| /* |
| * Copyright (c) International Business Machines Corp., 2006 |
| * |
| * 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; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * 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. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| * |
| * Author: Artem Bityutskiy (Битюцкий Артём) |
| */ |
| |
| /* |
| * UBI scanning unit. |
| * |
| * This unit is responsible for scanning the flash media, checking UBI |
| * headers and providing complete information about the UBI flash image. |
| * |
| * The scanning information is represented by a &struct ubi_scan_info' object. |
| * Information about found volumes is represented by &struct ubi_scan_volume |
| * objects which are kept in volume RB-tree with root at the @volumes field. |
| * The RB-tree is indexed by the volume ID. |
| * |
| * Found logical eraseblocks are represented by &struct ubi_scan_leb objects. |
| * These objects are kept in per-volume RB-trees with the root at the |
| * corresponding &struct ubi_scan_volume object. To put it differently, we keep |
| * an RB-tree of per-volume objects and each of these objects is the root of |
| * RB-tree of per-eraseblock objects. |
| * |
| * Corrupted physical eraseblocks are put to the @corr list, free physical |
| * eraseblocks are put to the @free list and the physical eraseblock to be |
| * erased are put to the @erase list. |
| */ |
| |
| #include <linux/err.h> |
| #include <linux/crc32.h> |
| #include "ubi.h" |
| |
| #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID |
| static int paranoid_check_si(const struct ubi_device *ubi, |
| struct ubi_scan_info *si); |
| #else |
| #define paranoid_check_si(ubi, si) 0 |
| #endif |
| |
| /* Temporary variables used during scanning */ |
| static struct ubi_ec_hdr *ech; |
| static struct ubi_vid_hdr *vidh; |
| |
| /* |
| * add_to_list - add physical eraseblock to a list. |
| * @si: scanning information |
| * @pnum: physical eraseblock number to add |
| * @ec: erase counter of the physical eraseblock |
| * @list: the list to add to |
| * |
| * This function adds physical eraseblock @pnum to free, erase, corrupted or |
| * alien lists. Returns zero in case of success and a negative error code in |
| * case of failure. |
| */ |
| static int add_to_list(struct ubi_scan_info *si, int pnum, int ec, |
| struct list_head *list) |
| { |
| struct ubi_scan_leb *seb; |
| |
| if (list == &si->free) |
| dbg_bld("add to free: PEB %d, EC %d", pnum, ec); |
| else if (list == &si->erase) |
| dbg_bld("add to erase: PEB %d, EC %d", pnum, ec); |
| else if (list == &si->corr) |
| dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec); |
| else if (list == &si->alien) |
| dbg_bld("add to alien: PEB %d, EC %d", pnum, ec); |
| else |
| BUG(); |
| |
| seb = kmalloc(sizeof(struct ubi_scan_leb), GFP_KERNEL); |
| if (!seb) |
| return -ENOMEM; |
| |
| seb->pnum = pnum; |
| seb->ec = ec; |
| list_add_tail(&seb->u.list, list); |
| return 0; |
| } |
| |
| /** |
| * commit_to_mean_value - commit intermediate results to the final mean erase |
| * counter value. |
| * @si: scanning information |
| * |
| * This is a helper function which calculates partial mean erase counter mean |
| * value and adds it to the resulting mean value. As we can work only in |
| * integer arithmetic and we want to calculate the mean value of erase counter |
| * accurately, we first sum erase counter values in @si->ec_sum variable and |
| * count these components in @si->ec_count. If this temporary @si->ec_sum is |
| * going to overflow, we calculate the partial mean value |
| * (@si->ec_sum/@si->ec_count) and add it to @si->mean_ec. |
| */ |
| static void commit_to_mean_value(struct ubi_scan_info *si) |
| { |
| si->ec_sum /= si->ec_count; |
| if (si->ec_sum % si->ec_count >= si->ec_count / 2) |
| si->mean_ec += 1; |
| si->mean_ec += si->ec_sum; |
| } |
| |
| /** |
| * validate_vid_hdr - check that volume identifier header is correct and |
| * consistent. |
| * @vid_hdr: the volume identifier header to check |
| * @sv: information about the volume this logical eraseblock belongs to |
| * @pnum: physical eraseblock number the VID header came from |
| * |
| * This function checks that data stored in @vid_hdr is consistent. Returns |
| * non-zero if an inconsistency was found and zero if not. |
| * |
| * Note, UBI does sanity check of everything it reads from the flash media. |
| * Most of the checks are done in the I/O unit. Here we check that the |
| * information in the VID header is consistent to the information in other VID |
| * headers of the same volume. |
| */ |
| static int validate_vid_hdr(const struct ubi_vid_hdr *vid_hdr, |
| const struct ubi_scan_volume *sv, int pnum) |
| { |
| int vol_type = vid_hdr->vol_type; |
| int vol_id = ubi32_to_cpu(vid_hdr->vol_id); |
| int used_ebs = ubi32_to_cpu(vid_hdr->used_ebs); |
| int data_pad = ubi32_to_cpu(vid_hdr->data_pad); |
| |
| if (sv->leb_count != 0) { |
| int sv_vol_type; |
| |
| /* |
| * This is not the first logical eraseblock belonging to this |
| * volume. Ensure that the data in its VID header is consistent |
| * to the data in previous logical eraseblock headers. |
| */ |
| |
| if (vol_id != sv->vol_id) { |
| dbg_err("inconsistent vol_id"); |
| goto bad; |
| } |
| |
| if (sv->vol_type == UBI_STATIC_VOLUME) |
| sv_vol_type = UBI_VID_STATIC; |
| else |
| sv_vol_type = UBI_VID_DYNAMIC; |
| |
| if (vol_type != sv_vol_type) { |
| dbg_err("inconsistent vol_type"); |
| goto bad; |
| } |
| |
| if (used_ebs != sv->used_ebs) { |
| dbg_err("inconsistent used_ebs"); |
| goto bad; |
| } |
| |
| if (data_pad != sv->data_pad) { |
| dbg_err("inconsistent data_pad"); |
| goto bad; |
| } |
| } |
| |
| return 0; |
| |
| bad: |
| ubi_err("inconsistent VID header at PEB %d", pnum); |
| ubi_dbg_dump_vid_hdr(vid_hdr); |
| ubi_dbg_dump_sv(sv); |
| return -EINVAL; |
| } |
| |
| /** |
| * add_volume - add volume to the scanning information. |
| * @si: scanning information |
| * @vol_id: ID of the volume to add |
| * @pnum: physical eraseblock number |
| * @vid_hdr: volume identifier header |
| * |
| * If the volume corresponding to the @vid_hdr logical eraseblock is already |
| * present in the scanning information, this function does nothing. Otherwise |
| * it adds corresponding volume to the scanning information. Returns a pointer |
| * to the scanning volume object in case of success and a negative error code |
| * in case of failure. |
| */ |
| static struct ubi_scan_volume *add_volume(struct ubi_scan_info *si, int vol_id, |
| int pnum, |
| const struct ubi_vid_hdr *vid_hdr) |
| { |
| struct ubi_scan_volume *sv; |
| struct rb_node **p = &si->volumes.rb_node, *parent = NULL; |
| |
| ubi_assert(vol_id == ubi32_to_cpu(vid_hdr->vol_id)); |
| |
| /* Walk the volume RB-tree to look if this volume is already present */ |
| while (*p) { |
| parent = *p; |
| sv = rb_entry(parent, struct ubi_scan_volume, rb); |
| |
| if (vol_id == sv->vol_id) |
| return sv; |
| |
| if (vol_id > sv->vol_id) |
| p = &(*p)->rb_left; |
| else |
| p = &(*p)->rb_right; |
| } |
| |
| /* The volume is absent - add it */ |
| sv = kmalloc(sizeof(struct ubi_scan_volume), GFP_KERNEL); |
| if (!sv) |
| return ERR_PTR(-ENOMEM); |
| |
| sv->highest_lnum = sv->leb_count = 0; |
| si->max_sqnum = 0; |
| sv->vol_id = vol_id; |
| sv->root = RB_ROOT; |
| sv->used_ebs = ubi32_to_cpu(vid_hdr->used_ebs); |
| sv->data_pad = ubi32_to_cpu(vid_hdr->data_pad); |
| sv->compat = vid_hdr->compat; |
| sv->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME |
| : UBI_STATIC_VOLUME; |
| if (vol_id > si->highest_vol_id) |
| si->highest_vol_id = vol_id; |
| |
| rb_link_node(&sv->rb, parent, p); |
| rb_insert_color(&sv->rb, &si->volumes); |
| si->vols_found += 1; |
| dbg_bld("added volume %d", vol_id); |
| return sv; |
| } |
| |
| /** |
| * compare_lebs - find out which logical eraseblock is newer. |
| * @ubi: UBI device description object |
| * @seb: first logical eraseblock to compare |
| * @pnum: physical eraseblock number of the second logical eraseblock to |
| * compare |
| * @vid_hdr: volume identifier header of the second logical eraseblock |
| * |
| * This function compares 2 copies of a LEB and informs which one is newer. In |
| * case of success this function returns a positive value, in case of failure, a |
| * negative error code is returned. The success return codes use the following |
| * bits: |
| * o bit 0 is cleared: the first PEB (described by @seb) is newer then the |
| * second PEB (described by @pnum and @vid_hdr); |
| * o bit 0 is set: the second PEB is newer; |
| * o bit 1 is cleared: no bit-flips were detected in the newer LEB; |
| * o bit 1 is set: bit-flips were detected in the newer LEB; |
| * o bit 2 is cleared: the older LEB is not corrupted; |
| * o bit 2 is set: the older LEB is corrupted. |
| */ |
| static int compare_lebs(const struct ubi_device *ubi, |
| const struct ubi_scan_leb *seb, int pnum, |
| const struct ubi_vid_hdr *vid_hdr) |
| { |
| void *buf; |
| int len, err, second_is_newer, bitflips = 0, corrupted = 0; |
| uint32_t data_crc, crc; |
| struct ubi_vid_hdr *vidh = NULL; |
| unsigned long long sqnum2 = ubi64_to_cpu(vid_hdr->sqnum); |
| |
| if (seb->sqnum == 0 && sqnum2 == 0) { |
| long long abs, v1 = seb->leb_ver, v2 = ubi32_to_cpu(vid_hdr->leb_ver); |
| |
| /* |
| * UBI constantly increases the logical eraseblock version |
| * number and it can overflow. Thus, we have to bear in mind |
| * that versions that are close to %0xFFFFFFFF are less then |
| * versions that are close to %0. |
| * |
| * The UBI WL unit guarantees that the number of pending tasks |
| * is not greater then %0x7FFFFFFF. So, if the difference |
| * between any two versions is greater or equivalent to |
| * %0x7FFFFFFF, there was an overflow and the logical |
| * eraseblock with lower version is actually newer then the one |
| * with higher version. |
| * |
| * FIXME: but this is anyway obsolete and will be removed at |
| * some point. |
| */ |
| |
| dbg_bld("using old crappy leb_ver stuff"); |
| |
| abs = v1 - v2; |
| if (abs < 0) |
| abs = -abs; |
| |
| if (abs < 0x7FFFFFFF) |
| /* Non-overflow situation */ |
| second_is_newer = (v2 > v1); |
| else |
| second_is_newer = (v2 < v1); |
| } else |
| /* Obviously the LEB with lower sequence counter is older */ |
| second_is_newer = sqnum2 > seb->sqnum; |
| |
| /* |
| * Now we know which copy is newer. If the copy flag of the PEB with |
| * newer version is not set, then we just return, otherwise we have to |
| * check data CRC. For the second PEB we already have the VID header, |
| * for the first one - we'll need to re-read it from flash. |
| * |
| * FIXME: this may be optimized so that we wouldn't read twice. |
| */ |
| |
| if (second_is_newer) { |
| if (!vid_hdr->copy_flag) { |
| /* It is not a copy, so it is newer */ |
| dbg_bld("second PEB %d is newer, copy_flag is unset", |
| pnum); |
| return 1; |
| } |
| } else { |
| pnum = seb->pnum; |
| |
| vidh = ubi_zalloc_vid_hdr(ubi); |
| if (!vidh) |
| return -ENOMEM; |
| |
| err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0); |
| if (err) { |
| if (err == UBI_IO_BITFLIPS) |
| bitflips = 1; |
| else { |
| dbg_err("VID of PEB %d header is bad, but it " |
| "was OK earlier", pnum); |
| if (err > 0) |
| err = -EIO; |
| |
| goto out_free_vidh; |
| } |
| } |
| |
| if (!vidh->copy_flag) { |
| /* It is not a copy, so it is newer */ |
| dbg_bld("first PEB %d is newer, copy_flag is unset", |
| pnum); |
| err = bitflips << 1; |
| goto out_free_vidh; |
| } |
| |
| vid_hdr = vidh; |
| } |
| |
| /* Read the data of the copy and check the CRC */ |
| |
| len = ubi32_to_cpu(vid_hdr->data_size); |
| buf = kmalloc(len, GFP_KERNEL); |
| if (!buf) { |
| err = -ENOMEM; |
| goto out_free_vidh; |
| } |
| |
| err = ubi_io_read_data(ubi, buf, pnum, 0, len); |
| if (err && err != UBI_IO_BITFLIPS) |
| goto out_free_buf; |
| |
| data_crc = ubi32_to_cpu(vid_hdr->data_crc); |
| crc = crc32(UBI_CRC32_INIT, buf, len); |
| if (crc != data_crc) { |
| dbg_bld("PEB %d CRC error: calculated %#08x, must be %#08x", |
| pnum, crc, data_crc); |
| corrupted = 1; |
| bitflips = 0; |
| second_is_newer = !second_is_newer; |
| } else { |
| dbg_bld("PEB %d CRC is OK", pnum); |
| bitflips = !!err; |
| } |
| |
| kfree(buf); |
| ubi_free_vid_hdr(ubi, vidh); |
| |
| if (second_is_newer) |
| dbg_bld("second PEB %d is newer, copy_flag is set", pnum); |
| else |
| dbg_bld("first PEB %d is newer, copy_flag is set", pnum); |
| |
| return second_is_newer | (bitflips << 1) | (corrupted << 2); |
| |
| out_free_buf: |
| kfree(buf); |
| out_free_vidh: |
| ubi_free_vid_hdr(ubi, vidh); |
| ubi_assert(err < 0); |
| return err; |
| } |
| |
| /** |
| * ubi_scan_add_used - add information about a physical eraseblock to the |
| * scanning information. |
| * @ubi: UBI device description object |
| * @si: scanning information |
| * @pnum: the physical eraseblock number |
| * @ec: erase counter |
| * @vid_hdr: the volume identifier header |
| * @bitflips: if bit-flips were detected when this physical eraseblock was read |
| * |
| * This function returns zero in case of success and a negative error code in |
| * case of failure. |
| */ |
| int ubi_scan_add_used(const struct ubi_device *ubi, struct ubi_scan_info *si, |
| int pnum, int ec, const struct ubi_vid_hdr *vid_hdr, |
| int bitflips) |
| { |
| int err, vol_id, lnum; |
| uint32_t leb_ver; |
| unsigned long long sqnum; |
| struct ubi_scan_volume *sv; |
| struct ubi_scan_leb *seb; |
| struct rb_node **p, *parent = NULL; |
| |
| vol_id = ubi32_to_cpu(vid_hdr->vol_id); |
| lnum = ubi32_to_cpu(vid_hdr->lnum); |
| sqnum = ubi64_to_cpu(vid_hdr->sqnum); |
| leb_ver = ubi32_to_cpu(vid_hdr->leb_ver); |
| |
| dbg_bld("PEB %d, LEB %d:%d, EC %d, sqnum %llu, ver %u, bitflips %d", |
| pnum, vol_id, lnum, ec, sqnum, leb_ver, bitflips); |
| |
| sv = add_volume(si, vol_id, pnum, vid_hdr); |
| if (IS_ERR(sv) < 0) |
| return PTR_ERR(sv); |
| |
| /* |
| * Walk the RB-tree of logical eraseblocks of volume @vol_id to look |
| * if this is the first instance of this logical eraseblock or not. |
| */ |
| p = &sv->root.rb_node; |
| while (*p) { |
| int cmp_res; |
| |
| parent = *p; |
| seb = rb_entry(parent, struct ubi_scan_leb, u.rb); |
| if (lnum != seb->lnum) { |
| if (lnum < seb->lnum) |
| p = &(*p)->rb_left; |
| else |
| p = &(*p)->rb_right; |
| continue; |
| } |
| |
| /* |
| * There is already a physical eraseblock describing the same |
| * logical eraseblock present. |
| */ |
| |
| dbg_bld("this LEB already exists: PEB %d, sqnum %llu, " |
| "LEB ver %u, EC %d", seb->pnum, seb->sqnum, |
| seb->leb_ver, seb->ec); |
| |
| /* |
| * Make sure that the logical eraseblocks have different |
| * versions. Otherwise the image is bad. |
| */ |
| if (seb->leb_ver == leb_ver && leb_ver != 0) { |
| ubi_err("two LEBs with same version %u", leb_ver); |
| ubi_dbg_dump_seb(seb, 0); |
| ubi_dbg_dump_vid_hdr(vid_hdr); |
| return -EINVAL; |
| } |
| |
| /* |
| * Make sure that the logical eraseblocks have different |
| * sequence numbers. Otherwise the image is bad. |
| * |
| * FIXME: remove 'sqnum != 0' check when leb_ver is removed. |
| */ |
| if (seb->sqnum == sqnum && sqnum != 0) { |
| ubi_err("two LEBs with same sequence number %llu", |
| sqnum); |
| ubi_dbg_dump_seb(seb, 0); |
| ubi_dbg_dump_vid_hdr(vid_hdr); |
| return -EINVAL; |
| } |
| |
| /* |
| * Now we have to drop the older one and preserve the newer |
| * one. |
| */ |
| cmp_res = compare_lebs(ubi, seb, pnum, vid_hdr); |
| if (cmp_res < 0) |
| return cmp_res; |
| |
| if (cmp_res & 1) { |
| /* |
| * This logical eraseblock is newer then the one |
| * found earlier. |
| */ |
| err = validate_vid_hdr(vid_hdr, sv, pnum); |
| if (err) |
| return err; |
| |
| if (cmp_res & 4) |
| err = add_to_list(si, seb->pnum, seb->ec, |
| &si->corr); |
| else |
| err = add_to_list(si, seb->pnum, seb->ec, |
| &si->erase); |
| if (err) |
| return err; |
| |
| seb->ec = ec; |
| seb->pnum = pnum; |
| seb->scrub = ((cmp_res & 2) || bitflips); |
| seb->sqnum = sqnum; |
| seb->leb_ver = leb_ver; |
| |
| if (sv->highest_lnum == lnum) |
| sv->last_data_size = |
| ubi32_to_cpu(vid_hdr->data_size); |
| |
| return 0; |
| } else { |
| /* |
| * This logical eraseblock is older then the one found |
| * previously. |
| */ |
| if (cmp_res & 4) |
| return add_to_list(si, pnum, ec, &si->corr); |
| else |
| return add_to_list(si, pnum, ec, &si->erase); |
| } |
| } |
| |
| /* |
| * We've met this logical eraseblock for the first time, add it to the |
| * scanning information. |
| */ |
| |
| err = validate_vid_hdr(vid_hdr, sv, pnum); |
| if (err) |
| return err; |
| |
| seb = kmalloc(sizeof(struct ubi_scan_leb), GFP_KERNEL); |
| if (!seb) |
| return -ENOMEM; |
| |
| seb->ec = ec; |
| seb->pnum = pnum; |
| seb->lnum = lnum; |
| seb->sqnum = sqnum; |
| seb->scrub = bitflips; |
| seb->leb_ver = leb_ver; |
| |
| if (sv->highest_lnum <= lnum) { |
| sv->highest_lnum = lnum; |
| sv->last_data_size = ubi32_to_cpu(vid_hdr->data_size); |
| } |
| |
| if (si->max_sqnum < sqnum) |
| si->max_sqnum = sqnum; |
| |
| sv->leb_count += 1; |
| rb_link_node(&seb->u.rb, parent, p); |
| rb_insert_color(&seb->u.rb, &sv->root); |
| return 0; |
| } |
| |
| /** |
| * ubi_scan_find_sv - find information about a particular volume in the |
| * scanning information. |
| * @si: scanning information |
| * @vol_id: the requested volume ID |
| * |
| * This function returns a pointer to the volume description or %NULL if there |
| * are no data about this volume in the scanning information. |
| */ |
| struct ubi_scan_volume *ubi_scan_find_sv(const struct ubi_scan_info *si, |
| int vol_id) |
| { |
| struct ubi_scan_volume *sv; |
| struct rb_node *p = si->volumes.rb_node; |
| |
| while (p) { |
| sv = rb_entry(p, struct ubi_scan_volume, rb); |
| |
| if (vol_id == sv->vol_id) |
| return sv; |
| |
| if (vol_id > sv->vol_id) |
| p = p->rb_left; |
| else |
| p = p->rb_right; |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * ubi_scan_find_seb - find information about a particular logical |
| * eraseblock in the volume scanning information. |
| * @sv: a pointer to the volume scanning information |
| * @lnum: the requested logical eraseblock |
| * |
| * This function returns a pointer to the scanning logical eraseblock or %NULL |
| * if there are no data about it in the scanning volume information. |
| */ |
| struct ubi_scan_leb *ubi_scan_find_seb(const struct ubi_scan_volume *sv, |
| int lnum) |
| { |
| struct ubi_scan_leb *seb; |
| struct rb_node *p = sv->root.rb_node; |
| |
| while (p) { |
| seb = rb_entry(p, struct ubi_scan_leb, u.rb); |
| |
| if (lnum == seb->lnum) |
| return seb; |
| |
| if (lnum > seb->lnum) |
| p = p->rb_left; |
| else |
| p = p->rb_right; |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * ubi_scan_rm_volume - delete scanning information about a volume. |
| * @si: scanning information |
| * @sv: the volume scanning information to delete |
| */ |
| void ubi_scan_rm_volume(struct ubi_scan_info *si, struct ubi_scan_volume *sv) |
| { |
| struct rb_node *rb; |
| struct ubi_scan_leb *seb; |
| |
| dbg_bld("remove scanning information about volume %d", sv->vol_id); |
| |
| while ((rb = rb_first(&sv->root))) { |
| seb = rb_entry(rb, struct ubi_scan_leb, u.rb); |
| rb_erase(&seb->u.rb, &sv->root); |
| list_add_tail(&seb->u.list, &si->erase); |
| } |
| |
| rb_erase(&sv->rb, &si->volumes); |
| kfree(sv); |
| si->vols_found -= 1; |
| } |
| |
| /** |
| * ubi_scan_erase_peb - erase a physical eraseblock. |
| * @ubi: UBI device description object |
| * @si: scanning information |
| * @pnum: physical eraseblock number to erase; |
| * @ec: erase counter value to write (%UBI_SCAN_UNKNOWN_EC if it is unknown) |
| * |
| * This function erases physical eraseblock 'pnum', and writes the erase |
| * counter header to it. This function should only be used on UBI device |
| * initialization stages, when the EBA unit had not been yet initialized. This |
| * function returns zero in case of success and a negative error code in case |
| * of failure. |
| */ |
| int ubi_scan_erase_peb(const struct ubi_device *ubi, |
| const struct ubi_scan_info *si, int pnum, int ec) |
| { |
| int err; |
| struct ubi_ec_hdr *ec_hdr; |
| |
| ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| if (!ec_hdr) |
| return -ENOMEM; |
| |
| if ((long long)ec >= UBI_MAX_ERASECOUNTER) { |
| /* |
| * Erase counter overflow. Upgrade UBI and use 64-bit |
| * erase counters internally. |
| */ |
| ubi_err("erase counter overflow at PEB %d, EC %d", pnum, ec); |
| return -EINVAL; |
| } |
| |
| ec_hdr->ec = cpu_to_ubi64(ec); |
| |
| err = ubi_io_sync_erase(ubi, pnum, 0); |
| if (err < 0) |
| goto out_free; |
| |
| err = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr); |
| |
| out_free: |
| kfree(ec_hdr); |
| return err; |
| } |
| |
| /** |
| * ubi_scan_get_free_peb - get a free physical eraseblock. |
| * @ubi: UBI device description object |
| * @si: scanning information |
| * |
| * This function returns a free physical eraseblock. It is supposed to be |
| * called on the UBI initialization stages when the wear-leveling unit is not |
| * initialized yet. This function picks a physical eraseblocks from one of the |
| * lists, writes the EC header if it is needed, and removes it from the list. |
| * |
| * This function returns scanning physical eraseblock information in case of |
| * success and an error code in case of failure. |
| */ |
| struct ubi_scan_leb *ubi_scan_get_free_peb(const struct ubi_device *ubi, |
| struct ubi_scan_info *si) |
| { |
| int err = 0, i; |
| struct ubi_scan_leb *seb; |
| |
| if (!list_empty(&si->free)) { |
| seb = list_entry(si->free.next, struct ubi_scan_leb, u.list); |
| list_del(&seb->u.list); |
| dbg_bld("return free PEB %d, EC %d", seb->pnum, seb->ec); |
| return seb; |
| } |
| |
| for (i = 0; i < 2; i++) { |
| struct list_head *head; |
| struct ubi_scan_leb *tmp_seb; |
| |
| if (i == 0) |
| head = &si->erase; |
| else |
| head = &si->corr; |
| |
| /* |
| * We try to erase the first physical eraseblock from the @head |
| * list and pick it if we succeed, or try to erase the |
| * next one if not. And so forth. We don't want to take care |
| * about bad eraseblocks here - they'll be handled later. |
| */ |
| list_for_each_entry_safe(seb, tmp_seb, head, u.list) { |
| if (seb->ec == UBI_SCAN_UNKNOWN_EC) |
| seb->ec = si->mean_ec; |
| |
| err = ubi_scan_erase_peb(ubi, si, seb->pnum, seb->ec+1); |
| if (err) |
| continue; |
| |
| seb->ec += 1; |
| list_del(&seb->u.list); |
| dbg_bld("return PEB %d, EC %d", seb->pnum, seb->ec); |
| return seb; |
| } |
| } |
| |
| ubi_err("no eraseblocks found"); |
| return ERR_PTR(-ENOSPC); |
| } |
| |
| /** |
| * process_eb - read UBI headers, check them and add corresponding data |
| * to the scanning information. |
| * @ubi: UBI device description object |
| * @si: scanning information |
| * @pnum: the physical eraseblock number |
| * |
| * This function returns a zero if the physical eraseblock was successfully |
| * handled and a negative error code in case of failure. |
| */ |
| static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si, int pnum) |
| { |
| long long ec; |
| int err, bitflips = 0, vol_id, ec_corr = 0; |
| |
| dbg_bld("scan PEB %d", pnum); |
| |
| /* Skip bad physical eraseblocks */ |
| err = ubi_io_is_bad(ubi, pnum); |
| if (err < 0) |
| return err; |
| else if (err) { |
| /* |
| * FIXME: this is actually duty of the I/O unit to initialize |
| * this, but MTD does not provide enough information. |
| */ |
| si->bad_peb_count += 1; |
| return 0; |
| } |
| |
| err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0); |
| if (err < 0) |
| return err; |
| else if (err == UBI_IO_BITFLIPS) |
| bitflips = 1; |
| else if (err == UBI_IO_PEB_EMPTY) |
| return add_to_list(si, pnum, UBI_SCAN_UNKNOWN_EC, &si->erase); |
| else if (err == UBI_IO_BAD_EC_HDR) { |
| /* |
| * We have to also look at the VID header, possibly it is not |
| * corrupted. Set %bitflips flag in order to make this PEB be |
| * moved and EC be re-created. |
| */ |
| ec_corr = 1; |
| ec = UBI_SCAN_UNKNOWN_EC; |
| bitflips = 1; |
| } |
| |
| si->is_empty = 0; |
| |
| if (!ec_corr) { |
| /* Make sure UBI version is OK */ |
| if (ech->version != UBI_VERSION) { |
| ubi_err("this UBI version is %d, image version is %d", |
| UBI_VERSION, (int)ech->version); |
| return -EINVAL; |
| } |
| |
| ec = ubi64_to_cpu(ech->ec); |
| if (ec > UBI_MAX_ERASECOUNTER) { |
| /* |
| * Erase counter overflow. The EC headers have 64 bits |
| * reserved, but we anyway make use of only 31 bit |
| * values, as this seems to be enough for any existing |
| * flash. Upgrade UBI and use 64-bit erase counters |
| * internally. |
| */ |
| ubi_err("erase counter overflow, max is %d", |
| UBI_MAX_ERASECOUNTER); |
| ubi_dbg_dump_ec_hdr(ech); |
| return -EINVAL; |
| } |
| } |
| |
| /* OK, we've done with the EC header, let's look at the VID header */ |
| |
| err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0); |
| if (err < 0) |
| return err; |
| else if (err == UBI_IO_BITFLIPS) |
| bitflips = 1; |
| else if (err == UBI_IO_BAD_VID_HDR || |
| (err == UBI_IO_PEB_FREE && ec_corr)) { |
| /* VID header is corrupted */ |
| err = add_to_list(si, pnum, ec, &si->corr); |
| if (err) |
| return err; |
| goto adjust_mean_ec; |
| } else if (err == UBI_IO_PEB_FREE) { |
| /* No VID header - the physical eraseblock is free */ |
| err = add_to_list(si, pnum, ec, &si->free); |
| if (err) |
| return err; |
| goto adjust_mean_ec; |
| } |
| |
| vol_id = ubi32_to_cpu(vidh->vol_id); |
| if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOL_ID) { |
| int lnum = ubi32_to_cpu(vidh->lnum); |
| |
| /* Unsupported internal volume */ |
| switch (vidh->compat) { |
| case UBI_COMPAT_DELETE: |
| ubi_msg("\"delete\" compatible internal volume %d:%d" |
| " found, remove it", vol_id, lnum); |
| err = add_to_list(si, pnum, ec, &si->corr); |
| if (err) |
| return err; |
| break; |
| |
| case UBI_COMPAT_RO: |
| ubi_msg("read-only compatible internal volume %d:%d" |
| " found, switch to read-only mode", |
| vol_id, lnum); |
| ubi->ro_mode = 1; |
| break; |
| |
| case UBI_COMPAT_PRESERVE: |
| ubi_msg("\"preserve\" compatible internal volume %d:%d" |
| " found", vol_id, lnum); |
| err = add_to_list(si, pnum, ec, &si->alien); |
| if (err) |
| return err; |
| si->alien_peb_count += 1; |
| return 0; |
| |
| case UBI_COMPAT_REJECT: |
| ubi_err("incompatible internal volume %d:%d found", |
| vol_id, lnum); |
| return -EINVAL; |
| } |
| } |
| |
| /* Both UBI headers seem to be fine */ |
| err = ubi_scan_add_used(ubi, si, pnum, ec, vidh, bitflips); |
| if (err) |
| return err; |
| |
| adjust_mean_ec: |
| if (!ec_corr) { |
| if (si->ec_sum + ec < ec) { |
| commit_to_mean_value(si); |
| si->ec_sum = 0; |
| si->ec_count = 0; |
| } else { |
| si->ec_sum += ec; |
| si->ec_count += 1; |
| } |
| |
| if (ec > si->max_ec) |
| si->max_ec = ec; |
| if (ec < si->min_ec) |
| si->min_ec = ec; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * ubi_scan - scan an MTD device. |
| * @ubi: UBI device description object |
| * |
| * This function does full scanning of an MTD device and returns complete |
| * information about it. In case of failure, an error code is returned. |
| */ |
| struct ubi_scan_info *ubi_scan(struct ubi_device *ubi) |
| { |
| int err, pnum; |
| struct rb_node *rb1, *rb2; |
| struct ubi_scan_volume *sv; |
| struct ubi_scan_leb *seb; |
| struct ubi_scan_info *si; |
| |
| si = kzalloc(sizeof(struct ubi_scan_info), GFP_KERNEL); |
| if (!si) |
| return ERR_PTR(-ENOMEM); |
| |
| INIT_LIST_HEAD(&si->corr); |
| INIT_LIST_HEAD(&si->free); |
| INIT_LIST_HEAD(&si->erase); |
| INIT_LIST_HEAD(&si->alien); |
| si->volumes = RB_ROOT; |
| si->is_empty = 1; |
| |
| err = -ENOMEM; |
| ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| if (!ech) |
| goto out_si; |
| |
| vidh = ubi_zalloc_vid_hdr(ubi); |
| if (!vidh) |
| goto out_ech; |
| |
| for (pnum = 0; pnum < ubi->peb_count; pnum++) { |
| cond_resched(); |
| |
| dbg_msg("process PEB %d", pnum); |
| err = process_eb(ubi, si, pnum); |
| if (err < 0) |
| goto out_vidh; |
| } |
| |
| dbg_msg("scanning is finished"); |
| |
| /* Finish mean erase counter calculations */ |
| if (si->ec_count) |
| commit_to_mean_value(si); |
| |
| if (si->is_empty) |
| ubi_msg("empty MTD device detected"); |
| |
| /* |
| * In case of unknown erase counter we use the mean erase counter |
| * value. |
| */ |
| ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) { |
| ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) |
| if (seb->ec == UBI_SCAN_UNKNOWN_EC) |
| seb->ec = si->mean_ec; |
| } |
| |
| list_for_each_entry(seb, &si->free, u.list) { |
| if (seb->ec == UBI_SCAN_UNKNOWN_EC) |
| seb->ec = si->mean_ec; |
| } |
| |
| list_for_each_entry(seb, &si->corr, u.list) |
| if (seb->ec == UBI_SCAN_UNKNOWN_EC) |
| seb->ec = si->mean_ec; |
| |
| list_for_each_entry(seb, &si->erase, u.list) |
| if (seb->ec == UBI_SCAN_UNKNOWN_EC) |
| seb->ec = si->mean_ec; |
| |
| err = paranoid_check_si(ubi, si); |
| if (err) { |
| if (err > 0) |
| err = -EINVAL; |
| goto out_vidh; |
| } |
| |
| ubi_free_vid_hdr(ubi, vidh); |
| kfree(ech); |
| |
| return si; |
| |
| out_vidh: |
| ubi_free_vid_hdr(ubi, vidh); |
| out_ech: |
| kfree(ech); |
| out_si: |
| ubi_scan_destroy_si(si); |
| return ERR_PTR(err); |
| } |
| |
| /** |
| * destroy_sv - free the scanning volume information |
| * @sv: scanning volume information |
| * |
| * This function destroys the volume RB-tree (@sv->root) and the scanning |
| * volume information. |
| */ |
| static void destroy_sv(struct ubi_scan_volume *sv) |
| { |
| struct ubi_scan_leb *seb; |
| struct rb_node *this = sv->root.rb_node; |
| |
| while (this) { |
| if (this->rb_left) |
| this = this->rb_left; |
| else if (this->rb_right) |
| this = this->rb_right; |
| else { |
| seb = rb_entry(this, struct ubi_scan_leb, u.rb); |
| this = rb_parent(this); |
| if (this) { |
| if (this->rb_left == &seb->u.rb) |
| this->rb_left = NULL; |
| else |
| this->rb_right = NULL; |
| } |
| |
| kfree(seb); |
| } |
| } |
| kfree(sv); |
| } |
| |
| /** |
| * ubi_scan_destroy_si - destroy scanning information. |
| * @si: scanning information |
| */ |
| void ubi_scan_destroy_si(struct ubi_scan_info *si) |
| { |
| struct ubi_scan_leb *seb, *seb_tmp; |
| struct ubi_scan_volume *sv; |
| struct rb_node *rb; |
| |
| list_for_each_entry_safe(seb, seb_tmp, &si->alien, u.list) { |
| list_del(&seb->u.list); |
| kfree(seb); |
| } |
| list_for_each_entry_safe(seb, seb_tmp, &si->erase, u.list) { |
| list_del(&seb->u.list); |
| kfree(seb); |
| } |
| list_for_each_entry_safe(seb, seb_tmp, &si->corr, u.list) { |
| list_del(&seb->u.list); |
| kfree(seb); |
| } |
| list_for_each_entry_safe(seb, seb_tmp, &si->free, u.list) { |
| list_del(&seb->u.list); |
| kfree(seb); |
| } |
| |
| /* Destroy the volume RB-tree */ |
| rb = si->volumes.rb_node; |
| while (rb) { |
| if (rb->rb_left) |
| rb = rb->rb_left; |
| else if (rb->rb_right) |
| rb = rb->rb_right; |
| else { |
| sv = rb_entry(rb, struct ubi_scan_volume, rb); |
| |
| rb = rb_parent(rb); |
| if (rb) { |
| if (rb->rb_left == &sv->rb) |
| rb->rb_left = NULL; |
| else |
| rb->rb_right = NULL; |
| } |
| |
| destroy_sv(sv); |
| } |
| } |
| |
| kfree(si); |
| } |
| |
| #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID |
| |
| /** |
| * paranoid_check_si - check if the scanning information is correct and |
| * consistent. |
| * @ubi: UBI device description object |
| * @si: scanning information |
| * |
| * This function returns zero if the scanning information is all right, %1 if |
| * not and a negative error code if an error occurred. |
| */ |
| static int paranoid_check_si(const struct ubi_device *ubi, |
| struct ubi_scan_info *si) |
| { |
| int pnum, err, vols_found = 0; |
| struct rb_node *rb1, *rb2; |
| struct ubi_scan_volume *sv; |
| struct ubi_scan_leb *seb, *last_seb; |
| uint8_t *buf; |
| |
| /* |
| * At first, check that scanning information is OK. |
| */ |
| ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) { |
| int leb_count = 0; |
| |
| cond_resched(); |
| |
| vols_found += 1; |
| |
| if (si->is_empty) { |
| ubi_err("bad is_empty flag"); |
| goto bad_sv; |
| } |
| |
| if (sv->vol_id < 0 || sv->highest_lnum < 0 || |
| sv->leb_count < 0 || sv->vol_type < 0 || sv->used_ebs < 0 || |
| sv->data_pad < 0 || sv->last_data_size < 0) { |
| ubi_err("negative values"); |
| goto bad_sv; |
| } |
| |
| if (sv->vol_id >= UBI_MAX_VOLUMES && |
| sv->vol_id < UBI_INTERNAL_VOL_START) { |
| ubi_err("bad vol_id"); |
| goto bad_sv; |
| } |
| |
| if (sv->vol_id > si->highest_vol_id) { |
| ubi_err("highest_vol_id is %d, but vol_id %d is there", |
| si->highest_vol_id, sv->vol_id); |
| goto out; |
| } |
| |
| if (sv->vol_type != UBI_DYNAMIC_VOLUME && |
| sv->vol_type != UBI_STATIC_VOLUME) { |
| ubi_err("bad vol_type"); |
| goto bad_sv; |
| } |
| |
| if (sv->data_pad > ubi->leb_size / 2) { |
| ubi_err("bad data_pad"); |
| goto bad_sv; |
| } |
| |
| last_seb = NULL; |
| ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) { |
| cond_resched(); |
| |
| last_seb = seb; |
| leb_count += 1; |
| |
| if (seb->pnum < 0 || seb->ec < 0) { |
| ubi_err("negative values"); |
| goto bad_seb; |
| } |
| |
| if (seb->ec < si->min_ec) { |
| ubi_err("bad si->min_ec (%d), %d found", |
| si->min_ec, seb->ec); |
| goto bad_seb; |
| } |
| |
| if (seb->ec > si->max_ec) { |
| ubi_err("bad si->max_ec (%d), %d found", |
| si->max_ec, seb->ec); |
| goto bad_seb; |
| } |
| |
| if (seb->pnum >= ubi->peb_count) { |
| ubi_err("too high PEB number %d, total PEBs %d", |
| seb->pnum, ubi->peb_count); |
| goto bad_seb; |
| } |
| |
| if (sv->vol_type == UBI_STATIC_VOLUME) { |
| if (seb->lnum >= sv->used_ebs) { |
| ubi_err("bad lnum or used_ebs"); |
| goto bad_seb; |
| } |
| } else { |
| if (sv->used_ebs != 0) { |
| ubi_err("non-zero used_ebs"); |
| goto bad_seb; |
| } |
| } |
| |
| if (seb->lnum > sv->highest_lnum) { |
| ubi_err("incorrect highest_lnum or lnum"); |
| goto bad_seb; |
| } |
| } |
| |
| if (sv->leb_count != leb_count) { |
| ubi_err("bad leb_count, %d objects in the tree", |
| leb_count); |
| goto bad_sv; |
| } |
| |
| if (!last_seb) |
| continue; |
| |
| seb = last_seb; |
| |
| if (seb->lnum != sv->highest_lnum) { |
| ubi_err("bad highest_lnum"); |
| goto bad_seb; |
| } |
| } |
| |
| if (vols_found != si->vols_found) { |
| ubi_err("bad si->vols_found %d, should be %d", |
| si->vols_found, vols_found); |
| goto out; |
| } |
| |
| /* Check that scanning information is correct */ |
| ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) { |
| last_seb = NULL; |
| ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) { |
| int vol_type; |
| |
| cond_resched(); |
| |
| last_seb = seb; |
| |
| err = ubi_io_read_vid_hdr(ubi, seb->pnum, vidh, 1); |
| if (err && err != UBI_IO_BITFLIPS) { |
| ubi_err("VID header is not OK (%d)", err); |
| if (err > 0) |
| err = -EIO; |
| return err; |
| } |
| |
| vol_type = vidh->vol_type == UBI_VID_DYNAMIC ? |
| UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME; |
| if (sv->vol_type != vol_type) { |
| ubi_err("bad vol_type"); |
| goto bad_vid_hdr; |
| } |
| |
| if (seb->sqnum != ubi64_to_cpu(vidh->sqnum)) { |
| ubi_err("bad sqnum %llu", seb->sqnum); |
| goto bad_vid_hdr; |
| } |
| |
| if (sv->vol_id != ubi32_to_cpu(vidh->vol_id)) { |
| ubi_err("bad vol_id %d", sv->vol_id); |
| goto bad_vid_hdr; |
| } |
| |
| if (sv->compat != vidh->compat) { |
| ubi_err("bad compat %d", vidh->compat); |
| goto bad_vid_hdr; |
| } |
| |
| if (seb->lnum != ubi32_to_cpu(vidh->lnum)) { |
| ubi_err("bad lnum %d", seb->lnum); |
| goto bad_vid_hdr; |
| } |
| |
| if (sv->used_ebs != ubi32_to_cpu(vidh->used_ebs)) { |
| ubi_err("bad used_ebs %d", sv->used_ebs); |
| goto bad_vid_hdr; |
| } |
| |
| if (sv->data_pad != ubi32_to_cpu(vidh->data_pad)) { |
| ubi_err("bad data_pad %d", sv->data_pad); |
| goto bad_vid_hdr; |
| } |
| |
| if (seb->leb_ver != ubi32_to_cpu(vidh->leb_ver)) { |
| ubi_err("bad leb_ver %u", seb->leb_ver); |
| goto bad_vid_hdr; |
| } |
| } |
| |
| if (!last_seb) |
| continue; |
| |
| if (sv->highest_lnum != ubi32_to_cpu(vidh->lnum)) { |
| ubi_err("bad highest_lnum %d", sv->highest_lnum); |
| goto bad_vid_hdr; |
| } |
| |
| if (sv->last_data_size != ubi32_to_cpu(vidh->data_size)) { |
| ubi_err("bad last_data_size %d", sv->last_data_size); |
| goto bad_vid_hdr; |
| } |
| } |
| |
| /* |
| * Make sure that all the physical eraseblocks are in one of the lists |
| * or trees. |
| */ |
| buf = kmalloc(ubi->peb_count, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| memset(buf, 1, ubi->peb_count); |
| for (pnum = 0; pnum < ubi->peb_count; pnum++) { |
| err = ubi_io_is_bad(ubi, pnum); |
| if (err < 0) { |
| kfree(buf); |
| return err; |
| } |
| else if (err) |
| buf[pnum] = 0; |
| } |
| |
| ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) |
| ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) |
| buf[seb->pnum] = 0; |
| |
| list_for_each_entry(seb, &si->free, u.list) |
| buf[seb->pnum] = 0; |
| |
| list_for_each_entry(seb, &si->corr, u.list) |
| buf[seb->pnum] = 0; |
| |
| list_for_each_entry(seb, &si->erase, u.list) |
| buf[seb->pnum] = 0; |
| |
| list_for_each_entry(seb, &si->alien, u.list) |
| buf[seb->pnum] = 0; |
| |
| err = 0; |
| for (pnum = 0; pnum < ubi->peb_count; pnum++) |
| if (buf[pnum]) { |
| ubi_err("PEB %d is not referred", pnum); |
| err = 1; |
| } |
| |
| kfree(buf); |
| if (err) |
| goto out; |
| return 0; |
| |
| bad_seb: |
| ubi_err("bad scanning information about LEB %d", seb->lnum); |
| ubi_dbg_dump_seb(seb, 0); |
| ubi_dbg_dump_sv(sv); |
| goto out; |
| |
| bad_sv: |
| ubi_err("bad scanning information about volume %d", sv->vol_id); |
| ubi_dbg_dump_sv(sv); |
| goto out; |
| |
| bad_vid_hdr: |
| ubi_err("bad scanning information about volume %d", sv->vol_id); |
| ubi_dbg_dump_sv(sv); |
| ubi_dbg_dump_vid_hdr(vidh); |
| |
| out: |
| ubi_dbg_dump_stack(); |
| return 1; |
| } |
| |
| #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */ |