fs/ceph/xattr.c

   1 #include <linux/ceph/ceph_debug.h>
   2
   3 #include "super.h"
   4 #include "mds_client.h"
   5
   6 #include <linux/ceph/decode.h>
   7
   8 #include <linux/xattr.h>
   9 #include <linux/slab.h>
  10
  11 #define XATTR_CEPH_PREFIX "ceph."
  12 #define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)
  13
  14 static bool ceph_is_valid_xattr(const char *name)
  15 {
  16         return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
  17                !strncmp(name, XATTR_SECURITY_PREFIX,
  18                         XATTR_SECURITY_PREFIX_LEN) ||
  19                !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
  20                !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
  21 }
  22
  23 /*
  24  * These define virtual xattrs exposing the recursive directory
  25  * statistics and layout metadata.
  26  */
  27 struct ceph_vxattr {
  28         char *name;
  29         size_t name_size;       /* strlen(name) + 1 (for '\0') */
  30         size_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
  31                               size_t size);
  32         bool readonly;
  33 };
  34
  35 /* directories */
  36
  37 static size_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
  38                                         size_t size)
  39 {
  40         return snprintf(val, size, "%lld", ci->i_files + ci->i_subdirs);
  41 }
  42
  43 static size_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
  44                                       size_t size)
  45 {
  46         return snprintf(val, size, "%lld", ci->i_files);
  47 }
  48
  49 static size_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
  50                                         size_t size)
  51 {
  52         return snprintf(val, size, "%lld", ci->i_subdirs);
  53 }
  54
  55 static size_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
  56                                          size_t size)
  57 {
  58         return snprintf(val, size, "%lld", ci->i_rfiles + ci->i_rsubdirs);
  59 }
  60
  61 static size_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
  62                                        size_t size)
  63 {
  64         return snprintf(val, size, "%lld", ci->i_rfiles);
  65 }
  66
  67 static size_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
  68                                          size_t size)
  69 {
  70         return snprintf(val, size, "%lld", ci->i_rsubdirs);
  71 }
  72
  73 static size_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
  74                                        size_t size)
  75 {
  76         return snprintf(val, size, "%lld", ci->i_rbytes);
  77 }
  78
  79 static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
  80                                        size_t size)
  81 {
  82         return snprintf(val, size, "%ld.09%ld", (long)ci->i_rctime.tv_sec,
  83                         (long)ci->i_rctime.tv_nsec);
  84 }
  85
  86 #define CEPH_XATTR_NAME(_type, _name)   XATTR_CEPH_PREFIX #_type "." #_name
  87
  88 #define XATTR_NAME_CEPH(_type, _name) \
  89                 { \
  90                         .name = CEPH_XATTR_NAME(_type, _name), \
  91                         .name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
  92                         .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
  93                         .readonly = true, \
  94                 }
  95
  96 static struct ceph_vxattr ceph_dir_vxattrs[] = {
  97         XATTR_NAME_CEPH(dir, entries),
  98         XATTR_NAME_CEPH(dir, files),
  99         XATTR_NAME_CEPH(dir, subdirs),
 100         XATTR_NAME_CEPH(dir, rentries),
 101         XATTR_NAME_CEPH(dir, rfiles),
 102         XATTR_NAME_CEPH(dir, rsubdirs),
 103         XATTR_NAME_CEPH(dir, rbytes),
 104         XATTR_NAME_CEPH(dir, rctime),
 105         { 0 }   /* Required table terminator */
 106 };
 107 static size_t ceph_dir_vxattrs_name_size;       /* total size of all names */
 108
 109 /* files */
 110
 111 static size_t ceph_vxattrcb_file_layout(struct ceph_inode_info *ci, char *val,
 112                                    size_t size)
 113 {
 114         int ret;
 115
 116         ret = snprintf(val, size,
 117                 "chunk_bytes=%lld\nstripe_count=%lld\nobject_size=%lld\n",
 118                 (unsigned long long)ceph_file_layout_su(ci->i_layout),
 119                 (unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
 120                 (unsigned long long)ceph_file_layout_object_size(ci->i_layout));
 121         return ret;
 122 }
 123
 124 static struct ceph_vxattr ceph_file_vxattrs[] = {
 125         XATTR_NAME_CEPH(file, layout),
 126         /* The following extended attribute name is deprecated */
 127         {
 128                 .name = XATTR_CEPH_PREFIX "layout",
 129                 .name_size = sizeof (XATTR_CEPH_PREFIX "layout"),
 130                 .getxattr_cb = ceph_vxattrcb_file_layout,
 131                 .readonly = true,
 132         },
 133         { 0 }   /* Required table terminator */
 134 };
 135 static size_t ceph_file_vxattrs_name_size;      /* total size of all names */
 136
 137 static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
 138 {
 139         if (S_ISDIR(inode->i_mode))
 140                 return ceph_dir_vxattrs;
 141         else if (S_ISREG(inode->i_mode))
 142                 return ceph_file_vxattrs;
 143         return NULL;
 144 }
 145
 146 static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs)
 147 {
 148         if (vxattrs == ceph_dir_vxattrs)
 149                 return ceph_dir_vxattrs_name_size;
 150         if (vxattrs == ceph_file_vxattrs)
 151                 return ceph_file_vxattrs_name_size;
 152         BUG();
 153
 154         return 0;
 155 }
 156
 157 /*
 158  * Compute the aggregate size (including terminating '\0') of all
 159  * virtual extended attribute names in the given vxattr table.
 160  */
 161 static size_t __init vxattrs_name_size(struct ceph_vxattr *vxattrs)
 162 {
 163         struct ceph_vxattr *vxattr;
 164         size_t size = 0;
 165
 166         for (vxattr = vxattrs; vxattr->name; vxattr++)
 167                 size += vxattr->name_size;
 168
 169         return size;
 170 }
 171
 172 /* Routines called at initialization and exit time */
 173
 174 void __init ceph_xattr_init(void)
 175 {
 176         ceph_dir_vxattrs_name_size = vxattrs_name_size(ceph_dir_vxattrs);
 177         ceph_file_vxattrs_name_size = vxattrs_name_size(ceph_file_vxattrs);
 178 }
 179
 180 void ceph_xattr_exit(void)
 181 {
 182         ceph_dir_vxattrs_name_size = 0;
 183         ceph_file_vxattrs_name_size = 0;
 184 }
 185
 186 static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 187                                                 const char *name)
 188 {
 189         struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
 190
 191         if (vxattr) {
 192                 while (vxattr->name) {
 193                         if (!strcmp(vxattr->name, name))
 194                                 return vxattr;
 195                         vxattr++;
 196                 }
 197         }
 198
 199         return NULL;
 200 }
 201
 202 static int __set_xattr(struct ceph_inode_info *ci,
 203                            const char *name, int name_len,
 204                            const char *val, int val_len,
 205                            int dirty,
 206                            int should_free_name, int should_free_val,
 207                            struct ceph_inode_xattr **newxattr)
 208 {
 209         struct rb_node **p;
 210         struct rb_node *parent = NULL;
 211         struct ceph_inode_xattr *xattr = NULL;
 212         int c;
 213         int new = 0;
 214
 215         p = &ci->i_xattrs.index.rb_node;
 216         while (*p) {
 217                 parent = *p;
 218                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 219                 c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
 220                 if (c < 0)
 221                         p = &(*p)->rb_left;
 222                 else if (c > 0)
 223                         p = &(*p)->rb_right;
 224                 else {
 225                         if (name_len == xattr->name_len)
 226                                 break;
 227                         else if (name_len < xattr->name_len)
 228                                 p = &(*p)->rb_left;
 229                         else
 230                                 p = &(*p)->rb_right;
 231                 }
 232                 xattr = NULL;
 233         }
 234
 235         if (!xattr) {
