x86/domain: factor out pv_domain_initialise

Lump everything PV related in arch_domain_create into
pv_domain_initialise.

Though domcr_flags and config are not necessary, the new function is
given those to match hvm counterpart.

Since it cleans up after itself there is no need to clean up in
arch_domain_create in case of failure. Remove the initialiser of rc in
arch_domain_create.

No functional change.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 0046661b6f220d2a9fad47b65754a3b90001b817..f610edffef6e7b5ba815c7ff12ceb8951f04099b 100644 (file)
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -550,11 +550,54 @@ static void pv_domain_destroy(struct domain *d)
     d->arch.pv_domain.gdt_ldt_l1tab = NULL;
 }
 
+static int pv_domain_initialise(struct domain *d, unsigned int domcr_flags,
+                                struct xen_arch_domainconfig *config)
+{
+    static const struct arch_csw pv_csw = {
+        .from = paravirt_ctxt_switch_from,
+        .to   = paravirt_ctxt_switch_to,
+        .tail = continue_nonidle_domain,
+    };
+    int rc = -ENOMEM;
+
+    d->arch.pv_domain.gdt_ldt_l1tab =
+        alloc_xenheap_pages(0, MEMF_node(domain_to_node(d)));
+    if ( !d->arch.pv_domain.gdt_ldt_l1tab )
+        goto fail;
+    clear_page(d->arch.pv_domain.gdt_ldt_l1tab);
+
+    if ( levelling_caps & ~LCAP_faulting )
+    {
+        d->arch.pv_domain.cpuidmasks = xmalloc(struct cpuidmasks);
+        if ( !d->arch.pv_domain.cpuidmasks )
+            goto fail;
+        *d->arch.pv_domain.cpuidmasks = cpuidmask_defaults;
+    }
+
+    rc = create_perdomain_mapping(d, GDT_LDT_VIRT_START,
+                                  GDT_LDT_MBYTES << (20 - PAGE_SHIFT),
+                                  NULL, NULL);
+    if ( rc )
+        goto fail;
+
+    d->arch.ctxt_switch = &pv_csw;
+
+    /* 64-bit PV guest by default. */
+    d->arch.is_32bit_pv = d->arch.has_32bit_shinfo = 0;
+
+    return 0;
+
+ fail:
+    pv_domain_destroy(d);
+
+    return rc;
+}
+
 int arch_domain_create(struct domain *d, unsigned int domcr_flags,
                        struct xen_arch_domainconfig *config)
 {
     bool paging_initialised = false;
-    int rc = -ENOMEM;
+    int rc;
 
     if ( config == NULL && !is_idle_domain(d) )
         return -EINVAL;
@@ -610,30 +653,6 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags,
         d->arch.emulation_flags = emflags;
     }
 
-    rc = 0; /* HVM and idle domain */
-    if ( is_pv_domain(d) )
-    {
-        d->arch.pv_domain.gdt_ldt_l1tab =
-            alloc_xenheap_pages(0, MEMF_node(domain_to_node(d)));
-        if ( !d->arch.pv_domain.gdt_ldt_l1tab )
-            goto fail;
-        clear_page(d->arch.pv_domain.gdt_ldt_l1tab);
-
-        if ( levelling_caps & ~LCAP_faulting )
-        {
-            d->arch.pv_domain.cpuidmasks = xmalloc(struct cpuidmasks);
-            if ( !d->arch.pv_domain.cpuidmasks )
-                goto fail;
-            *d->arch.pv_domain.cpuidmasks = cpuidmask_defaults;
-        }
-
-        rc = create_perdomain_mapping(d, GDT_LDT_VIRT_START,
-                                      GDT_LDT_MBYTES << (20 - PAGE_SHIFT),
-                                      NULL, NULL);
-    }
-    if ( rc )
-        goto fail;
-
     mapcache_domain_init(d);
 
     HYPERVISOR_COMPAT_VIRT_START(d) =
@@ -686,23 +705,20 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags,
         if ( (rc = hvm_domain_initialise(d, domcr_flags, config)) != 0 )
             goto fail;
     }
-    else
+    else if ( is_idle_domain(d) )
     {
-        static const struct arch_csw pv_csw = {
-            .from = paravirt_ctxt_switch_from,
-            .to   = paravirt_ctxt_switch_to,
-            .tail = continue_nonidle_domain,
-        };
         static const struct arch_csw idle_csw = {
             .from = paravirt_ctxt_switch_from,
             .to   = paravirt_ctxt_switch_to,
             .tail = continue_idle_domain,
         };
 
-        d->arch.ctxt_switch = is_idle_domain(d) ? &idle_csw : &pv_csw;
-
-        /* 64-bit PV guest by default. */
-        d->arch.is_32bit_pv = d->arch.has_32bit_shinfo = 0;
+        d->arch.ctxt_switch = &idle_csw;
+    }
+    else
+    {
+        if ( (rc = pv_domain_initialise(d, domcr_flags, config)) != 0 )
+            goto fail;
     }
 
     /* initialize default tsc behavior in case tools don't */
@@ -729,8 +745,6 @@ int arch_domain_create(struct domain *d, unsigned int domcr_flags,
     xfree(d->arch.cpuid);
     if ( paging_initialised )
         paging_final_teardown(d);
-    if ( is_pv_domain(d) )
-        pv_domain_destroy(d);
     free_perdomain_mappings(d);
 
     return rc;