Merge branches 'tracing/doc', 'tracing/ftrace', 'tracing/printk' and 'linus' into...

[linux-2.6-omap-h63xx.git] / drivers / block / xen-blkfront.c

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 918ef725de41c849f3f78b7e30f80d7709e01a39..8f905089b72b7e49c2434d1b6abba9fa76321051 100644 (file)
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -40,6 +40,7 @@
 #include <linux/hdreg.h>
 #include <linux/cdrom.h>
 #include <linux/module.h>
+#include <linux/scatterlist.h>
 
 #include <xen/xenbus.h>
 #include <xen/grant_table.h>
@@ -82,6 +83,7 @@ struct blkfront_info
        enum blkif_state connected;
        int ring_ref;
        struct blkif_front_ring ring;
+       struct scatterlist sg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
        unsigned int evtchn, irq;
        struct request_queue *rq;
        struct work_struct work;
@@ -204,12 +206,11 @@ static int blkif_queue_request(struct request *req)
        struct blkfront_info *info = req->rq_disk->private_data;
        unsigned long buffer_mfn;
        struct blkif_request *ring_req;
-       struct req_iterator iter;
-       struct bio_vec *bvec;
        unsigned long id;
        unsigned int fsect, lsect;
-       int ref;
+       int i, ref;
        grant_ref_t gref_head;
+       struct scatterlist *sg;
 
        if (unlikely(info->connected != BLKIF_STATE_CONNECTED))
                return 1;
@@ -238,12 +239,13 @@ static int blkif_queue_request(struct request *req)
        if (blk_barrier_rq(req))
                ring_req->operation = BLKIF_OP_WRITE_BARRIER;
 
-       ring_req->nr_segments = 0;
-       rq_for_each_segment(bvec, req, iter) {
-               BUG_ON(ring_req->nr_segments == BLKIF_MAX_SEGMENTS_PER_REQUEST);
-               buffer_mfn = pfn_to_mfn(page_to_pfn(bvec->bv_page));
-               fsect = bvec->bv_offset >> 9;
-               lsect = fsect + (bvec->bv_len >> 9) - 1;
+       ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
+       BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
+
+       for_each_sg(info->sg, sg, ring_req->nr_segments, i) {
+               buffer_mfn = pfn_to_mfn(page_to_pfn(sg_page(sg)));
+               fsect = sg->offset >> 9;
+               lsect = fsect + (sg->length >> 9) - 1;
                /* install a grant reference. */
                ref = gnttab_claim_grant_reference(&gref_head);
                BUG_ON(ref == -ENOSPC);
@@ -254,16 +256,12 @@ static int blkif_queue_request(struct request *req)
                                buffer_mfn,
                                rq_data_dir(req) );
 
-               info->shadow[id].frame[ring_req->nr_segments] =
-                               mfn_to_pfn(buffer_mfn);
-
-               ring_req->seg[ring_req->nr_segments] =
+               info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
+               ring_req->seg[i] =
                                (struct blkif_request_segment) {
                                        .gref       = ref,
                                        .first_sect = fsect,
                                        .last_sect  = lsect };
-
-               ring_req->nr_segments++;
        }
 
        info->ring.req_prod_pvt++;
@@ -622,6 +620,8 @@ static int setup_blkring(struct xenbus_device *dev,
        SHARED_RING_INIT(sring);
        FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);
 
+       sg_init_table(info->sg, BLKIF_MAX_SEGMENTS_PER_REQUEST);
+
        err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring));
        if (err < 0) {
                free_page((unsigned long)sring);
@@ -977,6 +977,8 @@ static void backend_changed(struct xenbus_device *dev,
                break;
 
        case XenbusStateClosing:
+               if (info->gd == NULL)
+                       xenbus_dev_fatal(dev, -ENODEV, "gd is NULL");
                bd = bdget_disk(info->gd, 0);
                if (bd == NULL)
                        xenbus_dev_fatal(dev, -ENODEV, "bdget failed");