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
 122         if (ceph_file_layout_pg_preferred(ci->i_layout) >= 0) {
 123                 val += ret;
 124                 size -= ret;
 125                 ret += snprintf(val, size, "preferred_osd=%lld\n",
 126                             (unsigned long long)ceph_file_layout_pg_preferred(
 127                                     ci->i_layout));
 128         }
 129
 130         return ret;
 131 }
 132
 133 static struct ceph_vxattr ceph_file_vxattrs[] = {
 134         XATTR_NAME_CEPH(file, layout),
 135         /* The following extended attribute name is deprecated */
 136         {
 137                 .name = XATTR_CEPH_PREFIX "layout",
 138                 .name_size = sizeof (XATTR_CEPH_PREFIX "layout"),
 139                 .getxattr_cb = ceph_vxattrcb_file_layout,
 140                 .readonly = true,
 141         },
 142         { 0 }   /* Required table terminator */
 143 };
 144 static size_t ceph_file_vxattrs_name_size;      /* total size of all names */
 145
 146 static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
 147 {
 148         if (S_ISDIR(inode->i_mode))
 149                 return ceph_dir_vxattrs;
 150         else if (S_ISREG(inode->i_mode))
 151                 return ceph_file_vxattrs;
 152         return NULL;
 153 }
 154
 155 static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs)
 156 {
 157         if (vxattrs == ceph_dir_vxattrs)
 158                 return ceph_dir_vxattrs_name_size;
 159         if (vxattrs == ceph_file_vxattrs)
 160                 return ceph_file_vxattrs_name_size;
 161         BUG();
 162
 163         return 0;
 164 }
 165
 166 /*
 167  * Compute the aggregate size (including terminating '\0') of all
 168  * virtual extended attribute names in the given vxattr table.
 169  */
 170 static size_t __init vxattrs_name_size(struct ceph_vxattr *vxattrs)
 171 {
 172         struct ceph_vxattr *vxattr;
 173         size_t size = 0;
 174
 175         for (vxattr = vxattrs; vxattr->name; vxattr++)
 176                 size += vxattr->name_size;
 177
 178         return size;
 179 }
 180
 181 /* Routines called at initialization and exit time */
 182
 183 void __init ceph_xattr_init(void)
 184 {
 185         ceph_dir_vxattrs_name_size = vxattrs_name_size(ceph_dir_vxattrs);
 186         ceph_file_vxattrs_name_size = vxattrs_name_size(ceph_file_vxattrs);
 187 }
 188
 189 void ceph_xattr_exit(void)
 190 {
 191         ceph_dir_vxattrs_name_size = 0;
 192         ceph_file_vxattrs_name_size = 0;
 193 }
 194
 195 static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 196                                                 const char *name)
 197 {
 198         struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
 199
 200         if (vxattr) {
 201                 while (vxattr->name) {
 202                         if (!strcmp(vxattr->name, name))
 203                                 return vxattr;
 204                         vxattr++;
 205                 }
 206         }
 207
 208         return NULL;
 209 }
 210
 211 static int __set_xattr(struct ceph_inode_info *ci,
 212                            const char *name, int name_len,
 213                            const char *val, int val_len,
 214                            int dirty,
 215                            int should_free_name, int should_free_val,
 216                            struct ceph_inode_xattr **newxattr)
 217 {
 218         struct rb_node **p;
 219         struct rb_node *parent = NULL;
 220         struct ceph_inode_xattr *xattr = NULL;
 221         int c;
 222         int new = 0;
 223
 224         p = &ci->i_xattrs.index.rb_node;
 225         while (*p) {
 226                 parent = *p;
 227                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 228                 c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
 229                 if (c < 0)
 230                         p = &(*p)->rb_left;
 231                 else if (c > 0)
 232                         p = &(*p)->rb_right;
 233                 else {
 234                         if (name_len == xattr->name_len)
 235                                 break;
 236                         else if (name_len < xattr->name_len)
 237                                 p = &(*p)->rb_left;
 238                         else
