From patchwork Thu Oct 15 00:31:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 11838329 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A7EB815E6 for ; Thu, 15 Oct 2020 00:31:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 897AB22241 for ; Thu, 15 Oct 2020 00:31:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="TZYAVcmx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732170AbgJOAb3 (ORCPT ); Wed, 14 Oct 2020 20:31:29 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:56030 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727790AbgJOAb3 (ORCPT ); Wed, 14 Oct 2020 20:31:29 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09F0U0vj056610; Thu, 15 Oct 2020 00:31:24 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : in-reply-to : references : mime-version : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=rgzakw6Kfk9akyvsSG3kcBBgBwnxeVj9VjaCBl4MSRo=; b=TZYAVcmx7F//dYLw1qiIfhnJ8ZyeHGu5TX2dU6U6tVNyh4+m+xlaCzuU9Pz4x1uhKH4k 3OjKzB26wRiIwtfBhv1UL95UbPPIPRc8IMp4RslpV9YmfRu1ENXVe8ucmBwzqD6WNexa FSsoXDT1p3neTqoYVoStq+LcqysvlA6+YWqdzKc6LsRDEWFEOKo+YB1oQUYyfWX6lK9o uagnXaA/mPUTRyTNbkwY7RUdFhjfjs1q5IarBGIzvZvofjl1dLoxECiAJ1r7Siyc7yMJ i3HVmDH7G3gKY+pSCdBhbSSv8mw5wMO1V+UY8Xl6QvUA4K7+CQJVV//3hPnCOv7/NPp4 iQ== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by userp2120.oracle.com with ESMTP id 343vaegms1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 15 Oct 2020 00:31:24 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09F0Tajk159088; Thu, 15 Oct 2020 00:31:24 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3020.oracle.com with ESMTP id 344by4dpth-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 15 Oct 2020 00:31:23 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 09F0VMFq007707; Thu, 15 Oct 2020 00:31:22 GMT Received: from localhost (/10.159.142.84) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 14 Oct 2020 17:31:22 -0700 Subject: [PATCH 1/2] vfs: move generic_remap_checks out of mm From: "Darrick J. Wong" To: darrick.wong@oracle.com, akpm@linux-foundation.org, viro@zeniv.linux.org.uk, torvalds@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Date: Wed, 14 Oct 2020 17:31:21 -0700 Message-ID: <160272188127.913987.8729718777463390497.stgit@magnolia> In-Reply-To: <160272187483.913987.4254237066433242737.stgit@magnolia> References: <160272187483.913987.4254237066433242737.stgit@magnolia> User-Agent: StGit/0.19 MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9774 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 spamscore=0 suspectscore=0 mlxscore=0 malwarescore=0 adultscore=0 bulkscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010150001 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9774 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 clxscore=1015 impostorscore=0 phishscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 mlxscore=0 suspectscore=0 spamscore=0 adultscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010150001 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Darrick J. Wong I would like to move all the generic helpers for the vfs remap range functionality (aka clonerange and dedupe) into a separate file so that they won't be scattered across the vfs and the mm subsystems. The eventual goal is to be able to deselect remap_range.c if none of the filesystems need that code, but the tricky part here is picking a stable(ish) part of the merge window to rearrange code. Signed-off-by: Darrick J. Wong --- fs/Makefile | 3 +- fs/remap_range.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 2 + mm/filemap.c | 81 +---------------------------------------- 4 files changed, 108 insertions(+), 81 deletions(-) create mode 100644 fs/remap_range.c diff --git a/fs/Makefile b/fs/Makefile index 1c7b0e3f6daa..7173350739c5 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -13,7 +13,8 @@ obj-y := open.o read_write.o file_table.o super.o \ seq_file.o xattr.o libfs.o fs-writeback.o \ pnode.o splice.o sync.o utimes.o d_path.o \ stack.o fs_struct.o statfs.o fs_pin.o nsfs.o \ - fs_types.o fs_context.o fs_parser.o fsopen.o init.o + fs_types.o fs_context.o fs_parser.o fsopen.o init.o \ + remap_range.o ifeq ($(CONFIG_BLOCK),y) obj-y += buffer.o block_dev.o direct-io.o mpage.o diff --git a/fs/remap_range.c b/fs/remap_range.c new file mode 100644 index 000000000000..e66d8c131b69 --- /dev/null +++ b/fs/remap_range.c @@ -0,0 +1,103 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/remap_range.c + * + * Copyright (C) 1994-1999 Linus Torvalds + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +#include +#include + +/* + * Performs necessary checks before doing a clone. + * + * Can adjust amount of bytes to clone via @req_count argument. + * Returns appropriate error code that caller should return or + * zero in case the clone should be allowed. + */ +int generic_remap_checks(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + loff_t *req_count, unsigned int remap_flags) +{ + struct inode *inode_in = file_in->f_mapping->host; + struct inode *inode_out = file_out->f_mapping->host; + uint64_t count = *req_count; + uint64_t bcount; + loff_t size_in, size_out; + loff_t bs = inode_out->i_sb->s_blocksize; + int ret; + + /* The start of both ranges must be aligned