/*
* Initialize MMU support.
*
* Copyright (C) 1998-2003 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/efi.h>
#include <linux/elf.h>
#include <linux/memblock.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/proc_fs.h>
#include <linux/bitops.h>
#include <linux/kexec.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/machvec.h>
#include <asm/numa.h>
#include <asm/patch.h>
#include <asm/pgalloc.h>
#include <asm/sal.h>
#include <asm/sections.h>
#include <asm/tlb.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <asm/mca.h>
#include <asm/paravirt.h>
extern void ia64_tlb_init (void);
unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
#ifdef CONFIG_VIRTUAL_MEM_MAP
unsigned long VMALLOC_END = VMALLOC_END_INIT;
EXPORT_SYMBOL(VMALLOC_END);
struct page *vmem_map;
EXPORT_SYMBOL(vmem_map);
#endif
struct page *zero_page_memmap_ptr; /* map entry for zero page */
EXPORT_SYMBOL(zero_page_memmap_ptr);
void
__ia64_sync_icache_dcache (pte_t pte)
{
unsigned long addr;
struct page *page;
page = pte_page(pte);
addr = (unsigned long) page_address(page);
if (test_bit(PG_arch_1, &page->flags))
return; /* i-cache is already coherent with d-cache */
flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page)));
set_bit(PG_arch_1, &page->flags); /* mark page as clean */
}
/*
* Since DMA is i-cache coherent, any (complete) pages that were written via
* DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
* flush them when they get mapped into an executable vm-area.
*/
void
dma_mark_clean(void *addr, size_t size)
{
unsigned long pg_addr, end;
pg_addr = PAGE_ALIGN((unsigned long) addr);
end = (unsigned long) addr + size;
while (pg_addr + PAGE_SIZE <= end) {
struct page *page = virt_to_page(pg_addr);
set_bit(PG_arch_1, &page->flags);
pg_addr += PAGE_SIZE;
}
}
inline void
ia64_set_rbs_bot (void)
{
unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16;
if (stack_size > MAX_USER_STACK_SIZE)
stack_size = MAX_USER_STACK_SIZE;
current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size);
}
/*
* This performs some platform-dependent address space initialization.
* On IA-64, we want to setup the VM area for the register backing
* store (which grows upwards) and install the gateway page which is
* used for signal trampolines, etc.
*/
void
ia64_init_addr_space (void)
{
struct vm_area_struct *vma;
ia64_set_rbs_bot();
/*
* If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
* the problem. When the process attempts to write to the register backing store
* for the first time, it will get a SEGFAULT in this case.
*/
vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
if (vma) {
INIT_LIST_HEAD(&vma->anon_vma_chain);
vma->vm_mm = current->mm;
vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
vma->vm_end = vma->vm_start + PAGE_SIZE;
vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
down_write(¤t->mm->mmap_sem);
if (insert_vm_struct(current->mm, vma)) {
up_write(¤t->mm->mmap_sem);
kmem_cache_free(vm_area_cachep, vma);
return;
}
up_write(¤t->mm->mmap_sem);
}
/* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
if (!(current->personality & MMAP_PAGE_ZERO)) {
vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
if (vma) {
INIT_LIST_HEAD(&vma->anon_vma_chain);
vma->vm_mm = current->mm;
vma->vm_end = PAGE_SIZE;
vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO |
VM_DONTEXPAND | VM_DONTDUMP;
down_write(¤t->mm->mmap_sem);
if (insert_vm_struct(current->mm, vma)) {
up_write(¤t->mm->mmap_sem);
kmem_cache_free(vm_area_cachep, vma);
return;
}
up_write(¤t->mm->mmap_sem);
}
}
}
void
free_initmem (void)
{
free_reserved_area((unsigned long)ia64_imva(__init_begin),
(unsigned long)ia64_imva(__init_end),
0, "unused kernel");
}
void __init
free_initrd_mem (unsigned long start, unsigned long end)
{
/*
* EFI uses 4KB pages while the kernel can use 4KB or bigger.
* Thus EFI and the kernel may have different page sizes. It is
* therefore possible to have the initrd share the same page as
* the end of the kernel (given current setup).
*
* To avoid freeing/using the wrong page (kernel sized) we:
* - align up the beginning of initrd
* - align down the end of initrd
*
* | |
* |=============| a000
* | |
* | |
* | | 9000
* |/////////////|
* |/////////////|
* |=============| 8000
* |///INITRD////|
* |/////////////|
* |/////////////| 7000
* | |
* |KKKKKKKKKKKKK|
* |=============| 6000
* |KKKKKKKKKKKKK|
* |KKKKKKKKKKKKK|
* K=kernel using 8KB pages
*
* In this example, we must free page 8000 ONLY. So we must align up
* initrd_start and keep initrd_end as is.
