WSL2-Linux-Kernel/arch/ia64/mm/contig.c

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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1998-2003 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
* Stephane Eranian <eranian@hpl.hp.com>
* Copyright (C) 2000, Rohit Seth <rohit.seth@intel.com>
* Copyright (C) 1999 VA Linux Systems
* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
* Copyright (C) 2003 Silicon Graphics, Inc. All rights reserved.
*
* Routines used by ia64 machines with contiguous (or virtually contiguous)
* memory.
*/
#include <linux/bootmem.h>
#include <linux/efi.h>
#include <linux/mm.h>
#include <linux/nmi.h>
#include <linux/swap.h>
#include <asm/meminit.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/mca.h>
#ifdef CONFIG_VIRTUAL_MEM_MAP
static unsigned long max_gap;
#endif
/**
* show_mem - give short summary of memory stats
*
* Shows a simple page count of reserved and used pages in the system.
* For discontig machines, it does this on a per-pgdat basis.
*/
void show_mem(void)
{
int i, total_reserved = 0;
int total_shared = 0, total_cached = 0;
unsigned long total_present = 0;
pg_data_t *pgdat;
printk(KERN_INFO "Mem-info:\n");
show_free_areas();
printk(KERN_INFO "Node memory in pages:\n");
for_each_online_pgdat(pgdat) {
unsigned long present;
unsigned long flags;
int shared = 0, cached = 0, reserved = 0;
pgdat_resize_lock(pgdat, &flags);
present = pgdat->node_present_pages;
for(i = 0; i < pgdat->node_spanned_pages; i++) {
struct page *page;
if (unlikely(i % MAX_ORDER_NR_PAGES == 0))
touch_nmi_watchdog();
if (pfn_valid(pgdat->node_start_pfn + i))
page = pfn_to_page(pgdat->node_start_pfn + i);
else {
#ifdef CONFIG_VIRTUAL_MEM_MAP
if (max_gap < LARGE_GAP)
continue;
#endif
i = vmemmap_find_next_valid_pfn(pgdat->node_id,
i) - 1;
continue;
}
if (PageReserved(page))
reserved++;
else if (PageSwapCache(page))
cached++;
else if (page_count(page))
shared += page_count(page)-1;
}
pgdat_resize_unlock(pgdat, &flags);
total_present += present;
total_reserved += reserved;
total_cached += cached;
total_shared += shared;
printk(KERN_INFO "Node %4d: RAM: %11ld, rsvd: %8d, "
"shrd: %10d, swpd: %10d\n", pgdat->node_id,
present, reserved, shared, cached);
}
printk(KERN_INFO "%ld pages of RAM\n", total_present);
printk(KERN_INFO "%d reserved pages\n", total_reserved);
printk(KERN_INFO "%d pages shared\n", total_shared);
printk(KERN_INFO "%d pages swap cached\n", total_cached);
printk(KERN_INFO "Total of %ld pages in page table cache\n",
quicklist_total_size());
printk(KERN_INFO "%d free buffer pages\n", nr_free_buffer_pages());
}
/* physical address where the bootmem map is located */
unsigned long bootmap_start;
/**
* find_bootmap_location - callback to find a memory area for the bootmap
* @start: start of region
* @end: end of region
* @arg: unused callback data
*
* Find a place to put the bootmap and return its starting address in
* bootmap_start. This address must be page-aligned.
*/
static int __init
find_bootmap_location (unsigned long start, unsigned long end, void *arg)
{
unsigned long needed = *(unsigned long *)arg;
unsigned long range_start, range_end, free_start;
int i;
#if IGNORE_PFN0
if (start == PAGE_OFFSET) {
start += PAGE_SIZE;
if (start >= end)
return 0;
}
#endif
free_start = PAGE_OFFSET;
for (i = 0; i < num_rsvd_regions; i++) {
range_start = max(start, free_start);
range_end = min(end, rsvd_region[i].start & PAGE_MASK);
free_start = PAGE_ALIGN(rsvd_region[i].end);
if (range_end <= range_start)
continue; /* skip over empty range */
if (range_end - range_start >= needed) {
bootmap_start = __pa(range_start);
return -1; /* done */
}
/* nothing more available in this segment */
if (range_end == end)
return 0;
}
return 0;
}
#ifdef CONFIG_SMP
static void *cpu_data;
/**
* per_cpu_init - setup per-cpu variables
*
* Allocate and setup per-cpu data areas.
