text: #ifndef NVM_H
  #define NVM_H
  
  #include <linux/blkdev.h>
  #include <linux/types.h>
  #include <uapi/linux/lightnvm.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,
  };
  
  #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  (7)
  
  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;
  			u64 reserved	: 1;
  		} g;
  
  		struct {
  			u64 line	: 63;
  			u64 is_cached	: 1;
  		} c;
  
  		u64 ppa;
  	};
  };
  
  struct nvm_rq;
  struct nvm_id;
  struct nvm_dev;
  
  typedef int (nvm_l2p_update_fn)(u64, u32, __le64 *, void *);
  typedef int (nvm_id_fn)(struct nvm_dev *, struct nvm_id *);
  typedef int (nvm_get_l2p_tbl_fn)(struct nvm_dev *, u64, u32,
  				nvm_l2p_update_fn *, void *);
  typedef int (nvm_op_bb_tbl_fn)(struct nvm_dev *, struct ppa_addr, u8 *);
  typedef int (nvm_op_set_bb_fn)(struct nvm_dev *, struct ppa_addr *, int, int);
  typedef int (nvm_submit_io_fn)(struct nvm_dev *, struct nvm_rq *);
  typedef int (nvm_erase_blk_fn)(struct nvm_dev *, struct nvm_rq *);
  typedef void *(nvm_create_dma_pool_fn)(struct nvm_dev *, char *);
  typedef void (nvm_destroy_dma_pool_fn)(void *);
  typedef void *(nvm_dev_dma_alloc_fn)(struct nvm_dev *, 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;
  };
  
  
  
  #ifdef CONFIG_NVM
  
  #include <linux/blkdev.h>
  #include <linux/file.h>
  #include <linux/dmapool.h>
  #include <uapi/linux/lightnvm.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	= 1,
  	NVM_PLANE_DOUBLE	= 2,
  	NVM_PLANE_QUAD		= 4,
  
  	/* 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,
  
  	/* NAND Access Modes */
  	NVM_IO_SUSPEND		= 0x80,
  	NVM_IO_SLC_MODE		= 0x100,
  	NVM_IO_SCRAMBLE_DISABLE	= 0x200,
  
  	/* Block Types */
  	NVM_BLK_T_FREE		= 0x0,
  	NVM_BLK_T_BAD		= 0x1,
  	NVM_BLK_T_GRWN_BAD	= 0x2,
  	NVM_BLK_T_DEV		= 0x4,
  	NVM_BLK_T_HOST		= 0x8,
  
  	/* Memory capabilities */
  	NVM_ID_CAP_SLC		= 0x1,
  	NVM_ID_CAP_CMD_SUSPEND	= 0x2,
  	NVM_ID_CAP_SCRAMBLE	= 0x4,
  	NVM_ID_CAP_ENCRYPT	= 0x8,
  
  	/* Memory types */
  	NVM_ID_FMTYPE_SLC	= 0,
  	NVM_ID_FMTYPE_MLC	= 1,
  
  	/* Device capabilities */
  	NVM_ID_DCAP_BBLKMGMT	= 0x1,
  	NVM_UD_DCAP_ECC		= 0x2,
  };
  
  struct nvm_id_lp_mlc {
  	u16	num_pairs;
  	u8	pairs[886];
  };
  
  struct nvm_id_lp_tbl {
  	__u8	id[8];
  	struct nvm_id_lp_mlc mlc;
  };
  
  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_id_lp_tbl lptbl;
  };
  
  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_dev *dev;
  	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
  
  struct nvm_rq;
  typedef void (nvm_end_io_fn)(struct nvm_rq *);
  
  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 *meta_list;
  	dma_addr_t dma_meta_list;
  
  	struct completion *wait;
  	nvm_end_io_fn *end_io;
  
  	uint8_t opcode;
  	uint16_t nr_ppas;
  	uint16_t flags;
  
  	u64 ppa_status; /* ppa media status */
  	int error;
  };
  
  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;
  
  struct nvm_lun {
  	int id;
  
  	int lun_id;
  	int chnl_id;
  
  	spinlock_t lock;
  
  	unsigned int nr_free_blocks;	/* Number of unused blocks */
  	struct nvm_block *blocks;
  };
  
  enum {
  	NVM_BLK_ST_FREE =	0x1,	/* Free block */
  	NVM_BLK_ST_TGT =	0x2,	/* Block in use by target */
  	NVM_BLK_ST_BAD =	0x8,	/* Bad block */
  };
  
  struct nvm_block {
  	struct list_head list;
  	struct nvm_lun *lun;
  	unsigned long id;
  
  	void *priv;
  	int state;
  };
  
  /* system block cpu representation */
  struct nvm_sb_info {
  	unsigned long		seqnr;
  	unsigned long		erase_cnt;
  	unsigned int		version;
  	char			mmtype[NVM_MMTYPE_LEN];
  	struct ppa_addr		fs_ppa;
  };
  
  struct nvm_dev {
  	struct nvm_dev_ops *ops;
  
  	struct list_head devices;
  
  	/* Media manager */
  	struct nvmm_type *mt;
  	void *mp;
  
  	/* System blocks */
  	struct nvm_sb_info sb;
  
  	/* 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 fpg_size;
  	int pfpg_size; /* size of buffer if all pages are to be read */
  	int sec_size;
  	int oob_size;
  	int mccap;
  	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;
  
  	/* lower page table */
  	int lps_per_blk;
  	int *lptbl;
  
  	unsigned long total_blocks;
  	unsigned long total_secs;
  	int nr_luns;
  
  	unsigned long *lun_map;
  	void *dma_pool;
  
  	struct nvm_id identity;
  
  	/* Backend device */
  	struct request_queue *q;
  	struct device dev;
  	struct device *parent_dev;
  	char name[DISK_NAME_LEN];
  	void *private_data;
  
  	struct mutex mlock;
  	spinlock_t lock;
  };
  
  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;
  
  	l.ppa = 0;
  	/*
  	 * (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;
  }
  
  static inline int ppa_to_slc(struct nvm_dev *dev, int slc_pg)
  {
  	return dev->lptbl[slc_pg];
  }
  
  typedef blk_qc_t (nvm_tgt_make_rq_fn)(struct request_queue *, struct bio *);
  typedef sector_t (nvm_tgt_capacity_fn)(void *);
  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_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 struct nvm_tgt_type *nvm_find_target_type(const char *, int);
  
  extern int nvm_register_tgt_type(struct nvm_tgt_type *);
  extern void nvm_unregister_tgt_type(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 int (nvmm_create_tgt_fn)(struct nvm_dev *, struct nvm_ioctl_create *);
  typedef int (nvmm_remove_tgt_fn)(struct nvm_dev *, struct nvm_ioctl_remove *);
  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_erase_blk_fn)(struct nvm_dev *, struct nvm_block *,
  								unsigned long);
  typedef void (nvmm_mark_blk_fn)(struct nvm_dev *, struct ppa_addr, int);
  typedef struct nvm_lun *(nvmm_get_lun_fn)(struct nvm_dev *, int);
  typedef int (nvmm_reserve_lun)(struct nvm_dev *, int);
  typedef void (nvmm_release_lun)(struct nvm_dev *, int);
  typedef void (nvmm_lun_info_print_fn)(struct nvm_dev *);
  
  typedef int (nvmm_get_area_fn)(struct nvm_dev *, sector_t *, sector_t);
  typedef void (nvmm_put_area_fn)(struct nvm_dev *, sector_t);
  
  struct nvmm_type {
  	const char *name;
  	unsigned int version[3];
  
  	nvmm_register_fn *register_mgr;
  	nvmm_unregister_fn *unregister_mgr;
  
  	nvmm_create_tgt_fn *create_tgt;
  	nvmm_remove_tgt_fn *remove_tgt;
  