*/
start = PAGE_ALIGN(start);
end = end & PAGE_MASK;
if (start < end)
printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
for (; start < end; start += PAGE_SIZE) {
if (!virt_addr_valid(start))
continue;
free_reserved_page(virt_to_page(start));
}
}
/*
* This installs a clean page in the kernel's page table.
*/
static struct page * __init
put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
if (!PageReserved(page))
printk(KERN_ERR "put_kernel_page: page at 0x%p not in reserved memory\n",
page_address(page));
pgd = pgd_offset_k(address); /* note: this is NOT pgd_offset()! */
{
pud = pud_alloc(&init_mm, pgd, address);
if (!pud)
goto out;
pmd = pmd_alloc(&init_mm, pud, address);
if (!pmd)
goto out;
pte = pte_alloc_kernel(pmd, address);
if (!pte)
goto out;
if (!pte_none(*pte))
goto out;
set_pte(pte, mk_pte(page, pgprot));
}
out:
/* no need for flush_tlb */
return page;
}
static void __init
setup_gate (void)
{
void *gate_section;
struct page *page;
/*
* Map the gate page twice: once read-only to export the ELF
* headers etc. and once execute-only page to enable
* privilege-promotion via "epc":
*/
gate_section = paravirt_get_gate_section();
page = virt_to_page(ia64_imva(gate_section));
put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
#ifdef HAVE_BUGGY_SEGREL
page = virt_to_page(ia64_imva(gate_section + PAGE_SIZE));
put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
#else
put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
/* Fill in the holes (if any) with read-only zero pages: */
{
unsigned long addr;
for (addr = GATE_ADDR + PAGE_SIZE;
addr < GATE_ADDR + PERCPU_PAGE_SIZE;
addr += PAGE_SIZE)
{
put_kernel_page(ZERO_PAGE(0), addr,
PAGE_READONLY);
put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
PAGE_READONLY);
}
}
#endif
ia64_patch_gate();
}
void ia64_mmu_init(void *my_cpu_data)
{
unsigned long pta, impl_va_bits;
extern void tlb_init(void);
#ifdef CONFIG_DISABLE_VHPT
# define VHPT_ENABLE_BIT 0
#else
# define VHPT_ENABLE_BIT 1
#endif
/*
* Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
* address space. The IA-64 architecture guarantees that at least 50 bits of
* virtual address space are implemented but if we pick a large enough page size
* (e.g., 64KB), the mapped address space is big enough that it will overlap with
* VMLPT. I assume that once we run on machines big enough to warrant 64KB pages,
* IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
* problem in practice. Alternatively, we could truncate the top of the mapped
* address space to not permit mappings that would overlap with the VMLPT.
* --davidm 00/12/06
*/
# define pte_bits 3
# define mapped_space_bits (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
/*
* The virtual page table has to cover the entire implemented address space within
* a region even though not all of this space may be mappable. The reason for
* this is that the Access bit and Dirty bit fault handlers perform
* non-speculative accesses to the virtual page table, so the address range of the
* virtual page table itself needs to be covered by virtual page table.
*/
# define vmlpt_bits (impl_va_bits - PAGE_SHIFT + pte_bits)
# define POW2(n) (1ULL << (n))
impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
if (impl_va_bits < 51 || impl_va_bits > 61)
panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
/*
* mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
* which must fit into "vmlpt_bits - pte_bits" slots. Second half of
* the test makes sure that our mapped space doesn't overlap the
* unimplemented hole in the middle of the region.
*/
if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
(mapped_space_bits > impl_va_bits - 1))
panic("Cannot build a big enough virtual-linear page table"
" to cover mapped address space.\n"
" Try using a smaller page size.\n");
/* place the VMLPT at the end of each page-table mapped region: */
pta = POW2(61) - POW2(vmlpt_bits);
/*
* Set the (virtually mapped linear) page table address. Bit
* 8 selects between the short and long format, bits 2-7 the
* size of the table, and bit 0 whether the VHPT walker is
* enabled.
