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_delay(c, xd)
  54  *   is used to delete a xdatum without 'delete marker'. It has a possibility to detect
  55  *   orphan xdatum on next mounting.
  56  * delete_xattr_datum(c, xd)
  57  *   is used to delete a xdatum with 'delete marker'. Calling jffs2_reserve_space() is
  58  *   necessary before this function.
  59  * -------------------------------------------------- */
  60 static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
  61 {
  62         int name_len = strlen(xname);
  63
  64         return crc32(xprefix, xname, name_len) ^ crc32(xprefix, xvalue, xsize);
  65 }
  66
  67 static int is_xattr_datum_unchecked(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
  68 {
  69         struct jffs2_raw_node_ref *raw;
  70         int rc = 0;
  71
  72         spin_lock(&c->erase_completion_lock);
  73         for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
  74                 if (ref_flags(raw) == REF_UNCHECKED) {
  75                         rc = 1;
  76                         break;
  77                 }
  78         }
  79         spin_unlock(&c->erase_completion_lock);
  80         return rc;
  81 }
  82
  83 static void unload_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
  84 {
  85         /* must be called under down_write(xattr_sem) */
  86         D1(dbg_xattr("%s: xid=%u, version=%u\n", __FUNCTION__, xd->xid, xd->version));
  87         if (xd->xname) {
  88                 c->xdatum_mem_usage -= (xd->name_len + 1 + xd->value_len);
  89                 kfree(xd->xname);
  90         }
  91
  92         list_del_init(&xd->xindex);
  93         xd->hashkey = 0;
  94         xd->xname = NULL;
  95         xd->xvalue = NULL;
  96 }
  97
  98 static void reclaim_xattr_datum(struct jffs2_sb_info *c)
  99 {
 100         /* must be called under down_write(xattr_sem) */
 101         struct jffs2_xattr_datum *xd, *_xd;
 102         uint32_t target, before;
 103         static int index = 0;
 104         int count;
 105
 106         if (c->xdatum_mem_threshold > c->xdatum_mem_usage)
 107                 return;
 108
 109         before = c->xdatum_mem_usage;
 110         target = c->xdatum_mem_usage * 4 / 5; /* 20% reduction */
 111         for (count = 0; count < XATTRINDEX_HASHSIZE; count++) {
 112                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[index], xindex) {
 113                         if (xd->flags & JFFS2_XFLAGS_HOT) {
 114                                 xd->flags &= ~JFFS2_XFLAGS_HOT;
 115                         } else if (!(xd->flags & JFFS2_XFLAGS_BIND)) {
 116                                 unload_xattr_datum(c, xd);
 117                         }
 118                         if (c->xdatum_mem_usage <= target)
 119                                 goto out;
 120                 }
 121                 index = (index+1) % XATTRINDEX_HASHSIZE;
 122         }
 123  out:
 124         JFFS2_NOTICE("xdatum_mem_usage from %u byte to %u byte (%u byte reclaimed)\n",
 125                      before, c->xdatum_mem_usage, before - c->xdatum_mem_usage);
 126 }
 127
 128 static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 129 {
 130         /* must be called under down_write(xattr_sem) */
 131         struct jffs2_eraseblock *jeb;
 132         struct jffs2_raw_node_ref *raw;
 133         struct jffs2_raw_xattr rx;
 134         size_t readlen;
 135         uint32_t crc, offset, totlen;
 136         int rc;
 137
 138         spin_lock(&c->erase_completion_lock);
 139         offset = ref_offset(xd->node);
 140         if (ref_flags(xd->node) == REF_PRISTINE)
 141                 goto complete;
 142         spin_unlock(&c->erase_completion_lock);
 143
 144         rc = jffs2_flash_read(c, offset, sizeof(rx), &readlen, (char *)&rx);
 145         if (rc || readlen != sizeof(rx)) {
 146                 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu at %#08x\n",
 147                               rc, sizeof(rx), readlen, offset);
 148                 return rc ? rc : -EIO;
 149         }
 150         crc = crc32(0, &rx, sizeof(rx) - 4);
 151         if (crc != je32_to_cpu(rx.node_crc)) {
 152                 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
 153                             offset, je32_to_cpu(rx.hdr_crc), crc);
 154                 xd->flags |= JFFS2_XFLAGS_INVALID;
 155                 return EIO;
 156         }
 157         totlen = sizeof(rx);
 158         if (xd->version != XDATUM_DELETE_MARKER)
 159                 totlen += rx.name_len + 1 + je16_to_cpu(rx.value_len);
 160         totlen = PAD(totlen);
 161         if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
 162             || je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
 163             || je32_to_cpu(rx.totlen) != totlen
 164             || je32_to_cpu(rx.xid) != xd->xid
 165             || je32_to_cpu(rx.version) != xd->version) {
 166                 JFFS2_ERROR("inconsistent xdatum at %#08x, magic=%#04x/%#04x, "
 167                             "nodetype=%#04x/%#04x, totlen=%u/%u, xid=%u/%u, version=%u/%u\n",
 168                             offset, je16_to_cpu(rx.magic), JFFS2_MAGIC_BITMASK,
 169                             je16_to_cpu(rx.nodetype), JFFS2_NODETYPE_XATTR,
 170                             je32_to_cpu(rx.totlen), totlen,
 171                             je32_to_cpu(rx.xid), xd->xid,
 172                             je32_to_cpu(rx.version), xd->version);
 173                 xd->flags |= JFFS2_XFLAGS_INVALID;
 174                 return EIO;
 175         }
 176         xd->xprefix = rx.xprefix;
 177         xd->name_len = rx.name_len;
 178         xd->value_len = je16_to_cpu(rx.value_len);
 179         xd->data_crc = je32_to_cpu(rx.data_crc);
 180
 181         spin_lock(&c->erase_completion_lock);
 182  complete:
 183         for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
 184                 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
 185                 totlen = PAD(ref_totlen(c, jeb, raw));
 186                 if (ref_flags(raw) == REF_UNCHECKED) {
 187                         c->unchecked_size -= totlen; c->used_size += totlen;
 188                         jeb->unchecked_size -= totlen; jeb->used_size += totlen;
 189                 }
 190                 raw->flash_offset = ref_offset(raw) | ((xd->node==raw) ? REF_PRISTINE : REF_NORMAL);
 191         }
 192         spin_unlock(&c->erase_completion_lock);
 193
 194         /* unchecked xdatum is chained with c->xattr_unchecked */
 195         list_del_init(&xd->xindex);
 196
 197         dbg_xattr("success on verfying xdatum (xid=%u, version=%u)\n",
 198                   xd->xid, xd->version);
 199
 200         return 0;
 201 }
 202
 203 static int do_load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 204 {
 205         /* must be called under down_write(xattr_sem) */
 206         char *data;
 207         size_t readlen;
 208         uint32_t crc, length;
 209         int i, ret, retry = 0;
 210
