md/raid1: change r1conf->r1bio_pool to a pointer type

In raid1_reshape(), newpool is a stack variable.
mempool_init() initializes newpool->wait with the stack address.
After assigning newpool to conf->r1bio_pool, the wait queue
need to be reinitialized, which is not ideal.

Change raid1_conf->r1bio_pool to a pointer type and
replace mempool_init() with mempool_create_kmalloc_pool() to
avoid referencing a stack-based wait queue.

Signed-off-by: Wang Jinchao <wangjinchao600@gmail.com>
Link: https://lore.kernel.org/linux-raid/20250707012711.376844-2-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 6cee738a645ff22c5542f77765c77e294cc3ac70..589223fef20a9f7b3b819734af9c180f29b6d69e 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -255,7 +255,7 @@ static void free_r1bio(struct r1bio *r1_bio)
        struct r1conf *conf = r1_bio->mddev->private;
 
        put_all_bios(conf, r1_bio);
-       mempool_free(r1_bio, &conf->r1bio_pool);
+       mempool_free(r1_bio, conf->r1bio_pool);
 }
 
 static void put_buf(struct r1bio *r1_bio)
@@ -1305,9 +1305,8 @@ alloc_r1bio(struct mddev *mddev, struct bio *bio)
        struct r1conf *conf = mddev->private;
        struct r1bio *r1_bio;
 
-       r1_bio = mempool_alloc(&conf->r1bio_pool, GFP_NOIO);
-       /* Ensure no bio records IO_BLOCKED */
-       memset(r1_bio->bios, 0, conf->raid_disks * sizeof(r1_bio->bios[0]));
+       r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
+       memset(r1_bio, 0, offsetof(struct r1bio, bios[conf->raid_disks * 2]));
        init_r1bio(r1_bio, mddev, bio);
        return r1_bio;
 }
@@ -3085,6 +3084,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
        int i;
        struct raid1_info *disk;
        struct md_rdev *rdev;
+       size_t r1bio_size;
        int err = -ENOMEM;
 
        conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL);
@@ -3125,9 +3125,10 @@ static struct r1conf *setup_conf(struct mddev *mddev)
        if (!conf->poolinfo)
                goto abort;
        conf->poolinfo->raid_disks = mddev->raid_disks * 2;
-       err = mempool_init(&conf->r1bio_pool, NR_RAID_BIOS, r1bio_pool_alloc,
-                          rbio_pool_free, conf->poolinfo);
-       if (err)
+
+       r1bio_size = offsetof(struct r1bio, bios[mddev->raid_disks * 2]);
+       conf->r1bio_pool = mempool_create_kmalloc_pool(NR_RAID_BIOS, r1bio_size);
+       if (!conf->r1bio_pool)
                goto abort;
 
        err = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
@@ -3198,7 +3199,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
 
  abort:
        if (conf) {
-               mempool_exit(&conf->r1bio_pool);
+               mempool_destroy(conf->r1bio_pool);
                kfree(conf->mirrors);
                safe_put_page(conf->tmppage);
                kfree(conf->poolinfo);
@@ -3311,7 +3312,7 @@ static void raid1_free(struct mddev *mddev, void *priv)
 {
        struct r1conf *conf = priv;
 
-       mempool_exit(&conf->r1bio_pool);
+       mempool_destroy(conf->r1bio_pool);
        kfree(conf->mirrors);
        safe_put_page(conf->tmppage);
        kfree(conf->poolinfo);
@@ -3367,17 +3368,14 @@ static int raid1_reshape(struct mddev *mddev)
         * At the same time, we "pack" the devices so that all the missing
         * devices have the higher raid_disk numbers.
         */
-       mempool_t newpool, oldpool;
+       mempool_t *newpool, *oldpool;
        struct pool_info *newpoolinfo;
+       size_t new_r1bio_size;
        struct raid1_info *newmirrors;
        struct r1conf *conf = mddev->private;
        int cnt, raid_disks;
        unsigned long flags;
        int d, d2;
-       int ret;
-
-       memset(&newpool, 0, sizeof(newpool));
-       memset(&oldpool, 0, sizeof(oldpool));
 
        /* Cannot change chunk_size, layout, or level */
        if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
@@ -3409,18 +3407,18 @@ static int raid1_reshape(struct mddev *mddev)
        newpoolinfo->mddev = mddev;
        newpoolinfo->raid_disks = raid_disks * 2;
 
-       ret = mempool_init(&newpool, NR_RAID_BIOS, r1bio_pool_alloc,
-                          rbio_pool_free, newpoolinfo);
-       if (ret) {
+       new_r1bio_size = offsetof(struct r1bio, bios[raid_disks * 2]);
+       newpool = mempool_create_kmalloc_pool(NR_RAID_BIOS, new_r1bio_size);
+       if (!newpool) {
                kfree(newpoolinfo);
-               return ret;
+               return -ENOMEM;
        }
        newmirrors = kzalloc(array3_size(sizeof(struct raid1_info),
                                         raid_disks, 2),
                             GFP_KERNEL);
        if (!newmirrors) {
                kfree(newpoolinfo);
-               mempool_exit(&newpool);
+               mempool_destroy(newpool);
                return -ENOMEM;
        }
 
@@ -3429,7 +3427,6 @@ static int raid1_reshape(struct mddev *mddev)
        /* ok, everything is stopped */
        oldpool = conf->r1bio_pool;
        conf->r1bio_pool = newpool;
-       init_waitqueue_head(&conf->r1bio_pool.wait);
 
        for (d = d2 = 0; d < conf->raid_disks; d++) {
                struct md_rdev *rdev = conf->mirrors[d].rdev;
@@ -3461,7 +3458,7 @@ static int raid1_reshape(struct mddev *mddev)
        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
        md_wakeup_thread(mddev->thread);
 
-       mempool_exit(&oldpool);
+       mempool_destroy(oldpool);
        return 0;
 }
 

diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
index 33f318fcc268d80cb5edb0639ccb36c9e58e599e..652c347b1a70137e6b6cd66dc68d32f4b2a83ec8 100644 (file)
--- a/drivers/md/raid1.h
+++ b/drivers/md/raid1.h
@@ -118,7 +118,7 @@ struct r1conf {
         * mempools - it changes when the array grows or shrinks
         */
        struct pool_info        *poolinfo;
-       mempool_t               r1bio_pool;
+       mempool_t               *r1bio_pool;
        mempool_t               r1buf_pool;
 
        struct bio_set          bio_split;