 239                                 p = &(*p)->rb_right;
 240                 }
 241                 xattr = NULL;
 242         }
 243
 244         if (!xattr) {
 245                 new = 1;
 246                 xattr = *newxattr;
 247                 xattr->name = name;
 248                 xattr->name_len = name_len;
 249                 xattr->should_free_name = should_free_name;
 250
 251                 ci->i_xattrs.count++;
 252                 dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 253         } else {
 254                 kfree(*newxattr);
 255                 *newxattr = NULL;
 256                 if (xattr->should_free_val)
 257                         kfree((void *)xattr->val);
 258
 259                 if (should_free_name) {
 260                         kfree((void *)name);
 261                         name = xattr->name;
 262                 }
 263                 ci->i_xattrs.names_size -= xattr->name_len;
 264                 ci->i_xattrs.vals_size -= xattr->val_len;
 265         }
 266         ci->i_xattrs.names_size += name_len;
 267         ci->i_xattrs.vals_size += val_len;
 268         if (val)
 269                 xattr->val = val;
 270         else
 271                 xattr->val = "";
 272
 273         xattr->val_len = val_len;
 274         xattr->dirty = dirty;
 275         xattr->should_free_val = (val && should_free_val);
 276
 277         if (new) {
 278                 rb_link_node(&xattr->node, parent, p);
 279                 rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 280                 dout("__set_xattr_val p=%p\n", p);
 281         }
 282
 283         dout("__set_xattr_val added %llx.%llx xattr %p %s=%.*s\n",
 284              ceph_vinop(&ci->vfs_inode), xattr, name, val_len, val);
 285
 286         return 0;
 287 }
 288
 289 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 290                            const char *name)
 291 {
 292         struct rb_node **p;
 293         struct rb_node *parent = NULL;
 294         struct ceph_inode_xattr *xattr = NULL;
 295         int name_len = strlen(name);
 296         int c;
 297
 298         p = &ci->i_xattrs.index.rb_node;
 299         while (*p) {
 300                 parent = *p;
 301                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 302                 c = strncmp(name, xattr->name, xattr->name_len);
 303                 if (c == 0 && name_len > xattr->name_len)
 304                         c = 1;
 305                 if (c < 0)
 306                         p = &(*p)->rb_left;
 307                 else if (c > 0)
 308                         p = &(*p)->rb_right;
 309                 else {
 310                         dout("__get_xattr %s: found %.*s\n", name,
 311                              xattr->val_len, xattr->val);
 312                         return xattr;
 313                 }
 314         }
 315
 316         dout("__get_xattr %s: not found\n", name);
 317
 318         return NULL;
 319 }
 320
 321 static void __free_xattr(struct ceph_inode_xattr *xattr)
 322 {
 323         BUG_ON(!xattr);
 324
 325         if (xattr->should_free_name)
 326                 kfree((void *)xattr->name);
 327         if (xattr->should_free_val)
 328                 kfree((void *)xattr->val);
 329
 330         kfree(xattr);
 331 }
 332
 333 static int __remove_xattr(struct ceph_inode_info *ci,
 334                           struct ceph_inode_xattr *xattr)
 335 {
 336         if (!xattr)
 337                 return -EOPNOTSUPP;
 338
 339         rb_erase(&xattr->node, &ci->i_xattrs.index);
 340
 341         if (xattr->should_free_name)
 342                 kfree((void *)xattr->name);
 343         if (xattr->should_free_val)
 344                 kfree((void *)xattr->val);
 345
 346         ci->i_xattrs.names_size -= xattr->name_len;
 347         ci->i_xattrs.vals_size -= xattr->val_len;
 348         ci->i_xattrs.count--;
 349         kfree(xattr);
 350
 351         return 0;
 352 }
 353
 354 static int __remove_xattr_by_name(struct ceph_inode_info *ci,
 355                            const char *name)
 356 {
 357         struct rb_node **p;
 358         struct ceph_inode_xattr *xattr;
 359         int err;
 360
 361         p = &ci->i_xattrs.index.rb_node;
 362         xattr = __get_xattr(ci, name);
 363         err = __remove_xattr(ci, xattr);
