bcachefs: bch2_data_update_init() cleanup

Factor out some helpers - this function has gotten much too big.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/data_update.c b/fs/bcachefs/data_update.c
index 1ca628e93e87f163f2bdf6cdd69e737383877900..5f49f4953b19d0a0c717923d3334914951720077 100644 (file)
--- a/fs/bcachefs/data_update.c
+++ b/fs/bcachefs/data_update.c
@@ -20,6 +20,76 @@
 #include "subvolume.h"
 #include "trace.h"
 
+static void bkey_put_dev_refs(struct bch_fs *c, struct bkey_s_c k)
+{
+       struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+
+       bkey_for_each_ptr(ptrs, ptr)
+               bch2_dev_put(bch2_dev_have_ref(c, ptr->dev));
+}
+
+static bool bkey_get_dev_refs(struct bch_fs *c, struct bkey_s_c k)
+{
+       struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+
+       bkey_for_each_ptr(ptrs, ptr) {
+               if (!bch2_dev_tryget(c, ptr->dev)) {
+                       bkey_for_each_ptr(ptrs, ptr2) {
+                               if (ptr2 == ptr)
+                                       break;
+                               bch2_dev_put(bch2_dev_have_ref(c, ptr2->dev));
+                       }
+                       return false;
+               }
+       }
+       return true;
+}
+
+static void bkey_nocow_unlock(struct bch_fs *c, struct bkey_s_c k)
+{
+       struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+
+       bkey_for_each_ptr(ptrs, ptr) {
+               struct bch_dev *ca = bch2_dev_have_ref(c, ptr->dev);
+               struct bpos bucket = PTR_BUCKET_POS(ca, ptr);
+
+               bch2_bucket_nocow_unlock(&c->nocow_locks, bucket, 0);
+       }
+}
+
+static bool bkey_nocow_lock(struct bch_fs *c, struct moving_context *ctxt, struct bkey_s_c k)
+{
+       struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
+
+       bkey_for_each_ptr(ptrs, ptr) {
+               struct bch_dev *ca = bch2_dev_have_ref(c, ptr->dev);
+               struct bpos bucket = PTR_BUCKET_POS(ca, ptr);
+
+               if (ctxt) {
+                       bool locked;
+
+                       move_ctxt_wait_event(ctxt,
+                               (locked = bch2_bucket_nocow_trylock(&c->nocow_locks, bucket, 0)) ||
+                               list_empty(&ctxt->ios));
+
+                       if (!locked)
+                               bch2_bucket_nocow_lock(&c->nocow_locks, bucket, 0);
+               } else {
+                       if (!bch2_bucket_nocow_trylock(&c->nocow_locks, bucket, 0)) {
+                               bkey_for_each_ptr(ptrs, ptr2) {
+                                       if (ptr2 == ptr)
+                                               break;
+
+                                       bucket = PTR_BUCKET_POS(ca, ptr2);
+                                       bch2_bucket_nocow_unlock(&c->nocow_locks, bucket, 0);
+                               }
+                               return false;
+                       }
+               }
+       }
+       return true;
+}
+
 static void trace_move_extent_finish2(struct bch_fs *c, struct bkey_s_c k)
 {
        if (trace_move_extent_finish_enabled()) {
@@ -355,17 +425,11 @@ void bch2_data_update_read_done(struct data_update *m,
 void bch2_data_update_exit(struct data_update *update)
 {
        struct bch_fs *c = update->op.c;
-       struct bkey_ptrs_c ptrs =
-               bch2_bkey_ptrs_c(bkey_i_to_s_c(update->k.k));
-
-       bkey_for_each_ptr(ptrs, ptr) {
-               struct bch_dev *ca = bch2_dev_have_ref(c, ptr->dev);
-               if (c->opts.nocow_enabled)
-                       bch2_bucket_nocow_unlock(&c->nocow_locks,
-                                                PTR_BUCKET_POS(ca, ptr), 0);
-               bch2_dev_put(ca);
-       }
+       struct bkey_s_c k = bkey_i_to_s_c(update->k.k);
 
+       if (c->opts.nocow_enabled)
+               bkey_nocow_unlock(c, k);
+       bkey_put_dev_refs(c, k);
        bch2_bkey_buf_exit(&update->k, c);
        bch2_disk_reservation_put(c, &update->op.res);
        bch2_bio_free_pages_pool(c, &update->op.wbio.bio);
@@ -546,7 +610,6 @@ int bch2_data_update_init(struct btree_trans *trans,
        const union bch_extent_entry *entry;
        struct extent_ptr_decoded p;
        unsigned i, reserve_sectors = k.k->size * data_opts.extra_replicas;
-       unsigned ptrs_locked = 0;
        int ret = 0;
 
        /*
@@ -557,6 +620,15 @@ int bch2_data_update_init(struct btree_trans *trans,
        if (unlikely(k.k->p.snapshot && !bch2_snapshot_equiv(c, k.k->p.snapshot)))
                return -BCH_ERR_data_update_done;
 
+       if (!bkey_get_dev_refs(c, k))
+               return -BCH_ERR_data_update_done;
+
+       if (c->opts.nocow_enabled &&
+           !bkey_nocow_lock(c, ctxt, k)) {
+               bkey_put_dev_refs(c, k);
+               return -BCH_ERR_nocow_lock_blocked;
+       }
+
        bch2_bkey_buf_init(&m->k);
        bch2_bkey_buf_reassemble(&m->k, c, k);
        m->btree_id     = btree_id;
@@ -578,40 +650,24 @@ int bch2_data_update_init(struct btree_trans *trans,
        m->op.compression_opt   = background_compression(io_opts);
        m->op.watermark         = m->data_opts.btree_insert_flags & BCH_WATERMARK_MASK;
 
