From patchwork Wed Oct 10 00:14:11 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 10633689 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7D1F516B1 for ; Wed, 10 Oct 2018 00:14:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6A3D6284C9 for ; Wed, 10 Oct 2018 00:14:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5E2F128F95; Wed, 10 Oct 2018 00:14:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from userp2130.oracle.com (userp2130.oracle.com [156.151.31.86]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CCD36284C9 for ; Wed, 10 Oct 2018 00:14:30 +0000 (UTC) Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9A0DcuL123098; Wed, 10 Oct 2018 00:14:17 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : date : message-id : in-reply-to : references : mime-version : cc : subject : list-id : list-unsubscribe : list-archive : list-post : list-help : list-subscribe : content-type : content-transfer-encoding : sender; s=corp-2018-07-02; bh=PWx4LGC5FxtpbyVexc8/ukOBr2BS4lzpSpIIePm1JF4=; b=XQyqZExKtBQvWG+LbBOZfBFODylB7JH7MmY3ESCDIbxxu02lDure6NcW+HLl9d218myc NC2tGWEeQETwur684o3nJ8Hxfh1PC2STpSAIV/a4hQrc2stP9Noe/T3Az6V9uiNueuB5 vfXkR4DfDsdCnTVaxmQUy/nzMNaVFNRUNJQPQZ3hvI82EnAhClXAb/mcfpEoQYJVgabN oEphau7l94acaAH3Mub7SOmTdtHojbjuTJVDgB/ZPlZYxHWZHqOm7KKvsGYAPKYmxeVs D+v+/XkF8aMwm+vm3fy5hGSPiAzC0QiQwYjMZpeC+/ky+yGUB/ohTe6lKKlOWqDKBCY2 7A== Received: from aserv0022.oracle.com (aserv0022.oracle.com [141.146.126.234]) by userp2130.oracle.com with ESMTP id 2mxmftrvs4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 10 Oct 2018 00:14:16 +0000 Received: from oss.oracle.com (oss-old-reserved.oracle.com [137.254.22.2]) by aserv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w9A0EFlQ031370 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 10 Oct 2018 00:14:15 GMT Received: from localhost ([127.0.0.1] helo=lb-oss.oracle.com) by oss.oracle.com with esmtp (Exim 4.63) (envelope-from ) id 1gA28l-0003Rn-Qr; Tue, 09 Oct 2018 17:14:15 -0700 Received: from aserv0021.oracle.com ([141.146.126.233]) by oss.oracle.com with esmtp (Exim 4.63) (envelope-from ) id 1gA28k-0003RM-5g for ocfs2-devel@oss.oracle.com; Tue, 09 Oct 2018 17:14:14 -0700 Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w9A0EDdB032636 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 10 Oct 2018 00:14:14 GMT Received: from abhmp0006.oracle.com (abhmp0006.oracle.com [141.146.116.12]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w9A0ECSo021892; Wed, 10 Oct 2018 00:14:13 GMT Received: from localhost (/10.159.249.114) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 10 Oct 2018 00:14:12 +0000 From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Date: Tue, 09 Oct 2018 17:14:11 -0700 Message-ID: <153913045111.32295.15783645423071362029.stgit@magnolia> In-Reply-To: <153913023835.32295.13962696655740190941.stgit@magnolia> References: <153913023835.32295.13962696655740190941.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, ocfs2-devel@oss.oracle.com, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org Subject: [Ocfs2-devel] [PATCH 19/25] vfs: hide file range comparison function X-BeenThere: ocfs2-devel@oss.oracle.com X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: ocfs2-devel-bounces@oss.oracle.com Errors-To: ocfs2-devel-bounces@oss.oracle.com X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9041 signatures=668706 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810100001 X-Virus-Scanned: ClamAV using ClamSMTP From: Darrick J. Wong There are no callers of vfs_dedupe_file_range_compare, so we might as well make it a static helper and remove the export. Signed-off-by: Darrick J. Wong --- fs/read_write.c | 191 ++++++++++++++++++++++++++-------------------------- include/linux/fs.h | 3 - 2 files changed, 95 insertions(+), 99 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 8ed0aed81649..57627202bd50 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1714,6 +1714,101 @@ static int remap_verify_area(struct file *file, loff_t pos, loff_t len, return security_file_permission(file, write ? MAY_WRITE : MAY_READ); } +/* + * Read a page's worth of file data into the page cache. Return the page + * locked. + */ +static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) +{ + struct address_space *mapping; + struct page *page; + pgoff_t n; + + n = offset >> PAGE_SHIFT; + mapping = inode->i_mapping; + page = read_mapping_page(mapping, n, NULL); + if (IS_ERR(page)) + return page; + if (!PageUptodate(page)) { + put_page(page); + return ERR_PTR(-EIO); + } + lock_page(page); + return