From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932778AbeCOTGi (ORCPT ); Thu, 15 Mar 2018 15:06:38 -0400 Received: from isilmar-4.linta.de ([136.243.71.142]:36228 "EHLO isilmar-4.linta.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932694AbeCOTGZ (ORCPT ); Thu, 15 Mar 2018 15:06:25 -0400 From: Dominik Brodowski To: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, viro@zeniv.linux.org.uk Cc: luto@kernel.org, mingo@kernel.org, akpm@linux-foundation.org, arnd@arndb.de, linux-s390@vger.kernel.org Subject: [PATCH v2 18/36] fs: add ksys_write() helper; remove in-kernel calls to sys_write() Date: Thu, 15 Mar 2018 20:05:11 +0100 Message-Id: <20180315190529.20943-19-linux@dominikbrodowski.net> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180315190529.20943-1-linux@dominikbrodowski.net> References: <20180315190529.20943-1-linux@dominikbrodowski.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using this helper allows us to avoid the in-kernel calls to the sys_write() syscall. Cc: Alexander Viro Cc: linux-s390@vger.kernel.org Signed-off-by: Dominik Brodowski --- arch/s390/kernel/compat_linux.c | 2 +- fs/read_write.c | 9 +++++++-- include/linux/syscalls.h | 1 + init/do_mounts_rd.c | 4 ++-- init/initramfs.c | 2 +- 5 files changed, 12 insertions(+), 6 deletions(-) diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c index 79b7a3438d54..5a9cfde5fc28 100644 --- a/arch/s390/kernel/compat_linux.c +++ b/arch/s390/kernel/compat_linux.c @@ -468,7 +468,7 @@ COMPAT_SYSCALL_DEFINE3(s390_write, unsigned int, fd, const char __user *, buf, c if ((compat_ssize_t) count < 0) return -EINVAL; - return sys_write(fd, buf, count); + return ksys_write(fd, buf, count); } /* diff --git a/fs/read_write.c b/fs/read_write.c index f8547b82dfb3..8e8f0b4f52e2 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -578,8 +578,7 @@ SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) return ret; } -SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, - size_t, count) +ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count) { struct fd f = fdget_pos(fd); ssize_t ret = -EBADF; @@ -595,6 +594,12 @@ SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, return ret; } +SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, + size_t, count) +{ + return ksys_write(fd, buf, count); +} + SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, size_t, count, loff_t, pos) { diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 13c7bc43b6ef..c6aa44b6a0a2 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -953,5 +953,6 @@ int ksys_mount(char __user *dev_name, char __user *dir_name, char __user *type, int ksys_umount(char __user *name, int flags); 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); #endif diff --git a/init/do_mounts_rd.c b/init/do_mounts_rd.c index 99e0b649fc0e..2d365c398ccc 100644 --- a/init/do_mounts_rd.c +++ b/init/do_mounts_rd.c @@ -270,7 +270,7 @@ int __init rd_load_image(char *from) printk("Loading disk #%d... ", disk); } sys_read(in_fd, buf, BLOCK_SIZE); - sys_write(out_fd, buf, BLOCK_SIZE); + ksys_write(out_fd, buf, BLOCK_SIZE); #if !defined(CONFIG_S390) if (!(i % 16)) { pr_cont("%c\b", rotator[rotate & 0x3]); @@ -317,7 +317,7 @@ static long __init compr_fill(void *buf, unsigned long len) static long __init compr_flush(void *window, unsigned long outcnt) { - long written = sys_write(crd_outfd, window, outcnt); + long written = ksys_write(crd_outfd, window, outcnt); if (written != outcnt) { if (decompress_error == 0) printk(KERN_ERR diff --git a/init/initramfs.c b/init/initramfs.c index 7e99a0038942..6f972df15bf2 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -27,7 +27,7 @@ static ssize_t __init xwrite(int fd, const char *p, size_t count) /* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */ while (count) { - ssize_t rv = sys_write(fd, p, count); + ssize_t rv = ksys_write(fd, p, count); if (rv < 0) { if (rv == -EINTR || rv == -EAGAIN) -- 2.16.2