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author | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2008-07-14 16:08:37 (GMT) |
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committer | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2008-07-15 14:35:15 (GMT) |
commit | 1e51764a3c2ac05a23a22b2a95ddee4d9bffb16d (patch) | |
tree | 919debdd48aef9eee9ff0e8f465ef2649325b993 /fs/ubifs/master.c | |
parent | e56a99d5a42dcb91e622ae7a0289d8fb2ddabffb (diff) | |
download | linux-1e51764a3c2ac05a23a22b2a95ddee4d9bffb16d.tar.xz |
UBIFS: add new flash file system
This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Diffstat (limited to 'fs/ubifs/master.c')
-rw-r--r-- | fs/ubifs/master.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c new file mode 100644 index 0000000..71d5493 --- /dev/null +++ b/fs/ubifs/master.c @@ -0,0 +1,387 @@ +/* + * 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 reading and writing the master node */ + +#include "ubifs.h" + +/** + * scan_for_master - search the valid master node. + * @c: UBIFS file-system description object + * + * This function scans the master node LEBs and search for the latest master + * node. Returns zero in case of success and a negative error code in case of + * failure. + */ +static int scan_for_master(struct ubifs_info *c) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + int lnum, offs = 0, nodes_cnt; + + lnum = UBIFS_MST_LNUM; + + sleb = ubifs_scan(c, lnum, 0, c->sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + nodes_cnt = sleb->nodes_cnt; + if (nodes_cnt > 0) { + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, + list); + if (snod->type != UBIFS_MST_NODE) + goto out; + memcpy(c->mst_node, snod->node, snod->len); + offs = snod->offs; + } + ubifs_scan_destroy(sleb); + + lnum += 1; + + sleb = ubifs_scan(c, lnum, 0, c->sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + if (sleb->nodes_cnt != nodes_cnt) + goto out; + if (!sleb->nodes_cnt) + goto out; + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list); + if (snod->type != UBIFS_MST_NODE) + goto out; + if (snod->offs != offs) + goto out; + if (memcmp((void *)c->mst_node + UBIFS_CH_SZ, + (void *)snod->node + UBIFS_CH_SZ, + UBIFS_MST_NODE_SZ - UBIFS_CH_SZ)) + goto out; + c->mst_offs = offs; + ubifs_scan_destroy(sleb); + return 0; + +out: + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * validate_master - validate master node. + * @c: UBIFS file-system description object + * + * This function validates data which was read from master node. Returns zero + * if the data is all right and %-EINVAL if not. + */ +static int validate_master(const struct ubifs_info *c) +{ + long long main_sz; + int err; + + if (c->max_sqnum >= SQNUM_WATERMARK) { + err = 1; + goto out; + } + + if (c->cmt_no >= c->max_sqnum) { + err = 2; + goto out; + } + + if (c->highest_inum >= INUM_WATERMARK) { + err = 3; + goto out; + } + + if (c->lhead_lnum < UBIFS_LOG_LNUM || + c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs || + c->lhead_offs < 0 || c->lhead_offs >= c->leb_size || + c->lhead_offs & (c->min_io_size - 1)) { + err = 4; + goto out; + } + + if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first || + c->zroot.offs >= c->leb_size || c->zroot.offs & 7) { + err = 5; + goto out; + } + + if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len || + c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) { + err = 6; + goto out; + } + + if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) { + err = 7; + goto out; + } + + if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first || + c->ihead_offs % c->min_io_size || c->ihead_offs < 0 || + c->ihead_offs > c->leb_size || c->ihead_offs & 7) { + err = 8; + goto out; + } + + main_sz = (long long)c->main_lebs * c->leb_size; + if (c->old_idx_sz & 7 || c->old_idx_sz >= main_sz) { + err = 9; + goto out; + } + + if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last || + c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) { + err = 10; + goto out; + } + + if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last || + c->nhead_offs < 0 || c->nhead_offs % c->min_io_size || + c->nhead_offs > c->leb_size) { + err = 11; + goto out; + } + + if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last || + c->ltab_offs < 0 || + c->ltab_offs + c->ltab_sz > c->leb_size) { + err = 12; + goto out; + } + + if (c->big_lpt && (c->lsave_lnum < c->lpt_first || + c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 || + c->lsave_offs + c->lsave_sz > c->leb_size)) { + err = 13; + goto out; + } + + if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) { + err = 14; + goto out; + } + + if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) { + err = 15; + goto out; + } + + if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) { + err = 16; + goto out; + } + + if (c->lst.total_free < 0 || c->lst.total_free > main_sz || + c->lst.total_free & 7) { + err = 17; + goto out; + } + + if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) { + err = 18; + goto out; + } + + if (c->lst.total_used < 0 || (c->lst.total_used & 7)) { + err = 19; + goto out; + } + + if (c->lst.total_free + c->lst.total_dirty + + c->lst.total_used > main_sz) { + err = 20; + goto out; + } + + if (c->lst.total_dead + c->lst.total_dark + + c->lst.total_used + c->old_idx_sz > main_sz) { + err = 21; + goto out; + } + + if (c->lst.total_dead < 0 || + c->lst.total_dead > c->lst.total_free + c->lst.total_dirty || + c->lst.total_dead & 7) { + err = 22; + goto out; + } + + if (c->lst.total_dark < 0 || + c->lst.total_dark > c->lst.total_free + c->lst.total_dirty || + c->lst.total_dark & 7) { + err = 23; + goto out; + } + + return 0; + +out: + ubifs_err("bad master node at offset %d error %d", c->mst_offs, err); + dbg_dump_node(c, c->mst_node); + return -EINVAL; +} + +/** + * ubifs_read_master - read master node. + * @c: UBIFS file-system description object + * + * This function finds and reads the master node during file-system mount. If + * the flash is empty, it creates default master node as well. Returns zero in + * case of success and a negative error code in case of failure. + */ +int ubifs_read_master(struct ubifs_info *c) +{ + int err, old_leb_cnt; + + c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL); + if (!c->mst_node) + return -ENOMEM; + + err = scan_for_master(c); + if (err) { + err = ubifs_recover_master_node(c); + if (err) + /* + * Note, we do not free 'c->mst_node' here because the + * unmount routine will take care of this. + */ + return err; + } + + /* Make sure that the recovery flag is clear */ + c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY); + + c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum); + c->highest_inum = le64_to_cpu(c->mst_node->highest_inum); + c->cmt_no = le64_to_cpu(c->mst_node->cmt_no); + c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum); + c->zroot.offs = le32_to_cpu(c->mst_node->root_offs); + c->zroot.len = le32_to_cpu(c->mst_node->root_len); + c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum); + c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum); + c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum); + c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs); + c->old_idx_sz = le64_to_cpu(c->mst_node->index_size); + c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum); + c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs); + c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum); + c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs); + c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum); + c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs); + c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum); + c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs); + c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum); + c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs); + c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs); + old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt); + c->lst.total_free = le64_to_cpu(c->mst_node->total_free); + c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty); + c->lst.total_used = le64_to_cpu(c->mst_node->total_used); + c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead); + c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark); + + c->calc_idx_sz = c->old_idx_sz; + + if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS)) + c->no_orphs = 1; + + if (old_leb_cnt != c->leb_cnt) { + /* The file system has been resized */ + int growth = c->leb_cnt - old_leb_cnt; + + if (c->leb_cnt < old_leb_cnt || + c->leb_cnt < UBIFS_MIN_LEB_CNT) { + ubifs_err("bad leb_cnt on master node"); + dbg_dump_node(c, c->mst_node); + return -EINVAL; + } + + dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs", + old_leb_cnt, c->leb_cnt); + c->lst.empty_lebs += growth; + c->lst.total_free += growth * (long long)c->leb_size; + c->lst.total_dark += growth * (long long)c->dark_wm; + + /* + * Reflect changes back onto the master node. N.B. the master + * node gets written immediately whenever mounting (or + * remounting) in read-write mode, so we do not need to write it + * here. + */ + c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt); + c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs); + c->mst_node->total_free = cpu_to_le64(c->lst.total_free); + c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark); + } + + err = validate_master(c); + if (err) + return err; + + err = dbg_old_index_check_init(c, &c->zroot); + + return err; +} + +/** + * ubifs_write_master - write master node. + * @c: UBIFS file-system description object + * + * This function writes the master node. The caller has to take the + * @c->mst_mutex lock before calling this function. Returns zero in case of + * success and a negative error code in case of failure. The master node is + * written twice to enable recovery. + */ +int ubifs_write_master(struct ubifs_info *c) +{ + int err, lnum, offs, len; + + if (c->ro_media) + return -EINVAL; + + lnum = UBIFS_MST_LNUM; + offs = c->mst_offs + c->mst_node_alsz; + len = UBIFS_MST_NODE_SZ; + + if (offs + UBIFS_MST_NODE_SZ > c->leb_size) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + offs = 0; + } + + c->mst_offs = offs; + c->mst_node->highest_inum = cpu_to_le64(c->highest_inum); + + err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM); + if (err) + return err; + + lnum += 1; + + if (offs == 0) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM); + + return err; +} |