// SPDX-License-Identifier: GPL-2.0 /* * Some low level IO code, and hacks for various block layer limitations * * Copyright 2010, 2011 Kent Overstreet * Copyright 2012 Google, Inc. */ #include "bcachefs.h" #include "alloc_background.h" #include "alloc_foreground.h" #include "btree_update.h" #include "buckets.h" #include "checksum.h" #include "clock.h" #include "compress.h" #include "data_update.h" #include "disk_groups.h" #include "ec.h" #include "error.h" #include "io_read.h" #include "io_misc.h" #include "io_write.h" #include "subvolume.h" #include "trace.h" #include #ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT static bool bch2_target_congested(struct bch_fs *c, u16 target) { const struct bch_devs_mask *devs; unsigned d, nr = 0, total = 0; u64 now = local_clock(), last; s64 congested; struct bch_dev *ca; if (!target) return false; rcu_read_lock(); devs = bch2_target_to_mask(c, target) ?: &c->rw_devs[BCH_DATA_user]; for_each_set_bit(d, devs->d, BCH_SB_MEMBERS_MAX) { ca = rcu_dereference(c->devs[d]); if (!ca) continue; congested = atomic_read(&ca->congested); last = READ_ONCE(ca->congested_last); if (time_after64(now, last)) congested -= (now - last) >> 12; total += max(congested, 0LL); nr++; } rcu_read_unlock(); return bch2_rand_range(nr * CONGESTED_MAX) < total; } #else static bool bch2_target_congested(struct bch_fs *c, u16 target) { return false; } #endif /* Cache promotion on read */ struct promote_op { struct rcu_head rcu; u64 start_time; struct rhash_head hash; struct bpos pos; struct data_update write; struct bio_vec bi_inline_vecs[]; /* must be last */ }; static const struct rhashtable_params bch_promote_params = { .head_offset = offsetof(struct promote_op, hash), .key_offset = offsetof(struct promote_op, pos), .key_len = sizeof(struct bpos), }; static inline int should_promote(struct bch_fs *c, struct bkey_s_c k, struct bpos pos, struct bch_io_opts opts, unsigned flags) { BUG_ON(!opts.promote_target); if (!(flags & BCH_READ_MAY_PROMOTE)) return -BCH_ERR_nopromote_may_not; if (bch2_bkey_has_target(c, k, opts.promote_target)) return -BCH_ERR_nopromote_already_promoted; if (bkey_extent_is_unwritten(k)) return -BCH_ERR_nopromote_unwritten; if (bch2_target_congested(c, opts.promote_target)) return -BCH_ERR_nopromote_congested; if (rhashtable_lookup_fast(&c->promote_table, &pos, bch_promote_params)) return -BCH_ERR_nopromote_in_flight; return 0; } static void promote_free(struct bch_fs *c, struct promote_op *op) { int ret; bch2_data_update_exit(&op->write); ret = rhashtable_remove_fast(&c->promote_table, &op->hash, bch_promote_params); BUG_ON(ret); bch2_write_ref_put(c, BCH_WRITE_REF_promote); kfree_rcu(op, rcu); } static void promote_done(struct bch_write_op *wop) { struct promote_op *op = container_of(wop, struct promote_op, write.op); struct bch_fs *c = op->write.op.c; bch2_time_stats_update(&c->times[BCH_TIME_data_promote], op->start_time); promote_free(c, op); } static void promote_start(struct promote_op *op, struct bch_read_bio *rbio) { struct bio *bio = &op->write.op.wbio.bio; trace_and_count(op->write.op.c, read_promote, &rbio->bio); /* we now own pages: */ BUG_ON(!rbio->bounce); BUG_ON(rbio->bio.bi_vcnt > bio->bi_max_vecs); memcpy(bio->bi_io_vec, rbio->bio.bi_io_vec, sizeof(struct bio_vec) * rbio->bio.bi_vcnt); swap(bio->bi_vcnt, rbio->bio.bi_vcnt); bch2_data_update_read_done(&op->write, rbio->pick.crc); } static struct promote_op *__promote_alloc(struct btree_trans *trans, enum btree_id btree_id, struct bkey_s_c k, struct bpos pos, struct extent_ptr_decoded *pick, struct bch_io_opts opts, unsigned sectors, struct bch_read_bio **rbio) { struct bch_fs *c = trans->c; struct promote_op *op = NULL; struct bio *bio; unsigned pages = DIV_ROUND_UP(sectors, PAGE_SECTORS); int ret; if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_promote)) return ERR_PTR(-BCH_ERR_nopromote_no_writes); op = kzalloc(struct_size(op, bi_inline_vecs, pages), GFP_KERNEL); if (!op) { ret = -BCH_ERR_nopromote_enomem; goto err; } op->start_time = local_clock(); op->pos = pos; /* * We don't use the mempool here because extents that aren't * checksummed or compressed can be too big for the mempool: */ *rbio = kzalloc(sizeof(struct bch_read_bio) + sizeof(struct bio_vec) * pages, GFP_KERNEL); if (!*rbio) { ret = -BCH_ERR_nopromote_enomem; goto err; } rbio_init(&(*rbio)->bio, opts); bio_init(&(*rbio)->bio, NULL, (*rbio)->bio.bi_inline_vecs, pages, 0); if (bch2_bio_alloc_pages(&(*rbio)->bio, sectors << 9, GFP_KERNEL)) { ret = -BCH_ERR_nopromote_enomem; goto err; } (*rbio)->bounce = true; (*rbio)->split = true; (*rbio)->kmalloc = true; if (rhashtable_lookup_insert_fast(&c->promote_table, &op->hash, bch_promote_params)) { ret = -BCH_ERR_nopromote_in_flight; goto err; } bio = &op->write.op.wbio.bio; bio_init(bio, NULL, bio->bi_inline_vecs, pages, 0); ret = bch2_data_update_init(trans, NULL, NULL, &op->write, writepoint_hashed((unsigned long) current), opts, (struct data_update_opts) { .target = opts.promote_target, .extra_replicas = 1, .write_flags = BCH_WRITE_ALLOC_NOWAIT|BCH_WRITE_CACHED, }, btree_id, k); /* * possible errors: -BCH_ERR_nocow_lock_blocked, * -BCH_ERR_ENOSPC_disk_reservation: */ if (ret) { BUG_ON(rhashtable_remove_fast(&c->promote_table, &op->hash, bch_promote_params)); goto err; } op->write.op.end_io = promote_done; return op; err: if (*rbio) bio_free_pages(&(*rbio)->bio); kfree(*rbio); *rbio = NULL; kfree(op); bch2_write_ref_put(c, BCH_WRITE_REF_promote); return ERR_PTR(ret); } noinline static struct promote_op *promote_alloc(struct btree_trans *trans, struct bvec_iter iter, struct bkey_s_c k, struct extent_ptr_decoded *pick, struct bch_io_opts opts, unsigned flags, struct bch_read_bio **rbio, bool *bounce, bool *read_full) { struct bch_fs *c = trans->c; bool promote_full = *read_full || READ_ONCE(c->promote_whole_extents); /* data might have to be decompressed in the write path: */ unsigned sectors = promote_full ? max(pick->crc.compressed_size, pick->crc.live_size) : bvec_iter_sectors(iter); struct bpos pos = promote_full ? bkey_start_pos(k.k) : POS(k.k->p.inode, iter.bi_sector); struct promote_op *promote; int ret; ret = should_promote(c, k, pos, opts, flags); if (ret) goto nopromote; promote = __promote_alloc(trans, k.k->type == KEY_TYPE_reflink_v ? BTREE_ID_reflink : BTREE_ID_extents, k, pos, pick, opts, sectors, rbio); ret = PTR_ERR_OR_ZERO(promote); if (ret) goto nopromote; *bounce = true; *read_full = promote_full; return promote; nopromote: trace_read_nopromote(c, ret); return NULL; } /* Read */ #define READ_RETRY_AVOID 1 #define READ_RETRY 2 #define READ_ERR 3 enum rbio_context { RBIO_CONTEXT_NULL, RBIO_CONTEXT_HIGHPRI, RBIO_CONTEXT_UNBOUND, }; static inline struct bch_read_bio * bch2_rbio_parent(struct bch_read_bio *rbio) { return rbio->split ? rbio->parent : rbio; } __always_inline static void bch2_rbio_punt(struct bch_read_bio *rbio, work_func_t fn, enum rbio_context context, struct workqueue_struct *wq) { if (context <= rbio->context) { fn(&rbio->work); } else { rbio->work.func = fn; rbio->context = context; queue_work(wq, &rbio->work); } } static inline struct bch_read_bio *bch2_rbio_free(struct bch_read_bio *rbio) { BUG_ON(rbio->bounce && !rbio->split); if (rbio->promote) promote_free(rbio->c, rbio->promote); rbio->promote = NULL; if (rbio->bounce) bch2_bio_free_pages_pool(rbio->c, &rbio->bio); if (rbio->split) { struct bch_read_bio *parent = rbio->parent; if (rbio->kmalloc) kfree(rbio); else bio_put(&rbio->bio); rbio = parent; } return rbio; } /* * Only called on a top level bch_read_bio to complete an entire read request, * not a split: */ static void bch2_rbio_done(struct bch_read_bio *rbio) { if (rbio->start_time) bch2_time_stats_update(&rbio->c->times[BCH_TIME_data_read], rbio->start_time); bio_endio(&rbio->bio); } static void bch2_read_retry_nodecode(struct bch_fs *c, struct bch_read_bio *rbio, struct bvec_iter bvec_iter, struct bch_io_failures *failed, unsigned flags) { struct btree_trans *trans = bch2_trans_get(c); struct btree_iter iter; struct bkey_buf sk; struct bkey_s_c k; int ret; flags &= ~BCH_READ_LAST_FRAGMENT; flags |= BCH_READ_MUST_CLONE; bch2_bkey_buf_init(&sk); bch2_trans_iter_init(trans, &iter, rbio->data_btree, rbio->read_pos, BTREE_ITER_slots); retry: rbio->bio.bi_status = 0; k = bch2_btree_iter_peek_slot(&iter); if (bkey_err(k)) goto err; bch2_bkey_buf_reassemble(&sk, c, k); k = bkey_i_to_s_c(sk.k); bch2_trans_unlock(trans); if (!bch2_bkey_matches_ptr(c, k, rbio->pick.ptr, rbio->data_pos.offset - rbio->pick.crc.offset)) { /* extent we wanted to read no longer exists: */ rbio->hole = true; goto out; } ret = __bch2_read_extent(trans, rbio, bvec_iter, rbio->read_pos, rbio->data_btree, k, 0, failed, flags); if (ret == READ_RETRY) goto retry; if (ret) goto err; out: bch2_rbio_done(rbio); bch2_trans_iter_exit(trans, &iter); bch2_trans_put(trans); bch2_bkey_buf_exit(&sk, c); return; err: rbio->bio.bi_status = BLK_STS_IOERR; goto out; } static void bch2_rbio_retry(struct work_struct *work) { struct bch_read_bio *rbio = container_of(work, struct bch_read_bio, work); struct bch_fs *c = rbio->c; struct bvec_iter iter = rbio->bvec_iter; unsigned flags = rbio->flags; subvol_inum inum = { .subvol = rbio->subvol, .inum = rbio->read_pos.inode, }; struct bch_io_failures failed = { .nr = 0 }; trace_and_count(c, read_retry, &rbio->bio); if (rbio->retry == READ_RETRY_AVOID) bch2_mark_io_failure(&failed, &rbio->pick); rbio->bio.bi_status = 0; rbio = bch2_rbio_free(rbio); flags |= BCH_READ_IN_RETRY; flags &= ~BCH_READ_MAY_PROMOTE; if (flags & BCH_READ_NODECODE) { bch2_read_retry_nodecode(c, rbio, iter, &failed, flags); } else { flags &= ~BCH_READ_LAST_FRAGMENT; flags |= BCH_READ_MUST_CLONE; __bch2_read(c, rbio, iter, inum, &failed, flags); } } static void bch2_rbio_error(struct bch_read_bio *rbio, int retry, blk_status_t error) { rbio->retry = retry; if (rbio->flags & BCH_READ_IN_RETRY) return; if (retry == READ_ERR) { rbio = bch2_rbio_free(rbio); rbio->bio.bi_status = error; bch2_rbio_done(rbio); } else { bch2_rbio_punt(rbio, bch2_rbio_retry, RBIO_CONTEXT_UNBOUND, system_unbound_wq); } } static int __bch2_rbio_narrow_crcs(struct btree_trans *trans, struct bch_read_bio *rbio) { struct bch_fs *c = rbio->c; u64 data_offset = rbio->data_pos.offset - rbio->pick.crc.offset; struct bch_extent_crc_unpacked new_crc; struct btree_iter iter; struct bkey_i *new; struct bkey_s_c k; int ret = 0; if (crc_is_compressed(rbio->pick.crc)) return 0; k = bch2_bkey_get_iter(trans, &iter, rbio->data_btree, rbio->data_pos, BTREE_ITER_slots|BTREE_ITER_intent); if ((ret = bkey_err(k))) goto out; if (bversion_cmp(k.k->version, rbio->version) || !bch2_bkey_matches_ptr(c, k, rbio->pick.ptr, data_offset)) goto out; /* Extent was merged? */ if (bkey_start_offset(k.k) < data_offset || k.k->p.offset > data_offset + rbio->pick.crc.uncompressed_size) goto out; if (bch2_rechecksum_bio(c, &rbio->bio, rbio->version, rbio->pick.crc, NULL, &new_crc, bkey_start_offset(k.k) - data_offset, k.k->size, rbio->pick.crc.csum_type)) { bch_err(c, "error verifying existing checksum while narrowing checksum (memory corruption?)"); ret = 0; goto out; } /* * going to be temporarily appending another checksum entry: */ new = bch2_trans_kmalloc(trans, bkey_bytes(k.k) + sizeof(struct bch_extent_crc128)); if ((ret = PTR_ERR_OR_ZERO(new))) goto out; bkey_reassemble(new, k); if (!bch2_bkey_narrow_crcs(new, new_crc)) goto out; ret = bch2_trans_update(trans, &iter, new, BTREE_UPDATE_internal_snapshot_node); out: bch2_trans_iter_exit(trans, &iter); return ret; } static noinline void bch2_rbio_narrow_crcs(struct bch_read_bio *rbio) { bch2_trans_do(rbio->c, NULL, NULL, BCH_TRANS_COMMIT_no_enospc, __bch2_rbio_narrow_crcs(trans, rbio)); } /* Inner part that may run in process context */ static void __bch2_read_endio(struct work_struct *work) { struct bch_read_bio *rbio = container_of(work, struct bch_read_bio, work); struct bch_fs *c = rbio->c; struct bch_dev *ca = bch_dev_bkey_exists(c, rbio->pick.ptr.dev); struct bio *src = &rbio->bio; struct bio *dst = &bch2_rbio_parent(rbio)->bio; struct bvec_iter dst_iter = rbio->bvec_iter; struct bch_extent_crc_unpacked crc = rbio->pick.crc; struct nonce nonce = extent_nonce(rbio->version, crc); unsigned nofs_flags; struct bch_csum csum; int ret; nofs_flags = memalloc_nofs_save(); /* Reset iterator for checksumming and copying bounced data: */ if (rbio->bounce) { src->bi_iter.bi_size = crc.compressed_size << 9; src->bi_iter.bi_idx = 0; src->bi_iter.bi_bvec_done = 0; } else { src->bi_iter = rbio->bvec_iter; } csum = bch2_checksum_bio(c, crc.csum_type, nonce, src); if (bch2_crc_cmp(csum, rbio->pick.crc.csum) && !c->opts.no_data_io) goto csum_err; /* * XXX * We need to rework the narrow_crcs path to deliver the read completion * first, and then punt to a different workqueue, otherwise we're * holding up reads while doing btree updates which is bad for memory * reclaim. */ if (unlikely(rbio->narrow_crcs)) bch2_rbio_narrow_crcs(rbio); if (rbio->flags & BCH_READ_NODECODE) goto nodecode; /* Adjust crc to point to subset of data we want: */ crc.offset += rbio->offset_into_extent; crc.live_size = bvec_iter_sectors(rbio->bvec_iter); if (crc_is_compressed(crc)) { ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src); if (ret) goto decrypt_err; if (bch2_bio_uncompress(c, src, dst, dst_iter, crc) && !c->opts.no_data_io) goto decompression_err; } else { /* don't need to decrypt the entire bio: */ nonce = nonce_add(nonce, crc.offset << 9); bio_advance(src, crc.offset << 9); BUG_ON(src->bi_iter.bi_size < dst_iter.bi_size); src->bi_iter.bi_size = dst_iter.bi_size; ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src); if (ret) goto decrypt_err; if (rbio->bounce) { struct bvec_iter src_iter = src->bi_iter; bio_copy_data_iter(dst, &dst_iter, src, &src_iter); } } if (rbio->promote) { /* * Re encrypt data we decrypted, so it's consistent with * rbio->crc: */ ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src); if (ret) goto decrypt_err; promote_start(rbio->promote, rbio); rbio->promote = NULL; } nodecode: if (likely(!