[RFC PATCH 8/16]: PVH xen: domain creation code changes

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

This patch mainly changes arch_domain_create() to allow for PVH
creation. Also, since PVH uses lot of HVM data structs and code paths,
in hvm_vcpu {} a sub struct to store in PVH specific info is created.
Right now it only has one field, but will grow over time.

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>

diff -r 956e77de73e4 -r e51e48fd1d20 xen/arch/x86/domain.c
--- a/xen/arch/x86/domain.c	Fri Jan 11 16:29:49 2013 -0800
+++ b/xen/arch/x86/domain.c	Fri Jan 11 16:31:33 2013 -0800
@@ -410,8 +410,11 @@ int vcpu_initialise(struct vcpu *v)
 
     vmce_init_vcpu(v);
 
-    if ( is_hvm_domain(d) )
+    if ( is_hvm_or_pvh_domain(d) )
     {
+        if ( is_pvh_domain(d) )
+            v->arch.hvm_vcpu.hvm_pvh.pvh_vcpu_info_mfn = INVALID_MFN;
+
         rc = hvm_vcpu_initialise(v);
         goto done;
     }
@@ -476,7 +479,7 @@ void vcpu_destroy(struct vcpu *v)
 
     vcpu_destroy_fpu(v);
 
-    if ( is_hvm_vcpu(v) )
+    if ( is_hvm_or_pvh_vcpu(v) )
         hvm_vcpu_destroy(v);
     else if ( standalone_trap_ctxt(v) )
         free_xenheap_page(v->arch.pv_vcpu.trap_ctxt);
@@ -489,7 +492,7 @@ int arch_domain_create(struct domain *d,
     int rc = -ENOMEM;
 
     d->arch.hvm_domain.hap_enabled =
-        is_hvm_domain(d) &&
+        is_hvm_or_pvh_domain(d) &&
         hvm_funcs.hap_supported &&
         (domcr_flags & DOMCRF_hap);
     d->arch.hvm_domain.mem_sharing_enabled = 0;
@@ -539,7 +542,7 @@ int arch_domain_create(struct domain *d,
                             __PAGE_HYPERVISOR);
 
     HYPERVISOR_COMPAT_VIRT_START(d) =
-        is_hvm_domain(d) ? ~0u : __HYPERVISOR_COMPAT_VIRT_START;
+        is_hvm_or_pvh_domain(d) ? ~0u : __HYPERVISOR_COMPAT_VIRT_START;
 
     if ( (rc = paging_domain_init(d, domcr_flags)) != 0 )
         goto fail;
@@ -581,7 +584,7 @@ int arch_domain_create(struct domain *d,
             goto fail;
     }
 
-    if ( is_hvm_domain(d) )
+    if ( is_hvm_or_pvh_domain(d) )
     {
         if ( (rc = hvm_domain_initialise(d)) != 0 )
         {
@@ -593,9 +596,9 @@ int arch_domain_create(struct domain *d,
     {
         /* 64-bit PV guest by default. */
         d->arch.is_32bit_pv = d->arch.has_32bit_shinfo = 0;
-
+    }
+    if ( !is_hvm_domain(d) )
         spin_lock_init(&d->arch.pv_domain.e820_lock);
-    }
 
     /* initialize default tsc behavior in case tools don't */
     tsc_set_info(d, TSC_MODE_DEFAULT, 0UL, 0, 0);
@@ -622,9 +625,10 @@ void arch_domain_destroy(struct domain *
 {
     unsigned int i;
 
-    if ( is_hvm_domain(d) )
+    if ( is_hvm_or_pvh_domain(d) )
         hvm_domain_destroy(d);
-    else
+
+    if ( !is_hvm_domain(d) )
         xfree(d->arch.pv_domain.e820);
 
     free_domain_pirqs(d);
@@ -683,6 +687,11 @@ int arch_set_info_guest(
     unsigned int i;
     int rc = 0, compat;
 
+#if 0
+    /* should we allow PV dom0 to create PVH domU's ???? */
+    if ( is_pvh_vcpu(v) && !is_pvh_vcpu(current) )
+        return -EINVAL;
+#endif
     /* 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);
@@ -690,7 +699,7 @@ int arch_set_info_guest(
 #define c(fld) (compat ? (c.cmp->fld) : (c.nat->fld))
     flags = c(flags);
 
-    if ( !is_hvm_vcpu(v) )
+    if ( !is_hvm_or_pvh_vcpu(v) )
     {
         if ( !compat )
         {
@@ -743,7 +752,7 @@ int arch_set_info_guest(
     v->fpu_initialised = !!(flags & VGCF_I387_VALID);
 
     v->arch.flags &= ~TF_kernel_mode;
-    if ( (flags & VGCF_in_kernel) || is_hvm_vcpu(v)/*???*/ )
+    if ( (flags & VGCF_in_kernel) || is_hvm_or_pvh_vcpu(v)/*???*/ )
         v->arch.flags |= TF_kernel_mode;
 
     v->arch.vgc_flags = flags;
@@ -752,7 +761,7 @@ int arch_set_info_guest(
     if ( !compat )
     {
         memcpy(&v->arch.user_regs, &c.nat->user_regs, sizeof(c.nat->user_regs));
-        if ( !is_hvm_vcpu(v) )
+        if ( !is_hvm_or_pvh_vcpu(v) )
             memcpy(v->arch.pv_vcpu.trap_ctxt, c.nat->trap_ctxt,
                    sizeof(c.nat->trap_ctxt));
     }
@@ -768,10 +777,13 @@ int arch_set_info_guest(
 
     v->arch.user_regs.eflags |= 2;
 
-    if ( is_hvm_vcpu(v) )
+    if ( is_hvm_or_pvh_vcpu(v) )
     {
         hvm_set_info_guest(v);
-        goto out;
+        if ( is_hvm_vcpu(v) || v->is_initialised )
+            goto out;
+        else 
+            goto pvh_skip_pv;;
     }
 
     init_int80_direct_trap(v);
@@ -780,7 +792,8 @@ int arch_set_info_guest(
     v->arch.pv_vcpu.iopl = (v->arch.user_regs.eflags >> 12) & 3;
     v->arch.user_regs.eflags &= ~X86_EFLAGS_IOPL;
 
-    /* Ensure real hardware interrupts are enabled. */
+    /* Ensure real hardware interrupts are enabled. Note: PVH may not have 
+     * IDT set on all vcpus so don't enable IF for it yet. */
     v->arch.user_regs.eflags |= X86_EFLAGS_IF;
 
     if ( !v->is_initialised )
@@ -876,6 +889,7 @@ int arch_set_info_guest(
     if ( rc != 0 )
         return rc;
 
+pvh_skip_pv:
     if ( !compat )
     {
         cr3_gfn = xen_cr3_to_pfn(c.nat->ctrlreg[3]);
@@ -883,19 +897,26 @@ int arch_set_info_guest(
 
         if ( !cr3_page )
         {
-            destroy_gdt(v);
+            if ( !is_pvh_vcpu(v) )
+                destroy_gdt(v);
             return -EINVAL;
         }
         if ( !paging_mode_refcounts(d)
              && !get_page_type(cr3_page, PGT_base_page_table) )
         {
             put_page(cr3_page);
-            destroy_gdt(v);
+            if ( !is_pvh_vcpu(v) )
+                destroy_gdt(v);
             return -EINVAL;
         }
 
+        if ( is_pvh_vcpu(v) ) {
+            v->arch.cr3 = page_to_mfn(cr3_page);
+            v->arch.hvm_vcpu.guest_cr[3] = c.nat->ctrlreg[3];
+        }
+
         v->arch.guest_table = pagetable_from_page(cr3_page);
-        if ( c.nat->ctrlreg[1] )
+        if ( c.nat->ctrlreg[1] && !is_pvh_vcpu(v) )
         {
             cr3_gfn = xen_cr3_to_pfn(c.nat->ctrlreg[1]);
             cr3_page = get_page_from_gfn(d, cr3_gfn, NULL, P2M_ALLOC);
@@ -920,7 +941,8 @@ int arch_set_info_guest(
         }
         else if ( !(flags & VGCF_in_kernel) )
         {
-            destroy_gdt(v);
+            if ( !is_pvh_vcpu(v) )
+                destroy_gdt(v);
             return -EINVAL;
         }
     }
@@ -961,6 +983,13 @@ int arch_set_info_guest(
 
     update_cr3(v);
 
+    if ( is_pvh_vcpu(v) )
+    {
+        /* guest is bringing up non-boot SMP vcpu */
+        if ( (rc=hvm_pvh_set_vcpu_info(v, c.nat)) != 0 )
+            return rc;
+    }
+
  out:
     if ( flags & VGCF_online )
         clear_bit(_VPF_down, &v->pause_flags);
@@ -991,16 +1020,21 @@ void arch_vcpu_reset(struct vcpu *v)
 static void
 unmap_vcpu_info(struct vcpu *v)
 {
-    unsigned long mfn;
+    unsigned long mfn, *mfnp;
 
-    if ( v->arch.pv_vcpu.vcpu_info_mfn == INVALID_MFN )
+    if ( is_pvh_vcpu(v) )
+        mfnp = &v->arch.hvm_vcpu.hvm_pvh.pvh_vcpu_info_mfn;
+    else
+        mfnp = &v->arch.pv_vcpu.vcpu_info_mfn;
+
+    mfn = *mfnp;
+    if ( mfn == INVALID_MFN )
         return;
 
-    mfn = v->arch.pv_vcpu.vcpu_info_mfn;
     unmap_domain_page_global(v->vcpu_info);
 
     v->vcpu_info = &dummy_vcpu_info;
-    v->arch.pv_vcpu.vcpu_info_mfn = INVALID_MFN;
+    *mfnp = INVALID_MFN;
 
     put_page_and_type(mfn_to_page(mfn));
 }
@@ -1011,7 +1045,7 @@ unmap_vcpu_info(struct vcpu *v)
  * of memory, and it sets a pending event to make sure that a pending
  * event doesn't get missed.
  */
-static int
+static noinline int
 map_vcpu_info(struct vcpu *v, unsigned long gfn, unsigned offset)
 {
     struct domain *d = v->domain;
@@ -1019,11 +1053,17 @@ map_vcpu_info(struct vcpu *v, unsigned l
     vcpu_info_t *new_info;
     struct page_info *page;
     int i;
+    unsigned long *mfnp;
+
+    if ( is_pvh_vcpu(v) )
+        mfnp = &v->arch.hvm_vcpu.hvm_pvh.pvh_vcpu_info_mfn;
+    else
+        mfnp = &v->arch.pv_vcpu.vcpu_info_mfn;
 
     if ( offset > (PAGE_SIZE - sizeof(vcpu_info_t)) )
         return -EINVAL;
 
-    if ( v->arch.pv_vcpu.vcpu_info_mfn != INVALID_MFN )
+    if ( *mfnp != INVALID_MFN )
         return -EINVAL;
 
     /* Run this command on yourself or on other offline VCPUS. */
@@ -1060,7 +1100,7 @@ map_vcpu_info(struct vcpu *v, unsigned l
     }
 
     v->vcpu_info = new_info;
-    v->arch.pv_vcpu.vcpu_info_mfn = page_to_mfn(page);
+    *mfnp = page_to_mfn(page);
 
     /* Set new vcpu_info pointer /before/ setting pending flags. */
     wmb();
@@ -1466,7 +1506,7 @@ static void update_runstate_area(struct 
 
 static inline int need_full_gdt(struct vcpu *v)
 {
-    return (!is_hvm_vcpu(v) && !is_idle_vcpu(v));
+    return (!is_hvm_or_pvh_vcpu(v) && !is_idle_vcpu(v));
 }
 
 static void __context_switch(void)
@@ -1593,7 +1633,7 @@ void context_switch(struct vcpu *prev, s
         /* Re-enable interrupts before restoring state which may fault. */
         local_irq_enable();
 
-        if ( !is_hvm_vcpu(next) )
+        if ( !is_hvm_or_pvh_vcpu(next) )
         {
             load_LDT(next);
             load_segments(next);
@@ -1717,7 +1757,7 @@ unsigned long hypercall_create_continuat
         else
             current->arch.hvm_vcpu.hcall_preempted = 1;
 
-        if ( !is_hvm_vcpu(current) ?
+        if ( !is_hvm_or_pvh_vcpu(current) ?
              !is_pv_32on64_vcpu(current) :
              (hvm_guest_x86_mode(current) == 8) )
         {
@@ -2034,7 +2074,7 @@ int domain_relinquish_resources(struct d
         for_each_vcpu ( d, v )
             vcpu_destroy_pagetables(v);
 
-        if ( !is_hvm_domain(d) )
+        if ( !is_hvm_or_pvh_domain(d) )
         {
             for_each_vcpu ( d, v )
             {
@@ -2109,7 +2149,7 @@ int domain_relinquish_resources(struct d
         BUG();
     }
 
-    if ( is_hvm_domain(d) )
+    if ( is_hvm_or_pvh_domain(d) )
         hvm_domain_relinquish_resources(d);
 
     return 0;
@@ -2190,7 +2230,7 @@ void vcpu_mark_events_pending(struct vcp
     if ( already_pending )
         return;
 
-    if ( is_hvm_vcpu(v) )
+    if ( is_hvm_or_pvh_vcpu(v) )
         hvm_assert_evtchn_irq(v);
     else
         vcpu_kick(v);
diff -r 956e77de73e4 -r e51e48fd1d20 xen/include/asm-x86/hvm/hvm.h
--- a/xen/include/asm-x86/hvm/hvm.h	Fri Jan 11 16:29:49 2013 -0800
+++ b/xen/include/asm-x86/hvm/hvm.h	Fri Jan 11 16:31:33 2013 -0800
@@ -183,6 +183,12 @@ struct hvm_function_table {
     /* Virtual interrupt delivery */
     void (*update_eoi_exit_bitmap)(struct vcpu *v, u8 vector, u8 trig);
     int (*virtual_intr_delivery_enabled)(void);
+
+    /* PVH functions */
+    int (*pvh_set_vcpu_info)(struct vcpu *v, struct vcpu_guest_context *ctxtp);
+    int (*pvh_read_descriptor)(unsigned int sel, const struct vcpu *v,
+                         const struct cpu_user_regs *regs, unsigned long *base,
+                         unsigned long *limit, unsigned int *ar);
 };
 
 extern struct hvm_function_table hvm_funcs;
@@ -316,6 +322,19 @@ static inline unsigned long hvm_get_shad
     return hvm_funcs.get_shadow_gs_base(v);
 }
 
+static inline int hvm_pvh_set_vcpu_info(struct vcpu *v, 
+                                        struct vcpu_guest_context *ctxtp)
+{
+    return hvm_funcs.pvh_set_vcpu_info(v, ctxtp);
+}
+
+static inline int hvm_pvh_read_descriptor(unsigned int sel, 
+               const struct vcpu *v, const struct cpu_user_regs *regs, 
+               unsigned long *base, unsigned long *limit, unsigned int *ar)
+{
+    return hvm_funcs.pvh_read_descriptor(sel, v, regs, base, limit, ar);
+}
+
 #define is_viridian_domain(_d)                                             \
  (is_hvm_domain(_d) && ((_d)->arch.hvm_domain.params[HVM_PARAM_VIRIDIAN]))
 
diff -r 956e77de73e4 -r e51e48fd1d20 xen/include/asm-x86/hvm/vcpu.h
--- a/xen/include/asm-x86/hvm/vcpu.h	Fri Jan 11 16:29:49 2013 -0800
+++ b/xen/include/asm-x86/hvm/vcpu.h	Fri Jan 11 16:31:33 2013 -0800
@@ -104,6 +104,13 @@ struct nestedvcpu {
 
 #define vcpu_nestedhvm(v) ((v)->arch.hvm_vcpu.nvcpu)
 
+/* add any PVH specific fields here */
+struct pvh_hvm_vcpu_ext
+{
+    /* Guest-specified relocation of vcpu_info. */
+    unsigned long pvh_vcpu_info_mfn;
+};
+
 struct hvm_vcpu {
     /* Guest control-register and EFER values, just as the guest sees them. */
     unsigned long       guest_cr[5];
@@ -170,6 +177,8 @@ struct hvm_vcpu {
     struct hvm_trap     inject_trap;
 
     struct viridian_vcpu viridian;
+
+    struct pvh_hvm_vcpu_ext hvm_pvh;
 };
 
 #endif /* __ASM_X86_HVM_VCPU_H__ */