aboutsummaryrefslogtreecommitdiff
path: root/fs/eventfd.c
diff options
context:
space:
mode:
authorUlrich Drepper <drepper@redhat.com>2008-07-23 21:29:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-24 10:47:27 -0700
commitb087498eb5605673b0f260a7620d91818cd72304 (patch)
tree977d9dbcd326a9582dfc5ad000995d26886c872e /fs/eventfd.c
parent9deb27baedb79759c3ab9435a7d8b841842d56e9 (diff)
downloadlinux-b087498eb5605673b0f260a7620d91818cd72304.tar.gz
flag parameters: eventfd
This patch adds the new eventfd2 syscall. It extends the old eventfd syscall by one parameter which is meant to hold a flag value. In this patch the only flag support is EFD_CLOEXEC which causes the close-on-exec flag for the returned file descriptor to be set. A new name EFD_CLOEXEC is introduced which in this implementation must have the same value as O_CLOEXEC. The following test must be adjusted for architectures other than x86 and x86-64 and in case the syscall numbers changed. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #include <fcntl.h> #include <stdio.h> #include <unistd.h> #include <sys/syscall.h> #ifndef __NR_eventfd2 # ifdef __x86_64__ # define __NR_eventfd2 290 # elif defined __i386__ # define __NR_eventfd2 328 # else # error "need __NR_eventfd2" # endif #endif #define EFD_CLOEXEC O_CLOEXEC int main (void) { int fd = syscall (__NR_eventfd2, 1, 0); if (fd == -1) { puts ("eventfd2(0) failed"); return 1; } int coe = fcntl (fd, F_GETFD); if (coe == -1) { puts ("fcntl failed"); return 1; } if (coe & FD_CLOEXEC) { puts ("eventfd2(0) sets close-on-exec flag"); return 1; } close (fd); fd = syscall (__NR_eventfd2, 1, EFD_CLOEXEC); if (fd == -1) { puts ("eventfd2(EFD_CLOEXEC) failed"); return 1; } coe = fcntl (fd, F_GETFD); if (coe == -1) { puts ("fcntl failed"); return 1; } if ((coe & FD_CLOEXEC) == 0) { puts ("eventfd2(EFD_CLOEXEC) does not set close-on-exec flag"); return 1; } close (fd); puts ("OK"); return 0; } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [akpm@linux-foundation.org: add sys_ni stub] Signed-off-by: Ulrich Drepper <drepper@redhat.com> Acked-by: Davide Libenzi <davidel@xmailserver.org> Cc: Michael Kerrisk <mtk.manpages@googlemail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/eventfd.c')
-rw-r--r--fs/eventfd.c13
1 files changed, 11 insertions, 2 deletions
diff --git a/fs/eventfd.c b/fs/eventfd.c
index 6094265ca40..bd420e6478a 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -198,11 +198,14 @@ struct file *eventfd_fget(int fd)
return file;
}
-asmlinkage long sys_eventfd(unsigned int count)
+asmlinkage long sys_eventfd2(unsigned int count, int flags)
{
int fd;
struct eventfd_ctx *ctx;
+ if (flags & ~EFD_CLOEXEC)
+ return -EINVAL;
+
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
@@ -214,9 +217,15 @@ asmlinkage long sys_eventfd(unsigned int count)
* When we call this, the initialization must be complete, since
* anon_inode_getfd() will install the fd.
*/
- fd = anon_inode_getfd("[eventfd]", &eventfd_fops, ctx, 0);
+ fd = anon_inode_getfd("[eventfd]", &eventfd_fops, ctx,
+ flags & O_CLOEXEC);
if (fd < 0)
kfree(ctx);
return fd;
}
+asmlinkage long sys_eventfd(unsigned int count)
+{
+ return sys_eventfd2(count, 0);
+}
+