 211         BUG_ON(ref_flags(xd->node) != REF_PRISTINE);
 212         BUG_ON(!list_empty(&xd->xindex));
 213  retry:
 214         length = xd->name_len + 1 + xd->value_len;
 215         data = kmalloc(length, GFP_KERNEL);
 216         if (!data)
 217                 return -ENOMEM;
 218
 219         ret = jffs2_flash_read(c, ref_offset(xd->node)+sizeof(struct jffs2_raw_xattr),
 220                                length, &readlen, data);
 221
 222         if (ret || length!=readlen) {
 223                 JFFS2_WARNING("jffs2_flash_read() returned %d, request=%d, readlen=%zu, at %#08x\n",
 224                               ret, length, readlen, ref_offset(xd->node));
 225                 kfree(data);
 226                 return ret ? ret : -EIO;
 227         }
 228
 229         data[xd->name_len] = '\0';
 230         crc = crc32(0, data, length);
 231         if (crc != xd->data_crc) {
 232                 JFFS2_WARNING("node CRC failed (JFFS2_NODETYPE_XREF)"
 233                               " at %#08x, read: 0x%08x calculated: 0x%08x\n",
 234                               ref_offset(xd->node), xd->data_crc, crc);
 235                 kfree(data);
 236                 xd->flags |= JFFS2_XFLAGS_INVALID;
 237                 return EIO;
 238         }
 239
 240         xd->flags |= JFFS2_XFLAGS_HOT;
 241         xd->xname = data;
 242         xd->xvalue = data + xd->name_len+1;
 243
 244         c->xdatum_mem_usage += length;
 245
 246         xd->hashkey = xattr_datum_hashkey(xd->xprefix, xd->xname, xd->xvalue, xd->value_len);
 247         i = xd->hashkey % XATTRINDEX_HASHSIZE;
 248         list_add(&xd->xindex, &c->xattrindex[i]);
 249         if (!retry) {
 250                 retry = 1;
 251                 reclaim_xattr_datum(c);
 252                 if (!xd->xname)
 253                         goto retry;
 254         }
 255
 256         dbg_xattr("success on loading xdatum (xid=%u, xprefix=%u, xname='%s')\n",
 257                   xd->xid, xd->xprefix, xd->xname);
 258
 259         return 0;
 260 }
 261
 262 static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 263 {
 264         /* must be called under down_write(xattr_sem);
 265          * rc < 0 : recoverable error, try again
 266          * rc = 0 : success
 267          * rc > 0 : Unrecoverable error, this node should be deleted.
 268          */
 269         int rc = 0;
 270
 271         if (xd->xname)
 272                 return 0;
 273         if (xd->flags & JFFS2_XFLAGS_INVALID)
 274                 return EIO;
 275         if (unlikely(is_xattr_datum_unchecked(c, xd)))
 276                 rc = do_verify_xattr_datum(c, xd);
 277         if (!rc)
 278                 rc = do_load_xattr_datum(c, xd);
 279         return rc;
 280 }
 281
 282 static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 283 {
 284         /* must be called under down_write(xattr_sem) */
 285         struct jffs2_raw_xattr rx;
 286         struct kvec vecs[2];
 287         size_t length;
 288         int rc, totlen, nvecs = 1;
 289         uint32_t phys_ofs = write_ofs(c);
 290
 291         BUG_ON(is_xattr_datum_dead(xd) || (xd->flags & JFFS2_XFLAGS_INVALID)
 292                ? !!xd->xname : !xd->xname);
 293
 294         vecs[0].iov_base = &rx;
 295         vecs[0].iov_len = totlen = sizeof(rx);
 296         if (!is_xattr_datum_dead(xd) && !(xd->flags & JFFS2_XFLAGS_INVALID)) {
 297                 nvecs++;
 298                 vecs[1].iov_base = xd->xname;
 299                 vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
 300                 totlen += 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         if (!is_xattr_datum_dead(xd) && !(xd->flags & JFFS2_XFLAGS_INVALID)) {
 311                 rx.version = cpu_to_je32(++xd->version);
 312                 rx.xprefix = xd->xprefix;
 313                 rx.name_len = xd->name_len;
 314                 rx.value_len = cpu_to_je16(xd->value_len);
 315                 rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
 316         } else {
 317                 rx.version = cpu_to_je32(XDATUM_DELETE_MARKER);
 318         }
 319         rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
 320
 321         rc = jffs2_flash_writev(c, vecs, nvecs, phys_ofs, &length, 0);
 322         if (rc || totlen != length) {
 323                 JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%zu, at %#08x\n",
 324                               rc, totlen, length, phys_ofs);
 325                 rc = rc ? rc : -EIO;
 326                 if (length)
 327                         jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(totlen), NULL);
 328
 329                 return rc;
 330         }
 331         /* success */
 332         jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(totlen), (void *)xd);
 333
 334         dbg_xattr("success on saving xdatum (xid=%u, version=%u, xprefix=%u, xname='%s')\n",
 335                   xd->xid, xd->version, xd->xprefix, xd->xname);
 336
 337         return 0;
 338 }
 339
 340 static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
 341                                                     int xprefix, const char *xname,
 342                                                     const char *xvalue, int xsize)
 343 {
 344         /* must be called under down_write(xattr_sem) */
 345         struct jffs2_xattr_datum *xd;
 346         uint32_t hashkey, name_len;
 347         char *data;
 348         int i, rc;
 349
 350         /* Search xattr_datum has same xname/xvalue by index */
 351         hashkey = xattr_datum_hashkey(xprefix, xname, xvalue, xsize);
 352         i = hashkey % XATTRINDEX_HASHSIZE;
 353         list_for_each_entry(xd, &c->xattrindex[i], xindex) {
 354                 if (xd->hashkey==hashkey
 355                     && xd->xprefix==xprefix
 356                     && xd->value_len==xsize
 357                     && !strcmp(xd->xname, xname)
 358                     && !memcmp(xd->xvalue, xvalue, xsize)) {
 359                         xd->refcnt++;
 360                         return xd;
 361                 }
 362         }
 363
 364         /* Not found, Create NEW XATTR-Cache */
 365         name_len = strlen(xname);
 366
 367         xd = jffs2_alloc_xattr_datum();
 368         if (!xd)
 369                 return ERR_PTR(-ENOMEM);
 370
 371         data = kmalloc(name_len + 1 + xsize, GFP_KERNEL);
 372         if (!data) {
 373                 jffs2_free_xattr_datum(xd);
 374                 return ERR_PTR(-ENOMEM);
 375         }
 376         strcpy(data, xname);
 377         memcpy(data + name_len + 1, xvalue, xsize);
 378
 379         xd->refcnt = 1;
 380         xd->xid = ++c->highest_xid;
 381         xd->flags |= JFFS2_XFLAGS_HOT;
 382         xd->xprefix = xprefix;
 383
 384         xd->hashkey = hashkey;
 385         xd->xname = data;
 386         xd->xvalue = data + name_len + 1;
 387         xd->name_len = name_len;
 388         xd->value_len = xsize;
 389         xd->data_crc = crc32(0, data, xd->name_len + 1 + xd->value_len);
 390
 391         rc = save_xattr_datum(c, xd);
