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-rw-r--r--fs/bcachefs/io_write.c1675
1 files changed, 1675 insertions, 0 deletions
diff --git a/fs/bcachefs/io_write.c b/fs/bcachefs/io_write.c
new file mode 100644
index 0000000000..8c8cb1541a
--- /dev/null
+++ b/fs/bcachefs/io_write.c
@@ -0,0 +1,1675 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
+ * 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 <linux/blkdev.h>
+#include <linux/prefetch.h>
+#include <linux/random.h>
+#include <linux/sched/mm.h>
+
+#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,
+ BTREE_INSERT_NOCHECK_RW|
+ BTREE_INSERT_NOFAIL);
+ 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));
+ const struct bch_extent_ptr *ptr;
+ struct bch_write_bio *n;
+ struct bch_dev *ca;
+
+ BUG_ON(c->opts.nochanges);
+
+ bkey_for_each_ptr(ptrs, ptr) {
+ BUG_ON(ptr->dev >= BCH_SB_MEMBERS_MAX ||
+ !c->devs[ptr->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;
+ const struct bch_extent_ptr *ptr;
+ struct bkey_i *k;
+
+ 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)
+{
+ struct bkey_i *new;
+ struct bkey_ptrs ptrs;
+ struct bch_extent_ptr *ptr;
+ int ret;
+
+ if (!bch2_extents_match(bkey_i_to_s_c(orig), k)) {
+ /* trace this */
+ return 0;
+ }
+
+ new = bch2_bkey_make_mut_noupdate(trans, k);
+ 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);
+
+ 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);
+ struct btree_iter iter;
+ struct bkey_i *orig;
+ struct bkey_s_c k;
+ int ret;
+
+ for_each_keylist_key(&op->insert_keys, orig) {
+ 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, BTREE_INSERT_NOFAIL, ({
+ 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;
+ struct bkey_ptrs_c ptrs;
+ const struct bch_extent_ptr *ptr;
+ DARRAY_PREALLOCATED(struct bucket_to_lock, 3) buckets;
+ struct bucket_to_lock *i;
+ 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: */
+ 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) {
+ 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;
+}