From f5baaf48e3e82b1caf9f5cd1207d4d6feba3a2e5 Mon Sep 17 00:00:00 2001 From: Thomas Bertschinger Date: Mon, 15 Jan 2024 23:41:02 -0700 Subject: move Rust sources to top level, C sources into c_src This moves the Rust sources out of rust_src/ and into the top level. Running the bcachefs executable out of the development tree is now: $ ./target/release/bcachefs command or $ cargo run --profile release -- command instead of "./bcachefs command". Building and installing is still: $ make && make install Signed-off-by: Thomas Bertschinger Signed-off-by: Kent Overstreet --- c_src/libbcachefs/io_write.c | 1662 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1662 insertions(+) create mode 100644 c_src/libbcachefs/io_write.c (limited to 'c_src/libbcachefs/io_write.c') diff --git a/c_src/libbcachefs/io_write.c b/c_src/libbcachefs/io_write.c new file mode 100644 index 00000000..33c0e783 --- /dev/null +++ b/c_src/libbcachefs/io_write.c @@ -0,0 +1,1662 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2010, 2011 Kent Overstreet + * Copyright 2012 Google, Inc. + */ + +#include "bcachefs.h" +#include "alloc_foreground.h" +#include "bkey_buf.h" +#include "bset.h" +#include "btree_update.h" +#include "buckets.h" +#include "checksum.h" +#include "clock.h" +#include "compress.h" +#include "debug.h" +#include "ec.h" +#include "error.h" +#include "extent_update.h" +#include "inode.h" +#include "io_write.h" +#include "journal.h" +#include "keylist.h" +#include "move.h" +#include "nocow_locking.h" +#include "rebalance.h" +#include "subvolume.h" +#include "super.h" +#include "super-io.h" +#include "trace.h" + +#include +#include +#include +#include + +#ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT + +static inline void bch2_congested_acct(struct bch_dev *ca, u64 io_latency, + u64 now, int rw) +{ + u64 latency_capable = + ca->io_latency[rw].quantiles.entries[QUANTILE_IDX(1)].m; + /* ideally we'd be taking into account the device's variance here: */ + u64 latency_threshold = latency_capable << (rw == READ ? 2 : 3); + s64 latency_over = io_latency - latency_threshold; + + if (latency_threshold && latency_over > 0) { + /* + * bump up congested by approximately latency_over * 4 / + * latency_threshold - we don't need much accuracy here so don't + * bother with the divide: + */ + if (atomic_read(&ca->congested) < CONGESTED_MAX) + atomic_add(latency_over >> + max_t(int, ilog2(latency_threshold) - 2, 0), + &ca->congested); + + ca->congested_last = now; + } else if (atomic_read(&ca->congested) > 0) { + atomic_dec(&ca->congested); + } +} + +void bch2_latency_acct(struct bch_dev *ca, u64 submit_time, int rw) +{ + atomic64_t *latency = &ca->cur_latency[rw]; + u64 now = local_clock(); + u64 io_latency = time_after64(now, submit_time) + ? now - submit_time + : 0; + u64 old, new, v = atomic64_read(latency); + + do { + old = v; + + /* + * If the io latency was reasonably close to the current + * latency, skip doing the update and atomic operation - most of + * the time: + */ + if (abs((int) (old - io_latency)) < (old >> 1) && + now & ~(~0U << 5)) + break; + + new = ewma_add(old, io_latency, 5); + } while ((v = atomic64_cmpxchg(latency, old, new)) != old); + + bch2_congested_acct(ca, io_latency, now, rw); + + __bch2_time_stats_update(&ca->io_latency[rw], submit_time, now); +} + +#endif + +/* Allocate, free from mempool: */ + +void bch2_bio_free_pages_pool(struct bch_fs *c, struct bio *bio) +{ + struct bvec_iter_all iter; + struct bio_vec *bv; + + bio_for_each_segment_all(bv, bio, iter) + if (bv->bv_page != ZERO_PAGE(0)) + mempool_free(bv->bv_page, &c->bio_bounce_pages); + bio->bi_vcnt = 0; +} + +static struct page *__bio_alloc_page_pool(struct bch_fs *c, bool *using_mempool) +{ + struct page *page; + + if (likely(!*using_mempool)) { + page = alloc_page(GFP_NOFS); + if (unlikely(!page)) { + mutex_lock(&c->bio_bounce_pages_lock); + *using_mempool = true; + goto pool_alloc; + + } + } else { +pool_alloc: + page = mempool_alloc(&c->bio_bounce_pages, GFP_NOFS); + } + + return page; +} + +void bch2_bio_alloc_pages_pool(struct bch_fs *c, struct bio *bio, + size_t size) +{ + bool using_mempool = false; + + while (size) { + struct page *page = __bio_alloc_page_pool(c, &using_mempool); + unsigned len = min_t(size_t, PAGE_SIZE, size); + + BUG_ON(!bio_add_page(bio, page, len, 0)); + size -= len; + } + + if (using_mempool) + mutex_unlock(&c->bio_bounce_pages_lock); +} + +/* Extent update path: */ + +int bch2_sum_sector_overwrites(struct btree_trans *trans, + struct btree_iter *extent_iter, + struct bkey_i *new, + bool *usage_increasing, + s64 *i_sectors_delta, + s64 *disk_sectors_delta) +{ + struct bch_fs *c = trans->c; + struct btree_iter iter; + struct bkey_s_c old; + unsigned new_replicas = bch2_bkey_replicas(c, bkey_i_to_s_c(new)); + bool new_compressed = bch2_bkey_sectors_compressed(bkey_i_to_s_c(new)); + int ret = 0; + + *usage_increasing = false; + *i_sectors_delta = 0; + *disk_sectors_delta = 0; + + bch2_trans_copy_iter(&iter, extent_iter); + + for_each_btree_key_upto_continue_norestart(iter, + new->k.p, BTREE_ITER_SLOTS, old, ret) { + s64 sectors = min(new->k.p.offset, old.k->p.offset) - + max(bkey_start_offset(&new->k), + bkey_start_offset(old.k)); + + *i_sectors_delta += sectors * + (bkey_extent_is_allocation(&new->k) - + bkey_extent_is_allocation(old.k)); + + *disk_sectors_delta += sectors * bch2_bkey_nr_ptrs_allocated(bkey_i_to_s_c(new)); + *disk_sectors_delta -= new->k.p.snapshot == old.k->p.snapshot + ? sectors * bch2_bkey_nr_ptrs_fully_allocated(old) + : 0; + + if (!