On 1/20/21 1:25 PM, Claudio Imbrenda wrote:
On Tue, 19 Jan 2021 20:52:23 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
To centralize the memory allocation for I/O we define
the alloc_io_page/free_io_page functions which share the I/O
memory with the host in case the guest runs with
protected virtualization.
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
lib/s390x/malloc_io.c | 50
+++++++++++++++++++++++++++++++++++++++++++ lib/s390x/malloc_io.h |
18 ++++++++++++++++ s390x/Makefile | 1 +
3 files changed, 69 insertions(+)
create mode 100644 lib/s390x/malloc_io.c
create mode 100644 lib/s390x/malloc_io.h
diff --git a/lib/s390x/malloc_io.c b/lib/s390x/malloc_io.c
new file mode 100644
index 0000000..2a946e0
--- /dev/null
+++ b/lib/s390x/malloc_io.c
@@ -0,0 +1,50 @@
+/*
+ * I/O page allocation
+ *
+ * Copyright (c) 2021 IBM Corp
+ *
+ * Authors:
+ * Pierre Morel <pmorel@xxxxxxxxxxxxx>
+ *
+ * This code is free software; you can redistribute it and/or modify
it
+ * under the terms of the GNU General Public License version 2.
+ *
+ * Using this interface provide host access to the allocated pages in
+ * case the guest is a secure guest.
+ * This is needed for I/O buffers.
+ *
+ */
+#include <libcflat.h>
+#include <asm/page.h>
+#include <asm/uv.h>
+#include <malloc_io.h>
+#include <alloc_page.h>
+#include <asm/facility.h>
+
+void *alloc_io_page(int size)
+{
+ void *p;
+
+ assert(size <= PAGE_SIZE);
I agree with Thomas here, remove size, or use it as a page count or
page order.
+ p = alloc_pages_flags(1, AREA_DMA31);
you are allocating 2 pages here...
humm, yes, forgot to change this as I changed to your interface.
Thanks for the reviewing,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
