[V11 PATCH 08/21] PVH xen: introduce pvh_vcpu_boot_set_info() and vmx_pvh_vcpu_boot_set_info()

[Mukesh Rathor <mukesh.rathor@oracle.com>]

vmx_pvh_vcpu_boot_set_info() is added to a new file pvh.c, to which
more changes are added later, like pvh vmexit handler.

Changes in V11:
   - vmx_pvh_vcpu_boot_set_info pretty much redone to be minimal.

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Acked-by: Keir Fraser <keir@xen.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
PV-HVM-Regression-Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
 xen/arch/x86/hvm/vmx/Makefile     |    1 +
 xen/arch/x86/hvm/vmx/pvh.c        |   54 +++++++++++++++++++++++++++++++++++++
 xen/arch/x86/hvm/vmx/vmx.c        |    1 +
 xen/include/asm-x86/hvm/hvm.h     |    9 ++++++
 xen/include/asm-x86/hvm/vmx/vmx.h |    2 +
 xen/include/public/arch-x86/xen.h |    4 +++
 6 files changed, 71 insertions(+), 0 deletions(-)
 create mode 100644 xen/arch/x86/hvm/vmx/pvh.c

diff --git a/xen/arch/x86/hvm/vmx/Makefile b/xen/arch/x86/hvm/vmx/Makefile
index 373b3d9..59fb5d4 100644
--- a/xen/arch/x86/hvm/vmx/Makefile
+++ b/xen/arch/x86/hvm/vmx/Makefile
@@ -1,5 +1,6 @@
 obj-bin-y += entry.o
 obj-y += intr.o
+obj-y += pvh.o
 obj-y += realmode.o
 obj-y += vmcs.o
 obj-y += vmx.o
diff --git a/xen/arch/x86/hvm/vmx/pvh.c b/xen/arch/x86/hvm/vmx/pvh.c
new file mode 100644
index 0000000..526ce2b
--- /dev/null
+++ b/xen/arch/x86/hvm/vmx/pvh.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2013, Mukesh Rathor, Oracle Corp.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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/hypercall.h>
+#include <xen/guest_access.h>
+#include <asm/p2m.h>
+#include <asm/traps.h>
+#include <asm/hvm/vmx/vmx.h>
+#include <public/sched.h>
+#include <asm/hvm/nestedhvm.h>
+#include <asm/xstate.h>
+
+/*
+ * Set vmcs fields during boot of a vcpu. Called from arch_set_info_guest.
+ *
+ * Boot vcpu call is from tools via:
+ *     do_domctl -> XEN_DOMCTL_setvcpucontext -> arch_set_info_guest
+ *
+ * Secondary vcpu's are brought up by the guest itself via:
+ *     do_vcpu_op -> VCPUOP_initialise -> arch_set_info_guest
+ *     (In case of linux, the call comes from cpu_initialize_context()).
+ *
+ * Note, PVH save/restore is expected to happen the HVM way, ie,
+ *        do_domctl -> XEN_DOMCTL_sethvmcontext -> hvm_load/save
+ * and not get here.
+ *
+ * PVH 32bitfixme: this function needs to be modified for 32bit guest.
+ */
+int vmx_pvh_vcpu_boot_set_info(struct vcpu *v,
+                               struct vcpu_guest_context *ctxtp)
+{
+    if ( ctxtp->ldt_base || ctxtp->ldt_ents ||
+         ctxtp->user_regs.cs || ctxtp->user_regs.ss || ctxtp->user_regs.es ||
+         ctxtp->user_regs.ds || ctxtp->user_regs.fs || ctxtp->user_regs.gs ||
+         *ctxtp->gdt_frames || ctxtp->gdt_ents ||
+         ctxtp->fs_base || ctxtp->gs_base_user )
+        return -EINVAL;
+
+    vmx_vmcs_enter(v);
+    __vmwrite(GUEST_GS_BASE, ctxtp->gs_base_kernel);
+    vmx_vmcs_exit(v);
+
+    return 0;
+}
diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 7292357..a778dca 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -1562,6 +1562,7 @@ static struct hvm_function_table __initdata vmx_function_table = {
     .sync_pir_to_irr      = vmx_sync_pir_to_irr,
     .handle_eoi           = vmx_handle_eoi,
     .nhvm_hap_walk_L1_p2m = nvmx_hap_walk_L1_p2m,
+    .pvh_vcpu_boot_set_info = vmx_pvh_vcpu_boot_set_info,
 };
 
