1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright © 2001-2007 Red Hat, Inc. 5 * 6 * Created by David Woodhouse <dwmw2@infradead.org> 7 * 8 * For licensing information, see the file 'LICENCE' in this directory. 9 * 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/mtd/mtd.h> 14 #include <linux/slab.h> 15 #include <linux/pagemap.h> 16 #include <linux/crc32.h> 17 #include <linux/compiler.h> 18 #include <linux/stat.h> 19 #include "nodelist.h" 20 #include "compr.h" 21 22 static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c, 23 struct jffs2_inode_cache *ic, 24 struct jffs2_raw_node_ref *raw); 25 static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 26 struct jffs2_inode_info *f, struct jffs2_full_dnode *fd); 27 static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 28 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd); 29 static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 30 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd); 31 static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 32 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 33 uint32_t start, uint32_t end); 34 static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 35 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 36 uint32_t start, uint32_t end); 37 static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 38 struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f); 39 40 /* Called with erase_completion_lock held */ 41 static struct jffs2_eraseblock *jffs2_find_gc_block(struct jffs2_sb_info *c) 42 { 43 struct jffs2_eraseblock *ret; 44 struct list_head *nextlist = NULL; 45 int n = jiffies % 128; 46 47 /* Pick an eraseblock to garbage collect next. This is where we'll 48 put the clever wear-levelling algorithms. Eventually. */ 49 /* We possibly want to favour the dirtier blocks more when the 50 number of free blocks is low. */ 51 again: 52 if (!list_empty(&c->bad_used_list) && c->nr_free_blocks > c->resv_blocks_gcbad) { 53 D1(printk(KERN_DEBUG "Picking block from bad_used_list to GC next\n")); 54 nextlist = &c->bad_used_list; 55 } else if (n < 50 && !list_empty(&c->erasable_list)) { 56 /* Note that most of them will have gone directly to be erased. 57 So don't favour the erasable_list _too_ much. */ 58 D1(printk(KERN_DEBUG "Picking block from erasable_list to GC next\n")); 59 nextlist = &c->erasable_list; 60 } else if (n < 110 && !list_empty(&c->very_dirty_list)) { 61 /* Most of the time, pick one off the very_dirty list */ 62 D1(printk(KERN_DEBUG "Picking block from very_dirty_list to GC next\n")); 63 nextlist = &c->very_dirty_list; 64 } else if (n < 126 && !list_empty(&c->dirty_list)) { 65 D1(printk(KERN_DEBUG "Picking block from dirty_list to GC next\n")); 66 nextlist = &c->dirty_list; 67 } else if (!list_empty(&c->clean_list)) { 68 D1(printk(KERN_DEBUG "Picking block from clean_list to GC next\n")); 69 nextlist = &c->clean_list; 70 } else if (!list_empty(&c->dirty_list)) { 71 D1(printk(KERN_DEBUG "Picking block from dirty_list to GC next (clean_list was empty)\n")); 72 73 nextlist = &c->dirty_list; 74 } else if (!list_empty(&c->very_dirty_list)) { 75 D1(printk(KERN_DEBUG "Picking block from very_dirty_list to GC next (clean_list and dirty_list were empty)\n")); 76 nextlist = &c->very_dirty_list; 77 } else if (!list_empty(&c->erasable_list)) { 78 D1(printk(KERN_DEBUG "Picking block from erasable_list to GC next (clean_list and {very_,}dirty_list were empty)\n")); 79 80 nextlist = &c->erasable_list; 81 } else if (!list_empty(&c->erasable_pending_wbuf_list)) { 82 /* There are blocks are wating for the wbuf sync */ 83 D1(printk(KERN_DEBUG "Synching wbuf in order to reuse erasable_pending_wbuf_list blocks\n")); 84 spin_unlock(&c->erase_completion_lock); 85 jffs2_flush_wbuf_pad(c); 86 spin_lock(&c->erase_completion_lock); 87 goto again; 88 } else { 89 /* Eep. All were empty */ 90 D1(printk(KERN_NOTICE "jffs2: No clean, dirty _or_ erasable blocks to GC from! Where are they all?\n")); 91 return NULL; 92 } 93 94 ret = list_entry(nextlist->next, struct jffs2_eraseblock, list); 95 list_del(&ret->list); 96 c->gcblock = ret; 97 ret->gc_node = ret->first_node; 98 if (!ret->gc_node) { 99 printk(KERN_WARNING "Eep. ret->gc_node for block at 0x%08x is NULL\n", ret->offset); 100 BUG(); 101 } 102 103 /* Have we accidentally picked a clean block with wasted space ? */ 104 if (ret->wasted_size) { 105 D1(printk(KERN_DEBUG "Converting wasted_size %08x to dirty_size\n", ret->wasted_size)); 106 ret->dirty_size += ret->wasted_size; 107 c->wasted_size -= ret->wasted_size; 108 c->dirty_size += ret->wasted_size; 109 ret->wasted_size = 0; 110 } 111 112 return ret; 113 } 114 115 /* jffs2_garbage_collect_pass 116 * Make a single attempt to progress GC. Move one node, and possibly 117 * start erasing one eraseblock. 118 */ 119 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c) 120 { 121 struct jffs2_inode_info *f; 122 struct jffs2_inode_cache *ic; 123 struct jffs2_eraseblock *jeb; 124 struct jffs2_raw_node_ref *raw; 125 uint32_t gcblock_dirty; 126 int ret = 0, inum, nlink; 127 int xattr = 0; 128 129 if (mutex_lock_interruptible(&c->alloc_sem)) 130 return -EINTR; 131 132 for (;;) { 133 spin_lock(&c->erase_completion_lock); 134 if (!c->unchecked_size) 135 break; 136 137 /* We can't start doing GC yet. We haven't finished checking 138 the node CRCs etc. Do it now. */ 139 140 /* checked_ino is protected by the alloc_sem */ 141 if (c->checked_ino > c->highest_ino && xattr) { 142 printk(KERN_CRIT "Checked all inodes but still 0x%x bytes of unchecked space?\n", 143 c->unchecked_size); 144 jffs2_dbg_dump_block_lists_nolock(c); 145 spin_unlock(&c->erase_completion_lock); 146 mutex_unlock(&c->alloc_sem); 147 return -ENOSPC; 148 } 149 150 spin_unlock(&c->erase_completion_lock); 151 152 if (!xattr) 153 xattr = jffs2_verify_xattr(c); 154 155 spin_lock(&c->inocache_lock); 156 157 ic = jffs2_get_ino_cache(c, c->checked_ino++); 158 159 if (!ic) { 160 spin_unlock(&c->inocache_lock); 161 continue; 162 } 163 164 if (!ic->pino_nlink) { 165 D1(printk(KERN_DEBUG "Skipping check of ino #%d with nlink/pino zero\n", 166 ic->ino)); 167 spin_unlock(&c->inocache_lock); 168 jffs2_xattr_delete_inode(c, ic); 169 continue; 170 } 171 switch(ic->state) { 172 case INO_STATE_CHECKEDABSENT: 173 case INO_STATE_PRESENT: 174 D1(printk(KERN_DEBUG "Skipping ino #%u already checked\n", ic->ino)); 175 spin_unlock(&c->inocache_lock); 176 continue; 177 178 case INO_STATE_GC: 179 case INO_STATE_CHECKING: 180 printk(KERN_WARNING "Inode #%u is in state %d during CRC check phase!\n", ic->ino, ic->state); 181 spin_unlock(&c->inocache_lock); 182 BUG(); 183 184 case INO_STATE_READING: 185 /* We need to wait for it to finish, lest we move on 186 and trigger the BUG() above while we haven't yet 187 finished checking all its nodes */ 188 D1(printk(KERN_DEBUG "Waiting for ino #%u to finish reading\n", ic->ino)); 189 /* We need to come back again for the _same_ inode. We've 190 made no progress in this case, but that should be OK */ 191 c->checked_ino--; 192 193 mutex_unlock(&c->alloc_sem); 194 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); 195 return 0; 196 197 default: 198 BUG(); 199 200 case INO_STATE_UNCHECKED: 201 ; 202 } 203 ic->state = INO_STATE_CHECKING; 204 spin_unlock(&c->inocache_lock); 205 206 D1(printk(KERN_DEBUG "jffs2_garbage_collect_pass() triggering inode scan of ino#%u\n", ic->ino)); 207 208 ret = jffs2_do_crccheck_inode(c, ic); 209 if (ret) 210 printk(KERN_WARNING "Returned error for crccheck of ino #%u. Expect badness...\n", ic->ino); 211 212 jffs2_set_inocache_state(c, ic, INO_STATE_CHECKEDABSENT); 213 mutex_unlock(&c->alloc_sem); 214 return ret; 215 } 216 217 /* First, work out which block we're garbage-collecting */ 218 jeb = c->gcblock; 219 220 if (!jeb) 221 jeb = jffs2_find_gc_block(c); 222 223 if (!jeb) { 224 /* Couldn't find a free block. But maybe we can just erase one and make 'progress'? */ 225 if (!list_empty(&c->erase_pending_list)) { 226 spin_unlock(&c->erase_completion_lock); 227 mutex_unlock(&c->alloc_sem); 228 return -EAGAIN; 229 } 230 D1(printk(KERN_NOTICE "jffs2: Couldn't find erase block to garbage collect!\n")); 231 spin_unlock(&c->erase_completion_lock); 232 mutex_unlock(&c->alloc_sem); 233 return -EIO; 234 } 235 236 D1(printk(KERN_DEBUG "GC from block %08x, used_size %08x, dirty_size %08x, free_size %08x\n", jeb->offset, jeb->used_size, jeb->dirty_size, jeb->free_size)); 237 D1(if (c->nextblock) 238 printk(KERN_DEBUG "Nextblock at %08x, used_size %08x, dirty_size %08x, wasted_size %08x, free_size %08x\n", c->nextblock->offset, c->nextblock->used_size, c->nextblock->dirty_size, c->nextblock->wasted_size, c->nextblock->free_size)); 239 240 if (!jeb->used_size) { 241 mutex_unlock(&c->alloc_sem); 242 goto eraseit; 243 } 244 245 raw = jeb->gc_node; 246 gcblock_dirty = jeb->dirty_size; 247 248 while(ref_obsolete(raw)) { 249 D1(printk(KERN_DEBUG "Node at 0x%08x is obsolete... skipping\n", ref_offset(raw))); 250 raw = ref_next(raw); 251 if (unlikely(!raw)) { 252 printk(KERN_WARNING "eep. End of raw list while still supposedly nodes to GC\n"); 253 printk(KERN_WARNING "erase block at 0x%08x. free_size 0x%08x, dirty_size 0x%08x, used_size 0x%08x\n", 254 jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size); 255 jeb->gc_node = raw; 256 spin_unlock(&c->erase_completion_lock); 257 mutex_unlock(&c->alloc_sem); 258 BUG(); 259 } 260 } 261 jeb->gc_node = raw; 262 263 D1(printk(KERN_DEBUG "Going to garbage collect node at 0x%08x\n", ref_offset(raw))); 264 265 if (!raw->next_in_ino) { 266 /* Inode-less node. Clean marker, snapshot or something like that */ 267 spin_unlock(&c->erase_completion_lock); 268 if (ref_flags(raw) == REF_PRISTINE) { 269 /* It's an unknown node with JFFS2_FEATURE_RWCOMPAT_COPY */ 270 jffs2_garbage_collect_pristine(c, NULL, raw); 271 } else { 272 /* Just mark it obsolete */ 273 jffs2_mark_node_obsolete(c, raw); 274 } 275 mutex_unlock(&c->alloc_sem); 276 goto eraseit_lock; 277 } 278 279 ic = jffs2_raw_ref_to_ic(raw); 280 281 #ifdef CONFIG_JFFS2_FS_XATTR 282 /* When 'ic' refers xattr_datum/xattr_ref, this node is GCed as xattr. 283 * We can decide whether this node is inode or xattr by ic->class. */ 284 if (ic->class == RAWNODE_CLASS_XATTR_DATUM 285 || ic->class == RAWNODE_CLASS_XATTR_REF) { 286 spin_unlock(&c->erase_completion_lock); 287 288 if (ic->class == RAWNODE_CLASS_XATTR_DATUM) { 289 ret = jffs2_garbage_collect_xattr_datum(c, (struct jffs2_xattr_datum *)ic, raw); 290 } else { 291 ret = jffs2_garbage_collect_xattr_ref(c, (struct jffs2_xattr_ref *)ic, raw); 292 } 293 goto test_gcnode; 294 } 295 #endif 296 297 /* We need to hold the inocache. Either the erase_completion_lock or 298 the inocache_lock are sufficient; we trade down since the inocache_lock 299 causes less contention. */ 300 spin_lock(&c->inocache_lock); 301 302 spin_unlock(&c->erase_completion_lock); 303 304 D1(printk(KERN_DEBUG "jffs2_garbage_collect_pass collecting from block @0x%08x. Node @0x%08x(%d), ino #%u\n", jeb->offset, ref_offset(raw), ref_flags(raw), ic->ino)); 305 306 /* Three possibilities: 307 1. Inode is already in-core. We must iget it and do proper 308 updating to its fragtree, etc. 309 2. Inode is not in-core, node is REF_PRISTINE. We lock the 310 inocache to prevent a read_inode(), copy the node intact. 311 3. Inode is not in-core, node is not pristine. We must iget() 312 and take the slow path. 313 */ 314 315 switch(ic->state) { 316 case INO_STATE_CHECKEDABSENT: 317 /* It's been checked, but it's not currently in-core. 318 We can just copy any pristine nodes, but have 319 to prevent anyone else from doing read_inode() while 320 we're at it, so we set the state accordingly */ 321 if (ref_flags(raw) == REF_PRISTINE) 322 ic->state = INO_STATE_GC; 323 else { 324 D1(printk(KERN_DEBUG "Ino #%u is absent but node not REF_PRISTINE. Reading.