Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 1 | /* |
| 2 | * sufile.c - NILFS segment usage file. |
| 3 | * |
| 4 | * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | * |
| 20 | * Written by Koji Sato <koji@osrg.net>. |
Ryusuke Konishi | dda54f4 | 2009-05-16 21:49:10 +0900 | [diff] [blame] | 21 | * Rivised by Ryusuke Konishi <ryusuke@osrg.net>. |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 22 | */ |
| 23 | |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/fs.h> |
| 26 | #include <linux/string.h> |
| 27 | #include <linux/buffer_head.h> |
| 28 | #include <linux/errno.h> |
| 29 | #include <linux/nilfs2_fs.h> |
| 30 | #include "mdt.h" |
| 31 | #include "sufile.h" |
| 32 | |
| 33 | |
| 34 | static inline unsigned long |
| 35 | nilfs_sufile_segment_usages_per_block(const struct inode *sufile) |
| 36 | { |
| 37 | return NILFS_MDT(sufile)->mi_entries_per_block; |
| 38 | } |
| 39 | |
| 40 | static unsigned long |
| 41 | nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum) |
| 42 | { |
| 43 | __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset; |
| 44 | do_div(t, nilfs_sufile_segment_usages_per_block(sufile)); |
| 45 | return (unsigned long)t; |
| 46 | } |
| 47 | |
| 48 | static unsigned long |
| 49 | nilfs_sufile_get_offset(const struct inode *sufile, __u64 segnum) |
| 50 | { |
| 51 | __u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset; |
| 52 | return do_div(t, nilfs_sufile_segment_usages_per_block(sufile)); |
| 53 | } |
| 54 | |
| 55 | static unsigned long |
| 56 | nilfs_sufile_segment_usages_in_block(const struct inode *sufile, __u64 curr, |
| 57 | __u64 max) |
| 58 | { |
| 59 | return min_t(unsigned long, |
| 60 | nilfs_sufile_segment_usages_per_block(sufile) - |
| 61 | nilfs_sufile_get_offset(sufile, curr), |
| 62 | max - curr + 1); |
| 63 | } |
| 64 | |
| 65 | static inline struct nilfs_sufile_header * |
| 66 | nilfs_sufile_block_get_header(const struct inode *sufile, |
| 67 | struct buffer_head *bh, |
| 68 | void *kaddr) |
| 69 | { |
| 70 | return kaddr + bh_offset(bh); |
| 71 | } |
| 72 | |
| 73 | static struct nilfs_segment_usage * |
| 74 | nilfs_sufile_block_get_segment_usage(const struct inode *sufile, __u64 segnum, |
| 75 | struct buffer_head *bh, void *kaddr) |
| 76 | { |
| 77 | return kaddr + bh_offset(bh) + |
| 78 | nilfs_sufile_get_offset(sufile, segnum) * |
| 79 | NILFS_MDT(sufile)->mi_entry_size; |
| 80 | } |
| 81 | |
| 82 | static inline int nilfs_sufile_get_header_block(struct inode *sufile, |
| 83 | struct buffer_head **bhp) |
| 84 | { |
| 85 | return nilfs_mdt_get_block(sufile, 0, 0, NULL, bhp); |
| 86 | } |
| 87 | |
| 88 | static inline int |
| 89 | nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum, |
| 90 | int create, struct buffer_head **bhp) |
| 91 | { |
| 92 | return nilfs_mdt_get_block(sufile, |
| 93 | nilfs_sufile_get_blkoff(sufile, segnum), |
| 94 | create, NULL, bhp); |
| 95 | } |
| 96 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 97 | static void nilfs_sufile_mod_counter(struct buffer_head *header_bh, |
| 98 | u64 ncleanadd, u64 ndirtyadd) |
| 99 | { |
| 100 | struct nilfs_sufile_header *header; |
| 101 | void *kaddr; |
| 102 | |
| 103 | kaddr = kmap_atomic(header_bh->b_page, KM_USER0); |
| 104 | header = kaddr + bh_offset(header_bh); |
| 105 | le64_add_cpu(&header->sh_ncleansegs, ncleanadd); |
| 106 | le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd); |
| 107 | kunmap_atomic(kaddr, KM_USER0); |
| 108 | |
| 109 | nilfs_mdt_mark_buffer_dirty(header_bh); |
| 110 | } |
| 111 | |
Ryusuke Konishi | dda54f4 | 2009-05-16 21:49:10 +0900 | [diff] [blame] | 112 | /** |
| 113 | * nilfs_sufile_updatev - modify multiple segment usages at a time |
| 114 | * @sufile: inode of segment usage file |
| 115 | * @segnumv: array of segment numbers |
| 116 | * @nsegs: size of @segnumv array |
| 117 | * @create: creation flag |
| 118 | * @ndone: place to store number of modified segments on @segnumv |
| 119 | * @dofunc: primitive operation for the update |
| 120 | * |
| 121 | * Description: nilfs_sufile_updatev() repeatedly calls @dofunc |
| 122 | * against the given array of segments. The @dofunc is called with |
| 123 | * buffers of a header block and the sufile block in which the target |
| 124 | * segment usage entry is contained. If @ndone is given, the number |
| 125 | * of successfully modified segments from the head is stored in the |
| 126 | * place @ndone points to. |
| 127 | * |
| 128 | * Return Value: On success, zero is returned. On error, one of the |
| 129 | * following negative error codes is returned. |
| 130 | * |
| 131 | * %-EIO - I/O error. |
| 132 | * |
| 133 | * %-ENOMEM - Insufficient amount of memory available. |
| 134 | * |
| 135 | * %-ENOENT - Given segment usage is in hole block (may be returned if |
| 136 | * @create is zero) |
| 137 | * |
| 138 | * %-EINVAL - Invalid segment usage number |
| 139 | */ |
| 140 | int nilfs_sufile_updatev(struct inode *sufile, __u64 *segnumv, size_t nsegs, |
| 141 | int create, size_t *ndone, |
| 142 | void (*dofunc)(struct inode *, __u64, |
| 143 | struct buffer_head *, |
| 144 | struct buffer_head *)) |
| 145 | { |
| 146 | struct buffer_head *header_bh, *bh; |
| 147 | unsigned long blkoff, prev_blkoff; |
| 148 | __u64 *seg; |
| 149 | size_t nerr = 0, n = 0; |
| 150 | int ret = 0; |
| 151 | |
| 152 | if (unlikely(nsegs == 0)) |
| 153 | goto out; |
| 154 | |
| 155 | down_write(&NILFS_MDT(sufile)->mi_sem); |
| 156 | for (seg = segnumv; seg < segnumv + nsegs; seg++) { |
| 157 | if (unlikely(*seg >= nilfs_sufile_get_nsegments(sufile))) { |
| 158 | printk(KERN_WARNING |
| 159 | "%s: invalid segment number: %llu\n", __func__, |
| 160 | (unsigned long long)*seg); |
| 161 | nerr++; |
| 162 | } |
| 163 | } |
| 164 | if (nerr > 0) { |
| 165 | ret = -EINVAL; |
| 166 | goto out_sem; |
| 167 | } |
| 168 | |
| 169 | ret = nilfs_sufile_get_header_block(sufile, &header_bh); |
| 170 | if (ret < 0) |
| 171 | goto out_sem; |
| 172 | |
| 173 | seg = segnumv; |
| 174 | blkoff = nilfs_sufile_get_blkoff(sufile, *seg); |
| 175 | ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh); |
| 176 | if (ret < 0) |
| 177 | goto out_header; |
| 178 | |
| 179 | for (;;) { |
| 180 | dofunc(sufile, *seg, header_bh, bh); |
| 181 | |
| 182 | if (++seg >= segnumv + nsegs) |
| 183 | break; |
| 184 | prev_blkoff = blkoff; |
| 185 | blkoff = nilfs_sufile_get_blkoff(sufile, *seg); |
| 186 | if (blkoff == prev_blkoff) |
| 187 | continue; |
| 188 | |
| 189 | /* get different block */ |
| 190 | brelse(bh); |
| 191 | ret = nilfs_mdt_get_block(sufile, blkoff, create, NULL, &bh); |
| 192 | if (unlikely(ret < 0)) |
| 193 | goto out_header; |
| 194 | } |
| 195 | brelse(bh); |
| 196 | |
| 197 | out_header: |
| 198 | n = seg - segnumv; |
| 199 | brelse(header_bh); |
| 200 | out_sem: |
| 201 | up_write(&NILFS_MDT(sufile)->mi_sem); |
| 202 | out: |
| 203 | if (ndone) |
| 204 | *ndone = n; |
| 205 | return ret; |
| 206 | } |
| 207 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 208 | int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create, |
| 209 | void (*dofunc)(struct inode *, __u64, |
| 210 | struct buffer_head *, |
| 211 | struct buffer_head *)) |
| 212 | { |
| 213 | struct buffer_head *header_bh, *bh; |
| 214 | int ret; |
| 215 | |
| 216 | if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) { |
| 217 | printk(KERN_WARNING "%s: invalid segment number: %llu\n", |
| 218 | __func__, (unsigned long long)segnum); |
| 219 | return -EINVAL; |
| 220 | } |
| 221 | down_write(&NILFS_MDT(sufile)->mi_sem); |
| 222 | |
| 223 | ret = nilfs_sufile_get_header_block(sufile, &header_bh); |
| 224 | if (ret < 0) |
| 225 | goto out_sem; |
| 226 | |
| 227 | ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh); |
| 228 | if (!ret) { |
| 229 | dofunc(sufile, segnum, header_bh, bh); |
| 230 | brelse(bh); |
| 231 | } |
| 232 | brelse(header_bh); |
| 233 | |
| 234 | out_sem: |
| 235 | up_write(&NILFS_MDT(sufile)->mi_sem); |
| 236 | return ret; |
| 237 | } |
| 238 | |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 239 | /** |
| 240 | * nilfs_sufile_alloc - allocate a segment |
| 241 | * @sufile: inode of segment usage file |
| 242 | * @segnump: pointer to segment number |
| 243 | * |
| 244 | * Description: nilfs_sufile_alloc() allocates a clean segment. |
| 245 | * |
| 246 | * Return Value: On success, 0 is returned and the segment number of the |
| 247 | * allocated segment is stored in the place pointed by @segnump. On error, one |
| 248 | * of the following negative error codes is returned. |
| 249 | * |
| 250 | * %-EIO - I/O error. |
| 251 | * |
| 252 | * %-ENOMEM - Insufficient amount of memory available. |
| 253 | * |
| 254 | * %-ENOSPC - No clean segment left. |
| 255 | */ |
| 256 | int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump) |
| 257 | { |
| 258 | struct buffer_head *header_bh, *su_bh; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 259 | struct nilfs_sufile_header *header; |
| 260 | struct nilfs_segment_usage *su; |
| 261 | size_t susz = NILFS_MDT(sufile)->mi_entry_size; |
| 262 | __u64 segnum, maxsegnum, last_alloc; |
| 263 | void *kaddr; |
| 264 | unsigned long nsegments, ncleansegs, nsus; |
| 265 | int ret, i, j; |
| 266 | |
| 267 | down_write(&NILFS_MDT(sufile)->mi_sem); |
| 268 | |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 269 | ret = nilfs_sufile_get_header_block(sufile, &header_bh); |
| 270 | if (ret < 0) |
| 271 | goto out_sem; |
| 272 | kaddr = kmap_atomic(header_bh->b_page, KM_USER0); |
| 273 | header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr); |
| 274 | ncleansegs = le64_to_cpu(header->sh_ncleansegs); |
| 275 | last_alloc = le64_to_cpu(header->sh_last_alloc); |
| 276 | kunmap_atomic(kaddr, KM_USER0); |
| 277 | |
| 278 | nsegments = nilfs_sufile_get_nsegments(sufile); |
| 279 | segnum = last_alloc + 1; |
| 280 | maxsegnum = nsegments - 1; |
| 281 | for (i = 0; i < nsegments; i += nsus) { |
| 282 | if (segnum >= nsegments) { |
| 283 | /* wrap around */ |
| 284 | segnum = 0; |
| 285 | maxsegnum = last_alloc; |
| 286 | } |
| 287 | ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1, |
| 288 | &su_bh); |
| 289 | if (ret < 0) |
| 290 | goto out_header; |
| 291 | kaddr = kmap_atomic(su_bh->b_page, KM_USER0); |
| 292 | su = nilfs_sufile_block_get_segment_usage( |
| 293 | sufile, segnum, su_bh, kaddr); |
| 294 | |
| 295 | nsus = nilfs_sufile_segment_usages_in_block( |
| 296 | sufile, segnum, maxsegnum); |
| 297 | for (j = 0; j < nsus; j++, su = (void *)su + susz, segnum++) { |
| 298 | if (!nilfs_segment_usage_clean(su)) |
| 299 | continue; |
| 300 | /* found a clean segment */ |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 301 | nilfs_segment_usage_set_dirty(su); |
| 302 | kunmap_atomic(kaddr, KM_USER0); |
| 303 | |
| 304 | kaddr = kmap_atomic(header_bh->b_page, KM_USER0); |
| 305 | header = nilfs_sufile_block_get_header( |
| 306 | sufile, header_bh, kaddr); |
| 307 | le64_add_cpu(&header->sh_ncleansegs, -1); |
| 308 | le64_add_cpu(&header->sh_ndirtysegs, 1); |
| 309 | header->sh_last_alloc = cpu_to_le64(segnum); |
| 310 | kunmap_atomic(kaddr, KM_USER0); |
| 311 | |
| 312 | nilfs_mdt_mark_buffer_dirty(header_bh); |
| 313 | nilfs_mdt_mark_buffer_dirty(su_bh); |
| 314 | nilfs_mdt_mark_dirty(sufile); |
| 315 | brelse(su_bh); |
| 316 | *segnump = segnum; |
| 317 | goto out_header; |
| 318 | } |
| 319 | |
| 320 | kunmap_atomic(kaddr, KM_USER0); |
| 321 | brelse(su_bh); |
| 322 | } |
| 323 | |
| 324 | /* no segments left */ |
| 325 | ret = -ENOSPC; |
| 326 | |
| 327 | out_header: |
| 328 | brelse(header_bh); |
| 329 | |
| 330 | out_sem: |
| 331 | up_write(&NILFS_MDT(sufile)->mi_sem); |
| 332 | return ret; |
| 333 | } |
| 334 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 335 | void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum, |
| 336 | struct buffer_head *header_bh, |
| 337 | struct buffer_head *su_bh) |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 338 | { |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 339 | struct nilfs_segment_usage *su; |
| 340 | void *kaddr; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 341 | |
| 342 | kaddr = kmap_atomic(su_bh->b_page, KM_USER0); |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 343 | su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); |
Ryusuke Konishi | 1f5abe7 | 2009-04-06 19:01:55 -0700 | [diff] [blame] | 344 | if (unlikely(!nilfs_segment_usage_clean(su))) { |
| 345 | printk(KERN_WARNING "%s: segment %llu must be clean\n", |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 346 | __func__, (unsigned long long)segnum); |
Ryusuke Konishi | 1f5abe7 | 2009-04-06 19:01:55 -0700 | [diff] [blame] | 347 | kunmap_atomic(kaddr, KM_USER0); |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 348 | return; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 349 | } |
| 350 | nilfs_segment_usage_set_dirty(su); |
| 351 | kunmap_atomic(kaddr, KM_USER0); |
| 352 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 353 | nilfs_sufile_mod_counter(header_bh, -1, 1); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 354 | nilfs_mdt_mark_buffer_dirty(su_bh); |
| 355 | nilfs_mdt_mark_dirty(sufile); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 356 | } |
| 357 | |
Ryusuke Konishi | c85399c | 2009-04-05 18:30:58 +0900 | [diff] [blame] | 358 | void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum, |
| 359 | struct buffer_head *header_bh, |
| 360 | struct buffer_head *su_bh) |
| 361 | { |
| 362 | struct nilfs_segment_usage *su; |
| 363 | void *kaddr; |
| 364 | int clean, dirty; |
| 365 | |
| 366 | kaddr = kmap_atomic(su_bh->b_page, KM_USER0); |
| 367 | su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); |
| 368 | if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) && |
| 369 | su->su_nblocks == cpu_to_le32(0)) { |
| 370 | kunmap_atomic(kaddr, KM_USER0); |
| 371 | return; |
| 372 | } |
| 373 | clean = nilfs_segment_usage_clean(su); |
| 374 | dirty = nilfs_segment_usage_dirty(su); |
| 375 | |
| 376 | /* make the segment garbage */ |
| 377 | su->su_lastmod = cpu_to_le64(0); |
| 378 | su->su_nblocks = cpu_to_le32(0); |
| 379 | su->su_flags = cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY); |
| 380 | kunmap_atomic(kaddr, KM_USER0); |
| 381 | |
| 382 | nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1); |
| 383 | nilfs_mdt_mark_buffer_dirty(su_bh); |
| 384 | nilfs_mdt_mark_dirty(sufile); |
| 385 | } |
| 386 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 387 | void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum, |
| 388 | struct buffer_head *header_bh, |
| 389 | struct buffer_head *su_bh) |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 390 | { |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 391 | struct nilfs_segment_usage *su; |
| 392 | void *kaddr; |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 393 | int sudirty; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 394 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 395 | kaddr = kmap_atomic(su_bh->b_page, KM_USER0); |
| 396 | su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); |
| 397 | if (nilfs_segment_usage_clean(su)) { |
| 398 | printk(KERN_WARNING "%s: segment %llu is already clean\n", |
| 399 | __func__, (unsigned long long)segnum); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 400 | kunmap_atomic(kaddr, KM_USER0); |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 401 | return; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 402 | } |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 403 | WARN_ON(nilfs_segment_usage_error(su)); |
| 404 | WARN_ON(!nilfs_segment_usage_dirty(su)); |
| 405 | |
| 406 | sudirty = nilfs_segment_usage_dirty(su); |
| 407 | nilfs_segment_usage_set_clean(su); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 408 | kunmap_atomic(kaddr, KM_USER0); |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 409 | nilfs_mdt_mark_buffer_dirty(su_bh); |
| 410 | |
| 411 | nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 412 | nilfs_mdt_mark_dirty(sufile); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 413 | } |
| 414 | |
| 415 | /** |
| 416 | * nilfs_sufile_get_segment_usage - get a segment usage |
| 417 | * @sufile: inode of segment usage file |
| 418 | * @segnum: segment number |
| 419 | * @sup: pointer to segment usage |
| 420 | * @bhp: pointer to buffer head |
| 421 | * |
| 422 | * Description: nilfs_sufile_get_segment_usage() acquires the segment usage |
| 423 | * specified by @segnum. |
| 424 | * |
| 425 | * Return Value: On success, 0 is returned, and the segment usage and the |
| 426 | * buffer head of the buffer on which the segment usage is located are stored |
| 427 | * in the place pointed by @sup and @bhp, respectively. On error, one of the |
| 428 | * following negative error codes is returned. |
| 429 | * |
| 430 | * %-EIO - I/O error. |
| 431 | * |
| 432 | * %-ENOMEM - Insufficient amount of memory available. |
| 433 | * |
| 434 | * %-EINVAL - Invalid segment usage number. |
| 435 | */ |
| 436 | int nilfs_sufile_get_segment_usage(struct inode *sufile, __u64 segnum, |
| 437 | struct nilfs_segment_usage **sup, |
| 438 | struct buffer_head **bhp) |
| 439 | { |
| 440 | struct buffer_head *bh; |
| 441 | struct nilfs_segment_usage *su; |
| 442 | void *kaddr; |
| 443 | int ret; |
| 444 | |
| 445 | /* segnum is 0 origin */ |
Ryusuke Konishi | 1f5abe7 | 2009-04-06 19:01:55 -0700 | [diff] [blame] | 446 | if (segnum >= nilfs_sufile_get_nsegments(sufile)) |
| 447 | return -EINVAL; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 448 | down_write(&NILFS_MDT(sufile)->mi_sem); |
| 449 | ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 1, &bh); |
| 450 | if (ret < 0) |
| 451 | goto out_sem; |
| 452 | kaddr = kmap(bh->b_page); |
| 453 | su = nilfs_sufile_block_get_segment_usage(sufile, segnum, bh, kaddr); |
| 454 | if (nilfs_segment_usage_error(su)) { |
| 455 | kunmap(bh->b_page); |
| 456 | brelse(bh); |
| 457 | ret = -EINVAL; |
| 458 | goto out_sem; |
| 459 | } |
| 460 | |
| 461 | if (sup != NULL) |
| 462 | *sup = su; |
| 463 | *bhp = bh; |
| 464 | |
| 465 | out_sem: |
| 466 | up_write(&NILFS_MDT(sufile)->mi_sem); |
| 467 | return ret; |
| 468 | } |
| 469 | |
| 470 | /** |
| 471 | * nilfs_sufile_put_segment_usage - put a segment usage |
| 472 | * @sufile: inode of segment usage file |
| 473 | * @segnum: segment number |
| 474 | * @bh: buffer head |
| 475 | * |
| 476 | * Description: nilfs_sufile_put_segment_usage() releases the segment usage |
| 477 | * specified by @segnum. @bh must be the buffer head which have been returned |
| 478 | * by a previous call to nilfs_sufile_get_segment_usage() with @segnum. |
| 479 | */ |
| 480 | void nilfs_sufile_put_segment_usage(struct inode *sufile, __u64 segnum, |
| 481 | struct buffer_head *bh) |
| 482 | { |
| 483 | kunmap(bh->b_page); |
| 484 | brelse(bh); |
| 485 | } |
| 486 | |
| 487 | /** |
| 488 | * nilfs_sufile_get_stat - get segment usage statistics |
| 489 | * @sufile: inode of segment usage file |
| 490 | * @stat: pointer to a structure of segment usage statistics |
| 491 | * |
| 492 | * Description: nilfs_sufile_get_stat() returns information about segment |
| 493 | * usage. |
| 494 | * |
| 495 | * Return Value: On success, 0 is returned, and segment usage information is |
| 496 | * stored in the place pointed by @stat. On error, one of the following |
| 497 | * negative error codes is returned. |
| 498 | * |
| 499 | * %-EIO - I/O error. |
| 500 | * |
| 501 | * %-ENOMEM - Insufficient amount of memory available. |
| 502 | */ |
| 503 | int nilfs_sufile_get_stat(struct inode *sufile, struct nilfs_sustat *sustat) |
| 504 | { |
| 505 | struct buffer_head *header_bh; |
| 506 | struct nilfs_sufile_header *header; |
Ryusuke Konishi | 2c2e52f | 2009-04-06 19:01:54 -0700 | [diff] [blame] | 507 | struct the_nilfs *nilfs = NILFS_MDT(sufile)->mi_nilfs; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 508 | void *kaddr; |
| 509 | int ret; |
| 510 | |
| 511 | down_read(&NILFS_MDT(sufile)->mi_sem); |
| 512 | |
| 513 | ret = nilfs_sufile_get_header_block(sufile, &header_bh); |
| 514 | if (ret < 0) |
| 515 | goto out_sem; |
| 516 | |
| 517 | kaddr = kmap_atomic(header_bh->b_page, KM_USER0); |
| 518 | header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr); |
| 519 | sustat->ss_nsegs = nilfs_sufile_get_nsegments(sufile); |
| 520 | sustat->ss_ncleansegs = le64_to_cpu(header->sh_ncleansegs); |
| 521 | sustat->ss_ndirtysegs = le64_to_cpu(header->sh_ndirtysegs); |
Ryusuke Konishi | 2c2e52f | 2009-04-06 19:01:54 -0700 | [diff] [blame] | 522 | sustat->ss_ctime = nilfs->ns_ctime; |
| 523 | sustat->ss_nongc_ctime = nilfs->ns_nongc_ctime; |
| 524 | spin_lock(&nilfs->ns_last_segment_lock); |
| 525 | sustat->ss_prot_seq = nilfs->ns_prot_seq; |
| 526 | spin_unlock(&nilfs->ns_last_segment_lock); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 527 | kunmap_atomic(kaddr, KM_USER0); |
| 528 | brelse(header_bh); |
| 529 | |
| 530 | out_sem: |
| 531 | up_read(&NILFS_MDT(sufile)->mi_sem); |
| 532 | return ret; |
| 533 | } |
| 534 | |
| 535 | /** |
| 536 | * nilfs_sufile_get_ncleansegs - get the number of clean segments |
| 537 | * @sufile: inode of segment usage file |
| 538 | * @nsegsp: pointer to the number of clean segments |
| 539 | * |
| 540 | * Description: nilfs_sufile_get_ncleansegs() acquires the number of clean |
| 541 | * segments. |
| 542 | * |
| 543 | * Return Value: On success, 0 is returned and the number of clean segments is |
| 544 | * stored in the place pointed by @nsegsp. On error, one of the following |
| 545 | * negative error codes is returned. |
| 546 | * |
| 547 | * %-EIO - I/O error. |
| 548 | * |
| 549 | * %-ENOMEM - Insufficient amount of memory available. |
| 550 | */ |
| 551 | int nilfs_sufile_get_ncleansegs(struct inode *sufile, unsigned long *nsegsp) |
| 552 | { |
| 553 | struct nilfs_sustat sustat; |
| 554 | int ret; |
| 555 | |
| 556 | ret = nilfs_sufile_get_stat(sufile, &sustat); |
| 557 | if (ret == 0) |
| 558 | *nsegsp = sustat.ss_ncleansegs; |
| 559 | return ret; |
| 560 | } |
| 561 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 562 | void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum, |
| 563 | struct buffer_head *header_bh, |
| 564 | struct buffer_head *su_bh) |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 565 | { |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 566 | struct nilfs_segment_usage *su; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 567 | void *kaddr; |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 568 | int suclean; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 569 | |
| 570 | kaddr = kmap_atomic(su_bh->b_page, KM_USER0); |
| 571 | su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr); |
| 572 | if (nilfs_segment_usage_error(su)) { |
| 573 | kunmap_atomic(kaddr, KM_USER0); |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 574 | return; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 575 | } |
Ryusuke Konishi | 88072fa | 2009-04-05 15:03:16 +0900 | [diff] [blame] | 576 | suclean = nilfs_segment_usage_clean(su); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 577 | nilfs_segment_usage_set_error(su); |
| 578 | kunmap_atomic(kaddr, KM_USER0); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 579 | |
Ryusuke Konishi | a703018 | 2009-04-05 18:24:11 +0900 | [diff] [blame] | 580 | if (suclean) |
| 581 | nilfs_sufile_mod_counter(header_bh, -1, 0); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 582 | nilfs_mdt_mark_buffer_dirty(su_bh); |
| 583 | nilfs_mdt_mark_dirty(sufile); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 584 | } |
| 585 | |
| 586 | /** |
| 587 | * nilfs_sufile_get_suinfo - |
| 588 | * @sufile: inode of segment usage file |
| 589 | * @segnum: segment number to start looking |
| 590 | * @si: array of suinfo |
| 591 | * @nsi: size of suinfo array |
| 592 | * |
| 593 | * Description: |
| 594 | * |
| 595 | * Return Value: On success, 0 is returned and .... On error, one of the |
| 596 | * following negative error codes is returned. |
| 597 | * |
| 598 | * %-EIO - I/O error. |
| 599 | * |
| 600 | * %-ENOMEM - Insufficient amount of memory available. |
| 601 | */ |
| 602 | ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, |
| 603 | struct nilfs_suinfo *si, size_t nsi) |
| 604 | { |
| 605 | struct buffer_head *su_bh; |
| 606 | struct nilfs_segment_usage *su; |
| 607 | size_t susz = NILFS_MDT(sufile)->mi_entry_size; |
Ryusuke Konishi | cece552 | 2009-04-06 19:01:58 -0700 | [diff] [blame] | 608 | struct the_nilfs *nilfs = NILFS_MDT(sufile)->mi_nilfs; |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 609 | void *kaddr; |
| 610 | unsigned long nsegs, segusages_per_block; |
| 611 | ssize_t n; |
| 612 | int ret, i, j; |
| 613 | |
| 614 | down_read(&NILFS_MDT(sufile)->mi_sem); |
| 615 | |
| 616 | segusages_per_block = nilfs_sufile_segment_usages_per_block(sufile); |
| 617 | nsegs = min_t(unsigned long, |
| 618 | nilfs_sufile_get_nsegments(sufile) - segnum, |
| 619 | nsi); |
| 620 | for (i = 0; i < nsegs; i += n, segnum += n) { |
| 621 | n = min_t(unsigned long, |
| 622 | segusages_per_block - |
| 623 | nilfs_sufile_get_offset(sufile, segnum), |
| 624 | nsegs - i); |
| 625 | ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, |
| 626 | &su_bh); |
| 627 | if (ret < 0) { |
| 628 | if (ret != -ENOENT) |
| 629 | goto out; |
| 630 | /* hole */ |
| 631 | memset(&si[i], 0, sizeof(struct nilfs_suinfo) * n); |
| 632 | continue; |
| 633 | } |
| 634 | |
| 635 | kaddr = kmap_atomic(su_bh->b_page, KM_USER0); |
| 636 | su = nilfs_sufile_block_get_segment_usage( |
| 637 | sufile, segnum, su_bh, kaddr); |
| 638 | for (j = 0; j < n; j++, su = (void *)su + susz) { |
| 639 | si[i + j].sui_lastmod = le64_to_cpu(su->su_lastmod); |
| 640 | si[i + j].sui_nblocks = le32_to_cpu(su->su_nblocks); |
Ryusuke Konishi | cece552 | 2009-04-06 19:01:58 -0700 | [diff] [blame] | 641 | si[i + j].sui_flags = le32_to_cpu(su->su_flags) & |
| 642 | ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE); |
Ryusuke Konishi | 3efb55b | 2009-03-30 00:50:19 +0900 | [diff] [blame] | 643 | if (nilfs_segment_is_active(nilfs, segnum + j)) |
Ryusuke Konishi | cece552 | 2009-04-06 19:01:58 -0700 | [diff] [blame] | 644 | si[i + j].sui_flags |= |
| 645 | (1UL << NILFS_SEGMENT_USAGE_ACTIVE); |
Koji Sato | 6c98cd4 | 2009-04-06 19:01:32 -0700 | [diff] [blame] | 646 | } |
| 647 | kunmap_atomic(kaddr, KM_USER0); |
| 648 | brelse(su_bh); |
| 649 | } |
| 650 | ret = nsegs; |
| 651 | |
| 652 | out: |
| 653 | up_read(&NILFS_MDT(sufile)->mi_sem); |
| 654 | return ret; |
| 655 | } |