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path: root/drivers/mtd/ubi/fastmap.c
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Diffstat (limited to 'drivers/mtd/ubi/fastmap.c')
-rw-r--r--drivers/mtd/ubi/fastmap.c1537
1 files changed, 1537 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
new file mode 100644
index 000000000000..1a5f53c090d4
--- /dev/null
+++ b/drivers/mtd/ubi/fastmap.c
@@ -0,0 +1,1537 @@
+/*
+ * Copyright (c) 2012 Linutronix GmbH
+ * Author: Richard Weinberger <richard@nod.at>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ */
+
+#include <linux/crc32.h>
+#include "ubi.h"
+
+/**
+ * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
+ * @ubi: UBI device description object
+ */
+size_t ubi_calc_fm_size(struct ubi_device *ubi)
+{
+ size_t size;
+
+ size = sizeof(struct ubi_fm_hdr) + \
+ sizeof(struct ubi_fm_scan_pool) + \
+ sizeof(struct ubi_fm_scan_pool) + \
+ (ubi->peb_count * sizeof(struct ubi_fm_ec)) + \
+ (sizeof(struct ubi_fm_eba) + \
+ (ubi->peb_count * sizeof(__be32))) + \
+ sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
+ return roundup(size, ubi->leb_size);
+}
+
+
+/**
+ * new_fm_vhdr - allocate a new volume header for fastmap usage.
+ * @ubi: UBI device description object
+ * @vol_id: the VID of the new header
+ *
+ * Returns a new struct ubi_vid_hdr on success.
+ * NULL indicates out of memory.
+ */
+static struct ubi_vid_hdr *new_fm_vhdr(struct ubi_device *ubi, int vol_id)
+{
+ struct ubi_vid_hdr *new;
+
+ new = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
+ if (!new)
+ goto out;
+
+ new->vol_type = UBI_VID_DYNAMIC;
+ new->vol_id = cpu_to_be32(vol_id);
+
+ /* UBI implementations without fastmap support have to delete the
+ * fastmap.
+ */
+ new->compat = UBI_COMPAT_DELETE;
+
+out:
+ return new;
+}
+
+/**
+ * add_aeb - create and add a attach erase block to a given list.
+ * @ai: UBI attach info object
+ * @list: the target list
+ * @pnum: PEB number of the new attach erase block
+ * @ec: erease counter of the new LEB
+ * @scrub: scrub this PEB after attaching
+ *
+ * Returns 0 on success, < 0 indicates an internal error.
+ */
+static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
+ int pnum, int ec, int scrub)
+{
+ struct ubi_ainf_peb *aeb;
+
+ aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL);
+ if (!aeb)
+ return -ENOMEM;
+
+ aeb->pnum = pnum;
+ aeb->ec = ec;
+ aeb->lnum = -1;
+ aeb->scrub = scrub;
+ aeb->copy_flag = aeb->sqnum = 0;
+
+ ai->ec_sum += aeb->ec;
+ ai->ec_count++;
+
+ if (ai->max_ec < aeb->ec)
+ ai->max_ec = aeb->ec;
+
+ if (ai->min_ec > aeb->ec)
+ ai->min_ec = aeb->ec;
+
+ list_add_tail(&aeb->u.list, list);
+
+ return 0;
+}
+
+/**
+ * add_vol - create and add a new volume to ubi_attach_info.
+ * @ai: ubi_attach_info object
+ * @vol_id: VID of the new volume
+ * @used_ebs: number of used EBS
+ * @data_pad: data padding value of the new volume
+ * @vol_type: volume type
+ * @last_eb_bytes: number of bytes in the last LEB
+ *
+ * Returns the new struct ubi_ainf_volume on success.
+ * NULL indicates an error.
+ */
+static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
+ int used_ebs, int data_pad, u8 vol_type,
+ int last_eb_bytes)
+{
+ struct ubi_ainf_volume *av;
+ struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
+
+ while (*p) {
+ parent = *p;
+ av = rb_entry(parent, struct ubi_ainf_volume, rb);
+
+ if (vol_id > av->vol_id)
+ p = &(*p)->rb_left;
+ else if (vol_id > av->vol_id)
+ p = &(*p)->rb_right;
+ }
+
+ av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
+ if (!av)
+ goto out;
+
+ av->highest_lnum = av->leb_count = 0;
+ av->vol_id = vol_id;
+ av->used_ebs = used_ebs;
+ av->data_pad = data_pad;
+ av->last_data_size = last_eb_bytes;
+ av->compat = 0;
+ av->vol_type = vol_type;
+ av->root = RB_ROOT;
+
+ dbg_bld("found volume (ID %i)", vol_id);
+
+ rb_link_node(&av->rb, parent, p);
+ rb_insert_color(&av->rb, &ai->volumes);
+
+out:
+ return av;
+}
+
+/**
+ * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
+ * from it's original list.
+ * @ai: ubi_attach_info object
+ * @aeb: the to be assigned SEB
+ * @av: target scan volume
+ */
+static void assign_aeb_to_av(struct ubi_attach_info *ai,
+ struct ubi_ainf_peb *aeb,
+ struct ubi_ainf_volume *av)
+{
+ struct ubi_ainf_peb *tmp_aeb;
+ struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
+
+ p = &av->root.rb_node;
+ while (*p) {
+ parent = *p;
+
+ tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
+ if (aeb->lnum != tmp_aeb->lnum) {
+ if (aeb->lnum < tmp_aeb->lnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+
+ continue;
+ } else
+ break;
+ }
+
+ list_del(&aeb->u.list);
+ av->leb_count++;
+
+ rb_link_node(&aeb->u.rb, parent, p);
+ rb_insert_color(&aeb->u.rb, &av->root);
+}
+
+/**
+ * update_vol - inserts or updates a LEB which was found a pool.
+ * @ubi: the UBI device object
+ * @ai: attach info object
+ * @av: the volume this LEB belongs to
+ * @new_vh: the volume header derived from new_aeb
+ * @new_aeb: the AEB to be examined
+ *
+ * Returns 0 on success, < 0 indicates an internal error.
