123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809 |
- /*
- * This file is part of UBIFS.
- *
- * Copyright (C) 2006-2008 Nokia Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * 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., 51
- * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * Authors: Artem Bityutskiy (Битюцкий Артём)
- * Adrian Hunter
- */
- /*
- * This file implements UBIFS superblock. The superblock is stored at the first
- * LEB of the volume and is never changed by UBIFS. Only user-space tools may
- * change it. The superblock node mostly contains geometry information.
- */
- #include "ubifs.h"
- #include <linux/slab.h>
- #include <linux/random.h>
- #include <linux/math64.h>
- /*
- * Default journal size in logical eraseblocks as a percent of total
- * flash size.
- */
- #define DEFAULT_JNL_PERCENT 5
- /* Default maximum journal size in bytes */
- #define DEFAULT_MAX_JNL (32*1024*1024)
- /* Default indexing tree fanout */
- #define DEFAULT_FANOUT 8
- /* Default number of data journal heads */
- #define DEFAULT_JHEADS_CNT 1
- /* Default positions of different LEBs in the main area */
- #define DEFAULT_IDX_LEB 0
- #define DEFAULT_DATA_LEB 1
- #define DEFAULT_GC_LEB 2
- /* Default number of LEB numbers in LPT's save table */
- #define DEFAULT_LSAVE_CNT 256
- /* Default reserved pool size as a percent of maximum free space */
- #define DEFAULT_RP_PERCENT 5
- /* The default maximum size of reserved pool in bytes */
- #define DEFAULT_MAX_RP_SIZE (5*1024*1024)
- /* Default time granularity in nanoseconds */
- #define DEFAULT_TIME_GRAN 1000000000
- /**
- * create_default_filesystem - format empty UBI volume.
- * @c: UBIFS file-system description object
- *
- * This function creates default empty file-system. Returns zero in case of
- * success and a negative error code in case of failure.
- */
- static int create_default_filesystem(struct ubifs_info *c)
- {
- struct ubifs_sb_node *sup;
- struct ubifs_mst_node *mst;
- struct ubifs_idx_node *idx;
- struct ubifs_branch *br;
- struct ubifs_ino_node *ino;
- struct ubifs_cs_node *cs;
- union ubifs_key key;
- int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first;
- int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0;
- int min_leb_cnt = UBIFS_MIN_LEB_CNT;
- long long tmp64, main_bytes;
- __le64 tmp_le64;
- /* Some functions called from here depend on the @c->key_len filed */
- c->key_len = UBIFS_SK_LEN;
- /*
- * First of all, we have to calculate default file-system geometry -
- * log size, journal size, etc.
- */
- if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT)
- /* We can first multiply then divide and have no overflow */
- jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100;
- else
- jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT;
- if (jnl_lebs < UBIFS_MIN_JNL_LEBS)
- jnl_lebs = UBIFS_MIN_JNL_LEBS;
- if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL)
- jnl_lebs = DEFAULT_MAX_JNL / c->leb_size;
- /*
- * The log should be large enough to fit reference nodes for all bud
- * LEBs. Because buds do not have to start from the beginning of LEBs
- * (half of the LEB may contain committed data), the log should
- * generally be larger, make it twice as large.
- */
- tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1;
- log_lebs = tmp / c->leb_size;
- /* Plus one LEB reserved for commit */
- log_lebs += 1;
- if (c->leb_cnt - min_leb_cnt > 8) {
- /* And some extra space to allow writes while committing */
- log_lebs += 1;
- min_leb_cnt += 1;
- }
- max_buds = jnl_lebs - log_lebs;
- if (max_buds < UBIFS_MIN_BUD_LEBS)
- max_buds = UBIFS_MIN_BUD_LEBS;
- /*
- * Orphan nodes are stored in a separate area. One node can store a lot
- * of orphan inode numbers, but when new orphan comes we just add a new
- * orphan node. At some point the nodes are consolidated into one
- * orphan node.
- */
- orph_lebs = UBIFS_MIN_ORPH_LEBS;
- if (c->leb_cnt - min_leb_cnt > 1)
- /*
- * For debugging purposes it is better to have at least 2
- * orphan LEBs, because the orphan subsystem would need to do
- * consolidations and would be stressed more.
- */
- orph_lebs += 1;
- main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs;
- main_lebs -= orph_lebs;
- lpt_first = UBIFS_LOG_LNUM + log_lebs;
- c->lsave_cnt = DEFAULT_LSAVE_CNT;
- c->max_leb_cnt = c->leb_cnt;
- err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs,
- &big_lpt);
- if (err)
- return err;
- dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first,
- lpt_first + lpt_lebs - 1);
- main_first = c->leb_cnt - main_lebs;
- /* Create default superblock */
- tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
- sup = kzalloc(tmp, GFP_KERNEL);
- if (!sup)
- return -ENOMEM;
- tmp64 = (long long)max_buds * c->leb_size;
- if (big_lpt)
- sup_flags |= UBIFS_FLG_BIGLPT;
- sup->ch.node_type = UBIFS_SB_NODE;
- sup->key_hash = UBIFS_KEY_HASH_R5;
- sup->flags = cpu_to_le32(sup_flags);
- sup->min_io_size = cpu_to_le32(c->min_io_size);
- sup->leb_size = cpu_to_le32(c->leb_size);
- sup->leb_cnt = cpu_to_le32(c->leb_cnt);
- sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt);
- sup->max_bud_bytes = cpu_to_le64(tmp64);
- sup->log_lebs = cpu_to_le32(log_lebs);
- sup->lpt_lebs = cpu_to_le32(lpt_lebs);
- sup->orph_lebs = cpu_to_le32(orph_lebs);
- sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT);
- sup->fanout = cpu_to_le32(DEFAULT_FANOUT);
- sup->lsave_cnt = cpu_to_le32(c->lsave_cnt);
- sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION);
- sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN);
- if (c->mount_opts.override_compr)
- sup->default_compr = cpu_to_le16(c->mount_opts.compr_type);
- else
- sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
- generate_random_uuid(sup->uuid);
- main_bytes = (long long)main_lebs * c->leb_size;
- tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100);
- if (tmp64 > DEFAULT_MAX_RP_SIZE)
- tmp64 = DEFAULT_MAX_RP_SIZE;
- sup->rp_size = cpu_to_le64(tmp64);
- sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION);
- err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0);
- kfree(sup);
- if (err)
- return err;
- dbg_gen("default superblock created at LEB 0:0");
- /* Create default master node */
- mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
- if (!mst)
- return -ENOMEM;
- mst->ch.node_type = UBIFS_MST_NODE;
- mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM);
- mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO);
- mst->cmt_no = 0;
- mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
- mst->root_offs = 0;
- tmp = ubifs_idx_node_sz(c, 1);
- mst->root_len = cpu_to_le32(tmp);
- mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB);
- mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
- mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size));
- mst->index_size = cpu_to_le64(ALIGN(tmp, 8));
- mst->lpt_lnum = cpu_to_le32(c->lpt_lnum);
- mst->lpt_offs = cpu_to_le32(c->lpt_offs);
- mst->nhead_lnum = cpu_to_le32(c->nhead_lnum);
- mst->nhead_offs = cpu_to_le32(c->nhead_offs);
- mst->ltab_lnum = cpu_to_le32(c->ltab_lnum);
- mst->ltab_offs = cpu_to_le32(c->ltab_offs);
- mst->lsave_lnum = cpu_to_le32(c->lsave_lnum);
- mst->lsave_offs = cpu_to_le32(c->lsave_offs);
- mst->lscan_lnum = cpu_to_le32(main_first);
- mst->empty_lebs = cpu_to_le32(main_lebs - 2);
- mst->idx_lebs = cpu_to_le32(1);
- mst->leb_cnt = cpu_to_le32(c->leb_cnt);
- /* Calculate lprops statistics */
- tmp64 = main_bytes;
- tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
- tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
- mst->total_free = cpu_to_le64(tmp64);
- tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
- ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) -
- UBIFS_INO_NODE_SZ;
- tmp64 += ino_waste;
- tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8);
- mst->total_dirty = cpu_to_le64(tmp64);
- /* The indexing LEB does not contribute to dark space */
- tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm);
- mst->total_dark = cpu_to_le64(tmp64);
- mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ);
- err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0);
- if (err) {
- kfree(mst);
- return err;
- }
- err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1,
- 0);
- kfree(mst);
- if (err)
- return err;
- dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM);
- /* Create the root indexing node */
- tmp = ubifs_idx_node_sz(c, 1);
- idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
- if (!idx)
- return -ENOMEM;
- c->key_fmt = UBIFS_SIMPLE_KEY_FMT;
- c->key_hash = key_r5_hash;
- idx->ch.node_type = UBIFS_IDX_NODE;
- idx->child_cnt = cpu_to_le16(1);
- ino_key_init(c, &key, UBIFS_ROOT_INO);
- br = ubifs_idx_branch(c, idx, 0);
- key_write_idx(c, &key, &br->key);
- br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB);
- br->len = cpu_to_le32(UBIFS_INO_NODE_SZ);
- err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0);
- kfree(idx);
- if (err)
- return err;
- dbg_gen("default root indexing node created LEB %d:0",
- main_first + DEFAULT_IDX_LEB);
- /* Create default root inode */
- tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
- ino = kzalloc(tmp, GFP_KERNEL);
- if (!ino)
- return -ENOMEM;
- ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO);
- ino->ch.node_type = UBIFS_INO_NODE;
- ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
- ino->nlink = cpu_to_le32(2);
- tmp_le64 = cpu_to_le64(CURRENT_TIME_SEC.tv_sec);
- ino->atime_sec = tmp_le64;
- ino->ctime_sec = tmp_le64;
- ino->mtime_sec = tmp_le64;
- ino->atime_nsec = 0;
- ino->ctime_nsec = 0;
- ino->mtime_nsec = 0;
- ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
- ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);
- /* Set compression enabled by default */
- ino->flags = cpu_to_le32(UBIFS_COMPR_FL);
- err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
- main_first + DEFAULT_DATA_LEB, 0);
- kfree(ino);
- if (err)
- return err;
- dbg_gen("root inode created at LEB %d:0",
- main_first + DEFAULT_DATA_LEB);
- /*
- * The first node in the log has to be the commit start node. This is
- * always the case during normal file-system operation. Write a fake
- * commit start node to the log.
- */
- tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size);
- cs = kzalloc(tmp, GFP_KERNEL);
- if (!cs)
- return -ENOMEM;
- cs->ch.node_type = UBIFS_CS_NODE;
- err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, 0);
- kfree(cs);
- if (err)
- return err;
- ubifs_msg(c, "default file-system created");
- return 0;
- }
- /**
- * validate_sb - validate superblock node.
- * @c: UBIFS file-system description object
- * @sup: superblock node
- *
- * This function validates superblock node @sup. Since most of data was read
- * from the superblock and stored in @c, the function validates fields in @c
- * instead. Returns zero in case of success and %-EINVAL in case of validation
- * failure.
- */
- static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
- {
- long long max_bytes;
- int err = 1, min_leb_cnt;
- if (!c->key_hash) {
- err = 2;
- goto failed;
- }
- if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) {
- err = 3;
- goto failed;
- }
- if (le32_to_cpu(sup->min_io_size) != c->min_io_size) {
- ubifs_err(c, "min. I/O unit mismatch: %d in superblock, %d real",
- le32_to_cpu(sup->min_io_size), c->min_io_size);
- goto failed;
- }
- if (le32_to_cpu(sup->leb_size) != c->leb_size) {
- ubifs_err(c, "LEB size mismatch: %d in superblock, %d real",
- le32_to_cpu(sup->leb_size), c->leb_size);
- goto failed;
- }
- if (c->log_lebs < UBIFS_MIN_LOG_LEBS ||
- c->lpt_lebs < UBIFS_MIN_LPT_LEBS ||
- c->orph_lebs < UBIFS_MIN_ORPH_LEBS ||
- c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
- err = 4;
- goto failed;
- }
- /*
- * Calculate minimum allowed amount of main area LEBs. This is very
- * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
- * have just read from the superblock.
- */
- min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs;
- min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6;
- if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) {
- ubifs_err(c, "bad LEB count: %d in superblock, %d on UBI volume, %d minimum required",
- c->leb_cnt, c->vi.size, min_leb_cnt);
- goto failed;
- }
- if (c->max_leb_cnt < c->leb_cnt) {
- ubifs_err(c, "max. LEB count %d less than LEB count %d",
- c->max_leb_cnt, c->leb_cnt);
- goto failed;
- }
- if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
- ubifs_err(c, "too few main LEBs count %d, must be at least %d",
- c->main_lebs, UBIFS_MIN_MAIN_LEBS);
- goto failed;
- }
- max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS;
- if (c->max_bud_bytes < max_bytes) {
- ubifs_err(c, "too small journal (%lld bytes), must be at least %lld bytes",
- c->max_bud_bytes, max_bytes);
- goto failed;
- }
- max_bytes = (long long)c->leb_size * c->main_lebs;
- if (c->max_bud_bytes > max_bytes) {
- ubifs_err(c, "too large journal size (%lld bytes), only %lld bytes available in the main area",
- c->max_bud_bytes, max_bytes);
- goto failed;
- }
- if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 ||
- c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) {
- err = 9;
- goto failed;
- }
- if (c->fanout < UBIFS_MIN_FANOUT ||
- ubifs_idx_node_sz(c, c->fanout) > c->leb_size) {
- err = 10;
- goto failed;
- }
- if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT &&
- c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS -
- c->log_lebs - c->lpt_lebs - c->orph_lebs)) {
- err = 11;
- goto failed;
- }
- if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs +
- c->orph_lebs + c->main_lebs != c->leb_cnt) {
- err = 12;
- goto failed;
- }
- if (c->default_compr >= UBIFS_COMPR_TYPES_CNT) {
- err = 13;
- goto failed;
- }
- if (c->rp_size < 0 || max_bytes < c->rp_size) {
- err = 14;
- goto failed;
- }
- if (le32_to_cpu(sup->time_gran) > 1000000000 ||
- le32_to_cpu(sup->time_gran) < 1) {
- err = 15;
- goto failed;
- }
- return 0;
- failed:
- ubifs_err(c, "bad superblock, error %d", err);
- ubifs_dump_node(c, sup);
- return -EINVAL;
- }
- /**
- * ubifs_read_sb_node - read superblock node.
- * @c: UBIFS file-system description object
- *
- * This function returns a pointer to the superblock node or a negative error
- * code. Note, the user of this function is responsible of kfree()'ing the
- * returned superblock buffer.
- */
- struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c)
- {
- struct ubifs_sb_node *sup;
- int err;
- sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS);
- if (!sup)
- return ERR_PTR(-ENOMEM);
- err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ,
- UBIFS_SB_LNUM, 0);
- if (err) {
- kfree(sup);
- return ERR_PTR(err);
- }
- return sup;
- }
- /**
- * ubifs_write_sb_node - write superblock node.
- * @c: UBIFS file-system description object
- * @sup: superblock node read with 'ubifs_read_sb_node()'
- *
- * This function returns %0 on success and a negative error code on failure.
- */
- int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup)
- {
- int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
- ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1);
- return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len);
- }
- /**
- * ubifs_read_superblock - read superblock.
- * @c: UBIFS file-system description object
- *
- * This function finds, reads and checks the superblock. If an empty UBI volume
- * is being mounted, this function creates default superblock. Returns zero in
- * case of success, and a negative error code in case of failure.
- */
- int ubifs_read_superblock(struct ubifs_info *c)
- {
- int err, sup_flags;
- struct ubifs_sb_node *sup;
- if (c->empty) {
- err = create_default_filesystem(c);
- if (err)
- return err;
- }
- sup = ubifs_read_sb_node(c);
- if (IS_ERR(sup))
- return PTR_ERR(sup);
- c->fmt_version = le32_to_cpu(sup->fmt_version);
- c->ro_compat_version = le32_to_cpu(sup->ro_compat_version);
- /*
- * The software supports all previous versions but not future versions,
- * due to the unavailability of time-travelling equipment.
- */
- if (c->fmt_version > UBIFS_FORMAT_VERSION) {
- ubifs_assert(!c->ro_media || c->ro_mount);
- if (!c->ro_mount ||
- c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) {
- ubifs_err(c, "on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d",
- c->fmt_version, c->ro_compat_version,
- UBIFS_FORMAT_VERSION,
- UBIFS_RO_COMPAT_VERSION);
- if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) {
- ubifs_msg(c, "only R/O mounting is possible");
- err = -EROFS;
- } else
- err = -EINVAL;
- goto out;
- }
- /*
- * The FS is mounted R/O, and the media format is
- * R/O-compatible with the UBIFS implementation, so we can
- * mount.
- */
- c->rw_incompat = 1;
- }
- if (c->fmt_version < 3) {
- ubifs_err(c, "on-flash format version %d is not supported",
- c->fmt_version);
- err = -EINVAL;
- goto out;
- }
- switch (sup->key_hash) {
- case UBIFS_KEY_HASH_R5:
- c->key_hash = key_r5_hash;
- c->key_hash_type = UBIFS_KEY_HASH_R5;
- break;
- case UBIFS_KEY_HASH_TEST:
- c->key_hash = key_test_hash;
- c->key_hash_type = UBIFS_KEY_HASH_TEST;
- break;
- };
- c->key_fmt = sup->key_fmt;
- switch (c->key_fmt) {
- case UBIFS_SIMPLE_KEY_FMT:
- c->key_len = UBIFS_SK_LEN;
- break;
- default:
- ubifs_err(c, "unsupported key format");
- err = -EINVAL;
- goto out;
- }
- c->leb_cnt = le32_to_cpu(sup->leb_cnt);
- c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt);
- c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes);
- c->log_lebs = le32_to_cpu(sup->log_lebs);
- c->lpt_lebs = le32_to_cpu(sup->lpt_lebs);
- c->orph_lebs = le32_to_cpu(sup->orph_lebs);
- c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
- c->fanout = le32_to_cpu(sup->fanout);
- c->lsave_cnt = le32_to_cpu(sup->lsave_cnt);
- c->rp_size = le64_to_cpu(sup->rp_size);
- c->rp_uid = make_kuid(&init_user_ns, le32_to_cpu(sup->rp_uid));
- c->rp_gid = make_kgid(&init_user_ns, le32_to_cpu(sup->rp_gid));
- sup_flags = le32_to_cpu(sup->flags);
- if (!c->mount_opts.override_compr)
- c->default_compr = le16_to_cpu(sup->default_compr);
- c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
- memcpy(&c->uuid, &sup->uuid, 16);
- c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
- c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP);
- /* Automatically increase file system size to the maximum size */
- c->old_leb_cnt = c->leb_cnt;
- if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) {
- c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size);
- if (c->ro_mount)
- dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs",
- c->old_leb_cnt, c->leb_cnt);
- else {
- dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs",
- c->old_leb_cnt, c->leb_cnt);
- sup->leb_cnt = cpu_to_le32(c->leb_cnt);
- err = ubifs_write_sb_node(c, sup);
- if (err)
- goto out;
- c->old_leb_cnt = c->leb_cnt;
- }
- }
- c->log_bytes = (long long)c->log_lebs * c->leb_size;
- c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1;
- c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs;
- c->lpt_last = c->lpt_first + c->lpt_lebs - 1;
- c->orph_first = c->lpt_last + 1;
- c->orph_last = c->orph_first + c->orph_lebs - 1;
- c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS;
- c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs;
- c->main_first = c->leb_cnt - c->main_lebs;
- err = validate_sb(c, sup);
- out:
- kfree(sup);
- return err;
- }
- /**
- * fixup_leb - fixup/unmap an LEB containing free space.
- * @c: UBIFS file-system description object
- * @lnum: the LEB number to fix up
- * @len: number of used bytes in LEB (starting at offset 0)
- *
- * This function reads the contents of the given LEB number @lnum, then fixes
- * it up, so that empty min. I/O units in the end of LEB are actually erased on
- * flash (rather than being just all-0xff real data). If the LEB is completely
- * empty, it is simply unmapped.
- */
- static int fixup_leb(struct ubifs_info *c, int lnum, int len)
- {
- int err;
- ubifs_assert(len >= 0);
- ubifs_assert(len % c->min_io_size == 0);
- ubifs_assert(len < c->leb_size);
- if (len == 0) {
- dbg_mnt("unmap empty LEB %d", lnum);
- return ubifs_leb_unmap(c, lnum);
- }
- dbg_mnt("fixup LEB %d, data len %d", lnum, len);
- err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1);
- if (err)
- return err;
- return ubifs_leb_change(c, lnum, c->sbuf, len);
- }
- /**
- * fixup_free_space - find & remap all LEBs containing free space.
- * @c: UBIFS file-system description object
- *
- * This function walks through all LEBs in the filesystem and fiexes up those
- * containing free/empty space.
- */
- static int fixup_free_space(struct ubifs_info *c)
- {
- int lnum, err = 0;
- struct ubifs_lprops *lprops;
- ubifs_get_lprops(c);
- /* Fixup LEBs in the master area */
- for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) {
- err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz);
- if (err)
- goto out;
- }
- /* Unmap unused log LEBs */
- lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
- while (lnum != c->ltail_lnum) {
- err = fixup_leb(c, lnum, 0);
- if (err)
- goto out;
- lnum = ubifs_next_log_lnum(c, lnum);
- }
- /*
- * Fixup the log head which contains the only a CS node at the
- * beginning.
- */
- err = fixup_leb(c, c->lhead_lnum,
- ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size));
- if (err)
- goto out;
- /* Fixup LEBs in the LPT area */
- for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
- int free = c->ltab[lnum - c->lpt_first].free;
- if (free > 0) {
- err = fixup_leb(c, lnum, c->leb_size - free);
- if (err)
- goto out;
- }
- }
- /* Unmap LEBs in the orphans area */
- for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
- err = fixup_leb(c, lnum, 0);
- if (err)
- goto out;
- }
- /* Fixup LEBs in the main area */
- for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) {
- lprops = ubifs_lpt_lookup(c, lnum);
- if (IS_ERR(lprops)) {
- err = PTR_ERR(lprops);
- goto out;
- }
- if (lprops->free > 0) {
- err = fixup_leb(c, lnum, c->leb_size - lprops->free);
- if (err)
- goto out;
- }
- }
- out:
- ubifs_release_lprops(c);
- return err;
- }
- /**
- * ubifs_fixup_free_space - find & fix all LEBs with free space.
- * @c: UBIFS file-system description object
- *
- * This function fixes up LEBs containing free space on first mount, if the
- * appropriate flag was set when the FS was created. Each LEB with one or more
- * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure
- * the free space is actually erased. E.g., this is necessary for some NAND
- * chips, since the free space may have been programmed like real "0xff" data
- * (generating a non-0xff ECC), causing future writes to the not-really-erased
- * NAND pages to behave badly. After the space is fixed up, the superblock flag
- * is cleared, so that this is skipped for all future mounts.
- */
- int ubifs_fixup_free_space(struct ubifs_info *c)
- {
- int err;
- struct ubifs_sb_node *sup;
- ubifs_assert(c->space_fixup);
- ubifs_assert(!c->ro_mount);
- ubifs_msg(c, "start fixing up free space");
- err = fixup_free_space(c);
- if (err)
- return err;
- sup = ubifs_read_sb_node(c);
- if (IS_ERR(sup))
- return PTR_ERR(sup);
- /* Free-space fixup is no longer required */
- c->space_fixup = 0;
- sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP);
- err = ubifs_write_sb_node(c, sup);
- kfree(sup);
- if (err)
- return err;
- ubifs_msg(c, "free space fixup complete");
- return err;
- }
|