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Merge branch 'tmpalias-flush' into for-next
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James Bottomley authored and James Bottomley committed Feb 10, 2011
2 parents 6148a47 + 8b4ae33 commit e9a623b
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Showing 5 changed files with 260 additions and 332 deletions.
7 changes: 4 additions & 3 deletions arch/parisc/include/asm/cacheflush.h
Original file line number Diff line number Diff line change
Expand Up @@ -26,8 +26,6 @@ void flush_user_dcache_range_asm(unsigned long, unsigned long);
void flush_kernel_dcache_range_asm(unsigned long, unsigned long);
void flush_kernel_dcache_page_asm(void *);
void flush_kernel_icache_page(void *);
void flush_user_dcache_page(unsigned long);
void flush_user_icache_page(unsigned long);
void flush_user_dcache_range(unsigned long, unsigned long);
void flush_user_icache_range(unsigned long, unsigned long);

Expand Down Expand Up @@ -90,12 +88,15 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned
void flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end);

/* defined in pacache.S exported in cache.c used by flush_anon_page */
void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);

#define ARCH_HAS_FLUSH_ANON_PAGE
static inline void
flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
{
if (PageAnon(page))
flush_user_dcache_page(vmaddr);
flush_dcache_page_asm(page_to_phys(page), vmaddr);
}

#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
Expand Down
14 changes: 4 additions & 10 deletions arch/parisc/include/asm/pgtable.h
Original file line number Diff line number Diff line change
Expand Up @@ -138,8 +138,7 @@ struct vm_area_struct;
#define _PAGE_NO_CACHE_BIT 24 /* (0x080) Uncached Page (U bit) */
#define _PAGE_ACCESSED_BIT 23 /* (0x100) Software: Page Accessed */
#define _PAGE_PRESENT_BIT 22 /* (0x200) Software: translation valid */
#define _PAGE_FLUSH_BIT 21 /* (0x400) Software: translation valid */
/* for cache flushing only */
/* bit 21 was formerly the FLUSH bit but is now unused */
#define _PAGE_USER_BIT 20 /* (0x800) Software: User accessible page */

/* N.B. The bits are defined in terms of a 32 bit word above, so the */
Expand Down Expand Up @@ -173,7 +172,6 @@ struct vm_area_struct;
#define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
#define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
#define _PAGE_PRESENT (1 << xlate_pabit(_PAGE_PRESENT_BIT))
#define _PAGE_FLUSH (1 << xlate_pabit(_PAGE_FLUSH_BIT))
#define _PAGE_USER (1 << xlate_pabit(_PAGE_USER_BIT))
#define _PAGE_FILE (1 << xlate_pabit(_PAGE_FILE_BIT))

Expand Down Expand Up @@ -213,7 +211,6 @@ struct vm_area_struct;
#define PAGE_KERNEL_RO __pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
#define PAGE_KERNEL_UNC __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
#define PAGE_GATEWAY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)
#define PAGE_FLUSH __pgprot(_PAGE_FLUSH)


/*
Expand Down Expand Up @@ -261,7 +258,7 @@ extern unsigned long *empty_zero_page;

#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))

#define pte_none(x) ((pte_val(x) == 0) || (pte_val(x) & _PAGE_FLUSH))
#define pte_none(x) (pte_val(x) == 0)
#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
#define pte_clear(mm,addr,xp) do { pte_val(*(xp)) = 0; } while (0)

Expand Down Expand Up @@ -444,13 +441,10 @@ struct mm_struct;
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t old_pte;
pte_t pte;

spin_lock(&pa_dbit_lock);
pte = old_pte = *ptep;
pte_val(pte) &= ~_PAGE_PRESENT;
pte_val(pte) |= _PAGE_FLUSH;
set_pte_at(mm,addr,ptep,pte);
old_pte = *ptep;
pte_clear(mm,addr,ptep);
spin_unlock(&pa_dbit_lock);

return old_pte;
Expand Down
109 changes: 17 additions & 92 deletions arch/parisc/kernel/cache.c
Original file line number Diff line number Diff line change
Expand Up @@ -27,12 +27,17 @@
#include <asm/pgalloc.h>
#include <asm/processor.h>
#include <asm/sections.h>
#include <asm/shmparam.h>

int split_tlb __read_mostly;
int dcache_stride __read_mostly;
int icache_stride __read_mostly;
EXPORT_SYMBOL(dcache_stride);

void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
EXPORT_SYMBOL(flush_dcache_page_asm);
void flush_icache_page_asm(unsigned long phys_addr, unsigned long vaddr);


/* On some machines (e.g. ones with the Merced bus), there can be
* only a single PxTLB broadcast at a time; this must be guaranteed
Expand Down Expand Up @@ -259,81 +264,13 @@ void disable_sr_hashing(void)
panic("SpaceID hashing is still on!\n");
}

