[mirror_ubuntu-artful-kernel.git] / drivers / nvdimm / btt.h

/*
 * Block Translation Table library
 * Copyright (c) 2014-2015, Intel Corporation.
 *
 * 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 _LINUX_BTT_H
#define _LINUX_BTT_H

#include <linux/badblocks.h>
#include <linux/types.h>

#define BTT_SIG_LEN 16
#define BTT_SIG "BTT_ARENA_INFO\0"
#define MAP_ENT_SIZE 4
#define MAP_TRIM_SHIFT 31
#define MAP_TRIM_MASK (1 << MAP_TRIM_SHIFT)
#define MAP_ERR_SHIFT 30
#define MAP_ERR_MASK (1 << MAP_ERR_SHIFT)
#define MAP_LBA_MASK (~((1 << MAP_TRIM_SHIFT) | (1 << MAP_ERR_SHIFT)))
#define MAP_ENT_NORMAL 0xC0000000
#define LOG_ENT_SIZE sizeof(struct log_entry)
#define ARENA_MIN_SIZE (1UL << 24)	/* 16 MB */
#define ARENA_MAX_SIZE (1ULL << 39)	/* 512 GB */
#define RTT_VALID (1UL << 31)
#define RTT_INVALID 0
#define BTT_PG_SIZE 4096
#define BTT_DEFAULT_NFREE ND_MAX_LANES
#define LOG_SEQ_INIT 1

#define IB_FLAG_ERROR 0x00000001
#define IB_FLAG_ERROR_MASK 0x00000001

#define ent_lba(ent) (ent & MAP_LBA_MASK)
#define ent_e_flag(ent) (!!(ent & MAP_ERR_MASK))
#define ent_z_flag(ent) (!!(ent & MAP_TRIM_MASK))
#define set_e_flag(ent) (ent |= MAP_ERR_MASK)

enum btt_init_state {
	INIT_UNCHECKED = 0,
	INIT_NOTFOUND,
	INIT_READY
};

struct log_entry {
	__le32 lba;
	__le32 old_map;
	__le32 new_map;
	__le32 seq;
	__le64 padding[2];
};

struct btt_sb {
	u8 signature[BTT_SIG_LEN];
	u8 uuid[16];
	u8 parent_uuid[16];
	__le32 flags;
	__le16 version_major;
	__le16 version_minor;
	__le32 external_lbasize;
	__le32 external_nlba;
	__le32 internal_lbasize;
	__le32 internal_nlba;
	__le32 nfree;
	__le32 infosize;
	__le64 nextoff;
	__le64 dataoff;
	__le64 mapoff;
	__le64 logoff;
	__le64 info2off;
	u8 padding[3968];
	__le64 checksum;
};

struct free_entry {
	u32 block;
	u8 sub;
	u8 seq;
	u8 has_err;
};

struct aligned_lock {
	union {
		spinlock_t lock;
		u8 cacheline_padding[L1_CACHE_BYTES];
	};
};

