Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 1 | /* |
| 2 | * This file is part of UBIFS. |
| 3 | * |
| 4 | * Copyright (C) 2006-2008 Nokia Corporation. |
| 5 | * |
| 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. |
| 9 | * |
| 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 |
| 13 | * more details. |
| 14 | * |
| 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 |
| 18 | * |
| 19 | * Authors: Artem Bityutskiy (Битюцкий Артём) |
| 20 | * Adrian Hunter |
| 21 | */ |
| 22 | |
| 23 | /* |
| 24 | * This file implements UBIFS superblock. The superblock is stored at the first |
| 25 | * LEB of the volume and is never changed by UBIFS. Only user-space tools may |
| 26 | * change it. The superblock node mostly contains geometry information. |
| 27 | */ |
| 28 | |
| 29 | #include "ubifs.h" |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 30 | #include <linux/slab.h> |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 31 | #include <linux/random.h> |
Artem Bityutskiy | 4d61db4 | 2008-12-18 14:06:51 +0200 | [diff] [blame] | 32 | #include <linux/math64.h> |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 33 | |
| 34 | /* |
| 35 | * Default journal size in logical eraseblocks as a percent of total |
| 36 | * flash size. |
| 37 | */ |
| 38 | #define DEFAULT_JNL_PERCENT 5 |
| 39 | |
| 40 | /* Default maximum journal size in bytes */ |
| 41 | #define DEFAULT_MAX_JNL (32*1024*1024) |
| 42 | |
| 43 | /* Default indexing tree fanout */ |
| 44 | #define DEFAULT_FANOUT 8 |
| 45 | |
| 46 | /* Default number of data journal heads */ |
| 47 | #define DEFAULT_JHEADS_CNT 1 |
| 48 | |
| 49 | /* Default positions of different LEBs in the main area */ |
| 50 | #define DEFAULT_IDX_LEB 0 |
| 51 | #define DEFAULT_DATA_LEB 1 |
| 52 | #define DEFAULT_GC_LEB 2 |
| 53 | |
| 54 | /* Default number of LEB numbers in LPT's save table */ |
| 55 | #define DEFAULT_LSAVE_CNT 256 |
| 56 | |
| 57 | /* Default reserved pool size as a percent of maximum free space */ |
| 58 | #define DEFAULT_RP_PERCENT 5 |
| 59 | |
| 60 | /* The default maximum size of reserved pool in bytes */ |
| 61 | #define DEFAULT_MAX_RP_SIZE (5*1024*1024) |
| 62 | |
| 63 | /* Default time granularity in nanoseconds */ |
| 64 | #define DEFAULT_TIME_GRAN 1000000000 |
| 65 | |
| 66 | /** |
| 67 | * create_default_filesystem - format empty UBI volume. |
| 68 | * @c: UBIFS file-system description object |
| 69 | * |
| 70 | * This function creates default empty file-system. Returns zero in case of |
| 71 | * success and a negative error code in case of failure. |
| 72 | */ |
| 73 | static int create_default_filesystem(struct ubifs_info *c) |
| 74 | { |
| 75 | struct ubifs_sb_node *sup; |
| 76 | struct ubifs_mst_node *mst; |
| 77 | struct ubifs_idx_node *idx; |
| 78 | struct ubifs_branch *br; |
| 79 | struct ubifs_ino_node *ino; |
| 80 | struct ubifs_cs_node *cs; |
| 81 | union ubifs_key key; |
| 82 | int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first; |
| 83 | int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0; |
| 84 | int min_leb_cnt = UBIFS_MIN_LEB_CNT; |
Artem Bityutskiy | 4d61db4 | 2008-12-18 14:06:51 +0200 | [diff] [blame] | 85 | long long tmp64, main_bytes; |
Harvey Harrison | 0ecb952 | 2008-10-24 10:52:57 -0700 | [diff] [blame] | 86 | __le64 tmp_le64; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 87 | |
| 88 | /* Some functions called from here depend on the @c->key_len filed */ |
| 89 | c->key_len = UBIFS_SK_LEN; |
| 90 | |
| 91 | /* |
| 92 | * First of all, we have to calculate default file-system geometry - |
| 93 | * log size, journal size, etc. |
| 94 | */ |
| 95 | if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT) |
| 96 | /* We can first multiply then divide and have no overflow */ |
| 97 | jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100; |
| 98 | else |
| 99 | jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT; |
| 100 | |
| 101 | if (jnl_lebs < UBIFS_MIN_JNL_LEBS) |
| 102 | jnl_lebs = UBIFS_MIN_JNL_LEBS; |
| 103 | if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL) |
| 104 | jnl_lebs = DEFAULT_MAX_JNL / c->leb_size; |
| 105 | |
| 106 | /* |
| 107 | * The log should be large enough to fit reference nodes for all bud |
| 108 | * LEBs. Because buds do not have to start from the beginning of LEBs |
