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Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r--arch/x86/mm/fault.c107
1 files changed, 1 insertions, 106 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 8d2472be4..e830c71a1 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -13,7 +13,6 @@
#include <linux/hugetlb.h> /* hstate_index_to_shift */
#include <linux/prefetch.h> /* prefetchw */
#include <linux/context_tracking.h> /* exception_enter(), ... */
-#include <linux/tuxonice.h> /* incremental image support */
#include <linux/uaccess.h> /* faulthandler_disabled() */
#include <asm/traps.h> /* dotraplinkage, ... */
@@ -663,10 +662,6 @@ no_context(struct pt_regs *regs, unsigned long error_code,
unsigned long flags;
int sig;
- if (toi_make_writable(init_mm.pgd, address)) {
- return;
- }
-
/* Are we prepared to handle this kernel fault? */
if (fixup_exception(regs)) {
/*
@@ -921,101 +916,10 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
}
}
-#ifdef CONFIG_TOI_INCREMENTAL
-/**
- * _toi_do_cbw - Do a copy-before-write before letting the faulting process continue
- */
-static void toi_do_cbw(struct page *page)
-{
- struct toi_cbw_state *state = this_cpu_ptr(&toi_cbw_states);
-
- state->active = 1;
- wmb();
-
- if (state->enabled && state->next && PageTOI_CBW(page)) {
- struct toi_cbw *this = state->next;
- memcpy(this->virt, page_address(page), PAGE_SIZE);
- this->pfn = page_to_pfn(page);
- state->next = this->next;
- }
-
- state->active = 0;
-}
-
-/**
- * _toi_make_writable - Defuse TOI's write protection
- */
-int _toi_make_writable(pte_t *pte)
-{
- struct page *page = pte_page(*pte);
- if (PageTOI_RO(page)) {
- pgd_t *pgd = __va(read_cr3());
- /*
- * If this is a TuxOnIce caused fault, we may not have permission to
- * write to a page needed to reset the permissions of the original
- * page. Use swapper_pg_dir to get around this.
- */
- load_cr3(swapper_pg_dir);
-
- set_pte_atomic(pte, pte_mkwrite(*pte));
- SetPageTOI_Dirty(page);
- ClearPageTOI_RO(page);
-
- toi_do_cbw(page);
-
- load_cr3(pgd);
- return 1;
- }
- return 0;
-}
-
-/**
- * toi_make_writable - Handle a (potential) fault caused by TOI's write protection
- *
- * Make a page writable that was protected. Might be because of a fault, or
- * because we're allocating it and want it to be untracked.
- *
- * Note that in the fault handling case, we don't care about the error code. If
- * called from the double fault handler, we won't have one. We just check to
- * see if the page was made RO by TOI, and mark it dirty/release the protection
- * if it was.
- */
-int toi_make_writable(pgd_t *pgd, unsigned long address)
-{
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
- pgd = pgd + pgd_index(address);
- if (!pgd_present(*pgd))
- return 0;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return 0;
-
- if (pud_large(*pud))
- return _toi_make_writable((pte_t *) pud);
-
- pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd))
- return 0;
-
- if (pmd_large(*pmd))
- return _toi_make_writable((pte_t *) pmd);
-
- pte = pte_offset_kernel(pmd, address);
- if (!pte_present(*pte))
- return 0;
-
- return _toi_make_writable(pte);
-}
-#endif
-
static int spurious_fault_check(unsigned long error_code, pte_t *pte)
{
if ((error_code & PF_WRITE) && !pte_write(*pte))
- return 0;
+ return 0;
if ((error_code & PF_INSTR) && !pte_exec(*pte))
return 0;
@@ -1178,15 +1082,6 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
kmemcheck_hide(regs);
prefetchw(&mm->mmap_sem);
- /*
- * Detect and handle page faults due to TuxOnIce making pages read-only
- * so that it can create incremental images.
- *
- * Do it early to avoid double faults.
- */
- if (unlikely(toi_make_writable(init_mm.pgd, address)))
- return;
-
if (unlikely(kmmio_fault(regs, address)))
return;