 236                 new = 1;
 237                 xattr = *newxattr;
 238                 xattr->name = name;
 239                 xattr->name_len = name_len;
 240                 xattr->should_free_name = should_free_name;
 241
 242                 ci->i_xattrs.count++;
 243                 dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 244         } else {
 245                 kfree(*newxattr);
 246                 *newxattr = NULL;
 247                 if (xattr->should_free_val)
 248                         kfree((void *)xattr->val);
 249
 250                 if (should_free_name) {
 251                         kfree((void *)name);
 252                         name = xattr->name;
 253                 }
 254                 ci->i_xattrs.names_size -= xattr->name_len;
 255                 ci->i_xattrs.vals_size -= xattr->val_len;
 256         }
 257         ci->i_xattrs.names_size += name_len;
 258         ci->i_xattrs.vals_size += val_len;
 259         if (val)
 260                 xattr->val = val;
 261         else
 262                 xattr->val = "";
 263
 264         xattr->val_len = val_len;
 265         xattr->dirty = dirty;
 266         xattr->should_free_val = (val && should_free_val);
 267
 268         if (new) {
 269                 rb_link_node(&xattr->node, parent, p);
 270                 rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 271                 dout("__set_xattr_val p=%p\n", p);
 272         }
 273
 274         dout("__set_xattr_val added %llx.%llx xattr %p %s=%.*s\n",
 275              ceph_vinop(&ci->vfs_inode), xattr, name, val_len, val);
 276
 277         return 0;
 278 }
 279
 280 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 281                            const char *name)
 282 {
 283         struct rb_node **p;
 284         struct rb_node *parent = NULL;
 285         struct ceph_inode_xattr *xattr = NULL;
 286         int name_len = strlen(name);
 287         int c;
 288
 289         p = &ci->i_xattrs.index.rb_node;
 290         while (*p) {
 291                 parent = *p;
 292                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 293                 c = strncmp(name, xattr->name, xattr->name_len);
 294                 if (c == 0 && name_len > xattr->name_len)
 295                         c = 1;
 296                 if (c < 0)
 297                         p = &(*p)->rb_left;
 298                 else if (c > 0)
 299                         p = &(*p)->rb_right;
 300                 else {
 301                         dout("__get_xattr %s: found %.*s\n", name,
 302                              xattr->val_len, xattr->val);
 303                         return xattr;
 304                 }
 305         }
 306
 307         dout("__get_xattr %s: not found\n", name);
 308
 309         return NULL;
 310 }
 311
 312 static void __free_xattr(struct ceph_inode_xattr *xattr)
 313 {
 314         BUG_ON(!xattr);
 315
 316         if (xattr->should_free_name)
 317                 kfree((void *)xattr->name);
 318         if (xattr->should_free_val)
 319                 kfree((void *)xattr->val);
 320
 321         kfree(xattr);
 322 }
 323
 324 static int __remove_xattr(struct ceph_inode_info *ci,
 325                           struct ceph_inode_xattr *xattr)
 326 {
 327         if (!xattr)
 328                 return -EOPNOTSUPP;
 329
 330         rb_erase(&xattr->node, &ci->i_xattrs.index);
 331
 332         if (xattr->should_free_name)
 333                 kfree((void *)xattr->name);
 334         if (xattr->should_free_val)
 335                 kfree((void *)xattr->val);
 336
 337         ci->i_xattrs.names_size -= xattr->name_len;
 338         ci->i_xattrs.vals_size -= xattr->val_len;
 339         ci->i_xattrs.count--;
 340         kfree(xattr);
 341
 342         return 0;
 343 }
 344
 345 static int __remove_xattr_by_name(struct ceph_inode_info *ci,
 346                            const char *name)
 347 {
 348         struct rb_node **p;
 349         struct ceph_inode_xattr *xattr;
 350         int err;
 351
 352         p = &ci->i_xattrs.index.rb_node;
 353         xattr = __get_xattr(ci, name);
 354         err = __remove_xattr(ci, xattr);
 355         return err;
 356 }
 357
 358 static char *__copy_xattr_names(struct ceph_inode_info *ci,
 359                                 char *dest)
 360 {
