xref: /openbmc/linux/fs/jffs2/write.c (revision 43dfa07f)
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/fs.h>
14 #include <linux/crc32.h>
15 #include <linux/slab.h>
16 #include <linux/pagemap.h>
17 #include <linux/mtd/mtd.h>
18 #include "nodelist.h"
19 #include "compr.h"
20 
21 
22 int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri)
23 {
24 	struct jffs2_inode_cache *ic;
25 
26 	ic = jffs2_alloc_inode_cache();
27 	if (!ic) {
28 		return -ENOMEM;
29 	}
30 
31 	memset(ic, 0, sizeof(*ic));
32 
33 	f->inocache = ic;
34 	f->inocache->nlink = 1;
35 	f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache;
36 	f->inocache->state = INO_STATE_PRESENT;
37 
38 	jffs2_add_ino_cache(c, f->inocache);
39 	D1(printk(KERN_DEBUG "jffs2_do_new_inode(): Assigned ino# %d\n", f->inocache->ino));
40 	ri->ino = cpu_to_je32(f->inocache->ino);
41 
42 	ri->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
43 	ri->nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
44 	ri->totlen = cpu_to_je32(PAD(sizeof(*ri)));
45 	ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
46 	ri->mode = cpu_to_jemode(mode);
47 
48 	f->highest_version = 1;
49 	ri->version = cpu_to_je32(f->highest_version);
50 
51 	return 0;
52 }
53 
54 /* jffs2_write_dnode - given a raw_inode, allocate a full_dnode for it,
55    write it to the flash, link it into the existing inode/fragment list */
56 
57 struct jffs2_full_dnode *jffs2_write_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
58 					   struct jffs2_raw_inode *ri, const unsigned char *data,
59 					   uint32_t datalen, int alloc_mode)
60 
61 {
62 	struct jffs2_full_dnode *fn;
63 	size_t retlen;
64 	uint32_t flash_ofs;
65 	struct kvec vecs[2];
66 	int ret;
67 	int retried = 0;
68 	unsigned long cnt = 2;
69 
70 	D1(if(je32_to_cpu(ri->hdr_crc) != crc32(0, ri, sizeof(struct jffs2_unknown_node)-4)) {
71 		printk(KERN_CRIT "Eep. CRC not correct in jffs2_write_dnode()\n");
72 		BUG();
73 	}
74 	   );
75 	vecs[0].iov_base = ri;
76 	vecs[0].iov_len = sizeof(*ri);
77 	vecs[1].iov_base = (unsigned char *)data;
78 	vecs[1].iov_len = datalen;
79 
80 	if (je32_to_cpu(ri->totlen) != sizeof(*ri) + datalen) {
81 		printk(KERN_WARNING "jffs2_write_dnode: ri->totlen (0x%08x) != sizeof(*ri) (0x%08zx) + datalen (0x%08x)\n", je32_to_cpu(ri->totlen), sizeof(*ri), datalen);
82 	}
83 
84 	fn = jffs2_alloc_full_dnode();
85 	if (!fn)
86 		return ERR_PTR(-ENOMEM);
87 
88 	/* check number of valid vecs */
89 	if (!datalen || !data)
90 		cnt = 1;
91  retry:
92 	flash_ofs = write_ofs(c);
93 
94 	jffs2_dbg_prewrite_paranoia_check(c, flash_ofs, vecs[0].iov_len + vecs[1].iov_len);
95 
96 	if ((alloc_mode!=ALLOC_GC) && (je32_to_cpu(ri->version) < f->highest_version)) {
97 		BUG_ON(!retried);
98 		D1(printk(KERN_DEBUG "jffs2_write_dnode : dnode_version %d, "
99 				"highest version %d -> updating dnode\n",
100 				je32_to_cpu(ri->version), f->highest_version));
101 		ri->version = cpu_to_je32(++f->highest_version);
102 		ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
103 	}
104 
105 	ret = jffs2_flash_writev(c, vecs, cnt, flash_ofs, &retlen,
106 				 (alloc_mode==ALLOC_GC)?0:f->inocache->ino);
107 
108 	if (ret || (retlen != sizeof(*ri) + datalen)) {
109 		printk(KERN_NOTICE "Write of %zd bytes at 0x%08x failed. returned %d, retlen %zd\n",
110 		       sizeof(*ri)+datalen, flash_ofs, ret, retlen);
111 
112 		/* Mark the space as dirtied */
113 		if (retlen) {
114 			/* Don't change raw->size to match retlen. We may have
115 			   written the node header already, and only the data will
116 			   seem corrupted, in which case the scan would skip over
117 			   any node we write before the original intended end of
118 			   this node */
119 			jffs2_add_physical_node_ref(c, flash_ofs | REF_OBSOLETE, PAD(sizeof(*ri)+datalen), NULL);
120 		} else {
121 			printk(KERN_NOTICE "Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n", flash_ofs);
122 		}
123 		if (!retried && alloc_mode != ALLOC_NORETRY) {
124 			/* Try to reallocate space and retry */
125 			uint32_t dummy;
126 			struct jffs2_eraseblock *jeb = &c->blocks[flash_ofs / c->sector_size];
127 
128 			retried = 1;
129 
130 			D1(printk(KERN_DEBUG "Retrying failed write.\n"));
131 
132 			jffs2_dbg_acct_sanity_check(c,jeb);
133 			jffs2_dbg_acct_paranoia_check(c, jeb);
134 
135 			if (alloc_mode == ALLOC_GC) {
136 				ret = jffs2_reserve_space_gc(c, sizeof(*ri) + datalen, &dummy,
137 							     JFFS2_SUMMARY_INODE_SIZE);
138 			} else {
139 				/* Locking pain */
140 				up(&f->sem);
141 				jffs2_complete_reservation(c);
142 
143 				ret = jffs2_reserve_space(c, sizeof(*ri) + datalen, &dummy,
144 							  alloc_mode, JFFS2_SUMMARY_INODE_SIZE);
145 				down(&f->sem);
146 			}
147 
148 			if (!ret) {
149 				flash_ofs = write_ofs(c);
150 				D1(printk(KERN_DEBUG "Allocated space at 0x%08x to retry failed write.\n", flash_ofs));
151 
152 				jffs2_dbg_acct_sanity_check(c,jeb);
153 				jffs2_dbg_acct_paranoia_check(c, jeb);
154 
155 				goto retry;
156 			}
157 			D1(printk(KERN_DEBUG "Failed to allocate space to retry failed write: %d!\n", ret));
158 		}
159 		/* Release the full_dnode which is now useless, and return */
160 		jffs2_free_full_dnode(fn);
161 		return ERR_PTR(ret?ret:-EIO);
162 	}
163 	/* Mark the space used */
164 	/* If node covers at least a whole page, or if it starts at the
165 	   beginning of a page and runs to the end of the file, or if
166 	   it's a hole node, mark it REF_PRISTINE, else REF_NORMAL.
167 	*/
168 	if ((je32_to_cpu(ri->dsize) >= PAGE_CACHE_SIZE) ||
169 	    ( ((je32_to_cpu(ri->offset)&(PAGE_CACHE_SIZE-1))==0) &&
170 	      (je32_to_cpu(ri->dsize)+je32_to_cpu(ri->offset) ==  je32_to_cpu(ri->isize)))) {
171 		flash_ofs |= REF_PRISTINE;
172 	} else {
173 		flash_ofs |= REF_NORMAL;
174 	}
175 	fn->raw = jffs2_add_physical_node_ref(c, flash_ofs, PAD(sizeof(*ri)+datalen), f->inocache);
176 	if (IS_ERR(fn->raw)) {
177 		void *hold_err = fn->raw;
178 		/* Release the full_dnode which is now useless, and return */
179 		jffs2_free_full_dnode(fn);
180 		return ERR_PTR(PTR_ERR(hold_err));
181 	}
182 	fn->ofs = je32_to_cpu(ri->offset);
183 	fn->size = je32_to_cpu(ri->dsize);
184 	fn->frags = 0;
185 
186 	D1(printk(KERN_DEBUG "jffs2_write_dnode wrote node at 0x%08x(%d) with dsize 0x%x, csize 0x%x, node_crc 0x%08x, data_crc 0x%08x, totlen 0x%08x\n",
187 		  flash_ofs & ~3, flash_ofs & 3, je32_to_cpu(ri->dsize),
188 		  je32_to_cpu(ri->csize), je32_to_cpu(ri->node_crc),
189 		  je32_to_cpu(ri->data_crc), je32_to_cpu(ri->totlen)));
190 
191 	if (retried) {
192 		jffs2_dbg_acct_sanity_check(c,NULL);
193 	}
194 
195 	return fn;
196 }
197 
198 struct jffs2_full_dirent *jffs2_write_dirent(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
199 					     struct jffs2_raw_dirent *rd, const unsigned char *name,
200 					     uint32_t namelen, int alloc_mode)
201 {
202 	struct jffs2_full_dirent *fd;
203 	size_t retlen;
204 	struct kvec vecs[2];
205 	uint32_t flash_ofs;
206 	int retried = 0;
207 	int ret;
208 
209 	D1(printk(KERN_DEBUG "jffs2_write_dirent(ino #%u, name at *0x%p \"%s\"->ino #%u, name_crc 0x%08x)\n",
210 		  je32_to_cpu(rd->pino), name, name, je32_to_cpu(rd->ino),
211 		  je32_to_cpu(rd->name_crc)));
212 
213 	D1(if(je32_to_cpu(rd->hdr_crc) != crc32(0, rd, sizeof(struct jffs2_unknown_node)-4)) {
214 		printk(KERN_CRIT "Eep. CRC not correct in jffs2_write_dirent()\n");
215 		BUG();
216 	   });
217 
218 	vecs[0].iov_base = rd;
219 	vecs[0].iov_len = sizeof(*rd);
220 	vecs[1].iov_base = (unsigned char *)name;
221 	vecs[1].iov_len = namelen;
222 
223 	fd = jffs2_alloc_full_dirent(namelen+1);
224 	if (!fd)
225 		return ERR_PTR(-ENOMEM);
226 
227 	fd->version = je32_to_cpu(rd->version);
228 	fd->ino = je32_to_cpu(rd->ino);
229 	fd->nhash = full_name_hash(name, strlen(name));
230 	fd->type = rd->type;
231 	memcpy(fd->name, name, namelen);
232 	fd->name[namelen]=0;
233 
234  retry:
235 	flash_ofs = write_ofs(c);
236 
237 	jffs2_dbg_prewrite_paranoia_check(c, flash_ofs, vecs[0].iov_len + vecs[1].iov_len);
238 
239 	if ((alloc_mode!=ALLOC_GC) && (je32_to_cpu(rd->version) < f->highest_version)) {
240 		BUG_ON(!retried);
241 		D1(printk(KERN_DEBUG "jffs2_write_dirent : dirent_version %d, "
242 				     "highest version %d -> updating dirent\n",
243 				     je32_to_cpu(rd->version), f->highest_version));
244 		rd->version = cpu_to_je32(++f->highest_version);
245 		fd->version = je32_to_cpu(rd->version);
246 		rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
247 	}
248 
249 	ret = jffs2_flash_writev(c, vecs, 2, flash_ofs, &retlen,
250 				 (alloc_mode==ALLOC_GC)?0:je32_to_cpu(rd->pino));
251 	if (ret || (retlen != sizeof(*rd) + namelen)) {
252 		printk(KERN_NOTICE "Write of %zd bytes at 0x%08x failed. returned %d, retlen %zd\n",
253 			       sizeof(*rd)+namelen, flash_ofs, ret, retlen);
254 		/* Mark the space as dirtied */
255 		if (retlen) {
256 			jffs2_add_physical_node_ref(c, flash_ofs | REF_OBSOLETE, PAD(sizeof(*rd)+namelen), NULL);
257 		} else {
258 			printk(KERN_NOTICE "Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n", flash_ofs);
259 		}
260 		if (!retried) {
261 			/* Try to reallocate space and retry */
262 			uint32_t dummy;
263 			struct jffs2_eraseblock *jeb = &c->blocks[flash_ofs / c->sector_size];
264 
265 			retried = 1;
266 
267 			D1(printk(KERN_DEBUG "Retrying failed write.\n"));
268 
269 			jffs2_dbg_acct_sanity_check(c,jeb);
270 			jffs2_dbg_acct_paranoia_check(c, jeb);
271 
272 			if (alloc_mode == ALLOC_GC) {
273 				ret = jffs2_reserve_space_gc(c, sizeof(*rd) + namelen, &dummy,
274 							     JFFS2_SUMMARY_DIRENT_SIZE(namelen));
275 			} else {
276 				/* Locking pain */
277 				up(&f->sem);
278 				jffs2_complete_reservation(c);
279 
280 				ret = jffs2_reserve_space(c, sizeof(*rd) + namelen, &dummy,
281 							  alloc_mode, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
282 				down(&f->sem);
283 			}
284 
285 			if (!ret) {
286 				flash_ofs = write_ofs(c);
287 				D1(printk(KERN_DEBUG "Allocated space at 0x%08x to retry failed write.\n", flash_ofs));
288 				jffs2_dbg_acct_sanity_check(c,jeb);
289 				jffs2_dbg_acct_paranoia_check(c, jeb);
290 				goto retry;
291 			}
292 			D1(printk(KERN_DEBUG "Failed to allocate space to retry failed write: %d!\n", ret));
293 		}
294 		/* Release the full_dnode which is now useless, and return */
295 		jffs2_free_full_dirent(fd);
296 		return ERR_PTR(ret?ret:-EIO);
297 	}
298 	/* Mark the space used */
299 	fd->raw = jffs2_add_physical_node_ref(c, flash_ofs | dirent_node_state(rd),
300 					      PAD(sizeof(*rd)+namelen), f->inocache);
301 	if (IS_ERR(fd->raw)) {
302 		void *hold_err = fd->raw;
303 		/* Release the full_dirent which is now useless, and return */
304 		jffs2_free_full_dirent(fd);
305 		return ERR_PTR(PTR_ERR(hold_err));
306 	}
307 
308 	if (retried) {
309 		jffs2_dbg_acct_sanity_check(c,NULL);
310 	}
311 
312 	return fd;
313 }
314 
315 /* The OS-specific code fills in the metadata in the jffs2_raw_inode for us, so that
316    we don't have to go digging in struct inode or its equivalent. It should set:
317    mode, uid, gid, (starting)isize, atime, ctime, mtime */
318 int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
319 			    struct jffs2_raw_inode *ri, unsigned char *buf,
320 			    uint32_t offset, uint32_t writelen, uint32_t *retlen)
321 {
322 	int ret = 0;
323 	uint32_t writtenlen = 0;
324 
325        	D1(printk(KERN_DEBUG "jffs2_write_inode_range(): Ino #%u, ofs 0x%x, len 0x%x\n",
326 		  f->inocache->ino, offset, writelen));
327 
328 	while(writelen) {
329 		struct jffs2_full_dnode *fn;
330 		unsigned char *comprbuf = NULL;
331 		uint16_t comprtype = JFFS2_COMPR_NONE;
332 		uint32_t alloclen;
333 		uint32_t datalen, cdatalen;
334 		int retried = 0;
335 
336 	retry:
337 		D2(printk(KERN_DEBUG "jffs2_commit_write() loop: 0x%x to write to 0x%x\n", writelen, offset));
338 
339 		ret = jffs2_reserve_space(c, sizeof(*ri) + JFFS2_MIN_DATA_LEN,
340 					&alloclen, ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
341 		if (ret) {
342 			D1(printk(KERN_DEBUG "jffs2_reserve_space returned %d\n", ret));
343 			break;
344 		}
345 		down(&f->sem);
346 		datalen = min_t(uint32_t, writelen, PAGE_CACHE_SIZE - (offset & (PAGE_CACHE_SIZE-1)));
347 		cdatalen = min_t(uint32_t, alloclen - sizeof(*ri), datalen);
348 
349 		comprtype = jffs2_compress(c, f, buf, &comprbuf, &datalen, &cdatalen);
350 
351 		ri->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
352 		ri->nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
353 		ri->totlen = cpu_to_je32(sizeof(*ri) + cdatalen);
354 		ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
355 
356 		ri->ino = cpu_to_je32(f->inocache->ino);
357 		ri->version = cpu_to_je32(++f->highest_version);
358 		ri->isize = cpu_to_je32(max(je32_to_cpu(ri->isize), offset + datalen));
359 		ri->offset = cpu_to_je32(offset);
360 		ri->csize = cpu_to_je32(cdatalen);
361 		ri->dsize = cpu_to_je32(datalen);
362 		ri->compr = comprtype & 0xff;
363 		ri->usercompr = (comprtype >> 8 ) & 0xff;
364 		ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
365 		ri->data_crc = cpu_to_je32(crc32(0, comprbuf, cdatalen));
366 
367 		fn = jffs2_write_dnode(c, f, ri, comprbuf, cdatalen, ALLOC_NORETRY);
368 
369 		jffs2_free_comprbuf(comprbuf, buf);
370 
371 		if (IS_ERR(fn)) {
372 			ret = PTR_ERR(fn);
373 			up(&f->sem);
374 			jffs2_complete_reservation(c);
375 			if (!retried) {
376 				/* Write error to be retried */
377 				retried = 1;
378 				D1(printk(KERN_DEBUG "Retrying node write in jffs2_write_inode_range()\n"));
379 				goto retry;
380 			}
381 			break;
382 		}
383 		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
384 		if (f->metadata) {
385 			jffs2_mark_node_obsolete(c, f->metadata->raw);
386 			jffs2_free_full_dnode(f->metadata);
387 			f->metadata = NULL;
388 		}
389 		if (ret) {
390 			/* Eep */
391 			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in commit_write, returned %d\n", ret));
392 			jffs2_mark_node_obsolete(c, fn->raw);
393 			jffs2_free_full_dnode(fn);
394 
395 			up(&f->sem);
396 			jffs2_complete_reservation(c);
397 			break;
398 		}
399 		up(&f->sem);
400 		jffs2_complete_reservation(c);
401 		if (!datalen) {
402 			printk(KERN_WARNING "Eep. We didn't actually write any data in jffs2_write_inode_range()\n");
403 			ret = -EIO;
404 			break;
405 		}
406 		D1(printk(KERN_DEBUG "increasing writtenlen by %d\n", datalen));
407 		writtenlen += datalen;
408 		offset += datalen;
409 		writelen -= datalen;
410 		buf += datalen;
411 	}
412 	*retlen = writtenlen;
413 	return ret;
414 }
415 
416 int jffs2_do_create(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, struct jffs2_inode_info *f, struct jffs2_raw_inode *ri, const char *name, int namelen)
417 {
418 	struct jffs2_raw_dirent *rd;
419 	struct jffs2_full_dnode *fn;
420 	struct jffs2_full_dirent *fd;
421 	uint32_t alloclen;
422 	int ret;
423 
424 	/* Try to reserve enough space for both node and dirent.
425 	 * Just the node will do for now, though
426 	 */
427 	ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
428 				JFFS2_SUMMARY_INODE_SIZE);
429 	D1(printk(KERN_DEBUG "jffs2_do_create(): reserved 0x%x bytes\n", alloclen));
430 	if (ret) {
431 		up(&f->sem);
432 		return ret;
433 	}
434 
435 	ri->data_crc = cpu_to_je32(0);
436 	ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
437 
438 	fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
439 
440 	D1(printk(KERN_DEBUG "jffs2_do_create created file with mode 0x%x\n",
441 		  jemode_to_cpu(ri->mode)));
442 
443 	if (IS_ERR(fn)) {
444 		D1(printk(KERN_DEBUG "jffs2_write_dnode() failed\n"));
445 		/* Eeek. Wave bye bye */
446 		up(&f->sem);
447 		jffs2_complete_reservation(c);
448 		return PTR_ERR(fn);
449 	}
450 	/* No data here. Only a metadata node, which will be
451 	   obsoleted by the first data write
452 	*/
453 	f->metadata = fn;
454 
455 	up(&f->sem);
456 	jffs2_complete_reservation(c);
457 	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
458 				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
459 
460 	if (ret) {
461 		/* Eep. */
462 		D1(printk(KERN_DEBUG "jffs2_reserve_space() for dirent failed\n"));
463 		return ret;
464 	}
465 
466 	rd = jffs2_alloc_raw_dirent();
467 	if (!rd) {
468 		/* Argh. Now we treat it like a normal delete */
469 		jffs2_complete_reservation(c);
470 		return -ENOMEM;
471 	}
472 
473 	down(&dir_f->sem);
474 
475 	rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
476 	rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
477 	rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
478 	rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
479 
480 	rd->pino = cpu_to_je32(dir_f->inocache->ino);
481 	rd->version = cpu_to_je32(++dir_f->highest_version);
482 	rd->ino = ri->ino;
483 	rd->mctime = ri->ctime;
484 	rd->nsize = namelen;
485 	rd->type = DT_REG;
486 	rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
487 	rd->name_crc = cpu_to_je32(crc32(0, name, namelen));
488 
489 	fd = jffs2_write_dirent(c, dir_f, rd, name, namelen, ALLOC_NORMAL);
490 
491 	jffs2_free_raw_dirent(rd);
492 
493 	if (IS_ERR(fd)) {
494 		/* dirent failed to write. Delete the inode normally
495 		   as if it were the final unlink() */
496 		jffs2_complete_reservation(c);
497 		up(&dir_f->sem);
498 		return PTR_ERR(fd);
499 	}
500 
501 	/* Link the fd into the inode's list, obsoleting an old
502 	   one if necessary. */
503 	jffs2_add_fd_to_list(c, fd, &dir_f->dents);
504 
505 	jffs2_complete_reservation(c);
506 	up(&dir_f->sem);
507 
508 	return 0;
509 }
510 
511 
512 int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f,
513 		    const char *name, int namelen, struct jffs2_inode_info *dead_f,
514 		    uint32_t time)
515 {
516 	struct jffs2_raw_dirent *rd;
517 	struct jffs2_full_dirent *fd;
518 	uint32_t alloclen;
519 	int ret;
520 
521 	if (!jffs2_can_mark_obsolete(c)) {
522 		/* We can't mark stuff obsolete on the medium. We need to write a deletion dirent */
523 
524 		rd = jffs2_alloc_raw_dirent();
525 		if (!rd)
526 			return -ENOMEM;
527 
528 		ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
529 					ALLOC_DELETION, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
530 		if (ret) {
531 			jffs2_free_raw_dirent(rd);
532 			return ret;
533 		}
534 
535 		down(&dir_f->sem);
536 
537 		/* Build a deletion node */
538 		rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
539 		rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
540 		rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
541 		rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
542 
543 		rd->pino = cpu_to_je32(dir_f->inocache->ino);
544 		rd->version = cpu_to_je32(++dir_f->highest_version);
545 		rd->ino = cpu_to_je32(0);
546 		rd->mctime = cpu_to_je32(time);
547 		rd->nsize = namelen;
548 		rd->type = DT_UNKNOWN;
549 		rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
550 		rd->name_crc = cpu_to_je32(crc32(0, name, namelen));
551 
552 		fd = jffs2_write_dirent(c, dir_f, rd, name, namelen, ALLOC_DELETION);
553 
554 		jffs2_free_raw_dirent(rd);
555 
556 		if (IS_ERR(fd)) {
557 			jffs2_complete_reservation(c);
558 			up(&dir_f->sem);
559 			return PTR_ERR(fd);
560 		}
561 
562 		/* File it. This will mark the old one obsolete. */
563 		jffs2_add_fd_to_list(c, fd, &dir_f->dents);
564 		up(&dir_f->sem);
565 	} else {
566 		struct jffs2_full_dirent **prev = &dir_f->dents;
567 		uint32_t nhash = full_name_hash(name, namelen);
568 
569 		down(&dir_f->sem);
570 
571 		while ((*prev) && (*prev)->nhash <= nhash) {
572 			if ((*prev)->nhash == nhash &&
573 			    !memcmp((*prev)->name, name, namelen) &&
574 			    !(*prev)->name[namelen]) {
575 				struct jffs2_full_dirent *this = *prev;
576 
577 				D1(printk(KERN_DEBUG "Marking old dirent node (ino #%u) @%08x obsolete\n",
578 					  this->ino, ref_offset(this->raw)));
579 
580 				*prev = this->next;
581 				jffs2_mark_node_obsolete(c, (this->raw));
582 				jffs2_free_full_dirent(this);
583 				break;
584 			}
585 			prev = &((*prev)->next);
586 		}
587 		up(&dir_f->sem);
588 	}
589 
590 	/* dead_f is NULL if this was a rename not a real unlink */
591 	/* Also catch the !f->inocache case, where there was a dirent
592 	   pointing to an inode which didn't exist. */
593 	if (dead_f && dead_f->inocache) {
594 
595 		down(&dead_f->sem);
596 
597 		if (S_ISDIR(OFNI_EDONI_2SFFJ(dead_f)->i_mode)) {
598 			while (dead_f->dents) {
599 				/* There can be only deleted ones */
600 				fd = dead_f->dents;
601 
602 				dead_f->dents = fd->next;
603 
604 				if (fd->ino) {
605 					printk(KERN_WARNING "Deleting inode #%u with active dentry \"%s\"->ino #%u\n",
606 					       dead_f->inocache->ino, fd->name, fd->ino);
607 				} else {
608 					D1(printk(KERN_DEBUG "Removing deletion dirent for \"%s\" from dir ino #%u\n",
609 						fd->name, dead_f->inocache->ino));
610 				}
611 				jffs2_mark_node_obsolete(c, fd->raw);
612 				jffs2_free_full_dirent(fd);
613 			}
614 		}
615 
616 		dead_f->inocache->nlink--;
617 		/* NB: Caller must set inode nlink if appropriate */
618 		up(&dead_f->sem);
619 	}
620 
621 	jffs2_complete_reservation(c);
622 
623 	return 0;
624 }
625 
626 
627 int jffs2_do_link (struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, uint32_t ino, uint8_t type, const char *name, int namelen, uint32_t time)
628 {
629 	struct jffs2_raw_dirent *rd;
630 	struct jffs2_full_dirent *fd;
631 	uint32_t alloclen;
632 	int ret;
633 
634 	rd = jffs2_alloc_raw_dirent();
635 	if (!rd)
636 		return -ENOMEM;
637 
638 	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
639 				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
640 	if (ret) {
641 		jffs2_free_raw_dirent(rd);
642 		return ret;
643 	}
644 
645 	down(&dir_f->sem);
646 
647 	/* Build a deletion node */
648 	rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
649 	rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
650 	rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
651 	rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
652 
653 	rd->pino = cpu_to_je32(dir_f->inocache->ino);
654 	rd->version = cpu_to_je32(++dir_f->highest_version);
655 	rd->ino = cpu_to_je32(ino);
656 	rd->mctime = cpu_to_je32(time);
657 	rd->nsize = namelen;
658 
659 	rd->type = type;
660 
661 	rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
662 	rd->name_crc = cpu_to_je32(crc32(0, name, namelen));
663 
664 	fd = jffs2_write_dirent(c, dir_f, rd, name, namelen, ALLOC_NORMAL);
665 
666 	jffs2_free_raw_dirent(rd);
667 
668 	if (IS_ERR(fd)) {
669 		jffs2_complete_reservation(c);
670 		up(&dir_f->sem);
671 		return PTR_ERR(fd);
672 	}
673 
674 	/* File it. This will mark the old one obsolete. */
675 	jffs2_add_fd_to_list(c, fd, &dir_f->dents);
676 
677 	jffs2_complete_reservation(c);
678 	up(&dir_f->sem);
679 
680 	return 0;
681 }
682