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v6.2
   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_KERNEL);
  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_vhdr - 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_KERNEL);
 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 * erase_block - Manually erase a PEB.
1394 * @ubi: UBI device object
1395 * @pnum: PEB to be erased
1396 *
1397 * Returns the new EC value on success, < 0 indicates an internal error.
1398 */
1399static int erase_block(struct ubi_device *ubi, int pnum)
1400{
1401	int ret;
1402	struct ubi_ec_hdr *ec_hdr;
1403	long long ec;
1404
1405	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1406	if (!ec_hdr)
1407		return -ENOMEM;
1408
1409	ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
1410	if (ret < 0)
1411		goto out;
1412	else if (ret && ret != UBI_IO_BITFLIPS) {
1413		ret = -EINVAL;
1414		goto out;
1415	}
1416
1417	ret = ubi_io_sync_erase(ubi, pnum, 0);
1418	if (ret < 0)
1419		goto out;
1420
1421	ec = be64_to_cpu(ec_hdr->ec);
1422	ec += ret;
1423	if (ec > UBI_MAX_ERASECOUNTER) {
1424		ret = -EINVAL;
1425		goto out;
1426	}
1427
1428	ec_hdr->ec = cpu_to_be64(ec);
1429	ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
1430	if (ret < 0)
1431		goto out;
1432
1433	ret = ec;
1434out:
1435	kfree(ec_hdr);
1436	return ret;
1437}
1438
1439/**
1440 * invalidate_fastmap - destroys a fastmap.
1441 * @ubi: UBI device object
1442 *
1443 * This function ensures that upon next UBI attach a full scan
1444 * is issued. We need this if UBI is about to write a new fastmap
1445 * but is unable to do so. In this case we have two options:
1446 * a) Make sure that the current fastmap will not be usued upon
1447 * attach time and contine or b) fall back to RO mode to have the
1448 * current fastmap in a valid state.
1449 * Returns 0 on success, < 0 indicates an internal error.
1450 */
1451static int invalidate_fastmap(struct ubi_device *ubi)
1452{
1453	int ret;
1454	struct ubi_fastmap_layout *fm;
1455	struct ubi_wl_entry *e;
1456	struct ubi_vid_io_buf *vb = NULL;
1457	struct ubi_vid_hdr *vh;
1458
1459	if (!ubi->fm)
1460		return 0;
1461
1462	ubi->fm = NULL;
1463
1464	ret = -ENOMEM;
1465	fm = kzalloc(sizeof(*fm), GFP_KERNEL);
1466	if (!fm)
1467		goto out;
1468
1469	vb = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
1470	if (!vb)
1471		goto out_free_fm;
1472
1473	vh = ubi_get_vid_hdr(vb);
1474
1475	ret = -ENOSPC;
1476	e = ubi_wl_get_fm_peb(ubi, 1);
1477	if (!e)
1478		goto out_free_fm;
1479
1480	/*
1481	 * Create fake fastmap such that UBI will fall back
1482	 * to scanning mode.
1483	 */
1484	vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1485	ret = ubi_io_write_vid_hdr(ubi, e->pnum, vb);
1486	if (ret < 0) {
1487		ubi_wl_put_fm_peb(ubi, e, 0, 0);
1488		goto out_free_fm;
1489	}
1490
1491	fm->used_blocks = 1;
1492	fm->e[0] = e;
1493
1494	ubi->fm = fm;
1495
1496out:
1497	ubi_free_vid_buf(vb);
1498	return ret;
1499
1500out_free_fm:
1501	kfree(fm);
1502	goto out;
1503}
1504
1505/**
1506 * return_fm_pebs - returns all PEBs used by a fastmap back to the
1507 * WL sub-system.
1508 * @ubi: UBI device object
1509 * @fm: fastmap layout object
1510 */
1511static void return_fm_pebs(struct ubi_device *ubi,
1512			   struct ubi_fastmap_layout *fm)
1513{
1514	int i;
1515
1516	if (!fm)
1517		return;
1518
1519	for (i = 0; i < fm->used_blocks; i++) {
1520		if (fm->e[i]) {
1521			ubi_wl_put_fm_peb(ubi, fm->e[i], i,
1522					  fm->to_be_tortured[i]);
1523			fm->e[i] = NULL;
1524		}
1525	}
1526}
1527
1528/**
1529 * ubi_update_fastmap - will be called by UBI if a volume changes or
1530 * a fastmap pool becomes full.
1531 * @ubi: UBI device object
1532 *
1533 * Returns 0 on success, < 0 indicates an internal error.
1534 */
1535int ubi_update_fastmap(struct ubi_device *ubi)
1536{
1537	int ret, i, j;
1538	struct ubi_fastmap_layout *new_fm, *old_fm;
1539	struct ubi_wl_entry *tmp_e;
1540
1541	down_write(&ubi->fm_protect);
1542	down_write(&ubi->work_sem);
1543	down_write(&ubi->fm_eba_sem);
1544
1545	ubi_refill_pools(ubi);
1546
1547	if (ubi->ro_mode || ubi->fm_disabled) {
1548		up_write(&ubi->fm_eba_sem);
1549		up_write(&ubi->work_sem);
1550		up_write(&ubi->fm_protect);
1551		return 0;
1552	}
1553
 
 
 
 
 
 
1554	new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
1555	if (!new_fm) {
1556		up_write(&ubi->fm_eba_sem);
1557		up_write(&ubi->work_sem);
1558		up_write(&ubi->fm_protect);
1559		return -ENOMEM;
1560	}
1561
1562	new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1563	old_fm = ubi->fm;
1564	ubi->fm = NULL;
1565
1566	if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1567		ubi_err(ubi, "fastmap too large");
1568		ret = -ENOSPC;
1569		goto err;
1570	}
1571
1572	for (i = 1; i < new_fm->used_blocks; i++) {
1573		spin_lock(&ubi->wl_lock);
1574		tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1575		spin_unlock(&ubi->wl_lock);
1576
1577		if (!tmp_e) {
1578			if (old_fm && old_fm->e[i]) {
1579				ret = erase_block(ubi, old_fm->e[i]->pnum);
1580				if (ret < 0) {
1581					ubi_err(ubi, "could not erase old fastmap PEB");
1582
1583					for (j = 1; j < i; j++) {
1584						ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1585								  j, 0);
1586						new_fm->e[j] = NULL;
1587					}
1588					goto err;
1589				}
1590				new_fm->e[i] = old_fm->e[i];
1591				old_fm->e[i] = NULL;
1592			} else {
1593				ubi_err(ubi, "could not get any free erase block");
1594
1595				for (j = 1; j < i; j++) {
1596					ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1597					new_fm->e[j] = NULL;
1598				}
1599
1600				ret = -ENOSPC;
1601				goto err;
1602			}
1603		} else {
1604			new_fm->e[i] = tmp_e;
1605
1606			if (old_fm && old_fm->e[i]) {
1607				ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1608						  old_fm->to_be_tortured[i]);
1609				old_fm->e[i] = NULL;
1610			}
1611		}
1612	}
1613
1614	/* Old fastmap is larger than the new one */
1615	if (old_fm && new_fm->used_blocks < old_fm->used_blocks) {
1616		for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) {
1617			ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1618					  old_fm->to_be_tortured[i]);
1619			old_fm->e[i] = NULL;
1620		}
1621	}
1622
1623	spin_lock(&ubi->wl_lock);
1624	tmp_e = ubi->fm_anchor;
1625	ubi->fm_anchor = NULL;
1626	spin_unlock(&ubi->wl_lock);
1627
1628	if (old_fm) {
1629		/* no fresh anchor PEB was found, reuse the old one */
1630		if (!tmp_e) {
1631			ret = erase_block(ubi, old_fm->e[0]->pnum);
1632			if (ret < 0) {
1633				ubi_err(ubi, "could not erase old anchor PEB");
1634
1635				for (i = 1; i < new_fm->used_blocks; i++) {
1636					ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1637							  i, 0);
1638					new_fm->e[i] = NULL;
1639				}
1640				goto err;
1641			}
1642			new_fm->e[0] = old_fm->e[0];
1643			new_fm->e[0]->ec = ret;
1644			old_fm->e[0] = NULL;
1645		} else {
1646			/* we've got a new anchor PEB, return the old one */
1647			ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1648					  old_fm->to_be_tortured[0]);
1649			new_fm->e[0] = tmp_e;
1650			old_fm->e[0] = NULL;
1651		}
1652	} else {
1653		if (!tmp_e) {
1654			ubi_err(ubi, "could not find any anchor PEB");
1655
1656			for (i = 1; i < new_fm->used_blocks; i++) {
1657				ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1658				new_fm->e[i] = NULL;
1659			}
1660
1661			ret = -ENOSPC;
1662			goto err;
1663		}
1664		new_fm->e[0] = tmp_e;
1665	}
1666
 
