From bd911530b732bdffd98f697fd89a7164ea66b622 Mon Sep 17 00:00:00 2001
From: Mahdi Mokhtari <mmokhi@FreeBSD.org>
Date: Fri, 24 Feb 2017 20:04:02 +0000
Subject: [PATCH] Add linux_preadv() and linux_pwritev() syscalls to
 Linuxulator.

Reviewed by:	dchagin
Approved by:	dchagin, trasz (src committers)
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D9722
---
 sys/amd64/linux/linux_dummy.c       |  3 --
 sys/amd64/linux32/linux.h           |  3 ++
 sys/amd64/linux32/linux32_dummy.c   |  3 --
 sys/amd64/linux32/linux32_machdep.c |  2 +-
 sys/compat/linux/linux_file.c       | 56 +++++++++++++++++++++++++++++
 sys/i386/linux/linux_dummy.c        |  3 --
 6 files changed, 60 insertions(+), 10 deletions(-)

diff --git a/sys/amd64/linux/linux_dummy.c b/sys/amd64/linux/linux_dummy.c
index 690205a0e6cc..8045023213ba 100644
--- a/sys/amd64/linux/linux_dummy.c
+++ b/sys/amd64/linux/linux_dummy.c
@@ -110,9 +110,6 @@ DUMMY(timerfd_gettime);
 /* linux 2.6.27: */
 DUMMY(signalfd4);
 DUMMY(inotify_init1);
-/* linux 2.6.30: */
-DUMMY(preadv);
-DUMMY(pwritev);
 /* linux 2.6.31: */
 DUMMY(perf_event_open);
 /* linux 2.6.38: */
diff --git a/sys/amd64/linux32/linux.h b/sys/amd64/linux32/linux.h
index 97da878339c0..687f8e890a29 100644
--- a/sys/amd64/linux32/linux.h
+++ b/sys/amd64/linux32/linux.h
@@ -663,6 +663,7 @@ struct l_user_desc {
 	(((desc)->b >> LINUX_ENTRY_B_USEABLE) & 1)
 
 struct iovec;
+struct uio;
 
 struct l_iovec32 {
 	uint32_t	iov_base;
@@ -671,6 +672,8 @@ struct l_iovec32 {
 
 int linux32_copyiniov(struct l_iovec32 *iovp32, l_ulong iovcnt,
 			    struct iovec **iovp, int error);
+int linux32_copyinuio(struct l_iovec32 *iovp, l_ulong iovcnt,
+			    struct uio **uiop);
 int linux_copyout_rusage(struct rusage *ru, void *uaddr);
 
 /* robust futexes */
diff --git a/sys/amd64/linux32/linux32_dummy.c b/sys/amd64/linux32/linux32_dummy.c
index 9ba578c47e0e..8a59859c36f1 100644
--- a/sys/amd64/linux32/linux32_dummy.c
+++ b/sys/amd64/linux32/linux32_dummy.c
@@ -110,9 +110,6 @@ DUMMY(timerfd_gettime);
 /* linux 2.6.27: */
 DUMMY(signalfd4);
 DUMMY(inotify_init1);
-/* linux 2.6.30: */
-DUMMY(preadv);
-DUMMY(pwritev);
 /* linux 2.6.31: */
 DUMMY(perf_event_open);
 /* linux 2.6.33: */
diff --git a/sys/amd64/linux32/linux32_machdep.c b/sys/amd64/linux32/linux32_machdep.c
index 5b66d2f90fdf..dd741e603bec 100644
--- a/sys/amd64/linux32/linux32_machdep.c
+++ b/sys/amd64/linux32/linux32_machdep.c
@@ -144,7 +144,7 @@ linux_execve(struct thread *td, struct linux_execve_args *args)
 
 CTASSERT(sizeof(struct l_iovec32) == 8);
 
-static int
+int
 linux32_copyinuio(struct l_iovec32 *iovp, l_ulong iovcnt, struct uio **uiop)
 {
 	struct l_iovec32 iov32;
diff --git a/sys/compat/linux/linux_file.c b/sys/compat/linux/linux_file.c
index a7695f010cee..37b8595ea345 100644
--- a/sys/compat/linux/linux_file.c
+++ b/sys/compat/linux/linux_file.c
@@ -1027,6 +1027,62 @@ linux_pwrite(struct thread *td, struct linux_pwrite_args *uap)
 	return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte, uap->offset));
 }
 
+int
+linux_preadv(struct thread *td, struct linux_preadv_args *uap)
+{
+	struct uio *auio;
+	int error;
+	off_t offset;
+
+	/*
+	 * According http://man7.org/linux/man-pages/man2/preadv.2.html#NOTES
+	 * pos_l and pos_h, respectively, contain the
+	 * low order and high order 32 bits of offset.
+	 */
+	offset = (((off_t)uap->pos_h << (sizeof(offset) * 4)) <<
+	    (sizeof(offset) * 4)) | uap->pos_l;
+	if (offset < 0)
+		return (EINVAL);
+#ifdef COMPAT_LINUX32
+	error = linux32_copyinuio(PTRIN(uap->vec), uap->vlen, &auio);
+#else
+	error = copyinuio(uap->vec, uap->vlen, &auio);
+#endif
+	if (error != 0)
+		return (error);
+	error = kern_preadv(td, uap->fd, auio, offset);
+	free(auio, M_IOV);
+	return (error);
+}
+
+int
+linux_pwritev(struct thread *td, struct linux_pwritev_args *uap)
+{
+	struct uio *auio;
+	int error;
+	off_t offset;
+
+	/*
+	 * According http://man7.org/linux/man-pages/man2/pwritev.2.html#NOTES
+	 * pos_l and pos_h, respectively, contain the
+	 * low order and high order 32 bits of offset.
+	 */
+	offset = (((off_t)uap->pos_h << (sizeof(offset) * 4)) <<
+	    (sizeof(offset) * 4)) | uap->pos_l;
+	if (offset < 0)
+		return (EINVAL);
+#ifdef COMPAT_LINUX32
+	error = linux32_copyinuio(PTRIN(uap->vec), uap->vlen, &auio);
+#else
+	error = copyinuio(uap->vec, uap->vlen, &auio);
+#endif
+	if (error != 0)
+		return (error);
+	error = kern_pwritev(td, uap->fd, auio, offset);
+	free(auio, M_IOV);
+	return (error);
+}
+
 int
 linux_mount(struct thread *td, struct linux_mount_args *args)
 {
diff --git a/sys/i386/linux/linux_dummy.c b/sys/i386/linux/linux_dummy.c
index 65f80c6f10be..06145c0dde53 100644
--- a/sys/i386/linux/linux_dummy.c
+++ b/sys/i386/linux/linux_dummy.c
@@ -106,9 +106,6 @@ DUMMY(timerfd_gettime);
 /* linux 2.6.27: */
 DUMMY(signalfd4);
 DUMMY(inotify_init1);
-/* linux 2.6.30: */
-DUMMY(preadv);
-DUMMY(pwritev);
 /* linux 2.6.31: */
 DUMMY(perf_event_open);
 /* linux 2.6.33: */