*/
ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
ia64_tlb_init();
#ifdef CONFIG_HUGETLB_PAGE
ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
ia64_srlz_d();
#endif
}
#ifdef CONFIG_VIRTUAL_MEM_MAP
int vmemmap_find_next_valid_pfn(int node, int i)
{
unsigned long end_address, hole_next_pfn;
unsigned long stop_address;
pg_data_t *pgdat = NODE_DATA(node);
end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
end_address = PAGE_ALIGN(end_address);
stop_address = (unsigned long) &vmem_map[
pgdat->node_start_pfn + pgdat->node_spanned_pages];
do {
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
pgd = pgd_offset_k(end_address);
if (pgd_none(*pgd)) {
end_address += PGDIR_SIZE;
continue;
}
pud = pud_offset(pgd, end_address);
if (pud_none(*pud)) {
end_address += PUD_SIZE;
continue;
}
pmd = pmd_offset(pud, end_address);
if (pmd_none(*pmd)) {
end_address += PMD_SIZE;
continue;
}
pte = pte_offset_kernel(pmd, end_address);
retry_pte:
if (pte_none(*pte)) {
end_address += PAGE_SIZE;
pte++;
if ((end_address < stop_address) &&
(end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
goto retry_pte;
continue;
}
/* Found next valid vmem_map page */
break;
} while (end_address < stop_address);
end_address = min(end_address, stop_address);
end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
hole_next_pfn = end_address / sizeof(struct page);
return hole_next_pfn - pgdat->node_start_pfn;
}
int __init create_mem_map_page_table(u64 start, u64 end, void *arg)
{
unsigned long address, start_page, end_page;
struct page *map_start, *map_end;
int node;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
map_end = vmem_map + (__pa(end) >> PAGE_SHIFT);
start_page = (unsigned long) map_start & PAGE_MASK;
end_page = PAGE_ALIGN((unsigned long) map_end);
node = paddr_to_nid(__pa(start));
for (address = start_page; address < end_page; address += PAGE_SIZE) {
pgd = pgd_offset_k(address);
if (pgd_none(*pgd))
pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
pud = pud_offset(pgd, address);
if (pud_none(*pud))
pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
pmd = pmd_offset(pud, address);
if (pmd_none(*pmd))
pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
pte = pte_offset_kernel(pmd, address);
if (pte_none(*pte))
set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
PAGE_KERNEL));
}
return 0;
}
struct memmap_init_callback_data {
struct page *start;
struct page *end;
int nid;
unsigned long zone;
};
static int __meminit
virtual_memmap_init(u64 start, u64 end, void *arg)
{
struct memmap_init_callback_data *args;
struct page *map_start, *map_end;
args = (struct memmap_init_callback_data *) arg;
map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
map_end = vmem_map + (__pa(end) >> PAGE_SHIFT);
if (map_start < args->start)
map_start = args->start;
if (map_end > args->end)
map_end = args->end;
/*
* We have to initialize "out of bounds" struct page elements that fit completely
* on the same pages that were allocated for the "in bounds" elements because they
* may be referenced later (and found to be "reserved").
*/
map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
map_end += ((PAGE_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),
args->nid, args->zone, page_to_pfn(map_start),
MEMMAP_EARLY);
return 0;
}
void __meminit
memmap_init (unsigned long size, int nid, unsigned long zone,
unsigned long start_pfn)
{
if (!vmem_map)
memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
else {
struct page *start;
struct memmap_init_callback_data args;
start = pfn_to_page(start_pfn);
args.start = start;
args.end = start + size;
args.nid = nid;
args.zone = zone;
efi_memmap_walk(virtual_memmap_init, &args);
}
}
int
ia64_pfn_valid (unsigned long pfn)
{
char byte;
struct page *pg = pfn_to_page(pfn);
return (__get_user(byte, (char __user *) pg) == 0)
&& ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
|| (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
}
EXPORT_SYMBOL(ia64_pfn_valid);
int __init find_largest_hole(u64 start, u64 end, void *arg)
{
u64 *max_gap = arg;
static u64 last_end = PAGE_OFFSET;
/* NOTE: this algorithm assumes efi memmap table is ordered */
if (*max_gap < (start - last_end))
*max_gap = start - last_end;
last_end = end;
return 0;
}
#endif /* CONFIG_VIRTUAL_MEM_MAP */
int __init register_active_ranges(u64 start, u64 len, int nid)
{
u64 end = start + len;
#ifdef CONFIG_KEXEC
if (start > crashk_res.start && start < crashk_res.end)
start = crashk_res.end;
if (end > crashk_res.start && end < crashk_res.end)
end = crashk_res.start;
#endif
if (start < end)
memblock_add_node(__pa(start), end - start, nid);
return 0;
}
static int __init
count_reserved_pages(u64 start, u64 end, void *arg)
{
unsigned long num_reserved = 0;
unsigned long *count = arg;
for (; start < end; start += PAGE_SIZE)
if (PageReserved(virt_to_page(start)))
++num_reserved;
*count += num_reserved;
return 0;
}
int
find_max_min_low_pfn (u64 start, u64 end, void *arg)
{
unsigned long pfn_start, pfn_end;
#ifdef CONFIG_FLATMEM
pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT;
pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT;
#else
pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT;
pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT;
#endif
min_low_pfn = min(min_low_pfn, pfn_start);
max_low_pfn = max(max_low_pfn, pfn_end);
return 0;
}
/*
* Boot command-line option "nolwsys" can be used to disable the use of any light-weight
* system call handler. When this option is in effect, all fsyscalls will end up bubbling
* down into the kernel and calling the normal (heavy-weight) syscall handler. This is
* useful for performance testing, but conceivably could also come in handy for debugging
* purposes.