 364         return err;
 365 }
 366
 367 static char *__copy_xattr_names(struct ceph_inode_info *ci,
 368                                 char *dest)
 369 {
 370         struct rb_node *p;
 371         struct ceph_inode_xattr *xattr = NULL;
 372
 373         p = rb_first(&ci->i_xattrs.index);
 374         dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 375
 376         while (p) {
 377                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 378                 memcpy(dest, xattr->name, xattr->name_len);
 379                 dest[xattr->name_len] = '\0';
 380
 381                 dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 382                      xattr->name_len, ci->i_xattrs.names_size);
 383
 384                 dest += xattr->name_len + 1;
 385                 p = rb_next(p);
 386         }
 387
 388         return dest;
 389 }
 390
 391 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 392 {
 393         struct rb_node *p, *tmp;
 394         struct ceph_inode_xattr *xattr = NULL;
 395
 396         p = rb_first(&ci->i_xattrs.index);
 397
 398         dout("__ceph_destroy_xattrs p=%p\n", p);
 399
 400         while (p) {
 401                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 402                 tmp = p;
 403                 p = rb_next(tmp);
 404                 dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 405                      xattr->name_len, xattr->name);
 406                 rb_erase(tmp, &ci->i_xattrs.index);
 407
 408                 __free_xattr(xattr);
 409         }
 410
 411         ci->i_xattrs.names_size = 0;
 412         ci->i_xattrs.vals_size = 0;
 413         ci->i_xattrs.index_version = 0;
 414         ci->i_xattrs.count = 0;
 415         ci->i_xattrs.index = RB_ROOT;
 416 }
 417
 418 static int __build_xattrs(struct inode *inode)
 419         __releases(ci->i_ceph_lock)
 420         __acquires(ci->i_ceph_lock)
 421 {
 422         u32 namelen;
 423         u32 numattr = 0;
 424         void *p, *end;
 425         u32 len;
 426         const char *name, *val;
 427         struct ceph_inode_info *ci = ceph_inode(inode);
 428         int xattr_version;
 429         struct ceph_inode_xattr **xattrs = NULL;
 430         int err = 0;
 431         int i;
 432
 433         dout("__build_xattrs() len=%d\n",
 434              ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 435
 436         if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 437                 return 0; /* already built */
 438
 439         __ceph_destroy_xattrs(ci);
 440
 441 start:
 442         /* updated internal xattr rb tree */
 443         if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 444                 p = ci->i_xattrs.blob->vec.iov_base;
 445                 end = p + ci->i_xattrs.blob->vec.iov_len;
 446                 ceph_decode_32_safe(&p, end, numattr, bad);
 447                 xattr_version = ci->i_xattrs.version;
 448                 spin_unlock(&ci->i_ceph_lock);
 449
 450                 xattrs = kcalloc(numattr, sizeof(struct ceph_xattr *),
 451                                  GFP_NOFS);
 452                 err = -ENOMEM;
 453                 if (!xattrs)
 454                         goto bad_lock;
 455                 memset(xattrs, 0, numattr*sizeof(struct ceph_xattr *));
 456                 for (i = 0; i < numattr; i++) {
 457                         xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 458                                             GFP_NOFS);
 459                         if (!xattrs[i])
 460                                 goto bad_lock;
 461                 }
 462
 463                 spin_lock(&ci->i_ceph_lock);
 464                 if (ci->i_xattrs.version != xattr_version) {
 465                         /* lost a race, retry */
 466                         for (i = 0; i < numattr; i++)
 467                                 kfree(xattrs[i]);
 468                         kfree(xattrs);
 469                         goto start;
 470                 }
 471                 err = -EIO;
 472                 while (numattr--) {
 473                         ceph_decode_32_safe(&p, end, len, bad);
 474                         namelen = len;
 475                         name = p;
 476                         p += len;
 477                         ceph_decode_32_safe(&p, end, len, bad);
 478                         val = p;
 479                         p += len;
 480
 481                         err = __set_xattr(ci, name, namelen, val, len,
 482                                           0, 0, 0, &xattrs[numattr]);
 483
 484                         if (err < 0)
 485                                 goto bad;
 486                 }
 487                 kfree(xattrs);
 488         }
 489         ci->i_xattrs.index_version = ci->i_xattrs.version;
 490         ci->i_xattrs.dirty = false;
 491
 492         return err;
 493 bad_lock:
 494         spin_lock(&ci->i_ceph_lock);
 495 bad:
 496         if (xattrs) {
 497                 for (i = 0; i < numattr; i++)
 498                         kfree(xattrs[i]);
 499                 kfree(xattrs);
 500         }
 501         ci->i_xattrs.names_size = 0;
 502         return err;
 503 }
 504
 505 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 506                                     int val_size)
 507 {
 508         /*
 509          * 4 bytes for the length, and additional 4 bytes per each xattr name,
 510          * 4 bytes per each value
 511          */
 512         int size = 4 + ci->i_xattrs.count*(4 + 4) +
 513                              ci->i_xattrs.names_size +
 514                              ci->i_xattrs.vals_size;
 515         dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 516              ci->i_xattrs.count, ci->i_xattrs.names_size,
 517              ci->i_xattrs.vals_size);
 518
 519         if (name_size)
 520                 size += 4 + 4 + name_size + val_size;
 521
 522         return size;
 523 }
 524
 525 /*
 526  * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 527  * and swap into place.
 528  */
 529 void __ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 530 {
 531         struct rb_node *p;
 532         struct ceph_inode_xattr *xattr = NULL;
 533         void *dest;
 534
 535         dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 536         if (ci->i_xattrs.dirty) {
 537                 int need = __get_required_blob_size(ci, 0, 0);
 538
 539                 BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 540
 541                 p = rb_first(&ci->i_xattrs.index);
 542                 dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 543
 544                 ceph_encode_32(&dest, ci->i_xattrs.count);
 545                 while (p) {
 546                         xattr = rb_entry(p, struct ceph_inode_xattr, node);
 547
 548                         ceph_encode_32(&dest, xattr->name_len);
 549                         memcpy(dest, xattr->name, xattr->name_len);
 550                         dest += xattr->name_len;
 551                         ceph_encode_32(&dest, xattr->val_len);
 552                         memcpy(dest, xattr->val, xattr->val_len);
 553                         dest += xattr->val_len;
 554
 555                         p = rb_next(p);
 556                 }
 557
 558                 /* adjust buffer len; it may be larger than we need */
 559                 ci->i_xattrs.prealloc_blob->vec.iov_len =
 560                         dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 561
 562                 if (ci->i_xattrs.blob)
 563                         ceph_buffer_put(ci->i_xattrs.blob);
 564                 ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 565                 ci->i_xattrs.prealloc_blob = NULL;
 566                 ci->i_xattrs.dirty = false;
 567                 ci->i_xattrs.version++;
 568         }
 569 }
 570
 571 ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
 572                       size_t size)
 573 {
 574         struct inode *inode = dentry->d_inode;
 575         struct ceph_inode_info *ci = ceph_inode(inode);
 576         int err;
 577         struct ceph_inode_xattr *xattr;
 578         struct ceph_vxattr *vxattr = NULL;
 579
 580         if (!ceph_is_valid_xattr(name))
 581                 return -ENODATA;
 582
 583         /* let's see if a virtual xattr was requested */
 584         vxattr = ceph_match_vxattr(inode, name);
 585
 586         spin_lock(&ci->i_ceph_lock);
 587         dout("getxattr %p ver=%lld index_ver=%lld\n", inode,
 588              ci->i_xattrs.version, ci->i_xattrs.index_version);
 589
 590         if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1) &&
