From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753335AbeC2LaZ (ORCPT ); Thu, 29 Mar 2018 07:30:25 -0400 Received: from isilmar-4.linta.de ([136.243.71.142]:59868 "EHLO isilmar-4.linta.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752310AbeC2L01 (ORCPT ); Thu, 29 Mar 2018 07:26:27 -0400 From: Dominik Brodowski To: linux-kernel@vger.kernel.org Cc: viro@ZenIV.linux.org.uk, torvalds@linux-foundation.org, arnd@arndb.de, linux-arch@vger.kernel.org, Al Viro , Andrew Morton Subject: [PATCH 094/109] fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls Date: Thu, 29 Mar 2018 13:24:11 +0200 Message-Id: <20180329112426.23043-95-linux@dominikbrodowski.net> X-Mailer: git-send-email 2.16.3 In-Reply-To: <20180329112426.23043-1-linux@dominikbrodowski.net> References: <20180329112426.23043-1-linux@dominikbrodowski.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using the ksys_p{read,write}64() wrappers allows us to get rid of in-kernel calls to the sys_pread64() and sys_pwrite64() syscalls. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_p{read,write}64(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro Cc: Andrew Morton Signed-off-by: Dominik Brodowski --- arch/mips/kernel/linux32.c | 4 ++-- arch/parisc/kernel/sys_parisc.c | 4 ++-- arch/powerpc/kernel/sys_ppc32.c | 4 ++-- arch/s390/kernel/compat_linux.c | 4 ++-- arch/sh/kernel/sys_sh32.c | 4 ++-- arch/sparc/kernel/sys_sparc32.c | 4 ++-- arch/x86/ia32/sys_ia32.c | 8 ++++---- fs/read_write.c | 20 ++++++++++++++++---- include/linux/syscalls.h | 4 ++++ 9 files changed, 36 insertions(+), 20 deletions(-) diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c index 58e7dd27f106..91e85e2f8aa5 100644 --- a/arch/mips/kernel/linux32.c +++ b/arch/mips/kernel/linux32.c @@ -105,13 +105,13 @@ SYSCALL_DEFINE5(32_llseek, unsigned int, fd, unsigned int, offset_high, SYSCALL_DEFINE6(32_pread, unsigned long, fd, char __user *, buf, size_t, count, unsigned long, unused, unsigned long, a4, unsigned long, a5) { - return sys_pread64(fd, buf, count, merge_64(a4, a5)); + return ksys_pread64(fd, buf, count, merge_64(a4, a5)); } SYSCALL_DEFINE6(32_pwrite, unsigned int, fd, const char __user *, buf, size_t, count, u32, unused, u64, a4, u64, a5) { - return sys_pwrite64(fd, buf, count, merge_64(a4, a5)); + return ksys_pwrite64(fd, buf, count, merge_64(a4, a5)); } SYSCALL_DEFINE1(32_personality, unsigned long, personality) diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c index 3377a00163c3..4f47e8379854 100644 --- a/arch/parisc/kernel/sys_parisc.c +++ b/arch/parisc/kernel/sys_parisc.c @@ -333,13 +333,13 @@ asmlinkage long parisc_ftruncate64(unsigned int fd, asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count, unsigned int high, unsigned int low) { - return sys_pread64(fd, buf, count, (loff_t)high << 32 | low); + return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low); } asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf, size_t count, unsigned int high, unsigned int low) { - return sys_pwrite64(fd, buf, count, (loff_t)high << 32 | low); + return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low); } asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low, diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c index a0a251d7c9c5..36a651e6e033 100644 --- a/arch/powerpc/kernel/sys_ppc32.c +++ b/arch/powerpc/kernel/sys_ppc32.c @@ -77,13 +77,13 @@ unsigned long compat_sys_mmap2(unsigned long addr, size_t len, compat_ssize_t compat_sys_pread64(unsigned int fd, char __user *ubuf, compat_size_t count, u32 reg6, u32 poshi, u32 poslo) { - return sys_pread64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo); + return ksys_pread64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo); } compat_ssize_t compat_sys_pwrite64(unsigned int fd, const char __user *ubuf, compat_size_t count, u32 reg6, u32 poshi, u32 poslo) { - return sys_pwrite64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo); + return ksys_pwrite64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo); } compat_ssize_t compat_sys_readahead(int fd, u32 r4, u32 offhi, u32 offlo, u32 count) diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c index e4092ec17ea5..71e2c5bc4926 100644 --- a/arch/s390/kernel/compat_linux.c +++ b/arch/s390/kernel/compat_linux.c @@ -315,7 +315,7 @@ COMPAT_SYSCALL_DEFINE5(s390_pread64, unsigned int, fd, char __user *, ubuf, { if ((compat_ssize_t) count < 0) return -EINVAL; - return sys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low); + return ksys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low); } COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubuf, @@ -323,7 +323,7 @@ COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubu { if ((compat_ssize_t) count < 0) return -EINVAL; - return sys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low); + return ksys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low); } COMPAT_SYSCALL_DEFINE4(s390_readahead, int, fd, u32, high, u32, low, s32, count) diff --git a/arch/sh/kernel/sys_sh32.c b/arch/sh/kernel/sys_sh32.c index f8dc8bfd4606..c37ee3d0c803 100644 --- a/arch/sh/kernel/sys_sh32.c +++ b/arch/sh/kernel/sys_sh32.c @@ -39,13 +39,13 @@ asmlinkage int sys_sh_pipe(void) asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char __user *buf, size_t count, long dummy, loff_t pos) { - return sys_pread64(fd, buf, count, pos); + return ksys_pread64(fd, buf, count, pos); } asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char __user *buf, size_t count, long dummy, loff_t pos) { - return sys_pwrite64(fd, buf, count, pos); + return ksys_pwrite64(fd, buf, count, pos); } asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1, diff --git a/arch/sparc/kernel/sys_sparc32.c b/arch/sparc/kernel/sys_sparc32.c index aab2428b17b5..40c0d2e1db1d 100644 --- a/arch/sparc/kernel/sys_sparc32.c +++ b/arch/sparc/kernel/sys_sparc32.c @@ -200,7 +200,7 @@ asmlinkage compat_ssize_t sys32_pread64(unsigned int fd, unsigned long poshi, unsigned long poslo) { - return sys_pread64(fd, ubuf, count, (poshi << 32) | poslo); + return ksys_pread64(fd, ubuf, count, (poshi << 32) | poslo); } asmlinkage compat_ssize_t sys32_pwrite64(unsigned int fd, @@ -209,7 +209,7 @@ asmlinkage compat_ssize_t sys32_pwrite64(unsigned int fd, unsigned long poshi, unsigned long poslo) { - return sys_pwrite64(fd, ubuf, count, (poshi << 32) | poslo); + return ksys_pwrite64(fd, ubuf, count, (poshi << 32) | poslo); } asmlinkage long compat_sys_readahead(int fd, diff --git a/arch/x86/ia32/sys_ia32.c b/arch/x86/ia32/sys_ia32.c index 90e7a2b3dc5b..c08c25f73d79 100644 --- a/arch/x86/ia32/sys_ia32.c +++ b/arch/x86/ia32/sys_ia32.c @@ -174,15 +174,15 @@ COMPAT_SYSCALL_DEFINE1(x86_mmap, struct mmap_arg_struct32 __user *, arg) COMPAT_SYSCALL_DEFINE5(x86_pread, unsigned int, fd, char __user *, ubuf, u32, count, u32, poslo, u32, poshi) { - return sys_pread64(fd, ubuf, count, - ((loff_t)AA(poshi) << 32) | AA(poslo)); + return ksys_pread64(fd, ubuf, count, + ((loff_t)AA(poshi) << 32) | AA(poslo)); } COMPAT_SYSCALL_DEFINE5(x86_pwrite, unsigned int, fd, const char __user *, ubuf, u32, count, u32, poslo, u32, poshi) { - return sys_pwrite64(fd, ubuf, count, - ((loff_t)AA(poshi) << 32) | AA(poslo)); + return ksys_pwrite64(fd, ubuf, count, + ((loff_t)AA(poshi) << 32) | AA(poslo)); } diff --git a/fs/read_write.c b/fs/read_write.c index fc441e1ac683..c4eabbfc90df 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -610,8 +610,8 @@ SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, return ksys_write(fd, buf, count); } -SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, - size_t, count, loff_t, pos) +ssize_t ksys_pread64(unsigned int fd, char __user *buf, size_t count, + loff_t pos) { struct fd f; ssize_t ret = -EBADF; @@ -630,8 +630,14 @@ SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, return ret; } -SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, - size_t, count, loff_t, pos) +SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, + size_t, count, loff_t, pos) +{ + return ksys_pread64(fd, buf, count, pos); +} + +ssize_t ksys_pwrite64(unsigned int fd, const char __user *buf, + size_t count, loff_t pos) { struct fd f; ssize_t ret = -EBADF; @@ -650,6 +656,12 @@ SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, return ret; } +SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, + size_t, count, loff_t, pos) +{ + return ksys_pwrite64(fd, buf, count, pos); +} + static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, loff_t *ppos, int type, rwf_t flags) { diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 78b79e3a1279..a30e4c2d0c27 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -965,6 +965,10 @@ int ksys_unshare(unsigned long unshare_flags); int ksys_setsid(void); int ksys_sync_file_range(int fd, loff_t offset, loff_t nbytes, unsigned int flags); +ssize_t ksys_pread64(unsigned int fd, char __user *buf, size_t count, + loff_t pos); +ssize_t ksys_pwrite64(unsigned int fd, const char __user *buf, + size_t count, loff_t pos); /* * The following kernel syscall equivalents are just wrappers to fs-internal -- 2.16.3