*usage_increasing && + (new->k.p.snapshot != old.k->p.snapshot || + new_replicas > bch2_bkey_replicas(c, old) || + (!new_compressed && bch2_bkey_sectors_compressed(old)))) + *usage_increasing = true; + + if (bkey_ge(old.k->p, new->k.p)) + break; + } + + bch2_trans_iter_exit(trans, &iter); + return ret; +} + +static inline int bch2_extent_update_i_size_sectors(struct btree_trans *trans, + struct btree_iter *extent_iter, + u64 new_i_size, + s64 i_sectors_delta) +{ + struct btree_iter iter; + struct bkey_i *k; + struct bkey_i_inode_v3 *inode; + /* + * Crazy performance optimization: + * Every extent update needs to also update the inode: the inode trigger + * will set bi->journal_seq to the journal sequence number of this + * transaction - for fsync. + * + * But if that's the only reason we're updating the inode (we're not + * updating bi_size or bi_sectors), then we don't need the inode update + * to be journalled - if we crash, the bi_journal_seq update will be + * lost, but that's fine. + */ + unsigned inode_update_flags = BTREE_UPDATE_NOJOURNAL; + int ret; + + k = bch2_bkey_get_mut_noupdate(trans, &iter, BTREE_ID_inodes, + SPOS(0, + extent_iter->pos.inode, + extent_iter->snapshot), + BTREE_ITER_CACHED); + ret = PTR_ERR_OR_ZERO(k); + if (unlikely(ret)) + return ret; + + if (unlikely(k->k.type != KEY_TYPE_inode_v3)) { + k = bch2_inode_to_v3(trans, k); + ret = PTR_ERR_OR_ZERO(k); + if (unlikely(ret)) + goto err; + } + + inode = bkey_i_to_inode_v3(k); + + if (!(le64_to_cpu(inode->v.bi_flags) & BCH_INODE_i_size_dirty) && + new_i_size > le64_to_cpu(inode->v.bi_size)) { + inode->v.bi_size = cpu_to_le64(new_i_size); + inode_update_flags = 0; + } + + if (i_sectors_delta) { + le64_add_cpu(&inode->v.bi_sectors, i_sectors_delta); + inode_update_flags = 0; + } + + if (inode->k.p.snapshot != iter.snapshot) { + inode->k.p.snapshot = iter.snapshot; + inode_update_flags = 0; + } + + ret = bch2_trans_update(trans, &iter, &inode->k_i, + BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE| + inode_update_flags); +err: + bch2_trans_iter_exit(trans, &iter); + return ret; +} + +int bch2_extent_update(struct btree_trans *trans, + subvol_inum inum, + struct btree_iter *iter, + struct bkey_i *k, + struct disk_reservation *disk_res, + u64 new_i_size, + s64 *i_sectors_delta_total, + bool check_enospc) +{ + struct bpos next_pos; + bool usage_increasing; + s64 i_sectors_delta = 0, disk_sectors_delta = 0; + int ret; + + /* + * This traverses us the iterator without changing iter->path->pos to + * search_key() (which is pos + 1 for extents): we want there to be a + * path already traversed at iter->pos because + * bch2_trans_extent_update() will use it to attempt extent merging + */ + ret = __bch2_btree_iter_traverse(iter); + if (ret) + return ret; + + ret = bch2_extent_trim_atomic(trans, iter, k); + if (ret) + return ret; + + next_pos = k->k.p; + + ret = bch2_sum_sector_overwrites(trans, iter, k, + &usage_increasing, + &i_sectors_delta, + &disk_sectors_delta); + if (ret) + return ret; + + if (disk_res && + disk_sectors_delta > (s64) disk_res->sectors) { + ret = bch2_disk_reservation_add(trans->c, disk_res, + disk_sectors_delta - disk_res->sectors, + !check_enospc || !usage_increasing + ? BCH_DISK_RESERVATION_NOFAIL : 0); + if (ret) + return ret; + } + + /* + * Note: + * We always have to do an inode update - even when i_size/i_sectors + * aren't changing - for fsync to work properly; fsync relies on + * inode->bi_journal_seq which is updated by the trigger code: + */ + ret = bch2_extent_update_i_size_sectors(trans, iter, + min(k->k.p.offset << 9, new_i_size), + i_sectors_delta) ?: + bch2_trans_update(trans, iter, k, 0) ?: + bch2_trans_commit(trans, disk_res, NULL, + BCH_TRANS_COMMIT_no_check_rw| + BCH_TRANS_COMMIT_no_enospc); + if (unlikely(ret)) + return ret; + + if (i_sectors_delta_total) + *i_sectors_delta_total += i_sectors_delta; + bch2_btree_iter_set_pos(iter, next_pos); + return 0; +} + +static int bch2_write_index_default(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + struct bkey_buf sk; + struct keylist *keys = &op->insert_keys; + struct bkey_i *k = bch2_keylist_front(keys); + struct btree_trans *trans = bch2_trans_get(c); + struct btree_iter iter; + subvol_inum inum = { + .subvol = op->subvol, + .inum = k->k.p.inode, + }; + int ret; + + BUG_ON(!inum.subvol); + + bch2_bkey_buf_init(&sk); + + do { + bch2_trans_begin(trans); + + k = bch2_keylist_front(keys); + bch2_bkey_buf_copy(&sk, c, k); + + ret = bch2_subvolume_get_snapshot(trans, inum.subvol, + &sk.k->k.p.snapshot); + if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) + continue; + if (ret) + break; + + bch2_trans_iter_init(trans, &iter, BTREE_ID_extents, + bkey_start_pos(&sk.k->k), + BTREE_ITER_SLOTS|BTREE_ITER_INTENT); + + ret = bch2_bkey_set_needs_rebalance(c, sk.k, + op->opts.background_target, + op->opts.background_compression) ?: + bch2_extent_update(trans, inum, &iter, sk.k, + &op->res, + op->new_i_size, &op->i_sectors_delta, + op->flags & BCH_WRITE_CHECK_ENOSPC); + bch2_trans_iter_exit(trans, &iter); + + if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) + continue; + if (ret) + break; + + if (bkey_ge(iter.pos, k->k.p)) + bch2_keylist_pop_front(&op->insert_keys); + else + bch2_cut_front(iter.pos, k); + } while (!bch2_keylist_empty(keys)); + + bch2_trans_put(trans); + bch2_bkey_buf_exit(&sk, c); + + return ret; +} + +/* Writes */ + +void bch2_submit_wbio_replicas(struct bch_write_bio *wbio, struct bch_fs *c, + enum bch_data_type type, + const struct bkey_i *k, + bool nocow) +{ + struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(k)); + struct bch_write_bio *n; + + BUG_ON(c->opts.nochanges); + + bkey_for_each_ptr(ptrs, ptr) { + BUG_ON(!bch2_dev_exists2(c, ptr->dev)); + + struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev); + + if (to_entry(ptr + 1) < ptrs.end) { + n = to_wbio(bio_alloc_clone(NULL, &wbio->bio, + GFP_NOFS, &ca->replica_set)); + + n->bio.bi_end_io = wbio->bio.bi_end_io; + n->bio.bi_private = wbio->bio.bi_private; + n->parent = wbio; + n->split = true; + n->bounce = false; + n->put_bio = true; + n->bio.bi_opf = wbio->bio.bi_opf; + bio_inc_remaining(&wbio->bio); + } else { + n = wbio; + n->split = false; + } + + n->c = c; + n->dev = ptr->dev; + n->have_ioref = nocow || bch2_dev_get_ioref(ca, + type == BCH_DATA_btree ? READ : WRITE); + n->nocow = nocow; + n->submit_time = local_clock(); + n->inode_offset = bkey_start_offset(&k->k); + n->bio.bi_iter.bi_sector = ptr->offset; + + if (likely(n->have_ioref)) { + this_cpu_add(ca->io_done->sectors[WRITE][type], + bio_sectors(&n->bio)); + + bio_set_dev(&n->bio, ca->disk_sb.bdev); + + if (type != BCH_DATA_btree && unlikely(c->opts.no_data_io)) { + bio_endio(&n->bio); + continue; + } + + submit_bio(&n->bio); + } else { + n->bio.bi_status = BLK_STS_REMOVED; + bio_endio(&n->bio); + } + } +} + +static void __bch2_write(struct bch_write_op *); + +static void bch2_write_done(struct closure *cl) +{ + struct bch_write_op *op = container_of(cl, struct bch_write_op, cl); + struct bch_fs *c = op->c; + + EBUG_ON(op->open_buckets.nr); + + bch2_time_stats_update(&c->times[BCH_TIME_data_write], op->start_time); + bch2_disk_reservation_put(c, &op->res); + + if (!(op->flags & BCH_WRITE_MOVE)) + bch2_write_ref_put(c, BCH_WRITE_REF_write); + bch2_keylist_free(&op->insert_keys, op->inline_keys); + + EBUG_ON(cl->parent); + closure_debug_destroy(cl); + if (op->end_io) + op->end_io(op); +} + +static noinline int bch2_write_drop_io_error_ptrs(struct bch_write_op *op) +{ + struct keylist *keys = &op->insert_keys; + struct bch_extent_ptr *ptr; + struct bkey_i *src, *dst = keys->keys, *n; + + for (src = keys->keys; src != keys->top; src = n) { + n = bkey_next(src); + + if (bkey_extent_is_direct_data(&src->k)) { + bch2_bkey_drop_ptrs(bkey_i_to_s(src), ptr, + test_bit(ptr->dev, op->failed.d)); + + if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(src))) + return -EIO; + } + + if (dst != src) + memmove_u64s_down(dst, src, src->k.u64s); + dst = bkey_next(dst); + } + + keys->top = dst; + return 0; +} + +/** + * __bch2_write_index - after a write, update index to point to new data + * @op: bch_write_op to process + */ +static void __bch2_write_index(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + struct keylist *keys = &op->insert_keys; + unsigned dev; + int ret = 0; + + if (unlikely(op->flags & BCH_WRITE_IO_ERROR)) { + ret = bch2_write_drop_io_error_ptrs(op); + if (ret) + goto err; + } + + if (!bch2_keylist_empty(keys)) { + u64 sectors_start = keylist_sectors(keys); + + ret = !(op->flags & BCH_WRITE_MOVE) + ? bch2_write_index_default(op) + : bch2_data_update_index_update(op); + + BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart)); + BUG_ON(keylist_sectors(keys) && !ret); + + op->written += sectors_start - keylist_sectors(keys); + + if (ret && !bch2_err_matches(ret, EROFS)) { + struct bkey_i *insert = bch2_keylist_front(&op->insert_keys); + + bch_err_inum_offset_ratelimited(c, + insert->k.p.inode, insert->k.p.offset << 9, + "write error while doing btree update: %s", + bch2_err_str(ret)); + } + + if (ret) + goto err; + } +out: + /* If some a bucket wasn't written, we can't erasure code it: */ + for_each_set_bit(dev, op->failed.d, BCH_SB_MEMBERS_MAX) + bch2_open_bucket_write_error(c, &op->open_buckets, dev); + + bch2_open_buckets_put(c, &op->open_buckets); + return; +err: + keys->top = keys->keys; + op->error = ret; + op->flags |= BCH_WRITE_DONE; + goto out; +} + +static inline void __wp_update_state(struct write_point *wp, enum write_point_state state) +{ + if (state != wp->state) { + u64 now = ktime_get_ns(); + + if (wp->last_state_change && + time_after64(now, wp->last_state_change)) + wp->time[wp->state] += now - wp->last_state_change; + wp->state = state; + wp->last_state_change = now; + } +} + +static inline void wp_update_state(struct write_point *wp, bool running) +{ + enum write_point_state state; + + state = running ? WRITE_POINT_running : + !list_empty(&wp->writes) ? WRITE_POINT_waiting_io + : WRITE_POINT_stopped; + + __wp_update_state(wp, state); +} + +static CLOSURE_CALLBACK(bch2_write_index) +{ + closure_type(op, struct bch_write_op, cl); + struct write_point *wp = op->wp; + struct workqueue_struct *wq = index_update_wq(op); + unsigned long flags; + + if ((op->flags & BCH_WRITE_DONE) && + (op->flags & BCH_WRITE_MOVE)) + bch2_bio_free_pages_pool(op->c, &op->wbio.bio); + + spin_lock_irqsave(&wp->writes_lock, flags); + if (wp->state == WRITE_POINT_waiting_io) + __wp_update_state(wp, WRITE_POINT_waiting_work); + list_add_tail(&op->wp_list, &wp->writes); + spin_unlock_irqrestore (&wp->writes_lock, flags); + + queue_work(wq, &wp->index_update_work); +} + +static inline void bch2_write_queue(struct bch_write_op *op, struct write_point *wp) +{ + op->wp = wp; + + if (wp->state == WRITE_POINT_stopped) { + spin_lock_irq(&wp->writes_lock); + __wp_update_state(wp, WRITE_POINT_waiting_io); + spin_unlock_irq(&wp->writes_lock); + } +} + +void bch2_write_point_do_index_updates(struct work_struct *work) +{ + struct write_point *wp = + container_of(work, struct write_point, index_update_work); + struct bch_write_op *op; + + while (1) { + spin_lock_irq(&wp->writes_lock); + op = list_first_entry_or_null(&wp->writes, struct bch_write_op, wp_list); + if (op) + list_del(&op->wp_list); + wp_update_state(wp, op != NULL); + spin_unlock_irq(&wp->writes_lock); + + if (!op) + break; + + op->flags |= BCH_WRITE_IN_WORKER; + + __bch2_write_index(op); + + if (!