diff options
Diffstat (limited to 'fs/bcachefs/ec.c')
| -rw-r--r-- | fs/bcachefs/ec.c | 1981 |
1 files changed, 1981 insertions, 0 deletions
diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c new file mode 100644 index 000000000000..2a77de18c004 --- /dev/null +++ b/fs/bcachefs/ec.c @@ -0,0 +1,1981 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* erasure coding */ + +#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 "checksum.h" +#include "disk_groups.h" +#include "ec.h" +#include "error.h" +#include "io_read.h" +#include "keylist.h" +#include "recovery.h" +#include "replicas.h" +#include "super-io.h" +#include "util.h" + +#include <linux/sort.h> + +#ifdef __KERNEL__ + +#include <linux/raid/pq.h> +#include <linux/raid/xor.h> + +static void raid5_recov(unsigned disks, unsigned failed_idx, + size_t size, void **data) +{ + unsigned i = 2, nr; + + BUG_ON(failed_idx >= disks); + + swap(data[0], data[failed_idx]); + memcpy(data[0], data[1], size); + + while (i < disks) { + nr = min_t(unsigned, disks - i, MAX_XOR_BLOCKS); + xor_blocks(nr, size, data[0], data + i); + i += nr; + } + + swap(data[0], data[failed_idx]); +} + +static void raid_gen(int nd, int np, size_t size, void **v) +{ + if (np >= 1) + raid5_recov(nd + np, nd, size, v); + if (np >= 2) + raid6_call.gen_syndrome(nd + np, size, v); + BUG_ON(np > 2); +} + +static void raid_rec(int nr, int *ir, int nd, int np, size_t size, void **v) +{ + switch (nr) { + case 0: + break; + case 1: + if (ir[0] < nd + 1) + raid5_recov(nd + 1, ir[0], size, v); + else + raid6_call.gen_syndrome(nd + np, size, v); + break; + case 2: + if (ir[1] < nd) { + /* data+data failure. */ + raid6_2data_recov(nd + np, size, ir[0], ir[1], v); + } else if (ir[0] < nd) { + /* data + p/q failure */ + + if (ir[1] == nd) /* data + p failure */ + raid6_datap_recov(nd + np, size, ir[0], v); + else { /* data + q failure */ + raid5_recov(nd + 1, ir[0], size, v); + raid6_call.gen_syndrome(nd + np, size, v); + } + } else { + raid_gen(nd, np, size, v); + } + break; + default: + BUG(); + } +} + +#else + +#include <raid/raid.h> + +#endif + +struct ec_bio { + struct bch_dev *ca; + struct ec_stripe_buf *buf; + size_t idx; + struct bio bio; +}; + +/* Stripes btree keys: */ + +int bch2_stripe_invalid(struct bch_fs *c, struct bkey_s_c k, + enum bkey_invalid_flags flags, + struct printbuf *err) +{ + const struct bch_stripe *s = bkey_s_c_to_stripe(k).v; + int ret = 0; + + bkey_fsck_err_on(bkey_eq(k.k->p, POS_MIN) || + bpos_gt(k.k->p, POS(0, U32_MAX)), c, err, + stripe_pos_bad, + "stripe at bad pos"); + + bkey_fsck_err_on(bkey_val_u64s(k.k) < stripe_val_u64s(s), c, err, + stripe_val_size_bad, + "incorrect value size (%zu < %u)", + bkey_val_u64s(k.k), stripe_val_u64s(s)); + + ret = bch2_bkey_ptrs_invalid(c, k, flags, err); +fsck_err: + return ret; +} + +void bch2_stripe_to_text(struct printbuf *out, struct bch_fs *c, + struct bkey_s_c k) +{ + const struct bch_stripe *s = bkey_s_c_to_stripe(k).v; + unsigned i, nr_data = s->nr_blocks - s->nr_redundant; + + prt_printf(out, "algo %u sectors %u blocks %u:%u csum %u gran %u", + s->algorithm, + le16_to_cpu(s->sectors), + nr_data, + s->nr_redundant, + s->csum_type, + 1U << s->csum_granularity_bits); + + for (i = 0; i < s->nr_blocks; i++) { + const struct bch_extent_ptr *ptr = s->ptrs + i; + struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev); + u32 offset; + u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset); + + prt_printf(out, " %u:%llu:%u", ptr->dev, b, offset); + if (i < nr_data) + prt_printf(out, "#%u", stripe_blockcount_get(s, i)); + prt_printf(out, " gen %u", ptr->gen); + if (ptr_stale(ca, ptr)) + prt_printf(out, " stale"); + } +} + +/* returns blocknr in stripe that we matched: */ +static const struct bch_extent_ptr *bkey_matches_stripe(struct bch_stripe *s, + struct bkey_s_c k, unsigned *block) +{ + struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k); + const struct bch_extent_ptr *ptr; + unsigned i, nr_data = s->nr_blocks - s->nr_redundant; + + bkey_for_each_ptr(ptrs, ptr) + for (i = 0; i < nr_data; i++) + if (__bch2_ptr_matches_stripe(&s->ptrs[i], ptr, + le16_to_cpu(s->sectors))) { + *block = i; + return ptr; + } + + return NULL; +} + +static bool extent_has_stripe_ptr(struct bkey_s_c k, u64 idx) +{ + switch (k.k->type) { + case KEY_TYPE_extent: { + struct bkey_s_c_extent e = bkey_s_c_to_extent(k); + const union bch_extent_entry *entry; + + extent_for_each_entry(e, entry) + if (extent_entry_type(entry) == + BCH_EXTENT_ENTRY_stripe_ptr && + entry->stripe_ptr.idx == idx) + return true; + + break; + } + } + + return false; +} + +/* Stripe bufs: */ + +static void ec_stripe_buf_exit(struct ec_stripe_buf *buf) +{ + if (buf->key.k.type == KEY_TYPE_stripe) { + struct bkey_i_stripe *s = bkey_i_to_stripe(&buf->key); + unsigned i; + + for (i = 0; i < s->v.nr_blocks; i++) { + kvpfree(buf->data[i], buf->size << 9); + buf->data[i] = NULL; + } + } +} + +/* XXX: this is a non-mempoolified memory allocation: */ +static int ec_stripe_buf_init(struct ec_stripe_buf *buf, + unsigned offset, unsigned size) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned csum_granularity = 1U << v->csum_granularity_bits; + unsigned end = offset + size; + unsigned i; + + BUG_ON(end > le16_to_cpu(v->sectors)); + + offset = round_down(offset, csum_granularity); + end = min_t(unsigned, le16_to_cpu(v->sectors), + round_up(end, csum_granularity)); + + buf->offset = offset; + buf->size = end - offset; + + memset(buf->valid, 0xFF, sizeof(buf->valid)); + + for (i = 0; i < v->nr_blocks; i++) { + buf->data[i] = kvpmalloc(buf->size << 9, GFP_KERNEL); + if (!buf->data[i]) + goto err; + } + + return 0; +err: + ec_stripe_buf_exit(buf); + return -BCH_ERR_ENOMEM_stripe_buf; +} + +/* Checksumming: */ + +static struct bch_csum ec_block_checksum(struct ec_stripe_buf *buf, + unsigned block, unsigned offset) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned csum_granularity = 1 << v->csum_granularity_bits; + unsigned end = buf->offset + buf->size; + unsigned len = min(csum_granularity, end - offset); + + BUG_ON(offset >= end); + BUG_ON(offset < buf->offset); + BUG_ON(offset & (csum_granularity - 1)); + BUG_ON(offset + len != le16_to_cpu(v->sectors) && + (len & (csum_granularity - 1))); + + return bch2_checksum(NULL, v->csum_type, + null_nonce(), + buf->data[block] + ((offset - buf->offset) << 9), + len << 9); +} + +static void ec_generate_checksums(struct ec_stripe_buf *buf) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned i, j, csums_per_device = stripe_csums_per_device(v); + + if (!v->csum_type) + return; + + BUG_ON(buf->offset); + BUG_ON(buf->size != le16_to_cpu(v->sectors)); + + for (i = 0; i < v->nr_blocks; i++) + for (j = 0; j < csums_per_device; j++) + stripe_csum_set(v, i, j, + ec_block_checksum(buf, i, j << v->csum_granularity_bits)); +} + +static void ec_validate_checksums(struct bch_fs *c, struct ec_stripe_buf *buf) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned csum_granularity = 1 << v->csum_granularity_bits; + unsigned i; + + if (!v->csum_type) + return; + + for (i = 0; i < v->nr_blocks; i++) { + unsigned offset = buf->offset; + unsigned end = buf->offset + buf->size; + + if (!test_bit(i, buf->valid)) + continue; + + while (offset < end) { + unsigned j = offset >> v->csum_granularity_bits; + unsigned len = min(csum_granularity, end - offset); + struct bch_csum want = stripe_csum_get(v, i, j); + struct bch_csum got = ec_block_checksum(buf, i, offset); + + if (bch2_crc_cmp(want, got)) { + struct printbuf err = PRINTBUF; + struct bch_dev *ca = bch_dev_bkey_exists(c, v->ptrs[i].dev); + + prt_printf(&err, "stripe checksum error: expected %0llx:%0llx got %0llx:%0llx (type %s)\n", + want.hi, want.lo, + got.hi, got.lo, + bch2_csum_types[v->csum_type]); + prt_printf(&err, " for %ps at %u of\n ", (void *) _RET_IP_, i); + bch2_bkey_val_to_text(&err, c, bkey_i_to_s_c(&buf->key)); + bch_err_ratelimited(ca, "%s", err.buf); + printbuf_exit(&err); + + clear_bit(i, buf->valid); + + bch2_io_error(ca, BCH_MEMBER_ERROR_checksum); + break; + } + + offset += len; + } + } +} + +/* Erasure coding: */ + +static void ec_generate_ec(struct ec_stripe_buf *buf) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned nr_data = v->nr_blocks - v->nr_redundant; + unsigned bytes = le16_to_cpu(v->sectors) << 9; + + raid_gen(nr_data, v->nr_redundant, bytes, buf->data); +} + +static unsigned ec_nr_failed(struct ec_stripe_buf *buf) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + + return v->nr_blocks - bitmap_weight(buf->valid, v->nr_blocks); +} + +static int ec_do_recov(struct bch_fs *c, struct ec_stripe_buf *buf) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned i, failed[BCH_BKEY_PTRS_MAX], nr_failed = 0; + unsigned nr_data = v->nr_blocks - v->nr_redundant; + unsigned bytes = buf->size << 9; + + if (ec_nr_failed(buf) > v->nr_redundant) { + bch_err_ratelimited(c, + "error doing reconstruct read: unable to read enough blocks"); + return -1; + } + + for (i = 0; i < nr_data; i++) + if (!test_bit(i, buf->valid)) + failed[nr_failed++] = i; + + raid_rec(nr_failed, failed, nr_data, v->nr_redundant, bytes, buf->data); + return 0; +} + +/* IO: */ + +static void ec_block_endio(struct bio *bio) +{ + struct ec_bio *ec_bio = container_of(bio, struct ec_bio, bio); + struct bch_stripe *v = &bkey_i_to_stripe(&ec_bio->buf->key)->v; + struct bch_extent_ptr *ptr = &v->ptrs[ec_bio->idx]; + struct bch_dev *ca = ec_bio->ca; + struct closure *cl = bio->bi_private; + + if (bch2_dev_io_err_on(bio->bi_status, ca, + bio_data_dir(bio) + ? BCH_MEMBER_ERROR_write + : BCH_MEMBER_ERROR_read, + "erasure coding %s error: %s", + bio_data_dir(bio) ? "write" : "read", + bch2_blk_status_to_str(bio->bi_status))) + clear_bit(ec_bio->idx, ec_bio->buf->valid); + + if (ptr_stale(ca, ptr)) { + bch_err_ratelimited(ca->fs, + "error %s stripe: stale pointer after io", + bio_data_dir(bio) == READ ? "reading from" : "writing to"); + clear_bit(ec_bio->idx, ec_bio->buf->valid); + } + + bio_put(&ec_bio->bio); + percpu_ref_put(&ca->io_ref); + closure_put(cl); +} + +static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf, + blk_opf_t opf, unsigned idx, struct closure *cl) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&buf->key)->v; + unsigned offset = 0, bytes = buf->size << 9; + struct bch_extent_ptr *ptr = &v->ptrs[idx]; + struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev); + enum bch_data_type data_type = idx < v->nr_blocks - v->nr_redundant + ? BCH_DATA_user + : BCH_DATA_parity; + int rw = op_is_write(opf); + + if (ptr_stale(ca, ptr)) { + bch_err_ratelimited(c, + "error %s stripe: stale pointer", + rw == READ ? "reading from" : "writing to"); + clear_bit(idx, buf->valid); + return; + } + + if (!bch2_dev_get_ioref(ca, rw)) { + clear_bit(idx, buf->valid); + return; + } + + this_cpu_add(ca->io_done->sectors[rw][data_type], buf->size); + + while (offset < bytes) { + unsigned nr_iovecs = min_t(size_t, BIO_MAX_VECS, + DIV_ROUND_UP(bytes, PAGE_SIZE)); + unsigned b = min_t(size_t, bytes - offset, + nr_iovecs << PAGE_SHIFT); + struct ec_bio *ec_bio; + + ec_bio = container_of(bio_alloc_bioset(ca->disk_sb.bdev, + nr_iovecs, + opf, + GFP_KERNEL, + &c->ec_bioset), + struct ec_bio, bio); + + ec_bio->ca = ca; + ec_bio->buf = buf; + ec_bio->idx = idx; + + ec_bio->bio.bi_iter.bi_sector = ptr->offset + buf->offset + (offset >> 9); + ec_bio->bio.bi_end_io = ec_block_endio; + ec_bio->bio.bi_private = cl; + + bch2_bio_map(&ec_bio->bio, buf->data[idx] + offset, b); + + closure_get(cl); + percpu_ref_get(&ca->io_ref); + + submit_bio(&ec_bio->bio); + + offset += b; + } + + percpu_ref_put(&ca->io_ref); +} + +static int get_stripe_key_trans(struct btree_trans *trans, u64 idx, + struct ec_stripe_buf *stripe) +{ + struct btree_iter iter; + struct bkey_s_c k; + int