bcache: Convert to bdev_open_by_path()

Convert bcache to use bdev_open_by_path() and pass the handle around.

CC: linux-bcache@vger.kernel.org
CC: Coly Li <colyli@suse.de>
CC: Kent Overstreet <kent.overstreet@gmail.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230927093442.25915-9-jack@suse.cz
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 5a79bb3c272f1ba9adfd786699f983ae4505c6a1..2aa3f2c1f7192db013a435ce9d6ec768de34c839 100644 (file)
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -299,6 +299,7 @@ struct cached_dev {
        struct list_head        list;
        struct bcache_device    disk;
        struct block_device     *bdev;
+       struct bdev_handle      *bdev_handle;
 
        struct cache_sb         sb;
        struct cache_sb_disk    *sb_disk;
@@ -421,6 +422,7 @@ struct cache {
 
        struct kobject          kobj;
        struct block_device     *bdev;
+       struct bdev_handle      *bdev_handle;
 
        struct task_struct      *alloc_thread;
 

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 0ae2b3676293074a1621226ceee76f0cac6b5d63..c11ac86be72b05335e33dbb8d99e6d170f28af18 100644 (file)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1368,8 +1368,8 @@ static void cached_dev_free(struct closure *cl)
        if (dc->sb_disk)
                put_page(virt_to_page(dc->sb_disk));
 
-       if (!IS_ERR_OR_NULL(dc->bdev))
-               blkdev_put(dc->bdev, dc);
+       if (dc->bdev_handle)
+               bdev_release(dc->bdev_handle);
 
        wake_up(&unregister_wait);
 
@@ -1444,7 +1444,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
 /* Cached device - bcache superblock */
 
 static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
-                                struct block_device *bdev,
+                                struct bdev_handle *bdev_handle,
                                 struct cached_dev *dc)
 {
        const char *err = "cannot allocate memory";
@@ -1452,14 +1452,15 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
        int ret = -ENOMEM;
 
        memcpy(&dc->sb, sb, sizeof(struct cache_sb));
-       dc->bdev = bdev;
+       dc->bdev_handle = bdev_handle;
+       dc->bdev = bdev_handle->bdev;
        dc->sb_disk = sb_disk;
 
        if (cached_dev_init(dc, sb->block_size << 9))
                goto err;
 
        err = "error creating kobject";
-       if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache"))
+       if (kobject_add(&dc->disk.kobj, bdev_kobj(dc->bdev), "bcache"))
                goto err;
        if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
                goto err;
@@ -2216,8 +2217,8 @@ void bch_cache_release(struct kobject *kobj)
        if (ca->sb_disk)
                put_page(virt_to_page(ca->sb_disk));
 
-       if (!IS_ERR_OR_NULL(ca->bdev))
-               blkdev_put(ca->bdev, ca);
+       if (ca->bdev_handle)
+               bdev_release(ca->bdev_handle);
 
        kfree(ca);
        module_put(THIS_MODULE);
@@ -2337,16 +2338,18 @@ static int cache_alloc(struct cache *ca)
 }
 
 static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
-                               struct block_device *bdev, struct cache *ca)
+                               struct bdev_handle *bdev_handle,
+                               struct cache *ca)
 {
        const char *err = NULL; /* must be set for any error case */
        int ret = 0;
 
        memcpy(&ca->sb, sb, sizeof(struct cache_sb));
-       ca->bdev = bdev;
+       ca->bdev_handle = bdev_handle;
+       ca->bdev = bdev_handle->bdev;
        ca->sb_disk = sb_disk;
 
-       if (bdev_max_discard_sectors((bdev)))
+       if (bdev_max_discard_sectors((bdev_handle->bdev)))
                ca->discard = CACHE_DISCARD(&ca->sb);
 
        ret = cache_alloc(ca);
@@ -2354,10 +2357,10 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
                /*
                 * If we failed here, it means ca->kobj is not initialized yet,
                 * kobject_put() won't be called and there is no chance to
-                * call blkdev_put() to bdev in bch_cache_release(). So we
-                * explicitly call blkdev_put() here.
+                * call bdev_release() to bdev in bch_cache_release(). So
+                * we explicitly call bdev_release() here.
                 */
-               blkdev_put(bdev, ca);
+               bdev_release(bdev_handle);
                if (ret == -ENOMEM)
                        err = "cache_alloc(): -ENOMEM";
                else if (ret == -EPERM)
@@ -2367,7 +2370,7 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
                goto err;
        }
 
-       if (kobject_add(&ca->kobj, bdev_kobj(bdev), "bcache")) {
+       if (kobject_add(&ca->kobj, bdev_kobj(bdev_handle->bdev), "bcache")) {
                err = "error calling kobject_add";
                ret = -ENOMEM;
                goto out;
@@ -2382,14 +2385,14 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
                goto out;
        }
 
-       pr_info("registered cache device %pg\n", ca->bdev);
+       pr_info("registered cache device %pg\n", ca->bdev_handle->bdev);
 
 out:
        kobject_put(&ca->kobj);
 
 err:
        if (err)
-               pr_notice("error %pg: %s\n", ca->bdev, err);
+               pr_notice("error %pg: %s\n", ca->bdev_handle->bdev, err);
 
        return ret;
 }
@@ -2445,7 +2448,7 @@ struct async_reg_args {
        char *path;
        struct cache_sb *sb;
        struct cache_sb_disk *sb_disk;
-       struct block_device *bdev;
+       struct bdev_handle *bdev_handle;
        void *holder;
 };
 
@@ -2456,8 +2459,8 @@ static void register_bdev_worker(struct work_struct *work)
                container_of(work, struct async_reg_args, reg_work.work);
 
        mutex_lock(&bch_register_lock);
-       if (register_bdev(args->sb, args->sb_disk, args->bdev, args->holder)
-           < 0)
+       if (register_bdev(args->sb, args->sb_disk, args->bdev_handle,
+                         args->holder) < 0)
                fail = true;
        mutex_unlock(&bch_register_lock);
 
@@ -2477,7 +2480,8 @@ static void register_cache_worker(struct work_struct *work)
                container_of(work, struct async_reg_args, reg_work.work);
 
        /* blkdev_put() will be called in bch_cache_release() */
-       if (register_cache(args->sb, args->sb_disk, args->bdev, args->holder))
+       if (register_cache(args->sb, args->sb_disk, args->bdev_handle,
+                          args->holder))
                fail = true;
 
        if (fail)
@@ -2514,7 +2518,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
        char *path = NULL;
        struct cache_sb *sb;
        struct cache_sb_disk *sb_disk;
-       struct block_device *bdev, *bdev2;
+       struct bdev_handle *bdev_handle, *bdev_handle2;
        void *holder = NULL;
        ssize_t ret;
        bool async_registration = false;
@@ -2547,15 +2551,15 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 
        ret = -EINVAL;
        err = "failed to open device";
-       bdev = blkdev_get_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
-       if (IS_ERR(bdev))
+       bdev_handle = bdev_open_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
+       if (IS_ERR(bdev_handle))
                goto out_free_sb;
 
        err = "failed to set blocksize";
-       if (set_blocksize(bdev, 4096))
+       if (set_blocksize(bdev_handle->bdev, 4096))
                goto out_blkdev_put;
 
-       err = read_super(sb, bdev, &sb_disk);
+       err = read_super(sb, bdev_handle->bdev, &sb_disk);
        if (err)
                goto out_blkdev_put;
 
@@ -2567,13 +2571,13 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
        }
 
        /* Now reopen in exclusive mode with proper holder */
-       bdev2 = blkdev_get_by_dev(bdev->bd_dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
-                                 holder, NULL);
-       blkdev_put(bdev, NULL);
-       bdev = bdev2;
-       if (IS_ERR(bdev)) {
-               ret = PTR_ERR(bdev);
-               bdev = NULL;
+       bdev_handle2 = bdev_open_by_dev(bdev_handle->bdev->bd_dev,
+                       BLK_OPEN_READ | BLK_OPEN_WRITE, holder, NULL);
+       bdev_release(bdev_handle);
+       bdev_handle = bdev_handle2;
+       if (IS_ERR(bdev_handle)) {
+               ret = PTR_ERR(bdev_handle);
+               bdev_handle = NULL;
                if (ret == -EBUSY) {
                        dev_t dev;
 
@@ -2608,7 +2612,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
                args->path      = path;
                args->sb        = sb;
                args->sb_disk   = sb_disk;
-               args->bdev      = bdev;
+               args->bdev_handle       = bdev_handle;
                args->holder    = holder;
                register_device_async(args);
                /* No wait and returns to user space */
@@ -2617,14 +2621,14 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 
        if (SB_IS_BDEV(sb)) {
                mutex_lock(&bch_register_lock);
-               ret = register_bdev(sb, sb_disk, bdev, holder);
+               ret = register_bdev(sb, sb_disk, bdev_handle, holder);
                mutex_unlock(&bch_register_lock);
                /* blkdev_put() will be called in cached_dev_free() */
                if (ret < 0)
                        goto out_free_sb;
        } else {
                /* blkdev_put() will be called in bch_cache_release() */
-               ret = register_cache(sb, sb_disk, bdev, holder);
+               ret = register_cache(sb, sb_disk, bdev_handle, holder);
                if (ret)
                        goto out_free_sb;
        }
@@ -2640,8 +2644,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 out_put_sb_page:
        put_page(virt_to_page(sb_disk));
 out_blkdev_put:
-       if (bdev)
-               blkdev_put(bdev, holder);
+       if (bdev_handle)
+               bdev_release(bdev_handle);
 out_free_sb:
        kfree(sb);
 out_free_path: