fs/ceph/xattr.c

   1 #include <linux/ceph/ceph_debug.h>
   2 #include <linux/ceph/pagelist.h>
   3
   4 #include "super.h"
   5 #include "mds_client.h"
   6
   7 #include <linux/ceph/decode.h>
   8
   9 #include <linux/xattr.h>
  10 #include <linux/posix_acl_xattr.h>
  11 #include <linux/slab.h>
  12
  13 #define XATTR_CEPH_PREFIX "ceph."
  14 #define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)
  15
  16 static int __remove_xattr(struct ceph_inode_info *ci,
  17                           struct ceph_inode_xattr *xattr);
  18
  19 /*
  20  * List of handlers for synthetic system.* attributes. Other
  21  * attributes are handled directly.
  22  */
  23 const struct xattr_handler *ceph_xattr_handlers[] = {
  24 #ifdef CONFIG_CEPH_FS_POSIX_ACL
  25         &posix_acl_access_xattr_handler,
  26         &posix_acl_default_xattr_handler,
  27 #endif
  28         NULL,
  29 };
  30
  31 static bool ceph_is_valid_xattr(const char *name)
  32 {
  33         return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
  34                !strncmp(name, XATTR_SECURITY_PREFIX,
  35                         XATTR_SECURITY_PREFIX_LEN) ||
  36                !strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) ||
  37                !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
  38                !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
  39 }
  40
  41 /*
  42  * These define virtual xattrs exposing the recursive directory
  43  * statistics and layout metadata.
  44  */
  45 struct ceph_vxattr {
  46         char *name;
  47         size_t name_size;       /* strlen(name) + 1 (for '\0') */
  48         size_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
  49                               size_t size);
  50         bool readonly, hidden;
  51         bool (*exists_cb)(struct ceph_inode_info *ci);
  52 };
  53
  54 /* layouts */
  55
  56 static bool ceph_vxattrcb_layout_exists(struct ceph_inode_info *ci)
  57 {
  58         size_t s;
  59         char *p = (char *)&ci->i_layout;
  60
  61         for (s = 0; s < sizeof(ci->i_layout); s++, p++)
  62                 if (*p)
  63                         return true;
  64         return false;
  65 }
  66
  67 static size_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
  68                                    size_t size)
  69 {
  70         int ret;
  71         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
  72         struct ceph_osd_client *osdc = &fsc->client->osdc;
  73         s64 pool = ceph_file_layout_pg_pool(ci->i_layout);
  74         const char *pool_name;
  75         char buf[128];
  76
  77         dout("ceph_vxattrcb_layout %p\n", &ci->vfs_inode);
  78         down_read(&osdc->map_sem);
  79         pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
  80         if (pool_name) {
  81                 size_t len = strlen(pool_name);
  82                 ret = snprintf(buf, sizeof(buf),
  83                 "stripe_unit=%lld stripe_count=%lld object_size=%lld pool=",
  84                 (unsigned long long)ceph_file_layout_su(ci->i_layout),
  85                 (unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
  86                 (unsigned long long)ceph_file_layout_object_size(ci->i_layout));
  87                 if (!size) {
  88                         ret += len;
  89                 } else if (ret + len > size) {
  90                         ret = -ERANGE;
  91                 } else {
  92                         memcpy(val, buf, ret);
  93                         memcpy(val + ret, pool_name, len);
  94                         ret += len;
  95                 }
  96         } else {
  97                 ret = snprintf(buf, sizeof(buf),
  98                 "stripe_unit=%lld stripe_count=%lld object_size=%lld pool=%lld",
  99                 (unsigned long long)ceph_file_layout_su(ci->i_layout),
 100                 (unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
 101                 (unsigned long long)ceph_file_layout_object_size(ci->i_layout),
 102                 (unsigned long long)pool);
 103                 if (size) {
 104                         if (ret <= size)
 105                                 memcpy(val, buf, ret);
 106                         else
 107                                 ret = -ERANGE;
 108                 }
 109         }
 110         up_read(&osdc->map_sem);
 111         return ret;
 112 }
 113
 114 static size_t ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info *ci,
 115                                                char *val, size_t size)
 116 {
 117         return snprintf(val, size, "%lld",
 118                         (unsigned long long)ceph_file_layout_su(ci->i_layout));
 119 }
 120
 121 static size_t ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info *ci,
 122                                                 char *val, size_t size)
 123 {
 124         return snprintf(val, size, "%lld",
 125                (unsigned long long)ceph_file_layout_stripe_count(ci->i_layout));
 126 }
 127
 128 static size_t ceph_vxattrcb_layout_object_size(struct ceph_inode_info *ci,
 129                                                char *val, size_t size)
 130 {
 131         return snprintf(val, size, "%lld",
 132                (unsigned long long)ceph_file_layout_object_size(ci->i_layout));
 133 }
 134
 135 static size_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
 136                                         char *val, size_t size)
 137 {
 138         int ret;
 139         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
 140         struct ceph_osd_client *osdc = &fsc->client->osdc;
 141         s64 pool = ceph_file_layout_pg_pool(ci->i_layout);
 142         const char *pool_name;
 143
 144         down_read(&osdc->map_sem);
 145         pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
 146         if (pool_name)
 147                 ret = snprintf(val, size, "%s", pool_name);
 148         else
 149                 ret = snprintf(val, size, "%lld", (unsigned long long)pool);