+ */
+static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
+ struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
+ struct ubi_ainf_peb *new_aeb)
+{
+ struct rb_node **p = &av->root.rb_node, *parent = NULL;
+ struct ubi_ainf_peb *aeb, *victim;
+ int cmp_res;
+
+ while (*p) {
+ parent = *p;
+ aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
+
+ if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
+ if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+
+ continue;
+ }
+
+ /* This case can happen if the fastmap gets written
+ * because of a volume change (creation, deletion, ..).
+ * Then a PEB can be within the persistent EBA and the pool.
+ */
+ if (aeb->pnum == new_aeb->pnum) {
+ ubi_assert(aeb->lnum == new_aeb->lnum);
+ kmem_cache_free(ai->aeb_slab_cache, new_aeb);
+
+ return 0;
+ }
+
+ cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
+ if (cmp_res < 0)
+ return cmp_res;
+
+ /* new_aeb is newer */
+ if (cmp_res & 1) {
+ victim = kmem_cache_alloc(ai->aeb_slab_cache,
+ GFP_KERNEL);
+ if (!victim)
+ return -ENOMEM;
+
+ victim->ec = aeb->ec;
+ victim->pnum = aeb->pnum;
+ list_add_tail(&victim->u.list, &ai->erase);
+
+ if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
+ av->last_data_size = \
+ be32_to_cpu(new_vh->data_size);
+
+ dbg_bld("vol %i: AEB %i's PEB %i is the newer",
+ av->vol_id, aeb->lnum, new_aeb->pnum);
+
+ aeb->ec = new_aeb->ec;
+ aeb->pnum = new_aeb->pnum;
+ aeb->copy_flag = new_vh->copy_flag;
+ aeb->scrub = new_aeb->scrub;
+ kmem_cache_free(ai->aeb_slab_cache, new_aeb);
+
+ /* new_aeb is older */
+ } else {
+ dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
+ av->vol_id, aeb->lnum, new_aeb->pnum);
+ list_add_tail(&new_aeb->u.list, &ai->erase);
+ }
+
+ return 0;
+ }
+ /* This LEB is new, let's add it to the volume */
+
+ if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
+ av->highest_lnum = be32_to_cpu(new_vh->lnum);
+ av->last_data_size = be32_to_cpu(new_vh->data_size);
+ }
+
+ if (av->vol_type == UBI_STATIC_VOLUME)
+ av->used_ebs = be32_to_cpu(new_vh->used_ebs);
+
+ av->leb_count++;
+
+ rb_link_node(&new_aeb->u.rb, parent, p);
+ rb_insert_color(&new_aeb->u.rb, &av->root);
+
+ return 0;
+}
+
+/**
+ * process_pool_aeb - we found a non-empty PEB in a pool.
+ * @ubi: UBI device object
+ * @ai: attach info object
+ * @new_vh: the volume header derived from new_aeb
+ * @new_aeb: the AEB to be examined
+ *
+ * Returns 0 on success, < 0 indicates an internal error.
+ */
+static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
+ struct ubi_vid_hdr *new_vh,
+ struct ubi_ainf_peb *new_aeb)
+{
+ struct ubi_ainf_volume *av, *tmp_av = NULL;
+ struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
+ int found = 0;
+
+ if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID ||
+ be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {
+ kmem_cache_free(ai->aeb_slab_cache, new_aeb);
+
+ return 0;
+ }
+
+ /* Find the volume this SEB belongs to */
+ while (*p) {
+ parent = *p;
+ tmp_av = rb_entry(parent, struct ubi_ainf_volume, rb);
+
+ if (be32_to_cpu(new_vh->vol_id) > tmp_av->vol_id)
+ p = &(*p)->rb_left;
+ else if (be32_to_cpu(new_vh->vol_id) < tmp_av->vol_id)
+ p = &(*p)->rb_right;
+ else {
+ found = 1;
+ break;
+ }
+ }
+
+ if (found)
+ av = tmp_av;
+ else {
+ ubi_err("orphaned volume in fastmap pool!");
+ return UBI_BAD_FASTMAP;
+ }
+
+ ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);
+
+ return update_vol(ubi, ai, av, new_vh, new_aeb);
+}
+
+/**
+ * unmap_peb - unmap a PEB.
+ * If fastmap detects a free PEB in the pool it has to check whether
+ * this PEB has been unmapped after writing the fastmap.
+ *
+ * @ai: UBI attach info object
+ * @pnum: The PEB to be unmapped
+ */
+static void unmap_peb(struct ubi_attach_info *ai, int pnum)
+{
+ struct ubi_ainf_volume *av;
+ struct rb_node *node, *node2;
+ struct ubi_ainf_peb *aeb;
+
+ for (node = rb_first(&ai->volumes); node; node = rb_next(node)) {
+ av = rb_entry(node, struct ubi_ainf_volume, rb);
+
+ for (node2 = rb_first(&av->root); node2;
+ node2 = rb_next(node2)) {
+ aeb = rb_entry(node2, struct ubi_ainf_peb, u.rb);
+ if (aeb->pnum == pnum) {
+ rb_erase(&aeb->u.rb, &av->root);
+ kmem_cache_free(ai->aeb_slab_cache, aeb);
+ return;
+ }
+ }
+ }
+}
+
+/**
+ * scan_pool - scans a pool for changed (no longer empty PEBs).
+ * @ubi: UBI device object
+ * @ai: attach info object
+ * @pebs: an array of all PEB numbers in the to be scanned pool
+ * @pool_size: size of the pool (number of entries in @pebs)
+ * @max_sqnum: pointer to the maximal sequence number
+ * @eba_orphans: list of PEBs which need to be scanned
+ * @free: list of PEBs which are most likely free (and go into @ai->free)
+ *
+ * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
+ * < 0 indicates an internal error.
