xref: /linux/drivers/nvdimm/virtio_pmem.h (revision c17ee635fd3a482b2ad2bf5e269755c2eae5f25e)
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/mutex.h>
17 #include <linux/spinlock.h>
18 
19 struct virtio_pmem_request {
20 	struct virtio_pmem_req req;
21 	struct virtio_pmem_resp resp;
22 
23 	/* Wait queue to process deferred work after ack from host */
24 	wait_queue_head_t host_acked;
25 	bool done;
26 
27 	/* Wait queue to process deferred work after virt queue buffer avail */
28 	wait_queue_head_t wq_buf;
29 	bool wq_buf_avail;
30 	struct list_head list;
31 };
32 
33 struct virtio_pmem {
34 	struct virtio_device *vdev;
35 
36 	/* Virtio pmem request queue */
37 	struct virtqueue *req_vq;
38 
39 	/* Serialize flush requests to the device. */
40 	struct mutex flush_lock;
41 
42 	/* nvdimm bus registers virtio pmem device */
43 	struct nvdimm_bus *nvdimm_bus;
44 	struct nvdimm_bus_descriptor nd_desc;
45 
46 	/* List to store deferred work if virtqueue is full */
47 	struct list_head req_list;
48 
49 	/* Synchronize virtqueue data */
50 	spinlock_t pmem_lock;
51 
52 	/* Memory region information */
53 	__u64 start;
54 	__u64 size;
55 };
56 
57 void virtio_pmem_host_ack(struct virtqueue *vq);
58 int async_pmem_flush(struct nd_region *nd_region, struct bio *bio);
59 #endif
60