[PATCH v5 7/9] vpci: split vpci_process_pending()

[Stewart Hildebrand <stewart.hildebrand@xxxxxxx>]

Create a new function to separate the mapping logic from the pdev
validation and lock-acquiring logic. Slightly consolidate exit paths for
hardware_domain and !hardware_domain.

No functional change.

Signed-off-by: Stewart Hildebrand <stewart.hildebrand@xxxxxxx>
---
v4->v5:
* new patch
---
 xen/drivers/vpci/header.c | 65 +++++++++++++++++++++++----------------
 1 file changed, 38 insertions(+), 27 deletions(-)

diff --git a/xen/drivers/vpci/header.c b/xen/drivers/vpci/header.c
index 28e051f2779c..f7eaf9c6ddf2 100644
--- a/xen/drivers/vpci/header.c
+++ b/xen/drivers/vpci/header.c
@@ -102,23 +102,12 @@ static int cf_check map_range(
     return rc;
 }
 
-bool vpci_process_pending(struct vcpu *v)
+static int process_map_task(const struct pci_dev *pdev, bool map)
 {
-    const struct pci_dev *pdev = v->vpci.pdev;
     struct vpci_header *header = NULL;
     unsigned int i;
 
-    if ( !pdev )
-        return false;
-
-    read_lock(&v->domain->pci_lock);
-
-    if ( !pdev->vpci || (v->domain != pdev->domain) )
-    {
-        v->vpci.pdev = NULL;
-        read_unlock(&v->domain->pci_lock);
-        return false;
-    }
+    ASSERT(rw_is_locked(&pdev->domain->pci_lock));
 
     header = &pdev->vpci->header;
     for ( i = 0; i < ARRAY_SIZE(header->bars); i++ )
@@ -126,8 +115,8 @@ bool vpci_process_pending(struct vcpu *v)
         struct vpci_bar *bar = &header->bars[i];
         struct rangeset *mem = bar->mem;
         struct map_data data = {
-            .d = v->domain,
-            .map = v->vpci.cmd & PCI_COMMAND_MEMORY,
+            .d = pdev->domain,
+            .map = map,
             .bar = bar,
         };
         int rc;
@@ -136,21 +125,12 @@ bool vpci_process_pending(struct vcpu *v)
             continue;
 
         rc = rangeset_consume_ranges(mem, map_range, &data);
-
         if ( rc == -ERESTART )
-        {
-            read_unlock(&v->domain->pci_lock);
-            return true;
-        }
-
-        if ( rc && !is_hardware_domain(v->domain) )
-        {
-            read_unlock(&v->domain->pci_lock);
+            return rc;
 
-            domain_crash(v->domain);
+        if ( rc && !is_hardware_domain(pdev->domain) )
+            return rc;
 
-            return false;
-        }
         ASSERT(!rc);
         /*
          * Purge rangeset to deal with the hardware domain having triggered an
@@ -160,10 +140,41 @@ bool vpci_process_pending(struct vcpu *v)
          */
         rangeset_purge(bar->mem);
     }
+
+    return 0;
+}
+
+bool vpci_process_pending(struct vcpu *v)
+{
+    const struct pci_dev *pdev = v->vpci.pdev;
+    int rc;
+
+    if ( !pdev )
+        return false;
+
+    read_lock(&v->domain->pci_lock);
+
+    if ( !pdev->vpci || (v->domain != pdev->domain) )
+    {
+        v->vpci.pdev = NULL;
+        read_unlock(&v->domain->pci_lock);
+        return false;
+    }
+
+    rc = process_map_task(pdev, v->vpci.cmd & PCI_COMMAND_MEMORY);
+    if ( rc == -ERESTART )
+    {
+        read_unlock(&v->domain->pci_lock);
+        return true;
+    }
+
     v->vpci.pdev = NULL;
 
     read_unlock(&v->domain->pci_lock);
 
+    if ( rc && !is_hardware_domain(v->domain) )
+        domain_crash(v->domain);
+
     return false;
 }
 
-- 
2.54.0