diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 20bfa971a9..535c7e511b 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -644,7 +644,7 @@ unsigned int pci_size_mem_bar(pci_sbdf_t sbdf, unsigned int pos,
                               unsigned int flags)
 {
     uint32_t hi = 0, bar = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev,
-                                           sbdf.func, pos);
+                                           sbdf.fn, pos);
     uint64_t size;
     bool is64bits = !(flags & PCI_BAR_ROM) &&
         (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) == PCI_BASE_ADDRESS_MEM_TYPE_64;
@@ -654,7 +654,7 @@ unsigned int pci_size_mem_bar(pci_sbdf_t sbdf, unsigned int pos,
     ASSERT(!((flags & PCI_BAR_VF) && (flags & PCI_BAR_ROM)));
     ASSERT((flags & PCI_BAR_ROM) ||
            (bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_MEMORY);
-    pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, pos, ~0);
+    pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, pos, ~0);
     if ( is64bits )
     {
         if ( flags & PCI_BAR_LAST )
@@ -662,24 +662,24 @@ unsigned int pci_size_mem_bar(pci_sbdf_t sbdf, unsigned int pos,
             printk(XENLOG_WARNING
                    "%sdevice %04x:%02x:%02x.%u with 64-bit %sBAR in last slot\n",
                    (flags & PCI_BAR_VF) ? "SR-IOV " : "", sbdf.seg, sbdf.bus,
-                   sbdf.dev, sbdf.func, (flags & PCI_BAR_VF) ? "vf " : "");
+                   sbdf.dev, sbdf.fn, (flags & PCI_BAR_VF) ? "vf " : "");
             *psize = 0;
             return 1;
         }
-        hi = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, pos + 4);
-        pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, pos + 4, ~0);
+        hi = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, pos + 4);
+        pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, pos + 4, ~0);
     }
-    size = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func,
+    size = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn,
                            pos) & mask;
     if ( is64bits )
     {
         size |= (uint64_t)pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev,
-                                          sbdf.func, pos + 4) << 32;
-        pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, pos + 4, hi);
+                                          sbdf.fn, pos + 4) << 32;
+        pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, pos + 4, hi);
     }
     else if ( size )
         size |= (uint64_t)~0 << 32;
-    pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, pos, bar);
+    pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, pos, bar);
     size = -size;
 
     if ( paddr )
diff --git a/xen/drivers/vpci/vpci.c b/xen/drivers/vpci/vpci.c
index 82607bdb9a..b03232fe30 100644
--- a/xen/drivers/vpci/vpci.c
+++ b/xen/drivers/vpci/vpci.c
@@ -212,7 +212,7 @@ static uint32_t vpci_read_hw(pci_sbdf_t sbdf, unsigned int reg,
     switch ( size )
     {
     case 4:
-        data = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg);
+        data = pci_conf_read32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg);
         break;
 
     case 3:
@@ -222,26 +222,26 @@ static uint32_t vpci_read_hw(pci_sbdf_t sbdf, unsigned int reg,
          */
         if ( reg & 1 )
         {
-            data = pci_conf_read8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func,
+            data = pci_conf_read8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn,
                                   reg);
-            data |= pci_conf_read16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func,
+            data |= pci_conf_read16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn,
                                     reg + 1) << 8;
         }
         else
         {
-            data = pci_conf_read16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func,
+            data = pci_conf_read16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn,
                                    reg);
-            data |= pci_conf_read8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func,
+            data |= pci_conf_read8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn,
                                    reg + 2) << 16;
         }
         break;
 
     case 2:
-        data = pci_conf_read16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg);
+        data = pci_conf_read16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg);
         break;
 
     case 1:
-        data = pci_conf_read8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg);
+        data = pci_conf_read8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg);
         break;
 
     default:
@@ -259,7 +259,7 @@ static void vpci_write_hw(pci_sbdf_t sbdf, unsigned int reg, unsigned int size,
     switch ( size )
     {
     case 4:
-        pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg, data);
+        pci_conf_write32(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg, data);
         break;
 
     case 3:
@@ -269,26 +269,26 @@ static void vpci_write_hw(pci_sbdf_t sbdf, unsigned int reg, unsigned int size,
          */
         if ( reg & 1 )
         {
-            pci_conf_write8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg,
+            pci_conf_write8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg,
                             data);
-            pci_conf_write16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg + 1,
+            pci_conf_write16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg + 1,
                              data >> 8);
         }
         else
         {
-            pci_conf_write16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg,
+            pci_conf_write16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg,
                              data);
-            pci_conf_write8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg + 2,
+            pci_conf_write8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg + 2,
                             data >> 16);
         }
         break;
 
     case 2:
-        pci_conf_write16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg, data);
+        pci_conf_write16(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg, data);
         break;
 
     case 1:
-        pci_conf_write8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.func, reg, data);
+        pci_conf_write8(sbdf.seg, sbdf.bus, sbdf.dev, sbdf.fn, reg, data);
         break;
 
     default:
diff --git a/xen/include/xen/pci.h b/xen/include/xen/pci.h
index 53f50d89e7..dab1a86dd4 100644
--- a/xen/include/xen/pci.h
+++ b/xen/include/xen/pci.h
@@ -46,7 +46,7 @@ typedef union {
             struct {
                 union {
                     struct {
-                        uint8_t func : 3,
+                        uint8_t fn   : 3,
                                 dev  : 5;
                     };
                     uint8_t     extfunc;
