x86: Move range related operation to one file

We have almost the same code for mtrr cleanup and amd_bus checkup, and
this code  will also be used in replacing bootmem with early_res,
so try to move them together and reuse it from different parts.

Also rename update_range to subtract_range as that is what the
function is actually doing.

-v2: update comments as Christoph requested

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-4-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 11 insertions, 59 deletions

diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
index 95ecbd495955..2356ea18697d 100644
--- a/arch/x86/pci/amd_bus.c
+++ b/arch/x86/pci/amd_bus.c
@@ -2,6 +2,8 @@
 #include <linux/pci.h>
 #include <linux/topology.h>
 #include <linux/cpu.h>
+#include <linux/range.h>
+
 #include <asm/pci_x86.h>
 
 #ifdef CONFIG_X86_64
@@ -17,58 +19,6 @@
 
 #ifdef CONFIG_X86_64
 
-#define RANGE_NUM 16
-
-struct res_range {
-        size_t start;
-        size_t end;
-};
-
-static void __init update_range(struct res_range *range, size_t start,
-                                size_t end)
-{
-        int i;
-        int j;
-
-        for (j = 0; j < RANGE_NUM; j++) {
-                if (!range[j].end)
-                        continue;
-
-                if (start <= range[j].start && end >= range[j].end) {
-                        range[j].start = 0;
-                        range[j].end = 0;
-                        continue;
-                }
-
-                if (start <= range[j].start && end < range[j].end && range[j].start < end + 1) {
-                        range[j].start = end + 1;
-                        continue;
-                }
-
-
-                if (start > range[j].start && end >= range[j].end && range[j].end > start - 1) {
-                        range[j].end = start - 1;
-                        continue;
-                }
-
-                if (start > range[j].start && end < range[j].end) {
-                        /* find the new spare */
-                        for (i = 0; i < RANGE_NUM; i++) {
-                                if (range[i].end == 0)
-                                        break;
-                        }
-                        if (i < RANGE_NUM) {
-                                range[i].end = range[j].end;
-                                range[i].start = end + 1;
-                        } else {
-                                printk(KERN_ERR "run of slot in ranges\n");
-                        }
-                        range[j].end = start - 1;
-                        continue;
-                }
-        }
-}
-
 struct pci_hostbridge_probe {
         u32 bus;
         u32 slot;
@@ -111,6 +61,8 @@ static void __init get_pci_mmcfg_amd_fam10h_range(void)
         fam10h_mmconf_end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
 }
 
+#define RANGE_NUM 16
+
 /**
  * early_fill_mp_bus_to_node()
  * called before pcibios_scan_root and pci_scan_bus
@@ -132,7 +84,7 @@ static int __init early_fill_mp_bus_info(void)
         struct resource *res;
         size_t start;
         size_t end;
-        struct res_range range[RANGE_NUM];
+        struct range range[RANGE_NUM];
         u64 val;
         u32 address;
 
@@ -226,7 +178,7 @@ static int __init early_fill_mp_bus_info(void)
                 if (end > 0xffff)
                         end = 0xffff;
                 update_res(info, start, end, IORESOURCE_IO, 1);
-                update_range(range, start, end);
+                subtract_range(range, RANGE_NUM, start, end);
         }
         /* add left over io port range to def node/link, [0, 0xffff] */
         /* find the position */
@@ -256,14 +208,14 @@ static int __init early_fill_mp_bus_info(void)
         end = (val & 0xffffff800000ULL);
         printk(KERN_INFO "TOM: %016lx aka %ldM\n", end, end>>20);
         if (end < (1ULL<<32))
-                update_range(range, 0, end - 1);
+                subtract_range(range, RANGE_NUM, 0, end - 1);
 
         /* get mmconfig */
         get_pci_mmcfg_amd_fam10h_range();
         /* need to take out mmconf range */
         if (fam10h_mmconf_end) {
                 printk(KERN_DEBUG "Fam 10h mmconf [%llx, %llx]\n", fam10h_mmconf_start, fam10h_mmconf_end);
-                update_range(range, fam10h_mmconf_start, fam10h_mmconf_end);
+                subtract_range(range, RANGE_NUM, fam10h_mmconf_start, fam10h_mmconf_end);
         }
 
         /* mmio resource */
@@ -318,7 +270,7 @@ static int __init early_fill_mp_bus_info(void)
                                 /* we got a hole */
                                 endx = fam10h_mmconf_start - 1;
                                 update_res(info, start, endx, IORESOURCE_MEM, 0);
-                                update_range(range, start, endx);
+                                subtract_range(range, RANGE_NUM, start, endx);
                                 printk(KERN_CONT " ==> [%llx, %llx]", (u64)start, endx);
                                 start = fam10h_mmconf_end + 1;
                                 changed = 1;
@@ -334,7 +286,7 @@ static int __init early_fill_mp_bus_info(void)
                 }
 
                 update_res(info, start, end, IORESOURCE_MEM, 1);
-                update_range(range, start, end);
+                subtract_range(range, RANGE_NUM, start, end);
                 printk(KERN_CONT "\n");
         }
 
@@ -349,7 +301,7 @@ static int __init early_fill_mp_bus_info(void)
                 rdmsrl(address, val);
                 end = (val & 0xffffff800000ULL);
                 printk(KERN_INFO "TOM2: %016lx aka %ldM\n", end, end>>20);
-                update_range(range, 1ULL<<32, end - 1);
+                subtract_range(range, RANGE_NUM, 1ULL<<32, end - 1);
         }
 
         /*