[PATCH v2 3/3] xen/vpci: msix: move read/write call to MSI-X PBA entry to arch file

From: Rahul Singh <rahul.singh@arm.com>
To: xen-devel@lists.xenproject.org
Cc: bertrand.marquis@arm.com, rahul.singh@arm.com,
	"Jan Beulich" <jbeulich@suse.com>,
	"Andrew Cooper" <andrew.cooper3@citrix.com>,
	"Roger Pau Monné" <roger.pau@citrix.com>, "Wei Liu" <wl@xen.org>
Subject: [PATCH v2 3/3] xen/vpci: msix: move read/write call to MSI-X PBA entry to arch file
Date: Tue, 15 Feb 2022 15:25:18 +0000	[thread overview]
Message-ID: <3e47316052dce3c85bde04ab6b72ba4f48fa0bb8.1644937405.git.rahul.singh@arm.com> (raw)
In-Reply-To: <cover.1644937405.git.rahul.singh@arm.com>

{read,write}{l,q} function argument is different for ARM and x86.
ARM {read,wrie}(l,q} function argument is pointer whereas X86
{read,wrie}(l,q} function argument is address itself.

{read,write}{l,q} is only used in common file to access the MSI-X PBA
structure. To avoid impacting other x86 code and to make the code common
move the read/write call to MSI-X PBA to arch specific file.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
---
Changes since v1:
 - Added in this version
---
 xen/arch/x86/hvm/vmsi.c | 47 +++++++++++++++++++++++++++++++++++++++++
 xen/drivers/vpci/msix.c | 43 ++-----------------------------------
 xen/include/xen/vpci.h  |  6 ++++++
 3 files changed, 55 insertions(+), 41 deletions(-)

diff --git a/xen/arch/x86/hvm/vmsi.c b/xen/arch/x86/hvm/vmsi.c
index 761ce674d7..f124a1d07d 100644
--- a/xen/arch/x86/hvm/vmsi.c
+++ b/xen/arch/x86/hvm/vmsi.c
@@ -1033,4 +1033,51 @@ void vpci_msix_arch_register(struct vpci_msix *msix, struct domain *d)
 
     list_add(&msix->next, &d->arch.hvm.msix_tables);
 }
+
+bool vpci_msix_arch_pba_read(unsigned long addr, unsigned int len,
+                             unsigned long *data)
+{
+    /*
+     * Access to PBA.
+     *
+     * TODO: note that this relies on having the PBA identity mapped to the
+     * guest address space. If this changes the address will need to be
+     * translated.
+     */
+    switch ( len )
+    {
+    case 4:
+        *data = readl(addr);
+        break;
+
+    case 8:
+        *data = readq(addr);
+        break;
+
+    default:
+        ASSERT_UNREACHABLE();
+        break;
+    }
+
+    return true;
+}
+
+void vpci_msix_arch_pba_write(unsigned long addr, unsigned int len,
+                              unsigned long data)
+{
+    switch ( len )
+    {
+    case 4:
+        writel(data, addr);
+        break;
+
+    case 8:
+        writeq(data, addr);
+        break;
+
+    default:
+        ASSERT_UNREACHABLE();
+        break;
+    }
+}
 #endif /* CONFIG_HAS_VPCI */
diff --git a/xen/drivers/vpci/msix.c b/xen/drivers/vpci/msix.c
index 5b315757ef..b6720f1a1a 100644
--- a/xen/drivers/vpci/msix.c
+++ b/xen/drivers/vpci/msix.c
@@ -170,31 +170,7 @@ bool vpci_msix_read(struct vpci_msix *msix, unsigned long addr,
         return true;
 
     if ( VMSIX_ADDR_IN_RANGE(addr, msix->pdev->vpci, VPCI_MSIX_PBA) )
-    {
-        /*
-         * Access to PBA.
-         *
-         * TODO: note that this relies on having the PBA identity mapped to the
-         * guest address space. If this changes the address will need to be
-         * translated.
-         */
-        switch ( len )
-        {
-        case 4:
-            *data = readl(addr);
-            break;
-
-        case 8:
-            *data = readq(addr);
-            break;
-
-        default:
-            ASSERT_UNREACHABLE();
-            break;
-        }
-
-        return true;
-    }
+        return vpci_msix_arch_pba_read(addr, len, data);
 
     spin_lock(&msix->pdev->vpci->lock);
     entry = get_entry(msix, addr);
@@ -247,22 +223,7 @@ bool vpci_msix_write(struct vpci_msix *msix, unsigned long addr,
     {
         /* Ignore writes to PBA for DomUs, it's behavior is undefined. */
         if ( is_hardware_domain(d) )
-        {
-            switch ( len )
-            {
-            case 4:
-                writel(data, addr);
-                break;
-
-            case 8:
-                writeq(data, addr);
-                break;
-
-            default:
-                ASSERT_UNREACHABLE();
-                break;
-            }
-        }
+            vpci_msix_arch_pba_write(addr, len, data);
 
         return true;
     }
diff --git a/xen/include/xen/vpci.h b/xen/include/xen/vpci.h
index 1c36845abf..a61daf9d53 100644
--- a/xen/include/xen/vpci.h
+++ b/xen/include/xen/vpci.h
@@ -231,6 +231,12 @@ bool vpci_msix_write(struct vpci_msix *msix, unsigned long addr,
 bool vpci_msix_read(struct vpci_msix *msix, unsigned long addr,
                     unsigned int len, unsigned long *data);
 
+bool vpci_msix_arch_pba_read(unsigned long addr, unsigned int len,
+                             unsigned long *data);
+
+void vpci_msix_arch_pba_write(unsigned long addr, unsigned int len,
+                              unsigned long data);
+
 #endif /* __XEN__ */
 
 #else /* !CONFIG_HAS_VPCI */
-- 
2.25.1