| 109 | * (half of the LEB may contain committed data), the log should |
| 110 | * generally be larger, make it twice as large. |
| 111 | */ |
| 112 | tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1; |
| 113 | log_lebs = tmp / c->leb_size; |
| 114 | /* Plus one LEB reserved for commit */ |
| 115 | log_lebs += 1; |
| 116 | if (c->leb_cnt - min_leb_cnt > 8) { |
| 117 | /* And some extra space to allow writes while committing */ |
| 118 | log_lebs += 1; |
| 119 | min_leb_cnt += 1; |
| 120 | } |
| 121 | |
| 122 | max_buds = jnl_lebs - log_lebs; |
| 123 | if (max_buds < UBIFS_MIN_BUD_LEBS) |
| 124 | max_buds = UBIFS_MIN_BUD_LEBS; |
| 125 | |
| 126 | /* |
| 127 | * Orphan nodes are stored in a separate area. One node can store a lot |
| 128 | * of orphan inode numbers, but when new orphan comes we just add a new |
| 129 | * orphan node. At some point the nodes are consolidated into one |
| 130 | * orphan node. |
| 131 | */ |
| 132 | orph_lebs = UBIFS_MIN_ORPH_LEBS; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 133 | if (c->leb_cnt - min_leb_cnt > 1) |
| 134 | /* |
| 135 | * For debugging purposes it is better to have at least 2 |
| 136 | * orphan LEBs, because the orphan subsystem would need to do |
| 137 | * consolidations and would be stressed more. |
| 138 | */ |
| 139 | orph_lebs += 1; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 140 | |
| 141 | main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs; |
| 142 | main_lebs -= orph_lebs; |
| 143 | |
| 144 | lpt_first = UBIFS_LOG_LNUM + log_lebs; |
| 145 | c->lsave_cnt = DEFAULT_LSAVE_CNT; |
| 146 | c->max_leb_cnt = c->leb_cnt; |
| 147 | err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs, |
| 148 | &big_lpt); |
| 149 | if (err) |
| 150 | return err; |
| 151 | |
| 152 | dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first, |
| 153 | lpt_first + lpt_lebs - 1); |
| 154 | |
| 155 | main_first = c->leb_cnt - main_lebs; |
| 156 | |
| 157 | /* Create default superblock */ |
| 158 | tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); |
| 159 | sup = kzalloc(tmp, GFP_KERNEL); |
| 160 | if (!sup) |
| 161 | return -ENOMEM; |
| 162 | |
Artem Bityutskiy | 4d61db4 | 2008-12-18 14:06:51 +0200 | [diff] [blame] | 163 | tmp64 = (long long)max_buds * c->leb_size; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 164 | if (big_lpt) |
| 165 | sup_flags |= UBIFS_FLG_BIGLPT; |
| 166 | |
| 167 | sup->ch.node_type = UBIFS_SB_NODE; |
| 168 | sup->key_hash = UBIFS_KEY_HASH_R5; |
| 169 | sup->flags = cpu_to_le32(sup_flags); |
| 170 | sup->min_io_size = cpu_to_le32(c->min_io_size); |
| 171 | sup->leb_size = cpu_to_le32(c->leb_size); |
| 172 | sup->leb_cnt = cpu_to_le32(c->leb_cnt); |
| 173 | sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt); |
| 174 | sup->max_bud_bytes = cpu_to_le64(tmp64); |
| 175 | sup->log_lebs = cpu_to_le32(log_lebs); |
| 176 | sup->lpt_lebs = cpu_to_le32(lpt_lebs); |
| 177 | sup->orph_lebs = cpu_to_le32(orph_lebs); |
| 178 | sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT); |
| 179 | sup->fanout = cpu_to_le32(DEFAULT_FANOUT); |
| 180 | sup->lsave_cnt = cpu_to_le32(c->lsave_cnt); |
| 181 | sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 182 | sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN); |
Artem Bityutskiy | 553dea4 | 2008-11-01 14:57:49 +0200 | [diff] [blame] | 183 | if (c->mount_opts.override_compr) |
| 184 | sup->default_compr = cpu_to_le16(c->mount_opts.compr_type); |
| 185 | else |
| 186 | sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 187 | |
| 188 | generate_random_uuid(sup->uuid); |
| 189 | |
Artem Bityutskiy | 4d61db4 | 2008-12-18 14:06:51 +0200 | [diff] [blame] | 190 | main_bytes = (long long)main_lebs * c->leb_size; |
| 191 | tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 192 | if (tmp64 > DEFAULT_MAX_RP_SIZE) |
| 193 | tmp64 = DEFAULT_MAX_RP_SIZE; |
| 194 | sup->rp_size = cpu_to_le64(tmp64); |
Artem Bityutskiy | 963f0cf | 2009-03-26 12:51:21 +0200 | [diff] [blame] | 195 | sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 196 | |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 197 | err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 198 | kfree(sup); |
| 199 | if (err) |
| 200 | return err; |
| 201 | |
| 202 | dbg_gen("default superblock created at LEB 0:0"); |
| 203 | |
| 204 | /* Create default master node */ |
| 205 | mst = kzalloc(c->mst_node_alsz, GFP_KERNEL); |
| 206 | if (!mst) |
| 207 | return -ENOMEM; |
| 208 | |
| 209 | mst->ch.node_type = UBIFS_MST_NODE; |
| 210 | mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM); |
| 211 | mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO); |
| 212 | mst->cmt_no = 0; |
| 213 | mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); |
| 214 | mst->root_offs = 0; |
| 215 | tmp = ubifs_idx_node_sz(c, 1); |
| 216 | mst->root_len = cpu_to_le32(tmp); |
| 217 | mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB); |
| 218 | mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); |
| 219 | mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size)); |
| 220 | mst->index_size = cpu_to_le64(ALIGN(tmp, 8)); |
| 221 | mst->lpt_lnum = cpu_to_le32(c->lpt_lnum); |
| 222 | mst->lpt_offs = cpu_to_le32(c->lpt_offs); |
| 223 | mst->nhead_lnum = cpu_to_le32(c->nhead_lnum); |
| 224 | mst->nhead_offs = cpu_to_le32(c->nhead_offs); |
| 225 | mst->ltab_lnum = cpu_to_le32(c->ltab_lnum); |
| 226 | mst->ltab_offs = cpu_to_le32(c->ltab_offs); |
| 227 | mst->lsave_lnum = cpu_to_le32(c->lsave_lnum); |
| 228 | mst->lsave_offs = cpu_to_le32(c->lsave_offs); |
| 229 | mst->lscan_lnum = cpu_to_le32(main_first); |
| 230 | mst->empty_lebs = cpu_to_le32(main_lebs - 2); |
| 231 | mst->idx_lebs = cpu_to_le32(1); |
| 232 | mst->leb_cnt = cpu_to_le32(c->leb_cnt); |
| 233 | |
| 234 | /* Calculate lprops statistics */ |
| 235 | tmp64 = main_bytes; |
| 236 | tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); |
| 237 | tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); |
| 238 | mst->total_free = cpu_to_le64(tmp64); |
| 239 | |
| 240 | tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); |
| 241 | ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) - |
| 242 | UBIFS_INO_NODE_SZ; |
| 243 | tmp64 += ino_waste; |
| 244 | tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8); |
| 245 | mst->total_dirty = cpu_to_le64(tmp64); |
| 246 | |
| 247 | /* The indexing LEB does not contribute to dark space */ |
srimugunthan dhandapani | 7606f85 | 2011-08-26 16:08:39 +0530 | [diff] [blame] | 248 | tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 249 | mst->total_dark = cpu_to_le64(tmp64); |
| 250 | |
| 251 | mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ); |
| 252 | |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 253 | err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 254 | if (err) { |
| 255 | kfree(mst); |
| 256 | return err; |
| 257 | } |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 258 | err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, |
| 259 | 0); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 260 | kfree(mst); |
| 261 | if (err) |
| 262 | return err; |
| 263 | |
| 264 | dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM); |
| 265 | |
| 266 | /* Create the root indexing node */ |
| 267 | tmp = ubifs_idx_node_sz(c, 1); |
| 268 | idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL); |
| 269 | if (!idx) |
| 270 | return -ENOMEM; |
| 271 | |
| 272 | c->key_fmt = UBIFS_SIMPLE_KEY_FMT; |
| 273 | c->key_hash = key_r5_hash; |
| 274 | |
| 275 | idx->ch.node_type = UBIFS_IDX_NODE; |
| 276 | idx->child_cnt = cpu_to_le16(1); |
| 277 | ino_key_init(c, &key, UBIFS_ROOT_INO); |
| 278 | br = ubifs_idx_branch(c, idx, 0); |
| 279 | key_write_idx(c, &key, &br->key); |
| 280 | br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB); |
| 281 | br->len = cpu_to_le32(UBIFS_INO_NODE_SZ); |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 282 | err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 283 | kfree(idx); |
| 284 | if (err) |
| 285 | return err; |
| 286 | |
| 287 | dbg_gen("default root indexing node created LEB %d:0", |
| 288 | main_first + DEFAULT_IDX_LEB); |
| 289 | |
| 290 | /* Create default root inode */ |
| 291 | tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); |
| 292 | ino = kzalloc(tmp, GFP_KERNEL); |
| 293 | if (!ino) |
| 294 | return -ENOMEM; |
| 295 | |
| 296 | ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO); |
| 297 | ino->ch.node_type = UBIFS_INO_NODE; |
| 298 | ino->creat_sqnum = cpu_to_le64(++c->max_sqnum); |
| 299 | ino->nlink = cpu_to_le32(2); |
Harvey Harrison | 0ecb952 | 2008-10-24 10:52:57 -0700 | [diff] [blame] | 300 | tmp_le64 = cpu_to_le64(CURRENT_TIME_SEC.tv_sec); |
| 301 | ino->atime_sec = tmp_le64; |
| 302 | ino->ctime_sec = tmp_le64; |
| 303 | ino->mtime_sec = tmp_le64; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 304 | ino->atime_nsec = 0; |
| 305 | ino->ctime_nsec = 0; |
| 306 | ino->mtime_nsec = 0; |
| 307 | ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO); |
| 308 | ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ); |
| 309 | |
| 310 | /* Set compression enabled by default */ |
| 311 | ino->flags = cpu_to_le32(UBIFS_COMPR_FL); |
| 312 | |
| 313 | err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ, |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 314 | main_first + DEFAULT_DATA_LEB, 0); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 315 | kfree(ino); |
| 316 | if (err) |
| 317 | return err; |
| 318 | |
| 319 | dbg_gen("root inode created at LEB %d:0", |
| 320 | main_first + DEFAULT_DATA_LEB); |
| 321 | |
| 322 | /* |
| 323 | * The first node in the log has to be the commit start node. This is |
| 324 | * always the case during normal file-system operation. Write a fake |
| 325 | * commit start node to the log. |
| 326 | */ |
| 327 | tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size); |
| 328 | cs = kzalloc(tmp, GFP_KERNEL); |
| 329 | if (!cs) |
| 330 | return -ENOMEM; |
| 331 | |
| 332 | cs->ch.node_type = UBIFS_CS_NODE; |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 333 | err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, 0); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 334 | kfree(cs); |
hujianyang | 6dcfb80 | 2014-06-11 10:38:45 +0800 | [diff] [blame] | 335 | if (err) |
| 336 | return err; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 337 | |
| 338 | ubifs_msg("default file-system created"); |
| 339 | return 0; |
| 340 | } |
| 341 | |
| 342 | /** |
| 343 | * validate_sb - validate superblock node. |
| 344 | * @c: UBIFS file-system description object |
| 345 | * @sup: superblock node |
| 346 | * |
| 347 | * This function validates superblock node @sup. Since most of data was read |
| 348 | * from the superblock and stored in @c, the function validates fields in @c |
| 349 | * instead. Returns zero in case of success and %-EINVAL in case of validation |
| 350 | * failure. |
| 351 | */ |
| 352 | static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup) |
| 353 | { |
| 354 | long long max_bytes; |
| 355 | int err = 1, min_leb_cnt; |
| 356 | |
| 357 | if (!c->key_hash) { |
| 358 | err = 2; |
| 359 | goto failed; |
| 360 | } |
| 361 | |
| 362 | if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) { |
| 363 | err = 3; |
| 364 | goto failed; |
| 365 | } |
| 366 | |
| 367 | if (le32_to_cpu(sup->min_io_size) != c->min_io_size) { |
| 368 | ubifs_err("min. I/O unit mismatch: %d in superblock, %d real", |
| 369 | le32_to_cpu(sup->min_io_size), c->min_io_size); |
| 370 | goto failed; |
| 371 | } |
| 372 | |
| 373 | if (le32_to_cpu(sup->leb_size) != c->leb_size) { |
| 374 | ubifs_err("LEB size mismatch: %d in superblock, %d real", |
| 375 | le32_to_cpu(sup->leb_size), c->leb_size); |
| 376 | goto failed; |
| 377 | } |
| 378 | |
| 379 | if (c->log_lebs < UBIFS_MIN_LOG_LEBS || |
| 380 | c->lpt_lebs < UBIFS_MIN_LPT_LEBS || |
| 381 | c->orph_lebs < UBIFS_MIN_ORPH_LEBS || |
| 382 | c->main_lebs < UBIFS_MIN_MAIN_LEBS) { |
| 383 | err = 4; |
| 384 | goto failed; |
| 385 | } |
| 386 | |
| 387 | /* |
| 388 | * Calculate minimum allowed amount of main area LEBs. This is very |
| 389 | * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we |
| 390 | * have just read from the superblock. |
| 391 | */ |
| 392 | min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs; |
| 393 | min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6; |
| 394 | |
| 395 | if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) { |
Artem Bityutskiy | 79fda51 | 2012-08-27 13:34:09 +0300 | [diff] [blame] | 396 | ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, %d minimum required", |
| 397 | c->leb_cnt, c->vi.size, min_leb_cnt); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 398 | goto failed; |
| 399 | } |
| 400 | |
| 401 | if (c->max_leb_cnt < c->leb_cnt) { |
| 402 | ubifs_err("max. LEB count %d less than LEB count %d", |
| 403 | c->max_leb_cnt, c->leb_cnt); |
| 404 | goto failed; |
| 405 | } |
| 406 | |
| 407 | if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) { |
Artem Bityutskiy | 5a1f36c | 2012-03-07 16:29:45 +0200 | [diff] [blame] | 408 | ubifs_err("too few main LEBs count %d, must be at least %d", |
| 409 | c->main_lebs, UBIFS_MIN_MAIN_LEBS); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 410 | goto failed; |
| 411 | } |
| 412 | |
Artem Bityutskiy | 5a1f36c | 2012-03-07 16:29:45 +0200 | [diff] [blame] | 413 | max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS; |
| 414 | if (c->max_bud_bytes < max_bytes) { |
Artem Bityutskiy | 79fda51 | 2012-08-27 13:34:09 +0300 | [diff] [blame] | 415 | ubifs_err("too small journal (%lld bytes), must be at least %lld bytes", |
| 416 | c->max_bud_bytes, max_bytes); |
Artem Bityutskiy | 5a1f36c | 2012-03-07 16:29:45 +0200 | [diff] [blame] | 417 | goto failed; |
| 418 | } |
| 419 | |
| 420 | max_bytes = (long long)c->leb_size * c->main_lebs; |
| 421 | if (c->max_bud_bytes > max_bytes) { |
Artem Bityutskiy | 79fda51 | 2012-08-27 13:34:09 +0300 | [diff] [blame] | 422 | ubifs_err("too large journal size (%lld bytes), only %lld bytes available in the main area", |
Artem Bityutskiy | 5a1f36c | 2012-03-07 16:29:45 +0200 | [diff] [blame] | 423 | c->max_bud_bytes, max_bytes); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 424 | goto failed; |
| 425 | } |
| 426 | |
| 427 | if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 || |
| 428 | c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) { |
| 429 | err = 9; |
| 430 | goto failed; |
| 431 | } |
| 432 | |
| 433 | if (c->fanout < UBIFS_MIN_FANOUT || |
| 434 | ubifs_idx_node_sz(c, c->fanout) > c->leb_size) { |
| 435 | err = 10; |
| 436 | goto failed; |
| 437 | } |
| 438 | |
| 439 | if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT && |
| 440 | c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - |
| 441 | c->log_lebs - c->lpt_lebs - c->orph_lebs)) { |
| 442 | err = 11; |
| 443 | goto failed; |
| 444 | } |
| 445 | |
| 446 | if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs + |
| 447 | c->orph_lebs + c->main_lebs != c->leb_cnt) { |
| 448 | err = 12; |
| 449 | goto failed; |
| 450 | } |
| 451 | |
hujianyang | b793a8c | 2014-06-11 10:42:52 +0800 | [diff] [blame] | 452 | if (c->default_compr >= UBIFS_COMPR_TYPES_CNT) { |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 453 | err = 13; |
| 454 | goto failed; |
| 455 | } |
| 456 | |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 457 | if (c->rp_size < 0 || max_bytes < c->rp_size) { |
| 458 | err = 14; |
| 459 | goto failed; |
| 460 | } |
| 461 | |
| 462 | if (le32_to_cpu(sup->time_gran) > 1000000000 || |
| 463 | le32_to_cpu(sup->time_gran) < 1) { |
| 464 | err = 15; |
| 465 | goto failed; |
| 466 | } |
| 467 | |
| 468 | return 0; |
| 469 | |
| 470 | failed: |
| 471 | ubifs_err("bad superblock, error %d", err); |
Artem Bityutskiy | edf6be2 | 2012-05-16 19:15:56 +0300 | [diff] [blame] | 472 | ubifs_dump_node(c, sup); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 473 | return -EINVAL; |
| 474 | } |
| 475 | |
| 476 | /** |
| 477 | * ubifs_read_sb_node - read superblock node. |
| 478 | * @c: UBIFS file-system description object |
| 479 | * |
| 480 | * This function returns a pointer to the superblock node or a negative error |
Artem Bityutskiy | eaeee24 | 2011-05-06 17:08:56 +0300 | [diff] [blame] | 481 | * code. Note, the user of this function is responsible of kfree()'ing the |
| 482 | * returned superblock buffer. |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 483 | */ |
| 484 | struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c) |
| 485 | { |
| 486 | struct ubifs_sb_node *sup; |
| 487 | int err; |
| 488 | |
| 489 | sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS); |
| 490 | if (!sup) |
| 491 | return ERR_PTR(-ENOMEM); |
| 492 | |
| 493 | err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ, |
| 494 | UBIFS_SB_LNUM, 0); |
| 495 | if (err) { |
| 496 | kfree(sup); |
| 497 | return ERR_PTR(err); |
| 498 | } |
| 499 | |
| 500 | return sup; |
| 501 | } |
| 502 | |
| 503 | /** |
| 504 | * ubifs_write_sb_node - write superblock node. |
| 505 | * @c: UBIFS file-system description object |
| 506 | * @sup: superblock node read with 'ubifs_read_sb_node()' |
| 507 | * |
| 508 | * This function returns %0 on success and a negative error code on failure. |
| 509 | */ |
| 510 | int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup) |
| 511 | { |
| 512 | int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); |
| 513 | |
| 514 | ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1); |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 515 | return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 516 | } |
| 517 | |
| 518 | /** |
| 519 | * ubifs_read_superblock - read superblock. |
| 520 | * @c: UBIFS file-system description object |
| 521 | * |
| 522 | * This function finds, reads and checks the superblock. If an empty UBI volume |
| 523 | * is being mounted, this function creates default superblock. Returns zero in |
| 524 | * case of success, and a negative error code in case of failure. |
| 525 | */ |
| 526 | int ubifs_read_superblock(struct ubifs_info *c) |
| 527 | { |
| 528 | int err, sup_flags; |
| 529 | struct ubifs_sb_node *sup; |
| 530 | |
| 531 | if (c->empty) { |
| 532 | err = create_default_filesystem(c); |
| 533 | if (err) |
| 534 | return err; |
| 535 | } |
| 536 | |
| 537 | sup = ubifs_read_sb_node(c); |
| 538 | if (IS_ERR(sup)) |
| 539 | return PTR_ERR(sup); |
| 540 | |
Artem Bityutskiy | 963f0cf | 2009-03-26 12:51:21 +0200 | [diff] [blame] | 541 | c->fmt_version = le32_to_cpu(sup->fmt_version); |
| 542 | c->ro_compat_version = le32_to_cpu(sup->ro_compat_version); |
| 543 | |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 544 | /* |
| 545 | * The software supports all previous versions but not future versions, |
| 546 | * due to the unavailability of time-travelling equipment. |
| 547 | */ |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 548 | if (c->fmt_version > UBIFS_FORMAT_VERSION) { |
Artem Bityutskiy | 2ef1329 | 2010-09-19 18:34:26 +0300 | [diff] [blame] | 549 | ubifs_assert(!c->ro_media || c->ro_mount); |
| 550 | if (!c->ro_mount || |
Artem Bityutskiy | 963f0cf | 2009-03-26 12:51:21 +0200 | [diff] [blame] | 551 | c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) { |
Artem Bityutskiy | 79fda51 | 2012-08-27 13:34:09 +0300 | [diff] [blame] | 552 | ubifs_err("on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d", |
| 553 | c->fmt_version, c->ro_compat_version, |
| 554 | UBIFS_FORMAT_VERSION, |
Artem Bityutskiy | 963f0cf | 2009-03-26 12:51:21 +0200 | [diff] [blame] | 555 | UBIFS_RO_COMPAT_VERSION); |
| 556 | if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) { |
| 557 | ubifs_msg("only R/O mounting is possible"); |
| 558 | err = -EROFS; |
| 559 | } else |
| 560 | err = -EINVAL; |
| 561 | goto out; |
| 562 | } |
| 563 | |
| 564 | /* |
| 565 | * The FS is mounted R/O, and the media format is |
| 566 | * R/O-compatible with the UBIFS implementation, so we can |
| 567 | * mount. |
| 568 | */ |
| 569 | c->rw_incompat = 1; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 570 | } |
| 571 | |
| 572 | if (c->fmt_version < 3) { |
| 573 | ubifs_err("on-flash format version %d is not supported", |
| 574 | c->fmt_version); |
| 575 | err = -EINVAL; |
| 576 | goto out; |
| 577 | } |
| 578 | |
| 579 | switch (sup->key_hash) { |
| 580 | case UBIFS_KEY_HASH_R5: |
| 581 | c->key_hash = key_r5_hash; |
| 582 | c->key_hash_type = UBIFS_KEY_HASH_R5; |
| 583 | break; |
| 584 | |
| 585 | case UBIFS_KEY_HASH_TEST: |
| 586 | c->key_hash = key_test_hash; |
| 587 | c->key_hash_type = UBIFS_KEY_HASH_TEST; |
| 588 | break; |
| 589 | }; |
| 590 | |
| 591 | c->key_fmt = sup->key_fmt; |
| 592 | |
| 593 | switch (c->key_fmt) { |
| 594 | case UBIFS_SIMPLE_KEY_FMT: |
| 595 | c->key_len = UBIFS_SK_LEN; |
| 596 | break; |
| 597 | default: |
| 598 | ubifs_err("unsupported key format"); |
| 599 | err = -EINVAL; |
| 600 | goto out; |
| 601 | } |
| 602 | |
| 603 | c->leb_cnt = le32_to_cpu(sup->leb_cnt); |
| 604 | c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt); |
| 605 | c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes); |
| 606 | c->log_lebs = le32_to_cpu(sup->log_lebs); |
| 607 | c->lpt_lebs = le32_to_cpu(sup->lpt_lebs); |
| 608 | c->orph_lebs = le32_to_cpu(sup->orph_lebs); |
| 609 | c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT; |
| 610 | c->fanout = le32_to_cpu(sup->fanout); |