*/
void * __cpuinit
per_cpu_init (void)
{
int cpu;
static int first_time=1;
/*
* get_free_pages() cannot be used before cpu_init() done. BSP
* allocates "NR_CPUS" pages for all CPUs to avoid that AP calls
* get_zeroed_page().
*/
if (first_time) {
first_time=0;
for (cpu = 0; cpu < NR_CPUS; cpu++) {
memcpy(cpu_data, __phys_per_cpu_start, __per_cpu_end - __per_cpu_start);
__per_cpu_offset[cpu] = (char *) cpu_data - __per_cpu_start;
cpu_data += PERCPU_PAGE_SIZE;
per_cpu(local_per_cpu_offset, cpu) = __per_cpu_offset[cpu];
}
}
return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
}
static inline void
alloc_per_cpu_data(void)
{
cpu_data = __alloc_bootmem(PERCPU_PAGE_SIZE * NR_CPUS,
PERCPU_PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
}
#else
#define alloc_per_cpu_data() do { } while (0)
#endif /* CONFIG_SMP */
/**
* find_memory - setup memory map
*
* Walk the EFI memory map and find usable memory for the system, taking
* into account reserved areas.
*/
void __init
find_memory (void)
{
unsigned long bootmap_size;
reserve_memory();
/* first find highest page frame number */
[IA64] min_low_pfn and max_low_pfn calculation fix We have seen bad_pte_print when testing crashdump on an SN machine in recent 2.6.20 kernel. There are tons of bad pte print (pfn < max_low_pfn) reports when the crash kernel boots up, all those reported bad pages are inside initmem range; That is because if the crash kernel code and data happens to be at the beginning of the 1st node. build_node_maps in discontig.c will bypass reserved regions with filter_rsvd_memory. Since min_low_pfn is calculated in build_node_map, so in this case, min_low_pfn will be greater than kernel code and data. Because pages inside initmem are freed and reused later, we saw pfn_valid check fail on those pages. I think this theoretically happen on a normal kernel. When I check min_low_pfn and max_low_pfn calculation in contig.c and discontig.c. I found more issues than this. 1. min_low_pfn and max_low_pfn calculation is inconsistent between contig.c and discontig.c, min_low_pfn is calculated as the first page number of boot memmap in contig.c (Why? Though this may work at the most of the time, I don't think it is the right logic). It is calculated as the lowest physical memory page number bypass reserved regions in discontig.c. max_low_pfn is calculated include reserved regions in contig.c. It is calculated exclude reserved regions in discontig.c. 2. If kernel code and data region is happen to be at the begin or the end of physical memory, when min_low_pfn and max_low_pfn calculation is bypassed kernel code and data, pages in initmem will report bad. 3. initrd is also in reserved regions, if it is at the begin or at the end of physical memory, kernel will refuse to reuse the memory. Because the virt_addr_valid check in free_initrd_mem. So it is better to fix and clean up those issues. Calculate min_low_pfn and max_low_pfn in a consistent way. Signed-off-by: Zou Nan hai <nanhai.zou@intel.com> Acked-by: Jay Lan <jlan@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-20 23:41:57 +03:00
min_low_pfn = ~0UL;
max_low_pfn = 0;
efi_memmap_walk(find_max_min_low_pfn, NULL);
max_pfn = max_low_pfn;
/* how many bytes to cover all the pages */
bootmap_size = bootmem_bootmap_pages(max_pfn) << PAGE_SHIFT;
/* look for a location to hold the bootmap */
bootmap_start = ~0UL;
efi_memmap_walk(find_bootmap_location, &bootmap_size);
if (bootmap_start == ~0UL)
panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
