diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index e2ad6bba2281..9df516a56bb2 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -213,6 +213,7 @@ struct blkfront_info struct blk_mq_tag_set tag_set; struct blkfront_ring_info *rinfo; unsigned int nr_rings; + unsigned int rinfo_size; /* Save uncomplete reqs and bios for migration. */ struct list_head requests; struct bio_list bio_list; @@ -259,6 +260,18 @@ static int blkfront_setup_indirect(struct blkfront_ring_info *rinfo); static void blkfront_gather_backend_features(struct blkfront_info *info); static int negotiate_mq(struct blkfront_info *info); +#define for_each_rinfo(info, ptr, idx) \ + for ((ptr) = (info)->rinfo, (idx) = 0; \ + (idx) < (info)->nr_rings; \ + (idx)++, (ptr) = (void *)(ptr) + (info)->rinfo_size) + +static inline struct blkfront_ring_info * +get_rinfo(const struct blkfront_info *info, unsigned int i) +{ + BUG_ON(i >= info->nr_rings); + return (void *)info->rinfo + i * info->rinfo_size; +} + static int get_id_from_freelist(struct blkfront_ring_info *rinfo) { unsigned long free = rinfo->shadow_free; @@ -883,8 +896,7 @@ static blk_status_t blkif_queue_rq(struct blk_mq_hw_ctx *hctx, struct blkfront_info *info = hctx->queue->queuedata; struct blkfront_ring_info *rinfo = NULL; - BUG_ON(info->nr_rings <= qid); - rinfo = &info->rinfo[qid]; + rinfo = get_rinfo(info, qid); blk_mq_start_request(qd->rq); spin_lock_irqsave(&rinfo->ring_lock, flags); if (RING_FULL(&rinfo->ring)) @@ -1181,6 +1193,7 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity, static void xlvbd_release_gendisk(struct blkfront_info *info) { unsigned int minor, nr_minors, i; + struct blkfront_ring_info *rinfo; if (info->rq == NULL) return; @@ -1188,9 +1201,7 @@ static void xlvbd_release_gendisk(struct blkfront_info *info) /* No more blkif_request(). */ blk_mq_stop_hw_queues(info->rq); - for (i = 0; i < info->nr_rings; i++) { - struct blkfront_ring_info *rinfo = &info->rinfo[i]; - + for_each_rinfo(info, rinfo, i) { /* No more gnttab callback work. */ gnttab_cancel_free_callback(&rinfo->callback); @@ -1339,6 +1350,7 @@ free_shadow: static void blkif_free(struct blkfront_info *info, int suspend) { unsigned int i; + struct blkfront_ring_info *rinfo; /* Prevent new requests being issued until we fix things up. */ info->connected = suspend ? @@ -1347,8 +1359,8 @@ static void blkif_free(struct blkfront_info *info, int suspend) if (info->rq) blk_mq_stop_hw_queues(info->rq); - for (i = 0; i < info->nr_rings; i++) - blkif_free_ring(&info->rinfo[i]); + for_each_rinfo(info, rinfo, i) + blkif_free_ring(rinfo); kvfree(info->rinfo); info->rinfo = NULL; @@ -1775,6 +1787,7 @@ static int talk_to_blkback(struct xenbus_device *dev, int err; unsigned int i, max_page_order; unsigned int ring_page_order; + struct blkfront_ring_info *rinfo; if (!info) return -ENODEV; @@ -1788,9 +1801,7 @@ static int talk_to_blkback(struct xenbus_device *dev, if (err) goto destroy_blkring; - for (i = 0; i < info->nr_rings; i++) { - struct blkfront_ring_info *rinfo = &info->rinfo[i]; - + for_each_rinfo(info, rinfo, i) { /* Create shared ring, alloc event channel. */ err = setup_blkring(dev, rinfo); if (err) @@ -1815,7 +1826,7 @@ again: /* We already got the number of queues/rings in _probe */ if (info->nr_rings == 1) { - err = write_per_ring_nodes(xbt, &info->rinfo[0], dev->nodename); + err = write_per_ring_nodes(xbt, info->rinfo, dev->nodename); if (err) goto destroy_blkring; } else { @@ -1837,10 +1848,10 @@ again: goto abort_transaction; } - for (i = 0; i < info->nr_rings; i++) { + for_each_rinfo(info, rinfo, i) { memset(path, 0, pathsize); snprintf(path, pathsize, "%s/queue-%u", dev->nodename, i); - err = write_per_ring_nodes(xbt, &info->rinfo[i], path); + err = write_per_ring_nodes(xbt, rinfo, path); if (err) { kfree(path); goto destroy_blkring; @@ -1868,9 +1879,8 @@ again: goto destroy_blkring; } - for (i = 0; i < info->nr_rings; i++) { + for_each_rinfo(info, rinfo, i) { unsigned int j; - struct blkfront_ring_info *rinfo = &info->rinfo[i]; for (j = 0; j < BLK_RING_SIZE(info); j++) rinfo->shadow[j].req.u.rw.id = j + 1; @@ -1900,6 +1910,7 @@ static int negotiate_mq(struct blkfront_info *info) { unsigned int backend_max_queues; unsigned int i; + struct blkfront_ring_info *rinfo; BUG_ON(info->nr_rings); @@ -1911,20 +1922,16 @@ static int negotiate_mq(struct blkfront_info *info) if (!info->nr_rings) info->nr_rings = 1; - info->rinfo = kvcalloc(info->nr_rings, - struct_size(info->rinfo, shadow, - BLK_RING_SIZE(info)), - GFP_KERNEL); + info->rinfo_size = struct_size(info->rinfo, shadow, + BLK_RING_SIZE(info)); + info->rinfo = kvcalloc(info->nr_rings, info->rinfo_size, GFP_KERNEL); if (!info->rinfo) { xenbus_dev_fatal(info->xbdev, -ENOMEM, "allocating ring_info structure"); info->nr_rings = 0; return -ENOMEM; } - for (i = 0; i < info->nr_rings; i++) { - struct blkfront_ring_info *rinfo; - - rinfo = &info->rinfo[i]; + for_each_rinfo(info, rinfo, i) { INIT_LIST_HEAD(&rinfo->indirect_pages); INIT_LIST_HEAD(&rinfo->grants); rinfo->dev_info = info; @@ -2017,6 +2024,7 @@ static int blkif_recover(struct blkfront_info *info) int rc; struct bio *bio; unsigned int segs; + struct blkfront_ring_info *rinfo; blkfront_gather_backend_features(info); /* Reset limits changed by blk_mq_update_nr_hw_queues(). */ @@ -2024,9 +2032,7 @@ static int blkif_recover(struct blkfront_info *info) segs = info->max_indirect_segments ? : BLKIF_MAX_SEGMENTS_PER_REQUEST; blk_queue_max_segments(info->rq, segs / GRANTS_PER_PSEG); - for (r_index = 0; r_index < info->nr_rings; r_index++) { - struct blkfront_ring_info *rinfo = &info->rinfo[r_index]; - + for_each_rinfo(info, rinfo, r_index) { rc = blkfront_setup_indirect(rinfo); if (rc) return rc; @@ -2036,10 +2042,7 @@ static int blkif_recover(struct blkfront_info *info) /* Now safe for us to use the shared ring */ info->connected = BLKIF_STATE_CONNECTED; - for (r_index = 0; r_index < info->nr_rings; r_index++) { - struct blkfront_ring_info *rinfo; - - rinfo = &info->rinfo[r_index]; + for_each_rinfo(info, rinfo, r_index) { /* Kick any other new requests queued since we resumed */ kick_pending_request_queues(rinfo); } @@ -2072,13 +2075,13 @@ static int blkfront_resume(struct xenbus_device *dev) struct blkfront_info *info = dev_get_drvdata(&dev->dev); int err = 0; unsigned int i, j; + struct blkfront_ring_info *rinfo; 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]; + for_each_rinfo(info, rinfo, i) { struct bio_list merge_bio; struct blk_shadow *shadow = rinfo->shadow; @@ -2337,6 +2340,7 @@ static void blkfront_connect(struct blkfront_info *info) unsigned int binfo; char *envp[] = { "RESIZE=1", NULL }; int err, i; + struct blkfront_ring_info *rinfo; switch (info->connected) { case BLKIF_STATE_CONNECTED: @@ -2394,8 +2398,8 @@ static void blkfront_connect(struct blkfront_info *info) "physical-sector-size", sector_size); blkfront_gather_backend_features(info); - for (i = 0; i < info->nr_rings; i++) { - err = blkfront_setup_indirect(&info->rinfo[i]); + for_each_rinfo(info, rinfo, i) { + err = blkfront_setup_indirect(rinfo); if (err) { xenbus_dev_fatal(info->xbdev, err, "setup_indirect at %s", info->xbdev->otherend); @@ -2416,8 +2420,8 @@ static void blkfront_connect(struct blkfront_info *info) /* Kick pending requests. */ info->connected = BLKIF_STATE_CONNECTED; - for (i = 0; i < info->nr_rings; i++) - kick_pending_request_queues(&info->rinfo[i]); + for_each_rinfo(info, rinfo, i) + kick_pending_request_queues(rinfo); device_add_disk(&info->xbdev->dev, info->gd, NULL); @@ -2652,9 +2656,9 @@ static void purge_persistent_grants(struct blkfront_info *info) { unsigned int i; unsigned long flags; + struct blkfront_ring_info *rinfo; - for (i = 0; i < info->nr_rings; i++) { - struct blkfront_ring_info *rinfo = &info->rinfo[i]; + for_each_rinfo(info, rinfo, i) { struct grant *gnt_list_entry, *tmp; spin_lock_irqsave(&rinfo->ring_lock, flags); diff --git a/drivers/xen/xen-pciback/pciback.h b/drivers/xen/xen-pciback/pciback.h index ce1077e32466..7c95516a860f 100644 --- a/drivers/xen/xen-pciback/pciback.h +++ b/drivers/xen/xen-pciback/pciback.h @@ -52,7 +52,7 @@ struct xen_pcibk_dev_data { unsigned int ack_intr:1; /* .. and ACK-ing */ unsigned long handled; unsigned int irq; /* Saved in case device transitions to MSI/MSI-X */ - char irq_name[0]; /* xen-pcibk[000:04:00.0] */ + char irq_name[]; /* xen-pcibk[000:04:00.0] */ }; /* Used by XenBus and xen_pcibk_ops.c */ diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c index d239fc3c5e3d..eb5151fc8efa 100644 --- a/drivers/xen/xenbus/xenbus_comms.c +++ b/drivers/xen/xenbus/xenbus_comms.c @@ -313,6 +313,8 @@ static int process_msg(void) req->msg.type = state.msg.type; req->msg.len = state.msg.len; req->body = state.body; + /* write body, then update state */ + virt_wmb(); req->state = xb_req_state_got_reply; req->cb(req); } else @@ -395,6 +397,8 @@ static int process_writes(void) if (state.req->state == xb_req_state_aborted) kfree(state.req); else { + /* write err, then update state */ + virt_wmb(); state.req->state = xb_req_state_got_reply; wake_up(&state.req->wq); } diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index 66975da4f3b6..8c4d05b687b7 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -239,9 +239,9 @@ int xenbus_dev_probe(struct device *_dev) goto fail; } - spin_lock(&dev->reclaim_lock); + down(&dev->reclaim_sem); err = drv->probe(dev, id); - spin_unlock(&dev->reclaim_lock); + up(&dev->reclaim_sem); if (err) goto fail_put; @@ -271,9 +271,9 @@ int xenbus_dev_remove(struct device *_dev) free_otherend_watch(dev); if (drv->remove) { - spin_lock(&dev->reclaim_lock); + down(&dev->reclaim_sem); drv->remove(dev); - spin_unlock(&dev->reclaim_lock); + up(&dev->reclaim_sem); } module_put(drv->driver.owner); @@ -473,7 +473,7 @@ int xenbus_probe_node(struct xen_bus_type *bus, goto fail; dev_set_name(&xendev->dev, "%s", devname); - spin_lock_init(&xendev->reclaim_lock); + sema_init(&xendev->reclaim_sem, 1); /* Register with generic device framework. */ err = device_register(&xendev->dev); diff --git a/drivers/xen/xenbus/xenbus_probe_backend.c b/drivers/xen/xenbus/xenbus_probe_backend.c index 791f6fe01e91..9b2fbe69bccc 100644 --- a/drivers/xen/xenbus/xenbus_probe_backend.c +++ b/drivers/xen/xenbus/xenbus_probe_backend.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include @@ -257,10 +258,10 @@ static int backend_reclaim_memory(struct device *dev, void *data) drv = to_xenbus_driver(dev->driver); if (drv && drv->reclaim_memory) { xdev = to_xenbus_device(dev); - if (!spin_trylock(&xdev->reclaim_lock)) + if (down_trylock(&xdev->reclaim_sem)) return 0; drv->reclaim_memory(xdev); - spin_unlock(&xdev->reclaim_lock); + up(&xdev->reclaim_sem); } return 0; } diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index ddc18da61834..3a06eb699f33 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -191,8 +191,11 @@ static bool xenbus_ok(void) static bool test_reply(struct xb_req_data *req) { - if (req->state == xb_req_state_got_reply || !xenbus_ok()) + if (req->state == xb_req_state_got_reply || !xenbus_ok()) { + /* read req->state before all other fields */ + virt_rmb(); return true; + } /* Make sure to reread req->state each time. */ barrier(); @@ -202,7 +205,7 @@ static bool test_reply(struct xb_req_data *req) static void *read_reply(struct xb_req_data *req) { - while (req->state != xb_req_state_got_reply) { + do { wait_event(req->wq, test_reply(req)); if (!xenbus_ok()) @@ -216,7 +219,7 @@ static void *read_reply(struct xb_req_data *req) if (req->err) return ERR_PTR(req->err); - } + } while (req->state != xb_req_state_got_reply); return req->body; } diff --git a/include/xen/interface/io/tpmif.h b/include/xen/interface/io/tpmif.h index 28e7dcd75e82..f8aa8bac5196 100644 --- a/include/xen/interface/io/tpmif.h +++ b/include/xen/interface/io/tpmif.h @@ -46,7 +46,7 @@ struct vtpm_shared_page { uint8_t pad; uint8_t nr_extra_pages; /* extra pages for long packets; may be zero */ - uint32_t extra_pages[0]; /* grant IDs; length in nr_extra_pages */ + uint32_t extra_pages[]; /* grant IDs; length in nr_extra_pages */ }; #endif diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index 89a889585ba0..850a43bd69d3 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -42,6 +42,7 @@ #include #include #include +#include #include #include #include @@ -76,7 +77,7 @@ struct xenbus_device { enum xenbus_state state; struct completion down; struct work_struct work; - spinlock_t reclaim_lock; + struct semaphore reclaim_sem; }; static inline struct xenbus_device *to_xenbus_device(struct device *dev)