct bucket_array) +
ca->mi.nbuckets * sizeof(struct bucket),
GFP_KERNEL|__GFP_ZERO);
if (!buckets) {
percpu_ref_put(&ca->ref);
bch_err(c, "error allocating ca->buckets[gc]");
return -BCH_ERR_ENOMEM_gc_alloc_start;
}
buckets->first_bucket = ca->mi.first_bucket;
buckets->nbuckets = ca->mi.nbuckets;
rcu_assign_pointer(ca->buckets_gc, buckets);
}
int ret = bch2_trans_run(c,
for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
BTREE_ITER_PREFETCH, k, ({
struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
struct bucket *g = gc_bucket(ca, k.k->p.offset);
struct bch_alloc_v4 a_convert;
const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
g->gen_valid = 1;
g->gen = a->gen;
if (metadata_only &&
(a->data_type == BCH_DATA_user ||
a->data_type == BCH_DATA_cached ||
a->data_type == BCH_DATA_parity)) {
g->data_type = a->data_type;
g->dirty_sectors = a->dirty_sectors;
g->cached_sectors = a->cached_sectors;
g->stripe = a->stripe;
g->stripe_redundancy = a->stripe_redundancy;
}
0;
})));
bch_err_fn(c, ret);
return ret;
}
static void bch2_gc_alloc_reset(struct bch_fs *c, bool metadata_only)
{
for_each_member_device(c, ca) {
struct bucket_array *buckets = gc_bucket_array(ca);
struct bucket *g;
for_each_bucket(g, buckets) {
if (metadata_only &&
(g->data_type == BCH_DATA_user ||
g->data_type == BCH_DATA_cached ||
g->data_type == BCH_DATA_parity))
continue;
g->data_type = 0;
g->dirty_sectors = 0;
g->cached_sectors = 0;
}
}
}
static int bch2_gc_write_reflink_key(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k,
size_t *idx)
{
struct bch_fs *c = trans->c;
const __le64 *refcount = bkey_refcount_c(k);
struct printbuf buf = PRINTBUF;
struct reflink_gc *r;
int ret = 0;
if (!refcount)
return 0;
while ((r = genradix_ptr(&c->reflink_gc_table, *idx)) &&
r->offset < k.k->p.offset)
++*idx;
if (!r ||
r->offset != k.k->p.offset ||
r->size != k.k->size) {
bch_err(c, "unexpected inconsistency walking reflink table at gc finish");
return -EINVAL;
}
if (fsck_err_on(r->refcount != le64_to_cpu(*refcount), c,
reflink_v_refcount_wrong,
"reflink key has wrong refcount:\n"
" %s\n"
" should be %u",
(bch2_bkey_val_to_text(&buf, c, k), buf.buf),
r->refcount)) {
struct bkey_i *new = bch2_bkey_make_mut_noupdate(trans, k);
ret = PTR_ERR_OR_ZERO(new);
if (ret)
return ret;
if (!r->refcount)
new->k.type = KEY_TYPE_deleted;
else
*bkey_refcount(bkey_i_to_s(new)) = cpu_to_le64(r->refcount);
ret = bch2_trans_update(trans, iter, new, 0);
}
fsck_err:
printbuf_exit(&buf);
return ret;
}
static int bch2_gc_reflink_done(struct bch_fs *c, bool metadata_only)
{
size_t idx = 0;
if (metadata_only)
return 0;
int ret = bch2_trans_run(c,
for_each_btree_key_commit(trans, iter,
BTREE_ID_reflink, POS_MIN,
BTREE_ITER_PREFETCH, k,
NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
bch2_gc_write_reflink_key(trans, &iter, k, &idx)));
c->reflink_gc_nr = 0;
return ret;
}
static int bch2_gc_reflink_start(struct bch_fs *c,
bool metadata_only)
