1 files changed, 105 insertions, 67 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index aff789d6fcc..c421fa52851 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -937,12 +937,14 @@ static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
 					u64 snap_id)
 {
 	u32 which;
+	const char *snap_name;
 
 	which = rbd_dev_snap_index(rbd_dev, snap_id);
 	if (which == BAD_SNAP_INDEX)
-		return NULL;
+		return ERR_PTR(-ENOENT);
 
-	return _rbd_dev_v1_snap_name(rbd_dev, which);
+	snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
+	return snap_name ? snap_name : ERR_PTR(-ENOMEM);
 }
 
 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
@@ -1126,6 +1128,7 @@ static void zero_bio_chain(struct bio *chain, int start_ofs)
 				buf = bvec_kmap_irq(bv, &flags);
 				memset(buf + remainder, 0,
 				       bv->bv_len - remainder);
+				flush_dcache_page(bv->bv_page);
 				bvec_kunmap_irq(buf, &flags);
 			}
 			pos += bv->bv_len;
@@ -1158,6 +1161,7 @@ static void zero_pages(struct page **pages, u64 offset, u64 end)
 		local_irq_save(flags);
 		kaddr = kmap_atomic(*page);
 		memset(kaddr + page_offset, 0, length);
+		flush_dcache_page(*page);
 		kunmap_atomic(kaddr);
 		local_irq_restore(flags);
 
@@ -1565,11 +1569,12 @@ rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
 		obj_request, obj_request->img_request, obj_request->result,
 		xferred, length);
 	/*
-	 * ENOENT means a hole in the image.  We zero-fill the
-	 * entire length of the request.  A short read also implies
-	 * zero-fill to the end of the request.  Either way we
-	 * update the xferred count to indicate the whole request
-	 * was satisfied.
+	 * ENOENT means a hole in the image.  We zero-fill the entire
+	 * length of the request.  A short read also implies zero-fill
+	 * to the end of the request.  An error requires the whole
+	 * length of the request to be reported finished with an error
+	 * to the block layer.  In each case we update the xferred
+	 * count to indicate the whole request was satisfied.
 	 */
 	rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
 	if (obj_request->result == -ENOENT) {
@@ -1578,14 +1583,13 @@ rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
 		else
 			zero_pages(obj_request->pages, 0, length);
 		obj_request->result = 0;
-		obj_request->xferred = length;
 	} else if (xferred < length && !obj_request->result) {
 		if (obj_request->type == OBJ_REQUEST_BIO)
 			zero_bio_chain(obj_request->bio_list, xferred);
 		else
 			zero_pages(obj_request->pages, xferred, length);
-		obj_request->xferred = length;
 	}
+	obj_request->xferred = length;
 	obj_request_done_set(obj_request);
 }
 
@@ -2171,9 +2175,9 @@ static int rbd_img_request_fill(struct rbd_img_request *img_request,
 	struct rbd_obj_request *obj_request = NULL;
 	struct rbd_obj_request *next_obj_request;
 	bool write_request = img_request_write_test(img_request);
-	struct bio *bio_list;
+	struct bio *bio_list = 0;
 	unsigned int bio_offset = 0;
-	struct page **pages;
+	struct page **pages = 0;
 	u64 img_offset;
 	u64 resid;
 	u16 opcode;
@@ -2211,6 +2215,11 @@ static int rbd_img_request_fill(struct rbd_img_request *img_request,
 		rbd_segment_name_free(object_name);
 		if (!obj_request)
 			goto out_unwind;
+		/*
+		 * set obj_request->img_request before creating the
+		 * osd_request so that it gets the right snapc
+		 */
+		rbd_img_obj_request_add(img_request, obj_request);
 
 		if (type == OBJ_REQUEST_BIO) {
 			unsigned int clone_size;
@@ -2252,11 +2261,6 @@ static int rbd_img_request_fill(struct rbd_img_request *img_request,
 					obj_request->pages, length,
 					offset & ~PAGE_MASK, false, false);
 
