On 04.08.20 14:23, Paul Durrant wrote:
diff --git a/xen/include/xen/hvm/ioreq.h b/xen/include/xen/hvm/ioreq.h
new file mode 100644
index 0000000..40b7b5e
--- /dev/null
+++ b/xen/include/xen/hvm/ioreq.h
@@ -0,0 +1,89 @@
+/*
+ * hvm.h: Hardware virtual machine assist interface definitions.
+ *
+ * Copyright (c) 2016 Citrix Systems Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __HVM_IOREQ_H__
+#define __HVM_IOREQ_H__
+
+#include <xen/sched.h>
+
+#include <asm/hvm/ioreq.h>
+
+#define GET_IOREQ_SERVER(d, id) \
+ (d)->arch.hvm.ioreq_server.server[id]
+
+static inline struct hvm_ioreq_server *get_ioreq_server(const struct domain *d,
+ unsigned int id)
+{
+ if ( id >= MAX_NR_IOREQ_SERVERS )
+ return NULL;
+
+ return GET_IOREQ_SERVER(d, id);
+}
+
+static inline bool hvm_ioreq_needs_completion(const ioreq_t *ioreq)
+{
+ return ioreq->state == STATE_IOREQ_READY &&
+ !ioreq->data_is_ptr &&
+ (ioreq->type != IOREQ_TYPE_PIO || ioreq->dir != IOREQ_WRITE);
+}
I don't think having this in common code is correct. The short-cut of not
completing PIO reads seems
somewhat x86 specific. Does ARM even have the concept of PIO?
I am not 100% sure here, but it seems that doesn't have.
Shall I make hvm_ioreq_needs_completion() per arch? Arm variant would
have the same implementation, but without "ioreq->type !=
IOREQ_TYPE_PIO" check...
With your series applied, does any common code actually call
hvm_ioreq_needs_completion()? I suspect it will remain x86 specific, without
any need for an Arm variant.
Yes, it does. Please see common usage in hvm_io_assist() and
handle_hvm_io_completion() (current patch) and usage in Arm code
(arch/arm/io.c: io_state try_fwd_ioserv) [1]
[1]
https://lists.xenproject.org/archives/html/xen-devel/2020-08/msg00072.html
--
Regards,
Oleksandr Tyshchenko
