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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2012 Linutronix GmbH
   4 * Copyright (c) 2014 sigma star gmbh
   5 * Author: Richard Weinberger <richard@nod.at>
 
 
 
 
 
 
 
 
 
 
   6 */
   7
   8#include <linux/crc32.h>
   9#include <linux/bitmap.h>
  10#include "ubi.h"
  11
  12/**
  13 * init_seen - allocate memory for used for debugging.
  14 * @ubi: UBI device description object
  15 */
  16static inline unsigned long *init_seen(struct ubi_device *ubi)
  17{
  18	unsigned long *ret;
  19
  20	if (!ubi_dbg_chk_fastmap(ubi))
  21		return NULL;
  22
  23	ret = bitmap_zalloc(ubi->peb_count, GFP_NOFS);
 
  24	if (!ret)
  25		return ERR_PTR(-ENOMEM);
  26
  27	return ret;
  28}
  29
  30/**
  31 * free_seen - free the seen logic integer array.
  32 * @seen: integer array of @ubi->peb_count size
  33 */
  34static inline void free_seen(unsigned long *seen)
  35{
  36	bitmap_free(seen);
  37}
  38
  39/**
  40 * set_seen - mark a PEB as seen.
  41 * @ubi: UBI device description object
  42 * @pnum: The PEB to be makred as seen
  43 * @seen: integer array of @ubi->peb_count size
  44 */
  45static inline void set_seen(struct ubi_device *ubi, int pnum, unsigned long *seen)
  46{
  47	if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  48		return;
  49
  50	set_bit(pnum, seen);
  51}
  52
  53/**
  54 * self_check_seen - check whether all PEB have been seen by fastmap.
  55 * @ubi: UBI device description object
  56 * @seen: integer array of @ubi->peb_count size
  57 */
  58static int self_check_seen(struct ubi_device *ubi, unsigned long *seen)
  59{
  60	int pnum, ret = 0;
  61
  62	if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  63		return 0;
  64
  65	for (pnum = 0; pnum < ubi->peb_count; pnum++) {
  66		if (!test_bit(pnum, seen) && ubi->lookuptbl[pnum]) {
  67			ubi_err(ubi, "self-check failed for PEB %d, fastmap didn't see it", pnum);
  68			ret = -EINVAL;
  69		}
  70	}
  71
  72	return ret;
  73}
  74
  75/**
  76 * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
  77 * @ubi: UBI device description object
  78 */
  79size_t ubi_calc_fm_size(struct ubi_device *ubi)
  80{
  81	size_t size;
  82
  83	size = sizeof(struct ubi_fm_sb) +
  84		sizeof(struct ubi_fm_hdr) +
  85		sizeof(struct ubi_fm_scan_pool) +
  86		sizeof(struct ubi_fm_scan_pool) +
  87		(ubi->peb_count * sizeof(struct ubi_fm_ec)) +
  88		(sizeof(struct ubi_fm_eba) +
  89		(ubi->peb_count * sizeof(__be32))) +
  90		sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
  91	return roundup(size, ubi->leb_size);
  92}
  93
  94
  95/**
  96 * new_fm_vbuf() - allocate a new volume header for fastmap usage.
  97 * @ubi: UBI device description object
  98 * @vol_id: the VID of the new header
  99 *
 100 * Returns a new struct ubi_vid_hdr on success.
 101 * NULL indicates out of memory.
 102 */
 103static struct ubi_vid_io_buf *new_fm_vbuf(struct ubi_device *ubi, int vol_id)
 104{
 105	struct ubi_vid_io_buf *new;
 106	struct ubi_vid_hdr *vh;
 107
 108	new = ubi_alloc_vid_buf(ubi, GFP_NOFS);
 109	if (!new)
 110		goto out;
 111
 112	vh = ubi_get_vid_hdr(new);
 113	vh->vol_type = UBI_VID_DYNAMIC;
 114	vh->vol_id = cpu_to_be32(vol_id);
 115
 116	/* UBI implementations without fastmap support have to delete the
 117	 * fastmap.
 118	 */
 119	vh->compat = UBI_COMPAT_DELETE;
 120
 121out:
 122	return new;
 123}
 124
 125/**
 126 * add_aeb - create and add a attach erase block to a given list.
 127 * @ai: UBI attach info object
 128 * @list: the target list
 129 * @pnum: PEB number of the new attach erase block
 130 * @ec: erease counter of the new LEB
 131 * @scrub: scrub this PEB after attaching
 132 *
 133 * Returns 0 on success, < 0 indicates an internal error.
 134 */
 135static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
 136		   int pnum, int ec, int scrub)
 137{
 138	struct ubi_ainf_peb *aeb;
 139
 140	aeb = ubi_alloc_aeb(ai, pnum, ec);
 141	if (!aeb)
 142		return -ENOMEM;
 143
 144	aeb->lnum = -1;
 145	aeb->scrub = scrub;
 146	aeb->copy_flag = aeb->sqnum = 0;
 147
 148	ai->ec_sum += aeb->ec;
 149	ai->ec_count++;
 150
 151	if (ai->max_ec < aeb->ec)
 152		ai->max_ec = aeb->ec;
 153
 154	if (ai->min_ec > aeb->ec)
 155		ai->min_ec = aeb->ec;
 156
 157	list_add_tail(&aeb->u.list, list);
 158
 159	return 0;
 160}
 161
 162/**
 163 * add_vol - create and add a new volume to ubi_attach_info.
 164 * @ai: ubi_attach_info object
 165 * @vol_id: VID of the new volume
 166 * @used_ebs: number of used EBS
 167 * @data_pad: data padding value of the new volume
 168 * @vol_type: volume type
 169 * @last_eb_bytes: number of bytes in the last LEB
 170 *
 171 * Returns the new struct ubi_ainf_volume on success.
 172 * NULL indicates an error.
 173 */
 174static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
 175				       int used_ebs, int data_pad, u8 vol_type,
 176				       int last_eb_bytes)
 177{
 178	struct ubi_ainf_volume *av;
 179
 180	av = ubi_add_av(ai, vol_id);
 181	if (IS_ERR(av))
 182		return av;
 183
 184	av->data_pad = data_pad;
 185	av->last_data_size = last_eb_bytes;
 186	av->compat = 0;
 187	av->vol_type = vol_type;
 188	if (av->vol_type == UBI_STATIC_VOLUME)
 189		av->used_ebs = used_ebs;
 190
 191	dbg_bld("found volume (ID %i)", vol_id);
 192	return av;
 193}
 194
 195/**
 196 * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
 197 * from it's original list.
 198 * @ai: ubi_attach_info object
 199 * @aeb: the to be assigned SEB
 200 * @av: target scan volume
 201 */
 202static void assign_aeb_to_av(struct ubi_attach_info *ai,
 203			     struct ubi_ainf_peb *aeb,
 204			     struct ubi_ainf_volume *av)
 205{
 206	struct ubi_ainf_peb *tmp_aeb;
 207	struct rb_node **p = &av->root.rb_node, *parent = NULL;
 208
 209	while (*p) {
 210		parent = *p;
 211
 212		tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 213		if (aeb->lnum != tmp_aeb->lnum) {
 214			if (aeb->lnum < tmp_aeb->lnum)
 215				p = &(*p)->rb_left;
 216			else
 217				p = &(*p)->rb_right;
 218
 219			continue;
 220		} else
 221			break;
 222	}
 223
 224	list_del(&aeb->u.list);
 225	av->leb_count++;
 226
 227	rb_link_node(&aeb->u.rb, parent, p);
 228	rb_insert_color(&aeb->u.rb, &av->root);
 229}
 230
 231/**
 232 * update_vol - inserts or updates a LEB which was found a pool.
 233 * @ubi: the UBI device object
 234 * @ai: attach info object
 235 * @av: the volume this LEB belongs to
 236 * @new_vh: the volume header derived from new_aeb
 237 * @new_aeb: the AEB to be examined
 238 *
 239 * Returns 0 on success, < 0 indicates an internal error.
 240 */
 241static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
 242		      struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
 243		      struct ubi_ainf_peb *new_aeb)
 244{
 245	struct rb_node **p = &av->root.rb_node, *parent = NULL;
 246	struct ubi_ainf_peb *aeb, *victim;
 247	int cmp_res;
 248
 249	while (*p) {
 250		parent = *p;
 251		aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 252
 253		if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
 254			if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
 255				p = &(*p)->rb_left;
 256			else
 257				p = &(*p)->rb_right;
 258
 259			continue;
 260		}
 261
 262		/* This case can happen if the fastmap gets written
 263		 * because of a volume change (creation, deletion, ..).
 264		 * Then a PEB can be within the persistent EBA and the pool.
 265		 */
 266		if (aeb->pnum == new_aeb->pnum) {
 267			ubi_assert(aeb->lnum == new_aeb->lnum);
 268			ubi_free_aeb(ai, new_aeb);
 269
 270			return 0;
 271		}
 272
 273		cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
 274		if (cmp_res < 0)
 275			return cmp_res;
 276
 277		/* new_aeb is newer */
 278		if (cmp_res & 1) {
 279			victim = ubi_alloc_aeb(ai, aeb->pnum, aeb->ec);
 280			if (!victim)
 281				return -ENOMEM;
 282
 283			list_add_tail(&victim->u.list, &ai->erase);
 284
 285			if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
 286				av->last_data_size =
 287					be32_to_cpu(new_vh->data_size);
 288
 289			dbg_bld("vol %i: AEB %i's PEB %i is the newer",
 290				av->vol_id, aeb->lnum, new_aeb->pnum);
 291
 292			aeb->ec = new_aeb->ec;
 293			aeb->pnum = new_aeb->pnum;
 294			aeb->copy_flag = new_vh->copy_flag;
 295			aeb->scrub = new_aeb->scrub;
 296			aeb->sqnum = new_aeb->sqnum;
 297			ubi_free_aeb(ai, new_aeb);
 298
 299		/* new_aeb is older */
 300		} else {
 301			dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
 302				av->vol_id, aeb->lnum, new_aeb->pnum);
 303			list_add_tail(&new_aeb->u.list, &ai->erase);
 304		}
 305
 306		return 0;
 307	}
 308	/* This LEB is new, let's add it to the volume */
 309
 310	if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
 311		av->highest_lnum = be32_to_cpu(new_vh->lnum);
 312		av->last_data_size = be32_to_cpu(new_vh->data_size);
 313	}
 314
 315	if (av->vol_type == UBI_STATIC_VOLUME)
 316		av->used_ebs = be32_to_cpu(new_vh->used_ebs);
 317
 318	av->leb_count++;
 319
 320	rb_link_node(&new_aeb->u.rb, parent, p);
 321	rb_insert_color(&new_aeb->u.rb, &av->root);
 322
 323	return 0;
 324}
 325
 326/**
 327 * process_pool_aeb - we found a non-empty PEB in a pool.
 328 * @ubi: UBI device object
 329 * @ai: attach info object
 330 * @new_vh: the volume header derived from new_aeb
 331 * @new_aeb: the AEB to be examined
 332 *
 333 * Returns 0 on success, < 0 indicates an internal error.
 334 */
 335static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 336			    struct ubi_vid_hdr *new_vh,
 337			    struct ubi_ainf_peb *new_aeb)
 338{
 339	int vol_id = be32_to_cpu(new_vh->vol_id);
 340	struct ubi_ainf_volume *av;
 341
 342	if (vol_id == UBI_FM_SB_VOLUME_ID || vol_id == UBI_FM_DATA_VOLUME_ID) {
 343		ubi_free_aeb(ai, new_aeb);
 344
 345		return 0;
 346	}
 347
 348	/* Find the volume this SEB belongs to */
 349	av = ubi_find_av(ai, vol_id);
 350	if (!av) {
 351		ubi_err(ubi, "orphaned volume in fastmap pool!");
 352		ubi_free_aeb(ai, new_aeb);
 353		return UBI_BAD_FASTMAP;
 354	}
 355
 356	ubi_assert(vol_id == av->vol_id);
 357
 358	return update_vol(ubi, ai, av, new_vh, new_aeb);
 359}
 360
 361/**
 362 * unmap_peb - unmap a PEB.
 363 * If fastmap detects a free PEB in the pool it has to check whether
 364 * this PEB has been unmapped after writing the fastmap.
 365 *
 366 * @ai: UBI attach info object
 367 * @pnum: The PEB to be unmapped
 368 */
 369static void unmap_peb(struct ubi_attach_info *ai, int pnum)
 370{
 371	struct ubi_ainf_volume *av;
 372	struct rb_node *node, *node2;
 373	struct ubi_ainf_peb *aeb;
 374
 375	ubi_rb_for_each_entry(node, av, &ai->volumes, rb) {
 376		ubi_rb_for_each_entry(node2, aeb, &av->root, u.rb) {
 377			if (aeb->pnum == pnum) {
 378				rb_erase(&aeb->u.rb, &av->root);
 379				av->leb_count--;
 380				ubi_free_aeb(ai, aeb);
 381				return;
 382			}
 383		}
 384	}
 385}
 386
 387/**
 388 * scan_pool - scans a pool for changed (no longer empty PEBs).
 389 * @ubi: UBI device object
 390 * @ai: attach info object
 391 * @pebs: an array of all PEB numbers in the to be scanned pool
 392 * @pool_size: size of the pool (number of entries in @pebs)
 393 * @max_sqnum: pointer to the maximal sequence number
 394 * @free: list of PEBs which are most likely free (and go into @ai->free)
 395 *
 396 * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
 397 * < 0 indicates an internal error.
 398 */
 399static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 400		     __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 401		     struct list_head *free)
 402{
 403	struct ubi_vid_io_buf *vb;
 404	struct ubi_vid_hdr *vh;
 405	struct ubi_ec_hdr *ech;
 406	struct ubi_ainf_peb *new_aeb;
 407	int i, pnum, err, ret = 0;
 408
 409	ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 410	if (!ech)
 411		return -ENOMEM;
 412
 413	vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
 414	if (!vb) {
 415		kfree(ech);
 416		return -ENOMEM;
 417	}
 418
 419	vh = ubi_get_vid_hdr(vb);
 420
 421	dbg_bld("scanning fastmap pool: size = %i", pool_size);
 422
 423	/*
 424	 * Now scan all PEBs in the pool to find changes which have been made
 425	 * after the creation of the fastmap
 426	 */
 427	for (i = 0; i < pool_size; i++) {
 428		int scrub = 0;
 429		int image_seq;
 430
 431		pnum = be32_to_cpu(pebs[i]);
 432
 433		if (ubi_io_is_bad(ubi, pnum)) {
 434			ubi_err(ubi, "bad PEB in fastmap pool!");
 435			ret = UBI_BAD_FASTMAP;
 436			goto out;
 437		}
 438
 439		err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 440		if (err && err != UBI_IO_BITFLIPS) {
 441			ubi_err(ubi, "unable to read EC header! PEB:%i err:%i",
 442				pnum, err);
 443			ret = err > 0 ? UBI_BAD_FASTMAP : err;
 444			goto out;
 445		} else if (err == UBI_IO_BITFLIPS)
 446			scrub = 1;
 447
 448		/*
 449		 * Older UBI implementations have image_seq set to zero, so
 450		 * we shouldn't fail if image_seq == 0.
 451		 */
 452		image_seq = be32_to_cpu(ech->image_seq);
 453
 454		if (image_seq && (image_seq != ubi->image_seq)) {
 455			ubi_err(ubi, "bad image seq: 0x%x, expected: 0x%x",
 456				be32_to_cpu(ech->image_seq), ubi->image_seq);
 457			ret = UBI_BAD_FASTMAP;
 458			goto out;
 459		}
 460
 461		err = ubi_io_read_vid_hdr(ubi, pnum, vb, 0);
 462		if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
 463			unsigned long long ec = be64_to_cpu(ech->ec);
 464			unmap_peb(ai, pnum);
 465			dbg_bld("Adding PEB to free: %i", pnum);
 466
 467			if (err == UBI_IO_FF_BITFLIPS)
 468				scrub = 1;
 469
 470			ret = add_aeb(ai, free, pnum, ec, scrub);
 471			if (ret)
 472				goto out;
 473			continue;
 474		} else if (err == 0 || err == UBI_IO_BITFLIPS) {
 475			dbg_bld("Found non empty PEB:%i in pool", pnum);
 476
 477			if (err == UBI_IO_BITFLIPS)
 478				scrub = 1;
 479
 480			new_aeb = ubi_alloc_aeb(ai, pnum, be64_to_cpu(ech->ec));
 481			if (!new_aeb) {
 482				ret = -ENOMEM;
 483				goto out;
 484			}
 485
 486			new_aeb->lnum = be32_to_cpu(vh->lnum);
 487			new_aeb->sqnum = be64_to_cpu(vh->sqnum);
 488			new_aeb->copy_flag = vh->copy_flag;
 489			new_aeb->scrub = scrub;
 490
 491			if (*max_sqnum < new_aeb->sqnum)
 492				*max_sqnum = new_aeb->sqnum;
 493
 494			err = process_pool_aeb(ubi, ai, vh, new_aeb);
 495			if (err) {
 496				ret = err > 0 ? UBI_BAD_FASTMAP : err;
 497				goto out;
 498			}
 499		} else {
 500			/* We are paranoid and fall back to scanning mode */
 501			ubi_err(ubi, "fastmap pool PEBs contains damaged PEBs!");
 502			ret = err > 0 ? UBI_BAD_FASTMAP : err;
 503			goto out;
 504		}
 505
 506	}
 507
 508out:
 509	ubi_free_vid_buf(vb);
 510	kfree(ech);
 511	return ret;
 512}
 513
 514/**
 515 * count_fastmap_pebs - Counts the PEBs found by fastmap.
 516 * @ai: The UBI attach info object
 517 */
 518static int count_fastmap_pebs(struct ubi_attach_info *ai)
 519{
 520	struct ubi_ainf_peb *aeb;
 521	struct ubi_ainf_volume *av;
 522	struct rb_node *rb1, *rb2;
 523	int n = 0;
 524
 525	list_for_each_entry(aeb, &ai->erase, u.list)
 526		n++;
 527
 528	list_for_each_entry(aeb, &ai->free, u.list)
 529		n++;
 530
 531	ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
 532		ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
 533			n++;
 534
 535	return n;
 536}
 537
 538/**
 539 * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
 540 * @ubi: UBI device object
 541 * @ai: UBI attach info object
 542 * @fm: the fastmap to be attached
 543 *
 544 * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
 545 * < 0 indicates an internal error.
 546 */
 547static int ubi_attach_fastmap(struct ubi_device *ubi,
 548			      struct ubi_attach_info *ai,
 549			      struct ubi_fastmap_layout *fm)
 550{
 551	struct list_head used, free;
 552	struct ubi_ainf_volume *av;
 553	struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
 554	struct ubi_fm_sb *fmsb;
 555	struct ubi_fm_hdr *fmhdr;
 556	struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
 557	struct ubi_fm_ec *fmec;
 558	struct ubi_fm_volhdr *fmvhdr;
 559	struct ubi_fm_eba *fm_eba;
 560	int ret, i, j, pool_size, wl_pool_size;
 561	size_t fm_pos = 0, fm_size = ubi->fm_size;
 562	unsigned long long max_sqnum = 0;
 563	void *fm_raw = ubi->fm_buf;
 564
 565	INIT_LIST_HEAD(&used);
 566	INIT_LIST_HEAD(&free);
 567	ai->min_ec = UBI_MAX_ERASECOUNTER;
 568
 569	fmsb = (struct ubi_fm_sb *)(fm_raw);
 570	ai->max_sqnum = fmsb->sqnum;
 571	fm_pos += sizeof(struct ubi_fm_sb);
 572	if (fm_pos >= fm_size)
 573		goto fail_bad;
 574
 575	fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
 576	fm_pos += sizeof(*fmhdr);
 577	if (fm_pos >= fm_size)
 578		goto fail_bad;
 579
 580	if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
 581		ubi_err(ubi, "bad fastmap header magic: 0x%x, expected: 0x%x",
 582			be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
 583		goto fail_bad;
 584	}
 585
 586	fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 587	fm_pos += sizeof(*fmpl);
 588	if (fm_pos >= fm_size)
 589		goto fail_bad;
 590	if (be32_to_cpu(fmpl->magic) != UBI_FM_POOL_MAGIC) {
 591		ubi_err(ubi, "bad fastmap pool magic: 0x%x, expected: 0x%x",
 592			be32_to_cpu(fmpl->magic), UBI_FM_POOL_MAGIC);
 593		goto fail_bad;
 594	}
 595
 596	fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 597	fm_pos += sizeof(*fmpl_wl);
 598	if (fm_pos >= fm_size)
 599		goto fail_bad;
 600	if (be32_to_cpu(fmpl_wl->magic) != UBI_FM_POOL_MAGIC) {
 601		ubi_err(ubi, "bad fastmap WL pool magic: 0x%x, expected: 0x%x",
 602			be32_to_cpu(fmpl_wl->magic), UBI_FM_POOL_MAGIC);
 603		goto fail_bad;
 604	}
 605
 606	pool_size = be16_to_cpu(fmpl->size);
 607	wl_pool_size = be16_to_cpu(fmpl_wl->size);
 608	fm->max_pool_size = be16_to_cpu(fmpl->max_size);
 609	fm->max_wl_pool_size = be16_to_cpu(fmpl_wl->max_size);
 610
 611	if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
 612		ubi_err(ubi, "bad pool size: %i", pool_size);
 613		goto fail_bad;
 614	}
 615
 616	if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
 617		ubi_err(ubi, "bad WL pool size: %i", wl_pool_size);
 618		goto fail_bad;
 619	}
 620
 621
 622	if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
 623	    fm->max_pool_size < 0) {
 624		ubi_err(ubi, "bad maximal pool size: %i", fm->max_pool_size);
 625		goto fail_bad;
 626	}
 627
 628	if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
 629	    fm->max_wl_pool_size < 0) {
 630		ubi_err(ubi, "bad maximal WL pool size: %i",
 631			fm->max_wl_pool_size);
 632		goto fail_bad;
 633	}
 634
 635	/* read EC values from free list */
 636	for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
 637		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 638		fm_pos += sizeof(*fmec);
 639		if (fm_pos >= fm_size)
 640			goto fail_bad;
 641
 642		ret = add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
 643			      be32_to_cpu(fmec->ec), 0);
 644		if (ret)
 645			goto fail;
 646	}
 647
 648	/* read EC values from used list */
 649	for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
 650		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 651		fm_pos += sizeof(*fmec);
 652		if (fm_pos >= fm_size)
 653			goto fail_bad;
 654
 655		ret = add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 656			      be32_to_cpu(fmec->ec), 0);
 657		if (ret)
 658			goto fail;
 659	}
 660
 661	/* read EC values from scrub list */
 662	for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
 663		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 664		fm_pos += sizeof(*fmec);
 665		if (fm_pos >= fm_size)
 666			goto fail_bad;
 667
 668		ret = add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 669			      be32_to_cpu(fmec->ec), 1);
 670		if (ret)
 671			goto fail;
 672	}
 673
 674	/* read EC values from erase list */
 675	for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
 676		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 677		fm_pos += sizeof(*fmec);
 678		if (fm_pos >= fm_size)
 679			goto fail_bad;
 680
 681		ret = add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
 682			      be32_to_cpu(fmec->ec), 1);
 683		if (ret)
 684			goto fail;
 685	}
 686
 687	ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
 688	ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
 689
 690	/* Iterate over all volumes and read their EBA table */
 691	for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
 692		fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
 693		fm_pos += sizeof(*fmvhdr);
 694		if (fm_pos >= fm_size)
 695			goto fail_bad;
 696
 697		if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
 698			ubi_err(ubi, "bad fastmap vol header magic: 0x%x, expected: 0x%x",
 699				be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
 700			goto fail_bad;
 701		}
 702
 703		av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
 704			     be32_to_cpu(fmvhdr->used_ebs),
 705			     be32_to_cpu(fmvhdr->data_pad),
 706			     fmvhdr->vol_type,
 707			     be32_to_cpu(fmvhdr->last_eb_bytes));
 708
 709		if (IS_ERR(av)) {
 710			if (PTR_ERR(av) == -EEXIST)
 711				ubi_err(ubi, "volume (ID %i) already exists",
 712					fmvhdr->vol_id);
 713
 714			goto fail_bad;
 715		}
 716
 717		ai->vols_found++;
 718		if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
 719			ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
 720
 721		fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
 722		fm_pos += sizeof(*fm_eba);
 723		fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
 724		if (fm_pos >= fm_size)
 725			goto fail_bad;
 726
 727		if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
 728			ubi_err(ubi, "bad fastmap EBA header magic: 0x%x, expected: 0x%x",
 729				be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
 730			goto fail_bad;
 731		}
 732
 733		for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
 734			int pnum = be32_to_cpu(fm_eba->pnum[j]);
 735
 736			if (pnum < 0)
 737				continue;
 738
 739			aeb = NULL;
 740			list_for_each_entry(tmp_aeb, &used, u.list) {
 741				if (tmp_aeb->pnum == pnum) {
 742					aeb = tmp_aeb;
 743					break;
 744				}
 745			}
 746
 747			if (!aeb) {
 748				ubi_err(ubi, "PEB %i is in EBA but not in used list", pnum);
 749				goto fail_bad;
 750			}
 751
 752			aeb->lnum = j;
 753
 754			if (av->highest_lnum <= aeb->lnum)
 755				av->highest_lnum = aeb->lnum;
 756
 757			assign_aeb_to_av(ai, aeb, av);
 758
 759			dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
 760				aeb->pnum, aeb->lnum, av->vol_id);
 761		}
 762	}
 763
 764	ret = scan_pool(ubi, ai, fmpl->pebs, pool_size, &max_sqnum, &free);
 765	if (ret)
 766		goto fail;
 767
 768	ret = scan_pool(ubi, ai, fmpl_wl->pebs, wl_pool_size, &max_sqnum, &free);
 769	if (ret)
 770		goto fail;
 771
 772	if (max_sqnum > ai->max_sqnum)
 773		ai->max_sqnum = max_sqnum;
 774
 775	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list)
 776		list_move_tail(&tmp_aeb->u.list, &ai->free);
 777
 778	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list)
 779		list_move_tail(&tmp_aeb->u.list, &ai->erase);
 780
 781	ubi_assert(list_empty(&free));
 782
 783	/*
 784	 * If fastmap is leaking PEBs (must not happen), raise a
 785	 * fat warning and fall back to scanning mode.
 786	 * We do this here because in ubi_wl_init() it's too late
 787	 * and we cannot fall back to scanning.
 788	 */
 789	if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
 790		    ai->bad_peb_count - fm->used_blocks))
 791		goto fail_bad;
 792
 793	return 0;
 794
 795fail_bad:
 796	ret = UBI_BAD_FASTMAP;
 797fail:
 798	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) {
 799		list_del(&tmp_aeb->u.list);
 800		ubi_free_aeb(ai, tmp_aeb);
 801	}
 802	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) {
 803		list_del(&tmp_aeb->u.list);
 804		ubi_free_aeb(ai, tmp_aeb);
 805	}
 806
 807	return ret;
 808}
 809
 810/**
 811 * find_fm_anchor - find the most recent Fastmap superblock (anchor)
 812 * @ai: UBI attach info to be filled
 813 */
 814static int find_fm_anchor(struct ubi_attach_info *ai)
 815{
 816	int ret = -1;
 817	struct ubi_ainf_peb *aeb;
 818	unsigned long long max_sqnum = 0;
 819
 820	list_for_each_entry(aeb, &ai->fastmap, u.list) {
 821		if (aeb->vol_id == UBI_FM_SB_VOLUME_ID && aeb->sqnum > max_sqnum) {
 822			max_sqnum = aeb->sqnum;
 823			ret = aeb->pnum;
 824		}
 825	}
 826
 827	return ret;
 828}
 829
 830static struct ubi_ainf_peb *clone_aeb(struct ubi_attach_info *ai,
 831				      struct ubi_ainf_peb *old)
 832{
 833	struct ubi_ainf_peb *new;
 834
 835	new = ubi_alloc_aeb(ai, old->pnum, old->ec);
 836	if (!new)
 837		return NULL;
 838
 839	new->vol_id = old->vol_id;
 840	new->sqnum = old->sqnum;
 841	new->lnum = old->lnum;
 842	new->scrub = old->scrub;
 843	new->copy_flag = old->copy_flag;
 844
 845	return new;
 846}
 847
 848/**
 849 * ubi_scan_fastmap - scan the fastmap.
 850 * @ubi: UBI device object
 851 * @ai: UBI attach info to be filled
 852 * @scan_ai: UBI attach info from the first 64 PEBs,
 853 *           used to find the most recent Fastmap data structure
 854 *
 855 * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
 856 * UBI_BAD_FASTMAP if one was found but is not usable.
 857 * < 0 indicates an internal error.
 858 */
 859int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 860		     struct ubi_attach_info *scan_ai)
 861{
 862	struct ubi_fm_sb *fmsb, *fmsb2;
 863	struct ubi_vid_io_buf *vb;
 864	struct ubi_vid_hdr *vh;
 865	struct ubi_ec_hdr *ech;
 866	struct ubi_fastmap_layout *fm;
 867	struct ubi_ainf_peb *aeb;
 868	int i, used_blocks, pnum, fm_anchor, ret = 0;
 869	size_t fm_size;
 870	__be32 crc, tmp_crc;
 871	unsigned long long sqnum = 0;
 872
 873	fm_anchor = find_fm_anchor(scan_ai);
 874	if (fm_anchor < 0)
 875		return UBI_NO_FASTMAP;
 876
 877	/* Copy all (possible) fastmap blocks into our new attach structure. */
 878	list_for_each_entry(aeb, &scan_ai->fastmap, u.list) {
 879		struct ubi_ainf_peb *new;
 880
 881		new = clone_aeb(ai, aeb);
 882		if (!new)
 883			return -ENOMEM;
 884
 885		list_add(&new->u.list, &ai->fastmap);
 886	}
 887
 888	down_write(&ubi->fm_protect);
 889	memset(ubi->fm_buf, 0, ubi->fm_size);
 890
 891	fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
 892	if (!fmsb) {
 893		ret = -ENOMEM;
 894		goto out;
 895	}
 896
 897	fm = kzalloc(sizeof(*fm), GFP_KERNEL);
 898	if (!fm) {
 899		ret = -ENOMEM;
 900		kfree(fmsb);
 901		goto out;
 902	}
 903
 904	ret = ubi_io_read_data(ubi, fmsb, fm_anchor, 0, sizeof(*fmsb));
 905	if (ret && ret != UBI_IO_BITFLIPS)
 906		goto free_fm_sb;
 907	else if (ret == UBI_IO_BITFLIPS)
 908		fm->to_be_tortured[0] = 1;
 909
 910	if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
 911		ubi_err(ubi, "bad super block magic: 0x%x, expected: 0x%x",
 912			be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
 913		ret = UBI_BAD_FASTMAP;
 914		goto free_fm_sb;
 915	}
 916
 917	if (fmsb->version != UBI_FM_FMT_VERSION) {
 918		ubi_err(ubi, "bad fastmap version: %i, expected: %i",
 919			fmsb->version, UBI_FM_FMT_VERSION);
 920		ret = UBI_BAD_FASTMAP;
 921		goto free_fm_sb;
 922	}
 923
 924	used_blocks = be32_to_cpu(fmsb->used_blocks);
 925	if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
 926		ubi_err(ubi, "number of fastmap blocks is invalid: %i",
 927			used_blocks);
 928		ret = UBI_BAD_FASTMAP;
 929		goto free_fm_sb;
 930	}
 931