{
if (metadata_only)
return 0;
c->reflink_gc_nr = 0;
int ret = bch2_trans_run(c,
for_each_btree_key(trans, iter, BTREE_ID_reflink, POS_MIN,
BTREE_ITER_PREFETCH, k, ({
const __le64 *refcount = bkey_refcount_c(k);
if (!refcount)
continue;
struct reflink_gc *r = genradix_ptr_alloc(&c->reflink_gc_table,
c->reflink_gc_nr++, GFP_KERNEL);
if (!r) {
ret = -BCH_ERR_ENOMEM_gc_reflink_start;
break;
}
r->offset = k.k->p.offset;
r->size = k.k->size;
r->refcount = 0;
0;
})));
bch_err_fn(c, ret);
return ret;
}
static void bch2_gc_reflink_reset(struct bch_fs *c, bool metadata_only)
{
struct genradix_iter iter;
struct reflink_gc *r;
genradix_for_each(&c->reflink_gc_table, iter, r)
r->refcount = 0;
}
static int bch2_gc_write_stripes_key(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct printbuf buf = PRINTBUF;
const struct bch_stripe *s;
struct gc_stripe *m;
bool bad = false;
unsigned i;
int ret = 0;
if (k.k->type != KEY_TYPE_stripe)
return 0;
s = bkey_s_c_to_stripe(k).v;
m = genradix_ptr(&c->gc_stripes, k.k->p.offset);
for (i = 0; i < s->nr_blocks; i++) {
u32 old = stripe_blockcount_get(s, i);
u32 new = (m ? m->block_sectors[i] : 0);
if (old != new) {
prt_printf(&buf, "stripe block %u has wrong sector count: got %u, should be %u\n",
i, old, new);
bad = true;
}
}
if (bad)
bch2_bkey_val_to_text(&buf, c, k);
if (fsck_err_on(bad, c, stripe_sector_count_wrong,
"%s", buf.buf)) {
struct bkey_i_stripe *new;
new = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
ret = PTR_ERR_OR_ZERO(new);
if (ret)
return ret;
bkey_reassemble(&new->k_i, k);
for (i = 0; i < new->v.nr_blocks; i++)
stripe_blockcount_set(&new->v, i, m ? m->block_sectors[i] : 0);
ret = bch2_trans_update(trans, iter, &new->k_i, 0);
}
fsck_err:
printbuf_exit(&buf);
return ret;
}
static int bch2_gc_stripes_done(struct bch_fs *c, bool metadata_only)
{
if (metadata_only)
return 0;
return bch2_trans_run(c,
for_each_btree_key_commit(trans, iter,
BTREE_ID_stripes, POS_MIN,
BTREE_ITER_PREFETCH, k,
NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
bch2_gc_write_stripes_key(trans, &iter, k)));
}
static void bch2_gc_stripes_reset(struct bch_fs *c, bool metadata_only)
{
genradix_free(&c->gc_stripes);
}
/**
* bch2_gc - walk _all_ references to buckets, and recompute them:
*
* @c: filesystem object
* @initial: are we in recovery?
* @metadata_only: are we just checking metadata references, or everything?
*
* Returns: 0 on success, or standard errcode on failure
*
* Order matters here:
* - Concurrent GC relies on the fact that we have a total ordering for
* everything that GC walks - see gc_will_visit_node(),
* gc_will_visit_root()
*
* - also, references move around in the course of index updates and
* various other crap: everything needs to agree on the ordering
* references are allowed to move around in - e.g., we're allowed to
* start with a reference owned by an open_bucket (the allocator) and
* move it to the btree, but not the reverse.
