On 10.05.19 г. 14:15 ч., Johannes Thumshirn wrote:
> Add boilerplate code for directly including the crypto framework.
>
> This helps us flipping the switch for new algorithms.
>
> Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
> ---
> fs/btrfs/ctree.h | 11 +++++++++++
> fs/btrfs/disk-io.c | 49 ++++++++++++++++++++++++++++++++++++++++++-------
> 2 files changed, 53 insertions(+), 7 deletions(-)
>
> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
> index e62934fb8748..8733c55ed686 100644
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -73,6 +73,7 @@ struct btrfs_ref;
>
> /* four bytes for CRC32 */
> static const int btrfs_csum_sizes[] = { 4 };
> +static char *btrfs_csum_names[] = { "crc32c" };
>
> #define BTRFS_EMPTY_DIR_SIZE 0
>
> @@ -1165,6 +1166,8 @@ struct btrfs_fs_info {
> spinlock_t ref_verify_lock;
> struct rb_root block_tree;
> #endif
> +
> + struct crypto_shash *csum_shash;
> };
>
> static inline struct btrfs_fs_info *btrfs_sb(struct super_block *sb)
> @@ -2452,6 +2455,14 @@ static inline int btrfs_super_csum_size(const struct btrfs_super_block *s)
> return btrfs_csum_sizes[t];
> }
>
> +static inline char *btrfs_super_csum_name(const struct btrfs_super_block *s)
> +{
> + u16 t = btrfs_super_csum_type(s);
> + /*
> + * csum type is validated at mount time
> + */
> + return btrfs_csum_names[t];
> +}
>
> /*
> * The leaf data grows from end-to-front in the node.
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 21ae9daf52b7..d57adf3eaa85 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -19,6 +19,7 @@
> #include <linux/crc32c.h>
> #include <linux/sched/mm.h>
> #include <asm/unaligned.h>
> +#include <crypto/hash.h>
> #include "ctree.h"
> #include "disk-io.h"
> #include "transaction.h"
> @@ -2261,6 +2262,30 @@ static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
> return 0;
> }
>
> +static int btrfs_init_csum_hash(struct btrfs_fs_info *fs_info,
> + struct btrfs_super_block *sb)
> +{
> + struct crypto_shash *csum_shash;
> + const char *csum_name = btrfs_super_csum_name(sb);
> +
> + csum_shash = crypto_alloc_shash(csum_name, 0, 0);
> +
> + if (IS_ERR(csum_shash)) {
> + btrfs_err(fs_info, "error allocating %s hash for checksum\n",
> + csum_name);
> + return PTR_ERR(csum_shash);
> + }
> +
> + fs_info->csum_shash = csum_shash;
> +
> + return 0;
> +}
> +
> +static void btrfs_free_csum_hash(struct btrfs_fs_info *fs_info)
> +{
> + crypto_free_shash(fs_info->csum_shash);
> +}
> +
> static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
> struct btrfs_fs_devices *fs_devices)
> {
> @@ -2819,6 +2844,14 @@ int open_ctree(struct super_block *sb,
> goto fail_alloc;
> }
>
> +
> + ret = btrfs_init_csum_hash(fs_info, (struct btrfs_super_block *)
> + bh->b_data);
> + if (ret) {
> + err = ret;
> + goto fail_alloc;
> + }
> +
> /*
> * We want to check superblock checksum, the type is stored inside.
> * Pass the whole disk block of size BTRFS_SUPER_INFO_SIZE (4k).
> @@ -2827,7 +2860,7 @@ int open_ctree(struct super_block *sb,
> btrfs_err(fs_info, "superblock checksum mismatch");
> err = -EINVAL;
> brelse(bh);
> - goto fail_alloc;
> + goto fail_csum;
> }
>
> /*
> @@ -2864,11 +2897,11 @@ int open_ctree(struct super_block *sb,
> if (ret) {
> btrfs_err(fs_info, "superblock contains fatal errors");
> err = -EINVAL;
> - goto fail_alloc;
> + goto fail_csum;
> }
>
> if (!btrfs_super_root(disk_super))
> - goto fail_alloc;
> + goto fail_csum;
>
> /* check FS state, whether FS is broken. */
> if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_ERROR)
> @@ -2890,7 +2923,7 @@ int open_ctree(struct super_block *sb,
> ret = btrfs_parse_options(fs_info, options, sb->s_flags);
> if (ret) {
> err = ret;
> - goto fail_alloc;
> + goto fail_csum;
> }
>
> features = btrfs_super_incompat_flags(disk_super) &
> @@ -2900,7 +2933,7 @@ int open_ctree(struct super_block *sb,
> "cannot mount because of unsupported optional features (%llx)",
> features);
> err = -EINVAL;
> - goto fail_alloc;
> + goto fail_csum;
> }
>
> features = btrfs_super_incompat_flags(disk_super);
> @@ -2944,7 +2977,7 @@ int open_ctree(struct super_block *sb,
> btrfs_err(fs_info,
> "unequal nodesize/sectorsize (%u != %u) are not allowed for mixed block groups",
> nodesize, sectorsize);
> - goto fail_alloc;
> + goto fail_csum;
> }
>
> /*
> @@ -2960,7 +2993,7 @@ int open_ctree(struct super_block *sb,
> "cannot mount read-write because of unsupported optional features (%llx)",
> features);
> err = -EINVAL;
> - goto fail_alloc;
> + goto fail_csum;
> }
>
> ret = btrfs_init_workqueues(fs_info, fs_devices);
> @@ -3338,6 +3371,8 @@ int open_ctree(struct super_block *sb,
> fail_sb_buffer:
> btrfs_stop_all_workers(fs_info);
> btrfs_free_block_groups(fs_info);
> +fail_csum:
> + btrfs_free_csum_hash(fs_info);
> fail_alloc:
> fail_iput:
> btrfs_mapping_tree_free(&fs_info->mapping_tree);
>