/* Simple function to work out if we have an existing address translation
* for a user space vma. */
static inline int translation_exists(struct vm_area_struct *vma,
unsigned long addr, unsigned long pfn)
{
pgd_t *pgd = pgd_offset(vma->vm_mm, addr);
pmd_t *pmd;
pte_t pte;

if(pgd_none(*pgd))
return 0;

pmd = pmd_offset(pgd, addr);
if(pmd_none(*pmd) || pmd_bad(*pmd))
return 0;

/* We cannot take the pte lock here: flush_cache_page is usually
* called with pte lock already held. Whereas flush_dcache_page
* takes flush_dcache_mmap_lock, which is lower in the hierarchy:
* the vma itself is secure, but the pte might come or go racily.
*/
pte = *pte_offset_map(pmd, addr);
/* But pte_unmap() does nothing on this architecture */

/* Filter out coincidental file entries and swap entries */
if (!(pte_val(pte) & (_PAGE_FLUSH|_PAGE_PRESENT)))
return 0;

return pte_pfn(pte) == pfn;
}

/* Private function to flush a page from the cache of a non-current
* process. cr25 contains the Page Directory of the current user
* process; we're going to hijack both it and the user space %sr3 to
* temporarily make the non-current process current. We have to do
* this because cache flushing may cause a non-access tlb miss which
* the handlers have to fill in from the pgd of the non-current
* process. */
static inline void
flush_user_cache_page_non_current(struct vm_area_struct *vma,
unsigned long vmaddr)
__flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
unsigned long physaddr)
{
/* save the current process space and pgd */
unsigned long space = mfsp(3), pgd = mfctl(25);

/* we don't mind taking interrupts since they may not
* do anything with user space, but we can't
* be preempted here */
preempt_disable();

/* make us current */
mtctl(__pa(vma->vm_mm->pgd), 25);
mtsp(vma->vm_mm->context, 3);

flush_user_dcache_page(vmaddr);
if(vma->vm_flags & VM_EXEC)
flush_user_icache_page(vmaddr);

/* put the old current process back */
mtsp(space, 3);
mtctl(pgd, 25);
preempt_enable();
}


static inline void
__flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
if (likely(vma->vm_mm->context == mfsp(3))) {
flush_user_dcache_page(vmaddr);
if (vma->vm_flags & VM_EXEC)
flush_user_icache_page(vmaddr);
} else {
flush_user_cache_page_non_current(vma, vmaddr);
}
flush_dcache_page_asm(physaddr, vmaddr);
if (vma->vm_flags & VM_EXEC)
flush_icache_page_asm(physaddr, vmaddr);
}

void flush_dcache_page(struct page *page)
Expand All @@ -342,10 +279,8 @@ void flush_dcache_page(struct page *page)
struct vm_area_struct *mpnt;
struct prio_tree_iter iter;
unsigned long offset;
unsigned long addr;
unsigned long addr, old_addr = 0;
pgoff_t pgoff;
unsigned long pfn = page_to_pfn(page);


if (mapping && !mapping_mapped(mapping)) {
set_bit(PG_dcache_dirty, &page->flags);
Expand All @@ -369,20 +304,11 @@ void flush_dcache_page(struct page *page)
offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
addr = mpnt->vm_start + offset;

/* Flush instructions produce non access tlb misses.
* On PA, we nullify these instructions rather than
* taking a page fault if the pte doesn't exist.
* This is just for speed. If the page translation
* isn't there, there's no point exciting the
* nadtlb handler into a nullification frenzy.
*
* Make sure we really have this page: the private
* mappings may cover this area but have COW'd this
* particular page.
*/
if (translation_exists(mpnt, addr, pfn)) {
__flush_cache_page(mpnt, addr);
break;
if (old_addr == 0 || (old_addr & (SHMLBA - 1)) != (addr & (SHMLBA - 1))) {
__flush_cache_page(mpnt, addr, page_to_phys(page));
if (old_addr)
printk(KERN_ERR "INEQUIVALENT ALIASES 0x%lx and 0x%lx in file %s\n", old_addr, addr, mpnt->vm_file ? mpnt->vm_file->f_path.dentry->d_name.name : "(null)");
old_addr = addr;
}
}
flush_dcache_mmap_unlock(mapping);
Expand Down Expand Up @@ -573,7 +499,6 @@ flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long
{
BUG_ON(!vma->vm_mm->context);

if (likely(translation_exists(vma, vmaddr, pfn)))
__flush_cache_page(vma, vmaddr);
__flush_cache_page(vma, vmaddr, page_to_phys(pfn_to_page(pfn)));

}
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