 const struct hvm_function_table * __init start_vmx(void)
diff --git a/xen/include/asm-x86/hvm/hvm.h b/xen/include/asm-x86/hvm/hvm.h
index 00489cf..1bd8fc9 100644
--- a/xen/include/asm-x86/hvm/hvm.h
+++ b/xen/include/asm-x86/hvm/hvm.h
@@ -193,6 +193,9 @@ struct hvm_function_table {
                                 paddr_t *L1_gpa, unsigned int *page_order,
                                 uint8_t *p2m_acc, bool_t access_r,
                                 bool_t access_w, bool_t access_x);
+
+    int (*pvh_vcpu_boot_set_info)(struct vcpu *v,
+                                  struct vcpu_guest_context *ctxtp);
 };
 
 extern struct hvm_function_table hvm_funcs;
@@ -326,6 +329,12 @@ static inline unsigned long hvm_get_shadow_gs_base(struct vcpu *v)
     return hvm_funcs.get_shadow_gs_base(v);
 }
 
+static inline int pvh_vcpu_boot_set_info(struct vcpu *v,
+                                         struct vcpu_guest_context *ctxtp)
+{
+    return hvm_funcs.pvh_vcpu_boot_set_info(v, ctxtp);
+}
+
 #define is_viridian_domain(_d)                                             \
  (is_hvm_domain(_d) && ((_d)->arch.hvm_domain.params[HVM_PARAM_VIRIDIAN]))
 
diff --git a/xen/include/asm-x86/hvm/vmx/vmx.h b/xen/include/asm-x86/hvm/vmx/vmx.h
index c21a303..3ad2188 100644
--- a/xen/include/asm-x86/hvm/vmx/vmx.h
+++ b/xen/include/asm-x86/hvm/vmx/vmx.h
@@ -473,6 +473,8 @@ void vmx_update_guest_eip(void);
 void vmx_dr_access(unsigned long exit_qualification,
                    struct cpu_user_regs *regs);
 void vmx_fpu_enter(struct vcpu *v);
+int  vmx_pvh_vcpu_boot_set_info(struct vcpu *v,
+                                struct vcpu_guest_context *ctxtp);
 
 int alloc_p2m_hap_data(struct p2m_domain *p2m);
 void free_p2m_hap_data(struct p2m_domain *p2m);
diff --git a/xen/include/public/arch-x86/xen.h b/xen/include/public/arch-x86/xen.h
index b7f6a51..4f12f50 100644
--- a/xen/include/public/arch-x86/xen.h
+++ b/xen/include/public/arch-x86/xen.h
@@ -150,6 +150,10 @@ typedef uint64_t tsc_timestamp_t; /* RDTSC timestamp */
 /*
  * The following is all CPU context. Note that the fpu_ctxt block is filled 
  * in by FXSAVE if the CPU has feature FXSR; otherwise FSAVE is used.
+ *
+ * PVH 64bit: In the vcpu boot path, for vmcs context, only gs_base_kernel
+ *            is honored. Other fields like gdt, ldt, and selectors must be
+ *            zeroed. See vmx_pvh_vcpu_boot_set_info.
  */
 struct vcpu_guest_context {
     /* FPU registers come first so they can be aligned for FXSAVE/FXRSTOR. */
-- 
1.7.2.3