linux/fs/bcachefs/data_update.c
Kent Overstreet d8585a79be bcachefs: bch2_dev_have_ref()
bch2_dev_bkey_exists() is going away; bch2_dev_have_ref() documents that
we're looking up a device without checking if it's present because we
have a reference to it already.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-05-08 17:29:24 -04:00

697 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "alloc_foreground.h"
#include "bkey_buf.h"
#include "btree_update.h"
#include "buckets.h"
#include "data_update.h"
#include "ec.h"
#include "error.h"
#include "extents.h"
#include "io_write.h"
#include "keylist.h"
#include "move.h"
#include "nocow_locking.h"
#include "rebalance.h"
#include "snapshot.h"
#include "subvolume.h"
#include "trace.h"
static void trace_move_extent_finish2(struct bch_fs *c, struct bkey_s_c k)
{
if (trace_move_extent_finish_enabled()) {
struct printbuf buf = PRINTBUF;
bch2_bkey_val_to_text(&buf, c, k);
trace_move_extent_finish(c, buf.buf);
printbuf_exit(&buf);
}
}
static void trace_move_extent_fail2(struct data_update *m,
struct bkey_s_c new,
struct bkey_s_c wrote,
struct bkey_i *insert,
const char *msg)
{
struct bch_fs *c = m->op.c;
struct bkey_s_c old = bkey_i_to_s_c(m->k.k);
const union bch_extent_entry *entry;
struct bch_extent_ptr *ptr;
struct extent_ptr_decoded p;
struct printbuf buf = PRINTBUF;
unsigned i, rewrites_found = 0;
if (!trace_move_extent_fail_enabled())
return;
prt_str(&buf, msg);
if (insert) {
i = 0;
bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs_c(old), p, entry) {
if (((1U << i) & m->data_opts.rewrite_ptrs) &&
(ptr = bch2_extent_has_ptr(old, p, bkey_i_to_s(insert))) &&
!ptr->cached)
rewrites_found |= 1U << i;
i++;
}
}
prt_printf(&buf, "\nrewrite ptrs: %u%u%u%u",
(m->data_opts.rewrite_ptrs & (1 << 0)) != 0,
(m->data_opts.rewrite_ptrs & (1 << 1)) != 0,
(m->data_opts.rewrite_ptrs & (1 << 2)) != 0,
(m->data_opts.rewrite_ptrs & (1 << 3)) != 0);
prt_printf(&buf, "\nrewrites found: %u%u%u%u",
(rewrites_found & (1 << 0)) != 0,
(rewrites_found & (1 << 1)) != 0,
(rewrites_found & (1 << 2)) != 0,
(rewrites_found & (1 << 3)) != 0);
prt_str(&buf, "\nold: ");
bch2_bkey_val_to_text(&buf, c, old);
prt_str(&buf, "\nnew: ");
bch2_bkey_val_to_text(&buf, c, new);
prt_str(&buf, "\nwrote: ");
bch2_bkey_val_to_text(&buf, c, wrote);
if (insert) {
prt_str(&buf, "\ninsert: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));
}
trace_move_extent_fail(c, buf.buf);
printbuf_exit(&buf);
}
static int __bch2_data_update_index_update(struct btree_trans *trans,
struct bch_write_op *op)
{
struct bch_fs *c = op->c;
struct btree_iter iter;
struct data_update *m =
container_of(op, struct data_update, op);
struct keylist *keys = &op->insert_keys;
struct bkey_buf _new, _insert;
int ret = 0;
bch2_bkey_buf_init(&_new);
bch2_bkey_buf_init(&_insert);
bch2_bkey_buf_realloc(&_insert, c, U8_MAX);
bch2_trans_iter_init(trans, &iter, m->btree_id,
bkey_start_pos(&bch2_keylist_front(keys)->k),
BTREE_ITER_slots|BTREE_ITER_intent);
while (1) {
struct bkey_s_c k;
struct bkey_s_c old = bkey_i_to_s_c(m->k.k);
struct bkey_i *insert = NULL;
struct bkey_i_extent *new;
const union bch_extent_entry *entry_c;
union bch_extent_entry *entry;
struct extent_ptr_decoded p;
struct bch_extent_ptr *ptr;
const struct bch_extent_ptr *ptr_c;
struct bpos next_pos;
bool should_check_enospc;
s64 i_sectors_delta = 0, disk_sectors_delta = 0;
unsigned rewrites_found = 0, durability, i;
bch2_trans_begin(trans);
k = bch2_btree_iter_peek_slot(&iter);
ret = bkey_err(k);
if (ret)
goto err;
new = bkey_i_to_extent(bch2_keylist_front(keys));
if (!bch2_extents_match(k, old)) {
trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i),
NULL, "no match:");
goto nowork;
}
bkey_reassemble(_insert.k, k);
insert = _insert.k;
bch2_bkey_buf_copy(&_new, c, bch2_keylist_front(keys));
new = bkey_i_to_extent(_new.k);
bch2_cut_front(iter.pos, &new->k_i);
bch2_cut_front(iter.pos, insert);
bch2_cut_back(new->k.p, insert);
bch2_cut_back(insert->k.p, &new->k_i);
/*
* @old: extent that we read from
* @insert: key that we're going to update, initialized from
* extent currently in btree - same as @old unless we raced with
* other updates
* @new: extent with new pointers that we'll be adding to @insert
*
* Fist, drop rewrite_ptrs from @new:
*/
i = 0;
bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs_c(old), p, entry_c) {
if (((1U << i) & m->data_opts.rewrite_ptrs) &&
(ptr = bch2_extent_has_ptr(old, p, bkey_i_to_s(insert))) &&
!ptr->cached) {
bch2_extent_ptr_set_cached(bkey_i_to_s(insert), ptr);
rewrites_found |= 1U << i;
}
i++;
}
if (m->data_opts.rewrite_ptrs &&
!rewrites_found &&
bch2_bkey_durability(c, k) >= m->op.opts.data_replicas) {
trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "no rewrites found:");
goto nowork;
}
/*
* A replica that we just wrote might conflict with a replica
* that we want to keep, due to racing with another move:
*/
restart_drop_conflicting_replicas:
extent_for_each_ptr(extent_i_to_s(new), ptr)
if ((ptr_c = bch2_bkey_has_device_c(bkey_i_to_s_c(insert), ptr->dev)) &&
!ptr_c->cached) {
bch2_bkey_drop_ptr_noerror(bkey_i_to_s(&new->k_i), ptr);
goto restart_drop_conflicting_replicas;
}
if (!bkey_val_u64s(&new->k)) {
trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "new replicas conflicted:");
goto nowork;
}
/* Now, drop pointers that conflict with what we just wrote: */
extent_for_each_ptr_decode(extent_i_to_s(new), p, entry)
if ((ptr = bch2_bkey_has_device(bkey_i_to_s(insert), p.ptr.dev)))
bch2_bkey_drop_ptr_noerror(bkey_i_to_s(insert), ptr);
durability = bch2_bkey_durability(c, bkey_i_to_s_c(insert)) +
bch2_bkey_durability(c, bkey_i_to_s_c(&new->k_i));
/* Now, drop excess replicas: */
restart_drop_extra_replicas:
rcu_read_lock();
bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs(bkey_i_to_s(insert)), p, entry) {
unsigned ptr_durability = bch2_extent_ptr_durability(c, &p);
if (!p.ptr.cached &&
durability - ptr_durability >= m->op.opts.data_replicas) {
durability -= ptr_durability;
bch2_extent_ptr_set_cached(bkey_i_to_s(insert), &entry->ptr);
goto restart_drop_extra_replicas;
}
}
rcu_read_unlock();
