kernel-fxtec-pro1x/arch/s390/mm/vmem.c
Heiko Carstens 0189103c69 [S390] Remove BUILD_BUG_ON() in vmem code.
Remove BUILD_BUG_ON() in vmem code since it causes build failures if
the size of struct page increases. Instead calculate at compile time
the address of the highest physical address that can be added to the
1:1 mapping.
This supposed to fix a build failure with the page owner tracking leak
detector patches as reported by akpm.

page-owner-tracking-leak-detector-broken-on-s390.patch can be removed
from -mm again when this is merged.

Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-05 16:51:01 +01:00

392 lines
8.4 KiB
C

/*
* arch/s390/mm/vmem.c
*
* Copyright IBM Corp. 2006
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
*/
#include <linux/bootmem.h>
#include <linux/pfn.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/list.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/setup.h>
#include <asm/tlbflush.h>
static DEFINE_MUTEX(vmem_mutex);
struct memory_segment {
struct list_head list;
unsigned long start;
unsigned long size;
};
static LIST_HEAD(mem_segs);
void __meminit memmap_init(unsigned long size, int nid, unsigned long zone,
unsigned long start_pfn)
{
struct page *start, *end;
struct page *map_start, *map_end;
int i;
start = pfn_to_page(start_pfn);
end = start + size;
for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
unsigned long cstart, cend;
cstart = PFN_DOWN(memory_chunk[i].addr);
cend = cstart + PFN_DOWN(memory_chunk[i].size);
map_start = mem_map + cstart;
map_end = mem_map + cend;
if (map_start < start)
map_start = start;
if (map_end > end)
map_end = end;
map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1))
/ sizeof(struct page);
map_end += ((PFN_ALIGN((unsigned long) map_end)
- (unsigned long) map_end)
/ sizeof(struct page));
if (map_start < map_end)
memmap_init_zone((unsigned long)(map_end - map_start),
nid, zone, page_to_pfn(map_start),
MEMMAP_EARLY);
}
}
static void __ref *vmem_alloc_pages(unsigned int order)
{
if (slab_is_available())
return (void *)__get_free_pages(GFP_KERNEL, order);
return alloc_bootmem_pages((1 << order) * PAGE_SIZE);
}
#define vmem_pud_alloc() ({ BUG(); ((pud_t *) NULL); })
static inline pmd_t *vmem_pmd_alloc(void)
{
pmd_t *pmd = NULL;
#ifdef CONFIG_64BIT
pmd = vmem_alloc_pages(2);
if (!pmd)
return NULL;
clear_table((unsigned long *) pmd, _SEGMENT_ENTRY_EMPTY, PAGE_SIZE*4);
#endif
return pmd;
}
static inline pte_t *vmem_pte_alloc(void)
{
pte_t *pte = vmem_alloc_pages(0);
if (!pte)
return NULL;
clear_table((unsigned long *) pte, _PAGE_TYPE_EMPTY, PAGE_SIZE);
return pte;
}
/*
* Add a physical memory range to the 1:1 mapping.
*/
static int vmem_add_range(unsigned long start, unsigned long size)
{
unsigned long address;
pgd_t *pg_dir;
pud_t *pu_dir;
pmd_t *pm_dir;
pte_t *pt_dir;
pte_t pte;
int ret = -ENOMEM;
for (address = start; address < start + size; address += PAGE_SIZE) {
pg_dir = pgd_offset_k(address);
if (pgd_none(*pg_dir)) {
pu_dir = vmem_pud_alloc();
if (!pu_dir)
goto out;
pgd_populate_kernel(&init_mm, pg_dir, pu_dir);
}
pu_dir = pud_offset(pg_dir, address);
if (pud_none(*pu_dir)) {
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
goto out;
pud_populate_kernel(&init_mm, pu_dir, pm_dir);
}
pm_dir = pmd_offset(pu_dir, address);
if (pmd_none(*pm_dir)) {
pt_dir = vmem_pte_alloc();
if (!pt_dir)
goto out;
pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
}
pt_dir = pte_offset_kernel(pm_dir, address);
pte = pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL);
*pt_dir = pte;
}
ret = 0;
out:
flush_tlb_kernel_range(start, start + size);
return ret;
}
/*
* Remove a physical memory range from the 1:1 mapping.
* Currently only invalidates page table entries.
*/
static void vmem_remove_range(unsigned long start, unsigned long size)
{
unsigned long address;
pgd_t *pg_dir;
pud_t *pu_dir;
pmd_t *pm_dir;
pte_t *pt_dir;
pte_t pte;
pte_val(pte) = _PAGE_TYPE_EMPTY;
for (address = start; address < start + size; address += PAGE_SIZE) {
pg_dir = pgd_offset_k(address);
pu_dir = pud_offset(pg_dir, address);
if (pud_none(*pu_dir))
continue;
pm_dir = pmd_offset(pu_dir, address);
if (pmd_none(*pm_dir))
continue;
pt_dir = pte_offset_kernel(pm_dir, address);
*pt_dir = pte;
}
flush_tlb_kernel_range(start, start + size);
}
/*
* Add a backed mem_map array to the virtual mem_map array.
*/
static int vmem_add_mem_map(unsigned long start, unsigned long size)