 392         if (rc) {
 393                 kfree(xd->xname);
 394                 jffs2_free_xattr_datum(xd);
 395                 return ERR_PTR(rc);
 396         }
 397
 398         /* Insert Hash Index */
 399         i = hashkey % XATTRINDEX_HASHSIZE;
 400         list_add(&xd->xindex, &c->xattrindex[i]);
 401
 402         c->xdatum_mem_usage += (xd->name_len + 1 + xd->value_len);
 403         reclaim_xattr_datum(c);
 404
 405         return xd;
 406 }
 407
 408 static void delete_xattr_datum_delay(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 409 {
 410         /* must be called under down_write(xattr_sem) */
 411         BUG_ON(xd->refcnt);
 412
 413         unload_xattr_datum(c, xd);
 414         set_xattr_datum_dead(xd);
 415         spin_lock(&c->erase_completion_lock);
 416         list_add(&xd->xindex, &c->xattr_dead_list);
 417         spin_unlock(&c->erase_completion_lock);
 418         JFFS2_NOTICE("xdatum(xid=%u) was removed without delete marker. "
 419                      "An orphan xdatum may be detected on next mounting.\n", xd->xid);
 420 }
 421
 422 static void delete_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 423 {
 424         /* must be called under jffs2_reserve_space() and down_write(xattr_sem) */
 425         int rc;
 426         BUG_ON(xd->refcnt);
 427
 428         unload_xattr_datum(c, xd);
 429         set_xattr_datum_dead(xd);
 430         rc = save_xattr_datum(c, xd);
 431         if (rc) {
 432                 JFFS2_NOTICE("xdatum(xid=%u) was removed without delete marker. "
 433                              "An orphan xdatum may be detected on next mounting.\n",
 434                              xd->xid);
 435         }
 436         spin_lock(&c->erase_completion_lock);
 437         list_add(&xd->xindex, &c->xattr_dead_list);
 438         spin_unlock(&c->erase_completion_lock);
 439 }
 440
 441 /* -------- xref related functions ------------------
 442  * verify_xattr_ref(c, ref)
 443  *   is used to load xref information from medium. Because summary data does not
 444  *   contain xid/ino, it's necessary to verify once while mounting process.
 445  * delete_xattr_ref_node(c, ref)
 446  *   is used to delete a jffs2 node is dominated by xref. When EBS is enabled,
 447  *   it overwrites the obsolete node by myself.
 448  * delete_xattr_ref(c, ref)
 449  *   is used to delete jffs2_xattr_ref object. If the reference counter of xdatum
 450  *   is refered by this xref become 0, delete_xattr_datum() is called later.
 451  * save_xattr_ref(c, ref)
 452  *   is used to write xref to medium.
 453  * create_xattr_ref(c, ic, xd)
 454  *   is used to create a new xref and write to medium.
 455  * jffs2_xattr_delete_inode(c, ic)
 456  *   is called to remove xrefs related to obsolete inode when inode is unlinked.
 457  * jffs2_xattr_free_inode(c, ic)
 458  *   is called to release xattr related objects when unmounting.
 459  * check_xattr_ref_inode(c, ic)
 460  *   is used to confirm inode does not have duplicate xattr name/value pair.
 461  * -------------------------------------------------- */
 462 static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
 463 {
 464         struct jffs2_eraseblock *jeb;
 465         struct jffs2_raw_node_ref *raw;
 466         struct jffs2_raw_xref rr;
 467         size_t readlen;
 468         uint32_t crc, offset, totlen;
 469         int rc;
 470
 471         spin_lock(&c->erase_completion_lock);
 472         if (ref_flags(ref->node) != REF_UNCHECKED)
 473                 goto complete;
 474         offset = ref_offset(ref->node);
 475         spin_unlock(&c->erase_completion_lock);
 476
 477         rc = jffs2_flash_read(c, offset, sizeof(rr), &readlen, (char *)&rr);
 478         if (rc || sizeof(rr) != readlen) {
 479                 JFFS2_WARNING("jffs2_flash_read()=%d, req=%zu, read=%zu, at %#08x\n",
 480                               rc, sizeof(rr), readlen, offset);
 481                 return rc ? rc : -EIO;
 482         }
 483         /* obsolete node */
 484         crc = crc32(0, &rr, sizeof(rr) - 4);
 485         if (crc != je32_to_cpu(rr.node_crc)) {
 486                 JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
 487                             offset, je32_to_cpu(rr.node_crc), crc);
 488                 return EIO;
 489         }
 490         if (je16_to_cpu(rr.magic) != JFFS2_MAGIC_BITMASK
 491             || je16_to_cpu(rr.nodetype) != JFFS2_NODETYPE_XREF
 492             || je32_to_cpu(rr.totlen) != PAD(sizeof(rr))) {
 493                 JFFS2_ERROR("inconsistent xref at %#08x, magic=%#04x/%#04x, "
 494                             "nodetype=%#04x/%#04x, totlen=%u/%zu\n",
 495                             offset, je16_to_cpu(rr.magic), JFFS2_MAGIC_BITMASK,
 496                             je16_to_cpu(rr.nodetype), JFFS2_NODETYPE_XREF,
 497                             je32_to_cpu(rr.totlen), PAD(sizeof(rr)));
 498                 return EIO;
 499         }
 500         ref->ino = je32_to_cpu(rr.ino);
 501         ref->xid = je32_to_cpu(rr.xid);
 502         ref->xseqno = je32_to_cpu(rr.xseqno);
 503         if (ref->xseqno > c->highest_xseqno)
 504                 c->highest_xseqno = (ref->xseqno & ~XREF_DELETE_MARKER);
 505
 506         spin_lock(&c->erase_completion_lock);
 507  complete:
 508         for (raw=ref->node; raw != (void *)ref; raw=raw->next_in_ino) {
 509                 jeb = &c->blocks[ref_offset(raw) / c->sector_size];
 510                 totlen = PAD(ref_totlen(c, jeb, raw));
 511                 if (ref_flags(raw) == REF_UNCHECKED) {
 512                         c->unchecked_size -= totlen; c->used_size += totlen;
 513                         jeb->unchecked_size -= totlen; jeb->used_size += totlen;
 514                 }
 515                 raw->flash_offset = ref_offset(raw) | ((ref->node==raw) ? REF_PRISTINE : REF_NORMAL);
 516         }
 517         spin_unlock(&c->erase_completion_lock);
 518
 519         dbg_xattr("success on verifying xref (ino=%u, xid=%u) at %#08x\n",
 520                   ref->ino, ref->xid, ref_offset(ref->node));
 521         return 0;
 522 }
 523
 524 static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
 525 {
 526         /* must be called under down_write(xattr_sem) */
 527         struct jffs2_raw_xref rr;
 528         size_t length;
 529         uint32_t xseqno, phys_ofs = write_ofs(c);
 530         int ret;
 531
 532         rr.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
 533         rr.nodetype = cpu_to_je16(JFFS2_NODETYPE_XREF);
 534         rr.totlen = cpu_to_je32(PAD(sizeof(rr)));
 535         rr.hdr_crc = cpu_to_je32(crc32(0, &rr, sizeof(struct jffs2_unknown_node) - 4));
 536
 537         xseqno = (c->highest_xseqno += 2);
 538         if (is_xattr_ref_dead(ref)) {
 539                 xseqno |= XREF_DELETE_MARKER;
 540                 rr.ino = cpu_to_je32(ref->ino);
 541                 rr.xid = cpu_to_je32(ref->xid);
 542         } else {
 543                 rr.ino = cpu_to_je32(ref->ic->ino);
 544                 rr.xid = cpu_to_je32(ref->xd->xid);
 545         }
 546         rr.xseqno = cpu_to_je32(xseqno);
 547         rr.node_crc = cpu_to_je32(crc32(0, &rr, sizeof(rr) - 4));
 548
 549         ret = jffs2_flash_write(c, phys_ofs, sizeof(rr), &length, (char *)&rr);
 550         if (ret || sizeof(rr) != length) {
 551                 JFFS2_WARNING("jffs2_flash_write() returned %d, request=%zu, retlen=%zu, at %#08x\n",
 552                               ret, sizeof(rr), length, phys_ofs);
 553                 ret = ret ? ret : -EIO;
 554                 if (length)
 555                         jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, PAD(sizeof(rr)), NULL);
 556
 557                 return ret;
 558         }
 559         /* success */
 560         ref->xseqno = xseqno;
 561         jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, PAD(sizeof(rr)), (void *)ref);
 562
 563         dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid);
 564
 565         return 0;
 566 }
 567
 568 static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic,
 569                                                 struct jffs2_xattr_datum *xd)
 570 {
 571         /* must be called under down_write(xattr_sem) */
 572         struct jffs2_xattr_ref *ref;
 573         int ret;
 574
 575         ref = jffs2_alloc_xattr_ref();
 576         if (!ref)
 577                 return ERR_PTR(-ENOMEM);
 578         ref->ic = ic;
 579         ref->xd = xd;
 580
 581         ret = save_xattr_ref(c, ref);
 582         if (ret) {
 583                 jffs2_free_xattr_ref(ref);
 584                 return ERR_PTR(ret);
 585         }
 586
 587         /* Chain to inode */
 588         ref->next = ic->xref;
 589         ic->xref = ref;
 590
 591         return ref; /* success */
 592 }
 593
 594 static void delete_xattr_ref_delay(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
 595 {
 596         /* must be called under down_write(xattr_sem) */
 597         struct jffs2_xattr_datum *xd;
 598
 599         set_xattr_ref_dead(ref);
 600         xd = ref->xd;
 601         ref->ino = ref->ic->ino;
 602         ref->xid = ref->xd->xid;
 603         spin_lock(&c->erase_completion_lock);
 604         ref->next = c->xref_dead_list;
 605         c->xref_dead_list = ref;
 606         spin_unlock(&c->erase_completion_lock);
 607
 608         JFFS2_NOTICE("xref(ino=%u, xid=%u) was removed without delete marker. "
 609                      "An orphan xref may be detected on next mounting.\n",
 610                      ref->ino, ref->xid);
 611
 612         if (!--xd->refcnt)
 613                 delete_xattr_datum_delay(c, xd);
 614 }
 615
 616 static int delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref, int enforce)
 617 {
 618         /* must be called under jffs2_reserve_space() and down_write(xattr_sem) */
 619         struct jffs2_inode_cache *ic;
 620         struct jffs2_xattr_datum *xd;
 621         uint32_t length;
 622         int rc;
 623
 624         set_xattr_ref_dead(ref);
 625         ic = ref->ic;
 626         xd = ref->xd;
 627         ref->ino = ic->ino;
 628         ref->xid = xd->xid;
 629         rc = save_xattr_ref(c, ref);
 630         if (rc) {
 631                 if (!enforce) {
 632                         clr_xattr_ref_dead(ref);
 633                         ref->ic = ic;
 634                         ref->xd = xd;
 635                         return rc;
 636                 }
 637                 JFFS2_WARNING("could not write delete marker of xref(ino=%u, xid=%u). "
 638                               "An orphan xref may be detected on next mounting.\n",
 639                               ref->ic->ino, ref->xd->xid);
 640         }
 641         spin_lock(&c->erase_completion_lock);
 642         ref->next = c->xref_dead_list;
 643         c->xref_dead_list = ref;
 644         spin_unlock(&c->erase_completion_lock);
 645
 646         xd->refcnt--;
 647         if (xd->refcnt)
 648                 return 0;
 649
 650         /* delete xdatum */
 651         unload_xattr_datum(c, xd);
 652         up_write(&c->xattr_sem);
 653         jffs2_complete_reservation(c);
 654
 655         rc = jffs2_reserve_space(c, PAD(sizeof(struct jffs2_raw_xattr)), &length,
 656                                  ALLOC_DELETION, JFFS2_SUMMARY_XATTR_SIZE);
 657         if (rc) {
 658                 down(&c->alloc_sem);
 659                 down_write(&c->xattr_sem);
 660                 delete_xattr_datum_delay(c, xd);
 661         } else {
 662                 down_write(&c->xattr_sem);
 663                 delete_xattr_datum(c, xd);
 664         }
 665         return 0;
 666 }
 667
 668 void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
 669 {
 670         /* It's called from jffs2_clear_inode() on inode removing.
 671            When an inode with XATTR is removed, those XATTRs must be removed. */
 672         struct jffs2_xattr_ref *ref;
 673         uint32_t length;
 674         int rc, retry;
 675
 676         if (!ic || ic->nlink > 0)
 677                 return;
 678
 679         down_read(&c->xattr_sem);
 680         if (!ic->xref) {
 681                 up_read(&c->xattr_sem);
 682                 return;
 683         }
 684         up_read(&c->xattr_sem);
 685  retry:
 686         rc = jffs2_reserve_space(c, PAD(sizeof(struct jffs2_raw_xref)), &length,
 687                                  ALLOC_DELETION, JFFS2_SUMMARY_XREF_SIZE);
 688         down_write(&c->xattr_sem);
 689         if (ic->xref) {
 690                 ref = ic->xref;
 691                 ic->xref = ref->next;
 692                 if (rc) {
 693                         delete_xattr_ref_delay(c, ref);
 694                 } else {
 695                         delete_xattr_ref(c, ref, 1);
 696                 }
 697         }
 698         retry = ic->xref ? 1 : 0;
 699         up_write(&c->xattr_sem);
 700         if (!rc)
 701                 jffs2_complete_reservation(c);
 702         if (retry)
 703                 goto retry;
 704 }
 705
 706 void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
 707 {
 708         /* It's called from jffs2_free_ino_caches() until unmounting FS. */
 709         struct jffs2_xattr_datum *xd;
 710         struct jffs2_xattr_ref *ref, *_ref;
 711
 712         down_write(&c->xattr_sem);
 713         for (ref = ic->xref; ref; ref = _ref) {
 714                 _ref = ref->next;
 715                 xd = ref->xd;
 716                 xd->refcnt--;
 717                 if (!xd->refcnt) {
 718                         unload_xattr_datum(c, xd);
 719                         jffs2_free_xattr_datum(xd);
 720                 }
 721                 jffs2_free_xattr_ref(ref);
 722         }
 723         ic->xref = NULL;
 724         up_write(&c->xattr_sem);
 725 }
 726
 727 static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
 728 {
 729         /* success of check_xattr_ref_inode() means taht inode (ic) dose not have
 730          * duplicate name/value pairs. If duplicate name/value pair would be found,
 731          * one will be removed.
 732          */
 733         struct jffs2_xattr_ref *ref, *cmp, **pref, **pcmp;
 734         int rc = 0;
 735
 736         if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
 737                 return 0;
 738         down_write(&c->xattr_sem);
 739  retry:
 740         rc = 0;
 741         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
 742                 if (!ref->xd->xname) {
 743                         rc = load_xattr_datum(c, ref->xd);
 744                         if (unlikely(rc > 0)) {
 745                                 *pref = ref->next;
 746                                 delete_xattr_ref_delay(c, ref);
 747                                 goto retry;
 748                         } else if (unlikely(rc < 0))
 749                                 goto out;
 750                 }
 751                 for (cmp=ref->next, pcmp=&ref->next; cmp; pcmp=&cmp->next, cmp=cmp->next) {
 752                         if (!cmp->xd->xname) {
 753                                 ref->xd->flags |= JFFS2_XFLAGS_BIND;
 754                                 rc = load_xattr_datum(c, cmp->xd);
 755                                 ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
 756                                 if (unlikely(rc > 0)) {
 757                                         *pcmp = cmp->next;
 758                                         delete_xattr_ref_delay(c, cmp);
 759                                         goto retry;
 760                                 } else if (unlikely(rc < 0))
 761                                         goto out;
 762                         }
 763                         if (ref->xd->xprefix == cmp->xd->xprefix
 764                             && !strcmp(ref->xd->xname, cmp->xd->xname)) {
 765                                 if (ref->xseqno > cmp->xseqno) {
 766                                         *pcmp = cmp->next;
 767                                         delete_xattr_ref_delay(c, cmp);
 768                                 } else {
 769                                         *pref = ref->next;
 770                                         delete_xattr_ref_delay(c, ref);
 771                                 }
 772                                 goto retry;
 773                         }
 774                 }
 775         }
 776         ic->flags |= INO_FLAGS_XATTR_CHECKED;
 777  out:
 778         up_write(&c->xattr_sem);
 779
 780         return rc;
 781 }
 782
 783 /* -------- xattr subsystem functions ---------------
 784  * jffs2_init_xattr_subsystem(c)
 785  *   is used to initialize semaphore and list_head, and some variables.
 786  * jffs2_find_xattr_datum(c, xid)
 787  *   is used to lookup xdatum while scanning process.
 788  * jffs2_clear_xattr_subsystem(c)
 789  *   is used to release any xattr related objects.
 790  * jffs2_build_xattr_subsystem(c)
 791  *   is used to associate xdatum and xref while super block building process.
 792  * jffs2_setup_xattr_datum(c, xid, version)
 793  *   is used to insert xdatum while scanning process.
 794  * -------------------------------------------------- */
 795 void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
 796 {
 797         int i;
 798
 799         for (i=0; i < XATTRINDEX_HASHSIZE; i++)
 800                 INIT_LIST_HEAD(&c->xattrindex[i]);
 801         INIT_LIST_HEAD(&c->xattr_unchecked);
 802         INIT_LIST_HEAD(&c->xattr_dead_list);
 803         c->xref_dead_list = NULL;
 804         c->xref_temp = NULL;
 805
 806         init_rwsem(&c->xattr_sem);
 807         c->highest_xid = 0;
 808         c->highest_xseqno = 0;
 809         c->xdatum_mem_usage = 0;
 810         c->xdatum_mem_threshold = 32 * 1024;    /* Default 32KB */
 811 }
 812
 813 static struct jffs2_xattr_datum *jffs2_find_xattr_datum(struct jffs2_sb_info *c, uint32_t xid)
 814 {
 815         struct jffs2_xattr_datum *xd;
 816         int i = xid % XATTRINDEX_HASHSIZE;
 817
 818         /* It's only used in scanning/building process. */
 819         BUG_ON(!(c->flags & (JFFS2_SB_FLAG_SCANNING|JFFS2_SB_FLAG_BUILDING)));
 820
 821         list_for_each_entry(xd, &c->xattrindex[i], xindex) {
 822                 if (xd->xid==xid)
 823                         return xd;
 824         }
 825         return NULL;
 826 }
 827
 828 void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
 829 {
 830         struct jffs2_xattr_datum *xd, *_xd;
 831         struct jffs2_xattr_ref *ref, *_ref;
 832         int i;
 833
 834         for (ref=c->xref_temp; ref; ref = _ref) {
 835                 _ref = ref->next;
 836                 jffs2_free_xattr_ref(ref);
 837         }
 838
 839         for (ref=c->xref_dead_list; ref; ref = _ref) {
 840                 _ref = ref->next;
 841                 jffs2_free_xattr_ref(ref);
 842         }
 843
 844         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
 845                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
 846                         list_del(&xd->xindex);
 847                         if (xd->xname)
 848                                 kfree(xd->xname);
 849                         jffs2_free_xattr_datum(xd);
 850                 }
 851         }
 852
 853         list_for_each_entry_safe(xd, _xd, &c->xattr_dead_list, xindex) {
 854                 list_del(&xd->xindex);
 855                 jffs2_free_xattr_datum(xd);
 856         }
 857 }
 858
 859 #define XREF_TMPHASH_SIZE       (128)
 860 void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
 861 {
 862         struct jffs2_xattr_ref *ref, *_ref;
 863         struct jffs2_xattr_ref *xref_tmphash[XREF_TMPHASH_SIZE];
 864         struct jffs2_xattr_datum *xd, *_xd;
 865         struct jffs2_inode_cache *ic;
 866         struct jffs2_raw_node_ref *raw;
 867         int i, xdatum_count = 0, xdatum_unchecked_count = 0, xref_count = 0;
 868
 869         BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
 870         /* Phase.1 : Drop dead xdatum */
 871         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
 872                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
 873                         BUG_ON(xd->node == (void *)xd);
 874                         if (is_xattr_datum_dead(xd)) {
 875                                 list_del_init(&xd->xindex);
 876                                 list_add(&xd->xindex, &c->xattr_unchecked);