(rbio->flags & BCH_READ_IN_RETRY))) { rbio = bch2_rbio_free(rbio); bch2_rbio_done(rbio); } out: memalloc_nofs_restore(nofs_flags); return; csum_err: /* * Checksum error: if the bio wasn't bounced, we may have been * reading into buffers owned by userspace (that userspace can * scribble over) - retry the read, bouncing it this time: */ if (!rbio->bounce && (rbio->flags & BCH_READ_USER_MAPPED)) { rbio->flags |= BCH_READ_MUST_BOUNCE; bch2_rbio_error(rbio, READ_RETRY, BLK_STS_IOERR); goto out; } struct printbuf buf = PRINTBUF; buf.atomic++; prt_str(&buf, "data "); bch2_csum_err_msg(&buf, crc.csum_type, rbio->pick.crc.csum, csum); bch_err_inum_offset_ratelimited(ca, rbio->read_pos.inode, rbio->read_pos.offset << 9, "data %s", buf.buf); printbuf_exit(&buf); bch2_io_error(ca, BCH_MEMBER_ERROR_checksum); bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR); goto out; decompression_err: bch_err_inum_offset_ratelimited(c, rbio->read_pos.inode, rbio->read_pos.offset << 9, "decompression error"); bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR); goto out; decrypt_err: bch_err_inum_offset_ratelimited(c, rbio->read_pos.inode, rbio->read_pos.offset << 9, "decrypt error"); bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR); goto out; } static void bch2_read_endio(struct bio *bio) { struct bch_read_bio *rbio = container_of(bio, struct bch_read_bio, bio); struct bch_fs *c = rbio->c; struct bch_dev *ca = bch_dev_bkey_exists(c, rbio->pick.ptr.dev); struct workqueue_struct *wq = NULL; enum rbio_context context = RBIO_CONTEXT_NULL; if (rbio->have_ioref) { bch2_latency_acct(ca, rbio->submit_time, READ); percpu_ref_put(&ca->io_ref); } if (!rbio->split) rbio->bio.bi_end_io = rbio->end_io; if (bch2_dev_inum_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_read, rbio->read_pos.inode, rbio->read_pos.offset, "data read error: %s", bch2_blk_status_to_str(bio->bi_status))) { bch2_rbio_error(rbio, READ_RETRY_AVOID, bio->bi_status); return; } if (((rbio->flags & BCH_READ_RETRY_IF_STALE) && race_fault()) || ptr_stale(ca, &rbio->pick.ptr)) { trace_and_count(c, read_reuse_race, &rbio->bio); if (rbio->flags & BCH_READ_RETRY_IF_STALE) bch2_rbio_error(rbio, READ_RETRY, BLK_STS_AGAIN); else bch2_rbio_error(rbio, READ_ERR, BLK_STS_AGAIN); return; } if (rbio->narrow_crcs || rbio->promote || crc_is_compressed(rbio->pick.crc) || bch2_csum_type_is_encryption(rbio->pick.crc.csum_type)) context = RBIO_CONTEXT_UNBOUND, wq = system_unbound_wq; else if (rbio->pick.crc.csum_type) context = RBIO_CONTEXT_HIGHPRI, wq = system_highpri_wq; bch2_rbio_punt(rbio, __bch2_read_endio, context, wq); } int __bch2_read_indirect_extent(struct btree_trans *trans, unsigned *offset_into_extent, struct bkey_buf *orig_k) { struct btree_iter iter; struct bkey_s_c k; u64 reflink_offset; int ret; reflink_offset = le64_to_cpu(bkey_i_to_reflink_p(orig_k->k)->v.idx) + *offset_into_extent; k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_reflink, POS(0, reflink_offset), 0); ret = bkey_err(k); if (ret) goto err; if (k.k->type != KEY_TYPE_reflink_v && k.k->type != KEY_TYPE_indirect_inline_data) { bch_err_inum_offset_ratelimited(trans->c, orig_k->k->k.p.inode, orig_k->k->k.p.offset << 9, "%llu len %u points to nonexistent indirect extent %llu", orig_k->k->k.p.offset, orig_k->k->k.size, reflink_offset); bch2_inconsistent_error(trans->c); ret = -EIO; goto err; } *offset_into_extent = iter.pos.offset - bkey_start_offset(k.k); bch2_bkey_buf_reassemble(orig_k, trans->c, k); err: bch2_trans_iter_exit(trans, &iter); return ret; } static noinline void read_from_stale_dirty_pointer(struct btree_trans *trans, struct bkey_s_c k, struct bch_extent_ptr ptr) { struct bch_fs *c = trans->c; struct bch_dev *ca = bch_dev_bkey_exists(c, ptr.dev); struct btree_iter iter; struct printbuf buf = PRINTBUF; int ret; bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, PTR_BUCKET_POS(c, &ptr), BTREE_ITER_cached); prt_printf(&buf, "Attempting to read from stale dirty pointer:\n"); printbuf_indent_add(&buf, 2); bch2_bkey_val_to_text(&buf, c, k); prt_newline(&buf); prt_printf(&buf, "memory