bcache: Warn when a device is already registered. (a9dd53ad) · Commits · 戴 / test

drivers/md/bcache/super.c

+37 −2

Original line number	Diff line number	Diff line
		@@ -1786,6 +1786,36 @@ static ssize_t register_bcache(struct kobject , struct kobj_attribute ,
		kobj_attribute_write(register, register_bcache);
		kobj_attribute_write(register_quiet, register_bcache);

		static bool bch_is_open_backing(struct block_device *bdev) {
		struct cache_set c, tc;
		struct cached_dev dc, t;

		list_for_each_entry_safe(c, tc, &bch_cache_sets, list)
		list_for_each_entry_safe(dc, t, &c->cached_devs, list)
		if (dc->bdev == bdev)
		return true;
		list_for_each_entry_safe(dc, t, &uncached_devices, list)
		if (dc->bdev == bdev)
		return true;
		return false;
		}

		static bool bch_is_open_cache(struct block_device *bdev) {
		struct cache_set c, tc;
		struct cache *ca;
		unsigned i;

		list_for_each_entry_safe(c, tc, &bch_cache_sets, list)
		for_each_cache(ca, c, i)
		if (ca->bdev == bdev)
		return true;
		return false;
		}

		static bool bch_is_open(struct block_device *bdev) {
		return bch_is_open_cache(bdev) \|\| bch_is_open_backing(bdev);
		}

		static ssize_t register_bcache(struct kobject k, struct kobj_attribute attr,
		const char *buffer, size_t size)
		{
		@@ -1810,8 +1840,13 @@ static ssize_t register_bcache(struct kobject k, struct kobj_attribute attr,
		FMODE_READ\|FMODE_WRITE\|FMODE_EXCL,
		sb);
		if (IS_ERR(bdev)) {
		if (bdev == ERR_PTR(-EBUSY))
		if (bdev == ERR_PTR(-EBUSY)) {
		bdev = lookup_bdev(strim(path));
		if (!IS_ERR(bdev) && bch_is_open(bdev))
		err = "device already registered";
		else
		err = "device busy";
		}
		goto err;
		}