{
unsigned long address, start_addr, end_addr;
struct page *map_start, *map_end;
pgd_t *pg_dir;
pud_t *pu_dir;
pmd_t *pm_dir;
pte_t *pt_dir;
pte_t pte;
int ret = -ENOMEM;
map_start = VMEM_MAP + PFN_DOWN(start);
map_end = VMEM_MAP + PFN_DOWN(start + size);
start_addr = (unsigned long) map_start & PAGE_MASK;
end_addr = PFN_ALIGN((unsigned long) map_end);
for (address = start_addr; address < end_addr; address += PAGE_SIZE) {
pg_dir = pgd_offset_k(address);
if (pgd_none(*pg_dir)) {
pu_dir = vmem_pud_alloc();
if (!pu_dir)
goto out;
pgd_populate_kernel(&init_mm, pg_dir, pu_dir);
}
pu_dir = pud_offset(pg_dir, address);
if (pud_none(*pu_dir)) {
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
goto out;
pud_populate_kernel(&init_mm, pu_dir, pm_dir);
}
pm_dir = pmd_offset(pu_dir, address);
if (pmd_none(*pm_dir)) {
pt_dir = vmem_pte_alloc();
if (!pt_dir)
goto out;
pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
}
pt_dir = pte_offset_kernel(pm_dir, address);
if (pte_none(*pt_dir)) {
unsigned long new_page;
new_page =__pa(vmem_alloc_pages(0));
if (!new_page)
goto out;
pte = pfn_pte(new_page >> PAGE_SHIFT, PAGE_KERNEL);
*pt_dir = pte;
}
}
ret = 0;
out:
flush_tlb_kernel_range(start_addr, end_addr);
return ret;
}
static int vmem_add_mem(unsigned long start, unsigned long size)
{
int ret;
ret = vmem_add_mem_map(start, size);
if (ret)
return ret;
return vmem_add_range(start, size);
}
/*
* Add memory segment to the segment list if it doesn't overlap with
* an already present segment.
*/
static int insert_memory_segment(struct memory_segment *seg)
{
struct memory_segment *tmp;
if (seg->start + seg->size >= VMEM_MAX_PHYS ||
seg->start + seg->size < seg->start)
return -ERANGE;
list_for_each_entry(tmp, &mem_segs, list) {
if (seg->start >= tmp->start + tmp->size)
continue;
if (seg->start + seg->size <= tmp->start)
continue;
return -ENOSPC;
}
list_add(&seg->list, &mem_segs);
return 0;
}
/*
* Remove memory segment from the segment list.
*/
static void remove_memory_segment(struct memory_segment *seg)
{
list_del(&seg->list);
}
static void __remove_shared_memory(struct memory_segment *seg)
{
remove_memory_segment(seg);
vmem_remove_range(seg->start, seg->size);
}
int remove_shared_memory(unsigned long start, unsigned long size)
{
struct memory_segment *seg;
int ret;
mutex_lock(&vmem_mutex);
ret = -ENOENT;
list_for_each_entry(seg, &mem_segs, list) {
if (seg->start == start && seg->size == size)
break;
}
if (seg->start != start || seg->size != size)
goto out;
ret = 0;
__remove_shared_memory(seg);
kfree(seg);
out:
mutex_unlock(&vmem_mutex);
return ret;
}
int add_shared_memory(unsigned long start, unsigned long size)
{
struct memory_segment *seg;
struct page *page;
unsigned long pfn, num_pfn, end_pfn;
int ret;
mutex_lock(&vmem_mutex);
ret = -ENOMEM;
seg = kzalloc(sizeof(*seg), GFP_KERNEL);
if (!seg)
goto out;
seg->start = start;
seg->size = size;
ret = insert_memory_segment(seg);
if (ret)
goto out_free;
ret = vmem_add_mem(start, size);
if (ret)
goto out_remove;
pfn = PFN_DOWN(start);
num_pfn = PFN_DOWN(size);
end_pfn = pfn + num_pfn;
page = pfn_to_page(pfn);
memset(page, 0, num_pfn * sizeof(struct page));
for (; pfn < end_pfn; pfn++) {
page = pfn_to_page(pfn);
init_page_count(page);
reset_page_mapcount(page);
SetPageReserved(page);
INIT_LIST_HEAD(&page->lru);
}
goto out;
out_remove:
__remove_shared_memory(seg);
out_free:
kfree(seg);
out:
mutex_unlock(&vmem_mutex);
return ret;
}
/*
* map whole physical memory to virtual memory (identity mapping)
* we reserve enough space in the vmalloc area for vmemmap to hotplug
* additional memory segments.
*/
void __init vmem_map_init(void)
{
int i;
NODE_DATA(0)->node_mem_map = VMEM_MAP;
for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++)
vmem_add_mem(memory_chunk[i].addr, memory_chunk[i].size);
}
/*
* Convert memory chunk array to a memory segment list so there is a single
* list that contains both r/w memory and shared memory segments.
*/
static int __init vmem_convert_memory_chunk(void)
{
struct memory_segment *seg;
int i;
mutex_lock(&vmem_mutex);
for (i = 0; i < MEMORY_CHUNKS; i++) {
if (!memory_chunk[i].size)
continue;
seg = kzalloc(sizeof(*seg), GFP_KERNEL);
if (!seg)
panic("Out of memory...\n");
seg->start = memory_chunk[i].addr;
seg->size = memory_chunk[i].size;
insert_memory_segment(seg);
}
mutex_unlock(&vmem_mutex);
return 0;
}
core_initcall(vmem_convert_memory_chunk);