\n", 325 ic->ino)); 326 } 327 break; 328 329 case INO_STATE_PRESENT: 330 /* It's in-core. GC must iget() it. */ 331 break; 332 333 case INO_STATE_UNCHECKED: 334 case INO_STATE_CHECKING: 335 case INO_STATE_GC: 336 /* Should never happen. We should have finished checking 337 by the time we actually start doing any GC, and since 338 we're holding the alloc_sem, no other garbage collection 339 can happen. 340 */ 341 printk(KERN_CRIT "Inode #%u already in state %d in jffs2_garbage_collect_pass()!\n", 342 ic->ino, ic->state); 343 mutex_unlock(&c->alloc_sem); 344 spin_unlock(&c->inocache_lock); 345 BUG(); 346 347 case INO_STATE_READING: 348 /* Someone's currently trying to read it. We must wait for 349 them to finish and then go through the full iget() route 350 to do the GC. However, sometimes read_inode() needs to get 351 the alloc_sem() (for marking nodes invalid) so we must 352 drop the alloc_sem before sleeping. */ 353 354 mutex_unlock(&c->alloc_sem); 355 D1(printk(KERN_DEBUG "jffs2_garbage_collect_pass() waiting for ino #%u in state %d\n", 356 ic->ino, ic->state)); 357 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); 358 /* And because we dropped the alloc_sem we must start again from the 359 beginning. Ponder chance of livelock here -- we're returning success 360 without actually making any progress. 361 362 Q: What are the chances that the inode is back in INO_STATE_READING 363 again by the time we next enter this function? And that this happens 364 enough times to cause a real delay? 365 366 A: Small enough that I don't care :) 367 */ 368 return 0; 369 } 370 371 /* OK. Now if the inode is in state INO_STATE_GC, we are going to copy the 372 node intact, and we don't have to muck about with the fragtree etc. 373 because we know it's not in-core. If it _was_ in-core, we go through 374 all the iget() crap anyway */ 375 376 if (ic->state == INO_STATE_GC) { 377 spin_unlock(&c->inocache_lock); 378 379 ret = jffs2_garbage_collect_pristine(c, ic, raw); 380 381 spin_lock(&c->inocache_lock); 382 ic->state = INO_STATE_CHECKEDABSENT; 383 wake_up(&c->inocache_wq); 384 385 if (ret != -EBADFD) { 386 spin_unlock(&c->inocache_lock); 387 goto test_gcnode; 388 } 389 390 /* Fall through if it wanted us to, with inocache_lock held */ 391 } 392 393 /* Prevent the fairly unlikely race where the gcblock is 394 entirely obsoleted by the final close of a file which had 395 the only valid nodes in the block, followed by erasure, 396 followed by freeing of the ic because the erased block(s) 397 held _all_ the nodes of that inode.... never been seen but 398 it's vaguely possible. */ 399 400 inum = ic->ino; 401 nlink = ic->pino_nlink; 402 spin_unlock(&c->inocache_lock); 403 404 f = jffs2_gc_fetch_inode(c, inum, !nlink); 405 if (IS_ERR(f)) { 406 ret = PTR_ERR(f); 407 goto release_sem; 408 } 409 if (!f) { 410 ret = 0; 411 goto release_sem; 412 } 413 414 ret = jffs2_garbage_collect_live(c, jeb, raw, f); 415 416 jffs2_gc_release_inode(c, f); 417 418 test_gcnode: 419 if (jeb->dirty_size == gcblock_dirty && !ref_obsolete(jeb->gc_node)) { 420 /* Eep. This really should never happen. GC is broken */ 421 printk(KERN_ERR "Error garbage collecting node at %08x!\n", ref_offset(jeb->gc_node)); 422 ret = -ENOSPC; 423 } 424 release_sem: 425 mutex_unlock(&c->alloc_sem); 426 427 eraseit_lock: 428 /* If we've finished this block, start it erasing */ 429 spin_lock(&c->erase_completion_lock); 430 431 eraseit: 432 if (c->gcblock && !c->gcblock->used_size) { 433 D1(printk(KERN_DEBUG "Block at 0x%08x completely obsoleted by GC. Moving to erase_pending_list\n", c->gcblock->offset)); 434 /* We're GC'ing an empty block? */ 435 list_add_tail(&c->gcblock->list, &c->erase_pending_list); 436 c->gcblock = NULL; 437 c->nr_erasing_blocks++; 438 jffs2_erase_pending_trigger(c); 439 } 440 spin_unlock(&c->erase_completion_lock); 441 442 return ret; 443 } 444 445 static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 446 struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f) 447 { 448 struct jffs2_node_frag *frag; 449 struct jffs2_full_dnode *fn = NULL; 450 struct jffs2_full_dirent *fd; 451 uint32_t start = 0, end = 0, nrfrags = 0; 452 int ret = 0; 453 454 mutex_lock(&f->sem); 455 456 /* Now we have the lock for this inode. Check that it's still the one at the head 457 of the list. */ 458 459 spin_lock(&c->erase_completion_lock); 460 461 if (c->gcblock != jeb) { 462 spin_unlock(&c->erase_completion_lock); 463 D1(printk(KERN_DEBUG "GC block is no longer gcblock. Restart\n")); 464 goto upnout; 465 } 466 if (ref_obsolete(raw)) { 467 spin_unlock(&c->erase_completion_lock); 468 D1(printk(KERN_DEBUG "node to be GC'd was obsoleted in the meantime.\n")); 469 /* They'll call again */ 470 goto upnout; 471 } 472 spin_unlock(&c->erase_completion_lock); 473 474 /* OK. Looks safe. And nobody can get us now because we have the semaphore. Move the block */ 475 if (f->metadata && f->metadata->raw == raw) { 476 fn = f->metadata; 477 ret = jffs2_garbage_collect_metadata(c, jeb, f, fn); 478 goto upnout; 479 } 480 481 /* FIXME. Read node and do lookup? */ 482 for (frag = frag_first(&f->fragtree); frag; frag = frag_next(frag)) { 483 if (frag->node && frag->node->raw == raw) { 484 fn = frag->node; 485 end = frag->ofs + frag->size; 486 if (!nrfrags++) 487 start = frag->ofs; 488 if (nrfrags == frag->node->frags) 489 break; /* We've found them all */ 490 } 491 } 492 if (fn) { 493 if (ref_flags(raw) == REF_PRISTINE) { 494 ret = jffs2_garbage_collect_pristine(c, f->inocache, raw); 495 if (!ret) { 496 /* Urgh. Return it sensibly. */ 497 frag->node->raw = f->inocache->nodes; 498 } 499 if (ret != -EBADFD) 500 goto upnout; 501 } 502 /* We found a datanode. Do the GC */ 503 if((start >> PAGE_CACHE_SHIFT) < ((end-1) >> PAGE_CACHE_SHIFT)) { 504 /* It crosses a page boundary. Therefore, it must be a hole. */ 505 ret = jffs2_garbage_collect_hole(c, jeb, f, fn, start, end); 506 } else { 507 /* It could still be a hole. But we GC the page this way anyway */ 508 ret = jffs2_garbage_collect_dnode(c, jeb, f, fn, start, end); 509 } 510 goto upnout; 511 } 512 513 /* Wasn't a dnode. Try dirent */ 514 for (fd = f->dents; fd; fd=fd->next) { 515 if (fd->raw == raw) 516 break; 517 } 518 519 if (fd && fd->ino) { 520 ret = jffs2_garbage_collect_dirent(c, jeb, f, fd); 521 } else if (fd) { 522 ret = jffs2_garbage_collect_deletion_dirent(c, jeb, f, fd); 523 } else { 524 printk(KERN_WARNING "Raw node at 0x%08x wasn't in node lists for ino #%u\n", 525 ref_offset(raw), f->inocache->ino); 526 if (ref_obsolete(raw)) { 527 printk(KERN_WARNING "But it's obsolete so we don't mind too much\n"); 528 } else { 529 jffs2_dbg_dump_node(c, ref_offset(raw)); 530 BUG(); 531 } 532 } 533 upnout: 534 mutex_unlock(&f->sem); 535 536 return ret; 537 } 538 539 static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c, 540 struct jffs2_inode_cache *ic, 541 struct jffs2_raw_node_ref *raw) 542 { 543 union jffs2_node_union *node; 544 size_t retlen; 545 int ret; 546 uint32_t phys_ofs, alloclen; 547 uint32_t crc, rawlen; 548 int retried = 0; 549 550 D1(printk(KERN_DEBUG "Going to GC REF_PRISTINE node at 0x%08x\n", ref_offset(raw))); 551 552 alloclen = rawlen = ref_totlen(c, c->gcblock, raw); 553 554 /* Ask for a small amount of space (or the totlen if smaller) because we 555 don't want to force wastage of the end of a block if splitting would 556 work. */ 557 if (ic && alloclen > sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN) 558 alloclen = sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN; 559 560 ret = jffs2_reserve_space_gc(c, alloclen, &alloclen, rawlen); 561 /* 'rawlen' is not the exact summary size; it is only an upper estimation */ 562 563 if (ret) 564 return ret; 565 566 if (alloclen < rawlen) { 567 /* Doesn't fit untouched. We'll go the old route and split it */ 568 return -EBADFD; 569 } 570 571 node = kmalloc(rawlen, GFP_KERNEL); 572 if (!node) 573 return -ENOMEM; 574 575 ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)node); 576 if (!ret && retlen != rawlen) 577 ret = -EIO; 578 if (ret) 579 goto out_node; 580 581 crc = crc32(0, node, sizeof(struct jffs2_unknown_node)-4); 582 if (je32_to_cpu(node->u.hdr_crc) != crc) { 583 printk(KERN_WARNING "Header CRC failed on REF_PRISTINE node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 584 ref_offset(raw), je32_to_cpu(node->u.hdr_crc), crc); 585 goto bail; 586 } 587 588 switch(je16_to_cpu(node->u.nodetype)) { 589 case JFFS2_NODETYPE_INODE: 590 crc = crc32(0, node, sizeof(node->i)-8); 591 if (je32_to_cpu(node->i.node_crc) != crc) { 592 printk(KERN_WARNING "Node CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 593 ref_offset(raw), je32_to_cpu(node->i.node_crc), crc); 594 goto bail; 595 } 596 597 if (je32_to_cpu(node->i.dsize)) { 598 crc = crc32(0, node->i.data, je32_to_cpu(node->i.csize)); 599 if (je32_to_cpu(node->i.data_crc) != crc) { 600 printk(KERN_WARNING "Data CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 601 ref_offset(raw), je32_to_cpu(node->i.data_crc), crc); 602 goto bail; 603 } 604 } 605 break; 606 607 case JFFS2_NODETYPE_DIRENT: 608 crc = crc32(0, node, sizeof(node->d)-8); 609 if (je32_to_cpu(node->d.node_crc) != crc) { 610 printk(KERN_WARNING "Node CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 611 ref_offset(raw), je32_to_cpu(node->d.node_crc), crc); 612 goto bail; 613 } 614 615 if (strnlen(node->d.name, node->d.nsize) != node->d.nsize) { 616 printk(KERN_WARNING "Name in dirent node at 0x%08x contains zeroes\n", ref_offset(raw)); 617 goto bail; 618 } 619 620 if (node->d.nsize) { 621 crc = crc32(0, node->d.name, node->d.nsize); 622 if (je32_to_cpu(node->d.name_crc) != crc) { 623 printk(KERN_WARNING "Name CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 624 ref_offset(raw), je32_to_cpu(node->d.name_crc), crc); 625 goto bail; 626 } 627 } 628 break; 629 default: 630 /* If it's inode-less, we don't _know_ what it is. Just copy it intact */ 631 if (ic) { 632 printk(KERN_WARNING "Unknown node type for REF_PRISTINE node at 0x%08x: 0x%04x\n", 633 ref_offset(raw), je16_to_cpu(node->u.nodetype)); 634 goto bail; 635 } 636 } 637 638 /* OK, all the CRCs are good; this node can just be copied as-is. */ 639 retry: 640 phys_ofs = write_ofs(c); 641 642 ret = jffs2_flash_write(c, phys_ofs, rawlen, &retlen, (char *)node); 643 644 if (ret || (retlen != rawlen)) { 645 printk(KERN_NOTICE "Write of %d bytes at 0x%08x failed. returned %d, retlen %zd\n", 646 rawlen, phys_ofs, ret, retlen); 647 if (retlen) { 648 jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, rawlen, NULL); 649 } else { 650 printk(KERN_NOTICE "Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n", phys_ofs); 651 } 652 if (!retried) { 653 /* Try to reallocate space and retry */ 654 uint32_t dummy; 655 struct jffs2_eraseblock *jeb = &c->blocks[phys_ofs / c->sector_size]; 656 657 retried = 1; 658 659 D1(printk(KERN_DEBUG "Retrying failed write of REF_PRISTINE node.\n")); 660 661 jffs2_dbg_acct_sanity_check(c,jeb); 662 jffs2_dbg_acct_paranoia_check(c, jeb); 663 664 ret = jffs2_reserve_space_gc(c, rawlen, &dummy, rawlen); 665 /* this is not the exact summary size of it, 666 it is only an upper estimation */ 667 668 if (!ret) { 669 D1(printk(KERN_DEBUG "Allocated space at 0x%08x to retry failed write.\n", phys_ofs)); 670 671 jffs2_dbg_acct_sanity_check(c,jeb); 672 jffs2_dbg_acct_paranoia_check(c, jeb); 673 674 goto retry; 675 } 676 D1(printk(KERN_DEBUG "Failed to allocate space to retry failed write: %d!\n", ret)); 677 } 678 679 if (!ret) 680 ret = -EIO; 681 goto out_node; 682 } 683 jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, rawlen, ic); 684 685 jffs2_mark_node_obsolete(c, raw); 686 D1(printk(KERN_DEBUG "WHEEE! GC REF_PRISTINE node at 0x%08x succeeded\n", ref_offset(raw))); 687 688 out_node: 689 kfree(node); 690 return ret; 691 bail: 692 ret = -EBADFD; 693 goto out_node; 694 } 695 696 static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 697 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn) 698 { 699 struct jffs2_full_dnode *new_fn; 700 struct jffs2_raw_inode ri; 701 struct jffs2_node_frag *last_frag; 702 union jffs2_device_node dev; 703 char *mdata = NULL, mdatalen = 0; 704 uint32_t alloclen, ilen; 705 int ret; 706 707 if (S_ISBLK(JFFS2_F_I_MODE(f)) || 708 S_ISCHR(JFFS2_F_I_MODE(f)) ) { 709 /* For these, we don't actually need to read the old node */ 710 mdatalen = jffs2_encode_dev(&dev, JFFS2_F_I_RDEV(f)); 711 mdata = (char *)&dev; 712 D1(printk(KERN_DEBUG "jffs2_garbage_collect_metadata(): Writing %d bytes of kdev_t\n", mdatalen)); 713 } else if (S_ISLNK(JFFS2_F_I_MODE(f))) { 714 mdatalen = fn->size; 715 mdata = kmalloc(fn->size, GFP_KERNEL); 716 if (!mdata) { 717 printk(KERN_WARNING "kmalloc of mdata failed in jffs2_garbage_collect_metadata()\n"); 718 return -ENOMEM; 719 } 720 ret = jffs2_read_dnode(c, f, fn, mdata, 0, mdatalen); 721 if (ret) { 722 printk(KERN_WARNING "read of old metadata failed in jffs2_garbage_collect_metadata(): %d\n", ret); 723 kfree(mdata); 724 return ret; 725 } 726 D1(printk(KERN_DEBUG "jffs2_garbage_collect_metadata(): Writing %d bites of symlink target\n", mdatalen)); 727 728 } 729 730 ret = jffs2_reserve_space_gc(c, sizeof(ri) + mdatalen, &alloclen, 731 JFFS2_SUMMARY_INODE_SIZE); 732 if (ret) { 733 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_metadata failed: %d\n", 734 sizeof(ri)+ mdatalen, ret); 735 goto out; 736 } 737 738 last_frag = frag_last(&f->fragtree); 739 if (last_frag) 740 /* Fetch the inode length from the fragtree rather then 741 * from i_size since i_size may have not been updated yet */ 742 ilen = last_frag->ofs + last_frag->size; 743 else 744 ilen = JFFS2_F_I_SIZE(f); 745 746 memset(&ri, 0, sizeof(ri)); 747 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 748 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 749 ri.totlen = cpu_to_je32(sizeof(ri) + mdatalen); 750 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 751 752 ri.ino = cpu_to_je32(f->inocache->ino); 753 ri.version = cpu_to_je32(++f->highest_version); 754 ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f)); 755 ri.uid = cpu_to_je16(JFFS2_F_I_UID(f)); 756 ri.gid = cpu_to_je16(JFFS2_F_I_GID(f)); 757 ri.isize = cpu_to_je32(ilen); 758 ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f)); 759 ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f)); 760 ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 761 ri.offset = cpu_to_je32(0); 762 ri.csize = cpu_to_je32(mdatalen); 763 ri.dsize = cpu_to_je32(mdatalen); 764 ri.compr = JFFS2_COMPR_NONE; 765 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 766 ri.data_crc = cpu_to_je32(crc32(0, mdata, mdatalen)); 767 768 new_fn = jffs2_write_dnode(c, f, &ri, mdata, mdatalen, ALLOC_GC); 769 770 if (IS_ERR(new_fn)) { 771 printk(KERN_WARNING "Error writing new dnode: %ld\n", PTR_ERR(new_fn)); 772 ret = PTR_ERR(new_fn); 773 goto out; 774 } 775 jffs2_mark_node_obsolete(c, fn->raw); 776 jffs2_free_full_dnode(fn); 777 f->metadata = new_fn; 778 out: 779 if (S_ISLNK(JFFS2_F_I_MODE(f))) 780 kfree(mdata); 781 return ret; 782 } 783 784 static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 785 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd) 786 { 787 struct jffs2_full_dirent *new_fd; 788 struct jffs2_raw_dirent rd; 789 uint32_t alloclen; 790 int ret; 791 792 rd.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 793 rd.nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT); 794 rd.nsize = strlen(fd->name); 795 rd.totlen = cpu_to_je32(sizeof(rd) + rd.nsize); 796 rd.hdr_crc = cpu_to_je32(crc32(0, &rd, sizeof(struct jffs2_unknown_node)-4)); 797 798 rd.pino = cpu_to_je32(f->inocache->ino); 799 rd.version = cpu_to_je32(++f->highest_version); 800 rd.ino = cpu_to_je32(fd->ino); 801 /* If the times on this inode were set by explicit utime() they can be different, 802 so refrain from splatting them. */ 803 if (JFFS2_F_I_MTIME(f) == JFFS2_F_I_CTIME(f)) 804 rd.mctime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 805 else 806 rd.mctime = cpu_to_je32(0); 807 rd.type = fd->type; 808 rd.node_crc = cpu_to_je32(crc32(0, &rd, sizeof(rd)-8)); 809 rd.name_crc = cpu_to_je32(crc32(0, fd->name, rd.nsize)); 810 811 ret = jffs2_reserve_space_gc(c, sizeof(rd)+rd.nsize, &alloclen, 812 JFFS2_SUMMARY_DIRENT_SIZE(rd.nsize)); 813 if (ret) { 814 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_dirent failed: %d\n", 815 sizeof(rd)+rd.nsize, ret); 816 return ret; 817 } 818 new_fd = jffs2_write_dirent(c, f, &rd, fd->name, rd.nsize, ALLOC_GC); 819 820 if (IS_ERR(new_fd)) { 821 printk(KERN_WARNING "jffs2_write_dirent in garbage_collect_dirent failed: %ld\n", PTR_ERR(new_fd)); 822 return PTR_ERR(new_fd); 823 } 824 jffs2_add_fd_to_list(c, new_fd, &f->dents); 825 return 0; 826 } 827 828 static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 829 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd) 830 { 831 struct jffs2_full_dirent **fdp = &f->dents; 832 int found = 0; 833 834 /* On a medium where we can't actually mark nodes obsolete 835 pernamently, such as NAND flash, we need to work out 836 whether this deletion dirent is still needed to actively 837 delete a 'real' dirent with the same name that's still 838 somewhere else on the flash. */ 839 if (!jffs2_can_mark_obsolete(c)) { 840 struct jffs2_raw_dirent *rd; 841 struct jffs2_raw_node_ref *raw; 842 int ret; 843 size_t retlen; 844 int name_len = strlen(fd->name); 845 uint32_t name_crc = crc32(0, fd->name, name_len); 846 uint32_t rawlen = ref_totlen(c, jeb, fd->raw); 847 848 rd = kmalloc(rawlen, GFP_KERNEL); 849 if (!rd) 850 return -ENOMEM; 851 852 /* Prevent the erase code from nicking the obsolete node refs while 853 we're looking at them. I really don't like this extra lock but 854 can't see any alternative. Suggestions on a postcard to... */ 855 mutex_lock(&c->erase_free_sem); 856 857 for (raw = f->inocache->nodes; raw != (void *)f->inocache; raw = raw->next_in_ino) { 858 859 cond_resched(); 860 861 /* We only care about obsolete ones */ 862 if (!(ref_obsolete(raw))) 863 continue; 864 865 /* Any dirent with the same name is going to have the same length... */ 866 if (ref_totlen(c, NULL, raw) != rawlen) 867 continue; 868 869 /* Doesn't matter if there's one in the same erase block. We're going to 870 delete it too at the same time. */ 871 if (SECTOR_ADDR(raw->flash_offset) == SECTOR_ADDR(fd->raw->flash_offset)) 872 continue; 873 874 D1(printk(KERN_DEBUG "Check potential deletion dirent at %08x\n", ref_offset(raw))); 875 876 /* This is an obsolete node belonging to the same directory, and it's of the right 877 length. We need to take a closer look...*/ 878 ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)rd); 879 if (ret) { 880 printk(KERN_WARNING "jffs2_g_c_deletion_dirent(): Read error (%d) reading obsolete node at %08x\n", ret, ref_offset(raw)); 881 /* If we can't read it, we don't need to continue to obsolete it. Continue */ 882 continue; 883 } 884 if (retlen != rawlen) { 885 printk(KERN_WARNING "jffs2_g_c_deletion_dirent(): Short read (%zd not %u) reading header from obsolete node at %08x\n", 886 retlen, rawlen, ref_offset(raw)); 887 continue; 888 } 889 890 if (je16_to_cpu(rd->nodetype) != JFFS2_NODETYPE_DIRENT) 891 continue; 892 893 /* If the name CRC doesn't match, skip */ 894 if (je32_to_cpu(rd->name_crc) != name_crc) 895 continue; 896 897 /* If the name length doesn't match, or it's another deletion dirent, skip */ 898 if (rd->nsize != name_len || !je32_to_cpu(rd->ino)) 899 continue; 900 901 /* OK, check the actual name now */ 902 if (memcmp(rd->name, fd->name, name_len)) 903 continue; 904 905 /* OK. The name really does match. There really is still an older node on 906 the flash which our deletion dirent obsoletes. So we have to write out 907 a new deletion dirent to replace it */ 908 mutex_unlock(&c->erase_free_sem); 909 910 D1(printk(KERN_DEBUG "Deletion dirent at %08x still obsoletes real dirent \"%s\" at %08x for ino #%u\n", 911 ref_offset(fd->raw), fd->name, ref_offset(raw), je32_to_cpu(rd->ino))); 912 kfree(rd); 913 914 return jffs2_garbage_collect_dirent(c, jeb, f, fd); 915 } 916 917 mutex_unlock(&c->erase_free_sem); 918 kfree(rd); 919 } 920 921 /* FIXME: If we're deleting a dirent which contains the current mtime and ctime, 922 we should update the metadata node with those times accordingly */ 923 924 /* No need for it any more. Just mark it obsolete and remove it from the list */ 925 while (*fdp) { 926 if ((*fdp) == fd) { 927 found = 1; 928 *fdp = fd->next; 929 break; 930 } 931 fdp = &(*fdp)->next; 932 } 933 if (!found) { 934 printk(KERN_WARNING "Deletion dirent \"%s\" not found in list for ino #%u\n", fd->name, f->inocache->ino); 935 } 936 jffs2_mark_node_obsolete(c, fd->raw); 937 jffs2_free_full_dirent(fd); 938 return 0; 939 } 940 941 static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 942 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 943 uint32_t start, uint32_t end) 944 { 945 struct jffs2_raw_inode ri; 946 struct jffs2_node_frag *frag; 947 struct jffs2_full_dnode *new_fn; 948 uint32_t alloclen, ilen; 949 int ret; 950 951 D1(printk(KERN_DEBUG "Writing replacement hole node for ino #%u from offset 0x%x to 0x%x\n", 952 f->inocache->ino, start, end)); 953 954 memset(&ri, 0, sizeof(ri)); 955 956 if(fn->frags > 1) { 957 size_t readlen; 958 uint32_t crc; 959 /* It's partially obsoleted by a later write. So we have to 960 write it out again with the _same_ version as before */ 961 ret = jffs2_flash_read(c, ref_offset(fn->raw), sizeof(ri), &readlen, (char *)&ri); 962 if (readlen != sizeof(ri) || ret) { 963 printk(KERN_WARNING "Node read failed in jffs2_garbage_collect_hole. Ret %d, retlen %zd. Data will be lost by writing new hole node\n", ret, readlen); 964 goto fill; 965 } 966 if (je16_to_cpu(ri.nodetype) != JFFS2_NODETYPE_INODE) { 967 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node at 0x%08x had node type 0x%04x instead of JFFS2_NODETYPE_INODE(0x%04x)\n", 968 ref_offset(fn->raw), 969 je16_to_cpu(ri.nodetype), JFFS2_NODETYPE_INODE); 970 return -EIO; 971 } 972 if (je32_to_cpu(ri.totlen) != sizeof(ri)) { 973 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node at 0x%08x had totlen 0x%x instead of expected 0x%zx\n", 974 ref_offset(fn->raw), 975 je32_to_cpu(ri.totlen), sizeof(ri)); 976 return -EIO; 977 } 978 crc = crc32(0, &ri, sizeof(ri)-8); 979 if (crc != je32_to_cpu(ri.node_crc)) { 980 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node at 0x%08x had CRC 0x%08x which doesn't match calculated CRC 0x%08x\n", 981 ref_offset(fn->raw), 982 je32_to_cpu(ri.node_crc), crc); 983 /* FIXME: We could possibly deal with this by writing new holes for each frag */ 984 printk(KERN_WARNING "Data in the range 0x%08x to 0x%08x of inode #%u will be lost\n", 985 start, end, f->inocache->ino); 986 goto fill; 987 } 988 if (ri.compr != JFFS2_COMPR_ZERO) { 989 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node 0x%08x wasn't a hole node!\n", ref_offset(fn->raw)); 990 printk(KERN_WARNING "Data in the range 0x%08x to 0x%08x of inode #%u will be lost\n", 991 start, end, f->inocache->ino); 992 goto fill; 993 } 994 } else { 995 fill: 996 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 997 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 998 ri.totlen = cpu_to_je32(sizeof(ri)); 999 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1000 1001 ri.ino = cpu_to_je32(f->inocache->ino); 1002 ri.version = cpu_to_je32(++f->highest_version); 1003 ri.offset = cpu_to_je32(start); 1004 ri.dsize = cpu_to_je32(end - start); 1005 ri.csize = cpu_to_je32(0); 1006 ri.compr = JFFS2_COMPR_ZERO; 1007 } 1008 1009 frag = frag_last(&f->fragtree); 1010 if (frag) 1011 /* Fetch the inode length from the fragtree rather then 1012 * from i_size since i_size may have not been updated yet */ 1013 ilen = frag->ofs + frag->size; 1014 else 1015 ilen = JFFS2_F_I_SIZE(f); 1016 1017 ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f)); 1018 ri.uid = cpu_to_je16(JFFS2_F_I_UID(f)); 1019 ri.gid = cpu_to_je16(JFFS2_F_I_GID(f)); 1020 ri.isize = cpu_to_je32(ilen); 1021 ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f)); 1022 ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f)); 1023 ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 1024 ri.data_crc = cpu_to_je32(0); 1025 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1026 1027 ret = jffs2_reserve_space_gc(c, sizeof(ri), &alloclen, 1028 JFFS2_SUMMARY_INODE_SIZE); 1029 if (ret) { 1030 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_hole failed: %d\n", 1031 sizeof(ri), ret); 1032 return ret; 1033 } 1034 new_fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_GC); 1035 1036 if (IS_ERR(new_fn)) { 1037 printk(KERN_WARNING "Error writing new hole node: %ld\n", PTR_ERR(new_fn)); 1038 return PTR_ERR(new_fn); 1039 } 1040 if (je32_to_cpu(ri.version) == f->highest_version) { 1041 jffs2_add_full_dnode_to_inode(c, f, new_fn); 1042 if (f->metadata) { 1043 jffs2_mark_node_obsolete(c, f->metadata->raw); 1044 jffs2_free_full_dnode(f->metadata); 1045 f->metadata = NULL; 1046 } 1047 return 0; 1048 } 1049 1050 /* 1051 * We should only get here in the case where the node we are 1052 * replacing had more than one frag, so we kept the same version 1053 * number as before. (Except in case of error -- see 'goto fill;' 1054 * above.) 1055 */ 1056 D1(if(unlikely(fn->frags <= 1)) { 1057 printk(KERN_WARNING "jffs2_garbage_collect_hole: Replacing fn with %d frag(s) but new ver %d != highest_version %d of ino #%d\n", 1058 fn->frags, je32_to_cpu(ri.version), f->highest_version, 1059 je32_to_cpu(ri.ino)); 1060 }); 1061 1062 /* This is a partially-overlapped hole node. Mark it REF_NORMAL not REF_PRISTINE */ 1063 mark_ref_normal(new_fn->raw); 1064 1065 for (frag = jffs2_lookup_node_frag(&f->fragtree, fn->ofs); 1066 frag; frag = frag_next(frag)) { 1067 if (frag->ofs > fn->size + fn->ofs) 1068 break; 1069 if (frag->node == fn) { 1070 frag->node = new_fn; 1071 new_fn->frags++; 1072 fn->frags--; 1073 } 1074 } 1075 if (fn->frags) { 1076 printk(KERN_WARNING "jffs2_garbage_collect_hole: Old node still has frags!\n"); 1077 BUG(); 1078 } 1079 if (!new_fn->frags) { 1080 printk(KERN_WARNING "jffs2_garbage_collect_hole: New node has no frags!\n"); 1081 BUG(); 1082 } 1083 1084 jffs2_mark_node_obsolete(c, fn->raw); 1085 jffs2_free_full_dnode(fn); 1086 1087 return 0; 1088 } 1089 1090 static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *orig_jeb, 1091 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 1092 uint32_t start, uint32_t end) 1093 { 1094 struct jffs2_full_dnode *new_fn; 1095 struct jffs2_raw_inode ri; 1096 uint32_t alloclen, offset, orig_end, orig_start; 1097 int ret = 0; 1098 unsigned char *comprbuf = NULL, *writebuf; 1099 unsigned long pg; 1100 unsigned char *pg_ptr; 1101 1102 memset(&ri, 0, sizeof(ri)); 1103 1104 D1(printk(KERN_DEBUG "Writing replacement dnode for ino #%u from offset 0x%x to 0x%x\n", 1105 f->inocache->ino, start, end)); 1106 1107 orig_end = end; 1108 orig_start = start; 1109 1110 if (c->nr_free_blocks + c->nr_erasing_blocks > c->resv_blocks_gcmerge) { 1111 /* Attempt to do some merging. But only expand to cover logically 1112 adjacent frags if the block containing them is already considered 1113 to be dirty. Otherwise we end up with GC just going round in 1114 circles dirtying the nodes it already wrote out, especially 1115 on NAND where we have small eraseblocks and hence a much higher 1116 chance of nodes having to be split to cross boundaries. */ 1117 1118 struct jffs2_node_frag *frag; 1119 uint32_t min, max; 1120 1121 min = start & ~(PAGE_CACHE_SIZE-1); 1122 max = min + PAGE_CACHE_SIZE; 1123 1124 frag = jffs2_lookup_node_frag(&f->fragtree, start); 1125 1126 /* BUG_ON(!frag) but that'll happen anyway... */ 1127 1128 BUG_ON(frag->ofs != start); 1129 1130 /* First grow down... */ 1131 while((frag = frag_prev(frag)) && frag->ofs >= min) { 1132 1133 /* If the previous frag doesn't even reach the beginning, there's 1134 excessive fragmentation. Just merge. */ 1135 if (frag->ofs > min) { 1136 D1(printk(KERN_DEBUG "Expanding down to cover partial frag (0x%x-0x%x)\n", 1137 frag->ofs, frag->ofs+frag->size)); 1138 start = frag->ofs; 1139 continue; 1140 } 1141 /* OK. This frag holds the first byte of the page. */ 1142 if (!frag->node || !frag->node->raw) { 1143 D1(printk(KERN_DEBUG "First frag in page is hole (0x%x-0x%x). Not expanding down.\n", 1144 frag->ofs, frag->ofs+frag->size)); 1145 break; 1146 } else { 1147 1148 /* OK, it's a frag which extends to the beginning of the page. Does it live 1149 in a block which is still considered clean? If so, don't obsolete it. 1150 If not, cover it anyway. */ 1151 1152 struct jffs2_raw_node_ref *raw = frag->node->raw; 1153 struct jffs2_eraseblock *jeb; 1154 1155 jeb = &c->blocks[raw->flash_offset / c->sector_size]; 1156 1157 if (jeb == c->gcblock) { 1158 D1(printk(KERN_DEBUG "Expanding down to cover frag (0x%x-0x%x) in gcblock at %08x\n", 1159 frag->ofs, frag->ofs+frag->size, ref_offset(raw))); 1160 start = frag->ofs; 1161 break; 1162 } 1163 if (!ISDIRTY(jeb->dirty_size + jeb->wasted_size)) { 1164 D1(printk(KERN_DEBUG "Not expanding down to cover frag (0x%x-0x%x) in clean block %08x\n", 1165 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1166 break; 1167 } 1168 1169 D1(printk(KERN_DEBUG "Expanding down to cover frag (0x%x-0x%x) in dirty block %08x\n", 1170 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1171 start = frag->ofs; 1172 break; 1173 } 1174 } 1175 1176 /* ... then up */ 1177 1178 /* Find last frag which is actually part of the node we're to GC. */ 1179 frag = jffs2_lookup_node_frag(&f->fragtree, end-1); 1180 1181 while((frag = frag_next(frag)) && frag->ofs+frag->size <= max) { 1182 1183 /* If the previous frag doesn't even reach the beginning, there's lots 1184 of fragmentation. Just merge. */ 1185 if (frag->ofs+frag->size < max) { 1186 D1(printk(KERN_DEBUG "Expanding up to cover partial frag (0x%x-0x%x)\n", 1187 frag->ofs, frag->ofs+frag->size)); 1188 end = frag->ofs + frag->size; 1189 continue; 1190 } 1191 1192 if (!frag->node || !frag->node->raw) { 1193 D1(printk(KERN_DEBUG "Last frag in page is hole (0x%x-0x%x). Not expanding up.\n", 1194 frag->ofs, frag->ofs+frag->size)); 1195 break; 1196 } else { 1197 1198 /* OK, it's a frag which extends to the beginning of the page. Does it live 1199 in a block which is still considered clean? If so, don't obsolete it. 1200 If not, cover it anyway. */ 1201 1202 struct jffs2_raw_node_ref *raw = frag->node->raw; 1203 struct jffs2_eraseblock *jeb; 1204 1205 jeb = &c->blocks[raw->flash_offset / c->sector_size]; 1206 1207 if (jeb == c->gcblock) { 1208 D1(printk(KERN_DEBUG "Expanding up to cover frag (0x%x-0x%x) in gcblock at %08x\n", 1209 frag->ofs, frag->ofs+frag->size, ref_offset(raw))); 1210 end = frag->ofs + frag->size; 1211 break; 1212 } 1213 if (!ISDIRTY(jeb->dirty_size + jeb->wasted_size)) { 1214 D1(printk(KERN_DEBUG "Not expanding up to cover frag (0x%x-0x%x) in clean block %08x\n", 1215 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1216 break; 1217 } 1218 1219 D1(printk(KERN_DEBUG "Expanding up to cover frag (0x%x-0x%x) in dirty block %08x\n", 1220 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1221 end = frag->ofs + frag->size; 1222 break; 1223 } 1224 } 1225 D1(printk(KERN_DEBUG "Expanded dnode to write from (0x%x-0x%x) to (0x%x-0x%x)\n", 1226 orig_start, orig_end, start, end)); 1227 1228 D1(BUG_ON(end > frag_last(&f->fragtree)->ofs + frag_last(&f->fragtree)->size)); 1229 BUG_ON(end < orig_end); 1230 BUG_ON(start > orig_start); 1231 } 1232 1233 /* First, use readpage() to read the appropriate page into the page cache */ 1234 /* Q: What happens if we actually try to GC the _same_ page for which commit_write() 1235 * triggered garbage collection in the first place? 1236 * A: I _think_ it's OK. read_cache_page shouldn't deadlock, we'll write out the 1237 * page OK. We'll actually write it out again in commit_write, which is a little 1238 * suboptimal, but at least we're correct. 1239 */ 1240 pg_ptr = jffs2_gc_fetch_page(c, f, start, &pg); 1241 1242 if (IS_ERR(pg_ptr)) { 1243 printk(KERN_WARNING "read_cache_page() returned error: %ld\n", PTR_ERR(pg_ptr)); 1244 return PTR_ERR(pg_ptr); 1245 } 1246 1247 offset = start; 1248 while(offset < orig_end) { 1249 uint32_t datalen; 1250 uint32_t cdatalen; 1251 uint16_t comprtype = JFFS2_COMPR_NONE; 1252 1253 ret = jffs2_reserve_space_gc(c, sizeof(ri) + JFFS2_MIN_DATA_LEN, 1254 &alloclen, JFFS2_SUMMARY_INODE_SIZE); 1255 1256 if (ret) { 1257 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_dnode failed: %d\n", 1258 sizeof(ri)+ JFFS2_MIN_DATA_LEN, ret); 1259 break; 1260 } 1261 cdatalen = min_t(uint32_t, alloclen - sizeof(ri), end - offset); 1262 datalen = end - offset; 1263 1264 writebuf = pg_ptr + (offset & (PAGE_CACHE_SIZE -1)); 1265 1266 comprtype = jffs2_compress(c, f, writebuf, &comprbuf, &datalen, &cdatalen); 1267 1268 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1269 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1270 ri.totlen = cpu_to_je32(sizeof(ri) + cdatalen); 1271 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1272 1273 ri.ino = cpu_to_je32(f->inocache->ino); 1274 ri.version = cpu_to_je32(++f->highest_version); 1275 ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f)); 1276 ri.uid = cpu_to_je16(JFFS2_F_I_UID(f)); 1277 ri.gid = cpu_to_je16(JFFS2_F_I_GID(f)); 1278 ri.isize = cpu_to_je32(JFFS2_F_I_SIZE(f)); 1279 ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f)); 1280 ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f)); 1281 ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 1282 ri.offset = cpu_to_je32(offset); 1283 ri.csize = cpu_to_je32(cdatalen); 1284 ri.dsize = cpu_to_je32(datalen); 1285 ri.compr = comprtype & 0xff; 1286 ri.usercompr = (comprtype >> 8) & 0xff; 1287 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1288 ri.data_crc = cpu_to_je32(crc32(0, comprbuf, cdatalen)); 1289 1290 new_fn = jffs2_write_dnode(c, f, &ri, comprbuf, cdatalen, ALLOC_GC); 1291 1292 jffs2_free_comprbuf(comprbuf, writebuf); 1293 1294 if (IS_ERR(new_fn)) { 1295 printk(KERN_WARNING "Error writing new dnode: %ld\n", PTR_ERR(new_fn)); 1296 ret = PTR_ERR(new_fn); 1297 break; 1298 } 1299 ret = jffs2_add_full_dnode_to_inode(c, f, new_fn); 1300 offset += datalen; 1301 if (f->metadata) { 1302 jffs2_mark_node_obsolete(c, f->metadata->raw); 1303 jffs2_free_full_dnode(f->metadata); 1304 f->metadata = NULL; 1305 } 1306 } 1307 1308 jffs2_gc_release_page(c, pg_ptr, &pg); 1309 return ret; 1310 } 1311