xref: /linux/drivers/nvdimm/virtio_pmem.h (revision c79c3c34f75d72a066e292b10aa50fc758c97c89)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * virtio_pmem.h: virtio pmem Driver
4  *
5  * Discovers persistent memory range information
6  * from host and provides a virtio based flushing
7  * interface.
8  **/
9 
10 #ifndef _LINUX_VIRTIO_PMEM_H
11 #define _LINUX_VIRTIO_PMEM_H
12 
13 #include <linux/module.h>
14 #include <uapi/linux/virtio_pmem.h>
15 #include <linux/libnvdimm.h>
16 #include <linux/spinlock.h>
17 
18 struct virtio_pmem_request {
19 	struct virtio_pmem_req req;
20 	struct virtio_pmem_resp resp;
21 
22 	/* Wait queue to process deferred work after ack from host */
23 	wait_queue_head_t host_acked;
24 	bool done;
25 
26 	/* Wait queue to process deferred work after virt queue buffer avail */
27 	wait_queue_head_t wq_buf;
28 	bool wq_buf_avail;
29 	struct list_head list;
30 };
31 
32 struct virtio_pmem {
33 	struct virtio_device *vdev;
34 
35 	/* Virtio pmem request queue */
36 	struct virtqueue *req_vq;
37 
38 	/* nvdimm bus registers virtio pmem device */
39 	struct nvdimm_bus *nvdimm_bus;
40 	struct nvdimm_bus_descriptor nd_desc;
41 
42 	/* List to store deferred work if virtqueue is full */
43 	struct list_head req_list;
44 
45 	/* Synchronize virtqueue data */
46 	spinlock_t pmem_lock;
47 
48 	/* Memory region information */
49 	__u64 start;
50 	__u64 size;
51 };
52 
53 void virtio_pmem_host_ack(struct virtqueue *vq);
54 int async_pmem_flush(struct nd_region *nd_region, struct bio *bio);
55 #endif
56