[PATCH 09/23] PVH xen: introduce pvh_set_vcpu_info() and vmx_pvh_set_vcpu_info()

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

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

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
---
 xen/arch/x86/hvm/vmx/Makefile     |    1 +
 xen/arch/x86/hvm/vmx/pvh.c        |   78 +++++++++++++++++++++++++++++++++++++
 xen/arch/x86/hvm/vmx/vmx.c        |    1 +
 xen/include/asm-x86/hvm/hvm.h     |    8 ++++
 xen/include/asm-x86/hvm/vmx/vmx.h |    1 +
 5 files changed, 89 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..b37e423
--- /dev/null
+++ b/xen/arch/x86/hvm/vmx/pvh.c
@@ -0,0 +1,78 @@
+/*
+ * 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 in support of vcpu_op -> VCPUOP_initialise hcall.  Called
+ * from arch_set_info_guest() which sets the (PVH relevant) non-vmcs fields.
+ *
+ * In case of linux:
+ *     The boot vcpu calls this to set some context for the non boot smp vcpu.
+ *     The call comes from cpu_initialize_context().  (boot vcpu 0 context is
+ *     set by the tools via do_domctl -> vcpu_initialise).
+ *
+ * NOTE: In case of VMCS, loading a selector doesn't cause the hidden fields
+ *       to be automatically loaded. We load selectors here but not the hidden
+ *       parts, except for GS_BASE and FS_BASE. This means we require the
+ *       guest to have same hidden values as the default values loaded in the
+ *       vmcs in pvh_construct_vmcs(), ie, the GDT the vcpu is coming up on
+ *       should be something like following,
+ *       (from 64bit linux, CS:0x10 DS/SS:0x18) :
+ *
+ *           ffff88007f704000:  0000000000000000 00cf9b000000ffff
+ *           ffff88007f704010:  00af9b000000ffff 00cf93000000ffff
+ *           ffff88007f704020:  00cffb000000ffff 00cff3000000ffff
+ *
+ */
+int vmx_pvh_set_vcpu_info(struct vcpu *v, struct vcpu_guest_context *ctxtp)
+{
+    if ( v->vcpu_id == 0 )
+        return 0;
+
+    if ( !(ctxtp->flags & VGCF_in_kernel) )
+        return -EINVAL;
+
+    vmx_vmcs_enter(v);
+    __vmwrite(GUEST_GDTR_BASE, ctxtp->gdt.pvh.addr);
+    __vmwrite(GUEST_GDTR_LIMIT, ctxtp->gdt.pvh.limit);
+    __vmwrite(GUEST_LDTR_BASE, ctxtp->ldt_base);
+    __vmwrite(GUEST_LDTR_LIMIT, ctxtp->ldt_ents);
+
+    __vmwrite(GUEST_FS_BASE, ctxtp->fs_base);
+    __vmwrite(GUEST_GS_BASE, ctxtp->gs_base_kernel);
+
+    __vmwrite(GUEST_CS_SELECTOR, ctxtp->user_regs.cs);
+    __vmwrite(GUEST_SS_SELECTOR, ctxtp->user_regs.ss);
+    __vmwrite(GUEST_ES_SELECTOR, ctxtp->user_regs.es);
+    __vmwrite(GUEST_DS_SELECTOR, ctxtp->user_regs.ds);
+    __vmwrite(GUEST_FS_SELECTOR, ctxtp->user_regs.fs);
+    __vmwrite(GUEST_GS_SELECTOR, ctxtp->user_regs.gs);
+
+    if ( vmx_add_guest_msr(MSR_SHADOW_GS_BASE) )
+    {
+        vmx_vmcs_exit(v);
+        return -EINVAL;
+    }
+    vmx_write_guest_msr(MSR_SHADOW_GS_BASE, ctxtp->gs_base_user);
+
+    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..e3c7515 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_set_vcpu_info    = vmx_pvh_set_vcpu_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..072a2a7 100644
--- a/xen/include/asm-x86/hvm/hvm.h
+++ b/xen/include/asm-x86/hvm/hvm.h
@@ -193,6 +193,8 @@ 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_set_vcpu_info)(struct vcpu *v, struct vcpu_guest_context *ctxtp);
 };
 
 extern struct hvm_function_table hvm_funcs;
@@ -326,6 +328,12 @@ static inline unsigned long hvm_get_shadow_gs_base(struct vcpu *v)
     return hvm_funcs.get_shadow_gs_base(v);
 }
 
+static inline int pvh_set_vcpu_info(struct vcpu *v,
+                                    struct vcpu_guest_context *ctxtp)
+{
+    return hvm_funcs.pvh_set_vcpu_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..9e6c481 100644
--- a/xen/include/asm-x86/hvm/vmx/vmx.h
+++ b/xen/include/asm-x86/hvm/vmx/vmx.h
@@ -473,6 +473,7 @@ 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_set_vcpu_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);
-- 
1.7.2.3