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-rw-r--r--fs/bcachefs/ec.c1981
1 files changed, 1981 insertions, 0 deletions
diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c
new file mode 100644
index 0000000000..2a77de18c0
--- /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);
+}