From: Wang Xiaoguang <wangxg.f...@cn.fujitsu.com>
Unlike in-memory or on-disk dedupe method, only SHA256 hash method is
supported yet, so implement btrfs_dedupe_calc_hash() interface using
SHA256.
Signed-off-by: Qu Wenruo <quwen...@cn.fujitsu.com>
Signed-off-by: Wang Xiaoguang <wangxg.f...@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jba...@fb.com>
Signed-off-by: Lu Fengqi <lufq.f...@cn.fujitsu.com>
---
fs/btrfs/dedupe.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)
diff --git a/fs/btrfs/dedupe.c b/fs/btrfs/dedupe.c
index 03ad41423c01..6199215022e6 100644
--- a/fs/btrfs/dedupe.c
+++ b/fs/btrfs/dedupe.c
@@ -644,3 +644,53 @@ int btrfs_dedupe_search(struct btrfs_fs_info *fs_info,
}
return ret;
}
+
+int btrfs_dedupe_calc_hash(struct btrfs_fs_info *fs_info,
+ struct inode *inode, u64 start,
+ struct btrfs_dedupe_hash *hash)
+{
+ int i;
+ int ret;
+ struct page *p;
+ struct shash_desc *shash;
+ struct btrfs_dedupe_info *dedupe_info = fs_info->dedupe_info;
+ struct crypto_shash *tfm = dedupe_info->dedupe_driver;
+ u64 dedupe_bs;
+ u64 sectorsize = fs_info->sectorsize;
+
+ shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(tfm), GFP_NOFS);
+ if (!shash)
+ return -ENOMEM;
+
+ if (!fs_info->dedupe_enabled || !hash)
+ return 0;
+
+ if (WARN_ON(dedupe_info == NULL))
+ return -EINVAL;
+
+ WARN_ON(!IS_ALIGNED(start, sectorsize));
+
+ dedupe_bs = dedupe_info->blocksize;
+
+ shash->tfm = tfm;
+ shash->flags = 0;
+ ret = crypto_shash_init(shash);
+ if (ret)
+ return ret;
+ for (i = 0; sectorsize * i < dedupe_bs; i++) {
+ char *d;
+
+ p = find_get_page(inode->i_mapping,
+ (start >> PAGE_SHIFT) + i);
+ if (WARN_ON(!p))
+ return -ENOENT;
+ d = kmap(p);
+ ret = crypto_shash_update(shash, d, sectorsize);
+ kunmap(p);
+ put_page(p);
+ if (ret)
+ return ret;
+ }
+ ret = crypto_shash_final(shash, hash->hash);
+ return ret;
+}
--
2.19.1
