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
292 * @vol: volume 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, struct ubi_volume *vol,
302 int err, pnum, vol_id = vol->vol_id;
304 ubi_assert(vol->ref_count > 0);
309 err = leb_write_lock(ubi, vol_id, lnum);
313 pnum = vol->eba_tbl[lnum];
315 /* This logical eraseblock is already unmapped */
318 dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum);
320 vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED;
321 err = ubi_wl_put_peb(ubi, pnum, 0);
324 leb_write_unlock(ubi, vol_id, lnum);
329 * ubi_eba_read_leb - read data.
330 * @ubi: UBI device description object
331 * @vol: volume description object
332 * @lnum: logical eraseblock number
333 * @buf: buffer to store the read data
334 * @offset: offset from where to read
335 * @len: how many bytes to read
336 * @check: data CRC check flag
338 * If the logical eraseblock @lnum is unmapped, @buf is filled with 0xFF
339 * bytes. The @check flag only makes sense for static volumes and forces
340 * eraseblock data CRC checking.
342 * In case of success this function returns zero. In case of a static volume,
343 * if data CRC mismatches - %-EBADMSG is returned. %-EBADMSG may also be
344 * returned for any volume type if an ECC error was detected by the MTD device
345 * driver. Other negative error cored may be returned in case of other errors.
347 int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
348 void *buf, int offset, int len, int check)
350 int err, pnum, scrub = 0, vol_id = vol->vol_id;
351 struct ubi_vid_hdr *vid_hdr;
352 uint32_t uninitialized_var(crc);
354 ubi_assert(vol->ref_count > 0);
356 err = leb_read_lock(ubi, vol_id, lnum);
360 pnum = vol->eba_tbl[lnum];
363 * The logical eraseblock is not mapped, fill the whole buffer
364 * with 0xFF bytes. The exception is static volumes for which
365 * it is an error to read unmapped logical eraseblocks.
367 dbg_eba("read %d bytes from offset %d of LEB %d:%d (unmapped)",
368 len, offset, vol_id, lnum);
369 leb_read_unlock(ubi, vol_id, lnum);
370 ubi_assert(vol->vol_type != UBI_STATIC_VOLUME);
371 memset(buf, 0xFF, len);
375 dbg_eba("read %d bytes from offset %d of LEB %d:%d, PEB %d",
376 len, offset, vol_id, lnum, pnum);
378 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
383 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
389 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
390 if (err && err != UBI_IO_BITFLIPS) {
393 * The header is either absent or corrupted.
394 * The former case means there is a bug -
395 * switch to read-only mode just in case.
396 * The latter case means a real corruption - we
397 * may try to recover data. FIXME: but this is
400 if (err == UBI_IO_BAD_VID_HDR) {
401 ubi_warn("bad VID header at PEB %d, LEB"
402 "%d:%d", pnum, vol_id, lnum);
408 } else if (err == UBI_IO_BITFLIPS)
411 ubi_assert(lnum < be32_to_cpu(vid_hdr->used_ebs));
412 ubi_assert(len == be32_to_cpu(vid_hdr->data_size));
414 crc = be32_to_cpu(vid_hdr->data_crc);
415 ubi_free_vid_hdr(ubi, vid_hdr);
418 err = ubi_io_read_data(ubi, buf, pnum, offset, len);
420 if (err == UBI_IO_BITFLIPS) {
423 } else if (err == -EBADMSG) {
424 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
428 ubi_msg("force data checking");
437 uint32_t crc1 = crc32(UBI_CRC32_INIT, buf, len);
439 ubi_warn("CRC error: calculated %#08x, must be %#08x",
447 err = ubi_wl_scrub_peb(ubi, pnum);
449 leb_read_unlock(ubi, vol_id, lnum);
453 ubi_free_vid_hdr(ubi, vid_hdr);
455 leb_read_unlock(ubi, vol_id, lnum);
460 * recover_peb - recover from write failure.
461 * @ubi: UBI device description object
462 * @pnum: the physical eraseblock to recover
464 * @lnum: logical eraseblock number
465 * @buf: data which was not written because of the write failure
466 * @offset: offset of the failed write
467 * @len: how many bytes should have been written
469 * This function is called in case of a write failure and moves all good data
470 * from the potentially bad physical eraseblock to a good physical eraseblock.
