Merge master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6
[linux-2.6] / fs / jffs2 / xattr.c
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright (C) 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 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/fs.h>
14 #include <linux/time.h>
15 #include <linux/pagemap.h>
16 #include <linux/highmem.h>
17 #include <linux/crc32.h>
18 #include <linux/jffs2.h>
19 #include <linux/xattr.h>
20 #include <linux/mtd/mtd.h>
21 #include "nodelist.h"
22 /* -------- xdatum related functions ----------------
23  * xattr_datum_hashkey(xprefix, xname, xvalue, xsize)
24  *   is used to calcurate xdatum hashkey. The reminder of hashkey into XATTRINDEX_HASHSIZE is
25  *   the index of the xattr name/value pair cache (c->xattrindex).
26  * is_xattr_datum_unchecked(c, xd)
27  *   returns 1, if xdatum contains any unchecked raw nodes. if all raw nodes are not
28  *   unchecked, it returns 0.
29  * unload_xattr_datum(c, xd)
30  *   is used to release xattr name/value pair and detach from c->xattrindex.
31  * reclaim_xattr_datum(c)
32  *   is used to reclaim xattr name/value pairs on the xattr name/value pair cache when
33  *   memory usage by cache is over c->xdatum_mem_threshold. Currentry, this threshold 
34  *   is hard coded as 32KiB.
35  * do_verify_xattr_datum(c, xd)
36  *   is used to load the xdatum informations without name/value pair from the medium.
37  *   It's necessary once, because those informations are not collected during mounting
38  *   process when EBS is enabled.
39  *   0 will be returned, if success. An negative return value means recoverable error, and
40  *   positive return value means unrecoverable error. Thus, caller must remove this xdatum
41  *   and xref when it returned positive value.
42  * do_load_xattr_datum(c, xd)
43  *   is used to load name/value pair from the medium.
44  *   The meanings of return value is same as do_verify_xattr_datum().
45  * load_xattr_datum(c, xd)
46  *   is used to be as a wrapper of do_verify_xattr_datum() and do_load_xattr_datum().
47  *   If xd need to call do_verify_xattr_datum() at first, it's called before calling
48  *   do_load_xattr_datum(). The meanings of return value is same as do_verify_xattr_datum().
49  * save_xattr_datum(c, xd)
50  *   is used to write xdatum to medium. xd->version will be incremented.
51  * create_xattr_datum(c, xprefix, xname, xvalue, xsize)
52  *   is used to create new xdatum and write to medium.
53  * delete_xattr_datum(c, xd)
54  *   is used to delete a xdatum. It marks xd JFFS2_XFLAGS_DEAD, and allows
55  *   GC to reclaim those physical nodes.
56  * -------------------------------------------------- */
57 static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
58 {
59         int name_len = strlen(xname);
60
61         return crc32(xprefix, xname, name_len) ^ crc32(xprefix, xvalue, xsize);
62 }
63
64 static int is_xattr_datum_unchecked(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
65 {
66         struct jffs2_raw_node_ref *raw;
67         int rc = 0;
68
69         spin_lock(&c->erase_completion_lock);
70         for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
71                 if (ref_flags(raw) == REF_UNCHECKED) {
72                         rc = 1;
73                         break;
74                 }
75         }
76         spin_unlock(&c->erase_completion_lock);
77         return rc;
78 }
79
80 static void unload_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
81 {
82         /* must be called under down_write(xattr_sem) */
83         D1(dbg_xattr("%s: xid=%u, version=%u\n", __FUNCTION__, xd->xid, xd->version));
84         if (xd->xname) {
85                 c->xdatum_mem_usage -= (xd->name_len + 1 + xd->value_len);
86                 kfree(xd->xname);
87         }
88
89         list_del_init(&xd->xindex);
90         xd->hashkey = 0;
91         xd->xname = NULL;
92         xd->xvalue = NULL;
93 }
94
95 static void reclaim_xattr_datum(struct jffs2_sb_info *c)
96 {
97         /* must be called under down_write(xattr_sem) */
98         struct jffs2_xattr_datum *xd, *_xd;
99         uint32_t target, before;
100         static int index = 0;
101         int count;
102
103         if (c->xdatum_mem_threshold > c->xdatum_mem_usage)
104                 return;
105
106         before = c->xdatum_mem_usage;
107         target = c->xdatum_mem_usage * 4 / 5; /* 20% reduction */
108         for (count = 0; count < XATTRINDEX_HASHSIZE; count++) {
109                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[index], xindex) {
110                         if (xd->flags & JFFS2_XFLAGS_HOT) {
111                                 xd->flags &= ~JFFS2_XFLAGS_HOT;
112                         } else if (!(xd->flags & JFFS2_XFLAGS_BIND)) {
113                                 unload_xattr_datum(c, xd);
114                         }
115                         if (c->xdatum_mem_usage <= target)
116                                 goto out;
117                 }
118                 index = (index+1) % XATTRINDEX_HASHSIZE;
119         }
120  out:
121         JFFS2_NOTICE("xdatum_mem_usage from %u byte to %u byte (%u byte reclaimed)\n",
122                      before, c->xdatum_mem_usage, before - c->xdatum_mem_usage);
123 }
124
125 static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
126 {
127         /* must be called under down_write(xattr_sem) */
128         struct jffs2_eraseblock *jeb;
129         struct jffs2_raw_node_ref *raw;
130         struct jffs2_raw_xattr rx;
131         size_t readlen;
132         uint32_t crc, offset, totlen;
133         int rc;
134
135         spin_lock(&c->erase_completion_lock);
136         offset = ref_offset(xd->node);
137         if (ref_flags(xd->node) == REF_PRISTINE)
138                 goto complete;
139         spin_unlock(&c->erase_completion_lock);
140
141         rc = jffs2_flash_read(c, offset, sizeof(rx), &readlen, (char *)&rx);
142         if (rc || readlen != sizeof(rx)) {
143                 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
144                               rc, sizeof(rx), readlen, offset);
145                 return rc ? rc : -EIO;
146         }
147         crc = crc32(0, &rx, sizeof(rx) - 4);
148         if (crc != je32_to_cpu(rx.node_crc)) {
149                 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
150                             offset, je32_to_cpu(rx.hdr_crc), crc);