 150         up_read(&osdc->map_sem);
 151         return ret;
 152 }
 153
 154 /* directories */
 155
 156 static size_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
 157                                         size_t size)
 158 {
 159         return snprintf(val, size, "%lld", ci->i_files + ci->i_subdirs);
 160 }
 161
 162 static size_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
 163                                       size_t size)
 164 {
 165         return snprintf(val, size, "%lld", ci->i_files);
 166 }
 167
 168 static size_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
 169                                         size_t size)
 170 {
 171         return snprintf(val, size, "%lld", ci->i_subdirs);
 172 }
 173
 174 static size_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
 175                                          size_t size)
 176 {
 177         return snprintf(val, size, "%lld", ci->i_rfiles + ci->i_rsubdirs);
 178 }
 179
 180 static size_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
 181                                        size_t size)
 182 {
 183         return snprintf(val, size, "%lld", ci->i_rfiles);
 184 }
 185
 186 static size_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
 187                                          size_t size)
 188 {
 189         return snprintf(val, size, "%lld", ci->i_rsubdirs);
 190 }
 191
 192 static size_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
 193                                        size_t size)
 194 {
 195         return snprintf(val, size, "%lld", ci->i_rbytes);
 196 }
 197
 198 static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
 199                                        size_t size)
 200 {
 201         return snprintf(val, size, "%ld.09%ld", (long)ci->i_rctime.tv_sec,
 202                         (long)ci->i_rctime.tv_nsec);
 203 }
 204
 205
 206 #define CEPH_XATTR_NAME(_type, _name)   XATTR_CEPH_PREFIX #_type "." #_name
 207 #define CEPH_XATTR_NAME2(_type, _name, _name2)  \
 208         XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
 209
 210 #define XATTR_NAME_CEPH(_type, _name)                                   \
 211         {                                                               \
 212                 .name = CEPH_XATTR_NAME(_type, _name),                  \
 213                 .name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
 214                 .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
 215                 .readonly = true,                               \
 216                 .hidden = false,                                \
 217                 .exists_cb = NULL,                      \
 218         }
 219 #define XATTR_LAYOUT_FIELD(_type, _name, _field)                        \
 220         {                                                               \
 221                 .name = CEPH_XATTR_NAME2(_type, _name, _field), \
 222                 .name_size = sizeof (CEPH_XATTR_NAME2(_type, _name, _field)), \
 223                 .getxattr_cb = ceph_vxattrcb_ ## _name ## _ ## _field, \
 224                 .readonly = false,                              \
 225                 .hidden = true,                 \
 226                 .exists_cb = ceph_vxattrcb_layout_exists,       \
 227         }
 228
 229 static struct ceph_vxattr ceph_dir_vxattrs[] = {
 230         {
 231                 .name = "ceph.dir.layout",
 232                 .name_size = sizeof("ceph.dir.layout"),
 233                 .getxattr_cb = ceph_vxattrcb_layout,
 234                 .readonly = false,
 235                 .hidden = true,
 236                 .exists_cb = ceph_vxattrcb_layout_exists,
 237         },
 238         XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
 239         XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
 240         XATTR_LAYOUT_FIELD(dir, layout, object_size),
 241         XATTR_LAYOUT_FIELD(dir, layout, pool),
 242         XATTR_NAME_CEPH(dir, entries),
 243         XATTR_NAME_CEPH(dir, files),
 244         XATTR_NAME_CEPH(dir, subdirs),
 245         XATTR_NAME_CEPH(dir, rentries),
 246         XATTR_NAME_CEPH(dir, rfiles),
 247         XATTR_NAME_CEPH(dir, rsubdirs),
 248         XATTR_NAME_CEPH(dir, rbytes),
 249         XATTR_NAME_CEPH(dir, rctime),
 250         { .name = NULL, 0 }     /* Required table terminator */
 251 };
 252 static size_t ceph_dir_vxattrs_name_size;       /* total size of all names */
 253
 254 /* files */
 255
 256 static struct ceph_vxattr ceph_file_vxattrs[] = {
 257         {
 258                 .name = "ceph.file.layout",
 259                 .name_size = sizeof("ceph.file.layout"),
 260                 .getxattr_cb = ceph_vxattrcb_layout,
 261                 .readonly = false,
 262                 .hidden = true,
 263                 .exists_cb = ceph_vxattrcb_layout_exists,
 264         },
 265         XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
 266         XATTR_LAYOUT_FIELD(file, layout, stripe_count),
 267         XATTR_LAYOUT_FIELD(file, layout, object_size),
 268         XATTR_LAYOUT_FIELD(file, layout, pool),
 269         { .name = NULL, 0 }     /* Required table terminator */
 270 };
 271 static size_t ceph_file_vxattrs_name_size;      /* total size of all names */
 272
 273 static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
 274 {
 275         if (S_ISDIR(inode->i_mode))
 276                 return ceph_dir_vxattrs;
 277         else if (S_ISREG(inode->i_mode))
 278                 return ceph_file_vxattrs;
 279         return NULL;
 280 }
 281
 282 static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs)
 283 {
 284         if (vxattrs == ceph_dir_vxattrs)
 285                 return ceph_dir_vxattrs_name_size;
 286         if (vxattrs == ceph_file_vxattrs)
 287                 return ceph_file_vxattrs_name_size;
 288         BUG_ON(vxattrs);
 289         return 0;
 290 }
 291
 292 /*
 293  * Compute the aggregate size (including terminating '\0') of all
 294  * virtual extended attribute names in the given vxattr table.
 295  */
 296 static size_t __init vxattrs_name_size(struct ceph_vxattr *vxattrs)
 297 {
 298         struct ceph_vxattr *vxattr;
 299         size_t size = 0;
 300
 301         for (vxattr = vxattrs; vxattr->name; vxattr++)
 302                 if (!vxattr->hidden)
 303                         size += vxattr->name_size;
 304
 305         return size;
 306 }
 307
 308 /* Routines called at initialization and exit time */
 309
 310 void __init ceph_xattr_init(void)
 311 {
 312         ceph_dir_vxattrs_name_size = vxattrs_name_size(ceph_dir_vxattrs);
 313         ceph_file_vxattrs_name_size = vxattrs_name_size(ceph_file_vxattrs);
 314 }
 315
 316 void ceph_xattr_exit(void)
 317 {
 318         ceph_dir_vxattrs_name_size = 0;
 319         ceph_file_vxattrs_name_size = 0;
 320 }
 321
 322 static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 323                                                 const char *name)
 324 {
 325         struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
 326
 327         if (vxattr) {
 328                 while (vxattr->name) {
 329                         if (!strcmp(vxattr->name, name))
 330                                 return vxattr;
 331                         vxattr++;
 332                 }
 333         }
 334
 335         return NULL;
 336 }
 337
 338 static int __set_xattr(struct ceph_inode_info *ci,
 339                            const char *name, int name_len,
 340                            const char *val, int val_len,
 341                            int flags, int update_xattr,
 342                            struct ceph_inode_xattr **newxattr)
 343 {
 344         struct rb_node **p;
 345         struct rb_node *parent = NULL;
 346         struct ceph_inode_xattr *xattr = NULL;
 347         int c;
 348         int new = 0;
 349
 350         p = &ci->i_xattrs.index.rb_node;
 351         while (*p) {
 352                 parent = *p;
 353                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 354                 c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
 355                 if (c < 0)
 356                         p = &(*p)->rb_left;
 357                 else if (c > 0)
 358                         p = &(*p)->rb_right;
 359                 else {
 360                         if (name_len == xattr->name_len)
 361                                 break;
 362                         else if (name_len < xattr->name_len)
 363                                 p = &(*p)->rb_left;
 364                         else
 365                                 p = &(*p)->rb_right;
 366                 }
 367                 xattr = NULL;
 368         }
 369
 370         if (update_xattr) {
 371                 int err = 0;
 372                 if (xattr && (flags & XATTR_CREATE))
 373                         err = -EEXIST;
 374                 else if (!xattr && (flags & XATTR_REPLACE))
 375                         err = -ENODATA;
 376                 if (err) {
 377                         kfree(name);
 378                         kfree(val);
 379                         return err;
 380                 }
 381                 if (update_xattr < 0) {
 382                         if (xattr)
 383                                 __remove_xattr(ci, xattr);
 384                         kfree(name);
 385                         return 0;
 386                 }
 387         }
 388
 389         if (!xattr) {
 390                 new = 1;
 391                 xattr = *newxattr;
 392                 xattr->name = name;
 393                 xattr->name_len = name_len;
 394                 xattr->should_free_name = update_xattr;
 395
 396                 ci->i_xattrs.count++;
 397                 dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 398         } else {
 399                 kfree(*newxattr);
 400                 *newxattr = NULL;
 401                 if (xattr->should_free_val)
 402                         kfree((void *)xattr->val);
 403
 404                 if (update_xattr) {
 405                         kfree((void *)name);
 406                         name = xattr->name;
 407                 }
 408                 ci->i_xattrs.names_size -= xattr->name_len;
 409                 ci->i_xattrs.vals_size -= xattr->val_len;
 410         }
 411         ci->i_xattrs.names_size += name_len;
 412         ci->i_xattrs.vals_size += val_len;
 413         if (val)
 414                 xattr->val = val;
 415         else
 416                 xattr->val = "";
 417
 418         xattr->val_len = val_len;
