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bcachefs: bch_stripe.disk_label

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When reshaping existing stripes, we should keep them on the same target
that they were allocated on; to do this, we need to add a field to the
btree stripe type.

This is a tad awkward, because we only have 8 bits left, and targets are
16 bits - but we only need to store a label, not a full target.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2024-09-01 14:54:42 -04:00
parent 1b11c4d365
commit fa85c47397
4 changed files with 43 additions and 16 deletions
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47
fs/bcachefs/ec.c
View File

@ -147,12 +147,18 @@ void bch2_stripe_to_text(struct printbuf *out, struct bch_fs *c,
bch2_prt_csum_type(out, s.csum_type);
prt_printf(out, " gran %u", 1U << s.csum_granularity_bits);
if (s.disk_label) {
prt_str(out, " label");
bch2_disk_path_to_text(out, c, s.disk_label - 1);
}
for (unsigned i = 0; i < s.nr_blocks; i++) {
const struct bch_extent_ptr *ptr = sp->ptrs + i;
if ((void *) ptr >= bkey_val_end(k))
break;
prt_char(out, ' ');
bch2_extent_ptr_to_text(out, c, ptr);
if (s.csum_type < BCH_CSUM_NR &&
@ -358,6 +364,7 @@ static inline void stripe_to_mem(struct stripe *m, const struct bch_stripe *s)
m->algorithm = s->algorithm;
m->nr_blocks = s->nr_blocks;
m->nr_redundant = s->nr_redundant;
m->disk_label = s->disk_label;
m->blocks_nonempty = 0;
for (unsigned i = 0; i < s->nr_blocks; i++)
@ -1647,7 +1654,8 @@ static void ec_stripe_key_init(struct bch_fs *c,
struct bkey_i *k,
unsigned nr_data,
unsigned nr_parity,
unsigned stripe_size)
unsigned stripe_size,
unsigned disk_label)
{
struct bkey_i_stripe *s = bkey_stripe_init(k);
unsigned u64s;
@ -1658,7 +1666,7 @@ static void ec_stripe_key_init(struct bch_fs *c,
s->v.nr_redundant = nr_parity;
s->v.csum_granularity_bits = ilog2(c->opts.encoded_extent_max >> 9);
s->v.csum_type = BCH_CSUM_crc32c;
s->v.pad = 0;
s->v.disk_label = disk_label;
while ((u64s = stripe_val_u64s(&s->v)) > BKEY_VAL_U64s_MAX) {
BUG_ON(1 << s->v.csum_granularity_bits >=
@ -1691,14 +1699,15 @@ static int ec_new_stripe_alloc(struct bch_fs *c, struct ec_stripe_head *h)
s->nr_parity = h->redundancy;
ec_stripe_key_init(c, &s->new_stripe.key,
s->nr_data, s->nr_parity, h->blocksize);
s->nr_data, s->nr_parity,
h->blocksize, h->disk_label);
h->s = s;
return 0;
}
static struct ec_stripe_head *
ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
ec_new_stripe_head_alloc(struct bch_fs *c, unsigned disk_label,
unsigned algo, unsigned redundancy,
enum bch_watermark watermark)
{
@ -1711,13 +1720,13 @@ ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
mutex_init(&h->lock);
BUG_ON(!mutex_trylock(&h->lock));
h->target = target;
h->disk_label = disk_label;
h->algo = algo;
h->redundancy = redundancy;
h->watermark = watermark;
rcu_read_lock();
h->devs = target_rw_devs(c, BCH_DATA_user, target);
h->devs = target_rw_devs(c, BCH_DATA_user, disk_label ? group_to_target(disk_label - 1) : 0);
for_each_member_device_rcu(c, ca, &h->devs)
if (!ca->mi.durability)
@ -1756,7 +1765,7 @@ void bch2_ec_stripe_head_put(struct bch_fs *c, struct ec_stripe_head *h)
