src/patches/suse-2.6.27.25/patches.xen/805-blkfront-map-sg.patch

   1 From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/63be3e5e2f1a
   2 # HG changeset 805+806 patch
   3 # User Keir Fraser <keir.fraser@citrix.com>
   4 # Date 1236264120 0
   5 # Node ID 63be3e5e2f1a132ce062c446a7d742e3523cf16b
   6 # Parent  f3de83c4677ff77eaf445b3182f00169f6982ce3
   7 Subject: linux/blkfront: use blk_rq_map_sg to generate ring entries
   8 Patch-mainline: 2.6.29
   9 References: bnc#470238
  10
  11 Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
  12 Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
  13 Signed-off-by: Jan Beulich <jbeulich@novell.com>
  14
  15 From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/0430b1dbfb3a
  16 blkfront: Fix the build by expanding sg_init_table() in place.
  17
  18 Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
  19
  20 --- sle11-2009-03-24.orig/drivers/xen/blkfront/blkfront.c       2009-03-24 10:00:15.000000000 +0100
  21 +++ sle11-2009-03-24/drivers/xen/blkfront/blkfront.c    2009-03-05 15:42:00.000000000 +0100
  22 @@ -40,6 +40,7 @@
  23  #include <linux/cdrom.h>
  24  #include <linux/sched.h>
  25  #include <linux/interrupt.h>
  26 +#include <linux/scatterlist.h>
  27  #include <scsi/scsi.h>
  28  #include <xen/evtchn.h>
  29  #include <xen/xenbus.h>
  30 @@ -232,6 +233,8 @@ static int setup_blkring(struct xenbus_d
  31         SHARED_RING_INIT(sring);
  32         FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);
  33
  34 +       memset(info->sg, 0, sizeof(info->sg));
  35 +
  36         err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring));
  37         if (err < 0) {
  38                 free_page((unsigned long)sring);
  39 @@ -587,13 +590,11 @@ static int blkif_queue_request(struct re
  40         struct blkfront_info *info = req->rq_disk->private_data;
  41         unsigned long buffer_mfn;
  42         blkif_request_t *ring_req;
  43 -       struct bio *bio;
  44 -       struct bio_vec *bvec;
  45 -       int idx;
  46         unsigned long id;
  47         unsigned int fsect, lsect;
  48 -       int ref;
  49 +       int i, ref;
  50         grant_ref_t gref_head;
  51 +       struct scatterlist *sg;
  52
  53         if (unlikely(info->connected != BLKIF_STATE_CONNECTED))
  54                 return 1;
  55 @@ -622,14 +623,13 @@ static int blkif_queue_request(struct re
  56         if (blk_barrier_rq(req))
  57                 ring_req->operation = BLKIF_OP_WRITE_BARRIER;
  58
  59 -       ring_req->nr_segments = 0;
  60 -       rq_for_each_bio (bio, req) {
  61 -               bio_for_each_segment (bvec, bio, idx) {
  62 -                       BUG_ON(ring_req->nr_segments
  63 -                              == BLKIF_MAX_SEGMENTS_PER_REQUEST);
  64 -                       buffer_mfn = page_to_phys(bvec->bv_page) >> PAGE_SHIFT;
  65 -                       fsect = bvec->bv_offset >> 9;
  66 -                       lsect = fsect + (bvec->bv_len >> 9) - 1;
  67 +       ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
  68 +       BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
  69 +       for (i = 0; i < ring_req->nr_segments; ++i) {
  70 +                       sg = info->sg + i;
  71 +                       buffer_mfn = page_to_phys(sg->page) >> PAGE_SHIFT;
  72 +                       fsect = sg->offset >> 9;
  73 +                       lsect = fsect + (sg->length >> 9) - 1;
  74                         /* install a grant reference. */
  75                         ref = gnttab_claim_grant_reference(&gref_head);
  76                         BUG_ON(ref == -ENOSPC);
  77 @@ -640,17 +640,12 @@ static int blkif_queue_request(struct re
  78                                 buffer_mfn,
  79                                 rq_data_dir(req) ? GTF_readonly : 0 );
  80
  81 -                       info->shadow[id].frame[ring_req->nr_segments] =
  82 -                               mfn_to_pfn(buffer_mfn);
  83 -
  84 -                       ring_req->seg[ring_req->nr_segments] =
  85 +                       info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
  86 +                       ring_req->seg[i] =
  87                                 (struct blkif_request_segment) {
  88                                         .gref       = ref,
  89                                         .first_sect = fsect,
  90                                         .last_sect  = lsect };
  91 -
  92 -                       ring_req->nr_segments++;
  93 -               }
  94         }
  95
  96         info->ring.req_prod_pvt++;
  97 --- sle11-2009-03-24.orig/drivers/xen/blkfront/block.h  2009-03-24 10:00:15.000000000 +0100
  98 +++ sle11-2009-03-24/drivers/xen/blkfront/block.h       2009-03-05 15:42:00.000000000 +0100
  99 @@ -103,6 +103,7 @@ struct blkfront_info
 100         int connected;
 101         int ring_ref;
 102         blkif_front_ring_t ring;
 103 +       struct scatterlist sg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
 104         unsigned int irq;
 105         struct xlbd_major_info *mi;
 106         request_queue_t *rq;