ret; + + k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes, + POS(0, idx), BTREE_ITER_SLOTS); + ret = bkey_err(k); + if (ret) + goto err; + if (k.k->type != KEY_TYPE_stripe) { + ret = -ENOENT; + goto err; + } + bkey_reassemble(&stripe->key, k); +err: + bch2_trans_iter_exit(trans, &iter); + return ret; +} + +/* recovery read path: */ +int bch2_ec_read_extent(struct btree_trans *trans, struct bch_read_bio *rbio) +{ + struct bch_fs *c = trans->c; + struct ec_stripe_buf *buf; + struct closure cl; + struct bch_stripe *v; + unsigned i, offset; + int ret = 0; + + closure_init_stack(&cl); + + BUG_ON(!rbio->pick.has_ec); + + buf = kzalloc(sizeof(*buf), GFP_NOFS); + if (!buf) + return -BCH_ERR_ENOMEM_ec_read_extent; + + ret = lockrestart_do(trans, get_stripe_key_trans(trans, rbio->pick.ec.idx, buf)); + if (ret) { + bch_err_ratelimited(c, + "error doing reconstruct read: error %i looking up stripe", ret); + kfree(buf); + return -EIO; + } + + v = &bkey_i_to_stripe(&buf->key)->v; + + if (!bch2_ptr_matches_stripe(v, rbio->pick)) { + bch_err_ratelimited(c, + "error doing reconstruct read: pointer doesn't match stripe"); + ret = -EIO; + goto err; + } + + offset = rbio->bio.bi_iter.bi_sector - v->ptrs[rbio->pick.ec.block].offset; + if (offset + bio_sectors(&rbio->bio) > le16_to_cpu(v->sectors)) { + bch_err_ratelimited(c, + "error doing reconstruct read: read is bigger than stripe"); + ret = -EIO; + goto err; + } + + ret = ec_stripe_buf_init(buf, offset, bio_sectors(&rbio->bio)); + if (ret) + goto err; + + for (i = 0; i < v->nr_blocks; i++) + ec_block_io(c, buf, REQ_OP_READ, i, &cl); + + closure_sync(&cl); + + if (ec_nr_failed(buf) > v->nr_redundant) { + bch_err_ratelimited(c, + "error doing reconstruct read: unable to read enough blocks"); + ret = -EIO; + goto err; + } + + ec_validate_checksums(c, buf); + + ret = ec_do_recov(c, buf); + if (ret) + goto err; + + memcpy_to_bio(&rbio->bio, rbio->bio.bi_iter, + buf->data[rbio->pick.ec.block] + ((offset - buf->offset) << 9)); +err: + ec_stripe_buf_exit(buf); + kfree(buf); + return ret; +} + +/* stripe bucket accounting: */ + +static int __ec_stripe_mem_alloc(struct bch_fs *c, size_t idx, gfp_t gfp) +{ + ec_stripes_heap n, *h = &c->ec_stripes_heap; + + if (idx >= h->size) { + if (!init_heap(&n, max(1024UL, roundup_pow_of_two(idx + 1)), gfp)) + return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc; + + mutex_lock(&c->ec_stripes_heap_lock); + if (n.size > h->size) { + memcpy(n.data, h->data, h->used * sizeof(h->data[0])); + n.used = h->used; + swap(*h, n); + } + mutex_unlock(&c->ec_stripes_heap_lock); + + free_heap(&n); + } + + if (!genradix_ptr_alloc(&c->stripes, idx, gfp)) + return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc; + + if (c->gc_pos.phase != GC_PHASE_NOT_RUNNING && + !genradix_ptr_alloc(&c->gc_stripes, idx, gfp)) + return -BCH_ERR_ENOMEM_ec_stripe_mem_alloc; + + return 0; +} + +static int ec_stripe_mem_alloc(struct btree_trans *trans, + struct btree_iter *iter) +{ + return allocate_dropping_locks_errcode(trans, + __ec_stripe_mem_alloc(trans->c, iter->pos.offset, _gfp)); +} + +/* + * Hash table of open stripes: + * Stripes that are being created or modified are kept in a hash table, so that + * stripe deletion can skip them. + */ + +static bool __bch2_stripe_is_open(struct bch_fs *c, u64 idx) +{ + unsigned hash = hash_64(idx, ilog2(ARRAY_SIZE(c->ec_stripes_new))); + struct ec_stripe_new *s; + + hlist_for_each_entry(s, &c->ec_stripes_new[hash], hash) + if (s->idx == idx) + return true; + return false; +} + +static bool bch2_stripe_is_open(struct bch_fs *c, u64 idx) +{ + bool ret = false; + + spin_lock(&c->ec_stripes_new_lock); + ret = __bch2_stripe_is_open(c, idx); + spin_unlock(&c->ec_stripes_new_lock); + + return ret; +} + +static bool bch2_try_open_stripe(struct bch_fs *c, + struct ec_stripe_new *s, + u64 idx) +{ + bool ret; + + spin_lock(&c->ec_stripes_new_lock); + ret = !__bch2_stripe_is_open(c, idx); + if (ret) { + unsigned hash = hash_64(idx, ilog2(ARRAY_SIZE(c->ec_stripes_new))); + + s->idx = idx; + hlist_add_head(&s->hash, &c->ec_stripes_new[hash]); + } + spin_unlock(&c->ec_stripes_new_lock); + + return ret; +} + +static void bch2_stripe_close(struct bch_fs *c, struct ec_stripe_new *s) +{ + BUG_ON(!s->idx); + + spin_lock(&c->ec_stripes_new_lock); + hlist_del_init(&s->hash); + spin_unlock(&c->ec_stripes_new_lock); + + s->idx = 0; +} + +/* Heap of all existing stripes, ordered by blocks_nonempty */ + +static u64 stripe_idx_to_delete(struct bch_fs *c) +{ + ec_stripes_heap *h = &c->ec_stripes_heap; + + lockdep_assert_held(&c->ec_stripes_heap_lock); + + if (h->used && + h->data[0].blocks_nonempty == 0 && + !bch2_stripe_is_open(c, h->data[0].idx)) + return h->data[0].idx; + + return 0; +} + +static inline int ec_stripes_heap_cmp(ec_stripes_heap *h, + struct ec_stripe_heap_entry l, + struct ec_stripe_heap_entry r) +{ + return ((l.blocks_nonempty > r.blocks_nonempty) - + (l.blocks_nonempty < r.blocks_nonempty)); +} + +static inline void ec_stripes_heap_set_backpointer(ec_stripes_heap *h, + size_t i) +{ + struct bch_fs *c = container_of(h, struct bch_fs, ec_stripes_heap); + + genradix_ptr(&c->stripes, h->data[i].idx)->heap_idx = i; +} + +static void heap_verify_backpointer(struct bch_fs *c, size_t idx) +{ + ec_stripes_heap *h = &c->ec_stripes_heap; + struct stripe *m = genradix_ptr(&c->stripes, idx); + + BUG_ON(m->heap_idx >= h->used); + BUG_ON(h->data[m->heap_idx].idx != idx); +} + +void bch2_stripes_heap_del(struct bch_fs *c, + struct stripe *m, size_t idx) +{ + mutex_lock(&c->ec_stripes_heap_lock); + heap_verify_backpointer(c, idx); + + heap_del(&c->ec_stripes_heap, m->heap_idx, + ec_stripes_heap_cmp, + ec_stripes_heap_set_backpointer); + mutex_unlock(&c->ec_stripes_heap_lock); +} + +void bch2_stripes_heap_insert(struct bch_fs *c, + struct stripe *m, size_t idx) +{ + mutex_lock(&c->ec_stripes_heap_lock); + BUG_ON(heap_full(&c->ec_stripes_heap)); + + heap_add(&c->ec_stripes_heap, ((struct ec_stripe_heap_entry) { + .idx = idx, + .blocks_nonempty = m->blocks_nonempty, + }), + ec_stripes_heap_cmp, + ec_stripes_heap_set_backpointer); + + heap_verify_backpointer(c, idx); + mutex_unlock(&c->ec_stripes_heap_lock); +} + +void bch2_stripes_heap_update(struct bch_fs *c, + struct stripe *m, size_t idx) +{ + ec_stripes_heap *h = &c->ec_stripes_heap; + bool do_deletes; + size_t i; + + mutex_lock(&c->ec_stripes_heap_lock); + heap_verify_backpointer(c, idx); + + h->data[m->heap_idx].blocks_nonempty = m->blocks_nonempty; + + i = m->heap_idx; + heap_sift_up(h, i, ec_stripes_heap_cmp, + ec_stripes_heap_set_backpointer); + heap_sift_down(h, i, ec_stripes_heap_cmp, + ec_stripes_heap_set_backpointer); + + heap_verify_backpointer(c, idx); + + do_deletes = stripe_idx_to_delete(c) != 0; + mutex_unlock(&c->ec_stripes_heap_lock); + + if (do_deletes) + bch2_do_stripe_deletes(c); +} + +/* stripe deletion */ + +static int ec_stripe_delete(struct btree_trans *trans, u64 idx) +{ + struct bch_fs *c = trans->c; + struct btree_iter iter; + struct bkey_s_c k; + struct bkey_s_c_stripe s; + int ret; + + k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes, POS(0, idx), + BTREE_ITER_INTENT); + ret = bkey_err(k); + if (ret) + goto err; + + if (k.k->type != KEY_TYPE_stripe) { + bch2_fs_inconsistent(c, "attempting to delete nonexistent stripe %llu", idx); + ret = -EINVAL; + goto err; + } + + s = bkey_s_c_to_stripe(k); + for (unsigned i = 0; i < s.v->nr_blocks; i++) + if (stripe_blockcount_get(s.v, i)) { + struct printbuf buf = PRINTBUF; + + bch2_bkey_val_to_text(&buf, c, k); + bch2_fs_inconsistent(c, "attempting to delete nonempty stripe %s", buf.buf); + printbuf_exit(&buf); + ret = -EINVAL; + goto err; + } + + ret = bch2_btree_delete_at(trans, &iter, 0); +err: + bch2_trans_iter_exit(trans, &iter); + return ret; +} + +static void ec_stripe_delete_work(struct work_struct *work) +{ + struct bch_fs *c = + container_of(work, struct bch_fs, ec_stripe_delete_work); + struct btree_trans *trans = bch2_trans_get(c); + int ret; + u64 idx; + + while (1) { + mutex_lock(&c->ec_stripes_heap_lock); + idx = stripe_idx_to_delete(c); + mutex_unlock(&c->ec_stripes_heap_lock); + + if (!idx) + break; + + ret = commit_do(trans, NULL, NULL, BTREE_INSERT_NOFAIL, + ec_stripe_delete(trans, idx)); + if (ret) { + bch_err_fn(c, ret); + break; + } + } + + bch2_trans_put(trans); + + bch2_write_ref_put(c, BCH_WRITE_REF_stripe_delete); +} + +void bch2_do_stripe_deletes(struct bch_fs *c) +{ + if (bch2_write_ref_tryget(c, BCH_WRITE_REF_stripe_delete) && + !queue_work(c->write_ref_wq, &c->ec_stripe_delete_work)) + bch2_write_ref_put(c, BCH_WRITE_REF_stripe_delete); +} + +/* stripe creation: */ + +static int ec_stripe_key_update(struct btree_trans *trans, + struct bkey_i_stripe *new, + bool create) +{ + struct bch_fs *c = trans->c; + struct btree_iter iter; + struct bkey_s_c k; + int ret; + + k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_stripes, + new->k.p, BTREE_ITER_INTENT); + ret = bkey_err(k); + if (ret) + goto err; + + if (k.k->type != (create ? KEY_TYPE_deleted : KEY_TYPE_stripe)) { + bch2_fs_inconsistent(c, "error %s stripe: got existing key type %s", + create ? "creating" : "updating", + bch2_bkey_types[k.k->type]); + ret = -EINVAL; + goto err; + } + + if (k.k->type == KEY_TYPE_stripe) { + const struct bch_stripe *old = bkey_s_c_to_stripe(k).v; + unsigned i; + + if (old->nr_blocks != new->v.nr_blocks) { + bch_err(c, "error updating stripe: nr_blocks does not match"); + ret = -EINVAL; + goto err; + } + + for (i = 0; i < new->v.nr_blocks; i++) { + unsigned v = stripe_blockcount_get(old, i); + + BUG_ON(v && + (old->ptrs[i].dev != new->v.ptrs[i].dev || + old->ptrs[i].gen != new->v.ptrs[i].gen || + old->ptrs[i].offset != new->v.ptrs[i].offset)); + + stripe_blockcount_set(&new->v, i, v); + } + } + + ret = bch2_trans_update(trans, &iter, &new->k_i, 0); +err: + bch2_trans_iter_exit(trans, &iter); + return ret; +} + +static int ec_stripe_update_extent(struct btree_trans *trans, + struct bpos bucket, u8 gen, + struct ec_stripe_buf *s, + struct bpos *bp_pos) +{ + struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v; + 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 bch_extent_stripe_ptr stripe_ptr; + struct bkey_i *n; + int ret, dev, block; + + ret = bch2_get_next_backpointer(trans, bucket, gen, + bp_pos, &bp, BTREE_ITER_CACHED); + if (ret) + return ret; + if (bpos_eq(*bp_pos, SPOS_MAX)) + return 0; + + if (bp.level) { + struct printbuf buf = PRINTBUF; + struct btree_iter node_iter; + struct btree *b; + + b = bch2_backpointer_get_node(trans, &node_iter, *bp_pos, bp); + bch2_trans_iter_exit(trans, &node_iter); + + if (!b) + return 0; + + prt_printf(&buf, "found btree node in erasure coded bucket: b=%px\n", b); + bch2_backpointer_to_text(&buf, &bp); + + bch2_fs_inconsistent(c, "%s", buf.buf); + printbuf_exit(&buf); + return -EIO; + } + + k = bch2_backpointer_get_key(trans, &iter, *bp_pos, bp, BTREE_ITER_INTENT); + 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)) + goto out; + + ptr_c = bkey_matches_stripe(v, k, &block); + /* + * It doesn't generally make sense to erasure code cached ptrs: + * XXX: should we be incrementing a counter? + */ + if (!ptr_c || ptr_c->cached) + goto out; + + dev = v->ptrs[block].dev; + + n = bch2_trans_kmalloc(trans, bkey_bytes(k.k) + sizeof(stripe_ptr)); + ret = PTR_ERR_OR_ZERO(n); + if (ret) + goto out; + + bkey_reassemble(n, k); + + bch2_bkey_drop_ptrs(bkey_i_to_s(n), ptr, ptr->dev != dev); + ec_ptr = bch2_bkey_has_device(bkey_i_to_s(n), dev); + BUG_ON(!ec_ptr); + + stripe_ptr = (struct bch_extent_stripe_ptr) { + .type = 1 << BCH_EXTENT_ENTRY_stripe_ptr, + .block = block, + .redundancy = v->nr_redundant, + .idx = s->key.k.p.offset, + }; + + __extent_entry_insert(n, + (union bch_extent_entry *) ec_ptr, + (union bch_extent_entry *) &stripe_ptr); + + ret = bch2_trans_update(trans, &iter, n, 0); +out: + bch2_trans_iter_exit(trans, &iter); + return ret; +} + +static int ec_stripe_update_bucket(struct btree_trans *trans, struct ec_stripe_buf *s, + unsigned block) +{ + struct bch_fs *c = trans->c; + struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v; + struct bch_extent_ptr bucket = v->ptrs[block]; + struct bpos bucket_pos = PTR_BUCKET_POS(c, &bucket); + struct bpos bp_pos = POS_MIN; + int ret = 0; + + while (1) { + ret = commit_do(trans, NULL, NULL, + BTREE_INSERT_NOCHECK_RW| + BTREE_INSERT_NOFAIL, + ec_stripe_update_extent(trans, bucket_pos, bucket.gen, + s, &bp_pos)); + if (ret) + break; + if (bkey_eq(bp_pos, POS_MAX)) + break; + + bp_pos = bpos_nosnap_successor(bp_pos); + } + + return ret; +} + +static int ec_stripe_update_extents(struct bch_fs *c, struct ec_stripe_buf *s) +{ + struct btree_trans *trans = bch2_trans_get(c); + struct bch_stripe *v = &bkey_i_to_stripe(&s->key)->v; + unsigned i, nr_data = v->nr_blocks - v->nr_redundant; + int ret = 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_put(trans); + + return ret; +} + +static void zero_out_rest_of_ec_bucket(struct bch_fs *c, + struct ec_stripe_new *s, + unsigned block, + struct open_bucket *ob) +{ + struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev); + unsigned offset = ca->mi.bucket_size - ob->sectors_free; + int ret; + + if (!bch2_dev_get_ioref(ca, WRITE)) { + s->err = -BCH_ERR_erofs_no_writes; + return; + } + + memset(s->new_stripe.data[block] + (offset << 9), + 0, + ob->sectors_free << 9); + + ret = blkdev_issue_zeroout(ca->disk_sb.bdev, + ob->bucket * ca->mi.bucket_size + offset, + ob->sectors_free, + GFP_KERNEL, 0); + + percpu_ref_put(&ca->io_ref); + + if (ret) + s->err = ret; +} + +void bch2_ec_stripe_new_free(struct bch_fs *c, struct ec_stripe_new *s) +{ + if (s->idx) + bch2_stripe_close(c, s); + kfree(s); +} + +/* + * data buckets of new stripe all written: create the stripe + */ +static void ec_stripe_create(struct ec_stripe_new *s) +{ + struct bch_fs *c = s->c; + struct open_bucket *ob; + struct bch_stripe *v = &bkey_i_to_stripe(&s->new_stripe.key)->v; + unsigned i, nr_data = v->nr_blocks - v->nr_redundant; + int ret; + + BUG_ON(s->h->s == s); + + closure_sync(&s->iodone); + + if (!s->err) { + for (i = 0; i < nr_data; i++) + if (s->blocks[i]) { + ob = c->open_buckets + s->blocks[i]; + + if (ob->sectors_free) + zero_out_rest_of_ec_bucket(c, s, i, ob); + } + } + + if (s->err) { + if (!bch2_err_matches(s->err, EROFS)) + bch_err(c, "error creating stripe: error writing data buckets"); + goto err; + } + + if (s->have_existing_stripe) { + ec_validate_checksums(c, &s->existing_stripe); + + if (ec_do_recov(c, &s->existing_stripe)) { + bch_err(c, "error creating stripe: error reading existing stripe"); + goto err; + } + + for (i = 0; i < nr_data; i++) + if (stripe_blockcount_get(&bkey_i_to_stripe(&s->existing_stripe.key)->v, i)) + swap(s->new_stripe.data[i], + s->existing_stripe.data[i]); + + ec_stripe_buf_exit(&s->existing_stripe); + } + + BUG_ON(!s->allocated); + BUG_ON(!s->idx); + + ec_generate_ec(&s->new_stripe); + + ec_generate_checksums(&s->new_stripe); + + /* write p/q: */ + for (i = nr_data; i < v->nr_blocks; i++) + ec_block_io(c, &s->new_stripe, REQ_OP_WRITE, i, &s->iodone); + closure_sync(&s->iodone); + + if (ec_nr_failed(&s->new_stripe)) { + bch_err(c, "error creating stripe: error writing redundancy buckets"); + goto err; + } + + ret = bch2_trans_do(c, &s->res, NULL, + BTREE_INSERT_NOCHECK_RW| + BTREE_INSERT_NOFAIL, + ec_stripe_key_update(trans, + bkey_i_to_stripe(&s->new_stripe.key), + !s->have_existing_stripe)); + if (ret) { + bch_err(c, "error creating stripe: error creating stripe key"); + goto err; + } + + ret = ec_stripe_update_extents(c, &s->new_stripe); + if (ret) { + bch_err_msg(c, ret, "creating stripe: error updating pointers"); + goto err; + } +err: + bch2_disk_reservation_put(c, &s->res); + + for (i = 0; i < v->nr_blocks; i++) + if (s->blocks[i]) { + ob = c->open_buckets + s->blocks[i]; + + if (i < nr_data) { + ob->ec = NULL; + __bch2_open_bucket_put(c, ob); + } else { + bch2_open_bucket_put(c, ob); + } + } + + mutex_lock(&c->ec_stripe_new_lock); + list_del(&s->list); + mutex_unlock(&c->ec_stripe_new_lock); + wake_up(&c->ec_stripe_new_wait); + + ec_stripe_buf_exit(&s->existing_stripe); + ec_stripe_buf_exit(&s->new_stripe); + closure_debug_destroy(&s->iodone); + + ec_stripe_new_put(c, s, STRIPE_REF_stripe); +} + +static struct ec_stripe_new *get_pending_stripe(struct bch_fs *c) +{ + struct ec_stripe_new *s; + + mutex_lock(&c->ec_stripe_new_lock); + list_for_each_entry(s, &c->ec_stripe_new_list, list) + if (!atomic_read(&s->ref[STRIPE_REF_io])) + goto out; + s = NULL; +out: + mutex_unlock(&c->ec_stripe_new_lock); + + return s; +} + +static void ec_stripe_create_work(struct work_struct *work) +{ + struct bch_fs *c = container_of(work, + struct bch_fs, ec_stripe_create_work); + struct ec_stripe_new *s; + + while ((s = get_pending_stripe(c))) + ec_stripe_create(s); + + bch2_write_ref_put(c, BCH_WRITE_REF_stripe_create); +} + +void bch2_ec_do_stripe_creates(struct bch_fs *c) +{ + bch2_write_ref_get(c, BCH_WRITE_REF_stripe_create); + + if (!queue_work(system_long_wq, &c->ec_stripe_create_work)) + bch2_write_ref_put(c, BCH_WRITE_REF_stripe_create); +} + +static void ec_stripe_set_pending(struct bch_fs *c, struct ec_stripe_head *h) +{ + struct ec_stripe_new *s = h->s; + + BUG_ON(!s->allocated && !s->err); + + h->s = NULL; + s->pending = true; + + mutex_lock(&c->ec_stripe_new_lock); + list_add(&s->list, &c->ec_stripe_new_list); + mutex_unlock(&c->ec_stripe_new_lock); + + ec_stripe_new_put(c, s, STRIPE_REF_io); +} + +void bch2_ec_bucket_cancel(struct bch_fs *c, struct open_bucket *ob) +{ + struct ec_stripe_new *s = ob->ec; + + s->err = -EIO; +} + +void *bch2_writepoint_ec_buf(struct bch_fs *c, struct write_point *wp) +{ + struct open_bucket *ob = ec_open_bucket(c, &wp->ptrs); + struct bch_dev *ca; + unsigned offset; + + if (!ob) + return NULL; + + BUG_ON(!ob->ec->new_stripe.data[ob->ec_idx]); + + ca = bch_dev_bkey_exists(c, ob->dev); + offset = ca->mi.bucket_size - ob->sectors_free; + + return ob->ec->new_stripe.data[ob->ec_idx] + (offset << 9); +} + +static int unsigned_cmp(const void *_l, const void *_r) +{ + unsigned l = *((const unsigned *) _l); + unsigned r = *((const unsigned *) _r); + + return cmp_int(l, r); +} + +/* pick most common bucket size: */ +static unsigned pick_blocksize(struct bch_fs *c, + struct bch_devs_mask *devs) +{ + struct bch_dev *ca; + unsigned i, nr = 0, sizes[BCH_SB_MEMBERS_MAX]; + struct { + unsigned nr, size; + } cur = { 0, 0 }, best = { 0, 0 }; + + for_each_member_device_rcu(ca, c, i, devs) + sizes[nr++] = ca->mi.bucket_size; + + sort(sizes, nr, sizeof(unsigned), unsigned_cmp, NULL); + + for (i = 0; i < nr; i++) { + if (sizes[i] != cur.size) { + if (cur.nr > best.nr) + best = cur; + + cur.nr = 0; + cur.size = sizes[i]; + } + + cur.nr++; + } + + if (cur.nr > best.nr) + best = cur; + + return best.size; +} + +static bool may_create_new_stripe(struct bch_fs *c) +{ + return false; +} + +static void ec_stripe_key_init(struct bch_fs *c, + struct bkey_i *k, + unsigned nr_data, + unsigned nr_parity, + unsigned stripe_size) +{ + struct bkey_i_stripe *s = bkey_stripe_init(k); + unsigned u64s; + + s->v.sectors = cpu_to_le16(stripe_size); + s->v.algorithm = 0; + s->v.nr_blocks = nr_data + nr_parity; + 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; + + while ((u64s = stripe_val_u64s(&s->v)) > BKEY_VAL_U64s_MAX) { + BUG_ON(1 << s->v.csum_granularity_bits >= + le16_to_cpu(s->v.sectors) || + s->v.csum_granularity_bits == U8_MAX); + s->v.csum_granularity_bits++; + } + + set_bkey_val_u64s(&s->k, u64s); +} + +static int ec_new_stripe_alloc(struct bch_fs *c, struct ec_stripe_head *h) +{ + struct ec_stripe_new *s; + + lockdep_assert_held(&h->lock); + + s = kzalloc(sizeof(*s), GFP_KERNEL); + if (!s) + return -BCH_ERR_ENOMEM_ec_new_stripe_alloc; + + mutex_init(&s->lock); + closure_init(&s->iodone, NULL); + atomic_set(&s->ref[STRIPE_REF_stripe], 1); + atomic_set(&s->ref[STRIPE_REF_io], 1); + s->c = c; + s->h = h; + s->nr_data = min_t(unsigned, h->nr_active_devs, + BCH_BKEY_PTRS_MAX) - h->redundancy; + s->nr_parity = h->redundancy; + + ec_stripe_key_init(c, &s->new_stripe.key, + s->nr_data, s->nr_parity, h->blocksize); + + h->s = s; + return 0; +} + +static struct ec_stripe_head * +ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target, + unsigned algo, unsigned redundancy, + enum bch_watermark watermark) +{ + struct ec_stripe_head *h; + struct bch_dev *ca; + unsigned i; + + h = kzalloc(sizeof(*h), GFP_KERNEL); + if (!h) + return NULL; + + mutex_init(&h->lock); + BUG_ON(!mutex_trylock(&h->lock)); + + h->target = target; + h->algo = algo; + h->redundancy = redundancy; + h->watermark = watermark; + + rcu_read_lock(); + h->devs = target_rw_devs(c, BCH_DATA_user, target); + + for_each_member_device_rcu(ca, c, i, &h->devs) + if (!ca->mi.durability) + __clear_bit(i, h->devs.d); + + h->blocksize = pick_blocksize(c, &h->devs); + + for_each_member_device_rcu(ca, c, i, &h->devs) + if (ca->mi.bucket_size == h->blocksize) + h->nr_active_devs++; + + rcu_read_unlock(); + + /* + * If we only have redundancy + 1 devices, we're better off with just + * replication: + */ + if (h->nr_active_devs < h->redundancy + 2) + bch_err(c, "insufficient devices available to create stripe (have %u, need %u) - mismatched bucket sizes?", + h->nr_active_devs, h->redundancy + 2); + + list_add(&h->list, &c->ec_stripe_head_list); + return h; +} + +void bch2_ec_stripe_head_put(struct bch_fs *c, struct ec_stripe_head *h) +{ + if (h->s && + h->s->allocated && + bitmap_weight(h->s->blocks_allocated, + h->s->nr_data) == h->s->nr_data) + ec_stripe_set_pending(c, h); + + mutex_unlock(&h->lock); +} + +static struct ec_stripe_head * +__bch2_ec_stripe_head_get(struct btree_trans *trans, + unsigned target, + unsigned algo, + unsigned redundancy, + enum bch_watermark watermark) +{ + struct bch_fs *c = trans->c; + struct ec_stripe_head *h; + int ret; + + if (!redundancy) + return NULL; + + ret = bch2_trans_mutex_lock(trans, &c->ec_stripe_head_lock); + if (ret) + return ERR_PTR(ret); + + if (test_bit(BCH_FS_GOING_RO, &c->flags)) { + h = ERR_PTR(-BCH_ERR_erofs_no_writes); + goto found; + } + + list_for_each_entry(h, &c->ec_stripe_head_list, list) + if (h->target == target && + h->algo == algo && + h->redundancy == redundancy && + h->watermark == watermark) { + ret = bch2_trans_mutex_lock(trans, &h->lock); + if (ret) + h = ERR_PTR(ret); + goto found; + } + + h = ec_new_stripe_head_alloc(c, target, algo, redundancy, watermark); +found: + if (!IS_ERR_OR_NULL(h) && + h->nr_active_devs < h->redundancy + 2) { + mutex_unlock(&h->lock); + h = NULL; + } + mutex_unlock(&c->ec_stripe_head_lock); + return h; +} + +static int new_stripe_alloc_buckets(struct btree_trans *trans, struct ec_stripe_head *h, + enum bch_watermark watermark, struct closure *cl) +{ + struct bch_fs *c = trans->c; + struct bch_devs_mask devs = h->devs; + struct open_bucket *ob; + struct open_buckets buckets; + struct bch_stripe *v = &bkey_i_to_stripe(&h->s->new_stripe.key)->v; + unsigned i, j, nr_have_parity = 0, nr_have_data = 0; + bool have_cache = true; + int ret = 0; + + BUG_ON(v->nr_blocks != h->s->nr_data + h->s->nr_parity); + BUG_ON(v->nr_redundant != h->s->nr_parity); + + for_each_set_bit(i, h->s->blocks_gotten, v->nr_blocks) { + __clear_bit(v->ptrs[i].dev, devs.d); + if (i < h->s->nr_data) + nr_have_data++; + else + nr_have_parity++; + } + + BUG_ON(nr_have_data > h->s->nr_data); + BUG_ON(nr_have_parity > h->s->nr_parity); + + buckets.nr = 0; + if (nr_have_parity < h->s->nr_parity) { + ret = bch2_bucket_alloc_set_trans(trans, &buckets, + &h->parity_stripe, + &devs, + h->s->nr_parity, + &nr_have_parity, + &have_cache, 0, + BCH_DATA_parity, + watermark, + cl); + + open_bucket_for_each(c, &buckets, ob, i) { + j = find_next_zero_bit(h->s->blocks_gotten, + h->s->nr_data + h->s->nr_parity, + h->s->nr_data); + BUG_ON(j >= h->s->nr_data + h->s->nr_parity); + + h->s->blocks[j] = buckets.v[i]; + v->ptrs[j] = bch2_ob_ptr(c, ob); + __set_bit(j, h->s->blocks_gotten); + } + + if (ret) + return ret; + } + + buckets.nr = 0; + if (nr_have_data < h->s->nr_data) { + ret = bch2_bucket_alloc_set_trans(trans, &buckets, + &h->block_stripe, + &devs, + h->s->nr_data, + &nr_have_data, + &have_cache, 0, + BCH_DATA_user, + watermark, + cl); + + open_bucket_for_each(c, &buckets, ob, i) { + j = find_next_zero_bit(h->s->blocks_gotten, + h->s->nr_data, 0); + BUG_ON(j >= h->s->nr_data); + + h->s->blocks[j] = buckets.v[i]; + v->ptrs[j] = bch2_ob_ptr(c, ob); + __set_bit(j, h->s->blocks_gotten); + } + + if (ret) + return ret; + } + + return 0; +} + +/* XXX: doesn't obey target: */ +static s64 get_existing_stripe(struct bch_fs *c, + struct ec_stripe_head *head) +{ + ec_stripes_heap *h = &c->ec_stripes_heap; + struct stripe *m; + size_t heap_idx; + u64 stripe_idx; + s64 ret = -1; + + if (may_create_new_stripe(c)) + return -1; + + mutex_lock(&c->ec_stripes_heap_lock); + for (heap_idx = 0; heap_idx < h->used; heap_idx++) { + /* No blocks worth reusing, stripe will just be deleted: */ + if (!h->data[heap_idx].blocks_nonempty) + continue; + + stripe_idx = h->data[heap_idx].idx; + + m = genradix_ptr(&c->stripes, stripe_idx); + + if (m->algorithm == head->algo && + m->nr_redundant == head->redundancy && + m->sectors == head->blocksize && + m->blocks_nonempty < m->nr_blocks - m->nr_redundant && + bch2_try_open_stripe(c, head->s, stripe_idx)) { + ret = stripe_idx; + break; + } + } + mutex_unlock(&c->ec_stripes_heap_lock); + return ret; +} + +static int __bch2_ec_stripe_head_reuse(struct btree_trans *trans, struct ec_stripe_head *h) +{ + struct bch_fs *c = trans->c; + struct bch_stripe *new_v = &bkey_i_to_stripe(&h->s->new_stripe.key)->v; + struct bch_stripe *existing_v; + unsigned i; + s64 idx; + int ret; + + /* + * If we can't allocate a new stripe, and there's no stripes with empty + * blocks for us to reuse, that means we have to wait on copygc: + */ + idx = get_existing_stripe(c, h); + if (idx < 0) + return -BCH_ERR_stripe_alloc_blocked; + + ret = get_stripe_key_trans(trans, idx, &h->s->existing_stripe); + if (ret) { + bch2_stripe_close(c, h->s); + if (!bch2_err_matches(ret, BCH_ERR_transaction_restart)) + bch2_fs_fatal_error(c, "error reading stripe key: %s", bch2_err_str(ret)); + return ret; + } + + existing_v = &bkey_i_to_stripe(&h->s->existing_stripe.key)->v; + + BUG_ON(existing_v->nr_redundant != h->s->nr_parity); + h->s->nr_data = existing_v->nr_blocks - + existing_v->nr_redundant; + + ret = ec_stripe_buf_init(&h->s->existing_stripe, 0, h->blocksize); + if (ret) { + bch2_stripe_close(c, h->s); + return ret; + } + + BUG_ON(h->s->existing_stripe.size != h->blocksize); + BUG_ON(h->s->existing_stripe.size != le16_to_cpu(existing_v->sectors)); + + /* + * Free buckets we initially allocated - they might conflict with + * blocks from the stripe we're reusing: + */ + for_each_set_bit(i, h->s->blocks_gotten, new_v->nr_blocks) { + bch2_open_bucket_put(c, c->open_buckets + h->s->blocks[i]); + h->s->blocks[i] = 0; + } + memset(h->s->blocks_gotten, 0, sizeof(h->s->blocks_gotten)); + memset(h->s->blocks_allocated, 0, sizeof(h->s->blocks_allocated)); + + for (i = 0; i < existing_v->nr_blocks; i++) { + if (stripe_blockcount_get(existing_v, i)) { + __set_bit(i, h->s->blocks_gotten); + __set_bit(i, h->s->blocks_allocated); + } + + ec_block_io(c, &h->s->existing_stripe, READ, i, &h->s->iodone); + } + + bkey_copy(&h->s->new_stripe.key, &h->s->existing_stripe.key); + h->s->have_existing_stripe = true; + + return 0; +} + +static int __bch2_ec_stripe_head_reserve(struct btree_trans *trans, struct ec_stripe_head *h) +{ + struct bch_fs *c = trans->c; + struct btree_iter iter; + struct bkey_s_c k; + struct bpos min_pos = POS(0, 1); + struct bpos start_pos = bpos_max(min_pos, POS(0, c->ec_stripe_hint)); + int ret; + + if (!h->s->res.sectors) { + ret = bch2_disk_reservation_get(c, &h->s->res, + h->blocksize, + h->s->nr_parity, + BCH_DISK_RESERVATION_NOFAIL); + if (ret) + return ret; + } + + for_each_btree_key_norestart(trans, iter, BTREE_ID_stripes, start_pos, + BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) { + if (bkey_gt(k.k->p, POS(0, U32_MAX))) { + if (start_pos.offset) { + start_pos = min_pos; + bch2_btree_iter_set_pos(&iter, start_pos); + continue; + } + + ret = -BCH_ERR_ENOSPC_stripe_create; + break; + } + + if (bkey_deleted(k.k) && + bch2_try_open_stripe(c, h->s, k.k->p.offset)) + break; + } + + c->ec_stripe_hint = iter.pos.offset; + + if (ret) + goto err; + + ret = ec_stripe_mem_alloc(trans, &iter); + if (ret) { + bch2_stripe_close(c, h->s); + goto err; + } + + h->s->new_stripe.key.k.p = iter.pos; +out: + bch2_trans_iter_exit(trans, &iter); + return ret; +err: + bch2_disk_reservation_put(c, &h->s->res); + goto out; +} + +struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *trans, + unsigned target, + unsigned algo, + unsigned redundancy, + enum bch_watermark watermark, + struct closure *cl) +{ + struct bch_fs *c = trans->c; + struct ec_stripe_head *h; + bool waiting = false; + int ret; + + h = __bch2_ec_stripe_head_get(trans, target, algo, redundancy, watermark); + if (IS_ERR_OR_NULL(h)) + return h; + + if (!h->s) { + ret = ec_new_stripe_alloc(c, h); + if (ret) { + bch_err(c, "failed to allocate new stripe"); + goto err; + } + } + + if (h->s->allocated) + goto allocated; + + if (h->s->have_existing_stripe) + goto alloc_existing; + + /* First, try to allocate a full stripe: */ + ret = new_stripe_alloc_buckets(trans, h, BCH_WATERMARK_stripe, NULL) ?: + __bch2_ec_stripe_head_reserve(trans, h); + if (!ret) + goto allocate_buf; + if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || + bch2_err_matches(ret, ENOMEM)) + goto