to an fs block. */ + if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_out, bs)) + return -EINVAL; + + /* Ensure offsets don't wrap. */ + if (pos_in + count < pos_in || pos_out + count < pos_out) + return -EINVAL; + + size_in = i_size_read(inode_in); + size_out = i_size_read(inode_out); + + /* Dedupe requires both ranges to be within EOF. */ + if ((remap_flags & REMAP_FILE_DEDUP) && + (pos_in >= size_in || pos_in + count > size_in || + pos_out >= size_out || pos_out + count > size_out)) + return -EINVAL; + + /* Ensure the infile range is within the infile. */ + if (pos_in >= size_in) + return -EINVAL; + count = min(count, size_in - (uint64_t)pos_in); + + ret = generic_write_check_limits(file_out, pos_out, &count); + if (ret) + return ret; + + /* + * If the user wanted us to link to the infile's EOF, round up to the + * next block boundary for this check. + * + * Otherwise, make sure the count is also block-aligned, having + * already confirmed the starting offsets' block alignment. + */ + if (pos_in + count == size_in) { + bcount = ALIGN(size_in, bs) - pos_in; + } else { + if (!IS_ALIGNED(count, bs)) + count = ALIGN_DOWN(count, bs); + bcount = count; + } + + /* Don't allow overlapped cloning within the same file. */ + if (inode_in == inode_out && + pos_out + bcount > pos_in && + pos_out < pos_in + bcount) + return -EINVAL; + + /* + * We shortened the request but the caller can't deal with that, so + * bounce the request back to userspace. + */ + if (*req_count != count && !(remap_flags & REMAP_FILE_CAN_SHORTEN)) + return -EINVAL; + + *req_count = count; + return 0; +} diff --git a/include/linux/fs.h b/include/linux/fs.h index 7519ae003a08..eea754a8dd67 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3012,6 +3012,8 @@ extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *); extern int generic_remap_checks(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t *count, unsigned int remap_flags); +extern int generic_write_check_limits(struct file *file, loff_t pos, + loff_t *count); extern int generic_file_rw_checks(struct file *file_in, struct file *file_out); extern int generic_copy_file_checks(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, diff --git a/mm/filemap.c b/mm/filemap.c index 99c49eeae71b..cf20e5aeb11b 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3098,8 +3098,7 @@ EXPORT_SYMBOL(read_cache_page_gfp); * LFS limits. If pos is under the limit it becomes a short access. If it * exceeds the limit we return -EFBIG. */ -static int generic_write_check_limits(struct file *file, loff_t pos, - loff_t *count) +int generic_write_check_limits(struct file *file, loff_t pos, loff_t *count) { struct inode *inode = file->f_mapping->host; loff_t max_size = inode->i_sb->s_maxbytes; @@ -3161,84 +3160,6 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) } EXPORT_SYMBOL(generic_write_checks); -/* - * Performs necessary checks before doing a clone. - * - * Can adjust amount of bytes to clone via @req_count argument. - * Returns appropriate error code that caller should return or - * zero in case the clone should be allowed. - */ -int generic_remap_checks(struct file *file_in, loff_t pos_in, - struct file *file_out, loff_t pos_out, - loff_t *req_count, unsigned int remap_flags) -{ - struct inode *inode_in = file_in->f_mapping->host; - struct inode *inode_out = file_out->f_mapping->host; - uint64_t count = *req_count; - uint64_t bcount; - loff_t size_in, size_out; - loff_t bs = inode_out->i_sb->s_blocksize; - int ret; - - /* The start of both ranges must be aligned to an fs block. */ - if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_out, bs)) - return -EINVAL; - - /* Ensure offsets don't wrap. */ - if (pos_in + count < pos_in || pos_out + count < pos_out) - return -EINVAL; - - size_in = i_size_read(inode_in); - size_out = i_size_read(inode_out); - - /* Dedupe requires both ranges to be within EOF. */ - if ((remap_flags & REMAP_FILE_DEDUP) && - (pos_in >= size_in || pos_in + count > size_in || - pos_out >= size_out || pos_out + count > size_out)) - return -EINVAL; - - /* Ensure the infile range is within the infile. */ - if (pos_in >= size_in) - return -EINVAL; - count = min(count, size_in - (uint64_t)pos_in); - - ret = generic_write_check_limits(file_out, pos_out, &count); - if (ret) - return ret; - - /* - * If the user wanted us to link to the infile's EOF, round up to the - * next block boundary for this check. - * - * Otherwise, make sure the count is also block-aligned, having - * already confirmed the starting offsets' block alignment. - */ - if (pos_in + count == size_in) { - bcount = ALIGN(size_in, bs) - pos_in; - } else { - if (!IS_ALIGNED(count, bs)) - count = ALIGN_DOWN(count, bs); - bcount = count; - } - - /* Don't allow overlapped cloning within the same file. */ - if (inode_in == inode_out && - pos_out + bcount > pos_in && - pos_out < pos_in + bcount) - return -EINVAL; - - /* - * We shortened the request but the caller can't deal with that, so - * bounce the request back to userspace. - */ - if (*req_count != count && !(remap_flags & REMAP_FILE_CAN_SHORTEN)) - return -EINVAL; - - *req_count = count; - return 0; -} - - /* * Performs common checks before doing a file copy/clone * from @file_in to @file_out.