 591             (ci->i_xattrs.index_version >= ci->i_xattrs.version)) {
 592                 goto get_xattr;
 593         } else {
 594                 spin_unlock(&ci->i_ceph_lock);
 595                 /* get xattrs from mds (if we don't already have them) */
 596                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR);
 597                 if (err)
 598                         return err;
 599         }
 600
 601         spin_lock(&ci->i_ceph_lock);
 602
 603         if (vxattr && vxattr->readonly) {
 604                 err = vxattr->getxattr_cb(ci, value, size);
 605                 goto out;
 606         }
 607
 608         err = __build_xattrs(inode);
 609         if (err < 0)
 610                 goto out;
 611
 612 get_xattr:
 613         err = -ENODATA;  /* == ENOATTR */
 614         xattr = __get_xattr(ci, name);
 615         if (!xattr) {
 616                 if (vxattr)
 617                         err = vxattr->getxattr_cb(ci, value, size);
 618                 goto out;
 619         }
 620
 621         err = -ERANGE;
 622         if (size && size < xattr->val_len)
 623                 goto out;
 624
 625         err = xattr->val_len;
 626         if (size == 0)
 627                 goto out;
 628
 629         memcpy(value, xattr->val, xattr->val_len);
 630
 631 out:
 632         spin_unlock(&ci->i_ceph_lock);
 633         return err;
 634 }
 635
 636 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 637 {
 638         struct inode *inode = dentry->d_inode;
 639         struct ceph_inode_info *ci = ceph_inode(inode);
 640         struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
 641         u32 vir_namelen = 0;
 642         u32 namelen;
 643         int err;
 644         u32 len;
 645         int i;
 646
 647         spin_lock(&ci->i_ceph_lock);
 648         dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
 649              ci->i_xattrs.version, ci->i_xattrs.index_version);
 650
 651         if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1) &&
 652             (ci->i_xattrs.index_version >= ci->i_xattrs.version)) {
 653                 goto list_xattr;
 654         } else {
 655                 spin_unlock(&ci->i_ceph_lock);
 656                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR);
 657                 if (err)
 658                         return err;
 659         }
 660
 661         spin_lock(&ci->i_ceph_lock);
 662
 663         err = __build_xattrs(inode);
 664         if (err < 0)
 665                 goto out;
 666
 667 list_xattr:
 668         /*
 669          * Start with virtual dir xattr names (if any) (including
 670          * terminating '\0' characters for each).
 671          */
 672         vir_namelen = ceph_vxattrs_name_size(vxattrs);
 673
 674         /* adding 1 byte per each variable due to the null termination */
 675         namelen = vir_namelen + ci->i_xattrs.names_size + ci->i_xattrs.count;
 676         err = -ERANGE;
 677         if (size && namelen > size)
 678                 goto out;
 679
 680         err = namelen;
 681         if (size == 0)
 682                 goto out;
 683
 684         names = __copy_xattr_names(ci, names);
 685
 686         /* virtual xattr names, too */
 687         if (vxattrs)
 688                 for (i = 0; vxattrs[i].name; i++) {
 689                         len = sprintf(names, "%s", vxattrs[i].name);
 690                         names += len + 1;
 691                 }
 692
 693 out:
 694         spin_unlock(&ci->i_ceph_lock);
 695         return err;
 696 }
 697
 698 static int ceph_sync_setxattr(struct dentry *dentry, const char *name,
 699                               const char *value, size_t size, int flags)
 700 {
 701         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 702         struct inode *inode = dentry->d_inode;
 703         struct ceph_inode_info *ci = ceph_inode(inode);
 704         struct inode *parent_inode;
 705         struct ceph_mds_request *req;
 706         struct ceph_mds_client *mdsc = fsc->mdsc;
 707         int err;
 708         int i, nr_pages;
 709         struct page **pages = NULL;
 710         void *kaddr;
 711
 712         /* copy value into some pages */
 713         nr_pages = calc_pages_for(0, size);
 714         if (nr_pages) {
 715                 pages = kmalloc(sizeof(pages[0])*nr_pages, GFP_NOFS);
 716                 if (!pages)
 717                         return -ENOMEM;
 718                 err = -ENOMEM;
 719                 for (i = 0; i < nr_pages; i++) {
 720                         pages[i] = __page_cache_alloc(GFP_NOFS);
 721                         if (!pages[i]) {
 722                                 nr_pages = i;
 723                                 goto out;
 724                         }
 725                         kaddr = kmap(pages[i]);
 726                         memcpy(kaddr, value + i*PAGE_CACHE_SIZE,
 727                                min(PAGE_CACHE_SIZE, size-i*PAGE_CACHE_SIZE));
 728                 }
 729         }
 730
 731         dout("setxattr value=%.*s\n", (int)size, value);
 732
 733         /* do request */
 734         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
 735                                        USE_AUTH_MDS);
 736         if (IS_ERR(req)) {
 737                 err = PTR_ERR(req);
 738                 goto out;
 739         }
 740         req->r_inode = inode;
 741         ihold(inode);
 742         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
 743         req->r_num_caps = 1;
 744         req->r_args.setxattr.flags = cpu_to_le32(flags);
 745         req->r_path2 = kstrdup(name, GFP_NOFS);
 746
 747         req->r_pages = pages;
 748         req->r_num_pages = nr_pages;
 749         req->r_data_len = size;
 750
 751         dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
 752         parent_inode = ceph_get_dentry_parent_inode(dentry);
 753         err = ceph_mdsc_do_request(mdsc, parent_inode, req);
 754         iput(parent_inode);
 755         ceph_mdsc_put_request(req);
 756         dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
 757
 758 out:
 759         if (pages) {
 760                 for (i = 0; i < nr_pages; i++)
 761                         __free_page(pages[i]);
 762                 kfree(pages);
 763         }
 764         return err;
 765 }
 766
 767 int ceph_setxattr(struct dentry *dentry, const char *name,
 768                   const void *value, size_t size, int flags)
 769 {
 770         struct inode *inode = dentry->d_inode;
 771         struct ceph_vxattr *vxattr;
 772         struct ceph_inode_info *ci = ceph_inode(inode);
 773         int issued;
 774         int err;
 775         int dirty;
 776         int name_len = strlen(name);
 777         int val_len = size;
 778         char *newname = NULL;
 779         char *newval = NULL;
 780         struct ceph_inode_xattr *xattr = NULL;
 781         int required_blob_size;
 782
 783         if (ceph_snap(inode) != CEPH_NOSNAP)
 784                 return -EROFS;
 785
 786         if (!ceph_is_valid_xattr(name))
 787                 return -EOPNOTSUPP;
 788
 789         vxattr = ceph_match_vxattr(inode, name);
 790         if (vxattr && vxattr->readonly)
 791                 return -EOPNOTSUPP;
 792
 793         /* preallocate memory for xattr name, value, index node */
 794         err = -ENOMEM;
 795         newname = kmemdup(name, name_len + 1, GFP_NOFS);
 796         if (!newname)
 797                 goto out;
 798
 799         if (val_len) {
 800                 newval = kmemdup(value, val_len, GFP_NOFS);
 801                 if (!newval)
 802                         goto out;
 803         }
 804
 805         xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
 806         if (!xattr)
 807                 goto out;
 808
 809         spin_lock(&ci->i_ceph_lock);
 810 retry:
 811         issued = __ceph_caps_issued(ci, NULL);
 812         dout("setxattr %p issued %s\n", inode, ceph_cap_string(issued));
 813         if (!(issued & CEPH_CAP_XATTR_EXCL))
 814                 goto do_sync;
 815         __build_xattrs(inode);
 816
 817         required_blob_size = __get_required_blob_size(ci, name_len, val_len);
 818
 819         if (!ci->i_xattrs.prealloc_blob ||
 820             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
 821                 struct ceph_buffer *blob;
 822
 823                 spin_unlock(&ci->i_ceph_lock);
 824                 dout(" preaallocating new blob size=%d\n", required_blob_size);
 825                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
 826                 if (!blob)
 827                         goto out;
 828                 spin_lock(&ci->i_ceph_lock);
 829                 if (ci->i_xattrs.prealloc_blob)
 830                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 831                 ci->i_xattrs.prealloc_blob = blob;
 832                 goto retry;
 833         }
 834
 835         err = __set_xattr(ci, newname, name_len, newval,
 836                           val_len, 1, 1, 1, &xattr);
 837
 838         dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL);
 839         ci->i_xattrs.dirty = true;
 840         inode->i_ctime = CURRENT_TIME;
 841
 842         spin_unlock(&ci->i_ceph_lock);
 843         if (dirty)
 844                 __mark_inode_dirty(inode, dirty);
 845         return err;
 846
 847 do_sync:
 848         spin_unlock(&ci->i_ceph_lock);
 849         err = ceph_sync_setxattr(dentry, name, value, size, flags);
 850 out:
 851         kfree(newname);
 852         kfree(newval);
 853         kfree(xattr);
 854         return err;
 855 }
 856
 857 static int ceph_send_removexattr(struct dentry *dentry, const char *name)
 858 {
 859         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 860         struct ceph_mds_client *mdsc = fsc->mdsc;
 861         struct inode *inode = dentry->d_inode;
 862         struct inode *parent_inode;
 863         struct ceph_mds_request *req;
 864         int err;
 865
 866         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RMXATTR,
 867                                        USE_AUTH_MDS);
 868         if (IS_ERR(req))
 869                 return PTR_ERR(req);
 870         req->r_inode = inode;
 871         ihold(inode);
 872         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
 873         req->r_num_caps = 1;
 874         req->r_path2 = kstrdup(name, GFP_NOFS);
 875
 876         parent_inode = ceph_get_dentry_parent_inode(dentry);
 877         err = ceph_mdsc_do_request(mdsc, parent_inode, req);
 878         iput(parent_inode);
 879         ceph_mdsc_put_request(req);
 880         return err;
 881 }
 882
 883 int ceph_removexattr(struct dentry *dentry, const char *name)
 884 {
 885         struct inode *inode = dentry->d_inode;
 886         struct ceph_vxattr *vxattr;
 887         struct ceph_inode_info *ci = ceph_inode(inode);
 888         int issued;
 889         int err;
 890         int required_blob_size;
 891         int dirty;
 892
 893         if (ceph_snap(inode) != CEPH_NOSNAP)
 894                 return -EROFS;
 895
 896         if (!ceph_is_valid_xattr(name))
 897                 return -EOPNOTSUPP;
 898
 899         vxattr = ceph_match_vxattr(inode, name);
 900         if (vxattr && vxattr->readonly)
 901                 return -EOPNOTSUPP;
 902
 903         err = -ENOMEM;
 904         spin_lock(&ci->i_ceph_lock);
 905 retry:
 906         issued = __ceph_caps_issued(ci, NULL);
 907         dout("removexattr %p issued %s\n", inode, ceph_cap_string(issued));
 908
 909         if (!(issued & CEPH_CAP_XATTR_EXCL))
 910                 goto do_sync;
 911         __build_xattrs(inode);
 912
 913         required_blob_size = __get_required_blob_size(ci, 0, 0);
 914
 915         if (!ci->i_xattrs.prealloc_blob ||
 916             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
 917                 struct ceph_buffer *blob;
 918
 919                 spin_unlock(&ci->i_ceph_lock);
 920                 dout(" preaallocating new blob size=%d\n", required_blob_size);
 921                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
 922                 if (!blob)
 923                         goto out;
 924                 spin_lock(&ci->i_ceph_lock);
 925                 if (ci->i_xattrs.prealloc_blob)
 926                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 927                 ci->i_xattrs.prealloc_blob = blob;
 928                 goto retry;
 929         }
 930
 931         err = __remove_xattr_by_name(ceph_inode(inode), name);
 932
 933         dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL);
 934         ci->i_xattrs.dirty = true;
 935         inode->i_ctime = CURRENT_TIME;
 936         spin_unlock(&ci->i_ceph_lock);
 937         if (dirty)
 938                 __mark_inode_dirty(inode, dirty);
 939         return err;
 940 do_sync:
 941         spin_unlock(&ci->i_ceph_lock);
 942         err = ceph_send_removexattr(dentry, name);
 943 out:
 944         return err;
 945 }
 946