On Thu, 26 Jul 2012, Konrad Rzeszutek Wilk wrote:
On Thu, Jul 26, 2012 at 04:33:45PM +0100, Stefano Stabellini wrote:
ARM Xen guests always use paging in hardware, like PV on HVM guests in the X86 world.
Nice, so no dealing with the P2M at all in the guest?
Nope ;-)
Signed-off-by: Stefano Stabellini stefano.stabellini@eu.citrix.com
arch/arm/include/asm/xen/page.h | 77 +++++++++++++++++++++++++++++++++++++++ 1 files changed, 77 insertions(+), 0 deletions(-) create mode 100644 arch/arm/include/asm/xen/page.h
diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h new file mode 100644 index 0000000..6cfe9a1 --- /dev/null +++ b/arch/arm/include/asm/xen/page.h @@ -0,0 +1,77 @@ +#ifndef _ASM_ARM_XEN_PAGE_H +#define _ASM_ARM_XEN_PAGE_H
+#include <asm/page.h> +#include <linux/pfn.h> +#include <linux/types.h> +#include <asm/pgtable.h> +#include <xen/interface/grant_table.h>
I don't if it makes such a difference, but putting the headers in sorted order is sometimes nicer than just randomly.. But that might be just me liking an orderly world nowadays :-)
I can do that
+#define pfn_to_mfn(pfn) (pfn) +#define phys_to_machine_mapping_valid (1) +#define mfn_to_pfn(mfn) (mfn) +#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
+#define pte_mfn pte_pfn +#define mfn_pte pfn_pte
+/* Xen machine address */ +typedef struct xmaddr {
- phys_addr_t maddr;
+} xmaddr_t;
+/* Xen pseudo-physical address */ +typedef struct xpaddr {
- phys_addr_t paddr;
+} xpaddr_t;
+#define XMADDR(x) ((xmaddr_t) { .maddr = (x) }) +#define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
+static inline xmaddr_t phys_to_machine(xpaddr_t phys) +{
- unsigned offset = phys.paddr & ~PAGE_MASK;
- return XMADDR(PFN_PHYS(pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
+}
+static inline xpaddr_t machine_to_phys(xmaddr_t machine) +{
- unsigned offset = machine.maddr & ~PAGE_MASK;
- return XPADDR(PFN_PHYS(mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
+} +/* VIRT <-> MACHINE conversion */ +#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) +#define virt_to_pfn(v) (PFN_DOWN(__pa(v))) +#define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v))) +#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
+static inline xmaddr_t arbitrary_virt_to_machine(void *vaddr) +{
- /* XXX: assuming it is mapped in the kernel 1:1 */
- return virt_to_machine(vaddr);
+}
+/* XXX: this shouldn't be here */
So why is it here?
lookup_address shouldn't be here because it is an x86-only interface. However both gntdev.c and xenbus_client.c call it (in PV only code paths that are never taken in a PV on HVM guest), so in order to compile them I have to define lookup_address.
+static inline pte_t *lookup_address(unsigned long address, unsigned int *level) +{
- BUG();
- return NULL;
+}
+static inline int m2p_add_override(unsigned long mfn, struct page *page,
struct gnttab_map_grant_ref *kmap_op)+{
- return 0;
+}
+static inline int m2p_remove_override(struct page *page, bool clear_pte) +{
- return 0;
+}
+static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn) +{
- BUG();
- return false;
+} +#endif /* _ASM_ARM_XEN_PAGE_H */