From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:65010 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752007AbcBBDIC (ORCPT ); Mon, 1 Feb 2016 22:08:02 -0500 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: Wang Xiaoguang Subject: [PATCH v5 07/19] btrfs: dedup: Implement btrfs_dedup_calc_hash interface Date: Tue, 2 Feb 2016 11:05:39 +0800 Message-Id: <1454382351-31775-8-git-send-email-quwenruo@cn.fujitsu.com> In-Reply-To: <1454382351-31775-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1454382351-31775-1-git-send-email-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Wang Xiaoguang Unlike in-memory or on-disk dedup method, only SHA256 hash method is supported yet, so implement btrfs_dedup_calc_hash() interface using SHA256. Signed-off-by: Qu Wenruo Signed-off-by: Wang Xiaoguang --- fs/btrfs/dedup.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/fs/btrfs/dedup.c b/fs/btrfs/dedup.c index 20749ce..f6b518a 100644 --- a/fs/btrfs/dedup.c +++ b/fs/btrfs/dedup.c @@ -516,3 +516,46 @@ int btrfs_dedup_search(struct btrfs_dedup_info *dedup_info, } return ret; } + +int btrfs_dedup_calc_hash(struct btrfs_dedup_info *dedup_info, + struct inode *inode, u64 start, + struct btrfs_dedup_hash *hash) +{ + int i; + int ret; + struct page *p; + struct crypto_shash *tfm = dedup_info->dedup_driver; + struct { + struct shash_desc desc; + char ctx[crypto_shash_descsize(tfm)]; + } sdesc; + u64 dedup_bs = dedup_info->blocksize; + u64 sectorsize = BTRFS_I(inode)->root->sectorsize; + + if (!dedup_info || !hash) + return 0; + + WARN_ON(!IS_ALIGNED(start, sectorsize)); + + sdesc.desc.tfm = tfm; + sdesc.desc.flags = 0; + ret = crypto_shash_init(&sdesc.desc); + if (ret) + return ret; + for (i = 0; sectorsize * i < dedup_bs; i++) { + char *d; + + p = find_get_page(inode->i_mapping, + (start >> PAGE_CACHE_SHIFT) + i); + if (WARN_ON(!p)) + return -ENOENT; + d = kmap(p); + ret = crypto_shash_update(&sdesc.desc, d, sectorsize); + kunmap(p); + page_cache_release(p); + if (ret) + return ret; + } + ret = crypto_shash_final(&sdesc.desc, hash->hash); + return ret; +} -- 2.7.0