path: root/drivers/nvme/target/nvmet.h

/*
 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */

#ifndef _NVMET_H
#define _NVMET_H

#include <linux/dma-mapping.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/kref.h>
#include <linux/percpu-refcount.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/uuid.h>
#include <linux/nvme.h>
#include <linux/configfs.h>
#include <linux/rcupdate.h>
#include <linux/blkdev.h>
#include <linux/radix-tree.h>

#define NVMET_ASYNC_EVENTS		4
#define NVMET_ERROR_LOG_SLOTS		128
#define NVMET_NO_ERROR_LOC		((u16)-1)

/*
 * Supported optional AENs:
 */
#define NVMET_AEN_CFG_OPTIONAL \
	(NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_ANA_CHANGE)
#define NVMET_DISC_AEN_CFG_OPTIONAL \
	(NVME_AEN_CFG_DISC_CHANGE)

/*
 * Plus mandatory SMART AENs (we'll never send them, but allow enabling them):
 */
#define NVMET_AEN_CFG_ALL \
	(NVME_SMART_CRIT_SPARE | NVME_SMART_CRIT_TEMPERATURE | \
	 NVME_SMART_CRIT_RELIABILITY | NVME_SMART_CRIT_MEDIA | \
	 NVME_SMART_CRIT_VOLATILE_MEMORY | NVMET_AEN_CFG_OPTIONAL)

/* Helper Macros when NVMe error is NVME_SC_CONNECT_INVALID_PARAM
 * The 16 bit shift is to set IATTR bit to 1, which means offending
 * offset starts in the data section of connect()
 */
#define IPO_IATTR_CONNECT_DATA(x)	\
	(cpu_to_le32((1 << 16) | (offsetof(struct nvmf_connect_data, x))))
#define IPO_IATTR_CONNECT_SQE(x)	\
	(cpu_to_le32(offsetof(struct nvmf_connect_command, x)))

struct nvmet_ns {
	struct list_head	dev_link;
	struct percpu_ref	ref;
	struct block_device	*bdev;
	struct file		*file;
	bool			readonly;
	u32			nsid;
	u32			blksize_shift;
	loff_t			size;
	u8			nguid[16];
	uuid_t			uuid;
	u32			anagrpid;

	bool			buffered_io;
	bool			enabled;
	struct nvmet_subsys	*subsys;
	const char		*device_path;

	struct config_group	device_group;
	struct config_group	group;

	struct completion	disable_done;
	mempool_t		*bvec_pool;
	struct kmem_cache	*bvec_cache;

	int			use_p2pmem;
	struct pci_dev		*p2p_dev;
};

static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_ns, group);
}

static inline struct device *nvmet_ns_dev(struct nvmet_ns *ns)
{
	return ns->bdev ? disk_to_dev(ns->bdev->bd_disk) : NULL;
}

struct nvmet_cq {
	u16			qid;
	u16			size;
};

struct nvmet_sq {
	struct nvmet_ctrl	*ctrl;
	struct percpu_ref	ref;
	u16			qid;
	u16			size;
	u32			sqhd;
	bool			sqhd_disabled;
	struct completion	free_done;
	struct completion	confirm_done;
};

struct nvmet_ana_group {
	struct config_group	group;
	struct nvmet_port	*port;
	u32			grpid;
};

static inline struct nvmet_ana_group *to_ana_group(struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_ana_group,
			group);
}

/**
 * struct nvmet_port -	Common structure to keep port
 *				information for the target.
 * @entry:		Entry into referrals or transport list.
 * @disc_addr:		Address information is stored in a format defined
 *				for a discovery log page entry.
 * @group:		ConfigFS group for this element's folder.
 * @priv:		Private data for the transport.
 */
struct nvmet_port {
	struct list_head		entry;
	struct nvmf_disc_rsp_page_entry	disc_addr;
	struct config_group		group;
	struct config_group		subsys_group;
	struct list_head		subsystems;
	struct config_group		referrals_group;
	struct list_head		referrals;
	struct list_head		global_entry;
	struct config_group		ana_groups_group;
	struct nvmet_ana_group		ana_default_group;
	enum nvme_ana_state		*ana_state;
	void				*priv;
	bool				enabled;
	int				inline_data_size;
};

