[PATCH v8 5/7] PCI: Allow pci_bus_for_each_resource() to take less arguments

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

Refactor pci_bus_for_each_resource() in the same way as it's done in
pci_dev_for_each_resource() case. This will allow to hide iterator
inside the loop, where it's not used otherwise.

No functional changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Krzysztof Wilczyński <kw@xxxxxxxxx>
Reviewed-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
---
 drivers/pci/bus.c                  |  7 +++----
 drivers/pci/hotplug/shpchp_sysfs.c |  8 ++++----
 drivers/pci/pci.c                  |  3 +--
 drivers/pci/probe.c                |  2 +-
 drivers/pci/setup-bus.c            | 10 ++++------
 include/linux/pci.h                | 24 +++++++++++++++++++-----
 6 files changed, 32 insertions(+), 22 deletions(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 549c4bd5caec..5bc81cc0a2de 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -182,13 +182,13 @@ static int pci_bus_alloc_from_region(struct pci_bus *bus, 
struct resource *res,
                void *alignf_data,
                struct pci_bus_region *region)
 {
-       int i, ret;
        struct resource *r, avail;
        resource_size_t max;
+       int ret;
 
        type_mask |= IORESOURCE_TYPE_BITS;
 
-       pci_bus_for_each_resource(bus, r, i) {
+       pci_bus_for_each_resource(bus, r) {
                resource_size_t min_used = min;
 
                if (!r)
@@ -289,9 +289,8 @@ bool pci_bus_clip_resource(struct pci_dev *dev, int idx)
        struct resource *res = &dev->resource[idx];
        struct resource orig_res = *res;
        struct resource *r;
-       int i;
 
-       pci_bus_for_each_resource(bus, r, i) {
+       pci_bus_for_each_resource(bus, r) {
                resource_size_t start, end;
 
                if (!r)
diff --git a/drivers/pci/hotplug/shpchp_sysfs.c 
b/drivers/pci/hotplug/shpchp_sysfs.c
index 64beed7a26be..01d47a42da04 100644
--- a/drivers/pci/hotplug/shpchp_sysfs.c
+++ b/drivers/pci/hotplug/shpchp_sysfs.c
@@ -24,16 +24,16 @@
 static ssize_t show_ctrl(struct device *dev, struct device_attribute *attr, 
char *buf)
 {
        struct pci_dev *pdev;
-       int index, busnr;
        struct resource *res;
        struct pci_bus *bus;
        size_t len = 0;
+       int busnr;
 
        pdev = to_pci_dev(dev);
        bus = pdev->subordinate;
 
        len += sysfs_emit_at(buf, len, "Free resources: memory\n");
-       pci_bus_for_each_resource(bus, res, index) {
+       pci_bus_for_each_resource(bus, res) {
                if (res && (res->flags & IORESOURCE_MEM) &&
                                !(res->flags & IORESOURCE_PREFETCH)) {
                        len += sysfs_emit_at(buf, len,
@@ -43,7 +43,7 @@ static ssize_t show_ctrl(struct device *dev, struct 
device_attribute *attr, char
                }
        }
        len += sysfs_emit_at(buf, len, "Free resources: prefetchable memory\n");
-       pci_bus_for_each_resource(bus, res, index) {
+       pci_bus_for_each_resource(bus, res) {
                if (res && (res->flags & IORESOURCE_MEM) &&
                               (res->flags & IORESOURCE_PREFETCH)) {
                        len += sysfs_emit_at(buf, len,
@@ -53,7 +53,7 @@ static ssize_t show_ctrl(struct device *dev, struct 
device_attribute *attr, char
                }
        }
        len += sysfs_emit_at(buf, len, "Free resources: IO\n");
-       pci_bus_for_each_resource(bus, res, index) {
+       pci_bus_for_each_resource(bus, res) {
                if (res && (res->flags & IORESOURCE_IO)) {
                        len += sysfs_emit_at(buf, len,
                                             "start = %8.8llx, length = 
%8.8llx\n",
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 45c3bb039f21..585bb3988ddf 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -779,9 +779,8 @@ struct resource *pci_find_parent_resource(const struct 
pci_dev *dev,
 {
        const struct pci_bus *bus = dev->bus;
        struct resource *r;
-       int i;
 