-       bkey_for_each_ptr(ptrs, ptr) {
-               if (!bch2_dev_tryget(c, ptr->dev)) {
-                       bkey_for_each_ptr(ptrs, ptr2) {
-                               if (ptr2 == ptr)
-                                       break;
-                               bch2_dev_put(bch2_dev_have_ref(c, ptr2->dev));
-                       }
-                       return -BCH_ERR_data_update_done;
-               }
-       }
-
        unsigned durability_have = 0, durability_removing = 0;
 
        i = 0;
        bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
-               struct bch_dev *ca = bch2_dev_have_ref(c, p.ptr.dev);
-               struct bpos bucket = PTR_BUCKET_POS(ca, &p.ptr);
-               bool locked;
-
-               rcu_read_lock();
-               if (((1U << i) & m->data_opts.rewrite_ptrs)) {
-                       BUG_ON(p.ptr.cached);
-
-                       if (crc_is_compressed(p.crc))
-                               reserve_sectors += k.k->size;
-
-                       m->op.nr_replicas += bch2_extent_ptr_desired_durability(c, &p);
-                       durability_removing += bch2_extent_ptr_desired_durability(c, &p);
-               } else if (!p.ptr.cached &&
-                          !((1U << i) & m->data_opts.kill_ptrs)) {
-                       bch2_dev_list_add_dev(&m->op.devs_have, p.ptr.dev);
-                       durability_have += bch2_extent_ptr_durability(c, &p);
+               if (!p.ptr.cached) {
+                       rcu_read_lock();
+                       if (BIT(i) & m->data_opts.rewrite_ptrs) {
+                               if (crc_is_compressed(p.crc))
+                                       reserve_sectors += k.k->size;
+
+                               m->op.nr_replicas += bch2_extent_ptr_desired_durability(c, &p);
+                               durability_removing += bch2_extent_ptr_desired_durability(c, &p);
+                       } else if (!(BIT(i) & m->data_opts.kill_ptrs)) {
+                               bch2_dev_list_add_dev(&m->op.devs_have, p.ptr.dev);
+                               durability_have += bch2_extent_ptr_durability(c, &p);
+                       }
+                       rcu_read_unlock();
                }
-               rcu_read_unlock();
 
                /*
                 * op->csum_type is normally initialized from the fs/file's
@@ -626,24 +682,6 @@ int bch2_data_update_init(struct btree_trans *trans,
                if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
                        m->op.incompressible = true;
 
-               if (c->opts.nocow_enabled) {
-                       if (ctxt) {
-                               move_ctxt_wait_event(ctxt,
-                                               (locked = bch2_bucket_nocow_trylock(&c->nocow_locks,
-                                                                         bucket, 0)) ||
-                                               list_empty(&ctxt->ios));
-
-                               if (!locked)
-                                       bch2_bucket_nocow_lock(&c->nocow_locks, bucket, 0);
-                       } else {
-                               if (!bch2_bucket_nocow_trylock(&c->nocow_locks, bucket, 0)) {
-                                       ret = -BCH_ERR_nocow_lock_blocked;
-                                       goto err;
-                               }
-                       }
-                       ptrs_locked |= (1U << i);
-               }
-
                i++;
        }
 
@@ -664,7 +702,7 @@ int bch2_data_update_init(struct btree_trans *trans,
                /* if iter == NULL, it's just a promote */
                if (iter)
                        ret = bch2_extent_drop_ptrs(trans, iter, k, m->data_opts);
-               goto done;
+               goto out;
        }
 
        m->op.nr_replicas = min(durability_removing, durability_required) +
@@ -684,8 +722,7 @@ int bch2_data_update_init(struct btree_trans *trans,
                bch2_data_update_to_text(&buf, m);
                WARN(1, "trying to move an extent, but nr_replicas=0\n%s", buf.buf);
                printbuf_exit(&buf);
-               ret = -BCH_ERR_data_update_done;
-               goto done;
+               goto out;
        }
 
        m->op.nr_replicas_required = m->op.nr_replicas;
@@ -696,30 +733,16 @@ int bch2_data_update_init(struct btree_trans *trans,
                                ? 0
                                : BCH_DISK_RESERVATION_NOFAIL);
                if (ret)
-                       goto err;
+                       goto out;
        }
 
        if (bkey_extent_is_unwritten(k)) {
                bch2_update_unwritten_extent(trans, m);
-               goto done;
+               goto out;
        }
 
        return 0;
-err:
-       i = 0;
-       bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
-               struct bch_dev *ca = bch2_dev_have_ref(c, p.ptr.dev);
-               struct bpos bucket = PTR_BUCKET_POS(ca, &p.ptr);
-               if ((1U << i) & ptrs_locked)
-                       bch2_bucket_nocow_unlock(&c->nocow_locks, bucket, 0);
-               bch2_dev_put(ca);
-               i++;
-       }
-
-       bch2_bkey_buf_exit(&m->k, c);
-       bch2_bio_free_pages_pool(c, &m->op.wbio.bio);
-       return ret;
-done:
+out:
        bch2_data_update_exit(m);
        return ret ?: -BCH_ERR_data_update_done;
 }