leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

xen: add the direct mapping area for ISA bus access

Browse Source 
add the direct mapping area for ISA bus access when running as initial
domain

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Juan Quintela 2010-09-02 15:45:43 +01:00 committed by Stefano Stabellini
parent b37a56d6f3
commit 4ec5387cc3
3 changed files with 28 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/x86/xen/enlighten.c
View File

@ -1186,6 +1186,7 @@ asmlinkage void __init xen_start_kernel(void)
xen_raw_console_write("mapping kernel into physical memory\n"); xen_raw_console_write("mapping kernel into physical memory\n");
pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages); pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
xen_ident_map_ISA();
init_mm.pgd = pgd; init_mm.pgd = pgd;

24
arch/x86/xen/mmu.c
View File

@ -1682,6 +1682,7 @@ static void *m2v(phys_addr_t maddr)
return __ka(m2p(maddr)); return __ka(m2p(maddr));
} }
/* Set the page permissions on an identity-mapped pages */
static void set_page_prot(void *addr, pgprot_t prot) static void set_page_prot(void *addr, pgprot_t prot)
{ {
unsigned long pfn = __pa(addr) >> PAGE_SHIFT; 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 #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) static __init void xen_post_allocator_init(void)
{ {
pv_mmu_ops.set_pte = xen_set_pte; pv_mmu_ops.set_pte = xen_set_pte;

3
arch/x86/xen/setup.c
View File

@ -119,6 +119,9 @@ char * __init xen_memory_setup(void)
* Even though this is normal, usable memory under Xen, reserve * Even though this is normal, usable memory under Xen, reserve
* ISA memory anyway because too many things think they can poke * ISA memory anyway because too many things think they can poke
* about in there. * 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_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
E820_RESERVED); E820_RESERVED);