From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758516AbYEEDru (ORCPT ); Sun, 4 May 2008 23:47:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757178AbYEEDnj (ORCPT ); Sun, 4 May 2008 23:43:39 -0400 Received: from mx1.redhat.com ([66.187.233.31]:52521 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756902AbYEEDnY (ORCPT ); Sun, 4 May 2008 23:43:24 -0400 Date: Sun, 4 May 2008 23:42:46 -0400 From: Ulrich Drepper Message-Id: <200805050342.m453gkOX029832@devserv.devel.redhat.com> To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 07/18] flag parameters: timerfd_create Cc: akpm@linux-foundation.org, davidel@xmailserver.org, mtk.manpages@gmail.com, torvalds@linux-foundation.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The timerfd_create syscall already has a flags parameter. It just is unused so far. This patch changes this by introducing the TFD_CLOEXEC flag to set the close-on-exec flag for the returned file descriptor. A new flag TFD_CLOEXEC is used instead of reusing O_CLOEXEC to prevent exhaustion of the int bit field in case we need more flags. The following test must be adjusted for architectures other than x86 and x86-64 and in case the syscall numbers changed. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #include #include #include #include #include #ifndef __NR_timerfd_create # ifdef __x86_64__ # define __NR_timerfd_create 283 # elif defined __i386__ # define __NR_timerfd_create 322 # else # error "need __NR_timerfd_create" # endif #endif #define TFD_CLOEXEC (1 << 0) int main (void) { int fd = syscall (__NR_timerfd_create, CLOCK_REALTIME, 0); if (fd == -1) { puts ("timerfd_create(0) failed"); return 1; } int coe = fcntl (fd, F_GETFD); if (coe == -1) { puts ("fcntl failed"); return 1; } if (coe & FD_CLOEXEC) { puts ("timerfd_create(0) set close-on-exec flag"); return 1; } close (fd); fd = syscall (__NR_timerfd_create, CLOCK_REALTIME, TFD_CLOEXEC); if (fd == -1) { puts ("timerfd_create(TFD_CLOEXEC) failed"); return 1; } coe = fcntl (fd, F_GETFD); if (coe == -1) { puts ("fcntl failed"); return 1; } if ((coe & FD_CLOEXEC) == 0) { puts ("timerfd_create(TFD_CLOEXEC) set close-on-exec flag"); return 1; } close (fd); puts ("OK"); return 0; } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/timerfd.c | 12 ++++++++++-- include/linux/timerfd.h | 4 +++- 2 files changed, 13 insertions(+), 3 deletions(-) Signed-off-by: Ulrich Drepper diff --git a/fs/timerfd.c b/fs/timerfd.c index d87d354..f998991 100644 --- a/fs/timerfd.c +++ b/fs/timerfd.c @@ -21,6 +21,7 @@ #include #include #include +#include struct timerfd_ctx { struct hrtimer tmr; @@ -179,12 +180,19 @@ static struct file *timerfd_fget(int fd) return file; } +static const struct flags_rmap timerfd_file_flags_remap[] = { + { TFD_CLOEXEC, O_CLOEXEC }, +}; + asmlinkage long sys_timerfd_create(int clockid, int flags) { int ufd; struct timerfd_ctx *ctx; + int fflags; - if (flags) + if (flags_remap(timerfd_file_flags_remap, + ARRAY_SIZE(timerfd_file_flags_remap), + flags, &fflags)) return -EINVAL; if (clockid != CLOCK_MONOTONIC && clockid != CLOCK_REALTIME) @@ -198,7 +207,7 @@ asmlinkage long sys_timerfd_create(int clockid, int flags) ctx->clockid = clockid; hrtimer_init(&ctx->tmr, clockid, HRTIMER_MODE_ABS); - ufd = anon_inode_getfd("[timerfd]", &timerfd_fops, ctx, 0); + ufd = anon_inode_getfd("[timerfd]", &timerfd_fops, ctx, fflags); if (ufd < 0) kfree(ctx); diff --git a/include/linux/timerfd.h b/include/linux/timerfd.h index cf2b10d..c2fb04e 100644 --- a/include/linux/timerfd.h +++ b/include/linux/timerfd.h @@ -8,9 +8,11 @@ #ifndef _LINUX_TIMERFD_H #define _LINUX_TIMERFD_H - +/* Flags for timerfd_settime. */ #define TFD_TIMER_ABSTIME (1 << 0) +/* Flags for timerfd_create. */ +#define TFD_CLOEXEC (1 << 0) #endif /* _LINUX_TIMERFD_H */