Implement SIGEV_THREAD notifications for lio_listio(2)

Our man pages have always indicated that this was supported, but in fact the
feature was never implemented for lio_listio(2).

Reviewed by:	jhb, kib (earlier version)
MFC after:	20 days
Sponsored by:	Spectra Logic Corp
Differential Revision:	https://reviews.freebsd.org/D11680

2 files changed, 40 insertions, 8 deletions

diff --git a/lib/librt/Symbol.map b/lib/librt/Symbol.map
index a4a88b947070..c11b88397afd 100644
--- a/lib/librt/Symbol.map
+++ b/lib/librt/Symbol.map
@@ -26,6 +26,7 @@ FBSD_1.0 {
 };
 
 FBSD_1.5 {
+	lio_listio;
 	mq_getfd_np;
 	timer_oshandle_np;
 };
diff --git a/lib/librt/aio.c b/lib/librt/aio.c
index af88cf3affdd..fd26a9f68e53 100644
--- a/lib/librt/aio.c
+++ b/lib/librt/aio.c
@@ -44,6 +44,7 @@ __weak_reference(__aio_write, aio_write);
 __weak_reference(__aio_return, aio_return);
 __weak_reference(__aio_waitcomplete, aio_waitcomplete);
 __weak_reference(__aio_fsync, aio_fsync);
+__weak_reference(__lio_listio, lio_listio);
 
 typedef void (*aio_func)(union sigval val, struct aiocb *iocb);
 
@@ -53,6 +54,8 @@ extern ssize_t __sys_aio_waitcomplete(struct aiocb **iocbp, struct timespec *tim
 extern ssize_t __sys_aio_return(struct aiocb *iocb);
 extern int __sys_aio_error(struct aiocb *iocb);
 extern int __sys_aio_fsync(int op, struct aiocb *iocb);
+extern int __sys_lio_listio(int mode, struct aiocb * const list[], int nent,
+    struct sigevent *sig);
 
 static void
 aio_dispatch(struct sigev_node *sn)
@@ -63,8 +66,8 @@ aio_dispatch(struct sigev_node *sn)
 }
 
 static int
-aio_sigev_alloc(struct aiocb *iocb, struct sigev_node **sn,
-	struct sigevent *saved_ev)
+aio_sigev_alloc(sigev_id_t id, struct sigevent *sigevent,
+    struct sigev_node **sn, struct sigevent *saved_ev)
 {
 	if (__sigev_check_init()) {
 		/* This might be that thread library is not enabled. */
@@ -72,15 +75,15 @@ aio_sigev_alloc(struct aiocb *iocb, struct sigev_node **sn,
 		return (-1);
 	}
 
-	*sn = __sigev_alloc(SI_ASYNCIO, &iocb->aio_sigevent, NULL, 1);
+	*sn = __sigev_alloc(SI_ASYNCIO, sigevent, NULL, 1);
 	if (*sn == NULL) {
 		errno = EAGAIN;
 		return (-1);
 	}
 	
-	*saved_ev = iocb->aio_sigevent;
-	(*sn)->sn_id = (sigev_id_t)iocb;
-	__sigev_get_sigevent(*sn, &iocb->aio_sigevent, (*sn)->sn_id);
+	*saved_ev = *sigevent;
+	(*sn)->sn_id = id;
+	__sigev_get_sigevent(*sn, sigevent, (*sn)->sn_id);
 	(*sn)->sn_dispatch = aio_dispatch;
 
 	__sigev_list_lock();
@@ -102,7 +105,8 @@ aio_io(struct aiocb *iocb, int (*sysfunc)(struct aiocb *iocb))
 		return (ret);
 	}
 
-	ret = aio_sigev_alloc(iocb, &sn, &saved_ev);
+	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
+			      &saved_ev);
 	if (ret)
 		return (ret);
 	ret = sysfunc(iocb);
@@ -183,7 +187,8 @@ __aio_fsync(int op, struct aiocb *iocb)
 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD)
 		return __sys_aio_fsync(op, iocb);
 
-	ret = aio_sigev_alloc(iocb, &sn, &saved_ev);
+	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
+			      &saved_ev);
 	if (ret)
 		return (ret);
 	ret = __sys_aio_fsync(op, iocb);
@@ -197,3 +202,29 @@ __aio_fsync(int op, struct aiocb *iocb)
 	}
 	return (ret);
 }
+
+int
+__lio_listio(int mode, struct aiocb * const list[], int nent,
+    struct sigevent *sig)
+{
+	struct sigev_node *sn;
+	struct sigevent saved_ev;
+	int ret, err;
+
+	if (sig == NULL || sig->sigev_notify != SIGEV_THREAD)
+		return (__sys_lio_listio(mode, list, nent, sig));
+
+	ret = aio_sigev_alloc((sigev_id_t)list, sig, &sn, &saved_ev);
+	if (ret)
+		return (ret);
+	ret = __sys_lio_listio(mode, list, nent, sig);
+	*sig = saved_ev;
+	if (ret != 0) {
+		err = errno;
+		__sigev_list_lock();
+		__sigev_delete_node(sn);
+		__sigev_list_unlock();
+		errno = err;
+	}
+	return (ret);
+}