/* Finally, add the pointers we just wrote: */
extent_for_each_ptr_decode(extent_i_to_s(new), p, entry)
bch2_extent_ptr_decoded_append(insert, &p);
bch2_bkey_narrow_crcs(insert, (struct bch_extent_crc_unpacked) { 0 });
bch2_extent_normalize(c, bkey_i_to_s(insert));
ret = bch2_sum_sector_overwrites(trans, &iter, insert,
&should_check_enospc,
&i_sectors_delta,
&disk_sectors_delta);
if (ret)
goto err;
if (disk_sectors_delta > (s64) op->res.sectors) {
ret = bch2_disk_reservation_add(c, &op->res,
disk_sectors_delta - op->res.sectors,
!should_check_enospc
? BCH_DISK_RESERVATION_NOFAIL : 0);
if (ret)
goto out;
}
next_pos = insert->k.p;
/*
* Check for nonce offset inconsistency:
* This is debug code - we've been seeing this bug rarely, and
* it's been hard to reproduce, so this should give us some more
* information when it does occur:
*/
struct printbuf err = PRINTBUF;
int invalid = bch2_bkey_invalid(c, bkey_i_to_s_c(insert), __btree_node_type(0, m->btree_id), 0, &err);
printbuf_exit(&err);
if (invalid) {
struct printbuf buf = PRINTBUF;
prt_str(&buf, "about to insert invalid key in data update path");
prt_str(&buf, "\nold: ");
bch2_bkey_val_to_text(&buf, c, old);
prt_str(&buf, "\nk: ");
bch2_bkey_val_to_text(&buf, c, k);
prt_str(&buf, "\nnew: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));
bch2_print_string_as_lines(KERN_ERR, buf.buf);
printbuf_exit(&buf);
bch2_fatal_error(c);
goto out;
}
if (trace_data_update_enabled()) {
struct printbuf buf = PRINTBUF;
prt_str(&buf, "\nold: ");
bch2_bkey_val_to_text(&buf, c, old);
prt_str(&buf, "\nk: ");
bch2_bkey_val_to_text(&buf, c, k);
prt_str(&buf, "\nnew: ");
bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));
trace_data_update(c, buf.buf);
printbuf_exit(&buf);
}
ret = bch2_insert_snapshot_whiteouts(trans, m->btree_id,
k.k->p, bkey_start_pos(&insert->k)) ?:
bch2_insert_snapshot_whiteouts(trans, m->btree_id,
k.k->p, insert->k.p) ?:
bch2_bkey_set_needs_rebalance(c, insert, &op->opts) ?:
bch2_trans_update(trans, &iter, insert,
BTREE_UPDATE_internal_snapshot_node) ?:
bch2_trans_commit(trans, &op->res,
NULL,
BCH_TRANS_COMMIT_no_check_rw|
BCH_TRANS_COMMIT_no_enospc|
m->data_opts.btree_insert_flags);
if (!ret) {
bch2_btree_iter_set_pos(&iter, next_pos);
this_cpu_add(c->counters[BCH_COUNTER_move_extent_finish], new->k.size);
trace_move_extent_finish2(c, bkey_i_to_s_c(&new->k_i));
}
err:
if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
ret = 0;
if (ret)
break;
next:
while (bkey_ge(iter.pos, bch2_keylist_front(keys)->k.p)) {
bch2_keylist_pop_front(keys);
if (bch2_keylist_empty(keys))
goto out;
}
continue;
nowork:
if (m->stats) {
BUG_ON(k.k->p.offset <= iter.pos.offset);
atomic64_inc(&m->stats->keys_raced);
atomic64_add(k.k->p.offset - iter.pos.offset,
&m->stats->sectors_raced);
}
count_event(c, move_extent_fail);
bch2_btree_iter_advance(&iter);
goto next;
}
out:
bch2_trans_iter_exit(trans, &iter);
bch2_bkey_buf_exit(&_insert, c);
bch2_bkey_buf_exit(&_new, c);
BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart));
return ret;
}