 419         xattr->dirty = update_xattr;
 420         xattr->should_free_val = (val && update_xattr);
 421
 422         if (new) {
 423                 rb_link_node(&xattr->node, parent, p);
 424                 rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 425                 dout("__set_xattr_val p=%p\n", p);
 426         }
 427
 428         dout("__set_xattr_val added %llx.%llx xattr %p %s=%.*s\n",
 429              ceph_vinop(&ci->vfs_inode), xattr, name, val_len, val);
 430
 431         return 0;
 432 }
 433
 434 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 435                            const char *name)
 436 {
 437         struct rb_node **p;
 438         struct rb_node *parent = NULL;
 439         struct ceph_inode_xattr *xattr = NULL;
 440         int name_len = strlen(name);
 441         int c;
 442
 443         p = &ci->i_xattrs.index.rb_node;
 444         while (*p) {
 445                 parent = *p;
 446                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 447                 c = strncmp(name, xattr->name, xattr->name_len);
 448                 if (c == 0 && name_len > xattr->name_len)
 449                         c = 1;
 450                 if (c < 0)
 451                         p = &(*p)->rb_left;
 452                 else if (c > 0)
 453                         p = &(*p)->rb_right;
 454                 else {
 455                         dout("__get_xattr %s: found %.*s\n", name,
 456                              xattr->val_len, xattr->val);
 457                         return xattr;
 458                 }
 459         }
 460
 461         dout("__get_xattr %s: not found\n", name);
 462
 463         return NULL;
 464 }
 465
 466 static void __free_xattr(struct ceph_inode_xattr *xattr)
 467 {
 468         BUG_ON(!xattr);
 469
 470         if (xattr->should_free_name)
 471                 kfree((void *)xattr->name);
 472         if (xattr->should_free_val)
 473                 kfree((void *)xattr->val);
 474
 475         kfree(xattr);
 476 }
 477
 478 static int __remove_xattr(struct ceph_inode_info *ci,
 479                           struct ceph_inode_xattr *xattr)
 480 {
 481         if (!xattr)
 482                 return -ENODATA;
 483
 484         rb_erase(&xattr->node, &ci->i_xattrs.index);
 485
 486         if (xattr->should_free_name)
 487                 kfree((void *)xattr->name);
 488         if (xattr->should_free_val)
 489                 kfree((void *)xattr->val);
 490
 491         ci->i_xattrs.names_size -= xattr->name_len;
 492         ci->i_xattrs.vals_size -= xattr->val_len;
 493         ci->i_xattrs.count--;
 494         kfree(xattr);
 495
 496         return 0;
 497 }
 498
 499 static int __remove_xattr_by_name(struct ceph_inode_info *ci,
 500                            const char *name)
 501 {
 502         struct rb_node **p;
 503         struct ceph_inode_xattr *xattr;
 504         int err;
 505
 506         p = &ci->i_xattrs.index.rb_node;
 507         xattr = __get_xattr(ci, name);
 508         err = __remove_xattr(ci, xattr);
 509         return err;
 510 }
 511
 512 static char *__copy_xattr_names(struct ceph_inode_info *ci,
 513                                 char *dest)
 514 {
 515         struct rb_node *p;
 516         struct ceph_inode_xattr *xattr = NULL;
 517
 518         p = rb_first(&ci->i_xattrs.index);
 519         dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 520
 521         while (p) {
 522                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 523                 memcpy(dest, xattr->name, xattr->name_len);
 524                 dest[xattr->name_len] = '\0';
 525
 526                 dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 527                      xattr->name_len, ci->i_xattrs.names_size);
 528
 529                 dest += xattr->name_len + 1;
 530                 p = rb_next(p);
 531         }
 532
 533         return dest;
 534 }
 535
 536 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 537 {
 538         struct rb_node *p, *tmp;
 539         struct ceph_inode_xattr *xattr = NULL;
 540
 541         p = rb_first(&ci->i_xattrs.index);
 542
 543         dout("__ceph_destroy_xattrs p=%p\n", p);
 544
 545         while (p) {
 546                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 547                 tmp = p;
 548                 p = rb_next(tmp);
 549                 dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 550                      xattr->name_len, xattr->name);
 551                 rb_erase(tmp, &ci->i_xattrs.index);
 552
 553                 __free_xattr(xattr);
 554         }
 555
 556         ci->i_xattrs.names_size = 0;
 557         ci->i_xattrs.vals_size = 0;
 558         ci->i_xattrs.index_version = 0;
 559         ci->i_xattrs.count = 0;
 560         ci->i_xattrs.index = RB_ROOT;
 561 }
 562
 563 static int __build_xattrs(struct inode *inode)
 564         __releases(ci->i_ceph_lock)
 565         __acquires(ci->i_ceph_lock)
 566 {
 567         u32 namelen;
 568         u32 numattr = 0;
 569         void *p, *end;
 570         u32 len;
 571         const char *name, *val;
 572         struct ceph_inode_info *ci = ceph_inode(inode);
 573         int xattr_version;
 574         struct ceph_inode_xattr **xattrs = NULL;
 575         int err = 0;
 576         int i;
 577
 578         dout("__build_xattrs() len=%d\n",
 579              ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 580
 581         if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 582                 return 0; /* already built */
 583
 584         __ceph_destroy_xattrs(ci);
 585
 586 start:
 587         /* updated internal xattr rb tree */
 588         if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 589                 p = ci->i_xattrs.blob->vec.iov_base;
 590                 end = p + ci->i_xattrs.blob->vec.iov_len;
 591                 ceph_decode_32_safe(&p, end, numattr, bad);
 592                 xattr_version = ci->i_xattrs.version;
 593                 spin_unlock(&ci->i_ceph_lock);
 594
 595                 xattrs = kcalloc(numattr, sizeof(struct ceph_inode_xattr *),
 596                                  GFP_NOFS);
 597                 err = -ENOMEM;
 598                 if (!xattrs)
 599                         goto bad_lock;
 600
 601                 for (i = 0; i < numattr; i++) {
 602                         xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 603                                             GFP_NOFS);
 604                         if (!xattrs[i])
 605                                 goto bad_lock;
 606                 }
 607
 608                 spin_lock(&ci->i_ceph_lock);
 609                 if (ci->i_xattrs.version != xattr_version) {
 610                         /* lost a race, retry */
 611                         for (i = 0; i < numattr; i++)
 612                                 kfree(xattrs[i]);
 613                         kfree(xattrs);
 614                         xattrs = NULL;
 615                         goto start;
 616                 }
 617                 err = -EIO;
 618                 while (numattr--) {
 619                         ceph_decode_32_safe(&p, end, len, bad);
 620                         namelen = len;
 621                         name = p;
 622                         p += len;
 623                         ceph_decode_32_safe(&p, end, len, bad);
 624                         val = p;
 625                         p += len;
 626
 627                         err = __set_xattr(ci, name, namelen, val, len,
 628                                           0, 0, &xattrs[numattr]);
 629
 630                         if (err < 0)
 631                                 goto bad;
 632                 }
 633                 kfree(xattrs);
 634         }
 635         ci->i_xattrs.index_version = ci->i_xattrs.version;
 636         ci->i_xattrs.dirty = false;
 637
 638         return err;
 639 bad_lock:
 640         spin_lock(&ci->i_ceph_lock);
 641 bad:
 642         if (xattrs) {
 643                 for (i = 0; i < numattr; i++)
 644                         kfree(xattrs[i]);
 645                 kfree(xattrs);
 646         }
 647         ci->i_xattrs.names_size = 0;
 648         return err;
 649 }
 650
 651 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 652                                     int val_size)
 653 {
 654         /*
 655          * 4 bytes for the length, and additional 4 bytes per each xattr name,
 656          * 4 bytes per each value
 657          */
 658         int size = 4 + ci->i_xattrs.count*(4 + 4) +
 659                              ci->i_xattrs.names_size +
 660                              ci->i_xattrs.vals_size;
 661         dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 662              ci->i_xattrs.count, ci->i_xattrs.names_size,
 663              ci->i_xattrs.vals_size);
 664
 665         if (name_size)
 666                 size += 4 + 4 + name_size + val_size;
 667
 668         return size;
 669 }
 670
 671 /*
 672  * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 673  * and swap into place.
 674  */
 675 void __ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 676 {
 677         struct rb_node *p;
 678         struct ceph_inode_xattr *xattr = NULL;
 679         void *dest;
 680
 681         dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 682         if (ci->i_xattrs.dirty) {
 683                 int need = __get_required_blob_size(ci, 0, 0);
 684
 685                 BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 686
 687                 p = rb_first(&ci->i_xattrs.index);
 688                 dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 689
 690                 ceph_encode_32(&dest, ci->i_xattrs.count);
 691                 while (p) {
 692                         xattr = rb_entry(p, struct ceph_inode_xattr, node);
 693
 694                         ceph_encode_32(&dest, xattr->name_len);
 695                         memcpy(dest, xattr->name, xattr->name_len);
 696                         dest += xattr->name_len;
 697                         ceph_encode_32(&dest, xattr->val_len);
 698                         memcpy(dest, xattr->val, xattr->val_len);
 699                         dest += xattr->val_len;
 700
 701                         p = rb_next(p);
 702                 }
 703
 704                 /* adjust buffer len; it may be larger than we need */
 705                 ci->i_xattrs.prealloc_blob->vec.iov_len =
 706                         dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 707
 708                 if (ci->i_xattrs.blob)
 709                         ceph_buffer_put(ci->i_xattrs.blob);
 710                 ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 711                 ci->i_xattrs.prealloc_blob = NULL;
 712                 ci->i_xattrs.dirty = false;
 713                 ci->i_xattrs.version++;
 714         }
 715 }
 716
 717 ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 718                       size_t size)
 719 {
 720         struct ceph_inode_info *ci = ceph_inode(inode);
 721         int err;
 722         struct ceph_inode_xattr *xattr;
 723         struct ceph_vxattr *vxattr = NULL;
 724
 725         if (!ceph_is_valid_xattr(name))
 726                 return -ENODATA;
 727
 728         /* let's see if a virtual xattr was requested */
 729         vxattr = ceph_match_vxattr(inode, name);
 730         if (vxattr && !(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
 731                 err = vxattr->getxattr_cb(ci, value, size);
 732                 return err;
 733         }
 734
 735         spin_lock(&ci->i_ceph_lock);
 736         dout("getxattr %p ver=%lld index_ver=%lld\n", inode,
 737              ci->i_xattrs.version, ci->i_xattrs.index_version);
 738
 739         if (ci->i_xattrs.version == 0 ||
 740             !__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
 741                 spin_unlock(&ci->i_ceph_lock);
 742                 /* get xattrs from mds (if we don't already have them) */
 743                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 744                 if (err)
 745                         return err;
 746                 spin_lock(&ci->i_ceph_lock);
 747         }
 748
 749         err = __build_xattrs(inode);
 750         if (err < 0)
 751                 goto out;
 752
 753         err = -ENODATA;  /* == ENOATTR */
 754         xattr = __get_xattr(ci, name);
 755         if (!xattr)
 756                 goto out;
 757
 758         err = -ERANGE;
 759         if (size && size < xattr->val_len)
 760                 goto out;
 761
 762         err = xattr->val_len;
 763         if (size == 0)
 764                 goto out;
 765
 766         memcpy(value, xattr->val, xattr->val_len);
 767
 768 out:
 769         spin_unlock(&ci->i_ceph_lock);
 770         return err;
 771 }
 772
 773 ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
 774                       size_t size)
 775 {
 776         if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
 777                 return generic_getxattr(dentry, name, value, size);
 778
 779         return __ceph_getxattr(d_inode(dentry), name, value, size);
 780 }
 781
 782 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 783 {
 784         struct inode *inode = d_inode(dentry);
 785         struct ceph_inode_info *ci = ceph_inode(inode);
 786         struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
 787         u32 vir_namelen = 0;
 788         u32 namelen;
 789         int err;
 790         u32 len;
 791         int i;
 792
 793         spin_lock(&ci->i_ceph_lock);
 794         dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
 795              ci->i_xattrs.version, ci->i_xattrs.index_version);
 796
 797         if (ci->i_xattrs.version == 0 ||
 798             !__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
 799                 spin_unlock(&ci->i_ceph_lock);
 800                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 801                 if (err)
 802                         return err;
 803                 spin_lock(&ci->i_ceph_lock);
 804         }
 805
 806         err = __build_xattrs(inode);
 807         if (err < 0)
 808                 goto out;
 809         /*
 810          * Start with virtual dir xattr names (if any) (including
 811          * terminating '\0' characters for each).
 812          */
 813         vir_namelen = ceph_vxattrs_name_size(vxattrs);
 814
 815         /* adding 1 byte per each variable due to the null termination */
 816         namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
 817         err = -ERANGE;
 818         if (size && vir_namelen + namelen > size)
 819                 goto out;
 820
 821         err = namelen + vir_namelen;
 822         if (size == 0)
 823                 goto out;
 824
 825         names = __copy_xattr_names(ci, names);
 826
 827         /* virtual xattr names, too */
 828         err = namelen;
 829         if (vxattrs) {
 830                 for (i = 0; vxattrs[i].name; i++) {
 831                         if (!vxattrs[i].hidden &&
 832                             !(vxattrs[i].exists_cb &&
 833                               !vxattrs[i].exists_cb(ci))) {
 834                                 len = sprintf(names, "%s", vxattrs[i].name);
 835                                 names += len + 1;
 836                                 err += len + 1;
 837                         }
 838                 }
 839         }
 840
 841 out:
 842         spin_unlock(&ci->i_ceph_lock);
 843         return err;
 844 }
 845
 846 static int ceph_sync_setxattr(struct dentry *dentry, const char *name,
 847                               const char *value, size_t size, int flags)
 848 {
 849         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 850         struct inode *inode = d_inode(dentry);
 851         struct ceph_inode_info *ci = ceph_inode(inode);
 852         struct ceph_mds_request *req;
 853         struct ceph_mds_client *mdsc = fsc->mdsc;
 854         struct ceph_pagelist *pagelist = NULL;
 855         int err;
 856
 857         if (size > 0) {
 858                 /* copy value into pagelist */
 859                 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
 860                 if (!pagelist)
 861                         return -ENOMEM;
 862
 863                 ceph_pagelist_init(pagelist);
 864                 err = ceph_pagelist_append(pagelist, value, size);
 865                 if (err)
 866                         goto out;
 867         } else if (!value) {
 868                 flags |= CEPH_XATTR_REMOVE;
 869         }
 870
 871         dout("setxattr value=%.*s\n", (int)size, value);
 872
 873         /* do request */
 874         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
 875                                        USE_AUTH_MDS);
 876         if (IS_ERR(req)) {
 877                 err = PTR_ERR(req);
 878                 goto out;
 879         }
 880
 881         req->r_args.setxattr.flags = cpu_to_le32(flags);
 882         req->r_path2 = kstrdup(name, GFP_NOFS);
 883         if (!req->r_path2) {
 884                 ceph_mdsc_put_request(req);
 885                 err = -ENOMEM;
 886                 goto out;
 887         }
 888
 889         req->r_pagelist = pagelist;
 890         pagelist = NULL;
 891
 892         req->r_inode = inode;
 893         ihold(inode);
 894         req->r_num_caps = 1;
 895         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
 896
 897         dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
 898         err = ceph_mdsc_do_request(mdsc, NULL, req);
 899         ceph_mdsc_put_request(req);
 900         dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
 901
 902 out:
 903         if (pagelist)
 904                 ceph_pagelist_release(pagelist);
 905         return err;
 906 }
 907
 908 int __ceph_setxattr(struct dentry *dentry, const char *name,
 909                         const void *value, size_t size, int flags)
 910 {
 911         struct inode *inode = d_inode(dentry);
 912         struct ceph_vxattr *vxattr;
 913         struct ceph_inode_info *ci = ceph_inode(inode);
 914         struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
 915         struct ceph_cap_flush *prealloc_cf = NULL;
 916         int issued;
 917         int err;
 918         int dirty = 0;
 919         int name_len = strlen(name);
 920         int val_len = size;
 921         char *newname = NULL;
 922         char *newval = NULL;
 923         struct ceph_inode_xattr *xattr = NULL;
 924         int required_blob_size;
 925         bool lock_snap_rwsem = false;
 926
 927         if (!ceph_is_valid_xattr(name))
 928                 return -EOPNOTSUPP;
 929
 930         vxattr = ceph_match_vxattr(inode, name);
 931         if (vxattr && vxattr->readonly)
 932                 return -EOPNOTSUPP;
 933
 934         /* pass any unhandled ceph.* xattrs through to the MDS */
 935         if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
 936                 goto do_sync_unlocked;
 937
 938         /* preallocate memory for xattr name, value, index node */
 939         err = -ENOMEM;
 940         newname = kmemdup(name, name_len + 1, GFP_NOFS);
 941         if (!newname)
 942                 goto out;
 943
 944         if (val_len) {
 945                 newval = kmemdup(value, val_len, GFP_NOFS);
 946                 if (!newval)
 947                         goto out;
 948         }
 949
 950         xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
 951         if (!xattr)
 952                 goto out;
 953
 954         prealloc_cf = ceph_alloc_cap_flush();
 955         if (!prealloc_cf)
 956                 goto out;
 957
 958         spin_lock(&ci->i_ceph_lock);
 959 retry:
 960         issued = __ceph_caps_issued(ci, NULL);
 961         if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
 962                 goto do_sync;
 963
 964         if (!lock_snap_rwsem && !ci->i_head_snapc) {
 965                 lock_snap_rwsem = true;
 966                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
 967                         spin_unlock(&ci->i_ceph_lock);
 968                         down_read(&mdsc->snap_rwsem);
 969                         spin_lock(&ci->i_ceph_lock);
 970                         goto retry;
 971                 }
 972         }
 973
 974         dout("setxattr %p issued %s\n", inode, ceph_cap_string(issued));
 975         __build_xattrs(inode);
 976
 977         required_blob_size = __get_required_blob_size(ci, name_len, val_len);
 978
 979         if (!ci->i_xattrs.prealloc_blob ||
 980             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
 981                 struct ceph_buffer *blob;
 982
 983                 spin_unlock(&ci->i_ceph_lock);
 984                 dout(" preaallocating new blob size=%d\n", required_blob_size);
 985                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
 986                 if (!blob)
 987                         goto do_sync_unlocked;
 988                 spin_lock(&ci->i_ceph_lock);