/**
 * struct arena_info - handle for an arena
 * @size:		Size in bytes this arena occupies on the raw device.
 *			This includes arena metadata.
 * @external_lba_start:	The first external LBA in this arena.
 * @internal_nlba:	Number of internal blocks available in the arena
 *			including nfree reserved blocks
 * @internal_lbasize:	Internal and external lba sizes may be different as
 *			we can round up 'odd' external lbasizes such as 520B
 *			to be aligned.
 * @external_nlba:	Number of blocks contributed by the arena to the number
 *			reported to upper layers. (internal_nlba - nfree)
 * @external_lbasize:	LBA size as exposed to upper layers.
 * @nfree:		A reserve number of 'free' blocks that is used to
 *			handle incoming writes.
 * @version_major:	Metadata layout version major.
 * @version_minor:	Metadata layout version minor.
 * @sector_size:	The Linux sector size - 512 or 4096
 * @nextoff:		Offset in bytes to the start of the next arena.
 * @infooff:		Offset in bytes to the info block of this arena.
 * @dataoff:		Offset in bytes to the data area of this arena.
 * @mapoff:		Offset in bytes to the map area of this arena.
 * @logoff:		Offset in bytes to the log area of this arena.
 * @info2off:		Offset in bytes to the backup info block of this arena.
 * @freelist:		Pointer to in-memory list of free blocks
 * @rtt:		Pointer to in-memory "Read Tracking Table"
 * @map_locks:		Spinlocks protecting concurrent map writes
 * @nd_btt:		Pointer to parent nd_btt structure.
 * @list:		List head for list of arenas
 * @debugfs_dir:	Debugfs dentry
 * @flags:		Arena flags - may signify error states.
 *
 * arena_info is a per-arena handle. Once an arena is narrowed down for an
 * IO, this struct is passed around for the duration of the IO.
 */
struct arena_info {
	u64 size;			/* Total bytes for this arena */
	u64 external_lba_start;
	u32 internal_nlba;
	u32 internal_lbasize;
	u32 external_nlba;
	u32 external_lbasize;
	u32 nfree;
	u16 version_major;
	u16 version_minor;
	u32 sector_size;
	/* Byte offsets to the different on-media structures */
	u64 nextoff;
	u64 infooff;
	u64 dataoff;
	u64 mapoff;
	u64 logoff;
	u64 info2off;
	/* Pointers to other in-memory structures for this arena */
	struct free_entry *freelist;
	u32 *rtt;
	struct aligned_lock *map_locks;
	struct nd_btt *nd_btt;
	struct list_head list;
	struct dentry *debugfs_dir;
	/* Arena flags */
	u32 flags;
	struct mutex err_lock;
};

/**
 * struct btt - handle for a BTT instance
 * @btt_disk:		Pointer to the gendisk for BTT device
 * @btt_queue:		Pointer to the request queue for the BTT device
 * @arena_list:		Head of the list of arenas
 * @debugfs_dir:	Debugfs dentry
 * @nd_btt:		Parent nd_btt struct
 * @nlba:		Number of logical blocks exposed to the	upper layers
 *			after removing the amount of space needed by metadata
 * @rawsize:		Total size in bytes of the available backing device
 * @lbasize:		LBA size as requested and presented to upper layers.
 *			This is sector_size + size of any metadata.
 * @sector_size:	The Linux sector size - 512 or 4096
 * @lanes:		Per-lane spinlocks
 * @init_lock:		Mutex used for the BTT initialization
 * @init_state:		Flag describing the initialization state for the BTT
 * @num_arenas:		Number of arenas in the BTT instance
 */
struct btt {
	struct gendisk *btt_disk;
	struct request_queue *btt_queue;
	struct list_head arena_list;
	struct dentry *debugfs_dir;
	struct nd_btt *nd_btt;
	u64 nlba;
	unsigned long long rawsize;
	u32 lbasize;
	u32 sector_size;
	struct nd_region *nd_region;
	struct mutex init_lock;
	int init_state;
	int num_arenas;
	struct badblocks *phys_bb;
};

bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super);
int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
		struct btt_sb *btt_sb);

