3 files changed, 78 insertions, 44 deletions

diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index de1f319f7bd7..dd5b2fed97e9 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -164,7 +164,7 @@ static void make_response(struct xen_blkif *blkif, u64 id,
 
 #define foreach_grant_safe(pos, n, rbtree, node) \
         for ((pos) = container_of(rb_first((rbtree)), typeof(*(pos)), node), \
-             (n) = rb_next(&(pos)->node); \
+             (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL; \
              &(pos)->node != NULL; \
              (pos) = container_of(n, typeof(*(pos)), node), \
              (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL)
@@ -381,8 +381,8 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id)
 
 static void print_stats(struct xen_blkif *blkif)
 {
-        pr_info("xen-blkback (%s): oo %3d  |  rd %4d  |  wr %4d  |  f %4d"
-                 "  |  ds %4d\n",
+        pr_info("xen-blkback (%s): oo %3llu  |  rd %4llu  |  wr %4llu  |  f %4llu"
+                 "  |  ds %4llu\n",
                  current->comm, blkif->st_oo_req,
                  blkif->st_rd_req, blkif->st_wr_req,
                  blkif->st_f_req, blkif->st_ds_req);
@@ -442,7 +442,7 @@ int xen_blkif_schedule(void *arg)
 }
 
 struct seg_buf {
-        unsigned long buf;
+        unsigned int offset;
         unsigned int nsec;
 };
 /*
@@ -621,30 +621,21 @@ static int xen_blkbk_map(struct blkif_request *req,
                                  * If this is a new persistent grant
                                  * save the handler
                                  */
-                                persistent_gnts[i]->handle = map[j].handle;
-                                persistent_gnts[i]->dev_bus_addr =
-                                        map[j++].dev_bus_addr;
+                                persistent_gnts[i]->handle = map[j++].handle;
                         }
                         pending_handle(pending_req, i) =
                                 persistent_gnts[i]->handle;
 
                         if (ret)
                                 continue;
-
-                        seg[i].buf = persistent_gnts[i]->dev_bus_addr |
-                                (req->u.rw.seg[i].first_sect << 9);
                 } else {
-                        pending_handle(pending_req, i) = map[j].handle;
+                        pending_handle(pending_req, i) = map[j++].handle;
                         bitmap_set(pending_req->unmap_seg, i, 1);
 
-                        if (ret) {
-                                j++;
+                        if (ret)
                                 continue;
-                        }
-
-                        seg[i].buf = map[j++].dev_bus_addr |
-                                (req->u.rw.seg[i].first_sect << 9);
                 }
+                seg[i].offset = (req->u.rw.seg[i].first_sect << 9);
         }
         return ret;
 }
@@ -679,6 +670,16 @@ static int dispatch_discard_io(struct xen_blkif *blkif,
         return err;
 }
 
+static int dispatch_other_io(struct xen_blkif *blkif,
+                             struct blkif_request *req,
+                             struct pending_req *pending_req)
+{
+        free_req(pending_req);
+        make_response(blkif, req->u.other.id, req->operation,
+                      BLKIF_RSP_EOPNOTSUPP);
+        return -EIO;
+}
+
 static void xen_blk_drain_io(struct xen_blkif *blkif)
 {
         atomic_set(&blkif->drain, 1);
@@ -800,17 +801,30 @@ __do_block_io_op(struct xen_blkif *blkif)
 
                 /* Apply all sanity checks to /private copy/ of request. */
                 barrier();
-                if (unlikely(req.operation == BLKIF_OP_DISCARD)) {
+
+                switch (req.operation) {
+                case BLKIF_OP_READ:
+                case BLKIF_OP_WRITE:
+                case BLKIF_OP_WRITE_BARRIER:
+                case BLKIF_OP_FLUSH_DISKCACHE:
+                        if (dispatch_rw_block_io(blkif, &req, pending_req))
+                                goto done;
+                        break;
+                case BLKIF_OP_DISCARD:
                         free_req(pending_req);
                         if (dispatch_discard_io(blkif, &req))
-                                break;
-                } else if (dispatch_rw_block_io(blkif, &req, pending_req))
+                                goto done;
                         break;
+                default:
+                        if (dispatch_other_io(blkif, &req, pending_req))
+                                goto done;
+                        break;
+                }
 
                 /* Yield point for this unbounded loop. */
                 cond_resched();
         }
-
+done:
         return more_to_do;
 }
 
@@ -904,7 +918,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
                 pr_debug(DRV_PFX "access denied: %s of [%llu,%llu] on dev=%04x\n",
                          operation == READ ? "read" : "write",
                          preq.sector_number,
-                         preq.sector_number + preq.nr_sects, preq.dev);
+                         preq.sector_number + preq.nr_sects,
+                         blkif->vbd.pdevice);
                 goto fail_response;
         }
 
@@ -947,7 +962,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
                        (bio_add_page(bio,
                                      pages[i],
                                      seg[i].nsec << 9,
-                                     seg[i].buf & ~PAGE_MASK) == 0)) {
+                                     seg[i].offset) == 0)) {
 
                         bio = bio_alloc(GFP_KERNEL, nseg-i);
                         if (unlikely(bio == NULL))
@@ -977,13 +992,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
                 bio->bi_end_io  = end_block_io_op;
         }
 
