v4.19.13 snapshot.
diff --git a/drivers/lightnvm/pblk.h b/drivers/lightnvm/pblk.h
new file mode 100644
index 0000000..4760af7
--- /dev/null
+++ b/drivers/lightnvm/pblk.h
@@ -0,0 +1,1444 @@
+/*
+ * Copyright (C) 2015 IT University of Copenhagen (rrpc.h)
+ * Copyright (C) 2016 CNEX Labs
+ * Initial release: Matias Bjorling <matias@cnexlabs.com>
+ * Write buffering: Javier Gonzalez <javier@cnexlabs.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * Implementation of a Physical Block-device target for Open-channel SSDs.
+ *
+ */
+
+#ifndef PBLK_H_
+#define PBLK_H_
+
+#include <linux/blkdev.h>
+#include <linux/blk-mq.h>
+#include <linux/bio.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/vmalloc.h>
+#include <linux/crc32.h>
+#include <linux/uuid.h>
+
+#include <linux/lightnvm.h>
+
+/* Run only GC if less than 1/X blocks are free */
+#define GC_LIMIT_INVERSE 5
+#define GC_TIME_MSECS 1000
+
+#define PBLK_SECTOR (512)
+#define PBLK_EXPOSED_PAGE_SIZE (4096)
+#define PBLK_MAX_REQ_ADDRS (64)
+#define PBLK_MAX_REQ_ADDRS_PW (6)
+
+#define PBLK_NR_CLOSE_JOBS (4)
+
+#define PBLK_CACHE_NAME_LEN (DISK_NAME_LEN + 16)
+
+#define PBLK_COMMAND_TIMEOUT_MS 30000
+
+/* Max 512 LUNs per device */
+#define PBLK_MAX_LUNS_BITMAP (4)
+
+#define NR_PHY_IN_LOG (PBLK_EXPOSED_PAGE_SIZE / PBLK_SECTOR)
+
+/* Static pool sizes */
+#define PBLK_GEN_WS_POOL_SIZE (2)
+
+#define PBLK_DEFAULT_OP (11)
+
+enum {
+	PBLK_READ		= READ,
+	PBLK_WRITE		= WRITE,/* Write from write buffer */
+	PBLK_WRITE_INT,			/* Internal write - no write buffer */
+	PBLK_READ_RECOV,		/* Recovery read - errors allowed */
+	PBLK_ERASE,
+};
+
+enum {
+	/* IO Types */
+	PBLK_IOTYPE_USER	= 1 << 0,
+	PBLK_IOTYPE_GC		= 1 << 1,
+
+	/* Write buffer flags */
+	PBLK_FLUSH_ENTRY	= 1 << 2,
+	PBLK_WRITTEN_DATA	= 1 << 3,
+	PBLK_SUBMITTED_ENTRY	= 1 << 4,
+	PBLK_WRITABLE_ENTRY	= 1 << 5,
+};
+
+enum {
+	PBLK_BLK_ST_OPEN =	0x1,
+	PBLK_BLK_ST_CLOSED =	0x2,
+};
+
+struct pblk_sec_meta {
+	u64 reserved;
+	__le64 lba;
+};
+
+/* The number of GC lists and the rate-limiter states go together. This way the
+ * rate-limiter can dictate how much GC is needed based on resource utilization.
+ */
+#define PBLK_GC_NR_LISTS 4
+
+enum {
+	PBLK_RL_OFF = 0,
+	PBLK_RL_WERR = 1,
+	PBLK_RL_HIGH = 2,
+	PBLK_RL_MID = 3,
+	PBLK_RL_LOW = 4
+};
+
+#define pblk_dma_meta_size (sizeof(struct pblk_sec_meta) * PBLK_MAX_REQ_ADDRS)
+#define pblk_dma_ppa_size (sizeof(u64) * PBLK_MAX_REQ_ADDRS)
+
+/* write buffer completion context */
+struct pblk_c_ctx {
+	struct list_head list;		/* Head for out-of-order completion */
+
+	unsigned long *lun_bitmap;	/* Luns used on current request */
+	unsigned int sentry;
+	unsigned int nr_valid;
+	unsigned int nr_padded;
+};
+
+/* read context */
+struct pblk_g_ctx {
+	void *private;
+	unsigned long start_time;
+	u64 lba;
+};
+
+/* partial read context */
+struct pblk_pr_ctx {
+	struct bio *orig_bio;
+	DECLARE_BITMAP(bitmap, NVM_MAX_VLBA);
+	unsigned int orig_nr_secs;
+	unsigned int bio_init_idx;
+	void *ppa_ptr;
+	dma_addr_t dma_ppa_list;
+};
+
+/* Pad context */
+struct pblk_pad_rq {
+	struct pblk *pblk;
+	struct completion wait;
+	struct kref ref;
+};
+
+/* Recovery context */
+struct pblk_rec_ctx {
+	struct pblk *pblk;
+	struct nvm_rq *rqd;
+	struct work_struct ws_rec;
+};
+
+/* Write context */
+struct pblk_w_ctx {
+	struct bio_list bios;		/* Original bios - used for completion
+					 * in REQ_FUA, REQ_FLUSH case
+					 */
+	u64 lba;			/* Logic addr. associated with entry */
+	struct ppa_addr ppa;		/* Physic addr. associated with entry */
+	int flags;			/* Write context flags */
+};
+
+struct pblk_rb_entry {
+	struct ppa_addr cacheline;	/* Cacheline for this entry */
+	void *data;			/* Pointer to data on this entry */
+	struct pblk_w_ctx w_ctx;	/* Context for this entry */
+	struct list_head index;		/* List head to enable indexes */
+};
+
+#define EMPTY_ENTRY (~0U)
+
+struct pblk_rb_pages {
+	struct page *pages;
+	int order;
+	struct list_head list;
+};
+
+struct pblk_rb {
+	struct pblk_rb_entry *entries;	/* Ring buffer entries */
+	unsigned int mem;		/* Write offset - points to next
+					 * writable entry in memory
+					 */
+	unsigned int subm;		/* Read offset - points to last entry
+					 * that has been submitted to the media
+					 * to be persisted
+					 */
+	unsigned int sync;		/* Synced - backpointer that signals
+					 * the last submitted entry that has
+					 * been successfully persisted to media
+					 */
+	unsigned int flush_point;	/* Sync point - last entry that must be
+					 * flushed to the media. Used with
+					 * REQ_FLUSH and REQ_FUA
+					 */
+	unsigned int l2p_update;	/* l2p update point - next entry for
+					 * which l2p mapping will be updated to
+					 * contain a device ppa address (instead
+					 * of a cacheline
+					 */
+	unsigned int nr_entries;	/* Number of entries in write buffer -
+					 * must be a power of two
+					 */
+	unsigned int seg_size;		/* Size of the data segments being
+					 * stored on each entry. Typically this
+					 * will be 4KB
+					 */
+
+	struct list_head pages;		/* List of data pages */
+
+	spinlock_t w_lock;		/* Write lock */
+	spinlock_t s_lock;		/* Sync lock */
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+	atomic_t inflight_flush_point;	/* Not served REQ_FLUSH | REQ_FUA */
+#endif
+};
+
+#define PBLK_RECOVERY_SECTORS 16
+
+struct pblk_lun {
+	struct ppa_addr bppa;
+	struct semaphore wr_sem;
+};
+
+struct pblk_gc_rq {
+	struct pblk_line *line;
+	void *data;
+	u64 paddr_list[PBLK_MAX_REQ_ADDRS];
+	u64 lba_list[PBLK_MAX_REQ_ADDRS];
+	int nr_secs;
+	int secs_to_gc;
+	struct list_head list;
+};
+
+struct pblk_gc {
+	/* These states are not protected by a lock since (i) they are in the
+	 * fast path, and (ii) they are not critical.
+	 */
+	int gc_active;
+	int gc_enabled;
+	int gc_forced;
+
+	struct task_struct *gc_ts;
+	struct task_struct *gc_writer_ts;
+	struct task_struct *gc_reader_ts;
+
+	struct workqueue_struct *gc_line_reader_wq;
+	struct workqueue_struct *gc_reader_wq;
+
+	struct timer_list gc_timer;
+
+	struct semaphore gc_sem;
+	atomic_t read_inflight_gc; /* Number of lines with inflight GC reads */
+	atomic_t pipeline_gc;	   /* Number of lines in the GC pipeline -
+				    * started reads to finished writes
+				    */
+	int w_entries;
+
+	struct list_head w_list;
+	struct list_head r_list;
+
+	spinlock_t lock;
+	spinlock_t w_lock;
+	spinlock_t r_lock;
+};
+
+struct pblk_rl {
+	unsigned int high;	/* Upper threshold for rate limiter (free run -
+				 * user I/O rate limiter
+				 */
+	unsigned int high_pw;	/* High rounded up as a power of 2 */
+
+#define PBLK_USER_HIGH_THRS 8	/* Begin write limit at 12% available blks */
+#define PBLK_USER_LOW_THRS 10	/* Aggressive GC at 10% available blocks */
+
+	int rb_windows_pw;	/* Number of rate windows in the write buffer
+				 * given as a power-of-2. This guarantees that
+				 * when user I/O is being rate limited, there
+				 * will be reserved enough space for the GC to
+				 * place its payload. A window is of
+				 * pblk->max_write_pgs size, which in NVMe is
+				 * 64, i.e., 256kb.
+				 */
+	int rb_budget;		/* Total number of entries available for I/O */
+	int rb_user_max;	/* Max buffer entries available for user I/O */
+	int rb_gc_max;		/* Max buffer entries available for GC I/O */
+	int rb_gc_rsv;		/* Reserved buffer entries for GC I/O */
+	int rb_state;		/* Rate-limiter current state */
+	int rb_max_io;		/* Maximum size for an I/O giving the config */
+
+	atomic_t rb_user_cnt;	/* User I/O buffer counter */
+	atomic_t rb_gc_cnt;	/* GC I/O buffer counter */
+	atomic_t rb_space;	/* Space limit in case of reaching capacity */
+
+	int rsv_blocks;		/* Reserved blocks for GC */
+
+	int rb_user_active;
+	int rb_gc_active;
+
+	atomic_t werr_lines;	/* Number of write error lines that needs gc */
+
+	struct timer_list u_timer;
+
+	unsigned long long nr_secs;
+	unsigned long total_blocks;
+
+	atomic_t free_blocks;		/* Total number of free blocks (+ OP) */
+	atomic_t free_user_blocks;	/* Number of user free blocks (no OP) */
+};
+
+#define PBLK_LINE_EMPTY (~0U)
+
+enum {
+	/* Line Types */
+	PBLK_LINETYPE_FREE = 0,
+	PBLK_LINETYPE_LOG = 1,
+	PBLK_LINETYPE_DATA = 2,
+
+	/* Line state */
+	PBLK_LINESTATE_NEW = 9,
+	PBLK_LINESTATE_FREE = 10,
+	PBLK_LINESTATE_OPEN = 11,
+	PBLK_LINESTATE_CLOSED = 12,
+	PBLK_LINESTATE_GC = 13,
+	PBLK_LINESTATE_BAD = 14,
+	PBLK_LINESTATE_CORRUPT = 15,
+
+	/* GC group */
+	PBLK_LINEGC_NONE = 20,
+	PBLK_LINEGC_EMPTY = 21,
+	PBLK_LINEGC_LOW = 22,
+	PBLK_LINEGC_MID = 23,
+	PBLK_LINEGC_HIGH = 24,
+	PBLK_LINEGC_FULL = 25,
+	PBLK_LINEGC_WERR = 26
+};
+
+#define PBLK_MAGIC 0x70626c6b /*pblk*/
+
+/* emeta/smeta persistent storage format versions:
+ * Changes in major version requires offline migration.
+ * Changes in minor version are handled automatically during
+ * recovery.
+ */
+
+#define SMETA_VERSION_MAJOR (0)
+#define SMETA_VERSION_MINOR (1)
+
+#define EMETA_VERSION_MAJOR (0)
+#define EMETA_VERSION_MINOR (2)
+
+struct line_header {
+	__le32 crc;
+	__le32 identifier;	/* pblk identifier */
+	__u8 uuid[16];		/* instance uuid */
+	__le16 type;		/* line type */
+	__u8 version_major;	/* version major */
+	__u8 version_minor;	/* version minor */
+	__le32 id;		/* line id for current line */
+};
+
+struct line_smeta {
+	struct line_header header;
+
+	__le32 crc;		/* Full structure including struct crc */
+	/* Previous line metadata */
+	__le32 prev_id;		/* Line id for previous line */
+
+	/* Current line metadata */
+	__le64 seq_nr;		/* Sequence number for current line */
+
+	/* Active writers */
+	__le32 window_wr_lun;	/* Number of parallel LUNs to write */
+
+	__le32 rsvd[2];
+
+	__le64 lun_bitmap[];
+};
+
+
+/*
+ * Metadata layout in media:
+ *	First sector:
+ *		1. struct line_emeta
+ *		2. bad block bitmap (u64 * window_wr_lun)
+ *		3. write amplification counters
+ *	Mid sectors (start at lbas_sector):
+ *		3. nr_lbas (u64) forming lba list
+ *	Last sectors (start at vsc_sector):
+ *		4. u32 valid sector count (vsc) for all lines (~0U: free line)
+ */
+struct line_emeta {
+	struct line_header header;
+
+	__le32 crc;		/* Full structure including struct crc */
+
+	/* Previous line metadata */
+	__le32 prev_id;		/* Line id for prev line */
+
+	/* Current line metadata */
+	__le64 seq_nr;		/* Sequence number for current line */
+
+	/* Active writers */
+	__le32 window_wr_lun;	/* Number of parallel LUNs to write */
+
+	/* Bookkeeping for recovery */
+	__le32 next_id;		/* Line id for next line */
+	__le64 nr_lbas;		/* Number of lbas mapped in line */
+	__le64 nr_valid_lbas;	/* Number of valid lbas mapped in line */
+	__le64 bb_bitmap[];     /* Updated bad block bitmap for line */
+};
+
+
+/* Write amplification counters stored on media */
+struct wa_counters {
+	__le64 user;		/* Number of user written sectors */
+	__le64 gc;		/* Number of sectors written by GC*/
+	__le64 pad;		/* Number of padded sectors */
+};
+
+struct pblk_emeta {
+	struct line_emeta *buf;		/* emeta buffer in media format */
+	int mem;			/* Write offset - points to next
+					 * writable entry in memory
+					 */
+	atomic_t sync;			/* Synced - backpointer that signals the
+					 * last entry that has been successfully
+					 * persisted to media
+					 */
+	unsigned int nr_entries;	/* Number of emeta entries */
+};
+
+struct pblk_smeta {
+	struct line_smeta *buf;		/* smeta buffer in persistent format */
+};
+
+struct pblk_w_err_gc {
+	int has_write_err;
+	__le64 *lba_list;
+};
+
+struct pblk_line {
+	struct pblk *pblk;
+	unsigned int id;		/* Line number corresponds to the
+					 * block line
+					 */
+	unsigned int seq_nr;		/* Unique line sequence number */
+
+	int state;			/* PBLK_LINESTATE_X */
+	int type;			/* PBLK_LINETYPE_X */
+	int gc_group;			/* PBLK_LINEGC_X */
+	struct list_head list;		/* Free, GC lists */
+
+	unsigned long *lun_bitmap;	/* Bitmap for LUNs mapped in line */
+
+	struct nvm_chk_meta *chks;	/* Chunks forming line */
+
+	struct pblk_smeta *smeta;	/* Start metadata */
+	struct pblk_emeta *emeta;	/* End medatada */
+
+	int meta_line;			/* Metadata line id */
+	int meta_distance;		/* Distance between data and metadata */
+
+	u64 smeta_ssec;			/* Sector where smeta starts */
+	u64 emeta_ssec;			/* Sector where emeta starts */
+
+	unsigned int sec_in_line;	/* Number of usable secs in line */
+
+	atomic_t blk_in_line;		/* Number of good blocks in line */
+	unsigned long *blk_bitmap;	/* Bitmap for valid/invalid blocks */
+	unsigned long *erase_bitmap;	/* Bitmap for erased blocks */
+
+	unsigned long *map_bitmap;	/* Bitmap for mapped sectors in line */
+	unsigned long *invalid_bitmap;	/* Bitmap for invalid sectors in line */
+
+	atomic_t left_eblks;		/* Blocks left for erasing */
+	atomic_t left_seblks;		/* Blocks left for sync erasing */
+
+	int left_msecs;			/* Sectors left for mapping */
+	unsigned int cur_sec;		/* Sector map pointer */
+	unsigned int nr_valid_lbas;	/* Number of valid lbas in line */
+
+	__le32 *vsc;			/* Valid sector count in line */
+
+	struct kref ref;		/* Write buffer L2P references */
+
+	struct pblk_w_err_gc *w_err_gc;	/* Write error gc recovery metadata */
+
+	spinlock_t lock;		/* Necessary for invalid_bitmap only */
+};
+
+#define PBLK_DATA_LINES 4
+
+enum {
+	PBLK_KMALLOC_META = 1,
+	PBLK_VMALLOC_META = 2,
+};
+
+enum {
+	PBLK_EMETA_TYPE_HEADER = 1,	/* struct line_emeta first sector */
+	PBLK_EMETA_TYPE_LLBA = 2,	/* lba list - type: __le64 */
+	PBLK_EMETA_TYPE_VSC = 3,	/* vsc list - type: __le32 */
+};
+
+struct pblk_line_mgmt {
+	int nr_lines;			/* Total number of full lines */
+	int nr_free_lines;		/* Number of full lines in free list */
+
+	/* Free lists - use free_lock */
+	struct list_head free_list;	/* Full lines ready to use */
+	struct list_head corrupt_list;	/* Full lines corrupted */
+	struct list_head bad_list;	/* Full lines bad */
+
+	/* GC lists - use gc_lock */
+	struct list_head *gc_lists[PBLK_GC_NR_LISTS];
+	struct list_head gc_high_list;	/* Full lines ready to GC, high isc */
+	struct list_head gc_mid_list;	/* Full lines ready to GC, mid isc */
+	struct list_head gc_low_list;	/* Full lines ready to GC, low isc */
+
+	struct list_head gc_werr_list;  /* Write err recovery list */
+
+	struct list_head gc_full_list;	/* Full lines ready to GC, no valid */
+	struct list_head gc_empty_list;	/* Full lines close, all valid */
+
+	struct pblk_line *log_line;	/* Current FTL log line */
+	struct pblk_line *data_line;	/* Current data line */
+	struct pblk_line *log_next;	/* Next FTL log line */
+	struct pblk_line *data_next;	/* Next data line */
+
+	struct list_head emeta_list;	/* Lines queued to schedule emeta */
+
+	__le32 *vsc_list;		/* Valid sector counts for all lines */
+
+	/* Metadata allocation type: VMALLOC | KMALLOC */
+	int emeta_alloc_type;
+
+	/* Pre-allocated metadata for data lines */
+	struct pblk_smeta *sline_meta[PBLK_DATA_LINES];
+	struct pblk_emeta *eline_meta[PBLK_DATA_LINES];
+	unsigned long meta_bitmap;
+
+	/* Helpers for fast bitmap calculations */
+	unsigned long *bb_template;
+	unsigned long *bb_aux;
+
+	unsigned long d_seq_nr;		/* Data line unique sequence number */
+	unsigned long l_seq_nr;		/* Log line unique sequence number */
+
+	spinlock_t free_lock;
+	spinlock_t close_lock;
+	spinlock_t gc_lock;
+};
+
+struct pblk_line_meta {
+	unsigned int smeta_len;		/* Total length for smeta */
+	unsigned int smeta_sec;		/* Sectors needed for smeta */
+
+	unsigned int emeta_len[4];	/* Lengths for emeta:
+					 *  [0]: Total
+					 *  [1]: struct line_emeta +
+					 *       bb_bitmap + struct wa_counters
+					 *  [2]: L2P portion
+					 *  [3]: vsc
+					 */
+	unsigned int emeta_sec[4];	/* Sectors needed for emeta. Same layout
+					 * as emeta_len
+					 */
+
+	unsigned int emeta_bb;		/* Boundary for bb that affects emeta */
+
+	unsigned int vsc_list_len;	/* Length for vsc list */
+	unsigned int sec_bitmap_len;	/* Length for sector bitmap in line */
+	unsigned int blk_bitmap_len;	/* Length for block bitmap in line */
+	unsigned int lun_bitmap_len;	/* Length for lun bitmap in line */
+
+	unsigned int blk_per_line;	/* Number of blocks in a full line */
+	unsigned int sec_per_line;	/* Number of sectors in a line */
+	unsigned int dsec_per_line;	/* Number of data sectors in a line */
+	unsigned int min_blk_line;	/* Min. number of good blocks in line */
+
+	unsigned int mid_thrs;		/* Threshold for GC mid list */
+	unsigned int high_thrs;		/* Threshold for GC high list */
+
+	unsigned int meta_distance;	/* Distance between data and metadata */
+};
+
+enum {
+	PBLK_STATE_RUNNING = 0,
+	PBLK_STATE_STOPPING = 1,
+	PBLK_STATE_RECOVERING = 2,
+	PBLK_STATE_STOPPED = 3,
+};
+
+/* Internal format to support not power-of-2 device formats */
+struct pblk_addrf {
+	/* gen to dev */
+	int sec_stripe;
+	int ch_stripe;
+	int lun_stripe;
+
+	/* dev to gen */
+	int sec_lun_stripe;
+	int sec_ws_stripe;
+};
+
+struct pblk {
+	struct nvm_tgt_dev *dev;
+	struct gendisk *disk;
+
+	struct kobject kobj;
+
+	struct pblk_lun *luns;
+
+	struct pblk_line *lines;		/* Line array */
+	struct pblk_line_mgmt l_mg;		/* Line management */
+	struct pblk_line_meta lm;		/* Line metadata */
+
+	struct nvm_addrf addrf;		/* Aligned address format */
+	struct pblk_addrf uaddrf;	/* Unaligned address format */
+	int addrf_len;
+
+	struct pblk_rb rwb;
+
+	int state;			/* pblk line state */
+
+	int min_write_pgs; /* Minimum amount of pages required by controller */
+	int max_write_pgs; /* Maximum amount of pages supported by controller */
+
+	sector_t capacity; /* Device capacity when bad blocks are subtracted */
+
+	int op;      /* Percentage of device used for over-provisioning */
+	int op_blks; /* Number of blocks used for over-provisioning */
+
+	/* pblk provisioning values. Used by rate limiter */
+	struct pblk_rl rl;
+
+	int sec_per_write;
+
+	unsigned char instance_uuid[16];
+
+	/* Persistent write amplification counters, 4kb sector I/Os */
+	atomic64_t user_wa;		/* Sectors written by user */
+	atomic64_t gc_wa;		/* Sectors written by GC */
+	atomic64_t pad_wa;		/* Padded sectors written */
+
+	/* Reset values for delta write amplification measurements */
+	u64 user_rst_wa;
+	u64 gc_rst_wa;
+	u64 pad_rst_wa;
+
+	/* Counters used for calculating padding distribution */
+	atomic64_t *pad_dist;		/* Padding distribution buckets */
+	u64 nr_flush_rst;		/* Flushes reset value for pad dist.*/
+	atomic64_t nr_flush;		/* Number of flush/fua I/O */
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+	/* Non-persistent debug counters, 4kb sector I/Os */
+	atomic_long_t inflight_writes;	/* Inflight writes (user and gc) */
+	atomic_long_t padded_writes;	/* Sectors padded due to flush/fua */
+	atomic_long_t padded_wb;	/* Sectors padded in write buffer */
+	atomic_long_t req_writes;	/* Sectors stored on write buffer */
+	atomic_long_t sub_writes;	/* Sectors submitted from buffer */
+	atomic_long_t sync_writes;	/* Sectors synced to media */
+	atomic_long_t inflight_reads;	/* Inflight sector read requests */
+	atomic_long_t cache_reads;	/* Read requests that hit the cache */
+	atomic_long_t sync_reads;	/* Completed sector read requests */
+	atomic_long_t recov_writes;	/* Sectors submitted from recovery */
+	atomic_long_t recov_gc_writes;	/* Sectors submitted from write GC */
+	atomic_long_t recov_gc_reads;	/* Sectors submitted from read GC */
+#endif
+
+	spinlock_t lock;
+
+	atomic_long_t read_failed;
+	atomic_long_t read_empty;
+	atomic_long_t read_high_ecc;
+	atomic_long_t read_failed_gc;
+	atomic_long_t write_failed;
+	atomic_long_t erase_failed;
+
+	atomic_t inflight_io;		/* General inflight I/O counter */
+
+	struct task_struct *writer_ts;
+
+	/* Simple translation map of logical addresses to physical addresses.
+	 * The logical addresses is known by the host system, while the physical
+	 * addresses are used when writing to the disk block device.
+	 */
+	unsigned char *trans_map;
+	spinlock_t trans_lock;
+
+	struct list_head compl_list;
+
+	spinlock_t resubmit_lock;	 /* Resubmit list lock */
+	struct list_head resubmit_list; /* Resubmit list for failed writes*/
+
+	mempool_t page_bio_pool;
+	mempool_t gen_ws_pool;
+	mempool_t rec_pool;
+	mempool_t r_rq_pool;
+	mempool_t w_rq_pool;
+	mempool_t e_rq_pool;
+
+	struct workqueue_struct *close_wq;
+	struct workqueue_struct *bb_wq;
+	struct workqueue_struct *r_end_wq;
+
+	struct timer_list wtimer;
+
+	struct pblk_gc gc;
+};
+
+struct pblk_line_ws {
+	struct pblk *pblk;
+	struct pblk_line *line;
+	void *priv;
+	struct work_struct ws;
+};
+
+#define pblk_g_rq_size (sizeof(struct nvm_rq) + sizeof(struct pblk_g_ctx))
+#define pblk_w_rq_size (sizeof(struct nvm_rq) + sizeof(struct pblk_c_ctx))
+
+#define pblk_err(pblk, fmt, ...)			\
+	pr_err("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
+#define pblk_info(pblk, fmt, ...)			\
+	pr_info("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
+#define pblk_warn(pblk, fmt, ...)			\
+	pr_warn("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
+#define pblk_debug(pblk, fmt, ...)			\
+	pr_debug("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
+
+/*
+ * pblk ring buffer operations
+ */
+int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base,
+		 unsigned int power_size, unsigned int power_seg_sz);
+unsigned int pblk_rb_calculate_size(unsigned int nr_entries);
+void *pblk_rb_entries_ref(struct pblk_rb *rb);
+int pblk_rb_may_write_user(struct pblk_rb *rb, struct bio *bio,
+			   unsigned int nr_entries, unsigned int *pos);
+int pblk_rb_may_write_gc(struct pblk_rb *rb, unsigned int nr_entries,
+			 unsigned int *pos);
+void pblk_rb_write_entry_user(struct pblk_rb *rb, void *data,
+			      struct pblk_w_ctx w_ctx, unsigned int pos);
+void pblk_rb_write_entry_gc(struct pblk_rb *rb, void *data,
+			    struct pblk_w_ctx w_ctx, struct pblk_line *line,
+			    u64 paddr, unsigned int pos);
+struct pblk_w_ctx *pblk_rb_w_ctx(struct pblk_rb *rb, unsigned int pos);
+void pblk_rb_flush(struct pblk_rb *rb);
+
+void pblk_rb_sync_l2p(struct pblk_rb *rb);
+unsigned int pblk_rb_read_to_bio(struct pblk_rb *rb, struct nvm_rq *rqd,
+				 unsigned int pos, unsigned int nr_entries,
+				 unsigned int count);
+int pblk_rb_copy_to_bio(struct pblk_rb *rb, struct bio *bio, sector_t lba,
+			struct ppa_addr ppa, int bio_iter, bool advanced_bio);
+unsigned int pblk_rb_read_commit(struct pblk_rb *rb, unsigned int entries);
+
+unsigned int pblk_rb_sync_init(struct pblk_rb *rb, unsigned long *flags);
+unsigned int pblk_rb_sync_advance(struct pblk_rb *rb, unsigned int nr_entries);
+struct pblk_rb_entry *pblk_rb_sync_scan_entry(struct pblk_rb *rb,
+					      struct ppa_addr *ppa);
+void pblk_rb_sync_end(struct pblk_rb *rb, unsigned long *flags);
+unsigned int pblk_rb_flush_point_count(struct pblk_rb *rb);
+
+unsigned int pblk_rb_read_count(struct pblk_rb *rb);
+unsigned int pblk_rb_sync_count(struct pblk_rb *rb);
+unsigned int pblk_rb_wrap_pos(struct pblk_rb *rb, unsigned int pos);
+
+int pblk_rb_tear_down_check(struct pblk_rb *rb);
+int pblk_rb_pos_oob(struct pblk_rb *rb, u64 pos);
+void pblk_rb_data_free(struct pblk_rb *rb);
+ssize_t pblk_rb_sysfs(struct pblk_rb *rb, char *buf);
+
+/*
+ * pblk core
+ */
+struct nvm_rq *pblk_alloc_rqd(struct pblk *pblk, int type);
+void pblk_free_rqd(struct pblk *pblk, struct nvm_rq *rqd, int type);
+void pblk_set_sec_per_write(struct pblk *pblk, int sec_per_write);
+int pblk_setup_w_rec_rq(struct pblk *pblk, struct nvm_rq *rqd,
+			struct pblk_c_ctx *c_ctx);
+void pblk_discard(struct pblk *pblk, struct bio *bio);
+struct nvm_chk_meta *pblk_chunk_get_info(struct pblk *pblk);
+struct nvm_chk_meta *pblk_chunk_get_off(struct pblk *pblk,
+					      struct nvm_chk_meta *lp,
+					      struct ppa_addr ppa);
+void pblk_log_write_err(struct pblk *pblk, struct nvm_rq *rqd);
+void pblk_log_read_err(struct pblk *pblk, struct nvm_rq *rqd);
+int pblk_submit_io(struct pblk *pblk, struct nvm_rq *rqd);
+int pblk_submit_io_sync(struct pblk *pblk, struct nvm_rq *rqd);
+int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line);
+struct bio *pblk_bio_map_addr(struct pblk *pblk, void *data,
+			      unsigned int nr_secs, unsigned int len,
+			      int alloc_type, gfp_t gfp_mask);
+struct pblk_line *pblk_line_get(struct pblk *pblk);
+struct pblk_line *pblk_line_get_first_data(struct pblk *pblk);
+struct pblk_line *pblk_line_replace_data(struct pblk *pblk);
+int pblk_line_recov_alloc(struct pblk *pblk, struct pblk_line *line);
+void pblk_line_recov_close(struct pblk *pblk, struct pblk_line *line);
+struct pblk_line *pblk_line_get_data(struct pblk *pblk);
+struct pblk_line *pblk_line_get_erase(struct pblk *pblk);
+int pblk_line_erase(struct pblk *pblk, struct pblk_line *line);
+int pblk_line_is_full(struct pblk_line *line);
+void pblk_line_free(struct pblk_line *line);
+void pblk_line_close_meta(struct pblk *pblk, struct pblk_line *line);
+void pblk_line_close(struct pblk *pblk, struct pblk_line *line);
+void pblk_line_close_ws(struct work_struct *work);
+void pblk_pipeline_stop(struct pblk *pblk);
+void __pblk_pipeline_stop(struct pblk *pblk);
+void __pblk_pipeline_flush(struct pblk *pblk);
+void pblk_gen_run_ws(struct pblk *pblk, struct pblk_line *line, void *priv,
+		     void (*work)(struct work_struct *), gfp_t gfp_mask,
+		     struct workqueue_struct *wq);
+u64 pblk_line_smeta_start(struct pblk *pblk, struct pblk_line *line);
+int pblk_line_read_smeta(struct pblk *pblk, struct pblk_line *line);
+int pblk_line_read_emeta(struct pblk *pblk, struct pblk_line *line,
+			 void *emeta_buf);
+int pblk_blk_erase_async(struct pblk *pblk, struct ppa_addr erase_ppa);
+void pblk_line_put(struct kref *ref);
+void pblk_line_put_wq(struct kref *ref);
+struct list_head *pblk_line_gc_list(struct pblk *pblk, struct pblk_line *line);
+u64 pblk_lookup_page(struct pblk *pblk, struct pblk_line *line);
+void pblk_dealloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs);
+u64 pblk_alloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs);
+u64 __pblk_alloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs);
+int pblk_calc_secs(struct pblk *pblk, unsigned long secs_avail,
+		   unsigned long secs_to_flush);
+void pblk_up_page(struct pblk *pblk, struct ppa_addr *ppa_list, int nr_ppas);
+void pblk_down_rq(struct pblk *pblk, struct ppa_addr *ppa_list, int nr_ppas,
+		  unsigned long *lun_bitmap);
+void pblk_down_page(struct pblk *pblk, struct ppa_addr *ppa_list, int nr_ppas);
+void pblk_up_rq(struct pblk *pblk, struct ppa_addr *ppa_list, int nr_ppas,
+		unsigned long *lun_bitmap);
+int pblk_bio_add_pages(struct pblk *pblk, struct bio *bio, gfp_t flags,
+		       int nr_pages);
+void pblk_bio_free_pages(struct pblk *pblk, struct bio *bio, int off,
+			 int nr_pages);
+void pblk_map_invalidate(struct pblk *pblk, struct ppa_addr ppa);
+void __pblk_map_invalidate(struct pblk *pblk, struct pblk_line *line,
+			   u64 paddr);
+void pblk_update_map(struct pblk *pblk, sector_t lba, struct ppa_addr ppa);
+void pblk_update_map_cache(struct pblk *pblk, sector_t lba,
+			   struct ppa_addr ppa);
+void pblk_update_map_dev(struct pblk *pblk, sector_t lba,
+			 struct ppa_addr ppa, struct ppa_addr entry_line);
+int pblk_update_map_gc(struct pblk *pblk, sector_t lba, struct ppa_addr ppa,
+		       struct pblk_line *gc_line, u64 paddr);
+void pblk_lookup_l2p_rand(struct pblk *pblk, struct ppa_addr *ppas,
+			  u64 *lba_list, int nr_secs);
+void pblk_lookup_l2p_seq(struct pblk *pblk, struct ppa_addr *ppas,
+			 sector_t blba, int nr_secs);
+
+/*
+ * pblk user I/O write path
+ */
+int pblk_write_to_cache(struct pblk *pblk, struct bio *bio,
+			unsigned long flags);
+int pblk_write_gc_to_cache(struct pblk *pblk, struct pblk_gc_rq *gc_rq);
+
+/*
+ * pblk map
+ */
+void pblk_map_erase_rq(struct pblk *pblk, struct nvm_rq *rqd,
+		       unsigned int sentry, unsigned long *lun_bitmap,
+		       unsigned int valid_secs, struct ppa_addr *erase_ppa);
+void pblk_map_rq(struct pblk *pblk, struct nvm_rq *rqd, unsigned int sentry,
+		 unsigned long *lun_bitmap, unsigned int valid_secs,
+		 unsigned int off);
+
+/*
+ * pblk write thread
+ */
+int pblk_write_ts(void *data);
+void pblk_write_timer_fn(struct timer_list *t);
+void pblk_write_should_kick(struct pblk *pblk);
+void pblk_write_kick(struct pblk *pblk);
+
+/*
+ * pblk read path
+ */
+extern struct bio_set pblk_bio_set;
+int pblk_submit_read(struct pblk *pblk, struct bio *bio);
+int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq);
+/*
+ * pblk recovery
+ */
+struct pblk_line *pblk_recov_l2p(struct pblk *pblk);
+int pblk_recov_pad(struct pblk *pblk);
+int pblk_recov_check_emeta(struct pblk *pblk, struct line_emeta *emeta);
+
+/*
+ * pblk gc
+ */
+#define PBLK_GC_MAX_READERS 8	/* Max number of outstanding GC reader jobs */
+#define PBLK_GC_RQ_QD 128	/* Queue depth for inflight GC requests */
+#define PBLK_GC_L_QD 4		/* Queue depth for inflight GC lines */
+#define PBLK_GC_RSV_LINE 1	/* Reserved lines for GC */
+
+int pblk_gc_init(struct pblk *pblk);
+void pblk_gc_exit(struct pblk *pblk, bool graceful);
+void pblk_gc_should_start(struct pblk *pblk);
+void pblk_gc_should_stop(struct pblk *pblk);
+void pblk_gc_should_kick(struct pblk *pblk);
+void pblk_gc_free_full_lines(struct pblk *pblk);
+void pblk_gc_sysfs_state_show(struct pblk *pblk, int *gc_enabled,
+			      int *gc_active);
+int pblk_gc_sysfs_force(struct pblk *pblk, int force);
+
+/*
+ * pblk rate limiter
+ */
+void pblk_rl_init(struct pblk_rl *rl, int budget);
+void pblk_rl_free(struct pblk_rl *rl);
+void pblk_rl_update_rates(struct pblk_rl *rl);
+int pblk_rl_high_thrs(struct pblk_rl *rl);
+unsigned long pblk_rl_nr_free_blks(struct pblk_rl *rl);
+unsigned long pblk_rl_nr_user_free_blks(struct pblk_rl *rl);
+int pblk_rl_user_may_insert(struct pblk_rl *rl, int nr_entries);
+void pblk_rl_inserted(struct pblk_rl *rl, int nr_entries);
+void pblk_rl_user_in(struct pblk_rl *rl, int nr_entries);
+int pblk_rl_gc_may_insert(struct pblk_rl *rl, int nr_entries);
+void pblk_rl_gc_in(struct pblk_rl *rl, int nr_entries);
+void pblk_rl_out(struct pblk_rl *rl, int nr_user, int nr_gc);
+int pblk_rl_max_io(struct pblk_rl *rl);
+void pblk_rl_free_lines_inc(struct pblk_rl *rl, struct pblk_line *line);
+void pblk_rl_free_lines_dec(struct pblk_rl *rl, struct pblk_line *line,
+			    bool used);
+int pblk_rl_is_limit(struct pblk_rl *rl);
+
+void pblk_rl_werr_line_in(struct pblk_rl *rl);
+void pblk_rl_werr_line_out(struct pblk_rl *rl);
+
+/*
+ * pblk sysfs
+ */
+int pblk_sysfs_init(struct gendisk *tdisk);
+void pblk_sysfs_exit(struct gendisk *tdisk);
+
+static inline void *pblk_malloc(size_t size, int type, gfp_t flags)
+{
+	if (type == PBLK_KMALLOC_META)
+		return kmalloc(size, flags);
+	return vmalloc(size);
+}
+
+static inline void pblk_mfree(void *ptr, int type)
+{
+	if (type == PBLK_KMALLOC_META)
+		kfree(ptr);
+	else
+		vfree(ptr);
+}
+
+static inline struct nvm_rq *nvm_rq_from_c_ctx(void *c_ctx)
+{
+	return c_ctx - sizeof(struct nvm_rq);
+}
+
+static inline void *emeta_to_bb(struct line_emeta *emeta)
+{
+	return emeta->bb_bitmap;
+}
+
+static inline void *emeta_to_wa(struct pblk_line_meta *lm,
+				struct line_emeta *emeta)
+{
+	return emeta->bb_bitmap + lm->blk_bitmap_len;
+}
+
+static inline void *emeta_to_lbas(struct pblk *pblk, struct line_emeta *emeta)
+{
+	return ((void *)emeta + pblk->lm.emeta_len[1]);
+}
+
+static inline void *emeta_to_vsc(struct pblk *pblk, struct line_emeta *emeta)
+{
+	return (emeta_to_lbas(pblk, emeta) + pblk->lm.emeta_len[2]);
+}
+
+static inline int pblk_line_vsc(struct pblk_line *line)
+{
+	return le32_to_cpu(*line->vsc);
+}
+
+static inline int pblk_pad_distance(struct pblk *pblk)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+
+	return geo->mw_cunits * geo->all_luns * geo->ws_opt;
+}
+
+static inline int pblk_ppa_to_line(struct ppa_addr p)
+{
+	return p.a.blk;
+}
+
+static inline int pblk_ppa_to_pos(struct nvm_geo *geo, struct ppa_addr p)
+{
+	return p.a.lun * geo->num_ch + p.a.ch;
+}
+
+static inline struct ppa_addr addr_to_gen_ppa(struct pblk *pblk, u64 paddr,
+					      u64 line_id)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	struct ppa_addr ppa;
+
+	if (geo->version == NVM_OCSSD_SPEC_12) {
+		struct nvm_addrf_12 *ppaf = (struct nvm_addrf_12 *)&pblk->addrf;
+
+		ppa.ppa = 0;
+		ppa.g.blk = line_id;
+		ppa.g.pg = (paddr & ppaf->pg_mask) >> ppaf->pg_offset;
+		ppa.g.lun = (paddr & ppaf->lun_mask) >> ppaf->lun_offset;
+		ppa.g.ch = (paddr & ppaf->ch_mask) >> ppaf->ch_offset;
+		ppa.g.pl = (paddr & ppaf->pln_mask) >> ppaf->pln_offset;
+		ppa.g.sec = (paddr & ppaf->sec_mask) >> ppaf->sec_offset;
+	} else {
+		struct pblk_addrf *uaddrf = &pblk->uaddrf;
+		int secs, chnls, luns;
+
+		ppa.ppa = 0;
+
+		ppa.m.chk = line_id;
+
+		paddr = div_u64_rem(paddr, uaddrf->sec_stripe, &secs);
+		ppa.m.sec = secs;
+
+		paddr = div_u64_rem(paddr, uaddrf->ch_stripe, &chnls);
+		ppa.m.grp = chnls;
+
+		paddr = div_u64_rem(paddr, uaddrf->lun_stripe, &luns);
+		ppa.m.pu = luns;
+
+		ppa.m.sec += uaddrf->sec_stripe * paddr;
+	}
+
+	return ppa;
+}
+
+static inline u64 pblk_dev_ppa_to_line_addr(struct pblk *pblk,
+							struct ppa_addr p)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	u64 paddr;
+
+	if (geo->version == NVM_OCSSD_SPEC_12) {
+		struct nvm_addrf_12 *ppaf = (struct nvm_addrf_12 *)&pblk->addrf;
+
+		paddr = (u64)p.g.ch << ppaf->ch_offset;
+		paddr |= (u64)p.g.lun << ppaf->lun_offset;
+		paddr |= (u64)p.g.pg << ppaf->pg_offset;
+		paddr |= (u64)p.g.pl << ppaf->pln_offset;
+		paddr |= (u64)p.g.sec << ppaf->sec_offset;
+	} else {
+		struct pblk_addrf *uaddrf = &pblk->uaddrf;
+		u64 secs = p.m.sec;
+		int sec_stripe;
+
+		paddr = (u64)p.m.grp * uaddrf->sec_stripe;
+		paddr += (u64)p.m.pu * uaddrf->sec_lun_stripe;
+
+		secs = div_u64_rem(secs, uaddrf->sec_stripe, &sec_stripe);
+		paddr += secs * uaddrf->sec_ws_stripe;
+		paddr += sec_stripe;
+	}
+
+	return paddr;
+}
+
+static inline struct ppa_addr pblk_ppa32_to_ppa64(struct pblk *pblk, u32 ppa32)
+{
+	struct ppa_addr ppa64;
+
+	ppa64.ppa = 0;
+
+	if (ppa32 == -1) {
+		ppa64.ppa = ADDR_EMPTY;
+	} else if (ppa32 & (1U << 31)) {
+		ppa64.c.line = ppa32 & ((~0U) >> 1);
+		ppa64.c.is_cached = 1;
+	} else {
+		struct nvm_tgt_dev *dev = pblk->dev;
+		struct nvm_geo *geo = &dev->geo;
+
+		if (geo->version == NVM_OCSSD_SPEC_12) {
+			struct nvm_addrf_12 *ppaf =
+					(struct nvm_addrf_12 *)&pblk->addrf;
+
+			ppa64.g.ch = (ppa32 & ppaf->ch_mask) >>
+							ppaf->ch_offset;
+			ppa64.g.lun = (ppa32 & ppaf->lun_mask) >>
+							ppaf->lun_offset;
+			ppa64.g.blk = (ppa32 & ppaf->blk_mask) >>
+							ppaf->blk_offset;
+			ppa64.g.pg = (ppa32 & ppaf->pg_mask) >>
+							ppaf->pg_offset;
+			ppa64.g.pl = (ppa32 & ppaf->pln_mask) >>
+							ppaf->pln_offset;
+			ppa64.g.sec = (ppa32 & ppaf->sec_mask) >>
+							ppaf->sec_offset;
+		} else {
+			struct nvm_addrf *lbaf = &pblk->addrf;
+
+			ppa64.m.grp = (ppa32 & lbaf->ch_mask) >>
+							lbaf->ch_offset;
+			ppa64.m.pu = (ppa32 & lbaf->lun_mask) >>
+							lbaf->lun_offset;
+			ppa64.m.chk = (ppa32 & lbaf->chk_mask) >>
+							lbaf->chk_offset;
+			ppa64.m.sec = (ppa32 & lbaf->sec_mask) >>
+							lbaf->sec_offset;
+		}
+	}
+
+	return ppa64;
+}
+
+static inline u32 pblk_ppa64_to_ppa32(struct pblk *pblk, struct ppa_addr ppa64)
+{
+	u32 ppa32 = 0;
+
+	if (ppa64.ppa == ADDR_EMPTY) {
+		ppa32 = ~0U;
+	} else if (ppa64.c.is_cached) {
+		ppa32 |= ppa64.c.line;
+		ppa32 |= 1U << 31;
+	} else {
+		struct nvm_tgt_dev *dev = pblk->dev;
+		struct nvm_geo *geo = &dev->geo;
+
+		if (geo->version == NVM_OCSSD_SPEC_12) {
+			struct nvm_addrf_12 *ppaf =
+					(struct nvm_addrf_12 *)&pblk->addrf;
+
+			ppa32 |= ppa64.g.ch << ppaf->ch_offset;
+			ppa32 |= ppa64.g.lun << ppaf->lun_offset;
+			ppa32 |= ppa64.g.blk << ppaf->blk_offset;
+			ppa32 |= ppa64.g.pg << ppaf->pg_offset;
+			ppa32 |= ppa64.g.pl << ppaf->pln_offset;
+			ppa32 |= ppa64.g.sec << ppaf->sec_offset;
+		} else {
+			struct nvm_addrf *lbaf = &pblk->addrf;
+
+			ppa32 |= ppa64.m.grp << lbaf->ch_offset;
+			ppa32 |= ppa64.m.pu << lbaf->lun_offset;
+			ppa32 |= ppa64.m.chk << lbaf->chk_offset;
+			ppa32 |= ppa64.m.sec << lbaf->sec_offset;
+		}
+	}
+
+	return ppa32;
+}
+
+static inline struct ppa_addr pblk_trans_map_get(struct pblk *pblk,
+								sector_t lba)
+{
+	struct ppa_addr ppa;
+
+	if (pblk->addrf_len < 32) {
+		u32 *map = (u32 *)pblk->trans_map;
+
+		ppa = pblk_ppa32_to_ppa64(pblk, map[lba]);
+	} else {
+		struct ppa_addr *map = (struct ppa_addr *)pblk->trans_map;
+
+		ppa = map[lba];
+	}
+
+	return ppa;
+}
+
+static inline void pblk_trans_map_set(struct pblk *pblk, sector_t lba,
+						struct ppa_addr ppa)
+{
+	if (pblk->addrf_len < 32) {
+		u32 *map = (u32 *)pblk->trans_map;
+
+		map[lba] = pblk_ppa64_to_ppa32(pblk, ppa);
+	} else {
+		u64 *map = (u64 *)pblk->trans_map;
+
+		map[lba] = ppa.ppa;
+	}
+}
+
+static inline int pblk_ppa_empty(struct ppa_addr ppa_addr)
+{
+	return (ppa_addr.ppa == ADDR_EMPTY);
+}
+
+static inline void pblk_ppa_set_empty(struct ppa_addr *ppa_addr)
+{
+	ppa_addr->ppa = ADDR_EMPTY;
+}
+
+static inline bool pblk_ppa_comp(struct ppa_addr lppa, struct ppa_addr rppa)
+{
+	return (lppa.ppa == rppa.ppa);
+}
+
+static inline int pblk_addr_in_cache(struct ppa_addr ppa)
+{
+	return (ppa.ppa != ADDR_EMPTY && ppa.c.is_cached);
+}
+
+static inline int pblk_addr_to_cacheline(struct ppa_addr ppa)
+{
+	return ppa.c.line;
+}
+
+static inline struct ppa_addr pblk_cacheline_to_addr(int addr)
+{
+	struct ppa_addr p;
+
+	p.c.line = addr;
+	p.c.is_cached = 1;
+
+	return p;
+}
+
+static inline u32 pblk_calc_meta_header_crc(struct pblk *pblk,
+					    struct line_header *header)
+{
+	u32 crc = ~(u32)0;
+
+	crc = crc32_le(crc, (unsigned char *)header + sizeof(crc),
+				sizeof(struct line_header) - sizeof(crc));
+
+	return crc;
+}
+
+static inline u32 pblk_calc_smeta_crc(struct pblk *pblk,
+				      struct line_smeta *smeta)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	u32 crc = ~(u32)0;
+
+	crc = crc32_le(crc, (unsigned char *)smeta +
+				sizeof(struct line_header) + sizeof(crc),
+				lm->smeta_len -
+				sizeof(struct line_header) - sizeof(crc));
+
+	return crc;
+}
+
+static inline u32 pblk_calc_emeta_crc(struct pblk *pblk,
+				      struct line_emeta *emeta)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+	u32 crc = ~(u32)0;
+
+	crc = crc32_le(crc, (unsigned char *)emeta +
+				sizeof(struct line_header) + sizeof(crc),
+				lm->emeta_len[0] -
+				sizeof(struct line_header) - sizeof(crc));
+
+	return crc;
+}
+
+static inline int pblk_set_progr_mode(struct pblk *pblk, int type)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	int flags;
+
+	if (geo->version == NVM_OCSSD_SPEC_20)
+		return 0;
+
+	flags = geo->pln_mode >> 1;
+
+	if (type == PBLK_WRITE)
+		flags |= NVM_IO_SCRAMBLE_ENABLE;
+
+	return flags;
+}
+
+enum {
+	PBLK_READ_RANDOM	= 0,
+	PBLK_READ_SEQUENTIAL	= 1,
+};
+
+static inline int pblk_set_read_mode(struct pblk *pblk, int type)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct nvm_geo *geo = &dev->geo;
+	int flags;
+
+	if (geo->version == NVM_OCSSD_SPEC_20)
+		return 0;
+
+	flags = NVM_IO_SUSPEND | NVM_IO_SCRAMBLE_ENABLE;
+	if (type == PBLK_READ_SEQUENTIAL)
+		flags |= geo->pln_mode >> 1;
+
+	return flags;
+}
+
+static inline int pblk_io_aligned(struct pblk *pblk, int nr_secs)
+{
+	return !(nr_secs % pblk->min_write_pgs);
+}
+
+#ifdef CONFIG_NVM_PBLK_DEBUG
+static inline void print_ppa(struct pblk *pblk, struct ppa_addr *p,
+			     char *msg, int error)
+{
+	struct nvm_geo *geo = &pblk->dev->geo;
+
+	if (p->c.is_cached) {
+		pblk_err(pblk, "ppa: (%s: %x) cache line: %llu\n",
+				msg, error, (u64)p->c.line);
+	} else if (geo->version == NVM_OCSSD_SPEC_12) {
+		pblk_err(pblk, "ppa: (%s: %x):ch:%d,lun:%d,blk:%d,pg:%d,pl:%d,sec:%d\n",
+			msg, error,
+			p->g.ch, p->g.lun, p->g.blk,
+			p->g.pg, p->g.pl, p->g.sec);
+	} else {
+		pblk_err(pblk, "ppa: (%s: %x):ch:%d,lun:%d,chk:%d,sec:%d\n",
+			msg, error,
+			p->m.grp, p->m.pu, p->m.chk, p->m.sec);
+	}
+}
+
+static inline void pblk_print_failed_rqd(struct pblk *pblk, struct nvm_rq *rqd,
+					 int error)
+{
+	int bit = -1;
+
+	if (rqd->nr_ppas ==  1) {
+		print_ppa(pblk, &rqd->ppa_addr, "rqd", error);
+		return;
+	}
+
+	while ((bit = find_next_bit((void *)&rqd->ppa_status, rqd->nr_ppas,
+						bit + 1)) < rqd->nr_ppas) {
+		print_ppa(pblk, &rqd->ppa_list[bit], "rqd", error);
+	}
+
+	pblk_err(pblk, "error:%d, ppa_status:%llx\n", error, rqd->ppa_status);
+}
+
+static inline int pblk_boundary_ppa_checks(struct nvm_tgt_dev *tgt_dev,
+				       struct ppa_addr *ppas, int nr_ppas)
+{
+	struct nvm_geo *geo = &tgt_dev->geo;
+	struct ppa_addr *ppa;
+	int i;
+
+	for (i = 0; i < nr_ppas; i++) {
+		ppa = &ppas[i];
+
+		if (geo->version == NVM_OCSSD_SPEC_12) {
+			if (!ppa->c.is_cached &&
+					ppa->g.ch < geo->num_ch &&
+					ppa->g.lun < geo->num_lun &&
+					ppa->g.pl < geo->num_pln &&
+					ppa->g.blk < geo->num_chk &&
+					ppa->g.pg < geo->num_pg &&
+					ppa->g.sec < geo->ws_min)
+				continue;
+		} else {
+			if (!ppa->c.is_cached &&
+					ppa->m.grp < geo->num_ch &&
+					ppa->m.pu < geo->num_lun &&
+					ppa->m.chk < geo->num_chk &&
+					ppa->m.sec < geo->clba)
+				continue;
+		}
+
+		print_ppa(tgt_dev->q->queuedata, ppa, "boundary", i);
+
+		return 1;
+	}
+	return 0;
+}
+
+static inline int pblk_check_io(struct pblk *pblk, struct nvm_rq *rqd)
+{
+	struct nvm_tgt_dev *dev = pblk->dev;
+	struct ppa_addr *ppa_list;
+
+	ppa_list = (rqd->nr_ppas > 1) ? rqd->ppa_list : &rqd->ppa_addr;
+
+	if (pblk_boundary_ppa_checks(dev, ppa_list, rqd->nr_ppas)) {
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	if (rqd->opcode == NVM_OP_PWRITE) {
+		struct pblk_line *line;
+		struct ppa_addr ppa;
+		int i;
+
+		for (i = 0; i < rqd->nr_ppas; i++) {
+			ppa = ppa_list[i];
+			line = &pblk->lines[pblk_ppa_to_line(ppa)];
+
+			spin_lock(&line->lock);
+			if (line->state != PBLK_LINESTATE_OPEN) {
+				pblk_err(pblk, "bad ppa: line:%d,state:%d\n",
+							line->id, line->state);
+				WARN_ON(1);
+				spin_unlock(&line->lock);
+				return -EINVAL;
+			}
+			spin_unlock(&line->lock);
+		}
+	}
+
+	return 0;
+}
+#endif
+
+static inline int pblk_boundary_paddr_checks(struct pblk *pblk, u64 paddr)
+{
+	struct pblk_line_meta *lm = &pblk->lm;
+
+	if (paddr > lm->sec_per_line)
+		return 1;
+
+	return 0;
+}
+
+static inline unsigned int pblk_get_bi_idx(struct bio *bio)
+{
+	return bio->bi_iter.bi_idx;
+}
+
+static inline sector_t pblk_get_lba(struct bio *bio)
+{
+	return bio->bi_iter.bi_sector / NR_PHY_IN_LOG;
+}
+
+static inline unsigned int pblk_get_secs(struct bio *bio)
+{
+	return  bio->bi_iter.bi_size / PBLK_EXPOSED_PAGE_SIZE;
+}
+
+static inline void pblk_setup_uuid(struct pblk *pblk)
+{
+	uuid_le uuid;
+
+	uuid_le_gen(&uuid);
+	memcpy(pblk->instance_uuid, uuid.b, 16);
+}
+#endif /* PBLK_H_ */