Re: [PATCH v2 13/34] bcache: port block device access to files

[Jan Kara <jack@suse.cz>]

On Tue 23-01-24 14:26:30, Christian Brauner wrote:
> Signed-off-by: Christian Brauner <brauner@kernel.org>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  drivers/md/bcache/bcache.h |  4 +--
>  drivers/md/bcache/super.c  | 74 +++++++++++++++++++++++-----------------------
>  2 files changed, 39 insertions(+), 39 deletions(-)
> 
> diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
> index 6ae2329052c9..4e6afa89921f 100644
> --- a/drivers/md/bcache/bcache.h
> +++ b/drivers/md/bcache/bcache.h
> @@ -300,7 +300,7 @@ struct cached_dev {
>  	struct list_head	list;
>  	struct bcache_device	disk;
>  	struct block_device	*bdev;
> -	struct bdev_handle	*bdev_handle;
> +	struct file		*bdev_file;
>  
>  	struct cache_sb		sb;
>  	struct cache_sb_disk	*sb_disk;
> @@ -423,7 +423,7 @@ struct cache {
>  
>  	struct kobject		kobj;
>  	struct block_device	*bdev;
> -	struct bdev_handle	*bdev_handle;
> +	struct file		*bdev_file;
>  
>  	struct task_struct	*alloc_thread;
>  
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index dc3f50f69714..d00b3abab133 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -1369,8 +1369,8 @@ static CLOSURE_CALLBACK(cached_dev_free)
>  	if (dc->sb_disk)
>  		put_page(virt_to_page(dc->sb_disk));
>  
> -	if (dc->bdev_handle)
> -		bdev_release(dc->bdev_handle);
> +	if (dc->bdev_file)
> +		fput(dc->bdev_file);
>  
>  	wake_up(&unregister_wait);
>  
> @@ -1445,7 +1445,7 @@ 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 bdev_handle *bdev_handle,
> +				 struct file *bdev_file,
>  				 struct cached_dev *dc)
>  {
>  	const char *err = "cannot allocate memory";
> @@ -1453,8 +1453,8 @@ 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_handle = bdev_handle;
> -	dc->bdev = bdev_handle->bdev;
> +	dc->bdev_file = bdev_file;
> +	dc->bdev = file_bdev(bdev_file);
>  	dc->sb_disk = sb_disk;
>  
>  	if (cached_dev_init(dc, sb->block_size << 9))
> @@ -2218,8 +2218,8 @@ void bch_cache_release(struct kobject *kobj)
>  	if (ca->sb_disk)
>  		put_page(virt_to_page(ca->sb_disk));
>  
> -	if (ca->bdev_handle)
> -		bdev_release(ca->bdev_handle);
> +	if (ca->bdev_file)
> +		fput(ca->bdev_file);
>  
>  	kfree(ca);
>  	module_put(THIS_MODULE);
> @@ -2339,18 +2339,18 @@ static int cache_alloc(struct cache *ca)
>  }
>  
>  static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> -				struct bdev_handle *bdev_handle,
> +				struct file *bdev_file,
>  				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_handle = bdev_handle;
> -	ca->bdev = bdev_handle->bdev;
> +	ca->bdev_file = bdev_file;
> +	ca->bdev = file_bdev(bdev_file);
>  	ca->sb_disk = sb_disk;
>  
> -	if (bdev_max_discard_sectors((bdev_handle->bdev)))
> +	if (bdev_max_discard_sectors(file_bdev(bdev_file)))
>  		ca->discard = CACHE_DISCARD(&ca->sb);
>  
>  	ret = cache_alloc(ca);
> @@ -2361,20 +2361,20 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
>  			err = "cache_alloc(): cache device is too small";
>  		else
>  			err = "cache_alloc(): unknown error";
> -		pr_notice("error %pg: %s\n", bdev_handle->bdev, err);
> +		pr_notice("error %pg: %s\n", file_bdev(bdev_file), err);
>  		/*
>  		 * 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 bdev_release() to bdev in bch_cache_release(). So
> -		 * we explicitly call bdev_release() here.
> +		 * call fput() to bdev in bch_cache_release(). So
> +		 * we explicitly call fput() on the block device here.
