[PATCH md-6.15 1/7] md: merge common code into find_pers()

Yu Kuai
2025-02-15T09:25:59Z

- pers_lock() are held and released from caller
- try_module_get() is called from caller
- error message from caller

Merge above code into find_pers(), and rename it to get_pers(), also
add a wrapper to module_put() as put_pers().

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
---
drivers/md/md.c | 68 +++++++++++++++++++++++++++----------------------
1 file changed, 38 insertions(+), 30 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 30b3dbbce2d2..37f3a89eba94 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -888,16 +888,37 @@ struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev)
}
EXPORT_SYMBOL_GPL(md_find_rdev_rcu);

-static struct md_personality *find_pers(int level, char *clevel)
+static struct md_personality *get_pers(int level, char *clevel)
{
+ struct md_personality *ret = NULL;
struct md_personality *pers;
+
+ spin_lock(&pers_lock);
list_for_each_entry(pers, &pers_list, list) {
- if (level != LEVEL_NONE && pers->level == level)
- return pers;
- if (strcmp(pers->name, clevel)==0)
- return pers;
+ if ((level != LEVEL_NONE && pers->level == level) ||
+ !strcmp(pers->name, clevel)) {
+ if (try_module_get(pers->owner))
+ ret = pers;
+ break;
+ }
}
- return NULL;
+ spin_unlock(&pers_lock);
+
+ if (!ret) {
+ if (level != LEVEL_NONE)
+ pr_warn("md: personality for level %d is not loaded!\n",
+ level);
+ else
+ pr_warn("md: personality for level %s is not loaded!\n",
+ clevel);
+ }
+
+ return ret;
+}
+
+static void put_pers(struct md_personality *pers)
+{
+ module_put(pers->owner);
}

/* return the offset of the super block in 512byte sectors */
@@ -3931,24 +3952,20 @@ level_store(struct mddev *mddev, const char *buf, size_t len)

if (request_module("md-%s", clevel) != 0)
request_module("md-level-%s", clevel);
- spin_lock(&pers_lock);
- pers = find_pers(level, clevel);
- if (!pers || !try_module_get(pers->owner)) {
- spin_unlock(&pers_lock);
- pr_warn("md: personality %s not loaded\n", clevel);
+ pers = get_pers(level, clevel);
+ if (!pers) {
rv = -EINVAL;
goto out_unlock;
}
- spin_unlock(&pers_lock);

if (pers == mddev->pers) {
/* Nothing to do! */
- module_put(pers->owner);
+ put_pers(pers);
rv = len;
goto out_unlock;
}
if (!pers->takeover) {
- module_put(pers->owner);
+ put_pers(pers);
pr_warn("md: %s: %s does not support personality takeover\n",
mdname(mddev), clevel);
rv = -EINVAL;
@@ -3969,7 +3986,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len)
mddev->raid_disks -= mddev->delta_disks;
mddev->delta_disks = 0;
mddev->reshape_backwards = 0;
- module_put(pers->owner);
+ put_pers(pers);
pr_warn("md: %s: %s would not accept array\n",
mdname(mddev), clevel);
rv = PTR_ERR(priv);
@@ -4026,7 +4043,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len)
mddev->to_remove = &md_redundancy_group;
}

- module_put(oldpers->owner);
+ put_pers(oldpers);

rdev_for_each(rdev, mddev) {
if (rdev->raid_disk < 0)
@@ -6096,20 +6113,11 @@ int md_run(struct mddev *mddev)
goto exit_sync_set;
}

- spin_lock(&pers_lock);
- pers = find_pers(mddev->level, mddev->clevel);
- if (!pers || !try_module_get(pers->owner)) {
- spin_unlock(&pers_lock);
- if (mddev->level != LEVEL_NONE)
- pr_warn("md: personality for level %d is not loaded!\n",
- mddev->level);
- else
- pr_warn("md: personality for level %s is not loaded!\n",
- mddev->clevel);
+ pers = get_pers(mddev->level, mddev->clevel);
+ if (!pers) {
err = -EINVAL;
goto abort;
}
- spin_unlock(&pers_lock);
if (mddev->level != pers->level) {
mddev->level = pers->level;
mddev->new_level = pers->level;
@@ -6119,7 +6127,7 @@ int md_run(struct mddev *mddev)
if (mddev->reshape_position != MaxSector &&
pers->start_reshape == NULL) {
/* This personality cannot handle reshaping... */
- module_put(pers->owner);
+ put_pers(pers);
err = -EINVAL;
goto abort;
}
@@ -6246,7 +6254,7 @@ int md_run(struct mddev *mddev)
if (mddev->private)
pers->free(mddev, mddev->private);
mddev->private = NULL;
- module_put(pers->owner);
+ put_pers(pers);
mddev->bitmap_ops->destroy(mddev);
abort:
bioset_exit(&mddev->io_clone_set);
@@ -6467,7 +6475,7 @@ static void __md_stop(struct mddev *mddev)
mddev->private = NULL;
if (pers->sync_request && mddev->to_remove == NULL)
mddev->to_remove = &md_redundancy_group;
- module_put(pers->owner);
+ put_pers(pers);
clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

bioset_exit(&mddev->bio_set);
--
2.39.2