| 611 | c->lsave_cnt = le32_to_cpu(sup->lsave_cnt); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 612 | c->rp_size = le64_to_cpu(sup->rp_size); |
Eric W. Biederman | 39241be | 2012-02-07 15:50:56 -0800 | [diff] [blame] | 613 | c->rp_uid = make_kuid(&init_user_ns, le32_to_cpu(sup->rp_uid)); |
| 614 | c->rp_gid = make_kgid(&init_user_ns, le32_to_cpu(sup->rp_gid)); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 615 | sup_flags = le32_to_cpu(sup->flags); |
Artem Bityutskiy | 553dea4 | 2008-11-01 14:57:49 +0200 | [diff] [blame] | 616 | if (!c->mount_opts.override_compr) |
| 617 | c->default_compr = le16_to_cpu(sup->default_compr); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 618 | |
| 619 | c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 620 | memcpy(&c->uuid, &sup->uuid, 16); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 621 | c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); |
Matthew L. Creech | 9f58d35 | 2011-05-05 16:33:20 -0400 | [diff] [blame] | 622 | c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP); |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 623 | |
| 624 | /* Automatically increase file system size to the maximum size */ |
| 625 | c->old_leb_cnt = c->leb_cnt; |
| 626 | if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) { |
| 627 | c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size); |
Artem Bityutskiy | 2ef1329 | 2010-09-19 18:34:26 +0300 | [diff] [blame] | 628 | if (c->ro_mount) |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 629 | dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs", |
| 630 | c->old_leb_cnt, c->leb_cnt); |
| 631 | else { |
| 632 | dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs", |
| 633 | c->old_leb_cnt, c->leb_cnt); |
| 634 | sup->leb_cnt = cpu_to_le32(c->leb_cnt); |
| 635 | err = ubifs_write_sb_node(c, sup); |
| 636 | if (err) |
| 637 | goto out; |
| 638 | c->old_leb_cnt = c->leb_cnt; |
| 639 | } |
| 640 | } |
| 641 | |
| 642 | c->log_bytes = (long long)c->log_lebs * c->leb_size; |
| 643 | c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1; |
| 644 | c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs; |
| 645 | c->lpt_last = c->lpt_first + c->lpt_lebs - 1; |
| 646 | c->orph_first = c->lpt_last + 1; |
| 647 | c->orph_last = c->orph_first + c->orph_lebs - 1; |
| 648 | c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS; |
| 649 | c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs; |
| 650 | c->main_first = c->leb_cnt - c->main_lebs; |
Artem Bityutskiy | 1e51764 | 2008-07-14 19:08:37 +0300 | [diff] [blame] | 651 | |
| 652 | err = validate_sb(c, sup); |
| 653 | out: |
| 654 | kfree(sup); |
| 655 | return err; |
| 656 | } |
Matthew L. Creech | 6554a65 | 2011-05-06 18:58:22 -0400 | [diff] [blame] | 657 | |
| 658 | /** |
| 659 | * fixup_leb - fixup/unmap an LEB containing free space. |
| 660 | * @c: UBIFS file-system description object |
| 661 | * @lnum: the LEB number to fix up |
| 662 | * @len: number of used bytes in LEB (starting at offset 0) |
| 663 | * |
| 664 | * This function reads the contents of the given LEB number @lnum, then fixes |
| 665 | * it up, so that empty min. I/O units in the end of LEB are actually erased on |
| 666 | * flash (rather than being just all-0xff real data). If the LEB is completely |
| 667 | * empty, it is simply unmapped. |
| 668 | */ |
| 669 | static int fixup_leb(struct ubifs_info *c, int lnum, int len) |
| 670 | { |
| 671 | int err; |
| 672 | |
| 673 | ubifs_assert(len >= 0); |
| 674 | ubifs_assert(len % c->min_io_size == 0); |
| 675 | ubifs_assert(len < c->leb_size); |
| 676 | |
| 677 | if (len == 0) { |
| 678 | dbg_mnt("unmap empty LEB %d", lnum); |
Artem Bityutskiy | d3b2578 | 2011-06-03 14:22:05 +0300 | [diff] [blame] | 679 | return ubifs_leb_unmap(c, lnum); |
Matthew L. Creech | 6554a65 | 2011-05-06 18:58:22 -0400 | [diff] [blame] | 680 | } |
| 681 | |
| 682 | dbg_mnt("fixup LEB %d, data len %d", lnum, len); |
Artem Bityutskiy | d304820 | 2011-06-03 14:03:25 +0300 | [diff] [blame] | 683 | err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1); |
Matthew L. Creech | 6554a65 | 2011-05-06 18:58:22 -0400 | [diff] [blame] | 684 | if (err) |
| 685 | return err; |
| 686 | |
Richard Weinberger | b36a261 | 2012-05-14 17:55:51 +0200 | [diff] [blame] | 687 | return ubifs_leb_change(c, lnum, c->sbuf, len); |