*/
static int nolwsys __initdata;
static int __init
nolwsys_setup (char *s)
{
nolwsys = 1;
return 1;
}
__setup("nolwsys", nolwsys_setup);
void __init
mem_init (void)
{
long reserved_pages, codesize, datasize, initsize;
pg_data_t *pgdat;
int i;
BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);
#ifdef CONFIG_PCI
/*
* This needs to be called _after_ the command line has been parsed but _before_
* any drivers that may need the PCI DMA interface are initialized or bootmem has
* been freed.
*/
platform_dma_init();
#endif
#ifdef CONFIG_FLATMEM
BUG_ON(!mem_map);
max_mapnr = max_low_pfn;
#endif
high_memory = __va(max_low_pfn * PAGE_SIZE);
for_each_online_pgdat(pgdat)
if (pgdat->bdata->node_bootmem_map)
totalram_pages += free_all_bootmem_node(pgdat);
reserved_pages = 0;
efi_memmap_walk(count_reserved_pages, &reserved_pages);
codesize = (unsigned long) _etext - (unsigned long) _stext;
datasize = (unsigned long) _edata - (unsigned long) _etext;
initsize = (unsigned long) __init_end - (unsigned long) __init_begin;
printk(KERN_INFO "Memory: %luk/%luk available (%luk code, %luk reserved, "
"%luk data, %luk init)\n", nr_free_pages() << (PAGE_SHIFT - 10),
num_physpages << (PAGE_SHIFT - 10), codesize >> 10,
reserved_pages << (PAGE_SHIFT - 10), datasize >> 10, initsize >> 10);
/*
* For fsyscall entrpoints with no light-weight handler, use the ordinary
* (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
* code can tell them apart.
*/
for (i = 0; i < NR_syscalls; ++i) {
extern unsigned long sys_call_table[NR_syscalls];
unsigned long *fsyscall_table = paravirt_get_fsyscall_table();
if (!fsyscall_table[i] || nolwsys)
fsyscall_table[i] = sys_call_table[i] | 1;
}
setup_gate();
}
#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size)
{
pg_data_t *pgdat;
struct zone *zone;
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
int ret;
pgdat = NODE_DATA(nid);
zone = pgdat->node_zones + ZONE_NORMAL;
ret = __add_pages(nid, zone, start_pfn, nr_pages);
if (ret)
printk("%s: Problem encountered in __add_pages() as ret=%d\n",
__func__, ret);
return ret;
}
#ifdef CONFIG_MEMORY_HOTREMOVE
int arch_remove_memory(u64 start, u64 size)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
struct zone *zone;
int ret;
zone = page_zone(pfn_to_page(start_pfn));
ret = __remove_pages(zone, start_pfn, nr_pages);
if (ret)
pr_warn("%s: Problem encountered in __remove_pages() as"
" ret=%d\n", __func__, ret);
return ret;
}
#endif
#endif
/*
* Even when CONFIG_IA32_SUPPORT is not enabled it is
* useful to have the Linux/x86 domain registered to
* avoid an attempted module load when emulators call
* personality(PER_LINUX32). This saves several milliseconds
* on each such call.
*/
static struct exec_domain ia32_exec_domain;
static int __init
per_linux32_init(void)
{
ia32_exec_domain.name = "Linux/x86";
ia32_exec_domain.handler = NULL;
ia32_exec_domain.pers_low = PER_LINUX32;
ia32_exec_domain.pers_high = PER_LINUX32;
ia32_exec_domain.signal_map = default_exec_domain.signal_map;
ia32_exec_domain.signal_invmap = default_exec_domain.signal_invmap;
register_exec_domain(&ia32_exec_domain);
return 0;
}
__initcall(per_linux32_init);