From 2d073846b891c3f49c4ea03c5db3ac92f92742f1 Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Thu, 29 Sep 2011 16:53:30 +0100 Subject: [PATCH] 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 Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk --- drivers/block/xen-blkback/common.h | 5 +-- drivers/block/xen-blkback/xenbus.c | 54 ++++-------------------------- 2 files changed, 8 insertions(+), 51 deletions(-) diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index 00c57c90e2d6..7ec0e8896a78 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -139,7 +139,7 @@ struct xen_blkif { /* Comms information. */ enum blkif_protocol blk_protocol; union blkif_back_rings blk_rings; - struct vm_struct *blk_ring_area; + void *blk_ring; /* The VBD attached to this interface. */ struct xen_vbd vbd; /* Back pointer to the backend_info. */ @@ -163,9 +163,6 @@ struct xen_blkif { int st_wr_sect; wait_queue_head_t waiting_to_free; - - grant_handle_t shmem_handle; - grant_ref_t shmem_ref; }; diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 5fd2010f7d2b..69233dd42212 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -120,38 +120,6 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid) 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 @@ static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page, 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 @@ static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page, 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 @@ static void xen_blkif_disconnect(struct xen_blkif *blkif) } 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; } }