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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / fs / jffs2 / xattr.c
blob3e93cdd1900552d18e900f3b255eff3d356c6a48
1 /*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2006 NEC Corporation
5 *
6 * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/fs.h>
15 #include <linux/time.h>
16 #include <linux/pagemap.h>
17 #include <linux/highmem.h>
18 #include <linux/crc32.h>
19 #include <linux/jffs2.h>
20 #include <linux/xattr.h>
21 #include <linux/mtd/mtd.h>
22 #include "nodelist.h"
23 /* -------- xdatum related functions ----------------
24 * xattr_datum_hashkey(xprefix, xname, xvalue, xsize)
25 * is used to calcurate xdatum hashkey. The reminder of hashkey into XATTRINDEX_HASHSIZE is
26 * the index of the xattr name/value pair cache (c->xattrindex).
27 * is_xattr_datum_unchecked(c, xd)
28 * returns 1, if xdatum contains any unchecked raw nodes. if all raw nodes are not
29 * unchecked, it returns 0.
30 * unload_xattr_datum(c, xd)
31 * is used to release xattr name/value pair and detach from c->xattrindex.
32 * reclaim_xattr_datum(c)
33 * is used to reclaim xattr name/value pairs on the xattr name/value pair cache when
34 * memory usage by cache is over c->xdatum_mem_threshold. Currently, this threshold
35 * is hard coded as 32KiB.
36 * do_verify_xattr_datum(c, xd)
37 * is used to load the xdatum informations without name/value pair from the medium.
38 * It's necessary once, because those informations are not collected during mounting
39 * process when EBS is enabled.
40 * 0 will be returned, if success. An negative return value means recoverable error, and
41 * positive return value means unrecoverable error. Thus, caller must remove this xdatum
42 * and xref when it returned positive value.
43 * do_load_xattr_datum(c, xd)
44 * is used to load name/value pair from the medium.
45 * The meanings of return value is same as do_verify_xattr_datum().
46 * load_xattr_datum(c, xd)
47 * is used to be as a wrapper of do_verify_xattr_datum() and do_load_xattr_datum().
48 * If xd need to call do_verify_xattr_datum() at first, it's called before calling
49 * do_load_xattr_datum(). The meanings of return value is same as do_verify_xattr_datum().
50 * save_xattr_datum(c, xd)
51 * is used to write xdatum to medium. xd->version will be incremented.
52 * create_xattr_datum(c, xprefix, xname, xvalue, xsize)
53 * is used to create new xdatum and write to medium.
54 * unrefer_xattr_datum(c, xd)
55 * is used to delete a xdatum. When nobody refers this xdatum, JFFS2_XFLAGS_DEAD
56 * is set on xd->flags and chained xattr_dead_list or release it immediately.
57 * In the first case, the garbage collector release it later.
58 * -------------------------------------------------- */
59 static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
60 {
61 int name_len = strlen(xname);
62
63 return crc32(xprefix, xname, name_len) ^ crc32(xprefix, xvalue, xsize);
64 }
65
66 static int is_xattr_datum_unchecked(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
67 {
68 struct jffs2_raw_node_ref *raw;
69 int rc = 0;
70
71 spin_lock(&c->erase_completion_lock);
72 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
73 if (ref_flags(raw) == REF_UNCHECKED) {
74 rc = 1;
75 break;
76 }
77 }
78 spin_unlock(&c->erase_completion_lock);
79 return rc;
80 }
81
82 static void unload_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
83 {
84 /* must be called under down_write(xattr_sem) */
85 D1(dbg_xattr("%s: xid=%u, version=%u\n", __func__, xd->xid, xd->version));
86 if (xd->xname) {
87 c->xdatum_mem_usage -= (xd->name_len + 1 + xd->value_len);
88 kfree(xd->xname);
89 }
90
91 list_del_init(&xd->xindex);
92 xd->hashkey = 0;
93 xd->xname = NULL;
94 xd->xvalue = NULL;
95 }
96
97 static void reclaim_xattr_datum(struct jffs2_sb_info *c)
98 {
99 /* must be called under down_write(xattr_sem) */
100 struct jffs2_xattr_datum *xd, *_xd;
101 uint32_t target, before;
102 static int index = 0;
103 int count;
104
105 if (c->xdatum_mem_threshold > c->xdatum_mem_usage)
106 return;
107
108 before = c->xdatum_mem_usage;
109 target = c->xdatum_mem_usage * 4 / 5; /* 20% reduction */
110 for (count = 0; count < XATTRINDEX_HASHSIZE; count++) {
111 list_for_each_entry_safe(xd, _xd, &c->xattrindex[index], xindex) {
112 if (xd->flags & JFFS2_XFLAGS_HOT) {
113 xd->flags &= ~JFFS2_XFLAGS_HOT;
114 } else if (!(xd->flags & JFFS2_XFLAGS_BIND)) {
115 unload_xattr_datum(c, xd);
116 }
117 if (c->xdatum_mem_usage <= target)
118 goto out;
119 }
120 index = (index+1) % XATTRINDEX_HASHSIZE;
121 }
122 out:
123 JFFS2_NOTICE("xdatum_mem_usage from %u byte to %u byte (%u byte reclaimed)\n",
124 before, c->xdatum_mem_usage, before - c->xdatum_mem_usage);
125 }
126
127 static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
128 {
129 /* must be called under down_write(xattr_sem) */
130 struct jffs2_eraseblock *jeb;
131 struct jffs2_raw_node_ref *raw;
132 struct jffs2_raw_xattr rx;
133 size_t readlen;
134 uint32_t crc, offset, totlen;
135 int rc;
136
137 spin_lock(&c->erase_completion_lock);
138 offset = ref_offset(xd->node);
139 if (ref_flags(xd->node) == REF_PRISTINE)
140 goto complete;
141 spin_unlock(&c->erase_completion_lock);
142
143 rc = jffs2_flash_read(c, offset, sizeof(rx), &readlen, (char *)&rx);
144 if (rc || readlen != sizeof(rx)) {
145 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
146 rc, sizeof(rx), readlen, offset);
147 return rc ? rc : -EIO;
148 }
149 crc = crc32(0, &rx, sizeof(rx) - 4);
150 if (crc != je32_to_cpu(rx.node_crc)) {
151 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
152 offset, je32_to_cpu(rx.hdr_crc), crc);
153 xd->flags |= JFFS2_XFLAGS_INVALID;
154 return -EIO;
155 }
156 totlen = PAD(sizeof(rx) + rx.name_len + 1 + je16_to_cpu(rx.value_len));
157 if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
158 || je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
159 || je32_to_cpu(rx.totlen) != totlen
160 || je32_to_cpu(rx.xid) != xd->xid
161 || je32_to_cpu(rx.version) != xd->version) {
162 JFFS2_ERROR("inconsistent xdatum at %#08x, magic=%#04x/%#04x, "
163 "nodetype=%#04x/%#04x, totlen=%u/%u, xid=%u/%u, version=%u/%u\n",
164 offset, je16_to_cpu(rx.magic), JFFS2_MAGIC_BITMASK,
165 je16_to_cpu(rx.nodetype), JFFS2_NODETYPE_XATTR,
166 je32_to_cpu(rx.totlen), totlen,
167 je32_to_cpu(rx.xid), xd->xid,
168 je32_to_cpu(rx.version), xd->version);
169 xd->flags |= JFFS2_XFLAGS_INVALID;
170 return -EIO;
171 }
172 xd->xprefix = rx.xprefix;
173 xd->name_len = rx.name_len;
174 xd->value_len = je16_to_cpu(rx.value_len);
175 xd->data_crc = je32_to_cpu(rx.data_crc);
176
177 spin_lock(&c->erase_completion_lock);
178 complete:
179 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
180 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
181 totlen = PAD(ref_totlen(c, jeb, raw));
182 if (ref_flags(raw) == REF_UNCHECKED) {
183 c->unchecked_size -= totlen; c->used_size += totlen;
184 jeb->unchecked_size -= totlen; jeb->used_size += totlen;
185 }
186 raw->flash_offset = ref_offset(raw) | ((xd->node==raw) ? REF_PRISTINE : REF_NORMAL);
187 }
188 spin_unlock(&c->erase_completion_lock);
189
190 /* unchecked xdatum is chained with c->xattr_unchecked */
191 list_del_init(&xd->xindex);
192
193 dbg_xattr("success on verfying xdatum (xid=%u, version=%u)\n",
194 xd->xid, xd->version);
195
196 return 0;
197 }
198
199 static int do_load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
200 {
201 /* must be called under down_write(xattr_sem) */
202 char *data;
203 size_t readlen;
204 uint32_t crc, length;
205 int i, ret, retry = 0;
206
207 BUG_ON(ref_flags(xd->node) != REF_PRISTINE);
208 BUG_ON(!list_empty(&xd->xindex));
209 retry:
210 length = xd->name_len + 1 + xd->value_len;
211 data = kmalloc(length, GFP_KERNEL);
212 if (!data)
213 return -ENOMEM;
214
215 ret = jffs2_flash_read(c, ref_offset(xd->node)+sizeof(struct jffs2_raw_xattr),
216 length, &readlen, data);
217
218 if (ret || length!=readlen) {
219 JFFS2_WARNING("jffs2_flash_read() returned %d, request=%d, readlen=%zu, at %#08x\n",
220 ret, length, readlen, ref_offset(xd->node));
221 kfree(data);
222 return ret ? ret : -EIO;
223 }
224
225 data[xd->name_len] = '\0';
226 crc = crc32(0, data, length);
227 if (crc != xd->data_crc) {
228 JFFS2_WARNING("node CRC failed (JFFS2_NODETYPE_XREF)"
229 " at %#08x, read: 0x%08x calculated: 0x%08x\n",
230 ref_offset(xd->node), xd->data_crc, crc);
231 kfree(data);
232 xd->flags |= JFFS2_XFLAGS_INVALID;
233 return -EIO;
234 }
235
236 xd->flags |= JFFS2_XFLAGS_HOT;
237 xd->xname = data;
238 xd->xvalue = data + xd->name_len+1;
239
240 c->xdatum_mem_usage += length;
241
242 xd->hashkey = xattr_datum_hashkey(xd->xprefix, xd->xname, xd->xvalue, xd->value_len);
243 i = xd->hashkey % XATTRINDEX_HASHSIZE;
244 list_add(&xd->xindex, &c->xattrindex[i]);
245 if (!retry) {
246 retry = 1;
247 reclaim_xattr_datum(c);
248 if (!xd->xname)
249 goto retry;
250 }
251
252 dbg_xattr("success on loading xdatum (xid=%u, xprefix=%u, xname='%s')\n",
253 xd->xid, xd->xprefix, xd->xname);
254
255 return 0;
256 }
257
258 static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
259 {
260 /* must be called under down_write(xattr_sem);
261 * rc < 0 : recoverable error, try again
262 * rc = 0 : success
263 * rc > 0 : Unrecoverable error, this node should be deleted.
264 */
265 int rc = 0;
266
267 BUG_ON(xd->flags & JFFS2_XFLAGS_DEAD);
268 if (xd->xname)
269 return 0;
270 if (xd->flags & JFFS2_XFLAGS_INVALID)
271 return -EIO;
272 if (unlikely(is_xattr_datum_unchecked(c, xd)))
273 rc = do_verify_xattr_datum(c, xd);
274 if (!rc)
275 rc = do_load_xattr_datum(c, xd);
276 return rc;
277 }
278
279 static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
280 {
281 /* must be called under down_write(xattr_sem) */
282 struct jffs2_raw_xattr rx;
283 struct kvec vecs[2];
284 size_t length;
285 int rc, totlen;
286 uint32_t phys_ofs = write_ofs(c);
287
288 BUG_ON(!xd->xname);
289 BUG_ON(xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID));
290
291 vecs[0].iov_base = &rx;
292 vecs[0].iov_len = sizeof(rx);
293 vecs[1].iov_base = xd->xname;
294 vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
295 totlen = vecs[0].iov_len + vecs[1].iov_len;
296
297 /* Setup raw-xattr */
298 memset(&rx, 0, sizeof(rx));
299 rx.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
300 rx.nodetype = cpu_to_je16(JFFS2_NODETYPE_XATTR);
301 rx.totlen = cpu_to_je32(PAD(totlen));
302 rx.hdr_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_unknown_node) - 4));
303
304 rx.xid = cpu_to_je32(xd->xid);
305 rx.version = cpu_to_je32(++xd->version);
306 rx.xprefix = xd->xprefix;
307 rx.name_len = xd->name_len;
308 rx.value_len = cpu_to_je16(xd->value_len);
309 rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
310 rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
311
312 rc = jffs2_flash_writev(c, vecs, 2, phys_ofs, &length, 0);
313 if (rc || totlen != length) {
314 JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%zu, at %#08x\n",
315 rc, totlen, length, phys_ofs);
316 rc = rc ? rc : -EIO;
317 if (length)
318 jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(totlen), NULL);
319
320 return rc;
321 }
322 /* success */
323 jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(totlen), (void *)xd);
324
325 dbg_xattr("success on saving xdatum (xid=%u, version=%u, xprefix=%u, xname='%s')\n",
326 xd->xid, xd->version, xd->xprefix, xd->xname);
327
328 return 0;
329 }
330
331 static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
332 int xprefix, const char *xname,
333 const char *xvalue, int xsize)
334 {
335 /* must be called under down_write(xattr_sem) */
336 struct jffs2_xattr_datum *xd;
337 uint32_t hashkey, name_len;
338 char *data;
339 int i, rc;
340
341 /* Search xattr_datum has same xname/xvalue by index */
342 hashkey = xattr_datum_hashkey(xprefix, xname, xvalue, xsize);
343 i = hashkey % XATTRINDEX_HASHSIZE;
344 list_for_each_entry(xd, &c->xattrindex[i], xindex) {
345 if (xd->hashkey==hashkey
346 && xd->xprefix==xprefix
347 && xd->value_len==xsize
348 && !strcmp(xd->xname, xname)
349 && !memcmp(xd->xvalue, xvalue, xsize)) {
350 atomic_inc(&xd->refcnt);
351 return xd;
352 }
353 }
354
355 /* Not found, Create NEW XATTR-Cache */
356 name_len = strlen(xname);
357
358 xd = jffs2_alloc_xattr_datum();
359 if (!xd)
360 return ERR_PTR(-ENOMEM);
361
362 data = kmalloc(name_len + 1 + xsize, GFP_KERNEL);
363 if (!data) {
364 jffs2_free_xattr_datum(xd);
365 return ERR_PTR(-ENOMEM);
366 }
367 strcpy(data, xname);
368 memcpy(data + name_len + 1, xvalue, xsize);
369
370 atomic_set(&xd->refcnt, 1);
371 xd->xid = ++c->highest_xid;
372 xd->flags |= JFFS2_XFLAGS_HOT;
373 xd->xprefix = xprefix;
374
375 xd->hashkey = hashkey;
376 xd->xname = data;
377 xd->xvalue = data + name_len + 1;
378 xd->name_len = name_len;
379 xd->value_len = xsize;
380 xd->data_crc = crc32(0, data, xd->name_len + 1 + xd->value_len);
381
382 rc = save_xattr_datum(c, xd);
383 if (rc) {
384 kfree(xd->xname);
385 jffs2_free_xattr_datum(xd);
386 return ERR_PTR(rc);
387 }
388
389 /* Insert Hash Index */
390 i = hashkey % XATTRINDEX_HASHSIZE;
391 list_add(&xd->xindex, &c->xattrindex[i]);
392
393 c->xdatum_mem_usage += (xd->name_len + 1 + xd->value_len);
394 reclaim_xattr_datum(c);
395
396 return xd;
397 }
398
399 static void unrefer_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
400 {
401 /* must be called under down_write(xattr_sem) */
402 if (atomic_dec_and_lock(&xd->refcnt, &c->erase_completion_lock)) {
403 unload_xattr_datum(c, xd);
404 xd->flags |= JFFS2_XFLAGS_DEAD;
405 if (xd->node == (void *)xd) {
406 BUG_ON(!(xd->flags & JFFS2_XFLAGS_INVALID));
407 jffs2_free_xattr_datum(xd);
408 } else {
409 list_add(&xd->xindex, &c->xattr_dead_list);
410 }
411 spin_unlock(&c->erase_completion_lock);
412
413 dbg_xattr("xdatum(xid=%u, version=%u) was removed.\n",
414 xd->xid, xd->version);
415 }
416 }
417
418 /* -------- xref related functions ------------------
419 * verify_xattr_ref(c, ref)
420 * is used to load xref information from medium. Because summary data does not
421 * contain xid/ino, it's necessary to verify once while mounting process.
422 * save_xattr_ref(c, ref)
423 * is used to write xref to medium. If delete marker is marked, it write
424 * a delete marker of xref into medium.
425 * create_xattr_ref(c, ic, xd)
426 * is used to create a new xref and write to medium.
427 * delete_xattr_ref(c, ref)
428 * is used to delete jffs2_xattr_ref. It marks xref XREF_DELETE_MARKER,
429 * and allows GC to reclaim those physical nodes.
430 * jffs2_xattr_delete_inode(c, ic)
431 * is called to remove xrefs related to obsolete inode when inode is unlinked.
432 * jffs2_xattr_free_inode(c, ic)
433 * is called to release xattr related objects when unmounting.
434 * check_xattr_ref_inode(c, ic)
435 * is used to confirm inode does not have duplicate xattr name/value pair.
436 * -------------------------------------------------- */
437 static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
438 {
439 struct jffs2_eraseblock *jeb;
440 struct jffs2_raw_node_ref *raw;
441 struct jffs2_raw_xref rr;
442 size_t readlen;
443 uint32_t crc, offset, totlen;
444 int rc;
445
446 spin_lock(&c->erase_completion_lock);
447 if (ref_flags(ref->node) != REF_UNCHECKED)
448 goto complete;
449 offset = ref_offset(ref->node);
450 spin_unlock(&c->erase_completion_lock);
451
452 rc = jffs2_flash_read(c, offset, sizeof(rr), &readlen, (char *)&rr);
453 if (rc || sizeof(rr) != readlen) {
454 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu, at %#08x\n",
455 rc, sizeof(rr), readlen, offset);
456 return rc ? rc : -EIO;
457 }
458 /* obsolete node */
459 crc = crc32(0, &rr, sizeof(rr) - 4);
460 if (crc != je32_to_cpu(rr.node_crc)) {
461 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
462 offset, je32_to_cpu(rr.node_crc), crc);
463 return -EIO;
464 }
465 if (je16_to_cpu(rr.magic) != JFFS2_MAGIC_BITMASK
466 || je16_to_cpu(rr.nodetype) != JFFS2_NODETYPE_XREF
467 || je32_to_cpu(rr.totlen) != PAD(sizeof(rr))) {
468 JFFS2_ERROR("inconsistent xref at %#08x, magic=%#04x/%#04x, "
469 "nodetype=%#04x/%#04x, totlen=%u/%zu\n",
470 offset, je16_to_cpu(rr.magic), JFFS2_MAGIC_BITMASK,
471 je16_to_cpu(rr.nodetype), JFFS2_NODETYPE_XREF,
472 je32_to_cpu(rr.totlen), PAD(sizeof(rr)));
473 return -EIO;
474 }
475 ref->ino = je32_to_cpu(rr.ino);
476 ref->xid = je32_to_cpu(rr.xid);
477 ref->xseqno = je32_to_cpu(rr.xseqno);
478 if (ref->xseqno > c->highest_xseqno)
479 c->highest_xseqno = (ref->xseqno & ~XREF_DELETE_MARKER);
480
481 spin_lock(&c->erase_completion_lock);
482 complete:
483 for (raw=ref->node; raw != (void *)ref; raw=raw->next_in_ino) {
484 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
485 totlen = PAD(ref_totlen(c, jeb, raw));
486 if (ref_flags(raw) == REF_UNCHECKED) {
487 c->unchecked_size -= totlen; c->used_size += totlen;
488 jeb->unchecked_size -= totlen; jeb->used_size += totlen;
489 }
490 raw->flash_offset = ref_offset(raw) | ((ref->node==raw) ? REF_PRISTINE : REF_NORMAL);
491 }
492 spin_unlock(&c->erase_completion_lock);
493
494 dbg_xattr("success on verifying xref (ino=%u, xid=%u) at %#08x\n",
495 ref->ino, ref->xid, ref_offset(ref->node));
496 return 0;
497 }
498
499 static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
500 {
501 /* must be called under down_write(xattr_sem) */
502 struct jffs2_raw_xref rr;
503 size_t length;
504 uint32_t xseqno, phys_ofs = write_ofs(c);
505 int ret;
506
507 rr.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
508 rr.nodetype = cpu_to_je16(JFFS2_NODETYPE_XREF);
509 rr.totlen = cpu_to_je32(PAD(sizeof(rr)));
510 rr.hdr_crc = cpu_to_je32(crc32(0, &rr, sizeof(struct jffs2_unknown_node) - 4));
511
512 xseqno = (c->highest_xseqno += 2);
513 if (is_xattr_ref_dead(ref)) {
514 xseqno |= XREF_DELETE_MARKER;
515 rr.ino = cpu_to_je32(ref->ino);
516 rr.xid = cpu_to_je32(ref->xid);
517 } else {
518 rr.ino = cpu_to_je32(ref->ic->ino);
519 rr.xid = cpu_to_je32(ref->xd->xid);
520 }
521 rr.xseqno = cpu_to_je32(xseqno);
522 rr.node_crc = cpu_to_je32(crc32(0, &rr, sizeof(rr) - 4));
523
524 ret = jffs2_flash_write(c, phys_ofs, sizeof(rr), &length, (char *)&rr);
525 if (ret || sizeof(rr) != length) {
526 JFFS2_WARNING("jffs2_flash_write() returned %d, request=%zu, retlen=%zu, at %#08x\n",
527 ret, sizeof(rr), length, phys_ofs);
528 ret = ret ? ret : -EIO;
529 if (length)
530 jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(sizeof(rr)), NULL);
531
532 return ret;
533 }
534 /* success */
535 ref->xseqno = xseqno;
536 jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), (void *)ref);
537
538 dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid);
539
540 return 0;
541 }
542
543 static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic,
544 struct jffs2_xattr_datum *xd)
545 {
546 /* must be called under down_write(xattr_sem) */
547 struct jffs2_xattr_ref *ref;
548 int ret;
549
550 ref = jffs2_alloc_xattr_ref();
551 if (!ref)
552 return ERR_PTR(-ENOMEM);
553 ref->ic = ic;
554 ref->xd = xd;
555
556 ret = save_xattr_ref(c, ref);
557 if (ret) {
558 jffs2_free_xattr_ref(ref);
559 return ERR_PTR(ret);
560 }
561
562 /* Chain to inode */
563 ref->next = ic->xref;
564 ic->xref = ref;
565
566 return ref; /* success */
567 }
568
569 static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
570 {
571 /* must be called under down_write(xattr_sem) */
572 struct jffs2_xattr_datum *xd;
573
574 xd = ref->xd;
575 ref->xseqno |= XREF_DELETE_MARKER;
576 ref->ino = ref->ic->ino;
577 ref->xid = ref->xd->xid;
578 spin_lock(&c->erase_completion_lock);
579 ref->next = c->xref_dead_list;
580 c->xref_dead_list = ref;
581 spin_unlock(&c->erase_completion_lock);
582
583 dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) was removed.\n",
584 ref->ino, ref->xid, ref->xseqno);
585
586 unrefer_xattr_datum(c, xd);
587 }
588
589 void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
590 {
591 /* It's called from jffs2_evict_inode() on inode removing.
592 When an inode with XATTR is removed, those XATTRs must be removed. */
593 struct jffs2_xattr_ref *ref, *_ref;
594
595 if (!ic || ic->pino_nlink > 0)
596 return;
597
598 down_write(&c->xattr_sem);
599 for (ref = ic->xref; ref; ref = _ref) {
600 _ref = ref->next;
601 delete_xattr_ref(c, ref);
602 }
603 ic->xref = NULL;
604 up_write(&c->xattr_sem);
605 }
606
607 void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
608 {
609 /* It's called from jffs2_free_ino_caches() until unmounting FS. */
610 struct jffs2_xattr_datum *xd;
611 struct jffs2_xattr_ref *ref, *_ref;
612
613 down_write(&c->xattr_sem);
614 for (ref = ic->xref; ref; ref = _ref) {
615 _ref = ref->next;
616 xd = ref->xd;
617 if (atomic_dec_and_test(&xd->refcnt)) {
618 unload_xattr_datum(c, xd);
619 jffs2_free_xattr_datum(xd);
620 }
621 jffs2_free_xattr_ref(ref);
622 }
623 ic->xref = NULL;
624 up_write(&c->xattr_sem);
625 }
626
627 static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
628 {
629 /* success of check_xattr_ref_inode() means that inode (ic) dose not have
630 * duplicate name/value pairs. If duplicate name/value pair would be found,
631 * one will be removed.
632 */
633 struct jffs2_xattr_ref *ref, *cmp, **pref, **pcmp;
634 int rc = 0;
635
636 if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
637 return 0;
638 down_write(&c->xattr_sem);
639 retry:
640 rc = 0;
641 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
642 if (!ref->xd->xname) {
643 rc = load_xattr_datum(c, ref->xd);
644 if (unlikely(rc > 0)) {
645 *pref = ref->next;
646 delete_xattr_ref(c, ref);
647 goto retry;
648 } else if (unlikely(rc < 0))
649 goto out;
650 }
651 for (cmp=ref->next, pcmp=&ref->next; cmp; pcmp=&cmp->next, cmp=cmp->next) {
652 if (!cmp->xd->xname) {
653 ref->xd->flags |= JFFS2_XFLAGS_BIND;
654 rc = load_xattr_datum(c, cmp->xd);
655 ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
656 if (unlikely(rc > 0)) {
657 *pcmp = cmp->next;
658 delete_xattr_ref(c, cmp);
659 goto retry;
660 } else if (unlikely(rc < 0))
661 goto out;
662 }
663 if (ref->xd->xprefix == cmp->xd->xprefix
664 && !strcmp(ref->xd->xname, cmp->xd->xname)) {
665 if (ref->xseqno > cmp->xseqno) {
666 *pcmp = cmp->next;
667 delete_xattr_ref(c, cmp);
668 } else {
669 *pref = ref->next;
670 delete_xattr_ref(c, ref);
671 }
672 goto retry;
673 }
674 }
675 }
676 ic->flags |= INO_FLAGS_XATTR_CHECKED;
677 out:
678 up_write(&c->xattr_sem);
679
680 return rc;
681 }
682
683 /* -------- xattr subsystem functions ---------------
684 * jffs2_init_xattr_subsystem(c)
685 * is used to initialize semaphore and list_head, and some variables.
686 * jffs2_find_xattr_datum(c, xid)
687 * is used to lookup xdatum while scanning process.
688 * jffs2_clear_xattr_subsystem(c)
689 * is used to release any xattr related objects.
690 * jffs2_build_xattr_subsystem(c)
691 * is used to associate xdatum and xref while super block building process.
692 * jffs2_setup_xattr_datum(c, xid, version)
693 * is used to insert xdatum while scanning process.
694 * -------------------------------------------------- */
695 void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
696 {
697 int i;
698
699 for (i=0; i < XATTRINDEX_HASHSIZE; i++)
700 INIT_LIST_HEAD(&c->xattrindex[i]);
701 INIT_LIST_HEAD(&c->xattr_unchecked);
702 INIT_LIST_HEAD(&c->xattr_dead_list);
703 c->xref_dead_list = NULL;
704 c->xref_temp = NULL;
705
706 init_rwsem(&c->xattr_sem);
707 c->highest_xid = 0;
708 c->highest_xseqno = 0;
709 c->xdatum_mem_usage = 0;
710 c->xdatum_mem_threshold = 32 * 1024; /* Default 32KB */
711 }
712
713 static struct jffs2_xattr_datum *jffs2_find_xattr_datum(struct jffs2_sb_info *c, uint32_t xid)
714 {
715 struct jffs2_xattr_datum *xd;
716 int i = xid % XATTRINDEX_HASHSIZE;
717
718 /* It's only used in scanning/building process. */
719 BUG_ON(!(c->flags & (JFFS2_SB_FLAG_SCANNING|JFFS2_SB_FLAG_BUILDING)));
720
721 list_for_each_entry(xd, &c->xattrindex[i], xindex) {
722 if (xd->xid==xid)
723 return xd;
724 }
725 return NULL;
726 }
727
728 void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
729 {
730 struct jffs2_xattr_datum *xd, *_xd;
731 struct jffs2_xattr_ref *ref, *_ref;
732 int i;
733
734 for (ref=c->xref_temp; ref; ref = _ref) {
735 _ref = ref->next;
736 jffs2_free_xattr_ref(ref);
737 }
738
739 for (ref=c->xref_dead_list; ref; ref = _ref) {
740 _ref = ref->next;
741 jffs2_free_xattr_ref(ref);
742 }
743
744 for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
745 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
746 list_del(&xd->xindex);
747 if (xd->xname)
748 kfree(xd->xname);
749 jffs2_free_xattr_datum(xd);
750 }
751 }
752
753 list_for_each_entry_safe(xd, _xd, &c->xattr_dead_list, xindex) {
754 list_del(&xd->xindex);
755 jffs2_free_xattr_datum(xd);
756 }
757 list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
758 list_del(&xd->xindex);
759 jffs2_free_xattr_datum(xd);
760 }
761 }
762
763 #define XREF_TMPHASH_SIZE (128)
764 void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
765 {
766 struct jffs2_xattr_ref *ref, *_ref;
767 struct jffs2_xattr_ref *xref_tmphash[XREF_TMPHASH_SIZE];
768 struct jffs2_xattr_datum *xd, *_xd;
769 struct jffs2_inode_cache *ic;
770 struct jffs2_raw_node_ref *raw;
771 int i, xdatum_count = 0, xdatum_unchecked_count = 0, xref_count = 0;
772 int xdatum_orphan_count = 0, xref_orphan_count = 0, xref_dead_count = 0;
773
774 BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
775
776 /* Phase.1 : Merge same xref */
777 for (i=0; i < XREF_TMPHASH_SIZE; i++)
778 xref_tmphash[i] = NULL;
779 for (ref=c->xref_temp; ref; ref=_ref) {
780 struct jffs2_xattr_ref *tmp;
781
782 _ref = ref->next;
783 if (ref_flags(ref->node) != REF_PRISTINE) {
784 if (verify_xattr_ref(c, ref)) {
785 BUG_ON(ref->node->next_in_ino != (void *)ref);
786 ref->node->next_in_ino = NULL;
787 jffs2_mark_node_obsolete(c, ref->node);
788 jffs2_free_xattr_ref(ref);
789 continue;
790 }
791 }
792
793 i = (ref->ino ^ ref->xid) % XREF_TMPHASH_SIZE;
794 for (tmp=xref_tmphash[i]; tmp; tmp=tmp->next) {
795 if (tmp->ino == ref->ino && tmp->xid == ref->xid)
796 break;
797 }
798 if (tmp) {
799 raw = ref->node;
800 if (ref->xseqno > tmp->xseqno) {
801 tmp->xseqno = ref->xseqno;
802 raw->next_in_ino = tmp->node;
803 tmp->node = raw;
804 } else {
805 raw->next_in_ino = tmp->node->next_in_ino;
806 tmp->node->next_in_ino = raw;
807 }
808 jffs2_free_xattr_ref(ref);
809 continue;
810 } else {
811 ref->next = xref_tmphash[i];
812 xref_tmphash[i] = ref;
813 }
814 }
815 c->xref_temp = NULL;
816
817 /* Phase.2 : Bind xref with inode_cache and xattr_datum */
818 for (i=0; i < XREF_TMPHASH_SIZE; i++) {
819 for (ref=xref_tmphash[i]; ref; ref=_ref) {
820 xref_count++;
821 _ref = ref->next;
822 if (is_xattr_ref_dead(ref)) {
823 ref->next = c->xref_dead_list;
824 c->xref_dead_list = ref;
825 xref_dead_count++;
826 continue;
827 }
828 /* At this point, ref->xid and ref->ino contain XID and inode number.
829 ref->xd and ref->ic are not valid yet. */
830 xd = jffs2_find_xattr_datum(c, ref->xid);
831 ic = jffs2_get_ino_cache(c, ref->ino);
832 if (!xd || !ic || !ic->pino_nlink) {
833 dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) is orphan.\n",
834 ref->ino, ref->xid, ref->xseqno);
835 ref->xseqno |= XREF_DELETE_MARKER;
836 ref->next = c->xref_dead_list;
837 c->xref_dead_list = ref;
838 xref_orphan_count++;
839 continue;
840 }
841 ref->xd = xd;
842 ref->ic = ic;
843 atomic_inc(&xd->refcnt);
844 ref->next = ic->xref;
845 ic->xref = ref;
846 }
847 }
848
849 /* Phase.3 : Link unchecked xdatum to xattr_unchecked list */
850 for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
851 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
852 xdatum_count++;
853 list_del_init(&xd->xindex);
854 if (!atomic_read(&xd->refcnt)) {
855 dbg_xattr("xdatum(xid=%u, version=%u) is orphan.\n",
856 xd->xid, xd->version);
857 xd->flags |= JFFS2_XFLAGS_DEAD;
858 list_add(&xd->xindex, &c->xattr_unchecked);
859 xdatum_orphan_count++;
860 continue;
861 }
862 if (is_xattr_datum_unchecked(c, xd)) {
863 dbg_xattr("unchecked xdatum(xid=%u, version=%u)\n",
864 xd->xid, xd->version);
865 list_add(&xd->xindex, &c->xattr_unchecked);
866 xdatum_unchecked_count++;
867 }
868 }
869 }
870 /* build complete */
871 JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum"
872 " (%u unchecked, %u orphan) and "
873 "%u of xref (%u dead, %u orphan) found.\n",
874 xdatum_count, xdatum_unchecked_count, xdatum_orphan_count,
875 xref_count, xref_dead_count, xref_orphan_count);
876 }
877
878 struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
879 uint32_t xid, uint32_t version)
880 {
881 struct jffs2_xattr_datum *xd;
882
883 xd = jffs2_find_xattr_datum(c, xid);
884 if (!xd) {
885 xd = jffs2_alloc_xattr_datum();
886 if (!xd)
887 return ERR_PTR(-ENOMEM);
888 xd->xid = xid;
889 xd->version = version;
890 if (xd->xid > c->highest_xid)
891 c->highest_xid = xd->xid;
892 list_add_tail(&xd->xindex, &c->xattrindex[xid % XATTRINDEX_HASHSIZE]);
893 }
894 return xd;
895 }
896
897 /* -------- xattr subsystem functions ---------------
898 * xprefix_to_handler(xprefix)
899 * is used to translate xprefix into xattr_handler.
900 * jffs2_listxattr(dentry, buffer, size)
901 * is an implementation of listxattr handler on jffs2.
902 * do_jffs2_getxattr(inode, xprefix, xname, buffer, size)
903 * is an implementation of getxattr handler on jffs2.
904 * do_jffs2_setxattr(inode, xprefix, xname, buffer, size, flags)
905 * is an implementation of setxattr handler on jffs2.
906 * -------------------------------------------------- */
907 const struct xattr_handler *jffs2_xattr_handlers[] = {
908 &jffs2_user_xattr_handler,
909 #ifdef CONFIG_JFFS2_FS_SECURITY
910 &jffs2_security_xattr_handler,
911 #endif
912 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
913 &jffs2_acl_access_xattr_handler,
914 &jffs2_acl_default_xattr_handler,
915 #endif
916 &jffs2_trusted_xattr_handler,
917 NULL
918 };
919
920 static const struct xattr_handler *xprefix_to_handler(int xprefix) {
921 const struct xattr_handler *ret;
922
923 switch (xprefix) {
924 case JFFS2_XPREFIX_USER:
925 ret = &jffs2_user_xattr_handler;
926 break;
927 #ifdef CONFIG_JFFS2_FS_SECURITY
928 case JFFS2_XPREFIX_SECURITY:
929 ret = &jffs2_security_xattr_handler;
930 break;
931 #endif
932 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
933 case JFFS2_XPREFIX_ACL_ACCESS:
934 ret = &jffs2_acl_access_xattr_handler;
935 break;
936 case JFFS2_XPREFIX_ACL_DEFAULT:
937 ret = &jffs2_acl_default_xattr_handler;
938 break;
939 #endif
940 case JFFS2_XPREFIX_TRUSTED:
941 ret = &jffs2_trusted_xattr_handler;
942 break;
943 default:
944 ret = NULL;
945 break;
946 }
947 return ret;
948 }
949
950 ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
951 {
952 struct inode *inode = dentry->d_inode;
953 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
954 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
955 struct jffs2_inode_cache *ic = f->inocache;
956 struct jffs2_xattr_ref *ref, **pref;
957 struct jffs2_xattr_datum *xd;
958 const struct xattr_handler *xhandle;
959 ssize_t len, rc;
960 int retry = 0;
961
962 rc = check_xattr_ref_inode(c, ic);
963 if (unlikely(rc))
964 return rc;
965
966 down_read(&c->xattr_sem);
967 retry:
968 len = 0;
969 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
970 BUG_ON(ref->ic != ic);
971 xd = ref->xd;
972 if (!xd->xname) {
973 /* xdatum is unchached */
974 if (!retry) {
975 retry = 1;
976 up_read(&c->xattr_sem);
977 down_write(&c->xattr_sem);
978 goto retry;
979 } else {
980 rc = load_xattr_datum(c, xd);
981 if (unlikely(rc > 0)) {
982 *pref = ref->next;
983 delete_xattr_ref(c, ref);
984 goto retry;
985 } else if (unlikely(rc < 0))
986 goto out;
987 }
988 }
989 xhandle = xprefix_to_handler(xd->xprefix);
990 if (!xhandle)
991 continue;
992 if (buffer) {
993 rc = xhandle->list(dentry, buffer+len, size-len,
994 xd->xname, xd->name_len, xd->flags);
995 } else {
996 rc = xhandle->list(dentry, NULL, 0, xd->xname,
997 xd->name_len, xd->flags);
998 }
999 if (rc < 0)
1000 goto out;
1001 len += rc;
1002 }
1003 rc = len;
1004 out:
1005 if (!retry) {
1006 up_read(&c->xattr_sem);
1007 } else {
1008 up_write(&c->xattr_sem);
1009 }
1010 return rc;
1011 }
1012
1013 int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
1014 char *buffer, size_t size)
1015 {
1016 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1017 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1018 struct jffs2_inode_cache *ic = f->inocache;
1019 struct jffs2_xattr_datum *xd;
1020 struct jffs2_xattr_ref *ref, **pref;
1021 int rc, retry = 0;
1022
1023 rc = check_xattr_ref_inode(c, ic);
1024 if (unlikely(rc))
1025 return rc;
1026
1027 down_read(&c->xattr_sem);
1028 retry:
1029 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1030 BUG_ON(ref->ic!=ic);
1031
1032 xd = ref->xd;
1033 if (xd->xprefix != xprefix)
1034 continue;
1035 if (!xd->xname) {
1036 /* xdatum is unchached */
1037 if (!retry) {
1038 retry = 1;
1039 up_read(&c->xattr_sem);
1040 down_write(&c->xattr_sem);
1041 goto retry;
1042 } else {
1043 rc = load_xattr_datum(c, xd);
1044 if (unlikely(rc > 0)) {
1045 *pref = ref->next;
1046 delete_xattr_ref(c, ref);
1047 goto retry;
1048 } else if (unlikely(rc < 0)) {
1049 goto out;
1050 }
1051 }
1052 }
1053 if (!strcmp(xname, xd->xname)) {
1054 rc = xd->value_len;
1055 if (buffer) {
1056 if (size < rc) {
1057 rc = -ERANGE;
1058 } else {
1059 memcpy(buffer, xd->xvalue, rc);
1060 }
1061 }
1062 goto out;
1063 }
1064 }
1065 rc = -ENODATA;
1066 out:
1067 if (!retry) {
1068 up_read(&c->xattr_sem);
1069 } else {
1070 up_write(&c->xattr_sem);
1071 }
1072 return rc;
1073 }
1074
1075 int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
1076 const char *buffer, size_t size, int flags)
1077 {
1078 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1079 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1080 struct jffs2_inode_cache *ic = f->inocache;
1081 struct jffs2_xattr_datum *xd;
1082 struct jffs2_xattr_ref *ref, *newref, **pref;
1083 uint32_t length, request;
1084 int rc;
1085
1086 rc = check_xattr_ref_inode(c, ic);
1087 if (unlikely(rc))
1088 return rc;
1089
1090 request = PAD(sizeof(struct jffs2_raw_xattr) + strlen(xname) + 1 + size);
1091 rc = jffs2_reserve_space(c, request, &length,
1092 ALLOC_NORMAL, JFFS2_SUMMARY_XATTR_SIZE);
1093 if (rc) {
1094 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1095 return rc;
1096 }
1097
1098 /* Find existing xattr */
1099 down_write(&c->xattr_sem);
1100 retry:
1101 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1102 xd = ref->xd;
1103 if (xd->xprefix != xprefix)
1104 continue;
1105 if (!xd->xname) {
1106 rc = load_xattr_datum(c, xd);
1107 if (unlikely(rc > 0)) {
1108 *pref = ref->next;
1109 delete_xattr_ref(c, ref);
1110 goto retry;
1111 } else if (unlikely(rc < 0))
1112 goto out;
1113 }
1114 if (!strcmp(xd->xname, xname)) {
1115 if (flags & XATTR_CREATE) {
1116 rc = -EEXIST;
1117 goto out;
1118 }
1119 if (!buffer) {
1120 ref->ino = ic->ino;
1121 ref->xid = xd->xid;
1122 ref->xseqno |= XREF_DELETE_MARKER;
1123 rc = save_xattr_ref(c, ref);
1124 if (!rc) {
1125 *pref = ref->next;
1126 spin_lock(&c->erase_completion_lock);
1127 ref->next = c->xref_dead_list;
1128 c->xref_dead_list = ref;
1129 spin_unlock(&c->erase_completion_lock);
1130 unrefer_xattr_datum(c, xd);
1131 } else {
1132 ref->ic = ic;
1133 ref->xd = xd;
1134 ref->xseqno &= ~XREF_DELETE_MARKER;
1135 }
1136 goto out;
1137 }
1138 goto found;
1139 }
1140 }
1141 /* not found */
1142 if (flags & XATTR_REPLACE) {
1143 rc = -ENODATA;
1144 goto out;
1145 }
1146 if (!buffer) {
1147 rc = -ENODATA;
1148 goto out;
1149 }
1150 found:
1151 xd = create_xattr_datum(c, xprefix, xname, buffer, size);
1152 if (IS_ERR(xd)) {
1153 rc = PTR_ERR(xd);
1154 goto out;
1155 }
1156 up_write(&c->xattr_sem);
1157 jffs2_complete_reservation(c);
1158
1159 /* create xattr_ref */
1160 request = PAD(sizeof(struct jffs2_raw_xref));
1161 rc = jffs2_reserve_space(c, request, &length,
1162 ALLOC_NORMAL, JFFS2_SUMMARY_XREF_SIZE);
1163 down_write(&c->xattr_sem);
1164 if (rc) {
1165 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1166 unrefer_xattr_datum(c, xd);
1167 up_write(&c->xattr_sem);
1168 return rc;
1169 }
1170 if (ref)
1171 *pref = ref->next;
1172 newref = create_xattr_ref(c, ic, xd);
1173 if (IS_ERR(newref)) {
1174 if (ref) {
1175 ref->next = ic->xref;
1176 ic->xref = ref;
1177 }
1178 rc = PTR_ERR(newref);
1179 unrefer_xattr_datum(c, xd);
1180 } else if (ref) {
1181 delete_xattr_ref(c, ref);
1182 }
1183 out:
1184 up_write(&c->xattr_sem);
1185 jffs2_complete_reservation(c);
1186 return rc;
1187 }
1188
1189 /* -------- garbage collector functions -------------
1190 * jffs2_garbage_collect_xattr_datum(c, xd, raw)
1191 * is used to move xdatum into new node.
1192 * jffs2_garbage_collect_xattr_ref(c, ref, raw)
1193 * is used to move xref into new node.
1194 * jffs2_verify_xattr(c)
1195 * is used to call do_verify_xattr_datum() before garbage collecting.
1196 * jffs2_release_xattr_datum(c, xd)
1197 * is used to release an in-memory object of xdatum.
1198 * jffs2_release_xattr_ref(c, ref)
1199 * is used to release an in-memory object of xref.
1200 * -------------------------------------------------- */
1201 int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
1202 struct jffs2_raw_node_ref *raw)
1203 {
1204 uint32_t totlen, length, old_ofs;
1205 int rc = 0;
1206
1207 down_write(&c->xattr_sem);
1208 if (xd->node != raw)
1209 goto out;
1210 if (xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID))
1211 goto out;
1212
1213 rc = load_xattr_datum(c, xd);
1214 if (unlikely(rc)) {
1215 rc = (rc > 0) ? 0 : rc;
1216 goto out;
1217 }
1218 old_ofs = ref_offset(xd->node);
1219 totlen = PAD(sizeof(struct jffs2_raw_xattr)
1220 + xd->name_len + 1 + xd->value_len);
1221 rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XATTR_SIZE);
1222 if (rc) {
1223 JFFS2_WARNING("jffs2_reserve_space_gc()=%d, request=%u\n", rc, totlen);
1224 goto out;
1225 }
1226 rc = save_xattr_datum(c, xd);
1227 if (!rc)
1228 dbg_xattr("xdatum (xid=%u, version=%u) GC'ed from %#08x to %08x\n",
1229 xd->xid, xd->version, old_ofs, ref_offset(xd->node));
1230 out:
1231 if (!rc)
1232 jffs2_mark_node_obsolete(c, raw);
1233 up_write(&c->xattr_sem);
1234 return rc;
1235 }
1236
1237 int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
1238 struct jffs2_raw_node_ref *raw)
1239 {
1240 uint32_t totlen, length, old_ofs;
1241 int rc = 0;
1242
1243 down_write(&c->xattr_sem);
1244 BUG_ON(!ref->node);
1245
1246 if (ref->node != raw)
1247 goto out;
1248 if (is_xattr_ref_dead(ref) && (raw->next_in_ino == (void *)ref))
1249 goto out;
1250
1251 old_ofs = ref_offset(ref->node);
1252 totlen = ref_totlen(c, c->gcblock, ref->node);
1253
1254 rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XREF_SIZE);
1255 if (rc) {
1256 JFFS2_WARNING("%s: jffs2_reserve_space_gc() = %d, request = %u\n",
1257 __func__, rc, totlen);
1258 rc = rc ? rc : -EBADFD;
1259 goto out;
1260 }
1261 rc = save_xattr_ref(c, ref);
1262 if (!rc)
1263 dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n",
1264 ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node));
1265 out:
1266 if (!rc)
1267 jffs2_mark_node_obsolete(c, raw);
1268 up_write(&c->xattr_sem);
1269 return rc;
1270 }
1271
1272 int jffs2_verify_xattr(struct jffs2_sb_info *c)
1273 {
1274 struct jffs2_xattr_datum *xd, *_xd;
1275 struct jffs2_eraseblock *jeb;
1276 struct jffs2_raw_node_ref *raw;
1277 uint32_t totlen;
1278 int rc;
1279
1280 down_write(&c->xattr_sem);
1281 list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
1282 rc = do_verify_xattr_datum(c, xd);
1283 if (rc < 0)
1284 continue;
1285 list_del_init(&xd->xindex);
1286 spin_lock(&c->erase_completion_lock);
1287 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
1288 if (ref_flags(raw) != REF_UNCHECKED)
1289 continue;
1290 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
1291 totlen = PAD(ref_totlen(c, jeb, raw));
1292 c->unchecked_size -= totlen; c->used_size += totlen;
1293 jeb->unchecked_size -= totlen; jeb->used_size += totlen;
1294 raw->flash_offset = ref_offset(raw)
1295 | ((xd->node == (void *)raw) ? REF_PRISTINE : REF_NORMAL);
1296 }
1297 if (xd->flags & JFFS2_XFLAGS_DEAD)
1298 list_add(&xd->xindex, &c->xattr_dead_list);
1299 spin_unlock(&c->erase_completion_lock);
1300 }
1301 up_write(&c->xattr_sem);
1302 return list_empty(&c->xattr_unchecked) ? 1 : 0;
1303 }
1304
1305 void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
1306 {
1307 /* must be called under spin_lock(&c->erase_completion_lock) */
1308 if (atomic_read(&xd->refcnt) || xd->node != (void *)xd)
1309 return;
1310
1311 list_del(&xd->xindex);
1312 jffs2_free_xattr_datum(xd);
1313 }
1314
1315 void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
1316 {
1317 /* must be called under spin_lock(&c->erase_completion_lock) */
1318 struct jffs2_xattr_ref *tmp, **ptmp;
1319
1320 if (ref->node != (void *)ref)
1321 return;
1322
1323 for (tmp=c->xref_dead_list, ptmp=&c->xref_dead_list; tmp; ptmp=&tmp->next, tmp=tmp->next) {
1324 if (ref == tmp) {
1325 *ptmp = tmp->next;
1326 break;
1327 }
1328 }
1329 jffs2_free_xattr_ref(ref);
1330 }
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