[PATCH v2 3/3] PCI: bring pci_get_real_pdev() in line with pci_get_pdev()

[Jan Beulich <jbeulich@xxxxxxxx>]

Fold the three parameters into a single pci_sbdf_t one.

No functional change intended, despite the "(8 - stride)" ->
"stride" replacement (not really sure why it was written the more
complicated way originally).

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
v2: New.

--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -639,8 +639,7 @@ static void cf_check parse_ppr_log_entry
     struct pci_dev *pdev;
 
     pcidevs_lock();
-    pdev = pci_get_real_pdev(iommu->seg, PCI_BUS(device_id),
-                             PCI_DEVFN(device_id));
+    pdev = pci_get_real_pdev(PCI_SBDF(iommu->seg, device_id));
     pcidevs_unlock();
 
     if ( pdev )
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -576,20 +576,18 @@ int __init pci_ro_device(int seg, int bu
     return 0;
 }
 
-struct pci_dev *pci_get_real_pdev(int seg, int bus, int devfn)
+struct pci_dev *pci_get_real_pdev(pci_sbdf_t sbdf)
 {
     struct pci_dev *pdev;
     int stride;
 
-    if ( seg < 0 || bus < 0 || devfn < 0 )
-        return NULL;
-
-    for ( pdev = pci_get_pdev(NULL, PCI_SBDF(seg, bus, devfn)), stride = 4;
+    for ( pdev = pci_get_pdev(NULL, sbdf), stride = 4;
           !pdev && stride; stride >>= 1 )
     {
-        if ( !(devfn & (8 - stride)) )
+        if ( !(sbdf.devfn & stride) )
             continue;
-        pdev = pci_get_pdev(NULL, PCI_SBDF(seg, bus, devfn & ~(8 - stride)));
+        sbdf.devfn &= ~stride;
+        pdev = pci_get_pdev(NULL, sbdf);
         if ( pdev && stride != pdev->phantom_stride )
             pdev = NULL;
     }
@@ -1074,7 +1072,7 @@ void pci_check_disable_device(u16 seg, u
     u16 cword;
 
     pcidevs_lock();
-    pdev = pci_get_real_pdev(seg, bus, devfn);
+    pdev = pci_get_real_pdev(PCI_SBDF(seg, bus, devfn));
     if ( pdev )
     {
         if ( now < pdev->fault.time ||
--- a/xen/include/xen/pci.h
+++ b/xen/include/xen/pci.h
@@ -178,7 +178,7 @@ int pci_remove_device(u16 seg, u8 bus, u
 int pci_ro_device(int seg, int bus, int devfn);
 int pci_hide_device(unsigned int seg, unsigned int bus, unsigned int devfn);
 struct pci_dev *pci_get_pdev(const struct domain *d, pci_sbdf_t sbdf);
-struct pci_dev *pci_get_real_pdev(int seg, int bus, int devfn);
+struct pci_dev *pci_get_real_pdev(pci_sbdf_t sbdf);
 void pci_check_disable_device(u16 seg, u8 bus, u8 devfn);
 
 uint8_t pci_conf_read8(pci_sbdf_t sbdf, unsigned int reg);