-       pci_bus_for_each_resource(bus, r, i) {
+       pci_bus_for_each_resource(bus, r) {
                if (!r)
                        continue;
                if (resource_contains(r, res)) {
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index a3f68b6ba6ac..f8191750f6b7 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -533,7 +533,7 @@ void pci_read_bridge_bases(struct pci_bus *child)
        pci_read_bridge_mmio_pref(child);
 
        if (dev->transparent) {
-               pci_bus_for_each_resource(child->parent, res, i) {
+               pci_bus_for_each_resource(child->parent, res) {
                        if (res && res->flags) {
                                pci_bus_add_resource(child, res,
                                                     PCI_SUBTRACTIVE_DECODE);
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 027b985dd1ee..fdeb121e9175 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -770,9 +770,8 @@ static struct resource *find_bus_resource_of_type(struct 
pci_bus *bus,
                                                  unsigned long type)
 {
        struct resource *r, *r_assigned = NULL;
-       int i;
 
-       pci_bus_for_each_resource(bus, r, i) {
+       pci_bus_for_each_resource(bus, r) {
                if (r == &ioport_resource || r == &iomem_resource)
                        continue;
                if (r && (r->flags & type_mask) == type && !r->parent)
@@ -1204,7 +1203,7 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct 
list_head *realloc_head)
                        additional_mmio_pref_size = 0;
        struct resource *pref;
        struct pci_host_bridge *host;
-       int hdr_type, i, ret;
+       int hdr_type, ret;
 
        list_for_each_entry(dev, &bus->devices, bus_list) {
                struct pci_bus *b = dev->subordinate;
@@ -1228,7 +1227,7 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct 
list_head *realloc_head)
                host = to_pci_host_bridge(bus->bridge);
                if (!host->size_windows)
                        return;
-               pci_bus_for_each_resource(bus, pref, i)
+               pci_bus_for_each_resource(bus, pref)
                        if (pref && (pref->flags & IORESOURCE_PREFETCH))
                                break;
                hdr_type = -1;  /* Intentionally invalid - not a PCI device. */
@@ -1333,12 +1332,11 @@ EXPORT_SYMBOL(pci_bus_size_bridges);
 
 static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r)
 {
-       int i;
        struct resource *parent_r;
        unsigned long mask = IORESOURCE_IO | IORESOURCE_MEM |
                             IORESOURCE_PREFETCH;
 
-       pci_bus_for_each_resource(b, parent_r, i) {
+       pci_bus_for_each_resource(b, parent_r) {
                if (!parent_r)
                        continue;
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e3b3af606280..56670d016cac 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1446,11 +1446,21 @@ int devm_request_pci_bus_resources(struct device *dev,
 /* Temporary until new and working PCI SBR API in place */
 int pci_bridge_secondary_bus_reset(struct pci_dev *dev);
 
+#define __pci_bus_for_each_res0(bus, res, ...)                         \
+       for (unsigned int __b = 0;                                      \
+            (res = pci_bus_resource_n(bus, __b)) || __b < 
PCI_BRIDGE_RESOURCE_NUM; \
+            __b++)
+
+#define __pci_bus_for_each_res1(bus, res, __b)                         \
+       for (__b = 0;                                                   \
+            (res = pci_bus_resource_n(bus, __b)) || __b < 
PCI_BRIDGE_RESOURCE_NUM; \
+            __b++)
+
 /**
  * pci_bus_for_each_resource - iterate over PCI bus resources
  * @bus: the PCI bus
  * @res: a varible to keep a pointer to the current resource
- * @i: a variable to keep the index of the current resource
+ * @...: an optional variable to keep the index of the current resource
  *
  * Iterate over PCI bus resources. The first part is to go over PCI bus
  * resource array, which has at most the %PCI_BRIDGE_RESOURCE_NUM entries.
@@ -1463,13 +1473,17 @@ int pci_bridge_secondary_bus_reset(struct pci_dev *dev);
  *     struct resource *res;
  *     unsigned int i;
  *
+ *     // With an additional index variable
  *     pci_bus_for_each_resource(bus, res, i)
  *             pr_info("PCI bus resource[%u]: %pR\n", i, res);
+ *
+ *     // Without index
+ *     pci_bus_for_each_resource(bus, res)
+ *             _do_something_(res);
  */
-#define pci_bus_for_each_resource(bus, res, i)                         \
-       for (i = 0;                                                     \
-           (res = pci_bus_resource_n(bus, i)) || i < PCI_BRIDGE_RESOURCE_NUM; \
-            i++)
+#define pci_bus_for_each_resource(bus, res, ...)                       \
+       CONCATENATE(__pci_bus_for_each_res, COUNT_ARGS(__VA_ARGS__))    \
+                   (bus, res, __VA_ARGS__)
 
 int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
                        struct resource *res, resource_size_t size,
-- 
2.40.0.1.gaa8946217a0b