From 6d97c6e31b553bc9f58b83ac3c4c79c17affbda8 Mon Sep 17 00:00:00 2001
From: Johannes Thumshirn <jthumshirn@suse.de>
Date: Mon, 3 Jun 2019 16:58:56 +0200
Subject: [PATCH] btrfs: add boilerplate code for directly including the crypto
framework
Add boilerplate code for directly including the crypto framework. This
helps us flipping the switch for new algorithms.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/ctree.h | 8 ++++++++
fs/btrfs/disk-io.c | 46 +++++++++++++++++++++++++++++++++++++++-------
2 files changed, 47 insertions(+), 7 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index a66ed58058d94..2e908c557fb25 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 const char *btrfs_csum_names[] = { "crc32c" };
#define BTRFS_EMPTY_DIR_SIZE 0
@@ -1163,6 +1164,8 @@ struct btrfs_fs_info {
spinlock_t swapfile_pins_lock;
struct rb_root swapfile_pins;
+ struct crypto_shash *csum_shash;
+
#ifdef CONFIG_BTRFS_FS_REF_VERIFY
spinlock_t ref_verify_lock;
struct rb_root block_tree;
@@ -2454,6 +2457,11 @@ static inline int btrfs_super_csum_size(const struct btrfs_super_block *s)
return btrfs_csum_sizes[t];
}
+static inline const char *btrfs_super_csum_name(u16 csum_type)
+{
+ /* csum type is validated at mount time */
+ return btrfs_csum_names[csum_type];
+}
/*
* 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 c9ce0b0020084..34222bbe4b482 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"
@@ -2256,6 +2257,29 @@ 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, u16 csum_type)
+{
+ struct crypto_shash *csum_shash;
+ const char *csum_name = btrfs_super_csum_name(csum_type);
+
+ csum_shash = crypto_alloc_shash(csum_name, 0, 0);
+
+ if (IS_ERR(csum_shash)) {
+ btrfs_err(fs_info, "error allocating %s hash for checksum",
+ 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)
{
@@ -2820,6 +2844,12 @@ int open_ctree(struct super_block *sb,
goto fail_alloc;
}
+ ret = btrfs_init_csum_hash(fs_info, csum_type);
+ 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).
@@ -2828,7 +2858,7 @@ int open_ctree(struct super_block *sb,
btrfs_err(fs_info, "superblock checksum mismatch");
err = -EINVAL;
brelse(bh);
- goto fail_alloc;
+ goto fail_csum;
}
/*
@@ -2865,11 +2895,11 @@ 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)
@@ -2891,7 +2921,7 @@ 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) &
@@ -2901,7 +2931,7 @@ 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);
@@ -2945,7 +2975,7 @@ 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;
}
/*
@@ -2961,7 +2991,7 @@ 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);
@@ -3339,6 +3369,8 @@ 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);