2 * Copyright (c) International Business Machines Corp., 2006
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
12 * the GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 * Author: Artem Bityutskiy (Битюцкий Артём)
22 * The UBI Eraseblock Association (EBA) unit.
24 * This unit is responsible for I/O to/from logical eraseblock.
26 * Although in this implementation the EBA table is fully kept and managed in
27 * RAM, which assumes poor scalability, it might be (partially) maintained on
28 * flash in future implementations.
30 * The EBA unit implements per-logical eraseblock locking. Before accessing a
31 * logical eraseblock it is locked for reading or writing. The per-logical
32 * eraseblock locking is implemented by means of the lock tree. The lock tree
33 * is an RB-tree which refers all the currently locked logical eraseblocks. The
34 * lock tree elements are &struct ubi_ltree_entry objects. They are indexed by
35 * (@vol_id, @lnum) pairs.
37 * EBA also maintains the global sequence counter which is incremented each
38 * time a logical eraseblock is mapped to a physical eraseblock and it is
39 * stored in the volume identifier header. This means that each VID header has
40 * a unique sequence number. The sequence number is only increased an we assume
41 * 64 bits is enough to never overflow.
44 #include <linux/slab.h>
45 #include <linux/crc32.h>
46 #include <linux/err.h>
49 /* Number of physical eraseblocks reserved for atomic LEB change operation */
50 #define EBA_RESERVED_PEBS 1
53 * next_sqnum - get next sequence number.
54 * @ubi: UBI device description object
56 * This function returns next sequence number to use, which is just the current
57 * global sequence counter value. It also increases the global sequence
60 static unsigned long long next_sqnum(struct ubi_device *ubi)
62 unsigned long long sqnum;
64 spin_lock(&ubi->ltree_lock);
65 sqnum = ubi->global_sqnum++;
66 spin_unlock(&ubi->ltree_lock);
72 * ubi_get_compat - get compatibility flags of a volume.
73 * @ubi: UBI device description object
76 * This function returns compatibility flags for an internal volume. User
77 * volumes have no compatibility flags, so %0 is returned.
79 static int ubi_get_compat(const struct ubi_device *ubi, int vol_id)
81 if (vol_id == UBI_LAYOUT_VOL_ID)
82 return UBI_LAYOUT_VOLUME_COMPAT;
87 * ltree_lookup - look up the lock tree.
88 * @ubi: UBI device description object
90 * @lnum: logical eraseblock number
92 * This function returns a pointer to the corresponding &struct ubi_ltree_entry
93 * object if the logical eraseblock is locked and %NULL if it is not.
94 * @ubi->ltree_lock has to be locked.
96 static struct ubi_ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id,
101 p = ubi->ltree.rb_node;
103 struct ubi_ltree_entry *le;
105 le = rb_entry(p, struct ubi_ltree_entry, rb);
107 if (vol_id < le->vol_id)
109 else if (vol_id > le->vol_id)
114 else if (lnum > le->lnum)
125 * ltree_add_entry - add new entry to the lock tree.
126 * @ubi: UBI device description object
128 * @lnum: logical eraseblock number
130 * This function adds new entry for logical eraseblock (@vol_id, @lnum) to the
131 * lock tree. If such entry is already there, its usage counter is increased.
132 * Returns pointer to the lock tree entry or %-ENOMEM if memory allocation
135 static struct ubi_ltree_entry *ltree_add_entry(struct ubi_device *ubi,
136 int vol_id, int lnum)
138 struct ubi_ltree_entry *le, *le1, *le_free;
140 le = kmem_cache_alloc(ubi_ltree_slab, GFP_NOFS);
142 return ERR_PTR(-ENOMEM);
147 spin_lock(&ubi->ltree_lock);
148 le1 = ltree_lookup(ubi, vol_id, lnum);
152 * This logical eraseblock is already locked. The newly
153 * allocated lock entry is not needed.
158 struct rb_node **p, *parent = NULL;
161 * No lock entry, add the newly allocated one to the
162 * @ubi->ltree RB-tree.
166 p = &ubi->ltree.rb_node;
169 le1 = rb_entry(parent, struct ubi_ltree_entry, rb);
171 if (vol_id < le1->vol_id)
173 else if (vol_id > le1->vol_id)
176 ubi_assert(lnum != le1->lnum);
177 if (lnum < le1->lnum)
184 rb_link_node(&le->rb, parent, p);
185 rb_insert_color(&le->rb, &ubi->ltree);
188 spin_unlock(&ubi->ltree_lock);
191 kmem_cache_free(ubi_ltree_slab, le_free);
197 * leb_read_lock - lock logical eraseblock for reading.
198 * @ubi: UBI device description object
200 * @lnum: logical eraseblock number
202 * This function locks a logical eraseblock for reading. Returns zero in case
203 * of success and a negative error code in case of failure.
205 static int leb_read_lock(struct ubi_device *ubi, int vol_id, int lnum)
207 struct ubi_ltree_entry *le;
209 le = ltree_add_entry(ubi, vol_id, lnum);
212 down_read(&le->mutex);
217 * leb_read_unlock - unlock logical eraseblock.
218 * @ubi: UBI device description object
220 * @lnum: logical eraseblock number
222 static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum)
225 struct ubi_ltree_entry *le;
227 spin_lock(&ubi->ltree_lock);
228 le = ltree_lookup(ubi, vol_id, lnum);
230 ubi_assert(le->users >= 0);
231 if (le->users == 0) {
232 rb_erase(&le->rb, &ubi->ltree);
235 spin_unlock(&ubi->ltree_lock);
239 kmem_cache_free(ubi_ltree_slab, le);
243 * leb_write_lock - lock logical eraseblock for writing.
244 * @ubi: UBI device description object
246 * @lnum: logical eraseblock number
248 * This function locks a logical eraseblock for writing. Returns zero in case
249 * of success and a negative error code in case of failure.
251 static int leb_write_lock(struct ubi_device *ubi, int vol_id, int lnum)
253 struct ubi_ltree_entry *le;
255 le = ltree_add_entry(ubi, vol_id, lnum);
258 down_write(&le->mutex);
263 * leb_write_unlock - unlock logical eraseblock.
264 * @ubi: UBI device description object
266 * @lnum: logical eraseblock number
268 static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum)
271 struct ubi_ltree_entry *le;
273 spin_lock(&ubi->ltree_lock);
274 le = ltree_lookup(ubi, vol_id, lnum);
276 ubi_assert(le->users >= 0);
277 if (le->users == 0) {
278 rb_erase(&le->rb, &ubi->ltree);
282 spin_unlock(&ubi->ltree_lock);
284 up_write(&le->mutex);
286 kmem_cache_free(ubi_ltree_slab, le);
290 * ubi_eba_unmap_leb - un-map logical eraseblock.
291 * @ubi: UBI device description object
293 * @lnum: logical eraseblock number
295 * This function un-maps logical eraseblock @lnum and schedules corresponding
296 * physical eraseblock for erasure. Returns zero in case of success and a
297 * negative error code in case of failure.
299 int ubi_eba_unmap_leb(struct ubi_device *ubi, int vol_id, int lnum)
301 int idx = vol_id2idx(ubi, vol_id), err, pnum;
302 struct ubi_volume *vol = ubi->volumes[idx];
307 err = leb_write_lock(ubi, vol_id, lnum);
311 pnum = vol->eba_tbl[lnum];
313 /* This logical eraseblock is already unmapped */
316 dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum);
318 vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED;
319 err = ubi_wl_put_peb(ubi, pnum, 0);
322 leb_write_unlock(ubi, vol_id, lnum);
327 * ubi_eba_read_leb - read data.
328 * @ubi: UBI device description object
330 * @lnum: logical eraseblock number
331 * @buf: buffer to store the read data
332 * @offset: offset from where to read
333 * @len: how many bytes to read
334 * @check: data CRC check flag
336 * If the logical eraseblock @lnum is unmapped, @buf is filled with 0xFF
337 * bytes. The @check flag only makes sense for static volumes and forces
338 * eraseblock data CRC checking.
340 * In case of success this function returns zero. In case of a static volume,
341 * if data CRC mismatches - %-EBADMSG is returned. %-EBADMSG may also be
342 * returned for any volume type if an ECC error was detected by the MTD device
343 * driver. Other negative error cored may be returned in case of other errors.
345 int ubi_eba_read_leb(struct ubi_device *ubi, int vol_id, int lnum, void *buf,
346 int offset, int len, int check)
348 int err, pnum, scrub = 0, idx = vol_id2idx(ubi, vol_id);
349 struct ubi_vid_hdr *vid_hdr;
350 struct ubi_volume *vol = ubi->volumes[idx];
351 uint32_t uninitialized_var(crc);
353 err = leb_read_lock(ubi, vol_id, lnum);
357 pnum = vol->eba_tbl[lnum];
360 * The logical eraseblock is not mapped, fill the whole buffer
361 * with 0xFF bytes. The exception is static volumes for which
362 * it is an error to read unmapped logical eraseblocks.
364 dbg_eba("read %d bytes from offset %d of LEB %d:%d (unmapped)",
365 len, offset, vol_id, lnum);
366 leb_read_unlock(ubi, vol_id, lnum);
367 ubi_assert(vol->vol_type != UBI_STATIC_VOLUME);
368 memset(buf, 0xFF, len);
372 dbg_eba("read %d bytes from offset %d of LEB %d:%d, PEB %d",
373 len, offset, vol_id, lnum, pnum);
375 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
380 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
386 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
387 if (err && err != UBI_IO_BITFLIPS) {
390 * The header is either absent or corrupted.
391 * The former case means there is a bug -
392 * switch to read-only mode just in case.
393 * The latter case means a real corruption - we
394 * may try to recover data. FIXME: but this is
397 if (err == UBI_IO_BAD_VID_HDR) {
398 ubi_warn("bad VID header at PEB %d, LEB"
399 "%d:%d", pnum, vol_id, lnum);
405 } else if (err == UBI_IO_BITFLIPS)
408 ubi_assert(lnum < be32_to_cpu(vid_hdr->used_ebs));
409 ubi_assert(len == be32_to_cpu(vid_hdr->data_size));
411 crc = be32_to_cpu(vid_hdr->data_crc);
412 ubi_free_vid_hdr(ubi, vid_hdr);
415 err = ubi_io_read_data(ubi, buf, pnum, offset, len);
417 if (err == UBI_IO_BITFLIPS) {
420 } else if (err == -EBADMSG) {
421 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
425 ubi_msg("force data checking");
434 uint32_t crc1 = crc32(UBI_CRC32_INIT, buf, len);
436 ubi_warn("CRC error: calculated %#08x, must be %#08x",
444 err = ubi_wl_scrub_peb(ubi, pnum);
446 leb_read_unlock(ubi, vol_id, lnum);
450 ubi_free_vid_hdr(ubi, vid_hdr);
452 leb_read_unlock(ubi, vol_id, lnum);
457 * recover_peb - recover from write failure.
458 * @ubi: UBI device description object
459 * @pnum: the physical eraseblock to recover
461 * @lnum: logical eraseblock number
462 * @buf: data which was not written because of the write failure
463 * @offset: offset of the failed write
464 * @len: how many bytes should have been written
466 * This function is called in case of a write failure and moves all good data
467 * from the potentially bad physical eraseblock to a good physical eraseblock.
468 * This function also writes the data which was not written due to the failure.
469 * Returns new physical eraseblock number in case of success, and a negative
470 * error code in case of failure.
472 static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum,
473 const void *buf, int offset, int len)
475 int err, idx = vol_id2idx(ubi, vol_id), new_pnum, data_size, tries = 0;
476 struct ubi_volume *vol = ubi->volumes[idx];
477 struct ubi_vid_hdr *vid_hdr;
479 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
484 mutex_lock(&ubi->buf_mutex);
487 new_pnum = ubi_wl_get_peb(ubi, UBI_UNKNOWN);
489 mutex_unlock(&ubi->buf_mutex);
490 ubi_free_vid_hdr(ubi, vid_hdr);
494 ubi_msg("recover PEB %d, move data to PEB %d", pnum, new_pnum);
496 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
497 if (err && err != UBI_IO_BITFLIPS) {
503 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
504 err = ubi_io_write_vid_hdr(ubi, new_pnum, vid_hdr);
508 data_size = offset + len;
509 memset(ubi->peb_buf1 + offset, 0xFF, len);
511 /* Read everything before the area where the write failure happened */
513 err = ubi_io_read_data(ubi, ubi->peb_buf1, pnum, 0, offset);
514 if (err && err != UBI_IO_BITFLIPS)
518 memcpy(ubi->peb_buf1 + offset, buf, len);
520 err = ubi_io_write_data(ubi, ubi->peb_buf1, new_pnum, 0, data_size);
524 mutex_unlock(&ubi->buf_mutex);
525 ubi_free_vid_hdr(ubi, vid_hdr);
527 vol->eba_tbl[lnum] = new_pnum;
528 ubi_wl_put_peb(ubi, pnum, 1);
530 ubi_msg("data was successfully recovered");
534 mutex_unlock(&ubi->buf_mutex);
535 ubi_wl_put_peb(ubi, new_pnum, 1);
536 ubi_free_vid_hdr(ubi, vid_hdr);
541 * Bad luck? This physical eraseblock is bad too? Crud. Let's try to
544 ubi_warn("failed to write to PEB %d", new_pnum);
545 ubi_wl_put_peb(ubi, new_pnum, 1);
546 if (++tries > UBI_IO_RETRIES) {
547 mutex_unlock(&ubi->buf_mutex);
548 ubi_free_vid_hdr(ubi, vid_hdr);
551 ubi_msg("try again");
556 * ubi_eba_write_leb - write data to dynamic volume.
557 * @ubi: UBI device description object
559 * @lnum: logical eraseblock number
560 * @buf: the data to write
561 * @offset: offset within the logical eraseblock where to write
562 * @len: how many bytes to write
565 * This function writes data to logical eraseblock @lnum of a dynamic volume
566 * @vol_id. Returns zero in case of success and a negative error code in case
567 * of failure. In case of error, it is possible that something was still
568 * written to the flash media, but may be some garbage.
570 int ubi_eba_write_leb(struct ubi_device *ubi, int vol_id, int lnum,
571 const void *buf, int offset, int len, int dtype)
573 int idx = vol_id2idx(ubi, vol_id), err, pnum, tries = 0;
574 struct ubi_volume *vol = ubi->volumes[idx];
575 struct ubi_vid_hdr *vid_hdr;
580 err = leb_write_lock(ubi, vol_id, lnum);
584 pnum = vol->eba_tbl[lnum];
586 dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d",
587 len, offset, vol_id, lnum, pnum);
589 err = ubi_io_write_data(ubi, buf, pnum, offset, len);
591 ubi_warn("failed to write data to PEB %d", pnum);
592 if (err == -EIO && ubi->bad_allowed)
593 err = recover_peb(ubi, pnum, vol_id, lnum, buf, offset, len);
597 leb_write_unlock(ubi, vol_id, lnum);
602 * The logical eraseblock is not mapped. We have to get a free physical
603 * eraseblock and write the volume identifier header there first.
605 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
607 leb_write_unlock(ubi, vol_id, lnum);
611 vid_hdr->vol_type = UBI_VID_DYNAMIC;
612 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
613 vid_hdr->vol_id = cpu_to_be32(vol_id);
614 vid_hdr->lnum = cpu_to_be32(lnum);
615 vid_hdr->compat = ubi_get_compat(ubi, vol_id);
616 vid_hdr->data_pad = cpu_to_be32(vol->data_pad);
619 pnum = ubi_wl_get_peb(ubi, dtype);
621 ubi_free_vid_hdr(ubi, vid_hdr);
622 leb_write_unlock(ubi, vol_id, lnum);
626 dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d",
627 len, offset, vol_id, lnum, pnum);
629 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
631 ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
637 err = ubi_io_write_data(ubi, buf, pnum, offset, len);
639 ubi_warn("failed to write %d bytes at offset %d of "
640 "LEB %d:%d, PEB %d", len, offset, vol_id,
646 vol->eba_tbl[lnum] = pnum;
648 leb_write_unlock(ubi, vol_id, lnum);
649 ubi_free_vid_hdr(ubi, vid_hdr);
653 if (err != -EIO || !ubi->bad_allowed) {
655 leb_write_unlock(ubi, vol_id, lnum);
656 ubi_free_vid_hdr(ubi, vid_hdr);
661 * Fortunately, this is the first write operation to this physical
662 * eraseblock, so just put it and request a new one. We assume that if
663 * this physical eraseblock went bad, the erase code will handle that.
665 err = ubi_wl_put_peb(ubi, pnum, 1);
666 if (err || ++tries > UBI_IO_RETRIES) {
668 leb_write_unlock(ubi, vol_id, lnum);
669 ubi_free_vid_hdr(ubi, vid_hdr);
673 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
674 ubi_msg("try another PEB");
679 * ubi_eba_write_leb_st - write data to static volume.
680 * @ubi: UBI device description object
682 * @lnum: logical eraseblock number
683 * @buf: data to write
684 * @len: how many bytes to write
686 * @used_ebs: how many logical eraseblocks will this volume contain
688 * This function writes data to logical eraseblock @lnum of static volume
689 * @vol_id. The @used_ebs argument should contain total number of logical
690 * eraseblock in this static volume.
692 * When writing to the last logical eraseblock, the @len argument doesn't have
693 * to be aligned to the minimal I/O unit size. Instead, it has to be equivalent
694 * to the real data size, although the @buf buffer has to contain the
695 * alignment. In all other cases, @len has to be aligned.
697 * It is prohibited to write more then once to logical eraseblocks of static
698 * volumes. This function returns zero in case of success and a negative error
699 * code in case of failure.
701 int ubi_eba_write_leb_st(struct ubi_device *ubi, int vol_id, int lnum,
702 const void *buf, int len, int dtype, int used_ebs)
704 int err, pnum, tries = 0, data_size = len;
705 int idx = vol_id2idx(ubi, vol_id);
706 struct ubi_volume *vol = ubi->volumes[idx];
707 struct ubi_vid_hdr *vid_hdr;
713 if (lnum == used_ebs - 1)
714 /* If this is the last LEB @len may be unaligned */
715 len = ALIGN(data_size, ubi->min_io_size);
717 ubi_assert(len % ubi->min_io_size == 0);
719 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
723 err = leb_write_lock(ubi, vol_id, lnum);
725 ubi_free_vid_hdr(ubi, vid_hdr);
729 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
730 vid_hdr->vol_id = cpu_to_be32(vol_id);
731 vid_hdr->lnum = cpu_to_be32(lnum);
732 vid_hdr->compat = ubi_get_compat(ubi, vol_id);
733 vid_hdr->data_pad = cpu_to_be32(vol->data_pad);
735 crc = crc32(UBI_CRC32_INIT, buf, data_size);
736 vid_hdr->vol_type = UBI_VID_STATIC;
737 vid_hdr->data_size = cpu_to_be32(data_size);
738 vid_hdr->used_ebs = cpu_to_be32(used_ebs);
739 vid_hdr->data_crc = cpu_to_be32(crc);
742 pnum = ubi_wl_get_peb(ubi, dtype);
744 ubi_free_vid_hdr(ubi, vid_hdr);
745 leb_write_unlock(ubi, vol_id, lnum);
749 dbg_eba("write VID hdr and %d bytes at LEB %d:%d, PEB %d, used_ebs %d",
750 len, vol_id, lnum, pnum, used_ebs);
752 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
754 ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
759 err = ubi_io_write_data(ubi, buf, pnum, 0, len);
761 ubi_warn("failed to write %d bytes of data to PEB %d",
766 ubi_assert(vol->eba_tbl[lnum] < 0);
767 vol->eba_tbl[lnum] = pnum;
769 leb_write_unlock(ubi, vol_id, lnum);
770 ubi_free_vid_hdr(ubi, vid_hdr);
774 if (err != -EIO || !ubi->bad_allowed) {
776 * This flash device does not admit of bad eraseblocks or
777 * something nasty and unexpected happened. Switch to read-only
781 leb_write_unlock(ubi, vol_id, lnum);
782 ubi_free_vid_hdr(ubi, vid_hdr);
786 err = ubi_wl_put_peb(ubi, pnum, 1);
787 if (err || ++tries > UBI_IO_RETRIES) {
789 leb_write_unlock(ubi, vol_id, lnum);
790 ubi_free_vid_hdr(ubi, vid_hdr);
794 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
795 ubi_msg("try another PEB");
800 * ubi_eba_atomic_leb_change - change logical eraseblock atomically.
801 * @ubi: UBI device description object
803 * @lnum: logical eraseblock number
804 * @buf: data to write
805 * @len: how many bytes to write
808 * This function changes the contents of a logical eraseblock atomically. @buf
809 * has to contain new logical eraseblock data, and @len - the length of the
810 * data, which has to be aligned. This function guarantees that in case of an
811 * unclean reboot the old contents is preserved. Returns zero in case of
812 * success and a negative error code in case of failure.
814 * UBI reserves one LEB for the "atomic LEB change" operation, so only one
815 * LEB change may be done at a time. This is ensured by @ubi->alc_mutex.
817 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, int vol_id, int lnum,
818 const void *buf, int len, int dtype)
820 int err, pnum, tries = 0, idx = vol_id2idx(ubi, vol_id);
821 struct ubi_volume *vol = ubi->volumes[idx];
822 struct ubi_vid_hdr *vid_hdr;
828 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
832 mutex_lock(&ubi->alc_mutex);
833 err = leb_write_lock(ubi, vol_id, lnum);
837 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
838 vid_hdr->vol_id = cpu_to_be32(vol_id);
839 vid_hdr->lnum = cpu_to_be32(lnum);
840 vid_hdr->compat = ubi_get_compat(ubi, vol_id);
841 vid_hdr->data_pad = cpu_to_be32(vol->data_pad);
843 crc = crc32(UBI_CRC32_INIT, buf, len);
844 vid_hdr->vol_type = UBI_VID_DYNAMIC;
845 vid_hdr->data_size = cpu_to_be32(len);
846 vid_hdr->copy_flag = 1;
847 vid_hdr->data_crc = cpu_to_be32(crc);
850 pnum = ubi_wl_get_peb(ubi, dtype);
856 dbg_eba("change LEB %d:%d, PEB %d, write VID hdr to PEB %d",
857 vol_id, lnum, vol->eba_tbl[lnum], pnum);
859 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
861 ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
866 err = ubi_io_write_data(ubi, buf, pnum, 0, len);
868 ubi_warn("failed to write %d bytes of data to PEB %d",
873 if (vol->eba_tbl[lnum] >= 0) {
874 err = ubi_wl_put_peb(ubi, vol->eba_tbl[lnum], 1);
879 vol->eba_tbl[lnum] = pnum;
882 leb_write_unlock(ubi, vol_id, lnum);
884 mutex_unlock(&ubi->alc_mutex);
885 ubi_free_vid_hdr(ubi, vid_hdr);
889 if (err != -EIO || !ubi->bad_allowed) {
891 * This flash device does not admit of bad eraseblocks or
892 * something nasty and unexpected happened. Switch to read-only
899 err = ubi_wl_put_peb(ubi, pnum, 1);
900 if (err || ++tries > UBI_IO_RETRIES) {
905 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
906 ubi_msg("try another PEB");
911 * ubi_eba_copy_leb - copy logical eraseblock.
