include/linux/lightnvm.h

#ifndef NVM_H
#define NVM_H

enum {
	NVM_IO_OK = 0,
	NVM_IO_REQUEUE = 1,
	NVM_IO_DONE = 2,
	NVM_IO_ERR = 3,

	NVM_IOTYPE_NONE = 0,
	NVM_IOTYPE_GC = 1,
};

#ifdef CONFIG_NVM

#include <linux/blkdev.h>
#include <linux/types.h>
#include <linux/file.h>
#include <linux/dmapool.h>

enum {
	/* HW Responsibilities */
	NVM_RSP_L2P	= 1 << 0,
	NVM_RSP_ECC	= 1 << 1,

	/* Physical Adressing Mode */
	NVM_ADDRMODE_LINEAR	= 0,
	NVM_ADDRMODE_CHANNEL	= 1,

	/* Plane programming mode for LUN */
	NVM_PLANE_SINGLE	= 0,
	NVM_PLANE_DOUBLE	= 1,
	NVM_PLANE_QUAD		= 2,

	/* Status codes */
	NVM_RSP_SUCCESS		= 0x0,
	NVM_RSP_NOT_CHANGEABLE	= 0x1,
	NVM_RSP_ERR_FAILWRITE	= 0x40ff,
	NVM_RSP_ERR_EMPTYPAGE	= 0x42ff,

	/* Device opcodes */
	NVM_OP_HBREAD		= 0x02,
	NVM_OP_HBWRITE		= 0x81,
	NVM_OP_PWRITE		= 0x91,
	NVM_OP_PREAD		= 0x92,
	NVM_OP_ERASE		= 0x90,

	/* PPA Command Flags */
	NVM_IO_SNGL_ACCESS	= 0x0,
	NVM_IO_DUAL_ACCESS	= 0x1,
	NVM_IO_QUAD_ACCESS	= 0x2,

	NVM_IO_SUSPEND		= 0x80,
	NVM_IO_SLC_MODE		= 0x100,
	NVM_IO_SCRAMBLE_DISABLE	= 0x200,
};

struct nvm_id_group {
	u8	mtype;
	u8	fmtype;
	u8	num_ch;
	u8	num_lun;
	u8	num_pln;
	u16	num_blk;
	u16	num_pg;
	u16	fpg_sz;
	u16	csecs;
	u16	sos;
	u32	trdt;
	u32	trdm;
	u32	tprt;
	u32	tprm;
	u32	tbet;
	u32	tbem;
	u32	mpos;
	u32	mccap;
	u16	cpar;
};

struct nvm_addr_format {
	u8	ch_offset;
	u8	ch_len;
	u8	lun_offset;
	u8	lun_len;
	u8	pln_offset;
	u8	pln_len;
	u8	blk_offset;
	u8	blk_len;
	u8	pg_offset;
	u8	pg_len;
	u8	sect_offset;
	u8	sect_len;
};

struct nvm_id {
	u8	ver_id;
	u8	vmnt;
	u8	cgrps;
	u32	cap;
	u32	dom;
	struct nvm_addr_format ppaf;
	struct nvm_id_group groups[4];
} __packed;

struct nvm_target {
	struct list_head list;
	struct nvm_tgt_type *type;
	struct gendisk *disk;
};

struct nvm_tgt_instance {
	struct nvm_tgt_type *tt;
};

#define ADDR_EMPTY (~0ULL)

#define NVM_VERSION_MAJOR 1
#define NVM_VERSION_MINOR 0
#define NVM_VERSION_PATCH 0

#define NVM_BLK_BITS (16)
#define NVM_PG_BITS  (16)
#define NVM_SEC_BITS (8)
#define NVM_PL_BITS  (8)
#define NVM_LUN_BITS (8)
#define NVM_CH_BITS  (8)

struct ppa_addr {
	/* Generic structure for all addresses */
	union {
		struct {
			u64 blk		: NVM_BLK_BITS;
			u64 pg		: NVM_PG_BITS;
			u64 sec		: NVM_SEC_BITS;
			u64 pl		: NVM_PL_BITS;
			u64 lun		: NVM_LUN_BITS;
			u64 ch		: NVM_CH_BITS;
		} g;

		u64 ppa;
	};
};

struct nvm_rq {
	struct nvm_tgt_instance *ins;
	struct nvm_dev *dev;

	struct bio *bio;

	union {
		struct ppa_addr ppa_addr;
		dma_addr_t dma_ppa_list;
	};

	struct ppa_addr *ppa_list;

	void *metadata;
	dma_addr_t dma_metadata;

	uint8_t opcode;
	uint16_t nr_pages;
	uint16_t flags;
};

static inline struct nvm_rq *nvm_rq_from_pdu(void *pdu)
{
	return pdu - sizeof(struct nvm_rq);
}

static inline void *nvm_rq_to_pdu(struct nvm_rq *rqdata)
{
	return rqdata + 1;
}

struct nvm_block;