Matthew L. Creech | 6554a65 | 2011-05-06 18:58:22 -0400 | [diff] [blame] | 688 | } |
| 689 | |
| 690 | /** |
| 691 | * fixup_free_space - find & remap all LEBs containing free space. |
| 692 | * @c: UBIFS file-system description object |
| 693 | * |
| 694 | * This function walks through all LEBs in the filesystem and fiexes up those |
| 695 | * containing free/empty space. |
| 696 | */ |
| 697 | static int fixup_free_space(struct ubifs_info *c) |
| 698 | { |
| 699 | int lnum, err = 0; |
| 700 | struct ubifs_lprops *lprops; |
| 701 | |
| 702 | ubifs_get_lprops(c); |
| 703 | |
| 704 | /* Fixup LEBs in the master area */ |
| 705 | for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) { |
| 706 | err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz); |
| 707 | if (err) |
| 708 | goto out; |
| 709 | } |
| 710 | |
| 711 | /* Unmap unused log LEBs */ |
| 712 | lnum = ubifs_next_log_lnum(c, c->lhead_lnum); |
| 713 | while (lnum != c->ltail_lnum) { |
| 714 | err = fixup_leb(c, lnum, 0); |
| 715 | if (err) |
| 716 | goto out; |
| 717 | lnum = ubifs_next_log_lnum(c, lnum); |
| 718 | } |
| 719 | |
Artem Bityutskiy | c672793 | 2012-07-14 14:33:09 +0300 | [diff] [blame] | 720 | /* |
| 721 | * Fixup the log head which contains the only a CS node at the |
| 722 | * beginning. |
| 723 | */ |
| 724 | err = fixup_leb(c, c->lhead_lnum, |
| 725 | ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size)); |
Matthew L. Creech | 6554a65 | 2011-05-06 18:58:22 -0400 | [diff] [blame] | 726 | if (err) |
| 727 | goto out; |
| 728 | |
| 729 | /* Fixup LEBs in the LPT area */ |
| 730 | for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) { |
| 731 | int free = c->ltab[lnum - c->lpt_first].free; |
| 732 | |
| 733 | if (free > 0) { |
| 734 | err = fixup_leb(c, lnum, c->leb_size - free); |
| 735 | if (err) |
| 736 | goto out; |
| 737 | } |
| 738 | } |
| 739 | |
| 740 | /* Unmap LEBs in the orphans area */ |
| 741 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { |
| 742 | err = fixup_leb(c, lnum, 0); |
| 743 | if (err) |
| 744 | goto out; |
| 745 | } |
| 746 | |
| 747 | /* Fixup LEBs in the main area */ |
| 748 | for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) { |
| 749 | lprops = ubifs_lpt_lookup(c, lnum); |
| 750 | if (IS_ERR(lprops)) { |
| 751 | err = PTR_ERR(lprops); |
| 752 | goto out; |
| 753 | } |
| 754 | |
| 755 | if (lprops->free > 0) { |
| 756 | err = fixup_leb(c, lnum, c->leb_size - lprops->free); |
| 757 | if (err) |
| 758 | goto out; |
| 759 | } |
| 760 | } |
| 761 | |
| 762 | out: |
| 763 | ubifs_release_lprops(c); |
| 764 | return err; |
| 765 | } |
| 766 | |
| 767 | /** |
| 768 | * ubifs_fixup_free_space - find & fix all LEBs with free space. |
| 769 | * @c: UBIFS file-system description object |
| 770 | * |
| 771 | * This function fixes up LEBs containing free space on first mount, if the |
| 772 | * appropriate flag was set when the FS was created. Each LEB with one or more |
| 773 | * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure |
| 774 | * the free space is actually erased. E.g., this is necessary for some NAND |
| 775 | * chips, since the free space may have been programmed like real "0xff" data |
| 776 | * (generating a non-0xff ECC), causing future writes to the not-really-erased |
| 777 | * NAND pages to behave badly. After the space is fixed up, the superblock flag |
| 778 | * is cleared, so that this is skipped for all future mounts. |
| 779 | */ |
| 780 | int ubifs_fixup_free_space(struct ubifs_info *c) |
| 781 | { |
| 782 | int err; |
| 783 | struct ubifs_sb_node *sup; |
| 784 | |
| 785 | ubifs_assert(c->space_fixup); |
| 786 | ubifs_assert(!c->ro_mount); |
| 787 | |
| 788 | ubifs_msg("start fixing up free space"); |
| 789 | |
| 790 | err = fixup_free_space(c); |
| 791 | if (err) |
| 792 | return err; |
| 793 | |
| 794 | sup = ubifs_read_sb_node(c); |
| 795 | if (IS_ERR(sup)) |
| 796 | return PTR_ERR(sup); |
| 797 | |
| 798 | /* Free-space fixup is no longer required */ |
| 799 | c->space_fixup = 0; |
| 800 | sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP); |
| 801 | |
| 802 | err = ubifs_write_sb_node(c, sup); |
| 803 | kfree(sup); |
| 804 | if (err) |
| 805 | return err; |
| 806 | |
| 807 | ubifs_msg("free space fixup complete"); |
| 808 | return err; |
| 809 | } |