Spdk/lib/bdev/ocf/vbdev_ocf.h

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#ifndef SPDK_VBDEV_OCF_H
#define SPDK_VBDEV_OCF_H

#include <ocf/ocf.h>

#include "spdk/bdev.h"
#include "spdk/bdev_module.h"

struct vbdev_ocf;

/* Context for OCF queue poller
 * Used for mapping SPDK threads to OCF queues */
struct vbdev_ocf_qcxt {
	/* OCF queue. Contains OCF requests */
	struct ocf_queue            *queue;
	/* Poller for OCF queue. Runs OCF requests */
	struct spdk_poller          *poller;
	/* Reference to parent vbdev */
	struct vbdev_ocf            *vbdev;
	/* Base devices channels */
	struct spdk_io_channel      *cache_ch;
	struct spdk_io_channel      *core_ch;
	/* Link to per-bdev list of queue contexts */
	TAILQ_ENTRY(vbdev_ocf_qcxt)  tailq;
};

/* Important states */
struct vbdev_ocf_state {
	/* From the moment when finish started */
	bool                         doing_finish;
	/* From the moment when reset IO recieved, until it is completed */
	bool                         doing_reset;
	/* From the moment when exp_bdev is registered */
	bool                         started;
};

/*
 * OCF cache configuration options
 */
struct vbdev_ocf_config {
	/* Initial cache configuration  */
	struct ocf_mngt_cache_config        cache;

	/* Cache device config */
	struct ocf_mngt_cache_device_config device;

	/* Core initial config */
	struct ocf_mngt_core_config         core;
};

/* Base device info */
struct vbdev_ocf_base {
	/* OCF unique internal id */
	int                          id;

	/* OCF internal name */
	char                        *name;

	/* True if this is a caching device */
	bool                         is_cache;

	/* Connected SPDK block device */
	struct spdk_bdev            *bdev;

	/* SPDK device io handle */
	struct spdk_bdev_desc       *desc;

	/* True if SPDK bdev has been claimed and opened for writing */
	bool                         attached;

	/* Reference to main vbdev */
	struct vbdev_ocf            *parent;
};

/*
 * The main information provider
 * It's also registered as io_device
 */
struct vbdev_ocf {
	/* Exposed unique name */
	char                        *name;

	/* Base bdevs */
	struct vbdev_ocf_base        cache;
	struct vbdev_ocf_base        core;

	/* Base bdevs OCF objects */
	ocf_cache_t                  ocf_cache;
	ocf_core_t                   ocf_core;

	/* Parameters */
	struct vbdev_ocf_config      cfg;
	struct vbdev_ocf_state       state;

	/* Exposed SPDK bdev. Registered in bdev layer */
	struct spdk_bdev             exp_bdev;

	/* Link to global list of this type structures */
	TAILQ_ENTRY(vbdev_ocf)       tailq;

	/* List of queues contexts
	 * New items are added at io_channel creation */
	TAILQ_HEAD(, vbdev_ocf_qcxt) queues;

	/* Private per-bdev lock */
	pthread_mutex_t              _lock;
};

int vbdev_ocf_construct(
	const char *vbdev_name,
	const char *cache_mode_name,
	const char *cache_name,
	const char *core_name);

/* If vbdev is online, return its object */
struct vbdev_ocf *vbdev_ocf_get_by_name(const char *name);

/* Return matching base if parent vbdev is online */
struct vbdev_ocf_base *vbdev_ocf_get_base_by_name(const char *name);

/* Stop OCF cache and unregister SPDK bdev */
int vbdev_ocf_delete(struct vbdev_ocf *vbdev);

#endif