471 * This function also writes the data which was not written due to the failure.
472 * Returns new physical eraseblock number in case of success, and a negative
473 * error code in case of failure.
475 static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum,
476 const void *buf, int offset, int len)
478 int err, idx = vol_id2idx(ubi, vol_id), new_pnum, data_size, tries = 0;
479 struct ubi_volume *vol = ubi->volumes[idx];
480 struct ubi_vid_hdr *vid_hdr;
482 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
487 mutex_lock(&ubi->buf_mutex);
490 new_pnum = ubi_wl_get_peb(ubi, UBI_UNKNOWN);
492 mutex_unlock(&ubi->buf_mutex);
493 ubi_free_vid_hdr(ubi, vid_hdr);
497 ubi_msg("recover PEB %d, move data to PEB %d", pnum, new_pnum);
499 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1);
500 if (err && err != UBI_IO_BITFLIPS) {
506 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
507 err = ubi_io_write_vid_hdr(ubi, new_pnum, vid_hdr);
511 data_size = offset + len;
512 memset(ubi->peb_buf1 + offset, 0xFF, len);
514 /* Read everything before the area where the write failure happened */
516 err = ubi_io_read_data(ubi, ubi->peb_buf1, pnum, 0, offset);
517 if (err && err != UBI_IO_BITFLIPS)
521 memcpy(ubi->peb_buf1 + offset, buf, len);
523 err = ubi_io_write_data(ubi, ubi->peb_buf1, new_pnum, 0, data_size);
527 mutex_unlock(&ubi->buf_mutex);
528 ubi_free_vid_hdr(ubi, vid_hdr);
530 vol->eba_tbl[lnum] = new_pnum;
531 ubi_wl_put_peb(ubi, pnum, 1);
533 ubi_msg("data was successfully recovered");
537 mutex_unlock(&ubi->buf_mutex);
538 ubi_wl_put_peb(ubi, new_pnum, 1);
539 ubi_free_vid_hdr(ubi, vid_hdr);
544 * Bad luck? This physical eraseblock is bad too? Crud. Let's try to
547 ubi_warn("failed to write to PEB %d", new_pnum);
548 ubi_wl_put_peb(ubi, new_pnum, 1);
549 if (++tries > UBI_IO_RETRIES) {
550 mutex_unlock(&ubi->buf_mutex);
551 ubi_free_vid_hdr(ubi, vid_hdr);
554 ubi_msg("try again");
559 * ubi_eba_write_leb - write data to dynamic volume.
560 * @ubi: UBI device description object
561 * @vol: volume description object
562 * @lnum: logical eraseblock number
563 * @buf: the data to write
564 * @offset: offset within the logical eraseblock where to write
565 * @len: how many bytes to write
568 * This function writes data to logical eraseblock @lnum of a dynamic volume
569 * @vol. Returns zero in case of success and a negative error code in case
570 * of failure. In case of error, it is possible that something was still
571 * written to the flash media, but may be some garbage.
573 int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
574 const void *buf, int offset, int len, int dtype)
576 int err, pnum, tries = 0, vol_id = vol->vol_id;
577 struct ubi_vid_hdr *vid_hdr;
579 ubi_assert(vol->ref_count > 0);
584 err = leb_write_lock(ubi, vol_id, lnum);
588 pnum = vol->eba_tbl[lnum];
590 dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d",
591 len, offset, vol_id, lnum, pnum);
593 err = ubi_io_write_data(ubi, buf, pnum, offset, len);
595 ubi_warn("failed to write data to PEB %d", pnum);
596 if (err == -EIO && ubi->bad_allowed)
597 err = recover_peb(ubi, pnum, vol_id, lnum, buf,
602 leb_write_unlock(ubi, vol_id, lnum);
607 * The logical eraseblock is not mapped. We have to get a free physical
608 * eraseblock and write the volume identifier header there first.
610 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
612 leb_write_unlock(ubi, vol_id, lnum);
616 vid_hdr->vol_type = UBI_VID_DYNAMIC;
617 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
618 vid_hdr->vol_id = cpu_to_be32(vol_id);
619 vid_hdr->lnum = cpu_to_be32(lnum);
620 vid_hdr->compat = ubi_get_compat(ubi, vol_id);
621 vid_hdr->data_pad = cpu_to_be32(vol->data_pad);
624 pnum = ubi_wl_get_peb(ubi, dtype);
626 ubi_free_vid_hdr(ubi, vid_hdr);
627 leb_write_unlock(ubi, vol_id, lnum);
631 dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d",
632 len, offset, vol_id, lnum, pnum);
634 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
636 ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
642 err = ubi_io_write_data(ubi, buf, pnum, offset, len);
644 ubi_warn("failed to write %d bytes at offset %d of "
645 "LEB %d:%d, PEB %d", len, offset, vol_id,
651 vol->eba_tbl[lnum] = pnum;
653 leb_write_unlock(ubi, vol_id, lnum);
654 ubi_free_vid_hdr(ubi, vid_hdr);
658 if (err != -EIO || !ubi->bad_allowed) {
660 leb_write_unlock(ubi, vol_id, lnum);
661 ubi_free_vid_hdr(ubi, vid_hdr);
666 * Fortunately, this is the first write operation to this physical
667 * eraseblock, so just put it and request a new one. We assume that if
668 * this physical eraseblock went bad, the erase code will handle that.
670 err = ubi_wl_put_peb(ubi, pnum, 1);
671 if (err || ++tries > UBI_IO_RETRIES) {
673 leb_write_unlock(ubi, vol_id, lnum);
674 ubi_free_vid_hdr(ubi, vid_hdr);
678 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
679 ubi_msg("try another PEB");
684 * ubi_eba_write_leb_st - write data to static volume.
685 * @ubi: UBI device description object
686 * @vol: volume description object
687 * @lnum: logical eraseblock number
688 * @buf: data to write
689 * @len: how many bytes to write
691 * @used_ebs: how many logical eraseblocks will this volume contain
693 * This function writes data to logical eraseblock @lnum of static volume
694 * @vol. The @used_ebs argument should contain total number of logical
695 * eraseblock in this static volume.
697 * When writing to the last logical eraseblock, the @len argument doesn't have
698 * to be aligned to the minimal I/O unit size. Instead, it has to be equivalent
699 * to the real data size, although the @buf buffer has to contain the
700 * alignment. In all other cases, @len has to be aligned.
702 * It is prohibited to write more then once to logical eraseblocks of static
703 * volumes. This function returns zero in case of success and a negative error
704 * code in case of failure.
706 int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol,
707 int lnum, const void *buf, int len, int dtype,
710 int err, pnum, tries = 0, data_size = len, vol_id = vol->vol_id;
711 struct ubi_vid_hdr *vid_hdr;
714 ubi_assert(vol->ref_count > 0);
719 if (lnum == used_ebs - 1)
720 /* If this is the last LEB @len may be unaligned */
721 len = ALIGN(data_size, ubi->min_io_size);
723 ubi_assert(len % ubi->min_io_size == 0);
725 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
729 err = leb_write_lock(ubi, vol_id, lnum);
731 ubi_free_vid_hdr(ubi, vid_hdr);
735 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
736 vid_hdr->vol_id = cpu_to_be32(vol_id);
737 vid_hdr->lnum = cpu_to_be32(lnum);
738 vid_hdr->compat = ubi_get_compat(ubi, vol_id);
739 vid_hdr->data_pad = cpu_to_be32(vol->data_pad);
741 crc = crc32(UBI_CRC32_INIT, buf, data_size);
742 vid_hdr->vol_type = UBI_VID_STATIC;
743 vid_hdr->data_size = cpu_to_be32(data_size);
744 vid_hdr->used_ebs = cpu_to_be32(used_ebs);
745 vid_hdr->data_crc = cpu_to_be32(crc);
748 pnum = ubi_wl_get_peb(ubi, dtype);
750 ubi_free_vid_hdr(ubi, vid_hdr);
751 leb_write_unlock(ubi, vol_id, lnum);
755 dbg_eba("write VID hdr and %d bytes at LEB %d:%d, PEB %d, used_ebs %d",
756 len, vol_id, lnum, pnum, used_ebs);
758 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
760 ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
765 err = ubi_io_write_data(ubi, buf, pnum, 0, len);
767 ubi_warn("failed to write %d bytes of data to PEB %d",
772 ubi_assert(vol->eba_tbl[lnum] < 0);
773 vol->eba_tbl[lnum] = pnum;
775 leb_write_unlock(ubi, vol_id, lnum);
776 ubi_free_vid_hdr(ubi, vid_hdr);
780 if (err != -EIO || !ubi->bad_allowed) {
782 * This flash device does not admit of bad eraseblocks or
783 * something nasty and unexpected happened. Switch to read-only
787 leb_write_unlock(ubi, vol_id, lnum);
788 ubi_free_vid_hdr(ubi, vid_hdr);
792 err = ubi_wl_put_peb(ubi, pnum, 1);
793 if (err || ++tries > UBI_IO_RETRIES) {
795 leb_write_unlock(ubi, vol_id, lnum);
796 ubi_free_vid_hdr(ubi, vid_hdr);
800 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
801 ubi_msg("try another PEB");
806 * ubi_eba_atomic_leb_change - change logical eraseblock atomically.