 877                         }
 878                 }
 879         }
 880
 881         /* Phase.2 : Merge same xref */
 882         for (i=0; i < XREF_TMPHASH_SIZE; i++)
 883                 xref_tmphash[i] = NULL;
 884         for (ref=c->xref_temp; ref; ref=_ref) {
 885                 struct jffs2_xattr_ref *tmp;
 886
 887                 _ref = ref->next;
 888                 if (ref_flags(ref->node) != REF_PRISTINE) {
 889                         if (verify_xattr_ref(c, ref)) {
 890                                 BUG_ON(ref->node->next_in_ino != (void *)ref);
 891                                 ref->node->next_in_ino = NULL;
 892                                 jffs2_mark_node_obsolete(c, ref->node);
 893                                 jffs2_free_xattr_ref(ref);
 894                                 continue;
 895                         }
 896                 }
 897
 898                 i = (ref->ino ^ ref->xid) % XREF_TMPHASH_SIZE;
 899                 for (tmp=xref_tmphash[i]; tmp; tmp=tmp->next) {
 900                         if (tmp->ino == ref->ino && tmp->xid == ref->xid)
 901                                 break;
 902                 }
 903                 if (tmp) {
 904                         raw = ref->node;
 905                         if (ref->xseqno > tmp->xseqno) {
 906                                 tmp->xseqno = ref->xseqno;
 907                                 raw->next_in_ino = tmp->node;
 908                                 tmp->node = raw;
 909                         } else {
 910                                 raw->next_in_ino = tmp->node->next_in_ino;
 911                                 tmp->node->next_in_ino = raw;
 912                         }
 913                         jffs2_free_xattr_ref(ref);
 914                         continue;
 915                 } else {
 916                         ref->next = xref_tmphash[i];
 917                         xref_tmphash[i] = ref;
 918                 }
 919         }
 920         c->xref_temp = NULL;
 921
 922         /* Phase.3 : Bind xref with inode_cache and xattr_datum */
 923         for (i=0; i < XREF_TMPHASH_SIZE; i++) {
 924                 for (ref=xref_tmphash[i]; ref; ref=_ref) {
 925                         _ref = ref->next;
 926                         if (is_xattr_ref_dead(ref)) {
 927                                 ref->next = c->xref_dead_list;
 928                                 c->xref_dead_list = ref;
 929                                 continue;
 930                         }
 931                         /* At this point, ref->xid and ref->ino contain XID and inode number.
 932                            ref->xd and ref->ic are not valid yet. */
 933                         xd = jffs2_find_xattr_datum(c, ref->xid);
 934                         ic = jffs2_get_ino_cache(c, ref->ino);
 935                         if (!xd || !ic) {
 936                                 JFFS2_WARNING("xref(ino=%u, xid=%u, xseqno=%u) is orphan. \n",
 937                                               ref->ino, ref->xid, ref->xseqno);
 938                                 set_xattr_ref_dead(ref);
 939                                 ref->next = c->xref_dead_list;
 940                                 c->xref_dead_list = ref;
 941                                 continue;
 942                         }
 943                         ref->xd = xd;
 944                         ref->ic = ic;
 945                         xd->refcnt++;
 946                         ref->next = ic->xref;
 947                         ic->xref = ref;
 948                         xref_count++;
 949                 }
 950         }
 951
 952         /* Phase.4 : Link unchecked xdatum to xattr_unchecked list */
 953         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
 954                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
 955                         list_del_init(&xd->xindex);
 956                         if (!xd->refcnt) {
 957                                 JFFS2_WARNING("orphan xdatum(xid=%u, version=%u)\n",
 958                                               xd->xid, xd->version);
 959                                 set_xattr_datum_dead(xd);
 960                                 list_add(&xd->xindex, &c->xattr_unchecked);
 961                                 continue;
 962                         }
 963                         if (is_xattr_datum_unchecked(c, xd)) {
 964                                 dbg_xattr("unchecked xdatum(xid=%u, version=%u)\n",
 965                                           xd->xid, xd->version);
 966                                 list_add(&xd->xindex, &c->xattr_unchecked);
 967                                 xdatum_unchecked_count++;
 968                         }
 969                         xdatum_count++;
 970                 }
 971         }
 972         /* build complete */
 973         JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum (%u unchecked) and "
 974                      "%u of xref found.\n", xdatum_count, xdatum_unchecked_count, xref_count);
 975 }
 976
 977 struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
 978                                                   uint32_t xid, uint32_t version)
 979 {
 980         struct jffs2_xattr_datum *xd;
 981
 982         xd = jffs2_find_xattr_datum(c, xid);
 983         if (!xd) {
 984                 xd = jffs2_alloc_xattr_datum();
 985                 if (!xd)
 986                         return ERR_PTR(-ENOMEM);
 987                 xd->xid = xid;
 988                 xd->version = version;
 989                 if (xd->xid > c->highest_xid)
 990                         c->highest_xid = xd->xid;
 991                 list_add_tail(&xd->xindex, &c->xattrindex[xid % XATTRINDEX_HASHSIZE]);
 992         }
 993         return xd;
 994 }
 995
 996 /* -------- xattr subsystem functions ---------------
 997  * xprefix_to_handler(xprefix)
 998  *   is used to translate xprefix into xattr_handler.
 999  * jffs2_listxattr(dentry, buffer, size)
1000  *   is an implementation of listxattr handler on jffs2.
1001  * do_jffs2_getxattr(inode, xprefix, xname, buffer, size)
1002  *   is an implementation of getxattr handler on jffs2.
1003  * do_jffs2_setxattr(inode, xprefix, xname, buffer, size, flags)
1004  *   is an implementation of setxattr handler on jffs2.