*
* This is necessary to ensure that gc doesn't miss references that
* move around - if references move backwards in the ordering GC
* uses, GC could skip past them
*/
int bch2_gc(struct bch_fs *c, bool initial, bool metadata_only)
{
unsigned iter = 0;
int ret;
lockdep_assert_held(&c->state_lock);
down_write(&c->gc_lock);
bch2_btree_interior_updates_flush(c);
ret = bch2_gc_start(c) ?:
bch2_gc_alloc_start(c, metadata_only) ?:
bch2_gc_reflink_start(c, metadata_only);
if (ret)
goto out;
again:
gc_pos_set(c, gc_phase(GC_PHASE_START));
bch2_mark_superblocks(c);
ret = bch2_gc_btrees(c, initial, metadata_only);
if (ret)
goto out;
#if 0
bch2_mark_pending_btree_node_frees(c);
#endif
c->gc_count++;
if (test_bit(BCH_FS_need_another_gc, &c->flags) ||
(!iter && bch2_test_restart_gc)) {
if (iter++ > 2) {
bch_info(c, "Unable to fix bucket gens, looping");
ret = -EINVAL;
goto out;
}
/*
* XXX: make sure gens we fixed got saved
*/
bch_info(c, "Second GC pass needed, restarting:");
clear_bit(BCH_FS_need_another_gc, &c->flags);
__gc_pos_set(c, gc_phase(GC_PHASE_NOT_RUNNING));
bch2_gc_stripes_reset(c, metadata_only);
bch2_gc_alloc_reset(c, metadata_only);
bch2_gc_reflink_reset(c, metadata_only);
ret = bch2_gc_reset(c);
if (ret)
goto out;
/* flush fsck errors, reset counters */
bch2_flush_fsck_errs(c);
goto again;
}
out:
if (!ret) {
bch2_journal_block(&c->journal);
ret = bch2_gc_alloc_done(c, metadata_only) ?:
bch2_gc_done(c, initial, metadata_only) ?:
bch2_gc_stripes_done(c, metadata_only) ?:
bch2_gc_reflink_done(c, metadata_only);
bch2_journal_unblock(&c->journal);
}
percpu_down_write(&c->mark_lock);
/* Indicates that gc is no longer in progress: */
__gc_pos_set(c, gc_phase(GC_PHASE_NOT_RUNNING));
bch2_gc_free(c);
percpu_up_write(&c->mark_lock);
up_write(&c->gc_lock);
/*
* At startup, allocations can happen directly instead of via the
* allocator thread - issue wakeup in case they blocked on gc_lock:
*/
closure_wake_up(&c->freelist_wait);
bch_err_fn(c, ret);
return ret;
}
static int gc_btree_gens_key(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
struct bkey_i *u;
int ret;
percpu_down_read(&c->mark_lock);
bkey_for_each_ptr(ptrs, ptr) {
struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
if (ptr_stale(ca, ptr) > 16) {
percpu_up_read(&c->mark_lock);
goto update;
}
}
bkey_for_each_ptr(ptrs, ptr) {
struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
u8 *gen = &ca->oldest_gen[PTR_BUCKET_NR(ca, ptr)];
if (gen_after(*gen, ptr->gen))
*gen = ptr->gen;
}
percpu_up_read(&c->mark_lock);
return 0;
update:
u = bch2_bkey_make_mut(trans, iter, &k, 0);
ret = PTR_ERR_OR_ZERO(u);
if (ret)
return ret;
bch2_extent_normalize(c, bkey_i_to_s(u));
return 0;
}
static int bch2_alloc_write_oldest_gen(struct btree_trans *trans, struct btree_iter *iter,
struct bkey_s_c k)
{
struct bch_dev *ca = bch_dev_bkey_exists(trans->c, iter->pos.inode);
struct bch_alloc_v4 a_convert;
const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
struct bkey_i_alloc_v4 *a_mut;
int ret;
if (a->oldest_gen == ca->oldest_gen[iter->pos.offset])
return 0;
a_mut = bch2_alloc_to_v4_mut(trans, k);
ret = PTR_ERR_OR_ZERO(a_mut);
if (ret)
return ret;
a_mut->v.oldest_gen = ca->oldest_gen[iter->pos.offset];