807 * @ubi: UBI device description object
808 * @vol: volume description object
809 * @lnum: logical eraseblock number
810 * @buf: data to write
811 * @len: how many bytes to write
814 * This function changes the contents of a logical eraseblock atomically. @buf
815 * has to contain new logical eraseblock data, and @len - the length of the
816 * data, which has to be aligned. This function guarantees that in case of an
817 * unclean reboot the old contents is preserved. Returns zero in case of
818 * success and a negative error code in case of failure.
820 * UBI reserves one LEB for the "atomic LEB change" operation, so only one
821 * LEB change may be done at a time. This is ensured by @ubi->alc_mutex.
823 int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
824 int lnum, const void *buf, int len, int dtype)
826 int err, pnum, tries = 0, vol_id = vol->vol_id;
827 struct ubi_vid_hdr *vid_hdr;
830 ubi_assert(vol->ref_count > 0);
835 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
839 mutex_lock(&ubi->alc_mutex);
840 err = leb_write_lock(ubi, vol_id, lnum);
844 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
845 vid_hdr->vol_id = cpu_to_be32(vol_id);
846 vid_hdr->lnum = cpu_to_be32(lnum);
847 vid_hdr->compat = ubi_get_compat(ubi, vol_id);
848 vid_hdr->data_pad = cpu_to_be32(vol->data_pad);
850 crc = crc32(UBI_CRC32_INIT, buf, len);
851 vid_hdr->vol_type = UBI_VID_DYNAMIC;
852 vid_hdr->data_size = cpu_to_be32(len);
853 vid_hdr->copy_flag = 1;
854 vid_hdr->data_crc = cpu_to_be32(crc);
857 pnum = ubi_wl_get_peb(ubi, dtype);
863 dbg_eba("change LEB %d:%d, PEB %d, write VID hdr to PEB %d",
864 vol_id, lnum, vol->eba_tbl[lnum], pnum);
866 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr);
868 ubi_warn("failed to write VID header to LEB %d:%d, PEB %d",
873 err = ubi_io_write_data(ubi, buf, pnum, 0, len);
875 ubi_warn("failed to write %d bytes of data to PEB %d",
880 if (vol->eba_tbl[lnum] >= 0) {
881 err = ubi_wl_put_peb(ubi, vol->eba_tbl[lnum], 1);
886 vol->eba_tbl[lnum] = pnum;
889 leb_write_unlock(ubi, vol_id, lnum);
891 mutex_unlock(&ubi->alc_mutex);
892 ubi_free_vid_hdr(ubi, vid_hdr);
896 if (err != -EIO || !ubi->bad_allowed) {
898 * This flash device does not admit of bad eraseblocks or
899 * something nasty and unexpected happened. Switch to read-only
906 err = ubi_wl_put_peb(ubi, pnum, 1);
907 if (err || ++tries > UBI_IO_RETRIES) {
912 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
913 ubi_msg("try another PEB");
918 * ubi_eba_copy_leb - copy logical eraseblock.