1005  * -------------------------------------------------- */
1006 struct xattr_handler *jffs2_xattr_handlers[] = {
1007         &jffs2_user_xattr_handler,
1008 #ifdef CONFIG_JFFS2_FS_SECURITY
1009         &jffs2_security_xattr_handler,
1010 #endif
1011 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
1012         &jffs2_acl_access_xattr_handler,
1013         &jffs2_acl_default_xattr_handler,
1014 #endif
1015         &jffs2_trusted_xattr_handler,
1016         NULL
1017 };
1018
1019 static struct xattr_handler *xprefix_to_handler(int xprefix) {
1020         struct xattr_handler *ret;
1021
1022         switch (xprefix) {
1023         case JFFS2_XPREFIX_USER:
1024                 ret = &jffs2_user_xattr_handler;
1025                 break;
1026 #ifdef CONFIG_JFFS2_FS_SECURITY
1027         case JFFS2_XPREFIX_SECURITY:
1028                 ret = &jffs2_security_xattr_handler;
1029                 break;
1030 #endif
1031 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
1032         case JFFS2_XPREFIX_ACL_ACCESS:
1033                 ret = &jffs2_acl_access_xattr_handler;
1034                 break;
1035         case JFFS2_XPREFIX_ACL_DEFAULT:
1036                 ret = &jffs2_acl_default_xattr_handler;
1037                 break;
1038 #endif
1039         case JFFS2_XPREFIX_TRUSTED:
1040                 ret = &jffs2_trusted_xattr_handler;
1041                 break;
1042         default:
1043                 ret = NULL;
1044                 break;
1045         }
1046         return ret;
1047 }
1048
1049 ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
1050 {
1051         struct inode *inode = dentry->d_inode;
1052         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1053         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1054         struct jffs2_inode_cache *ic = f->inocache;
1055         struct jffs2_xattr_ref *ref, **pref;
1056         struct jffs2_xattr_datum *xd;
1057         struct xattr_handler *xhandle;
1058         ssize_t len, rc;
1059         int retry = 0;
1060
1061         rc = check_xattr_ref_inode(c, ic);
1062         if (unlikely(rc))
1063                 return rc;
1064
1065         down_read(&c->xattr_sem);
1066  retry:
1067         len = 0;
1068         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1069                 BUG_ON(ref->ic != ic);
1070                 xd = ref->xd;
1071                 if (!xd->xname) {
1072                         /* xdatum is unchached */
1073                         if (!retry) {
1074                                 retry = 1;
1075                                 up_read(&c->xattr_sem);
1076                                 down_write(&c->xattr_sem);
1077                                 goto retry;
1078                         } else {
1079                                 rc = load_xattr_datum(c, xd);
1080                                 if (unlikely(rc > 0)) {
1081                                         *pref = ref->next;
1082                                         delete_xattr_ref_delay(c, ref);
1083                                         goto retry;
1084                                 } else if (unlikely(rc < 0))
1085                                         goto out;
1086                         }
1087                 }
1088                 xhandle = xprefix_to_handler(xd->xprefix);
1089                 if (!xhandle)
1090                         continue;
1091                 if (buffer) {
1092                         rc = xhandle->list(inode, buffer+len, size-len, xd->xname, xd->name_len);
1093                 } else {
1094                         rc = xhandle->list(inode, NULL, 0, xd->xname, xd->name_len);
1095                 }
1096                 if (rc < 0)
1097                         goto out;
1098                 len += rc;
1099         }
1100         rc = len;
1101  out:
1102         if (!retry) {
1103                 up_read(&c->xattr_sem);
1104         } else {
1105                 up_write(&c->xattr_sem);
1106         }
1107         return rc;
1108 }
1109
1110 int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
1111                       char *buffer, size_t size)
1112 {
1113         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1114         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1115         struct jffs2_inode_cache *ic = f->inocache;
1116         struct jffs2_xattr_datum *xd;
1117         struct jffs2_xattr_ref *ref, **pref;
1118         int rc, retry = 0;
1119
1120         rc = check_xattr_ref_inode(c, ic);
1121         if (unlikely(rc))
1122                 return rc;
1123
1124         down_read(&c->xattr_sem);
1125  retry:
1126         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1127                 BUG_ON(ref->ic!=ic);
1128
1129                 xd = ref->xd;
1130                 if (xd->xprefix != xprefix)
1131                         continue;
1132                 if (!xd->xname) {
1133                         /* xdatum is unchached */
1134                         if (!retry) {
1135                                 retry = 1;
1136                                 up_read(&c->xattr_sem);
1137                                 down_write(&c->xattr_sem);
1138                                 goto retry;
1139                         } else {
1140                                 rc = load_xattr_datum(c, xd);
1141                                 if (unlikely(rc > 0)) {
1142                                         *pref = ref->next;
1143                                         delete_xattr_ref_delay(c, ref);
1144                                         goto retry;
1145                                 } else if (unlikely(rc < 0)) {
1146                                         goto out;
1147                                 }
1148                         }
1149                 }
1150                 if (!strcmp(xname, xd->xname)) {
1151                         rc = xd->value_len;
1152                         if (buffer) {
1153                                 if (size < rc) {
1154                                         rc = -ERANGE;
1155                                 } else {
1156                                         memcpy(buffer, xd->xvalue, rc);
1157                                 }
1158                         }
1159                         goto out;
1160                 }
1161         }
1162         rc = -ENODATA;
1163  out:
1164         if (!retry) {
1165                 up_read(&c->xattr_sem);
1166         } else {
1167                 up_write(&c->xattr_sem);
1168         }
1169         return rc;
1170 }
1171
1172 int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
1173                       const char *buffer, size_t size, int flags)
1174 {
1175         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
1176         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
1177         struct jffs2_inode_cache *ic = f->inocache;
1178         struct jffs2_xattr_datum *xd;
1179         struct jffs2_xattr_ref *ref, *newref, **pref;
1180         uint32_t length, request;
1181         int rc;
1182
1183         rc = check_xattr_ref_inode(c, ic);
1184         if (unlikely(rc))
1185                 return rc;
1186
1187         request = PAD(sizeof(struct jffs2_raw_xattr) + strlen(xname) + 1 + size);
1188         rc = jffs2_reserve_space(c, request, &length,
1189                                  ALLOC_NORMAL, JFFS2_SUMMARY_XATTR_SIZE);
1190         if (rc) {
1191                 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1192                 return rc;
1193         }
1194
1195         /* Find existing xattr */
1196         down_write(&c->xattr_sem);
1197  retry:
1198         for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
1199                 xd = ref->xd;
1200                 if (xd->xprefix != xprefix)
1201                         continue;
1202                 if (!xd->xname) {
1203                         rc = load_xattr_datum(c, xd);
1204                         if (unlikely(rc > 0)) {
1205                                 *pref = ref->next;
1206                                 delete_xattr_ref_delay(c, ref);
1207                                 goto retry;
1208                         } else if (unlikely(rc < 0))
1209                                 goto out;
1210                 }
1211                 if (!strcmp(xd->xname, xname)) {
1212                         if (flags & XATTR_CREATE) {
1213                                 rc = -EEXIST;
1214                                 goto out;
1215                         }
1216                         if (!buffer) {
1217                                 *pref = ref->next;
1218                                 rc = delete_xattr_ref(c, ref, 0);
1219                                 goto out;
1220                         }
1221                         goto found;
1222                 }
1223         }
1224         /* not found */
1225         if (flags & XATTR_REPLACE) {
1226                 rc = -ENODATA;
1227                 goto out;
1228         }
1229         if (!buffer) {
1230                 rc = -ENODATA;
1231                 goto out;
1232         }
1233  found:
1234         xd = create_xattr_datum(c, xprefix, xname, buffer, size);
1235         if (IS_ERR(xd)) {
1236                 rc = PTR_ERR(xd);
1237                 goto out;
1238         }
1239         up_write(&c->xattr_sem);
1240         jffs2_complete_reservation(c);
1241
1242         /* create xattr_ref */
1243         request = PAD(sizeof(struct jffs2_raw_xref));
1244         rc = jffs2_reserve_space(c, request, &length,
1245                                  ALLOC_NORMAL, JFFS2_SUMMARY_XREF_SIZE);
1246         down_write(&c->xattr_sem);
1247         if (rc) {
1248                 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1249                 xd->refcnt--;
1250                 if (!xd->refcnt)
1251                         delete_xattr_datum_delay(c, xd);
1252                 up_write(&c->xattr_sem);
1253                 return rc;
1254         }
1255         if (ref)
1256                 *pref = ref->next;
1257         newref = create_xattr_ref(c, ic, xd);
1258         if (IS_ERR(newref)) {
1259                 if (ref) {
1260                         ref->next = ic->xref;
1261                         ic->xref = ref;
1262                 }
1263                 rc = PTR_ERR(newref);
1264                 xd->refcnt--;
1265                 if (!xd->refcnt)
1266                         delete_xattr_datum_delay(c, xd);
1267         } else if (ref) {
1268                 up_write(&c->xattr_sem);
1269                 jffs2_complete_reservation(c);
1270
1271                 rc = jffs2_reserve_space(c, request, &length,
1272                                          ALLOC_DELETION, JFFS2_SUMMARY_XREF_SIZE);
1273                 down_write(&c->xattr_sem);
1274                 if (rc) {
1275                         JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
1276                         delete_xattr_ref_delay(c, ref);
1277                         up_write(&c->xattr_sem);
1278                         return 0;
1279                 }
1280                 delete_xattr_ref(c, ref, 1);
1281         }
1282  out:
1283         up_write(&c->xattr_sem);
1284         jffs2_complete_reservation(c);
1285         return rc;
1286 }
1287
1288 /* -------- garbage collector functions -------------
1289  * jffs2_garbage_collect_xattr_datum(c, xd, raw)
1290  *   is used to move xdatum into new node.