 932	fm_size = ubi->leb_size * used_blocks;
 933	if (fm_size != ubi->fm_size) {
 934		ubi_err(ubi, "bad fastmap size: %zi, expected: %zi",
 935			fm_size, ubi->fm_size);
 936		ret = UBI_BAD_FASTMAP;
 937		goto free_fm_sb;
 938	}
 939
 940	ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 941	if (!ech) {
 942		ret = -ENOMEM;
 943		goto free_fm_sb;
 944	}
 945
 946	vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
 947	if (!vb) {
 948		ret = -ENOMEM;
 949		goto free_hdr;
 950	}
 951
 952	vh = ubi_get_vid_hdr(vb);
 953
 954	for (i = 0; i < used_blocks; i++) {
 955		int image_seq;
 956
 957		pnum = be32_to_cpu(fmsb->block_loc[i]);
 958
 959		if (ubi_io_is_bad(ubi, pnum)) {
 960			ret = UBI_BAD_FASTMAP;
 961			goto free_hdr;
 962		}
 963
 964		if (i == 0 && pnum != fm_anchor) {
 965			ubi_err(ubi, "Fastmap anchor PEB mismatch: PEB: %i vs. %i",
 966				pnum, fm_anchor);
 967			ret = UBI_BAD_FASTMAP;
 968			goto free_hdr;
 969		}
 970
 971		ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 972		if (ret && ret != UBI_IO_BITFLIPS) {
 973			ubi_err(ubi, "unable to read fastmap block# %i EC (PEB: %i)",
 974				i, pnum);
 975			if (ret > 0)
 976				ret = UBI_BAD_FASTMAP;
 977			goto free_hdr;
 978		} else if (ret == UBI_IO_BITFLIPS)
 979			fm->to_be_tortured[i] = 1;
 980
 981		image_seq = be32_to_cpu(ech->image_seq);
 982		if (!ubi->image_seq)
 983			ubi->image_seq = image_seq;
 984
 985		/*
 986		 * Older UBI implementations have image_seq set to zero, so
 987		 * we shouldn't fail if image_seq == 0.
 988		 */
 989		if (image_seq && (image_seq != ubi->image_seq)) {
 990			ubi_err(ubi, "wrong image seq:%d instead of %d",
 991				be32_to_cpu(ech->image_seq), ubi->image_seq);
 992			ret = UBI_BAD_FASTMAP;
 993			goto free_hdr;
 994		}
 995
 996		ret = ubi_io_read_vid_hdr(ubi, pnum, vb, 0);
 997		if (ret && ret != UBI_IO_BITFLIPS) {
 998			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i)",
 999				i, pnum);
1000			goto free_hdr;
1001		}
1002
1003		if (i == 0) {
1004			if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
1005				ubi_err(ubi, "bad fastmap anchor vol_id: 0x%x, expected: 0x%x",
1006					be32_to_cpu(vh->vol_id),
1007					UBI_FM_SB_VOLUME_ID);
1008				ret = UBI_BAD_FASTMAP;
1009				goto free_hdr;
1010			}
1011		} else {
1012			if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
1013				ubi_err(ubi, "bad fastmap data vol_id: 0x%x, expected: 0x%x",
1014					be32_to_cpu(vh->vol_id),
1015					UBI_FM_DATA_VOLUME_ID);
1016				ret = UBI_BAD_FASTMAP;
1017				goto free_hdr;
1018			}
1019		}
1020
1021		if (sqnum < be64_to_cpu(vh->sqnum))
1022			sqnum = be64_to_cpu(vh->sqnum);
1023
1024		ret = ubi_io_read_data(ubi, ubi->fm_buf + (ubi->leb_size * i),
1025				       pnum, 0, ubi->leb_size);
1026		if (ret && ret != UBI_IO_BITFLIPS) {
1027			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i, "
1028				"err: %i)", i, pnum, ret);
1029			goto free_hdr;
1030		}
1031	}
1032
1033	kfree(fmsb);
1034	fmsb = NULL;
1035
1036	fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
1037	tmp_crc = be32_to_cpu(fmsb2->data_crc);
1038	fmsb2->data_crc = 0;
1039	crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
1040	if (crc != tmp_crc) {
1041		ubi_err(ubi, "fastmap data CRC is invalid");
1042		ubi_err(ubi, "CRC should be: 0x%x, calc: 0x%x",
1043			tmp_crc, crc);
1044		ret = UBI_BAD_FASTMAP;
1045		goto free_hdr;
1046	}
1047
1048	fmsb2->sqnum = sqnum;
1049
1050	fm->used_blocks = used_blocks;
1051
1052	ret = ubi_attach_fastmap(ubi, ai, fm);
1053	if (ret) {
1054		if (ret > 0)
1055			ret = UBI_BAD_FASTMAP;
1056		goto free_hdr;
1057	}
1058
1059	for (i = 0; i < used_blocks; i++) {
1060		struct ubi_wl_entry *e;
1061
1062		e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1063		if (!e) {
1064			while (i--)
1065				kmem_cache_free(ubi_wl_entry_slab, fm->e[i]);
1066
1067			ret = -ENOMEM;
1068			goto free_hdr;
1069		}
1070
1071		e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
1072		e->ec = be32_to_cpu(fmsb2->block_ec[i]);
1073		fm->e[i] = e;
1074	}
1075
1076	ubi->fm = fm;
1077	ubi->fm_pool.max_size = ubi->fm->max_pool_size;
1078	ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
1079	ubi_msg(ubi, "attached by fastmap");
1080	ubi_msg(ubi, "fastmap pool size: %d", ubi->fm_pool.max_size);
1081	ubi_msg(ubi, "fastmap WL pool size: %d",
1082		ubi->fm_wl_pool.max_size);
1083	ubi->fm_disabled = 0;
1084	ubi->fast_attach = 1;
1085
1086	ubi_free_vid_buf(vb);
1087	kfree(ech);
1088out:
1089	up_write(&ubi->fm_protect);
1090	if (ret == UBI_BAD_FASTMAP)
1091		ubi_err(ubi, "Attach by fastmap failed, doing a full scan!");
1092	return ret;
1093
1094free_hdr:
1095	ubi_free_vid_buf(vb);
1096	kfree(ech);
1097free_fm_sb:
1098	kfree(fmsb);
1099	kfree(fm);
1100	goto out;
1101}
1102
1103int ubi_fastmap_init_checkmap(struct ubi_volume *vol, int leb_count)
1104{
1105	struct ubi_device *ubi = vol->ubi;
1106
1107	if (!ubi->fast_attach)
1108		return 0;
1109
1110	vol->checkmap = bitmap_zalloc(leb_count, GFP_KERNEL);
1111	if (!vol->checkmap)
1112		return -ENOMEM;
1113
1114	return 0;
1115}
1116
1117void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol)
1118{
1119	bitmap_free(vol->checkmap);
1120}
1121
1122/**
1123 * ubi_write_fastmap - writes a fastmap.
1124 * @ubi: UBI device object
1125 * @new_fm: the to be written fastmap
1126 *
1127 * Returns 0 on success, < 0 indicates an internal error.
1128 */
1129static int ubi_write_fastmap(struct ubi_device *ubi,
1130			     struct ubi_fastmap_layout *new_fm)
1131{
1132	size_t fm_pos = 0;
1133	void *fm_raw;
1134	struct ubi_fm_sb *fmsb;
1135	struct ubi_fm_hdr *fmh;
1136	struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
1137	struct ubi_fm_ec *fec;
1138	struct ubi_fm_volhdr *fvh;
1139	struct ubi_fm_eba *feba;
1140	struct ubi_wl_entry *wl_e;
1141	struct ubi_volume *vol;
1142	struct ubi_vid_io_buf *avbuf, *dvbuf;
1143	struct ubi_vid_hdr *avhdr, *dvhdr;
1144	struct ubi_work *ubi_wrk;
1145	struct rb_node *tmp_rb;
1146	int ret, i, j, free_peb_count, used_peb_count, vol_count;
1147	int scrub_peb_count, erase_peb_count;
1148	unsigned long *seen_pebs;
1149
1150	fm_raw = ubi->fm_buf;
1151	memset(ubi->fm_buf, 0, ubi->fm_size);
1152
1153	avbuf = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
1154	if (!avbuf) {
1155		ret = -ENOMEM;
1156		goto out;
1157	}
1158
1159	dvbuf = new_fm_vbuf(ubi, UBI_FM_DATA_VOLUME_ID);
1160	if (!dvbuf) {
1161		ret = -ENOMEM;
1162		goto out_free_avbuf;
1163	}
1164
1165	avhdr = ubi_get_vid_hdr(avbuf);
1166	dvhdr = ubi_get_vid_hdr(dvbuf);
1167
1168	seen_pebs = init_seen(ubi);
1169	if (IS_ERR(seen_pebs)) {
1170		ret = PTR_ERR(seen_pebs);
1171		goto out_free_dvbuf;
1172	}
1173
1174	spin_lock(&ubi->volumes_lock);
1175	spin_lock(&ubi->wl_lock);
1176
1177	fmsb = (struct ubi_fm_sb *)fm_raw;
1178	fm_pos += sizeof(*fmsb);
1179	ubi_assert(fm_pos <= ubi->fm_size);
1180
1181	fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
1182	fm_pos += sizeof(*fmh);
1183	ubi_assert(fm_pos <= ubi->fm_size);
1184
1185	fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
1186	fmsb->version = UBI_FM_FMT_VERSION;
1187	fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
1188	/* the max sqnum will be filled in while *reading* the fastmap */
1189	fmsb->sqnum = 0;
1190
1191	fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
1192	free_peb_count = 0;
1193	used_peb_count = 0;
1194	scrub_peb_count = 0;
1195	erase_peb_count = 0;
1196	vol_count = 0;
1197
1198	fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1199	fm_pos += sizeof(*fmpl);
1200	fmpl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1201	fmpl->size = cpu_to_be16(ubi->fm_pool.size);
1202	fmpl->max_size = cpu_to_be16(ubi->fm_pool.max_size);
1203
1204	for (i = 0; i < ubi->fm_pool.size; i++) {
1205		fmpl->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
1206		set_seen(ubi, ubi->fm_pool.pebs[i], seen_pebs);
1207	}
1208
1209	fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1210	fm_pos += sizeof(*fmpl_wl);
1211	fmpl_wl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1212	fmpl_wl->size = cpu_to_be16(ubi->fm_wl_pool.size);
1213	fmpl_wl->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
1214
1215	for (i = 0; i < ubi->fm_wl_pool.size; i++) {
1216		fmpl_wl->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
1217		set_seen(ubi, ubi->fm_wl_pool.pebs[i], seen_pebs);
1218	}
1219
1220	ubi_for_each_free_peb(ubi, wl_e, tmp_rb) {
1221		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1222
1223		fec->pnum = cpu_to_be32(wl_e->pnum);
1224		set_seen(ubi, wl_e->pnum, seen_pebs);
1225		fec->ec = cpu_to_be32(wl_e->ec);
1226
1227		free_peb_count++;
1228		fm_pos += sizeof(*fec);
1229		ubi_assert(fm_pos <= ubi->fm_size);
1230	}
1231	fmh->free_peb_count = cpu_to_be32(free_peb_count);
1232
1233	ubi_for_each_used_peb(ubi, wl_e, tmp_rb) {
1234		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1235
1236		fec->pnum = cpu_to_be32(wl_e->pnum);
1237		set_seen(ubi, wl_e->pnum, seen_pebs);
1238		fec->ec = cpu_to_be32(wl_e->ec);
1239
1240		used_peb_count++;
1241		fm_pos += sizeof(*fec);
1242		ubi_assert(fm_pos <= ubi->fm_size);
1243	}
1244
1245	ubi_for_each_protected_peb(ubi, i, wl_e) {
1246		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1247
1248		fec->pnum = cpu_to_be32(wl_e->pnum);
1249		set_seen(ubi, wl_e->pnum, seen_pebs);
1250		fec->ec = cpu_to_be32(wl_e->ec);
1251
1252		used_peb_count++;
1253		fm_pos += sizeof(*fec);
1254		ubi_assert(fm_pos <= ubi->fm_size);
1255	}
1256	fmh->used_peb_count = cpu_to_be32(used_peb_count);
1257
1258	ubi_for_each_scrub_peb(ubi, wl_e, tmp_rb) {
1259		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1260
1261		fec->pnum = cpu_to_be32(wl_e->pnum);
1262		set_seen(ubi, wl_e->pnum, seen_pebs);
1263		fec->ec = cpu_to_be32(wl_e->ec);
1264
1265		scrub_peb_count++;
1266		fm_pos += sizeof(*fec);
1267		ubi_assert(fm_pos <= ubi->fm_size);
1268	}
1269	fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
1270
1271
1272	list_for_each_entry(ubi_wrk, &ubi->works, list) {
1273		if (ubi_is_erase_work(ubi_wrk)) {
1274			wl_e = ubi_wrk->e;
1275			ubi_assert(wl_e);
1276
1277			fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1278
1279			fec->pnum = cpu_to_be32(wl_e->pnum);
1280			set_seen(ubi, wl_e->pnum, seen_pebs);
1281			fec->ec = cpu_to_be32(wl_e->ec);
1282
1283			erase_peb_count++;
1284			fm_pos += sizeof(*fec);
1285			ubi_assert(fm_pos <= ubi->fm_size);
1286		}
1287	}
1288	fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
1289
1290	for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
1291		vol = ubi->volumes[i];
1292
1293		if (!vol)
1294			continue;
1295
1296		vol_count++;
1297
1298		fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
1299		fm_pos += sizeof(*fvh);
1300		ubi_assert(fm_pos <= ubi->fm_size);
1301
1302		fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
1303		fvh->vol_id = cpu_to_be32(vol->vol_id);
1304		fvh->vol_type = vol->vol_type;
1305		fvh->used_ebs = cpu_to_be32(vol->used_ebs);
1306		fvh->data_pad = cpu_to_be32(vol->data_pad);
1307		fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
1308
1309		ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
1310			vol->vol_type == UBI_STATIC_VOLUME);
1311
1312		feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
1313		fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
1314		ubi_assert(fm_pos <= ubi->fm_size);
1315
1316		for (j = 0; j < vol->reserved_pebs; j++) {
1317			struct ubi_eba_leb_desc ldesc;
1318
1319			ubi_eba_get_ldesc(vol, j, &ldesc);
1320			feba->pnum[j] = cpu_to_be32(ldesc.pnum);
1321		}
1322
1323		feba->reserved_pebs = cpu_to_be32(j);
1324		feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
1325	}
1326	fmh->vol_count = cpu_to_be32(vol_count);
1327	fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
1328
1329	avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1330	avhdr->lnum = 0;
1331
1332	spin_unlock(&ubi->wl_lock);
1333	spin_unlock(&ubi->volumes_lock);
1334
1335	dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
1336	ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avbuf);
1337	if (ret) {
1338		ubi_err(ubi, "unable to write vid_hdr to fastmap SB!");
1339		goto out_free_seen;
1340	}
1341
1342	for (i = 0; i < new_fm->used_blocks; i++) {
1343		fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
1344		set_seen(ubi, new_fm->e[i]->pnum, seen_pebs);
1345		fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
1346	}
1347
1348	fmsb->data_crc = 0;
1349	fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
1350					   ubi->fm_size));
1351
1352	for (i = 1; i < new_fm->used_blocks; i++) {
1353		dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1354		dvhdr->lnum = cpu_to_be32(i);
1355		dbg_bld("writing fastmap data to PEB %i sqnum %llu",
1356			new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
1357		ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvbuf);
1358		if (ret) {
1359			ubi_err(ubi, "unable to write vid_hdr to PEB %i!",
1360				new_fm->e[i]->pnum);
1361			goto out_free_seen;
1362		}
1363	}
1364
1365	for (i = 0; i < new_fm->used_blocks; i++) {
1366		ret = ubi_io_write_data(ubi, fm_raw + (i * ubi->leb_size),
1367					new_fm->e[i]->pnum, 0, ubi->leb_size);
1368		if (ret) {
1369			ubi_err(ubi, "unable to write fastmap to PEB %i!",
1370				new_fm->e[i]->pnum);
1371			goto out_free_seen;
1372		}
1373	}
1374
1375	ubi_assert(new_fm);
1376	ubi->fm = new_fm;
1377
1378	ret = self_check_seen(ubi, seen_pebs);
1379	dbg_bld("fastmap written!");
1380
1381out_free_seen:
1382	free_seen(seen_pebs);
1383out_free_dvbuf:
1384	ubi_free_vid_buf(dvbuf);
1385out_free_avbuf:
1386	ubi_free_vid_buf(avbuf);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1387
 
