From patchwork Mon Jun 15 12:53:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11604841 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 127111392 for ; Mon, 15 Jun 2020 12:54:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE75C2078E for ; Mon, 15 Jun 2020 12:54:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="W+HJGLEF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730213AbgFOMyW (ORCPT ); Mon, 15 Jun 2020 08:54:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730165AbgFOMx7 (ORCPT ); Mon, 15 Jun 2020 08:53:59 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE3BDC061A0E; Mon, 15 Jun 2020 05:53:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=w36WFTF/YYDj+vMMm5K/rSmIM+0T4bCCxz1vwgNGFpA=; b=W+HJGLEFJ+lhk60iQ5Bzln2Y0z 4E4rSTrm4G+fl4WB3kG6VKhq7JRX1NOxJ4VDudQcbfuWr6MiK8UHjnLd5rDua/GpVNvJk9tPxn93r vgDrlTV//pm4B2rsiiFdzeim5d38Bp9wr42ouCpN2TC+J0exS0D+NKzAMZkNPjh9utXIG2jfIM7V3 nZBhK9WSrv39wMXP9rsnw6F9ir6S/8XGWUf3c9HqQ9suZsJOhlu6rldb8fTilzIwrIoWJ4pZgE/Ki tFnXFUau0lpagcsbA18pZKgoAB/kP7rytdHoXz/50+NGRqVVoA9KyvyHEz5XlNLmQPBl9LPhdc08n glFWbDpg==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkocg-0000vw-DE; Mon, 15 Jun 2020 12:53:58 +0000 From: Christoph Hellwig To: linux-kernel@vger.kernel.org Cc: "H. Peter Anvin" , Song Liu , Al Viro , Linus Torvalds , linux-raid@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 14/16] initramfs: switch initramfs unpacking to struct file based APIs Date: Mon, 15 Jun 2020 14:53:21 +0200 Message-Id: <20200615125323.930983-15-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200615125323.930983-1-hch@lst.de> References: <20200615125323.930983-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org There is no good reason to mess with file descriptors from in-kernel code, switch the initramfs unpacking to struct file based write instead. As we don't have nice helper for chmod or chown on a struct file or struct path use the pathname based ones instead there. This causes additional (cached) lookups, but keeps the code much simpler. Signed-off-by: Christoph Hellwig --- fs/open.c | 7 +------ include/linux/syscalls.h | 1 - init/initramfs.c | 42 ++++++++++++++++++++-------------------- 3 files changed, 22 insertions(+), 28 deletions(-) diff --git a/fs/open.c b/fs/open.c index 6cd48a61cda3b9..6348173532e663 100644 --- a/fs/open.c +++ b/fs/open.c @@ -602,7 +602,7 @@ static int chmod_common(const struct path *path, umode_t mode) return error; } -int ksys_fchmod(unsigned int fd, umode_t mode) +SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode) { struct fd f = fdget(fd); int err = -EBADF; @@ -615,11 +615,6 @@ int ksys_fchmod(unsigned int fd, umode_t mode) return err; } -SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode) -{ - return ksys_fchmod(fd, mode); -} - int do_fchmodat(int dfd, const char __user *filename, umode_t mode) { struct path path; diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 005463f5acc23d..5215bd413b6eb1 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1241,7 +1241,6 @@ int ksys_dup(unsigned int fildes); int ksys_chroot(const char __user *filename); ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count); int ksys_chdir(const char __user *filename); -int ksys_fchmod(unsigned int fd, umode_t mode); int ksys_fchown(unsigned int fd, uid_t user, gid_t group); int ksys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg); ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count); diff --git a/init/initramfs.c b/init/initramfs.c index d42ec8329cd840..2d2f433ac7f01b 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -13,13 +13,13 @@ #include #include -static ssize_t __init xwrite(int fd, const char *p, size_t count) +static ssize_t __init xwrite(struct file *file, const char *p, size_t count) { ssize_t out = 0; /* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */ while (count) { - ssize_t rv = ksys_write(fd, p, count); + ssize_t rv = kernel_write(file, p, count, &file->f_pos); if (rv < 0) { if (rv == -EINTR || rv == -EAGAIN) @@ -317,7 +317,7 @@ static int __init maybe_link(void) return 0; } -static __initdata int wfd; +static __initdata struct file *wfile; static int __init do_name(void) { @@ -334,16 +334,16 @@ static int __init do_name(void) int openflags = O_WRONLY|O_CREAT; if (ml != 1) openflags |= O_TRUNC; - wfd = ksys_open(collected, openflags, mode); - - if (wfd >= 0) { - ksys_fchown(wfd, uid, gid); - ksys_fchmod(wfd, mode); - if (body_len) - ksys_ftruncate(wfd, body_len); - vcollected = kstrdup(collected, GFP_KERNEL); - state = CopyFile; - } + wfile = filp_open(collected, openflags, mode); + if (IS_ERR(wfile)) + return 0; + + ksys_chown(collected, uid, gid); + ksys_chmod(collected, mode); + if (body_len) + vfs_truncate(&wfile->f_path, body_len); + vcollected = kstrdup(collected, GFP_KERNEL); + state = CopyFile; } } else if (S_ISDIR(mode)) { ksys_mkdir(collected, mode); @@ -365,16 +365,16 @@ static int __init do_name(void) static int __init do_copy(void) { if (byte_count >= body_len) { - if (xwrite(wfd, victim, body_len) != body_len) + if (xwrite(wfile, victim, body_len) != body_len) error("write error"); - ksys_close(wfd); + fput(wfile); do_utime(vcollected, mtime); kfree(vcollected); eat(body_len); state = SkipIt; return 0; } else { - if (xwrite(wfd, victim, byte_count) != byte_count) + if (xwrite(wfile, victim, byte_count) != byte_count) error("write error"); body_len -= byte_count; eat(byte_count); @@ -586,21 +586,21 @@ static void __init clean_rootfs(void) static void __init populate_initrd_image(char *err) { ssize_t written; - int fd; + struct file *file; unpack_to_rootfs(__initramfs_start, __initramfs_size); printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n", err); - fd = ksys_open("/initrd.image", O_WRONLY | O_CREAT, 0700); - if (fd < 0) + file = filp_open("/initrd.image", O_WRONLY | O_CREAT, 0700); + if (IS_ERR(file)) return; - written = xwrite(fd, (char *)initrd_start, initrd_end - initrd_start); + written = xwrite(file, (char *)initrd_start, initrd_end - initrd_start); if (written != initrd_end - initrd_start) pr_err("/initrd.image: incomplete write (%zd != %ld)\n", written, initrd_end - initrd_start); - ksys_close(fd); + fput(file); } #endif /* CONFIG_BLK_DEV_RAM */