Merge branch 'stable/for-jens-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git...

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 2e6d1e9..fcc5b4e 100644 (file)
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -207,6 +207,9 @@ struct blkfront_info
        struct blk_mq_tag_set tag_set;
        struct blkfront_ring_info *rinfo;
        unsigned int nr_rings;
+       /* Save uncomplete reqs and bios for migration. */
+       struct list_head requests;
+       struct bio_list bio_list;
 };
 
 static unsigned int nr_minors;
@@ -2002,69 +2005,22 @@ static int blkif_recover(struct blkfront_info *info)
 {
        unsigned int i, r_index;
        struct request *req, *n;
-       struct blk_shadow *copy;
        int rc;
        struct bio *bio, *cloned_bio;
-       struct bio_list bio_list, merge_bio;
        unsigned int segs, offset;
        int pending, size;
        struct split_bio *split_bio;
-       struct list_head requests;
 
        blkfront_gather_backend_features(info);
        segs = info->max_indirect_segments ? : BLKIF_MAX_SEGMENTS_PER_REQUEST;
        blk_queue_max_segments(info->rq, segs);
-       bio_list_init(&bio_list);
-       INIT_LIST_HEAD(&requests);
 
        for (r_index = 0; r_index < info->nr_rings; r_index++) {
-               struct blkfront_ring_info *rinfo;
-
-               rinfo = &info->rinfo[r_index];
-               /* Stage 1: Make a safe copy of the shadow state. */
-               copy = kmemdup(rinfo->shadow, sizeof(rinfo->shadow),
-                              GFP_NOIO | __GFP_REPEAT | __GFP_HIGH);
-               if (!copy)
-                       return -ENOMEM;
-
-               /* Stage 2: Set up free list. */
-               memset(&rinfo->shadow, 0, sizeof(rinfo->shadow));
-               for (i = 0; i < BLK_RING_SIZE(info); i++)
-                       rinfo->shadow[i].req.u.rw.id = i+1;
-               rinfo->shadow_free = rinfo->ring.req_prod_pvt;
-               rinfo->shadow[BLK_RING_SIZE(info)-1].req.u.rw.id = 0x0fffffff;
+               struct blkfront_ring_info *rinfo = &info->rinfo[r_index];
 
                rc = blkfront_setup_indirect(rinfo);
-               if (rc) {
-                       kfree(copy);
+               if (rc)
                        return rc;
-               }
-
-               for (i = 0; i < BLK_RING_SIZE(info); i++) {
-                       /* Not in use? */
-                       if (!copy[i].request)
-                               continue;
-
-                       /*
-                        * Get the bios in the request so we can re-queue them.
-                        */
-                       if (copy[i].request->cmd_flags &
-                           (REQ_FLUSH | REQ_FUA | REQ_DISCARD | REQ_SECURE)) {
-                               /*
-                                * Flush operations don't contain bios, so
-                                * we need to requeue the whole request
-                                */
-                               list_add(&copy[i].request->queuelist, &requests);
-                               continue;
-                       }
-                       merge_bio.head = copy[i].request->bio;
-                       merge_bio.tail = copy[i].request->biotail;
-                       bio_list_merge(&bio_list, &merge_bio);
-                       copy[i].request->bio = NULL;
-                       blk_end_request_all(copy[i].request, 0);
-               }
-
-               kfree(copy);
        }
        xenbus_switch_state(info->xbdev, XenbusStateConnected);
 
@@ -2079,7 +2035,7 @@ static int blkif_recover(struct blkfront_info *info)
                kick_pending_request_queues(rinfo);
        }
 
-       list_for_each_entry_safe(req, n, &requests, queuelist) {
+       list_for_each_entry_safe(req, n, &info->requests, queuelist) {
                /* Requeue pending requests (flush or discard) */
                list_del_init(&req->queuelist);
                BUG_ON(req->nr_phys_segments > segs);
@@ -2087,7 +2043,7 @@ static int blkif_recover(struct blkfront_info *info)
        }
        blk_mq_kick_requeue_list(info->rq);
 
-       while ((bio = bio_list_pop(&bio_list)) != NULL) {
+       while ((bio = bio_list_pop(&info->bio_list)) != NULL) {
                /* Traverse the list of pending bios and re-queue them */
                if (bio_segments(bio) > segs) {
                        /*
@@ -2133,9 +2089,42 @@ static int blkfront_resume(struct xenbus_device *dev)
 {
        struct blkfront_info *info = dev_get_drvdata(&dev->dev);
        int err = 0;
+       unsigned int i, j;
 
        dev_dbg(&dev->dev, "blkfront_resume: %s\n", dev->nodename);
 
+       bio_list_init(&info->bio_list);
+       INIT_LIST_HEAD(&info->requests);
+       for (i = 0; i < info->nr_rings; i++) {
+               struct blkfront_ring_info *rinfo = &info->rinfo[i];
+               struct bio_list merge_bio;
+               struct blk_shadow *shadow = rinfo->shadow;
+
+               for (j = 0; j < BLK_RING_SIZE(info); j++) {
+                       /* Not in use? */
+                       if (!shadow[j].request)
+                               continue;
+
+                       /*
+                        * Get the bios in the request so we can re-queue them.
+                        */
+                       if (shadow[j].request->cmd_flags &
+                                       (REQ_FLUSH | REQ_FUA | REQ_DISCARD | REQ_SECURE)) {
+                               /*
+                                * Flush operations don't contain bios, so
+                                * we need to requeue the whole request
+                                */
+                               list_add(&shadow[j].request->queuelist, &info->requests);
+                               continue;
+                       }
+                       merge_bio.head = shadow[j].request->bio;
+                       merge_bio.tail = shadow[j].request->biotail;
+                       bio_list_merge(&info->bio_list, &merge_bio);
+                       shadow[j].request->bio = NULL;
+                       blk_mq_end_request(shadow[j].request, 0);
+               }
+       }
+
        blkif_free(info, info->connected == BLKIF_STATE_CONNECTED);
 
        err = negotiate_mq(info);