gen: %u", *bucket_gen(ca, iter.pos.offset)); ret = lockrestart_do(trans, bkey_err(k = bch2_btree_iter_peek_slot(&iter))); if (!ret) { prt_newline(&buf); bch2_bkey_val_to_text(&buf, c, k); } bch2_fs_inconsistent(c, "%s", buf.buf); bch2_trans_iter_exit(trans, &iter); printbuf_exit(&buf); } int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig, struct bvec_iter iter, struct bpos read_pos, enum btree_id data_btree, struct bkey_s_c k, unsigned offset_into_extent, struct bch_io_failures *failed, unsigned flags) { struct bch_fs *c = trans->c; struct extent_ptr_decoded pick; struct bch_read_bio *rbio = NULL; struct bch_dev *ca = NULL; struct promote_op *promote = NULL; bool bounce = false, read_full = false, narrow_crcs = false; struct bpos data_pos = bkey_start_pos(k.k); int pick_ret; if (bkey_extent_is_inline_data(k.k)) { unsigned bytes = min_t(unsigned, iter.bi_size, bkey_inline_data_bytes(k.k)); swap(iter.bi_size, bytes); memcpy_to_bio(&orig->bio, iter, bkey_inline_data_p(k)); swap(iter.bi_size, bytes); bio_advance_iter(&orig->bio, &iter, bytes); zero_fill_bio_iter(&orig->bio, iter); goto out_read_done; } retry_pick: pick_ret = bch2_bkey_pick_read_device(c, k, failed, &pick); /* hole or reservation - just zero fill: */ if (!pick_ret) goto hole; if (pick_ret < 0) { bch_err_inum_offset_ratelimited(c, read_pos.inode, read_pos.offset << 9, "no device to read from"); goto err; } ca = bch_dev_bkey_exists(c, pick.ptr.dev); /* * Stale dirty pointers are treated as IO errors, but @failed isn't * allocated unless we're in the retry path - so if we're not in the * retry path, don't check here, it'll be caught in bch2_read_endio() * and we'll end up in the retry path: */ if ((flags & BCH_READ_IN_RETRY) && !pick.ptr.cached && unlikely(ptr_stale(ca, &pick.ptr))) { read_from_stale_dirty_pointer(trans, k, pick.ptr); bch2_mark_io_failure(failed, &pick); goto retry_pick; } /* * Unlock the iterator while the btree node's lock is still in * cache, before doing the IO: */ bch2_trans_unlock(trans); if (flags & BCH_READ_NODECODE) { /* * can happen if we retry, and the extent we were going to read * has been merged in the meantime: */ if (pick.crc.compressed_size > orig->bio.bi_vcnt * PAGE_SECTORS) goto hole; iter.bi_size = pick.crc.compressed_size << 9; goto get_bio; } if (!(flags & BCH_READ_LAST_FRAGMENT) || bio_flagged(&orig->bio, BIO_CHAIN)) flags |= BCH_READ_MUST_CLONE; narrow_crcs = !(flags & BCH_READ_IN_RETRY) && bch2_can_narrow_extent_crcs(k, pick.crc); if (narrow_crcs && (flags & BCH_READ_USER_MAPPED)) flags |= BCH_READ_MUST_BOUNCE; EBUG_ON(offset_into_extent + bvec_iter_sectors(iter) > k.k->size); if (crc_is_compressed(pick.crc) || (pick.crc.csum_type != BCH_CSUM_none && (bvec_iter_sectors(iter) != pick.crc.uncompressed_size || (bch2_csum_type_is_encryption(pick.crc.csum_type) && (flags & BCH_READ_USER_MAPPED)) || (flags & BCH_READ_MUST_BOUNCE)))) { read_full = true; bounce = true; } if (orig->opts.promote_target) promote = promote_alloc(trans, iter, k, &pick, orig->opts, flags, &rbio, &bounce, &read_full); if (!read_full) { EBUG_ON(crc_is_compressed(pick.crc)); EBUG_ON(pick.crc.csum_type && (bvec_iter_sectors(iter) != pick.crc.uncompressed_size || bvec_iter_sectors(iter) != pick.crc.live_size || pick.crc.offset || offset_into_extent)); data_pos.offset += offset_into_extent; pick.ptr.offset += pick.crc.offset + offset_into_extent; offset_into_extent = 0; pick.crc.compressed_size = bvec_iter_sectors(iter); pick.crc.uncompressed_size = bvec_iter_sectors(iter); pick.crc.offset = 0; pick.crc.live_size = bvec_iter_sectors(iter); } get_bio: if (rbio) { /* * promote already allocated bounce rbio: * promote needs to allocate a bio big enough for uncompressing * data in the write path, but we're not going to use it all * here: */ EBUG_ON(rbio->bio.bi_iter.bi_size < pick.crc.compressed_size << 9); rbio->bio.bi_iter.bi_size = pick.crc.compressed_size << 9; } else if (bounce) { unsigned sectors = pick.crc.compressed_size; rbio = rbio_init(bio_alloc_bioset(NULL, DIV_ROUND_UP(sectors, PAGE_SECTORS), 0, GFP_NOFS, &c->bio_read_split), orig->opts); bch2_bio_alloc_pages_pool(c, &rbio->bio, sectors << 9); rbio->bounce = true; rbio->split = true; } else if (flags & BCH_READ_MUST_CLONE) { /* * Have to clone if there were any splits, due to error * reporting issues (if a split errored, and retrying didn't * work, when it reports the error to its parent (us) we don't * know if the error was from our bio, and we should retry, or * from the whole bio, in which case we don't want to retry and * lose the error) */ rbio = rbio_init(bio_alloc_clone(NULL, &orig->bio, GFP_NOFS, &c->bio_read_split), orig->opts); rbio->bio.bi_iter = iter; rbio->split = true; } else { rbio = orig; rbio->bio.bi_iter = iter; EBUG_ON(bio_flagged(&rbio->bio, BIO_CHAIN)); } EBUG_ON(bio_sectors(&rbio->bio) != pick.crc.compressed_size); rbio->c = c; rbio->submit_time = local_clock(); if (rbio->split) rbio->parent = orig; else rbio->end_io = orig->bio.bi_end_io; rbio->bvec_iter = iter; rbio->offset_into_extent= offset_into_extent; rbio->flags = flags; rbio->have_ioref = pick_ret > 0 && bch2_dev_get_ioref(ca, READ); rbio->narrow_crcs = narrow_crcs; rbio->hole = 0; rbio->retry = 0; rbio->context = 0; /* XXX: only initialize this if needed */ rbio->devs_have = bch2_bkey_devs(k); rbio->pick = pick; rbio->subvol = orig->subvol; rbio->read_pos = read_pos; rbio->data_btree = data_btree; rbio->data_pos = data_pos; rbio->version = k.k->version; rbio->promote = promote; INIT_WORK(&rbio->work, NULL); rbio->bio.bi_opf = orig->bio.bi_opf; rbio->bio.bi_iter.bi_sector = pick.ptr.offset; rbio->bio.bi_end_io = bch2_read_endio; if (rbio->bounce) trace_and_count(c, read_bounce, &rbio->bio); this_cpu_add(c->counters[BCH_COUNTER_io_read], bio_sectors(&rbio->bio)); bch2_increment_clock(c, bio_sectors(&rbio->bio), READ); /* * If it's being moved internally, we don't want to flag it as a cache * hit: */ if (pick.ptr.cached && !(flags & BCH_READ_NODECODE)) bch2_bucket_io_time_reset(trans, pick.ptr.dev, PTR_BUCKET_NR(ca, &pick.ptr), READ); if (!(flags & (BCH_READ_IN_RETRY|BCH_READ_LAST_FRAGMENT))) { bio_inc_remaining(&orig->bio); trace_and_count(c, read_split, &orig->bio); } if (!rbio->pick.idx) { if (!rbio->have_ioref) { bch_err_inum_offset_ratelimited(c, read_pos.inode, read_pos.offset << 9, "no device to read from"); bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR); goto out; } this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_user], bio_sectors(&rbio->bio)); bio_set_dev(&rbio->bio, ca->disk_sb.bdev); if (unlikely(c->opts.no_data_io)) { if (likely(!(flags & BCH_READ_IN_RETRY))) bio_endio(&rbio->bio); } else { if (likely(!(flags & BCH_READ_IN_RETRY))) submit_bio(&rbio->bio); else submit_bio_wait(&rbio->bio); } /* * We just submitted IO which may block, we expect relock fail * events and shouldn't count them: */ trans->notrace_relock_fail = true; } else { /* Attempting reconstruct read: */ if (bch2_ec_read_extent(trans, rbio)) { bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR); goto out; } if (likely(!(flags & BCH_READ_IN_RETRY))) bio_endio(&rbio->bio); } out: if (likely(!