 
 
 
 
 
1388out:
 
1389	return ret;
1390}
1391
1392/**
1393 * invalidate_fastmap - destroys a fastmap.
1394 * @ubi: UBI device object
1395 *
1396 * This function ensures that upon next UBI attach a full scan
1397 * is issued. We need this if UBI is about to write a new fastmap
1398 * but is unable to do so. In this case we have two options:
1399 * a) Make sure that the current fastmap will not be usued upon
1400 * attach time and contine or b) fall back to RO mode to have the
1401 * current fastmap in a valid state.
1402 * Returns 0 on success, < 0 indicates an internal error.
1403 */
1404static int invalidate_fastmap(struct ubi_device *ubi)
1405{
1406	int ret;
1407	struct ubi_fastmap_layout *fm;
1408	struct ubi_wl_entry *e;
1409	struct ubi_vid_io_buf *vb = NULL;
1410	struct ubi_vid_hdr *vh;
1411
1412	if (!ubi->fm)
1413		return 0;
1414
1415	ubi->fm = NULL;
1416
1417	ret = -ENOMEM;
1418	fm = kzalloc(sizeof(*fm), GFP_NOFS);
1419	if (!fm)
1420		goto out;
1421
1422	vb = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
1423	if (!vb)
1424		goto out_free_fm;
1425
1426	vh = ubi_get_vid_hdr(vb);
1427
1428	ret = -ENOSPC;
1429	e = ubi_wl_get_fm_peb(ubi, 1);
1430	if (!e)
1431		goto out_free_fm;
1432
1433	/*
1434	 * Create fake fastmap such that UBI will fall back
1435	 * to scanning mode.
1436	 */
1437	vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1438	ret = ubi_io_write_vid_hdr(ubi, e->pnum, vb);
1439	if (ret < 0) {
1440		ubi_wl_put_fm_peb(ubi, e, 0, 0);
1441		goto out_free_fm;
1442	}
1443
1444	fm->used_blocks = 1;
1445	fm->e[0] = e;
1446
1447	ubi->fm = fm;
1448
1449out:
1450	ubi_free_vid_buf(vb);
1451	return ret;
1452
1453out_free_fm:
1454	kfree(fm);
1455	goto out;
1456}
1457
1458/**
1459 * return_fm_pebs - returns all PEBs used by a fastmap back to the
1460 * WL sub-system.
1461 * @ubi: UBI device object
1462 * @fm: fastmap layout object
1463 */
1464static void return_fm_pebs(struct ubi_device *ubi,
1465			   struct ubi_fastmap_layout *fm)
1466{
1467	int i;
1468
1469	if (!fm)
1470		return;
1471
1472	for (i = 0; i < fm->used_blocks; i++) {
1473		if (fm->e[i]) {
1474			ubi_wl_put_fm_peb(ubi, fm->e[i], i,
1475					  fm->to_be_tortured[i]);
1476			fm->e[i] = NULL;
1477		}
1478	}
1479}
1480
1481/**
1482 * ubi_update_fastmap - will be called by UBI if a volume changes or
1483 * a fastmap pool becomes full.
1484 * @ubi: UBI device object
1485 *
1486 * Returns 0 on success, < 0 indicates an internal error.
1487 */
1488int ubi_update_fastmap(struct ubi_device *ubi)
1489{
1490	int ret, i, j;
1491	struct ubi_fastmap_layout *new_fm, *old_fm;
1492	struct ubi_wl_entry *tmp_e;
1493
1494	ubi_refill_pools_and_lock(ubi);
 
 
 
 
1495
1496	if (ubi->ro_mode || ubi->fm_disabled) {
1497		up_write(&ubi->fm_eba_sem);
1498		up_write(&ubi->work_sem);
1499		up_write(&ubi->fm_protect);
1500		return 0;
1501	}
1502
1503	new_fm = kzalloc(sizeof(*new_fm), GFP_NOFS);
 
 
 
 
 
 
 
 
1504	if (!new_fm) {
1505		up_write(&ubi->fm_eba_sem);
1506		up_write(&ubi->work_sem);
1507		up_write(&ubi->fm_protect);
1508		return -ENOMEM;
1509	}
1510
1511	new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1512	old_fm = ubi->fm;
1513	ubi->fm = NULL;
1514
1515	if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1516		ubi_err(ubi, "fastmap too large");
1517		ret = -ENOSPC;
1518		goto err;
1519	}
1520
1521	for (i = 1; i < new_fm->used_blocks; i++) {
1522		spin_lock(&ubi->wl_lock);
1523		tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1524		spin_unlock(&ubi->wl_lock);
1525
1526		if (!tmp_e) {
1527			if (old_fm && old_fm->e[i]) {
1528				ret = ubi_sync_erase(ubi, old_fm->e[i], 0);
1529				if (ret < 0) {
1530					ubi_err(ubi, "could not erase old fastmap PEB");
1531
1532					for (j = 1; j < i; j++) {
1533						ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1534								  j, 0);
1535						new_fm->e[j] = NULL;
1536					}
1537					goto err;
1538				}
1539				new_fm->e[i] = old_fm->e[i];
1540				old_fm->e[i] = NULL;
1541			} else {
1542				ubi_err(ubi, "could not get any free erase block");
1543
1544				for (j = 1; j < i; j++) {
1545					ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1546					new_fm->e[j] = NULL;
1547				}
1548
1549				ret = -ENOSPC;
1550				goto err;
1551			}
1552		} else {
1553			new_fm->e[i] = tmp_e;
1554
1555			if (old_fm && old_fm->e[i]) {
1556				ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1557						  old_fm->to_be_tortured[i]);
1558				old_fm->e[i] = NULL;
1559			}
1560		}
1561	}
1562
1563	/* Old fastmap is larger than the new one */
1564	if (old_fm && new_fm->used_blocks < old_fm->used_blocks) {
1565		for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) {
1566			ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1567					  old_fm->to_be_tortured[i]);
1568			old_fm->e[i] = NULL;
1569		}
1570	}
1571
1572	spin_lock(&ubi->wl_lock);
1573	tmp_e = ubi->fm_anchor;
1574	ubi->fm_anchor = NULL;
1575	spin_unlock(&ubi->wl_lock);
1576
1577	if (old_fm) {
1578		/* no fresh anchor PEB was found, reuse the old one */
1579		if (!tmp_e) {
1580			ret = ubi_sync_erase(ubi, old_fm->e[0], 0);
1581			if (ret < 0) {
1582				ubi_err(ubi, "could not erase old anchor PEB");
1583
1584				for (i = 1; i < new_fm->used_blocks; i++) {
1585					ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1586							  i, 0);
1587					new_fm->e[i] = NULL;
1588				}
1589				goto err;
1590			}
1591			new_fm->e[0] = old_fm->e[0];
 
1592			old_fm->e[0] = NULL;
1593		} else {
1594			/* we've got a new anchor PEB, return the old one */
1595			ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1596					  old_fm->to_be_tortured[0]);
1597			new_fm->e[0] = tmp_e;
1598			old_fm->e[0] = NULL;
1599		}
1600	} else {
1601		if (!tmp_e) {
1602			ubi_err(ubi, "could not find any anchor PEB");
1603
1604			for (i = 1; i < new_fm->used_blocks; i++) {
1605				ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1606				new_fm->e[i] = NULL;
1607			}
1608
1609			ret = -ENOSPC;
1610			goto err;
1611		}
1612		new_fm->e[0] = tmp_e;
1613	}
1614
1615	ret = ubi_write_fastmap(ubi, new_fm);
1616
1617	if (ret)
1618		goto err;
1619
1620out_unlock:
1621	up_write(&ubi->fm_eba_sem);
1622	up_write(&ubi->work_sem);
1623	up_write(&ubi->fm_protect);
1624	kfree(old_fm);
1625
1626	ubi_ensure_anchor_pebs(ubi);
1627
1628	return ret;
1629
1630err:
1631	ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret);
1632
1633	ret = invalidate_fastmap(ubi);
1634	if (ret < 0) {
1635		ubi_err(ubi, "Unable to invalidate current fastmap!");
1636		ubi_ro_mode(ubi);
1637	} else {
1638		return_fm_pebs(ubi, old_fm);
1639		return_fm_pebs(ubi, new_fm);
1640		ret = 0;
1641	}
1642
1643	kfree(new_fm);
1644	goto out_unlock;
1645}
v4.17
 
   1/*
   2 * Copyright (c) 2012 Linutronix GmbH
   3 * Copyright (c) 2014 sigma star gmbh
   4 * Author: Richard Weinberger <richard@nod.at>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; version 2.
   9 *
  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.
  14 *
  15 */
  16
  17#include <linux/crc32.h>
  18#include <linux/bitmap.h>
  19#include "ubi.h"
  20
  21/**
  22 * init_seen - allocate memory for used for debugging.
  23 * @ubi: UBI device description object
  24 */
  25static inline unsigned long *init_seen(struct ubi_device *ubi)
  26{
  27	unsigned long *ret;
  28
  29	if (!ubi_dbg_chk_fastmap(ubi))
  30		return NULL;
  31
  32	ret = kcalloc(BITS_TO_LONGS(ubi->peb_count), sizeof(unsigned long),
  33		      GFP_KERNEL);
  34	if (!ret)
  35		return ERR_PTR(-ENOMEM);
  36
  37	return ret;
  38}
  39
  40/**
  41 * free_seen - free the seen logic integer array.
  42 * @seen: integer array of @ubi->peb_count size
  43 */
  44static inline void free_seen(unsigned long *seen)
  45{
  46	kfree(seen);
  47}
  48
  49/**
  50 * set_seen - mark a PEB as seen.
  51 * @ubi: UBI device description object
  52 * @pnum: The PEB to be makred as seen
  53 * @seen: integer array of @ubi->peb_count size
  54 */
  55static inline void set_seen(struct ubi_device *ubi, int pnum, unsigned long *seen)
  56{
  57	if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  58		return;
  59
  60	set_bit(pnum, seen);
  61}
  62
  63/**
  64 * self_check_seen - check whether all PEB have been seen by fastmap.
  65 * @ubi: UBI device description object
  66 * @seen: integer array of @ubi->peb_count size
  67 */
  68static int self_check_seen(struct ubi_device *ubi, unsigned long *seen)
  69{
  70	int pnum, ret = 0;
  71
  72	if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  73		return 0;
  74
  75	for (pnum = 0; pnum < ubi->peb_count; pnum++) {
  76		if (test_bit(pnum, seen) && ubi->lookuptbl[pnum]) {
  77			ubi_err(ubi, "self-check failed for PEB %d, fastmap didn't see it", pnum);
  78			ret = -EINVAL;
  79		}
  80	}
  81
  82	return ret;
  83}
  84
  85/**
  86 * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
  87 * @ubi: UBI device description object
  88 */
  89size_t ubi_calc_fm_size(struct ubi_device *ubi)
  90{
  91	size_t size;
  92
  93	size = sizeof(struct ubi_fm_sb) +
  94		sizeof(struct ubi_fm_hdr) +
  95		sizeof(struct ubi_fm_scan_pool) +
  96		sizeof(struct ubi_fm_scan_pool) +
  97		(ubi->peb_count * sizeof(struct ubi_fm_ec)) +
  98		(sizeof(struct ubi_fm_eba) +
  99		(ubi->peb_count * sizeof(__be32))) +
 100		sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
 101	return roundup(size, ubi->leb_size);
 102}
 103
 104
 105/**
 106 * new_fm_vhdr - allocate a new volume header for fastmap usage.
 107 * @ubi: UBI device description object
 108 * @vol_id: the VID of the new header
 109 *
 110 * Returns a new struct ubi_vid_hdr on success.
 111 * NULL indicates out of memory.
 112 */
 113static struct ubi_vid_io_buf *new_fm_vbuf(struct ubi_device *ubi, int vol_id)
 114{
 115	struct ubi_vid_io_buf *new;
 116	struct ubi_vid_hdr *vh;
 117
 118	new = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
 119	if (!new)
 120		goto out;
 121
 122	vh = ubi_get_vid_hdr(new);
 123	vh->vol_type = UBI_VID_DYNAMIC;
 124	vh->vol_id = cpu_to_be32(vol_id);
 125
 126	/* UBI implementations without fastmap support have to delete the
 127	 * fastmap.
 128	 */
 129	vh->compat = UBI_COMPAT_DELETE;
 130
 131out:
 132	return new;
 133}
 134
 135/**
 136 * add_aeb - create and add a attach erase block to a given list.
 137 * @ai: UBI attach info object
 138 * @list: the target list
 139 * @pnum: PEB number of the new attach erase block
 140 * @ec: erease counter of the new LEB
 141 * @scrub: scrub this PEB after attaching
 142 *
 143 * Returns 0 on success, < 0 indicates an internal error.
 144 */
 145static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
 146		   int pnum, int ec, int scrub)
 147{
 148	struct ubi_ainf_peb *aeb;
 149
 150	aeb = ubi_alloc_aeb(ai, pnum, ec);
 151	if (!aeb)
 152		return -ENOMEM;
 153
 154	aeb->lnum = -1;
 155	aeb->scrub = scrub;
 156	aeb->copy_flag = aeb->sqnum = 0;
 157
 158	ai->ec_sum += aeb->ec;
 159	ai->ec_count++;
 160
 161	if (ai->max_ec < aeb->ec)
 162		ai->max_ec = aeb->ec;
 163
 164	if (ai->min_ec > aeb->ec)
 165		ai->min_ec = aeb->ec;
 166
 167	list_add_tail(&aeb->u.list, list);
 168
 169	return 0;
 170}
 171
 172/**
 173 * add_vol - create and add a new volume to ubi_attach_info.
 174 * @ai: ubi_attach_info object
 175 * @vol_id: VID of the new volume
 176 * @used_ebs: number of used EBS
 177 * @data_pad: data padding value of the new volume
 178 * @vol_type: volume type
 179 * @last_eb_bytes: number of bytes in the last LEB
 180 *
 181 * Returns the new struct ubi_ainf_volume on success.
 182 * NULL indicates an error.
 183 */
 184static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
 185				       int used_ebs, int data_pad, u8 vol_type,
 186				       int last_eb_bytes)
 187{
 188	struct ubi_ainf_volume *av;
 189
 190	av = ubi_add_av(ai, vol_id);
 191	if (IS_ERR(av))
 192		return av;
 193
 194	av->data_pad = data_pad;
 195	av->last_data_size = last_eb_bytes;
 196	av->compat = 0;
 197	av->vol_type = vol_type;
 198	if (av->vol_type == UBI_STATIC_VOLUME)
 199		av->used_ebs = used_ebs;
 200
 201	dbg_bld("found volume (ID %i)", vol_id);
 202	return av;
 203}
 204
 205/**
 206 * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
 207 * from it's original list.
 208 * @ai: ubi_attach_info object
 209 * @aeb: the to be assigned SEB
 210 * @av: target scan volume
 211 */
 212static void assign_aeb_to_av(struct ubi_attach_info *ai,
 213			     struct ubi_ainf_peb *aeb,
 214			     struct ubi_ainf_volume *av)
 215{
 216	struct ubi_ainf_peb *tmp_aeb;
 217	struct rb_node **p = &av->root.rb_node, *parent = NULL;
 218
 219	while (*p) {
 220		parent = *p;
 221
 222		tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 223		if (aeb->lnum != tmp_aeb->lnum) {
 224			if (aeb->lnum < tmp_aeb->lnum)
 225				p = &(*p)->rb_left;
 226			else
 227				p = &(*p)->rb_right;
 228
 229			continue;
 230		} else
 231			break;
 232	}
 233
 234	list_del(&aeb->u.list);
 235	av->leb_count++;
 236
 237	rb_link_node(&aeb->u.rb, parent, p);
 238	rb_insert_color(&aeb->u.rb, &av->root);
 239}
 240
 241/**
 242 * update_vol - inserts or updates a LEB which was found a pool.
 243 * @ubi: the UBI device object
 244 * @ai: attach info object
 245 * @av: the volume this LEB belongs to
 246 * @new_vh: the volume header derived from new_aeb
 247 * @new_aeb: the AEB to be examined
 248 *
 249 * Returns 0 on success, < 0 indicates an internal error.
 250 */
 251static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
 252		      struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
 253		      struct ubi_ainf_peb *new_aeb)
 254{
 255	struct rb_node **p = &av->root.rb_node, *parent = NULL;
 256	struct ubi_ainf_peb *aeb, *victim;
 257	int cmp_res;
 258
 259	while (*p) {
 260		parent = *p;
 261		aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 262
 263		if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
 264			if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
 265				p = &(*p)->rb_left;
 266			else
 267				p = &(*p)->rb_right;
 268
 269			continue;
 270		}
 271
 272		/* This case can happen if the fastmap gets written
 273		 * because of a volume change (creation, deletion, ..).
 274		 * Then a PEB can be within the persistent EBA and the pool.
 275		 */
 276		if (aeb->pnum == new_aeb->pnum) {
 277			ubi_assert(aeb->lnum == new_aeb->lnum);
 278			ubi_free_aeb(ai, new_aeb);
 279
 280			return 0;
 281		}
 282
 283		cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
 284		if (cmp_res < 0)
 285			return cmp_res;
 286
 287		/* new_aeb is newer */
 288		if (cmp_res & 1) {
 289			victim = ubi_alloc_aeb(ai, aeb->pnum, aeb->ec);
 290			if (!victim)
 291				return -ENOMEM;
 292
 293			list_add_tail(&victim->u.list, &ai->erase);
 294
 295			if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
 296				av->last_data_size =
 297					be32_to_cpu(new_vh->data_size);
 298
 299			dbg_bld("vol %i: AEB %i's PEB %i is the newer",
 300				av->vol_id, aeb->lnum, new_aeb->pnum);
 301
 302			aeb->ec = new_aeb->ec;
 303			aeb->pnum = new_aeb->pnum;
 304			aeb->copy_flag = new_vh->copy_flag;
 305			aeb->scrub = new_aeb->scrub;
 306			aeb->sqnum = new_aeb->sqnum;
 307			ubi_free_aeb(ai, new_aeb);
 308
 309		/* new_aeb is older */
 310		} else {
 311			dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
 312				av->vol_id, aeb->lnum, new_aeb->pnum);
 313			list_add_tail(&new_aeb->u.list, &ai->erase);
 314		}
 315
 316		return 0;
 317	}
 318	/* This LEB is new, let's add it to the volume */
 319
 320	if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
 321		av->highest_lnum = be32_to_cpu(new_vh->lnum);
 322		av->last_data_size = be32_to_cpu(new_vh->data_size);
 323	}
 324
 325	if (av->vol_type == UBI_STATIC_VOLUME)
 326		av->used_ebs = be32_to_cpu(new_vh->used_ebs);
 327
 328	av->leb_count++;
 329
 330	rb_link_node(&new_aeb->u.rb, parent, p);
 331	rb_insert_color(&new_aeb->u.rb, &av->root);
 332
 333	return 0;
 334}
 335
 336/**
 337 * process_pool_aeb - we found a non-empty PEB in a pool.
 338 * @ubi: UBI device object
 339 * @ai: attach info object
 340 * @new_vh: the volume header derived from new_aeb
 341 * @new_aeb: the AEB to be examined
 342 *
 343 * Returns 0 on success, < 0 indicates an internal error.
 344 */
 345static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 346			    struct ubi_vid_hdr *new_vh,
 347			    struct ubi_ainf_peb *new_aeb)
 348{
 349	int vol_id = be32_to_cpu(new_vh->vol_id);
 350	struct ubi_ainf_volume *av;
 351
 352	if (vol_id == UBI_FM_SB_VOLUME_ID || vol_id == UBI_FM_DATA_VOLUME_ID) {
 353		ubi_free_aeb(ai, new_aeb);
 354
 355		return 0;
 356	}
 357
 358	/* Find the volume this SEB belongs to */
 359	av = ubi_find_av(ai, vol_id);
 360	if (!av) {
 361		ubi_err(ubi, "orphaned volume in fastmap pool!");
 362		ubi_free_aeb(ai, new_aeb);
 363		return UBI_BAD_FASTMAP;
 364	}
 365
 366	ubi_assert(vol_id == av->vol_id);
 367
 368	return update_vol(ubi, ai, av, new_vh, new_aeb);
 369}
 370
 371/**
 372 * unmap_peb - unmap a PEB.
 373 * If fastmap detects a free PEB in the pool it has to check whether
 374 * this PEB has been unmapped after writing the fastmap.
 375 *
 376 * @ai: UBI attach info object
 377 * @pnum: The PEB to be unmapped
 378 */
 379static void unmap_peb(struct ubi_attach_info *ai, int pnum)
 380{
 381	struct ubi_ainf_volume *av;
 382	struct rb_node *node, *node2;
 383	struct ubi_ainf_peb *aeb;
 384
 385	ubi_rb_for_each_entry(node, av, &ai->volumes, rb) {
 386		ubi_rb_for_each_entry(node2, aeb, &av->root, u.rb) {
 387			if (aeb->pnum == pnum) {
 388				rb_erase(&aeb->u.rb, &av->root);
 389				av->leb_count--;
 390				ubi_free_aeb(ai, aeb);
 391				return;
 392			}
 393		}
 394	}
 395}
 396
 397/**
 398 * scan_pool - scans a pool for changed (no longer empty PEBs).
 399 * @ubi: UBI device object
 400 * @ai: attach info object
 401 * @pebs: an array of all PEB numbers in the to be scanned pool
 402 * @pool_size: size of the pool (number of entries in @pebs)
 403 * @max_sqnum: pointer to the maximal sequence number
 404 * @free: list of PEBs which are most likely free (and go into @ai->free)
 405 *
 406 * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
 407 * < 0 indicates an internal error.
 408 */
 409static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 410		     __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 411		     struct list_head *free)
 412{
 413	struct ubi_vid_io_buf *vb;
 414	struct ubi_vid_hdr *vh;
 415	struct ubi_ec_hdr *ech;
 416	struct ubi_ainf_peb *new_aeb;
 417	int i, pnum, err, ret = 0;
 418
 419	ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 420	if (!ech)
 421		return -ENOMEM;
 422
 423	vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
 424	if (!vb) {
 425		kfree(ech);
 426		return -ENOMEM;
 427	}
 428
 429	vh = ubi_get_vid_hdr(vb);
 430
 431	dbg_bld("scanning fastmap pool: size = %i", pool_size);
 432
 433	/*
 434	 * Now scan all PEBs in the pool to find changes which have been made
 435	 * after the creation of the fastmap
 436	 */
 437	for (i = 0; i < pool_size; i++) {
 438		int scrub = 0;
 439		int image_seq;
 440
 441		pnum = be32_to_cpu(pebs[i]);
 442
 443		if (ubi_io_is_bad(ubi, pnum)) {
 444			ubi_err(ubi, "bad PEB in fastmap pool!");
 445			ret = UBI_BAD_FASTMAP;
 446			goto out;
 447		}
 448
 449		err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 450		if (err && err != UBI_IO_BITFLIPS) {
 451			ubi_err(ubi, "unable to read EC header! PEB:%i err:%i",
 452				pnum, err);
 453			ret = err > 0 ? UBI_BAD_FASTMAP : err;
 454			goto out;
 455		} else if (err == UBI_IO_BITFLIPS)
 456			scrub = 1;
 457
 458		/*
 459		 * Older UBI implementations have image_seq set to zero, so
 460		 * we shouldn't fail if image_seq == 0.
 461		 */
 462		image_seq = be32_to_cpu(ech->image_seq);
 463
 464		if (image_seq && (image_seq != ubi->image_seq)) {
 465			ubi_err(ubi, "bad image seq: 0x%x, expected: 0x%x",
 466				be32_to_cpu(ech->image_seq), ubi->image_seq);
 467			ret = UBI_BAD_FASTMAP;
 468			goto out;
 469		}
 470
 471		err = ubi_io_read_vid_hdr(ubi, pnum, vb, 0);
 472		if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
 473			unsigned long long ec = be64_to_cpu(ech->ec);
 474			unmap_peb(ai, pnum);
 475			dbg_bld("Adding PEB to free: %i", pnum);
 476
 477			if (err == UBI_IO_FF_BITFLIPS)
 478				scrub = 1;
 479
 480			add_aeb(ai, free, pnum, ec, scrub);
 