 
1667	ret = ubi_write_fastmap(ubi, new_fm);
 
 
1668
1669	if (ret)
1670		goto err;
1671
1672out_unlock:
1673	up_write(&ubi->fm_eba_sem);
1674	up_write(&ubi->work_sem);
1675	up_write(&ubi->fm_protect);
1676	kfree(old_fm);
1677
1678	ubi_ensure_anchor_pebs(ubi);
1679
1680	return ret;
1681
1682err:
1683	ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret);
1684
1685	ret = invalidate_fastmap(ubi);
1686	if (ret < 0) {
1687		ubi_err(ubi, "Unable to invalidate current fastmap!");
1688		ubi_ro_mode(ubi);
1689	} else {
1690		return_fm_pebs(ubi, old_fm);
1691		return_fm_pebs(ubi, new_fm);
1692		ret = 0;
1693	}
1694
1695	kfree(new_fm);
1696	goto out_unlock;
1697}
v4.6
 
   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 "ubi.h"
  19
  20/**
  21 * init_seen - allocate memory for used for debugging.
  22 * @ubi: UBI device description object
  23 */
  24static inline int *init_seen(struct ubi_device *ubi)
  25{
  26	int *ret;
  27
  28	if (!ubi_dbg_chk_fastmap(ubi))
  29		return NULL;
  30
  31	ret = kcalloc(ubi->peb_count, sizeof(int), GFP_KERNEL);
  32	if (!ret)
  33		return ERR_PTR(-ENOMEM);
  34
  35	return ret;
  36}
  37
  38/**
  39 * free_seen - free the seen logic integer array.
  40 * @seen: integer array of @ubi->peb_count size
  41 */
  42static inline void free_seen(int *seen)
  43{
  44	kfree(seen);
  45}
  46
  47/**
  48 * set_seen - mark a PEB as seen.
  49 * @ubi: UBI device description object
  50 * @pnum: The PEB to be makred as seen
  51 * @seen: integer array of @ubi->peb_count size
  52 */
  53static inline void set_seen(struct ubi_device *ubi, int pnum, int *seen)
  54{
  55	if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  56		return;
  57
  58	seen[pnum] = 1;
  59}
  60
  61/**
  62 * self_check_seen - check whether all PEB have been seen by fastmap.
  63 * @ubi: UBI device description object
  64 * @seen: integer array of @ubi->peb_count size
  65 */
  66static int self_check_seen(struct ubi_device *ubi, int *seen)
  67{
  68	int pnum, ret = 0;
  69
  70	if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  71		return 0;
  72
  73	for (pnum = 0; pnum < ubi->peb_count; pnum++) {
  74		if (!seen[pnum] && ubi->lookuptbl[pnum]) {
  75			ubi_err(ubi, "self-check failed for PEB %d, fastmap didn't see it", pnum);
  76			ret = -EINVAL;
  77		}
  78	}
  79
  80	return ret;
  81}
  82
  83/**
  84 * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
  85 * @ubi: UBI device description object
  86 */
  87size_t ubi_calc_fm_size(struct ubi_device *ubi)
  88{
  89	size_t size;
  90
  91	size = sizeof(struct ubi_fm_sb) +
  92		sizeof(struct ubi_fm_hdr) +
  93		sizeof(struct ubi_fm_scan_pool) +
  94		sizeof(struct ubi_fm_scan_pool) +
  95		(ubi->peb_count * sizeof(struct ubi_fm_ec)) +
  96		(sizeof(struct ubi_fm_eba) +
  97		(ubi->peb_count * sizeof(__be32))) +
  98		sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
  99	return roundup(size, ubi->leb_size);
 100}
 101
 102
 103/**
 104 * new_fm_vhdr - allocate a new volume header for fastmap usage.
 105 * @ubi: UBI device description object
 106 * @vol_id: the VID of the new header
 107 *
 108 * Returns a new struct ubi_vid_hdr on success.
 109 * NULL indicates out of memory.
 110 */
 111static struct ubi_vid_hdr *new_fm_vhdr(struct ubi_device *ubi, int vol_id)
 112{
 113	struct ubi_vid_hdr *new;
 
 114
 115	new = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 116	if (!new)
 117		goto out;
 118
 119	new->vol_type = UBI_VID_DYNAMIC;
 120	new->vol_id = cpu_to_be32(vol_id);
 
 121
 122	/* UBI implementations without fastmap support have to delete the
 123	 * fastmap.
 124	 */
 125	new->compat = UBI_COMPAT_DELETE;
 126
 127out:
 128	return new;
 129}
 130
 131/**
 132 * add_aeb - create and add a attach erase block to a given list.
 133 * @ai: UBI attach info object
 134 * @list: the target list
 135 * @pnum: PEB number of the new attach erase block
 136 * @ec: erease counter of the new LEB
 137 * @scrub: scrub this PEB after attaching
 138 *
 139 * Returns 0 on success, < 0 indicates an internal error.
 140 */
 141static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
 142		   int pnum, int ec, int scrub)
 143{
 144	struct ubi_ainf_peb *aeb;
 145
 146	aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL);
 147	if (!aeb)
 148		return -ENOMEM;
 149
 150	aeb->pnum = pnum;
 151	aeb->ec = ec;
 152	aeb->lnum = -1;
 153	aeb->scrub = scrub;
 154	aeb->copy_flag = aeb->sqnum = 0;
 155
 156	ai->ec_sum += aeb->ec;
 157	ai->ec_count++;
 158
 159	if (ai->max_ec < aeb->ec)
 160		ai->max_ec = aeb->ec;
 161
 162	if (ai->min_ec > aeb->ec)
 163		ai->min_ec = aeb->ec;
 164
 165	list_add_tail(&aeb->u.list, list);
 166
 167	return 0;
 168}
 169
 170/**
 171 * add_vol - create and add a new volume to ubi_attach_info.
 172 * @ai: ubi_attach_info object
 173 * @vol_id: VID of the new volume
 174 * @used_ebs: number of used EBS
 175 * @data_pad: data padding value of the new volume
 176 * @vol_type: volume type
 177 * @last_eb_bytes: number of bytes in the last LEB
 178 *
 179 * Returns the new struct ubi_ainf_volume on success.
 180 * NULL indicates an error.
 181 */
 182static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
 183				       int used_ebs, int data_pad, u8 vol_type,
 184				       int last_eb_bytes)
 185{
 186	struct ubi_ainf_volume *av;
 187	struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 188
 189	while (*p) {
 190		parent = *p;
 191		av = rb_entry(parent, struct ubi_ainf_volume, rb);
 192
 193		if (vol_id > av->vol_id)
 194			p = &(*p)->rb_left;
 195		else if (vol_id < av->vol_id)
 196			p = &(*p)->rb_right;
 197		else
 198			return ERR_PTR(-EINVAL);
 199	}
 200
 201	av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
 202	if (!av)
 203		goto out;
 204
 205	av->highest_lnum = av->leb_count = av->used_ebs = 0;
 206	av->vol_id = vol_id;
 207	av->data_pad = data_pad;
 208	av->last_data_size = last_eb_bytes;
 209	av->compat = 0;
 210	av->vol_type = vol_type;
 211	av->root = RB_ROOT;
 212	if (av->vol_type == UBI_STATIC_VOLUME)
 213		av->used_ebs = used_ebs;
 214
 215	dbg_bld("found volume (ID %i)", vol_id);
 216
 217	rb_link_node(&av->rb, parent, p);
 218	rb_insert_color(&av->rb, &ai->volumes);
 219
 220out:
 221	return av;
 222}
 223
 224/**
 225 * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
 226 * from it's original list.
 227 * @ai: ubi_attach_info object
 228 * @aeb: the to be assigned SEB
 229 * @av: target scan volume
 230 */
 231static void assign_aeb_to_av(struct ubi_attach_info *ai,
 232			     struct ubi_ainf_peb *aeb,
 233			     struct ubi_ainf_volume *av)
 234{
 235	struct ubi_ainf_peb *tmp_aeb;
 236	struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 237
 238	p = &av->root.rb_node;
 239	while (*p) {
 240		parent = *p;
 241
 242		tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 243		if (aeb->lnum != tmp_aeb->lnum) {
 244			if (aeb->lnum < tmp_aeb->lnum)
 245				p = &(*p)->rb_left;
 246			else
 247				p = &(*p)->rb_right;
 248
 249			continue;
 250		} else
 251			break;
 252	}
 253
 254	list_del(&aeb->u.list);
 255	av->leb_count++;
 256
 257	rb_link_node(&aeb->u.rb, parent, p);
 258	rb_insert_color(&aeb->u.rb, &av->root);
 259}
 260
 261/**
 262 * update_vol - inserts or updates a LEB which was found a pool.
 263 * @ubi: the UBI device object
 264 * @ai: attach info object
 265 * @av: the volume this LEB belongs to
 266 * @new_vh: the volume header derived from new_aeb
 267 * @new_aeb: the AEB to be examined
 268 *
 269 * Returns 0 on success, < 0 indicates an internal error.
 270 */
 271static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
 272		      struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
 273		      struct ubi_ainf_peb *new_aeb)
 274{
 275	struct rb_node **p = &av->root.rb_node, *parent = NULL;
 276	struct ubi_ainf_peb *aeb, *victim;
 277	int cmp_res;
 278
 279	while (*p) {
 280		parent = *p;
 281		aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 282
 283		if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
 284			if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
 285				p = &(*p)->rb_left;
 286			else
 287				p = &(*p)->rb_right;
 288
 289			continue;
 290		}
 291
 292		/* This case can happen if the fastmap gets written
 293		 * because of a volume change (creation, deletion, ..).
 294		 * Then a PEB can be within the persistent EBA and the pool.
 295		 */
 296		if (aeb->pnum == new_aeb->pnum) {
 297			ubi_assert(aeb->lnum == new_aeb->lnum);
 298			kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 299
 300			return 0;
 301		}
 302
 303		cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
 304		if (cmp_res < 0)
 305			return cmp_res;
 306
 307		/* new_aeb is newer */
 308		if (cmp_res & 1) {
 309			victim = kmem_cache_alloc(ai->aeb_slab_cache,
 310				GFP_KERNEL);
 311			if (!victim)
 312				return -ENOMEM;
 313
 314			victim->ec = aeb->ec;
 315			victim->pnum = aeb->pnum;
 316			list_add_tail(&victim->u.list, &ai->erase);
 317
 318			if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
 319				av->last_data_size =
 320					be32_to_cpu(new_vh->data_size);
 321
 322			dbg_bld("vol %i: AEB %i's PEB %i is the newer",
 323				av->vol_id, aeb->lnum, new_aeb->pnum);
 324
 325			aeb->ec = new_aeb->ec;
 326			aeb->pnum = new_aeb->pnum;
 327			aeb->copy_flag = new_vh->copy_flag;
 328			aeb->scrub = new_aeb->scrub;
 329			kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 
 330
 331		/* new_aeb is older */
 332		} else {
 333			dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
 334				av->vol_id, aeb->lnum, new_aeb->pnum);
 335			list_add_tail(&new_aeb->u.list, &ai->erase);
 336		}
 337
 338		return 0;
 339	}
 340	/* This LEB is new, let's add it to the volume */
 341
 342	if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
 343		av->highest_lnum = be32_to_cpu(new_vh->lnum);
 344		av->last_data_size = be32_to_cpu(new_vh->data_size);
 345	}
 346
 347	if (av->vol_type == UBI_STATIC_VOLUME)
 348		av->used_ebs = be32_to_cpu(new_vh->used_ebs);
 349
 350	av->leb_count++;
 351
 352	rb_link_node(&new_aeb->u.rb, parent, p);
 353	rb_insert_color(&new_aeb->u.rb, &av->root);
 354
 355	return 0;
 356}
 357
 358/**
 359 * process_pool_aeb - we found a non-empty PEB in a pool.
 360 * @ubi: UBI device object
 361 * @ai: attach info object
 362 * @new_vh: the volume header derived from new_aeb
 363 * @new_aeb: the AEB to be examined
 364 *
 365 * Returns 0 on success, < 0 indicates an internal error.
 366 */
 367static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 368			    struct ubi_vid_hdr *new_vh,
 369			    struct ubi_ainf_peb *new_aeb)
 370{
 371	struct ubi_ainf_volume *av, *tmp_av = NULL;
 372	struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 373	int found = 0;
 374
 375	if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID ||
 376		be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {
 377		kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 378
 379		return 0;
 380	}
 381
 382	/* Find the volume this SEB belongs to */
 383	while (*p) {
 384		parent = *p;
 385		tmp_av = rb_entry(parent, struct ubi_ainf_volume, rb);
 386
 387		if (be32_to_cpu(new_vh->vol_id) > tmp_av->vol_id)
 388			p = &(*p)->rb_left;
 389		else if (be32_to_cpu(new_vh->vol_id) < tmp_av->vol_id)
 390			p = &(*p)->rb_right;
 391		else {
 392			found = 1;
 393			break;
 394		}
 395	}
 396
 397	if (found)
 398		av = tmp_av;
 399	else {
 400		ubi_err(ubi, "orphaned volume in fastmap pool!");
 401		kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 402		return UBI_BAD_FASTMAP;
 403	}
 404
 405	ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);
 406
 407	return update_vol(ubi, ai, av, new_vh, new_aeb);
 408}
 409
 410/**
 411 * unmap_peb - unmap a PEB.
 412 * If fastmap detects a free PEB in the pool it has to check whether
 413 * this PEB has been unmapped after writing the fastmap.
 414 *
 415 * @ai: UBI attach info object
 416 * @pnum: The PEB to be unmapped
 417 */
 418static void unmap_peb(struct ubi_attach_info *ai, int pnum)
 419{
 420	struct ubi_ainf_volume *av;
 421	struct rb_node *node, *node2;
 422	struct ubi_ainf_peb *aeb;
 423
 424	for (node = rb_first(&ai->volumes); node; node = rb_next(node)) {
 425		av = rb_entry(node, struct ubi_ainf_volume, rb);
 426
 427		for (node2 = rb_first(&av->root); node2;
 428		     node2 = rb_next(node2)) {
 429			aeb = rb_entry(node2, struct ubi_ainf_peb, u.rb);
 430			if (aeb->pnum == pnum) {
 431				rb_erase(&aeb->u.rb, &av->root);
 432				av->leb_count--;
 433				kmem_cache_free(ai->aeb_slab_cache, aeb);
 434				return;
 435			}
 436		}
 437	}
 438}
 439
 440/**
 441 * scan_pool - scans a pool for changed (no longer empty PEBs).
 442 * @ubi: UBI device object
 443 * @ai: attach info object
 444 * @pebs: an array of all PEB numbers in the to be scanned pool
 445 * @pool_size: size of the pool (number of entries in @pebs)
 446 * @max_sqnum: pointer to the maximal sequence number
 447 * @free: list of PEBs which are most likely free (and go into @ai->free)
 448 *
 449 * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
 450 * < 0 indicates an internal error.
 451 */
 452static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 453		     __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 454		     struct list_head *free)
 455{
 
 456	struct ubi_vid_hdr *vh;
 457	struct ubi_ec_hdr *ech;
 458	struct ubi_ainf_peb *new_aeb;
 459	int i, pnum, err, ret = 0;
 460
 461	ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 462	if (!ech)
 463		return -ENOMEM;
 464
 465	vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 466	if (!vh) {
 467		kfree(ech);
 468		return -ENOMEM;
 469	}
 470
 
 
 471	dbg_bld("scanning fastmap pool: size = %i", pool_size);
 472
 473	/*
 474	 * Now scan all PEBs in the pool to find changes which have been made
 475	 * after the creation of the fastmap
 476	 */
 477	for (i = 0; i < pool_size; i++) {
 478		int scrub = 0;
 479		int image_seq;
 480
 481		pnum = be32_to_cpu(pebs[i]);
 482
 483		if (ubi_io_is_bad(ubi, pnum)) {
 484			ubi_err(ubi, "bad PEB in fastmap pool!");
 485			ret = UBI_BAD_FASTMAP;
 486			goto out;
 487		}
 488
 489		err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 490		if (err && err != UBI_IO_BITFLIPS) {
 491			ubi_err(ubi, "unable to read EC header! PEB:%i err:%i",
 492				pnum, err);
 493			ret = err > 0 ? UBI_BAD_FASTMAP : err;
 494			goto out;
 495		} else if (err == UBI_IO_BITFLIPS)
 496			scrub = 1;
 497
 498		/*
 499		 * Older UBI implementations have image_seq set to zero, so
 500		 * we shouldn't fail if image_seq == 0.
 501		 */
 502		image_seq = be32_to_cpu(ech->image_seq);
 503
 504		if (image_seq && (image_seq != ubi->image_seq)) {
 505			ubi_err(ubi, "bad image seq: 0x%x, expected: 0x%x",
 506				be32_to_cpu(ech->image_seq), ubi->image_seq);
 507			ret = UBI_BAD_FASTMAP;
 508			goto out;
 509		}
 510
 511		err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
 512		if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
 513			unsigned long long ec = be64_to_cpu(ech->ec);
 514			unmap_peb(ai, pnum);
 515			dbg_bld("Adding PEB to free: %i", pnum);
 
 516			if (err == UBI_IO_FF_BITFLIPS)
 517				add_aeb(ai, free, pnum, ec, 1);
 518			else
 519				add_aeb(ai, free, pnum, ec, 0);
 
 
 520			continue;
 521		} else if (err == 0 || err == UBI_IO_BITFLIPS) {
 522			dbg_bld("Found non empty PEB:%i in pool", pnum);
 523
 524			if (err == UBI_IO_BITFLIPS)
 525				scrub = 1;
 526
 527			new_aeb = kmem_cache_alloc(ai->aeb_slab_cache,
 528						   GFP_KERNEL);
 529			if (!new_aeb) {
 530				ret = -ENOMEM;
 531				goto out;
 532			}
 533
 534			new_aeb->ec = be64_to_cpu(ech->ec);
 535			new_aeb->pnum = pnum;
 536			new_aeb->lnum = be32_to_cpu(vh->lnum);
 537			new_aeb->sqnum = be64_to_cpu(vh->sqnum);
 538			new_aeb->copy_flag = vh->copy_flag;
 539			new_aeb->scrub = scrub;
 540
 541			if (*max_sqnum < new_aeb->sqnum)
 542				*max_sqnum = new_aeb->sqnum;
 543
 544			err = process_pool_aeb(ubi, ai, vh, new_aeb);
 545			if (err) {
 546				ret = err > 0 ? UBI_BAD_FASTMAP : err;
 547				goto out;
 548			}
 549		} else {
 550			/* We are paranoid and fall back to scanning mode */
 551			ubi_err(ubi, "fastmap pool PEBs contains damaged PEBs!");
 552			ret = err > 0 ? UBI_BAD_FASTMAP : err;
 553			goto out;
 554		}
 555
 556	}
 557
 558out:
 559	ubi_free_vid_hdr(ubi, vh);
 560	kfree(ech);
 561	return ret;
 562}
 563
 564/**
 565 * count_fastmap_pebs - Counts the PEBs found by fastmap.
 566 * @ai: The UBI attach info object
 567 */
 568static int count_fastmap_pebs(struct ubi_attach_info *ai)
 569{
 570	struct ubi_ainf_peb *aeb;
 571	struct ubi_ainf_volume *av;
 572	struct rb_node *rb1, *rb2;
 573	int n = 0;
 574
 575	list_for_each_entry(aeb, &ai->erase, u.list)
 576		n++;
 577
 578	list_for_each_entry(aeb, &ai->free, u.list)
 579		n++;
 580
 581	 ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
 582		ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
 583			n++;
 584
 585	return n;
 586}
 587
 588/**
 589 * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
 590 * @ubi: UBI device object
 591 * @ai: UBI attach info object
 592 * @fm: the fastmap to be attached
 593 *
 594 * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
 595 * < 0 indicates an internal error.
 596 */
 597static int ubi_attach_fastmap(struct ubi_device *ubi,
 598			      struct ubi_attach_info *ai,
 599			      struct ubi_fastmap_layout *fm)
 600{
 601	struct list_head used, free;
 602	struct ubi_ainf_volume *av;
 603	struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
 604	struct ubi_fm_sb *fmsb;
 605	struct ubi_fm_hdr *fmhdr;
 606	struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
 607	struct ubi_fm_ec *fmec;
 608	struct ubi_fm_volhdr *fmvhdr;
 609	struct ubi_fm_eba *fm_eba;
 610	int ret, i, j, pool_size, wl_pool_size;
 611	size_t fm_pos = 0, fm_size = ubi->fm_size;
 612	unsigned long long max_sqnum = 0;
 613	void *fm_raw = ubi->fm_buf;
 614
 615	INIT_LIST_HEAD(&used);
 616	INIT_LIST_HEAD(&free);
 617	ai->min_ec = UBI_MAX_ERASECOUNTER;
 618
 619	fmsb = (struct ubi_fm_sb *)(fm_raw);
 620	ai->max_sqnum = fmsb->sqnum;
 621	fm_pos += sizeof(struct ubi_fm_sb);
 622	if (fm_pos >= fm_size)
 623		goto fail_bad;
 624
 625	fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
 626	fm_pos += sizeof(*fmhdr);
 627	if (fm_pos >= fm_size)
 628		goto fail_bad;
 629
 630	if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
 631		ubi_err(ubi, "bad fastmap header magic: 0x%x, expected: 0x%x",
 632			be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
 633		goto fail_bad;
 634	}
 635
 636	fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 637	fm_pos += sizeof(*fmpl);
 638	if (fm_pos >= fm_size)
 639		goto fail_bad;
 640	if (be32_to_cpu(fmpl->magic) != UBI_FM_POOL_MAGIC) {
 641		ubi_err(ubi, "bad fastmap pool magic: 0x%x, expected: 0x%x",
 642			be32_to_cpu(fmpl->magic), UBI_FM_POOL_MAGIC);
 643		goto fail_bad;
 644	}
 645
 646	fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 647	fm_pos += sizeof(*fmpl_wl);
 648	if (fm_pos >= fm_size)
 649		goto fail_bad;
 650	if (be32_to_cpu(fmpl_wl->magic) != UBI_FM_POOL_MAGIC) {
 651		ubi_err(ubi, "bad fastmap WL pool magic: 0x%x, expected: 0x%x",
 652			be32_to_cpu(fmpl_wl->magic), UBI_FM_POOL_MAGIC);
 653		goto fail_bad;
 654	}
 655
 656	pool_size = be16_to_cpu(fmpl->size);
 657	wl_pool_size = be16_to_cpu(fmpl_wl->size);
 658	fm->max_pool_size = be16_to_cpu(fmpl->max_size);
 659	fm->max_wl_pool_size = be16_to_cpu(fmpl_wl->max_size);
 660
 661	if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
 662		ubi_err(ubi, "bad pool size: %i", pool_size);
 663		goto fail_bad;
 664	}
 665
 666	if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
 667		ubi_err(ubi, "bad WL pool size: %i", wl_pool_size);
 668		goto fail_bad;
 669	}
 670
 671
 672	if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
 673	    fm->max_pool_size < 0) {
 674		ubi_err(ubi, "bad maximal pool size: %i", fm->max_pool_size);
 675		goto fail_bad;
 676	}
 677
 678	if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
 679	    fm->max_wl_pool_size < 0) {
 680		ubi_err(ubi, "bad maximal WL pool size: %i",
 681			fm->max_wl_pool_size);
 682		goto fail_bad;
 683	}
 684
 685	/* read EC values from free list */
 686	for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
 687		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 688		fm_pos += sizeof(*fmec);
 689		if (fm_pos >= fm_size)
 690			goto fail_bad;
 691
 692		add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
 693			be32_to_cpu(fmec->ec), 0);
 
 
 694	}
 695
 696	/* read EC values from used list */
 697	for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
 698		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 699		fm_pos += sizeof(*fmec);
 700		if (fm_pos >= fm_size)
 701			goto fail_bad;
 702
 703		add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 704			be32_to_cpu(fmec->ec), 0);
 
 
 705	}
 706
 707	/* read EC values from scrub list */
 708	for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
 709		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 710		fm_pos += sizeof(*fmec);
 711		if (fm_pos >= fm_size)
 712			goto fail_bad;
 713
 714		add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 715			be32_to_cpu(fmec->ec), 1);
 
 
 716	}
 717
 718	/* read EC values from erase list */
 719	for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
 720		fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 721		fm_pos += sizeof(*fmec);
 722		if (fm_pos >= fm_size)
 723			goto fail_bad;
 724
 725		add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
 726			be32_to_cpu(fmec->ec), 1);
 
 
 727	}
 728
 729	ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
 730	ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
 731
 732	/* Iterate over all volumes and read their EBA table */
 733	for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
 734		fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
 735		fm_pos += sizeof(*fmvhdr);
 736		if (fm_pos >= fm_size)
 737			goto fail_bad;
 738
 739		if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
 740			ubi_err(ubi, "bad fastmap vol header magic: 0x%x, expected: 0x%x",
 741				be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
 742			goto fail_bad;
 743		}
 744
 745		av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
 746			     be32_to_cpu(fmvhdr->used_ebs),
 747			     be32_to_cpu(fmvhdr->data_pad),
 748			     fmvhdr->vol_type,
 749			     be32_to_cpu(fmvhdr->last_eb_bytes));
 750
 751		if (!av)
 752			goto fail_bad;
 753		if (PTR_ERR(av) == -EINVAL) {
 754			ubi_err(ubi, "volume (ID %i) already exists",
 755				fmvhdr->vol_id);
 756			goto fail_bad;
 757		}
 758
 759		ai->vols_found++;
 760		if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
 761			ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
 762
 763		fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
 764		fm_pos += sizeof(*fm_eba);
 765		fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
 766		if (fm_pos >= fm_size)
 767			goto fail_bad;
 768
 769		if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
 770			ubi_err(ubi, "bad fastmap EBA header magic: 0x%x, expected: 0x%x",
 771				be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
 772			goto fail_bad;
 773		}
 774
 775		for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
 776			int pnum = be32_to_cpu(fm_eba->pnum[j]);
 777
 778			if (pnum < 0)
 779				continue;
 780
 781			aeb = NULL;
 782			list_for_each_entry(tmp_aeb, &used, u.list) {
 783				if (tmp_aeb->pnum == pnum) {
 784					aeb = tmp_aeb;
 785					break;
 786				}
 787			}
 788
 789			if (!aeb) {
 790				ubi_err(ubi, "PEB %i is in EBA but not in used list", pnum);
 791				goto fail_bad;
 792			}
 793
 794			aeb->lnum = j;
 795
 796			if (av->highest_lnum <= aeb->lnum)
 797				av->highest_lnum = aeb->lnum;
 798
 799			assign_aeb_to_av(ai, aeb, av);
 800
 801			dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
 802				aeb->pnum, aeb->lnum, av->vol_id);
 803		}
 804	}
 805
 806	ret = scan_pool(ubi, ai, fmpl->pebs, pool_size, &max_sqnum, &free);
 807	if (ret)
 808		goto fail;
 809
 810	ret = scan_pool(ubi, ai, fmpl_wl->pebs, wl_pool_size, &max_sqnum, &free);
 811	if (ret)
 812		goto fail;
 813
 814	if (max_sqnum > ai->max_sqnum)
 815		ai->max_sqnum = max_sqnum;
 816
 817	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list)
 818		list_move_tail(&tmp_aeb->u.list, &ai->free);
 819
 820	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list)
 821		list_move_tail(&tmp_aeb->u.list, &ai->erase);
 822
 823	ubi_assert(list_empty(&free));
 824
 825	/*
 826	 * If fastmap is leaking PEBs (must not happen), raise a
 827	 * fat warning and fall back to scanning mode.
 828	 * We do this here because in ubi_wl_init() it's too late
 829	 * and we cannot fall back to scanning.
 830	 */
 831	if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
 832		    ai->bad_peb_count - fm->used_blocks))
 833		goto fail_bad;
 834
 835	return 0;
 836
 837fail_bad:
 838	ret = UBI_BAD_FASTMAP;
 839fail:
 840	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) {
 841		list_del(&tmp_aeb->u.list);
 842		kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
 843	}
 844	list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) {
 845		list_del(&tmp_aeb->u.list);
 846		kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
 847	}
 848
 849	return ret;
 850}
 851
 852/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 853 * ubi_scan_fastmap - scan the fastmap.
 854 * @ubi: UBI device object
 855 * @ai: UBI attach info to be filled
 856 * @fm_anchor: The fastmap starts at this PEB
 
 857 *
 858 * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
 859 * UBI_BAD_FASTMAP if one was found but is not usable.
 860 * < 0 indicates an internal error.
 861 */
 862int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 863		     int fm_anchor)
 864{
 865	struct ubi_fm_sb *fmsb, *fmsb2;
 
 866	struct ubi_vid_hdr *vh;
 867	struct ubi_ec_hdr *ech;
 868	struct ubi_fastmap_layout *fm;
 869	int i, used_blocks, pnum, ret = 0;
 
 870	size_t fm_size;
 871	__be32 crc, tmp_crc;
 872	unsigned long long sqnum = 0;
 873
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 874	down_write(&ubi->fm_protect);
 875	memset(ubi->fm_buf, 0, ubi->fm_size);
 876
 877	fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
 878	if (!fmsb) {
 879		ret = -ENOMEM;
 880		goto out;
 881	}
 882
 883	fm = kzalloc(sizeof(*fm), GFP_KERNEL);
 884	if (!fm) {
 885		ret = -ENOMEM;
 886		kfree(fmsb);
 887		goto out;
 888	}
 889
 890	ret = ubi_io_read(ubi, fmsb, fm_anchor, ubi->leb_start, sizeof(*fmsb));
 891	if (ret && ret != UBI_IO_BITFLIPS)
 892		goto free_fm_sb;
 893	else if (ret == UBI_IO_BITFLIPS)
 894		fm->to_be_tortured[0] = 1;
 895
 896	if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
 897		ubi_err(ubi, "bad super block magic: 0x%x, expected: 0x%x",
 898			be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
 899		ret = UBI_BAD_FASTMAP;
 900		goto free_fm_sb;
 901	}
 902
 903	if (fmsb->version != UBI_FM_FMT_VERSION) {
 904		ubi_err(ubi, "bad fastmap version: %i, expected: %i",
 905			fmsb->version, UBI_FM_FMT_VERSION);
 906		ret = UBI_BAD_FASTMAP;
 907		goto free_fm_sb;
 908	}
 909
 910	used_blocks = be32_to_cpu(fmsb->used_blocks);
 911	if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
 912		ubi_err(ubi, "number of fastmap blocks is invalid: %i",
 913			used_blocks);
 914		ret = UBI_BAD_FASTMAP;
 915		goto free_fm_sb;
 916	}
 917
 918	fm_size = ubi->leb_size * used_blocks;
 919	if (fm_size != ubi->fm_size) {
 920		ubi_err(ubi, "bad fastmap size: %zi, expected: %zi",
 921			fm_size, ubi->fm_size);
 922		ret = UBI_BAD_FASTMAP;
 923		goto free_fm_sb;
 924	}
 925
 926	ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 927	if (!ech) {
 928		ret = -ENOMEM;
 929		goto free_fm_sb;
 930	}
 931
 932	vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 933	if (!vh) {
 934		ret = -ENOMEM;
 935		goto free_hdr;
 936	}
 937
 
