From 51de69523ffe1c17994dc2f260369f29dfdce71c Mon Sep 17 00:00:00 2001 From: Owen Smith Date: Wed, 22 Dec 2010 15:05:00 +0000 Subject: [PATCH] xen: Union the blkif_request request specific fields Prepare for extending the block device ring to allow request specific fields, by moving the request specific fields for reads, writes and barrier requests to a union member. Acked-by: Jens Axboe Signed-off-by: Owen Smith Signed-off-by: Konrad Rzeszutek Wilk --- drivers/block/xen-blkfront.c | 8 ++++---- include/xen/interface/io/blkif.h | 16 +++++++++++----- 2 files changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index d7aa39e349a6..cc4514c9d8a6 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -281,7 +281,7 @@ static int blkif_queue_request(struct request *req) info->shadow[id].request = req; ring_req->id = id; - ring_req->sector_number = (blkif_sector_t)blk_rq_pos(req); + ring_req->u.rw.sector_number = (blkif_sector_t)blk_rq_pos(req); ring_req->handle = info->handle; ring_req->operation = rq_data_dir(req) ? @@ -317,7 +317,7 @@ static int blkif_queue_request(struct request *req) rq_data_dir(req) ); info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn); - ring_req->seg[i] = + ring_req->u.rw.seg[i] = (struct blkif_request_segment) { .gref = ref, .first_sect = fsect, @@ -615,7 +615,7 @@ static void blkif_completion(struct blk_shadow *s) { int i; for (i = 0; i < s->req.nr_segments; i++) - gnttab_end_foreign_access(s->req.seg[i].gref, 0, 0UL); + gnttab_end_foreign_access(s->req.u.rw.seg[i].gref, 0, 0UL); } static irqreturn_t blkif_interrupt(int irq, void *dev_id) @@ -932,7 +932,7 @@ static int blkif_recover(struct blkfront_info *info) /* Rewrite any grant references invalidated by susp/resume. */ for (j = 0; j < req->nr_segments; j++) gnttab_grant_foreign_access_ref( - req->seg[j].gref, + req->u.rw.seg[j].gref, info->xbdev->otherend_id, pfn_to_mfn(info->shadow[req->id].frame[j]), rq_data_dir(info->shadow[req->id].request)); diff --git a/include/xen/interface/io/blkif.h b/include/xen/interface/io/blkif.h index c2d1fa4dc1ee..e4f743cfa151 100644 --- a/include/xen/interface/io/blkif.h +++ b/include/xen/interface/io/blkif.h @@ -51,11 +51,7 @@ typedef uint64_t blkif_sector_t; */ #define BLKIF_MAX_SEGMENTS_PER_REQUEST 11 -struct blkif_request { - uint8_t operation; /* BLKIF_OP_??? */ - uint8_t nr_segments; /* number of segments */ - blkif_vdev_t handle; /* only for read/write requests */ - uint64_t id; /* private guest value, echoed in resp */ +struct blkif_request_rw { blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */ struct blkif_request_segment { grant_ref_t gref; /* reference to I/O buffer frame */ @@ -65,6 +61,16 @@ struct blkif_request { } seg[BLKIF_MAX_SEGMENTS_PER_REQUEST]; }; +struct blkif_request { + uint8_t operation; /* BLKIF_OP_??? */ + uint8_t nr_segments; /* number of segments */ + blkif_vdev_t handle; /* only for read/write requests */ + uint64_t id; /* private guest value, echoed in resp */ + union { + struct blkif_request_rw rw; + } u; +}; + struct blkif_response { uint64_t id; /* copied from request */ uint8_t operation; /* copied from request */ -- 2.20.1