#endif
Commit	Line	Data
8c2f7e86 DW	1	/*
	2	* Block Translation Table library
	3	* Copyright (c) 2014-2015, Intel Corporation.
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms and conditions of the GNU General Public License,
	7	* version 2, as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope it will be useful, but WITHOUT
	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	12	* more details.
	13	*/
	14
	15	#ifndef _LINUX_BTT_H
	16	#define _LINUX_BTT_H
	17
ebaccf71	18	#include <linux/badblocks.h>
8c2f7e86 DW	19	#include <linux/types.h>
	20
	21	#define BTT_SIG_LEN 16
	22	#define BTT_SIG "BTT_ARENA_INFO\0"
5212e11f VV	23	#define MAP_ENT_SIZE 4
	24	#define MAP_TRIM_SHIFT 31
	25	#define MAP_TRIM_MASK (1 << MAP_TRIM_SHIFT)
	26	#define MAP_ERR_SHIFT 30
	27	#define MAP_ERR_MASK (1 << MAP_ERR_SHIFT)
	28	#define MAP_LBA_MASK (~((1 << MAP_TRIM_SHIFT) \| (1 << MAP_ERR_SHIFT)))
	29	#define MAP_ENT_NORMAL 0xC0000000
	30	#define LOG_ENT_SIZE sizeof(struct log_entry)
	31	#define ARENA_MIN_SIZE (1UL << 24) /* 16 MB */
	32	#define ARENA_MAX_SIZE (1ULL << 39) /* 512 GB */
	33	#define RTT_VALID (1UL << 31)
	34	#define RTT_INVALID 0
5212e11f VV	35	#define BTT_PG_SIZE 4096
	36	#define BTT_DEFAULT_NFREE ND_MAX_LANES
	37	#define LOG_SEQ_INIT 1
	38
	39	#define IB_FLAG_ERROR 0x00000001
	40	#define IB_FLAG_ERROR_MASK 0x00000001
	41
45f43c23 VV	42	#define ent_lba(ent) (ent & MAP_LBA_MASK)
	43	#define ent_e_flag(ent) (!!(ent & MAP_ERR_MASK))
	44	#define ent_z_flag(ent) (!!(ent & MAP_TRIM_MASK))
ebaccf71	45	#define set_e_flag(ent) (ent \|= MAP_ERR_MASK)
45f43c23	46
5212e11f VV	47	enum btt_init_state {
	48	INIT_UNCHECKED = 0,
	49	INIT_NOTFOUND,
	50	INIT_READY
	51	};
	52
	53	struct log_entry {
	54	__le32 lba;
	55	__le32 old_map;
	56	__le32 new_map;
	57	__le32 seq;
	58	__le64 padding[2];
	59	};
8c2f7e86 DW	60
	61	struct btt_sb {
	62	u8 signature[BTT_SIG_LEN];
	63	u8 uuid[16];
	64	u8 parent_uuid[16];
	65	__le32 flags;
	66	__le16 version_major;
	67	__le16 version_minor;
	68	__le32 external_lbasize;
	69	__le32 external_nlba;
	70	__le32 internal_lbasize;
	71	__le32 internal_nlba;
	72	__le32 nfree;
	73	__le32 infosize;
	74	__le64 nextoff;
	75	__le64 dataoff;
	76	__le64 mapoff;
	77	__le64 logoff;
	78	__le64 info2off;
	79	u8 padding[3968];
	80	__le64 checksum;
	81	};
	82
5212e11f VV	83	struct free_entry {
	84	u32 block;
	85	u8 sub;
	86	u8 seq;
ebaccf71	87	u8 has_err;
5212e11f VV	88	};
	89
	90	struct aligned_lock {
	91	union {
	92	spinlock_t lock;
	93	u8 cacheline_padding[L1_CACHE_BYTES];
	94	};
	95	};
	96
	97	/**
	98	* struct arena_info - handle for an arena
	99	* @size: Size in bytes this arena occupies on the raw device.
	100	* This includes arena metadata.
	101	* @external_lba_start: The first external LBA in this arena.
	102	* @internal_nlba: Number of internal blocks available in the arena
	103	* including nfree reserved blocks
	104	* @internal_lbasize: Internal and external lba sizes may be different as
	105	* we can round up 'odd' external lbasizes such as 520B
	106	* to be aligned.
	107	* @external_nlba: Number of blocks contributed by the arena to the number
	108	* reported to upper layers. (internal_nlba - nfree)
	109	* @external_lbasize: LBA size as exposed to upper layers.
	110	* @nfree: A reserve number of 'free' blocks that is used to
	111	* handle incoming writes.
	112	* @version_major: Metadata layout version major.
	113	* @version_minor: Metadata layout version minor.
