diff mbox series

[kvm-unit-tests,v2,2/4] s390x: pv: implement routine to share/unshare memory

Message ID 1601303017-8176-3-git-send-email-pmorel@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x: css: pv: css test adaptation for PV | expand

Commit Message

Pierre Morel Sept. 28, 2020, 2:23 p.m. UTC
When communicating with the host we need to share part of
the memory.

Let's implement the ultravisor calls for this.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Suggested-by: Janosch Frank <frankja@linux.ibm.com>
---
 lib/s390x/asm/uv.h | 50 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

Comments

Cornelia Huck Sept. 29, 2020, 10:51 a.m. UTC | #1
On Mon, 28 Sep 2020 16:23:35 +0200
Pierre Morel <pmorel@linux.ibm.com> wrote:

> When communicating with the host we need to share part of
> the memory.
> 
> Let's implement the ultravisor calls for this.
> 
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> Suggested-by: Janosch Frank <frankja@linux.ibm.com>
> ---
>  lib/s390x/asm/uv.h | 50 ++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 50 insertions(+)

Acked-by: Cornelia Huck <cohuck@redhat.com>
diff mbox series

Patch

diff --git a/lib/s390x/asm/uv.h b/lib/s390x/asm/uv.h
index 4c2fc48..f7690a2 100644
--- a/lib/s390x/asm/uv.h
+++ b/lib/s390x/asm/uv.h
@@ -71,4 +71,54 @@  static inline int uv_call(unsigned long r1, unsigned long r2)
 	return cc;
 }
 
+static inline int share(unsigned long addr, u16 cmd)
+{
+	struct uv_cb_share uvcb = {
+		.header.cmd = cmd,
+		.header.len = sizeof(uvcb),
+		.paddr = addr
+	};
+	int cc;
+
+	cc = uv_call(0, (u64)&uvcb);
+	if (!cc && (uvcb.header.rc == 0x0001))
+		return 0;
+
+	report(0, "cc %d response code: %04x", cc, uvcb.header.rc);
+	return -1;
+}
+
+/*
+ * Guest 2 request to the Ultravisor to make a page shared with the
+ * hypervisor for IO.
+ *
+ * @addr: Real or absolute address of the page to be shared
+ */
+static inline int uv_set_shared(unsigned long addr)
+{
+	int ret;
+
+	report_prefix_push("PV Set Shared access");
+	ret = share(addr, UVC_CMD_SET_SHARED_ACCESS);
+	report_prefix_pop();
+
+	return ret;
+}
+
+/*
+ * Guest 2 request to the Ultravisor to make a page unshared.
+ *
+ * @addr: Real or absolute address of the page to be unshared
+ */
+static inline int uv_remove_shared(unsigned long addr)
+{
+	int ret;
+
+	report_prefix_push("PV Remove Shared access");
+	ret = share(addr, UVC_CMD_REMOVE_SHARED_ACCESS);
+	report_prefix_pop();
+
+	return ret;
+}
+
 #endif