bcachefs: Erasure coding now uses backpointers

This is only a start to updating erasure coding for backpointers - it's
still not working yet. The subsequent patch will delete our old in
memory backpointers for copygc, and this fixes a spurious EPERM
bug/error message.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2022-10-09 00:29:51 -04:00
parent 8e3f913e2a
commit dea5647e16

View file

@ -4,10 +4,12 @@
#include "bcachefs.h"
#include "alloc_foreground.h"
#include "backpointers.h"
#include "bkey_buf.h"
#include "bset.h"
#include "btree_gc.h"
#include "btree_update.h"
#include "btree_write_buffer.h"
#include "buckets.h"
#include "disk_groups.h"
#include "ec.h"
@ -826,21 +828,42 @@ static void extent_stripe_ptr_add(struct bkey_s_extent e,
}
static int ec_stripe_update_extent(struct btree_trans *trans,
struct btree_iter *iter,
struct bkey_s_c k,
struct bpos bucket, u8 gen,
struct ec_stripe_buf *s,
struct bpos end)
u64 *bp_offset)
{
struct bch_fs *c = trans->c;
struct bch_backpointer bp;
struct btree_iter iter;
struct bkey_s_c k;
const struct bch_extent_ptr *ptr_c;
struct bch_extent_ptr *ptr, *ec_ptr = NULL;
struct bkey_i *n;
int ret, dev, block;
if (bkey_cmp(bkey_start_pos(k.k), end) >= 0)
return 1;
ret = bch2_get_next_backpointer(trans, bucket, gen, bp_offset, &bp);
if (ret)
return ret;
if (*bp_offset == U64_MAX)
return 0;
if (bch2_fs_inconsistent_on(bp.level, c, "found btree node in erasure coded bucket!?"))
return -EIO;
k = bch2_backpointer_get_key(trans, &iter, bucket, *bp_offset, bp);
ret = bkey_err(k);
if (ret)
return ret;
if (!k.k) {
/*
* extent no longer exists - we could flush the btree
* write buffer and retry to verify, but no need:
*/
return 0;
}
if (extent_has_stripe_ptr(k, s->key.k.p.offset))
return 0;
goto out;
ptr_c = bkey_matches_stripe(&s->key.v, k, &block);
/*
@ -848,14 +871,14 @@ static int ec_stripe_update_extent(struct btree_trans *trans,
* XXX: should we be incrementing a counter?
*/
if (!ptr_c || ptr_c->cached)
return 0;
goto out;
dev = s->key.v.ptrs[block].dev;
n = bch2_bkey_make_mut(trans, k);
ret = PTR_ERR_OR_ZERO(n);
if (ret)
return ret;
goto out;
bch2_bkey_drop_ptrs(bkey_i_to_s(n), ptr, ptr->dev != dev);
ec_ptr = (void *) bch2_bkey_has_device(bkey_i_to_s_c(n), dev);
@ -863,22 +886,59 @@ static int ec_stripe_update_extent(struct btree_trans *trans,
extent_stripe_ptr_add(bkey_i_to_s_extent(n), s, ec_ptr, block);
return bch2_trans_update(trans, iter, n, 0);
ret = bch2_trans_update(trans, &iter, n, 0);
out:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
static int ec_stripe_update_extents(struct bch_fs *c,
struct ec_stripe_buf *s,
struct bkey *pos)
static int ec_stripe_update_bucket(struct btree_trans *trans, struct ec_stripe_buf *s,
unsigned block)
{
struct btree_iter iter;
struct bkey_s_c k;
struct bch_fs *c = trans->c;
struct bch_extent_ptr bucket = s->key.v.ptrs[block];
struct bpos bucket_pos = PTR_BUCKET_POS(c, &bucket);
u64 bp_offset = 0;
int ret = 0;
return bch2_trans_run(c,
for_each_btree_key_commit(&trans, iter,
BTREE_ID_extents, bkey_start_pos(pos),
BTREE_ITER_NOT_EXTENTS|BTREE_ITER_INTENT, k,
NULL, NULL, BTREE_INSERT_NOFAIL,
ec_stripe_update_extent(&trans, &iter, k, s, pos->p)));
while (1) {
ret = commit_do(trans, NULL, NULL,
BTREE_INSERT_NOFAIL,
ec_stripe_update_extent(trans, bucket_pos, bucket.gen,
s, &bp_offset));
if (ret)
break;
if (bp_offset == U64_MAX)
break;
bp_offset++;
}
return ret;
}
static int ec_stripe_update_extents(struct bch_fs *c, struct ec_stripe_buf *s)
{
struct btree_trans trans;
struct bch_stripe *v = &s->key.v;
unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
int ret = 0;
bch2_trans_init(&trans, c, 0, 0);
ret = bch2_btree_write_buffer_flush(&trans);
if (ret)
goto err;
for (i = 0; i < nr_data; i++) {
ret = ec_stripe_update_bucket(&trans, s, i);
if (ret)
break;
}
err:
bch2_trans_exit(&trans);
return ret;
}
/*
@ -888,7 +948,6 @@ static void ec_stripe_create(struct ec_stripe_new *s)
{
struct bch_fs *c = s->c;
struct open_bucket *ob;
struct bkey_i *k;
struct stripe *m;
struct bch_stripe *v = &s->new_stripe.key.v;
unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
@ -948,14 +1007,10 @@ static void ec_stripe_create(struct ec_stripe_new *s)
goto err_put_writes;
}
for_each_keylist_key(&s->keys, k) {
ret = ec_stripe_update_extents(c, &s->new_stripe, &k->k);
if (ret) {
bch_err(c, "error creating stripe: error updating pointers: %s",
bch2_err_str(ret));
break;
}
}
ret = ec_stripe_update_extents(c, &s->new_stripe);
if (ret)
bch_err(c, "error creating stripe: error updating pointers: %s",
bch2_err_str(ret));
spin_lock(&c->ec_stripes_heap_lock);
m = genradix_ptr(&c->stripes, s->new_stripe.key.k.p.offset);
@ -1423,7 +1478,7 @@ static int __bch2_ec_stripe_head_reuse(struct bch_fs *c,
}
bkey_copy(&h->s->new_stripe.key.k_i,
&h->s->existing_stripe.key.k_i);
&h->s->existing_stripe.key.k_i);
return 0;
}