+ */
+static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
+ int *pebs, int pool_size, unsigned long long *max_sqnum,
+ struct list_head *eba_orphans, struct list_head *free)
+{
+ struct ubi_vid_hdr *vh;
+ struct ubi_ec_hdr *ech;
+ struct ubi_ainf_peb *new_aeb, *tmp_aeb;
+ int i, pnum, err, found_orphan, ret = 0;
+
+ ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (!ech)
+ return -ENOMEM;
+
+ vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
+ if (!vh) {
+ kfree(ech);
+ return -ENOMEM;
+ }
+
+ dbg_bld("scanning fastmap pool: size = %i", pool_size);
+
+ /*
+ * Now scan all PEBs in the pool to find changes which have been made
+ * after the creation of the fastmap
+ */
+ for (i = 0; i < pool_size; i++) {
+ int scrub = 0;
+
+ pnum = be32_to_cpu(pebs[i]);
+
+ if (ubi_io_is_bad(ubi, pnum)) {
+ ubi_err("bad PEB in fastmap pool!");
+ ret = UBI_BAD_FASTMAP;
+ goto out;
+ }
+
+ err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
+ if (err && err != UBI_IO_BITFLIPS) {
+ ubi_err("unable to read EC header! PEB:%i err:%i",
+ pnum, err);
+ ret = err > 0 ? UBI_BAD_FASTMAP : err;
+ goto out;
+ } else if (ret == UBI_IO_BITFLIPS)
+ scrub = 1;
+
+ if (be32_to_cpu(ech->image_seq) != ubi->image_seq) {
+ ubi_err("bad image seq: 0x%x, expected: 0x%x",
+ be32_to_cpu(ech->image_seq), ubi->image_seq);
+ err = UBI_BAD_FASTMAP;
+ goto out;
+ }
+
+ err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
+ if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
+ unsigned long long ec = be64_to_cpu(ech->ec);
+ unmap_peb(ai, pnum);
+ dbg_bld("Adding PEB to free: %i", pnum);
+ if (err == UBI_IO_FF_BITFLIPS)
+ add_aeb(ai, free, pnum, ec, 1);
+ else
+ add_aeb(ai, free, pnum, ec, 0);
+ continue;
+ } else if (err == 0 || err == UBI_IO_BITFLIPS) {
+ dbg_bld("Found non empty PEB:%i in pool", pnum);
+
+ if (err == UBI_IO_BITFLIPS)
+ scrub = 1;
+
+ found_orphan = 0;
+ list_for_each_entry(tmp_aeb, eba_orphans, u.list) {
+ if (tmp_aeb->pnum == pnum) {
+ found_orphan = 1;
+ break;
+ }
+ }
+ if (found_orphan) {
+ kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
+ list_del(&tmp_aeb->u.list);
+ }
+
+ new_aeb = kmem_cache_alloc(ai->aeb_slab_cache,
+ GFP_KERNEL);
+ if (!new_aeb) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ new_aeb->ec = be64_to_cpu(ech->ec);
+ new_aeb->pnum = pnum;
+ new_aeb->lnum = be32_to_cpu(vh->lnum);
+ new_aeb->sqnum = be64_to_cpu(vh->sqnum);
+ new_aeb->copy_flag = vh->copy_flag;
+ new_aeb->scrub = scrub;
+
+ if (*max_sqnum < new_aeb->sqnum)
+ *max_sqnum = new_aeb->sqnum;
+
+ err = process_pool_aeb(ubi, ai, vh, new_aeb);
+ if (err) {
+ ret = err > 0 ? UBI_BAD_FASTMAP : err;
+ goto out;
+ }
+ } else {
+ /* We are paranoid and fall back to scanning mode */
+ ubi_err("fastmap pool PEBs contains damaged PEBs!");
+ ret = err > 0 ? UBI_BAD_FASTMAP : err;
+ goto out;
+ }
+
+ }
+
+out:
+ ubi_free_vid_hdr(ubi, vh);
+ kfree(ech);
+ return ret;
+}
+
+/**
+ * count_fastmap_pebs - Counts the PEBs found by fastmap.
+ * @ai: The UBI attach info object
+ */
+static int count_fastmap_pebs(struct ubi_attach_info *ai)
+{
+ struct ubi_ainf_peb *aeb;
+ struct ubi_ainf_volume *av;
+ struct rb_node *rb1, *rb2;
+ int n = 0;
+
+ list_for_each_entry(aeb, &ai->erase, u.list)
+ n++;
+
+ list_for_each_entry(aeb, &ai->free, u.list)
+ n++;
+
+ ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
+ ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
+ n++;
+
+ return n;
+}
+
+/**
+ * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
+ * @ubi: UBI device object
+ * @ai: UBI attach info object
+ * @fm: the fastmap to be attached
+ *
+ * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
+ * < 0 indicates an internal error.