int bch2_data_update_index_update(struct bch_write_op *op)
{
return bch2_trans_run(op->c, __bch2_data_update_index_update(trans, op));
}
void bch2_data_update_read_done(struct data_update *m,
struct bch_extent_crc_unpacked crc)
{
/* write bio must own pages: */
BUG_ON(!m->op.wbio.bio.bi_vcnt);
m->op.crc = crc;
m->op.wbio.bio.bi_iter.bi_size = crc.compressed_size << 9;
closure_call(&m->op.cl, bch2_write, NULL, NULL);
}
void bch2_data_update_exit(struct data_update *update)
{
struct bch_fs *c = update->op.c;
struct bkey_ptrs_c ptrs =
bch2_bkey_ptrs_c(bkey_i_to_s_c(update->k.k));
bkey_for_each_ptr(ptrs, ptr) {
struct bch_dev *ca = bch2_dev_have_ref(c, ptr->dev);
if (c->opts.nocow_enabled)
bch2_bucket_nocow_unlock(&c->nocow_locks,
PTR_BUCKET_POS(ca, ptr), 0);
bch2_dev_put(ca);
}
bch2_bkey_buf_exit(&update->k, c);
bch2_disk_reservation_put(c, &update->op.res);
bch2_bio_free_pages_pool(c, &update->op.wbio.bio);
}
static void bch2_update_unwritten_extent(struct btree_trans *trans,
struct data_update *update)
{
struct bch_fs *c = update->op.c;
struct bio *bio = &update->op.wbio.bio;
struct bkey_i_extent *e;
struct write_point *wp;
struct closure cl;
struct btree_iter iter;
struct bkey_s_c k;
int ret;
closure_init_stack(&cl);
bch2_keylist_init(&update->op.insert_keys, update->op.inline_keys);
while (bio_sectors(bio)) {
unsigned sectors = bio_sectors(bio);
bch2_trans_begin(trans);
bch2_trans_iter_init(trans, &iter, update->btree_id, update->op.pos,
BTREE_ITER_slots);
ret = lockrestart_do(trans, ({
k = bch2_btree_iter_peek_slot(&iter);
bkey_err(k);
}));
bch2_trans_iter_exit(trans, &iter);
if (ret || !bch2_extents_match(k, bkey_i_to_s_c(update->k.k)))
break;
e = bkey_extent_init(update->op.insert_keys.top);
e->k.p = update->op.pos;
ret = bch2_alloc_sectors_start_trans(trans,
update->op.target,
false,
update->op.write_point,
&update->op.devs_have,
update->op.nr_replicas,
update->op.nr_replicas,
update->op.watermark,
0, &cl, &wp);
if (bch2_err_matches(ret, BCH_ERR_operation_blocked)) {
bch2_trans_unlock(trans);
closure_sync(&cl);
continue;
}
bch_err_fn_ratelimited(c, ret);
if (ret)
return;
sectors = min(sectors, wp->sectors_free);
bch2_key_resize(&e->k, sectors);
bch2_open_bucket_get(c, wp, &update->op.open_buckets);
bch2_alloc_sectors_append_ptrs(c, wp, &e->k_i, sectors, false);
bch2_alloc_sectors_done(c, wp);
bio_advance(bio, sectors << 9);
update->op.pos.offset += sectors;
extent_for_each_ptr(extent_i_to_s(e), ptr)
ptr->unwritten = true;
bch2_keylist_push(&update->op.insert_keys);
ret = __bch2_data_update_index_update(trans, &update->op);
bch2_open_buckets_put(c, &update->op.open_buckets);
if (ret)
break;
}
if (closure_nr_remaining(&cl) != 1) {
bch2_trans_unlock(trans);
closure_sync(&cl);
}
}
int bch2_extent_drop_ptrs(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k,
struct data_update_opts data_opts)
{
struct bch_fs *c = trans->c;
struct bkey_i *n;
int ret;
n = bch2_bkey_make_mut_noupdate(trans, k);
ret = PTR_ERR_OR_ZERO(n);
if (ret)
return ret;
while (data_opts.kill_ptrs) {
unsigned i = 0, drop = __fls(data_opts.kill_ptrs);