(op->flags & BCH_WRITE_DONE)) + __bch2_write(op); + else + bch2_write_done(&op->cl); + } +} + +static void bch2_write_endio(struct bio *bio) +{ + struct closure *cl = bio->bi_private; + struct bch_write_op *op = container_of(cl, struct bch_write_op, cl); + struct bch_write_bio *wbio = to_wbio(bio); + struct bch_write_bio *parent = wbio->split ? wbio->parent : NULL; + struct bch_fs *c = wbio->c; + struct bch_dev *ca = bch_dev_bkey_exists(c, wbio->dev); + + if (bch2_dev_inum_io_err_on(bio->bi_status, ca, BCH_MEMBER_ERROR_write, + op->pos.inode, + wbio->inode_offset << 9, + "data write error: %s", + bch2_blk_status_to_str(bio->bi_status))) { + set_bit(wbio->dev, op->failed.d); + op->flags |= BCH_WRITE_IO_ERROR; + } + + if (wbio->nocow) + set_bit(wbio->dev, op->devs_need_flush->d); + + if (wbio->have_ioref) { + bch2_latency_acct(ca, wbio->submit_time, WRITE); + percpu_ref_put(&ca->io_ref); + } + + if (wbio->bounce) + bch2_bio_free_pages_pool(c, bio); + + if (wbio->put_bio) + bio_put(bio); + + if (parent) + bio_endio(&parent->bio); + else + closure_put(cl); +} + +static void init_append_extent(struct bch_write_op *op, + struct write_point *wp, + struct bversion version, + struct bch_extent_crc_unpacked crc) +{ + struct bkey_i_extent *e; + + op->pos.offset += crc.uncompressed_size; + + e = bkey_extent_init(op->insert_keys.top); + e->k.p = op->pos; + e->k.size = crc.uncompressed_size; + e->k.version = version; + + if (crc.csum_type || + crc.compression_type || + crc.nonce) + bch2_extent_crc_append(&e->k_i, crc); + + bch2_alloc_sectors_append_ptrs_inlined(op->c, wp, &e->k_i, crc.compressed_size, + op->flags & BCH_WRITE_CACHED); + + bch2_keylist_push(&op->insert_keys); +} + +static struct bio *bch2_write_bio_alloc(struct bch_fs *c, + struct write_point *wp, + struct bio *src, + bool *page_alloc_failed, + void *buf) +{ + struct bch_write_bio *wbio; + struct bio *bio; + unsigned output_available = + min(wp->sectors_free << 9, src->bi_iter.bi_size); + unsigned pages = DIV_ROUND_UP(output_available + + (buf + ? ((unsigned long) buf & (PAGE_SIZE - 1)) + : 0), PAGE_SIZE); + + pages = min(pages, BIO_MAX_VECS); + + bio = bio_alloc_bioset(NULL, pages, 0, + GFP_NOFS, &c->bio_write); + wbio = wbio_init(bio); + wbio->put_bio = true; + /* copy WRITE_SYNC flag */ + wbio->bio.bi_opf = src->bi_opf; + + if (buf) { + bch2_bio_map(bio, buf, output_available); + return bio; + } + + wbio->bounce = true; + + /* + * We can't use mempool for more than c->sb.encoded_extent_max + * worth of pages, but we'd like to allocate more if we can: + */ + bch2_bio_alloc_pages_pool(c, bio, + min_t(unsigned, output_available, + c->opts.encoded_extent_max)); + + if (bio->bi_iter.bi_size < output_available) + *page_alloc_failed = + bch2_bio_alloc_pages(bio, + output_available - + bio->bi_iter.bi_size, + GFP_NOFS) != 0; + + return bio; +} + +static int bch2_write_rechecksum(struct bch_fs *c, + struct bch_write_op *op, + unsigned new_csum_type) +{ + struct bio *bio = &op->wbio.bio; + struct bch_extent_crc_unpacked new_crc; + int ret; + + /* bch2_rechecksum_bio() can't encrypt or decrypt data: */ + + if (bch2_csum_type_is_encryption(op->crc.csum_type) != + bch2_csum_type_is_encryption(new_csum_type)) + new_csum_type = op->crc.csum_type; + + ret = bch2_rechecksum_bio(c, bio, op->version, op->crc, + NULL, &new_crc, + op->crc.offset, op->crc.live_size, + new_csum_type); + if (ret) + return ret; + + bio_advance(bio, op->crc.offset << 9); + bio->bi_iter.bi_size = op->crc.live_size << 9; + op->crc = new_crc; + return 0; +} + +static int bch2_write_decrypt(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + struct nonce nonce = extent_nonce(op->version, op->crc); + struct bch_csum csum; + int ret; + + if (!bch2_csum_type_is_encryption(op->crc.csum_type)) + return 0; + + /* + * If we need to decrypt data in the write path, we'll no longer be able + * to verify the existing checksum (poly1305 mac, in this case) after + * it's decrypted - this is the last point we'll be able to reverify the + * checksum: + */ + csum = bch2_checksum_bio(c, op->crc.csum_type, nonce, &op->wbio.bio); + if (bch2_crc_cmp(op->crc.csum, csum) && !c->opts.no_data_io) + return -EIO; + + ret = bch2_encrypt_bio(c, op->crc.csum_type, nonce, &op->wbio.bio); + op->crc.csum_type = 0; + op->crc.csum = (struct bch_csum) { 0, 0 }; + return ret; +} + +static enum prep_encoded_ret { + PREP_ENCODED_OK, + PREP_ENCODED_ERR, + PREP_ENCODED_CHECKSUM_ERR, + PREP_ENCODED_DO_WRITE, +} bch2_write_prep_encoded_data(struct bch_write_op *op, struct write_point *wp) +{ + struct bch_fs *c = op->c; + struct bio *bio = &op->wbio.bio; + + if (!