kernel-ark/arch/x86/mm/highmem_32.c
Linus Torvalds 69def9f05d Merge branch 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (202 commits)
  MAINTAINERS: update KVM entry
  KVM: correct error-handling code
  KVM: fix compile warnings on s390
  KVM: VMX: Check cpl before emulating debug register access
  KVM: fix misreporting of coalesced interrupts by kvm tracer
  KVM: x86: drop duplicate kvm_flush_remote_tlb calls
  KVM: VMX: call vmx_load_host_state() only if msr is cached
  KVM: VMX: Conditionally reload debug register 6
  KVM: Use thread debug register storage instead of kvm specific data
  KVM guest: do not batch pte updates from interrupt context
  KVM: Fix coalesced interrupt reporting in IOAPIC
  KVM guest: fix bogus wallclock physical address calculation
  KVM: VMX: Fix cr8 exiting control clobbering by EPT
  KVM: Optimize kvm_mmu_unprotect_page_virt() for tdp
  KVM: Document KVM_CAP_IRQCHIP
  KVM: Protect update_cr8_intercept() when running without an apic
  KVM: VMX: Fix EPT with WP bit change during paging
  KVM: Use kvm_{read,write}_guest_virt() to read and write segment descriptors
  KVM: x86 emulator: Add adc and sbb missing decoder flags
  KVM: Add missing #include
  ...
2009-09-14 17:43:43 -07:00

132 lines
3.2 KiB
C

#include <linux/highmem.h>
#include <linux/module.h>
#include <linux/swap.h> /* for totalram_pages */
void *kmap(struct page *page)
{
might_sleep();
if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
}
void kunmap(struct page *page)
{
if (in_interrupt())
BUG();
if (!PageHighMem(page))
return;
kunmap_high(page);
}
/*
* kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
* no global lock is needed and because the kmap code must perform a global TLB
* invalidation when the kmap pool wraps.
*
* However when holding an atomic kmap it is not legal to sleep, so atomic
* kmaps are appropriate for short, tight code paths only.
*/
void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
{
enum fixed_addresses idx;
unsigned long vaddr;
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
pagefault_disable();
if (!PageHighMem(page))
return page_address(page);
debug_kmap_atomic(type);
idx = type + KM_TYPE_NR*smp_processor_id();
vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
BUG_ON(!pte_none(*(kmap_pte-idx)));
set_pte(kmap_pte-idx, mk_pte(page, prot));
return (void *)vaddr;
}
void *kmap_atomic(struct page *page, enum km_type type)
{
return kmap_atomic_prot(page, type, kmap_prot);
}
void kunmap_atomic(void *kvaddr, enum km_type type)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id();
/*
* Force other mappings to Oops if they'll try to access this pte
* without first remap it. Keeping stale mappings around is a bad idea
* also, in case the page changes cacheability attributes or becomes
* a protected page in a hypervisor.
*/
if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
kpte_clear_flush(kmap_pte-idx, vaddr);
else {
#ifdef CONFIG_DEBUG_HIGHMEM
BUG_ON(vaddr < PAGE_OFFSET);
BUG_ON(vaddr >= (unsigned long)high_memory);
#endif
}
pagefault_enable();
}
/*
* This is the same as kmap_atomic() but can map memory that doesn't
* have a struct page associated with it.
*/
void *kmap_atomic_pfn(unsigned long pfn, enum km_type type)
{
return kmap_atomic_prot_pfn(pfn, type, kmap_prot);
}
EXPORT_SYMBOL_GPL(kmap_atomic_pfn); /* temporarily in use by i915 GEM until vmap */
struct page *kmap_atomic_to_page(void *ptr)
{
unsigned long idx, vaddr = (unsigned long)ptr;
pte_t *pte;
if (vaddr < FIXADDR_START)
return virt_to_page(ptr);
idx = virt_to_fix(vaddr);
pte = kmap_pte - (idx - FIX_KMAP_BEGIN);
return pte_page(*pte);
}
EXPORT_SYMBOL(kmap);
EXPORT_SYMBOL(kunmap);
EXPORT_SYMBOL(kmap_atomic);
EXPORT_SYMBOL(kunmap_atomic);
EXPORT_SYMBOL(kmap_atomic_prot);
EXPORT_SYMBOL(kmap_atomic_to_page);
void __init set_highmem_pages_init(void)
{
struct zone *zone;
int nid;
for_each_zone(zone) {
unsigned long zone_start_pfn, zone_end_pfn;
if (!is_highmem(zone))
continue;
zone_start_pfn = zone->zone_start_pfn;
zone_end_pfn = zone_start_pfn + zone->spanned_pages;
nid = zone_to_nid(zone);
printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n",
zone->name, nid, zone_start_pfn, zone_end_pfn);
add_highpages_with_active_regions(nid, zone_start_pfn,
zone_end_pfn);
}
totalram_pages += totalhigh_pages;
}