diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/mtd/ubi/fastmap.c | 1699 |
1 files changed, 1699 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c new file mode 100644 index 000000000..6e95c4b14 --- /dev/null +++ b/drivers/mtd/ubi/fastmap.c @@ -0,0 +1,1699 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2012 Linutronix GmbH + * Copyright (c) 2014 sigma star gmbh + * Author: Richard Weinberger <richard@nod.at> + */ + +#include <linux/crc32.h> +#include <linux/bitmap.h> +#include "ubi.h" + +/** + * init_seen - allocate memory for used for debugging. + * @ubi: UBI device description object + */ +static inline unsigned long *init_seen(struct ubi_device *ubi) +{ + unsigned long *ret; + + if (!ubi_dbg_chk_fastmap(ubi)) + return NULL; + + ret = kcalloc(BITS_TO_LONGS(ubi->peb_count), sizeof(unsigned long), + GFP_KERNEL); + if (!ret) + return ERR_PTR(-ENOMEM); + + return ret; +} + +/** + * free_seen - free the seen logic integer array. + * @seen: integer array of @ubi->peb_count size + */ +static inline void free_seen(unsigned long *seen) +{ + kfree(seen); +} + +/** + * set_seen - mark a PEB as seen. + * @ubi: UBI device description object + * @pnum: The PEB to be makred as seen + * @seen: integer array of @ubi->peb_count size + */ +static inline void set_seen(struct ubi_device *ubi, int pnum, unsigned long *seen) +{ + if (!ubi_dbg_chk_fastmap(ubi) || !seen) + return; + + set_bit(pnum, seen); +} + +/** + * self_check_seen - check whether all PEB have been seen by fastmap. + * @ubi: UBI device description object + * @seen: integer array of @ubi->peb_count size + */ +static int self_check_seen(struct ubi_device *ubi, unsigned long *seen) +{ + int pnum, ret = 0; + + if (!ubi_dbg_chk_fastmap(ubi) || !seen) + return 0; + + for (pnum = 0; pnum < ubi->peb_count; pnum++) { + if (!test_bit(pnum, seen) && ubi->lookuptbl[pnum]) { + ubi_err(ubi, "self-check failed for PEB %d, fastmap didn't see it", pnum); + ret = -EINVAL; + } + } + + return ret; +} + +/** + * 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_sb) + + 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_io_buf *new_fm_vbuf(struct ubi_device *ubi, int vol_id) +{ + struct ubi_vid_io_buf *new; + struct ubi_vid_hdr *vh; + + new = ubi_alloc_vid_buf(ubi, GFP_KERNEL); + if (!new) + goto out; + + vh = ubi_get_vid_hdr(new); + vh->vol_type = UBI_VID_DYNAMIC; + vh->vol_id = cpu_to_be32(vol_id); + + /* UBI implementations without fastmap support have to delete the + * fastmap. + */ + vh->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 = ubi_alloc_aeb(ai, pnum, ec); + if (!aeb) + return -ENOMEM; + + 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; + + av = ubi_add_av(ai, vol_id); + if (IS_ERR(av)) + return av; + + av->data_pad = data_pad; + av->last_data_size = last_eb_bytes; + av->compat = 0; + av->vol_type = vol_type; + if (av->vol_type == UBI_STATIC_VOLUME) + av->used_ebs = used_ebs; + + dbg_bld("found volume (ID %i)", vol_id); + 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 = &av->root.rb_node, *parent = NULL; + + 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); + ubi_free_aeb(ai, 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 = ubi_alloc_aeb(ai, aeb->pnum, aeb->ec); + if (!victim) + return -ENOMEM; + + 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; + aeb->sqnum = new_aeb->sqnum; + ubi_free_aeb(ai, 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) +{ + int vol_id = be32_to_cpu(new_vh->vol_id); + struct ubi_ainf_volume *av; + + if (vol_id == UBI_FM_SB_VOLUME_ID || vol_id == UBI_FM_DATA_VOLUME_ID) { + ubi_free_aeb(ai, new_aeb); + + return 0; + } + + /* Find the volume this SEB belongs to */ + av = ubi_find_av(ai, vol_id); + if (!av) { + ubi_err(ubi, "orphaned volume in fastmap pool!"); + ubi_free_aeb(ai, new_aeb); + return UBI_BAD_FASTMAP; + } + + ubi_assert(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; + + ubi_rb_for_each_entry(node, av, &ai->volumes, rb) { + ubi_rb_for_each_entry(node2, aeb, &av->root, u.rb) { + if (aeb->pnum == pnum) { + rb_erase(&aeb->u.rb, &av->root); + av->leb_count--; + ubi_free_aeb(ai, 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 + * @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, + __be32 *pebs, int pool_size, unsigned long long *max_sqnum, + struct list_head *free) +{ + struct ubi_vid_io_buf *vb; + struct ubi_vid_hdr *vh; + struct ubi_ec_hdr *ech; + struct ubi_ainf_peb *new_aeb; + int i, pnum, err, ret = 0; + + ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); + if (!ech) + return -ENOMEM; + + vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL); + if (!vb) { + kfree(ech); + return -ENOMEM; + } + + vh = ubi_get_vid_hdr(vb); + + 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; + int image_seq; + + pnum = be32_to_cpu(pebs[i]); + + if (ubi_io_is_bad(ubi, pnum)) { + ubi_err(ubi, "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(ubi, "unable to read EC header! PEB:%i err:%i", + pnum, err); + ret = err > 0 ? UBI_BAD_FASTMAP : err; + goto out; + } else if (err == UBI_IO_BITFLIPS) + scrub = 1; + + /* + * Older UBI implementations have image_seq set to zero, so + * we shouldn't fail if image_seq == 0. + */ + image_seq = be32_to_cpu(ech->image_seq); + + if (image_seq && (image_seq != ubi->image_seq)) { + ubi_err(ubi, "bad image seq: 0x%x, expected: 0x%x", + be32_to_cpu(ech->image_seq), ubi->image_seq); + ret = UBI_BAD_FASTMAP; + goto out; + } + + err = ubi_io_read_vid_hdr(ubi, pnum, vb, 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) + scrub = 1; + + ret = add_aeb(ai, free, pnum, ec, scrub); + if (ret) + goto out; + 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; + + new_aeb = ubi_alloc_aeb(ai, pnum, be64_to_cpu(ech->ec)); + if (!new_aeb) { + ret = -ENOMEM; + goto out; + } + + 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(ubi, "fastmap pool PEBs contains damaged PEBs!"); + ret = err > 0 ? UBI_BAD_FASTMAP : err; + goto out; + } + + } + +out: + ubi_free_vid_buf(vb); + 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, free; + struct ubi_ainf_volume *av; + struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb; + struct ubi_fm_sb *fmsb; + struct ubi_fm_hdr *fmhdr; + struct ubi_fm_scan_pool *fmpl, *fmpl_wl; + 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); + ai->min_ec = UBI_MAX_ERASECOUNTER; + + 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(ubi, "bad fastmap header magic: 0x%x, expected: 0x%x", + be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC); + goto fail_bad; + } + + fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos); + fm_pos += sizeof(*fmpl); + if (fm_pos >= fm_size) + goto fail_bad; + if (be32_to_cpu(fmpl->magic) != UBI_FM_POOL_MAGIC) { + ubi_err(ubi, "bad fastmap pool magic: 0x%x, expected: 0x%x", + be32_to_cpu(fmpl->magic), UBI_FM_POOL_MAGIC); + goto fail_bad; + } + + fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos); + fm_pos += sizeof(*fmpl_wl); + if (fm_pos >= fm_size) + goto fail_bad; + if (be32_to_cpu(fmpl_wl->magic) != UBI_FM_POOL_MAGIC) { + ubi_err(ubi, "bad fastmap WL pool magic: 0x%x, expected: 0x%x", + be32_to_cpu(fmpl_wl->magic), UBI_FM_POOL_MAGIC); + goto fail_bad; + } + + pool_size = be16_to_cpu(fmpl->size); + wl_pool_size = be16_to_cpu(fmpl_wl->size); + fm->max_pool_size = be16_to_cpu(fmpl->max_size); + fm->max_wl_pool_size = be16_to_cpu(fmpl_wl->max_size); + + if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) { + ubi_err(ubi, "bad pool size: %i", pool_size); + goto fail_bad; + } + + if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) { + ubi_err(ubi, "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(ubi, "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(ubi, "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; + + ret = add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum), + be32_to_cpu(fmec->ec), 