a_mut->v.data_type = alloc_data_type(a_mut->v, a_mut->v.data_type);
return bch2_trans_update(trans, iter, &a_mut->k_i, 0);
}
int bch2_gc_gens(struct bch_fs *c)
{
u64 b, start_time = local_clock();
int ret;
/*
* Ideally we would be using state_lock and not gc_lock here, but that
* introduces a deadlock in the RO path - we currently take the state
* lock at the start of going RO, thus the gc thread may get stuck:
*/
if (!mutex_trylock(&c->gc_gens_lock))
return 0;
trace_and_count(c, gc_gens_start, c);
down_read(&c->gc_lock);
for_each_member_device(c, ca) {
struct bucket_gens *gens = bucket_gens(ca);
BUG_ON(ca->oldest_gen);
ca->oldest_gen = kvmalloc(gens->nbuckets, GFP_KERNEL);
if (!ca->oldest_gen) {
percpu_ref_put(&ca->ref);
ret = -BCH_ERR_ENOMEM_gc_gens;
goto err;
}
for (b = gens->first_bucket;
b < gens->nbuckets; b++)
ca->oldest_gen[b] = gens->b[b];
}
for (unsigned i = 0; i < BTREE_ID_NR; i++)
if (btree_type_has_ptrs(i)) {
c->gc_gens_btree = i;
c->gc_gens_pos = POS_MIN;
ret = bch2_trans_run(c,
for_each_btree_key_commit(trans, iter, i,
POS_MIN,
BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS,
k,
NULL, NULL,
BCH_TRANS_COMMIT_no_enospc,
gc_btree_gens_key(trans, &iter, k)));
if (ret)
goto err;
}
ret = bch2_trans_run(c,
for_each_btree_key_commit(trans, iter, BTREE_ID_alloc,
POS_MIN,
BTREE_ITER_PREFETCH,
k,
NULL, NULL,
BCH_TRANS_COMMIT_no_enospc,
bch2_alloc_write_oldest_gen(trans, &iter, k)));
if (ret)
goto err;
c->gc_gens_btree = 0;
c->gc_gens_pos = POS_MIN;
c->gc_count++;
bch2_time_stats_update(&c->times[BCH_TIME_btree_gc], start_time);
trace_and_count(c, gc_gens_end, c);
err:
for_each_member_device(c, ca) {
kvfree(ca->oldest_gen);
ca->oldest_gen = NULL;
}
up_read(&c->gc_lock);
mutex_unlock(&c->gc_gens_lock);
if (!bch2_err_matches(ret, EROFS))
bch_err_fn(c, ret);
return ret;
}
static int bch2_gc_thread(void *arg)
{
struct bch_fs *c = arg;
struct io_clock *clock = &c->io_clock[WRITE];
unsigned long last = atomic64_read(&clock->now);
unsigned last_kick = atomic_read(&c->kick_gc);
set_freezable();
while (1) {
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
if (kthread_should_stop()) {
__set_current_state(TASK_RUNNING);
return 0;
}
if (atomic_read(&c->kick_gc) != last_kick)
break;
if (c->btree_gc_periodic) {
unsigned long next = last + c->capacity / 16;
if (atomic64_read(&clock->now) >= next)
break;
bch2_io_clock_schedule_timeout(clock, next);
} else {
schedule();
}
try_to_freeze();
}
__set_current_state(TASK_RUNNING);
last = atomic64_read(&clock->now);
last_kick = atomic_read(&c->kick_gc);
/*
* Full gc is currently incompatible with btree key cache:
*/
#if 0
ret = bch2_gc(c, false, false);
#else
bch2_gc_gens(c);
#endif
debug_check_no_locks_held();
}
return 0;
}
void bch2_gc_thread_stop(struct bch_fs *c)
{
struct task_struct *p;
p = c->gc_thread;
c->gc_thread = NULL;
if (p) {
kthread_stop(p);
put_task_struct(p);
}
}
int bch2_gc_thread_start(struct bch_fs *c)
{
struct task_struct *p;
if (c->gc_thread)
return 0;
p = kthread_create(bch2_gc_thread, c, "bch-gc/%s", c->name);
if (IS_ERR(p)) {
bch_err_fn(c, PTR_ERR(p));
return PTR_ERR(p);
}
get_task_struct(p);
c->gc_thread = p;
wake_up_process(p);
return 0;
}