2 * Copyright (C) 2015 IT University of Copenhagen (rrpc.h)
3 * Copyright (C) 2016 CNEX Labs
4 * Initial release: Matias Bjorling <matias@cnexlabs.com>
5 * Write buffering: Javier Gonzalez <javier@cnexlabs.com>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
16 * Implementation of a Physical Block-device target for Open-channel SSDs.
23 #include <linux/blkdev.h>
24 #include <linux/blk-mq.h>
25 #include <linux/bio.h>
26 #include <linux/module.h>
27 #include <linux/kthread.h>
28 #include <linux/vmalloc.h>
29 #include <linux/crc32.h>
30 #include <linux/uuid.h>
32 #include <linux/lightnvm.h>
34 /* Run only GC if less than 1/X blocks are free */
35 #define GC_LIMIT_INVERSE 5
36 #define GC_TIME_MSECS 1000
38 #define PBLK_SECTOR (512)
39 #define PBLK_EXPOSED_PAGE_SIZE (4096)
41 #define PBLK_NR_CLOSE_JOBS (4)
43 #define PBLK_CACHE_NAME_LEN (DISK_NAME_LEN + 16)
45 #define PBLK_COMMAND_TIMEOUT_MS 30000
47 /* Max 512 LUNs per device */
48 #define PBLK_MAX_LUNS_BITMAP (4)
50 #define NR_PHY_IN_LOG (PBLK_EXPOSED_PAGE_SIZE / PBLK_SECTOR)
52 /* Static pool sizes */
53 #define PBLK_GEN_WS_POOL_SIZE (2)
55 #define PBLK_DEFAULT_OP (11)
59 PBLK_WRITE = WRITE,/* Write from write buffer */
60 PBLK_WRITE_INT, /* Internal write - no write buffer */
61 PBLK_READ_RECOV, /* Recovery read - errors allowed */
67 PBLK_IOTYPE_USER = 1 << 0,
68 PBLK_IOTYPE_GC = 1 << 1,
70 /* Write buffer flags */
71 PBLK_FLUSH_ENTRY = 1 << 2,
72 PBLK_WRITTEN_DATA = 1 << 3,
73 PBLK_SUBMITTED_ENTRY = 1 << 4,
74 PBLK_WRITABLE_ENTRY = 1 << 5,
78 PBLK_BLK_ST_OPEN = 0x1,
79 PBLK_BLK_ST_CLOSED = 0x2,
82 struct pblk_sec_meta {
87 /* The number of GC lists and the rate-limiter states go together. This way the
88 * rate-limiter can dictate how much GC is needed based on resource utilization.
90 #define PBLK_GC_NR_LISTS 4
100 #define pblk_dma_meta_size (sizeof(struct pblk_sec_meta) * NVM_MAX_VLBA)
101 #define pblk_dma_ppa_size (sizeof(u64) * NVM_MAX_VLBA)
103 /* write buffer completion context */
105 struct list_head list; /* Head for out-of-order completion */
107 unsigned long *lun_bitmap; /* Luns used on current request */
109 unsigned int nr_valid;
110 unsigned int nr_padded;
116 unsigned long start_time;
120 /* partial read context */
122 struct bio *orig_bio;
123 DECLARE_BITMAP(bitmap, NVM_MAX_VLBA);
124 unsigned int orig_nr_secs;
125 unsigned int bio_init_idx;
127 dma_addr_t dma_ppa_list;
133 struct completion wait;
137 /* Recovery context */
138 struct pblk_rec_ctx {
141 struct work_struct ws_rec;
146 struct bio_list bios; /* Original bios - used for completion
147 * in REQ_FUA, REQ_FLUSH case
149 u64 lba; /* Logic addr. associated with entry */
150 struct ppa_addr ppa; /* Physic addr. associated with entry */
151 int flags; /* Write context flags */
154 struct pblk_rb_entry {
155 struct ppa_addr cacheline; /* Cacheline for this entry */
156 void *data; /* Pointer to data on this entry */
157 struct pblk_w_ctx w_ctx; /* Context for this entry */
158 struct list_head index; /* List head to enable indexes */
161 #define EMPTY_ENTRY (~0U)
163 struct pblk_rb_pages {
166 struct list_head list;
170 struct pblk_rb_entry *entries; /* Ring buffer entries */
171 unsigned int mem; /* Write offset - points to next
172 * writable entry in memory
174 unsigned int subm; /* Read offset - points to last entry
175 * that has been submitted to the media
178 unsigned int sync; /* Synced - backpointer that signals
179 * the last submitted entry that has
180 * been successfully persisted to media
182 unsigned int flush_point; /* Sync point - last entry that must be
183 * flushed to the media. Used with
184 * REQ_FLUSH and REQ_FUA
186 unsigned int l2p_update; /* l2p update point - next entry for
187 * which l2p mapping will be updated to
188 * contain a device ppa address (instead
191 unsigned int nr_entries; /* Number of entries in write buffer -
192 * must be a power of two
194 unsigned int seg_size; /* Size of the data segments being
195 * stored on each entry. Typically this
199 struct list_head pages; /* List of data pages */
201 spinlock_t w_lock; /* Write lock */
202 spinlock_t s_lock; /* Sync lock */
204 #ifdef CONFIG_NVM_PBLK_DEBUG
205 atomic_t inflight_flush_point; /* Not served REQ_FLUSH | REQ_FUA */
209 #define PBLK_RECOVERY_SECTORS 16
212 struct ppa_addr bppa;
213 struct semaphore wr_sem;
217 struct pblk_line *line;
219 u64 paddr_list[NVM_MAX_VLBA];
220 u64 lba_list[NVM_MAX_VLBA];
223 struct list_head list;
227 /* These states are not protected by a lock since (i) they are in the
228 * fast path, and (ii) they are not critical.