  	/* 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_erase_blk_fn *erase_blk;
  
  	/* Bad block mgmt */
  	nvmm_mark_blk_fn *mark_blk;
  
  	/* Configuration management */
  	nvmm_get_lun_fn *get_lun;
  	nvmm_reserve_lun *reserve_lun;
  	nvmm_release_lun *release_lun;
  
  	/* Statistics */
  	nvmm_lun_info_print_fn *lun_info_print;
  
  	nvmm_get_area_fn *get_area;
  	nvmm_put_area_fn *put_area;
  
  	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 struct nvm_dev *nvm_alloc_dev(int);
  extern int nvm_register(struct nvm_dev *);
  extern void nvm_unregister(struct nvm_dev *);
  
  void nvm_mark_blk(struct nvm_dev *dev, struct ppa_addr ppa, int type);
  
  extern int nvm_submit_io(struct nvm_dev *, struct nvm_rq *);
  extern void nvm_generic_to_addr_mode(struct nvm_dev *, struct nvm_rq *);
  extern void nvm_addr_to_generic_mode(struct nvm_dev *, struct nvm_rq *);
  extern int nvm_set_rqd_ppalist(struct nvm_dev *, struct nvm_rq *,
  					const struct ppa_addr *, int, int);
  extern void nvm_free_rqd_ppalist(struct nvm_dev *, struct nvm_rq *);
  extern int nvm_erase_ppa(struct nvm_dev *, struct ppa_addr *, int);
  extern int nvm_erase_blk(struct nvm_dev *, struct nvm_block *);
  extern void nvm_end_io(struct nvm_rq *, int);
  extern int nvm_submit_ppa(struct nvm_dev *, struct ppa_addr *, int, int, int,
  								void *, int);
  extern int nvm_submit_ppa_list(struct nvm_dev *, struct ppa_addr *, int, int,
  							int, void *, int);
  extern int nvm_bb_tbl_fold(struct nvm_dev *, u8 *, int);
  extern int nvm_get_bb_tbl(struct nvm_dev *, struct ppa_addr, u8 *);
  
  /* sysblk.c */
  #define NVM_SYSBLK_MAGIC 0x4E564D53 /* "NVMS" */
  
  /* system block on disk representation */
  struct nvm_system_block {
  	__be32			magic;		/* magic signature */
  	__be32			seqnr;		/* sequence number */
  	__be32			erase_cnt;	/* erase count */
  	__be16			version;	/* version number */
  	u8			mmtype[NVM_MMTYPE_LEN]; /* media manager name */
  	__be64			fs_ppa;		/* PPA for media manager
  						 * superblock */
  };
  
  extern int nvm_get_sysblock(struct nvm_dev *, struct nvm_sb_info *);
  extern int nvm_update_sysblock(struct nvm_dev *, struct nvm_sb_info *);
  extern int nvm_init_sysblock(struct nvm_dev *, struct nvm_sb_info *);
  
  extern int nvm_dev_factory(struct nvm_dev *, int flags);
  
  #define nvm_for_each_lun_ppa(dev, ppa, chid, lunid)			\
  	for ((chid) = 0, (ppa).ppa = 0; (chid) < (dev)->nr_chnls;	\
  					(chid)++, (ppa).g.ch = (chid))	\
  		for ((lunid) = 0; (lunid) < (dev)->luns_per_chnl;	\
  					(lunid)++, (ppa).g.lun = (lunid))
  
  #else /* CONFIG_NVM */
  struct nvm_dev_ops;
  
  static inline struct nvm_dev *nvm_alloc_dev(int node)
  {
  	return ERR_PTR(-EINVAL);
  }
  static inline int nvm_register(struct nvm_dev *dev)
  {
  	return -EINVAL;
  }
  static inline void nvm_unregister(struct nvm_dev *dev) {}
  #endif /* CONFIG_NVM */
  #endif /* LIGHTNVM.H */
  