912 * @ubi: UBI device description object
913 * @from: physical eraseblock number from where to copy
914 * @to: physical eraseblock number where to copy
915 * @vid_hdr: VID header of the @from physical eraseblock
917 * This function copies logical eraseblock from physical eraseblock @from to
918 * physical eraseblock @to. The @vid_hdr buffer may be changed by this
919 * function. Returns zero in case of success, %UBI_IO_BITFLIPS if the operation
920 * was canceled because bit-flips were detected at the target PEB, and a
921 * negative error code in case of failure.
923 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
924 struct ubi_vid_hdr *vid_hdr)
926 int err, vol_id, lnum, data_size, aldata_size, pnum, idx;
927 struct ubi_volume *vol;
930 vol_id = be32_to_cpu(vid_hdr->vol_id);
931 lnum = be32_to_cpu(vid_hdr->lnum);
933 dbg_eba("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to);
935 if (vid_hdr->vol_type == UBI_VID_STATIC) {
936 data_size = be32_to_cpu(vid_hdr->data_size);
937 aldata_size = ALIGN(data_size, ubi->min_io_size);
939 data_size = aldata_size =
940 ubi->leb_size - be32_to_cpu(vid_hdr->data_pad);
943 * We do not want anybody to write to this logical eraseblock while we
944 * are moving it, so we lock it.
946 err = leb_write_lock(ubi, vol_id, lnum);
950 mutex_lock(&ubi->buf_mutex);
953 * But the logical eraseblock might have been put by this time.
954 * Cancel if it is true.
956 idx = vol_id2idx(ubi, vol_id);
959 * We may race with volume deletion/re-size, so we have to hold
960 * @ubi->volumes_lock.
962 spin_lock(&ubi->volumes_lock);
963 vol = ubi->volumes[idx];
965 dbg_eba("volume %d was removed meanwhile", vol_id);
966 spin_unlock(&ubi->volumes_lock);
970 pnum = vol->eba_tbl[lnum];
972 dbg_eba("LEB %d:%d is no longer mapped to PEB %d, mapped to "
973 "PEB %d, cancel", vol_id, lnum, from, pnum);
974 spin_unlock(&ubi->volumes_lock);
977 spin_unlock(&ubi->volumes_lock);
979 /* OK, now the LEB is locked and we can safely start moving it */
981 dbg_eba("read %d bytes of data", aldata_size);
982 err = ubi_io_read_data(ubi, ubi->peb_buf1, from, 0, aldata_size);
983 if (err && err != UBI_IO_BITFLIPS) {
984 ubi_warn("error %d while reading data from PEB %d",
990 * Now we have got to calculate how much data we have to to copy. In
991 * case of a static volume it is fairly easy - the VID header contains
992 * the data size. In case of a dynamic volume it is more difficult - we
993 * have to read the contents, cut 0xFF bytes from the end and copy only
994 * the first part. We must do this to avoid writing 0xFF bytes as it
995 * may have some side-effects. And not only this. It is important not
996 * to include those 0xFFs to CRC because later the they may be filled
999 if (vid_hdr->vol_type == UBI_VID_DYNAMIC)
1000 aldata_size = data_size =
1001 ubi_calc_data_len(ubi, ubi->peb_buf1, data_size);
1004 crc = crc32(UBI_CRC32_INIT, ubi->peb_buf1, data_size);
1008 * It may turn out to me that the whole @from physical eraseblock
1009 * contains only 0xFF bytes. Then we have to only write the VID header
1010 * and do not write any data. This also means we should not set
1011 * @vid_hdr->copy_flag, @vid_hdr->data_size, and @vid_hdr->data_crc.
1013 if (data_size > 0) {
1014 vid_hdr->copy_flag = 1;
1015 vid_hdr->data_size = cpu_to_be32(data_size);
1016 vid_hdr->data_crc = cpu_to_be32(crc);
1018 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
1020 err = ubi_io_write_vid_hdr(ubi, to, vid_hdr);
1026 /* Read the VID header back and check if it was written correctly */
1027 err = ubi_io_read_vid_hdr(ubi, to, vid_hdr, 1);
1029 if (err != UBI_IO_BITFLIPS)
1030 ubi_warn("cannot read VID header back from PEB %d", to);
1034 if (data_size > 0) {
1035 err = ubi_io_write_data(ubi, ubi->peb_buf1, to, 0, aldata_size);
1042 * We've written the data and are going to read it back to make
1043 * sure it was written correctly.
1046 err = ubi_io_read_data(ubi, ubi->peb_buf2, to, 0, aldata_size);
1048 if (err != UBI_IO_BITFLIPS)
1049 ubi_warn("cannot read data back from PEB %d",
1056 if (memcmp(ubi->peb_buf1, ubi->peb_buf2, aldata_size)) {
1057 ubi_warn("read data back from PEB %d - it is different",
1063 ubi_assert(vol->eba_tbl[lnum] == from);
1064 vol->eba_tbl[lnum] = to;
1067 mutex_unlock(&ubi->buf_mutex);
1068 leb_write_unlock(ubi, vol_id, lnum);
1073 * ubi_eba_init_scan - initialize the EBA unit using scanning information.
1074 * @ubi: UBI device description object
1075 * @si: scanning information
1077 * This function returns zero in case of success and a negative error code in
1080 int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
1082 int i, j, err, num_volumes;
1083 struct ubi_scan_volume *sv;
1084 struct ubi_volume *vol;
1085 struct ubi_scan_leb *seb;
1088 dbg_eba("initialize EBA unit");
1090 spin_lock_init(&ubi->ltree_lock);
1091 mutex_init(&ubi->alc_mutex);
1092 ubi->ltree = RB_ROOT;
1094 ubi->global_sqnum = si->max_sqnum + 1;
1095 num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
1097 for (i = 0; i < num_volumes; i++) {
1098 vol = ubi->volumes[i];
1104 vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int),
1106 if (!vol->eba_tbl) {
1111 for (j = 0; j < vol->reserved_pebs; j++)
1112 vol->eba_tbl[j] = UBI_LEB_UNMAPPED;
1114 sv = ubi_scan_find_sv(si, idx2vol_id(ubi, i));
1118 ubi_rb_for_each_entry(rb, seb, &sv->root, u.rb) {
1119 if (seb->lnum >= vol->reserved_pebs)
1121 * This may happen in case of an unclean reboot
1124 ubi_scan_move_to_list(sv, seb, &si->erase);
1125 vol->eba_tbl[seb->lnum] = seb->pnum;
1129 if (ubi->avail_pebs < EBA_RESERVED_PEBS) {
1130 ubi_err("no enough physical eraseblocks (%d, need %d)",
1131 ubi->avail_pebs, EBA_RESERVED_PEBS);
1135 ubi->avail_pebs -= EBA_RESERVED_PEBS;
1136 ubi->rsvd_pebs += EBA_RESERVED_PEBS;
1138 if (ubi->bad_allowed) {
1139 ubi_calculate_reserved(ubi);
1141 if (ubi->avail_pebs < ubi->beb_rsvd_level) {
1142 /* No enough free physical eraseblocks */
1143 ubi->beb_rsvd_pebs = ubi->avail_pebs;
1144 ubi_warn("cannot reserve enough PEBs for bad PEB "
1145 "handling, reserved %d, need %d",
1146 ubi->beb_rsvd_pebs, ubi->beb_rsvd_level);
1148 ubi->beb_rsvd_pebs = ubi->beb_rsvd_level;
1150 ubi->avail_pebs -= ubi->beb_rsvd_pebs;
1151 ubi->rsvd_pebs += ubi->beb_rsvd_pebs;
1154 dbg_eba("EBA unit is initialized");
1158 for (i = 0; i < num_volumes; i++) {
1159 if (!ubi->volumes[i])
1161 kfree(ubi->volumes[i]->eba_tbl);
1167 * ubi_eba_close - close EBA unit.
1168 * @ubi: UBI device description object
1170 void ubi_eba_close(const struct ubi_device *ubi)
1172 int i, num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
1174 dbg_eba("close EBA unit");
1176 for (i = 0; i < num_volumes; i++) {
1177 if (!ubi->volumes[i])
1179 kfree(ubi->volumes[i]->eba_tbl);