page; +} + +/* + * Compare extents of two files to see if they are the same. + * Caller must have locked both inodes to prevent write races. + */ +static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, + struct inode *dest, loff_t destoff, + loff_t len, bool *is_same) +{ + loff_t src_poff; + loff_t dest_poff; + void *src_addr; + void *dest_addr; + struct page *src_page; + struct page *dest_page; + loff_t cmp_len; + bool same; + int error; + + error = -EINVAL; + same = true; + while (len) { + src_poff = srcoff & (PAGE_SIZE - 1); + dest_poff = destoff & (PAGE_SIZE - 1); + cmp_len = min(PAGE_SIZE - src_poff, + PAGE_SIZE - dest_poff); + cmp_len = min(cmp_len, len); + if (cmp_len <= 0) + goto out_error; + + src_page = vfs_dedupe_get_page(src, srcoff); + if (IS_ERR(src_page)) { + error = PTR_ERR(src_page); + goto out_error; + } + dest_page = vfs_dedupe_get_page(dest, destoff); + if (IS_ERR(dest_page)) { + error = PTR_ERR(dest_page); + unlock_page(src_page); + put_page(src_page); + goto out_error; + } + src_addr = kmap_atomic(src_page); + dest_addr = kmap_atomic(dest_page); + + flush_dcache_page(src_page); + flush_dcache_page(dest_page); + + if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) + same = false; + + kunmap_atomic(dest_addr); + kunmap_atomic(src_addr); + unlock_page(dest_page); + unlock_page(src_page); + put_page(dest_page); + put_page(src_page); + + if (!same) + break; + + srcoff += cmp_len; + destoff += cmp_len; + len -= cmp_len; + } + + *is_same = same; + return 0; + +out_error: + return error; +} + /* * Check that the two inodes are eligible for cloning, the ranges make * sense, and then flush all dirty data. Caller must ensure that the @@ -1887,102 +1982,6 @@ loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, } EXPORT_SYMBOL(vfs_clone_file_range); -/* - * Read a page's worth of file data into the page cache. Return the page - * locked. - */ -static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset) -{ - struct address_space *mapping; - struct page *page; - pgoff_t n; - - n = offset >> PAGE_SHIFT; - mapping = inode->i_mapping; - page = read_mapping_page(mapping, n, NULL); - if (IS_ERR(page)) - return page; - if (!PageUptodate(page)) { - put_page(page); - return ERR_PTR(-EIO); - } - lock_page(page); - return page; -} - -/* - * Compare extents of two files to see if they are the same. - * Caller must have locked both inodes to prevent write races. - */ -int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, - struct inode *dest, loff_t destoff, - loff_t len, bool *is_same) -{ - loff_t src_poff; - loff_t dest_poff; - void *src_addr; - void *dest_addr; - struct page *src_page; - struct page *dest_page; - loff_t cmp_len; - bool same; - int error; - - error = -EINVAL; - same = true; - while (len) { - src_poff = srcoff & (PAGE_SIZE - 1); - dest_poff = destoff & (PAGE_SIZE - 1); - cmp_len = min(PAGE_SIZE - src_poff, - PAGE_SIZE - dest_poff); - cmp_len = min(cmp_len, len); - if (cmp_len <= 0) - goto out_error; - - src_page = vfs_dedupe_get_page(src, srcoff); - if (IS_ERR(src_page)) { - error = PTR_ERR(src_page); - goto out_error; - } - dest_page = vfs_dedupe_get_page(dest, destoff); - if (IS_ERR(dest_page)) { - error = PTR_ERR(dest_page); - unlock_page(src_page); - put_page(src_page); - goto out_error; - } - src_addr = kmap_atomic(src_page); - dest_addr = kmap_atomic(dest_page); - - flush_dcache_page(src_page); - flush_dcache_page(dest_page); - - if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) - same = false; - - kunmap_atomic(dest_addr); - kunmap_atomic(src_addr); - unlock_page(dest_page); - unlock_page(src_page); - put_page(dest_page); - put_page(src_page); - - if (!same) - break; - - srcoff += cmp_len; - destoff += cmp_len; - len -= cmp_len; - } - - *is_same = same; - return 0; - -out_error: - return error; -} -EXPORT_SYMBOL(vfs_dedupe_file_range_compare); - loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, struct file *dst_file, loff_t dst_pos, loff_t len, unsigned int remap_flags) diff --git a/include/linux/fs.h b/include/linux/fs.h index e0494d719ebc..9c53276979bb 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1846,9 +1846,6 @@ extern loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, extern loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t len, unsigned int remap_flags); -extern int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff, - struct inode *dest, loff_t destoff, - loff_t len, bool *is_same); extern int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same); extern loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,