 
 481			continue;
 482		} else if (err == 0 || err == UBI_IO_BITFLIPS) {
 483			dbg_bld("Found non empty PEB:%i in pool", pnum);
 484
 485			if (err == UBI_IO_BITFLIPS)
 486				scrub = 1;
 487
 488			new_aeb = ubi_alloc_aeb(ai, pnum, be64_to_cpu(ech->ec));
 489			if (!new_aeb) {
 490				ret = -ENOMEM;
 491				goto out;
 492			}
 493
 494			new_aeb->lnum = be32_to_cpu(vh->lnum);
 495			new_aeb->sqnum = be64_to_cpu(vh->sqnum);
 496			new_aeb->copy_flag = vh->copy_flag;
 497			new_aeb->scrub = scrub;
 498
 499			if (*max_sqnum < new_aeb->sqnum)
 500				*max_sqnum = new_aeb->sqnum;
 501
 502			err = process_pool_aeb(ubi, ai, vh, new_aeb);
 503			if (err) {
 504				ret = err > 0 ? UBI_BAD_FASTMAP : err;
 505				goto out;
 506			}
 507		} else {
 508			/* We are paranoid and fall back to scanning mode */
 509			ubi_err(ubi, "fastmap pool PEBs contains damaged PEBs!");
 510			ret = err > 0 ? UBI_BAD_FASTMAP : err;
 511			goto out;
 512		}
 513
 514	}
 515
 516out:
 517	ubi_free_vid_buf(vb);
 518	kfree(ech);
 519	return ret;
 520}
 521
 522/**
 523 * count_fastmap_pebs - Counts the PEBs found by fastmap.
 524 * @ai: The UBI attach info object
 525 */
 526static int count_fastmap_pebs(struct ubi_attach_info *ai)
 527{
 528	struct ubi_ainf_peb *aeb;
 529	struct ubi_ainf_volume *av;
 530	struct rb_node *rb1, *rb2;
 531	int n = 0;
 532
 533	list_for_each_entry(aeb, &ai->erase, u.list)
 534		n++;
 535
 536	list_for_each_entry(aeb, &ai->free, u.list)
 537		n++;
 538
 539	ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
 540		ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
 541			n++;
 542
 543	return n;
 544}
 545
 546/**
 547 * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
 548 * @ubi: UBI device object
 549 * @ai: UBI attach info object
 550 * @fm: the fastmap to be attached
 551 *
 552 * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
 553 * < 0 indicates an internal error.
 554 */
 555static int ubi_attach_fastmap(struct ubi_device *ubi,
 556			      struct ubi_attach_info *ai,
 557			      struct ubi_fastmap_layout *fm)
 558{
 559	struct list_head used, free;
 560	struct ubi_ainf_volume *av;
 561	struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
 562	struct ubi_fm_sb *fmsb;
 563	struct ubi_fm_hdr *fmhdr;
 564	struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
 565	struct ubi_fm_ec *fmec;
 566	struct ubi_fm_volhdr *fmvhdr;
 567	struct ubi_fm_eba *fm_eba;
 568	int ret, i, j, pool_size, wl_pool_size;
 569	size_t fm_pos = 0, fm_size = ubi->fm_size;
 570	unsigned long long max_sqnum = 0;
 571	void *fm_raw = ubi->fm_buf;
 572
 573	INIT_LIST_HEAD(&used);
 574	INIT_LIST_HEAD(&free);
 575	ai->min_ec = UBI_MAX_ERASECOUNTER;
 576
 577	fmsb = (struct ubi_fm_sb *)(fm_raw);
 578	ai->max_sqnum = fmsb->sqnum;
 579	fm_pos += sizeof(struct ubi_fm_sb);
 580	if (fm_pos >= fm_size)
 581		goto fail_bad;
 582
 583	fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
 584	fm_pos += sizeof(*fmhdr);
 585	if (fm_pos >= fm_size)
 586		goto fail_bad;
 587
 588	if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
 589		ubi_err(ubi, "bad fastmap header magic: 0x%x, expected: 0x%x",
 590			be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
 591		goto fail_bad;
 592	}
 593
 594	fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 595	fm_pos += sizeof(*fmpl);
 596	if (fm_pos >= fm_size)
 597		goto fail_bad;
 598	if (be32_to_cpu(fmpl->magic) != UBI_FM_POOL_MAGIC) {
 599		ubi_err(ubi, "bad fastmap pool magic: 0x%x, expected: 0x%x",
 600			be32_to_cpu(fmpl->magic), UBI_FM_POOL_MAGIC);
 601		goto fail_bad;
 602	}
 603
 604	fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 605	fm_pos += sizeof(*fmpl_wl);
 606	if (fm_pos >= fm_size)
 607		goto fail_bad;
 608	if (be32_to_cpu(fmpl_wl->magic) != UBI_FM_POOL_MAGIC) {
 609		ubi_err(ubi, "bad fastmap WL pool magic: 0x%x, expected: 0x%x",
 610			be32_to_cpu(fmpl_wl->magic), UBI_FM_POOL_MAGIC);
 611		goto fail_bad;
 612	}
 613
 614	pool_size = be16_to_cpu(fmpl->size);
 615	wl_pool_size = be16_to_cpu(fmpl_wl->size);
 616	fm->max_pool_size = be16_to_cpu(fmpl->max_size);
 617	fm->max_wl_pool_size = be16_to_cpu(fmpl_wl->max_size);
 618
 619	if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
 620		ubi_err(ubi, "bad pool size: %i", pool_size);
 621		goto fail_bad;
 622	}
 623
 624	if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
 625		ubi_err(ubi, "bad WL pool size: %i", wl_pool_size);
 626		goto fail_bad;
 627	}
 628
 629
 630	if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
 631	    fm->max_pool_size < 0) {
 632		ubi_err(ubi, "bad maximal pool size: %i", fm->max_pool_size);
 633		goto fail_bad;
 634	}
 635
 636	if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
 637	    fm->max_wl_pool_size < 0) {
 638		ubi_err(ubi, "bad maximal WL pool size: %i",
 639			fm->max_wl_pool_size);
 640		goto fail_bad;
 641	}
 642
 643	/* read EC values from free list */
 644	for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
 645		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 646		fm_pos += sizeof(*fmec);
 647		if (fm_pos >= fm_size)
 648			goto fail_bad;
 649
 650		add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
 651			be32_to_cpu(fmec->ec), 0);
 
 
 652	}
 653
 654	/* read EC values from used list */
 655	for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
 656		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 657		fm_pos += sizeof(*fmec);
 658		if (fm_pos >= fm_size)
 659			goto fail_bad;
 660
 661		add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 662			be32_to_cpu(fmec->ec), 0);
 
 
 663	}
 664
 665	/* read EC values from scrub list */
 666	for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
 667		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 668		fm_pos += sizeof(*fmec);
 669		if (fm_pos >= fm_size)
 670			goto fail_bad;
 671
 672		add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 673			be32_to_cpu(fmec->ec), 1);
 
 
 674	}
 675
 676	/* read EC values from erase list */
 677	for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
 678		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 679		fm_pos += sizeof(*fmec);
 680		if (fm_pos >= fm_size)
 681			goto fail_bad;
 682
 683		add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
 684			be32_to_cpu(fmec->ec), 1);
 
 
 685	}
 686
 687	ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
 688	ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
 689
 690	/* Iterate over all volumes and read their EBA table */
 691	for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
 692		fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
 693		fm_pos += sizeof(*fmvhdr);
 694		if (fm_pos >= fm_size)
 695			goto fail_bad;
 696
 697		if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
 698			ubi_err(ubi, "bad fastmap vol header magic: 0x%x, expected: 0x%x",
 699				be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
 700			goto fail_bad;
 701		}
 702
 703		av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
 704			     be32_to_cpu(fmvhdr->used_ebs),
 705			     be32_to_cpu(fmvhdr->data_pad),
 706			     fmvhdr->vol_type,
 707			     be32_to_cpu(fmvhdr->last_eb_bytes));
 708
 709		if (IS_ERR(av)) {
 710			if (PTR_ERR(av) == -EEXIST)
 711				ubi_err(ubi, "volume (ID %i) already exists",
 712					fmvhdr->vol_id);
 713
 714			goto fail_bad;
 715		}
 716
 717		ai->vols_found++;
 718		if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
 719			ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
 720
 721		fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
 722		fm_pos += sizeof(*fm_eba);
 723		fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
 724		if (fm_pos >= fm_size)
 725			goto fail_bad;
 726
 727		if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
 728			ubi_err(ubi, "bad fastmap EBA header magic: 0x%x, expected: 0x%x",
 729				be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
 730			goto fail_bad;
 731		}
 732
 733		for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
 734			int pnum = be32_to_cpu(fm_eba->pnum[j]);
 735
 736			if (pnum < 0)
 737				continue;
 738
 739			aeb = NULL;
 740			list_for_each_entry(tmp_aeb, &used, u.list) {
 741				if (tmp_aeb->pnum == pnum) {
 742					aeb = tmp_aeb;
 743					break;
 744				}
 745			}
 746
 747			if (!aeb) {
 748				ubi_err(ubi, "PEB %i is in EBA but not in used list", pnum);
 749				goto fail_bad;
 750			}
 751
 752			aeb->lnum = j;
 753
 754			if (av->highest_lnum <= aeb->lnum)
 755				av->highest_lnum = aeb->lnum;
 756
 757			assign_aeb_to_av(ai, aeb, av);
 758
 759			dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
 760				aeb->pnum, aeb->lnum, av->vol_id);
 761		}
 762	}
 763
 764	ret = scan_pool(ubi, ai, fmpl->pebs, pool_size, &max_sqnum, &free);
 765	if (ret)
 766		goto fail;
 767
 768	ret = scan_pool(ubi, ai, fmpl_wl->pebs, wl_pool_size, &max_sqnum, &free);
 769	if (ret)
 770		goto fail;
 771
 772	if (max_sqnum > ai->max_sqnum)
 773		ai->max_sqnum = max_sqnum;
 774
 775	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list)
 776		list_move_tail(&tmp_aeb->u.list, &ai->free);
 777
 778	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list)
 779		list_move_tail(&tmp_aeb->u.list, &ai->erase);
 780
 781	ubi_assert(list_empty(&free));
 782
 783	/*
 784	 * If fastmap is leaking PEBs (must not happen), raise a
 785	 * fat warning and fall back to scanning mode.
 786	 * We do this here because in ubi_wl_init() it's too late
 787	 * and we cannot fall back to scanning.
 788	 */
 789	if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
 790		    ai->bad_peb_count - fm->used_blocks))
 791		goto fail_bad;
 792
 793	return 0;
 794
 795fail_bad:
 796	ret = UBI_BAD_FASTMAP;
 797fail:
 798	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) {
 799		list_del(&tmp_aeb->u.list);
 800		ubi_free_aeb(ai, tmp_aeb);
 801	}
 802	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) {
 803		list_del(&tmp_aeb->u.list);
 804		ubi_free_aeb(ai, tmp_aeb);
 805	}
 806
 807	return ret;
 808}
 809
 810/**
 811 * find_fm_anchor - find the most recent Fastmap superblock (anchor)
 812 * @ai: UBI attach info to be filled
 813 */
 814static int find_fm_anchor(struct ubi_attach_info *ai)
 815{
 816	int ret = -1;
 817	struct ubi_ainf_peb *aeb;
 818	unsigned long long max_sqnum = 0;
 819
 820	list_for_each_entry(aeb, &ai->fastmap, u.list) {
 821		if (aeb->vol_id == UBI_FM_SB_VOLUME_ID && aeb->sqnum > max_sqnum) {
 822			max_sqnum = aeb->sqnum;
 823			ret = aeb->pnum;
 824		}
 825	}
 826
 827	return ret;
 828}
 829
 830static struct ubi_ainf_peb *clone_aeb(struct ubi_attach_info *ai,
 831				      struct ubi_ainf_peb *old)
 832{
 833	struct ubi_ainf_peb *new;
 834
 835	new = ubi_alloc_aeb(ai, old->pnum, old->ec);
 836	if (!new)
 837		return NULL;
 838
 839	new->vol_id = old->vol_id;
 840	new->sqnum = old->sqnum;
 841	new->lnum = old->lnum;
 842	new->scrub = old->scrub;
 843	new->copy_flag = old->copy_flag;
 844
 845	return new;
 846}
 847
 848/**
 849 * ubi_scan_fastmap - scan the fastmap.
 850 * @ubi: UBI device object
 851 * @ai: UBI attach info to be filled
 852 * @scan_ai: UBI attach info from the first 64 PEBs,
 853 *           used to find the most recent Fastmap data structure
 854 *
 855 * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
 856 * UBI_BAD_FASTMAP if one was found but is not usable.
 857 * < 0 indicates an internal error.
 858 */
 859int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 860		     struct ubi_attach_info *scan_ai)
 861{
 862	struct ubi_fm_sb *fmsb, *fmsb2;
 863	struct ubi_vid_io_buf *vb;
 864	struct ubi_vid_hdr *vh;
 865	struct ubi_ec_hdr *ech;
 866	struct ubi_fastmap_layout *fm;
 867	struct ubi_ainf_peb *aeb;
 868	int i, used_blocks, pnum, fm_anchor, ret = 0;
 869	size_t fm_size;
 870	__be32 crc, tmp_crc;
 871	unsigned long long sqnum = 0;
 872
 873	fm_anchor = find_fm_anchor(scan_ai);
 874	if (fm_anchor < 0)
 875		return UBI_NO_FASTMAP;
 876
 877	/* Copy all (possible) fastmap blocks into our new attach structure. */
 878	list_for_each_entry(aeb, &scan_ai->fastmap, u.list) {
 879		struct ubi_ainf_peb *new;
 880
 881		new = clone_aeb(ai, aeb);
 882		if (!new)
 883			return -ENOMEM;
 884
 885		list_add(&new->u.list, &ai->fastmap);
 886	}
 887
 888	down_write(&ubi->fm_protect);
 889	memset(ubi->fm_buf, 0, ubi->fm_size);
 890
 891	fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
 892	if (!fmsb) {
 893		ret = -ENOMEM;
 894		goto out;
 895	}
 896
 897	fm = kzalloc(sizeof(*fm), GFP_KERNEL);
 898	if (!fm) {
 899		ret = -ENOMEM;
 900		kfree(fmsb);
 901		goto out;
 902	}
 903
 904	ret = ubi_io_read_data(ubi, fmsb, fm_anchor, 0, sizeof(*fmsb));
 905	if (ret && ret != UBI_IO_BITFLIPS)
 906		goto free_fm_sb;
 907	else if (ret == UBI_IO_BITFLIPS)
 908		fm->to_be_tortured[0] = 1;
 909
 910	if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
 911		ubi_err(ubi, "bad super block magic: 0x%x, expected: 0x%x",
 912			be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
 913		ret = UBI_BAD_FASTMAP;
 914		goto free_fm_sb;
 915	}
 916
 917	if (fmsb->version != UBI_FM_FMT_VERSION) {
 918		ubi_err(ubi, "bad fastmap version: %i, expected: %i",
 919			fmsb->version, UBI_FM_FMT_VERSION);
 920		ret = UBI_BAD_FASTMAP;
 921		goto free_fm_sb;
 922	}
 923
 924	used_blocks = be32_to_cpu(fmsb->used_blocks);
 925	if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
 926		ubi_err(ubi, "number of fastmap blocks is invalid: %i",
 927			used_blocks);
 928		ret = UBI_BAD_FASTMAP;
 929		goto free_fm_sb;
 930	}
 931
 932	fm_size = ubi->leb_size * used_blocks;
 933	if (fm_size != ubi->fm_size) {
 934		ubi_err(ubi, "bad fastmap size: %zi, expected: %zi",
 935			fm_size, ubi->fm_size);
 936		ret = UBI_BAD_FASTMAP;
 937		goto free_fm_sb;
 938	}
 939
 940	ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 941	if (!ech) {
 942		ret = -ENOMEM;
 943		goto free_fm_sb;
 944	}
 945
 946	vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
 947	if (!vb) {
 948		ret = -ENOMEM;
 949		goto free_hdr;
 950	}
 951
 952	vh = ubi_get_vid_hdr(vb);
 953
 954	for (i = 0; i < used_blocks; i++) {
 955		int image_seq;
 956
 957		pnum = be32_to_cpu(fmsb->block_loc[i]);
 958
 959		if (ubi_io_is_bad(ubi, pnum)) {
 960			ret = UBI_BAD_FASTMAP;
 961			goto free_hdr;
 962		}
 963
 964		if (i == 0 && pnum != fm_anchor) {
 965			ubi_err(ubi, "Fastmap anchor PEB mismatch: PEB: %i vs. %i",
 966				pnum, fm_anchor);
 967			ret = UBI_BAD_FASTMAP;
 968			goto free_hdr;
 969		}
 970
 971		ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 972		if (ret && ret != UBI_IO_BITFLIPS) {
 973			ubi_err(ubi, "unable to read fastmap block# %i EC (PEB: %i)",
 974				i, pnum);
 975			if (ret > 0)
 976				ret = UBI_BAD_FASTMAP;
 977			goto free_hdr;
 978		} else if (ret == UBI_IO_BITFLIPS)
 979			fm->to_be_tortured[i] = 1;
 980
 981		image_seq = be32_to_cpu(ech->image_seq);
 982		if (!ubi->image_seq)
 983			ubi->image_seq = image_seq;
 984
 985		/*
 986		 * Older UBI implementations have image_seq set to zero, so
 987		 * we shouldn't fail if image_seq == 0.
 988		 */
 989		if (image_seq && (image_seq != ubi->image_seq)) {
 990			ubi_err(ubi, "wrong image seq:%d instead of %d",
 991				be32_to_cpu(ech->image_seq), ubi->image_seq);
 992			ret = UBI_BAD_FASTMAP;
 993			goto free_hdr;
 994		}
 995
 996		ret = ubi_io_read_vid_hdr(ubi, pnum, vb, 0);
 997		if (ret && ret != UBI_IO_BITFLIPS) {
 998			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i)",
 999				i, pnum);
1000			goto free_hdr;
1001		}
1002
1003		if (i == 0) {
1004			if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
1005				ubi_err(ubi, "bad fastmap anchor vol_id: 0x%x, expected: 0x%x",
1006					be32_to_cpu(vh->vol_id),
1007					UBI_FM_SB_VOLUME_ID);
1008				ret = UBI_BAD_FASTMAP;
1009				goto free_hdr;
1010			}
1011		} else {
1012			if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
1013				ubi_err(ubi, "bad fastmap data vol_id: 0x%x, expected: 0x%x",
1014					be32_to_cpu(vh->vol_id),
1015					UBI_FM_DATA_VOLUME_ID);
1016				ret = UBI_BAD_FASTMAP;
1017				goto free_hdr;
1018			}
1019		}
1020
1021		if (sqnum < be64_to_cpu(vh->sqnum))
1022			sqnum = be64_to_cpu(vh->sqnum);
1023
1024		ret = ubi_io_read_data(ubi, ubi->fm_buf + (ubi->leb_size * i),
1025				       pnum, 0, ubi->leb_size);
1026		if (ret && ret != UBI_IO_BITFLIPS) {
1027			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i, "
1028				"err: %i)", i, pnum, ret);
1029			goto free_hdr;
1030		}
1031	}
1032
1033	kfree(fmsb);
1034	fmsb = NULL;
1035
1036	fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
1037	tmp_crc = be32_to_cpu(fmsb2->data_crc);
1038	fmsb2->data_crc = 0;
1039	crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
1040	if (crc != tmp_crc) {
1041		ubi_err(ubi, "fastmap data CRC is invalid");
1042		ubi_err(ubi, "CRC should be: 0x%x, calc: 0x%x",
1043			tmp_crc, crc);
1044		ret = UBI_BAD_FASTMAP;
1045		goto free_hdr;
1046	}
1047
1048	fmsb2->sqnum = sqnum;
1049
1050	fm->used_blocks = used_blocks;
1051
1052	ret = ubi_attach_fastmap(ubi, ai, fm);
1053	if (ret) {
1054		if (ret > 0)
1055			ret = UBI_BAD_FASTMAP;
1056		goto free_hdr;
1057	}
1058
1059	for (i = 0; i < used_blocks; i++) {
1060		struct ubi_wl_entry *e;
1061
1062		e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1063		if (!e) {
1064			while (i--)
1065				kmem_cache_free(ubi_wl_entry_slab, fm->e[i]);
1066
1067			ret = -ENOMEM;
1068			goto free_hdr;
1069		}
1070
1071		e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
1072		e->ec = be32_to_cpu(fmsb2->block_ec[i]);
1073		fm->e[i] = e;
1074	}
1075
1076	ubi->fm = fm;
1077	ubi->fm_pool.max_size = ubi->fm->max_pool_size;
1078	ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
1079	ubi_msg(ubi, "attached by fastmap");
1080	ubi_msg(ubi, "fastmap pool size: %d", ubi->fm_pool.max_size);
1081	ubi_msg(ubi, "fastmap WL pool size: %d",
1082		ubi->fm_wl_pool.max_size);
1083	ubi->fm_disabled = 0;
1084	ubi->fast_attach = 1;
1085
1086	ubi_free_vid_buf(vb);
1087	kfree(ech);
1088out:
1089	up_write(&ubi->fm_protect);
1090	if (ret == UBI_BAD_FASTMAP)
1091		ubi_err(ubi, "Attach by fastmap failed, doing a full scan!");
1092	return ret;
1093
1094free_hdr:
1095	ubi_free_vid_buf(vb);
1096	kfree(ech);
1097free_fm_sb:
1098	kfree(fmsb);
1099	kfree(fm);
1100	goto out;
1101}
1102
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1103/**
1104 * ubi_write_fastmap - writes a fastmap.
1105 * @ubi: UBI device object
1106 * @new_fm: the to be written fastmap
1107 *
1108 * Returns 0 on success, < 0 indicates an internal error.
1109 */
1110static int ubi_write_fastmap(struct ubi_device *ubi,
1111			     struct ubi_fastmap_layout *new_fm)
1112{
1113	size_t fm_pos = 0;
1114	void *fm_raw;
1115	struct ubi_fm_sb *fmsb;
1116	struct ubi_fm_hdr *fmh;
1117	struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
1118	struct ubi_fm_ec *fec;
1119	struct ubi_fm_volhdr *fvh;
1120	struct ubi_fm_eba *feba;
1121	struct ubi_wl_entry *wl_e;
1122	struct ubi_volume *vol;
1123	struct ubi_vid_io_buf *avbuf, *dvbuf;
1124	struct ubi_vid_hdr *avhdr, *dvhdr;
1125	struct ubi_work *ubi_wrk;
1126	struct rb_node *tmp_rb;
1127	int ret, i, j, free_peb_count, used_peb_count, vol_count;
1128	int scrub_peb_count, erase_peb_count;
1129	unsigned long *seen_pebs = NULL;
1130
1131	fm_raw = ubi->fm_buf;
1132	memset(ubi->fm_buf, 0, ubi->fm_size);
1133
1134	avbuf = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
1135	if (!avbuf) {
1136		ret = -ENOMEM;
1137		goto out;
1138	}
1139
1140	dvbuf = new_fm_vbuf(ubi, UBI_FM_DATA_VOLUME_ID);
1141	if (!dvbuf) {
1142		ret = -ENOMEM;
1143		goto out_kfree;
1144	}
1145
1146	avhdr = ubi_get_vid_hdr(avbuf);
1147	dvhdr = ubi_get_vid_hdr(dvbuf);
1148
1149	seen_pebs = init_seen(ubi);
1150	if (IS_ERR(seen_pebs)) {
1151		ret = PTR_ERR(seen_pebs);
1152		goto out_kfree;
1153	}
1154
1155	spin_lock(&ubi->volumes_lock);
1156	spin_lock(&ubi->wl_lock);
1157
1158	fmsb = (struct ubi_fm_sb *)fm_raw;
1159	fm_pos += sizeof(*fmsb);
1160	ubi_assert(fm_pos <= ubi->fm_size);
1161
1162	fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
1163	fm_pos += sizeof(*fmh);
1164	ubi_assert(fm_pos <= ubi->fm_size);
1165
1166	fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
1167	fmsb->version = UBI_FM_FMT_VERSION;
1168	fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
1169	/* the max sqnum will be filled in while *reading* the fastmap */
1170	fmsb->sqnum = 0;
1171
1172	fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
1173	free_peb_count = 0;
1174	used_peb_count = 0;
1175	scrub_peb_count = 0;
1176	erase_peb_count = 0;
1177	vol_count = 0;
1178
1179	fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1180	fm_pos += sizeof(*fmpl);
1181	fmpl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1182	fmpl->size = cpu_to_be16(ubi->fm_pool.size);
1183	fmpl->max_size = cpu_to_be16(ubi->fm_pool.max_size);
1184
1185	for (i = 0; i < ubi->fm_pool.size; i++) {
1186		fmpl->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
1187		set_seen(ubi, ubi->fm_pool.pebs[i], seen_pebs);
1188	}
1189
1190	fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1191	fm_pos += sizeof(*fmpl_wl);
1192	fmpl_wl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1193	fmpl_wl->size = cpu_to_be16(ubi->fm_wl_pool.size);
1194	fmpl_wl->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
1195
1196	for (i = 0; i < ubi->fm_wl_pool.size; i++) {
1197		fmpl_wl->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
1198		set_seen(ubi, ubi->fm_wl_pool.pebs[i], seen_pebs);
1199	}
1200
1201	ubi_for_each_free_peb(ubi, wl_e, tmp_rb) {
1202		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1203
1204		fec->pnum = cpu_to_be32(wl_e->pnum);
1205		set_seen(ubi, wl_e->pnum, seen_pebs);
1206		fec->ec = cpu_to_be32(wl_e->ec);
1207
1208		free_peb_count++;
1209		fm_pos += sizeof(*fec);
1210		ubi_assert(fm_pos <= ubi->fm_size);
1211	}
1212	fmh->free_peb_count = cpu_to_be32(free_peb_count);
1213
1214	ubi_for_each_used_peb(ubi, wl_e, tmp_rb) {
1215		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1216
1217		fec->pnum = cpu_to_be32(wl_e->pnum);
1218		set_seen(ubi, wl_e->pnum, seen_pebs);
1219		fec->ec = cpu_to_be32(wl_e->ec);
1220
1221		used_peb_count++;
1222		fm_pos += sizeof(*fec);
1223		ubi_assert(fm_pos <= ubi->fm_size);
1224	}
1225
1226	ubi_for_each_protected_peb(ubi, i, wl_e) {
1227		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1228
1229		fec->pnum = cpu_to_be32(wl_e->pnum);
1230		set_seen(ubi, wl_e->pnum, seen_pebs);
1231		fec->ec = cpu_to_be32(wl_e->ec);
1232
1233		used_peb_count++;
1234		fm_pos += sizeof(*fec);
1235		ubi_assert(fm_pos <= ubi->fm_size);
1236	}
1237	fmh->used_peb_count = cpu_to_be32(used_peb_count);
1238
1239	ubi_for_each_scrub_peb(ubi, wl_e, tmp_rb) {
1240		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1241
1242		fec->pnum = cpu_to_be32(wl_e->pnum);
1243		set_seen(ubi, wl_e->pnum, seen_pebs);
1244		fec->ec = cpu_to_be32(wl_e->ec);
1245
1246		scrub_peb_count++;
1247		fm_pos += sizeof(*fec);
1248		ubi_assert(fm_pos <= ubi->fm_size);
1249	}
1250	fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
1251
1252
1253	list_for_each_entry(ubi_wrk, &ubi->works, list) {
1254		if (ubi_is_erase_work(ubi_wrk)) {
1255			wl_e = ubi_wrk->e;
1256			ubi_assert(wl_e);
1257
1258			fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1259
1260			fec->pnum = cpu_to_be32(wl_e->pnum);
1261			set_seen(ubi, wl_e->pnum, seen_pebs);
1262			fec->ec = cpu_to_be32(wl_e->ec);
1263
1264			erase_peb_count++;
1265			fm_pos += sizeof(*fec);
1266			ubi_assert(fm_pos <= ubi->fm_size);
1267		}
1268	}
1269	fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
1270
1271	for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
1272		vol = ubi->volumes[i];
1273
1274		if (!vol)
1275			continue;
1276
1277		vol_count++;
1278
1279		fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
1280		fm_pos += sizeof(*fvh);
1281		ubi_assert(fm_pos <= ubi->fm_size);
1282
1283		fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
1284		fvh->vol_id = cpu_to_be32(vol->vol_id);
1285		fvh->vol_type = vol->vol_type;
1286		fvh->used_ebs = cpu_to_be32(vol->used_ebs);
1287		fvh->data_pad = cpu_to_be32(vol->data_pad);
1288		fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
1289
1290		ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
1291			vol->vol_type == UBI_STATIC_VOLUME);
1292
1293		feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
1294		fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
1295		ubi_assert(fm_pos <= ubi->fm_size);
1296
1297		for (j = 0; j < vol->reserved_pebs; j++) {
1298			struct ubi_eba_leb_desc ldesc;
1299
1300			ubi_eba_get_ldesc(vol, j, &ldesc);
1301			feba->pnum[j] = cpu_to_be32(ldesc.pnum);
1302		}
1303
1304		feba->reserved_pebs = cpu_to_be32(j);
1305		feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
1306	}
1307	fmh->vol_count = cpu_to_be32(vol_count);
1308	fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
1309
1310	avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1311	avhdr->lnum = 0;
1312
1313	spin_unlock(&ubi->wl_lock);
1314	spin_unlock(&ubi->volumes_lock);
1315
1316	dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
1317	ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avbuf);
1318	if (ret) {
1319		ubi_err(ubi, "unable to write vid_hdr to fastmap SB!");
1320		goto out_kfree;
1321	}
1322
1323	for (i = 0; i < new_fm->used_blocks; i++) {
1324		fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
1325		set_seen(ubi, new_fm->e[i]->pnum, seen_pebs);
1326		fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
1327	}
1328
1329	fmsb->data_crc = 0;
1330	fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
1331					   ubi->fm_size));
1332
1333	for (i = 1; i < new_fm->used_blocks; i++) {
1334		dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1335		dvhdr->lnum = cpu_to_be32(i);
1336		dbg_bld("writing fastmap data to PEB %i sqnum %llu",
1337			new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
1338		ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvbuf);
1339		if (ret) {
1340			ubi_err(ubi, "unable to write vid_hdr to PEB %i!",
1341				new_fm->e[i]->pnum);
1342			goto out_kfree;
1343		}
1344	}
1345
1346	for (i = 0; i < new_fm->used_blocks; i++) {
1347		ret = ubi_io_write_data(ubi, fm_raw + (i * ubi->leb_size),
1348					new_fm->e[i]->pnum, 0, ubi->leb_size);
1349		if (ret) {
1350			ubi_err(ubi, "unable to write fastmap to PEB %i!",
1351				new_fm->e[i]->pnum);
1352			goto out_kfree;
1353		}
1354	}
1355
1356	ubi_assert(new_fm);
1357	ubi->fm = new_fm;
1358
1359	ret = self_check_seen(ubi, seen_pebs);
1360	dbg_bld("fastmap written!");
1361
1362out_kfree:
 