+ */
+static int ubi_attach_fastmap(struct ubi_device *ubi,
+ struct ubi_attach_info *ai,
+ struct ubi_fastmap_layout *fm)
+{
+ struct list_head used, eba_orphans, free;
+ struct ubi_ainf_volume *av;
+ struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
+ struct ubi_ec_hdr *ech;
+ struct ubi_fm_sb *fmsb;
+ struct ubi_fm_hdr *fmhdr;
+ struct ubi_fm_scan_pool *fmpl1, *fmpl2;
+ struct ubi_fm_ec *fmec;
+ struct ubi_fm_volhdr *fmvhdr;
+ struct ubi_fm_eba *fm_eba;
+ int ret, i, j, pool_size, wl_pool_size;
+ size_t fm_pos = 0, fm_size = ubi->fm_size;
+ unsigned long long max_sqnum = 0;
+ void *fm_raw = ubi->fm_buf;
+
+ INIT_LIST_HEAD(&used);
+ INIT_LIST_HEAD(&free);
+ INIT_LIST_HEAD(&eba_orphans);
+ INIT_LIST_HEAD(&ai->corr);
+ INIT_LIST_HEAD(&ai->free);
+ INIT_LIST_HEAD(&ai->erase);
+ INIT_LIST_HEAD(&ai->alien);
+ ai->volumes = RB_ROOT;
+ ai->min_ec = UBI_MAX_ERASECOUNTER;
+
+ ai->aeb_slab_cache = kmem_cache_create("ubi_ainf_peb_slab",
+ sizeof(struct ubi_ainf_peb),
+ 0, 0, NULL);
+ if (!ai->aeb_slab_cache) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ fmsb = (struct ubi_fm_sb *)(fm_raw);
+ ai->max_sqnum = fmsb->sqnum;
+ fm_pos += sizeof(struct ubi_fm_sb);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmhdr);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
+ ubi_err("bad fastmap header magic: 0x%x, expected: 0x%x",
+ be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
+ goto fail_bad;
+ }
+
+ fmpl1 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmpl1);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+ if (be32_to_cpu(fmpl1->magic) != UBI_FM_POOL_MAGIC) {
+ ubi_err("bad fastmap pool magic: 0x%x, expected: 0x%x",
+ be32_to_cpu(fmpl1->magic), UBI_FM_POOL_MAGIC);
+ goto fail_bad;
+ }
+
+ fmpl2 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmpl2);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+ if (be32_to_cpu(fmpl2->magic) != UBI_FM_POOL_MAGIC) {
+ ubi_err("bad fastmap pool magic: 0x%x, expected: 0x%x",
+ be32_to_cpu(fmpl2->magic), UBI_FM_POOL_MAGIC);
+ goto fail_bad;
+ }
+
+ pool_size = be16_to_cpu(fmpl1->size);
+ wl_pool_size = be16_to_cpu(fmpl2->size);
+ fm->max_pool_size = be16_to_cpu(fmpl1->max_size);
+ fm->max_wl_pool_size = be16_to_cpu(fmpl2->max_size);
+
+ if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
+ ubi_err("bad pool size: %i", pool_size);
+ goto fail_bad;
+ }
+
+ if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
+ ubi_err("bad WL pool size: %i", wl_pool_size);
+ goto fail_bad;
+ }
+
+
+ if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
+ fm->max_pool_size < 0) {
+ ubi_err("bad maximal pool size: %i", fm->max_pool_size);
+ goto fail_bad;
+ }
+
+ if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
+ fm->max_wl_pool_size < 0) {
+ ubi_err("bad maximal WL pool size: %i", fm->max_wl_pool_size);
+ goto fail_bad;
+ }
+
+ /* read EC values from free list */
+ for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
+ fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmec);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
+ be32_to_cpu(fmec->ec), 0);
+ }
+
+ /* read EC values from used list */
+ for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
+ fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmec);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
+ be32_to_cpu(fmec->ec), 0);
+ }
+
+ /* read EC values from scrub list */
+ for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
+ fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmec);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
+ be32_to_cpu(fmec->ec), 1);
+ }
+
+ /* read EC values from erase list */
+ for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
+ fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmec);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
+ be32_to_cpu(fmec->ec), 1);
+ }
+
+ ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
+ ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
+
+ /* Iterate over all volumes and read their EBA table */
+ for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
+ fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmvhdr);
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
+ ubi_err("bad fastmap vol header magic: 0x%x, " \
+ "expected: 0x%x",
+ be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
+ goto fail_bad;
+ }
+
+ av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
+ be32_to_cpu(fmvhdr->used_ebs),
+ be32_to_cpu(fmvhdr->data_pad),
+ fmvhdr->vol_type,
+ be32_to_cpu(fmvhdr->last_eb_bytes));
+
+ if (!av)
+ goto fail_bad;
+
+ ai->vols_found++;
+ if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
+ ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
+
+ fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fm_eba);
+ fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
+ if (fm_pos >= fm_size)
+ goto fail_bad;
+
+ if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
+ ubi_err("bad fastmap EBA header magic: 0x%x, " \
+ "expected: 0x%x",
+ be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
+ goto fail_bad;
+ }
+
+ for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
+ int pnum = be32_to_cpu(fm_eba->pnum[j]);
+
+ if ((int)be32_to_cpu(fm_eba->pnum[j]) < 0)
+ continue;
+
+ aeb = NULL;
+ list_for_each_entry(tmp_aeb, &used, u.list) {
+ if (tmp_aeb->pnum == pnum)
+ aeb = tmp_aeb;
+ }
+
+ /* This can happen if a PEB is already in an EBA known
+ * by this fastmap but the PEB itself is not in the used
+ * list.
+ * In this case the PEB can be within the fastmap pool
+ * or while writing the fastmap it was in the protection
+ * queue.
+ */
+ if (!aeb) {
+ aeb = kmem_cache_alloc(ai->aeb_slab_cache,
+ GFP_KERNEL);
+ if (!aeb) {
+ ret = -ENOMEM;
+
+ goto fail;
+ }
+
+ aeb->lnum = j;
+ aeb->pnum = be32_to_cpu(fm_eba->pnum[j]);
+ aeb->ec = -1;
+ aeb->scrub = aeb->copy_flag = aeb->sqnum = 0;
+ list_add_tail(&aeb->u.list, &eba_orphans);
+ continue;
+ }
+
+ aeb->lnum = j;
+
+ if (av->highest_lnum <= aeb->lnum)
+ av->highest_lnum = aeb->lnum;
+
+ assign_aeb_to_av(ai, aeb, av);
+
+ dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
+ aeb->pnum, aeb->lnum, av->vol_id);
+ }
+
+ ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (!ech) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &eba_orphans,
+ u.list) {
+ int err;
+
+ if (ubi_io_is_bad(ubi, tmp_aeb->pnum)) {
+ ubi_err("bad PEB in fastmap EBA orphan list");
+ ret = UBI_BAD_FASTMAP;
+ kfree(ech);
+ goto fail;
+ }
+
+ err = ubi_io_read_ec_hdr(ubi, tmp_aeb->pnum, ech, 0);
+ if (err && err != UBI_IO_BITFLIPS) {
+ ubi_err("unable to read EC header! PEB:%i " \
+ "err:%i", tmp_aeb->pnum, err);
+ ret = err > 0 ? UBI_BAD_FASTMAP : err;
+ kfree(ech);
+
+ goto fail;
+ } else if (err == UBI_IO_BITFLIPS)
+ tmp_aeb->scrub = 1;
+
+ tmp_aeb->ec = be64_to_cpu(ech->ec);
+ assign_aeb_to_av(ai, tmp_aeb, av);
+ }
+
+ kfree(ech);
+ }
+
+ ret = scan_pool(ubi, ai, fmpl1->pebs, pool_size, &max_sqnum,
+ &eba_orphans, &free);
+ if (ret)
+ goto fail;
+
+ ret = scan_pool(ubi, ai, fmpl2->pebs, wl_pool_size, &max_sqnum,
+ &eba_orphans, &free);
+ if (ret)
+ goto fail;
+
+ if (max_sqnum > ai->max_sqnum)
+ ai->max_sqnum = max_sqnum;
+
+ list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) {
+ list_del(&tmp_aeb->u.list);
+ list_add_tail(&tmp_aeb->u.list, &ai->free);
+ }
+
+ /*
+ * If fastmap is leaking PEBs (must not happen), raise a
+ * fat warning and fall back to scanning mode.
+ * We do this here because in ubi_wl_init() it's too late
+ * and we cannot fall back to scanning.
+ */
+ if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
+ ai->bad_peb_count - fm->used_blocks))
+ goto fail_bad;
+
+ return 0;
+
+fail_bad:
+ ret = UBI_BAD_FASTMAP;
+fail:
+ return ret;
+}
+
+/**
+ * ubi_scan_fastmap - scan the fastmap.
+ * @ubi: UBI device object
+ * @ai: UBI attach info to be filled
+ * @fm_anchor: The fastmap starts at this PEB
+ *
+ * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
+ * UBI_BAD_FASTMAP if one was found but is not usable.
+ * < 0 indicates an internal error.
+ */
+int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
+ int fm_anchor)
+{
+ struct ubi_fm_sb *fmsb, *fmsb2;
+ struct ubi_vid_hdr *vh;
+ struct ubi_ec_hdr *ech;
+ struct ubi_fastmap_layout *fm;
+ int i, used_blocks, pnum, ret = 0;
+ size_t fm_size;
+ __be32 crc, tmp_crc;
+ unsigned long long sqnum = 0;
+
+ mutex_lock(&ubi->fm_mutex);
+ memset(ubi->fm_buf, 0, ubi->fm_size);
+
+ fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
+ if (!fmsb) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ fm = kzalloc(sizeof(*fm), GFP_KERNEL);
+ if (!fm) {
+ ret = -ENOMEM;
+ kfree(fmsb);
+ goto out;
+ }
+
+ ret = ubi_io_read(ubi, fmsb, fm_anchor, ubi->leb_start, sizeof(*fmsb));
+ if (ret && ret != UBI_IO_BITFLIPS)
+ goto free_fm_sb;
+ else if (ret == UBI_IO_BITFLIPS)
+ fm->to_be_tortured[0] = 1;
+
+ if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
+ ubi_err("bad super block magic: 0x%x, expected: 0x%x",
+ be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
+ ret = UBI_BAD_FASTMAP;
+ goto free_fm_sb;
+ }
+
+ if (fmsb->version != UBI_FM_FMT_VERSION) {
+ ubi_err("bad fastmap version: %i, expected: %i",
+ fmsb->version, UBI_FM_FMT_VERSION);
+ ret = UBI_BAD_FASTMAP;
+ goto free_fm_sb;
+ }
+
+ used_blocks = be32_to_cpu(fmsb->used_blocks);
+ if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
+ ubi_err("number of fastmap blocks is invalid: %i", used_blocks);
+ ret = UBI_BAD_FASTMAP;
+ goto free_fm_sb;
+ }
+
+ fm_size = ubi->leb_size * used_blocks;
+ if (fm_size != ubi->fm_size) {
+ ubi_err("bad fastmap size: %zi, expected: %zi", fm_size,
+ ubi->fm_size);
+ ret = UBI_BAD_FASTMAP;
+ goto free_fm_sb;
+ }
+
+ ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (!ech) {
+ ret = -ENOMEM;
+ goto free_fm_sb;
+ }
+
+ vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
+ if (!vh) {
+ ret = -ENOMEM;
+ goto free_hdr;
+ }
+
+ for (i = 0; i < used_blocks; i++) {
+ pnum = be32_to_cpu(fmsb->block_loc[i]);
+
+ if (ubi_io_is_bad(ubi, pnum)) {
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ }
+
+ ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
+ if (ret && ret != UBI_IO_BITFLIPS) {
+ ubi_err("unable to read fastmap block# %i EC (PEB: %i)",
+ i, pnum);
+ if (ret > 0)
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ } else if (ret == UBI_IO_BITFLIPS)
+ fm->to_be_tortured[i] = 1;
+
+ if (!ubi->image_seq)
+ ubi->image_seq = be32_to_cpu(ech->image_seq);
+
+ if (be32_to_cpu(ech->image_seq) != ubi->image_seq) {
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ }
+
+ ret = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
+ if (ret && ret != UBI_IO_BITFLIPS) {
+ ubi_err("unable to read fastmap block# %i (PEB: %i)",
+ i, pnum);
+ goto free_hdr;
+ }
+
+ if (i == 0) {
+ if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
+ ubi_err("bad fastmap anchor vol_id: 0x%x," \
+ " expected: 0x%x",
+ be32_to_cpu(vh->vol_id),
+ UBI_FM_SB_VOLUME_ID);
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ }
+ } else {
+ if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
+ ubi_err("bad fastmap data vol_id: 0x%x," \
+ " expected: 0x%x",
+ be32_to_cpu(vh->vol_id),
+ UBI_FM_DATA_VOLUME_ID);
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ }
+ }
+
+ if (sqnum < be64_to_cpu(vh->sqnum))
+ sqnum = be64_to_cpu(vh->sqnum);
+
+ ret = ubi_io_read(ubi, ubi->fm_buf + (ubi->leb_size * i), pnum,
+ ubi->leb_start, ubi->leb_size);
+ if (ret && ret != UBI_IO_BITFLIPS) {
+ ubi_err("unable to read fastmap block# %i (PEB: %i, " \
+ "err: %i)", i, pnum, ret);
+ goto free_hdr;
+ }
+ }
+
+ kfree(fmsb);
+ fmsb = NULL;
+
+ fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
+ tmp_crc = be32_to_cpu(fmsb2->data_crc);
+ fmsb2->data_crc = 0;
+ crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
+ if (crc != tmp_crc) {
+ ubi_err("fastmap data CRC is invalid");
+ ubi_err("CRC should be: 0x%x, calc: 0x%x", tmp_crc, crc);
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ }
+
+ fmsb2->sqnum = sqnum;
+
+ fm->used_blocks = used_blocks;
+
+ ret = ubi_attach_fastmap(ubi, ai, fm);
+ if (ret) {
+ if (ret > 0)
+ ret = UBI_BAD_FASTMAP;
+ goto free_hdr;
+ }
+
+ for (i = 0; i < used_blocks; i++) {
+ struct ubi_wl_entry *e;
+
+ e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
+ if (!e) {
+ while (i--)
+ kfree(fm->e[i]);
+
+ ret = -ENOMEM;
+ goto free_hdr;
+ }
+
+ e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
+ e->ec = be32_to_cpu(fmsb2->block_ec[i]);
+ fm->e[i] = e;
+ }
+
+ ubi->fm = fm;
+ ubi->fm_pool.max_size = ubi->fm->max_pool_size;
+ ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
+ ubi_msg("attached by fastmap");
+ ubi_msg("fastmap pool size: %d", ubi->fm_pool.max_size);
+ ubi_msg("fastmap WL pool size: %d", ubi->fm_wl_pool.max_size);
+ ubi->fm_disabled = 0;
+
+ ubi_free_vid_hdr(ubi, vh);
+ kfree(ech);
+out:
+ mutex_unlock(&ubi->fm_mutex);
+ if (ret == UBI_BAD_FASTMAP)
+ ubi_err("Attach by fastmap failed, doing a full scan!");
+ return ret;
+
+free_hdr:
+ ubi_free_vid_hdr(ubi, vh);
+ kfree(ech);
+free_fm_sb:
+ kfree(fmsb);
+ kfree(fm);
+ goto out;
+}
+
+/**
+ * ubi_write_fastmap - writes a fastmap.
+ * @ubi: UBI device object
+ * @new_fm: the to be written fastmap
+ *
+ * Returns 0 on success, < 0 indicates an internal error.
+ */
+static int ubi_write_fastmap(struct ubi_device *ubi,
+ struct ubi_fastmap_layout *new_fm)
+{
+ size_t fm_pos = 0;
+ void *fm_raw;
+ struct ubi_fm_sb *fmsb;
+ struct ubi_fm_hdr *fmh;
+ struct ubi_fm_scan_pool *fmpl1, *fmpl2;
+ struct ubi_fm_ec *fec;
+ struct ubi_fm_volhdr *fvh;
+ struct ubi_fm_eba *feba;
+ struct rb_node *node;
+ struct ubi_wl_entry *wl_e;
+ struct ubi_volume *vol;
+ struct ubi_vid_hdr *avhdr, *dvhdr;
+ struct ubi_work *ubi_wrk;
+ int ret, i, j, free_peb_count, used_peb_count, vol_count;
+ int scrub_peb_count, erase_peb_count;
+
+ fm_raw = ubi->fm_buf;
+ memset(ubi->fm_buf, 0, ubi->fm_size);
+
+ avhdr = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
+ if (!avhdr) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ dvhdr = new_fm_vhdr(ubi, UBI_FM_DATA_VOLUME_ID);
+ if (!dvhdr) {
+ ret = -ENOMEM;
+ goto out_kfree;
+ }
+
+ spin_lock(&ubi->volumes_lock);
+ spin_lock(&ubi->wl_lock);
+
+ fmsb = (struct ubi_fm_sb *)fm_raw;
+ fm_pos += sizeof(*fmsb);
+ ubi_assert(fm_pos <= ubi->fm_size);
+
+ fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmh);
+ ubi_assert(fm_pos <= ubi->fm_size);
+
+ fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
+ fmsb->version = UBI_FM_FMT_VERSION;
+ fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
+ /* the max sqnum will be filled in while *reading* the fastmap */
+ fmsb->sqnum = 0;
+
+ fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
+ free_peb_count = 0;
+ used_peb_count = 0;
+ scrub_peb_count = 0;
+ erase_peb_count = 0;
+ vol_count = 0;
+
+ fmpl1 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmpl1);
+ fmpl1->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
+ fmpl1->size = cpu_to_be16(ubi->fm_pool.size);
+ fmpl1->max_size = cpu_to_be16(ubi->fm_pool.max_size);
+
+ for (i = 0; i < ubi->fm_pool.size; i++)
+ fmpl1->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
+
+ fmpl2 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fmpl2);
+ fmpl2->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
+ fmpl2->size = cpu_to_be16(ubi->fm_wl_pool.size);
+ fmpl2->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
+
+ for (i = 0; i < ubi->fm_wl_pool.size; i++)
+ fmpl2->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
+
+ for (node = rb_first(&ubi->free); node; node = rb_next(node)) {
+ wl_e = rb_entry(node, struct ubi_wl_entry, u.rb);
+ fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+
+ fec->pnum = cpu_to_be32(wl_e->pnum);
+ fec->ec = cpu_to_be32(wl_e->ec);
+
+ free_peb_count++;
+ fm_pos += sizeof(*fec);
+ ubi_assert(fm_pos <= ubi->fm_size);
+ }
+ fmh->free_peb_count = cpu_to_be32(free_peb_count);
+
+ for (node = rb_first(&ubi->used); node; node = rb_next(node)) {
+ wl_e = rb_entry(node, struct ubi_wl_entry, u.rb);
+ fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+
+ fec->pnum = cpu_to_be32(wl_e->pnum);
+ fec->ec = cpu_to_be32(wl_e->ec);
+
+ used_peb_count++;
+ fm_pos += sizeof(*fec);
+ ubi_assert(fm_pos <= ubi->fm_size);
+ }
+ fmh->used_peb_count = cpu_to_be32(used_peb_count);
+
+ for (node = rb_first(&ubi->scrub); node; node = rb_next(node)) {
+ wl_e = rb_entry(node, struct ubi_wl_entry, u.rb);
+ fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+
+ fec->pnum = cpu_to_be32(wl_e->pnum);
+ fec->ec = cpu_to_be32(wl_e->ec);
+
+ scrub_peb_count++;
+ fm_pos += sizeof(*fec);
+ ubi_assert(fm_pos <= ubi->fm_size);
+ }
+ fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
+
+
+ list_for_each_entry(ubi_wrk, &ubi->works, list) {
+ if (ubi_is_erase_work(ubi_wrk)) {
+ wl_e = ubi_wrk->e;
+ ubi_assert(wl_e);
+
+ fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
+
+ fec->pnum = cpu_to_be32(wl_e->pnum);
+ fec->ec = cpu_to_be32(wl_e->ec);
+
+ erase_peb_count++;
+ fm_pos += sizeof(*fec);
+ ubi_assert(fm_pos <= ubi->fm_size);
+ }
+ }
+ fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
+
+ for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
+ vol = ubi->volumes[i];
+
+ if (!vol)
+ continue;
+
+ vol_count++;
+
+ fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*fvh);
+ ubi_assert(fm_pos <= ubi->fm_size);
+
+ fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
+ fvh->vol_id = cpu_to_be32(vol->vol_id);
+ fvh->vol_type = vol->vol_type;
+ fvh->used_ebs = cpu_to_be32(vol->used_ebs);
+ fvh->data_pad = cpu_to_be32(vol->data_pad);
+ fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
+
+ ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
+ vol->vol_type == UBI_STATIC_VOLUME);
+
+ feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
+ fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
+ ubi_assert(fm_pos <= ubi->fm_size);
+
+ for (j = 0; j < vol->reserved_pebs; j++)
+ feba->pnum[j] = cpu_to_be32(vol->eba_tbl[j]);
+
+ feba->reserved_pebs = cpu_to_be32(j);
+ feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
+ }
+ fmh->vol_count = cpu_to_be32(vol_count);
+ fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
+
+ avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
+ avhdr->lnum = 0;
+
+ spin_unlock(&ubi->wl_lock);
+ spin_unlock(&ubi->volumes_lock);
+
+ dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
+ ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avhdr);
+ if (ret) {
+ ubi_err("unable to write vid_hdr to fastmap SB!");
+ goto out_kfree;
+ }
+
+ for (i = 0; i < new_fm->used_blocks; i++) {
+ fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
+ fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
+ }
+
+ fmsb->data_crc = 0;
+ fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
+ ubi->fm_size));
+
+ for (i = 1; i < new_fm->used_blocks; i++) {
+ dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
+ dvhdr->lnum = cpu_to_be32(i);
+ dbg_bld("writing fastmap data to PEB %i sqnum %llu",
+ new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
+ ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvhdr);
+ if (ret) {
+ ubi_err("unable to write vid_hdr to PEB %i!",
+ new_fm->e[i]->pnum);
+ goto out_kfree;
+ }
+ }
+
+ for (i = 0; i < new_fm->used_blocks; i++) {
+ ret = ubi_io_write(ubi, fm_raw + (i * ubi->leb_size),
+ new_fm->e[i]->pnum, ubi->leb_start, ubi->leb_size);
+ if (ret) {
+ ubi_err("unable to write fastmap to PEB %i!",
+ new_fm->e[i]->pnum);
+ goto out_kfree;
+ }
+ }
+
+ ubi_assert(new_fm);
+ ubi->fm = new_fm;
+
+ dbg_bld("fastmap written!");
+
+out_kfree:
+ ubi_free_vid_hdr(ubi, avhdr);
+ ubi_free_vid_hdr(ubi, dvhdr);
+out:
+ return ret;
+}
+
+/**
+ * erase_block - Manually erase a PEB.
+ * @ubi: UBI device object
+ * @pnum: PEB to be erased
+ *
+ * Returns the new EC value on success, < 0 indicates an internal error.
+ */
+static int erase_block(struct ubi_device *ubi, int pnum)
+{
+ int ret;
+ struct ubi_ec_hdr *ec_hdr;
+ long long ec;
+
+ ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
+ if (!ec_hdr)
+ return -ENOMEM;
+
+ ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
+ if (ret < 0)
+ goto out;
+ else if (ret && ret != UBI_IO_BITFLIPS) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = ubi_io_sync_erase(ubi, pnum, 0);
+ if (ret < 0)
+ goto out;
+
+ ec = be64_to_cpu(ec_hdr->ec);
+ ec += ret;
+ if (ec > UBI_MAX_ERASECOUNTER) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ec_hdr->ec = cpu_to_be64(ec);
+ ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
+ if (ret < 0)
+ goto out;
+
+ ret = ec;
+out:
+ kfree(ec_hdr);
+ return ret;
+}
+
+/**
+ * invalidate_fastmap - destroys a fastmap.
+ * @ubi: UBI device object
+ * @fm: the fastmap to be destroyed
+ *
+ * Returns 0 on success, < 0 indicates an internal error.