bch2_bkey_drop_ptrs(bkey_i_to_s(n), ptr, i++ == drop);
data_opts.kill_ptrs ^= 1U << drop;
}
/*
* If the new extent no longer has any pointers, bch2_extent_normalize()
* will do the appropriate thing with it (turning it into a
* KEY_TYPE_error key, or just a discard if it was a cached extent)
*/
bch2_extent_normalize(c, bkey_i_to_s(n));
/*
* Since we're not inserting through an extent iterator
* (BTREE_ITER_all_snapshots iterators aren't extent iterators),
* we aren't using the extent overwrite path to delete, we're
* just using the normal key deletion path:
*/
if (bkey_deleted(&n->k) && !(iter->flags & BTREE_ITER_is_extents))
n->k.size = 0;
return bch2_trans_relock(trans) ?:
bch2_trans_update(trans, iter, n, BTREE_UPDATE_internal_snapshot_node) ?:
bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
}
int bch2_data_update_init(struct btree_trans *trans,
struct btree_iter *iter,
struct moving_context *ctxt,
struct data_update *m,
struct write_point_specifier wp,
struct bch_io_opts io_opts,
struct data_update_opts data_opts,
enum btree_id btree_id,
struct bkey_s_c k)
{
struct bch_fs *c = trans->c;
struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
const union bch_extent_entry *entry;
struct extent_ptr_decoded p;
unsigned i, reserve_sectors = k.k->size * data_opts.extra_replicas;
unsigned ptrs_locked = 0;
int ret = 0;
/*
* fs is corrupt we have a key for a snapshot node that doesn't exist,
* and we have to check for this because we go rw before repairing the
* snapshots table - just skip it, we can move it later.
*/
if (unlikely(k.k->p.snapshot && !bch2_snapshot_equiv(c, k.k->p.snapshot)))
return -BCH_ERR_data_update_done;
bch2_bkey_buf_init(&m->k);
bch2_bkey_buf_reassemble(&m->k, c, k);
m->btree_id = btree_id;
m->data_opts = data_opts;
m->ctxt = ctxt;
m->stats = ctxt ? ctxt->stats : NULL;
bch2_write_op_init(&m->op, c, io_opts);
m->op.pos = bkey_start_pos(k.k);
m->op.version = k.k->version;
m->op.target = data_opts.target;
m->op.write_point = wp;
m->op.nr_replicas = 0;
m->op.flags |= BCH_WRITE_PAGES_STABLE|
BCH_WRITE_PAGES_OWNED|
BCH_WRITE_DATA_ENCODED|
BCH_WRITE_MOVE|
m->data_opts.write_flags;
m->op.compression_opt = background_compression(io_opts);
m->op.watermark = m->data_opts.btree_insert_flags & BCH_WATERMARK_MASK;
bkey_for_each_ptr(ptrs, ptr) {
if (!bch2_dev_tryget(c, ptr->dev)) {
bkey_for_each_ptr(ptrs, ptr2) {
if (ptr2 == ptr)
break;
bch2_dev_put(bch2_dev_have_ref(c, ptr2->dev));
}
return -BCH_ERR_data_update_done;
}
}
unsigned durability_have = 0, durability_removing = 0;
i = 0;
bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
struct bch_dev *ca = bch2_dev_have_ref(c, p.ptr.dev);
struct bpos bucket = PTR_BUCKET_POS(ca, &p.ptr);
bool locked;
rcu_read_lock();
if (((1U << i) & m->data_opts.rewrite_ptrs)) {
BUG_ON(p.ptr.cached);
if (crc_is_compressed(p.crc))
reserve_sectors += k.k->size;
m->op.nr_replicas += bch2_extent_ptr_desired_durability(c, &p);
durability_removing += bch2_extent_ptr_desired_durability(c, &p);
} else if (!p.ptr.cached &&
!((1U << i) & m->data_opts.kill_ptrs)) {
bch2_dev_list_add_dev(&m->op.devs_have, p.ptr.dev);
durability_have += bch2_extent_ptr_durability(c, &p);
}
rcu_read_unlock();
/*
* op->csum_type is normally initialized from the fs/file's
* current options - but if an extent is encrypted, we require
* that it stays encrypted:
*/
if (bch2_csum_type_is_encryption(p.crc.csum_type)) {
m->op.nonce = p.crc.nonce + p.crc.offset;
m->op.csum_type = p.crc.csum_type;
}
if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
m->op.incompressible = true;
if (c->opts.nocow_enabled) {
if (ctxt) {
move_ctxt_wait_event(ctxt,
(locked = bch2_bucket_nocow_trylock(&c->nocow_locks,
bucket, 0)) ||
list_empty(&ctxt->ios));
if (!locked)
bch2_bucket_nocow_lock(&c->nocow_locks, bucket, 0);
} else {
if (!bch2_bucket_nocow_trylock(&c->nocow_locks, bucket, 0)) {
ret = -BCH_ERR_nocow_lock_blocked;
goto err;
}
}
ptrs_locked |= (1U << i);
}
i++;
}
unsigned durability_required = max(0, (int) (io_opts.data_replicas - durability_have));
/*
* If current extent durability is less than io_opts.data_replicas,
* we're not trying to rereplicate the extent up to data_replicas here -
* unless extra_replicas was specified
*
* Increasing replication is an explicit operation triggered by
* rereplicate, currently, so that users don't get an unexpected -ENOSPC
*/
if (!(m->data_opts.write_flags & BCH_WRITE_CACHED) &&
!durability_required) {
m->data_opts.kill_ptrs |= m->data_opts.rewrite_ptrs;
m->data_opts.rewrite_ptrs = 0;
/* if iter == NULL, it's just a promote */
if (iter)
ret = bch2_extent_drop_ptrs(trans, iter, k, m->data_opts);
goto done;
}
m->op.nr_replicas = min(durability_removing, durability_required) +
m->data_opts.extra_replicas;
/*
* If device(s) were set to durability=0 after data was written to them
* we can end up with a duribilty=0 extent, and the normal algorithm
* that tries not to increase durability doesn't work:
*/
if (!(durability_have + durability_removing))
m->op.nr_replicas = max((unsigned) m->op.nr_replicas, 1);
m->op.nr_replicas_required = m->op.nr_replicas;
if (reserve_sectors) {
ret = bch2_disk_reservation_add(c, &m->op.res, reserve_sectors,
m->data_opts.extra_replicas
? 0
: BCH_DISK_RESERVATION_NOFAIL);
if (ret)
goto err;
}
if (bkey_extent_is_unwritten(k)) {
bch2_update_unwritten_extent(trans, m);
goto done;
}
return 0;
err:
i = 0;
bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
struct bch_dev *ca = bch2_dev_have_ref(c, p.ptr.dev);
struct bpos bucket = PTR_BUCKET_POS(ca, &p.ptr);
if ((1U << i) & ptrs_locked)
bch2_bucket_nocow_unlock(&c->nocow_locks, bucket, 0);
bch2_dev_put(ca);
i++;
}
bch2_bkey_buf_exit(&m->k, c);
bch2_bio_free_pages_pool(c, &m->op.wbio.bio);
return ret;
done:
bch2_data_update_exit(m);
return ret ?: -BCH_ERR_data_update_done;
}
void bch2_data_update_opts_normalize(struct bkey_s_c k, struct data_update_opts *opts)
{
struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
unsigned i = 0;
bkey_for_each_ptr(ptrs, ptr) {
if ((opts->rewrite_ptrs & (1U << i)) && ptr->cached) {
opts->kill_ptrs |= 1U << i;
opts->rewrite_ptrs ^= 1U << i;
}
i++;
}
}