Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 53d49819 authored by Joe Thornber's avatar Joe Thornber Committed by Mike Snitzer
Browse files

dm cache metadata: check the metadata version when reading the superblock 



Need to check the version to verify on-disk metadata is supported.

Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 2ee57d58

drivers/md/dm-cache-metadata.c

+21 −3
Original line number Diff line number Diff line
@@ -20,7 +20,13 @@ 


#define CACHE_SUPERBLOCK_MAGIC 06142003

#define CACHE_SUPERBLOCK_LOCATION 0

#define CACHE_VERSION 1



/*

 * defines a range of metadata versions that this module can handle.

 */

#define MIN_CACHE_VERSION 1

#define MAX_CACHE_VERSION 1



#define CACHE_METADATA_CACHE_SIZE 64



/*
@@ -134,6 +140,18 @@ static void sb_prepare_for_write(struct dm_block_validator *v, 
						      SUPERBLOCK_CSUM_XOR));

}



static int check_metadata_version(struct cache_disk_superblock *disk_super)

{

	uint32_t metadata_version = le32_to_cpu(disk_super->version);

	if (metadata_version < MIN_CACHE_VERSION || metadata_version > MAX_CACHE_VERSION) {

		DMERR("Cache metadata version %u found, but only versions between %u and %u supported.",

		      metadata_version, MIN_CACHE_VERSION, MAX_CACHE_VERSION);

		return -EINVAL;

	}



	return 0;

}



static int sb_check(struct dm_block_validator *v,

		    struct dm_block *b,

		    size_t sb_block_size)
@@ -164,7 +182,7 @@ static int sb_check(struct dm_block_validator *v, 
		return -EILSEQ;

	}



	return 0;

	return check_metadata_version(disk_super);

}



static struct dm_block_validator sb_validator = {
@@ -270,7 +288,7 @@ static int __write_initial_superblock(struct dm_cache_metadata *cmd) 
	disk_super->flags = 0;

	memset(disk_super->uuid, 0, sizeof(disk_super->uuid));

	disk_super->magic = cpu_to_le64(CACHE_SUPERBLOCK_MAGIC);

	disk_super->version = cpu_to_le32(CACHE_VERSION);

	disk_super->version = cpu_to_le32(MAX_CACHE_VERSION);

	memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name));

	memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version));

	disk_super->policy_hint_size = 0;