+ */
+static int invalidate_fastmap(struct ubi_device *ubi,
+ struct ubi_fastmap_layout *fm)
+{
+ int ret, i;
+ struct ubi_vid_hdr *vh;
+
+ ret = erase_block(ubi, fm->e[0]->pnum);
+ if (ret < 0)
+ return ret;
+
+ vh = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
+ if (!vh)
+ return -ENOMEM;
+
+ /* deleting the current fastmap SB is not enough, an old SB may exist,
+ * so create a (corrupted) SB such that fastmap will find it and fall
+ * back to scanning mode in any case */
+ vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
+ ret = ubi_io_write_vid_hdr(ubi, fm->e[0]->pnum, vh);
+
+ for (i = 0; i < fm->used_blocks; i++)
+ ubi_wl_put_fm_peb(ubi, fm->e[i], i, fm->to_be_tortured[i]);
+
+ return ret;
+}
+
+/**
+ * ubi_update_fastmap - will be called by UBI if a volume changes or
+ * a fastmap pool becomes full.
+ * @ubi: UBI device object
+ *
+ * Returns 0 on success, < 0 indicates an internal error.
+ */
+int ubi_update_fastmap(struct ubi_device *ubi)
+{
+ int ret, i;
+ struct ubi_fastmap_layout *new_fm, *old_fm;
+ struct ubi_wl_entry *tmp_e;
+
+ mutex_lock(&ubi->fm_mutex);
+
+ ubi_refill_pools(ubi);
+
+ if (ubi->ro_mode || ubi->fm_disabled) {
+ mutex_unlock(&ubi->fm_mutex);
+ return 0;
+ }
+
+ ret = ubi_ensure_anchor_pebs(ubi);
+ if (ret) {
+ mutex_unlock(&ubi->fm_mutex);
+ return ret;
+ }
+
+ new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
+ if (!new_fm) {
+ mutex_unlock(&ubi->fm_mutex);
+ return -ENOMEM;
+ }
+
+ new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
+
+ for (i = 0; i < new_fm->used_blocks; i++) {
+ new_fm->e[i] = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
+ if (!new_fm->e[i]) {
+ while (i--)
+ kfree(new_fm->e[i]);
+
+ kfree(new_fm);
+ mutex_unlock(&ubi->fm_mutex);
+ return -ENOMEM;
+ }
+ }
+
+ old_fm = ubi->fm;
+ ubi->fm = NULL;
+
+ if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
+ ubi_err("fastmap too large");
+ ret = -ENOSPC;
+ goto err;
+ }
+
+ for (i = 1; i < new_fm->used_blocks; i++) {
+ spin_lock(&ubi->wl_lock);
+ tmp_e = ubi_wl_get_fm_peb(ubi, 0);
+ spin_unlock(&ubi->wl_lock);
+
+ if (!tmp_e && !old_fm) {
+ int j;
+ ubi_err("could not get any free erase block");
+
+ for (j = 1; j < i; j++)
+ ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
+
+ ret = -ENOSPC;
+ goto err;
+ } else if (!tmp_e && old_fm) {
+ ret = erase_block(ubi, old_fm->e[i]->pnum);
+ if (ret < 0) {
+ int j;
+
+ for (j = 1; j < i; j++)
+ ubi_wl_put_fm_peb(ubi, new_fm->e[j],
+ j, 0);
+
+ ubi_err("could not erase old fastmap PEB");
+ goto err;
+ }
+
+ new_fm->e[i]->pnum = old_fm->e[i]->pnum;
+ new_fm->e[i]->ec = old_fm->e[i]->ec;
+ } else {
+ new_fm->e[i]->pnum = tmp_e->pnum;
+ new_fm->e[i]->ec = tmp_e->ec;
+
+ if (old_fm)
+ ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
+ old_fm->to_be_tortured[i]);
+ }
+ }
+
+ spin_lock(&ubi->wl_lock);
+ tmp_e = ubi_wl_get_fm_peb(ubi, 1);
+ spin_unlock(&ubi->wl_lock);
+
+ if (old_fm) {
+ /* no fresh anchor PEB was found, reuse the old one */
+ if (!tmp_e) {
+ ret = erase_block(ubi, old_fm->e[0]->pnum);
+ if (ret < 0) {
+ int i;
+ ubi_err("could not erase old anchor PEB");
+
+ for (i = 1; i < new_fm->used_blocks; i++)
+ ubi_wl_put_fm_peb(ubi, new_fm->e[i],
+ i, 0);
+ goto err;
+ }
+
+ new_fm->e[0]->pnum = old_fm->e[0]->pnum;
+ new_fm->e[0]->ec = ret;
+ } else {
+ /* we've got a new anchor PEB, return the old one */
+ ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
+ old_fm->to_be_tortured[0]);
+
+ new_fm->e[0]->pnum = tmp_e->pnum;
+ new_fm->e[0]->ec = tmp_e->ec;
+ }
+ } else {
+ if (!tmp_e) {
+ int i;
+ ubi_err("could not find any anchor PEB");
+
+ for (i = 1; i < new_fm->used_blocks; i++)
+ ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
+
+ ret = -ENOSPC;
+ goto err;
+ }
+
+ new_fm->e[0]->pnum = tmp_e->pnum;
+ new_fm->e[0]->ec = tmp_e->ec;
+ }
+
+ down_write(&ubi->work_sem);
+ down_write(&ubi->fm_sem);
+ ret = ubi_write_fastmap(ubi, new_fm);
+ up_write(&ubi->fm_sem);
+ up_write(&ubi->work_sem);
+
+ if (ret)
+ goto err;
+
+out_unlock:
+ mutex_unlock(&ubi->fm_mutex);
+ kfree(old_fm);
+ return ret;
+
+err:
+ kfree(new_fm);
+
+ ubi_warn("Unable to write new fastmap, err=%i", ret);
+
+ ret = 0;
+ if (old_fm) {
+ ret = invalidate_fastmap(ubi, old_fm);
+ if (ret < 0)
+ ubi_err("Unable to invalidiate current fastmap!");
+ else if (ret)
+ ret = 0;
+ }
+ goto out_unlock;
+}