[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] [PATCH v12 1/9] x86: add generic resource (e.g. MSR) access hypercall



Add a generic resource access hypercall for tool stack or other
components, e.g., accessing MSR, port I/O, etc.

Signed-off-by: Dongxiao Xu <dongxiao.xu@xxxxxxxxx>
---
 xen/arch/x86/Makefile             |    1 +
 xen/arch/x86/platform_hypercall.c |   39 ++++++++++++
 xen/arch/x86/resource.c           |  119 +++++++++++++++++++++++++++++++++++++
 xen/include/asm-x86/resource.h    |   40 +++++++++++++
 xen/include/public/platform.h     |   24 ++++++++
 xen/include/xlat.lst              |    1 +
 6 files changed, 224 insertions(+)
 create mode 100644 xen/arch/x86/resource.c
 create mode 100644 xen/include/asm-x86/resource.h

diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 6c90b1b..e0cee24 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -59,6 +59,7 @@ obj-y += crash.o
 obj-y += tboot.o
 obj-y += hpet.o
 obj-y += xstate.o
+obj-y += resource.o
 
 obj-$(crash_debug) += gdbstub.o
 
diff --git a/xen/arch/x86/platform_hypercall.c 
b/xen/arch/x86/platform_hypercall.c
index 2162811..da3d6c4 100644
--- a/xen/arch/x86/platform_hypercall.c
+++ b/xen/arch/x86/platform_hypercall.c
@@ -32,6 +32,7 @@
 #include <asm/setup.h>
 #include "cpu/mtrr/mtrr.h"
 #include <xsm/xsm.h>
+#include <asm/resource.h>
 
 #ifndef COMPAT
 typedef long ret_t;
@@ -601,6 +602,44 @@ ret_t 
do_platform_op(XEN_GUEST_HANDLE_PARAM(xen_platform_op_t) u_xenpf_op)
     }
     break;
 
+    case XENPF_resource_op:
+    {
+        struct xen_resource_access info;
+
+        info.nr = op->u.resource_op.nr;
+        info.type = op->u.resource_op.type;
+        info.data = xmalloc_array(xenpf_resource_data_t, info.nr);
+        if ( !info.data )
+        {
+            ret = -ENOMEM;
+            break;
+        }
+
+        if ( copy_from_guest(info.data, op->u.resource_op.data, info.nr) )
+        {
+            xfree(info.data);
+            ret = -EFAULT;
+            break;
+        }
+
+        ret = resource_access_helper(&info);
+        if ( ret )
+        {
+            xfree(info.data);
+            break;
+        }
+
+        if ( copy_to_guest(op->u.resource_op.data, info.data, info.nr) )
+        {
+            xfree(info.data);
+            ret = -EFAULT;
+            break;
+        }
+
+        xfree(info.data);
+    }
+    break;
+
     default:
         ret = -ENOSYS;
         break;
diff --git a/xen/arch/x86/resource.c b/xen/arch/x86/resource.c
new file mode 100644
index 0000000..cc548cd
--- /dev/null
+++ b/xen/arch/x86/resource.c
@@ -0,0 +1,119 @@
+/*
+ * resource.c: Helpers for Dom0 to access system resource
+ *
+ * Copyright (c) 2014, Intel Corporation
+ * Author: Dongxiao Xu <dongxiao.xu@xxxxxxxxx>
+ *
+ * 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.
+ */
+
+#include <xen/types.h>
+#include <xen/domain.h>
+#include <xen/guest_access.h>
+#include <public/platform.h>
+#include <asm/msr.h>
+#include <asm/event.h>
+#include <asm/resource.h>
+
+static int resource_access_one(uint32_t type, uint32_t cmd,
+                                uint64_t idx, uint64_t *val)
+{
+    int ret = 0;
+
+    switch ( type )
+    {
+    case XEN_RESOURCE_TYPE_MSR:
+        if ( cmd == XEN_RESOURCE_OP_READ )
+            ret = rdmsr_safe(idx, *val);
+        else if ( cmd == XEN_RESOURCE_OP_WRITE )
+            ret = wrmsr_safe(idx, *val);
+        break;
+
+    default:
+        gdprintk(XENLOG_WARNING, "unsupported resource type: %d\n", type);
+        ret = -ENOSYS;
+        break;
+    }
+
+    return ret;
+}
+
+static void resource_access_multi(void *param)
+{
+    struct xen_resource_access *info = param;
+    unsigned int i;
+    int ret = 0;
+
+    for ( i = 0; i < info->nr; i++ )
+    {
+        if ( !is_idle_vcpu(current) && hypercall_preempt_check() )
+        {
+            ret = -ERESTART;
+            break;
+        }
+        ret = resource_access_one(info->type, info->data[i].cmd,
+                                  info->data[i].idx, &info->data[i].val);
+        if ( ret )
+            break;
+    }
+
+    info->ret = ret;
+}
+
+int resource_access_helper(struct xen_resource_access *info)
+{
+    struct xen_resource_access iter;
+    unsigned int i, last_cpu = ~0;
+
+    iter.ret = 0;
+    iter.nr = 0;
+    iter.type = info->type;
+    iter.data = info->data;
+
+    for ( i = 0; i < info->nr; i++ )
+    {
+        if ( iter.nr && info->data[i].cpu != last_cpu )
+        {
+            if ( last_cpu == smp_processor_id() )
+                resource_access_multi(&iter);
+            else
+                /* Set wait=1 to ensure the access order  */
+                on_selected_cpus(cpumask_of(last_cpu),
+                                 resource_access_multi, &iter, 1);
+
+            if ( iter.ret )
+                return iter.ret;
+
+            iter.nr = 0;
+            iter.data = &info->data[i];
+        }
+
+        last_cpu = info->data[i].cpu;
+        iter.nr++;
+    }
+
+    if ( last_cpu == smp_processor_id() )
+        resource_access_multi(&iter);
+    else
+        on_selected_cpus(cpumask_of(last_cpu),
+                         resource_access_multi, &iter, 1);
+
+    return iter.ret;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/include/asm-x86/resource.h b/xen/include/asm-x86/resource.h
new file mode 100644
index 0000000..74b46be
--- /dev/null
+++ b/xen/include/asm-x86/resource.h
@@ -0,0 +1,40 @@
+/*
+ * resource.h: Helpers for Dom0 to access system resource
+ *
+ * Copyright (c) 2014, Intel Corporation
+ * Author: Dongxiao Xu <dongxiao.xu@xxxxxxxxx>
+ *
+ * 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.
+ */
+#ifndef __ASM_RESOURCE_H__
+#define __ASM_RESOURCE_H__
+
+#include <public/platform.h>
+
+struct xen_resource_access {
+    int32_t ret;
+    uint32_t nr;
+    uint32_t type;
+    xenpf_resource_data_t *data;
+};
+
+int resource_access_helper(struct xen_resource_access *info);
+
+#endif /* __ASM_RESOURCE_H__ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/include/public/platform.h b/xen/include/public/platform.h
index 053b9fa..eafdc8a 100644
--- a/xen/include/public/platform.h
+++ b/xen/include/public/platform.h
@@ -527,6 +527,29 @@ struct xenpf_core_parking {
 typedef struct xenpf_core_parking xenpf_core_parking_t;
 DEFINE_XEN_GUEST_HANDLE(xenpf_core_parking_t);
 
+#define XENPF_resource_op   61
+
+#define XEN_RESOURCE_OP_READ  0
+#define XEN_RESOURCE_OP_WRITE 1
+
+#define XEN_RESOURCE_TYPE_MSR  0
+
+struct xenpf_resource_data {
+    uint32_t cmd;       /* XEN_RESOURCE_OP_* */
+    uint32_t cpu;
+    uint64_t idx;
+    uint64_t val;
+};
+typedef struct xenpf_resource_data xenpf_resource_data_t;
+DEFINE_XEN_GUEST_HANDLE(xenpf_resource_data_t);
+struct xenpf_resource_op {
+    uint32_t nr;
+    uint32_t type;      /* XEN_RESOURCE_TYPE_* */
+    XEN_GUEST_HANDLE(xenpf_resource_data_t) data;
+};
+typedef struct xenpf_resource_op xenpf_resource_op_t;
+DEFINE_XEN_GUEST_HANDLE(xenpf_resource_op_t);
+
 /*
  * ` enum neg_errnoval
  * ` HYPERVISOR_platform_op(const struct xen_platform_op*);
@@ -553,6 +576,7 @@ struct xen_platform_op {
         struct xenpf_cpu_hotadd        cpu_add;
         struct xenpf_mem_hotadd        mem_add;
         struct xenpf_core_parking      core_parking;
+        struct xenpf_resource_op       resource_op;
         uint8_t                        pad[128];
     } u;
 };
diff --git a/xen/include/xlat.lst b/xen/include/xlat.lst
index 9a35dd7..06ed7b9 100644
--- a/xen/include/xlat.lst
+++ b/xen/include/xlat.lst
@@ -88,6 +88,7 @@
 ?      xenpf_enter_acpi_sleep          platform.h
 ?      xenpf_pcpuinfo                  platform.h
 ?      xenpf_pcpu_version              platform.h
+?      xenpf_resource_op               platform.h
 !      sched_poll                      sched.h
 ?      sched_remote_shutdown           sched.h
 ?      sched_shutdown                  sched.h
-- 
1.7.9.5


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.