2 * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 * Authors: Artem Bityutskiy (Битюцкий Артём)
23 /* This file implements reading and writing the master node */
28 * scan_for_master - search the valid master node.
29 * @c: UBIFS file-system description object
31 * This function scans the master node LEBs and search for the latest master
32 * node. Returns zero in case of success and a negative error code in case of
35 static int scan_for_master(struct ubifs_info *c)
37 struct ubifs_scan_leb *sleb;
38 struct ubifs_scan_node *snod;
39 int lnum, offs = 0, nodes_cnt;
41 lnum = UBIFS_MST_LNUM;
43 sleb = ubifs_scan(c, lnum, 0, c->sbuf);
46 nodes_cnt = sleb->nodes_cnt;
48 snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
50 if (snod->type != UBIFS_MST_NODE)
52 memcpy(c->mst_node, snod->node, snod->len);
55 ubifs_scan_destroy(sleb);
59 sleb = ubifs_scan(c, lnum, 0, c->sbuf);
62 if (sleb->nodes_cnt != nodes_cnt)
66 snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list);
67 if (snod->type != UBIFS_MST_NODE)
69 if (snod->offs != offs)
71 if (memcmp((void *)c->mst_node + UBIFS_CH_SZ,
72 (void *)snod->node + UBIFS_CH_SZ,
73 UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
76 ubifs_scan_destroy(sleb);
80 ubifs_scan_destroy(sleb);
85 * validate_master - validate master node.
86 * @c: UBIFS file-system description object
88 * This function validates data which was read from master node. Returns zero
89 * if the data is all right and %-EINVAL if not.
91 static int validate_master(const struct ubifs_info *c)
96 if (c->max_sqnum >= SQNUM_WATERMARK) {
101 if (c->cmt_no >= c->max_sqnum) {
106 if (c->highest_inum >= INUM_WATERMARK) {
111 if (c->lhead_lnum < UBIFS_LOG_LNUM ||
112 c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs ||
113 c->lhead_offs < 0 || c->lhead_offs >= c->leb_size ||
114 c->lhead_offs & (c->min_io_size - 1)) {
119 if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first ||
120 c->zroot.offs >= c->leb_size || c->zroot.offs & 7) {
125 if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len ||
126 c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) {
131 if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) {
136 if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first ||
137 c->ihead_offs % c->min_io_size || c->ihead_offs < 0 ||
138 c->ihead_offs > c->leb_size || c->ihead_offs & 7) {
143 main_sz = (long long)c->main_lebs * c->leb_size;
144 if (c->old_idx_sz & 7 || c->old_idx_sz >= main_sz) {
149 if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last ||
150 c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) {
155 if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last ||
156 c->nhead_offs < 0 || c->nhead_offs % c->min_io_size ||
157 c->nhead_offs > c->leb_size) {
162 if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last ||
164 c->ltab_offs + c->ltab_sz > c->leb_size) {
169 if (c->big_lpt && (c->lsave_lnum < c->lpt_first ||
170 c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 ||
171 c->lsave_offs + c->lsave_sz > c->leb_size)) {
176 if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) {
181 if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) {
186 if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) {
191 if (c->lst.total_free < 0 || c->lst.total_free > main_sz ||
192 c->lst.total_free & 7) {
197 if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) {
202 if (c->lst.total_used < 0 || (c->lst.total_used & 7)) {
207 if (c->lst.total_free + c->lst.total_dirty +
208 c->lst.total_used > main_sz) {
213 if (c->lst.total_dead + c->lst.total_dark +
214 c->lst.total_used + c->old_idx_sz > main_sz) {
219 if (c->lst.total_dead < 0 ||
220 c->lst.total_dead > c->lst.total_free + c->lst.total_dirty ||
221 c->lst.total_dead & 7) {
226 if (c->lst.total_dark < 0 ||
227 c->lst.total_dark > c->lst.total_free + c->lst.total_dirty ||
228 c->lst.total_dark & 7) {
236 ubifs_err("bad master node at offset %d error %d", c->mst_offs, err);
237 dbg_dump_node(c, c->mst_node);
242 * ubifs_read_master - read master node.
243 * @c: UBIFS file-system description object
245 * This function finds and reads the master node during file-system mount. If
246 * the flash is empty, it creates default master node as well. Returns zero in
247 * case of success and a negative error code in case of failure.
249 int ubifs_read_master(struct ubifs_info *c)
251 int err, old_leb_cnt;
253 c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL);
257 err = scan_for_master(c);
259 err = ubifs_recover_master_node(c);
262 * Note, we do not free 'c->mst_node' here because the
263 * unmount routine will take care of this.
268 /* Make sure that the recovery flag is clear */
269 c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY);
271 c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum);
272 c->highest_inum = le64_to_cpu(c->mst_node->highest_inum);
273 c->cmt_no = le64_to_cpu(c->mst_node->cmt_no);
274 c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum);
275 c->zroot.offs = le32_to_cpu(c->mst_node->root_offs);
276 c->zroot.len = le32_to_cpu(c->mst_node->root_len);
277 c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum);
278 c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum);
279 c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum);
280 c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs);
281 c->old_idx_sz = le64_to_cpu(c->mst_node->index_size);
282 c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum);
283 c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs);
284 c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum);
285 c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs);
286 c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum);
287 c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs);
288 c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum);
289 c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs);
290 c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum);
291 c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs);
292 c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs);
293 old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt);
294 c->lst.total_free = le64_to_cpu(c->mst_node->total_free);
295 c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty);
296 c->lst.total_used = le64_to_cpu(c->mst_node->total_used);
297 c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead);
298 c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark);
300 c->calc_idx_sz = c->old_idx_sz;
302 if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS))
305 if (old_leb_cnt != c->leb_cnt) {
306 /* The file system has been resized */
307 int growth = c->leb_cnt - old_leb_cnt;
309 if (c->leb_cnt < old_leb_cnt ||
310 c->leb_cnt < UBIFS_MIN_LEB_CNT) {
311 ubifs_err("bad leb_cnt on master node");
312 dbg_dump_node(c, c->mst_node);
316 dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs",
317 old_leb_cnt, c->leb_cnt);
318 c->lst.empty_lebs += growth;
319 c->lst.total_free += growth * (long long)c->leb_size;
320 c->lst.total_dark += growth * (long long)c->dark_wm;
323 * Reflect changes back onto the master node. N.B. the master
324 * node gets written immediately whenever mounting (or
325 * remounting) in read-write mode, so we do not need to write it
328 c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt);
329 c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs);
330 c->mst_node->total_free = cpu_to_le64(c->lst.total_free);
331 c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark);
334 err = validate_master(c);
338 err = dbg_old_index_check_init(c, &c->zroot);
344 * ubifs_write_master - write master node.
345 * @c: UBIFS file-system description object
347 * This function writes the master node. The caller has to take the
348 * @c->mst_mutex lock before calling this function. Returns zero in case of
349 * success and a negative error code in case of failure. The master node is
350 * written twice to enable recovery.
352 int ubifs_write_master(struct ubifs_info *c)
354 int err, lnum, offs, len;
359 lnum = UBIFS_MST_LNUM;
360 offs = c->mst_offs + c->mst_node_alsz;
361 len = UBIFS_MST_NODE_SZ;
363 if (offs + UBIFS_MST_NODE_SZ > c->leb_size) {
364 err = ubifs_leb_unmap(c, lnum);
371 c->mst_node->highest_inum = cpu_to_le64(c->highest_inum);
373 err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM);
380 err = ubifs_leb_unmap(c, lnum);
384 err = ubifs_write_node(c, c->mst_node, len, lnum, offs, UBI_SHORTTERM);