Unverified Commit 3789fb87 authored by Christian Brauner's avatar Christian Brauner
Browse files

bcache: port block device access to files 

Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-13-adbd023e19cc@kernel.org


Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent be914f8f

drivers/md/bcache/bcache.h

+2 −2
Original line number Diff line number Diff line
@@ -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;

drivers/md/bcache/super.c

+37 −37
Original line number Diff line number Diff line
@@ -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: