1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright (C) 2001-2003 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 * $Id: gc.c,v 1.154 2005/09/07 08:34:54 havasi Exp $ 11 * 12 */ 13 14 #include <linux/kernel.h> 15 #include <linux/mtd/mtd.h> 16 #include <linux/slab.h> 17 #include <linux/pagemap.h> 18 #include <linux/crc32.h> 19 #include <linux/compiler.h> 20 #include <linux/stat.h> 21 #include "nodelist.h" 22 #include "compr.h" 23 24 static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c, 25 struct jffs2_inode_cache *ic, 26 struct jffs2_raw_node_ref *raw); 27 static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 28 struct jffs2_inode_info *f, struct jffs2_full_dnode *fd); 29 static int jffs2_garbage_collect_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_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 32 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd); 33 static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 34 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 35 uint32_t start, uint32_t end); 36 static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 37 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 38 uint32_t start, uint32_t end); 39 static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 40 struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f); 41 42 /* Called with erase_completion_lock held */ 43 static struct jffs2_eraseblock *jffs2_find_gc_block(struct jffs2_sb_info *c) 44 { 45 struct jffs2_eraseblock *ret; 46 struct list_head *nextlist = NULL; 47 int n = jiffies % 128; 48 49 /* Pick an eraseblock to garbage collect next. This is where we'll 50 put the clever wear-levelling algorithms. Eventually. */ 51 /* We possibly want to favour the dirtier blocks more when the 52 number of free blocks is low. */ 53 again: 54 if (!list_empty(&c->bad_used_list) && c->nr_free_blocks > c->resv_blocks_gcbad) { 55 D1(printk(KERN_DEBUG "Picking block from bad_used_list to GC next\n")); 56 nextlist = &c->bad_used_list; 57 } else if (n < 50 && !list_empty(&c->erasable_list)) { 58 /* Note that most of them will have gone directly to be erased. 59 So don't favour the erasable_list _too_ much. */ 60 D1(printk(KERN_DEBUG "Picking block from erasable_list to GC next\n")); 61 nextlist = &c->erasable_list; 62 } else if (n < 110 && !list_empty(&c->very_dirty_list)) { 63 /* Most of the time, pick one off the very_dirty list */ 64 D1(printk(KERN_DEBUG "Picking block from very_dirty_list to GC next\n")); 65 nextlist = &c->very_dirty_list; 66 } else if (n < 126 && !list_empty(&c->dirty_list)) { 67 D1(printk(KERN_DEBUG "Picking block from dirty_list to GC next\n")); 68 nextlist = &c->dirty_list; 69 } else if (!list_empty(&c->clean_list)) { 70 D1(printk(KERN_DEBUG "Picking block from clean_list to GC next\n")); 71 nextlist = &c->clean_list; 72 } else if (!list_empty(&c->dirty_list)) { 73 D1(printk(KERN_DEBUG "Picking block from dirty_list to GC next (clean_list was empty)\n")); 74 75 nextlist = &c->dirty_list; 76 } else if (!list_empty(&c->very_dirty_list)) { 77 D1(printk(KERN_DEBUG "Picking block from very_dirty_list to GC next (clean_list and dirty_list were empty)\n")); 78 nextlist = &c->very_dirty_list; 79 } else if (!list_empty(&c->erasable_list)) { 80 D1(printk(KERN_DEBUG "Picking block from erasable_list to GC next (clean_list and {very_,}dirty_list were empty)\n")); 81 82 nextlist = &c->erasable_list; 83 } else if (!list_empty(&c->erasable_pending_wbuf_list)) { 84 /* There are blocks are wating for the wbuf sync */ 85 D1(printk(KERN_DEBUG "Synching wbuf in order to reuse erasable_pending_wbuf_list blocks\n")); 86 spin_unlock(&c->erase_completion_lock); 87 jffs2_flush_wbuf_pad(c); 88 spin_lock(&c->erase_completion_lock); 89 goto again; 90 } else { 91 /* Eep. All were empty */ 92 D1(printk(KERN_NOTICE "jffs2: No clean, dirty _or_ erasable blocks to GC from! Where are they all?\n")); 93 return NULL; 94 } 95 96 ret = list_entry(nextlist->next, struct jffs2_eraseblock, list); 97 list_del(&ret->list); 98 c->gcblock = ret; 99 ret->gc_node = ret->first_node; 100 if (!ret->gc_node) { 101 printk(KERN_WARNING "Eep. ret->gc_node for block at 0x%08x is NULL\n", ret->offset); 102 BUG(); 103 } 104 105 /* Have we accidentally picked a clean block with wasted space ? */ 106 if (ret->wasted_size) { 107 D1(printk(KERN_DEBUG "Converting wasted_size %08x to dirty_size\n", ret->wasted_size)); 108 ret->dirty_size += ret->wasted_size; 109 c->wasted_size -= ret->wasted_size; 110 c->dirty_size += ret->wasted_size; 111 ret->wasted_size = 0; 112 } 113 114 return ret; 115 } 116 117 /* jffs2_garbage_collect_pass 118 * Make a single attempt to progress GC. Move one node, and possibly 119 * start erasing one eraseblock. 120 */ 121 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c) 122 { 123 struct jffs2_inode_info *f; 124 struct jffs2_inode_cache *ic; 125 struct jffs2_eraseblock *jeb; 126 struct jffs2_raw_node_ref *raw; 127 int ret = 0, inum, nlink; 128 129 if (down_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) { 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 BUG(); 147 } 148 149 spin_unlock(&c->erase_completion_lock); 150 151 spin_lock(&c->inocache_lock); 152 153 ic = jffs2_get_ino_cache(c, c->checked_ino++); 154 155 if (!ic) { 156 spin_unlock(&c->inocache_lock); 157 continue; 158 } 159 160 if (!ic->nlink) { 161 D1(printk(KERN_DEBUG "Skipping check of ino #%d with nlink zero\n", 162 ic->ino)); 163 spin_unlock(&c->inocache_lock); 164 continue; 165 } 166 switch(ic->state) { 167 case INO_STATE_CHECKEDABSENT: 168 case INO_STATE_PRESENT: 169 D1(printk(KERN_DEBUG "Skipping ino #%u already checked\n", ic->ino)); 170 spin_unlock(&c->inocache_lock); 171 continue; 172 173 case INO_STATE_GC: 174 case INO_STATE_CHECKING: 175 printk(KERN_WARNING "Inode #%u is in state %d during CRC check phase!\n", ic->ino, ic->state); 176 spin_unlock(&c->inocache_lock); 177 BUG(); 178 179 case INO_STATE_READING: 180 /* We need to wait for it to finish, lest we move on 181 and trigger the BUG() above while we haven't yet 182 finished checking all its nodes */ 183 D1(printk(KERN_DEBUG "Waiting for ino #%u to finish reading\n", ic->ino)); 184 up(&c->alloc_sem); 185 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); 186 return 0; 187 188 default: 189 BUG(); 190 191 case INO_STATE_UNCHECKED: 192 ; 193 } 194 ic->state = INO_STATE_CHECKING; 195 spin_unlock(&c->inocache_lock); 196 197 D1(printk(KERN_DEBUG "jffs2_garbage_collect_pass() triggering inode scan of ino#%u\n", ic->ino)); 198 199 ret = jffs2_do_crccheck_inode(c, ic); 200 if (ret) 201 printk(KERN_WARNING "Returned error for crccheck of ino #%u. Expect badness...\n", ic->ino); 202 203 jffs2_set_inocache_state(c, ic, INO_STATE_CHECKEDABSENT); 204 up(&c->alloc_sem); 205 return ret; 206 } 207 208 /* First, work out which block we're garbage-collecting */ 209 jeb = c->gcblock; 210 211 if (!jeb) 212 jeb = jffs2_find_gc_block(c); 213 214 if (!jeb) { 215 D1 (printk(KERN_NOTICE "jffs2: Couldn't find erase block to garbage collect!\n")); 216 spin_unlock(&c->erase_completion_lock); 217 up(&c->alloc_sem); 218 return -EIO; 219 } 220 221 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)); 222 D1(if (c->nextblock) 223 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)); 224 225 if (!jeb->used_size) { 226 up(&c->alloc_sem); 227 goto eraseit; 228 } 229 230 raw = jeb->gc_node; 231 232 while(ref_obsolete(raw)) { 233 D1(printk(KERN_DEBUG "Node at 0x%08x is obsolete... skipping\n", ref_offset(raw))); 234 raw = raw->next_phys; 235 if (unlikely(!raw)) { 236 printk(KERN_WARNING "eep. End of raw list while still supposedly nodes to GC\n"); 237 printk(KERN_WARNING "erase block at 0x%08x. free_size 0x%08x, dirty_size 0x%08x, used_size 0x%08x\n", 238 jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size); 239 jeb->gc_node = raw; 240 spin_unlock(&c->erase_completion_lock); 241 up(&c->alloc_sem); 242 BUG(); 243 } 244 } 245 jeb->gc_node = raw; 246 247 D1(printk(KERN_DEBUG "Going to garbage collect node at 0x%08x\n", ref_offset(raw))); 248 249 if (!raw->next_in_ino) { 250 /* Inode-less node. Clean marker, snapshot or something like that */ 251 /* FIXME: If it's something that needs to be copied, including something 252 we don't grok that has JFFS2_NODETYPE_RWCOMPAT_COPY, we should do so */ 253 spin_unlock(&c->erase_completion_lock); 254 jffs2_mark_node_obsolete(c, raw); 255 up(&c->alloc_sem); 256 goto eraseit_lock; 257 } 258 259 ic = jffs2_raw_ref_to_ic(raw); 260 261 /* We need to hold the inocache. Either the erase_completion_lock or 262 the inocache_lock are sufficient; we trade down since the inocache_lock 263 causes less contention. */ 264 spin_lock(&c->inocache_lock); 265 266 spin_unlock(&c->erase_completion_lock); 267 268 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)); 269 270 /* Three possibilities: 271 1. Inode is already in-core. We must iget it and do proper 272 updating to its fragtree, etc. 273 2. Inode is not in-core, node is REF_PRISTINE. We lock the 274 inocache to prevent a read_inode(), copy the node intact. 275 3. Inode is not in-core, node is not pristine. We must iget() 276 and take the slow path. 277 */ 278 279 switch(ic->state) { 280 case INO_STATE_CHECKEDABSENT: 281 /* It's been checked, but it's not currently in-core. 282 We can just copy any pristine nodes, but have 283 to prevent anyone else from doing read_inode() while 284 we're at it, so we set the state accordingly */ 285 if (ref_flags(raw) == REF_PRISTINE) 286 ic->state = INO_STATE_GC; 287 else { 288 D1(printk(KERN_DEBUG "Ino #%u is absent but node not REF_PRISTINE. Reading.\n", 289 ic->ino)); 290 } 291 break; 292 293 case INO_STATE_PRESENT: 294 /* It's in-core. GC must iget() it. */ 295 break; 296 297 case INO_STATE_UNCHECKED: 298 case INO_STATE_CHECKING: 299 case INO_STATE_GC: 300 /* Should never happen. We should have finished checking 301 by the time we actually start doing any GC, and since 302 we're holding the alloc_sem, no other garbage collection 303 can happen. 304 */ 305 printk(KERN_CRIT "Inode #%u already in state %d in jffs2_garbage_collect_pass()!\n", 306 ic->ino, ic->state); 307 up(&c->alloc_sem); 308 spin_unlock(&c->inocache_lock); 309 BUG(); 310 311 case INO_STATE_READING: 312 /* Someone's currently trying to read it. We must wait for 313 them to finish and then go through the full iget() route 314 to do the GC. However, sometimes read_inode() needs to get 315 the alloc_sem() (for marking nodes invalid) so we must 316 drop the alloc_sem before sleeping. */ 317 318 up(&c->alloc_sem); 319 D1(printk(KERN_DEBUG "jffs2_garbage_collect_pass() waiting for ino #%u in state %d\n", 320 ic->ino, ic->state)); 321 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); 322 /* And because we dropped the alloc_sem we must start again from the 323 beginning. Ponder chance of livelock here -- we're returning success 324 without actually making any progress. 325 326 Q: What are the chances that the inode is back in INO_STATE_READING 327 again by the time we next enter this function? And that this happens 328 enough times to cause a real delay? 329 330 A: Small enough that I don't care :) 331 */ 332 return 0; 333 } 334 335 /* OK. Now if the inode is in state INO_STATE_GC, we are going to copy the 336 node intact, and we don't have to muck about with the fragtree etc. 337 because we know it's not in-core. If it _was_ in-core, we go through 338 all the iget() crap anyway */ 339 340 if (ic->state == INO_STATE_GC) { 341 spin_unlock(&c->inocache_lock); 342 343 ret = jffs2_garbage_collect_pristine(c, ic, raw); 344 345 spin_lock(&c->inocache_lock); 346 ic->state = INO_STATE_CHECKEDABSENT; 347 wake_up(&c->inocache_wq); 348 349 if (ret != -EBADFD) { 350 spin_unlock(&c->inocache_lock); 351 goto release_sem; 352 } 353 354 /* Fall through if it wanted us to, with inocache_lock held */ 355 } 356 357 /* Prevent the fairly unlikely race where the gcblock is 358 entirely obsoleted by the final close of a file which had 359 the only valid nodes in the block, followed by erasure, 360 followed by freeing of the ic because the erased block(s) 361 held _all_ the nodes of that inode.... never been seen but 362 it's vaguely possible. */ 363 364 inum = ic->ino; 365 nlink = ic->nlink; 366 spin_unlock(&c->inocache_lock); 367 368 f = jffs2_gc_fetch_inode(c, inum, nlink); 369 if (IS_ERR(f)) { 370 ret = PTR_ERR(f); 371 goto release_sem; 372 } 373 if (!f) { 374 ret = 0; 375 goto release_sem; 376 } 377 378 ret = jffs2_garbage_collect_live(c, jeb, raw, f); 379 380 jffs2_gc_release_inode(c, f); 381 382 release_sem: 383 up(&c->alloc_sem); 384 385 eraseit_lock: 386 /* If we've finished this block, start it erasing */ 387 spin_lock(&c->erase_completion_lock); 388 389 eraseit: 390 if (c->gcblock && !c->gcblock->used_size) { 391 D1(printk(KERN_DEBUG "Block at 0x%08x completely obsoleted by GC. Moving to erase_pending_list\n", c->gcblock->offset)); 392 /* We're GC'ing an empty block? */ 393 list_add_tail(&c->gcblock->list, &c->erase_pending_list); 394 c->gcblock = NULL; 395 c->nr_erasing_blocks++; 396 jffs2_erase_pending_trigger(c); 397 } 398 spin_unlock(&c->erase_completion_lock); 399 400 return ret; 401 } 402 403 static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 404 struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f) 405 { 406 struct jffs2_node_frag *frag; 407 struct jffs2_full_dnode *fn = NULL; 408 struct jffs2_full_dirent *fd; 409 uint32_t start = 0, end = 0, nrfrags = 0; 410 int ret = 0; 411 412 down(&f->sem); 413 414 /* Now we have the lock for this inode. Check that it's still the one at the head 415 of the list. */ 416 417 spin_lock(&c->erase_completion_lock); 418 419 if (c->gcblock != jeb) { 420 spin_unlock(&c->erase_completion_lock); 421 D1(printk(KERN_DEBUG "GC block is no longer gcblock. Restart\n")); 422 goto upnout; 423 } 424 if (ref_obsolete(raw)) { 425 spin_unlock(&c->erase_completion_lock); 426 D1(printk(KERN_DEBUG "node to be GC'd was obsoleted in the meantime.\n")); 427 /* They'll call again */ 428 goto upnout; 429 } 430 spin_unlock(&c->erase_completion_lock); 431 432 /* OK. Looks safe. And nobody can get us now because we have the semaphore. Move the block */ 433 if (f->metadata && f->metadata->raw == raw) { 434 fn = f->metadata; 435 ret = jffs2_garbage_collect_metadata(c, jeb, f, fn); 436 goto upnout; 437 } 438 439 /* FIXME. Read node and do lookup? */ 440 for (frag = frag_first(&f->fragtree); frag; frag = frag_next(frag)) { 441 if (frag->node && frag->node->raw == raw) { 442 fn = frag->node; 443 end = frag->ofs + frag->size; 444 if (!nrfrags++) 445 start = frag->ofs; 446 if (nrfrags == frag->node->frags) 447 break; /* We've found them all */ 448 } 449 } 450 if (fn) { 451 if (ref_flags(raw) == REF_PRISTINE) { 452 ret = jffs2_garbage_collect_pristine(c, f->inocache, raw); 453 if (!ret) { 454 /* Urgh. Return it sensibly. */ 455 frag->node->raw = f->inocache->nodes; 456 } 457 if (ret != -EBADFD) 458 goto upnout; 459 } 460 /* We found a datanode. Do the GC */ 461 if((start >> PAGE_CACHE_SHIFT) < ((end-1) >> PAGE_CACHE_SHIFT)) { 462 /* It crosses a page boundary. Therefore, it must be a hole. */ 463 ret = jffs2_garbage_collect_hole(c, jeb, f, fn, start, end); 464 } else { 465 /* It could still be a hole. But we GC the page this way anyway */ 466 ret = jffs2_garbage_collect_dnode(c, jeb, f, fn, start, end); 467 } 468 goto upnout; 469 } 470 471 /* Wasn't a dnode. Try dirent */ 472 for (fd = f->dents; fd; fd=fd->next) { 473 if (fd->raw == raw) 474 break; 475 } 476 477 if (fd && fd->ino) { 478 ret = jffs2_garbage_collect_dirent(c, jeb, f, fd); 479 } else if (fd) { 480 ret = jffs2_garbage_collect_deletion_dirent(c, jeb, f, fd); 481 } else { 482 printk(KERN_WARNING "Raw node at 0x%08x wasn't in node lists for ino #%u\n", 483 ref_offset(raw), f->inocache->ino); 484 if (ref_obsolete(raw)) { 485 printk(KERN_WARNING "But it's obsolete so we don't mind too much\n"); 486 } else { 487 jffs2_dbg_dump_node(c, ref_offset(raw)); 488 BUG(); 489 } 490 } 491 upnout: 492 up(&f->sem); 493 494 return ret; 495 } 496 497 static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c, 498 struct jffs2_inode_cache *ic, 499 struct jffs2_raw_node_ref *raw) 500 { 501 union jffs2_node_union *node; 502 struct jffs2_raw_node_ref *nraw; 503 size_t retlen; 504 int ret; 505 uint32_t phys_ofs, alloclen; 506 uint32_t crc, rawlen; 507 int retried = 0; 508 509 D1(printk(KERN_DEBUG "Going to GC REF_PRISTINE node at 0x%08x\n", ref_offset(raw))); 510 511 rawlen = ref_totlen(c, c->gcblock, raw); 512 513 /* Ask for a small amount of space (or the totlen if smaller) because we 514 don't want to force wastage of the end of a block if splitting would 515 work. */ 516 ret = jffs2_reserve_space_gc(c, min_t(uint32_t, sizeof(struct jffs2_raw_inode) + 517 JFFS2_MIN_DATA_LEN, rawlen), &phys_ofs, &alloclen, rawlen); 518 /* this is not the exact summary size of it, 519 it is only an upper estimation */ 520 521 if (ret) 522 return ret; 523 524 if (alloclen < rawlen) { 525 /* Doesn't fit untouched. We'll go the old route and split it */ 526 return -EBADFD; 527 } 528 529 node = kmalloc(rawlen, GFP_KERNEL); 530 if (!node) 531 return -ENOMEM; 532 533 ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)node); 534 if (!ret && retlen != rawlen) 535 ret = -EIO; 536 if (ret) 537 goto out_node; 538 539 crc = crc32(0, node, sizeof(struct jffs2_unknown_node)-4); 540 if (je32_to_cpu(node->u.hdr_crc) != crc) { 541 printk(KERN_WARNING "Header CRC failed on REF_PRISTINE node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 542 ref_offset(raw), je32_to_cpu(node->u.hdr_crc), crc); 543 goto bail; 544 } 545 546 switch(je16_to_cpu(node->u.nodetype)) { 547 case JFFS2_NODETYPE_INODE: 548 crc = crc32(0, node, sizeof(node->i)-8); 549 if (je32_to_cpu(node->i.node_crc) != crc) { 550 printk(KERN_WARNING "Node CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 551 ref_offset(raw), je32_to_cpu(node->i.node_crc), crc); 552 goto bail; 553 } 554 555 if (je32_to_cpu(node->i.dsize)) { 556 crc = crc32(0, node->i.data, je32_to_cpu(node->i.csize)); 557 if (je32_to_cpu(node->i.data_crc) != crc) { 558 printk(KERN_WARNING "Data CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 559 ref_offset(raw), je32_to_cpu(node->i.data_crc), crc); 560 goto bail; 561 } 562 } 563 break; 564 565 case JFFS2_NODETYPE_DIRENT: 566 crc = crc32(0, node, sizeof(node->d)-8); 567 if (je32_to_cpu(node->d.node_crc) != crc) { 568 printk(KERN_WARNING "Node CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 569 ref_offset(raw), je32_to_cpu(node->d.node_crc), crc); 570 goto bail; 571 } 572 573 if (node->d.nsize) { 574 crc = crc32(0, node->d.name, node->d.nsize); 575 if (je32_to_cpu(node->d.name_crc) != crc) { 576 printk(KERN_WARNING "Name CRC failed on REF_PRISTINE dirent ode at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 577 ref_offset(raw), je32_to_cpu(node->d.name_crc), crc); 578 goto bail; 579 } 580 } 581 break; 582 default: 583 printk(KERN_WARNING "Unknown node type for REF_PRISTINE node at 0x%08x: 0x%04x\n", 584 ref_offset(raw), je16_to_cpu(node->u.nodetype)); 585 goto bail; 586 } 587 588 nraw = jffs2_alloc_raw_node_ref(); 589 if (!nraw) { 590 ret = -ENOMEM; 591 goto out_node; 592 } 593 594 /* OK, all the CRCs are good; this node can just be copied as-is. */ 595 retry: 596 nraw->flash_offset = phys_ofs; 597 nraw->__totlen = rawlen; 598 nraw->next_phys = NULL; 599 600 ret = jffs2_flash_write(c, phys_ofs, rawlen, &retlen, (char *)node); 601 602 if (ret || (retlen != rawlen)) { 603 printk(KERN_NOTICE "Write of %d bytes at 0x%08x failed. returned %d, retlen %zd\n", 604 rawlen, phys_ofs, ret, retlen); 605 if (retlen) { 606 /* Doesn't belong to any inode */ 607 nraw->next_in_ino = NULL; 608 609 nraw->flash_offset |= REF_OBSOLETE; 610 jffs2_add_physical_node_ref(c, nraw); 611 jffs2_mark_node_obsolete(c, nraw); 612 } else { 613 printk(KERN_NOTICE "Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n", nraw->flash_offset); 614 jffs2_free_raw_node_ref(nraw); 615 } 616 if (!retried && (nraw = jffs2_alloc_raw_node_ref())) { 617 /* Try to reallocate space and retry */ 618 uint32_t dummy; 619 struct jffs2_eraseblock *jeb = &c->blocks[phys_ofs / c->sector_size]; 620 621 retried = 1; 622 623 D1(printk(KERN_DEBUG "Retrying failed write of REF_PRISTINE node.\n")); 624 625 jffs2_dbg_acct_sanity_check(c,jeb); 626 jffs2_dbg_acct_paranoia_check(c, jeb); 627 628 ret = jffs2_reserve_space_gc(c, rawlen, &phys_ofs, &dummy, rawlen); 629 /* this is not the exact summary size of it, 630 it is only an upper estimation */ 631 632 if (!ret) { 633 D1(printk(KERN_DEBUG "Allocated space at 0x%08x to retry failed write.\n", phys_ofs)); 634 635 jffs2_dbg_acct_sanity_check(c,jeb); 636 jffs2_dbg_acct_paranoia_check(c, jeb); 637 638 goto retry; 639 } 640 D1(printk(KERN_DEBUG "Failed to allocate space to retry failed write: %d!\n", ret)); 641 jffs2_free_raw_node_ref(nraw); 642 } 643 644 jffs2_free_raw_node_ref(nraw); 645 if (!ret) 646 ret = -EIO; 647 goto out_node; 648 } 649 nraw->flash_offset |= REF_PRISTINE; 650 jffs2_add_physical_node_ref(c, nraw); 651 652 /* Link into per-inode list. This is safe because of the ic 653 state being INO_STATE_GC. Note that if we're doing this 654 for an inode which is in-core, the 'nraw' pointer is then 655 going to be fetched from ic->nodes by our caller. */ 656 spin_lock(&c->erase_completion_lock); 657 nraw->next_in_ino = ic->nodes; 658 ic->nodes = nraw; 659 spin_unlock(&c->erase_completion_lock); 660 661 jffs2_mark_node_obsolete(c, raw); 662 D1(printk(KERN_DEBUG "WHEEE! GC REF_PRISTINE node at 0x%08x succeeded\n", ref_offset(raw))); 663 664 out_node: 665 kfree(node); 666 return ret; 667 bail: 668 ret = -EBADFD; 669 goto out_node; 670 } 671 672 static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 673 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn) 674 { 675 struct jffs2_full_dnode *new_fn; 676 struct jffs2_raw_inode ri; 677 struct jffs2_node_frag *last_frag; 678 jint16_t dev; 679 char *mdata = NULL, mdatalen = 0; 680 uint32_t alloclen, phys_ofs, ilen; 681 int ret; 682 683 if (S_ISBLK(JFFS2_F_I_MODE(f)) || 684 S_ISCHR(JFFS2_F_I_MODE(f)) ) { 685 /* For these, we don't actually need to read the old node */ 686 /* FIXME: for minor or major > 255. */ 687 dev = cpu_to_je16(((JFFS2_F_I_RDEV_MAJ(f) << 8) | 688 JFFS2_F_I_RDEV_MIN(f))); 689 mdata = (char *)&dev; 690 mdatalen = sizeof(dev); 691 D1(printk(KERN_DEBUG "jffs2_garbage_collect_metadata(): Writing %d bytes of kdev_t\n", mdatalen)); 692 } else if (S_ISLNK(JFFS2_F_I_MODE(f))) { 693 mdatalen = fn->size; 694 mdata = kmalloc(fn->size, GFP_KERNEL); 695 if (!mdata) { 696 printk(KERN_WARNING "kmalloc of mdata failed in jffs2_garbage_collect_metadata()\n"); 697 return -ENOMEM; 698 } 699 ret = jffs2_read_dnode(c, f, fn, mdata, 0, mdatalen); 700 if (ret) { 701 printk(KERN_WARNING "read of old metadata failed in jffs2_garbage_collect_metadata(): %d\n", ret); 702 kfree(mdata); 703 return ret; 704 } 705 D1(printk(KERN_DEBUG "jffs2_garbage_collect_metadata(): Writing %d bites of symlink target\n", mdatalen)); 706 707 } 708 709 ret = jffs2_reserve_space_gc(c, sizeof(ri) + mdatalen, &phys_ofs, &alloclen, 710 JFFS2_SUMMARY_INODE_SIZE); 711 if (ret) { 712 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_metadata failed: %d\n", 713 sizeof(ri)+ mdatalen, ret); 714 goto out; 715 } 716 717 last_frag = frag_last(&f->fragtree); 718 if (last_frag) 719 /* Fetch the inode length from the fragtree rather then 720 * from i_size since i_size may have not been updated yet */ 721 ilen = last_frag->ofs + last_frag->size; 722 else 723 ilen = JFFS2_F_I_SIZE(f); 724 725 memset(&ri, 0, sizeof(ri)); 726 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 727 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 728 ri.totlen = cpu_to_je32(sizeof(ri) + mdatalen); 729 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 730 731 ri.ino = cpu_to_je32(f->inocache->ino); 732 ri.version = cpu_to_je32(++f->highest_version); 733 ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f)); 734 ri.uid = cpu_to_je16(JFFS2_F_I_UID(f)); 735 ri.gid = cpu_to_je16(JFFS2_F_I_GID(f)); 736 ri.isize = cpu_to_je32(ilen); 737 ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f)); 738 ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f)); 739 ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 740 ri.offset = cpu_to_je32(0); 741 ri.csize = cpu_to_je32(mdatalen); 742 ri.dsize = cpu_to_je32(mdatalen); 743 ri.compr = JFFS2_COMPR_NONE; 744 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 745 ri.data_crc = cpu_to_je32(crc32(0, mdata, mdatalen)); 746 747 new_fn = jffs2_write_dnode(c, f, &ri, mdata, mdatalen, phys_ofs, ALLOC_GC); 748 749 if (IS_ERR(new_fn)) { 750 printk(KERN_WARNING "Error writing new dnode: %ld\n", PTR_ERR(new_fn)); 751 ret = PTR_ERR(new_fn); 752 goto out; 753 } 754 jffs2_mark_node_obsolete(c, fn->raw); 755 jffs2_free_full_dnode(fn); 756 f->metadata = new_fn; 757 out: 758 if (S_ISLNK(JFFS2_F_I_MODE(f))) 759 kfree(mdata); 760 return ret; 761 } 762 763 static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 764 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd) 765 { 766 struct jffs2_full_dirent *new_fd; 767 struct jffs2_raw_dirent rd; 768 uint32_t alloclen, phys_ofs; 769 int ret; 770 771 rd.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 772 rd.nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT); 773 rd.nsize = strlen(fd->name); 774 rd.totlen = cpu_to_je32(sizeof(rd) + rd.nsize); 775 rd.hdr_crc = cpu_to_je32(crc32(0, &rd, sizeof(struct jffs2_unknown_node)-4)); 776 777 rd.pino = cpu_to_je32(f->inocache->ino); 778 rd.version = cpu_to_je32(++f->highest_version); 779 rd.ino = cpu_to_je32(fd->ino); 780 /* If the times on this inode were set by explicit utime() they can be different, 781 so refrain from splatting them. */ 782 if (JFFS2_F_I_MTIME(f) == JFFS2_F_I_CTIME(f)) 783 rd.mctime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 784 else 785 rd.mctime = cpu_to_je32(0); 786 rd.type = fd->type; 787 rd.node_crc = cpu_to_je32(crc32(0, &rd, sizeof(rd)-8)); 788 rd.name_crc = cpu_to_je32(crc32(0, fd->name, rd.nsize)); 789 790 ret = jffs2_reserve_space_gc(c, sizeof(rd)+rd.nsize, &phys_ofs, &alloclen, 791 JFFS2_SUMMARY_DIRENT_SIZE(rd.nsize)); 792 if (ret) { 793 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_dirent failed: %d\n", 794 sizeof(rd)+rd.nsize, ret); 795 return ret; 796 } 797 new_fd = jffs2_write_dirent(c, f, &rd, fd->name, rd.nsize, phys_ofs, ALLOC_GC); 798 799 if (IS_ERR(new_fd)) { 800 printk(KERN_WARNING "jffs2_write_dirent in garbage_collect_dirent failed: %ld\n", PTR_ERR(new_fd)); 801 return PTR_ERR(new_fd); 802 } 803 jffs2_add_fd_to_list(c, new_fd, &f->dents); 804 return 0; 805 } 806 807 static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 808 struct jffs2_inode_info *f, struct jffs2_full_dirent *fd) 809 { 810 struct jffs2_full_dirent **fdp = &f->dents; 811 int found = 0; 812 813 /* On a medium where we can't actually mark nodes obsolete 814 pernamently, such as NAND flash, we need to work out 815 whether this deletion dirent is still needed to actively 816 delete a 'real' dirent with the same name that's still 817 somewhere else on the flash. */ 818 if (!jffs2_can_mark_obsolete(c)) { 819 struct jffs2_raw_dirent *rd; 820 struct jffs2_raw_node_ref *raw; 821 int ret; 822 size_t retlen; 823 int name_len = strlen(fd->name); 824 uint32_t name_crc = crc32(0, fd->name, name_len); 825 uint32_t rawlen = ref_totlen(c, jeb, fd->raw); 826 827 rd = kmalloc(rawlen, GFP_KERNEL); 828 if (!rd) 829 return -ENOMEM; 830 831 /* Prevent the erase code from nicking the obsolete node refs while 832 we're looking at them. I really don't like this extra lock but 833 can't see any alternative. Suggestions on a postcard to... */ 834 down(&c->erase_free_sem); 835 836 for (raw = f->inocache->nodes; raw != (void *)f->inocache; raw = raw->next_in_ino) { 837 838 /* We only care about obsolete ones */ 839 if (!(ref_obsolete(raw))) 840 continue; 841 842 /* Any dirent with the same name is going to have the same length... */ 843 if (ref_totlen(c, NULL, raw) != rawlen) 844 continue; 845 846 /* Doesn't matter if there's one in the same erase block. We're going to 847 delete it too at the same time. */ 848 if (SECTOR_ADDR(raw->flash_offset) == SECTOR_ADDR(fd->raw->flash_offset)) 849 continue; 850 851 D1(printk(KERN_DEBUG "Check potential deletion dirent at %08x\n", ref_offset(raw))); 852 853 /* This is an obsolete node belonging to the same directory, and it's of the right 854 length. We need to take a closer look...*/ 855 ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)rd); 856 if (ret) { 857 printk(KERN_WARNING "jffs2_g_c_deletion_dirent(): Read error (%d) reading obsolete node at %08x\n", ret, ref_offset(raw)); 858 /* If we can't read it, we don't need to continue to obsolete it. Continue */ 859 continue; 860 } 861 if (retlen != rawlen) { 862 printk(KERN_WARNING "jffs2_g_c_deletion_dirent(): Short read (%zd not %u) reading header from obsolete node at %08x\n", 863 retlen, rawlen, ref_offset(raw)); 864 continue; 865 } 866 867 if (je16_to_cpu(rd->nodetype) != JFFS2_NODETYPE_DIRENT) 868 continue; 869 870 /* If the name CRC doesn't match, skip */ 871 if (je32_to_cpu(rd->name_crc) != name_crc) 872 continue; 873 874 /* If the name length doesn't match, or it's another deletion dirent, skip */ 875 if (rd->nsize != name_len || !je32_to_cpu(rd->ino)) 876 continue; 877 878 /* OK, check the actual name now */ 879 if (memcmp(rd->name, fd->name, name_len)) 880 continue; 881 882 /* OK. The name really does match. There really is still an older node on 883 the flash which our deletion dirent obsoletes. So we have to write out 884 a new deletion dirent to replace it */ 885 up(&c->erase_free_sem); 886 887 D1(printk(KERN_DEBUG "Deletion dirent at %08x still obsoletes real dirent \"%s\" at %08x for ino #%u\n", 888 ref_offset(fd->raw), fd->name, ref_offset(raw), je32_to_cpu(rd->ino))); 889 kfree(rd); 890 891 return jffs2_garbage_collect_dirent(c, jeb, f, fd); 892 } 893 894 up(&c->erase_free_sem); 895 kfree(rd); 896 } 897 898 /* FIXME: If we're deleting a dirent which contains the current mtime and ctime, 899 we should update the metadata node with those times accordingly */ 900 901 /* No need for it any more. Just mark it obsolete and remove it from the list */ 902 while (*fdp) { 903 if ((*fdp) == fd) { 904 found = 1; 905 *fdp = fd->next; 906 break; 907 } 908 fdp = &(*fdp)->next; 909 } 910 if (!found) { 911 printk(KERN_WARNING "Deletion dirent \"%s\" not found in list for ino #%u\n", fd->name, f->inocache->ino); 912 } 913 jffs2_mark_node_obsolete(c, fd->raw); 914 jffs2_free_full_dirent(fd); 915 return 0; 916 } 917 918 static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 919 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 920 uint32_t start, uint32_t end) 921 { 922 struct jffs2_raw_inode ri; 923 struct jffs2_node_frag *frag; 924 struct jffs2_full_dnode *new_fn; 925 uint32_t alloclen, phys_ofs, ilen; 926 int ret; 927 928 D1(printk(KERN_DEBUG "Writing replacement hole node for ino #%u from offset 0x%x to 0x%x\n", 929 f->inocache->ino, start, end)); 930 931 memset(&ri, 0, sizeof(ri)); 932 933 if(fn->frags > 1) { 934 size_t readlen; 935 uint32_t crc; 936 /* It's partially obsoleted by a later write. So we have to 937 write it out again with the _same_ version as before */ 938 ret = jffs2_flash_read(c, ref_offset(fn->raw), sizeof(ri), &readlen, (char *)&ri); 939 if (readlen != sizeof(ri) || ret) { 940 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); 941 goto fill; 942 } 943 if (je16_to_cpu(ri.nodetype) != JFFS2_NODETYPE_INODE) { 944 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node at 0x%08x had node type 0x%04x instead of JFFS2_NODETYPE_INODE(0x%04x)\n", 945 ref_offset(fn->raw), 946 je16_to_cpu(ri.nodetype), JFFS2_NODETYPE_INODE); 947 return -EIO; 948 } 949 if (je32_to_cpu(ri.totlen) != sizeof(ri)) { 950 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node at 0x%08x had totlen 0x%x instead of expected 0x%zx\n", 951 ref_offset(fn->raw), 952 je32_to_cpu(ri.totlen), sizeof(ri)); 953 return -EIO; 954 } 955 crc = crc32(0, &ri, sizeof(ri)-8); 956 if (crc != je32_to_cpu(ri.node_crc)) { 957 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node at 0x%08x had CRC 0x%08x which doesn't match calculated CRC 0x%08x\n", 958 ref_offset(fn->raw), 959 je32_to_cpu(ri.node_crc), crc); 960 /* FIXME: We could possibly deal with this by writing new holes for each frag */ 961 printk(KERN_WARNING "Data in the range 0x%08x to 0x%08x of inode #%u will be lost\n", 962 start, end, f->inocache->ino); 963 goto fill; 964 } 965 if (ri.compr != JFFS2_COMPR_ZERO) { 966 printk(KERN_WARNING "jffs2_garbage_collect_hole: Node 0x%08x wasn't a hole node!\n", ref_offset(fn->raw)); 967 printk(KERN_WARNING "Data in the range 0x%08x to 0x%08x of inode #%u will be lost\n", 968 start, end, f->inocache->ino); 969 goto fill; 970 } 971 } else { 972 fill: 973 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 974 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 975 ri.totlen = cpu_to_je32(sizeof(ri)); 976 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 977 978 ri.ino = cpu_to_je32(f->inocache->ino); 979 ri.version = cpu_to_je32(++f->highest_version); 980 ri.offset = cpu_to_je32(start); 981 ri.dsize = cpu_to_je32(end - start); 982 ri.csize = cpu_to_je32(0); 983 ri.compr = JFFS2_COMPR_ZERO; 984 } 985 986 frag = frag_last(&f->fragtree); 987 if (frag) 988 /* Fetch the inode length from the fragtree rather then 989 * from i_size since i_size may have not been updated yet */ 990 ilen = frag->ofs + frag->size; 991 else 992 ilen = JFFS2_F_I_SIZE(f); 993 994 ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f)); 995 ri.uid = cpu_to_je16(JFFS2_F_I_UID(f)); 996 ri.gid = cpu_to_je16(JFFS2_F_I_GID(f)); 997 ri.isize = cpu_to_je32(ilen); 998 ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f)); 999 ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f)); 1000 ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 1001 ri.data_crc = cpu_to_je32(0); 1002 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1003 1004 ret = jffs2_reserve_space_gc(c, sizeof(ri), &phys_ofs, &alloclen, 1005 JFFS2_SUMMARY_INODE_SIZE); 1006 if (ret) { 1007 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_hole failed: %d\n", 1008 sizeof(ri), ret); 1009 return ret; 1010 } 1011 new_fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_GC); 1012 1013 if (IS_ERR(new_fn)) { 1014 printk(KERN_WARNING "Error writing new hole node: %ld\n", PTR_ERR(new_fn)); 1015 return PTR_ERR(new_fn); 1016 } 1017 if (je32_to_cpu(ri.version) == f->highest_version) { 1018 jffs2_add_full_dnode_to_inode(c, f, new_fn); 1019 if (f->metadata) { 1020 jffs2_mark_node_obsolete(c, f->metadata->raw); 1021 jffs2_free_full_dnode(f->metadata); 1022 f->metadata = NULL; 1023 } 1024 return 0; 1025 } 1026 1027 /* 1028 * We should only get here in the case where the node we are 1029 * replacing had more than one frag, so we kept the same version 1030 * number as before. (Except in case of error -- see 'goto fill;' 1031 * above.) 1032 */ 1033 D1(if(unlikely(fn->frags <= 1)) { 1034 printk(KERN_WARNING "jffs2_garbage_collect_hole: Replacing fn with %d frag(s) but new ver %d != highest_version %d of ino #%d\n", 1035 fn->frags, je32_to_cpu(ri.version), f->highest_version, 1036 je32_to_cpu(ri.ino)); 1037 }); 1038 1039 /* This is a partially-overlapped hole node. Mark it REF_NORMAL not REF_PRISTINE */ 1040 mark_ref_normal(new_fn->raw); 1041 1042 for (frag = jffs2_lookup_node_frag(&f->fragtree, fn->ofs); 1043 frag; frag = frag_next(frag)) { 1044 if (frag->ofs > fn->size + fn->ofs) 1045 break; 1046 if (frag->node == fn) { 1047 frag->node = new_fn; 1048 new_fn->frags++; 1049 fn->frags--; 1050 } 1051 } 1052 if (fn->frags) { 1053 printk(KERN_WARNING "jffs2_garbage_collect_hole: Old node still has frags!\n"); 1054 BUG(); 1055 } 1056 if (!new_fn->frags) { 1057 printk(KERN_WARNING "jffs2_garbage_collect_hole: New node has no frags!\n"); 1058 BUG(); 1059 } 1060 1061 jffs2_mark_node_obsolete(c, fn->raw); 1062 jffs2_free_full_dnode(fn); 1063 1064 return 0; 1065 } 1066 1067 static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 1068 struct jffs2_inode_info *f, struct jffs2_full_dnode *fn, 1069 uint32_t start, uint32_t end) 1070 { 1071 struct jffs2_full_dnode *new_fn; 1072 struct jffs2_raw_inode ri; 1073 uint32_t alloclen, phys_ofs, offset, orig_end, orig_start; 1074 int ret = 0; 1075 unsigned char *comprbuf = NULL, *writebuf; 1076 unsigned long pg; 1077 unsigned char *pg_ptr; 1078 1079 memset(&ri, 0, sizeof(ri)); 1080 1081 D1(printk(KERN_DEBUG "Writing replacement dnode for ino #%u from offset 0x%x to 0x%x\n", 1082 f->inocache->ino, start, end)); 1083 1084 orig_end = end; 1085 orig_start = start; 1086 1087 if (c->nr_free_blocks + c->nr_erasing_blocks > c->resv_blocks_gcmerge) { 1088 /* Attempt to do some merging. But only expand to cover logically 1089 adjacent frags if the block containing them is already considered 1090 to be dirty. Otherwise we end up with GC just going round in 1091 circles dirtying the nodes it already wrote out, especially 1092 on NAND where we have small eraseblocks and hence a much higher 1093 chance of nodes having to be split to cross boundaries. */ 1094 1095 struct jffs2_node_frag *frag; 1096 uint32_t min, max; 1097 1098 min = start & ~(PAGE_CACHE_SIZE-1); 1099 max = min + PAGE_CACHE_SIZE; 1100 1101 frag = jffs2_lookup_node_frag(&f->fragtree, start); 1102 1103 /* BUG_ON(!frag) but that'll happen anyway... */ 1104 1105 BUG_ON(frag->ofs != start); 1106 1107 /* First grow down... */ 1108 while((frag = frag_prev(frag)) && frag->ofs >= min) { 1109 1110 /* If the previous frag doesn't even reach the beginning, there's 1111 excessive fragmentation. Just merge. */ 1112 if (frag->ofs > min) { 1113 D1(printk(KERN_DEBUG "Expanding down to cover partial frag (0x%x-0x%x)\n", 1114 frag->ofs, frag->ofs+frag->size)); 1115 start = frag->ofs; 1116 continue; 1117 } 1118 /* OK. This frag holds the first byte of the page. */ 1119 if (!frag->node || !frag->node->raw) { 1120 D1(printk(KERN_DEBUG "First frag in page is hole (0x%x-0x%x). Not expanding down.\n", 1121 frag->ofs, frag->ofs+frag->size)); 1122 break; 1123 } else { 1124 1125 /* OK, it's a frag which extends to the beginning of the page. Does it live 1126 in a block which is still considered clean? If so, don't obsolete it. 1127 If not, cover it anyway. */ 1128 1129 struct jffs2_raw_node_ref *raw = frag->node->raw; 1130 struct jffs2_eraseblock *jeb; 1131 1132 jeb = &c->blocks[raw->flash_offset / c->sector_size]; 1133 1134 if (jeb == c->gcblock) { 1135 D1(printk(KERN_DEBUG "Expanding down to cover frag (0x%x-0x%x) in gcblock at %08x\n", 1136 frag->ofs, frag->ofs+frag->size, ref_offset(raw))); 1137 start = frag->ofs; 1138 break; 1139 } 1140 if (!ISDIRTY(jeb->dirty_size + jeb->wasted_size)) { 1141 D1(printk(KERN_DEBUG "Not expanding down to cover frag (0x%x-0x%x) in clean block %08x\n", 1142 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1143 break; 1144 } 1145 1146 D1(printk(KERN_DEBUG "Expanding down to cover frag (0x%x-0x%x) in dirty block %08x\n", 1147 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1148 start = frag->ofs; 1149 break; 1150 } 1151 } 1152 1153 /* ... then up */ 1154 1155 /* Find last frag which is actually part of the node we're to GC. */ 1156 frag = jffs2_lookup_node_frag(&f->fragtree, end-1); 1157 1158 while((frag = frag_next(frag)) && frag->ofs+frag->size <= max) { 1159 1160 /* If the previous frag doesn't even reach the beginning, there's lots 1161 of fragmentation. Just merge. */ 1162 if (frag->ofs+frag->size < max) { 1163 D1(printk(KERN_DEBUG "Expanding up to cover partial frag (0x%x-0x%x)\n", 1164 frag->ofs, frag->ofs+frag->size)); 1165 end = frag->ofs + frag->size; 1166 continue; 1167 } 1168 1169 if (!frag->node || !frag->node->raw) { 1170 D1(printk(KERN_DEBUG "Last frag in page is hole (0x%x-0x%x). Not expanding up.\n", 1171 frag->ofs, frag->ofs+frag->size)); 1172 break; 1173 } else { 1174 1175 /* OK, it's a frag which extends to the beginning of the page. Does it live 1176 in a block which is still considered clean? If so, don't obsolete it. 1177 If not, cover it anyway. */ 1178 1179 struct jffs2_raw_node_ref *raw = frag->node->raw; 1180 struct jffs2_eraseblock *jeb; 1181 1182 jeb = &c->blocks[raw->flash_offset / c->sector_size]; 1183 1184 if (jeb == c->gcblock) { 1185 D1(printk(KERN_DEBUG "Expanding up to cover frag (0x%x-0x%x) in gcblock at %08x\n", 1186 frag->ofs, frag->ofs+frag->size, ref_offset(raw))); 1187 end = frag->ofs + frag->size; 1188 break; 1189 } 1190 if (!ISDIRTY(jeb->dirty_size + jeb->wasted_size)) { 1191 D1(printk(KERN_DEBUG "Not expanding up to cover frag (0x%x-0x%x) in clean block %08x\n", 1192 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1193 break; 1194 } 1195 1196 D1(printk(KERN_DEBUG "Expanding up to cover frag (0x%x-0x%x) in dirty block %08x\n", 1197 frag->ofs, frag->ofs+frag->size, jeb->offset)); 1198 end = frag->ofs + frag->size; 1199 break; 1200 } 1201 } 1202 D1(printk(KERN_DEBUG "Expanded dnode to write from (0x%x-0x%x) to (0x%x-0x%x)\n", 1203 orig_start, orig_end, start, end)); 1204 1205 D1(BUG_ON(end > frag_last(&f->fragtree)->ofs + frag_last(&f->fragtree)->size)); 1206 BUG_ON(end < orig_end); 1207 BUG_ON(start > orig_start); 1208 } 1209 1210 /* First, use readpage() to read the appropriate page into the page cache */ 1211 /* Q: What happens if we actually try to GC the _same_ page for which commit_write() 1212 * triggered garbage collection in the first place? 1213 * A: I _think_ it's OK. read_cache_page shouldn't deadlock, we'll write out the 1214 * page OK. We'll actually write it out again in commit_write, which is a little 1215 * suboptimal, but at least we're correct. 1216 */ 1217 pg_ptr = jffs2_gc_fetch_page(c, f, start, &pg); 1218 1219 if (IS_ERR(pg_ptr)) { 1220 printk(KERN_WARNING "read_cache_page() returned error: %ld\n", PTR_ERR(pg_ptr)); 1221 return PTR_ERR(pg_ptr); 1222 } 1223 1224 offset = start; 1225 while(offset < orig_end) { 1226 uint32_t datalen; 1227 uint32_t cdatalen; 1228 uint16_t comprtype = JFFS2_COMPR_NONE; 1229 1230 ret = jffs2_reserve_space_gc(c, sizeof(ri) + JFFS2_MIN_DATA_LEN, &phys_ofs, 1231 &alloclen, JFFS2_SUMMARY_INODE_SIZE); 1232 1233 if (ret) { 1234 printk(KERN_WARNING "jffs2_reserve_space_gc of %zd bytes for garbage_collect_dnode failed: %d\n", 1235 sizeof(ri)+ JFFS2_MIN_DATA_LEN, ret); 1236 break; 1237 } 1238 cdatalen = min_t(uint32_t, alloclen - sizeof(ri), end - offset); 1239 datalen = end - offset; 1240 1241 writebuf = pg_ptr + (offset & (PAGE_CACHE_SIZE -1)); 1242 1243 comprtype = jffs2_compress(c, f, writebuf, &comprbuf, &datalen, &cdatalen); 1244 1245 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1246 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1247 ri.totlen = cpu_to_je32(sizeof(ri) + cdatalen); 1248 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1249 1250 ri.ino = cpu_to_je32(f->inocache->ino); 1251 ri.version = cpu_to_je32(++f->highest_version); 1252 ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f)); 1253 ri.uid = cpu_to_je16(JFFS2_F_I_UID(f)); 1254 ri.gid = cpu_to_je16(JFFS2_F_I_GID(f)); 1255 ri.isize = cpu_to_je32(JFFS2_F_I_SIZE(f)); 1256 ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f)); 1257 ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f)); 1258 ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f)); 1259 ri.offset = cpu_to_je32(offset); 1260 ri.csize = cpu_to_je32(cdatalen); 1261 ri.dsize = cpu_to_je32(datalen); 1262 ri.compr = comprtype & 0xff; 1263 ri.usercompr = (comprtype >> 8) & 0xff; 1264 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1265 ri.data_crc = cpu_to_je32(crc32(0, comprbuf, cdatalen)); 1266 1267 new_fn = jffs2_write_dnode(c, f, &ri, comprbuf, cdatalen, phys_ofs, ALLOC_GC); 1268 1269 jffs2_free_comprbuf(comprbuf, writebuf); 1270 1271 if (IS_ERR(new_fn)) { 1272 printk(KERN_WARNING "Error writing new dnode: %ld\n", PTR_ERR(new_fn)); 1273 ret = PTR_ERR(new_fn); 1274 break; 1275 } 1276 ret = jffs2_add_full_dnode_to_inode(c, f, new_fn); 1277 offset += datalen; 1278 if (f->metadata) { 1279 jffs2_mark_node_obsolete(c, f->metadata->raw); 1280 jffs2_free_full_dnode(f->metadata); 1281 f->metadata = NULL; 1282 } 1283 } 1284 1285 jffs2_gc_release_page(c, pg_ptr, &pg); 1286 return ret; 1287 } 1288