234 struct task_struct *gc_ts;
235 struct task_struct *gc_writer_ts;
236 struct task_struct *gc_reader_ts;
238 struct workqueue_struct *gc_line_reader_wq;
239 struct workqueue_struct *gc_reader_wq;
241 struct timer_list gc_timer;
243 struct semaphore gc_sem;
244 atomic_t read_inflight_gc; /* Number of lines with inflight GC reads */
245 atomic_t pipeline_gc; /* Number of lines in the GC pipeline -
246 * started reads to finished writes
250 struct list_head w_list;
251 struct list_head r_list;
259 unsigned int high; /* Upper threshold for rate limiter (free run -
260 * user I/O rate limiter
262 unsigned int high_pw; /* High rounded up as a power of 2 */
264 #define PBLK_USER_HIGH_THRS 8 /* Begin write limit at 12% available blks */
265 #define PBLK_USER_LOW_THRS 10 /* Aggressive GC at 10% available blocks */
267 int rb_windows_pw; /* Number of rate windows in the write buffer
268 * given as a power-of-2. This guarantees that
269 * when user I/O is being rate limited, there
270 * will be reserved enough space for the GC to
271 * place its payload. A window is of
272 * pblk->max_write_pgs size, which in NVMe is
275 int rb_budget; /* Total number of entries available for I/O */
276 int rb_user_max; /* Max buffer entries available for user I/O */
277 int rb_gc_max; /* Max buffer entries available for GC I/O */
278 int rb_gc_rsv; /* Reserved buffer entries for GC I/O */
279 int rb_state; /* Rate-limiter current state */
280 int rb_max_io; /* Maximum size for an I/O giving the config */
282 atomic_t rb_user_cnt; /* User I/O buffer counter */
283 atomic_t rb_gc_cnt; /* GC I/O buffer counter */
284 atomic_t rb_space; /* Space limit in case of reaching capacity */
286 int rsv_blocks; /* Reserved blocks for GC */
291 atomic_t werr_lines; /* Number of write error lines that needs gc */
293 struct timer_list u_timer;
295 unsigned long long nr_secs;
296 unsigned long total_blocks;
298 atomic_t free_blocks; /* Total number of free blocks (+ OP) */
299 atomic_t free_user_blocks; /* Number of user free blocks (no OP) */
302 #define PBLK_LINE_EMPTY (~0U)
306 PBLK_LINETYPE_FREE = 0,
307 PBLK_LINETYPE_LOG = 1,
308 PBLK_LINETYPE_DATA = 2,
311 PBLK_LINESTATE_NEW = 9,
312 PBLK_LINESTATE_FREE = 10,
313 PBLK_LINESTATE_OPEN = 11,
314 PBLK_LINESTATE_CLOSED = 12,
315 PBLK_LINESTATE_GC = 13,
316 PBLK_LINESTATE_BAD = 14,
317 PBLK_LINESTATE_CORRUPT = 15,
320 PBLK_LINEGC_NONE = 20,
321 PBLK_LINEGC_EMPTY = 21,
322 PBLK_LINEGC_LOW = 22,
323 PBLK_LINEGC_MID = 23,
324 PBLK_LINEGC_HIGH = 24,
325 PBLK_LINEGC_FULL = 25,
326 PBLK_LINEGC_WERR = 26
329 #define PBLK_MAGIC 0x70626c6b /*pblk*/
331 /* emeta/smeta persistent storage format versions:
332 * Changes in major version requires offline migration.
333 * Changes in minor version are handled automatically during
337 #define SMETA_VERSION_MAJOR (0)
338 #define SMETA_VERSION_MINOR (1)
340 #define EMETA_VERSION_MAJOR (0)
341 #define EMETA_VERSION_MINOR (2)
345 __le32 identifier; /* pblk identifier */
346 __u8 uuid[16]; /* instance uuid */
347 __le16 type; /* line type */
348 __u8 version_major; /* version major */
349 __u8 version_minor; /* version minor */
350 __le32 id; /* line id for current line */
354 struct line_header header;
356 __le32 crc; /* Full structure including struct crc */
357 /* Previous line metadata */
358 __le32 prev_id; /* Line id for previous line */
360 /* Current line metadata */
361 __le64 seq_nr; /* Sequence number for current line */
364 __le32 window_wr_lun; /* Number of parallel LUNs to write */
373 * Metadata layout in media:
375 * 1. struct line_emeta
376 * 2. bad block bitmap (u64 * window_wr_lun)
377 * 3. write amplification counters
378 * Mid sectors (start at lbas_sector):
379 * 3. nr_lbas (u64) forming lba list
380 * Last sectors (start at vsc_sector):
381 * 4. u32 valid sector count (vsc) for all lines (~0U: free line)
384 struct line_header header;
386 __le32 crc; /* Full structure including struct crc */
388 /* Previous line metadata */
389 __le32 prev_id; /* Line id for prev line */
391 /* Current line metadata */
392 __le64 seq_nr; /* Sequence number for current line */
395 __le32 window_wr_lun; /* Number of parallel LUNs to write */
397 /* Bookkeeping for recovery */
398 __le32 next_id; /* Line id for next line */
399 __le64 nr_lbas; /* Number of lbas mapped in line */
400 __le64 nr_valid_lbas; /* Number of valid lbas mapped in line */
401 __le64 bb_bitmap[]; /* Updated bad block bitmap for line */
405 /* Write amplification counters stored on media */
407 __le64 user; /* Number of user written sectors */
408 __le64 gc; /* Number of sectors written by GC*/
409 __le64 pad; /* Number of padded sectors */
413 struct line_emeta *buf; /* emeta buffer in media format */
414 int mem; /* Write offset - points to next
415 * writable entry in memory
417 atomic_t sync; /* Synced - backpointer that signals the
418 * last entry that has been successfully
421 unsigned int nr_entries; /* Number of emeta entries */
425 struct line_smeta *buf; /* smeta buffer in persistent format */
428 struct pblk_w_err_gc {
435 unsigned int id; /* Line number corresponds to the
438 unsigned int seq_nr; /* Unique line sequence number */
440 int state; /* PBLK_LINESTATE_X */
441 int type; /* PBLK_LINETYPE_X */
442 int gc_group; /* PBLK_LINEGC_X */
443 struct list_head list; /* Free, GC lists */
445 unsigned long *lun_bitmap; /* Bitmap for LUNs mapped in line */
447 struct nvm_chk_meta *chks; /* Chunks forming line */
449 struct pblk_smeta *smeta; /* Start metadata */
450 struct pblk_emeta *emeta; /* End medatada */
452 int meta_line; /* Metadata line id */
453 int meta_distance; /* Distance between data and metadata */
455 u64 smeta_ssec; /* Sector where smeta starts */
456 u64 emeta_ssec; /* Sector where emeta starts */
458 unsigned int sec_in_line; /* Number of usable secs in line */
460 atomic_t blk_in_line; /* Number of good blocks in line */
461 unsigned long *blk_bitmap; /* Bitmap for valid/invalid blocks */
462 unsigned long *erase_bitmap; /* Bitmap for erased blocks */
464 unsigned long *map_bitmap; /* Bitmap for mapped sectors in line */
465 unsigned long *invalid_bitmap; /* Bitmap for invalid sectors in line */
467 atomic_t left_eblks; /* Blocks left for erasing */
468 atomic_t left_seblks; /* Blocks left for sync erasing */
470 int left_msecs; /* Sectors left for mapping */
471 unsigned int cur_sec; /* Sector map pointer */
472 unsigned int nr_valid_lbas; /* Number of valid lbas in line */
474 __le32 *vsc; /* Valid sector count in line */
476 struct kref ref; /* Write buffer L2P references */
478 struct pblk_w_err_gc *w_err_gc; /* Write error gc recovery metadata */
480 spinlock_t lock; /* Necessary for invalid_bitmap only */
483 #define PBLK_DATA_LINES 4
486 PBLK_KMALLOC_META = 1,
487 PBLK_VMALLOC_META = 2,
491 PBLK_EMETA_TYPE_HEADER = 1, /* struct line_emeta first sector */
492 PBLK_EMETA_TYPE_LLBA = 2, /* lba list - type: __le64 */
493 PBLK_EMETA_TYPE_VSC = 3, /* vsc list - type: __le32 */
496 struct pblk_line_mgmt {
497 int nr_lines; /* Total number of full lines */
498 int nr_free_lines; /* Number of full lines in free list */
500 /* Free lists - use free_lock */
501 struct list_head free_list; /* Full lines ready to use */
502 struct list_head corrupt_list; /* Full lines corrupted */
503 struct list_head bad_list; /* Full lines bad */
505 /* GC lists - use gc_lock */
506 struct list_head *gc_lists[PBLK_GC_NR_LISTS];
507 struct list_head gc_high_list; /* Full lines ready to GC, high isc */
508 struct list_head gc_mid_list; /* Full lines ready to GC, mid isc */
509 struct list_head gc_low_list; /* Full lines ready to GC, low isc */
511 struct list_head gc_werr_list; /* Write err recovery list */
513 struct list_head gc_full_list; /* Full lines ready to GC, no valid */
514 struct list_head gc_empty_list; /* Full lines close, all valid */
516 struct pblk_line *log_line; /* Current FTL log line */
517 struct pblk_line *data_line; /* Current data line */
518 struct pblk_line *log_next; /* Next FTL log line */
519 struct pblk_line *data_next; /* Next data line */
521 struct list_head emeta_list; /* Lines queued to schedule emeta */
523 __le32 *vsc_list; /* Valid sector counts for all lines */
525 /* Metadata allocation type: VMALLOC | KMALLOC */
526 int emeta_alloc_type;
528 /* Pre-allocated metadata for data lines */
529 struct pblk_smeta *sline_meta[PBLK_DATA_LINES];
530 struct pblk_emeta *eline_meta[PBLK_DATA_LINES];
531 unsigned long meta_bitmap;
533 /* Cache and mempool for map/invalid bitmaps */
534 struct kmem_cache *bitmap_cache;
535 mempool_t *bitmap_pool;
537 /* Helpers for fast bitmap calculations */
538 unsigned long *bb_template;
539 unsigned long *bb_aux;
541 unsigned long d_seq_nr; /* Data line unique sequence number */
542 unsigned long l_seq_nr; /* Log line unique sequence number */
544 spinlock_t free_lock;
545 spinlock_t close_lock;
549 struct pblk_line_meta {
550 unsigned int smeta_len; /* Total length for smeta */
551 unsigned int smeta_sec; /* Sectors needed for smeta */
553 unsigned int emeta_len[4]; /* Lengths for emeta:
555 * [1]: struct line_emeta +
556 * bb_bitmap + struct wa_counters
560 unsigned int emeta_sec[4]; /* Sectors needed for emeta. Same layout
564 unsigned int emeta_bb; /* Boundary for bb that affects emeta */
566 unsigned int vsc_list_len; /* Length for vsc list */
567 unsigned int sec_bitmap_len; /* Length for sector bitmap in line */
568 unsigned int blk_bitmap_len; /* Length for block bitmap in line */
569 unsigned int lun_bitmap_len; /* Length for lun bitmap in line */
571 unsigned int blk_per_line; /* Number of blocks in a full line */
572 unsigned int sec_per_line; /* Number of sectors in a line */
573 unsigned int dsec_per_line; /* Number of data sectors in a line */
574 unsigned int min_blk_line; /* Min. number of good blocks in line */
576 unsigned int mid_thrs; /* Threshold for GC mid list */
577 unsigned int high_thrs; /* Threshold for GC high list */
579 unsigned int meta_distance; /* Distance between data and metadata */
583 PBLK_STATE_RUNNING = 0,
584 PBLK_STATE_STOPPING = 1,
585 PBLK_STATE_RECOVERING = 2,
586 PBLK_STATE_STOPPED = 3,
589 /* Internal format to support not power-of-2 device formats */
602 struct nvm_tgt_dev *dev;
603 struct gendisk *disk;
607 struct pblk_lun *luns;
609 struct pblk_line *lines; /* Line array */
610 struct pblk_line_mgmt l_mg; /* Line management */
611 struct pblk_line_meta lm; /* Line metadata */
613 struct nvm_addrf addrf; /* Aligned address format */
614 struct pblk_addrf uaddrf; /* Unaligned address format */
619 int state; /* pblk line state */
621 int min_write_pgs; /* Minimum amount of pages required by controller */
622 int max_write_pgs; /* Maximum amount of pages supported by controller */
624 sector_t capacity; /* Device capacity when bad blocks are subtracted */
626 int op; /* Percentage of device used for over-provisioning */
627 int op_blks; /* Number of blocks used for over-provisioning */
629 /* pblk provisioning values. Used by rate limiter */
634 unsigned char instance_uuid[16];
636 /* Persistent write amplification counters, 4kb sector I/Os */
637 atomic64_t user_wa; /* Sectors written by user */
638 atomic64_t gc_wa; /* Sectors written by GC */
639 atomic64_t pad_wa; /* Padded sectors written */
641 /* Reset values for delta write amplification measurements */
646 /* Counters used for calculating padding distribution */
647 atomic64_t *pad_dist; /* Padding distribution buckets */
648 u64 nr_flush_rst; /* Flushes reset value for pad dist.*/
649 atomic64_t nr_flush; /* Number of flush/fua I/O */
651 #ifdef CONFIG_NVM_PBLK_DEBUG
652 /* Non-persistent debug counters, 4kb sector I/Os */
653 atomic_long_t inflight_writes; /* Inflight writes (user and gc) */
654 atomic_long_t padded_writes; /* Sectors padded due to flush/fua */
655 atomic_long_t padded_wb; /* Sectors padded in write buffer */
656 atomic_long_t req_writes; /* Sectors stored on write buffer */
657 atomic_long_t sub_writes; /* Sectors submitted from buffer */
658 atomic_long_t sync_writes; /* Sectors synced to media */
659 atomic_long_t inflight_reads; /* Inflight sector read requests */
660 atomic_long_t cache_reads; /* Read requests that hit the cache */
661 atomic_long_t sync_reads; /* Completed sector read requests */
662 atomic_long_t recov_writes; /* Sectors submitted from recovery */
663 atomic_long_t recov_gc_writes; /* Sectors submitted from write GC */
664 atomic_long_t recov_gc_reads; /* Sectors submitted from read GC */
669 atomic_long_t read_failed;
670 atomic_long_t read_empty;
671 atomic_long_t read_high_ecc;
672 atomic_long_t read_failed_gc;
673 atomic_long_t write_failed;
674 atomic_long_t erase_failed;
676 atomic_t inflight_io; /* General inflight I/O counter */
678 struct task_struct *writer_ts;
680 /* Simple translation map of logical addresses to physical addresses.
681 * The logical addresses is known by the host system, while the physical
682 * addresses are used when writing to the disk block device.
684 unsigned char *trans_map;
685 spinlock_t trans_lock;
687 struct list_head compl_list;
689 spinlock_t resubmit_lock; /* Resubmit list lock */
690 struct list_head resubmit_list; /* Resubmit list for failed writes*/
692 mempool_t page_bio_pool;
693 mempool_t gen_ws_pool;
699 struct workqueue_struct *close_wq;
700 struct workqueue_struct *bb_wq;
701 struct workqueue_struct *r_end_wq;
703 struct timer_list wtimer;
708 struct pblk_line_ws {
710 struct pblk_line *line;
712 struct work_struct ws;
715 #define pblk_g_rq_size (sizeof(struct nvm_rq) + sizeof(struct pblk_g_ctx))
716 #define pblk_w_rq_size (sizeof(struct nvm_rq) + sizeof(struct pblk_c_ctx))
718 #define pblk_err(pblk, fmt, ...) \
719 pr_err("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
720 #define pblk_info(pblk, fmt, ...) \
721 pr_info("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
722 #define pblk_warn(pblk, fmt, ...) \
723 pr_warn("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
724 #define pblk_debug(pblk, fmt, ...) \
725 pr_debug("pblk %s: " fmt, pblk->disk->disk_name, ##__VA_ARGS__)
728 * pblk ring buffer operations
730 int pblk_rb_init(struct pblk_rb *rb, struct pblk_rb_entry *rb_entry_base,
731 unsigned int power_size, unsigned int power_seg_sz);
732 unsigned int pblk_rb_calculate_size(unsigned int nr_entries);
733 void *pblk_rb_entries_ref(struct pblk_rb *rb);
734 int pblk_rb_may_write_user(struct pblk_rb *rb, struct bio *bio,
735 unsigned int nr_entries, unsigned int *pos);
736 int pblk_rb_may_write_gc(struct pblk_rb *rb, unsigned int nr_entries,
738 void pblk_rb_write_entry_user(struct pblk_rb *rb, void *data,
739 struct pblk_w_ctx w_ctx, unsigned int pos);
740 void pblk_rb_write_entry_gc(struct pblk_rb *rb, void *data,
741 struct pblk_w_ctx w_ctx, struct pblk_line *line,
742 u64 paddr, unsigned int pos);
743 struct pblk_w_ctx *pblk_rb_w_ctx(struct pblk_rb *rb, unsigned int pos);
744 void pblk_rb_flush(struct pblk_rb *rb);
746 void pblk_rb_sync_l2p(struct pblk_rb *rb);
747 unsigned int pblk_rb_read_to_bio(struct pblk_rb *rb, struct nvm_rq *rqd,
748 unsigned int pos, unsigned int nr_entries,
750 int pblk_rb_copy_to_bio(struct pblk_rb *rb, struct bio *bio, sector_t lba,
751 struct ppa_addr ppa, int bio_iter, bool advanced_bio);
752 unsigned int pblk_rb_read_commit(struct pblk_rb *rb, unsigned int entries);
754 unsigned int pblk_rb_sync_init(struct pblk_rb *rb, unsigned long *flags);
755 unsigned int pblk_rb_sync_advance(struct pblk_rb *rb, unsigned int nr_entries);
756 struct pblk_rb_entry *pblk_rb_sync_scan_entry(struct pblk_rb *rb,
757 struct ppa_addr *ppa);
758 void pblk_rb_sync_end(struct pblk_rb *rb, unsigned long *flags);
759 unsigned int pblk_rb_flush_point_count(struct pblk_rb *rb);
761 unsigned int pblk_rb_read_count(struct pblk_rb *rb);
762 unsigned int pblk_rb_sync_count(struct pblk_rb *rb);
763 unsigned int pblk_rb_wrap_pos(struct pblk_rb *rb, unsigned int pos);
765 int pblk_rb_tear_down_check(struct pblk_rb *rb);
766 int pblk_rb_pos_oob(struct pblk_rb *rb, u64 pos);
767 void pblk_rb_data_free(struct pblk_rb *rb);
768 ssize_t pblk_rb_sysfs(struct pblk_rb *rb, char *buf);
773 struct nvm_rq *pblk_alloc_rqd(struct pblk *pblk, int type);
774 void pblk_free_rqd(struct pblk *pblk, struct nvm_rq *rqd, int type);
775 void pblk_set_sec_per_write(struct pblk *pblk, int sec_per_write);
776 int pblk_setup_w_rec_rq(struct pblk *pblk, struct nvm_rq *rqd,
777 struct pblk_c_ctx *c_ctx);
778 void pblk_discard(struct pblk *pblk, struct bio *bio);
779 struct nvm_chk_meta *pblk_get_chunk_meta(struct pblk *pblk);
780 struct nvm_chk_meta *pblk_chunk_get_off(struct pblk *pblk,
781 struct nvm_chk_meta *lp,
782 struct ppa_addr ppa);
783 void pblk_log_write_err(struct pblk *pblk, struct nvm_rq *rqd);
784 void pblk_log_read_err(struct pblk *pblk, struct nvm_rq *rqd);
785 int pblk_submit_io(struct pblk *pblk, struct nvm_rq *rqd);
786 int pblk_submit_io_sync(struct pblk *pblk, struct nvm_rq *rqd);
787 int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line);
788 struct bio *pblk_bio_map_addr(struct pblk *pblk, void *data,
789 unsigned int nr_secs, unsigned int len,
790 int alloc_type, gfp_t gfp_mask);
791 struct pblk_line *pblk_line_get(struct pblk *pblk);
792 struct pblk_line *pblk_line_get_first_data(struct pblk *pblk);
793 struct pblk_line *pblk_line_replace_data(struct pblk *pblk);
794 void pblk_ppa_to_line_put(struct pblk *pblk, struct ppa_addr ppa);
795 void pblk_rq_to_line_put(struct pblk *pblk, struct nvm_rq *rqd);
796 int pblk_line_recov_alloc(struct pblk *pblk, struct pblk_line *line);
797 void pblk_line_recov_close(struct pblk *pblk, struct pblk_line *line);
798 struct pblk_line *pblk_line_get_data(struct pblk *pblk);
799 struct pblk_line *pblk_line_get_erase(struct pblk *pblk);
800 int pblk_line_erase(struct pblk *pblk, struct pblk_line *line);
801 int pblk_line_is_full(struct pblk_line *line);
802 void pblk_line_free(struct pblk_line *line);
803 void pblk_line_close_meta(struct pblk *pblk, struct pblk_line *line);
804 void pblk_line_close(struct pblk *pblk, struct pblk_line *line);
805 void pblk_line_close_ws(struct work_struct *work);
806 void pblk_pipeline_stop(struct pblk *pblk);
807 void __pblk_pipeline_stop(struct pblk *pblk);
808 void __pblk_pipeline_flush(struct pblk *pblk);
809 void pblk_gen_run_ws(struct pblk *pblk, struct pblk_line *line, void *priv,
810 void (*work)(struct work_struct *), gfp_t gfp_mask,
811 struct workqueue_struct *wq);
812 u64 pblk_line_smeta_start(struct pblk *pblk, struct pblk_line *line);
813 int pblk_line_read_smeta(struct pblk *pblk, struct pblk_line *line);
814 int pblk_line_read_emeta(struct pblk *pblk, struct pblk_line *line,
816 int pblk_blk_erase_async(struct pblk *pblk, struct ppa_addr erase_ppa);
817 void pblk_line_put(struct kref *ref);
818 void pblk_line_put_wq(struct kref *ref);
819 struct list_head *pblk_line_gc_list(struct pblk *pblk, struct pblk_line *line);
820 u64 pblk_lookup_page(struct pblk *pblk, struct pblk_line *line);
821 void pblk_dealloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs);
822 u64 pblk_alloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs);
823 u64 __pblk_alloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs);
824 int pblk_calc_secs(struct pblk *pblk, unsigned long secs_avail,
825 unsigned long secs_to_flush);
826 void pblk_down_rq(struct pblk *pblk, struct ppa_addr ppa,
827 unsigned long *lun_bitmap);
