diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/lguest/page_tables.c | 38 |
1 files changed, 21 insertions, 17 deletions
diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c index 5e2c26a..a6fe1ab 100644 --- a/drivers/lguest/page_tables.c +++ b/drivers/lguest/page_tables.c @@ -154,26 +154,25 @@ static unsigned long gpmd_addr(pgd_t gpgd, unsigned long vaddr) BUG_ON(!(pgd_flags(gpgd) & _PAGE_PRESENT)); return gpage + pmd_index(vaddr) * sizeof(pmd_t); } -#endif static unsigned long gpte_addr(struct lg_cpu *cpu, - pgd_t gpgd, unsigned long vaddr) + pmd_t gpmd, unsigned long vaddr) { -#ifdef CONFIG_X86_PAE - pmd_t gpmd; -#endif - unsigned long gpage; + unsigned long gpage = pmd_pfn(gpmd) << PAGE_SHIFT; - BUG_ON(!(pgd_flags(gpgd) & _PAGE_PRESENT)); -#ifdef CONFIG_X86_PAE - gpmd = lgread(cpu, gpmd_addr(gpgd, vaddr), pmd_t); - gpage = pmd_pfn(gpmd) << PAGE_SHIFT; BUG_ON(!(pmd_flags(gpmd) & _PAGE_PRESENT)); + return gpage + pte_index(vaddr) * sizeof(pte_t); +} #else - gpage = pgd_pfn(gpgd) << PAGE_SHIFT; -#endif +static unsigned long gpte_addr(struct lg_cpu *cpu, + pgd_t gpgd, unsigned long vaddr) +{ + unsigned long gpage = pgd_pfn(gpgd) << PAGE_SHIFT; + + BUG_ON(!(pgd_flags(gpgd) & _PAGE_PRESENT)); return gpage + pte_index(vaddr) * sizeof(pte_t); } +#endif /*:*/ /*M:014 get_pfn is slow: we could probably try to grab batches of pages here as @@ -339,10 +338,15 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode) * number in the shadow PMD is the page we just allocated. */ native_set_pmd(spmd, __pmd(__pa(ptepage) | pmd_flags(gpmd))); } -#endif + + /* OK, now we look at the lower level in the Guest page table: keep its + * address, because we might update it later. */ + gpte_ptr = gpte_addr(cpu, gpmd, vaddr); +#else /* OK, now we look at the lower level in the Guest page table: keep its * address, because we might update it later. */ gpte_ptr = gpte_addr(cpu, gpgd, vaddr); +#endif gpte = lgread(cpu, gpte_ptr, pte_t); /* If this page isn't in the Guest page tables, we can't page it in. */ @@ -522,7 +526,6 @@ unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr) { pgd_t gpgd; pte_t gpte; - #ifdef CONFIG_X86_PAE pmd_t gpmd; #endif @@ -534,13 +537,14 @@ unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr) return -1UL; } - gpte = lgread(cpu, gpte_addr(cpu, gpgd, vaddr), pte_t); #ifdef CONFIG_X86_PAE gpmd = lgread(cpu, gpmd_addr(gpgd, vaddr), pmd_t); if (!(pmd_flags(gpmd) & _PAGE_PRESENT)) kill_guest(cpu, "Bad address %#lx", vaddr); -#endif + gpte = lgread(cpu, gpte_addr(cpu, gpmd, vaddr), pte_t); +#else gpte = lgread(cpu, gpte_addr(cpu, gpgd, vaddr), pte_t); +#endif if (!(pte_flags(gpte) & _PAGE_PRESENT)) kill_guest(cpu, "Bad address %#lx", vaddr); @@ -847,7 +851,7 @@ static unsigned long setup_pagetables(struct lguest *lg, /* The top level points to the linear page table pages above. * We setup the identity and linear mappings here. */ #ifdef CONFIG_X86_PAE - for (i = 0, j; i < mapped_pages && j < PTRS_PER_PMD; + for (i = j = 0; i < mapped_pages && j < PTRS_PER_PMD; i += PTRS_PER_PTE, j++) { native_set_pmd(&pmd, __pmd(((unsigned long)(linear + i) - mem_base) | _PAGE_PRESENT | _PAGE_RW | _PAGE_USER)); |