adfc036d	114	* @sector_size: The Linux sector size - 512 or 4096
5212e11f VV	115	* @nextoff: Offset in bytes to the start of the next arena.
	116	* @infooff: Offset in bytes to the info block of this arena.
	117	* @dataoff: Offset in bytes to the data area of this arena.
	118	* @mapoff: Offset in bytes to the map area of this arena.
	119	* @logoff: Offset in bytes to the log area of this arena.
	120	* @info2off: Offset in bytes to the backup info block of this arena.
	121	* @freelist: Pointer to in-memory list of free blocks
	122	* @rtt: Pointer to in-memory "Read Tracking Table"
	123	* @map_locks: Spinlocks protecting concurrent map writes
	124	* @nd_btt: Pointer to parent nd_btt structure.
	125	* @list: List head for list of arenas
	126	* @debugfs_dir: Debugfs dentry
	127	* @flags: Arena flags - may signify error states.
	128	*
	129	* arena_info is a per-arena handle. Once an arena is narrowed down for an
	130	* IO, this struct is passed around for the duration of the IO.
	131	*/
	132	struct arena_info {
	133	u64 size; /* Total bytes for this arena */
	134	u64 external_lba_start;
	135	u32 internal_nlba;
	136	u32 internal_lbasize;
	137	u32 external_nlba;
	138	u32 external_lbasize;
	139	u32 nfree;
	140	u16 version_major;
	141	u16 version_minor;
adfc036d	142	u32 sector_size;
5212e11f VV	143	/* Byte offsets to the different on-media structures */
	144	u64 nextoff;
	145	u64 infooff;
	146	u64 dataoff;
	147	u64 mapoff;
	148	u64 logoff;
	149	u64 info2off;
	150	/* Pointers to other in-memory structures for this arena */
	151	struct free_entry *freelist;
	152	u32 *rtt;
	153	struct aligned_lock *map_locks;
	154	struct nd_btt *nd_btt;
	155	struct list_head list;
	156	struct dentry *debugfs_dir;
	157	/* Arena flags */
	158	u32 flags;
ebaccf71	159	struct mutex err_lock;
5212e11f VV	160	};
	161
	162	/**
	163	* struct btt - handle for a BTT instance
	164	* @btt_disk: Pointer to the gendisk for BTT device
	165	* @btt_queue: Pointer to the request queue for the BTT device
	166	* @arena_list: Head of the list of arenas
	167	* @debugfs_dir: Debugfs dentry
	168	* @nd_btt: Parent nd_btt struct
	169	* @nlba: Number of logical blocks exposed to the upper layers
	170	* after removing the amount of space needed by metadata
	171	* @rawsize: Total size in bytes of the available backing device
	172	* @lbasize: LBA size as requested and presented to upper layers.
	173	* This is sector_size + size of any metadata.
	174	* @sector_size: The Linux sector size - 512 or 4096
	175	* @lanes: Per-lane spinlocks
	176	* @init_lock: Mutex used for the BTT initialization
	177	* @init_state: Flag describing the initialization state for the BTT
	178	* @num_arenas: Number of arenas in the BTT instance
	179	*/
	180	struct btt {
	181	struct gendisk *btt_disk;
	182	struct request_queue *btt_queue;
	183	struct list_head arena_list;
	184	struct dentry *debugfs_dir;
	185	struct nd_btt *nd_btt;
	186	u64 nlba;
	187	unsigned long long rawsize;
	188	u32 lbasize;
	189	u32 sector_size;
	190	struct nd_region *nd_region;
	191	struct mutex init_lock;
	192	int init_state;
	193	int num_arenas;
ebaccf71	194	struct badblocks *phys_bb;
5212e11f	195	};
ab45e763 VV	196
ab45e763 VV	197	bool nd_btt_arena_is_valid(struct nd_btt nd_btt, struct btt_sb super);
14e49454 VV	198	int nd_btt_version(struct nd_btt nd_btt, struct nd_namespace_common ndns,
14e49454 VV	199	struct btt_sb *btt_sb);
ab45e763	200
8c2f7e86	201	#endif