diff options
| -rw-r--r-- | arch/x86/xen/enlighten.c | 51 |
1 files changed, 41 insertions, 10 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index e2767c28dac..b011e4a5dbb 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -325,24 +325,55 @@ static unsigned long xen_store_tr(void) return 0; } +/* + * If 'v' is a vmalloc mapping, then find the linear mapping of the + * page (if any) and also set its protections to match: + */ +static void set_aliased_prot(void *v, pgprot_t prot) +{ + int level; + pte_t *ptep; + pte_t pte; + unsigned long pfn; + struct page *page; + + ptep = lookup_address((unsigned long)v, &level); + BUG_ON(ptep == NULL); + + pfn = pte_pfn(*ptep); + page = pfn_to_page(pfn); + + pte = pfn_pte(pfn, prot); + + if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0)) + BUG(); + + if (!PageHighMem(page)) { + void *av = __va(PFN_PHYS(pfn)); + + if (av != v) + if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0)) + BUG(); + } else + kmap_flush_unused(); +} + static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries) { - unsigned pages = roundup(entries * LDT_ENTRY_SIZE, PAGE_SIZE); - void *v = ldt; + const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; int i; - for(i = 0; i < pages; i += PAGE_SIZE) - make_lowmem_page_readonly(v + i); + for(i = 0; i < entries; i += entries_per_page) + set_aliased_prot(ldt + i, PAGE_KERNEL_RO); } static void xen_free_ldt(struct desc_struct *ldt, unsigned entries) { - unsigned pages = roundup(entries * LDT_ENTRY_SIZE, PAGE_SIZE); - void *v = ldt; + const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; int i; - for(i = 0; i < pages; i += PAGE_SIZE) - make_lowmem_page_readwrite(v + i); + for(i = 0; i < entries; i += entries_per_page) + set_aliased_prot(ldt + i, PAGE_KERNEL); } static void xen_set_ldt(const void *addr, unsigned entries) @@ -446,7 +477,7 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, const void *ptr) { unsigned long lp = (unsigned long)&dt[entrynum]; - xmaddr_t mach_lp = virt_to_machine(lp); + xmaddr_t mach_lp = arbitrary_virt_to_machine(lp); u64 entry = *(u64 *)ptr; preempt_disable(); @@ -579,7 +610,7 @@ static void xen_write_gdt_entry(struct desc_struct *dt, int entry, } static void xen_load_sp0(struct tss_struct *tss, - struct thread_struct *thread) + struct thread_struct *thread) { struct multicall_space mcs = xen_mc_entry(0); MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0); |