(op->flags & BCH_WRITE_DATA_ENCODED)) + return PREP_ENCODED_OK; + + BUG_ON(bio_sectors(bio) != op->crc.compressed_size); + + /* Can we just write the entire extent as is? */ + if (op->crc.uncompressed_size == op->crc.live_size && + op->crc.uncompressed_size <= c->opts.encoded_extent_max >> 9 && + op->crc.compressed_size <= wp->sectors_free && + (op->crc.compression_type == bch2_compression_opt_to_type(op->compression_opt) || + op->incompressible)) { + if (!crc_is_compressed(op->crc) && + op->csum_type != op->crc.csum_type && + bch2_write_rechecksum(c, op, op->csum_type) && + !c->opts.no_data_io) + return PREP_ENCODED_CHECKSUM_ERR; + + return PREP_ENCODED_DO_WRITE; + } + + /* + * If the data is compressed and we couldn't write the entire extent as + * is, we have to decompress it: + */ + if (crc_is_compressed(op->crc)) { + struct bch_csum csum; + + if (bch2_write_decrypt(op)) + return PREP_ENCODED_CHECKSUM_ERR; + + /* Last point we can still verify checksum: */ + csum = bch2_checksum_bio(c, op->crc.csum_type, + extent_nonce(op->version, op->crc), + bio); + if (bch2_crc_cmp(op->crc.csum, csum) && !c->opts.no_data_io) + return PREP_ENCODED_CHECKSUM_ERR; + + if (bch2_bio_uncompress_inplace(c, bio, &op->crc)) + return PREP_ENCODED_ERR; + } + + /* + * No longer have compressed data after this point - data might be + * encrypted: + */ + + /* + * If the data is checksummed and we're only writing a subset, + * rechecksum and adjust bio to point to currently live data: + */ + if ((op->crc.live_size != op->crc.uncompressed_size || + op->crc.csum_type != op->csum_type) && + bch2_write_rechecksum(c, op, op->csum_type) && + !c->opts.no_data_io) + return PREP_ENCODED_CHECKSUM_ERR; + + /* + * If we want to compress the data, it has to be decrypted: + */ + if ((op->compression_opt || + bch2_csum_type_is_encryption(op->crc.csum_type) != + bch2_csum_type_is_encryption(op->csum_type)) && + bch2_write_decrypt(op)) + return PREP_ENCODED_CHECKSUM_ERR; + + return PREP_ENCODED_OK; +} + +static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp, + struct bio **_dst) +{ + struct bch_fs *c = op->c; + struct bio *src = &op->wbio.bio, *dst = src; + struct bvec_iter saved_iter; + void *ec_buf; + unsigned total_output = 0, total_input = 0; + bool bounce = false; + bool page_alloc_failed = false; + int ret, more = 0; + + BUG_ON(!bio_sectors(src)); + + ec_buf = bch2_writepoint_ec_buf(c, wp); + + switch (bch2_write_prep_encoded_data(op, wp)) { + case PREP_ENCODED_OK: + break; + case PREP_ENCODED_ERR: + ret = -EIO; + goto err; + case PREP_ENCODED_CHECKSUM_ERR: + goto csum_err; + case PREP_ENCODED_DO_WRITE: + /* XXX look for bug here */ + if (ec_buf) { + dst = bch2_write_bio_alloc(c, wp, src, + &page_alloc_failed, + ec_buf); + bio_copy_data(dst, src); + bounce = true; + } + init_append_extent(op, wp, op->version, op->crc); + goto do_write; + } + + if (ec_buf || + op->compression_opt || + (op->csum_type && + !(op->flags & BCH_WRITE_PAGES_STABLE)) || + (bch2_csum_type_is_encryption(op->csum_type) && + !(op->flags & BCH_WRITE_PAGES_OWNED))) { + dst = bch2_write_bio_alloc(c, wp, src, + &page_alloc_failed, + ec_buf); + bounce = true; + } + + saved_iter = dst->bi_iter; + + do { + struct bch_extent_crc_unpacked crc = { 0 }; + struct bversion version = op->version; + size_t dst_len = 0, src_len = 0; + + if (page_alloc_failed && + dst->bi_iter.bi_size < (wp->sectors_free << 9) && + dst->bi_iter.bi_size < c->opts.encoded_extent_max) + break; + + BUG_ON(op->compression_opt && + (op->flags & BCH_WRITE_DATA_ENCODED) && + bch2_csum_type_is_encryption(op->crc.csum_type)); + BUG_ON(op->compression_opt && !bounce); + + crc.compression_type = op->incompressible + ? BCH_COMPRESSION_TYPE_incompressible + : op->compression_opt + ? bch2_bio_compress(c, dst, &dst_len, src, &src_len, + op->compression_opt) + : 0; + if (!crc_is_compressed(crc)) { + dst_len = min(dst->bi_iter.bi_size, src->bi_iter.bi_size); + dst_len = min_t(unsigned, dst_len, wp->sectors_free << 9); + + if (op->csum_type) + dst_len = min_t(unsigned, dst_len, + c->opts.encoded_extent_max); + + if (bounce) { + swap(dst->bi_iter.bi_size, dst_len); + bio_copy_data(dst, src); + swap(dst->bi_iter.bi_size, dst_len); + } + + src_len = dst_len; + } + + BUG_ON(!src_len || !dst_len); + + if (bch2_csum_type_is_encryption(op->csum_type)) { + if (bversion_zero(version)) { + version.lo = atomic64_inc_return(&c->key_version); + } else { + crc.nonce = op->nonce; + op->nonce += src_len >> 9; + } + } + + if ((op->flags & BCH_WRITE_DATA_ENCODED) && + !crc_is_compressed(crc) && + bch2_csum_type_is_encryption(op->crc.csum_type) == + bch2_csum_type_is_encryption(op->csum_type)) { + u8 compression_type = crc.compression_type; + u16 nonce = crc.nonce; + /* + * Note: when we're using rechecksum(), we need to be + * checksumming @src because it has all the data our + * existing checksum covers - if we bounced (because we + * were trying to compress), @dst will only have the + * part of the data the new checksum will cover. + * + * But normally we want to be checksumming post bounce, + * because part of the reason for bouncing is so the + * data can't be modified (by userspace) while it's in + * flight. + */ + if (bch2_rechecksum_bio(c, src, version, op->crc, + &crc, &op->crc, + src_len >> 9, + bio_sectors(src) - (src_len >> 9), + op->csum_type)) + goto csum_err; + /* + * rchecksum_bio sets compression_type on crc from op->crc, + * this isn't always correct as sometimes we're changing + * an extent from uncompressed to incompressible. + */ + crc.compression_type = compression_type; + crc.nonce = nonce; + } else { + if ((op->flags & BCH_WRITE_DATA_ENCODED) && + bch2_rechecksum_bio(c, src, version, op->crc, + NULL, &op->crc, + src_len >> 9, + bio_sectors(src) - (src_len >> 9), + op->crc.csum_type)) + goto csum_err; + + crc.compressed_size = dst_len >> 9; + crc.uncompressed_size = src_len >> 9; + crc.live_size = src_len >> 9; + + swap(dst->bi_iter.bi_size, dst_len); + ret = bch2_encrypt_bio(c, op->csum_type, + extent_nonce(version, crc), dst); + if (ret) + goto err; + + crc.csum = bch2_checksum_bio(c, op->csum_type, + extent_nonce(version, crc), dst); + crc.csum_type = op->csum_type; + swap(dst->bi_iter.bi_size, dst_len); + } + + init_append_extent(op, wp, version, crc); + + if (dst != src) + bio_advance(dst, dst_len); + bio_advance(src, src_len); + total_output += dst_len; + total_input += src_len; + } while (dst->bi_iter.bi_size && + src->bi_iter.bi_size && + wp->sectors_free && + !bch2_keylist_realloc(&op->insert_keys, + op->inline_keys, + ARRAY_SIZE(op->inline_keys), + BKEY_EXTENT_U64s_MAX)); + + more = src->bi_iter.bi_size != 0; + + dst->bi_iter = saved_iter; + + if (dst == src && more) { + BUG_ON(total_output != total_input); + + dst = bio_split(src, total_input >> 9, + GFP_NOFS, &c->bio_write); + wbio_init(dst)->put_bio = true; + /* copy WRITE_SYNC flag */ + dst->bi_opf = src->bi_opf; + } + + dst->bi_iter.bi_size = total_output; +do_write: + *_dst = dst; + return more; +csum_err: + bch_err(c, "error verifying existing checksum while rewriting existing data (memory corruption?)"); + ret = -EIO; +err: + if (to_wbio(dst)->bounce) + bch2_bio_free_pages_pool(c, dst); + if (to_wbio(dst)->put_bio) + bio_put(dst); + + return ret; +} + +static bool bch2_extent_is_writeable(struct bch_write_op *op, + struct bkey_s_c k) +{ + struct bch_fs *c = op->c; + struct bkey_s_c_extent e; + struct extent_ptr_decoded p; + const union bch_extent_entry *entry; + unsigned replicas = 0; + + if (k.k->type != KEY_TYPE_extent) + return false; + + e = bkey_s_c_to_extent(k); + extent_for_each_ptr_decode(e, p, entry) { + if (crc_is_encoded(p.crc) || p.has_ec) + return false; + + replicas += bch2_extent_ptr_durability(c, &p); + } + + return replicas >= op->opts.data_replicas; +} + +static inline void bch2_nocow_write_unlock(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + + for_each_keylist_key(&op->insert_keys, k) { + struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(k)); + + bkey_for_each_ptr(ptrs, ptr) + bch2_bucket_nocow_unlock(&c->nocow_locks, + PTR_BUCKET_POS(c, ptr), + BUCKET_NOCOW_LOCK_UPDATE); + } +} + +static int bch2_nocow_write_convert_one_unwritten(struct btree_trans *trans, + struct btree_iter *iter, + struct bkey_i *orig, + struct bkey_s_c k, + u64 new_i_size) +{ + if (!bch2_extents_match(bkey_i_to_s_c(orig), k)) { + /* trace this */ + return 0; + } + + struct bkey_i *new = bch2_bkey_make_mut_noupdate(trans, k); + int ret = PTR_ERR_OR_ZERO(new); + if (ret) + return ret; + + bch2_cut_front(bkey_start_pos(&orig->k), new); + bch2_cut_back(orig->k.p, new); + + struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(new)); + bkey_for_each_ptr(ptrs, ptr) + ptr->unwritten = 0; + + /* + * Note that we're not calling bch2_subvol_get_snapshot() in this path - + * that was done when we kicked off the write, and here it's important + * that we update the extent that we wrote to - even if a snapshot has + * since been created. The write is still outstanding, so we're ok + * w.r.t. snapshot atomicity: + */ + return bch2_extent_update_i_size_sectors(trans, iter, + min(new->k.p.offset << 9, new_i_size), 0) ?: + bch2_trans_update(trans, iter, new, + BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE); +} + +static void bch2_nocow_write_convert_unwritten(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + struct btree_trans *trans = bch2_trans_get(c); + + for_each_keylist_key(&op->insert_keys, orig) { + int ret = for_each_btree_key_upto_commit(trans, iter, BTREE_ID_extents, + bkey_start_pos(&orig->k), orig->k.p, + BTREE_ITER_INTENT, k, + NULL, NULL, BCH_TRANS_COMMIT_no_enospc, ({ + bch2_nocow_write_convert_one_unwritten(trans, &iter, orig, k, op->new_i_size); + })); + + if (ret && !bch2_err_matches(ret, EROFS)) { + struct bkey_i *insert = bch2_keylist_front(&op->insert_keys); + + bch_err_inum_offset_ratelimited(c, + insert->k.p.inode, insert->k.p.offset << 9, + "write error while doing btree update: %s", + bch2_err_str(ret)); + } + + if (ret) { + op->error = ret; + break; + } + } + + bch2_trans_put(trans); +} + +static void __bch2_nocow_write_done(struct bch_write_op *op) +{ + bch2_nocow_write_unlock(op); + + if (unlikely(op->flags & BCH_WRITE_IO_ERROR)) { + op->error = -EIO; + } else if (unlikely(op->flags & BCH_WRITE_CONVERT_UNWRITTEN)) + bch2_nocow_write_convert_unwritten(op); +} + +static CLOSURE_CALLBACK(bch2_nocow_write_done) +{ + closure_type(op, struct bch_write_op, cl); + + __bch2_nocow_write_done(op); + bch2_write_done(cl); +} + +struct bucket_to_lock { + struct bpos b; + unsigned gen; + struct nocow_lock_bucket *l; +}; + +static void bch2_nocow_write(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + struct btree_trans *trans; + struct btree_iter iter; + struct bkey_s_c k; + DARRAY_PREALLOCATED(struct bucket_to_lock, 3) buckets; + u32 snapshot; + struct bucket_to_lock *stale_at; + int ret; + + if (op->flags & BCH_WRITE_MOVE) + return; + + darray_init(&buckets); + trans = bch2_trans_get(c); +retry: + bch2_trans_begin(trans); + + ret = bch2_subvolume_get_snapshot(trans, op->subvol, &snapshot); + if (unlikely(ret)) + goto