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author | Juan Quintela <quintela@redhat.com> | 2010-09-02 14:45:43 (GMT) |
---|---|---|
committer | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2010-10-22 20:25:47 (GMT) |
commit | 4ec5387cc36c6472a2ff2c82e9865abe8cab96c2 (patch) | |
tree | 3694b8348b60b084c42abaf590f3db47d6d97b0e /arch/x86/xen | |
parent | b37a56d6f3c0595d8d65ddd5b7610d11735c4978 (diff) | |
download | linux-4ec5387cc36c6472a2ff2c82e9865abe8cab96c2.tar.xz |
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 <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>
Diffstat (limited to 'arch/x86/xen')
-rw-r--r-- | arch/x86/xen/enlighten.c | 1 | ||||
-rw-r--r-- | arch/x86/xen/mmu.c | 24 | ||||
-rw-r--r-- | arch/x86/xen/setup.c | 3 |
3 files changed, 28 insertions, 0 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 1ccfa1b..9efb004 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 ffc5e24..eed9c7c 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 c413132..62ceb78 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); |