 
 938	for (i = 0; i < used_blocks; i++) {
 939		int image_seq;
 940
 941		pnum = be32_to_cpu(fmsb->block_loc[i]);
 942
 943		if (ubi_io_is_bad(ubi, pnum)) {
 944			ret = UBI_BAD_FASTMAP;
 945			goto free_hdr;
 946		}
 947
 
 
 
 
 
 
 
 948		ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 949		if (ret && ret != UBI_IO_BITFLIPS) {
 950			ubi_err(ubi, "unable to read fastmap block# %i EC (PEB: %i)",
 951				i, pnum);
 952			if (ret > 0)
 953				ret = UBI_BAD_FASTMAP;
 954			goto free_hdr;
 955		} else if (ret == UBI_IO_BITFLIPS)
 956			fm->to_be_tortured[i] = 1;
 957
 958		image_seq = be32_to_cpu(ech->image_seq);
 959		if (!ubi->image_seq)
 960			ubi->image_seq = image_seq;
 961
 962		/*
 963		 * Older UBI implementations have image_seq set to zero, so
 964		 * we shouldn't fail if image_seq == 0.
 965		 */
 966		if (image_seq && (image_seq != ubi->image_seq)) {
 967			ubi_err(ubi, "wrong image seq:%d instead of %d",
 968				be32_to_cpu(ech->image_seq), ubi->image_seq);
 969			ret = UBI_BAD_FASTMAP;
 970			goto free_hdr;
 971		}
 972
 973		ret = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
 974		if (ret && ret != UBI_IO_BITFLIPS) {
 975			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i)",
 976				i, pnum);
 977			goto free_hdr;
 978		}
 979
 980		if (i == 0) {
 981			if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
 982				ubi_err(ubi, "bad fastmap anchor vol_id: 0x%x, expected: 0x%x",
 983					be32_to_cpu(vh->vol_id),
 984					UBI_FM_SB_VOLUME_ID);
 985				ret = UBI_BAD_FASTMAP;
 986				goto free_hdr;
 987			}
 988		} else {
 989			if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
 990				ubi_err(ubi, "bad fastmap data vol_id: 0x%x, expected: 0x%x",
 991					be32_to_cpu(vh->vol_id),
 992					UBI_FM_DATA_VOLUME_ID);
 993				ret = UBI_BAD_FASTMAP;
 994				goto free_hdr;
 995			}
 996		}
 997
 998		if (sqnum < be64_to_cpu(vh->sqnum))
 999			sqnum = be64_to_cpu(vh->sqnum);
1000
1001		ret = ubi_io_read(ubi, ubi->fm_buf + (ubi->leb_size * i), pnum,
1002				  ubi->leb_start, ubi->leb_size);
1003		if (ret && ret != UBI_IO_BITFLIPS) {
1004			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i, "
1005				"err: %i)", i, pnum, ret);
1006			goto free_hdr;
1007		}
1008	}
1009
1010	kfree(fmsb);
1011	fmsb = NULL;
1012
1013	fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
1014	tmp_crc = be32_to_cpu(fmsb2->data_crc);
1015	fmsb2->data_crc = 0;
1016	crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
1017	if (crc != tmp_crc) {
1018		ubi_err(ubi, "fastmap data CRC is invalid");
1019		ubi_err(ubi, "CRC should be: 0x%x, calc: 0x%x",
1020			tmp_crc, crc);
1021		ret = UBI_BAD_FASTMAP;
1022		goto free_hdr;
1023	}
1024
1025	fmsb2->sqnum = sqnum;
1026
1027	fm->used_blocks = used_blocks;
1028
1029	ret = ubi_attach_fastmap(ubi, ai, fm);
1030	if (ret) {
1031		if (ret > 0)
1032			ret = UBI_BAD_FASTMAP;
1033		goto free_hdr;
1034	}
1035
1036	for (i = 0; i < used_blocks; i++) {
1037		struct ubi_wl_entry *e;
1038
1039		e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1040		if (!e) {
1041			while (i--)
1042				kfree(fm->e[i]);
1043
1044			ret = -ENOMEM;
1045			goto free_hdr;
1046		}
1047
1048		e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
1049		e->ec = be32_to_cpu(fmsb2->block_ec[i]);
1050		fm->e[i] = e;
1051	}
1052
1053	ubi->fm = fm;
1054	ubi->fm_pool.max_size = ubi->fm->max_pool_size;
1055	ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
1056	ubi_msg(ubi, "attached by fastmap");
1057	ubi_msg(ubi, "fastmap pool size: %d", ubi->fm_pool.max_size);
1058	ubi_msg(ubi, "fastmap WL pool size: %d",
1059		ubi->fm_wl_pool.max_size);
1060	ubi->fm_disabled = 0;
 
1061
1062	ubi_free_vid_hdr(ubi, vh);
1063	kfree(ech);
1064out:
1065	up_write(&ubi->fm_protect);
1066	if (ret == UBI_BAD_FASTMAP)
1067		ubi_err(ubi, "Attach by fastmap failed, doing a full scan!");
1068	return ret;
1069
1070free_hdr:
1071	ubi_free_vid_hdr(ubi, vh);
1072	kfree(ech);
1073free_fm_sb:
1074	kfree(fmsb);
1075	kfree(fm);
1076	goto out;
1077}
1078
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1079/**
1080 * ubi_write_fastmap - writes a fastmap.
1081 * @ubi: UBI device object
1082 * @new_fm: the to be written fastmap
1083 *
1084 * Returns 0 on success, < 0 indicates an internal error.
1085 */
1086static int ubi_write_fastmap(struct ubi_device *ubi,
1087			     struct ubi_fastmap_layout *new_fm)
1088{
1089	size_t fm_pos = 0;
1090	void *fm_raw;
1091	struct ubi_fm_sb *fmsb;
1092	struct ubi_fm_hdr *fmh;
1093	struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
1094	struct ubi_fm_ec *fec;
1095	struct ubi_fm_volhdr *fvh;
1096	struct ubi_fm_eba *feba;
1097	struct ubi_wl_entry *wl_e;
1098	struct ubi_volume *vol;
 
1099	struct ubi_vid_hdr *avhdr, *dvhdr;
1100	struct ubi_work *ubi_wrk;
1101	struct rb_node *tmp_rb;
1102	int ret, i, j, free_peb_count, used_peb_count, vol_count;
1103	int scrub_peb_count, erase_peb_count;
1104	int *seen_pebs = NULL;
1105
1106	fm_raw = ubi->fm_buf;
1107	memset(ubi->fm_buf, 0, ubi->fm_size);
1108
1109	avhdr = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1110	if (!avhdr) {
1111		ret = -ENOMEM;
1112		goto out;
1113	}
1114
1115	dvhdr = new_fm_vhdr(ubi, UBI_FM_DATA_VOLUME_ID);
1116	if (!dvhdr) {
1117		ret = -ENOMEM;
1118		goto out_kfree;
1119	}
1120
 
 
 
1121	seen_pebs = init_seen(ubi);
1122	if (IS_ERR(seen_pebs)) {
1123		ret = PTR_ERR(seen_pebs);
1124		goto out_kfree;
1125	}
1126
1127	spin_lock(&ubi->volumes_lock);
1128	spin_lock(&ubi->wl_lock);
1129
1130	fmsb = (struct ubi_fm_sb *)fm_raw;
1131	fm_pos += sizeof(*fmsb);
1132	ubi_assert(fm_pos <= ubi->fm_size);
1133
1134	fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
1135	fm_pos += sizeof(*fmh);
1136	ubi_assert(fm_pos <= ubi->fm_size);
1137
1138	fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
1139	fmsb->version = UBI_FM_FMT_VERSION;
1140	fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
1141	/* the max sqnum will be filled in while *reading* the fastmap */
1142	fmsb->sqnum = 0;
1143
1144	fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
1145	free_peb_count = 0;
1146	used_peb_count = 0;
1147	scrub_peb_count = 0;
1148	erase_peb_count = 0;
1149	vol_count = 0;
1150
1151	fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1152	fm_pos += sizeof(*fmpl);
1153	fmpl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1154	fmpl->size = cpu_to_be16(ubi->fm_pool.size);
1155	fmpl->max_size = cpu_to_be16(ubi->fm_pool.max_size);
1156
1157	for (i = 0; i < ubi->fm_pool.size; i++) {
1158		fmpl->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
1159		set_seen(ubi, ubi->fm_pool.pebs[i], seen_pebs);
1160	}
1161
1162	fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1163	fm_pos += sizeof(*fmpl_wl);
1164	fmpl_wl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1165	fmpl_wl->size = cpu_to_be16(ubi->fm_wl_pool.size);
1166	fmpl_wl->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
1167
1168	for (i = 0; i < ubi->fm_wl_pool.size; i++) {
1169		fmpl_wl->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
1170		set_seen(ubi, ubi->fm_wl_pool.pebs[i], seen_pebs);
1171	}
1172
1173	ubi_for_each_free_peb(ubi, wl_e, tmp_rb) {
1174		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1175
1176		fec->pnum = cpu_to_be32(wl_e->pnum);
1177		set_seen(ubi, wl_e->pnum, seen_pebs);
1178		fec->ec = cpu_to_be32(wl_e->ec);
1179
1180		free_peb_count++;
1181		fm_pos += sizeof(*fec);
1182		ubi_assert(fm_pos <= ubi->fm_size);
1183	}
1184	fmh->free_peb_count = cpu_to_be32(free_peb_count);
1185
1186	ubi_for_each_used_peb(ubi, wl_e, tmp_rb) {
1187		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1188
1189		fec->pnum = cpu_to_be32(wl_e->pnum);
1190		set_seen(ubi, wl_e->pnum, seen_pebs);
1191		fec->ec = cpu_to_be32(wl_e->ec);
1192
1193		used_peb_count++;
1194		fm_pos += sizeof(*fec);
1195		ubi_assert(fm_pos <= ubi->fm_size);
1196	}
1197
1198	ubi_for_each_protected_peb(ubi, i, wl_e) {
1199		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1200
1201		fec->pnum = cpu_to_be32(wl_e->pnum);
1202		set_seen(ubi, wl_e->pnum, seen_pebs);
1203		fec->ec = cpu_to_be32(wl_e->ec);
1204
1205		used_peb_count++;
1206		fm_pos += sizeof(*fec);
1207		ubi_assert(fm_pos <= ubi->fm_size);
1208	}
1209	fmh->used_peb_count = cpu_to_be32(used_peb_count);
1210
1211	ubi_for_each_scrub_peb(ubi, wl_e, tmp_rb) {
1212		fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1213
1214		fec->pnum = cpu_to_be32(wl_e->pnum);
1215		set_seen(ubi, wl_e->pnum, seen_pebs);
1216		fec->ec = cpu_to_be32(wl_e->ec);
1217
1218		scrub_peb_count++;
1219		fm_pos += sizeof(*fec);
1220		ubi_assert(fm_pos <= ubi->fm_size);
1221	}
1222	fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
1223
1224
1225	list_for_each_entry(ubi_wrk, &ubi->works, list) {
1226		if (ubi_is_erase_work(ubi_wrk)) {
1227			wl_e = ubi_wrk->e;
1228			ubi_assert(wl_e);
1229
1230			fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1231
1232			fec->pnum = cpu_to_be32(wl_e->pnum);
1233			set_seen(ubi, wl_e->pnum, seen_pebs);
1234			fec->ec = cpu_to_be32(wl_e->ec);
1235
1236			erase_peb_count++;
1237			fm_pos += sizeof(*fec);
1238			ubi_assert(fm_pos <= ubi->fm_size);
1239		}
1240	}
1241	fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
1242
1243	for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
1244		vol = ubi->volumes[i];
1245
1246		if (!vol)
1247			continue;
1248
1249		vol_count++;
1250
1251		fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
1252		fm_pos += sizeof(*fvh);
1253		ubi_assert(fm_pos <= ubi->fm_size);
1254
1255		fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
1256		fvh->vol_id = cpu_to_be32(vol->vol_id);
1257		fvh->vol_type = vol->vol_type;
1258		fvh->used_ebs = cpu_to_be32(vol->used_ebs);
1259		fvh->data_pad = cpu_to_be32(vol->data_pad);
1260		fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
1261
1262		ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
1263			vol->vol_type == UBI_STATIC_VOLUME);
1264
1265		feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
1266		fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
1267		ubi_assert(fm_pos <= ubi->fm_size);
1268
1269		for (j = 0; j < vol->reserved_pebs; j++)
1270			feba->pnum[j] = cpu_to_be32(vol->eba_tbl[j]);
 
 
 
 
1271
1272		feba->reserved_pebs = cpu_to_be32(j);
1273		feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
1274	}
1275	fmh->vol_count = cpu_to_be32(vol_count);
1276	fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
1277
1278	avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1279	avhdr->lnum = 0;
1280
1281	spin_unlock(&ubi->wl_lock);
1282	spin_unlock(&ubi->volumes_lock);
1283
1284	dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
1285	ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avhdr);
1286	if (ret) {
1287		ubi_err(ubi, "unable to write vid_hdr to fastmap SB!");
1288		goto out_kfree;
1289	}
1290
1291	for (i = 0; i < new_fm->used_blocks; i++) {
1292		fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
1293		set_seen(ubi, new_fm->e[i]->pnum, seen_pebs);
1294		fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
1295	}
1296
1297	fmsb->data_crc = 0;
1298	fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
1299					   ubi->fm_size));
1300
1301	for (i = 1; i < new_fm->used_blocks; i++) {
1302		dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1303		dvhdr->lnum = cpu_to_be32(i);
1304		dbg_bld("writing fastmap data to PEB %i sqnum %llu",
1305			new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
1306		ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvhdr);
1307		if (ret) {
1308			ubi_err(ubi, "unable to write vid_hdr to PEB %i!",
1309				new_fm->e[i]->pnum);
1310			goto out_kfree;
1311		}
1312	}
1313
1314	for (i = 0; i < new_fm->used_blocks; i++) {
1315		ret = ubi_io_write(ubi, fm_raw + (i * ubi->leb_size),
1316			new_fm->e[i]->pnum, ubi->leb_start, ubi->leb_size);
1317		if (ret) {
1318			ubi_err(ubi, "unable to write fastmap to PEB %i!",
1319				new_fm->e[i]->pnum);
1320			goto out_kfree;
1321		}
1322	}
1323
1324	ubi_assert(new_fm);
1325	ubi->fm = new_fm;
1326
1327	ret = self_check_seen(ubi, seen_pebs);
1328	dbg_bld("fastmap written!");
1329
1330out_kfree:
1331	ubi_free_vid_hdr(ubi, avhdr);
1332	ubi_free_vid_hdr(ubi, dvhdr);
1333	free_seen(seen_pebs);
 
 
 
 
 
1334out:
1335	return ret;
1336}
1337
1338/**
1339 * erase_block - Manually erase a PEB.
1340 * @ubi: UBI device object
1341 * @pnum: PEB to be erased
1342 *
1343 * Returns the new EC value on success, < 0 indicates an internal error.
1344 */
1345static int erase_block(struct ubi_device *ubi, int pnum)
1346{
1347	int ret;
1348	struct ubi_ec_hdr *ec_hdr;
1349	long long ec;
1350
1351	ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1352	if (!ec_hdr)
1353		return -ENOMEM;
1354
1355	ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
1356	if (ret < 0)
1357		goto out;
1358	else if (ret && ret != UBI_IO_BITFLIPS) {
1359		ret = -EINVAL;
1360		goto out;
1361	}
1362
1363	ret = ubi_io_sync_erase(ubi, pnum, 0);
1364	if (ret < 0)
1365		goto out;
1366
1367	ec = be64_to_cpu(ec_hdr->ec);
1368	ec += ret;
1369	if (ec > UBI_MAX_ERASECOUNTER) {
1370		ret = -EINVAL;
1371		goto out;
1372	}
1373
1374	ec_hdr->ec = cpu_to_be64(ec);
1375	ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
1376	if (ret < 0)
1377		goto out;
1378
1379	ret = ec;
1380out:
1381	kfree(ec_hdr);
1382	return ret;
1383}
1384
1385/**
1386 * invalidate_fastmap - destroys a fastmap.
1387 * @ubi: UBI device object
1388 *
1389 * This function ensures that upon next UBI attach a full scan
1390 * is issued. We need this if UBI is about to write a new fastmap
1391 * but is unable to do so. In this case we have two options:
1392 * a) Make sure that the current fastmap will not be usued upon
1393 * attach time and contine or b) fall back to RO mode to have the
1394 * current fastmap in a valid state.
1395 * Returns 0 on success, < 0 indicates an internal error.
1396 */
1397static int invalidate_fastmap(struct ubi_device *ubi)
1398{
1399	int ret;
1400	struct ubi_fastmap_layout *fm;
1401	struct ubi_wl_entry *e;
1402	struct ubi_vid_hdr *vh = NULL;
 