err; + + bch2_trans_iter_init(trans, &iter, BTREE_ID_extents, + SPOS(op->pos.inode, op->pos.offset, snapshot), + BTREE_ITER_SLOTS); + while (1) { + struct bio *bio = &op->wbio.bio; + + buckets.nr = 0; + + k = bch2_btree_iter_peek_slot(&iter); + ret = bkey_err(k); + if (ret) + break; + + /* fall back to normal cow write path? */ + if (unlikely(k.k->p.snapshot != snapshot || + !bch2_extent_is_writeable(op, k))) + break; + + if (bch2_keylist_realloc(&op->insert_keys, + op->inline_keys, + ARRAY_SIZE(op->inline_keys), + k.k->u64s)) + break; + + /* Get iorefs before dropping btree locks: */ + struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k); + bkey_for_each_ptr(ptrs, ptr) { + struct bpos b = PTR_BUCKET_POS(c, ptr); + struct nocow_lock_bucket *l = + bucket_nocow_lock(&c->nocow_locks, bucket_to_u64(b)); + prefetch(l); + + if (unlikely(!bch2_dev_get_ioref(bch_dev_bkey_exists(c, ptr->dev), WRITE))) + goto err_get_ioref; + + /* XXX allocating memory with btree locks held - rare */ + darray_push_gfp(&buckets, ((struct bucket_to_lock) { + .b = b, .gen = ptr->gen, .l = l, + }), GFP_KERNEL|__GFP_NOFAIL); + + if (ptr->unwritten) + op->flags |= BCH_WRITE_CONVERT_UNWRITTEN; + } + + /* Unlock before taking nocow locks, doing IO: */ + bkey_reassemble(op->insert_keys.top, k); + bch2_trans_unlock(trans); + + bch2_cut_front(op->pos, op->insert_keys.top); + if (op->flags & BCH_WRITE_CONVERT_UNWRITTEN) + bch2_cut_back(POS(op->pos.inode, op->pos.offset + bio_sectors(bio)), op->insert_keys.top); + + darray_for_each(buckets, i) { + struct bch_dev *ca = bch_dev_bkey_exists(c, i->b.inode); + + __bch2_bucket_nocow_lock(&c->nocow_locks, i->l, + bucket_to_u64(i->b), + BUCKET_NOCOW_LOCK_UPDATE); + + rcu_read_lock(); + bool stale = gen_after(*bucket_gen(ca, i->b.offset), i->gen); + rcu_read_unlock(); + + if (unlikely(stale)) { + stale_at = i; + goto err_bucket_stale; + } + } + + bio = &op->wbio.bio; + if (k.k->p.offset < op->pos.offset + bio_sectors(bio)) { + bio = bio_split(bio, k.k->p.offset - op->pos.offset, + GFP_KERNEL, &c->bio_write); + wbio_init(bio)->put_bio = true; + bio->bi_opf = op->wbio.bio.bi_opf; + } else { + op->flags |= BCH_WRITE_DONE; + } + + op->pos.offset += bio_sectors(bio); + op->written += bio_sectors(bio); + + bio->bi_end_io = bch2_write_endio; + bio->bi_private = &op->cl; + bio->bi_opf |= REQ_OP_WRITE; + closure_get(&op->cl); + bch2_submit_wbio_replicas(to_wbio(bio), c, BCH_DATA_user, + op->insert_keys.top, true); + + bch2_keylist_push(&op->insert_keys); + if (op->flags & BCH_WRITE_DONE) + break; + bch2_btree_iter_advance(&iter); + } +out: + bch2_trans_iter_exit(trans, &iter); +err: + if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) + goto retry; + + if (ret) { + bch_err_inum_offset_ratelimited(c, + op->pos.inode, op->pos.offset << 9, + "%s: btree lookup error %s", __func__, bch2_err_str(ret)); + op->error = ret; + op->flags |= BCH_WRITE_DONE; + } + + bch2_trans_put(trans); + darray_exit(&buckets); + + /* fallback to cow write path? */ + if (!(op->flags & BCH_WRITE_DONE)) { + closure_sync(&op->cl); + __bch2_nocow_write_done(op); + op->insert_keys.top = op->insert_keys.keys; + } else if (op->flags & BCH_WRITE_SYNC) { + closure_sync(&op->cl); + bch2_nocow_write_done(&op->cl.work); + } else { + /* + * XXX + * needs to run out of process context because ei_quota_lock is + * a mutex + */ + continue_at(&op->cl, bch2_nocow_write_done, index_update_wq(op)); + } + return; +err_get_ioref: + darray_for_each(buckets, i) + percpu_ref_put(&bch_dev_bkey_exists(c, i->b.inode)->io_ref); + + /* Fall back to COW path: */ + goto out; +err_bucket_stale: + darray_for_each(buckets, i) { + bch2_bucket_nocow_unlock(&c->nocow_locks, i->b, BUCKET_NOCOW_LOCK_UPDATE); + if (i == stale_at) + break; + } + + /* We can retry this: */ + ret = -BCH_ERR_transaction_restart; + goto err_get_ioref; +} + +static void __bch2_write(struct bch_write_op *op) +{ + struct bch_fs *c = op->c; + struct write_point *wp = NULL; + struct bio *bio = NULL; + unsigned nofs_flags; + int ret; + + nofs_flags = memalloc_nofs_save(); + + if (unlikely(op->opts.nocow && c->opts.nocow_enabled)) { + bch2_nocow_write(op); + if (op->flags & BCH_WRITE_DONE) + goto out_nofs_restore; + } +again: + memset(&op->failed, 0, sizeof(op->failed)); + + do { + struct bkey_i *key_to_write; + unsigned key_to_write_offset = op->insert_keys.top_p - + op->insert_keys.keys_p; + + /* +1 for possible cache device: */ + if (op->open_buckets.nr + op->nr_replicas + 1 > + ARRAY_SIZE(op->open_buckets.v)) + break; + + if (bch2_keylist_realloc(&op->insert_keys, + op->inline_keys, + ARRAY_SIZE(op->inline_keys), + BKEY_EXTENT_U64s_MAX)) + break; + + /* + * The copygc thread is now global, which means it's no longer + * freeing up space on specific disks, which means that + * allocations for specific disks may hang arbitrarily long: + */ + ret = bch2_trans_do(c, NULL, NULL, 0, + bch2_alloc_sectors_start_trans(trans, + op->target, + op->opts.erasure_code && !(op->flags & BCH_WRITE_CACHED), + op->write_point, + &op->devs_have, + op->nr_replicas, + op->nr_replicas_required, + op->watermark, + op->flags, + (op->flags & (BCH_WRITE_ALLOC_NOWAIT| + BCH_WRITE_ONLY_SPECIFIED_DEVS)) + ? NULL : &op->cl, &wp)); + if (unlikely(ret)) { + if (bch2_err_matches(ret, BCH_ERR_operation_blocked)) + break; + + goto err; + } + + EBUG_ON(!wp); + + bch2_open_bucket_get(c, wp, &op->open_buckets); + ret = bch2_write_extent(op, wp, &bio); + + bch2_alloc_sectors_done_inlined(c, wp); +err: + if (ret <= 0) { + op->flags |= BCH_WRITE_DONE; + + if (ret < 0) { + bch_err_inum_offset_ratelimited(c, + op->pos.inode, + op->pos.offset << 9, + "%s(): error: %s", __func__, bch2_err_str(ret)); + op->error = ret; + break; + } + } + + bio->bi_end_io = bch2_write_endio; + bio->bi_private = &op->cl; + bio->bi_opf |= REQ_OP_WRITE; + + closure_get(bio->bi_private); + + key_to_write = (void *) (op->insert_keys.keys_p + + key_to_write_offset); + + bch2_submit_wbio_replicas(to_wbio(bio), c, BCH_DATA_user, + key_to_write, false); + } while (ret); + + /* + * Sync or no? + * + * If we're running asynchronously, wne may still want to block + * synchronously here if we weren't able to submit all of the IO at + * once, as that signals backpressure to the caller. + */ + if ((op->flags & BCH_WRITE_SYNC) || + (!(op->flags & BCH_WRITE_DONE) && + !(op->flags & BCH_WRITE_IN_WORKER))) { + closure_sync(&op->cl); + __bch2_write_index(op); + + if (!(op->flags & BCH_WRITE_DONE)) + goto again; + bch2_write_done(&op->cl); + } else { + bch2_write_queue(op, wp); + continue_at(&op->cl, bch2_write_index, NULL); + } +out_nofs_restore: + memalloc_nofs_restore(nofs_flags); +} + +static void bch2_write_data_inline(struct bch_write_op *op, unsigned data_len) +{ + struct bio *bio = &op->wbio.bio; + struct bvec_iter iter; + struct bkey_i_inline_data *id; + unsigned sectors; + int ret; + + op->flags |= BCH_WRITE_WROTE_DATA_INLINE; + op->flags |= BCH_WRITE_DONE; + + bch2_check_set_feature(op->c, BCH_FEATURE_inline_data); + + ret = bch2_keylist_realloc(&op->insert_keys, op->inline_keys, + ARRAY_SIZE(op->inline_keys), + BKEY_U64s + DIV_ROUND_UP(data_len, 8)); + if (ret) { + op->error = ret; + goto err; + } + + sectors = bio_sectors(bio); + op->pos.offset += sectors; + + id = bkey_inline_data_init(op->insert_keys.top); + id->k.p = op->pos; + id->k.version = op->version; + id->k.size = sectors; + + iter = bio->bi_iter; + iter.bi_size = data_len; + memcpy_from_bio(id->v.data, bio, iter); + + while (data_len & 7) + id->v.data[data_len++] = '\0'; + set_bkey_val_bytes(&id->k, data_len); + bch2_keylist_push(&op->insert_keys); + + __bch2_write_index(op); +err: + bch2_write_done(&op->cl); +} + +/** + * bch2_write() - handle a write to a cache device or flash only volume + * @cl: &bch_write_op->cl + * + * This is the starting point for any data to end up in a cache device; it could + * be from a normal write, or a writeback write, or a write to a flash only + * volume - it's also used by the moving garbage collector to compact data in + * mostly empty buckets. + * + * It first writes the data to the cache, creating a list of keys to be inserted + * (if the data won't fit in a single open bucket, there will be multiple keys); + * after the data is written it calls bch_journal, and after the keys have been + * added to the next journal write they're inserted into the btree. + * + * If op->discard is true, instead of inserting the data it invalidates the + * region of the cache represented by op->bio and op->inode. + */ +CLOSURE_CALLBACK(bch2_write) +{ + closure_type(op, struct bch_write_op, cl); + struct bio *bio = &op->wbio.bio; + struct bch_fs *c = op->c; + unsigned data_len; + + EBUG_ON(op->cl.parent); + BUG_ON(!op->nr_replicas); + BUG_ON(!op->write_point.v); + BUG_ON(bkey_eq(op->pos, POS_MAX)); + + op->start_time = local_clock(); + bch2_keylist_init(&op->insert_keys, op->inline_keys); + wbio_init(bio)->put_bio = false; + + if (bio->bi_iter.bi_size & (c->opts.block_size - 1)) { + bch_err_inum_offset_ratelimited(c, + op->pos.inode, + op->pos.offset << 9, + "misaligned write"); + op->error = -EIO; + goto err; + } + + if (c->opts.nochanges) { + op->error = -BCH_ERR_erofs_no_writes; + goto err; + } + + if (!(op->flags & BCH_WRITE_MOVE) && + !bch2_write_ref_tryget(c, BCH_WRITE_REF_write)) { + op->error = -BCH_ERR_erofs_no_writes; + goto err; + } + + this_cpu_add(c->counters[BCH_COUNTER_io_write], bio_sectors(bio)); + bch2_increment_clock(c, bio_sectors(bio), WRITE); + + data_len = min_t(u64, bio->bi_iter.bi_size, + op->new_i_size - (op->pos.offset << 9)); + + if (c->opts.inline_data && + data_len <= min(block_bytes(c) / 2, 1024U)) { + bch2_write_data_inline(op, data_len); + return; + } + + __bch2_write(op); + return; +err: + bch2_disk_reservation_put(c, &op->res); + + closure_debug_destroy(&op->cl); + if (op->end_io) + op->end_io(op); +} + +static const char * const bch2_write_flags[] = { +#define x(f) #f, + BCH_WRITE_FLAGS() +#undef x + NULL +}; + +void bch2_write_op_to_text(struct printbuf *out, struct bch_write_op *op) +{ + prt_str(out, "pos: "); + bch2_bpos_to_text(out, op->pos); + prt_newline(out); + printbuf_indent_add(out, 2); + + prt_str(out, "started: "); + bch2_pr_time_units(out, local_clock() - op->start_time); + prt_newline(out); + + prt_str(out, "flags: "); + prt_bitflags(out, bch2_write_flags, op->flags); + prt_newline(out); + + prt_printf(out, "ref: %u", closure_nr_remaining(&op->cl)); + prt_newline(out); + + printbuf_indent_sub(out, 2); +} + +void bch2_fs_io_write_exit(struct bch_fs *c) +{ + mempool_exit(&c->bio_bounce_pages); + bioset_exit(&c->bio_write); +} + +int bch2_fs_io_write_init(struct bch_fs *c) +{ + if (bioset_init(&c->bio_write, 1, offsetof(struct bch_write_bio, bio), + BIOSET_NEED_BVECS)) + return -BCH_ERR_ENOMEM_bio_write_init; + + if (mempool_init_page_pool(&c->bio_bounce_pages, + max_t(unsigned, + c->opts.btree_node_size, + c->opts.encoded_extent_max) / + PAGE_SIZE, 0)) + return -BCH_ERR_ENOMEM_bio_bounce_pages_init; + + return 0; +} -- cgit v1.2.3