PCI: Change pbus_size_mem() return values to be more conventional

pbus_size_mem() previously returned 0 for failure and 1 for success.
Change it to return -ENOSPC for failure and 0 for success.

No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 21 insertions, 14 deletions

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index b6585cb9bce7..12ab50ffdfea 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -915,6 +915,10 @@ static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
  *
  * Calculate the size of the bus and minimal alignment which
  * guarantees that all child resources fit in this size.
+ *
+ * Returns -ENOSPC if there's no available bus resource of the desired type.
+ * Otherwise, sets the bus resource start/end to indicate the required
+ * size, adds things to realloc_head (if supplied), and returns 0.
  */
 static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                          unsigned long type, unsigned long type2,
@@ -931,7 +935,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
         resource_size_t children_add_size = 0;
 
         if (!b_res)
-                return 0;
+                return -ENOSPC;
 
         memset(aligns, 0, sizeof(aligns));
         max_order = 0;
@@ -1003,7 +1007,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                                  "%pR to %pR (unused)\n", b_res,
                                  &bus->busn_res);
                 b_res->flags = 0;
-                return 1;
+                return 0;
         }
         b_res->start = min_align;
         b_res->end = size0 + min_align - 1;
@@ -1014,7 +1018,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                                  "%pR to %pR add_size %llx\n", b_res,
                                  &bus->busn_res, (unsigned long long)size1-size0);
         }
-        return 1;
+        return 0;
 }
 
 unsigned long pci_cardbus_resource_alignment(struct resource *res)
@@ -1126,6 +1130,7 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus,
         unsigned long mask, prefmask, type2 = 0, type3 = 0;
         resource_size_t additional_mem_size = 0, additional_io_size = 0;
         struct resource *b_res;
+        int ret;
 
         list_for_each_entry(dev, &bus->devices, bus_list) {
                 struct pci_bus *b = dev->subordinate;
@@ -1175,25 +1180,27 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus,
                 prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
                 if (b_res[2].flags & IORESOURCE_MEM_64) {
                         prefmask |= IORESOURCE_MEM_64;
-                        if (pbus_size_mem(bus, prefmask, prefmask,
+                        ret = pbus_size_mem(bus, prefmask, prefmask,
                                   prefmask, prefmask,
                                   realloc_head ? 0 : additional_mem_size,
-                                  additional_mem_size, realloc_head)) {
-                                        /*
-                                         * Success, with pref mmio64,
-                                         * next will size non-pref or
-                                         * non-mmio64 */
-                                        mask = prefmask;
-                                        type2 = prefmask & ~IORESOURCE_MEM_64;
-                                        type3 = prefmask & ~IORESOURCE_PREFETCH;
+                                  additional_mem_size, realloc_head);
+                        if (ret == 0) {
+                                /*
+                                 * Success, with pref mmio64,
+                                 * next will size non-pref or
+                                 * non-mmio64 */
+                                mask = prefmask;
+                                type2 = prefmask & ~IORESOURCE_MEM_64;
+                                type3 = prefmask & ~IORESOURCE_PREFETCH;
                         }
                 }
                 if (!type2) {
                         prefmask &= ~IORESOURCE_MEM_64;
-                        if (pbus_size_mem(bus, prefmask, prefmask,
+                        ret = pbus_size_mem(bus, prefmask, prefmask,
                                          prefmask, prefmask,
                                          realloc_head ? 0 : additional_mem_size,
-                                         additional_mem_size, realloc_head)) {
+                                         additional_mem_size, realloc_head);
+                        if (ret == 0) {
                                 /* Success, next will size non-prefetch. */
                                 mask = prefmask;
                         } else