From patchwork Thu Feb 10 19:09:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 12742334 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2FE0AC433FE for ; Thu, 10 Feb 2022 19:10:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343721AbiBJTKc (ORCPT ); Thu, 10 Feb 2022 14:10:32 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:48148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343710AbiBJTKb (ORCPT ); Thu, 10 Feb 2022 14:10:31 -0500 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D61F210BA for ; Thu, 10 Feb 2022 11:10:32 -0800 (PST) Received: by mail-pj1-x1032.google.com with SMTP id c5-20020a17090a1d0500b001b904a7046dso8012377pjd.1 for ; Thu, 10 Feb 2022 11:10:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osandov-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=uOABk8mNzBKfgcWHyLCqTK+OXP9+oV+Aq9izhbHg64Q=; b=V0p1ePfjpZ7FSs49PS6VmQzcdHMQoEK0IXwS6Yjox3GLNfNM8Hzil+TvU5a6JTmBjd Ygo5B6xmzYd0yO89/z4p+yR8Ge+DFwTD+C9mBaks2yx12erVU5PFqqvKCeLsKXJxpYRX 6U3IYt4pT16djU3ZzrvgEVE8KURXLbN3cm1dsBNSOCV3ZDzRtPOLjjk0EeyYppAF+dK3 +WeecVq8FnpUTEYEK0qcBO01JCagsmVehBDI7HL/TzImXWwcHNYyovKLd922G+e2FYKQ 3ESV4D6Ft+2z2nqibN6BgWCjufs1BRI3T7uHTvgP7P5qI80WYTL+t25BzTiY6u4bCTE1 IN6w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=uOABk8mNzBKfgcWHyLCqTK+OXP9+oV+Aq9izhbHg64Q=; b=EHlEiYRnBHulJfNVwOakWIqSypBwMFMjNJvH5ukoodFQ5yyIfPhOFUvWmTwqqRaDPw AktVbqOdP6hcy9R51QneiM8C1YwtGurGJBewWgCwK+cudrnIAH80uPHIFWTiUR419xKf KrhUu5IDy3Ovc69056cRlMOD5qcbEUB3p1bMPBIZ+kUKTYIXakCOlUss/lpr/1zEqsBb SOiEllhln8vuxgEbRLBNKgQjYiNwKMOLvBh++iB6tr8bn2xLwz6bL7W9mP+w4GwdPOs9 8Ue0mQ8nZKjbU8YK9g7ZWewIGDLLdF9bzIB3BBKPCPuw2E8D09QIkTnAI0CQ0Xe32FYn 6XgQ== X-Gm-Message-State: AOAM530GMv78UUf+G5LxzNEKtF9JKtiCJH6kPYQ/YVmJQqLV43hptbCe 9JBnb2CUHaFCGLhZIZxouy+ghdU6nfUGvQ== X-Google-Smtp-Source: ABdhPJw0oMLy3q5Y5HJpwHL0N5ip3O/txBx8ukVa2+JFPlbV6SPwf0bkSFylYQD1772PRWonC8RwDA== X-Received: by 2002:a17:902:ce02:: with SMTP id k2mr5463858plg.93.1644520231898; Thu, 10 Feb 2022 11:10:31 -0800 (PST) Received: from relinquished.tfbnw.net ([2620:10d:c090:400::5:1975]) by smtp.gmail.com with ESMTPSA id n5sm8315898pgt.22.2022.02.10.11.10.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Feb 2022 11:10:31 -0800 (PST) From: Omar Sandoval To: linux-btrfs@vger.kernel.org Cc: kernel-team@fb.com Subject: [PATCH v13 02/17] fs: export variant of generic_write_checks without iov_iter Date: Thu, 10 Feb 2022 11:09:52 -0800 Message-Id: X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Omar Sandoval Encoded I/O in Btrfs needs to check a write with a given logical size without an iov_iter that matches that size (because the iov_iter we have is for the compressed data). So, factor out the parts of generic_write_check() that don't need an iov_iter into a new generic_write_checks_count() function and export that. Reviewed-by: Nikolay Borisov Signed-off-by: Omar Sandoval --- fs/read_write.c | 33 ++++++++++++++++++++------------- include/linux/fs.h | 1 + 2 files changed, 21 insertions(+), 13 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 4d60146243df..dc5000173b80 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1618,24 +1618,16 @@ int generic_write_check_limits(struct file *file, loff_t pos, loff_t *count) return 0; } -/* - * Performs necessary checks before doing a write - * - * Can adjust writing position or amount of bytes to write. - * Returns appropriate error code that caller should return or - * zero in case that write should be allowed. - */ -ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) +/* Like generic_write_checks(), but takes size of write instead of iter. */ +int generic_write_checks_count(struct kiocb *iocb, loff_t *count) { struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; - loff_t count; - int ret; if (IS_SWAPFILE(inode)) return -ETXTBSY; - if (!iov_iter_count(from)) + if (!*count) return 0; /* FIXME: this is for backwards compatibility with 2.4 */ @@ -1645,8 +1637,23 @@ ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) return -EINVAL; - count = iov_iter_count(from); - ret = generic_write_check_limits(file, iocb->ki_pos, &count); + return generic_write_check_limits(iocb->ki_filp, iocb->ki_pos, count); +} +EXPORT_SYMBOL(generic_write_checks_count); + +/* + * Performs necessary checks before doing a write + * + * Can adjust writing position or amount of bytes to write. + * Returns appropriate error code that caller should return or + * zero in case that write should be allowed. + */ +ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) +{ + loff_t count = iov_iter_count(from); + int ret; + + ret = generic_write_checks_count(iocb, &count); if (ret) return ret; diff --git a/include/linux/fs.h b/include/linux/fs.h index 4deb42c326ba..ce5aabb609cd 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3130,6 +3130,7 @@ extern int sb_min_blocksize(struct super_block *, int); extern int generic_file_mmap(struct file *, struct vm_area_struct *); extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *); extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *); +extern int generic_write_checks_count(struct kiocb *iocb, loff_t *count); 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);