diff options
author | David Vrabel <david.vrabel@citrix.com> | 2011-09-29 19:53:32 +0400 |
---|---|---|
committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-11-16 21:13:08 +0400 |
commit | cd12909cb576d37311fe35868780e82d5007d0c8 (patch) | |
tree | 70ec60af4feb32087f542a838fe4dce8717f0cd6 /drivers/xen | |
parent | 1ea6b8f48918282bdca0b32a34095504ee65bab5 (diff) | |
download | linux-cd12909cb576d37311fe35868780e82d5007d0c8.tar.xz |
xen: map foreign pages for shared rings by updating the PTEs directly
When mapping a foreign page with xenbus_map_ring_valloc() with the
GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and
pass a pointer to the PTE (in init_mm).
After the page is mapped, the usual fault mechanism can be used to
update additional MMs. This allows the vmalloc_sync_all() to be
removed from alloc_vm_area().
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
[v1: Squashed fix by Michal for no-mmu case]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
Diffstat (limited to 'drivers/xen')
-rw-r--r-- | drivers/xen/xenbus/xenbus_client.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c index 81c3ce6b8bbe..1906125eab49 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -35,6 +35,7 @@ #include <linux/vmalloc.h> #include <linux/export.h> #include <asm/xen/hypervisor.h> +#include <asm/xen/page.h> #include <xen/interface/xen.h> #include <xen/interface/event_channel.h> #include <xen/events.h> @@ -436,19 +437,20 @@ EXPORT_SYMBOL_GPL(xenbus_free_evtchn); int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr) { struct gnttab_map_grant_ref op = { - .flags = GNTMAP_host_map, + .flags = GNTMAP_host_map | GNTMAP_contains_pte, .ref = gnt_ref, .dom = dev->otherend_id, }; struct vm_struct *area; + pte_t *pte; *vaddr = NULL; - area = alloc_vm_area(PAGE_SIZE); + area = alloc_vm_area(PAGE_SIZE, &pte); if (!area) return -ENOMEM; - op.host_addr = (unsigned long)area->addr; + op.host_addr = arbitrary_virt_to_machine(pte).maddr; if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1)) BUG(); @@ -527,6 +529,7 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr) struct gnttab_unmap_grant_ref op = { .host_addr = (unsigned long)vaddr, }; + unsigned int level; /* It'd be nice if linux/vmalloc.h provided a find_vm_area(void *addr) * method so that we don't have to muck with vmalloc internals here. @@ -548,6 +551,8 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr) } op.handle = (grant_handle_t)area->phys_addr; + op.host_addr = arbitrary_virt_to_machine( + lookup_address((unsigned long)vaddr, &level)).maddr; if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1)) BUG(); |