(flags & BCH_READ_IN_RETRY))) { return 0; } else { int ret; rbio->context = RBIO_CONTEXT_UNBOUND; bch2_read_endio(&rbio->bio); ret = rbio->retry; rbio = bch2_rbio_free(rbio); if (ret == READ_RETRY_AVOID) { bch2_mark_io_failure(failed, &pick); ret = READ_RETRY; } if (!ret) goto out_read_done; return ret; } err: if (flags & BCH_READ_IN_RETRY) return READ_ERR; orig->bio.bi_status = BLK_STS_IOERR; goto out_read_done; hole: /* * won't normally happen in the BCH_READ_NODECODE * (bch2_move_extent()) path, but if we retry and the extent we wanted * to read no longer exists we have to signal that: */ if (flags & BCH_READ_NODECODE) orig->hole = true; zero_fill_bio_iter(&orig->bio, iter); out_read_done: if (flags & BCH_READ_LAST_FRAGMENT) bch2_rbio_done(orig); return 0; } void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio, struct bvec_iter bvec_iter, subvol_inum inum, struct bch_io_failures *failed, unsigned flags) { struct btree_trans *trans = bch2_trans_get(c); struct btree_iter iter; struct bkey_buf sk; struct bkey_s_c k; u32 snapshot; int ret; BUG_ON(flags & BCH_READ_NODECODE); bch2_bkey_buf_init(&sk); retry: bch2_trans_begin(trans); iter = (struct btree_iter) { NULL }; ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot); if (ret) goto err; bch2_trans_iter_init(trans, &iter, BTREE_ID_extents, SPOS(inum.inum, bvec_iter.bi_sector, snapshot), BTREE_ITER_slots); while (1) { unsigned bytes, sectors, offset_into_extent; enum btree_id data_btree = BTREE_ID_extents; /* * read_extent -> io_time_reset may cause a transaction restart * without returning an error, we need to check for that here: */ ret = bch2_trans_relock(trans); if (ret) break; bch2_btree_iter_set_pos(&iter, POS(inum.inum, bvec_iter.bi_sector)); k = bch2_btree_iter_peek_slot(&iter); ret = bkey_err(k); if (ret) break; offset_into_extent = iter.pos.offset - bkey_start_offset(k.k); sectors = k.k->size - offset_into_extent; bch2_bkey_buf_reassemble(&sk, c, k); ret = bch2_read_indirect_extent(trans, &data_btree, &offset_into_extent, &sk); if (ret) break; k = bkey_i_to_s_c(sk.k); /* * With indirect extents, the amount of data to read is the min * of the original extent and the indirect extent: */ sectors = min(sectors, k.k->size - offset_into_extent); bytes = min(sectors, bvec_iter_sectors(bvec_iter)) << 9; swap(bvec_iter.bi_size, bytes); if (bvec_iter.bi_size == bytes) flags |= BCH_READ_LAST_FRAGMENT; ret = __bch2_read_extent(trans, rbio, bvec_iter, iter.pos, data_btree, k, offset_into_extent, failed, flags); if (ret) break; if (flags & BCH_READ_LAST_FRAGMENT) break; swap(bvec_iter.bi_size, bytes); bio_advance_iter(&rbio->bio, &bvec_iter, bytes); ret = btree_trans_too_many_iters(trans); if (ret) break; } err: bch2_trans_iter_exit(trans, &iter); if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || ret == READ_RETRY || ret == READ_RETRY_AVOID) goto retry; bch2_trans_put(trans); bch2_bkey_buf_exit(&sk, c); if (ret) { bch_err_inum_offset_ratelimited(c, inum.inum, bvec_iter.bi_sector << 9, "read error %i from btree lookup", ret); rbio->bio.bi_status = BLK_STS_IOERR; bch2_rbio_done(rbio); } } void bch2_fs_io_read_exit(struct bch_fs *c) { if (c->promote_table.tbl) rhashtable_destroy(&c->promote_table); bioset_exit(&c->bio_read_split); bioset_exit(&c->bio_read); } int bch2_fs_io_read_init(struct bch_fs *c) { if (bioset_init(&c->bio_read, 1, offsetof(struct bch_read_bio, bio), BIOSET_NEED_BVECS)) return -BCH_ERR_ENOMEM_bio_read_init; if (bioset_init(&c->bio_read_split, 1, offsetof(struct bch_read_bio, bio), BIOSET_NEED_BVECS)) return -BCH_ERR_ENOMEM_bio_read_split_init; if (rhashtable_init(&c->promote_table, &bch_promote_params)) return -BCH_ERR_ENOMEM_promote_table_init; return 0; }