[IA64] min_low_pfn and max_low_pfn calculation fix We have seen bad_pte_print when testing crashdump on an SN machine in recent 2.6.20 kernel. There are tons of bad pte print (pfn < max_low_pfn) reports when the crash kernel boots up, all those reported bad pages are inside initmem range; That is because if the crash kernel code and data happens to be at the beginning of the 1st node. build_node_maps in discontig.c will bypass reserved regions with filter_rsvd_memory. Since min_low_pfn is calculated in build_node_map, so in this case, min_low_pfn will be greater than kernel code and data. Because pages inside initmem are freed and reused later, we saw pfn_valid check fail on those pages. I think this theoretically happen on a normal kernel. When I check min_low_pfn and max_low_pfn calculation in contig.c and discontig.c. I found more issues than this. 1. min_low_pfn and max_low_pfn calculation is inconsistent between contig.c and discontig.c, min_low_pfn is calculated as the first page number of boot memmap in contig.c (Why? Though this may work at the most of the time, I don't think it is the right logic). It is calculated as the lowest physical memory page number bypass reserved regions in discontig.c. max_low_pfn is calculated include reserved regions in contig.c. It is calculated exclude reserved regions in discontig.c. 2. If kernel code and data region is happen to be at the begin or the end of physical memory, when min_low_pfn and max_low_pfn calculation is bypassed kernel code and data, pages in initmem will report bad. 3. initrd is also in reserved regions, if it is at the begin or at the end of physical memory, kernel will refuse to reuse the memory. Because the virt_addr_valid check in free_initrd_mem. So it is better to fix and clean up those issues. Calculate min_low_pfn and max_low_pfn in a consistent way. Signed-off-by: Zou Nan hai <nanhai.zou@intel.com> Acked-by: Jay Lan <jlan@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-20 23:41:57 +03:00
bootmap_size = init_bootmem_node(NODE_DATA(0),
(bootmap_start >> PAGE_SHIFT), 0, max_pfn);
/* Free all available memory, then mark bootmem-map as being in use. */
efi_memmap_walk(filter_rsvd_memory, free_bootmem);
reserve_bootmem(bootmap_start, bootmap_size, BOOTMEM_DEFAULT);
find_initrd();
alloc_per_cpu_data();
}
static int
count_pages (u64 start, u64 end, void *arg)
{
unsigned long *count = arg;
*count += (end - start) >> PAGE_SHIFT;
return 0;
}
/*
* Set up the page tables.
*/
void __init
paging_init (void)
{
unsigned long max_dma;
unsigned long max_zone_pfns[MAX_NR_ZONES];
num_physpages = 0;
efi_memmap_walk(count_pages, &num_physpages);
memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
#ifdef CONFIG_ZONE_DMA
max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
max_zone_pfns[ZONE_DMA] = max_dma;
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
#ifdef CONFIG_VIRTUAL_MEM_MAP
efi_memmap_walk(filter_memory, register_active_ranges);
efi_memmap_walk(find_largest_hole, (u64 *)&max_gap);
if (max_gap < LARGE_GAP) {
vmem_map = (struct page *) 0;
free_area_init_nodes(max_zone_pfns);
} else {
unsigned long map_size;
/* allocate virtual_mem_map */
map_size = PAGE_ALIGN(ALIGN(max_low_pfn, MAX_ORDER_NR_PAGES) *
sizeof(struct page));
vmalloc_end -= map_size;
vmem_map = (struct page *) vmalloc_end;
efi_memmap_walk(create_mem_map_page_table, NULL);
/*
* alloc_node_mem_map makes an adjustment for mem_map
* which isn't compatible with vmem_map.
*/
NODE_DATA(0)->node_mem_map = vmem_map +
find_min_pfn_with_active_regions();
free_area_init_nodes(max_zone_pfns);
printk("Virtual mem_map starts at 0x%p\n", mem_map);
}
#else /* !CONFIG_VIRTUAL_MEM_MAP */
add_active_range(0, 0, max_low_pfn);
free_area_init_nodes(max_zone_pfns);
#endif /* !CONFIG_VIRTUAL_MEM_MAP */
zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
}