2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2006, 2007
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 * Author: Artem Bityutskiy (Битюцкий Артём)
25 #include <linux/init.h>
26 #include <linux/types.h>
27 #include <linux/list.h>
28 #include <linux/rbtree.h>
29 #include <linux/sched.h>
30 #include <linux/wait.h>
31 #include <linux/mutex.h>
32 #include <linux/rwsem.h>
33 #include <linux/spinlock.h>
35 #include <linux/cdev.h>
36 #include <linux/device.h>
37 #include <linux/string.h>
38 #include <linux/vmalloc.h>
39 #include <linux/mtd/mtd.h>
40 #include <linux/mtd/ubi.h>
42 #include "ubi-media.h"
46 /* Maximum number of supported UBI devices */
47 #define UBI_MAX_DEVICES 32
49 /* UBI name used for character devices, sysfs, etc */
50 #define UBI_NAME_STR "ubi"
52 /* Normal UBI messages */
53 #define ubi_msg(fmt, ...) printk(KERN_NOTICE "UBI: " fmt "\n", ##__VA_ARGS__)
54 /* UBI warning messages */
55 #define ubi_warn(fmt, ...) printk(KERN_WARNING "UBI warning: %s: " fmt "\n", \
56 __func__, ##__VA_ARGS__)
57 /* UBI error messages */
58 #define ubi_err(fmt, ...) printk(KERN_ERR "UBI error: %s: " fmt "\n", \
59 __func__, ##__VA_ARGS__)
61 /* Lowest number PEBs reserved for bad PEB handling */
62 #define MIN_RESEVED_PEBS 2
64 /* Background thread name pattern */
65 #define UBI_BGT_NAME_PATTERN "ubi_bgt%dd"
67 /* This marker in the EBA table means that the LEB is um-mapped */
68 #define UBI_LEB_UNMAPPED -1
71 * In case of errors, UBI tries to repeat the operation several times before
72 * returning error. The below constant defines how many times UBI re-tries.
74 #define UBI_IO_RETRIES 3
77 * Error codes returned by the I/O sub-system.
79 * UBI_IO_PEB_EMPTY: the physical eraseblock is empty, i.e. it contains only
81 * UBI_IO_PEB_FREE: the physical eraseblock is free, i.e. it contains only a
82 * valid erase counter header, and the rest are %0xFF bytes
83 * UBI_IO_BAD_EC_HDR: the erase counter header is corrupted (bad magic or CRC)
84 * UBI_IO_BAD_VID_HDR: the volume identifier header is corrupted (bad magic or
86 * UBI_IO_BITFLIPS: bit-flips were detected and corrected
97 * struct ubi_wl_entry - wear-leveling entry.
98 * @rb: link in the corresponding RB-tree
100 * @pnum: physical eraseblock number
102 * This data structure is used in the WL sub-system. Each physical eraseblock
103 * has a corresponding &struct wl_entry object which may be kept in different
104 * RB-trees. See WL sub-system for details.
106 struct ubi_wl_entry {
113 * struct ubi_ltree_entry - an entry in the lock tree.
114 * @rb: links RB-tree nodes
115 * @vol_id: volume ID of the locked logical eraseblock
116 * @lnum: locked logical eraseblock number
117 * @users: how many tasks are using this logical eraseblock or wait for it
118 * @mutex: read/write mutex to implement read/write access serialization to
119 * the (@vol_id, @lnum) logical eraseblock
121 * This data structure is used in the EBA sub-system to implement per-LEB
122 * locking. When a logical eraseblock is being locked - corresponding
123 * &struct ubi_ltree_entry object is inserted to the lock tree (@ubi->ltree).
124 * See EBA sub-system for details.
126 struct ubi_ltree_entry {
131 struct rw_semaphore mutex;
134 struct ubi_volume_desc;
137 * struct ubi_volume - UBI volume description data structure.
138 * @dev: device object to make use of the the Linux device model
139 * @cdev: character device object to create character device
140 * @ubi: reference to the UBI device description object
142 * @ref_count: volume reference count
143 * @readers: number of users holding this volume in read-only mode
144 * @writers: number of users holding this volume in read-write mode
145 * @exclusive: whether somebody holds this volume in exclusive mode
147 * @reserved_pebs: how many physical eraseblocks are reserved for this volume
148 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
149 * @usable_leb_size: logical eraseblock size without padding
150 * @used_ebs: how many logical eraseblocks in this volume contain data
151 * @last_eb_bytes: how many bytes are stored in the last logical eraseblock
152 * @used_bytes: how many bytes of data this volume contains
153 * @alignment: volume alignment
154 * @data_pad: how many bytes are not used at the end of physical eraseblocks to
155 * satisfy the requested alignment
156 * @name_len: volume name length
159 * @upd_ebs: how many eraseblocks are expected to be updated
160 * @ch_lnum: LEB number which is being changing by the atomic LEB change
162 * @ch_dtype: data persistency type which is being changing by the atomic LEB
164 * @upd_bytes: how many bytes are expected to be received for volume update or
166 * @upd_received: how many bytes were already received for volume update or
168 * @upd_buf: update buffer which is used to collect update data or data for
171 * @eba_tbl: EBA table of this volume (LEB->PEB mapping)
172 * @checked: %1 if this static volume was checked
173 * @corrupted: %1 if the volume is corrupted (static volumes only)
174 * @upd_marker: %1 if the update marker is set for this volume
175 * @updating: %1 if the volume is being updated
176 * @changing_leb: %1 if the atomic LEB change ioctl command is in progress
178 * @gluebi_desc: gluebi UBI volume descriptor
179 * @gluebi_refcount: reference count of the gluebi MTD device
180 * @gluebi_mtd: MTD device description object of the gluebi MTD device
182 * The @corrupted field indicates that the volume's contents is corrupted.
183 * Since UBI protects only static volumes, this field is not relevant to
184 * dynamic volumes - it is user's responsibility to assure their data
187 * The @upd_marker flag indicates that this volume is either being updated at
188 * the moment or is damaged because of an unclean reboot.
193 struct ubi_device *ubi;
205 long long used_bytes;
209 char name[UBI_VOL_NAME_MAX+1];
215 long long upd_received;
219 unsigned int checked:1;
220 unsigned int corrupted:1;
221 unsigned int upd_marker:1;
222 unsigned int updating:1;
223 unsigned int changing_leb:1;
225 #ifdef CONFIG_MTD_UBI_GLUEBI
227 * Gluebi-related stuff may be compiled out.
228 * Note: this should not be built into UBI but should be a separate
229 * ubimtd driver which works on top of UBI and emulates MTD devices.
231 struct ubi_volume_desc *gluebi_desc;
233 struct mtd_info gluebi_mtd;
238 * struct ubi_volume_desc - UBI volume descriptor returned when it is opened.
239 * @vol: reference to the corresponding volume description object
240 * @mode: open mode (%UBI_READONLY, %UBI_READWRITE, or %UBI_EXCLUSIVE)
242 struct ubi_volume_desc {
243 struct ubi_volume *vol;
250 * struct ubi_device - UBI device description structure
251 * @dev: UBI device object to use the the Linux device model
252 * @cdev: character device object to create character device
253 * @ubi_num: UBI device number
254 * @ubi_name: UBI device name
255 * @vol_count: number of volumes in this UBI device
256 * @volumes: volumes of this UBI device
257 * @volumes_lock: protects @volumes, @rsvd_pebs, @avail_pebs, beb_rsvd_pebs,
258 * @beb_rsvd_level, @bad_peb_count, @good_peb_count, @vol_count,
259 * @vol->readers, @vol->writers, @vol->exclusive,
260 * @vol->ref_count, @vol->mapping and @vol->eba_tbl.
261 * @ref_count: count of references on the UBI device
263 * @rsvd_pebs: count of reserved physical eraseblocks
264 * @avail_pebs: count of available physical eraseblocks
265 * @beb_rsvd_pebs: how many physical eraseblocks are reserved for bad PEB
267 * @beb_rsvd_level: normal level of PEBs reserved for bad PEB handling
269 * @autoresize_vol_id: ID of the volume which has to be auto-resized at the end
270 * of UBI ititializetion
271 * @vtbl_slots: how many slots are available in the volume table
272 * @vtbl_size: size of the volume table in bytes
273 * @vtbl: in-RAM volume table copy
274 * @volumes_mutex: protects on-flash volume table and serializes volume
275 * changes, like creation, deletion, update, resize
277 * @max_ec: current highest erase counter value
278 * @mean_ec: current mean erase counter value
280 * @global_sqnum: global sequence number
281 * @ltree_lock: protects the lock tree and @global_sqnum
282 * @ltree: the lock tree
283 * @alc_mutex: serializes "atomic LEB change" operations
285 * @used: RB-tree of used physical eraseblocks
286 * @free: RB-tree of free physical eraseblocks
287 * @scrub: RB-tree of physical eraseblocks which need scrubbing
288 * @prot: protection trees
289 * @prot.pnum: protection tree indexed by physical eraseblock numbers
290 * @prot.aec: protection tree indexed by absolute erase counter value
291 * @wl_lock: protects the @used, @free, @prot, @lookuptbl, @abs_ec, @move_from,
292 * @move_to, @move_to_put @erase_pending, @wl_scheduled, and @works
294 * @move_mutex: serializes eraseblock moves
295 * @wl_scheduled: non-zero if the wear-leveling was scheduled
296 * @lookuptbl: a table to quickly find a &struct ubi_wl_entry object for any
297 * physical eraseblock
298 * @abs_ec: absolute erase counter
299 * @move_from: physical eraseblock from where the data is being moved
300 * @move_to: physical eraseblock where the data is being moved to
301 * @move_to_put: if the "to" PEB was put
302 * @works: list of pending works
303 * @works_count: count of pending works
304 * @bgt_thread: background thread description object
305 * @thread_enabled: if the background thread is enabled
306 * @bgt_name: background thread name
308 * @flash_size: underlying MTD device size (in bytes)
309 * @peb_count: count of physical eraseblocks on the MTD device
310 * @peb_size: physical eraseblock size
311 * @bad_peb_count: count of bad physical eraseblocks
312 * @good_peb_count: count of good physical eraseblocks
313 * @min_io_size: minimal input/output unit size of the underlying MTD device
314 * @hdrs_min_io_size: minimal I/O unit size used for VID and EC headers
315 * @ro_mode: if the UBI device is in read-only mode
316 * @leb_size: logical eraseblock size
317 * @leb_start: starting offset of logical eraseblocks within physical
319 * @ec_hdr_alsize: size of the EC header aligned to @hdrs_min_io_size
320 * @vid_hdr_alsize: size of the VID header aligned to @hdrs_min_io_size
321 * @vid_hdr_offset: starting offset of the volume identifier header (might be
323 * @vid_hdr_aloffset: starting offset of the VID header aligned to
325 * @vid_hdr_shift: contains @vid_hdr_offset - @vid_hdr_aloffset
326 * @bad_allowed: whether the MTD device admits of bad physical eraseblocks or
328 * @mtd: MTD device descriptor
330 * @peb_buf1: a buffer of PEB size used for different purposes
331 * @peb_buf2: another buffer of PEB size used for different purposes
332 * @buf_mutex: proptects @peb_buf1 and @peb_buf2
333 * @dbg_peb_buf: buffer of PEB size used for debugging
334 * @dbg_buf_mutex: proptects @dbg_peb_buf
340 char ubi_name[sizeof(UBI_NAME_STR)+5];
342 struct ubi_volume *volumes[UBI_MAX_VOLUMES+UBI_INT_VOL_COUNT];
343 spinlock_t volumes_lock;
351 int autoresize_vol_id;
354 struct ubi_vtbl_record *vtbl;
355 struct mutex volumes_mutex;
358 /* Note, mean_ec is not updated run-time - should be fixed */
361 /* EBA sub-system's stuff */
362 unsigned long long global_sqnum;
363 spinlock_t ltree_lock;
364 struct rb_root ltree;
365 struct mutex alc_mutex;
367 /* Wear-leveling sub-system's stuff */
370 struct rb_root scrub;
376 struct mutex move_mutex;
377 struct rw_semaphore work_sem;
379 struct ubi_wl_entry **lookuptbl;
380 unsigned long long abs_ec;
381 struct ubi_wl_entry *move_from;
382 struct ubi_wl_entry *move_to;
384 struct list_head works;
386 struct task_struct *bgt_thread;
388 char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
390 /* I/O sub-system's stuff */
391 long long flash_size;
397 int hdrs_min_io_size;
404 int vid_hdr_aloffset;
407 struct mtd_info *mtd;
411 struct mutex buf_mutex;
412 struct mutex ckvol_mutex;
413 #ifdef CONFIG_MTD_UBI_DEBUG
415 struct mutex dbg_buf_mutex;
419 extern struct kmem_cache *ubi_wl_entry_slab;
420 extern struct file_operations ubi_ctrl_cdev_operations;
421 extern struct file_operations ubi_cdev_operations;
422 extern struct file_operations ubi_vol_cdev_operations;
423 extern struct class *ubi_class;
424 extern struct mutex ubi_devices_mutex;
427 int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
428 struct ubi_vtbl_record *vtbl_rec);
429 int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si);
432 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req);
433 int ubi_remove_volume(struct ubi_volume_desc *desc);
434 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs);
435 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol);
436 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol);
439 int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
441 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
442 const void __user *buf, int count);
443 int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
444 const struct ubi_leb_change_req *req);
445 int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
446 const void __user *buf, int count);
449 int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf, int length);
450 int ubi_check_volume(struct ubi_device *ubi, int vol_id);
451 void ubi_calculate_reserved(struct ubi_device *ubi);
454 #ifdef CONFIG_MTD_UBI_GLUEBI
455 int ubi_create_gluebi(struct ubi_device *ubi, struct ubi_volume *vol);
456 int ubi_destroy_gluebi(struct ubi_volume *vol);
457 void ubi_gluebi_updated(struct ubi_volume *vol);
459 #define ubi_create_gluebi(ubi, vol) 0
460 #define ubi_destroy_gluebi(vol) 0
461 #define ubi_gluebi_updated(vol)
465 int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
467 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
468 void *buf, int offset, int len, int check);
469 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
470 const void *buf, int offset, int len, int dtype);
471 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
472 int lnum, const void *buf, int len, int dtype,
474 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
475 int lnum, const void *buf, int len, int dtype);
476 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
477 struct ubi_vid_hdr *vid_hdr);
478 int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
481 int ubi_wl_get_peb(struct ubi_device *ubi, int dtype);
482 int ubi_wl_put_peb(struct ubi_device *ubi, int pnum, int torture);
483 int ubi_wl_flush(struct ubi_device *ubi);
484 int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum);
485 int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si);
486 void ubi_wl_close(struct ubi_device *ubi);
487 int ubi_thread(void *u);
490 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
492 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
494 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture);
495 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum);
496 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum);
497 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
498 struct ubi_ec_hdr *ec_hdr, int verbose);
499 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
500 struct ubi_ec_hdr *ec_hdr);
501 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
502 struct ubi_vid_hdr *vid_hdr, int verbose);
503 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
504 struct ubi_vid_hdr *vid_hdr);
507 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset);
508 int ubi_detach_mtd_dev(int ubi_num, int anyway);
509 struct ubi_device *ubi_get_device(int ubi_num);
510 void ubi_put_device(struct ubi_device *ubi);
511 struct ubi_device *ubi_get_by_major(int major);
512 int ubi_major2num(int major);
515 * ubi_rb_for_each_entry - walk an RB-tree.
516 * @rb: a pointer to type 'struct rb_node' to to use as a loop counter
517 * @pos: a pointer to RB-tree entry type to use as a loop counter
518 * @root: RB-tree's root
519 * @member: the name of the 'struct rb_node' within the RB-tree entry
521 #define ubi_rb_for_each_entry(rb, pos, root, member) \
522 for (rb = rb_first(root), \
523 pos = (rb ? container_of(rb, typeof(*pos), member) : NULL); \
525 rb = rb_next(rb), pos = container_of(rb, typeof(*pos), member))
528 * ubi_zalloc_vid_hdr - allocate a volume identifier header object.
529 * @ubi: UBI device description object
530 * @gfp_flags: GFP flags to allocate with
532 * This function returns a pointer to the newly allocated and zero-filled
533 * volume identifier header object in case of success and %NULL in case of
536 static inline struct ubi_vid_hdr *
537 ubi_zalloc_vid_hdr(const struct ubi_device *ubi, gfp_t gfp_flags)
541 vid_hdr = kzalloc(ubi->vid_hdr_alsize, gfp_flags);
546 * VID headers may be stored at un-aligned flash offsets, so we shift
549 return vid_hdr + ubi->vid_hdr_shift;
553 * ubi_free_vid_hdr - free a volume identifier header object.
554 * @ubi: UBI device description object
555 * @vid_hdr: the object to free
557 static inline void ubi_free_vid_hdr(const struct ubi_device *ubi,
558 struct ubi_vid_hdr *vid_hdr)
565 kfree(p - ubi->vid_hdr_shift);
569 * This function is equivalent to 'ubi_io_read()', but @offset is relative to
570 * the beginning of the logical eraseblock, not to the beginning of the
571 * physical eraseblock.
573 static inline int ubi_io_read_data(const struct ubi_device *ubi, void *buf,
574 int pnum, int offset, int len)
576 ubi_assert(offset >= 0);
577 return ubi_io_read(ubi, buf, pnum, offset + ubi->leb_start, len);
581 * This function is equivalent to 'ubi_io_write()', but @offset is relative to
582 * the beginning of the logical eraseblock, not to the beginning of the
583 * physical eraseblock.
585 static inline int ubi_io_write_data(struct ubi_device *ubi, const void *buf,
586 int pnum, int offset, int len)
588 ubi_assert(offset >= 0);
589 return ubi_io_write(ubi, buf, pnum, offset + ubi->leb_start, len);
593 * ubi_ro_mode - switch to read-only mode.
594 * @ubi: UBI device description object
596 static inline void ubi_ro_mode(struct ubi_device *ubi)
600 ubi_warn("switch to read-only mode");
605 * vol_id2idx - get table index by volume ID.
606 * @ubi: UBI device description object
609 static inline int vol_id2idx(const struct ubi_device *ubi, int vol_id)
611 if (vol_id >= UBI_INTERNAL_VOL_START)
612 return vol_id - UBI_INTERNAL_VOL_START + ubi->vtbl_slots;
618 * idx2vol_id - get volume ID by table index.
619 * @ubi: UBI device description object
622 static inline int idx2vol_id(const struct ubi_device *ubi, int idx)
624 if (idx >= ubi->vtbl_slots)
625 return idx - ubi->vtbl_slots + UBI_INTERNAL_VOL_START;
630 #endif /* !__UBI_UBI_H__ */