-        /*
-         * We set it one so that the last submit_bio does not have to call
-         * atomic_inc.
-         */
         atomic_set(&pending_req->pendcnt, nbio);
-
-        /* Get a reference count for the disk queue and start sending I/O */
         blk_start_plug(&plug);
 
         for (i = 0; i < nbio; i++)
@@ -1011,6 +1020,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
  fail_put_bio:
         for (i = 0; i < nbio; i++)
                 bio_put(biolist[i]);
+        atomic_set(&pending_req->pendcnt, 1);
         __end_block_io_op(pending_req, -EINVAL);
         msleep(1); /* back off a bit */
         return -EIO;
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index 6072390c7f57..60103e2517ba 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -77,11 +77,18 @@ struct blkif_x86_32_request_discard {
         uint64_t       nr_sectors;
 } __attribute__((__packed__));
 
+struct blkif_x86_32_request_other {
+        uint8_t        _pad1;
+        blkif_vdev_t   _pad2;
+        uint64_t       id;           /* private guest value, echoed in resp  */
+} __attribute__((__packed__));
+
 struct blkif_x86_32_request {
         uint8_t        operation;    /* BLKIF_OP_???                         */
         union {
                 struct blkif_x86_32_request_rw rw;
                 struct blkif_x86_32_request_discard discard;
+                struct blkif_x86_32_request_other other;
         } u;
 } __attribute__((__packed__));
 
@@ -113,11 +120,19 @@ struct blkif_x86_64_request_discard {
         uint64_t       nr_sectors;
 } __attribute__((__packed__));
 
+struct blkif_x86_64_request_other {
+        uint8_t        _pad1;
+        blkif_vdev_t   _pad2;
+        uint32_t       _pad3;        /* offsetof(blkif_..,u.discard.id)==8   */
+        uint64_t       id;           /* private guest value, echoed in resp  */
+} __attribute__((__packed__));
+
 struct blkif_x86_64_request {
         uint8_t        operation;    /* BLKIF_OP_???                         */
         union {
                 struct blkif_x86_64_request_rw rw;
                 struct blkif_x86_64_request_discard discard;
+                struct blkif_x86_64_request_other other;
         } u;
 } __attribute__((__packed__));
 
@@ -172,7 +187,6 @@ struct persistent_gnt {
         struct page *page;
         grant_ref_t gnt;
         grant_handle_t handle;
-        uint64_t dev_bus_addr;
         struct rb_node node;
 };
 
@@ -208,13 +222,13 @@ struct xen_blkif {
 
         /* statistics */
         unsigned long           st_print;
-        int                     st_rd_req;
-        int                     st_wr_req;
-        int                     st_oo_req;
-        int                     st_f_req;
-        int                     st_ds_req;
-        int                     st_rd_sect;
-        int                     st_wr_sect;
+        unsigned long long                      st_rd_req;
+        unsigned long long                      st_wr_req;
+        unsigned long long                      st_oo_req;
+        unsigned long long                      st_f_req;
+        unsigned long long                      st_ds_req;
+        unsigned long long                      st_rd_sect;
+        unsigned long long                      st_wr_sect;
 
         wait_queue_head_t       waiting_to_free;
 };
@@ -278,6 +292,11 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst,
                 dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
                 break;
         default:
+                /*
+                 * Don't know how to translate this op. Only get the
+                 * ID so failure can be reported to the frontend.
+                 */
+                dst->u.other.id = src->u.other.id;
                 break;
         }
 }
@@ -309,6 +328,11 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst,
                 dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
                 break;
         default:
+                /*
+                 * Don't know how to translate this op. Only get the
+                 * ID so failure can be reported to the frontend.
+                 */
+                dst->u.other.id = src->u.other.id;
                 break;
         }
 }
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 5e237f630c47..8bfd1bcf95ec 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -230,13 +230,13 @@ int __init xen_blkif_interface_init(void)
         }                                                               \
         static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 
-VBD_SHOW(oo_req,  "%d\n", be->blkif->st_oo_req);
-VBD_SHOW(rd_req,  "%d\n", be->blkif->st_rd_req);
-VBD_SHOW(wr_req,  "%d\n", be->blkif->st_wr_req);
-VBD_SHOW(f_req,  "%d\n", be->blkif->st_f_req);
-VBD_SHOW(ds_req,  "%d\n", be->blkif->st_ds_req);
-VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect);
-VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect);
+VBD_SHOW(oo_req,  "%llu\n", be->blkif->st_oo_req);
+VBD_SHOW(rd_req,  "%llu\n", be->blkif->st_rd_req);
+VBD_SHOW(wr_req,  "%llu\n", be->blkif->st_wr_req);
+VBD_SHOW(f_req,  "%llu\n", be->blkif->st_f_req);
+VBD_SHOW(ds_req,  "%llu\n", be->blkif->st_ds_req);
+VBD_SHOW(rd_sect, "%llu\n", be->blkif->st_rd_sect);
+VBD_SHOW(wr_sect, "%llu\n", be->blkif->st_wr_sect);
 
 static struct attribute *xen_vbdstat_attrs[] = {
         &dev_attr_oo_req.attr,