>  		 */
> -		bdev_release(bdev_handle);
> +		fput(bdev_file);
>  		return ret;
>  	}
>  
> -	if (kobject_add(&ca->kobj, bdev_kobj(bdev_handle->bdev), "bcache")) {
> +	if (kobject_add(&ca->kobj, bdev_kobj(file_bdev(bdev_file)), "bcache")) {
>  		pr_notice("error %pg: error calling kobject_add\n",
> -			  bdev_handle->bdev);
> +			  file_bdev(bdev_file));
>  		ret = -ENOMEM;
>  		goto out;
>  	}
> @@ -2388,7 +2388,7 @@ 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_handle->bdev);
> +	pr_info("registered cache device %pg\n", file_bdev(ca->bdev_file));
>  
>  out:
>  	kobject_put(&ca->kobj);
> @@ -2446,7 +2446,7 @@ struct async_reg_args {
>  	char *path;
>  	struct cache_sb *sb;
>  	struct cache_sb_disk *sb_disk;
> -	struct bdev_handle *bdev_handle;
> +	struct file *bdev_file;
>  	void *holder;
>  };
>  
> @@ -2457,7 +2457,7 @@ 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_handle,
> +	if (register_bdev(args->sb, args->sb_disk, args->bdev_file,
>  			  args->holder) < 0)
>  		fail = true;
>  	mutex_unlock(&bch_register_lock);
> @@ -2478,7 +2478,7 @@ 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_handle,
> +	if (register_cache(args->sb, args->sb_disk, args->bdev_file,
>  			   args->holder))
>  		fail = true;
>  
> @@ -2516,7 +2516,7 @@ 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 bdev_handle *bdev_handle, *bdev_handle2;
> +	struct file *bdev_file, *bdev_file2;
>  	void *holder = NULL;
>  	ssize_t ret;
>  	bool async_registration = false;
> @@ -2549,15 +2549,15 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  
>  	ret = -EINVAL;
>  	err = "failed to open device";
> -	bdev_handle = bdev_open_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
> -	if (IS_ERR(bdev_handle))
> +	bdev_file = bdev_file_open_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
> +	if (IS_ERR(bdev_file))
>  		goto out_free_sb;
>  
>  	err = "failed to set blocksize";
> -	if (set_blocksize(bdev_handle->bdev, 4096))
> +	if (set_blocksize(file_bdev(bdev_file), 4096))
>  		goto out_blkdev_put;
>  
> -	err = read_super(sb, bdev_handle->bdev, &sb_disk);
> +	err = read_super(sb, file_bdev(bdev_file), &sb_disk);
>  	if (err)
>  		goto out_blkdev_put;
>  
> @@ -2569,13 +2569,13 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  	}
>  
>  	/* Now reopen in exclusive mode with proper holder */
> -	bdev_handle2 = bdev_open_by_dev(bdev_handle->bdev->bd_dev,
> +	bdev_file2 = bdev_file_open_by_dev(file_bdev(bdev_file)->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;
> +	fput(bdev_file);
> +	bdev_file = bdev_file2;
> +	if (IS_ERR(bdev_file)) {
> +		ret = PTR_ERR(bdev_file);
> +		bdev_file = NULL;
>  		if (ret == -EBUSY) {
>  			dev_t dev;
>  
> @@ -2610,7 +2610,7 @@ 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_handle	= bdev_handle;
> +		args->bdev_file	= bdev_file;
>  		args->holder	= holder;
>  		register_device_async(args);
>  		/* No wait and returns to user space */
> @@ -2619,14 +2619,14 @@ 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_handle, holder);
> +		ret = register_bdev(sb, sb_disk, bdev_file, 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_handle, holder);
> +		ret = register_cache(sb, sb_disk, bdev_file, holder);
>  		if (ret)
>  			goto out_free_sb;
>  	}
> @@ -2642,8 +2642,8 @@ 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_handle)
> -		bdev_release(bdev_handle);
> +	if (bdev_file)
> +		fput(bdev_file);
>  out_free_sb:
>  	kfree(sb);
>  out_free_path:
> 
> -- 
> 2.43.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR