| /* |
| * Copyright (c) International Business Machines Corp., 2006 |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| * |
| * Author: Artem Bityutskiy (Битюцкий Артём) |
| */ |
| |
| /* |
| * UBI attaching sub-system. |
| * |
| * This sub-system is responsible for attaching MTD devices and it also |
| * implements flash media scanning. |
| * |
| * The attaching information is represented by a &struct ubi_attach_info' |
| * object. Information about volumes is represented by &struct ubi_ainf_volume |
| * objects which are kept in volume RB-tree with root at the @volumes field. |
| * The RB-tree is indexed by the volume ID. |
| * |
| * Logical eraseblocks are represented by &struct ubi_ainf_peb objects. These |
| * objects are kept in per-volume RB-trees with the root at the corresponding |
| * &struct ubi_ainf_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-LEB 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. |
| * |
| * About corruptions |
| * ~~~~~~~~~~~~~~~~~ |
| * |
| * UBI protects EC and VID headers with CRC-32 checksums, so it can detect |
| * whether the headers are corrupted or not. Sometimes UBI also protects the |
| * data with CRC-32, e.g., when it executes the atomic LEB change operation, or |
| * when it moves the contents of a PEB for wear-leveling purposes. |
| * |
| * UBI tries to distinguish between 2 types of corruptions. |
| * |
| * 1. Corruptions caused by power cuts. These are expected corruptions and UBI |
| * tries to handle them gracefully, without printing too many warnings and |
| * error messages. The idea is that we do not lose important data in these |
| * cases - we may lose only the data which were being written to the media just |
| * before the power cut happened, and the upper layers (e.g., UBIFS) are |
| * supposed to handle such data losses (e.g., by using the FS journal). |
| * |
| * When UBI detects a corruption (CRC-32 mismatch) in a PEB, and it looks like |
| * the reason is a power cut, UBI puts this PEB to the @erase list, and all |
| * PEBs in the @erase list are scheduled for erasure later. |
| * |
| * 2. Unexpected corruptions which are not caused by power cuts. During |
| * attaching, such PEBs are put to the @corr list and UBI preserves them. |
| * Obviously, this lessens the amount of available PEBs, and if at some point |
| * UBI runs out of free PEBs, it switches to R/O mode. UBI also loudly informs |
| * about such PEBs every time the MTD device is attached. |
| * |
| * However, it is difficult to reliably distinguish between these types of |
| * corruptions and UBI's strategy is as follows (in case of attaching by |
| * scanning). UBI assumes corruption type 2 if the VID header is corrupted and |
| * the data area does not contain all 0xFFs, and there were no bit-flips or |
| * integrity errors (e.g., ECC errors in case of NAND) while reading the data |
| * area. Otherwise UBI assumes corruption type 1. So the decision criteria |
| * are as follows. |
| * o If the data area contains only 0xFFs, there are no data, and it is safe |
| * to just erase this PEB - this is corruption type 1. |
| * o If the data area has bit-flips or data integrity errors (ECC errors on |
| * NAND), it is probably a PEB which was being erased when power cut |
| * happened, so this is corruption type 1. However, this is just a guess, |
| * which might be wrong. |
| * o Otherwise this is corruption type 2. |
| */ |
| |
| #ifndef __UBOOT__ |
| #include <linux/err.h> |
| #include <linux/slab.h> |
| #include <linux/crc32.h> |
| #include <linux/random.h> |
| #else |
| #include <div64.h> |
| #include <linux/err.h> |
| #endif |
| |
| #include <linux/math64.h> |
| |
| #include <ubi_uboot.h> |
| #include "ubi.h" |
| |
| static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai); |
| |
| /* 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. |
| * @ai: attaching information |
| * @pnum: physical eraseblock number to add |
| * @vol_id: the last used volume id for the PEB |
| * @lnum: the last used LEB number for the PEB |
| * @ec: erase counter of the physical eraseblock |
| * @to_head: if not zero, add to the head of the list |
| * @list: the list to add to |
| * |
| * This function allocates a 'struct ubi_ainf_peb' object for physical |
| * eraseblock @pnum and adds it to the "free", "erase", or "alien" lists. |
| * It stores the @lnum and @vol_id alongside, which can both be |
| * %UBI_UNKNOWN if they are not available, not readable, or not assigned. |
| * If @to_head is not zero, PEB will be added to the head of the list, which |
| * basically means it will be processed first later. E.g., we add corrupted |
| * PEBs (corrupted due to power cuts) to the head of the erase list to make |
| * sure we erase them first and get rid of corruptions ASAP. This function |
| * returns zero in case of success and a negative error code in case of |
| * failure. |
| */ |
| static int add_to_list(struct ubi_attach_info *ai, int pnum, int vol_id, |
| int lnum, int ec, int to_head, struct list_head *list) |
| { |
| struct ubi_ainf_peb *aeb; |
| |
| if (list == &ai->free) { |
| dbg_bld("add to free: PEB %d, EC %d", pnum, ec); |
| } else if (list == &ai->erase) { |
| dbg_bld("add to erase: PEB %d, EC %d", pnum, ec); |
| } else if (list == &ai->alien) { |
| dbg_bld("add to alien: PEB %d, EC %d", pnum, ec); |
| ai->alien_peb_count += 1; |
| } else |
| BUG(); |
| |
| aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| if (!aeb) |
| return -ENOMEM; |
| |
| aeb->pnum = pnum; |
| aeb->vol_id = vol_id; |
| aeb->lnum = lnum; |
| aeb->ec = ec; |
| if (to_head) |
| list_add(&aeb->u.list, list); |
| else |
| list_add_tail(&aeb->u.list, list); |
| return 0; |
| } |
| |
| /** |
| * add_corrupted - add a corrupted physical eraseblock. |
| * @ai: attaching information |
| * @pnum: physical eraseblock number to add |
| * @ec: erase counter of the physical eraseblock |
| * |
| * This function allocates a 'struct ubi_ainf_peb' object for a corrupted |
| * physical eraseblock @pnum and adds it to the 'corr' list. The corruption |
| * was presumably not caused by a power cut. Returns zero in case of success |
| * and a negative error code in case of failure. |
| */ |
| static int add_corrupted(struct ubi_attach_info *ai, int pnum, int ec) |
| { |
| struct ubi_ainf_peb *aeb; |
| |
| dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec); |
| |
| aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| if (!aeb) |
| return -ENOMEM; |
| |
| ai->corr_peb_count += 1; |
| aeb->pnum = pnum; |
| aeb->ec = ec; |
| list_add(&aeb->u.list, &ai->corr); |
| return 0; |
| } |
| |
| /** |
| * validate_vid_hdr - check volume identifier header. |
| * @ubi: UBI device description object |
| * @vid_hdr: the volume identifier header to check |
| * @av: 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 sub-system. 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_device *ubi, |
| const struct ubi_vid_hdr *vid_hdr, |
| const struct ubi_ainf_volume *av, int pnum) |
| { |
| int vol_type = vid_hdr->vol_type; |
| int vol_id = be32_to_cpu(vid_hdr->vol_id); |
| int used_ebs = be32_to_cpu(vid_hdr->used_ebs); |
| int data_pad = be32_to_cpu(vid_hdr->data_pad); |
| |
| if (av->leb_count != 0) { |
| int av_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 != av->vol_id) { |
| ubi_err(ubi, "inconsistent vol_id"); |
| goto bad; |
| } |
| |
| if (av->vol_type == UBI_STATIC_VOLUME) |
| av_vol_type = UBI_VID_STATIC; |
| else |
| av_vol_type = UBI_VID_DYNAMIC; |
| |
| if (vol_type != av_vol_type) { |
| ubi_err(ubi, "inconsistent vol_type"); |
| goto bad; |
| } |
| |
| if (used_ebs != av->used_ebs) { |
| ubi_err(ubi, "inconsistent used_ebs"); |
| goto bad; |
| } |
| |
| if (data_pad != av->data_pad) { |
| ubi_err(ubi, "inconsistent data_pad"); |
| goto bad; |
| } |
| } |
| |
| return 0; |
| |
| bad: |
| ubi_err(ubi, "inconsistent VID header at PEB %d", pnum); |
| ubi_dump_vid_hdr(vid_hdr); |
| ubi_dump_av(av); |
| return -EINVAL; |
| } |
| |
| /** |
| * add_volume - add volume to the attaching information. |
| * @ai: attaching 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 attaching information, this function does nothing. Otherwise |
| * it adds corresponding volume to the attaching information. Returns a pointer |
| * to the allocated "av" object in case of success and a negative error code in |
| * case of failure. |
| */ |
| static struct ubi_ainf_volume *add_volume(struct ubi_attach_info *ai, |
| int vol_id, int pnum, |
| const struct ubi_vid_hdr *vid_hdr) |
| { |
| struct ubi_ainf_volume *av; |
| struct rb_node **p = &ai->volumes.rb_node, *parent = NULL; |
| |
| ubi_assert(vol_id == be32_to_cpu(vid_hdr->vol_id)); |
| |
| /* Walk the volume RB-tree to look if this volume is already present */ |
| while (*p) { |
| parent = *p; |
| av = rb_entry(parent, struct ubi_ainf_volume, rb); |
| |
| if (vol_id == av->vol_id) |
| return av; |
| |
| if (vol_id > av->vol_id) |
| p = &(*p)->rb_left; |
| else |
| p = &(*p)->rb_right; |
| } |
| |
| /* The volume is absent - add it */ |
| av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL); |
| if (!av) |
| return ERR_PTR(-ENOMEM); |
| |
| av->highest_lnum = av->leb_count = 0; |
| av->vol_id = vol_id; |
| av->root = RB_ROOT; |
| av->used_ebs = be32_to_cpu(vid_hdr->used_ebs); |
| av->data_pad = be32_to_cpu(vid_hdr->data_pad); |
| av->compat = vid_hdr->compat; |
| av->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME |
| : UBI_STATIC_VOLUME; |
| if (vol_id > ai->highest_vol_id) |
| ai->highest_vol_id = vol_id; |
| |
| rb_link_node(&av->rb, parent, p); |
| rb_insert_color(&av->rb, &ai->volumes); |
| ai->vols_found += 1; |
| dbg_bld("added volume %d", vol_id); |
| return av; |
| } |
| |
| /** |
| * ubi_compare_lebs - find out which logical eraseblock is newer. |
| * @ubi: UBI device description object |
| * @aeb: 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 @aeb) is newer than 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. |
| */ |
| int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb, |
| int pnum, const struct ubi_vid_hdr *vid_hdr) |
| { |
| int len, err, second_is_newer, bitflips = 0, corrupted = 0; |
| uint32_t data_crc, crc; |
| struct ubi_vid_hdr *vh = NULL; |
| unsigned long long sqnum2 = be64_to_cpu(vid_hdr->sqnum); |
| |
| if (sqnum2 == aeb->sqnum) { |
| /* |
| * This must be a really ancient UBI image which has been |
| * created before sequence numbers support has been added. At |
| * that times we used 32-bit LEB versions stored in logical |
| * eraseblocks. That was before UBI got into mainline. We do not |
| * support these images anymore. Well, those images still work, |
| * but only if no unclean reboots happened. |
| */ |
| ubi_err(ubi, "unsupported on-flash UBI format"); |
| return -EINVAL; |
| } |
| |
| /* Obviously the LEB with lower sequence counter is older */ |
| second_is_newer = (sqnum2 > aeb->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. |
| * |
| * Note: 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 { |
| if (!aeb->copy_flag) { |
| /* It is not a copy, so it is newer */ |
| dbg_bld("first PEB %d is newer, copy_flag is unset", |
| pnum); |
| return bitflips << 1; |
| } |
| |
| vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
| if (!vh) |
| return -ENOMEM; |
| |
| pnum = aeb->pnum; |
| err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0); |
| if (err) { |
| if (err == UBI_IO_BITFLIPS) |
| bitflips = 1; |
| else { |
| ubi_err(ubi, "VID of PEB %d header is bad, but it was OK earlier, err %d", |
| pnum, err); |
| if (err > 0) |
| err = -EIO; |
| |
| goto out_free_vidh; |
| } |
| } |
| |
| vid_hdr = vh; |
| } |
| |
| /* Read the data of the copy and check the CRC */ |
| |
| len = be32_to_cpu(vid_hdr->data_size); |
| |
| mutex_lock(&ubi->buf_mutex); |
| err = ubi_io_read_data(ubi, ubi->peb_buf, pnum, 0, len); |
| if (err && err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err)) |
| goto out_unlock; |
| |
| data_crc = be32_to_cpu(vid_hdr->data_crc); |
| crc = crc32(UBI_CRC32_INIT, ubi->peb_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; |
| } |
| mutex_unlock(&ubi->buf_mutex); |
| |
| ubi_free_vid_hdr(ubi, vh); |
| |
| 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_unlock: |
| mutex_unlock(&ubi->buf_mutex); |
| out_free_vidh: |
| ubi_free_vid_hdr(ubi, vh); |
| return err; |
| } |
| |
| /** |
| * ubi_add_to_av - add used physical eraseblock to the attaching information. |
| * @ubi: UBI device description object |
| * @ai: attaching 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 adds information about a used physical eraseblock to the |
| * 'used' tree of the corresponding volume. The function is rather complex |
| * because it has to handle cases when this is not the first physical |
| * eraseblock belonging to the same logical eraseblock, and the newer one has |
| * to be picked, while the older one has to be dropped. This function returns |
| * zero in case of success and a negative error code in case of failure. |
| */ |
| int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum, |
| int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips) |
| { |
| int err, vol_id, lnum; |
| unsigned long long sqnum; |
| struct ubi_ainf_volume *av; |
| struct ubi_ainf_peb *aeb; |
| struct rb_node **p, *parent = NULL; |
| |
| vol_id = be32_to_cpu(vid_hdr->vol_id); |
| lnum = be32_to_cpu(vid_hdr->lnum); |
| sqnum = be64_to_cpu(vid_hdr->sqnum); |
| |
| dbg_bld("PEB %d, LEB %d:%d, EC %d, sqnum %llu, bitflips %d", |
| pnum, vol_id, lnum, ec, sqnum, bitflips); |
| |
| av = add_volume(ai, vol_id, pnum, vid_hdr); |
| if (IS_ERR(av)) |
| return PTR_ERR(av); |
| |
| if (ai->max_sqnum < sqnum) |
| ai->max_sqnum = sqnum; |
| |
| /* |
| * 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 = &av->root.rb_node; |
| while (*p) { |
| int cmp_res; |
| |
| parent = *p; |
| aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb); |
| if (lnum != aeb->lnum) { |
| if (lnum < aeb->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, EC %d", |
| aeb->pnum, aeb->sqnum, aeb->ec); |
| |
| /* |
| * Make sure that the logical eraseblocks have different |
| * sequence numbers. Otherwise the image is bad. |
| * |
| * However, if the sequence number is zero, we assume it must |
| * be an ancient UBI image from the era when UBI did not have |
| * sequence numbers. We still can attach these images, unless |
| * there is a need to distinguish between old and new |
| * eraseblocks, in which case we'll refuse the image in |
| * 'ubi_compare_lebs()'. In other words, we attach old clean |
| * images, but refuse attaching old images with duplicated |
| * logical eraseblocks because there was an unclean reboot. |
| */ |
| if (aeb->sqnum == sqnum && sqnum != 0) { |
| ubi_err(ubi, "two LEBs with same sequence number %llu", |
| sqnum); |
| ubi_dump_aeb(aeb, 0); |
| ubi_dump_vid_hdr(vid_hdr); |
| return -EINVAL; |
| } |
| |
| /* |
| * Now we have to drop the older one and preserve the newer |
| * one. |
| */ |
| cmp_res = ubi_compare_lebs(ubi, aeb, pnum, vid_hdr); |
| if (cmp_res < 0) |
| return cmp_res; |
| |
| if (cmp_res & 1) { |
| /* |
| * This logical eraseblock is newer than the one |
| * found earlier. |
| */ |
| err = validate_vid_hdr(ubi, vid_hdr, av, pnum); |
| if (err) |
| return err; |
| |
| err = add_to_list(ai, aeb->pnum, aeb->vol_id, |
| aeb->lnum, aeb->ec, cmp_res & 4, |
| &ai->erase); |
| if (err) |
| return err; |
| |
| aeb->ec = ec; |
| aeb->pnum = pnum; |
| aeb->vol_id = vol_id; |
| aeb->lnum = lnum; |
| aeb->scrub = ((cmp_res & 2) || bitflips); |
| aeb->copy_flag = vid_hdr->copy_flag; |
| aeb->sqnum = sqnum; |
| |
| if (av->highest_lnum == lnum) |
| av->last_data_size = |
| be32_to_cpu(vid_hdr->data_size); |
| |
| return 0; |
| } else { |
| /* |
| * This logical eraseblock is older than the one found |
| * previously. |
| */ |
| return add_to_list(ai, pnum, vol_id, lnum, ec, |
| cmp_res & 4, &ai->erase); |
| } |
| } |
| |
| /* |
| * We've met this logical eraseblock for the first time, add it to the |
| * attaching information. |
| */ |
| |
| err = validate_vid_hdr(ubi, vid_hdr, av, pnum); |
| if (err) |
| return err; |
| |
| aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| if (!aeb) |
| return -ENOMEM; |
| |
| aeb->ec = ec; |
| aeb->pnum = pnum; |
| aeb->vol_id = vol_id; |
| aeb->lnum = lnum; |
| aeb->scrub = bitflips; |
| aeb->copy_flag = vid_hdr->copy_flag; |
| aeb->sqnum = sqnum; |
| |
| if (av->highest_lnum <= lnum) { |
| av->highest_lnum = lnum; |
| av->last_data_size = be32_to_cpu(vid_hdr->data_size); |
| } |
| |
| av->leb_count += 1; |
| rb_link_node(&aeb->u.rb, parent, p); |
| rb_insert_color(&aeb->u.rb, &av->root); |
| return 0; |
| } |
| |
| /** |
| * ubi_find_av - find volume in the attaching information. |
| * @ai: attaching 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 attaching information. |
| */ |
| struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai, |
| int vol_id) |
| { |
| struct ubi_ainf_volume *av; |
| struct rb_node *p = ai->volumes.rb_node; |
| |
| while (p) { |
| av = rb_entry(p, struct ubi_ainf_volume, rb); |
| |
| if (vol_id == av->vol_id) |
| return av; |
| |
| if (vol_id > av->vol_id) |
| p = p->rb_left; |
| else |
| p = p->rb_right; |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * ubi_remove_av - delete attaching information about a volume. |
| * @ai: attaching information |
| * @av: the volume attaching information to delete |
| */ |
| void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av) |
| { |
| struct rb_node *rb; |
| struct ubi_ainf_peb *aeb; |
| |
| dbg_bld("remove attaching information about volume %d", av->vol_id); |
| |
| while ((rb = rb_first(&av->root))) { |
| aeb = rb_entry(rb, struct ubi_ainf_peb, u.rb); |
| rb_erase(&aeb->u.rb, &av->root); |
| list_add_tail(&aeb->u.list, &ai->erase); |
| } |
| |
| rb_erase(&av->rb, &ai->volumes); |
| kfree(av); |
| ai->vols_found -= 1; |
| } |
| |
| /** |
| * early_erase_peb - erase a physical eraseblock. |
| * @ubi: UBI device description object |
| * @ai: attaching information |
| * @pnum: physical eraseblock number to erase; |
| * @ec: erase counter value to write (%UBI_UNKNOWN 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 sub-system had not been yet initialized. |
| * This function returns zero in case of success and a negative error code in |
| * case of failure. |
| */ |
| static int early_erase_peb(struct ubi_device *ubi, |
| const struct ubi_attach_info *ai, int pnum, int ec) |
| { |
| int err; |
| struct ubi_ec_hdr *ec_hdr; |
| |
| if ((long long)ec >= UBI_MAX_ERASECOUNTER) { |
| /* |
| * Erase counter overflow. Upgrade UBI and use 64-bit |
| * erase counters internally. |
| */ |
| ubi_err(ubi, "erase counter overflow at PEB %d, EC %d", |
| pnum, ec); |
| return -EINVAL; |
| } |
| |
| ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| if (!ec_hdr) |
| return -ENOMEM; |
| |
| ec_hdr->ec = cpu_to_be64(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_early_get_peb - get a free physical eraseblock. |
| * @ubi: UBI device description object |
| * @ai: attaching information |
| * |
| * This function returns a free physical eraseblock. It is supposed to be |
| * called on the UBI initialization stages when the wear-leveling sub-system 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 a pointer to the "aeb" of the found free PEB in case |
| * of success and an error code in case of failure. |
| */ |
| struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi, |
| struct ubi_attach_info *ai) |
| { |
| int err = 0; |
| struct ubi_ainf_peb *aeb, *tmp_aeb; |
| |
| if (!list_empty(&ai->free)) { |
| aeb = list_entry(ai->free.next, struct ubi_ainf_peb, u.list); |
| list_del(&aeb->u.list); |
| dbg_bld("return free PEB %d, EC %d", aeb->pnum, aeb->ec); |
| return aeb; |
| } |
| |
| /* |
| * We try to erase the first physical eraseblock from the erase 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(aeb, tmp_aeb, &ai->erase, u.list) { |
| if (aeb->ec == UBI_UNKNOWN) |
| aeb->ec = ai->mean_ec; |
| |
| err = early_erase_peb(ubi, ai, aeb->pnum, aeb->ec+1); |
| if (err) |
| continue; |
| |
| aeb->ec += 1; |
| list_del(&aeb->u.list); |
| dbg_bld("return PEB %d, EC %d", aeb->pnum, aeb->ec); |
| return aeb; |
| } |
| |
| ubi_err(ubi, "no free eraseblocks"); |
| return ERR_PTR(-ENOSPC); |
| } |
| |
| /** |
| * check_corruption - check the data area of PEB. |
| * @ubi: UBI device description object |
| * @vid_hdr: the (corrupted) VID header of this PEB |
| * @pnum: the physical eraseblock number to check |
| * |
| * This is a helper function which is used to distinguish between VID header |
| * corruptions caused by power cuts and other reasons. If the PEB contains only |
| * 0xFF bytes in the data area, the VID header is most probably corrupted |
| * because of a power cut (%0 is returned in this case). Otherwise, it was |
| * probably corrupted for some other reasons (%1 is returned in this case). A |
| * negative error code is returned if a read error occurred. |
| * |
| * If the corruption reason was a power cut, UBI can safely erase this PEB. |
| * Otherwise, it should preserve it to avoid possibly destroying important |
| * information. |
| */ |
| static int check_corruption(struct ubi_device *ubi, struct ubi_vid_hdr *vid_hdr, |
| int pnum) |
| { |
| int err; |
| |
| mutex_lock(&ubi->buf_mutex); |
| memset(ubi->peb_buf, 0x00, ubi->leb_size); |
| |
| err = ubi_io_read(ubi, ubi->peb_buf, pnum, ubi->leb_start, |
| ubi->leb_size); |
| if (err == UBI_IO_BITFLIPS || mtd_is_eccerr(err)) { |
| /* |
| * Bit-flips or integrity errors while reading the data area. |
| * It is difficult to say for sure what type of corruption is |
| * this, but presumably a power cut happened while this PEB was |
| * erased, so it became unstable and corrupted, and should be |
| * erased. |
| */ |
| err = 0; |
| goto out_unlock; |
| } |
| |
| if (err) |
| goto out_unlock; |
| |
| if (ubi_check_pattern(ubi->peb_buf, 0xFF, ubi->leb_size)) |
| goto out_unlock; |
| |
| ubi_err(ubi, "PEB %d contains corrupted VID header, and the data does not contain all 0xFF", |
| pnum); |
| ubi_err(ubi, "this may be a non-UBI PEB or a severe VID header corruption which requires manual inspection"); |
| ubi_dump_vid_hdr(vid_hdr); |
| pr_err("hexdump of PEB %d offset %d, length %d", |
| pnum, ubi->leb_start, ubi->leb_size); |
| ubi_dbg_print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, |
| ubi->peb_buf, ubi->leb_size, 1); |
| err = 1; |
| |
| out_unlock: |
| mutex_unlock(&ubi->buf_mutex); |
| return err; |
| } |
| |
| /** |
| * scan_peb - scan and process UBI headers of a PEB. |
| * @ubi: UBI device description object |
| * @ai: attaching information |
| * @pnum: the physical eraseblock number |
| * @vid: The volume ID of the found volume will be stored in this pointer |
| * @sqnum: The sqnum of the found volume will be stored in this pointer |
| * |
| * This function reads UBI headers of PEB @pnum, checks them, and adds |
| * information about this PEB to the corresponding list or RB-tree in the |
| * "attaching info" structure. Returns zero if the physical eraseblock was |
| * successfully handled and a negative error code in case of failure. |
| */ |
| static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, |
| int pnum, int *vid, unsigned long long *sqnum) |
| { |
| long long uninitialized_var(ec); |
| int err, bitflips = 0, vol_id = -1, ec_err = 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) { |
| ai->bad_peb_count += 1; |
| return 0; |
| } |
| |
| err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0); |
| if (err < 0) |
| return err; |
| switch (err) { |
| case 0: |
| break; |
| case UBI_IO_BITFLIPS: |
| bitflips = 1; |
| break; |
| case UBI_IO_FF: |
| ai->empty_peb_count += 1; |
| return add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN, |
| UBI_UNKNOWN, 0, &ai->erase); |
| case UBI_IO_FF_BITFLIPS: |
| ai->empty_peb_count += 1; |
| return add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN, |
| UBI_UNKNOWN, 1, &ai->erase); |
| case UBI_IO_BAD_HDR_EBADMSG: |
| case UBI_IO_BAD_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_err = err; |
| ec = UBI_UNKNOWN; |
| bitflips = 1; |
| break; |
| default: |
| ubi_err(ubi, "'ubi_io_read_ec_hdr()' returned unknown code %d", |
| err); |
| return -EINVAL; |
| } |
| |
| if (!ec_err) { |
| int image_seq; |
| |
| /* Make sure UBI version is OK */ |
| if (ech->version != UBI_VERSION) { |
| ubi_err(ubi, "this UBI version is %d, image version is %d", |
| UBI_VERSION, (int)ech->version); |
| return -EINVAL; |
| } |
| |
| ec = be64_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(ubi, "erase counter overflow, max is %d", |
| UBI_MAX_ERASECOUNTER); |
| ubi_dump_ec_hdr(ech); |
| return -EINVAL; |
| } |
| |
| /* |
| * Make sure that all PEBs have the same image sequence number. |
| * This allows us to detect situations when users flash UBI |
| * images incorrectly, so that the flash has the new UBI image |
| * and leftovers from the old one. This feature was added |
| * relatively recently, and the sequence number was always |
| * zero, because old UBI implementations always set it to zero. |
| * For this reasons, we do not panic if some PEBs have zero |
| * sequence number, while other PEBs have non-zero sequence |
| * number. |
| */ |
| image_seq = be32_to_cpu(ech->image_seq); |
| if (!ubi->image_seq) |
| ubi->image_seq = image_seq; |
| if (image_seq && ubi->image_seq != image_seq) { |
| ubi_err(ubi, "bad image sequence number %d in PEB %d, expected %d", |
| image_seq, pnum, ubi->image_seq); |
| ubi_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; |
| switch (err) { |
| case 0: |
| break; |
| case UBI_IO_BITFLIPS: |
| bitflips = 1; |
| break; |
| case UBI_IO_BAD_HDR_EBADMSG: |
| if (ec_err == UBI_IO_BAD_HDR_EBADMSG) |
| /* |
| * Both EC and VID headers are corrupted and were read |
| * with data integrity error, probably this is a bad |
| * PEB, bit it is not marked as bad yet. This may also |
| * be a result of power cut during erasure. |
| */ |
| ai->maybe_bad_peb_count += 1; |
| case UBI_IO_BAD_HDR: |
| if (ec_err) |
| /* |
| * Both headers are corrupted. There is a possibility |
| * that this a valid UBI PEB which has corresponding |
| * LEB, but the headers are corrupted. However, it is |
| * impossible to distinguish it from a PEB which just |
| * contains garbage because of a power cut during erase |
| * operation. So we just schedule this PEB for erasure. |
| * |
| * Besides, in case of NOR flash, we deliberately |
| * corrupt both headers because NOR flash erasure is |
| * slow and can start from the end. |
| */ |
| err = 0; |
| else |
| /* |
| * The EC was OK, but the VID header is corrupted. We |
| * have to check what is in the data area. |
| */ |
| err = check_corruption(ubi, vidh, pnum); |
| |
| if (err < 0) |
| return err; |
| else if (!err) |
| /* This corruption is caused by a power cut */ |
| err = add_to_list(ai, pnum, UBI_UNKNOWN, |
| UBI_UNKNOWN, ec, 1, &ai->erase); |
| else |
| /* This is an unexpected corruption */ |
| err = add_corrupted(ai, pnum, ec); |
| if (err) |
| return err; |
| goto adjust_mean_ec; |
| case UBI_IO_FF_BITFLIPS: |
| err = add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN, |
| ec, 1, &ai->erase); |
| if (err) |
| return err; |
| goto adjust_mean_ec; |
| case UBI_IO_FF: |
| if (ec_err || bitflips) |
| err = add_to_list(ai, pnum, UBI_UNKNOWN, |
| UBI_UNKNOWN, ec, 1, &ai->erase); |
| else |
| err = add_to_list(ai, pnum, UBI_UNKNOWN, |
| UBI_UNKNOWN, ec, 0, &ai->free); |
| if (err) |
| return err; |
| goto adjust_mean_ec; |
| default: |
| ubi_err(ubi, "'ubi_io_read_vid_hdr()' returned unknown code %d", |
| err); |
| return -EINVAL; |
| } |
| |
| vol_id = be32_to_cpu(vidh->vol_id); |
| if (vid) |
| *vid = vol_id; |
| if (sqnum) |
| *sqnum = be64_to_cpu(vidh->sqnum); |
| if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOLUME_ID) { |
| int lnum = be32_to_cpu(vidh->lnum); |
| |
| /* Unsupported internal volume */ |
| switch (vidh->compat) { |
| case UBI_COMPAT_DELETE: |
| if (vol_id != UBI_FM_SB_VOLUME_ID |
| && vol_id != UBI_FM_DATA_VOLUME_ID) { |
| ubi_msg(ubi, "\"delete\" compatible internal volume %d:%d found, will remove it", |
| vol_id, lnum); |
| } |
| err = add_to_list(ai, pnum, vol_id, lnum, |
| ec, 1, &ai->erase); |
| if (err) |
| return err; |
| return 0; |
| |
| case UBI_COMPAT_RO: |
| ubi_msg(ubi, "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(ubi, "\"preserve\" compatible internal volume %d:%d found", |
| vol_id, lnum); |
| err = add_to_list(ai, pnum, vol_id, lnum, |
| ec, 0, &ai->alien); |
| if (err) |
| return err; |
| return 0; |
| |
| case UBI_COMPAT_REJECT: |
| ubi_err(ubi, "incompatible internal volume %d:%d found", |
| vol_id, lnum); |
| return -EINVAL; |
| } |
| } |
| |
| if (ec_err) |
| ubi_warn(ubi, "valid VID header but corrupted EC header at PEB %d", |
| pnum); |
| err = ubi_add_to_av(ubi, ai, pnum, ec, vidh, bitflips); |
| if (err) |
| return err; |
| |
| adjust_mean_ec: |
| if (!ec_err) { |
| ai->ec_sum += ec; |
| ai->ec_count += 1; |
| if (ec > ai->max_ec) |
| ai->max_ec = ec; |
| if (ec < ai->min_ec) |
| ai->min_ec = ec; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * late_analysis - analyze the overall situation with PEB. |
| * @ubi: UBI device description object |
| * @ai: attaching information |
| * |
| * This is a helper function which takes a look what PEBs we have after we |
| * gather information about all of them ("ai" is compete). It decides whether |
| * the flash is empty and should be formatted of whether there are too many |
| * corrupted PEBs and we should not attach this MTD device. Returns zero if we |
| * should proceed with attaching the MTD device, and %-EINVAL if we should not. |
| */ |
| static int late_analysis(struct ubi_device *ubi, struct ubi_attach_info *ai) |
| { |
| struct ubi_ainf_peb *aeb; |
| int max_corr, peb_count; |
| |
| peb_count = ubi->peb_count - ai->bad_peb_count - ai->alien_peb_count; |
| max_corr = peb_count / 20 ?: 8; |
| |
| /* |
| * Few corrupted PEBs is not a problem and may be just a result of |
| * unclean reboots. However, many of them may indicate some problems |
| * with the flash HW or driver. |
| */ |
| if (ai->corr_peb_count) { |
| ubi_err(ubi, "%d PEBs are corrupted and preserved", |
| ai->corr_peb_count); |
| pr_err("Corrupted PEBs are:"); |
| list_for_each_entry(aeb, &ai->corr, u.list) |
| pr_cont(" %d", aeb->pnum); |
| pr_cont("\n"); |
| |
| /* |
| * If too many PEBs are corrupted, we refuse attaching, |
| * otherwise, only print a warning. |
| */ |
| if (ai->corr_peb_count >= max_corr) { |
| ubi_err(ubi, "too many corrupted PEBs, refusing"); |
| return -EINVAL; |
| } |
| } |
| |
| if (ai->empty_peb_count + ai->maybe_bad_peb_count == peb_count) { |
| /* |
| * All PEBs are empty, or almost all - a couple PEBs look like |
| * they may be bad PEBs which were not marked as bad yet. |
| * |
| * This piece of code basically tries to distinguish between |
| * the following situations: |
| * |
| * 1. Flash is empty, but there are few bad PEBs, which are not |
| * marked as bad so far, and which were read with error. We |
| * want to go ahead and format this flash. While formatting, |
| * the faulty PEBs will probably be marked as bad. |
| * |
| * 2. Flash contains non-UBI data and we do not want to format |
| * it and destroy possibly important information. |
| */ |
| if (ai->maybe_bad_peb_count <= 2) { |
| ai->is_empty = 1; |
| ubi_msg(ubi, "empty MTD device detected"); |
| get_random_bytes(&ubi->image_seq, |
| sizeof(ubi->image_seq)); |
| } else { |
| ubi_err(ubi, "MTD device is not UBI-formatted and possibly contains non-UBI data - refusing it"); |
| return -EINVAL; |
| } |
| |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * destroy_av - free volume attaching information. |
| * @av: volume attaching information |
| * @ai: attaching information |
| * |
| * This function destroys the volume attaching information. |
| */ |
| static void destroy_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av) |
| { |
| struct ubi_ainf_peb *aeb; |
| struct rb_node *this = av->root.rb_node; |
| |
| while (this) { |
| if (this->rb_left) |
| this = this->rb_left; |
| else if (this->rb_right) |
| this = this->rb_right; |
| else { |
| aeb = rb_entry(this, struct ubi_ainf_peb, u.rb); |
| this = rb_parent(this); |
| if (this) { |
| if (this->rb_left == &aeb->u.rb) |
| this->rb_left = NULL; |
| else |
| this->rb_right = NULL; |
| } |
| |
| kmem_cache_free(ai->aeb_slab_cache, aeb); |
| } |
| } |
| kfree(av); |
| } |
| |
| /** |
| * destroy_ai - destroy attaching information. |
| * @ai: attaching information |
| */ |
| static void destroy_ai(struct ubi_attach_info *ai) |
| { |
| struct ubi_ainf_peb *aeb, *aeb_tmp; |
| struct ubi_ainf_volume *av; |
| struct rb_node *rb; |
| |
| list_for_each_entry_safe(aeb, aeb_tmp, &ai->alien, u.list) { |
| list_del(&aeb->u.list); |
| kmem_cache_free(ai->aeb_slab_cache, aeb); |
| } |
| list_for_each_entry_safe(aeb, aeb_tmp, &ai->erase, u.list) { |
| list_del(&aeb->u.list); |
| kmem_cache_free(ai->aeb_slab_cache, aeb); |
| } |
| list_for_each_entry_safe(aeb, aeb_tmp, &ai->corr, u.list) { |
| list_del(&aeb->u.list); |
| kmem_cache_free(ai->aeb_slab_cache, aeb); |
| } |
| list_for_each_entry_safe(aeb, aeb_tmp, &ai->free, u.list) { |
| list_del(&aeb->u.list); |
| kmem_cache_free(ai->aeb_slab_cache, aeb); |
| } |
| |
| /* Destroy the volume RB-tree */ |
| rb = ai->volumes.rb_node; |
| while (rb) { |
| if (rb->rb_left) |
| rb = rb->rb_left; |
| else if (rb->rb_right) |
| rb = rb->rb_right; |
| else { |
| av = rb_entry(rb, struct ubi_ainf_volume, rb); |
| |
| rb = rb_parent(rb); |
| if (rb) { |
| if (rb->rb_left == &av->rb) |
| rb->rb_left = NULL; |
| else |
| rb->rb_right = NULL; |
| } |
| |
| destroy_av(ai, av); |
| } |
| } |
| |
| kmem_cache_destroy(ai->aeb_slab_cache); |
| |
| kfree(ai); |
| } |
| |
| /** |
| * scan_all - scan entire MTD device. |
| * @ubi: UBI device description object |
| * @ai: attach info object |
| * @start: start scanning at this PEB |
| * |
| * This function does full scanning of an MTD device and returns complete |
| * information about it in form of a "struct ubi_attach_info" object. In case |
| * of failure, an error code is returned. |
| */ |
| static int scan_all(struct ubi_device *ubi, struct ubi_attach_info *ai, |
| int start) |
| { |
| int err, pnum; |
| struct rb_node *rb1, *rb2; |
| struct ubi_ainf_volume *av; |
| struct ubi_ainf_peb *aeb; |
| |
| err = -ENOMEM; |
| |
| ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| if (!ech) |
| return err; |
| |
| vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
| if (!vidh) |
| goto out_ech; |
| |
| for (pnum = start; pnum < ubi->peb_count; pnum++) { |
| cond_resched(); |
| |
| dbg_gen("process PEB %d", pnum); |
| err = scan_peb(ubi, ai, pnum, NULL, NULL); |
| if (err < 0) |
| goto out_vidh; |
| } |
| |
| ubi_msg(ubi, "scanning is finished"); |
| |
| /* Calculate mean erase counter */ |
| if (ai->ec_count) |
| ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count); |
| |
| err = late_analysis(ubi, ai); |
| if (err) |
| goto out_vidh; |
| |
| /* |
| * In case of unknown erase counter we use the mean erase counter |
| * value. |
| */ |
| ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
| ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) |
| if (aeb->ec == UBI_UNKNOWN) |
| aeb->ec = ai->mean_ec; |
| } |
| |
| list_for_each_entry(aeb, &ai->free, u.list) { |
| if (aeb->ec == UBI_UNKNOWN) |
| aeb->ec = ai->mean_ec; |
| } |
| |
| list_for_each_entry(aeb, &ai->corr, u.list) |
| if (aeb->ec == UBI_UNKNOWN) |
| aeb->ec = ai->mean_ec; |
| |
| list_for_each_entry(aeb, &ai->erase, u.list) |
| if (aeb->ec == UBI_UNKNOWN) |
| aeb->ec = ai->mean_ec; |
| |
| err = self_check_ai(ubi, ai); |
| if (err) |
| goto out_vidh; |
| |
| ubi_free_vid_hdr(ubi, vidh); |
| kfree(ech); |
| |
| return 0; |
| |
| out_vidh: |
| ubi_free_vid_hdr(ubi, vidh); |
| out_ech: |
| kfree(ech); |
| return err; |
| } |
| |
| static struct ubi_attach_info *alloc_ai(void) |
| { |
| struct ubi_attach_info *ai; |
| |
| ai = kzalloc(sizeof(struct ubi_attach_info), GFP_KERNEL); |
| if (!ai) |
| return ai; |
| |
| 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->aeb_slab_cache = kmem_cache_create("ubi_aeb_slab_cache", |
| sizeof(struct ubi_ainf_peb), |
| 0, 0, NULL); |
| if (!ai->aeb_slab_cache) { |
| kfree(ai); |
| ai = NULL; |
| } |
| |
| return ai; |
| } |
| |
| #ifdef CONFIG_MTD_UBI_FASTMAP |
| |
| /** |
| * scan_fastmap - try to find a fastmap and attach from it. |
| * @ubi: UBI device description object |
| * @ai: attach info object |
| * |
| * Returns 0 on success, negative return values indicate an internal |
| * error. |
| * UBI_NO_FASTMAP denotes that no fastmap was found. |
| * UBI_BAD_FASTMAP denotes that the found fastmap was invalid. |
| */ |
| static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info **ai) |
| { |
| int err, pnum, fm_anchor = -1; |
| unsigned long long max_sqnum = 0; |
| |
| err = -ENOMEM; |
| |
| ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| if (!ech) |
| goto out; |
| |
| vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
| if (!vidh) |
| goto out_ech; |
| |
| for (pnum = 0; pnum < UBI_FM_MAX_START; pnum++) { |
| int vol_id = -1; |
| unsigned long long sqnum = -1; |
| cond_resched(); |
| |
| dbg_gen("process PEB %d", pnum); |
| err = scan_peb(ubi, *ai, pnum, &vol_id, &sqnum); |
| if (err < 0) |
| goto out_vidh; |
| |
| if (vol_id == UBI_FM_SB_VOLUME_ID && sqnum > max_sqnum) { |
| max_sqnum = sqnum; |
| fm_anchor = pnum; |
| } |
| } |
| |
| ubi_free_vid_hdr(ubi, vidh); |
| kfree(ech); |
| |
| if (fm_anchor < 0) |
| return UBI_NO_FASTMAP; |
| |
| destroy_ai(*ai); |
| *ai = alloc_ai(); |
| if (!*ai) |
| return -ENOMEM; |
| |
| return ubi_scan_fastmap(ubi, *ai, fm_anchor); |
| |
| out_vidh: |
| ubi_free_vid_hdr(ubi, vidh); |
| out_ech: |
| kfree(ech); |
| out: |
| return err; |
| } |
| |
| #endif |
| |
| /** |
| * ubi_attach - attach an MTD device. |
| * @ubi: UBI device descriptor |
| * @force_scan: if set to non-zero attach by scanning |
| * |
| * This function returns zero in case of success and a negative error code in |
| * case of failure. |
| */ |
| int ubi_attach(struct ubi_device *ubi, int force_scan) |
| { |
| int err; |
| struct ubi_attach_info *ai; |
| |
| ai = alloc_ai(); |
| if (!ai) |
| return -ENOMEM; |
| |
| #ifdef CONFIG_MTD_UBI_FASTMAP |
| /* On small flash devices we disable fastmap in any case. */ |
| if ((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) { |
| ubi->fm_disabled = 1; |
| force_scan = 1; |
| } |
| |
| if (force_scan) |
| err = scan_all(ubi, ai, 0); |
| else { |
| err = scan_fast(ubi, &ai); |
| if (err > 0 || mtd_is_eccerr(err)) { |
| if (err != UBI_NO_FASTMAP) { |
| destroy_ai(ai); |
| ai = alloc_ai(); |
| if (!ai) |
| return -ENOMEM; |
| |
| err = scan_all(ubi, ai, 0); |
| } else { |
| err = scan_all(ubi, ai, UBI_FM_MAX_START); |
| } |
| } |
| } |
| #else |
| err = scan_all(ubi, ai, 0); |
| #endif |
| if (err) |
| goto out_ai; |
| |
| ubi->bad_peb_count = ai->bad_peb_count; |
| ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count; |
| ubi->corr_peb_count = ai->corr_peb_count; |
| ubi->max_ec = ai->max_ec; |
| ubi->mean_ec = ai->mean_ec; |
| dbg_gen("max. sequence number: %llu", ai->max_sqnum); |
| |
| err = ubi_read_volume_table(ubi, ai); |
| if (err) |
| goto out_ai; |
| |
| err = ubi_wl_init(ubi, ai); |
| if (err) |
| goto out_vtbl; |
| |
| err = ubi_eba_init(ubi, ai); |
| if (err) |
| goto out_wl; |
| |
| #ifdef CONFIG_MTD_UBI_FASTMAP |
| if (ubi->fm && ubi_dbg_chk_fastmap(ubi)) { |
| struct ubi_attach_info *scan_ai; |
| |
| scan_ai = alloc_ai(); |
| if (!scan_ai) { |
| err = -ENOMEM; |
| goto out_wl; |
| } |
| |
| err = scan_all(ubi, scan_ai, 0); |
| if (err) { |
| destroy_ai(scan_ai); |
| goto out_wl; |
| } |
| |
| err = self_check_eba(ubi, ai, scan_ai); |
| destroy_ai(scan_ai); |
| |
| if (err) |
| goto out_wl; |
| } |
| #endif |
| |
| destroy_ai(ai); |
| return 0; |
| |
| out_wl: |
| ubi_wl_close(ubi); |
| out_vtbl: |
| ubi_free_internal_volumes(ubi); |
| vfree(ubi->vtbl); |
| out_ai: |
| destroy_ai(ai); |
| return err; |
| } |
| |
| /** |
| * self_check_ai - check the attaching information. |
| * @ubi: UBI device description object |
| * @ai: attaching information |
| * |
| * This function returns zero if the attaching information is all right, and a |
| * negative error code if not or if an error occurred. |
| */ |
| static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai) |
| { |
| int pnum, err, vols_found = 0; |
| struct rb_node *rb1, *rb2; |
| struct ubi_ainf_volume *av; |
| struct ubi_ainf_peb *aeb, *last_aeb; |
| uint8_t *buf; |
| |
| if (!ubi_dbg_chk_gen(ubi)) |
| return 0; |
| |
| /* |
| * At first, check that attaching information is OK. |
| */ |
| ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
| int leb_count = 0; |
| |
| cond_resched(); |
| |
| vols_found += 1; |
| |
| if (ai->is_empty) { |
| ubi_err(ubi, "bad is_empty flag"); |
| goto bad_av; |
| } |
| |
| if (av->vol_id < 0 || av->highest_lnum < 0 || |
| av->leb_count < 0 || av->vol_type < 0 || av->used_ebs < 0 || |
| av->data_pad < 0 || av->last_data_size < 0) { |
| ubi_err(ubi, "negative values"); |
| goto bad_av; |
| } |
| |
| if (av->vol_id >= UBI_MAX_VOLUMES && |
| av->vol_id < UBI_INTERNAL_VOL_START) { |
| ubi_err(ubi, "bad vol_id"); |
| goto bad_av; |
| } |
| |
| if (av->vol_id > ai->highest_vol_id) { |
| ubi_err(ubi, "highest_vol_id is %d, but vol_id %d is there", |
| ai->highest_vol_id, av->vol_id); |
| goto out; |
| } |
| |
| if (av->vol_type != UBI_DYNAMIC_VOLUME && |
| av->vol_type != UBI_STATIC_VOLUME) { |
| ubi_err(ubi, "bad vol_type"); |
| goto bad_av; |
| } |
| |
| if (av->data_pad > ubi->leb_size / 2) { |
| ubi_err(ubi, "bad data_pad"); |
| goto bad_av; |
| } |
| |
| last_aeb = NULL; |
| ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { |
| cond_resched(); |
| |
| last_aeb = aeb; |
| leb_count += 1; |
| |
| if (aeb->pnum < 0 || aeb->ec < 0) { |
| ubi_err(ubi, "negative values"); |
| goto bad_aeb; |
| } |
| |
| if (aeb->ec < ai->min_ec) { |
| ubi_err(ubi, "bad ai->min_ec (%d), %d found", |
| ai->min_ec, aeb->ec); |
| goto bad_aeb; |
| } |
| |
| if (aeb->ec > ai->max_ec) { |
| ubi_err(ubi, "bad ai->max_ec (%d), %d found", |
| ai->max_ec, aeb->ec); |
| goto bad_aeb; |
| } |
| |
| if (aeb->pnum >= ubi->peb_count) { |
| ubi_err(ubi, "too high PEB number %d, total PEBs %d", |
| aeb->pnum, ubi->peb_count); |
| goto bad_aeb; |
| } |
| |
| if (av->vol_type == UBI_STATIC_VOLUME) { |
| if (aeb->lnum >= av->used_ebs) { |
| ubi_err(ubi, "bad lnum or used_ebs"); |
| goto bad_aeb; |
| } |
| } else { |
| if (av->used_ebs != 0) { |
| ubi_err(ubi, "non-zero used_ebs"); |
| goto bad_aeb; |
| } |
| } |
| |
| if (aeb->lnum > av->highest_lnum) { |
| ubi_err(ubi, "incorrect highest_lnum or lnum"); |
| goto bad_aeb; |
| } |
| } |
| |
| if (av->leb_count != leb_count) { |
| ubi_err(ubi, "bad leb_count, %d objects in the tree", |
| leb_count); |
| goto bad_av; |
| } |
| |
| if (!last_aeb) |
| continue; |
| |
| aeb = last_aeb; |
| |
| if (aeb->lnum != av->highest_lnum) { |
| ubi_err(ubi, "bad highest_lnum"); |
| goto bad_aeb; |
| } |
| } |
| |
| if (vols_found != ai->vols_found) { |
| ubi_err(ubi, "bad ai->vols_found %d, should be %d", |
| ai->vols_found, vols_found); |
| goto out; |
| } |
| |
| /* Check that attaching information is correct */ |
| ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
| last_aeb = NULL; |
| ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { |
| int vol_type; |
| |
| cond_resched(); |
| |
| last_aeb = aeb; |
| |
| err = ubi_io_read_vid_hdr(ubi, aeb->pnum, vidh, 1); |
| if (err && err != UBI_IO_BITFLIPS) { |
| ubi_err(ubi, "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 (av->vol_type != vol_type) { |
| ubi_err(ubi, "bad vol_type"); |
| goto bad_vid_hdr; |
| } |
| |
| if (aeb->sqnum != be64_to_cpu(vidh->sqnum)) { |
| ubi_err(ubi, "bad sqnum %llu", aeb->sqnum); |
| goto bad_vid_hdr; |
| } |
| |
| if (av->vol_id != be32_to_cpu(vidh->vol_id)) { |
| ubi_err(ubi, "bad vol_id %d", av->vol_id); |
| goto bad_vid_hdr; |
| } |
| |
| if (av->compat != vidh->compat) { |
| ubi_err(ubi, "bad compat %d", vidh->compat); |
| goto bad_vid_hdr; |
| } |
| |
| if (aeb->lnum != be32_to_cpu(vidh->lnum)) { |
| ubi_err(ubi, "bad lnum %d", aeb->lnum); |
| goto bad_vid_hdr; |
| } |
| |
| if (av->used_ebs != be32_to_cpu(vidh->used_ebs)) { |
| ubi_err(ubi, "bad used_ebs %d", av->used_ebs); |
| goto bad_vid_hdr; |
| } |
| |
| if (av->data_pad != be32_to_cpu(vidh->data_pad)) { |
| ubi_err(ubi, "bad data_pad %d", av->data_pad); |
| goto bad_vid_hdr; |
| } |
| } |
| |
| if (!last_aeb) |
| continue; |
| |
| if (av->highest_lnum != be32_to_cpu(vidh->lnum)) { |
| ubi_err(ubi, "bad highest_lnum %d", av->highest_lnum); |
| goto bad_vid_hdr; |
| } |
| |
| if (av->last_data_size != be32_to_cpu(vidh->data_size)) { |
| ubi_err(ubi, "bad last_data_size %d", |
| av->last_data_size); |
| goto bad_vid_hdr; |
| } |
| } |
| |
| /* |
| * Make sure that all the physical eraseblocks are in one of the lists |
| * or trees. |
| */ |
| buf = kzalloc(ubi->peb_count, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| 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] = 1; |
| } |
| |
| ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) |
| ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) |
| buf[aeb->pnum] = 1; |
| |
| list_for_each_entry(aeb, &ai->free, u.list) |
| buf[aeb->pnum] = 1; |
| |
| list_for_each_entry(aeb, &ai->corr, u.list) |
| buf[aeb->pnum] = 1; |
| |
| list_for_each_entry(aeb, &ai->erase, u.list) |
| buf[aeb->pnum] = 1; |
| |
| list_for_each_entry(aeb, &ai->alien, u.list) |
| buf[aeb->pnum] = 1; |
| |
| err = 0; |
| for (pnum = 0; pnum < ubi->peb_count; pnum++) |
| if (!buf[pnum]) { |
| ubi_err(ubi, "PEB %d is not referred", pnum); |
| err = 1; |
| } |
| |
| kfree(buf); |
| if (err) |
| goto out; |
| return 0; |
| |
| bad_aeb: |
| ubi_err(ubi, "bad attaching information about LEB %d", aeb->lnum); |
| ubi_dump_aeb(aeb, 0); |
| ubi_dump_av(av); |
| goto out; |
| |
| bad_av: |
| ubi_err(ubi, "bad attaching information about volume %d", av->vol_id); |
| ubi_dump_av(av); |
| goto out; |
| |
| bad_vid_hdr: |
| ubi_err(ubi, "bad attaching information about volume %d", av->vol_id); |
| ubi_dump_av(av); |
| ubi_dump_vid_hdr(vidh); |
| |
| out: |
| dump_stack(); |
| return -EINVAL; |
| } |