919 * @ubi: UBI device description object
920 * @from: physical eraseblock number from where to copy
921 * @to: physical eraseblock number where to copy
922 * @vid_hdr: VID header of the @from physical eraseblock
924 * This function copies logical eraseblock from physical eraseblock @from to
925 * physical eraseblock @to. The @vid_hdr buffer may be changed by this
926 * function. Returns zero in case of success, %UBI_IO_BITFLIPS if the operation
927 * was canceled because bit-flips were detected at the target PEB, and a
928 * negative error code in case of failure.
930 int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
931 struct ubi_vid_hdr *vid_hdr)
933 int err, vol_id, lnum, data_size, aldata_size, pnum, idx;
934 struct ubi_volume *vol;
937 vol_id = be32_to_cpu(vid_hdr->vol_id);
938 lnum = be32_to_cpu(vid_hdr->lnum);
940 dbg_eba("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to);
942 if (vid_hdr->vol_type == UBI_VID_STATIC) {
943 data_size = be32_to_cpu(vid_hdr->data_size);
944 aldata_size = ALIGN(data_size, ubi->min_io_size);
946 data_size = aldata_size =
947 ubi->leb_size - be32_to_cpu(vid_hdr->data_pad);
950 * We do not want anybody to write to this logical eraseblock while we
951 * are moving it, so we lock it.
953 err = leb_write_lock(ubi, vol_id, lnum);
957 mutex_lock(&ubi->buf_mutex);
960 * But the logical eraseblock might have been put by this time.
961 * Cancel if it is true.
963 idx = vol_id2idx(ubi, vol_id);
966 * We may race with volume deletion/re-size, so we have to hold
967 * @ubi->volumes_lock.
969 * Note, it is not a problem if we race with volume deletion or re-size
970 * here. If the volume is deleted or re-sized while we are moving an
971 * eraseblock which belongs to this volume, we'll end up with finding
972 * out that this LEB was unmapped at the end (see WL), and drop this
975 spin_lock(&ubi->volumes_lock);
976 vol = ubi->volumes[idx];
978 dbg_eba("volume %d was removed meanwhile", vol_id);
979 spin_unlock(&ubi->volumes_lock);
983 pnum = vol->eba_tbl[lnum];
985 dbg_eba("LEB %d:%d is no longer mapped to PEB %d, mapped to "
986 "PEB %d, cancel", vol_id, lnum, from, pnum);
987 spin_unlock(&ubi->volumes_lock);
990 spin_unlock(&ubi->volumes_lock);
992 /* OK, now the LEB is locked and we can safely start moving it */
994 dbg_eba("read %d bytes of data", aldata_size);
995 err = ubi_io_read_data(ubi, ubi->peb_buf1, from, 0, aldata_size);
996 if (err && err != UBI_IO_BITFLIPS) {
997 ubi_warn("error %d while reading data from PEB %d",
1003 * Now we have got to calculate how much data we have to to copy. In
1004 * case of a static volume it is fairly easy - the VID header contains
1005 * the data size. In case of a dynamic volume it is more difficult - we
1006 * have to read the contents, cut 0xFF bytes from the end and copy only
1007 * the first part. We must do this to avoid writing 0xFF bytes as it
1008 * may have some side-effects. And not only this. It is important not
1009 * to include those 0xFFs to CRC because later the they may be filled
1012 if (vid_hdr->vol_type == UBI_VID_DYNAMIC)
1013 aldata_size = data_size =
1014 ubi_calc_data_len(ubi, ubi->peb_buf1, data_size);
1017 crc = crc32(UBI_CRC32_INIT, ubi->peb_buf1, data_size);
1021 * It may turn out to me that the whole @from physical eraseblock
1022 * contains only 0xFF bytes. Then we have to only write the VID header
1023 * and do not write any data. This also means we should not set
1024 * @vid_hdr->copy_flag, @vid_hdr->data_size, and @vid_hdr->data_crc.
1026 if (data_size > 0) {
1027 vid_hdr->copy_flag = 1;
1028 vid_hdr->data_size = cpu_to_be32(data_size);
1029 vid_hdr->data_crc = cpu_to_be32(crc);
1031 vid_hdr->sqnum = cpu_to_be64(next_sqnum(ubi));
1033 err = ubi_io_write_vid_hdr(ubi, to, vid_hdr);
1039 /* Read the VID header back and check if it was written correctly */
1040 err = ubi_io_read_vid_hdr(ubi, to, vid_hdr, 1);
1042 if (err != UBI_IO_BITFLIPS)
1043 ubi_warn("cannot read VID header back from PEB %d", to);
1047 if (data_size > 0) {
1048 err = ubi_io_write_data(ubi, ubi->peb_buf1, to, 0, aldata_size);
1055 * We've written the data and are going to read it back to make
1056 * sure it was written correctly.
1059 err = ubi_io_read_data(ubi, ubi->peb_buf2, to, 0, aldata_size);
1061 if (err != UBI_IO_BITFLIPS)
1062 ubi_warn("cannot read data back from PEB %d",
1069 if (memcmp(ubi->peb_buf1, ubi->peb_buf2, aldata_size)) {
1070 ubi_warn("read data back from PEB %d - it is different",
1076 ubi_assert(vol->eba_tbl[lnum] == from);
1077 vol->eba_tbl[lnum] = to;
1080 mutex_unlock(&ubi->buf_mutex);
1081 leb_write_unlock(ubi, vol_id, lnum);
1086 * ubi_eba_init_scan - initialize the EBA unit using scanning information.
1087 * @ubi: UBI device description object
1088 * @si: scanning information
1090 * This function returns zero in case of success and a negative error code in
1093 int ubi_eba_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
1095 int i, j, err, num_volumes;
1096 struct ubi_scan_volume *sv;
1097 struct ubi_volume *vol;
1098 struct ubi_scan_leb *seb;
1101 dbg_eba("initialize EBA unit");
1103 spin_lock_init(&ubi->ltree_lock);
1104 mutex_init(&ubi->alc_mutex);
1105 ubi->ltree = RB_ROOT;
1107 ubi->global_sqnum = si->max_sqnum + 1;
1108 num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
1110 for (i = 0; i < num_volumes; i++) {
1111 vol = ubi->volumes[i];
1117 vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int),
1119 if (!vol->eba_tbl) {
1124 for (j = 0; j < vol->reserved_pebs; j++)
1125 vol->eba_tbl[j] = UBI_LEB_UNMAPPED;
1127 sv = ubi_scan_find_sv(si, idx2vol_id(ubi, i));
1131 ubi_rb_for_each_entry(rb, seb, &sv->root, u.rb) {
1132 if (seb->lnum >= vol->reserved_pebs)
1134 * This may happen in case of an unclean reboot
1137 ubi_scan_move_to_list(sv, seb, &si->erase);
1138 vol->eba_tbl[seb->lnum] = seb->pnum;
1142 if (ubi->avail_pebs < EBA_RESERVED_PEBS) {
1143 ubi_err("no enough physical eraseblocks (%d, need %d)",
1144 ubi->avail_pebs, EBA_RESERVED_PEBS);
1148 ubi->avail_pebs -= EBA_RESERVED_PEBS;
1149 ubi->rsvd_pebs += EBA_RESERVED_PEBS;
1151 if (ubi->bad_allowed) {
1152 ubi_calculate_reserved(ubi);
1154 if (ubi->avail_pebs < ubi->beb_rsvd_level) {
1155 /* No enough free physical eraseblocks */
1156 ubi->beb_rsvd_pebs = ubi->avail_pebs;
1157 ubi_warn("cannot reserve enough PEBs for bad PEB "
1158 "handling, reserved %d, need %d",
1159 ubi->beb_rsvd_pebs, ubi->beb_rsvd_level);
1161 ubi->beb_rsvd_pebs = ubi->beb_rsvd_level;
1163 ubi->avail_pebs -= ubi->beb_rsvd_pebs;
1164 ubi->rsvd_pebs += ubi->beb_rsvd_pebs;
1167 dbg_eba("EBA unit is initialized");
1171 for (i = 0; i < num_volumes; i++) {
1172 if (!ubi->volumes[i])
1174 kfree(ubi->volumes[i]->eba_tbl);
1180 * ubi_eba_close - close EBA unit.
1181 * @ubi: UBI device description object
1183 void ubi_eba_close(const struct ubi_device *ubi)
1185 int i, num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
1187 dbg_eba("close EBA unit");
1189 for (i = 0; i < num_volumes; i++) {
1190 if (!ubi->volumes[i])
1192 kfree(ubi->volumes[i]->eba_tbl);