-		/*
-		 * set obj_request->img_request before formatting
-		 * the osd_request so that it gets the right snapc
-		 */
-		rbd_img_obj_request_add(img_request, obj_request);
 		if (write_request)
 			rbd_osd_req_format_write(obj_request);
 		else
@@ -2817,7 +2821,7 @@ out_err:
 	obj_request_done_set(obj_request);
 }
 
-static int rbd_obj_notify_ack(struct rbd_device *rbd_dev, u64 notify_id)
+static int rbd_obj_notify_ack_sync(struct rbd_device *rbd_dev, u64 notify_id)
 {
 	struct rbd_obj_request *obj_request;
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
@@ -2832,16 +2836,17 @@ static int rbd_obj_notify_ack(struct rbd_device *rbd_dev, u64 notify_id)
 	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
 	if (!obj_request->osd_req)
 		goto out;
-	obj_request->callback = rbd_obj_request_put;
 
 	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
 					notify_id, 0, 0);
 	rbd_osd_req_format_read(obj_request);
 
 	ret = rbd_obj_request_submit(osdc, obj_request);
-out:
 	if (ret)
-		rbd_obj_request_put(obj_request);
+		goto out;
+	ret = rbd_obj_request_wait(obj_request);
+out:
+	rbd_obj_request_put(obj_request);
 
 	return ret;
 }
@@ -2861,7 +2866,7 @@ static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
 	if (ret)
 		rbd_warn(rbd_dev, ": header refresh error (%d)\n", ret);
 
-	rbd_obj_notify_ack(rbd_dev, notify_id);
+	rbd_obj_notify_ack_sync(rbd_dev, notify_id);
 }
 
 /*
@@ -3333,6 +3338,31 @@ static void rbd_exists_validate(struct rbd_device *rbd_dev)
 		clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
 }
 
+static void rbd_dev_update_size(struct rbd_device *rbd_dev)
+{
+	sector_t size;
+	bool removing;
+
+	/*
+	 * Don't hold the lock while doing disk operations,
+	 * or lock ordering will conflict with the bdev mutex via:
+	 * rbd_add() -> blkdev_get() -> rbd_open()
+	 */
+	spin_lock_irq(&rbd_dev->lock);
+	removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
+	spin_unlock_irq(&rbd_dev->lock);
+	/*
+	 * If the device is being removed, rbd_dev->disk has
+	 * been destroyed, so don't try to update its size
+	 */
+	if (!removing) {
+		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
+		dout("setting size to %llu sectors", (unsigned long long)size);
+		set_capacity(rbd_dev->disk, size);
+		revalidate_disk(rbd_dev->disk);
+	}
+}
+
 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
 {
 	u64 mapping_size;
@@ -3351,12 +3381,7 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
 	rbd_exists_validate(rbd_dev);
 	mutex_unlock(&ctl_mutex);
 	if (mapping_size != rbd_dev->mapping.size) {
-		sector_t size;
-
-		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
-		dout("setting size to %llu sectors", (unsigned long long)size);
-		set_capacity(rbd_dev->disk, size);
-		revalidate_disk(rbd_dev->disk);
+		rbd_dev_update_size(rbd_dev);
 	}
 
 	return ret;
@@ -3710,12 +3735,14 @@ static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
 	if (ret < sizeof (size_buf))
 		return -ERANGE;
 
-	if (order)
+	if (order) {
 		*order = size_buf.order;
+		dout("  order %u", (unsigned int)*order);
+	}
 	*snap_size = le64_to_cpu(size_buf.size);
 
-	dout("  snap_id 0x%016llx order = %u, snap_size = %llu\n",
-		(unsigned long long)snap_id, (unsigned int)*order,
+	dout("  snap_id 0x%016llx snap_size = %llu\n",
+		(unsigned long long)snap_id,
 		(unsigned long long)*snap_size);
 
 	return 0;
@@ -4030,8 +4057,13 @@ static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
 
 		snap_id = snapc->snaps[which];
 		snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
-		if (IS_ERR(snap_name))
-			break;
+		if (IS_ERR(snap_name)) {
+			/* ignore no-longer existing snapshots */
+			if (PTR_ERR(snap_name) == -ENOENT)
+				continue;
+			else
+				break;
+		}
 		found = !strcmp(name, snap_name);
 		kfree(snap_name);
 	}
@@ -4110,8 +4142,8 @@ static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
 	/* Look up the snapshot name, and make a copy */
 
 	snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
-	if (!snap_name) {
-		ret = -ENOMEM;
+	if (IS_ERR(snap_name)) {
+		ret = PTR_ERR(snap_name);
 		goto out_err;
 	}
 
@@ -5059,23 +5091,6 @@ err_out_module:
 	return (ssize_t)rc;
 }
 
-static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
-{
-	struct list_head *tmp;
-	struct rbd_device *rbd_dev;
-
-	spin_lock(&rbd_dev_list_lock);
-	list_for_each(tmp, &rbd_dev_list) {
-		rbd_dev = list_entry(tmp, struct rbd_device, node);
-		if (rbd_dev->dev_id == dev_id) {
-			spin_unlock(&rbd_dev_list_lock);
-			return rbd_dev;
-		}
-	}
-	spin_unlock(&rbd_dev_list_lock);
-	return NULL;
-}
-
 static void rbd_dev_device_release(struct device *dev)
 {
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
@@ -5120,8 +5135,10 @@ static ssize_t rbd_remove(struct bus_type *bus,
 			  size_t count)
 {
 	struct rbd_device *rbd_dev = NULL;
-	int target_id;
+	struct list_head *tmp;
+	int dev_id;
 	unsigned long ul;
+	bool already = false;
 	int ret;
 
 	ret = strict_strtoul(buf, 10, &ul);
@@ -5129,30 +5146,51 @@ static ssize_t rbd_remove(struct bus_type *bus,
 		return ret;
 
 	/* convert to int; abort if we lost anything in the conversion */
-	target_id = (int) ul;
-	if (target_id != ul)
+	dev_id = (int)ul;
+	if (dev_id != ul)
 		return -EINVAL;
 
 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
-	rbd_dev = __rbd_get_dev(target_id);
-	if (!rbd_dev) {
-		ret = -ENOENT;
-		goto done;
+	ret = -ENOENT;
+	spin_lock(&rbd_dev_list_lock);
+	list_for_each(tmp, &rbd_dev_list) {
+		rbd_dev = list_entry(tmp, struct rbd_device, node);
+		if (rbd_dev->dev_id == dev_id) {
+			ret = 0;
+			break;
+		}
 	}
-
-	spin_lock_irq(&rbd_dev->lock);
-	if (rbd_dev->open_count)
-		ret = -EBUSY;
-	else
-		set_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
-	spin_unlock_irq(&rbd_dev->lock);
-	if (ret < 0)
+	if (!ret) {
+		spin_lock_irq(&rbd_dev->lock);
+		if (rbd_dev->open_count)
+			ret = -EBUSY;
+		else
+			already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
+							&rbd_dev->flags);
+		spin_unlock_irq(&rbd_dev->lock);
+	}
+	spin_unlock(&rbd_dev_list_lock);
+	if (ret < 0 || already)
 		goto done;
-	rbd_bus_del_dev(rbd_dev);
+
 	ret = rbd_dev_header_watch_sync(rbd_dev, false);
 	if (ret)
 		rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
+
+	/*
+	 * flush remaining watch callbacks - these must be complete
+	 * before the osd_client is shutdown
+	 */
+	dout("%s: flushing notifies", __func__);
+	ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
+	/*
+	 * Don't free anything from rbd_dev->disk until after all
+	 * notifies are completely processed. Otherwise
+	 * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting
+	 * in a potential use after free of rbd_dev->disk or rbd_dev.
+	 */
+	rbd_bus_del_dev(rbd_dev);
 	rbd_dev_image_release(rbd_dev);
 	module_put(THIS_MODULE);
 	ret = count;