[PATCH] powerpc: mark pages that don't exist as nosave
From: Johannes Berg <johannes@sipsolutions.net>
Date: 2007-05-03 12:28:30
On some powerpc architectures (notably 64-bit powermac) there is a memory hole, for example on powermacs between 2G and 4G. Since we use the flat memory model regardless, these pages must be marked as nosave (for suspend to disk.) Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rafael J. Wysocki <redacted> --- Tested on powerbook and G5 powermac. --- arch/powerpc/mm/mem.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)
--- wireless-dev.orig/arch/powerpc/mm/mem.c 2007-05-03 14:20:25.959165535 +0200
+++ wireless-dev/arch/powerpc/mm/mem.c 2007-05-03 14:21:09.659165535 +0200@@ -31,6 +31,7 @@ #include <linux/highmem.h> #include <linux/initrd.h> #include <linux/pagemap.h> +#include <linux/suspend.h> #include <asm/pgalloc.h> #include <asm/prom.h>
@@ -277,6 +278,28 @@ void __init do_init_bootmem(void) init_bootmem_done = 1; } +/* mark pages that don't exist as nosave */ +static int __init mark_nonram_nosave(void) +{ + unsigned long lmb_next_region_start_pfn, + lmb_region_max_pfn; + int i; + + for (i = 0; i < lmb.memory.cnt - 1; i++) { + lmb_region_max_pfn = + (lmb.memory.region[i].base >> PAGE_SHIFT) + + (lmb.memory.region[i].size >> PAGE_SHIFT); + lmb_next_region_start_pfn = + lmb.memory.region[i+1].base >> PAGE_SHIFT; + + if (lmb_region_max_pfn < lmb_next_region_start_pfn) + register_nosave_region(lmb_region_max_pfn, + lmb_next_region_start_pfn); + } + + return 0; +} + /* * paging_init() sets up the page tables - in fact we've already done this. */
@@ -308,6 +331,8 @@ void __init paging_init(void) max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; #endif free_area_init_nodes(max_zone_pfns); + + mark_nonram_nosave(); } #endif /* ! CONFIG_NEED_MULTIPLE_NODES */