bcachefs: for_each_member_device_rcu() now declares loop iter

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

fs/bcachefs/alloc_background.c

@@ -891,7 +891,6 @@ static struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos
 static bool next_bucket(struct bch_fs *c, struct bpos *bucket)
 {
 	struct bch_dev *ca;
-	unsigned iter;
 
 	if (bch2_dev_bucket_exists(c, *bucket))
 		return true;
@@ -909,8 +908,7 @@ static bool next_bucket(struct bch_fs *c, struct bpos *bucket)
 	}
 
 	rcu_read_lock();
-	iter = bucket->inode;
-	ca = __bch2_next_dev(c, &iter, NULL);
+	ca = __bch2_next_dev_idx(c, bucket->inode, NULL);
 	if (ca)
 		*bucket = POS(ca->dev_idx, ca->mi.first_bucket);
 	rcu_read_unlock();

fs/bcachefs/alloc_foreground.c

@@ -69,11 +69,8 @@ const char * const bch2_watermarks[] = {
 
 void bch2_reset_alloc_cursors(struct bch_fs *c)
 {
-	struct bch_dev *ca;
-	unsigned i;
-
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i, NULL)
+	for_each_member_device_rcu(c, ca, NULL)
 		ca->alloc_cursor = 0;
 	rcu_read_unlock();
 }

fs/bcachefs/buckets.c

@@ -154,8 +154,7 @@ struct bch_fs_usage_online *bch2_fs_usage_read(struct bch_fs *c)
 
 void bch2_fs_usage_acc_to_base(struct bch_fs *c, unsigned idx)
 {
-	struct bch_dev *ca;
-	unsigned i, u64s = fs_usage_u64s(c);
+	unsigned u64s = fs_usage_u64s(c);
 
 	BUG_ON(idx >= ARRAY_SIZE(c->usage));
 
@@ -167,7 +166,7 @@ void bch2_fs_usage_acc_to_base(struct bch_fs *c, unsigned idx)
 	percpu_memset(c->usage[idx], 0, u64s * sizeof(u64));
 
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i, NULL) {
+	for_each_member_device_rcu(c, ca, NULL) {
 		u64s = dev_usage_u64s();
 
 		acc_u64s_percpu((u64 *) ca->usage_base,

fs/bcachefs/disk_groups.c

@@ -89,19 +89,14 @@ static int bch2_sb_disk_groups_validate(struct bch_sb *sb,
 
 void bch2_disk_groups_to_text(struct printbuf *out, struct bch_fs *c)
 {
-	struct bch_disk_groups_cpu *g;
-	struct bch_dev *ca;
-	int i;
-	unsigned iter;
-
 	out->atomic++;
 	rcu_read_lock();
 
-	g = rcu_dereference(c->disk_groups);
+	struct bch_disk_groups_cpu *g = rcu_dereference(c->disk_groups);
 	if (!g)
 		goto out;
 
-	for (i = 0; i < g->nr; i++) {
+	for (unsigned i = 0; i < g->nr; i++) {
 		if (i)
 			prt_printf(out, " ");
 
@@ -111,7 +106,7 @@ void bch2_disk_groups_to_text(struct printbuf *out, struct bch_fs *c)
 		}
 
 		prt_printf(out, "[parent %d devs", g->entries[i].parent);
-		for_each_member_device_rcu(ca, c, iter, &g->entries[i].devs)
+		for_each_member_device_rcu(c, ca, &g->entries[i].devs)
 			prt_printf(out, " %s", ca->name);
 		prt_printf(out, "]");
 	}

fs/bcachefs/ec.c

@@ -1243,18 +1243,17 @@ static int unsigned_cmp(const void *_l, const void *_r)
 static unsigned pick_blocksize(struct bch_fs *c,
 			       struct bch_devs_mask *devs)
 {
-	struct bch_dev *ca;
-	unsigned i, nr = 0, sizes[BCH_SB_MEMBERS_MAX];
+	unsigned nr = 0, sizes[BCH_SB_MEMBERS_MAX];
 	struct {
 		unsigned nr, size;
 	} cur = { 0, 0 }, best = { 0, 0 };
 
-	for_each_member_device_rcu(ca, c, i, devs)
+	for_each_member_device_rcu(c, ca, devs)
 		sizes[nr++] = ca->mi.bucket_size;
 
 	sort(sizes, nr, sizeof(unsigned), unsigned_cmp, NULL);
 
-	for (i = 0; i < nr; i++) {
+	for (unsigned i = 0; i < nr; i++) {
 		if (sizes[i] != cur.size) {
 			if (cur.nr > best.nr)
 				best = cur;
@@ -1337,8 +1336,6 @@ ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
 			 enum bch_watermark watermark)
 {
 	struct ec_stripe_head *h;
-	struct bch_dev *ca;
-	unsigned i;
 
 	h = kzalloc(sizeof(*h), GFP_KERNEL);
 	if (!h)
@@ -1355,13 +1352,13 @@ ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
 	rcu_read_lock();
 	h->devs = target_rw_devs(c, BCH_DATA_user, target);
 
-	for_each_member_device_rcu(ca, c, i, &h->devs)
+	for_each_member_device_rcu(c, ca, &h->devs)
 		if (!ca->mi.durability)
-			__clear_bit(i, h->devs.d);
+			__clear_bit(ca->dev_idx, h->devs.d);
 
 	h->blocksize = pick_blocksize(c, &h->devs);
 
-	for_each_member_device_rcu(ca, c, i, &h->devs)
+	for_each_member_device_rcu(c, ca, &h->devs)
 		if (ca->mi.bucket_size == h->blocksize)
 			h->nr_active_devs++;
 

fs/bcachefs/journal.c

@@ -1294,11 +1294,8 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
 {
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
 	union journal_res_state s;
-	struct bch_dev *ca;
 	unsigned long now = jiffies;
 	u64 nr_writes = j->nr_flush_writes + j->nr_noflush_writes;
-	u64 seq;
-	unsigned i;
 
 	if (!out->nr_tabstops)
 		printbuf_tabstop_push(out, 24);
@@ -1343,10 +1340,10 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
 
 	prt_newline(out);
 
-	for (seq = journal_cur_seq(j);
+	for (u64 seq = journal_cur_seq(j);
 	     seq >= journal_last_unwritten_seq(j);
 	     --seq) {
-		i = seq & JOURNAL_BUF_MASK;
+		unsigned i = seq & JOURNAL_BUF_MASK;
 
 		prt_printf(out, "unwritten entry:");
 		prt_tab(out);
@@ -1390,8 +1387,7 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
 	       j->space[journal_space_total].next_entry,
 	       j->space[journal_space_total].total);
 
-	for_each_member_device_rcu(ca, c, i,
-				   &c->rw_devs[BCH_DATA_journal]) {
+	for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) {
 		struct journal_device *ja = &ca->journal;
 
 		if (!test_bit(ca->dev_idx, c->rw_devs[BCH_DATA_journal].d))
@@ -1400,7 +1396,7 @@ void __bch2_journal_debug_to_text(struct printbuf *out, struct journal *j)
 		if (!ja->nr)
 			continue;
 
-		prt_printf(out, "dev %u:\n",		i);
+		prt_printf(out, "dev %u:\n",		ca->dev_idx);
 		prt_printf(out, "\tnr\t\t%u\n",		ja->nr);
 		prt_printf(out, "\tbucket size\t%u\n",	ca->mi.bucket_size);
 		prt_printf(out, "\tavailable\t%u:%u\n",	bch2_journal_dev_buckets_available(j, ja, journal_space_discarded), ja->sectors_free);

fs/bcachefs/journal_reclaim.c

@@ -136,15 +136,13 @@ static struct journal_space __journal_space_available(struct journal *j, unsigne
 			    enum journal_space_from from)
 {
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
-	struct bch_dev *ca;
-	unsigned i, pos, nr_devs = 0;
+	unsigned pos, nr_devs = 0;
 	struct journal_space space, dev_space[BCH_SB_MEMBERS_MAX];
 
 	BUG_ON(nr_devs_want > ARRAY_SIZE(dev_space));
 
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i,
-				   &c->rw_devs[BCH_DATA_journal]) {
+	for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) {
 		if (!ca->journal.nr)
 			continue;
 
@@ -173,19 +171,17 @@ static struct journal_space __journal_space_available(struct journal *j, unsigne
 void bch2_journal_space_available(struct journal *j)
 {
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
-	struct bch_dev *ca;
 	unsigned clean, clean_ondisk, total;
 	unsigned max_entry_size	 = min(j->buf[0].buf_size >> 9,
 				       j->buf[1].buf_size >> 9);
-	unsigned i, nr_online = 0, nr_devs_want;
+	unsigned nr_online = 0, nr_devs_want;
 	bool can_discard = false;
 	int ret = 0;
 
 	lockdep_assert_held(&j->lock);
 
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i,
-				   &c->rw_devs[BCH_DATA_journal]) {
+	for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) {
 		struct journal_device *ja = &ca->journal;
 
 		if (!ja->nr)
@@ -216,7 +212,7 @@ void bch2_journal_space_available(struct journal *j)
 
 	nr_devs_want = min_t(unsigned, nr_online, c->opts.metadata_replicas);
 
-	for (i = 0; i < journal_space_nr; i++)
+	for (unsigned i = 0; i < journal_space_nr; i++)
 		j->space[i] = __journal_space_available(j, nr_devs_want, i);
 
 	clean_ondisk	= j->space[journal_space_clean_ondisk].total;

fs/bcachefs/sb-members.c

@@ -358,14 +358,12 @@ const struct bch_sb_field_ops bch_sb_field_ops_members_v2 = {
 void bch2_sb_members_from_cpu(struct bch_fs *c)
 {
 	struct bch_sb_field_members_v2 *mi = bch2_sb_field_get(c->disk_sb.sb, members_v2);
-	struct bch_dev *ca;
-	unsigned i, e;
 
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i, NULL) {
-		struct bch_member *m = __bch2_members_v2_get_mut(mi, i);
+	for_each_member_device_rcu(c, ca, NULL) {
+		struct bch_member *m = __bch2_members_v2_get_mut(mi, ca->dev_idx);
 
-		for (e = 0; e < BCH_MEMBER_ERROR_NR; e++)
+		for (unsigned e = 0; e < BCH_MEMBER_ERROR_NR; e++)
 			m->errors[e] = cpu_to_le64(atomic64_read(&ca->errors[e]));
 	}
 	rcu_read_unlock();

fs/bcachefs/sb-members.h

@@ -79,33 +79,38 @@ static inline struct bch_devs_list bch2_dev_list_single(unsigned dev)
 	return (struct bch_devs_list) { .nr = 1, .data[0] = dev };
 }
 
-static inline struct bch_dev *__bch2_next_dev(struct bch_fs *c, unsigned *iter,
-					      const struct bch_devs_mask *mask)
+static inline struct bch_dev *__bch2_next_dev_idx(struct bch_fs *c, unsigned idx,
+						  const struct bch_devs_mask *mask)
 {
 	struct bch_dev *ca = NULL;
 
-	while ((*iter = mask
-		? find_next_bit(mask->d, c->sb.nr_devices, *iter)
-		: *iter) < c->sb.nr_devices &&
-	       !(ca = rcu_dereference_check(c->devs[*iter],
+	while ((idx = mask
+		? find_next_bit(mask->d, c->sb.nr_devices, idx)
+		: idx) < c->sb.nr_devices &&
+	       !(ca = rcu_dereference_check(c->devs[idx],
 					    lockdep_is_held(&c->state_lock))))
-		(*iter)++;
+		idx++;
 
 	return ca;
 }
 
-#define for_each_member_device_rcu(ca, c, iter, mask)			\
-	for ((iter) = 0; ((ca) = __bch2_next_dev((c), &(iter), mask)); (iter)++)
+static inline struct bch_dev *__bch2_next_dev(struct bch_fs *c, struct bch_dev *ca,
+					      const struct bch_devs_mask *mask)
+{
+	return __bch2_next_dev_idx(c, ca ? ca->dev_idx + 1 : 0, mask);
+}
+
+#define for_each_member_device_rcu(_c, _ca, _mask)			\
+	for (struct bch_dev *_ca = NULL;				\
+	     (_ca = __bch2_next_dev((_c), _ca, (_mask)));)
 
 static inline struct bch_dev *bch2_get_next_dev(struct bch_fs *c, struct bch_dev *ca)
 {
-	unsigned idx = ca ? ca->dev_idx + 1 : 0;
-
 	if (ca)
 		percpu_ref_put(&ca->ref);
 
 	rcu_read_lock();
-	if ((ca = __bch2_next_dev(c, &idx, NULL)))
+	if ((ca = __bch2_next_dev(c, ca, NULL)))
 		percpu_ref_get(&ca->ref);
 	rcu_read_unlock();
 
@@ -126,16 +131,14 @@ static inline struct bch_dev *bch2_get_next_online_dev(struct bch_fs *c,
 						       struct bch_dev *ca,
 						       unsigned state_mask)
 {
-	unsigned idx = ca ? ca->dev_idx + 1 : 0;
-
 	if (ca)
 		percpu_ref_put(&ca->io_ref);
 
 	rcu_read_lock();
-	while ((ca = __bch2_next_dev(c, &idx, NULL)) &&
+	while ((ca = __bch2_next_dev(c, ca, NULL)) &&
 	       (!((1 << ca->mi.state) & state_mask) ||
 		!percpu_ref_tryget(&ca->io_ref)))
-		idx++;
+		;
 	rcu_read_unlock();
 
 	return ca;

fs/bcachefs/super.c

@@ -167,14 +167,12 @@ static void __bch2_dev_read_only(struct bch_fs *, struct bch_dev *);
 struct bch_fs *bch2_dev_to_fs(dev_t dev)
 {
 	struct bch_fs *c;
-	struct bch_dev *ca;
-	unsigned i;
 
 	mutex_lock(&bch_fs_list_lock);
 	rcu_read_lock();
 
 	list_for_each_entry(c, &bch_fs_list, list)
-		for_each_member_device_rcu(ca, c, i, NULL)
+		for_each_member_device_rcu(c, ca, NULL)
 			if (ca->disk_sb.bdev && ca->disk_sb.bdev->bd_dev == dev) {
 				closure_get(&c->cl);
 				goto found;
@@ -215,14 +213,13 @@ struct bch_fs *bch2_uuid_to_fs(__uuid_t uuid)
 
 static void bch2_dev_usage_journal_reserve(struct bch_fs *c)
 {
-	struct bch_dev *ca;
-	unsigned i, nr = 0, u64s =
+	unsigned nr = 0, u64s =
 		((sizeof(struct jset_entry_dev_usage) +
 		  sizeof(struct jset_entry_dev_usage_type) * BCH_DATA_NR)) /
 		sizeof(u64);
 
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i, NULL)
+	for_each_member_device_rcu(c, ca, NULL)
 		nr++;
 	rcu_read_unlock();
 
@@ -1906,18 +1903,14 @@ int bch2_dev_resize(struct bch_fs *c, struct bch_dev *ca, u64 nbuckets)
 /* return with ref on ca->ref: */
 struct bch_dev *bch2_dev_lookup(struct bch_fs *c, const char *name)
 {
-	struct bch_dev *ca;
-	unsigned i;
-
 	rcu_read_lock();
-	for_each_member_device_rcu(ca, c, i, NULL)
-		if (!strcmp(name, ca->name))
-			goto found;
-	ca = ERR_PTR(-BCH_ERR_ENOENT_dev_not_found);
-found:
+	for_each_member_device_rcu(c, ca, NULL)
+		if (!strcmp(name, ca->name)) {
+			rcu_read_unlock();
+			return ca;
+		}
 	rcu_read_unlock();
-
-	return ca;
+	return ERR_PTR(-BCH_ERR_ENOENT_dev_not_found);
 }
 
 /* Filesystem open: */