 
 
 
1363	ubi_free_vid_buf(avbuf);
1364	ubi_free_vid_buf(dvbuf);
1365	free_seen(seen_pebs);
1366out:
1367	return ret;
1368}
1369
1370/**
1371 * erase_block - Manually erase a PEB.
1372 * @ubi: UBI device object
1373 * @pnum: PEB to be erased
1374 *
1375 * Returns the new EC value on success, < 0 indicates an internal error.
1376 */
1377static int erase_block(struct ubi_device *ubi, int pnum)
1378{
1379	int ret;
1380	struct ubi_ec_hdr *ec_hdr;
1381	long long ec;
1382
1383	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1384	if (!ec_hdr)
1385		return -ENOMEM;
1386
1387	ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
1388	if (ret < 0)
1389		goto out;
1390	else if (ret && ret != UBI_IO_BITFLIPS) {
1391		ret = -EINVAL;
1392		goto out;
1393	}
1394
1395	ret = ubi_io_sync_erase(ubi, pnum, 0);
1396	if (ret < 0)
1397		goto out;
1398
1399	ec = be64_to_cpu(ec_hdr->ec);
1400	ec += ret;
1401	if (ec > UBI_MAX_ERASECOUNTER) {
1402		ret = -EINVAL;
1403		goto out;
1404	}
1405
1406	ec_hdr->ec = cpu_to_be64(ec);
1407	ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
1408	if (ret < 0)
1409		goto out;
1410
1411	ret = ec;
1412out:
1413	kfree(ec_hdr);
1414	return ret;
1415}
1416
1417/**
1418 * invalidate_fastmap - destroys a fastmap.
1419 * @ubi: UBI device object
1420 *
1421 * This function ensures that upon next UBI attach a full scan
1422 * is issued. We need this if UBI is about to write a new fastmap
1423 * but is unable to do so. In this case we have two options:
1424 * a) Make sure that the current fastmap will not be usued upon
1425 * attach time and contine or b) fall back to RO mode to have the
1426 * current fastmap in a valid state.
1427 * Returns 0 on success, < 0 indicates an internal error.
1428 */
1429static int invalidate_fastmap(struct ubi_device *ubi)
1430{
1431	int ret;
1432	struct ubi_fastmap_layout *fm;
1433	struct ubi_wl_entry *e;
1434	struct ubi_vid_io_buf *vb = NULL;
1435	struct ubi_vid_hdr *vh;
1436
1437	if (!ubi->fm)
1438		return 0;
1439
1440	ubi->fm = NULL;
1441
1442	ret = -ENOMEM;
1443	fm = kzalloc(sizeof(*fm), GFP_KERNEL);
1444	if (!fm)
1445		goto out;
1446
1447	vb = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
1448	if (!vb)
1449		goto out_free_fm;
1450
1451	vh = ubi_get_vid_hdr(vb);
1452
1453	ret = -ENOSPC;
1454	e = ubi_wl_get_fm_peb(ubi, 1);
1455	if (!e)
1456		goto out_free_fm;
1457
1458	/*
1459	 * Create fake fastmap such that UBI will fall back
1460	 * to scanning mode.
1461	 */
1462	vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1463	ret = ubi_io_write_vid_hdr(ubi, e->pnum, vb);
1464	if (ret < 0) {
1465		ubi_wl_put_fm_peb(ubi, e, 0, 0);
1466		goto out_free_fm;
1467	}
1468
1469	fm->used_blocks = 1;
1470	fm->e[0] = e;
1471
1472	ubi->fm = fm;
1473
1474out:
1475	ubi_free_vid_buf(vb);
1476	return ret;
1477
1478out_free_fm:
1479	kfree(fm);
1480	goto out;
1481}
1482
1483/**
1484 * return_fm_pebs - returns all PEBs used by a fastmap back to the
1485 * WL sub-system.
1486 * @ubi: UBI device object
1487 * @fm: fastmap layout object
1488 */
1489static void return_fm_pebs(struct ubi_device *ubi,
1490			   struct ubi_fastmap_layout *fm)
1491{
1492	int i;
1493
1494	if (!fm)
1495		return;
1496
1497	for (i = 0; i < fm->used_blocks; i++) {
1498		if (fm->e[i]) {
1499			ubi_wl_put_fm_peb(ubi, fm->e[i], i,
1500					  fm->to_be_tortured[i]);
1501			fm->e[i] = NULL;
1502		}
1503	}
1504}
1505
1506/**
1507 * ubi_update_fastmap - will be called by UBI if a volume changes or
1508 * a fastmap pool becomes full.
1509 * @ubi: UBI device object
1510 *
1511 * Returns 0 on success, < 0 indicates an internal error.
1512 */
1513int ubi_update_fastmap(struct ubi_device *ubi)
1514{
1515	int ret, i, j;
1516	struct ubi_fastmap_layout *new_fm, *old_fm;
1517	struct ubi_wl_entry *tmp_e;
1518
1519	down_write(&ubi->fm_protect);
1520	down_write(&ubi->work_sem);
1521	down_write(&ubi->fm_eba_sem);
1522
1523	ubi_refill_pools(ubi);
1524
1525	if (ubi->ro_mode || ubi->fm_disabled) {
1526		up_write(&ubi->fm_eba_sem);
1527		up_write(&ubi->work_sem);
1528		up_write(&ubi->fm_protect);
1529		return 0;
1530	}
1531
1532	ret = ubi_ensure_anchor_pebs(ubi);
1533	if (ret) {
1534		up_write(&ubi->fm_eba_sem);
1535		up_write(&ubi->work_sem);
1536		up_write(&ubi->fm_protect);
1537		return ret;
1538	}
1539
1540	new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
1541	if (!new_fm) {
1542		up_write(&ubi->fm_eba_sem);
1543		up_write(&ubi->work_sem);
1544		up_write(&ubi->fm_protect);
1545		return -ENOMEM;
1546	}
1547
1548	new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1549	old_fm = ubi->fm;
1550	ubi->fm = NULL;
1551
1552	if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1553		ubi_err(ubi, "fastmap too large");
1554		ret = -ENOSPC;
1555		goto err;
1556	}
1557
1558	for (i = 1; i < new_fm->used_blocks; i++) {
1559		spin_lock(&ubi->wl_lock);
1560		tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1561		spin_unlock(&ubi->wl_lock);
1562
1563		if (!tmp_e) {
1564			if (old_fm && old_fm->e[i]) {
1565				ret = erase_block(ubi, old_fm->e[i]->pnum);
1566				if (ret < 0) {
1567					ubi_err(ubi, "could not erase old fastmap PEB");
1568
1569					for (j = 1; j < i; j++) {
1570						ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1571								  j, 0);
1572						new_fm->e[j] = NULL;
1573					}
1574					goto err;
1575				}
1576				new_fm->e[i] = old_fm->e[i];
1577				old_fm->e[i] = NULL;
1578			} else {
1579				ubi_err(ubi, "could not get any free erase block");
1580
1581				for (j = 1; j < i; j++) {
1582					ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1583					new_fm->e[j] = NULL;
1584				}
1585
1586				ret = -ENOSPC;
1587				goto err;
1588			}
1589		} else {
1590			new_fm->e[i] = tmp_e;
1591
1592			if (old_fm && old_fm->e[i]) {
1593				ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1594						  old_fm->to_be_tortured[i]);
1595				old_fm->e[i] = NULL;
1596			}
1597		}
1598	}
1599
1600	/* Old fastmap is larger than the new one */
1601	if (old_fm && new_fm->used_blocks < old_fm->used_blocks) {
1602		for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) {
1603			ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1604					  old_fm->to_be_tortured[i]);
1605			old_fm->e[i] = NULL;
1606		}
1607	}
1608
1609	spin_lock(&ubi->wl_lock);
1610	tmp_e = ubi_wl_get_fm_peb(ubi, 1);
 
1611	spin_unlock(&ubi->wl_lock);
1612
1613	if (old_fm) {
1614		/* no fresh anchor PEB was found, reuse the old one */
1615		if (!tmp_e) {
1616			ret = erase_block(ubi, old_fm->e[0]->pnum);
1617			if (ret < 0) {
1618				ubi_err(ubi, "could not erase old anchor PEB");
1619
1620				for (i = 1; i < new_fm->used_blocks; i++) {
1621					ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1622							  i, 0);
1623					new_fm->e[i] = NULL;
1624				}
1625				goto err;
1626			}
1627			new_fm->e[0] = old_fm->e[0];
1628			new_fm->e[0]->ec = ret;
1629			old_fm->e[0] = NULL;
1630		} else {
1631			/* we've got a new anchor PEB, return the old one */
1632			ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1633					  old_fm->to_be_tortured[0]);
1634			new_fm->e[0] = tmp_e;
1635			old_fm->e[0] = NULL;
1636		}
1637	} else {
1638		if (!tmp_e) {
1639			ubi_err(ubi, "could not find any anchor PEB");
1640
1641			for (i = 1; i < new_fm->used_blocks; i++) {
1642				ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1643				new_fm->e[i] = NULL;
1644			}
1645
1646			ret = -ENOSPC;
1647			goto err;
1648		}
1649		new_fm->e[0] = tmp_e;
1650	}
1651
1652	ret = ubi_write_fastmap(ubi, new_fm);
1653
1654	if (ret)
1655		goto err;
1656
1657out_unlock:
1658	up_write(&ubi->fm_eba_sem);
1659	up_write(&ubi->work_sem);
1660	up_write(&ubi->fm_protect);
1661	kfree(old_fm);
 
 
 
1662	return ret;
1663
1664err:
1665	ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret);
1666
1667	ret = invalidate_fastmap(ubi);
1668	if (ret < 0) {
1669		ubi_err(ubi, "Unable to invalidate current fastmap!");
1670		ubi_ro_mode(ubi);
1671	} else {
1672		return_fm_pebs(ubi, old_fm);
1673		return_fm_pebs(ubi, new_fm);
1674		ret = 0;
1675	}
1676
1677	kfree(new_fm);
1678	goto out_unlock;
1679}