828 void pblk_down_chunk(struct pblk *pblk, struct ppa_addr ppa);
829 void pblk_up_chunk(struct pblk *pblk, struct ppa_addr ppa);
830 void pblk_up_rq(struct pblk *pblk, unsigned long *lun_bitmap);
831 int pblk_bio_add_pages(struct pblk *pblk, struct bio *bio, gfp_t flags,
833 void pblk_bio_free_pages(struct pblk *pblk, struct bio *bio, int off,
835 void pblk_map_invalidate(struct pblk *pblk, struct ppa_addr ppa);
836 void __pblk_map_invalidate(struct pblk *pblk, struct pblk_line *line,
838 void pblk_update_map(struct pblk *pblk, sector_t lba, struct ppa_addr ppa);
839 void pblk_update_map_cache(struct pblk *pblk, sector_t lba,
840 struct ppa_addr ppa);
841 void pblk_update_map_dev(struct pblk *pblk, sector_t lba,
842 struct ppa_addr ppa, struct ppa_addr entry_line);
843 int pblk_update_map_gc(struct pblk *pblk, sector_t lba, struct ppa_addr ppa,
844 struct pblk_line *gc_line, u64 paddr);
845 void pblk_lookup_l2p_rand(struct pblk *pblk, struct ppa_addr *ppas,
846 u64 *lba_list, int nr_secs);
847 void pblk_lookup_l2p_seq(struct pblk *pblk, struct ppa_addr *ppas,
848 sector_t blba, int nr_secs);
851 * pblk user I/O write path
853 int pblk_write_to_cache(struct pblk *pblk, struct bio *bio,
854 unsigned long flags);
855 int pblk_write_gc_to_cache(struct pblk *pblk, struct pblk_gc_rq *gc_rq);
860 void pblk_map_erase_rq(struct pblk *pblk, struct nvm_rq *rqd,
861 unsigned int sentry, unsigned long *lun_bitmap,
862 unsigned int valid_secs, struct ppa_addr *erase_ppa);
863 void pblk_map_rq(struct pblk *pblk, struct nvm_rq *rqd, unsigned int sentry,
864 unsigned long *lun_bitmap, unsigned int valid_secs,
870 int pblk_write_ts(void *data);
871 void pblk_write_timer_fn(struct timer_list *t);
872 void pblk_write_should_kick(struct pblk *pblk);
873 void pblk_write_kick(struct pblk *pblk);
878 extern struct bio_set pblk_bio_set;
879 int pblk_submit_read(struct pblk *pblk, struct bio *bio);
880 int pblk_submit_read_gc(struct pblk *pblk, struct pblk_gc_rq *gc_rq);
884 struct pblk_line *pblk_recov_l2p(struct pblk *pblk);
885 int pblk_recov_pad(struct pblk *pblk);
886 int pblk_recov_check_emeta(struct pblk *pblk, struct line_emeta *emeta);
891 #define PBLK_GC_MAX_READERS 8 /* Max number of outstanding GC reader jobs */
892 #define PBLK_GC_RQ_QD 128 /* Queue depth for inflight GC requests */
893 #define PBLK_GC_L_QD 4 /* Queue depth for inflight GC lines */
894 #define PBLK_GC_RSV_LINE 1 /* Reserved lines for GC */
896 int pblk_gc_init(struct pblk *pblk);
897 void pblk_gc_exit(struct pblk *pblk, bool graceful);
898 void pblk_gc_should_start(struct pblk *pblk);
899 void pblk_gc_should_stop(struct pblk *pblk);
900 void pblk_gc_should_kick(struct pblk *pblk);
901 void pblk_gc_free_full_lines(struct pblk *pblk);
902 void pblk_gc_sysfs_state_show(struct pblk *pblk, int *gc_enabled,
904 int pblk_gc_sysfs_force(struct pblk *pblk, int force);
909 void pblk_rl_init(struct pblk_rl *rl, int budget);
910 void pblk_rl_free(struct pblk_rl *rl);
911 void pblk_rl_update_rates(struct pblk_rl *rl);
912 int pblk_rl_high_thrs(struct pblk_rl *rl);
913 unsigned long pblk_rl_nr_free_blks(struct pblk_rl *rl);
914 unsigned long pblk_rl_nr_user_free_blks(struct pblk_rl *rl);
915 int pblk_rl_user_may_insert(struct pblk_rl *rl, int nr_entries);
916 void pblk_rl_inserted(struct pblk_rl *rl, int nr_entries);
917 void pblk_rl_user_in(struct pblk_rl *rl, int nr_entries);
918 int pblk_rl_gc_may_insert(struct pblk_rl *rl, int nr_entries);
919 void pblk_rl_gc_in(struct pblk_rl *rl, int nr_entries);
920 void pblk_rl_out(struct pblk_rl *rl, int nr_user, int nr_gc);
921 int pblk_rl_max_io(struct pblk_rl *rl);
922 void pblk_rl_free_lines_inc(struct pblk_rl *rl, struct pblk_line *line);
923 void pblk_rl_free_lines_dec(struct pblk_rl *rl, struct pblk_line *line,
925 int pblk_rl_is_limit(struct pblk_rl *rl);
927 void pblk_rl_werr_line_in(struct pblk_rl *rl);
928 void pblk_rl_werr_line_out(struct pblk_rl *rl);
933 int pblk_sysfs_init(struct gendisk *tdisk);
934 void pblk_sysfs_exit(struct gendisk *tdisk);
936 static inline void *pblk_malloc(size_t size, int type, gfp_t flags)
938 if (type == PBLK_KMALLOC_META)
939 return kmalloc(size, flags);
940 return vmalloc(size);
943 static inline void pblk_mfree(void *ptr, int type)
945 if (type == PBLK_KMALLOC_META)
951 static inline struct nvm_rq *nvm_rq_from_c_ctx(void *c_ctx)
953 return c_ctx - sizeof(struct nvm_rq);
956 static inline void *emeta_to_bb(struct line_emeta *emeta)
958 return emeta->bb_bitmap;
961 static inline void *emeta_to_wa(struct pblk_line_meta *lm,
962 struct line_emeta *emeta)
964 return emeta->bb_bitmap + lm->blk_bitmap_len;
967 static inline void *emeta_to_lbas(struct pblk *pblk, struct line_emeta *emeta)
969 return ((void *)emeta + pblk->lm.emeta_len[1]);
972 static inline void *emeta_to_vsc(struct pblk *pblk, struct line_emeta *emeta)
974 return (emeta_to_lbas(pblk, emeta) + pblk->lm.emeta_len[2]);
977 static inline int pblk_line_vsc(struct pblk_line *line)
979 return le32_to_cpu(*line->vsc);
982 static inline int pblk_pad_distance(struct pblk *pblk)
984 struct nvm_tgt_dev *dev = pblk->dev;
985 struct nvm_geo *geo = &dev->geo;
987 return geo->mw_cunits * geo->all_luns * geo->ws_opt;
990 static inline int pblk_ppa_to_line_id(struct ppa_addr p)
995 static inline struct pblk_line *pblk_ppa_to_line(struct pblk *pblk,
998 return &pblk->lines[pblk_ppa_to_line_id(p)];
1001 static inline int pblk_ppa_to_pos(struct nvm_geo *geo, struct ppa_addr p)
1003 return p.a.lun * geo->num_ch + p.a.ch;
1006 static inline struct ppa_addr addr_to_gen_ppa(struct pblk *pblk, u64 paddr,
1009 struct nvm_tgt_dev *dev = pblk->dev;
1010 struct nvm_geo *geo = &dev->geo;
1011 struct ppa_addr ppa;
1013 if (geo->version == NVM_OCSSD_SPEC_12) {
1014 struct nvm_addrf_12 *ppaf = (struct nvm_addrf_12 *)&pblk->addrf;
1017 ppa.g.blk = line_id;
1018 ppa.g.pg = (paddr & ppaf->pg_mask) >> ppaf->pg_offset;
1019 ppa.g.lun = (paddr & ppaf->lun_mask) >> ppaf->lun_offset;
1020 ppa.g.ch = (paddr & ppaf->ch_mask) >> ppaf->ch_offset;
1021 ppa.g.pl = (paddr & ppaf->pln_mask) >> ppaf->pln_offset;
1022 ppa.g.sec = (paddr & ppaf->sec_mask) >> ppaf->sec_offset;
1024 struct pblk_addrf *uaddrf = &pblk->uaddrf;
1025 int secs, chnls, luns;
1029 ppa.m.chk = line_id;
1031 paddr = div_u64_rem(paddr, uaddrf->sec_stripe, &secs);
1034 paddr = div_u64_rem(paddr, uaddrf->ch_stripe, &chnls);
1037 paddr = div_u64_rem(paddr, uaddrf->lun_stripe, &luns);
1040 ppa.m.sec += uaddrf->sec_stripe * paddr;
1046 static inline struct nvm_chk_meta *pblk_dev_ppa_to_chunk(struct pblk *pblk,
1049 struct nvm_tgt_dev *dev = pblk->dev;
1050 struct nvm_geo *geo = &dev->geo;
1051 struct pblk_line *line = pblk_ppa_to_line(pblk, p);
1052 int pos = pblk_ppa_to_pos(geo, p);
1054 return &line->chks[pos];
1057 static inline u64 pblk_dev_ppa_to_chunk_addr(struct pblk *pblk,
1060 struct nvm_tgt_dev *dev = pblk->dev;
1062 return dev_to_chunk_addr(dev->parent, &pblk->addrf, p);
1065 static inline u64 pblk_dev_ppa_to_line_addr(struct pblk *pblk,
1068 struct nvm_tgt_dev *dev = pblk->dev;
1069 struct nvm_geo *geo = &dev->geo;
1072 if (geo->version == NVM_OCSSD_SPEC_12) {
1073 struct nvm_addrf_12 *ppaf = (struct nvm_addrf_12 *)&pblk->addrf;
1075 paddr = (u64)p.g.ch << ppaf->ch_offset;
1076 paddr |= (u64)p.g.lun << ppaf->lun_offset;
1077 paddr |= (u64)p.g.pg << ppaf->pg_offset;
1078 paddr |= (u64)p.g.pl << ppaf->pln_offset;
1079 paddr |= (u64)p.g.sec << ppaf->sec_offset;
1081 struct pblk_addrf *uaddrf = &pblk->uaddrf;
1085 paddr = (u64)p.m.grp * uaddrf->sec_stripe;
1086 paddr += (u64)p.m.pu * uaddrf->sec_lun_stripe;
1088 secs = div_u64_rem(secs, uaddrf->sec_stripe, &sec_stripe);
1089 paddr += secs * uaddrf->sec_ws_stripe;
1090 paddr += sec_stripe;
1096 static inline struct ppa_addr pblk_ppa32_to_ppa64(struct pblk *pblk, u32 ppa32)
1098 struct ppa_addr ppa64;
1103 ppa64.ppa = ADDR_EMPTY;
1104 } else if (ppa32 & (1U << 31)) {
1105 ppa64.c.line = ppa32 & ((~0U) >> 1);
1106 ppa64.c.is_cached = 1;
1108 struct nvm_tgt_dev *dev = pblk->dev;
1109 struct nvm_geo *geo = &dev->geo;
1111 if (geo->version == NVM_OCSSD_SPEC_12) {
1112 struct nvm_addrf_12 *ppaf =
1113 (struct nvm_addrf_12 *)&pblk->addrf;
1115 ppa64.g.ch = (ppa32 & ppaf->ch_mask) >>
1117 ppa64.g.lun = (ppa32 & ppaf->lun_mask) >>
1119 ppa64.g.blk = (ppa32 & ppaf->blk_mask) >>
1121 ppa64.g.pg = (ppa32 & ppaf->pg_mask) >>
1123 ppa64.g.pl = (ppa32 & ppaf->pln_mask) >>
1125 ppa64.g.sec = (ppa32 & ppaf->sec_mask) >>
1128 struct nvm_addrf *lbaf = &pblk->addrf;
1130 ppa64.m.grp = (ppa32 & lbaf->ch_mask) >>
1132 ppa64.m.pu = (ppa32 & lbaf->lun_mask) >>
1134 ppa64.m.chk = (ppa32 & lbaf->chk_mask) >>
1136 ppa64.m.sec = (ppa32 & lbaf->sec_mask) >>
1144 static inline u32 pblk_ppa64_to_ppa32(struct pblk *pblk, struct ppa_addr ppa64)
1148 if (ppa64.ppa == ADDR_EMPTY) {
1150 } else if (ppa64.c.is_cached) {
1151 ppa32 |= ppa64.c.line;
1154 struct nvm_tgt_dev *dev = pblk->dev;
1155 struct nvm_geo *geo = &dev->geo;
1157 if (geo->version == NVM_OCSSD_SPEC_12) {
1158 struct nvm_addrf_12 *ppaf =
1159 (struct nvm_addrf_12 *)&pblk->addrf;
1161 ppa32 |= ppa64.g.ch << ppaf->ch_offset;
1162 ppa32 |= ppa64.g.lun << ppaf->lun_offset;
1163 ppa32 |= ppa64.g.blk << ppaf->blk_offset;
1164 ppa32 |= ppa64.g.pg << ppaf->pg_offset;
1165 ppa32 |= ppa64.g.pl << ppaf->pln_offset;
1166 ppa32 |= ppa64.g.sec << ppaf->sec_offset;
1168 struct nvm_addrf *lbaf = &pblk->addrf;
1170 ppa32 |= ppa64.m.grp << lbaf->ch_offset;
1171 ppa32 |= ppa64.m.pu << lbaf->lun_offset;
1172 ppa32 |= ppa64.m.chk << lbaf->chk_offset;
1173 ppa32 |= ppa64.m.sec << lbaf->sec_offset;
1180 static inline struct ppa_addr pblk_trans_map_get(struct pblk *pblk,
1183 struct ppa_addr ppa;
1185 if (pblk->addrf_len < 32) {
1186 u32 *map = (u32 *)pblk->trans_map;
1188 ppa = pblk_ppa32_to_ppa64(pblk, map[lba]);
1190 struct ppa_addr *map = (struct ppa_addr *)pblk->trans_map;
1198 static inline void pblk_trans_map_set(struct pblk *pblk, sector_t lba,
1199 struct ppa_addr ppa)
1201 if (pblk->addrf_len < 32) {
1202 u32 *map = (u32 *)pblk->trans_map;
1204 map[lba] = pblk_ppa64_to_ppa32(pblk, ppa);
1206 u64 *map = (u64 *)pblk->trans_map;
1212 static inline int pblk_ppa_empty(struct ppa_addr ppa_addr)
1214 return (ppa_addr.ppa == ADDR_EMPTY);
1217 static inline void pblk_ppa_set_empty(struct ppa_addr *ppa_addr)
1219 ppa_addr->ppa = ADDR_EMPTY;
1222 static inline bool pblk_ppa_comp(struct ppa_addr lppa, struct ppa_addr rppa)
1224 return (lppa.ppa == rppa.ppa);
1227 static inline int pblk_addr_in_cache(struct ppa_addr ppa)
1229 return (ppa.ppa != ADDR_EMPTY && ppa.c.is_cached);
1232 static inline int pblk_addr_to_cacheline(struct ppa_addr ppa)
1237 static inline struct ppa_addr pblk_cacheline_to_addr(int addr)
1247 static inline u32 pblk_calc_meta_header_crc(struct pblk *pblk,
1248 struct line_header *header)
1252 crc = crc32_le(crc, (unsigned char *)header + sizeof(crc),
1253 sizeof(struct line_header) - sizeof(crc));
1258 static inline u32 pblk_calc_smeta_crc(struct pblk *pblk,
1259 struct line_smeta *smeta)
1261 struct pblk_line_meta *lm = &pblk->lm;
1264 crc = crc32_le(crc, (unsigned char *)smeta +
1265 sizeof(struct line_header) + sizeof(crc),
1267 sizeof(struct line_header) - sizeof(crc));
1272 static inline u32 pblk_calc_emeta_crc(struct pblk *pblk,
1273 struct line_emeta *emeta)
1275 struct pblk_line_meta *lm = &pblk->lm;
1278 crc = crc32_le(crc, (unsigned char *)emeta +
1279 sizeof(struct line_header) + sizeof(crc),
1281 sizeof(struct line_header) - sizeof(crc));
1286 static inline int pblk_io_aligned(struct pblk *pblk, int nr_secs)
1288 return !(nr_secs % pblk->min_write_pgs);
1291 #ifdef CONFIG_NVM_PBLK_DEBUG
1292 static inline void print_ppa(struct pblk *pblk, struct ppa_addr *p,
1293 char *msg, int error)
1295 struct nvm_geo *geo = &pblk->dev->geo;
1297 if (p->c.is_cached) {
1298 pblk_err(pblk, "ppa: (%s: %x) cache line: %llu\n",
1299 msg, error, (u64)p->c.line);
1300 } else if (geo->version == NVM_OCSSD_SPEC_12) {
1301 pblk_err(pblk, "ppa: (%s: %x):ch:%d,lun:%d,blk:%d,pg:%d,pl:%d,sec:%d\n",
1303 p->g.ch, p->g.lun, p->g.blk,
1304 p->g.pg, p->g.pl, p->g.sec);
1306 pblk_err(pblk, "ppa: (%s: %x):ch:%d,lun:%d,chk:%d,sec:%d\n",
1308 p->m.grp, p->m.pu, p->m.chk, p->m.sec);
1312 static inline void pblk_print_failed_rqd(struct pblk *pblk, struct nvm_rq *rqd,
1317 if (rqd->nr_ppas == 1) {
1318 print_ppa(pblk, &rqd->ppa_addr, "rqd", error);
1322 while ((bit = find_next_bit((void *)&rqd->ppa_status, rqd->nr_ppas,
1323 bit + 1)) < rqd->nr_ppas) {
1324 print_ppa(pblk, &rqd->ppa_list[bit], "rqd", error);
1327 pblk_err(pblk, "error:%d, ppa_status:%llx\n", error, rqd->ppa_status);
1330 static inline int pblk_boundary_ppa_checks(struct nvm_tgt_dev *tgt_dev,
1331 struct ppa_addr *ppas, int nr_ppas)
1333 struct nvm_geo *geo = &tgt_dev->geo;
1334 struct ppa_addr *ppa;
1337 for (i = 0; i < nr_ppas; i++) {
1340 if (geo->version == NVM_OCSSD_SPEC_12) {
1341 if (!ppa->c.is_cached &&
1342 ppa->g.ch < geo->num_ch &&
1343 ppa->g.lun < geo->num_lun &&
1344 ppa->g.pl < geo->num_pln &&
1345 ppa->g.blk < geo->num_chk &&
1346 ppa->g.pg < geo->num_pg &&
1347 ppa->g.sec < geo->ws_min)
1350 if (!ppa->c.is_cached &&
1351 ppa->m.grp < geo->num_ch &&
1352 ppa->m.pu < geo->num_lun &&
1353 ppa->m.chk < geo->num_chk &&
1354 ppa->m.sec < geo->clba)
1358 print_ppa(tgt_dev->q->queuedata, ppa, "boundary", i);
1365 static inline int pblk_check_io(struct pblk *pblk, struct nvm_rq *rqd)
1367 struct nvm_tgt_dev *dev = pblk->dev;
1368 struct ppa_addr *ppa_list = nvm_rq_to_ppa_list(rqd);
1370 if (pblk_boundary_ppa_checks(dev, ppa_list, rqd->nr_ppas)) {
1375 if (rqd->opcode == NVM_OP_PWRITE) {
1376 struct pblk_line *line;
1379 for (i = 0; i < rqd->nr_ppas; i++) {
1380 line = pblk_ppa_to_line(pblk, ppa_list[i]);
1382 spin_lock(&line->lock);
1383 if (line->state != PBLK_LINESTATE_OPEN) {
1384 pblk_err(pblk, "bad ppa: line:%d,state:%d\n",
1385 line->id, line->state);
1387 spin_unlock(&line->lock);
1390 spin_unlock(&line->lock);
1398 static inline int pblk_boundary_paddr_checks(struct pblk *pblk, u64 paddr)
1400 struct pblk_line_meta *lm = &pblk->lm;
1402 if (paddr > lm->sec_per_line)
1408 static inline unsigned int pblk_get_bi_idx(struct bio *bio)
1410 return bio->bi_iter.bi_idx;
1413 static inline sector_t pblk_get_lba(struct bio *bio)
1415 return bio->bi_iter.bi_sector / NR_PHY_IN_LOG;
1418 static inline unsigned int pblk_get_secs(struct bio *bio)
1420 return bio->bi_iter.bi_size / PBLK_EXPOSED_PAGE_SIZE;
1423 static inline void pblk_setup_uuid(struct pblk *pblk)
1428 memcpy(pblk->instance_uuid, uuid.b, 16);
1430 #endif /* PBLK_H_ */