static inline struct nvmet_port *to_nvmet_port(struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_port,
			group);
}

static inline struct nvmet_port *ana_groups_to_port(
		struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_port,
			ana_groups_group);
}

struct nvmet_ctrl {
	struct nvmet_subsys	*subsys;
	struct nvmet_cq		**cqs;
	struct nvmet_sq		**sqs;

	bool			cmd_seen;

	struct mutex		lock;
	u64			cap;
	u32			cc;
	u32			csts;

	uuid_t			hostid;
	u16			cntlid;
	u32			kato;

	struct nvmet_port	*port;

	u32			aen_enabled;
	unsigned long		aen_masked;
	struct nvmet_req	*async_event_cmds[NVMET_ASYNC_EVENTS];
	unsigned int		nr_async_event_cmds;
	struct list_head	async_events;
	struct work_struct	async_event_work;

	struct list_head	subsys_entry;
	struct kref		ref;
	struct delayed_work	ka_work;
	struct work_struct	fatal_err_work;

	const struct nvmet_fabrics_ops *ops;

	__le32			*changed_ns_list;
	u32			nr_changed_ns;

	char			subsysnqn[NVMF_NQN_FIELD_LEN];
	char			hostnqn[NVMF_NQN_FIELD_LEN];

	struct device		*p2p_client;
	struct radix_tree_root	p2p_ns_map;

	spinlock_t		error_lock;
	u64			err_counter;
	struct nvme_error_slot	slots[NVMET_ERROR_LOG_SLOTS];
};

struct nvmet_subsys {
	enum nvme_subsys_type	type;

	struct mutex		lock;
	struct kref		ref;

	struct list_head	namespaces;
	unsigned int		nr_namespaces;
	unsigned int		max_nsid;

	struct list_head	ctrls;

	struct list_head	hosts;
	bool			allow_any_host;

	u16			max_qid;

	u64			ver;
	u64			serial;
	char			*subsysnqn;

	struct config_group	group;

	struct config_group	namespaces_group;
	struct config_group	allowed_hosts_group;
};

static inline struct nvmet_subsys *to_subsys(struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_subsys, group);
}

static inline struct nvmet_subsys *namespaces_to_subsys(
		struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_subsys,
			namespaces_group);
}

struct nvmet_host {
	struct config_group	group;
};

static inline struct nvmet_host *to_host(struct config_item *item)
{
	return container_of(to_config_group(item), struct nvmet_host, group);
}

static inline char *nvmet_host_name(struct nvmet_host *host)
{
	return config_item_name(&host->group.cg_item);
}

struct nvmet_host_link {
	struct list_head	entry;
	struct nvmet_host	*host;
};

struct nvmet_subsys_link {
	struct list_head	entry;
	struct nvmet_subsys	*subsys;
};

struct nvmet_req;
struct nvmet_fabrics_ops {
	struct module *owner;
	unsigned int type;
	unsigned int msdbd;
	bool has_keyed_sgls : 1;
	void (*queue_response)(struct nvmet_req *req);
	int (*add_port)(struct nvmet_port *port);
	void (*remove_port)(struct nvmet_port *port);
	void (*delete_ctrl)(struct nvmet_ctrl *ctrl);
	void (*disc_traddr)(struct nvmet_req *req,
			struct nvmet_port *port, char *traddr);
	u16 (*install_queue)(struct nvmet_sq *nvme_sq);
};

#define NVMET_MAX_INLINE_BIOVEC	8
#define NVMET_MAX_INLINE_DATA_LEN NVMET_MAX_INLINE_BIOVEC * PAGE_SIZE

struct nvmet_req {
	struct nvme_command	*cmd;
	struct nvme_completion	*rsp;
	struct nvmet_sq		*sq;
	struct nvmet_cq		*cq;
	struct nvmet_ns		*ns;
	struct scatterlist	*sg;
	struct bio_vec		inline_bvec[NVMET_MAX_INLINE_BIOVEC];
	union {
		struct {
			struct bio      inline_bio;
		} b;
		struct {
			bool			mpool_alloc;
			struct kiocb            iocb;
			struct bio_vec          *bvec;
			struct