0); + if (ret) + goto fail; + } + + /* 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; + + ret = add_aeb(ai, &used, be32_to_cpu(fmec->pnum), + be32_to_cpu(fmec->ec), 0); + if (ret) + goto fail; + } + + /* 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; + + ret = add_aeb(ai, &used, be32_to_cpu(fmec->pnum), + be32_to_cpu(fmec->ec), 1); + if (ret) + goto fail; + } + + /* 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; + + ret = add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum), + be32_to_cpu(fmec->ec), 1); + if (ret) + goto fail; + } + + 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(ubi, "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 (IS_ERR(av)) { + if (PTR_ERR(av) == -EEXIST) + ubi_err(ubi, "volume (ID %i) already exists", + fmvhdr->vol_id); + + 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(ubi, "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 (pnum < 0) + continue; + + aeb = NULL; + list_for_each_entry(tmp_aeb, &used, u.list) { + if (tmp_aeb->pnum == pnum) { + aeb = tmp_aeb; + break; + } + } + + if (!aeb) { + ubi_err(ubi, "PEB %i is in EBA but not in used list", pnum); + goto fail_bad; + } + + 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); + } + } + + ret = scan_pool(ubi, ai, fmpl->pebs, pool_size, &max_sqnum, &free); + if (ret) + goto fail; + + ret = scan_pool(ubi, ai, fmpl_wl->pebs, wl_pool_size, &max_sqnum, &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_move_tail(&tmp_aeb->u.list, &ai->free); + + list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) + list_move_tail(&tmp_aeb->u.list, &ai->erase); + + ubi_assert(list_empty(&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: + list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) { + list_del(&tmp_aeb->u.list); + ubi_free_aeb(ai, tmp_aeb); + } + list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) { + list_del(&tmp_aeb->u.list); + ubi_free_aeb(ai, tmp_aeb); + } + + return ret; +} + +/** + * find_fm_anchor - find the most recent Fastmap superblock (anchor) + * @ai: UBI attach info to be filled + */ +static int find_fm_anchor(struct ubi_attach_info *ai) +{ + int ret = -1; + struct ubi_ainf_peb *aeb; + unsigned long long max_sqnum = 0; + + list_for_each_entry(aeb, &ai->fastmap, u.list) { + if (aeb->vol_id == UBI_FM_SB_VOLUME_ID && aeb->sqnum > max_sqnum) { + max_sqnum = aeb->sqnum; + ret = aeb->pnum; + } + } + + return ret; +} + +static struct ubi_ainf_peb *clone_aeb(struct ubi_attach_info *ai, + struct ubi_ainf_peb *old) +{ + struct ubi_ainf_peb *new; + + new = ubi_alloc_aeb(ai, old->pnum, old->ec); + if (!new) + return NULL; + + new->vol_id = old->vol_id; + new->sqnum = old->sqnum; + new->lnum = old->lnum; + new->scrub = old->scrub; + new->copy_flag = old->copy_flag; + + return new; +} + +/** + * ubi_scan_fastmap - scan the fastmap. + * @ubi: UBI device object + * @ai: UBI attach info to be filled + * @scan_ai: UBI attach info from the first 64 PEBs, + * used to find the most recent Fastmap data structure + * + * 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, + struct ubi_attach_info *scan_ai) +{ + struct ubi_fm_sb *fmsb, *fmsb2; + struct ubi_vid_io_buf *vb; + struct ubi_vid_hdr *vh; + struct ubi_ec_hdr *ech; + struct ubi_fastmap_layout *fm; + struct ubi_ainf_peb *aeb; + int i, used_blocks, pnum, fm_anchor, ret = 0; + size_t fm_size; + __be32 crc, tmp_crc; + unsigned long long sqnum = 0; + + fm_anchor = find_fm_anchor(scan_ai); + if (fm_anchor < 0) + return UBI_NO_FASTMAP; + + /* Copy all (possible) fastmap blocks into our new attach structure. */ + list_for_each_entry(aeb, &scan_ai->fastmap, u.list) { + struct ubi_ainf_peb *new; + + new = clone_aeb(ai, aeb); + if (!new) + return -ENOMEM; + + list_add(&new->u.list, &ai->fastmap); + } + + down_write(&ubi->fm_protect); + 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_data(ubi, fmsb, fm_anchor, 0, 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(ubi, "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(ubi, "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(ubi, "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(ubi, "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; + } + + vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL); + if (!vb) { + ret = -ENOMEM; + goto free_hdr; + } + + vh = ubi_get_vid_hdr(vb); + + for (i = 0; i < used_blocks; i++) { + int image_seq; + + pnum = be32_to_cpu(fmsb->block_loc[i]); + + if (ubi_io_is_bad(ubi, pnum)) { + ret = UBI_BAD_FASTMAP; + goto free_hdr; + } + + if (i == 0 && pnum != fm_anchor) { + ubi_err(ubi, "Fastmap anchor PEB mismatch: PEB: %i vs. %i", + pnum, fm_anchor); + 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(ubi, "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; + + image_seq = be32_to_cpu(ech->image_seq); + if (!ubi->image_seq) + ubi->image_seq = image_seq; + + /* + * Older UBI implementations have image_seq set to zero, so + * we shouldn't fail if image_seq == 0. + */ + if (image_seq && (image_seq != ubi->image_seq)) { + ubi_err(ubi, "wrong image seq:%d instead of %d", + be32_to_cpu(ech->image_seq), ubi->image_seq); + ret = UBI_BAD_FASTMAP; + goto free_hdr; + } + + ret = ubi_io_read_vid_hdr(ubi, pnum, vb, 0); + if (ret && ret != UBI_IO_BITFLIPS) { + ubi_err(ubi, "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(ubi, "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(ubi, "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_data(ubi, ubi->fm_buf + (ubi->leb_size * i), + pnum, 0, ubi->leb_size); + if (ret && ret != UBI_IO_BITFLIPS) { + ubi_err(ubi, "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(ubi, "fastmap data CRC is invalid"); + ubi_err(ubi, "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--) + kmem_cache_free(ubi_wl_entry_slab, 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(ubi, "attached by fastmap"); + ubi_msg(ubi, "fastmap pool size: %d", ubi->fm_pool.max_size); + ubi_msg(ubi, "fastmap WL pool size: %d", + ubi->fm_wl_pool.max_size); + ubi->fm_disabled = 0; + ubi->fast_attach = 1; + + ubi_free_vid_buf(vb); + kfree(ech); +out: + up_write(&ubi->fm_protect); + if (ret == UBI_BAD_FASTMAP) + ubi_err(ubi, "Attach by fastmap failed, doing a full scan!"); + return ret; + +free_hdr: + ubi_free_vid_buf(vb); + kfree(ech); +free_fm_sb: + kfree(fmsb); + kfree(fm); + goto out; +} + +int ubi_fastmap_init_checkmap(struct ubi_volume *vol, int leb_count) +{ + struct ubi_device *ubi = vol->ubi; + + if (!ubi->fast_attach) + return 0; + + vol->checkmap = kcalloc(BITS_TO_LONGS(leb_count), sizeof(unsigned long), + GFP_KERNEL); + if (!vol->checkmap) + return -ENOMEM; + + return 0; +} + +void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol) +{ + kfree(vol->checkmap); +} + +/** + * 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 *fmpl, *fmpl_wl; + struct ubi_fm_ec *fec; + struct ubi_fm_volhdr *fvh; + struct ubi_fm_eba *feba; + struct ubi_wl_entry *wl_e; + struct ubi_volume *vol; + struct ubi_vid_io_buf *avbuf, *dvbuf; + struct ubi_vid_hdr *avhdr, *dvhdr; + struct ubi_work *ubi_wrk; + struct rb_node *tmp_rb; + int ret, i, j, free_peb_count, used_peb_count, vol_count; + int scrub_peb_count, erase_peb_count; + unsigned long *seen_pebs; + + fm_raw = ubi->fm_buf; + memset(ubi->fm_buf, 0, ubi->fm_size); + + avbuf = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID); + if (!avbuf) { + ret = -ENOMEM; + goto out; + } + + dvbuf = new_fm_vbuf(ubi, UBI_FM_DATA_VOLUME_ID); + if (!dvbuf) { + ret = -ENOMEM; + goto out_free_avbuf; + } + + avhdr = ubi_get_vid_hdr(avbuf); + dvhdr = ubi_get_vid_hdr(dvbuf); + + seen_pebs = init_seen(ubi); + if (IS_ERR(seen_pebs)) { + ret = PTR_ERR(seen_pebs); + goto out_free_dvbuf; + } + + 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; + + fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos); + fm_pos += sizeof(*fmpl); + fmpl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC); + fmpl->size = cpu_to_be16(ubi->fm_pool.size); + fmpl->max_size = cpu_to_be16(ubi->fm_pool.max_size); + + for (i = 0; i < ubi->fm_pool.size; i++) { + fmpl->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]); + set_seen(ubi, ubi->fm_pool.pebs[i], seen_pebs); + } + + fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos); + fm_pos += sizeof(*fmpl_wl); + fmpl_wl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC); + fmpl_wl->size = cpu_to_be16(ubi->fm_wl_pool.size); + fmpl_wl->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size); + + for (i = 0; i < ubi->fm_wl_pool.size; i++) { + fmpl_wl->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]); + set_seen(ubi, ubi->fm_wl_pool.pebs[i], seen_pebs); + } + + ubi_for_each_free_peb(ubi, wl_e, tmp_rb) { + fec = (struct ubi_fm_ec *)(fm_raw + fm_pos); + + fec->pnum = cpu_to_be32(wl_e->pnum); + set_seen(ubi, wl_e->pnum, seen_pebs); + 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); + + ubi_for_each_used_peb(ubi, wl_e, tmp_rb) { + fec = (struct ubi_fm_ec *)(fm_raw + fm_pos); + + fec->pnum = cpu_to_be32(wl_e->pnum); + set_seen(ubi, wl_e->pnum, seen_pebs); + fec->ec = cpu_to_be32(wl_e->ec); + + used_peb_count++; + fm_pos += sizeof(*fec); + ubi_assert(fm_pos <= ubi->fm_size); + } + + ubi_for_each_protected_peb(ubi, i, wl_e) { + fec = (struct ubi_fm_ec *)(fm_raw + fm_pos); + + fec->pnum = cpu_to_be32(wl_e->pnum); + set_seen(ubi, wl_e->pnum, seen_pebs); + 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); + + ubi_for_each_scrub_peb(ubi, wl_e, tmp_rb) { + fec = (struct ubi_fm_ec *)(fm_raw + fm_pos); + + fec->pnum = cpu_to_be32(wl_e->pnum); + set_seen(ubi, wl_e->pnum, seen_pebs); + 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); + set_seen(ubi, wl_e->pnum, seen_pebs); + 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++) { + struct ubi_eba_leb_desc ldesc; + + ubi_eba_get_ldesc(vol, j, &ldesc); + feba->pnum[j] = cpu_to_be32(ldesc.pnum); + } + + 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, avbuf); + if (ret) { + ubi_err(ubi, "unable to write vid_hdr to fastmap SB!"); + goto out_free_seen; + } + + for (i = 0; i < new_fm->used_blocks; i++) { + fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum); + set_seen(ubi, new_fm->e[i]->pnum, seen_pebs); + 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, dvbuf); + if (ret) { + ubi_err(ubi, "unable to write vid_hdr to PEB %i!", + new_fm->e[i]->pnum); + goto out_free_seen; + } + } + + for (i = 0; i < new_fm->used_blocks; i++) { + ret = ubi_io_write_data(ubi, fm_raw + (i * ubi->leb_size), + new_fm->e[i]->pnum, 0, ubi->leb_size); + if (ret) { + ubi_err(ubi, "unable to write fastmap to PEB %i!", + new_fm->e[i]->pnum); + goto out_free_seen; + } + } + + ubi_assert(new_fm); + ubi->fm = new_fm; + + ret = self_check_seen(ubi, seen_pebs); + dbg_bld("fastmap written!"); + +out_free_seen: + free_seen(seen_pebs); +out_free_dvbuf: + ubi_free_vid_buf(dvbuf); +out_free_avbuf: + ubi_free_vid_buf(avbuf); + +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 + * + * This function ensures that upon next UBI attach a full scan + * is issued. We need this if UBI is about to write a new fastmap + * but is unable to do so. In this case we have two options: + * a) Make sure that the current fastmap will not be usued upon + * attach time and contine or b) fall back to RO mode to have the + * current fastmap in a valid state. + * Returns 0 on success, < 0 indicates an internal error. + */ +static int invalidate_fastmap(struct ubi_device *ubi) +{ + int ret; + struct ubi_fastmap_layout *fm; + struct ubi_wl_entry *e; + struct ubi_vid_io_buf *vb = NULL; + struct ubi_vid_hdr *vh; + + if (!ubi->fm) + return 0; + + ubi->fm = NULL; + + ret = -ENOMEM; + fm = kzalloc(sizeof(*fm), GFP_KERNEL); + if (!fm) + goto out; + + vb = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID); + if (!vb) + goto out_free_fm; + + vh = ubi_get_vid_hdr(vb); + + ret = -ENOSPC; + e = ubi_wl_get_fm_peb(ubi, 1); + if (!e) + goto out_free_fm; + + /* + * Create fake fastmap such that UBI will fall back + * to scanning mode. + */ + vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); + ret = ubi_io_write_vid_hdr(ubi, e->pnum, vb); + if (ret < 0) { + ubi_wl_put_fm_peb(ubi, e, 0, 0); + goto out_free_fm; + } + + fm->used_blocks = 1; + fm->e[0] = e; + + ubi->fm = fm; + +out: + ubi_free_vid_buf(vb); + return ret; + +out_free_fm: + kfree(fm); + goto out; +} + +/** + * return_fm_pebs - returns all PEBs used by a fastmap back to the + * WL sub-system. + * @ubi: UBI device object + * @fm: fastmap layout object + */ +static void return_fm_pebs(struct ubi_device *ubi, + struct ubi_fastmap_layout *fm) +{ + int i; + + if (!fm) + return; + + for (i = 0; i < fm->used_blocks; i++) { + if (fm->e[i]) { + ubi_wl_put_fm_peb(ubi, fm->e[i], i, + fm->to_be_tortured[i]); + fm->e[i] = NULL; + } + } +} + +/** + * 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, j; + struct ubi_fastmap_layout *new_fm, *old_fm; + struct ubi_wl_entry *tmp_e; + + down_write(&ubi->fm_protect); + down_write(&ubi->work_sem); + down_write(&ubi->fm_eba_sem); + + ubi_refill_pools(ubi); + + if (ubi->ro_mode || ubi->fm_disabled) { + up_write(&ubi->fm_eba_sem); + up_write(&ubi->work_sem); + up_write(&ubi->fm_protect); + return 0; + } + + new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL); + if (!new_fm) { + up_write(&ubi->fm_eba_sem); + up_write(&ubi->work_sem); + up_write(&ubi->fm_protect); + return -ENOMEM; + } + + new_fm->used_blocks = ubi->fm_size / ubi->leb_size; + old_fm = ubi->fm; + ubi->fm = NULL; + + if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) { + ubi_err(ubi, "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) { + if (old_fm && old_fm->e[i]) { + ret = erase_block(ubi, old_fm->e[i]->pnum); + if (ret < 0) { + ubi_err(ubi, "could not erase old fastmap PEB"); + + for (j = 1; j < i; j++) { + ubi_wl_put_fm_peb(ubi, new_fm->e[j], + j, 0); + new_fm->e[j] = NULL; + } + goto err; + } + new_fm->e[i] = old_fm->e[i]; + old_fm->e[i] = NULL; + } else { + ubi_err(ubi, "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); + new_fm->e[j] = NULL; + } + + ret = -ENOSPC; + goto err; + } + } else { + new_fm->e[i] = tmp_e; + + if (old_fm && old_fm->e[i]) { + ubi_wl_put_fm_peb(ubi, old_fm->e[i], i, + old_fm->to_be_tortured[i]); + old_fm->e[i] = NULL; + } + } + } + + /* Old fastmap is larger than the new one */ + if (old_fm && new_fm->used_blocks < old_fm->used_blocks) { + for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) { + ubi_wl_put_fm_peb(ubi, old_fm->e[i], i, + old_fm->to_be_tortured[i]); + old_fm->e[i] = NULL; + } + } + + spin_lock(&ubi->wl_lock); + tmp_e = ubi->fm_anchor; + ubi->fm_anchor = NULL; + 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) { + ubi_err(ubi, "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); + new_fm->e[i] = NULL; + } + goto err; + } + new_fm->e[0] = old_fm->e[0]; + new_fm->e[0]->ec = ret; + old_fm->e[0] = NULL; + } 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] = tmp_e; + old_fm->e[0] = NULL; + } + } else { + if (!tmp_e) { + ubi_err(ubi, "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); + new_fm->e[i] = NULL; + } + + ret = -ENOSPC; + goto err; + } + new_fm->e[0] = tmp_e; + } + + ret = ubi_write_fastmap(ubi, new_fm); + + if (ret) + goto err; + +out_unlock: + up_write(&ubi->fm_eba_sem); + up_write(&ubi->work_sem); + up_write(&ubi->fm_protect); + kfree(old_fm); + + ubi_ensure_anchor_pebs(ubi); + + return ret; + +err: + ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret); + + ret = invalidate_fastmap(ubi); + if (ret < 0) { + ubi_err(ubi, "Unable to invalidate current fastmap!"); + ubi_ro_mode(ubi); + } else { + return_fm_pebs(ubi, old_fm); + return_fm_pebs(ubi, new_fm); + ret = 0; + } + + kfree(new_fm); + goto out_unlock; +} |