linux/arch/x86/kernel/resource.c
Denys Vlasenko 475339684e x86/e820: Prepare e280 code for switch to dynamic storage
This patch turns e820 and e820_saved into pointers to e820 tables,
of the same size as before.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160917213927.1787-2-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-21 15:02:12 +02:00

51 lines
1.1 KiB
C

#include <linux/ioport.h>
#include <asm/e820.h>
static void resource_clip(struct resource *res, resource_size_t start,
resource_size_t end)
{
resource_size_t low = 0, high = 0;
if (res->end < start || res->start > end)
return; /* no conflict */
if (res->start < start)
low = start - res->start;
if (res->end > end)
high = res->end - end;
/* Keep the area above or below the conflict, whichever is larger */
if (low > high)
res->end = start - 1;
else
res->start = end + 1;
}
static void remove_e820_regions(struct resource *avail)
{
int i;
struct e820entry *entry;
for (i = 0; i < e820->nr_map; i++) {
entry = &e820->map[i];
resource_clip(avail, entry->addr,
entry->addr + entry->size - 1);
}
}
void arch_remove_reservations(struct resource *avail)
{
/*
* Trim out BIOS area (high 2MB) and E820 regions. We do not remove
* the low 1MB unconditionally, as this area is needed for some ISA
* cards requiring a memory range, e.g. the i82365 PCMCIA controller.
*/
if (avail->flags & IORESOURCE_MEM) {
resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END);
remove_e820_regions(avail);
}
}