aio: implement io_pgetevents
This is the io_getevents equivalent of ppoll/pselect and allows to
properly mix signals and aio completions (especially with IOCB_CMD_POLL)
and atomically executes the following sequence:
sigset_t origmask;
pthread_sigmask(SIG_SETMASK, &sigmask, &origmask);
ret = io_getevents(ctx, min_nr, nr, events, timeout);
pthread_sigmask(SIG_SETMASK, &origmask, NULL);
Note that unlike many other signal related calls we do not pass a sigmask
size, as that would get us to 7 arguments, which aren't easily supported
by the syscall infrastructure. It seems a lot less painful to just add a
new syscall variant in the unlikely case we're going to increase the
sigset size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 081281a..ad19205 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -330,6 +330,7 @@ extern int put_compat_rusage(const struct rusage *,
struct compat_rusage __user *);
struct compat_siginfo;
+struct __compat_aio_sigset;
struct compat_dirent {
u32 d_ino;
@@ -553,6 +554,12 @@ asmlinkage long compat_sys_io_getevents(compat_aio_context_t ctx_id,
compat_long_t nr,
struct io_event __user *events,
struct compat_timespec __user *timeout);
+asmlinkage long compat_sys_io_pgetevents(compat_aio_context_t ctx_id,
+ compat_long_t min_nr,
+ compat_long_t nr,
+ struct io_event __user *events,
+ struct compat_timespec __user *timeout,
+ const struct __compat_aio_sigset __user *usig);
/* fs/cookies.c */
asmlinkage long compat_sys_lookup_dcookie(u32, u32, char __user *, compat_size_t);
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 70fcda1..811172f 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -290,6 +290,12 @@ asmlinkage long sys_io_getevents(aio_context_t ctx_id,
long nr,
struct io_event __user *events,
struct timespec __user *timeout);
+asmlinkage long sys_io_pgetevents(aio_context_t ctx_id,
+ long min_nr,
+ long nr,
+ struct io_event __user *events,
+ struct timespec __user *timeout,
+ const struct __aio_sigset *sig);
/* fs/xattr.c */
asmlinkage long sys_setxattr(const char __user *path, const char __user *name,