]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - arch/x86/kernel/resource.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kernel / resource.c
1 #include <linux/ioport.h>
2 #include <asm/e820.h>
3
4 static void resource_clip(struct resource *res, resource_size_t start,
5 resource_size_t end)
6 {
7 resource_size_t low = 0, high = 0;
8
9 if (res->end < start || res->start > end)
10 return; /* no conflict */
11
12 if (res->start < start)
13 low = start - res->start;
14
15 if (res->end > end)
16 high = res->end - end;
17
18 /* Keep the area above or below the conflict, whichever is larger */
19 if (low > high)
20 res->end = start - 1;
21 else
22 res->start = end + 1;
23 }
24
25 static void remove_e820_regions(struct resource *avail)
26 {
27 int i;
28 struct e820entry *entry;
29
30 for (i = 0; i < e820.nr_map; i++) {
31 entry = &e820.map[i];
32
33 resource_clip(avail, entry->addr,
34 entry->addr + entry->size - 1);
35 }
36 }
37
38 void arch_remove_reservations(struct resource *avail)
39 {
40 /*
41 * Trim out BIOS area (high 2MB) and E820 regions. We do not remove
42 * the low 1MB unconditionally, as this area is needed for some ISA
43 * cards requiring a memory range, e.g. the i82365 PCMCIA controller.
44 */
45 if (avail->flags & IORESOURCE_MEM) {
46 resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END);
47
48 remove_e820_regions(avail);
49 }
50 }