1403
1404	if (!ubi->fm)
1405		return 0;
1406
1407	ubi->fm = NULL;
1408
1409	ret = -ENOMEM;
1410	fm = kzalloc(sizeof(*fm), GFP_KERNEL);
1411	if (!fm)
1412		goto out;
1413
1414	vh = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1415	if (!vh)
1416		goto out_free_fm;
1417
 
 
1418	ret = -ENOSPC;
1419	e = ubi_wl_get_fm_peb(ubi, 1);
1420	if (!e)
1421		goto out_free_fm;
1422
1423	/*
1424	 * Create fake fastmap such that UBI will fall back
1425	 * to scanning mode.
1426	 */
1427	vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1428	ret = ubi_io_write_vid_hdr(ubi, e->pnum, vh);
1429	if (ret < 0) {
1430		ubi_wl_put_fm_peb(ubi, e, 0, 0);
1431		goto out_free_fm;
1432	}
1433
1434	fm->used_blocks = 1;
1435	fm->e[0] = e;
1436
1437	ubi->fm = fm;
1438
1439out:
1440	ubi_free_vid_hdr(ubi, vh);
1441	return ret;
1442
1443out_free_fm:
1444	kfree(fm);
1445	goto out;
1446}
1447
1448/**
1449 * return_fm_pebs - returns all PEBs used by a fastmap back to the
1450 * WL sub-system.
1451 * @ubi: UBI device object
1452 * @fm: fastmap layout object
1453 */
1454static void return_fm_pebs(struct ubi_device *ubi,
1455			   struct ubi_fastmap_layout *fm)
1456{
1457	int i;
1458
1459	if (!fm)
1460		return;
1461
1462	for (i = 0; i < fm->used_blocks; i++) {
1463		if (fm->e[i]) {
1464			ubi_wl_put_fm_peb(ubi, fm->e[i], i,
1465					  fm->to_be_tortured[i]);
1466			fm->e[i] = NULL;
1467		}
1468	}
1469}
1470
1471/**
1472 * ubi_update_fastmap - will be called by UBI if a volume changes or
1473 * a fastmap pool becomes full.
1474 * @ubi: UBI device object
1475 *
1476 * Returns 0 on success, < 0 indicates an internal error.
1477 */
1478int ubi_update_fastmap(struct ubi_device *ubi)
1479{
1480	int ret, i, j;
1481	struct ubi_fastmap_layout *new_fm, *old_fm;
1482	struct ubi_wl_entry *tmp_e;
1483
1484	down_write(&ubi->fm_protect);
 
 
1485
1486	ubi_refill_pools(ubi);
1487
1488	if (ubi->ro_mode || ubi->fm_disabled) {
 
 
1489		up_write(&ubi->fm_protect);
1490		return 0;
1491	}
1492
1493	ret = ubi_ensure_anchor_pebs(ubi);
1494	if (ret) {
1495		up_write(&ubi->fm_protect);
1496		return ret;
1497	}
1498
1499	new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
1500	if (!new_fm) {
 
 
1501		up_write(&ubi->fm_protect);
1502		return -ENOMEM;
1503	}
1504
1505	new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1506	old_fm = ubi->fm;
1507	ubi->fm = NULL;
1508
1509	if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1510		ubi_err(ubi, "fastmap too large");
1511		ret = -ENOSPC;
1512		goto err;
1513	}
1514
1515	for (i = 1; i < new_fm->used_blocks; i++) {
1516		spin_lock(&ubi->wl_lock);
1517		tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1518		spin_unlock(&ubi->wl_lock);
1519
1520		if (!tmp_e) {
1521			if (old_fm && old_fm->e[i]) {
1522				ret = erase_block(ubi, old_fm->e[i]->pnum);
1523				if (ret < 0) {
1524					ubi_err(ubi, "could not erase old fastmap PEB");
1525
1526					for (j = 1; j < i; j++) {
1527						ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1528								  j, 0);
1529						new_fm->e[j] = NULL;
1530					}
1531					goto err;
1532				}
1533				new_fm->e[i] = old_fm->e[i];
1534				old_fm->e[i] = NULL;
1535			} else {
1536				ubi_err(ubi, "could not get any free erase block");
1537
1538				for (j = 1; j < i; j++) {
1539					ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1540					new_fm->e[j] = NULL;
1541				}
1542
1543				ret = -ENOSPC;
1544				goto err;
1545			}
1546		} else {
1547			new_fm->e[i] = tmp_e;
1548
1549			if (old_fm && old_fm->e[i]) {
1550				ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1551						  old_fm->to_be_tortured[i]);
1552				old_fm->e[i] = NULL;
1553			}
1554		}
1555	}
1556
1557	/* Old fastmap is larger than the new one */
1558	if (old_fm && new_fm->used_blocks < old_fm->used_blocks) {
1559		for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) {
1560			ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1561					  old_fm->to_be_tortured[i]);
1562			old_fm->e[i] = NULL;
1563		}
1564	}
1565
1566	spin_lock(&ubi->wl_lock);
1567	tmp_e = ubi_wl_get_fm_peb(ubi, 1);
 
1568	spin_unlock(&ubi->wl_lock);
1569
1570	if (old_fm) {
1571		/* no fresh anchor PEB was found, reuse the old one */
1572		if (!tmp_e) {
1573			ret = erase_block(ubi, old_fm->e[0]->pnum);
1574			if (ret < 0) {
1575				ubi_err(ubi, "could not erase old anchor PEB");
1576
1577				for (i = 1; i < new_fm->used_blocks; i++) {
1578					ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1579							  i, 0);
1580					new_fm->e[i] = NULL;
1581				}
1582				goto err;
1583			}
1584			new_fm->e[0] = old_fm->e[0];
1585			new_fm->e[0]->ec = ret;
1586			old_fm->e[0] = NULL;
1587		} else {
1588			/* we've got a new anchor PEB, return the old one */
1589			ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1590					  old_fm->to_be_tortured[0]);
1591			new_fm->e[0] = tmp_e;
1592			old_fm->e[0] = NULL;
1593		}
1594	} else {
1595		if (!tmp_e) {
1596			ubi_err(ubi, "could not find any anchor PEB");
1597
1598			for (i = 1; i < new_fm->used_blocks; i++) {
1599				ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1600				new_fm->e[i] = NULL;
1601			}
1602
1603			ret = -ENOSPC;
1604			goto err;
1605		}
1606		new_fm->e[0] = tmp_e;
1607	}
1608
1609	down_write(&ubi->work_sem);
1610	down_write(&ubi->fm_eba_sem);
1611	ret = ubi_write_fastmap(ubi, new_fm);
1612	up_write(&ubi->fm_eba_sem);
1613	up_write(&ubi->work_sem);
1614
1615	if (ret)
1616		goto err;
1617
1618out_unlock:
 
 
1619	up_write(&ubi->fm_protect);
1620	kfree(old_fm);
 
 
 
1621	return ret;
1622
1623err:
1624	ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret);
1625
1626	ret = invalidate_fastmap(ubi);
1627	if (ret < 0) {
1628		ubi_err(ubi, "Unable to invalidiate current fastmap!");
1629		ubi_ro_mode(ubi);
1630	} else {
1631		return_fm_pebs(ubi, old_fm);
1632		return_fm_pebs(ubi, new_fm);
1633		ret = 0;
1634	}
1635
1636	kfree(new_fm);
1637	goto out_unlock;
1638}