kernel-fxtec-pro1x/arch/ia64/mm/contig.c
Tony Luck 10617bbe84 [IA64] Ensure cpu0 can access per-cpu variables in early boot code
ia64 handles per-cpu variables a litle differently from other architectures
in that it maps the physical memory allocated for each cpu at a constant
virtual address (0xffffffffffff0000). This mapping is not enabled until
the architecture specific cpu_init() function is run, which causes problems
since some generic code is run before this point. In particular when
CONFIG_PRINTK_TIME is enabled, the boot cpu will trap on the access to
per-cpu memory at the first printk() call so the boot will fail without
the kernel printing anything to the console.

Fix this by allocating percpu memory for cpu0 in the kernel data section
and doing all initialization to enable percpu access in head.S before
calling any generic code.

Other cpus must take care not to access per-cpu variables too early, but
their code path from start_secondary() to cpu_init() is all in arch/ia64

Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-08-12 10:34:20 -07:00

293 lines
7.7 KiB
C

/*
* 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) {
void *cpu0_data = __phys_per_cpu_start - PERCPU_PAGE_SIZE;
first_time=0;
__per_cpu_offset[0] = (char *) cpu0_data - __per_cpu_start;
per_cpu(local_per_cpu_offset, 0) = __per_cpu_offset[0];
for (cpu = 1; 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-1,
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 */
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);
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));
}