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);
 	}
 
 	/*