[PATCH 2/8] xen/domctl: Simplify DOMCTL_CDF_ checking logic

[Andrew Cooper]

Introduce some local variables to make the resulting logic easier to follow.
Join the two IOMMU checks in sanitise_domain_config().  Tweak some of the
terminology for better accuracy.

No functional change.

Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com>
---
CC: Jan Beulich <jbeul...@suse.com>
CC: Roger Pau Monné <roger....@citrix.com>
CC: Wei Liu <w...@xen.org>
---
 xen/arch/x86/domain.c |  7 ++++---
 xen/common/domain.c   | 32 ++++++++++++++++++++------------
 2 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 7e16d49bfd..d8f9be132c 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -629,6 +629,7 @@ void arch_vcpu_destroy(struct vcpu *v)
 int arch_sanitise_domain_config(struct xen_domctl_createdomain *config)
 {
     bool hvm = config->flags & XEN_DOMCTL_CDF_hvm;
+    bool hap = config->flags & XEN_DOMCTL_CDF_hap;
     unsigned int max_vcpus;
 
     if ( hvm ? !hvm_enabled : !IS_ENABLED(CONFIG_PV) )
@@ -653,13 +654,13 @@ int arch_sanitise_domain_config(struct 
xen_domctl_createdomain *config)
         return -EINVAL;
     }
 
-    if ( (config->flags & XEN_DOMCTL_CDF_hap) && !hvm_hap_supported() )
+    if ( hap && !hvm_hap_supported() )
     {
-        dprintk(XENLOG_INFO, "HAP requested but not supported\n");
+        dprintk(XENLOG_INFO, "HAP requested but not available\n");
         return -EINVAL;
     }
 
-    if ( !(config->flags & XEN_DOMCTL_CDF_hvm) )
+    if ( !hvm )
         /*
          * It is only meaningful for XEN_DOMCTL_CDF_oos_off to be clear
          * for HVM guests.
diff --git a/xen/common/domain.c b/xen/common/domain.c
index 8cfa2e0b6b..cb617dc5aa 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -299,6 +299,10 @@ static void _domain_destroy(struct domain *d)
 
 static int sanitise_domain_config(struct xen_domctl_createdomain *config)
 {
+    bool hvm = config->flags & XEN_DOMCTL_CDF_hvm;
+    bool hap = config->flags & XEN_DOMCTL_CDF_hap;
+    bool iommu = config->flags & XEN_DOMCTL_CDF_iommu;
+
     if ( config->flags & ~(XEN_DOMCTL_CDF_hvm |
                            XEN_DOMCTL_CDF_hap |
                            XEN_DOMCTL_CDF_s3_integrity |
@@ -310,30 +314,34 @@ static int sanitise_domain_config(struct 
xen_domctl_createdomain *config)
         return -EINVAL;
     }
 
-    if ( !(config->flags & XEN_DOMCTL_CDF_iommu) && config->iommu_opts )
-    {
-        dprintk(XENLOG_INFO,
-                "IOMMU options specified but IOMMU not enabled\n");
-        return -EINVAL;
-    }
-
     if ( config->max_vcpus < 1 )
     {
         dprintk(XENLOG_INFO, "No vCPUS\n");
         return -EINVAL;
     }
 
-    if ( !(config->flags & XEN_DOMCTL_CDF_hvm) &&
-         (config->flags & XEN_DOMCTL_CDF_hap) )
+    if ( hap && !hvm )
     {
         dprintk(XENLOG_INFO, "HAP requested for non-HVM guest\n");
         return -EINVAL;
     }
 
-    if ( (config->flags & XEN_DOMCTL_CDF_iommu) && !iommu_enabled )
+    if ( iommu )
     {
-        dprintk(XENLOG_INFO, "IOMMU is not enabled\n");
-        return -EINVAL;
+        if ( !iommu_enabled )
+        {
+            dprintk(XENLOG_INFO, "IOMMU requested but not available\n");
+            return -EINVAL;
+        }
+    }
+    else
+    {
+        if ( config->iommu_opts )
+        {
+            dprintk(XENLOG_INFO,
+                    "IOMMU options specified but IOMMU not requested\n");
+            return -EINVAL;
+        }
     }
 
     return arch_sanitise_domain_config(config);
-- 
2.11.0