Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * vfsv0 quota IO operations on file |
| 3 | */ |
| 4 | |
| 5 | #include <linux/errno.h> |
| 6 | #include <linux/fs.h> |
| 7 | #include <linux/mount.h> |
| 8 | #include <linux/dqblk_v2.h> |
| 9 | #include <linux/quotaio_v2.h> |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/slab.h> |
Jan Kara | 74abb98 | 2008-07-25 01:46:51 -0700 | [diff] [blame] | 14 | #include <linux/quotaops.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | |
| 16 | #include <asm/byteorder.h> |
| 17 | |
| 18 | MODULE_AUTHOR("Jan Kara"); |
| 19 | MODULE_DESCRIPTION("Quota format v2 support"); |
| 20 | MODULE_LICENSE("GPL"); |
| 21 | |
| 22 | #define __QUOTA_V2_PARANOIA |
| 23 | |
| 24 | typedef char *dqbuf_t; |
| 25 | |
| 26 | #define GETIDINDEX(id, depth) (((id) >> ((V2_DQTREEDEPTH-(depth)-1)*8)) & 0xff) |
| 27 | #define GETENTRIES(buf) ((struct v2_disk_dqblk *)(((char *)buf)+sizeof(struct v2_disk_dqdbheader))) |
| 28 | |
Jan Kara | 1209546 | 2008-08-20 14:45:12 +0200 | [diff] [blame] | 29 | #define QUOTABLOCK_BITS 10 |
| 30 | #define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS) |
| 31 | |
| 32 | static inline qsize_t v2_stoqb(qsize_t space) |
| 33 | { |
| 34 | return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS; |
| 35 | } |
| 36 | |
| 37 | static inline qsize_t v2_qbtos(qsize_t blocks) |
| 38 | { |
| 39 | return blocks << QUOTABLOCK_BITS; |
| 40 | } |
| 41 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | /* Check whether given file is really vfsv0 quotafile */ |
| 43 | static int v2_check_quota_file(struct super_block *sb, int type) |
| 44 | { |
| 45 | struct v2_disk_dqheader dqhead; |
| 46 | ssize_t size; |
| 47 | static const uint quota_magics[] = V2_INITQMAGICS; |
| 48 | static const uint quota_versions[] = V2_INITQVERSIONS; |
| 49 | |
| 50 | size = sb->s_op->quota_read(sb, type, (char *)&dqhead, sizeof(struct v2_disk_dqheader), 0); |
| 51 | if (size != sizeof(struct v2_disk_dqheader)) { |
Andrew Morton | 8c17e1e | 2006-02-03 03:04:03 -0800 | [diff] [blame] | 52 | printk("quota_v2: failed read expected=%zd got=%zd\n", |
Valdis.Kletnieks@vt.edu | 3135806 | 2006-01-14 13:21:10 -0800 | [diff] [blame] | 53 | sizeof(struct v2_disk_dqheader), size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | return 0; |
| 55 | } |
| 56 | if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] || |
| 57 | le32_to_cpu(dqhead.dqh_version) != quota_versions[type]) |
| 58 | return 0; |
| 59 | return 1; |
| 60 | } |
| 61 | |
| 62 | /* Read information header from quota file */ |
| 63 | static int v2_read_file_info(struct super_block *sb, int type) |
| 64 | { |
| 65 | struct v2_disk_dqinfo dinfo; |
| 66 | struct mem_dqinfo *info = sb_dqopt(sb)->info+type; |
| 67 | ssize_t size; |
| 68 | |
| 69 | size = sb->s_op->quota_read(sb, type, (char *)&dinfo, |
| 70 | sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF); |
| 71 | if (size != sizeof(struct v2_disk_dqinfo)) { |
| 72 | printk(KERN_WARNING "Can't read info structure on device %s.\n", |
| 73 | sb->s_id); |
| 74 | return -1; |
| 75 | } |
Andrew Perepechko | 338bf9a | 2008-04-28 02:14:31 -0700 | [diff] [blame] | 76 | /* limits are stored as unsigned 32-bit data */ |
| 77 | info->dqi_maxblimit = 0xffffffff; |
| 78 | info->dqi_maxilimit = 0xffffffff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace); |
| 80 | info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace); |
| 81 | info->dqi_flags = le32_to_cpu(dinfo.dqi_flags); |
| 82 | info->u.v2_i.dqi_blocks = le32_to_cpu(dinfo.dqi_blocks); |
| 83 | info->u.v2_i.dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk); |
| 84 | info->u.v2_i.dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry); |
| 85 | return 0; |
| 86 | } |
| 87 | |
| 88 | /* Write information header to quota file */ |
| 89 | static int v2_write_file_info(struct super_block *sb, int type) |
| 90 | { |
| 91 | struct v2_disk_dqinfo dinfo; |
| 92 | struct mem_dqinfo *info = sb_dqopt(sb)->info+type; |
| 93 | ssize_t size; |
| 94 | |
| 95 | spin_lock(&dq_data_lock); |
| 96 | info->dqi_flags &= ~DQF_INFO_DIRTY; |
| 97 | dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace); |
| 98 | dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace); |
| 99 | dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK); |
| 100 | spin_unlock(&dq_data_lock); |
| 101 | dinfo.dqi_blocks = cpu_to_le32(info->u.v2_i.dqi_blocks); |
| 102 | dinfo.dqi_free_blk = cpu_to_le32(info->u.v2_i.dqi_free_blk); |
| 103 | dinfo.dqi_free_entry = cpu_to_le32(info->u.v2_i.dqi_free_entry); |
| 104 | size = sb->s_op->quota_write(sb, type, (char *)&dinfo, |
| 105 | sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF); |
| 106 | if (size != sizeof(struct v2_disk_dqinfo)) { |
| 107 | printk(KERN_WARNING "Can't write info structure on device %s.\n", |
| 108 | sb->s_id); |
| 109 | return -1; |
| 110 | } |
| 111 | return 0; |
| 112 | } |
| 113 | |
| 114 | static void disk2memdqb(struct mem_dqblk *m, struct v2_disk_dqblk *d) |
| 115 | { |
| 116 | m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit); |
| 117 | m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit); |
| 118 | m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes); |
| 119 | m->dqb_itime = le64_to_cpu(d->dqb_itime); |
Jan Kara | 1209546 | 2008-08-20 14:45:12 +0200 | [diff] [blame] | 120 | m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit)); |
| 121 | m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | m->dqb_curspace = le64_to_cpu(d->dqb_curspace); |
| 123 | m->dqb_btime = le64_to_cpu(d->dqb_btime); |
| 124 | } |
| 125 | |
| 126 | static void mem2diskdqb(struct v2_disk_dqblk *d, struct mem_dqblk *m, qid_t id) |
| 127 | { |
| 128 | d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit); |
| 129 | d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit); |
| 130 | d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes); |
| 131 | d->dqb_itime = cpu_to_le64(m->dqb_itime); |
Jan Kara | 1209546 | 2008-08-20 14:45:12 +0200 | [diff] [blame] | 132 | d->dqb_bhardlimit = cpu_to_le32(v2_qbtos(m->dqb_bhardlimit)); |
| 133 | d->dqb_bsoftlimit = cpu_to_le32(v2_qbtos(m->dqb_bsoftlimit)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | d->dqb_curspace = cpu_to_le64(m->dqb_curspace); |
| 135 | d->dqb_btime = cpu_to_le64(m->dqb_btime); |
| 136 | d->dqb_id = cpu_to_le32(id); |
| 137 | } |
| 138 | |
| 139 | static dqbuf_t getdqbuf(void) |
| 140 | { |
| 141 | dqbuf_t buf = kmalloc(V2_DQBLKSIZE, GFP_NOFS); |
| 142 | if (!buf) |
| 143 | printk(KERN_WARNING "VFS: Not enough memory for quota buffers.\n"); |
| 144 | return buf; |
| 145 | } |
| 146 | |
| 147 | static inline void freedqbuf(dqbuf_t buf) |
| 148 | { |
| 149 | kfree(buf); |
| 150 | } |
| 151 | |
| 152 | static inline ssize_t read_blk(struct super_block *sb, int type, uint blk, dqbuf_t buf) |
| 153 | { |
| 154 | memset(buf, 0, V2_DQBLKSIZE); |
| 155 | return sb->s_op->quota_read(sb, type, (char *)buf, |
| 156 | V2_DQBLKSIZE, blk << V2_DQBLKSIZE_BITS); |
| 157 | } |
| 158 | |
| 159 | static inline ssize_t write_blk(struct super_block *sb, int type, uint blk, dqbuf_t buf) |
| 160 | { |
| 161 | return sb->s_op->quota_write(sb, type, (char *)buf, |
| 162 | V2_DQBLKSIZE, blk << V2_DQBLKSIZE_BITS); |
| 163 | } |
| 164 | |
| 165 | /* Remove empty block from list and return it */ |
| 166 | static int get_free_dqblk(struct super_block *sb, int type) |
| 167 | { |
| 168 | dqbuf_t buf = getdqbuf(); |
| 169 | struct mem_dqinfo *info = sb_dqinfo(sb, type); |
| 170 | struct v2_disk_dqdbheader *dh = (struct v2_disk_dqdbheader *)buf; |
| 171 | int ret, blk; |
| 172 | |
| 173 | if (!buf) |
| 174 | return -ENOMEM; |
| 175 | if (info->u.v2_i.dqi_free_blk) { |
| 176 | blk = info->u.v2_i.dqi_free_blk; |
| 177 | if ((ret = read_blk(sb, type, blk, buf)) < 0) |
| 178 | goto out_buf; |
| 179 | info->u.v2_i.dqi_free_blk = le32_to_cpu(dh->dqdh_next_free); |
| 180 | } |
| 181 | else { |
| 182 | memset(buf, 0, V2_DQBLKSIZE); |
| 183 | /* Assure block allocation... */ |
| 184 | if ((ret = write_blk(sb, type, info->u.v2_i.dqi_blocks, buf)) < 0) |
| 185 | goto out_buf; |
| 186 | blk = info->u.v2_i.dqi_blocks++; |
| 187 | } |
| 188 | mark_info_dirty(sb, type); |
| 189 | ret = blk; |
| 190 | out_buf: |
| 191 | freedqbuf(buf); |
| 192 | return ret; |
| 193 | } |
| 194 | |
| 195 | /* Insert empty block to the list */ |
| 196 | static int put_free_dqblk(struct super_block *sb, int type, dqbuf_t buf, uint blk) |
| 197 | { |
| 198 | struct mem_dqinfo *info = sb_dqinfo(sb, type); |
| 199 | struct v2_disk_dqdbheader *dh = (struct v2_disk_dqdbheader *)buf; |
| 200 | int err; |
| 201 | |
| 202 | dh->dqdh_next_free = cpu_to_le32(info->u.v2_i.dqi_free_blk); |
| 203 | dh->dqdh_prev_free = cpu_to_le32(0); |
| 204 | dh->dqdh_entries = cpu_to_le16(0); |
| 205 | info->u.v2_i.dqi_free_blk = blk; |
| 206 | mark_info_dirty(sb, type); |
| 207 | /* Some strange block. We had better leave it... */ |
| 208 | if ((err = write_blk(sb, type, blk, buf)) < 0) |
| 209 | return err; |
| 210 | return 0; |
| 211 | } |
| 212 | |
| 213 | /* Remove given block from the list of blocks with free entries */ |
| 214 | static int remove_free_dqentry(struct super_block *sb, int type, dqbuf_t buf, uint blk) |
| 215 | { |
| 216 | dqbuf_t tmpbuf = getdqbuf(); |
| 217 | struct mem_dqinfo *info = sb_dqinfo(sb, type); |
| 218 | struct v2_disk_dqdbheader *dh = (struct v2_disk_dqdbheader *)buf; |
| 219 | uint nextblk = le32_to_cpu(dh->dqdh_next_free), prevblk = le32_to_cpu(dh->dqdh_prev_free); |
| 220 | int err; |
| 221 | |
| 222 | if (!tmpbuf) |
| 223 | return -ENOMEM; |
| 224 | if (nextblk) { |
| 225 | if ((err = read_blk(sb, type, nextblk, tmpbuf)) < 0) |
| 226 | goto out_buf; |
| 227 | ((struct v2_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = dh->dqdh_prev_free; |
| 228 | if ((err = write_blk(sb, type, nextblk, tmpbuf)) < 0) |
| 229 | goto out_buf; |
| 230 | } |
| 231 | if (prevblk) { |
| 232 | if ((err = read_blk(sb, type, prevblk, tmpbuf)) < 0) |
| 233 | goto out_buf; |
| 234 | ((struct v2_disk_dqdbheader *)tmpbuf)->dqdh_next_free = dh->dqdh_next_free; |
| 235 | if ((err = write_blk(sb, type, prevblk, tmpbuf)) < 0) |
| 236 | goto out_buf; |
| 237 | } |
| 238 | else { |
| 239 | info->u.v2_i.dqi_free_entry = nextblk; |
| 240 | mark_info_dirty(sb, type); |
| 241 | } |
| 242 | freedqbuf(tmpbuf); |
| 243 | dh->dqdh_next_free = dh->dqdh_prev_free = cpu_to_le32(0); |
| 244 | /* No matter whether write succeeds block is out of list */ |
| 245 | if (write_blk(sb, type, blk, buf) < 0) |
| 246 | printk(KERN_ERR "VFS: Can't write block (%u) with free entries.\n", blk); |
| 247 | return 0; |
| 248 | out_buf: |
| 249 | freedqbuf(tmpbuf); |
| 250 | return err; |
| 251 | } |
| 252 | |
| 253 | /* Insert given block to the beginning of list with free entries */ |
| 254 | static int insert_free_dqentry(struct super_block *sb, int type, dqbuf_t buf, uint blk) |
| 255 | { |
| 256 | dqbuf_t tmpbuf = getdqbuf(); |
| 257 | struct mem_dqinfo *info = sb_dqinfo(sb, type); |
| 258 | struct v2_disk_dqdbheader *dh = (struct v2_disk_dqdbheader *)buf; |
| 259 | int err; |
| 260 | |
| 261 | if (!tmpbuf) |
| 262 | return -ENOMEM; |
| 263 | dh->dqdh_next_free = cpu_to_le32(info->u.v2_i.dqi_free_entry); |
| 264 | dh->dqdh_prev_free = cpu_to_le32(0); |
| 265 | if ((err = write_blk(sb, type, blk, buf)) < 0) |
| 266 | goto out_buf; |
| 267 | if (info->u.v2_i.dqi_free_entry) { |
| 268 | if ((err = read_blk(sb, type, info->u.v2_i.dqi_free_entry, tmpbuf)) < 0) |
| 269 | goto out_buf; |
| 270 | ((struct v2_disk_dqdbheader *)tmpbuf)->dqdh_prev_free = cpu_to_le32(blk); |
| 271 | if ((err = write_blk(sb, type, info->u.v2_i.dqi_free_entry, tmpbuf)) < 0) |
| 272 | goto out_buf; |
| 273 | } |
| 274 | freedqbuf(tmpbuf); |
| 275 | info->u.v2_i.dqi_free_entry = blk; |
| 276 | mark_info_dirty(sb, type); |
| 277 | return 0; |
| 278 | out_buf: |
| 279 | freedqbuf(tmpbuf); |
| 280 | return err; |
| 281 | } |
| 282 | |
| 283 | /* Find space for dquot */ |
| 284 | static uint find_free_dqentry(struct dquot *dquot, int *err) |
| 285 | { |
| 286 | struct super_block *sb = dquot->dq_sb; |
| 287 | struct mem_dqinfo *info = sb_dqopt(sb)->info+dquot->dq_type; |
| 288 | uint blk, i; |
| 289 | struct v2_disk_dqdbheader *dh; |
| 290 | struct v2_disk_dqblk *ddquot; |
| 291 | struct v2_disk_dqblk fakedquot; |
| 292 | dqbuf_t buf; |
| 293 | |
| 294 | *err = 0; |
| 295 | if (!(buf = getdqbuf())) { |
| 296 | *err = -ENOMEM; |
| 297 | return 0; |
| 298 | } |
| 299 | dh = (struct v2_disk_dqdbheader *)buf; |
| 300 | ddquot = GETENTRIES(buf); |
| 301 | if (info->u.v2_i.dqi_free_entry) { |
| 302 | blk = info->u.v2_i.dqi_free_entry; |
| 303 | if ((*err = read_blk(sb, dquot->dq_type, blk, buf)) < 0) |
| 304 | goto out_buf; |
| 305 | } |
| 306 | else { |
| 307 | blk = get_free_dqblk(sb, dquot->dq_type); |
| 308 | if ((int)blk < 0) { |
| 309 | *err = blk; |
| 310 | freedqbuf(buf); |
| 311 | return 0; |
| 312 | } |
| 313 | memset(buf, 0, V2_DQBLKSIZE); |
| 314 | /* This is enough as block is already zeroed and entry list is empty... */ |
| 315 | info->u.v2_i.dqi_free_entry = blk; |
| 316 | mark_info_dirty(sb, dquot->dq_type); |
| 317 | } |
| 318 | if (le16_to_cpu(dh->dqdh_entries)+1 >= V2_DQSTRINBLK) /* Block will be full? */ |
| 319 | if ((*err = remove_free_dqentry(sb, dquot->dq_type, buf, blk)) < 0) { |
| 320 | printk(KERN_ERR "VFS: find_free_dqentry(): Can't remove block (%u) from entry free list.\n", blk); |
| 321 | goto out_buf; |
| 322 | } |
Marcin Slusarz | e3592b1 | 2008-04-30 00:54:48 -0700 | [diff] [blame] | 323 | le16_add_cpu(&dh->dqdh_entries, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | memset(&fakedquot, 0, sizeof(struct v2_disk_dqblk)); |
| 325 | /* Find free structure in block */ |
| 326 | for (i = 0; i < V2_DQSTRINBLK && memcmp(&fakedquot, ddquot+i, sizeof(struct v2_disk_dqblk)); i++); |
| 327 | #ifdef __QUOTA_V2_PARANOIA |
| 328 | if (i == V2_DQSTRINBLK) { |
| 329 | printk(KERN_ERR "VFS: find_free_dqentry(): Data block full but it shouldn't.\n"); |
| 330 | *err = -EIO; |
| 331 | goto out_buf; |
| 332 | } |
| 333 | #endif |
| 334 | if ((*err = write_blk(sb, dquot->dq_type, blk, buf)) < 0) { |
| 335 | printk(KERN_ERR "VFS: find_free_dqentry(): Can't write quota data block %u.\n", blk); |
| 336 | goto out_buf; |
| 337 | } |
| 338 | dquot->dq_off = (blk<<V2_DQBLKSIZE_BITS)+sizeof(struct v2_disk_dqdbheader)+i*sizeof(struct v2_disk_dqblk); |
| 339 | freedqbuf(buf); |
| 340 | return blk; |
| 341 | out_buf: |
| 342 | freedqbuf(buf); |
| 343 | return 0; |
| 344 | } |
| 345 | |
| 346 | /* Insert reference to structure into the trie */ |
| 347 | static int do_insert_tree(struct dquot *dquot, uint *treeblk, int depth) |
| 348 | { |
| 349 | struct super_block *sb = dquot->dq_sb; |
| 350 | dqbuf_t buf; |
| 351 | int ret = 0, newson = 0, newact = 0; |
| 352 | __le32 *ref; |
| 353 | uint newblk; |
| 354 | |
| 355 | if (!(buf = getdqbuf())) |
| 356 | return -ENOMEM; |
| 357 | if (!*treeblk) { |
| 358 | ret = get_free_dqblk(sb, dquot->dq_type); |
| 359 | if (ret < 0) |
| 360 | goto out_buf; |
| 361 | *treeblk = ret; |
| 362 | memset(buf, 0, V2_DQBLKSIZE); |
| 363 | newact = 1; |
| 364 | } |
| 365 | else { |
| 366 | if ((ret = read_blk(sb, dquot->dq_type, *treeblk, buf)) < 0) { |
| 367 | printk(KERN_ERR "VFS: Can't read tree quota block %u.\n", *treeblk); |
| 368 | goto out_buf; |
| 369 | } |
| 370 | } |
| 371 | ref = (__le32 *)buf; |
| 372 | newblk = le32_to_cpu(ref[GETIDINDEX(dquot->dq_id, depth)]); |
| 373 | if (!newblk) |
| 374 | newson = 1; |
| 375 | if (depth == V2_DQTREEDEPTH-1) { |
| 376 | #ifdef __QUOTA_V2_PARANOIA |
| 377 | if (newblk) { |
| 378 | printk(KERN_ERR "VFS: Inserting already present quota entry (block %u).\n", le32_to_cpu(ref[GETIDINDEX(dquot->dq_id, depth)])); |
| 379 | ret = -EIO; |
| 380 | goto out_buf; |
| 381 | } |
| 382 | #endif |
| 383 | newblk = find_free_dqentry(dquot, &ret); |
| 384 | } |
| 385 | else |
| 386 | ret = do_insert_tree(dquot, &newblk, depth+1); |
| 387 | if (newson && ret >= 0) { |
| 388 | ref[GETIDINDEX(dquot->dq_id, depth)] = cpu_to_le32(newblk); |
| 389 | ret = write_blk(sb, dquot->dq_type, *treeblk, buf); |
| 390 | } |
| 391 | else if (newact && ret < 0) |
| 392 | put_free_dqblk(sb, dquot->dq_type, buf, *treeblk); |
| 393 | out_buf: |
| 394 | freedqbuf(buf); |
| 395 | return ret; |
| 396 | } |
| 397 | |
| 398 | /* Wrapper for inserting quota structure into tree */ |
| 399 | static inline int dq_insert_tree(struct dquot *dquot) |
| 400 | { |
| 401 | int tmp = V2_DQTREEOFF; |
| 402 | return do_insert_tree(dquot, &tmp, 0); |
| 403 | } |
| 404 | |
| 405 | /* |
| 406 | * We don't have to be afraid of deadlocks as we never have quotas on quota files... |
| 407 | */ |
| 408 | static int v2_write_dquot(struct dquot *dquot) |
| 409 | { |
| 410 | int type = dquot->dq_type; |
| 411 | ssize_t ret; |
| 412 | struct v2_disk_dqblk ddquot, empty; |
| 413 | |
Ingo Molnar | d3be915 | 2006-03-23 03:00:29 -0800 | [diff] [blame] | 414 | /* dq_off is guarded by dqio_mutex */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | if (!dquot->dq_off) |
| 416 | if ((ret = dq_insert_tree(dquot)) < 0) { |
| 417 | printk(KERN_ERR "VFS: Error %zd occurred while creating quota.\n", ret); |
| 418 | return ret; |
| 419 | } |
| 420 | spin_lock(&dq_data_lock); |
| 421 | mem2diskdqb(&ddquot, &dquot->dq_dqb, dquot->dq_id); |
| 422 | /* Argh... We may need to write structure full of zeroes but that would be |
| 423 | * treated as an empty place by the rest of the code. Format change would |
| 424 | * be definitely cleaner but the problems probably are not worth it */ |
| 425 | memset(&empty, 0, sizeof(struct v2_disk_dqblk)); |
| 426 | if (!memcmp(&empty, &ddquot, sizeof(struct v2_disk_dqblk))) |
| 427 | ddquot.dqb_itime = cpu_to_le64(1); |
| 428 | spin_unlock(&dq_data_lock); |
| 429 | ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type, |
| 430 | (char *)&ddquot, sizeof(struct v2_disk_dqblk), dquot->dq_off); |
| 431 | if (ret != sizeof(struct v2_disk_dqblk)) { |
| 432 | printk(KERN_WARNING "VFS: dquota write failed on dev %s\n", dquot->dq_sb->s_id); |
| 433 | if (ret >= 0) |
| 434 | ret = -ENOSPC; |
| 435 | } |
| 436 | else |
| 437 | ret = 0; |
| 438 | dqstats.writes++; |
| 439 | |
| 440 | return ret; |
| 441 | } |
| 442 | |
| 443 | /* Free dquot entry in data block */ |
| 444 | static int free_dqentry(struct dquot *dquot, uint blk) |
| 445 | { |
| 446 | struct super_block *sb = dquot->dq_sb; |
| 447 | int type = dquot->dq_type; |
| 448 | struct v2_disk_dqdbheader *dh; |
| 449 | dqbuf_t buf = getdqbuf(); |
| 450 | int ret = 0; |
| 451 | |
| 452 | if (!buf) |
| 453 | return -ENOMEM; |
| 454 | if (dquot->dq_off >> V2_DQBLKSIZE_BITS != blk) { |
| 455 | printk(KERN_ERR "VFS: Quota structure has offset to other " |
| 456 | "block (%u) than it should (%u).\n", blk, |
| 457 | (uint)(dquot->dq_off >> V2_DQBLKSIZE_BITS)); |
| 458 | goto out_buf; |
| 459 | } |
| 460 | if ((ret = read_blk(sb, type, blk, buf)) < 0) { |
| 461 | printk(KERN_ERR "VFS: Can't read quota data block %u\n", blk); |
| 462 | goto out_buf; |
| 463 | } |
| 464 | dh = (struct v2_disk_dqdbheader *)buf; |
Marcin Slusarz | e3592b1 | 2008-04-30 00:54:48 -0700 | [diff] [blame] | 465 | le16_add_cpu(&dh->dqdh_entries, -1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | if (!le16_to_cpu(dh->dqdh_entries)) { /* Block got free? */ |
| 467 | if ((ret = remove_free_dqentry(sb, type, buf, blk)) < 0 || |
| 468 | (ret = put_free_dqblk(sb, type, buf, blk)) < 0) { |
| 469 | printk(KERN_ERR "VFS: Can't move quota data block (%u) " |
| 470 | "to free list.\n", blk); |
| 471 | goto out_buf; |
| 472 | } |
| 473 | } |
| 474 | else { |
| 475 | memset(buf+(dquot->dq_off & ((1 << V2_DQBLKSIZE_BITS)-1)), 0, |
| 476 | sizeof(struct v2_disk_dqblk)); |
| 477 | if (le16_to_cpu(dh->dqdh_entries) == V2_DQSTRINBLK-1) { |
| 478 | /* Insert will write block itself */ |
| 479 | if ((ret = insert_free_dqentry(sb, type, buf, blk)) < 0) { |
| 480 | printk(KERN_ERR "VFS: Can't insert quota data block (%u) to free entry list.\n", blk); |
| 481 | goto out_buf; |
| 482 | } |
| 483 | } |
| 484 | else |
| 485 | if ((ret = write_blk(sb, type, blk, buf)) < 0) { |
| 486 | printk(KERN_ERR "VFS: Can't write quota data " |
| 487 | "block %u\n", blk); |
| 488 | goto out_buf; |
| 489 | } |
| 490 | } |
| 491 | dquot->dq_off = 0; /* Quota is now unattached */ |
| 492 | out_buf: |
| 493 | freedqbuf(buf); |
| 494 | return ret; |
| 495 | } |
| 496 | |
| 497 | /* Remove reference to dquot from tree */ |
| 498 | static int remove_tree(struct dquot *dquot, uint *blk, int depth) |
| 499 | { |
| 500 | struct super_block *sb = dquot->dq_sb; |
| 501 | int type = dquot->dq_type; |
| 502 | dqbuf_t buf = getdqbuf(); |
| 503 | int ret = 0; |
| 504 | uint newblk; |
| 505 | __le32 *ref = (__le32 *)buf; |
| 506 | |
| 507 | if (!buf) |
| 508 | return -ENOMEM; |
| 509 | if ((ret = read_blk(sb, type, *blk, buf)) < 0) { |
| 510 | printk(KERN_ERR "VFS: Can't read quota data block %u\n", *blk); |
| 511 | goto out_buf; |
| 512 | } |
| 513 | newblk = le32_to_cpu(ref[GETIDINDEX(dquot->dq_id, depth)]); |
| 514 | if (depth == V2_DQTREEDEPTH-1) { |
| 515 | ret = free_dqentry(dquot, newblk); |
| 516 | newblk = 0; |
| 517 | } |
| 518 | else |
| 519 | ret = remove_tree(dquot, &newblk, depth+1); |
| 520 | if (ret >= 0 && !newblk) { |
| 521 | int i; |
| 522 | ref[GETIDINDEX(dquot->dq_id, depth)] = cpu_to_le32(0); |
| 523 | for (i = 0; i < V2_DQBLKSIZE && !buf[i]; i++); /* Block got empty? */ |
Niu YaWei | e821d94 | 2005-04-16 15:25:47 -0700 | [diff] [blame] | 524 | /* Don't put the root block into the free block list */ |
| 525 | if (i == V2_DQBLKSIZE && *blk != V2_DQTREEOFF) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | put_free_dqblk(sb, type, buf, *blk); |
| 527 | *blk = 0; |
| 528 | } |
| 529 | else |
| 530 | if ((ret = write_blk(sb, type, *blk, buf)) < 0) |
| 531 | printk(KERN_ERR "VFS: Can't write quota tree " |
| 532 | "block %u.\n", *blk); |
| 533 | } |
| 534 | out_buf: |
| 535 | freedqbuf(buf); |
| 536 | return ret; |
| 537 | } |
| 538 | |
| 539 | /* Delete dquot from tree */ |
| 540 | static int v2_delete_dquot(struct dquot *dquot) |
| 541 | { |
| 542 | uint tmp = V2_DQTREEOFF; |
| 543 | |
| 544 | if (!dquot->dq_off) /* Even not allocated? */ |
| 545 | return 0; |
| 546 | return remove_tree(dquot, &tmp, 0); |
| 547 | } |
| 548 | |
| 549 | /* Find entry in block */ |
| 550 | static loff_t find_block_dqentry(struct dquot *dquot, uint blk) |
| 551 | { |
| 552 | dqbuf_t buf = getdqbuf(); |
| 553 | loff_t ret = 0; |
| 554 | int i; |
| 555 | struct v2_disk_dqblk *ddquot = GETENTRIES(buf); |
| 556 | |
| 557 | if (!buf) |
| 558 | return -ENOMEM; |
| 559 | if ((ret = read_blk(dquot->dq_sb, dquot->dq_type, blk, buf)) < 0) { |
| 560 | printk(KERN_ERR "VFS: Can't read quota tree block %u.\n", blk); |
| 561 | goto out_buf; |
| 562 | } |
| 563 | if (dquot->dq_id) |
| 564 | for (i = 0; i < V2_DQSTRINBLK && |
| 565 | le32_to_cpu(ddquot[i].dqb_id) != dquot->dq_id; i++); |
| 566 | else { /* ID 0 as a bit more complicated searching... */ |
| 567 | struct v2_disk_dqblk fakedquot; |
| 568 | |
| 569 | memset(&fakedquot, 0, sizeof(struct v2_disk_dqblk)); |
| 570 | for (i = 0; i < V2_DQSTRINBLK; i++) |
| 571 | if (!le32_to_cpu(ddquot[i].dqb_id) && |
| 572 | memcmp(&fakedquot, ddquot+i, sizeof(struct v2_disk_dqblk))) |
| 573 | break; |
| 574 | } |
| 575 | if (i == V2_DQSTRINBLK) { |
| 576 | printk(KERN_ERR "VFS: Quota for id %u referenced " |
| 577 | "but not present.\n", dquot->dq_id); |
| 578 | ret = -EIO; |
| 579 | goto out_buf; |
| 580 | } |
| 581 | else |
| 582 | ret = (blk << V2_DQBLKSIZE_BITS) + sizeof(struct |
| 583 | v2_disk_dqdbheader) + i * sizeof(struct v2_disk_dqblk); |
| 584 | out_buf: |
| 585 | freedqbuf(buf); |
| 586 | return ret; |
| 587 | } |
| 588 | |
| 589 | /* Find entry for given id in the tree */ |
| 590 | static loff_t find_tree_dqentry(struct dquot *dquot, uint blk, int depth) |
| 591 | { |
| 592 | dqbuf_t buf = getdqbuf(); |
| 593 | loff_t ret = 0; |
| 594 | __le32 *ref = (__le32 *)buf; |
| 595 | |
| 596 | if (!buf) |
| 597 | return -ENOMEM; |
| 598 | if ((ret = read_blk(dquot->dq_sb, dquot->dq_type, blk, buf)) < 0) { |
| 599 | printk(KERN_ERR "VFS: Can't read quota tree block %u.\n", blk); |
| 600 | goto out_buf; |
| 601 | } |
| 602 | ret = 0; |
| 603 | blk = le32_to_cpu(ref[GETIDINDEX(dquot->dq_id, depth)]); |
| 604 | if (!blk) /* No reference? */ |
| 605 | goto out_buf; |
| 606 | if (depth < V2_DQTREEDEPTH-1) |
| 607 | ret = find_tree_dqentry(dquot, blk, depth+1); |
| 608 | else |
| 609 | ret = find_block_dqentry(dquot, blk); |
| 610 | out_buf: |
| 611 | freedqbuf(buf); |
| 612 | return ret; |
| 613 | } |
| 614 | |
| 615 | /* Find entry for given id in the tree - wrapper function */ |
| 616 | static inline loff_t find_dqentry(struct dquot *dquot) |
| 617 | { |
| 618 | return find_tree_dqentry(dquot, V2_DQTREEOFF, 0); |
| 619 | } |
| 620 | |
| 621 | static int v2_read_dquot(struct dquot *dquot) |
| 622 | { |
| 623 | int type = dquot->dq_type; |
| 624 | loff_t offset; |
| 625 | struct v2_disk_dqblk ddquot, empty; |
| 626 | int ret = 0; |
| 627 | |
| 628 | #ifdef __QUOTA_V2_PARANOIA |
| 629 | /* Invalidated quota? */ |
| 630 | if (!dquot->dq_sb || !sb_dqopt(dquot->dq_sb)->files[type]) { |
| 631 | printk(KERN_ERR "VFS: Quota invalidated while reading!\n"); |
| 632 | return -EIO; |
| 633 | } |
| 634 | #endif |
| 635 | offset = find_dqentry(dquot); |
| 636 | if (offset <= 0) { /* Entry not present? */ |
| 637 | if (offset < 0) |
| 638 | printk(KERN_ERR "VFS: Can't read quota " |
| 639 | "structure for id %u.\n", dquot->dq_id); |
| 640 | dquot->dq_off = 0; |
| 641 | set_bit(DQ_FAKE_B, &dquot->dq_flags); |
| 642 | memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk)); |
| 643 | ret = offset; |
| 644 | } |
| 645 | else { |
| 646 | dquot->dq_off = offset; |
| 647 | if ((ret = dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, |
| 648 | (char *)&ddquot, sizeof(struct v2_disk_dqblk), offset)) |
| 649 | != sizeof(struct v2_disk_dqblk)) { |
| 650 | if (ret >= 0) |
| 651 | ret = -EIO; |
| 652 | printk(KERN_ERR "VFS: Error while reading quota " |
| 653 | "structure for id %u.\n", dquot->dq_id); |
| 654 | memset(&ddquot, 0, sizeof(struct v2_disk_dqblk)); |
| 655 | } |
| 656 | else { |
| 657 | ret = 0; |
| 658 | /* We need to escape back all-zero structure */ |
| 659 | memset(&empty, 0, sizeof(struct v2_disk_dqblk)); |
| 660 | empty.dqb_itime = cpu_to_le64(1); |
| 661 | if (!memcmp(&empty, &ddquot, sizeof(struct v2_disk_dqblk))) |
| 662 | ddquot.dqb_itime = 0; |
| 663 | } |
| 664 | disk2memdqb(&dquot->dq_dqb, &ddquot); |
| 665 | if (!dquot->dq_dqb.dqb_bhardlimit && |
| 666 | !dquot->dq_dqb.dqb_bsoftlimit && |
| 667 | !dquot->dq_dqb.dqb_ihardlimit && |
| 668 | !dquot->dq_dqb.dqb_isoftlimit) |
| 669 | set_bit(DQ_FAKE_B, &dquot->dq_flags); |
| 670 | } |
| 671 | dqstats.reads++; |
| 672 | |
| 673 | return ret; |
| 674 | } |
| 675 | |
| 676 | /* Check whether dquot should not be deleted. We know we are |
| 677 | * the only one operating on dquot (thanks to dq_lock) */ |
| 678 | static int v2_release_dquot(struct dquot *dquot) |
| 679 | { |
| 680 | if (test_bit(DQ_FAKE_B, &dquot->dq_flags) && !(dquot->dq_dqb.dqb_curinodes | dquot->dq_dqb.dqb_curspace)) |
| 681 | return v2_delete_dquot(dquot); |
| 682 | return 0; |
| 683 | } |
| 684 | |
| 685 | static struct quota_format_ops v2_format_ops = { |
| 686 | .check_quota_file = v2_check_quota_file, |
| 687 | .read_file_info = v2_read_file_info, |
| 688 | .write_file_info = v2_write_file_info, |
| 689 | .free_file_info = NULL, |
| 690 | .read_dqblk = v2_read_dquot, |
| 691 | .commit_dqblk = v2_write_dquot, |
| 692 | .release_dqblk = v2_release_dquot, |
| 693 | }; |
| 694 | |
| 695 | static struct quota_format_type v2_quota_format = { |
| 696 | .qf_fmt_id = QFMT_VFS_V0, |
| 697 | .qf_ops = &v2_format_ops, |
| 698 | .qf_owner = THIS_MODULE |
| 699 | }; |
| 700 | |
| 701 | static int __init init_v2_quota_format(void) |
| 702 | { |
| 703 | return register_quota_format(&v2_quota_format); |
| 704 | } |
| 705 | |
| 706 | static void __exit exit_v2_quota_format(void) |
| 707 | { |
| 708 | unregister_quota_format(&v2_quota_format); |
| 709 | } |
| 710 | |
| 711 | module_init(init_v2_quota_format); |
| 712 | module_exit(exit_v2_quota_format); |