block: xen-blkback: use API provided by xenbus module to map rings
The xenbus module provides xenbus_map_ring_valloc() and
xenbus_map_ring_vfree(). Use these to map the ring pages granted by
the frontend.
Acked-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 5fd2010..69233dd 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -120,38 +120,6 @@
return blkif;
}
-static int map_frontend_page(struct xen_blkif *blkif, unsigned long shared_page)
-{
- struct gnttab_map_grant_ref op;
-
- gnttab_set_map_op(&op, (unsigned long)blkif->blk_ring_area->addr,
- GNTMAP_host_map, shared_page, blkif->domid);
-
- if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
- BUG();
-
- if (op.status) {
- DPRINTK("Grant table operation failure !\n");
- return op.status;
- }
-
- blkif->shmem_ref = shared_page;
- blkif->shmem_handle = op.handle;
-
- return 0;
-}
-
-static void unmap_frontend_page(struct xen_blkif *blkif)
-{
- struct gnttab_unmap_grant_ref op;
-
- gnttab_set_unmap_op(&op, (unsigned long)blkif->blk_ring_area->addr,
- GNTMAP_host_map, blkif->shmem_handle);
-
- if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
- BUG();
-}
-
static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page,
unsigned int evtchn)
{
@@ -161,35 +129,29 @@
if (blkif->irq)
return 0;
- blkif->blk_ring_area = alloc_vm_area(PAGE_SIZE);
- if (!blkif->blk_ring_area)
- return -ENOMEM;
-
- err = map_frontend_page(blkif, shared_page);
- if (err) {
- free_vm_area(blkif->blk_ring_area);
+ err = xenbus_map_ring_valloc(blkif->be->dev, shared_page, &blkif->blk_ring);
+ if (err < 0)
return err;
- }
switch (blkif->blk_protocol) {
case BLKIF_PROTOCOL_NATIVE:
{
struct blkif_sring *sring;
- sring = (struct blkif_sring *)blkif->blk_ring_area->addr;
+ sring = (struct blkif_sring *)blkif->blk_ring;
BACK_RING_INIT(&blkif->blk_rings.native, sring, PAGE_SIZE);
break;
}
case BLKIF_PROTOCOL_X86_32:
{
struct blkif_x86_32_sring *sring_x86_32;
- sring_x86_32 = (struct blkif_x86_32_sring *)blkif->blk_ring_area->addr;
+ sring_x86_32 = (struct blkif_x86_32_sring *)blkif->blk_ring;
BACK_RING_INIT(&blkif->blk_rings.x86_32, sring_x86_32, PAGE_SIZE);
break;
}
case BLKIF_PROTOCOL_X86_64:
{
struct blkif_x86_64_sring *sring_x86_64;
- sring_x86_64 = (struct blkif_x86_64_sring *)blkif->blk_ring_area->addr;
+ sring_x86_64 = (struct blkif_x86_64_sring *)blkif->blk_ring;
BACK_RING_INIT(&blkif->blk_rings.x86_64, sring_x86_64, PAGE_SIZE);
break;
}
@@ -201,8 +163,7 @@
xen_blkif_be_int, 0,
"blkif-backend", blkif);
if (err < 0) {
- unmap_frontend_page(blkif);
- free_vm_area(blkif->blk_ring_area);
+ xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring);
blkif->blk_rings.common.sring = NULL;
return err;
}
@@ -228,8 +189,7 @@
}
if (blkif->blk_rings.common.sring) {
- unmap_frontend_page(blkif);
- free_vm_area(blkif->blk_ring_area);
+ xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring);
blkif->blk_rings.common.sring = NULL;
}
}