151                 xd->flags |= JFFS2_XFLAGS_INVALID;
152                 return EIO;
153         }
154         totlen = PAD(sizeof(rx) + rx.name_len + 1 + je16_to_cpu(rx.value_len));
155         if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
156             || je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
157             || je32_to_cpu(rx.totlen) != totlen
158             || je32_to_cpu(rx.xid) != xd->xid
159             || je32_to_cpu(rx.version) != xd->version) {
160                 JFFS2_ERROR("inconsistent xdatum at %#08x, magic=%#04x/%#04x, "
161                             "nodetype=%#04x/%#04x, totlen=%u/%u, xid=%u/%u, version=%u/%u\n",
162                             offset, 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                 xd->flags |= JFFS2_XFLAGS_INVALID;
168                 return EIO;
169         }
170         xd->xprefix = rx.xprefix;
171         xd->name_len = rx.name_len;
172         xd->value_len = je16_to_cpu(rx.value_len);
173         xd->data_crc = je32_to_cpu(rx.data_crc);
174
175         spin_lock(&c->erase_completion_lock);
176  complete:
177         for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
178                 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
179                 totlen = PAD(ref_totlen(c, jeb, raw));
180                 if (ref_flags(raw) == REF_UNCHECKED) {
181                         c->unchecked_size -= totlen; c->used_size += totlen;
182                         jeb->unchecked_size -= totlen; jeb->used_size += totlen;
183                 }
184                 raw->flash_offset = ref_offset(raw) | ((xd->node==raw) ? REF_PRISTINE : REF_NORMAL);
185         }
186         spin_unlock(&c->erase_completion_lock);
187
188         /* unchecked xdatum is chained with c->xattr_unchecked */
189         list_del_init(&xd->xindex);
190
191         dbg_xattr("success on verfying xdatum (xid=%u, version=%u)\n",
192                   xd->xid, xd->version);
193
194         return 0;
195 }
196
197 static int do_load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
198 {
199         /* must be called under down_write(xattr_sem) */
200         char *data;
201         size_t readlen;
202         uint32_t crc, length;
203         int i, ret, retry = 0;
204
205         BUG_ON(ref_flags(xd->node) != REF_PRISTINE);
206         BUG_ON(!list_empty(&xd->xindex));
207  retry:
208         length = xd->name_len + 1 + xd->value_len;
209         data = kmalloc(length, GFP_KERNEL);
210         if (!data)
211                 return -ENOMEM;
212
213         ret = jffs2_flash_read(c, ref_offset(xd->node)+sizeof(struct jffs2_raw_xattr),
214                                length, &readlen, data);
215
216         if (ret || length!=readlen) {
217                 JFFS2_WARNING("jffs2_flash_read() returned %d, request=%d, readlen=%zu, at %#08x\n",
218                               ret, length, readlen, ref_offset(xd->node));
219                 kfree(data);
220                 return ret ? ret : -EIO;
221         }
222
223         data[xd->name_len] = '\0';
224         crc = crc32(0, data, length);
225         if (crc != xd->data_crc) {
226                 JFFS2_WARNING("node CRC failed (JFFS2_NODETYPE_XREF)"
227                               " at %#08x, read: 0x%08x calculated: 0x%08x\n",
228                               ref_offset(xd->node), xd->data_crc, crc);
229                 kfree(data);
230                 xd->flags |= JFFS2_XFLAGS_INVALID;
231                 return EIO;
232         }
233
234         xd->flags |= JFFS2_XFLAGS_HOT;
235         xd->xname = data;
236         xd->xvalue = data + xd->name_len+1;
237
238         c->xdatum_mem_usage += length;
239
240         xd->hashkey = xattr_datum_hashkey(xd->xprefix, xd->xname, xd->xvalue, xd->value_len);
241         i = xd->hashkey % XATTRINDEX_HASHSIZE;
242         list_add(&xd->xindex, &c->xattrindex[i]);
243         if (!retry) {
244                 retry = 1;
245                 reclaim_xattr_datum(c);
246                 if (!xd->xname)
247                         goto retry;
248         }
249
250         dbg_xattr("success on loading xdatum (xid=%u, xprefix=%u, xname='%s')\n",
251                   xd->xid, xd->xprefix, xd->xname);
252
253         return 0;
254 }
255
256 static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
257 {
258         /* must be called under down_write(xattr_sem);
259          * rc < 0 : recoverable error, try again
260          * rc = 0 : success
261          * rc > 0 : Unrecoverable error, this node should be deleted.
262          */
263         int rc = 0;
264
265         BUG_ON(xd->flags & JFFS2_XFLAGS_DEAD);
266         if (xd->xname)
267                 return 0;
268         if (xd->flags & JFFS2_XFLAGS_INVALID)
269                 return EIO;
270         if (unlikely(is_xattr_datum_unchecked(c, xd)))
271                 rc = do_verify_xattr_datum(c, xd);
272         if (!rc)
273                 rc = do_load_xattr_datum(c, xd);
274         return rc;
275 }
276
277 static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
278 {
279         /* must be called under down_write(xattr_sem) */
280         struct jffs2_raw_xattr rx;
281         struct kvec vecs[2];
282         size_t length;
283         int rc, totlen;
284         uint32_t phys_ofs = write_ofs(c);
285
286         BUG_ON(!xd->xname);
287         BUG_ON(xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID));
288
289         vecs[0].iov_base = &rx;
290         vecs[0].iov_len = sizeof(rx);
291         vecs[1].iov_base = xd->xname;
292         vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
293         totlen = vecs[0].iov_len + vecs[1].iov_len;
294
295         /* Setup raw-xattr */
296         memset(&rx, 0, sizeof(rx));
297         rx.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
298         rx.nodetype = cpu_to_je16(JFFS2_NODETYPE_XATTR);
299         rx.totlen = cpu_to_je32(PAD(totlen));
300         rx.hdr_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_unknown_node) - 4));
301
302         rx.xid = cpu_to_je32(xd->xid);
303         rx.version = cpu_to_je32(++xd->version);
304         rx.xprefix = xd->xprefix;
305         rx.name_len = xd->name_len;
306         rx.value_len = cpu_to_je16(xd->value_len);
307         rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
308         rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
309
310         rc = jffs2_flash_writev(c, vecs, 2, phys_ofs, &length, 0);
311         if (rc || totlen != length) {
312                 JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%zu, at %#08x\n",
313                               rc, totlen, length, phys_ofs);
314                 rc = rc ? rc : -EIO;
315                 if (length)
316                         jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(totlen), NULL);
317
318                 return rc;
319         }
320         /* success */
321         jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(totlen), (void *)xd);
322
323         dbg_xattr("success on saving xdatum (xid=%u, version=%u, xprefix=%u, xname='%s')\n",
324                   xd->xid, xd->version, xd->xprefix, xd->xname);
325
326         return 0;
327 }
328
329 static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
330                                                     int xprefix, const char *xname,
331                                                     const char *xvalue, int xsize)
332 {
333         /* must be called under down_write(xattr_sem) */
334         struct jffs2_xattr_datum *xd;
335         uint32_t hashkey, name_len;
336         char *data;
337         int i, rc;
338
339         /* Search xattr_datum has same xname/xvalue by index */
340         hashkey = xattr_datum_hashkey(xprefix, xname, xvalue, xsize);
341         i = hashkey % XATTRINDEX_HASHSIZE;
342         list_for_each_entry(xd, &c->xattrindex[i], xindex) {
343                 if (xd->hashkey==hashkey
344                     && xd->xprefix==xprefix
345                     && xd->value_len==xsize
346                     && !strcmp(xd->xname, xname)
347                     && !memcmp(xd->xvalue, xvalue, xsize)) {
348                         atomic_inc(&xd->refcnt);
349                         return xd;
350                 }
351         }
352
353         /* Not found, Create NEW XATTR-Cache */
354         name_len = strlen(xname);
355
356         xd = jffs2_alloc_xattr_datum();
357         if (!xd)
358                 return ERR_PTR(-ENOMEM);
359
360         data = kmalloc(name_len + 1 + xsize, GFP_KERNEL);
361         if (!data) {
362                 jffs2_free_xattr_datum(xd);
363                 return ERR_PTR(-ENOMEM);
364         }
365         strcpy(data, xname);
366         memcpy(data + name_len + 1, xvalue, xsize);
367
368         atomic_set(&xd->refcnt, 1);
369         xd->xid = ++c->highest_xid;
370         xd->flags |= JFFS2_XFLAGS_HOT;
371         xd->xprefix = xprefix;
372
373         xd->hashkey = hashkey;
374         xd->xname = data;
375         xd->xvalue = data + name_len + 1;
376         xd->name_len = name_len;
377         xd->value_len = xsize;
378         xd->data_crc = crc32(0, data, xd->name_len + 1 + xd->value_len);
379
380         rc = save_xattr_datum(c, xd);
381         if (rc) {
382                 kfree(xd->xname);
383                 jffs2_free_xattr_datum(xd);
384                 return ERR_PTR(rc);
385         }
386
387         /* Insert Hash Index */
388         i = hashkey % XATTRINDEX_HASHSIZE;
389         list_add(&xd->xindex, &c->xattrindex[i]);
390
391         c->xdatum_mem_usage += (xd->name_len + 1 + xd->value_len);
392         reclaim_xattr_datum(c);
393
394         return xd;
395 }
396
397 static void delete_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
398 {
399         /* must be called under down_write(xattr_sem) */
400         BUG_ON(atomic_read(&xd->refcnt));
401
402         unload_xattr_datum(c, xd);
403         xd->flags |= JFFS2_XFLAGS_DEAD;
404         spin_lock(&c->erase_completion_lock);
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         dbg_xattr("xdatum(xid=%u, version=%u) was removed.\n", xd->xid, xd->version);
413 }
414
415 /* -------- xref related functions ------------------
416  * verify_xattr_ref(c, ref)
417  *   is used to load xref information from medium. Because summary data does not
418  *   contain xid/ino, it's necessary to verify once while mounting process.
419  * save_xattr_ref(c, ref)
420  *   is used to write xref to medium. If delete marker is marked, it write
421  *   a delete marker of xref into medium.
422  * create_xattr_ref(c, ic, xd)
423  *   is used to create a new xref and write to medium.
424  * delete_xattr_ref(c, ref)
425  *   is used to delete jffs2_xattr_ref. It marks xref XREF_DELETE_MARKER,
426  *   and allows GC to reclaim those physical nodes.
427  * jffs2_xattr_delete_inode(c, ic)
428  *   is called to remove xrefs related to obsolete inode when inode is unlinked.
429  * jffs2_xattr_free_inode(c, ic)
430  *   is called to release xattr related objects when unmounting. 
431  * check_xattr_ref_inode(c, ic)
432  *   is used to confirm inode does not have duplicate xattr name/value pair.
433  * -------------------------------------------------- */
434 static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
435 {
436         struct jffs2_eraseblock *jeb;
437         struct jffs2_raw_node_ref *raw;
438         struct jffs2_raw_xref rr;
439         size_t readlen;
440         uint32_t crc, offset, totlen;
441         int rc;
442
443         spin_lock(&c->erase_completion_lock);
444         if (ref_flags(ref->node) != REF_UNCHECKED)
445                 goto complete;
446         offset = ref_offset(ref->node);
447         spin_unlock(&c->erase_completion_lock);
448
449         rc = jffs2_flash_read(c, offset, sizeof(rr), &readlen, (char *)&rr);
450         if (rc || sizeof(rr) != readlen) {
451                 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu, at %#08x\n",
452                               rc, sizeof(rr), readlen, offset);
453                 return rc ? rc : -EIO;
454         }
455         /* obsolete node */
456         crc = crc32(0, &rr, sizeof(rr) - 4);
457         if (crc != je32_to_cpu(rr.node_crc)) {
458                 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
459                             offset, je32_to_cpu(rr.node_crc), crc);
460                 return EIO;
461         }
462         if (je16_to_cpu(rr.magic) != JFFS2_MAGIC_BITMASK
463             || je16_to_cpu(rr.nodetype) != JFFS2_NODETYPE_XREF
464             || je32_to_cpu(rr.totlen) != PAD(sizeof(rr))) {
465                 JFFS2_ERROR("inconsistent xref at %#08x, magic=%#04x/%#04x, "
466                             "nodetype=%#04x/%#04x, totlen=%u/%zu\n",
467                             offset, je16_to_cpu(rr.magic), JFFS2_MAGIC_BITMASK,
468                             je16_to_cpu(rr.nodetype), JFFS2_NODETYPE_XREF,
469                             je32_to_cpu(rr.totlen), PAD(sizeof(rr)));
470                 return EIO;
471         }
472         ref->ino = je32_to_cpu(rr.ino);
473         ref->xid = je32_to_cpu(rr.xid);
474         ref->xseqno = je32_to_cpu(rr.xseqno);
475         if (ref->xseqno > c->highest_xseqno)
476                 c->highest_xseqno = (ref->xseqno & ~XREF_DELETE_MARKER);
477
478         spin_lock(&c->erase_completion_lock);
479  complete:
480         for (raw=ref->node; raw != (void *)ref; raw=raw->next_in_ino) {
481                 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
482                 totlen = PAD(ref_totlen(c, jeb, raw));
483                 if (ref_flags(raw) == REF_UNCHECKED) {
484                         c->unchecked_size -= totlen; c->used_size += totlen;
485                         jeb->unchecked_size -= totlen; jeb->used_size += totlen;
486                 }
487                 raw->flash_offset = ref_offset(raw) | ((ref->node==raw) ? REF_PRISTINE : REF_NORMAL);
488         }
489         spin_unlock(&c->erase_completion_lock);
490
491         dbg_xattr("success on verifying xref (ino=%u, xid=%u) at %#08x\n",
492                   ref->ino, ref->xid, ref_offset(ref->node));
493         return 0;
494 }
495
496 static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
497 {
498         /* must be called under down_write(xattr_sem) */
499         struct jffs2_raw_xref rr;
500         size_t length;
501         uint32_t xseqno, phys_ofs = write_ofs(c);
502         int ret;
503
504         rr.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
505         rr.nodetype = cpu_to_je16(JFFS2_NODETYPE_XREF);
506         rr.totlen = cpu_to_je32(PAD(sizeof(rr)));
507         rr.hdr_crc = cpu_to_je32(crc32(0, &rr, sizeof(struct jffs2_unknown_node) - 4));
508
509         xseqno = (c->highest_xseqno += 2);
510         if (is_xattr_ref_dead(ref)) {
511                 xseqno |= XREF_DELETE_MARKER;
512                 rr.ino = cpu_to_je32(ref->ino);
513                 rr.xid = cpu_to_je32(ref->xid);
514         } else {
515                 rr.ino = cpu_to_je32(ref->ic->ino);
516                 rr.xid = cpu_to_je32(ref->xd->xid);
517         }
518         rr.xseqno = cpu_to_je32(xseqno);
519         rr.node_crc = cpu_to_je32(crc32(0, &rr, sizeof(rr) - 4));
520
521         ret = jffs2_flash_write(c, phys_ofs, sizeof(rr), &length, (char *)&rr);
522         if (ret || sizeof(rr) != length) {
523                 JFFS2_WARNING("jffs2_flash_write() returned %d, request=%zu, retlen=%zu, at %#08x\n",
524                               ret, sizeof(rr), length, phys_ofs);
525                 ret = ret ? ret : -EIO;
526                 if (length)
527                         jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(sizeof(rr)), NULL);
528
529                 return ret;
530         }
531         /* success */
532         ref->xseqno = xseqno;
533         jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), (void *)ref);
534
535         dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid);
536
537         return 0;
538 }
539
540 static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic,
541                                                 struct jffs2_xattr_datum *xd)
542 {
543         /* must be called under down_write(xattr_sem) */
544         struct jffs2_xattr_ref *ref;
545         int ret;
546
547         ref = jffs2_alloc_xattr_ref();
548         if (!ref)
549                 return ERR_PTR(-ENOMEM);
550         ref->ic = ic;
551         ref->xd = xd;
552
553         ret = save_xattr_ref(c, ref);
554         if (ret) {
555                 jffs2_free_xattr_ref(ref);
556                 return ERR_PTR(ret);
557         }
558
559         /* Chain to inode */
560         ref->next = ic->xref;
561         ic->xref = ref;
562
563         return ref; /* success */
564 }
565
566 static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
567 {
568         /* must be called under down_write(xattr_sem) */
569         struct jffs2_xattr_datum *xd;
570
571         xd = ref->xd;
572         ref->xseqno |= XREF_DELETE_MARKER;
573         ref->ino = ref->ic->ino;
574         ref->xid = ref->xd->xid;
575         spin_lock(&c->erase_completion_lock);
576         ref->next = c->xref_dead_list;
577         c->xref_dead_list = ref;
578         spin_unlock(&c->erase_completion_lock);
579
580         dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) was removed.\n",
581                   ref->ino, ref->xid, ref->xseqno);
582
583         if (atomic_dec_and_test(&xd->refcnt))
584                 delete_xattr_datum(c, xd);
585 }
586
587 void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
588 {
589         /* It's called from jffs2_clear_inode() on inode removing.
590            When an inode with XATTR is removed, those XATTRs must be removed. */
591         struct jffs2_xattr_ref *ref, *_ref;
592
593         if (!ic || ic->nlink > 0)
594                 return;
595
596         down_write(&c->xattr_sem);
597         for (ref = ic->xref; ref; ref = _ref) {
598                 _ref = ref->next;
599                 delete_xattr_ref(c, ref);
600         }
601         ic->xref = NULL;
602         up_write(&c->xattr_sem);
603 }
604
605 void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
606 {
607         /* It's called from jffs2_free_ino_caches() until unmounting FS. */
608         struct jffs2_xattr_datum *xd;
609         struct jffs2_xattr_ref *ref, *_ref;
610
611         down_write(&c->xattr_sem);
612         for (ref = ic->xref; ref; ref = _ref) {
613                 _ref = ref->next;
614                 xd = ref->xd;
615                 if (atomic_dec_and_test(&xd->refcnt)) {
616                         unload_xattr_datum(c, xd);
617                         jffs2_free_xattr_datum(xd);
618                 }
619                 jffs2_free_xattr_ref(ref);
620         }
621         ic->xref = NULL;
622         up_write(&c->xattr_sem);
623 }
624
625 static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
626 {
627         /* success of check_xattr_ref_inode() means taht inode (ic) dose not have
628          * duplicate name/value pairs. If duplicate name/value pair would be found,
629          * one will be removed.
630          */
631         struct jffs2_xattr_ref *ref, *cmp, **pref, **pcmp;
632         int rc = 0;
633
634         if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
635                 return 0;
636         down_write(&c->xattr_sem);
637  retry:
638         rc = 0;
639         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
640                 if (!ref->xd->xname) {
641                         rc = load_xattr_datum(c, ref->xd);
642                         if (unlikely(rc > 0)) {
643                                 *pref = ref->next;
644                                 delete_xattr_ref(c, ref);
645                                 goto retry;
646                         } else if (unlikely(rc < 0))
647                                 goto out;
648                 }
649                 for (cmp=ref->next, pcmp=&ref->next; cmp; pcmp=&cmp->next, cmp=cmp->next) {
650                         if (!cmp->xd->xname) {
651                                 ref->xd->flags |= JFFS2_XFLAGS_BIND;
652                                 rc = load_xattr_datum(c, cmp->xd);
653                                 ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
654                                 if (unlikely(rc > 0)) {
655                                         *pcmp = cmp->next;
656                                         delete_xattr_ref(c, cmp);
657                                         goto retry;
658                                 } else if (unlikely(rc < 0))
659                                         goto out;
660                         }
661                         if (ref->xd->xprefix == cmp->xd->xprefix
662                             && !strcmp(ref->xd->xname, cmp->xd->xname)) {
663                                 if (ref->xseqno > cmp->xseqno) {
664                                         *pcmp = cmp->next;
665                                         delete_xattr_ref(c, cmp);
666                                 } else {
667                                         *pref = ref->next;
668                                         delete_xattr_ref(c, ref);
669                                 }
670                                 goto retry;
671                         }
672                 }
673         }
674         ic->flags |= INO_FLAGS_XATTR_CHECKED;
675  out:
676         up_write(&c->xattr_sem);
677
678         return rc;
679 }
680
681 /* -------- xattr subsystem functions ---------------
682  * jffs2_init_xattr_subsystem(c)
683  *   is used to initialize semaphore and list_head, and some variables.
684  * jffs2_find_xattr_datum(c, xid)
685  *   is used to lookup xdatum while scanning process.
686  * jffs2_clear_xattr_subsystem(c)
687  *   is used to release any xattr related objects.
688  * jffs2_build_xattr_subsystem(c)
689  *   is used to associate xdatum and xref while super block building process.
690  * jffs2_setup_xattr_datum(c, xid, version)
691  *   is used to insert xdatum while scanning process.
692  * -------------------------------------------------- */
693 void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
694 {
695         int i;
696
697         for (i=0; i < XATTRINDEX_HASHSIZE; i++)
698                 INIT_LIST_HEAD(&c->xattrindex[i]);
699         INIT_LIST_HEAD(&c->xattr_unchecked);
700         INIT_LIST_HEAD(&c->xattr_dead_list);
701         c->xref_dead_list = NULL;
702         c->xref_temp = NULL;
703
704         init_rwsem(&c->xattr_sem);
705         c->highest_xid = 0;
706         c->highest_xseqno = 0;
707         c->xdatum_mem_usage = 0;
708         c->xdatum_mem_threshold = 32 * 1024;    /* Default 32KB */
709 }
710
711 static struct jffs2_xattr_datum *jffs2_find_xattr_datum(struct jffs2_sb_info *c, uint32_t xid)
712 {
713         struct jffs2_xattr_datum *xd;
714         int i = xid % XATTRINDEX_HASHSIZE;
715
716         /* It's only used in scanning/building process. */
717         BUG_ON(!(c->flags & (JFFS2_SB_FLAG_SCANNING|JFFS2_SB_FLAG_BUILDING)));
718
719         list_for_each_entry(xd, &c->xattrindex[i], xindex) {
720                 if (xd->xid==xid)
721                         return xd;
722         }
723         return NULL;
724 }
725
726 void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
727 {
728         struct jffs2_xattr_datum *xd, *_xd;
729         struct jffs2_xattr_ref *ref, *_ref;
730         int i;
731
732         for (ref=c->xref_temp; ref; ref = _ref) {
733                 _ref = ref->next;
734                 jffs2_free_xattr_ref(ref);
735         }
736
737         for (ref=c->xref_dead_list; ref; ref = _ref) {
738                 _ref = ref->next;
739                 jffs2_free_xattr_ref(ref);
740         }
741
742         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
743                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
744                         list_del(&xd->xindex);
745                         if (xd->xname)
746                                 kfree(xd->xname);
747                         jffs2_free_xattr_datum(xd);
748                 }
749         }
750
751         list_for_each_entry_safe(xd, _xd, &c->xattr_dead_list, xindex) {
752                 list_del(&xd->xindex);
753                 jffs2_free_xattr_datum(xd);
754         }
755 }
756
757 #define XREF_TMPHASH_SIZE       (128)
758 void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
759 {
760         struct jffs2_xattr_ref *ref, *_ref;
761         struct jffs2_xattr_ref *xref_tmphash[XREF_TMPHASH_SIZE];
762         struct jffs2_xattr_datum *xd, *_xd;
763         struct jffs2_inode_cache *ic;
764         struct jffs2_raw_node_ref *raw;
765         int i, xdatum_count = 0, xdatum_unchecked_count = 0, xref_count = 0;
766         int xdatum_orphan_count = 0, xref_orphan_count = 0, xref_dead_count = 0;
767
768         BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
769
770         /* Phase.1 : Merge same xref */
771         for (i=0; i < XREF_TMPHASH_SIZE; i++)
772                 xref_tmphash[i] = NULL;
773         for (ref=c->xref_temp; ref; ref=_ref) {
774                 struct jffs2_xattr_ref *tmp;
775
776                 _ref = ref->next;
777                 if (ref_flags(ref->node) != REF_PRISTINE) {
778                         if (verify_xattr_ref(c, ref)) {
779                                 BUG_ON(ref->node->next_in_ino != (void *)ref);
780                                 ref->node->next_in_ino = NULL;
781                                 jffs2_mark_node_obsolete(c, ref->node);
782                                 jffs2_free_xattr_ref(ref);
783                                 continue;
784                         }
785                 }
786
787                 i = (ref->ino ^ ref->xid) % XREF_TMPHASH_SIZE;
788                 for (tmp=xref_tmphash[i]; tmp; tmp=tmp->next) {
789                         if (tmp->ino == ref->ino && tmp->xid == ref->xid)
790                                 break;
791                 }
792                 if (tmp) {
793                         raw = ref->node;
794                         if (ref->xseqno > tmp->xseqno) {
795                                 tmp->xseqno = ref->xseqno;
796                                 raw->next_in_ino = tmp->node;
797                                 tmp->node = raw;
798                         } else {
799                                 raw->next_in_ino = tmp->node->next_in_ino;
800                                 tmp->node->next_in_ino = raw;
801                         }
802                         jffs2_free_xattr_ref(ref);
803                         continue;
804                 } else {
805                         ref->next = xref_tmphash[i];
806                         xref_tmphash[i] = ref;
807                 }
808         }
809         c->xref_temp = NULL;
810
811         /* Phase.2 : Bind xref with inode_cache and xattr_datum */
812         for (i=0; i < XREF_TMPHASH_SIZE; i++) {
813                 for (ref=xref_tmphash[i]; ref; ref=_ref) {
814                         xref_count++;
815                         _ref = ref->next;
816                         if (is_xattr_ref_dead(ref)) {
817                                 ref->next = c->xref_dead_list;
818                                 c->xref_dead_list = ref;
819                                 xref_dead_count++;
820                                 continue;
821                         }
822                         /* At this point, ref->xid and ref->ino contain XID and inode number.
823                            ref->xd and ref->ic are not valid yet. */
824                         xd = jffs2_find_xattr_datum(c, ref->xid);
825                         ic = jffs2_get_ino_cache(c, ref->ino);
826                         if (!xd || !ic) {
827                                 dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) is orphan.\n",
828                                           ref->ino, ref->xid, ref->xseqno);
829                                 ref->xseqno |= XREF_DELETE_MARKER;
830                                 ref->next = c->xref_dead_list;
831                                 c->xref_dead_list = ref;
832                                 xref_orphan_count++;
833                                 continue;
834                         }
835                         ref->xd = xd;
836                         ref->ic = ic;
837                         atomic_inc(&xd->refcnt);
838                         ref->next = ic->xref;
839                         ic->xref = ref;
840                 }
841         }
842
843         /* Phase.3 : Link unchecked xdatum to xattr_unchecked list */
844         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
845                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
846                         xdatum_count++;
847                         list_del_init(&xd->xindex);
848                         if (!atomic_read(&xd->refcnt)) {
849                                 dbg_xattr("xdatum(xid=%u, version=%u) is orphan.\n",
850                                           xd->xid, xd->version);
851                                 xd->flags |= JFFS2_XFLAGS_DEAD;
852                                 list_add(&xd->xindex, &c->xattr_unchecked);
853                                 xdatum_orphan_count++;
854                                 continue;
855                         }
856                         if (is_xattr_datum_unchecked(c, xd)) {
857                                 dbg_xattr("unchecked xdatum(xid=%u, version=%u)\n",
858                                           xd->xid, xd->version);
859                                 list_add(&xd->xindex, &c->xattr_unchecked);
860                                 xdatum_unchecked_count++;
861                         }
862                 }
863         }
864         /* build complete */
865         JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum"
866                      " (%u unchecked, %u orphan) and "
867                      "%u of xref (%u dead, %u orphan) found.\n",
868                      xdatum_count, xdatum_unchecked_count, xdatum_orphan_count,
869                      xref_count, xref_dead_count, xref_orphan_count);
870 }
871
872 struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
873                                                   uint32_t xid, uint32_t version)
874 {
875         struct jffs2_xattr_datum *xd;
876
877         xd = jffs2_find_xattr_datum(c, xid);
878         if (!xd) {
879                 xd = jffs2_alloc_xattr_datum();
880                 if (!xd)
881                         return ERR_PTR(-ENOMEM);
882                 xd->xid = xid;
883                 xd->version = version;
884                 if (xd->xid > c->highest_xid)
885                         c->highest_xid = xd->xid;
886                 list_add_tail(&xd->xindex, &c->xattrindex[xid % XATTRINDEX_HASHSIZE]);
887         }
888         return xd;
889 }
890
891 /* -------- xattr subsystem functions ---------------
892  * xprefix_to_handler(xprefix)
893  *   is used to translate xprefix into xattr_handler.
894  * jffs2_listxattr(dentry, buffer, size)
895  *   is an implementation of listxattr handler on jffs2.
896  * do_jffs2_getxattr(inode, xprefix, xname, buffer, size)
897  *   is an implementation of getxattr handler on jffs2.
898  * do_jffs2_setxattr(inode, xprefix, xname, buffer, size, flags)
899  *   is an implementation of setxattr handler on jffs2.
900  * -------------------------------------------------- */
901 struct xattr_handler *jffs2_xattr_handlers[] = {
902         &jffs2_user_xattr_handler,
903 #ifdef CONFIG_JFFS2_FS_SECURITY
904         &jffs2_security_xattr_handler,
905 #endif
906 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
907         &jffs2_acl_access_xattr_handler,
908         &jffs2_acl_default_xattr_handler,
909 #endif
910         &jffs2_trusted_xattr_handler,
911         NULL
912 };
913
914 static struct xattr_handler *xprefix_to_handler(int xprefix) {
915         struct xattr_handler *ret;
916
917         switch (xprefix) {
918         case JFFS2_XPREFIX_USER:
919                 ret = &jffs2_user_xattr_handler;
920                 break;
921 #ifdef CONFIG_JFFS2_FS_SECURITY
922         case JFFS2_XPREFIX_SECURITY:
923                 ret = &jffs2_security_xattr_handler;
924                 break;
925 #endif
926 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
927         case JFFS2_XPREFIX_ACL_ACCESS:
928                 ret = &jffs2_acl_access_xattr_handler;
929                 break;
930         case JFFS2_XPREFIX_ACL_DEFAULT:
931                 ret = &jffs2_acl_default_xattr_handler;
932                 break;
933 #endif
934         case JFFS2_XPREFIX_TRUSTED:
935                 ret = &jffs2_trusted_xattr_handler;
936                 break;
937         default:
938                 ret = NULL;
939                 break;
940         }
941         return ret;
942 }
943
944 ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
945 {
946         struct inode *inode = dentry->d_inode;
947         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
948         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
949         struct jffs2_inode_cache *ic = f->inocache;
950         struct jffs2_xattr_ref *ref, **pref;
951         struct jffs2_xattr_datum *xd;
952         struct xattr_handler *xhandle;
953         ssize_t len, rc;
954         int retry = 0;
955
956         rc = check_xattr_ref_inode(c, ic);
957         if (unlikely(rc))
958                 return rc;
959
960         down_read(&c->xattr_sem);
961  retry:
962         len = 0;
963         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
964                 BUG_ON(ref->ic != ic);
965                 xd = ref->xd;
966                 if (!xd->xname) {
967                         /* xdatum is unchached */
968                         if (!retry) {
969                                 retry = 1;
970                                 up_read(&c->xattr_sem);
971                                 down_write(&c->xattr_sem);
972                                 goto retry;
973                         } else {
974                                 rc = load_xattr_datum(c, xd);
975                                 if (unlikely(rc > 0)) {
976                                         *pref = ref->next;
977                                         delete_xattr_ref(c, ref);
978                                         goto retry;
979                                 } else if (unlikely(rc < 0))
980                                         goto out;
981                         }
982                 }
983                 xhandle = xprefix_to_handler(xd->xprefix);
984                 if (!xhandle)
985                         continue;
986                 if (buffer) {
987                         rc = xhandle->list(inode, buffer+len, size-len, xd->xname, xd->name_len);
988                 } else {
989                         rc = xhandle->list(inode, NULL, 0, xd->xname, xd->name_len);
990                 }
991                 if (rc < 0)
992                         goto out;
993                 len += rc;
994         }
995         rc = len;
996  out:
997         if (!retry) {
998                 up_read(&c->xattr_sem);
999         } else {
1000                 up_write(&c->xattr_sem);
1001         }
1002         return rc;
1003 }
1004
1005 int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
1006                       char *buffer, size_t size)
1007 {
1008         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1009         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1010         struct jffs2_inode_cache *ic = f->inocache;
1011         struct jffs2_xattr_datum *xd;
1012         struct jffs2_xattr_ref *ref, **pref;
1013         int rc, retry = 0;
1014
1015         rc = check_xattr_ref_inode(c, ic);
1016         if (unlikely(rc))
1017                 return rc;
1018
1019         down_read(&c->xattr_sem);
1020  retry:
1021         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1022                 BUG_ON(ref->ic!=ic);
1023
1024                 xd = ref->xd;
1025                 if (xd->xprefix != xprefix)
1026                         continue;
1027                 if (!xd->xname) {
1028                         /* xdatum is unchached */
1029                         if (!retry) {
1030                                 retry = 1;
1031                                 up_read(&c->xattr_sem);
1032                                 down_write(&c->xattr_sem);
1033                                 goto retry;
1034                         } else {
1035                                 rc = load_xattr_datum(c, xd);
1036                                 if (unlikely(rc > 0)) {
1037                                         *pref = ref->next;
1038                                         delete_xattr_ref(c, ref);
1039                                         goto retry;
1040                                 } else if (unlikely(rc < 0)) {
1041                                         goto out;
1042                                 }
1043                         }
1044                 }
1045                 if (!strcmp(xname, xd->xname)) {
1046                         rc = xd->value_len;
1047                         if (buffer) {
1048                                 if (size < rc) {
1049                                         rc = -ERANGE;
1050                                 } else {
1051                                         memcpy(buffer, xd->xvalue, rc);
1052                                 }
1053                         }
1054                         goto out;
1055                 }
1056         }
1057         rc = -ENODATA;
1058  out:
1059         if (!retry) {
1060                 up_read(&c->xattr_sem);
1061         } else {
1062                 up_write(&c->xattr_sem);
1063         }
1064         return rc;
1065 }
1066
1067 int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
1068                       const char *buffer, size_t size, int flags)
1069 {
1070         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1071         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1072         struct jffs2_inode_cache *ic = f->inocache;
1073         struct jffs2_xattr_datum *xd;
1074         struct jffs2_xattr_ref *ref, *newref, **pref;
1075         uint32_t length, request;
1076         int rc;
1077
1078         rc = check_xattr_ref_inode(c, ic);
1079         if (unlikely(rc))
1080                 return rc;
1081
1082         request = PAD(sizeof(struct jffs2_raw_xattr) + strlen(xname) + 1 + size);
1083         rc = jffs2_reserve_space(c, request, &length,
1084                                  ALLOC_NORMAL, JFFS2_SUMMARY_XATTR_SIZE);
1085         if (rc) {
1086                 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1087                 return rc;
1088         }
1089
1090         /* Find existing xattr */
1091         down_write(&c->xattr_sem);
1092  retry:
1093         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1094                 xd = ref->xd;
1095                 if (xd->xprefix != xprefix)
1096                         continue;
1097                 if (!xd->xname) {
1098                         rc = load_xattr_datum(c, xd);
1099                         if (unlikely(rc > 0)) {
1100                                 *pref = ref->next;
1101                                 delete_xattr_ref(c, ref);
1102                                 goto retry;
1103                         } else if (unlikely(rc < 0))
1104                                 goto out;
1105                 }
1106                 if (!strcmp(xd->xname, xname)) {
1107                         if (flags & XATTR_CREATE) {
1108                                 rc = -EEXIST;
1109                                 goto out;
1110                         }
1111                         if (!buffer) {
1112                                 ref->ino = ic->ino;
1113                                 ref->xid = xd->xid;
1114                                 ref->xseqno |= XREF_DELETE_MARKER;
1115                                 rc = save_xattr_ref(c, ref);
1116                                 if (!rc) {
1117                                         *pref = ref->next;
1118                                         spin_lock(&c->erase_completion_lock);
1119                                         ref->next = c->xref_dead_list;
1120                                         c->xref_dead_list = ref;
1121                                         spin_unlock(&c->erase_completion_lock);
1122                                         if (atomic_dec_and_test(&xd->refcnt))
1123                                                 delete_xattr_datum(c, xd);
1124                                 } else {
1125                                         ref->ic = ic;
1126                                         ref->xd = xd;
1127                                         ref->xseqno &= ~XREF_DELETE_MARKER;
1128                                 }
1129                                 goto out;
1130                         }
1131                         goto found;
1132                 }
1133         }
1134         /* not found */
1135         if (flags & XATTR_REPLACE) {
1136                 rc = -ENODATA;
1137                 goto out;
1138         }
1139         if (!buffer) {
1140                 rc = -ENODATA;
1141                 goto out;
1142         }
1143  found:
1144         xd = create_xattr_datum(c, xprefix, xname, buffer, size);
1145         if (IS_ERR(xd)) {
1146                 rc = PTR_ERR(xd);
1147                 goto out;
1148         }
1149         up_write(&c->xattr_sem);
1150         jffs2_complete_reservation(c);
1151
1152         /* create xattr_ref */
1153         request = PAD(sizeof(struct jffs2_raw_xref));
1154         rc = jffs2_reserve_space(c, request, &length,
1155                                  ALLOC_NORMAL, JFFS2_SUMMARY_XREF_SIZE);
1156         down_write(&c->xattr_sem);
1157         if (rc) {
1158                 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1159                 if (atomic_dec_and_test(&xd->refcnt))
1160                         delete_xattr_datum(c, xd);
1161                 up_write(&c->xattr_sem);
1162                 return rc;
1163         }
1164         if (ref)
1165                 *pref = ref->next;
1166         newref = create_xattr_ref(c, ic, xd);
1167         if (IS_ERR(newref)) {
1168                 if (ref) {
1169                         ref->next = ic->xref;
1170                         ic->xref = ref;
1171                 }
1172                 rc = PTR_ERR(newref);
1173                 if (atomic_dec_and_test(&xd->refcnt))
1174                         delete_xattr_datum(c, xd);
1175         } else if (ref) {
1176                 delete_xattr_ref(c, ref);
1177         }
1178  out:
1179         up_write(&c->xattr_sem);
1180         jffs2_complete_reservation(c);
1181         return rc;
1182 }
1183
1184 /* -------- garbage collector functions -------------
1185  * jffs2_garbage_collect_xattr_datum(c, xd, raw)
1186  *   is used to move xdatum into new node.
1187  * jffs2_garbage_collect_xattr_ref(c, ref, raw)
1188  *   is used to move xref into new node.
1189  * jffs2_verify_xattr(c)
1190  *   is used to call do_verify_xattr_datum() before garbage collecting.
1191  * jffs2_release_xattr_datum(c, xd)
1192  *   is used to release an in-memory object of xdatum.
1193  * jffs2_release_xattr_ref(c, ref)
1194  *   is used to release an in-memory object of xref.
1195  * -------------------------------------------------- */
1196 int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
1197                                       struct jffs2_raw_node_ref *raw)
1198 {
1199         uint32_t totlen, length, old_ofs;
1200         int rc = 0;
1201
1202         down_write(&c->xattr_sem);
1203         if (xd->node != raw)
1204                 goto out;
1205         if (xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID))
1206                 goto out;
1207
1208         rc = load_xattr_datum(c, xd);
1209         if (unlikely(rc)) {
1210                 rc = (rc > 0) ? 0 : rc;
1211                 goto out;
1212         }
1213         old_ofs = ref_offset(xd->node);
1214         totlen = PAD(sizeof(struct jffs2_raw_xattr)
1215                         + xd->name_len + 1 + xd->value_len);
1216         rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XATTR_SIZE);
1217         if (rc) {
1218                 JFFS2_WARNING("jffs2_reserve_space_gc()=%d, request=%u\n", rc, totlen);
1219                 rc = rc ? rc : -EBADFD;
1220                 goto out;
1221         }
1222         rc = save_xattr_datum(c, xd);
1223         if (!rc)
1224                 dbg_xattr("xdatum (xid=%u, version=%u) GC'ed from %#08x to %08x\n",
1225                           xd->xid, xd->version, old_ofs, ref_offset(xd->node));
1226  out:
1227         if (!rc)
1228                 jffs2_mark_node_obsolete(c, raw);
1229         up_write(&c->xattr_sem);
1230         return rc;
1231 }
1232
1233 int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
1234                                     struct jffs2_raw_node_ref *raw)
1235 {
1236         uint32_t totlen, length, old_ofs;
1237         int rc = 0;
1238
1239         down_write(&c->xattr_sem);
1240         BUG_ON(!ref->node);
1241
1242         if (ref->node != raw)
1243                 goto out;
1244         if (is_xattr_ref_dead(ref) && (raw->next_in_ino == (void *)ref))
1245                 goto out;
1246
1247         old_ofs = ref_offset(ref->node);
1248         totlen = ref_totlen(c, c->gcblock, ref->node);
1249
1250         rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XREF_SIZE);
1251         if (rc) {
1252                 JFFS2_WARNING("%s: jffs2_reserve_space_gc() = %d, request = %u\n",
1253                               __FUNCTION__, rc, totlen);
1254                 rc = rc ? rc : -EBADFD;
1255                 goto out;
1256         }
1257         rc = save_xattr_ref(c, ref);
1258         if (!rc)
1259                 dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n",
1260                           ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node));
1261  out:
1262         if (!rc)
1263                 jffs2_mark_node_obsolete(c, raw);
1264         up_write(&c->xattr_sem);
1265         return rc;
1266 }
1267
1268 int jffs2_verify_xattr(struct jffs2_sb_info *c)
1269 {
1270         struct jffs2_xattr_datum *xd, *_xd;
1271         struct jffs2_eraseblock *jeb;
1272         struct jffs2_raw_node_ref *raw;
1273         uint32_t totlen;
1274         int rc;
1275
1276         down_write(&c->xattr_sem);
1277         list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
1278                 rc = do_verify_xattr_datum(c, xd);
1279                 if (rc < 0)
1280                         continue;
1281                 list_del_init(&xd->xindex);
1282                 spin_lock(&c->erase_completion_lock);
1283                 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
1284                         if (ref_flags(raw) != REF_UNCHECKED)
1285                                 continue;
1286                         jeb = &c->blocks[ref_offset(raw) / c->sector_size];
1287                         totlen = PAD(ref_totlen(c, jeb, raw));
1288                         c->unchecked_size -= totlen; c->used_size += totlen;
1289                         jeb->unchecked_size -= totlen; jeb->used_size += totlen;
1290                         raw->flash_offset = ref_offset(raw)
1291                                 | ((xd->node == (void *)raw) ? REF_PRISTINE : REF_NORMAL);
1292                 }
1293                 if (xd->flags & JFFS2_XFLAGS_DEAD)
1294                         list_add(&xd->xindex, &c->xattr_dead_list);
1295                 spin_unlock(&c->erase_completion_lock);
1296         }
1297         up_write(&c->xattr_sem);
1298         return list_empty(&c->xattr_unchecked) ? 1 : 0;
1299 }
1300
1301 void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
1302 {
1303         /* must be called under spin_lock(&c->erase_completion_lock) */
1304         if (atomic_read(&xd->refcnt) || xd->node != (void *)xd)
1305                 return;
1306
1307         list_del(&xd->xindex);
1308         jffs2_free_xattr_datum(xd);
1309 }
1310
1311 void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
1312 {
1313         /* must be called under spin_lock(&c->erase_completion_lock) */
1314         struct jffs2_xattr_ref *tmp, **ptmp;
1315
1316         if (ref->node != (void *)ref)
1317                 return;
1318
1319         for (tmp=c->xref_dead_list, ptmp=&c->xref_dead_list; tmp; ptmp=&tmp->next, tmp=tmp->next) {
1320                 if (ref == tmp) {
1321                         *ptmp = tmp->next;
1322                         break;
1323                 }
1324         }
1325         jffs2_free_xattr_ref(ref);
1326 }