[PATCH 06/18] PVH xen: Introduce PVH guest type and some basic changes.

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

This patch introduces the concept of a pvh guest. There are other basic
changes like creating macros to check for pv/pvh vcpu/domain, and also
modifying copy-macros to account for pvh. Finally, guest_kernel_mode is
changed to boast that a PVH doesn't need to check for TF_kernel_mode
flag since the kernel runs in ring 0.

Chagnes in V2:
  - make is_pvh/is_hvm enum instead of adding is_pvh as a new flag.
  - fix indentation and spacing in guest_kernel_mode macro.
  - add debug only BUG() in GUEST_KERNEL_RPL macro as it should no longer
    be called in any PVH paths.

Chagnes in V3:
  - Rename enum fields, and add is_pv to it.
  - Get rid if is_hvm_or_pvh_* macros.

Chagnes in V4:
  - Move e820 fields out of pv_domain struct.

Chagnes in V5:
  - Move e820 changes above in V4, to a separate patch.

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
---
 xen/arch/x86/debug.c               |    2 +-
 xen/arch/x86/domain.c              |    7 +++++++
 xen/common/domain.c                |    2 +-
 xen/include/asm-x86/desc.h         |    6 ++++++
 xen/include/asm-x86/guest_access.h |   12 ++++++------
 xen/include/asm-x86/x86_64/regs.h  |    9 +++++----
 xen/include/public/domctl.h        |    3 +++
 xen/include/xen/sched.h            |   21 ++++++++++++++++++---
 8 files changed, 47 insertions(+), 15 deletions(-)

diff --git a/xen/arch/x86/debug.c b/xen/arch/x86/debug.c
index e67473e..167421d 100644
--- a/xen/arch/x86/debug.c
+++ b/xen/arch/x86/debug.c
@@ -158,7 +158,7 @@ dbg_rw_guest_mem(dbgva_t addr, dbgbyte_t *buf, int len, struct domain *dp,
 
         pagecnt = min_t(long, PAGE_SIZE - (addr & ~PAGE_MASK), len);
 
-        mfn = (dp->is_hvm
+        mfn = (!is_pv_domain(dp)
                ? dbg_hvm_va2mfn(addr, dp, toaddr, &gfn)
                : dbg_pv_va2mfn(addr, dp, pgd3));
         if ( mfn == INVALID_MFN ) 
diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 6c85c94..ee90b8a 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -644,6 +644,13 @@ int arch_set_info_guest(
     unsigned int i;
     int rc = 0, compat;
 
+    /* This removed when all patches are checked in and PVH is done. */
+    if ( is_pvh_vcpu(v) )
+    {
+        printk("PVH: You don't have the correct xen version for PVH\n");
+        return -EINVAL;
+    }
+
     /* The context is a compat-mode one if the target domain is compat-mode;
      * we expect the tools to DTRT even in compat-mode callers. */
     compat = is_pv_32on64_domain(d);
diff --git a/xen/common/domain.c b/xen/common/domain.c
index fac3470..6ece3fe 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -236,7 +236,7 @@ struct domain *domain_create(
         goto fail;
 
     if ( domcr_flags & DOMCRF_hvm )
-        d->is_hvm = 1;
+        d->guest_type = is_hvm;
 
     if ( domid == 0 )
     {
diff --git a/xen/include/asm-x86/desc.h b/xen/include/asm-x86/desc.h
index 354b889..4eaa845 100644
--- a/xen/include/asm-x86/desc.h
+++ b/xen/include/asm-x86/desc.h
@@ -38,7 +38,13 @@
 
 #ifndef __ASSEMBLY__
 
+#ifndef NDEBUG
+/* PVH 32bitfixme : see emulate_gate_op call from do_general_protection */
+#define GUEST_KERNEL_RPL(d) (is_pvh_domain(d) ? ({ BUG(); 0; }) :    \
+                                                is_pv_32bit_domain(d) ? 1 : 3)
+#else
 #define GUEST_KERNEL_RPL(d) (is_pv_32bit_domain(d) ? 1 : 3)
+#endif
 
 /* Fix up the RPL of a guest segment selector. */
 #define __fixup_guest_selector(d, sel)                             \
diff --git a/xen/include/asm-x86/guest_access.h b/xen/include/asm-x86/guest_access.h
index ca700c9..675dda1 100644
--- a/xen/include/asm-x86/guest_access.h
+++ b/xen/include/asm-x86/guest_access.h
@@ -14,27 +14,27 @@
 
 /* Raw access functions: no type checking. */
 #define raw_copy_to_guest(dst, src, len)        \
-    (is_hvm_vcpu(current) ?                     \
+    (!is_pv_vcpu(current) ?                     \
      copy_to_user_hvm((dst), (src), (len)) :    \
      copy_to_user((dst), (src), (len)))
 #define raw_copy_from_guest(dst, src, len)      \
-    (is_hvm_vcpu(current) ?                     \
+    (!is_pv_vcpu(current) ?                     \
      copy_from_user_hvm((dst), (src), (len)) :  \
      copy_from_user((dst), (src), (len)))
 #define raw_clear_guest(dst,  len)              \
-    (is_hvm_vcpu(current) ?                     \
+    (!is_pv_vcpu(current) ?                     \
      clear_user_hvm((dst), (len)) :             \
      clear_user((dst), (len)))
 #define __raw_copy_to_guest(dst, src, len)      \
-    (is_hvm_vcpu(current) ?                     \
+    (!is_pv_vcpu(current) ?                     \
      copy_to_user_hvm((dst), (src), (len)) :    \
      __copy_to_user((dst), (src), (len)))
 #define __raw_copy_from_guest(dst, src, len)    \
-    (is_hvm_vcpu(current) ?                     \
+    (!is_pv_vcpu(current) ?                     \
      copy_from_user_hvm((dst), (src), (len)) :  \
      __copy_from_user((dst), (src), (len)))
 #define __raw_clear_guest(dst,  len)            \
-    (is_hvm_vcpu(current) ?                     \
+    (!is_pv_vcpu(current) ?                     \
      clear_user_hvm((dst), (len)) :             \
      clear_user((dst), (len)))
 
diff --git a/xen/include/asm-x86/x86_64/regs.h b/xen/include/asm-x86/x86_64/regs.h
index 3cdc702..2ea49c5 100644
--- a/xen/include/asm-x86/x86_64/regs.h
+++ b/xen/include/asm-x86/x86_64/regs.h
@@ -10,10 +10,11 @@
 #define ring_2(r)    (((r)->cs & 3) == 2)
 #define ring_3(r)    (((r)->cs & 3) == 3)
 
-#define guest_kernel_mode(v, r)                                 \
-    (!is_pv_32bit_vcpu(v) ?                                     \
-     (ring_3(r) && ((v)->arch.flags & TF_kernel_mode)) :        \
-     (ring_1(r)))
+#define guest_kernel_mode(v, r)                                   \
+    (is_pvh_vcpu(v) ? (ring_0(r)) :                               \
+     (!is_pv_32bit_vcpu(v) ?                                      \
+      (ring_3(r) && ((v)->arch.flags & TF_kernel_mode)) :         \
+      (ring_1(r))))
 
 #define permit_softint(dpl, v, r) \
     ((dpl) >= (guest_kernel_mode(v, r) ? 1 : 3))
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 4c5b2bb..6b1aa11 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -89,6 +89,9 @@ struct xen_domctl_getdomaininfo {
  /* Being debugged.  */
 #define _XEN_DOMINF_debugged  6
 #define XEN_DOMINF_debugged   (1U<<_XEN_DOMINF_debugged)
+/* domain is PVH */
+#define _XEN_DOMINF_pvh_guest 7
+#define XEN_DOMINF_pvh_guest   (1U<<_XEN_DOMINF_pvh_guest)
  /* XEN_DOMINF_shutdown guest-supplied code.  */
 #define XEN_DOMINF_shutdownmask 255
 #define XEN_DOMINF_shutdownshift 16
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index ae6a3b8..4d5edf5 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -238,6 +238,14 @@ struct mem_event_per_domain
     struct mem_event_domain access;
 };
 
+/*
+ * PVH is a PV guest running in an HVM container. While is_hvm_* checks are
+ * false for it, it uses many of the HVM data structs.
+ */
+enum guest_type {
+    is_pv, is_pvh, is_hvm
+};
+
 struct domain
 {
     domid_t          domain_id;
@@ -285,8 +293,8 @@ struct domain
     struct rangeset *iomem_caps;
     struct rangeset *irq_caps;
 
-    /* Is this an HVM guest? */
-    bool_t           is_hvm;
+    enum guest_type guest_type;
+
 #ifdef HAS_PASSTHROUGH
     /* Does this guest need iommu mappings? */
     bool_t           need_iommu;
@@ -464,6 +472,9 @@ struct domain *domain_create(
  /* DOMCRF_oos_off: dont use out-of-sync optimization for shadow page tables */
 #define _DOMCRF_oos_off         4
 #define DOMCRF_oos_off          (1U<<_DOMCRF_oos_off)
+ /* DOMCRF_pvh: Create PV domain in HVM container. */
+#define _DOMCRF_pvh            5
+#define DOMCRF_pvh             (1U<<_DOMCRF_pvh)
 
 /*
  * rcu_lock_domain_by_id() is more efficient than get_domain_by_id().
@@ -732,8 +743,12 @@ void watchdog_domain_destroy(struct domain *d);
 
 #define VM_ASSIST(_d,_t) (test_bit((_t), &(_d)->vm_assist))
 
-#define is_hvm_domain(d) ((d)->is_hvm)
+#define is_pv_domain(d) ((d)->guest_type == is_pv)
+#define is_pv_vcpu(v)   (is_pv_domain(v->domain))
+#define is_hvm_domain(d) ((d)->guest_type == is_hvm)
 #define is_hvm_vcpu(v)   (is_hvm_domain(v->domain))
+#define is_pvh_domain(d) ((d)->guest_type == is_pvh)
+#define is_pvh_vcpu(v)   (is_pvh_domain(v->domain))
 #define is_pinned_vcpu(v) ((v)->domain->is_pinned || \
                            cpumask_weight((v)->cpu_affinity) == 1)
 #ifdef HAS_PASSTHROUGH
-- 
1.7.2.3