typedef int (nvm_l2p_update_fn)(u64, u32, __le64 *, void *);
typedef int (nvm_bb_update_fn)(struct ppa_addr, int, u8 *, void *);
typedef int (nvm_id_fn)(struct request_queue *, struct nvm_id *);
typedef int (nvm_get_l2p_tbl_fn)(struct request_queue *, u64, u32,
				nvm_l2p_update_fn *, void *);
typedef int (nvm_op_bb_tbl_fn)(struct request_queue *, struct ppa_addr, int,
				nvm_bb_update_fn *, void *);
typedef int (nvm_op_set_bb_fn)(struct request_queue *, struct nvm_rq *, int);
typedef int (nvm_submit_io_fn)(struct request_queue *, struct nvm_rq *);
typedef int (nvm_erase_blk_fn)(struct request_queue *, struct nvm_rq *);
typedef void *(nvm_create_dma_pool_fn)(struct request_queue *, char *);
typedef void (nvm_destroy_dma_pool_fn)(void *);
typedef void *(nvm_dev_dma_alloc_fn)(struct request_queue *, void *, gfp_t,
								dma_addr_t *);
typedef void (nvm_dev_dma_free_fn)(void *, void*, dma_addr_t);

struct nvm_dev_ops {
	nvm_id_fn		*identity;
	nvm_get_l2p_tbl_fn	*get_l2p_tbl;
	nvm_op_bb_tbl_fn	*get_bb_tbl;
	nvm_op_set_bb_fn	*set_bb_tbl;

	nvm_submit_io_fn	*submit_io;
	nvm_erase_blk_fn	*erase_block;

	nvm_create_dma_pool_fn	*create_dma_pool;
	nvm_destroy_dma_pool_fn	*destroy_dma_pool;
	nvm_dev_dma_alloc_fn	*dev_dma_alloc;
	nvm_dev_dma_free_fn	*dev_dma_free;

	unsigned int		max_phys_sect;
};

struct nvm_lun {
	int id;

	int lun_id;
	int chnl_id;

	unsigned int nr_inuse_blocks;	/* Number of used blocks */
	unsigned int nr_free_blocks;	/* Number of unused blocks */
	unsigned int nr_bad_blocks;	/* Number of bad blocks */
	struct nvm_block *blocks;

	spinlock_t lock;
};

struct nvm_block {
	struct list_head list;
	struct nvm_lun *lun;
	unsigned long id;

	void *priv;
	int type;
};

struct nvm_dev {
	struct nvm_dev_ops *ops;

	struct list_head devices;
	struct list_head online_targets;

	/* Media manager */
	struct nvmm_type *mt;
	void *mp;

	/* Device information */
	int nr_chnls;
	int nr_planes;
	int luns_per_chnl;
	int sec_per_pg; /* only sectors for a single page */
	int pgs_per_blk;
	int blks_per_lun;
	int sec_size;
	int oob_size;
	struct nvm_addr_format ppaf;

	/* Calculated/Cached values. These do not reflect the actual usable
	 * blocks at run-time.
	 */
	int max_rq_size;
	int plane_mode; /* drive device in single, double or quad mode */

	int sec_per_pl; /* all sectors across planes */
	int sec_per_blk;
	int sec_per_lun;

	unsigned long total_pages;
	unsigned long total_blocks;
	int nr_luns;
	unsigned max_pages_per_blk;

	void *ppalist_pool;

	struct nvm_id identity;

	/* Backend device */
	struct request_queue *q;
	char name[DISK_NAME_LEN];
};

static inline struct ppa_addr generic_to_dev_addr(struct nvm_dev *dev,
						struct ppa_addr r)
{
	struct ppa_addr l;

	l.ppa = ((u64)r.g.blk) << dev->ppaf.blk_offset;
	l.ppa |= ((u64)r.g.pg) << dev->ppaf.pg_offset;
	l.ppa |= ((u64)r.g.sec) << dev->ppaf.sect_offset;
	l.ppa |= ((u64)r.g.pl) << dev->ppaf.pln_offset;
	l.ppa |= ((u64)r.g.lun) << dev->ppaf.lun_offset;
	l.ppa |= ((u64)r.g.ch) << dev->ppaf.ch_offset;

	return l;
}

static inline struct ppa_addr dev_to_generic_addr(struct nvm_dev *dev,
						struct ppa_addr r)
{
	struct ppa_addr l;

	/*
	 * (r.ppa << X offset) & X len bitmask. X eq. blk, pg, etc.
	 */
	l.g.blk = (r.ppa >> dev->ppaf.blk_offset) &
					(((1 << dev->ppaf.blk_len) - 1));
	l.g.pg |= (r.ppa >> dev->ppaf.pg_offset) &
					(((1 << dev->ppaf.pg_len) - 1));
	l.g.sec |= (r.ppa >> dev->ppaf.sect_offset) &
					(((1 << dev->ppaf.sect_len) - 1));
	l.g.pl |= (r.ppa >> dev->ppaf.pln_offset) &
					(((1 << dev->ppaf.pln_len) - 1));
	l.g.lun |= (r.ppa >> dev->ppaf.lun_offset) &
					(((1 << dev->ppaf.lun_len) - 1));
	l.g.ch |= (r.ppa >> dev->ppaf.ch_offset) &
					(((1 << dev->ppaf.ch_len) - 1));

	return l;
}

static inline int ppa_empty(struct ppa_addr ppa_addr)
{
	return (ppa_addr.ppa == ADDR_EMPTY);
}

static inline void ppa_set_empty(struct ppa_addr *ppa_addr)
{
	ppa_addr->ppa = ADDR_EMPTY;
}

static inline struct ppa_addr block_to_ppa(struct nvm_dev *dev,
							struct nvm_block *blk)
{
	struct ppa_addr ppa;
	struct nvm_lun *lun = blk->lun;

	ppa.ppa = 0;
	ppa.g.blk = blk->id % dev->blks_per_lun;
	ppa.g.lun = lun->lun_id;
	ppa.g.ch = lun->chnl_id;

	return ppa;
}

typedef blk_qc_t (nvm_tgt_make_rq_fn)(struct request_queue *, struct bio *);
typedef sector_t (nvm_tgt_capacity_fn)(void *);
typedef int (nvm_tgt_end_io_fn)(struct nvm_rq *, int);
typedef void *(nvm_tgt_init_fn)(struct nvm_dev *, struct gendisk *, int, int);
typedef void (nvm_tgt_exit_fn)(void *);

struct nvm_tgt_type {
	const char *name;
	unsigned int version[3];

	/* target entry points */
	nvm_tgt_make_rq_fn *make_rq;
	nvm_tgt_capacity_fn *capacity;
	nvm_tgt_end_io_fn *end_io;

	/* module-specific init/teardown */
	nvm_tgt_init_fn *init;
	nvm_tgt_exit_fn *exit;

	/* For internal use */
	struct list_head list;
};

extern int nvm_register_target(struct nvm_tgt_type *);
extern void nvm_unregister_target(struct nvm_tgt_type *);

extern void *nvm_dev_dma_alloc(struct nvm_dev *, gfp_t, dma_addr_t *);
extern void nvm_dev_dma_free(struct nvm_dev *, void *, dma_addr_t);

typedef int (nvmm_register_fn)(struct nvm_dev *);
typedef void (nvmm_unregister_fn)(struct nvm_dev *);
typedef struct nvm_block *(nvmm_get_blk_fn)(struct nvm_dev *,
					      struct nvm_lun *, unsigned long);
typedef void (nvmm_put_blk_fn)(struct nvm_dev *, struct nvm_block *);
typedef int (nvmm_open_blk_fn)(struct nvm_dev *, struct nvm_block *);
typedef int (nvmm_close_blk_fn)(struct nvm_dev *, struct nvm_block *);
typedef void (nvmm_flush_blk_fn)(struct nvm_dev *, struct nvm_block *);
typedef int (nvmm_submit_io_fn)(struct nvm_dev *, struct nvm_rq *);
typedef int (nvmm_end_io_fn)(struct nvm_rq *, int);
typedef int (nvmm_erase_blk_fn)(struct nvm_dev *, struct nvm_block *,
								unsigned long);
typedef struct nvm_lun *(nvmm_get_lun_fn)(struct nvm_dev *, int);
typedef void (nvmm_free_blocks_print_fn)(struct nvm_dev *);

struct nvmm_type {
	const char *name;
	unsigned int version[3];

	nvmm_register_fn *register_mgr;
	nvmm_unregister_fn *unregister_mgr;

	/* Block administration callbacks */
	nvmm_get_blk_fn *get_blk;
	nvmm_put_blk_fn *put_blk;
	nvmm_open_blk_fn *open_blk;
	nvmm_close_blk_fn *close_blk;
	nvmm_flush_blk_fn *flush_blk;

	nvmm_submit_io_fn *submit_io;
	nvmm_end_io_fn *end_io;
	nvmm_erase_blk_fn *erase_blk;

	/* Configuration management */
	nvmm_get_lun_fn *get_lun;

	/* Statistics */
	nvmm_free_blocks_print_fn *free_blocks_print;
	struct list_head list;
};

extern int nvm_register_mgr(struct nvmm_type *);
extern void nvm_unregister_mgr(struct nvmm_type *);

extern struct nvm_block *nvm_get_blk(struct nvm_dev *, struct nvm_lun *,
								unsigned long);
extern void nvm_put_blk(struct nvm_dev *, struct nvm_block *);

extern int nvm_register(struct request_queue *, char *,
						struct nvm_dev_ops *);
extern void nvm_unregister(char *);

extern int nvm_submit_io(struct nvm_dev *, struct nvm_rq *);
extern int nvm_erase_blk(struct nvm_dev *, struct nvm_block *);
#else /* CONFIG_NVM */
struct nvm_dev_ops;

static inline int nvm_register(struct request_queue *q, char *disk_name,
							struct nvm_dev_ops *ops)
{
	return -EINVAL;
}
static inline void nvm_unregister(char *disk_name) {}
#endif /* CONFIG_NVM */
#endif /* LIGHTNVM.H */