 361         struct rb_node *p;
 362         struct ceph_inode_xattr *xattr = NULL;
 363
 364         p = rb_first(&ci->i_xattrs.index);
 365         dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 366
 367         while (p) {
 368                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 369                 memcpy(dest, xattr->name, xattr->name_len);
 370                 dest[xattr->name_len] = '\0';
 371
 372                 dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 373                      xattr->name_len, ci->i_xattrs.names_size);
 374
 375                 dest += xattr->name_len + 1;
 376                 p = rb_next(p);
 377         }
 378
 379         return dest;
 380 }
 381
 382 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 383 {
 384         struct rb_node *p, *tmp;
 385         struct ceph_inode_xattr *xattr = NULL;
 386
 387         p = rb_first(&ci->i_xattrs.index);
 388
 389         dout("__ceph_destroy_xattrs p=%p\n", p);
 390
 391         while (p) {
 392                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 393                 tmp = p;
 394                 p = rb_next(tmp);
 395                 dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 396                      xattr->name_len, xattr->name);
 397                 rb_erase(tmp, &ci->i_xattrs.index);
 398
 399                 __free_xattr(xattr);
 400         }
 401
 402         ci->i_xattrs.names_size = 0;
 403         ci->i_xattrs.vals_size = 0;
 404         ci->i_xattrs.index_version = 0;
 405         ci->i_xattrs.count = 0;
 406         ci->i_xattrs.index = RB_ROOT;
 407 }
 408
 409 static int __build_xattrs(struct inode *inode)
 410         __releases(ci->i_ceph_lock)
 411         __acquires(ci->i_ceph_lock)
 412 {
 413         u32 namelen;
 414         u32 numattr = 0;
 415         void *p, *end;
 416         u32 len;
 417         const char *name, *val;
 418         struct ceph_inode_info *ci = ceph_inode(inode);
 419         int xattr_version;
 420         struct ceph_inode_xattr **xattrs = NULL;
 421         int err = 0;
 422         int i;
 423
 424         dout("__build_xattrs() len=%d\n",
 425              ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 426
 427         if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 428                 return 0; /* already built */
 429
 430         __ceph_destroy_xattrs(ci);
 431
 432 start:
 433         /* updated internal xattr rb tree */
 434         if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 435                 p = ci->i_xattrs.blob->vec.iov_base;
 436                 end = p + ci->i_xattrs.blob->vec.iov_len;
 437                 ceph_decode_32_safe(&p, end, numattr, bad);
 438                 xattr_version = ci->i_xattrs.version;
 439                 spin_unlock(&ci->i_ceph_lock);
 440
 441                 xattrs = kcalloc(numattr, sizeof(struct ceph_xattr *),
 442                                  GFP_NOFS);
 443                 err = -ENOMEM;
 444                 if (!xattrs)
 445                         goto bad_lock;
 446                 memset(xattrs, 0, numattr*sizeof(struct ceph_xattr *));
 447                 for (i = 0; i < numattr; i++) {
 448                         xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 449                                             GFP_NOFS);
 450                         if (!xattrs[i])
 451                                 goto bad_lock;
 452                 }
 453
 454                 spin_lock(&ci->i_ceph_lock);
 455                 if (ci->i_xattrs.version != xattr_version) {
 456                         /* lost a race, retry */
 457                         for (i = 0; i < numattr; i++)
 458                                 kfree(xattrs[i]);
 459                         kfree(xattrs);
 460                         xattrs = NULL;
 461                         goto start;
 462                 }
 463                 err = -EIO;
 464                 while (numattr--) {
 465                         ceph_decode_32_safe(&p, end, len, bad);
 466                         namelen = len;
 467                         name = p;
 468                         p += len;
 469                         ceph_decode_32_safe(&p, end, len, bad);
 470                         val = p;
 471                         p += len;
 472
 473                         err = __set_xattr(ci, name, namelen, val, len,
 474                                           0, 0, 0, &xattrs[numattr]);
 475
 476                         if (err < 0)
 477                                 goto bad;
 478                 }
 479                 kfree(xattrs);
 480         }
 481         ci->i_xattrs.index_version = ci->i_xattrs.version;
 482         ci->i_xattrs.dirty = false;
 483
 484         return err;
 485 bad_lock:
 486         spin_lock(&ci->i_ceph_lock);
 487 bad:
 488         if (xattrs) {
 489                 for (i = 0; i < numattr; i++)
 490                         kfree(xattrs[i]);
 491                 kfree(xattrs);
 492         }
 493         ci->i_xattrs.names_size = 0;
 494         return err;
 495 }
 496
 497 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 498                                     int val_size)
 499 {
 500         /*
 501          * 4 bytes for the length, and additional 4 bytes per each xattr name,
 502          * 4 bytes per each value
 503          */
 504         int size = 4 + ci->i_xattrs.count*(4 + 4) +
 505                              ci->i_xattrs.names_size +
 506                              ci->i_xattrs.vals_size;
 507         dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 508              ci->i_xattrs.count, ci->i_xattrs.names_size,
 509              ci->i_xattrs.vals_size);
 510
 511         if (name_size)
 512                 size += 4 + 4 + name_size + val_size;
 513
 514         return size;
 515 }
 516
 517 /*
 518  * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 519  * and swap into place.
 520  */
 521 void __ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 522 {
 523         struct rb_node *p;
 524         struct ceph_inode_xattr *xattr = NULL;
 525         void *dest;
 526
 527         dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 528         if (ci->i_xattrs.dirty) {
 529                 int need = __get_required_blob_size(ci, 0, 0);
 530
 531                 BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 532
 533                 p = rb_first(&ci->i_xattrs.index);
 534                 dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 535
 536                 ceph_encode_32(&dest, ci->i_xattrs.count);
 537                 while (p) {
 538                         xattr = rb_entry(p, struct ceph_inode_xattr, node);
 539
 540                         ceph_encode_32(&dest, xattr->name_len);
 541                         memcpy(dest, xattr->name, xattr->name_len);
 542                         dest += xattr->name_len;
 543                         ceph_encode_32(&dest, xattr->val_len);
 544                         memcpy(dest, xattr->val, xattr->val_len);
 545                         dest += xattr->val_len;
 546
 547                         p = rb_next(p);
 548                 }
 549
 550                 /* adjust buffer len; it may be larger than we need */
 551                 ci->i_xattrs.prealloc_blob->vec.iov_len =
 552                         dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 553
 554                 if (ci->i_xattrs.blob)
 555                         ceph_buffer_put(ci->i_xattrs.blob);
 556                 ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 557                 ci->i_xattrs.prealloc_blob = NULL;
 558                 ci->i_xattrs.dirty = false;
 559                 ci->i_xattrs.version++;
 560         }
 561 }
 562
 563 ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
 564                       size_t size)
 565 {
 566         struct inode *inode = dentry->d_inode;
 567         struct ceph_inode_info *ci = ceph_inode(inode);
 568         int err;
 569         struct ceph_inode_xattr *xattr;
 570         struct ceph_vxattr *vxattr = NULL;
 571
 572         if (!ceph_is_valid_xattr(name))
 573                 return -ENODATA;
 574
 575         /* let's see if a virtual xattr was requested */
 576         vxattr = ceph_match_vxattr(inode, name);
 577
 578         spin_lock(&ci->i_ceph_lock);
 579         dout("getxattr %p ver=%lld index_ver=%lld\n", inode,
 580              ci->i_xattrs.version, ci->i_xattrs.index_version);
 581
 582         if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1) &&
 583             (ci->i_xattrs.index_version >= ci->i_xattrs.version)) {
 584                 goto get_xattr;
 585         } else {
 586                 spin_unlock(&ci->i_ceph_lock);
 587                 /* get xattrs from mds (if we don't already have them) */
 588                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR);
 589                 if (err)
 590                         return err;
 591         }
 592
 593         spin_lock(&ci->i_ceph_lock);
 594
 595         if (vxattr && vxattr->readonly) {
 596                 err = vxattr->getxattr_cb(ci, value, size);
 597                 goto out;
 598         }
 599
 600         err = __build_xattrs(inode);
 601         if (err < 0)
 602                 goto out;
 603
 604 get_xattr:
 605         err = -ENODATA;  /* == ENOATTR */
 606         xattr = __get_xattr(ci, name);
 607         if (!xattr) {
 608                 if (vxattr)
 609                         err = vxattr->getxattr_cb(ci, value, size);
 610                 goto out;
 611         }
 612
 613         err = -ERANGE;
 614         if (size && size < xattr->val_len)
 615                 goto out;
 616
 617         err = xattr->val_len;
 618         if (size == 0)
 619                 goto out;
 620
 621         memcpy(value, xattr->val, xattr->val_len);
 622
 623 out:
 624         spin_unlock(&ci->i_ceph_lock);
 625         return err;
 626 }
 627
 628 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 629 {
 630         struct inode *inode = dentry->d_inode;
 631         struct ceph_inode_info *ci = ceph_inode(inode);
 632         struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
 633         u32 vir_namelen = 0;
 634         u32 namelen;
 635         int err;
 636         u32 len;
 637         int i;
 638
 639         spin_lock(&ci->i_ceph_lock);
 640         dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
 641              ci->i_xattrs.version, ci->i_xattrs.index_version);
 642
 643         if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1) &&
 644             (ci->i_xattrs.index_version >= ci->i_xattrs.version)) {
 645                 goto list_xattr;
 646         } else {
 647                 spin_unlock(&ci->i_ceph_lock);
 648                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR);
 649                 if (err)
 650                         return err;
 651         }
 652
 653         spin_lock(&ci->i_ceph_lock);
 654
 655         err = __build_xattrs(inode);
 656         if (err < 0)
 657                 goto out;
 658
 659 list_xattr:
 660         /*
 661          * Start with virtual dir xattr names (if any) (including
 662          * terminating '\0' characters for each).
 663          */
 664         vir_namelen = ceph_vxattrs_name_size(vxattrs);
 665
 666         /* adding 1 byte per each variable due to the null termination */
 667         namelen = vir_namelen + ci->i_xattrs.names_size + ci->i_xattrs.count;
 668         err = -ERANGE;
 669         if (size && namelen > size)
 670                 goto out;
 671
 672         err = namelen;
 673         if (size == 0)
 674                 goto out;
 675
 676         names = __copy_xattr_names(ci, names);
 677
 678         /* virtual xattr names, too */
 679         if (vxattrs)
 680                 for (i = 0; vxattrs[i].name; i++) {
 681                         len = sprintf(names, "%s", vxattrs[i].name);
 682                         names += len + 1;
 683                 }
 684
 685 out:
 686         spin_unlock(&ci->i_ceph_lock);
 687         return err;
 688 }
 689
 690 static int ceph_sync_setxattr(struct dentry *dentry, const char *name,
 691                               const char *value, size_t size, int flags)
 692 {
 693         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 694         struct inode *inode = dentry->d_inode;
 695         struct ceph_inode_info *ci = ceph_inode(inode);
 696         struct inode *parent_inode;
 697         struct ceph_mds_request *req;
 698         struct ceph_mds_client *mdsc = fsc->mdsc;
 699         int err;
 700         int i, nr_pages;
 701         struct page **pages = NULL;
 702         void *kaddr;
 703
 704         /* copy value into some pages */
 705         nr_pages = calc_pages_for(0, size);
 706         if (nr_pages) {
 707                 pages = kmalloc(sizeof(pages[0])*nr_pages, GFP_NOFS);
 708                 if (!pages)
 709                         return -ENOMEM;
 710                 err = -ENOMEM;
 711                 for (i = 0; i < nr_pages; i++) {
 712                         pages[i] = __page_cache_alloc(GFP_NOFS);
 713                         if (!pages[i]) {
 714                                 nr_pages = i;
 715                                 goto out;
 716                         }
 717                         kaddr = kmap(pages[i]);
 718                         memcpy(kaddr, value + i*PAGE_CACHE_SIZE,
 719                                min(PAGE_CACHE_SIZE, size-i*PAGE_CACHE_SIZE));
 720                 }
 721         }
 722
 723         dout("setxattr value=%.*s\n", (int)size, value);
 724
 725         /* do request */
 726         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
 727                                        USE_AUTH_MDS);
 728         if (IS_ERR(req)) {
 729                 err = PTR_ERR(req);
 730                 goto out;
 731         }
 732         req->r_inode = inode;
 733         ihold(inode);
 734         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
 735         req->r_num_caps = 1;
 736         req->r_args.setxattr.flags = cpu_to_le32(flags);
 737         req->r_path2 = kstrdup(name, GFP_NOFS);
 738
 739         req->r_pages = pages;
 740         req->r_num_pages = nr_pages;
 741         req->r_data_len = size;
 742
 743         dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
 744         parent_inode = ceph_get_dentry_parent_inode(dentry);
 745         err = ceph_mdsc_do_request(mdsc, parent_inode, req);
 746         iput(parent_inode);
 747         ceph_mdsc_put_request(req);
 748         dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
 749
 750 out:
 751         if (pages) {
 752                 for (i = 0; i < nr_pages; i++)
 753                         __free_page(pages[i]);
 754                 kfree(pages);
 755         }
 756         return err;
 757 }
 758
 759 int ceph_setxattr(struct dentry *dentry, const char *name,
 760                   const void *value, size_t size, int flags)
 761 {
 762         struct inode *inode = dentry->d_inode;
 763         struct ceph_vxattr *vxattr;
 764         struct ceph_inode_info *ci = ceph_inode(inode);
 765         int issued;
 766         int err;
 767         int dirty;
 768         int name_len = strlen(name);
 769         int val_len = size;
 770         char *newname = NULL;
 771         char *newval = NULL;
 772         struct ceph_inode_xattr *xattr = NULL;
 773         int required_blob_size;
 774
 775         if (ceph_snap(inode) != CEPH_NOSNAP)
 776                 return -EROFS;
 777
 778         if (!ceph_is_valid_xattr(name))
 779                 return -EOPNOTSUPP;
 780
 781         vxattr = ceph_match_vxattr(inode, name);
 782         if (vxattr && vxattr->readonly)
 783                 return -EOPNOTSUPP;
 784
 785         /* preallocate memory for xattr name, value, index node */
 786         err = -ENOMEM;
 787         newname = kmemdup(name, name_len + 1, GFP_NOFS);
 788         if (!newname)
 789                 goto out;
 790
 791         if (val_len) {
 792                 newval = kmemdup(value, val_len, GFP_NOFS);
 793                 if (!newval)
 794                         goto out;
 795         }
 796
 797         xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
 798         if (!xattr)
 799                 goto out;
 800
 801         spin_lock(&ci->i_ceph_lock);
 802 retry:
 803         issued = __ceph_caps_issued(ci, NULL);
 804         dout("setxattr %p issued %s\n", inode, ceph_cap_string(issued));
 805         if (!(issued & CEPH_CAP_XATTR_EXCL))
 806                 goto do_sync;
 807         __build_xattrs(inode);
 808
 809         required_blob_size = __get_required_blob_size(ci, name_len, val_len);
 810
 811         if (!ci->i_xattrs.prealloc_blob ||
 812             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
 813                 struct ceph_buffer *blob;
 814
 815                 spin_unlock(&ci->i_ceph_lock);
 816                 dout(" preaallocating new blob size=%d\n", required_blob_size);
 817                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
 818                 if (!blob)
 819                         goto out;
 820                 spin_lock(&ci->i_ceph_lock);
 821                 if (ci->i_xattrs.prealloc_blob)
 822                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 823                 ci->i_xattrs.prealloc_blob = blob;
 824                 goto retry;
 825         }
 826
 827         err = __set_xattr(ci, newname, name_len, newval,
 828                           val_len, 1, 1, 1, &xattr);
 829
 830         dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL);
 831         ci->i_xattrs.dirty = true;
 832         inode->i_ctime = CURRENT_TIME;
 833
 834         spin_unlock(&ci->i_ceph_lock);
 835         if (dirty)
 836                 __mark_inode_dirty(inode, dirty);
 837         return err;
 838
 839 do_sync:
 840         spin_unlock(&ci->i_ceph_lock);
 841         err = ceph_sync_setxattr(dentry, name, value, size, flags);
 842 out:
 843         kfree(newname);
 844         kfree(newval);
 845         kfree(xattr);
 846         return err;
 847 }
 848
 849 static int ceph_send_removexattr(struct dentry *dentry, const char *name)
 850 {
 851         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 852         struct ceph_mds_client *mdsc = fsc->mdsc;
 853         struct inode *inode = dentry->d_inode;
 854         struct inode *parent_inode;
 855         struct ceph_mds_request *req;
 856         int err;
 857
 858         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RMXATTR,
 859                                        USE_AUTH_MDS);
 860         if (IS_ERR(req))
 861                 return PTR_ERR(req);
 862         req->r_inode = inode;
 863         ihold(inode);
 864         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
 865         req->r_num_caps = 1;
 866         req->r_path2 = kstrdup(name, GFP_NOFS);
 867
 868         parent_inode = ceph_get_dentry_parent_inode(dentry);
 869         err = ceph_mdsc_do_request(mdsc, parent_inode, req);
 870         iput(parent_inode);
 871         ceph_mdsc_put_request(req);
 872         return err;
 873 }
 874
 875 int ceph_removexattr(struct dentry *dentry, const char *name)
 876 {
 877         struct inode *inode = dentry->d_inode;
 878         struct ceph_vxattr *vxattr;
 879         struct ceph_inode_info *ci = ceph_inode(inode);
 880         int issued;
 881         int err;
 882         int required_blob_size;
 883         int dirty;
 884
 885         if (ceph_snap(inode) != CEPH_NOSNAP)
 886                 return -EROFS;
 887
 888         if (!ceph_is_valid_xattr(name))
 889                 return -EOPNOTSUPP;
 890
 891         vxattr = ceph_match_vxattr(inode, name);
 892         if (vxattr && vxattr->readonly)
 893                 return -EOPNOTSUPP;
 894
 895         err = -ENOMEM;
 896         spin_lock(&ci->i_ceph_lock);
 897 retry:
 898         issued = __ceph_caps_issued(ci, NULL);
 899         dout("removexattr %p issued %s\n", inode, ceph_cap_string(issued));
 900
 901         if (!(issued & CEPH_CAP_XATTR_EXCL))
 902                 goto do_sync;
 903         __build_xattrs(inode);
 904
 905         required_blob_size = __get_required_blob_size(ci, 0, 0);
 906
 907         if (!ci->i_xattrs.prealloc_blob ||
 908             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
 909                 struct ceph_buffer *blob;
 910
 911                 spin_unlock(&ci->i_ceph_lock);
 912                 dout(" preaallocating new blob size=%d\n", required_blob_size);
 913                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
 914                 if (!blob)
 915                         goto out;
 916                 spin_lock(&ci->i_ceph_lock);
 917                 if (ci->i_xattrs.prealloc_blob)
 918                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 919                 ci->i_xattrs.prealloc_blob = blob;
 920                 goto retry;
 921         }
 922
 923         err = __remove_xattr_by_name(ceph_inode(inode), name);
 924
 925         dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL);
 926         ci->i_xattrs.dirty = true;
 927         inode->i_ctime = CURRENT_TIME;
 928         spin_unlock(&ci->i_ceph_lock);
 929         if (dirty)
 930                 __mark_inode_dirty(inode, dirty);
 931         return err;
 932 do_sync:
 933         spin_unlock(&ci->i_ceph_lock);
 934         err = ceph_send_removexattr(dentry, name);
 935 out:
 936         return err;
 937 }
 938