static struct ec_stripe_head *
__bch2_ec_stripe_head_get(struct btree_trans *trans,
unsigned target,
unsigned disk_label,
unsigned algo,
unsigned redundancy,
enum bch_watermark watermark)
@ -1778,7 +1787,7 @@ __bch2_ec_stripe_head_get(struct btree_trans *trans,
}
list_for_each_entry(h, &c->ec_stripe_head_list, list)
if (h->target == target &&
if (h->disk_label == disk_label &&
h->algo == algo &&
h->redundancy == redundancy &&
h->watermark == watermark) {
@ -1788,7 +1797,7 @@ __bch2_ec_stripe_head_get(struct btree_trans *trans,
goto found;
}
h = ec_new_stripe_head_alloc(c, target, algo, redundancy, watermark);
h = ec_new_stripe_head_alloc(c, disk_label, algo, redundancy, watermark);
found:
if (!IS_ERR_OR_NULL(h) &&
h->nr_active_devs < h->redundancy + 2) {
@ -1884,7 +1893,6 @@ static int new_stripe_alloc_buckets(struct btree_trans *trans, struct ec_stripe_
return 0;
}
/* XXX: doesn't obey target: */
static s64 get_existing_stripe(struct bch_fs *c,
struct ec_stripe_head *head)
{
@ -1907,7 +1915,8 @@ static s64 get_existing_stripe(struct bch_fs *c,
m = genradix_ptr(&c->stripes, stripe_idx);
if (m->algorithm == head->algo &&
if (m->disk_label == head->disk_label &&
m->algorithm == head->algo &&
m->nr_redundant == head->redundancy &&
m->sectors == head->blocksize &&
m->blocks_nonempty < m->nr_blocks - m->nr_redundant &&
@ -2052,9 +2061,19 @@ struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *trans,
struct bch_fs *c = trans->c;
struct ec_stripe_head *h;
bool waiting = false;
unsigned disk_label = 0;
struct target t = target_decode(target);
int ret;
h = __bch2_ec_stripe_head_get(trans, target, algo, redundancy, watermark);
if (t.type == TARGET_GROUP) {
if (t.group > U8_MAX) {
bch_err(c, "cannot create a stripe when disk_label > U8_MAX");
return NULL;
}
disk_label = t.group + 1; /* 0 == no label */
}
h = __bch2_ec_stripe_head_get(trans, disk_label, algo, redundancy, watermark);
if (IS_ERR_OR_NULL(h))
return h;
@ -2259,8 +2278,8 @@ void bch2_new_stripes_to_text(struct printbuf *out, struct bch_fs *c)
mutex_lock(&c->ec_stripe_head_lock);
list_for_each_entry(h, &c->ec_stripe_head_list, list) {
prt_printf(out, "target %u algo %u redundancy %u %s:\n",
h->target, h->algo, h->redundancy,
prt_printf(out, "disk label %u algo %u redundancy %u %s:\n",
h->disk_label, h->algo, h->redundancy,
bch2_watermarks[h->watermark]);
if (h->s)

2
fs/bcachefs/ec.h
View File

@ -188,7 +188,7 @@ struct ec_stripe_head {
struct list_head list;
struct mutex lock;
unsigned target;
unsigned disk_label;
unsigned algo;
unsigned redundancy;
enum bch_watermark watermark;

9
fs/bcachefs/ec_format.h
View File

@ -11,7 +11,14 @@ struct bch_stripe {
__u8 csum_granularity_bits;
__u8 csum_type;
__u8 pad;
/*
* XXX: targets should be 16 bits - fix this if we ever do a stripe_v2
*
* we can manage with this because this only needs to point to a
* disk label, not a target:
*/
__u8 disk_label;
struct bch_extent_ptr ptrs[];
} __packed __aligned(8);

1
fs/bcachefs/ec_types.h
View File

@ -16,6 +16,7 @@ struct stripe {
u8 nr_blocks;
u8 nr_redundant;
u8 blocks_nonempty;
u8 disk_label;
};
struct gc_stripe {