1291  * jffs2_garbage_collect_xattr_ref(c, ref, raw)
1292  *   is used to move xref into new node.
1293  * jffs2_verify_xattr(c)
1294  *   is used to call do_verify_xattr_datum() before garbage collecting.
1295  * -------------------------------------------------- */
1296 int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
1297                                       struct jffs2_raw_node_ref *raw)
1298 {
1299         uint32_t totlen, length, old_ofs;
1300         int rc = 0;
1301
1302         down_write(&c->xattr_sem);
1303         if (xd->node != raw)
1304                 goto out;
1305         if (is_xattr_datum_dead(xd) && (raw->next_in_ino == (void *)xd))
1306                 goto out;
1307
1308         old_ofs = ref_offset(xd->node);
1309         totlen = ref_totlen(c, c->gcblock, xd->node);
1310
1311         if (!is_xattr_datum_dead(xd)) {
1312                 rc = load_xattr_datum(c, xd);
1313                 if (unlikely(rc < 0))
1314                         goto out;
1315         }
1316
1317         rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XATTR_SIZE);
1318         if (rc) {
1319                 JFFS2_WARNING("jffs2_reserve_space_gc()=%d, request=%u\n", rc, totlen);
1320                 rc = rc ? rc : -EBADFD;
1321                 goto out;
1322         }
1323         rc = save_xattr_datum(c, xd);
1324         if (!rc)
1325                 dbg_xattr("xdatum (xid=%u, version=%u) GC'ed from %#08x to %08x\n",
1326                           xd->xid, xd->version, old_ofs, ref_offset(xd->node));
1327  out:
1328         if (!rc)
1329                 jffs2_mark_node_obsolete(c, raw);
1330         up_write(&c->xattr_sem);
1331         return rc;
1332 }
1333
1334
1335 int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
1336                                     struct jffs2_raw_node_ref *raw)
1337 {
1338         uint32_t totlen, length, old_ofs;
1339         int rc = 0;
1340
1341         down_write(&c->xattr_sem);
1342         BUG_ON(!ref->node);
1343
1344         if (ref->node != raw)
1345                 goto out;
1346         if (is_xattr_ref_dead(ref) && (raw->next_in_ino == (void *)ref))
1347                 goto out;
1348
1349         old_ofs = ref_offset(ref->node);
1350         totlen = ref_totlen(c, c->gcblock, ref->node);
1351
1352         rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XREF_SIZE);
1353         if (rc) {
1354                 JFFS2_WARNING("%s: jffs2_reserve_space_gc() = %d, request = %u\n",
1355                               __FUNCTION__, rc, totlen);
1356                 rc = rc ? rc : -EBADFD;
1357                 goto out;
1358         }
1359         rc = save_xattr_ref(c, ref);
1360         if (!rc)
1361                 dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n",
1362                           ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node));
1363  out:
1364         if (!rc)
1365                 jffs2_mark_node_obsolete(c, raw);
1366         up_write(&c->xattr_sem);
1367         return rc;
1368 }
1369
1370 int jffs2_verify_xattr(struct jffs2_sb_info *c)
1371 {
1372         struct jffs2_xattr_datum *xd, *_xd;
1373         struct jffs2_eraseblock *jeb;
1374         struct jffs2_raw_node_ref *raw;
1375         uint32_t totlen;
1376         int rc;
1377
1378         down_write(&c->xattr_sem);
1379         list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
1380                 rc = do_verify_xattr_datum(c, xd);
1381                 if (rc < 0)
1382                         continue;
1383                 list_del_init(&xd->xindex);
1384                 spin_lock(&c->erase_completion_lock);
1385                 for (raw=xd->node; raw != (void *)xd; raw=raw->next_in_ino) {
1386                         if (ref_flags(raw) != REF_UNCHECKED)
1387                                 continue;
1388                         jeb = &c->blocks[ref_offset(raw) / c->sector_size];
1389                         totlen = PAD(ref_totlen(c, jeb, raw));
1390                         c->unchecked_size -= totlen; c->used_size += totlen;
1391                         jeb->unchecked_size -= totlen; jeb->used_size += totlen;
1392                         raw->flash_offset = ref_offset(raw)
1393                                 | ((xd->node == (void *)raw) ? REF_PRISTINE : REF_NORMAL);
1394                 }
1395                 if (is_xattr_datum_dead(xd))
1396                         list_add(&xd->xindex, &c->xattr_dead_list);
1397                 spin_unlock(&c->erase_completion_lock);
1398         }
1399         up_write(&c->xattr_sem);
1400         return list_empty(&c->xattr_unchecked) ? 1 : 0;
1401 }
1402
1403 void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
1404 {
1405         /* must be called under spin_lock(&c->erase_completion_lock) */
1406         if (xd->node != (void *)xd)
1407                 return;
1408
1409         list_del(&xd->xindex);
1410         jffs2_free_xattr_datum(xd);
1411 }
1412
1413 void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
1414 {
1415         /* must be called under spin_lock(&c->erase_completion_lock) */
1416         struct jffs2_xattr_ref *tmp, **ptmp;
1417
1418         if (ref->node != (void *)ref)
1419                 return;
1420
1421         for (tmp=c->xref_dead_list, ptmp=&c->xref_dead_list; tmp; ptmp=&tmp->next, tmp=tmp->next) {
1422                 if (ref == tmp) {
1423                         *ptmp = tmp->next;
1424                         jffs2_free_xattr_ref(ref);
1425                         break;
1426                 }
1427         }
1428 }