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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#define JFFS2_XATTR_IS_CORRUPTED 1
15
16#include <linux/kernel.h>
17#include <linux/slab.h>
18#include <linux/fs.h>
19#include <linux/time.h>
20#include <linux/pagemap.h>
21#include <linux/highmem.h>
22#include <linux/crc32.h>
23#include <linux/jffs2.h>
24#include <linux/xattr.h>
25#include <linux/posix_acl_xattr.h>
26#include <linux/mtd/mtd.h>
27#include "nodelist.h"
28/* -------- xdatum related functions ----------------
29 * xattr_datum_hashkey(xprefix, xname, xvalue, xsize)
30 * is used to calcurate xdatum hashkey. The reminder of hashkey into XATTRINDEX_HASHSIZE is
31 * the index of the xattr name/value pair cache (c->xattrindex).
32 * is_xattr_datum_unchecked(c, xd)
33 * returns 1, if xdatum contains any unchecked raw nodes. if all raw nodes are not
34 * unchecked, it returns 0.
35 * unload_xattr_datum(c, xd)
36 * is used to release xattr name/value pair and detach from c->xattrindex.
37 * reclaim_xattr_datum(c)
38 * is used to reclaim xattr name/value pairs on the xattr name/value pair cache when
39 * memory usage by cache is over c->xdatum_mem_threshold. Currently, this threshold
40 * is hard coded as 32KiB.
41 * do_verify_xattr_datum(c, xd)
42 * is used to load the xdatum informations without name/value pair from the medium.
43 * It's necessary once, because those informations are not collected during mounting
44 * process when EBS is enabled.
45 * 0 will be returned, if success. An negative return value means recoverable error, and
46 * positive return value means unrecoverable error. Thus, caller must remove this xdatum
47 * and xref when it returned positive value.
48 * do_load_xattr_datum(c, xd)
49 * is used to load name/value pair from the medium.
50 * The meanings of return value is same as do_verify_xattr_datum().
51 * load_xattr_datum(c, xd)
52 * is used to be as a wrapper of do_verify_xattr_datum() and do_load_xattr_datum().
53 * If xd need to call do_verify_xattr_datum() at first, it's called before calling
54 * do_load_xattr_datum(). The meanings of return value is same as do_verify_xattr_datum().
55 * save_xattr_datum(c, xd)
56 * is used to write xdatum to medium. xd->version will be incremented.
57 * create_xattr_datum(c, xprefix, xname, xvalue, xsize)
58 * is used to create new xdatum and write to medium.
59 * unrefer_xattr_datum(c, xd)
60 * is used to delete a xdatum. When nobody refers this xdatum, JFFS2_XFLAGS_DEAD
61 * is set on xd->flags and chained xattr_dead_list or release it immediately.
62 * In the first case, the garbage collector release it later.
63 * -------------------------------------------------- */
64static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
65{
66 int name_len = strlen(xname);
67
68 return crc32(xprefix, xname, name_len) ^ crc32(xprefix, xvalue, xsize);
69}
70
71static int is_xattr_datum_unchecked(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
72{
73 struct jffs2_raw_node_ref *raw;
74 int rc = 0;
75
76 spin_lock(lock: &c->erase_completion_lock);
77 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
78 if (ref_flags(raw) == REF_UNCHECKED) {
79 rc = 1;
80 break;
81 }
82 }
83 spin_unlock(lock: &c->erase_completion_lock);
84 return rc;
85}
86
87static void unload_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
88{
89 /* must be called under down_write(xattr_sem) */
90 D1(dbg_xattr("%s: xid=%u, version=%u\n", __func__, xd->xid, xd->version));
91 if (xd->xname) {
92 c->xdatum_mem_usage -= (xd->name_len + 1 + xd->value_len);
93 kfree(objp: xd->xname);
94 }
95
96 list_del_init(entry: &xd->xindex);
97 xd->hashkey = 0;
98 xd->xname = NULL;
99 xd->xvalue = NULL;
100}
101
102static void reclaim_xattr_datum(struct jffs2_sb_info *c)
103{
104 /* must be called under down_write(xattr_sem) */
105 struct jffs2_xattr_datum *xd, *_xd;
106 uint32_t target, before;
107 static int index = 0;
108 int count;
109
110 if (c->xdatum_mem_threshold > c->xdatum_mem_usage)
111 return;
112
113 before = c->xdatum_mem_usage;
114 target = c->xdatum_mem_usage * 4 / 5; /* 20% reduction */
115 for (count = 0; count < XATTRINDEX_HASHSIZE; count++) {
116 list_for_each_entry_safe(xd, _xd, &c->xattrindex[index], xindex) {
117 if (xd->flags & JFFS2_XFLAGS_HOT) {
118 xd->flags &= ~JFFS2_XFLAGS_HOT;
119 } else if (!(xd->flags & JFFS2_XFLAGS_BIND)) {
120 unload_xattr_datum(c, xd);
121 }
122 if (c->xdatum_mem_usage <= target)
123 goto out;
124 }
125 index = (index+1) % XATTRINDEX_HASHSIZE;
126 }
127 out:
128 JFFS2_NOTICE("xdatum_mem_usage from %u byte to %u byte (%u byte reclaimed)\n",
129 before, c->xdatum_mem_usage, before - c->xdatum_mem_usage);
130}
131
132static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
133{
134 /* must be called under down_write(xattr_sem) */
135 struct jffs2_eraseblock *jeb;
136 struct jffs2_raw_node_ref *raw;
137 struct jffs2_raw_xattr rx;
138 size_t readlen;
139 uint32_t crc, offset, totlen;
140 int rc;
141
142 spin_lock(lock: &c->erase_completion_lock);
143 offset = ref_offset(xd->node);
144 if (ref_flags(xd->node) == REF_PRISTINE)
145 goto complete;
146 spin_unlock(lock: &c->erase_completion_lock);
147
148 rc = jffs2_flash_read(c, ofs: offset, len: sizeof(rx), retlen: &readlen, buf: (char *)&rx);
149 if (rc || readlen != sizeof(rx)) {
150 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
151 rc, sizeof(rx), readlen, offset);
152 return rc ? rc : -EIO;
153 }
154 crc = crc32(0, &rx, sizeof(rx) - 4);
155 if (crc != je32_to_cpu(rx.node_crc)) {
156 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
157 offset, je32_to_cpu(rx.hdr_crc), crc);
158 xd->flags |= JFFS2_XFLAGS_INVALID;
159 return JFFS2_XATTR_IS_CORRUPTED;
160 }
161 totlen = PAD(sizeof(rx) + rx.name_len + 1 + je16_to_cpu(rx.value_len));
162 if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
163 || je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
164 || je32_to_cpu(rx.totlen) != totlen
165 || je32_to_cpu(rx.xid) != xd->xid
166 || je32_to_cpu(rx.version) != xd->version) {
167 JFFS2_ERROR("inconsistent xdatum at %#08x, magic=%#04x/%#04x, "
168 "nodetype=%#04x/%#04x, totlen=%u/%u, xid=%u/%u, version=%u/%u\n",
169 offset, je16_to_cpu(rx.magic), JFFS2_MAGIC_BITMASK,
170 je16_to_cpu(rx.nodetype), JFFS2_NODETYPE_XATTR,
171 je32_to_cpu(rx.totlen), totlen,
172 je32_to_cpu(rx.xid), xd->xid,
173 je32_to_cpu(rx.version), xd->version);
174 xd->flags |= JFFS2_XFLAGS_INVALID;
175 return JFFS2_XATTR_IS_CORRUPTED;
176 }
177 xd->xprefix = rx.xprefix;
178 xd->name_len = rx.name_len;
179 xd->value_len = je16_to_cpu(rx.value_len);
180 xd->data_crc = je32_to_cpu(rx.data_crc);
181
182 spin_lock(lock: &c->erase_completion_lock);
183 complete:
184 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
185 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
186 totlen = PAD(ref_totlen(c, jeb, raw));
187 if (ref_flags(raw) == REF_UNCHECKED) {
188 c->unchecked_size -= totlen; c->used_size += totlen;
189 jeb->unchecked_size -= totlen; jeb->used_size += totlen;
190 }
191 raw->flash_offset = ref_offset(raw) | ((xd->node==raw) ? REF_PRISTINE : REF_NORMAL);
192 }
193 spin_unlock(lock: &c->erase_completion_lock);
194
195 /* unchecked xdatum is chained with c->xattr_unchecked */
196 list_del_init(entry: &xd->xindex);
197
198 dbg_xattr("success on verifying xdatum (xid=%u, version=%u)\n",
199 xd->xid, xd->version);
200
201 return 0;
202}
203
204static int do_load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
205{
206 /* must be called under down_write(xattr_sem) */
207 char *data;
208 size_t readlen;
209 uint32_t crc, length;
210 int i, ret, retry = 0;
211
212 BUG_ON(ref_flags(xd->node) != REF_PRISTINE);
213 BUG_ON(!list_empty(&xd->xindex));
214 retry:
215 length = xd->name_len + 1 + xd->value_len;
216 data = kmalloc(size: length, GFP_KERNEL);
217 if (!data)
218 return -ENOMEM;
219
220 ret = jffs2_flash_read(c, ref_offset(xd->node)+sizeof(struct jffs2_raw_xattr),
221 len: length, retlen: &readlen, buf: data);
222
223 if (ret || length!=readlen) {
224 JFFS2_WARNING("jffs2_flash_read() returned %d, request=%d, readlen=%zu, at %#08x\n",
225 ret, length, readlen, ref_offset(xd->node));
226 kfree(objp: data);
227 return ret ? ret : -EIO;
228 }
229
230 data[xd->name_len] = '\0';
231 crc = crc32(0, data, length);
232 if (crc != xd->data_crc) {
233 JFFS2_WARNING("node CRC failed (JFFS2_NODETYPE_XATTR)"
234 " at %#08x, read: 0x%08x calculated: 0x%08x\n",
235 ref_offset(xd->node), xd->data_crc, crc);
236 kfree(objp: data);
237 xd->flags |= JFFS2_XFLAGS_INVALID;
238 return JFFS2_XATTR_IS_CORRUPTED;
239 }
240
241 xd->flags |= JFFS2_XFLAGS_HOT;
242 xd->xname = data;
243 xd->xvalue = data + xd->name_len+1;
244
245 c->xdatum_mem_usage += length;
246
247 xd->hashkey = xattr_datum_hashkey(xprefix: xd->xprefix, xname: xd->xname, xvalue: xd->xvalue, xsize: xd->value_len);
248 i = xd->hashkey % XATTRINDEX_HASHSIZE;
249 list_add(new: &xd->xindex, head: &c->xattrindex[i]);
250 if (!retry) {
251 retry = 1;
252 reclaim_xattr_datum(c);
253 if (!xd->xname)
254 goto retry;
255 }
256
257 dbg_xattr("success on loading xdatum (xid=%u, xprefix=%u, xname='%s')\n",
258 xd->xid, xd->xprefix, xd->xname);
259
260 return 0;
261}
262
263static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
264{
265 /* must be called under down_write(xattr_sem);
266 * rc < 0 : recoverable error, try again
267 * rc = 0 : success
268 * rc > 0 : Unrecoverable error, this node should be deleted.
269 */
270 int rc = 0;
271
272 BUG_ON(xd->flags & JFFS2_XFLAGS_DEAD);
273 if (xd->xname)
274 return 0;
275 if (xd->flags & JFFS2_XFLAGS_INVALID)
276 return JFFS2_XATTR_IS_CORRUPTED;
277 if (unlikely(is_xattr_datum_unchecked(c, xd)))
278 rc = do_verify_xattr_datum(c, xd);
279 if (!rc)
280 rc = do_load_xattr_datum(c, xd);
281 return rc;
282}
283
284static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
285{
286 /* must be called under down_write(xattr_sem) */
287 struct jffs2_raw_xattr rx;
288 struct kvec vecs[2];
289 size_t length;
290 int rc, totlen;
291 uint32_t phys_ofs = write_ofs(c);
292
293 BUG_ON(!xd->xname);
294 BUG_ON(xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID));
295
296 vecs[0].iov_base = &rx;
297 vecs[0].iov_len = sizeof(rx);
298 vecs[1].iov_base = xd->xname;
299 vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
300 totlen = vecs[0].iov_len + vecs[1].iov_len;
301
302 /* Setup raw-xattr */
303 memset(&rx, 0, sizeof(rx));
304 rx.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
305 rx.nodetype = cpu_to_je16(JFFS2_NODETYPE_XATTR);
306 rx.totlen = cpu_to_je32(PAD(totlen));
307 rx.hdr_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_unknown_node) - 4));
308
309 rx.xid = cpu_to_je32(xd->xid);
310 rx.version = cpu_to_je32(++xd->version);
311 rx.xprefix = xd->xprefix;
312 rx.name_len = xd->name_len;
313 rx.value_len = cpu_to_je16(xd->value_len);
314 rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
315 rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
316
317 rc = jffs2_flash_writev(c, vecs, count: 2, to: phys_ofs, retlen: &length, ino: 0);
318 if (rc || totlen != length) {
319 JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%zu, at %#08x\n",
320 rc, totlen, length, phys_ofs);
321 rc = rc ? rc : -EIO;
322 if (length)
323 jffs2_add_physical_node_ref(c, ofs: phys_ofs | REF_OBSOLETE, PAD(totlen), NULL);
324
325 return rc;
326 }
327 /* success */
328 jffs2_add_physical_node_ref(c, ofs: phys_ofs | REF_PRISTINE, PAD(totlen), ic: (void *)xd);
329
330 dbg_xattr("success on saving xdatum (xid=%u, version=%u, xprefix=%u, xname='%s')\n",
331 xd->xid, xd->version, xd->xprefix, xd->xname);
332
333 return 0;
334}
335
336static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
337 int xprefix, const char *xname,
338 const char *xvalue, int xsize)
339{
340 /* must be called under down_write(xattr_sem) */
341 struct jffs2_xattr_datum *xd;
342 uint32_t hashkey, name_len;
343 char *data;
344 int i, rc;
345
346 /* Search xattr_datum has same xname/xvalue by index */
347 hashkey = xattr_datum_hashkey(xprefix, xname, xvalue, xsize);
348 i = hashkey % XATTRINDEX_HASHSIZE;
349 list_for_each_entry(xd, &c->xattrindex[i], xindex) {
350 if (xd->hashkey==hashkey
351 && xd->xprefix==xprefix
352 && xd->value_len==xsize
353 && !strcmp(xd->xname, xname)
354 && !memcmp(p: xd->xvalue, q: xvalue, size: xsize)) {
355 atomic_inc(v: &xd->refcnt);
356 return xd;
357 }
358 }
359
360 /* Not found, Create NEW XATTR-Cache */
361 name_len = strlen(xname);
362
363 xd = jffs2_alloc_xattr_datum();
364 if (!xd)
365 return ERR_PTR(error: -ENOMEM);
366
367 data = kmalloc(size: name_len + 1 + xsize, GFP_KERNEL);
368 if (!data) {
369 jffs2_free_xattr_datum(xd);
370 return ERR_PTR(error: -ENOMEM);
371 }
372 strcpy(p: data, q: xname);
373 memcpy(data + name_len + 1, xvalue, xsize);
374
375 atomic_set(v: &xd->refcnt, i: 1);
376 xd->xid = ++c->highest_xid;
377 xd->flags |= JFFS2_XFLAGS_HOT;
378 xd->xprefix = xprefix;
379
380 xd->hashkey = hashkey;
381 xd->xname = data;
382 xd->xvalue = data + name_len + 1;
383 xd->name_len = name_len;
384 xd->value_len = xsize;
385 xd->data_crc = crc32(0, data, xd->name_len + 1 + xd->value_len);
386
387 rc = save_xattr_datum(c, xd);
388 if (rc) {
389 kfree(objp: xd->xname);
390 jffs2_free_xattr_datum(xd);
391 return ERR_PTR(error: rc);
392 }
393
394 /* Insert Hash Index */
395 i = hashkey % XATTRINDEX_HASHSIZE;
396 list_add(new: &xd->xindex, head: &c->xattrindex[i]);
397
398 c->xdatum_mem_usage += (xd->name_len + 1 + xd->value_len);
399 reclaim_xattr_datum(c);
400
401 return xd;
402}
403
404static void unrefer_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
405{
406 /* must be called under down_write(xattr_sem) */
407 if (atomic_dec_and_lock(&xd->refcnt, &c->erase_completion_lock)) {
408 unload_xattr_datum(c, xd);
409 xd->flags |= JFFS2_XFLAGS_DEAD;
410 if (xd->node == (void *)xd) {
411 BUG_ON(!(xd->flags & JFFS2_XFLAGS_INVALID));
412 jffs2_free_xattr_datum(xd);
413 } else {
414 list_add(new: &xd->xindex, head: &c->xattr_dead_list);
415 }
416 spin_unlock(lock: &c->erase_completion_lock);
417
418 dbg_xattr("xdatum(xid=%u, version=%u) was removed.\n",
419 xd->xid, xd->version);
420 }
421}
422
423/* -------- xref related functions ------------------
424 * verify_xattr_ref(c, ref)
425 * is used to load xref information from medium. Because summary data does not
426 * contain xid/ino, it's necessary to verify once while mounting process.
427 * save_xattr_ref(c, ref)
428 * is used to write xref to medium. If delete marker is marked, it write
429 * a delete marker of xref into medium.
430 * create_xattr_ref(c, ic, xd)
431 * is used to create a new xref and write to medium.
432 * delete_xattr_ref(c, ref)
433 * is used to delete jffs2_xattr_ref. It marks xref XREF_DELETE_MARKER,
434 * and allows GC to reclaim those physical nodes.
435 * jffs2_xattr_delete_inode(c, ic)
436 * is called to remove xrefs related to obsolete inode when inode is unlinked.
437 * jffs2_xattr_free_inode(c, ic)
438 * is called to release xattr related objects when unmounting.
439 * check_xattr_ref_inode(c, ic)
440 * is used to confirm inode does not have duplicate xattr name/value pair.
441 * jffs2_xattr_do_crccheck_inode(c, ic)
442 * is used to force xattr data integrity check during the initial gc scan.
443 * -------------------------------------------------- */
444static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
445{
446 struct jffs2_eraseblock *jeb;
447 struct jffs2_raw_node_ref *raw;
448 struct jffs2_raw_xref rr;
449 size_t readlen;
450 uint32_t crc, offset, totlen;
451 int rc;
452
453 spin_lock(lock: &c->erase_completion_lock);
454 if (ref_flags(ref->node) != REF_UNCHECKED)
455 goto complete;
456 offset = ref_offset(ref->node);
457 spin_unlock(lock: &c->erase_completion_lock);
458
459 rc = jffs2_flash_read(c, ofs: offset, len: sizeof(rr), retlen: &readlen, buf: (char *)&rr);
460 if (rc || sizeof(rr) != readlen) {
461 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu, at %#08x\n",
462 rc, sizeof(rr), readlen, offset);
463 return rc ? rc : -EIO;
464 }
465 /* obsolete node */
466 crc = crc32(0, &rr, sizeof(rr) - 4);
467 if (crc != je32_to_cpu(rr.node_crc)) {
468 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
469 offset, je32_to_cpu(rr.node_crc), crc);
470 return JFFS2_XATTR_IS_CORRUPTED;
471 }
472 if (je16_to_cpu(rr.magic) != JFFS2_MAGIC_BITMASK
473 || je16_to_cpu(rr.nodetype) != JFFS2_NODETYPE_XREF
474 || je32_to_cpu(rr.totlen) != PAD(sizeof(rr))) {
475 JFFS2_ERROR("inconsistent xref at %#08x, magic=%#04x/%#04x, "
476 "nodetype=%#04x/%#04x, totlen=%u/%zu\n",
477 offset, je16_to_cpu(rr.magic), JFFS2_MAGIC_BITMASK,
478 je16_to_cpu(rr.nodetype), JFFS2_NODETYPE_XREF,
479 je32_to_cpu(rr.totlen), PAD(sizeof(rr)));
480 return JFFS2_XATTR_IS_CORRUPTED;
481 }
482 ref->ino = je32_to_cpu(rr.ino);
483 ref->xid = je32_to_cpu(rr.xid);
484 ref->xseqno = je32_to_cpu(rr.xseqno);
485 if (ref->xseqno > c->highest_xseqno)
486 c->highest_xseqno = (ref->xseqno & ~XREF_DELETE_MARKER);
487
488 spin_lock(lock: &c->erase_completion_lock);
489 complete:
490 for (raw=ref->node; raw != (void *)ref; raw=raw->next_in_ino) {
491 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
492 totlen = PAD(ref_totlen(c, jeb, raw));
493 if (ref_flags(raw) == REF_UNCHECKED) {
494 c->unchecked_size -= totlen; c->used_size += totlen;
495 jeb->unchecked_size -= totlen; jeb->used_size += totlen;
496 }
497 raw->flash_offset = ref_offset(raw) | ((ref->node==raw) ? REF_PRISTINE : REF_NORMAL);
498 }
499 spin_unlock(lock: &c->erase_completion_lock);
500
501 dbg_xattr("success on verifying xref (ino=%u, xid=%u) at %#08x\n",
502 ref->ino, ref->xid, ref_offset(ref->node));
503 return 0;
504}
505
506static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
507{
508 /* must be called under down_write(xattr_sem) */
509 struct jffs2_raw_xref rr;
510 size_t length;
511 uint32_t xseqno, phys_ofs = write_ofs(c);
512 int ret;
513
514 rr.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
515 rr.nodetype = cpu_to_je16(JFFS2_NODETYPE_XREF);
516 rr.totlen = cpu_to_je32(PAD(sizeof(rr)));
517 rr.hdr_crc = cpu_to_je32(crc32(0, &rr, sizeof(struct jffs2_unknown_node) - 4));
518
519 xseqno = (c->highest_xseqno += 2);
520 if (is_xattr_ref_dead(ref)) {
521 xseqno |= XREF_DELETE_MARKER;
522 rr.ino = cpu_to_je32(ref->ino);
523 rr.xid = cpu_to_je32(ref->xid);
524 } else {
525 rr.ino = cpu_to_je32(ref->ic->ino);
526 rr.xid = cpu_to_je32(ref->xd->xid);
527 }
528 rr.xseqno = cpu_to_je32(xseqno);
529 rr.node_crc = cpu_to_je32(crc32(0, &rr, sizeof(rr) - 4));
530
531 ret = jffs2_flash_write(c, ofs: phys_ofs, len: sizeof(rr), retlen: &length, buf: (char *)&rr);
532 if (ret || sizeof(rr) != length) {
533 JFFS2_WARNING("jffs2_flash_write() returned %d, request=%zu, retlen=%zu, at %#08x\n",
534 ret, sizeof(rr), length, phys_ofs);
535 ret = ret ? ret : -EIO;
536 if (length)
537 jffs2_add_physical_node_ref(c, ofs: phys_ofs | REF_OBSOLETE, PAD(sizeof(rr)), NULL);
538
539 return ret;
540 }
541 /* success */
542 ref->xseqno = xseqno;
543 jffs2_add_physical_node_ref(c, ofs: phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), ic: (void *)ref);
544
545 dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid);
546
547 return 0;
548}
549
550static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic,
551 struct jffs2_xattr_datum *xd)
552{
553 /* must be called under down_write(xattr_sem) */
554 struct jffs2_xattr_ref *ref;
555 int ret;
556
557 ref = jffs2_alloc_xattr_ref();
558 if (!ref)
559 return ERR_PTR(error: -ENOMEM);
560 ref->ic = ic;
561 ref->xd = xd;
562
563 ret = save_xattr_ref(c, ref);
564 if (ret) {
565 jffs2_free_xattr_ref(ref);
566 return ERR_PTR(error: ret);
567 }
568
569 /* Chain to inode */
570 ref->next = ic->xref;
571 ic->xref = ref;
572
573 return ref; /* success */
574}
575
576static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
577{
578 /* must be called under down_write(xattr_sem) */
579 struct jffs2_xattr_datum *xd;
580
581 xd = ref->xd;
582 ref->xseqno |= XREF_DELETE_MARKER;
583 ref->ino = ref->ic->ino;
584 ref->xid = ref->xd->xid;
585 spin_lock(lock: &c->erase_completion_lock);
586 ref->next = c->xref_dead_list;
587 c->xref_dead_list = ref;
588 spin_unlock(lock: &c->erase_completion_lock);
589
590 dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) was removed.\n",
591 ref->ino, ref->xid, ref->xseqno);
592
593 unrefer_xattr_datum(c, xd);
594}
595
596void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
597{
598 /* It's called from jffs2_evict_inode() on inode removing.
599 When an inode with XATTR is removed, those XATTRs must be removed. */
600 struct jffs2_xattr_ref *ref, *_ref;
601
602 if (!ic || ic->pino_nlink > 0)
603 return;
604
605 down_write(sem: &c->xattr_sem);
606 for (ref = ic->xref; ref; ref = _ref) {
607 _ref = ref->next;
608 delete_xattr_ref(c, ref);
609 }
610 ic->xref = NULL;
611 up_write(sem: &c->xattr_sem);
612}
613
614void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
615{
616 /* It's called from jffs2_free_ino_caches() until unmounting FS. */
617 struct jffs2_xattr_datum *xd;
618 struct jffs2_xattr_ref *ref, *_ref;
619
620 down_write(sem: &c->xattr_sem);
621 for (ref = ic->xref; ref; ref = _ref) {
622 _ref = ref->next;
623 xd = ref->xd;
624 if (atomic_dec_and_test(v: &xd->refcnt)) {
625 unload_xattr_datum(c, xd);
626 jffs2_free_xattr_datum(xd);
627 }
628 jffs2_free_xattr_ref(ref);
629 }
630 ic->xref = NULL;
631 up_write(sem: &c->xattr_sem);
632}
633
634static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
635{
636 /* success of check_xattr_ref_inode() means that inode (ic) dose not have
637 * duplicate name/value pairs. If duplicate name/value pair would be found,
638 * one will be removed.
639 */
640 struct jffs2_xattr_ref *ref, *cmp, **pref, **pcmp;
641 int rc = 0;
642
643 if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
644 return 0;
645 down_write(sem: &c->xattr_sem);
646 retry:
647 rc = 0;
648 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
649 if (!ref->xd->xname) {
650 rc = load_xattr_datum(c, xd: ref->xd);
651 if (unlikely(rc > 0)) {
652 *pref = ref->next;
653 delete_xattr_ref(c, ref);
654 goto retry;
655 } else if (unlikely(rc < 0))
656 goto out;
657 }
658 for (cmp=ref->next, pcmp=&ref->next; cmp; pcmp=&cmp->next, cmp=cmp->next) {
659 if (!cmp->xd->xname) {
660 ref->xd->flags |= JFFS2_XFLAGS_BIND;
661 rc = load_xattr_datum(c, xd: cmp->xd);
662 ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
663 if (unlikely(rc > 0)) {
664 *pcmp = cmp->next;
665 delete_xattr_ref(c, ref: cmp);
666 goto retry;
667 } else if (unlikely(rc < 0))
668 goto out;
669 }
670 if (ref->xd->xprefix == cmp->xd->xprefix
671 && !strcmp(ref->xd->xname, cmp->xd->xname)) {
672 if (ref->xseqno > cmp->xseqno) {
673 *pcmp = cmp->next;
674 delete_xattr_ref(c, ref: cmp);
675 } else {
676 *pref = ref->next;
677 delete_xattr_ref(c, ref);
678 }
679 goto retry;
680 }
681 }
682 }
683 ic->flags |= INO_FLAGS_XATTR_CHECKED;
684 out:
685 up_write(sem: &c->xattr_sem);
686
687 return rc;
688}
689
690void jffs2_xattr_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
691{
692 check_xattr_ref_inode(c, ic);
693}
694
695/* -------- xattr subsystem functions ---------------
696 * jffs2_init_xattr_subsystem(c)
697 * is used to initialize semaphore and list_head, and some variables.
698 * jffs2_find_xattr_datum(c, xid)
699 * is used to lookup xdatum while scanning process.
700 * jffs2_clear_xattr_subsystem(c)
701 * is used to release any xattr related objects.
702 * jffs2_build_xattr_subsystem(c)
703 * is used to associate xdatum and xref while super block building process.
704 * jffs2_setup_xattr_datum(c, xid, version)
705 * is used to insert xdatum while scanning process.
706 * -------------------------------------------------- */
707void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
708{
709 int i;
710
711 for (i=0; i < XATTRINDEX_HASHSIZE; i++)
712 INIT_LIST_HEAD(list: &c->xattrindex[i]);
713 INIT_LIST_HEAD(list: &c->xattr_unchecked);
714 INIT_LIST_HEAD(list: &c->xattr_dead_list);
715 c->xref_dead_list = NULL;
716 c->xref_temp = NULL;
717
718 init_rwsem(&c->xattr_sem);
719 c->highest_xid = 0;
720 c->highest_xseqno = 0;
721 c->xdatum_mem_usage = 0;
722 c->xdatum_mem_threshold = 32 * 1024; /* Default 32KB */
723}
724
725static struct jffs2_xattr_datum *jffs2_find_xattr_datum(struct jffs2_sb_info *c, uint32_t xid)
726{
727 struct jffs2_xattr_datum *xd;
728 int i = xid % XATTRINDEX_HASHSIZE;
729
730 /* It's only used in scanning/building process. */
731 BUG_ON(!(c->flags & (JFFS2_SB_FLAG_SCANNING|JFFS2_SB_FLAG_BUILDING)));
732
733 list_for_each_entry(xd, &c->xattrindex[i], xindex) {
734 if (xd->xid==xid)
735 return xd;
736 }
737 return NULL;
738}
739
740void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
741{
742 struct jffs2_xattr_datum *xd, *_xd;
743 struct jffs2_xattr_ref *ref, *_ref;
744 int i;
745
746 for (ref=c->xref_temp; ref; ref = _ref) {
747 _ref = ref->next;
748 jffs2_free_xattr_ref(ref);
749 }
750
751 for (ref=c->xref_dead_list; ref; ref = _ref) {
752 _ref = ref->next;
753 jffs2_free_xattr_ref(ref);
754 }
755
756 for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
757 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
758 list_del(entry: &xd->xindex);
759 kfree(objp: xd->xname);
760 jffs2_free_xattr_datum(xd);
761 }
762 }
763
764 list_for_each_entry_safe(xd, _xd, &c->xattr_dead_list, xindex) {
765 list_del(entry: &xd->xindex);
766 jffs2_free_xattr_datum(xd);
767 }
768 list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
769 list_del(entry: &xd->xindex);
770 jffs2_free_xattr_datum(xd);
771 }
772}
773
774#define XREF_TMPHASH_SIZE (128)
775int jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
776{
777 struct jffs2_xattr_ref *ref, *_ref;
778 struct jffs2_xattr_ref **xref_tmphash;
779 struct jffs2_xattr_datum *xd, *_xd;
780 struct jffs2_inode_cache *ic;
781 struct jffs2_raw_node_ref *raw;
782 int i, xdatum_count = 0, xdatum_unchecked_count = 0, xref_count = 0;
783 int xdatum_orphan_count = 0, xref_orphan_count = 0, xref_dead_count = 0;
784
785 BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
786
787 xref_tmphash = kcalloc(XREF_TMPHASH_SIZE,
788 size: sizeof(struct jffs2_xattr_ref *), GFP_KERNEL);
789 if (!xref_tmphash)
790 return -ENOMEM;
791
792 /* Phase.1 : Merge same xref */
793 for (ref=c->xref_temp; ref; ref=_ref) {
794 struct jffs2_xattr_ref *tmp;
795
796 _ref = ref->next;
797 if (ref_flags(ref->node) != REF_PRISTINE) {
798 if (verify_xattr_ref(c, ref)) {
799 BUG_ON(ref->node->next_in_ino != (void *)ref);
800 ref->node->next_in_ino = NULL;
801 jffs2_mark_node_obsolete(c, raw: ref->node);
802 jffs2_free_xattr_ref(ref);
803 continue;
804 }
805 }
806
807 i = (ref->ino ^ ref->xid) % XREF_TMPHASH_SIZE;
808 for (tmp=xref_tmphash[i]; tmp; tmp=tmp->next) {
809 if (tmp->ino == ref->ino && tmp->xid == ref->xid)
810 break;
811 }
812 if (tmp) {
813 raw = ref->node;
814 if (ref->xseqno > tmp->xseqno) {
815 tmp->xseqno = ref->xseqno;
816 raw->next_in_ino = tmp->node;
817 tmp->node = raw;
818 } else {
819 raw->next_in_ino = tmp->node->next_in_ino;
820 tmp->node->next_in_ino = raw;
821 }
822 jffs2_free_xattr_ref(ref);
823 continue;
824 } else {
825 ref->next = xref_tmphash[i];
826 xref_tmphash[i] = ref;
827 }
828 }
829 c->xref_temp = NULL;
830
831 /* Phase.2 : Bind xref with inode_cache and xattr_datum */
832 for (i=0; i < XREF_TMPHASH_SIZE; i++) {
833 for (ref=xref_tmphash[i]; ref; ref=_ref) {
834 xref_count++;
835 _ref = ref->next;
836 if (is_xattr_ref_dead(ref)) {
837 ref->next = c->xref_dead_list;
838 c->xref_dead_list = ref;
839 xref_dead_count++;
840 continue;
841 }
842 /* At this point, ref->xid and ref->ino contain XID and inode number.
843 ref->xd and ref->ic are not valid yet. */
844 xd = jffs2_find_xattr_datum(c, xid: ref->xid);
845 ic = jffs2_get_ino_cache(c, ino: ref->ino);
846 if (!xd || !ic || !ic->pino_nlink) {
847 dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) is orphan.\n",
848 ref->ino, ref->xid, ref->xseqno);
849 ref->xseqno |= XREF_DELETE_MARKER;
850 ref->next = c->xref_dead_list;
851 c->xref_dead_list = ref;
852 xref_orphan_count++;
853 continue;
854 }
855 ref->xd = xd;
856 ref->ic = ic;
857 atomic_inc(v: &xd->refcnt);
858 ref->next = ic->xref;
859 ic->xref = ref;
860 }
861 }
862
863 /* Phase.3 : Link unchecked xdatum to xattr_unchecked list */
864 for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
865 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
866 xdatum_count++;
867 list_del_init(entry: &xd->xindex);
868 if (!atomic_read(v: &xd->refcnt)) {
869 dbg_xattr("xdatum(xid=%u, version=%u) is orphan.\n",
870 xd->xid, xd->version);
871 xd->flags |= JFFS2_XFLAGS_DEAD;
872 list_add(new: &xd->xindex, head: &c->xattr_unchecked);
873 xdatum_orphan_count++;
874 continue;
875 }
876 if (is_xattr_datum_unchecked(c, xd)) {
877 dbg_xattr("unchecked xdatum(xid=%u, version=%u)\n",
878 xd->xid, xd->version);
879 list_add(new: &xd->xindex, head: &c->xattr_unchecked);
880 xdatum_unchecked_count++;
881 }
882 }
883 }
884 /* build complete */
885 JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum"
886 " (%u unchecked, %u orphan) and "
887 "%u of xref (%u dead, %u orphan) found.\n",
888 xdatum_count, xdatum_unchecked_count, xdatum_orphan_count,
889 xref_count, xref_dead_count, xref_orphan_count);
890 kfree(objp: xref_tmphash);
891 return 0;
892}
893
894struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
895 uint32_t xid, uint32_t version)
896{
897 struct jffs2_xattr_datum *xd;
898
899 xd = jffs2_find_xattr_datum(c, xid);
900 if (!xd) {
901 xd = jffs2_alloc_xattr_datum();
902 if (!xd)
903 return ERR_PTR(error: -ENOMEM);
904 xd->xid = xid;
905 xd->version = version;
906 if (xd->xid > c->highest_xid)
907 c->highest_xid = xd->xid;
908 list_add_tail(new: &xd->xindex, head: &c->xattrindex[xid % XATTRINDEX_HASHSIZE]);
909 }
910 return xd;
911}
912
913/* -------- xattr subsystem functions ---------------
914 * xprefix_to_handler(xprefix)
915 * is used to translate xprefix into xattr_handler.
916 * jffs2_listxattr(dentry, buffer, size)
917 * is an implementation of listxattr handler on jffs2.
918 * do_jffs2_getxattr(inode, xprefix, xname, buffer, size)
919 * is an implementation of getxattr handler on jffs2.
920 * do_jffs2_setxattr(inode, xprefix, xname, buffer, size, flags)
921 * is an implementation of setxattr handler on jffs2.
922 * -------------------------------------------------- */
923const struct xattr_handler * const jffs2_xattr_handlers[] = {
924 &jffs2_user_xattr_handler,
925#ifdef CONFIG_JFFS2_FS_SECURITY
926 &jffs2_security_xattr_handler,
927#endif
928 &jffs2_trusted_xattr_handler,
929 NULL
930};
931
932static const char *jffs2_xattr_prefix(int xprefix, struct dentry *dentry)
933{
934 const struct xattr_handler *ret = NULL;
935
936 switch (xprefix) {
937 case JFFS2_XPREFIX_USER:
938 ret = &jffs2_user_xattr_handler;
939 break;
940#ifdef CONFIG_JFFS2_FS_SECURITY
941 case JFFS2_XPREFIX_SECURITY:
942 ret = &jffs2_security_xattr_handler;
943 break;
944#endif
945#ifdef CONFIG_JFFS2_FS_POSIX_ACL
946 case JFFS2_XPREFIX_ACL_ACCESS:
947 ret = &nop_posix_acl_access;
948 break;
949 case JFFS2_XPREFIX_ACL_DEFAULT:
950 ret = &nop_posix_acl_default;
951 break;
952#endif
953 case JFFS2_XPREFIX_TRUSTED:
954 ret = &jffs2_trusted_xattr_handler;
955 break;
956 default:
957 return NULL;
958 }
959
960 if (!xattr_handler_can_list(handler: ret, dentry))
961 return NULL;
962
963 return xattr_prefix(handler: ret);
964}
965
966ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
967{
968 struct inode *inode = d_inode(dentry);
969 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
970 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
971 struct jffs2_inode_cache *ic = f->inocache;
972 struct jffs2_xattr_ref *ref, **pref;
973 struct jffs2_xattr_datum *xd;
974 const char *prefix;
975 ssize_t prefix_len, len, rc;
976 int retry = 0;
977
978 rc = check_xattr_ref_inode(c, ic);
979 if (unlikely(rc))
980 return rc;
981
982 down_read(sem: &c->xattr_sem);
983 retry:
984 len = 0;
985 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
986 BUG_ON(ref->ic != ic);
987 xd = ref->xd;
988 if (!xd->xname) {
989 /* xdatum is unchached */
990 if (!retry) {
991 retry = 1;
992 up_read(sem: &c->xattr_sem);
993 down_write(sem: &c->xattr_sem);
994 goto retry;
995 } else {
996 rc = load_xattr_datum(c, xd);
997 if (unlikely(rc > 0)) {
998 *pref = ref->next;
999 delete_xattr_ref(c, ref);
1000 goto retry;
1001 } else if (unlikely(rc < 0))
1002 goto out;
1003 }
1004 }
1005
1006 prefix = jffs2_xattr_prefix(xprefix: xd->xprefix, dentry);
1007 if (!prefix)
1008 continue;
1009 prefix_len = strlen(prefix);
1010 rc = prefix_len + xd->name_len + 1;
1011
1012 if (buffer) {
1013 if (rc > size - len) {
1014 rc = -ERANGE;
1015 goto out;
1016 }
1017 memcpy(buffer, prefix, prefix_len);
1018 buffer += prefix_len;
1019 memcpy(buffer, xd->xname, xd->name_len);
1020 buffer += xd->name_len;
1021 *buffer++ = 0;
1022 }
1023 len += rc;
1024 }
1025 rc = len;
1026 out:
1027 if (!retry) {
1028 up_read(sem: &c->xattr_sem);
1029 } else {
1030 up_write(sem: &c->xattr_sem);
1031 }
1032 return rc;
1033}
1034
1035int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
1036 char *buffer, size_t size)
1037{
1038 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1039 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1040 struct jffs2_inode_cache *ic = f->inocache;
1041 struct jffs2_xattr_datum *xd;
1042 struct jffs2_xattr_ref *ref, **pref;
1043 int rc, retry = 0;
1044
1045 rc = check_xattr_ref_inode(c, ic);
1046 if (unlikely(rc))
1047 return rc;
1048
1049 down_read(sem: &c->xattr_sem);
1050 retry:
1051 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1052 BUG_ON(ref->ic!=ic);
1053
1054 xd = ref->xd;
1055 if (xd->xprefix != xprefix)
1056 continue;
1057 if (!xd->xname) {
1058 /* xdatum is unchached */
1059 if (!retry) {
1060 retry = 1;
1061 up_read(sem: &c->xattr_sem);
1062 down_write(sem: &c->xattr_sem);
1063 goto retry;
1064 } else {
1065 rc = load_xattr_datum(c, xd);
1066 if (unlikely(rc > 0)) {
1067 *pref = ref->next;
1068 delete_xattr_ref(c, ref);
1069 goto retry;
1070 } else if (unlikely(rc < 0)) {
1071 goto out;
1072 }
1073 }
1074 }
1075 if (!strcmp(xname, xd->xname)) {
1076 rc = xd->value_len;
1077 if (buffer) {
1078 if (size < rc) {
1079 rc = -ERANGE;
1080 } else {
1081 memcpy(buffer, xd->xvalue, rc);
1082 }
1083 }
1084 goto out;
1085 }
1086 }
1087 rc = -ENODATA;
1088 out:
1089 if (!retry) {
1090 up_read(sem: &c->xattr_sem);
1091 } else {
1092 up_write(sem: &c->xattr_sem);
1093 }
1094 return rc;
1095}
1096
1097int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
1098 const char *buffer, size_t size, int flags)
1099{
1100 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1101 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1102 struct jffs2_inode_cache *ic = f->inocache;
1103 struct jffs2_xattr_datum *xd;
1104 struct jffs2_xattr_ref *ref, *newref, **pref;
1105 uint32_t length, request;
1106 int rc;
1107
1108 rc = check_xattr_ref_inode(c, ic);
1109 if (unlikely(rc))
1110 return rc;
1111
1112 request = PAD(sizeof(struct jffs2_raw_xattr) + strlen(xname) + 1 + size);
1113 rc = jffs2_reserve_space(c, minsize: request, len: &length,
1114 ALLOC_NORMAL, JFFS2_SUMMARY_XATTR_SIZE);
1115 if (rc) {
1116 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1117 return rc;
1118 }
1119
1120 /* Find existing xattr */
1121 down_write(sem: &c->xattr_sem);
1122 retry:
1123 for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1124 xd = ref->xd;
1125 if (xd->xprefix != xprefix)
1126 continue;
1127 if (!xd->xname) {
1128 rc = load_xattr_datum(c, xd);
1129 if (unlikely(rc > 0)) {
1130 *pref = ref->next;
1131 delete_xattr_ref(c, ref);
1132 goto retry;
1133 } else if (unlikely(rc < 0))
1134 goto out;
1135 }
1136 if (!strcmp(xd->xname, xname)) {
1137 if (flags & XATTR_CREATE) {
1138 rc = -EEXIST;
1139 goto out;
1140 }
1141 if (!buffer) {
1142 ref->ino = ic->ino;
1143 ref->xid = xd->xid;
1144 ref->xseqno |= XREF_DELETE_MARKER;
1145 rc = save_xattr_ref(c, ref);
1146 if (!rc) {
1147 *pref = ref->next;
1148 spin_lock(lock: &c->erase_completion_lock);
1149 ref->next = c->xref_dead_list;
1150 c->xref_dead_list = ref;
1151 spin_unlock(lock: &c->erase_completion_lock);
1152 unrefer_xattr_datum(c, xd);
1153 } else {
1154 ref->ic = ic;
1155 ref->xd = xd;
1156 ref->xseqno &= ~XREF_DELETE_MARKER;
1157 }
1158 goto out;
1159 }
1160 goto found;
1161 }
1162 }
1163 /* not found */
1164 if (flags & XATTR_REPLACE) {
1165 rc = -ENODATA;
1166 goto out;
1167 }
1168 if (!buffer) {
1169 rc = -ENODATA;
1170 goto out;
1171 }
1172 found:
1173 xd = create_xattr_datum(c, xprefix, xname, xvalue: buffer, xsize: size);
1174 if (IS_ERR(ptr: xd)) {
1175 rc = PTR_ERR(ptr: xd);
1176 goto out;
1177 }
1178 up_write(sem: &c->xattr_sem);
1179 jffs2_complete_reservation(c);
1180
1181 /* create xattr_ref */
1182 request = PAD(sizeof(struct jffs2_raw_xref));
1183 rc = jffs2_reserve_space(c, minsize: request, len: &length,
1184 ALLOC_NORMAL, JFFS2_SUMMARY_XREF_SIZE);
1185 down_write(sem: &c->xattr_sem);
1186 if (rc) {
1187 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1188 unrefer_xattr_datum(c, xd);
1189 up_write(sem: &c->xattr_sem);
1190 return rc;
1191 }
1192 if (ref)
1193 *pref = ref->next;
1194 newref = create_xattr_ref(c, ic, xd);
1195 if (IS_ERR(ptr: newref)) {
1196 if (ref) {
1197 ref->next = ic->xref;
1198 ic->xref = ref;
1199 }
1200 rc = PTR_ERR(ptr: newref);
1201 unrefer_xattr_datum(c, xd);
1202 } else if (ref) {
1203 delete_xattr_ref(c, ref);
1204 }
1205 out:
1206 up_write(sem: &c->xattr_sem);
1207 jffs2_complete_reservation(c);
1208 return rc;
1209}
1210
1211/* -------- garbage collector functions -------------
1212 * jffs2_garbage_collect_xattr_datum(c, xd, raw)
1213 * is used to move xdatum into new node.
1214 * jffs2_garbage_collect_xattr_ref(c, ref, raw)
1215 * is used to move xref into new node.
1216 * jffs2_verify_xattr(c)
1217 * is used to call do_verify_xattr_datum() before garbage collecting.
1218 * jffs2_release_xattr_datum(c, xd)
1219 * is used to release an in-memory object of xdatum.
1220 * jffs2_release_xattr_ref(c, ref)
1221 * is used to release an in-memory object of xref.
1222 * -------------------------------------------------- */
1223int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
1224 struct jffs2_raw_node_ref *raw)
1225{
1226 uint32_t totlen, length, old_ofs;
1227 int rc = 0;
1228
1229 down_write(sem: &c->xattr_sem);
1230 if (xd->node != raw)
1231 goto out;
1232 if (xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID))
1233 goto out;
1234
1235 rc = load_xattr_datum(c, xd);
1236 if (unlikely(rc)) {
1237 rc = (rc > 0) ? 0 : rc;
1238 goto out;
1239 }
1240 old_ofs = ref_offset(xd->node);
1241 totlen = PAD(sizeof(struct jffs2_raw_xattr)
1242 + xd->name_len + 1 + xd->value_len);
1243 rc = jffs2_reserve_space_gc(c, minsize: totlen, len: &length, JFFS2_SUMMARY_XATTR_SIZE);
1244 if (rc) {
1245 JFFS2_WARNING("jffs2_reserve_space_gc()=%d, request=%u\n", rc, totlen);
1246 goto out;
1247 }
1248 rc = save_xattr_datum(c, xd);
1249 if (!rc)
1250 dbg_xattr("xdatum (xid=%u, version=%u) GC'ed from %#08x to %08x\n",
1251 xd->xid, xd->version, old_ofs, ref_offset(xd->node));
1252 out:
1253 if (!rc)
1254 jffs2_mark_node_obsolete(c, raw);
1255 up_write(sem: &c->xattr_sem);
1256 return rc;
1257}
1258
1259int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
1260 struct jffs2_raw_node_ref *raw)
1261{
1262 uint32_t totlen, length, old_ofs;
1263 int rc = 0;
1264
1265 down_write(sem: &c->xattr_sem);
1266 BUG_ON(!ref->node);
1267
1268 if (ref->node != raw)
1269 goto out;
1270 if (is_xattr_ref_dead(ref) && (raw->next_in_ino == (void *)ref))
1271 goto out;
1272
1273 old_ofs = ref_offset(ref->node);
1274 totlen = ref_totlen(c, c->gcblock, ref->node);
1275
1276 rc = jffs2_reserve_space_gc(c, minsize: totlen, len: &length, JFFS2_SUMMARY_XREF_SIZE);
1277 if (rc) {
1278 JFFS2_WARNING("%s: jffs2_reserve_space_gc() = %d, request = %u\n",
1279 __func__, rc, totlen);
1280 goto out;
1281 }
1282 rc = save_xattr_ref(c, ref);
1283 if (!rc)
1284 dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n",
1285 ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node));
1286 out:
1287 if (!rc)
1288 jffs2_mark_node_obsolete(c, raw);
1289 up_write(sem: &c->xattr_sem);
1290 return rc;
1291}
1292
1293int jffs2_verify_xattr(struct jffs2_sb_info *c)
1294{
1295 struct jffs2_xattr_datum *xd, *_xd;
1296 struct jffs2_eraseblock *jeb;
1297 struct jffs2_raw_node_ref *raw;
1298 uint32_t totlen;
1299 int rc;
1300
1301 down_write(sem: &c->xattr_sem);
1302 list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
1303 rc = do_verify_xattr_datum(c, xd);
1304 if (rc < 0)
1305 continue;
1306 list_del_init(entry: &xd->xindex);
1307 spin_lock(lock: &c->erase_completion_lock);
1308 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
1309 if (ref_flags(raw) != REF_UNCHECKED)
1310 continue;
1311 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
1312 totlen = PAD(ref_totlen(c, jeb, raw));
1313 c->unchecked_size -= totlen; c->used_size += totlen;
1314 jeb->unchecked_size -= totlen; jeb->used_size += totlen;
1315 raw->flash_offset = ref_offset(raw)
1316 | ((xd->node == (void *)raw) ? REF_PRISTINE : REF_NORMAL);
1317 }
1318 if (xd->flags & JFFS2_XFLAGS_DEAD)
1319 list_add(new: &xd->xindex, head: &c->xattr_dead_list);
1320 spin_unlock(lock: &c->erase_completion_lock);
1321 }
1322 up_write(sem: &c->xattr_sem);
1323 return list_empty(head: &c->xattr_unchecked) ? 1 : 0;
1324}
1325
1326void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
1327{
1328 /* must be called under spin_lock(&c->erase_completion_lock) */
1329 if (atomic_read(v: &xd->refcnt) || xd->node != (void *)xd)
1330 return;
1331
1332 list_del(entry: &xd->xindex);
1333 jffs2_free_xattr_datum(xd);
1334}
1335
1336void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
1337{
1338 /* must be called under spin_lock(&c->erase_completion_lock) */
1339 struct jffs2_xattr_ref *tmp, **ptmp;
1340
1341 if (ref->node != (void *)ref)
1342 return;
1343
1344 for (tmp=c->xref_dead_list, ptmp=&c->xref_dead_list; tmp; ptmp=&tmp->next, tmp=tmp->next) {
1345 if (ref == tmp) {
1346 *ptmp = tmp->next;
1347 break;
1348 }
1349 }
1350 jffs2_free_xattr_ref(ref);
1351}
1352

source code of linux/fs/jffs2/xattr.c