From 4ec5387cc36c6472a2ff2c82e9865abe8cab96c2 Mon Sep 17 00:00:00 2001 From: Juan Quintela Date: Thu, 2 Sep 2010 15:45:43 +0100 Subject: xen: add the direct mapping area for ISA bus access add the direct mapping area for ISA bus access when running as initial domain Signed-off-by: Juan Quintela Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Stefano Stabellini Reviewed-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 1 + arch/x86/xen/mmu.c | 24 ++++++++++++++++++++++++ arch/x86/xen/setup.c | 3 +++ 3 files changed, 28 insertions(+) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 1ccfa1bf0f89..9efb00446250 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1186,6 +1186,7 @@ asmlinkage void __init xen_start_kernel(void) xen_raw_console_write("mapping kernel into physical memory\n"); pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages); + xen_ident_map_ISA(); init_mm.pgd = pgd; diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index ffc5e24a53ba..eed9c7cee4b7 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1682,6 +1682,7 @@ static void *m2v(phys_addr_t maddr) return __ka(m2p(maddr)); } +/* Set the page permissions on an identity-mapped pages */ static void set_page_prot(void *addr, pgprot_t prot) { unsigned long pfn = __pa(addr) >> PAGE_SHIFT; @@ -1929,6 +1930,29 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) #endif } +__init void xen_ident_map_ISA(void) +{ + unsigned long pa; + + /* + * If we're dom0, then linear map the ISA machine addresses into + * the kernel's address space. + */ + if (!xen_initial_domain()) + return; + + xen_raw_printk("Xen: setup ISA identity maps\n"); + + for (pa = ISA_START_ADDRESS; pa < ISA_END_ADDRESS; pa += PAGE_SIZE) { + pte_t pte = mfn_pte(PFN_DOWN(pa), PAGE_KERNEL_IO); + + if (HYPERVISOR_update_va_mapping(PAGE_OFFSET + pa, pte, 0)) + BUG(); + } + + xen_flush_tlb(); +} + static __init void xen_post_allocator_init(void) { pv_mmu_ops.set_pte = xen_set_pte; diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index c413132702f7..62ceb7864017 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -119,6 +119,9 @@ char * __init xen_memory_setup(void) * Even though this is normal, usable memory under Xen, reserve * ISA memory anyway because too many things think they can poke * about in there. + * + * In a dom0 kernel, this region is identity mapped with the + * hardware ISA area, so it really is out of bounds. */ e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_RESERVED); -- cgit v1.2.3