err; + + /* + * Not enough buckets available for a full stripe: we must reuse an + * existing stripe: + */ + while (1) { + ret = __bch2_ec_stripe_head_reuse(trans, h); + if (!ret) + break; + if (waiting || !cl || ret != -BCH_ERR_stripe_alloc_blocked) + goto err; + + if (watermark == BCH_WATERMARK_copygc) { + ret = new_stripe_alloc_buckets(trans, h, watermark, NULL) ?: + __bch2_ec_stripe_head_reserve(trans, h); + if (ret) + goto err; + goto allocate_buf; + } + + /* XXX freelist_wait? */ + closure_wait(&c->freelist_wait, cl); + waiting = true; + } + + if (waiting) + closure_wake_up(&c->freelist_wait); +alloc_existing: + /* + * Retry allocating buckets, with the watermark for this + * particular write: + */ + ret = new_stripe_alloc_buckets(trans, h, watermark, cl); + if (ret) + goto err; + +allocate_buf: + ret = ec_stripe_buf_init(&h->s->new_stripe, 0, h->blocksize); + if (ret) + goto err; + + h->s->allocated = true; +allocated: + BUG_ON(!h->s->idx); + BUG_ON(!h->s->new_stripe.data[0]); + BUG_ON(trans->restarted); + return h; +err: + bch2_ec_stripe_head_put(c, h); + return ERR_PTR(ret); +} + +static void __bch2_ec_stop(struct bch_fs *c, struct bch_dev *ca) +{ + struct ec_stripe_head *h; + struct open_bucket *ob; + unsigned i; + + mutex_lock(&c->ec_stripe_head_lock); + list_for_each_entry(h, &c->ec_stripe_head_list, list) { + mutex_lock(&h->lock); + if (!h->s) + goto unlock; + + if (!ca) + goto found; + + for (i = 0; i < bkey_i_to_stripe(&h->s->new_stripe.key)->v.nr_blocks; i++) { + if (!h->s->blocks[i]) + continue; + + ob = c->open_buckets + h->s->blocks[i]; + if (ob->dev == ca->dev_idx) + goto found; + } + goto unlock; +found: + h->s->err = -BCH_ERR_erofs_no_writes; + ec_stripe_set_pending(c, h); +unlock: + mutex_unlock(&h->lock); + } + mutex_unlock(&c->ec_stripe_head_lock); +} + +void bch2_ec_stop_dev(struct bch_fs *c, struct bch_dev *ca) +{ + __bch2_ec_stop(c, ca); +} + +void bch2_fs_ec_stop(struct bch_fs *c) +{ + __bch2_ec_stop(c, NULL); +} + +static bool bch2_fs_ec_flush_done(struct bch_fs *c) +{ + bool ret; + + mutex_lock(&c->ec_stripe_new_lock); + ret = list_empty(&c->ec_stripe_new_list); + mutex_unlock(&c->ec_stripe_new_lock); + + return ret; +} + +void bch2_fs_ec_flush(struct bch_fs *c) +{ + wait_event(c->ec_stripe_new_wait, bch2_fs_ec_flush_done(c)); +} + +int bch2_stripes_read(struct bch_fs *c) +{ + struct btree_trans *trans = bch2_trans_get(c); + struct btree_iter iter; + struct bkey_s_c k; + const struct bch_stripe *s; + struct stripe *m; + unsigned i; + int ret; + + for_each_btree_key(trans, iter, BTREE_ID_stripes, POS_MIN, + BTREE_ITER_PREFETCH, k, ret) { + if (k.k->type != KEY_TYPE_stripe) + continue; + + ret = __ec_stripe_mem_alloc(c, k.k->p.offset, GFP_KERNEL); + if (ret) + break; + + s = bkey_s_c_to_stripe(k).v; + + m = genradix_ptr(&c->stripes, k.k->p.offset); + m->sectors = le16_to_cpu(s->sectors); + m->algorithm = s->algorithm; + m->nr_blocks = s->nr_blocks; + m->nr_redundant = s->nr_redundant; + m->blocks_nonempty = 0; + + for (i = 0; i < s->nr_blocks; i++) + m->blocks_nonempty += !!stripe_blockcount_get(s, i); + + bch2_stripes_heap_insert(c, m, k.k->p.offset); + } + bch2_trans_iter_exit(trans, &iter); + + bch2_trans_put(trans); + + if (ret) + bch_err_fn(c, ret); + + return ret; +} + +void bch2_stripes_heap_to_text(struct printbuf *out, struct bch_fs *c) +{ + ec_stripes_heap *h = &c->ec_stripes_heap; + struct stripe *m; + size_t i; + + mutex_lock(&c->ec_stripes_heap_lock); + for (i = 0; i < min_t(size_t, h->used, 50); i++) { + m = genradix_ptr(&c->stripes, h->data[i].idx); + + prt_printf(out, "%zu %u/%u+%u", h->data[i].idx, + h->data[i].blocks_nonempty, + m->nr_blocks - m->nr_redundant, + m->nr_redundant); + if (bch2_stripe_is_open(c, h->data[i].idx)) + prt_str(out, " open"); + prt_newline(out); + } + mutex_unlock(&c->ec_stripes_heap_lock); +} + +void bch2_new_stripes_to_text(struct printbuf *out, struct bch_fs *c) +{ + struct ec_stripe_head *h; + struct ec_stripe_new *s; + + 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, + bch2_watermarks[h->watermark]); + + if (h->s) + prt_printf(out, "\tidx %llu blocks %u+%u allocated %u\n", + h->s->idx, h->s->nr_data, h->s->nr_parity, + bitmap_weight(h->s->blocks_allocated, + h->s->nr_data)); + } + mutex_unlock(&c->ec_stripe_head_lock); + + prt_printf(out, "in flight:\n"); + + mutex_lock(&c->ec_stripe_new_lock); + list_for_each_entry(s, &c->ec_stripe_new_list, list) { + prt_printf(out, "\tidx %llu blocks %u+%u ref %u %u %s\n", + s->idx, s->nr_data, s->nr_parity, + atomic_read(&s->ref[STRIPE_REF_io]), + atomic_read(&s->ref[STRIPE_REF_stripe]), + bch2_watermarks[s->h->watermark]); + } + mutex_unlock(&c->ec_stripe_new_lock); +} + +void bch2_fs_ec_exit(struct bch_fs *c) +{ + struct ec_stripe_head *h; + unsigned i; + + while (1) { + mutex_lock(&c->ec_stripe_head_lock); + h = list_first_entry_or_null(&c->ec_stripe_head_list, + struct ec_stripe_head, list); + if (h) + list_del(&h->list); + mutex_unlock(&c->ec_stripe_head_lock); + if (!h) + break; + + if (h->s) { + for (i = 0; i < bkey_i_to_stripe(&h->s->new_stripe.key)->v.nr_blocks; i++) + BUG_ON(h->s->blocks[i]); + + kfree(h->s); + } + kfree(h); + } + + BUG_ON(!list_empty(&c->ec_stripe_new_list)); + + free_heap(&c->ec_stripes_heap); + genradix_free(&c->stripes); + bioset_exit(&c->ec_bioset); +} + +void bch2_fs_ec_init_early(struct bch_fs *c) +{ + spin_lock_init(&c->ec_stripes_new_lock); + mutex_init(&c->ec_stripes_heap_lock); + + INIT_LIST_HEAD(&c->ec_stripe_head_list); + mutex_init(&c->ec_stripe_head_lock); + + INIT_LIST_HEAD(&c->ec_stripe_new_list); + mutex_init(&c->ec_stripe_new_lock); + init_waitqueue_head(&c->ec_stripe_new_wait); + + INIT_WORK(&c->ec_stripe_create_work, ec_stripe_create_work); + INIT_WORK(&c->ec_stripe_delete_work, ec_stripe_delete_work); +} + +int bch2_fs_ec_init(struct bch_fs *c) +{ + return bioset_init(&c->ec_bioset, 1, offsetof(struct ec_bio, bio), + BIOSET_NEED_BVECS); +} |