 989                 if (ci->i_xattrs.prealloc_blob)
 990                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 991                 ci->i_xattrs.prealloc_blob = blob;
 992                 goto retry;
 993         }
 994
 995         err = __set_xattr(ci, newname, name_len, newval, val_len,
 996                           flags, value ? 1 : -1, &xattr);
 997
 998         if (!err) {
 999                 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1000                                                &prealloc_cf);
1001                 ci->i_xattrs.dirty = true;
1002                 inode->i_ctime = CURRENT_TIME;
1003         }
1004
1005         spin_unlock(&ci->i_ceph_lock);
1006         if (lock_snap_rwsem)
1007                 up_read(&mdsc->snap_rwsem);
1008         if (dirty)
1009                 __mark_inode_dirty(inode, dirty);
1010         ceph_free_cap_flush(prealloc_cf);
1011         return err;
1012
1013 do_sync:
1014         spin_unlock(&ci->i_ceph_lock);
1015 do_sync_unlocked:
1016         if (lock_snap_rwsem)
1017                 up_read(&mdsc->snap_rwsem);
1018         err = ceph_sync_setxattr(dentry, name, value, size, flags);
1019 out:
1020         ceph_free_cap_flush(prealloc_cf);
1021         kfree(newname);
1022         kfree(newval);
1023         kfree(xattr);
1024         return err;
1025 }
1026
1027 int ceph_setxattr(struct dentry *dentry, const char *name,
1028                   const void *value, size_t size, int flags)
1029 {
1030         if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
1031                 return -EROFS;
1032
1033         if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
1034                 return generic_setxattr(dentry, name, value, size, flags);
1035
1036         if (size == 0)
1037                 value = "";  /* empty EA, do not remove */
1038
1039         return __ceph_setxattr(dentry, name, value, size, flags);
1040 }
1041
1042 static int ceph_send_removexattr(struct dentry *dentry, const char *name)
1043 {
1044         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
1045         struct ceph_mds_client *mdsc = fsc->mdsc;
1046         struct inode *inode = d_inode(dentry);
1047         struct ceph_mds_request *req;
1048         int err;
1049
1050         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RMXATTR,
1051                                        USE_AUTH_MDS);
1052         if (IS_ERR(req))
1053                 return PTR_ERR(req);
1054         req->r_path2 = kstrdup(name, GFP_NOFS);
1055         if (!req->r_path2)
1056                 return -ENOMEM;
1057
1058         req->r_inode = inode;
1059         ihold(inode);
1060         req->r_num_caps = 1;
1061         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
1062         err = ceph_mdsc_do_request(mdsc, NULL, req);
1063         ceph_mdsc_put_request(req);
1064         return err;
1065 }
1066
1067 int __ceph_removexattr(struct dentry *dentry, const char *name)
1068 {
1069         struct inode *inode = d_inode(dentry);
1070         struct ceph_vxattr *vxattr;
1071         struct ceph_inode_info *ci = ceph_inode(inode);
1072         struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
1073         struct ceph_cap_flush *prealloc_cf = NULL;
1074         int issued;
1075         int err;
1076         int required_blob_size;
1077         int dirty;
1078         bool lock_snap_rwsem = false;
1079
1080         if (!ceph_is_valid_xattr(name))
1081                 return -EOPNOTSUPP;
1082
1083         vxattr = ceph_match_vxattr(inode, name);
1084         if (vxattr && vxattr->readonly)
1085                 return -EOPNOTSUPP;
1086
1087         /* pass any unhandled ceph.* xattrs through to the MDS */
1088         if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
1089                 goto do_sync_unlocked;
1090
1091         prealloc_cf = ceph_alloc_cap_flush();
1092         if (!prealloc_cf)
1093                 return -ENOMEM;
1094
1095         err = -ENOMEM;
1096         spin_lock(&ci->i_ceph_lock);
1097 retry:
1098         issued = __ceph_caps_issued(ci, NULL);
1099         if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
1100                 goto do_sync;
1101
1102         if (!lock_snap_rwsem && !ci->i_head_snapc) {
1103                 lock_snap_rwsem = true;
1104                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
1105                         spin_unlock(&ci->i_ceph_lock);
1106                         down_read(&mdsc->snap_rwsem);
1107                         spin_lock(&ci->i_ceph_lock);
1108                         goto retry;
1109                 }
1110         }
1111
1112         dout("removexattr %p issued %s\n", inode, ceph_cap_string(issued));
1113
1114         __build_xattrs(inode);
1115
1116         required_blob_size = __get_required_blob_size(ci, 0, 0);
1117
1118         if (!ci->i_xattrs.prealloc_blob ||
1119             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
1120                 struct ceph_buffer *blob;
1121
1122                 spin_unlock(&ci->i_ceph_lock);
1123                 dout(" preaallocating new blob size=%d\n", required_blob_size);
1124                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
1125                 if (!blob)
1126                         goto do_sync_unlocked;
1127                 spin_lock(&ci->i_ceph_lock);
1128                 if (ci->i_xattrs.prealloc_blob)
1129                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
1130                 ci->i_xattrs.prealloc_blob = blob;
1131                 goto retry;
1132         }
1133
1134         err = __remove_xattr_by_name(ceph_inode(inode), name);
1135
1136         dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1137                                        &prealloc_cf);
1138         ci->i_xattrs.dirty = true;
1139         inode->i_ctime = CURRENT_TIME;
1140         spin_unlock(&ci->i_ceph_lock);
1141         if (lock_snap_rwsem)
1142                 up_read(&mdsc->snap_rwsem);
1143         if (dirty)
1144                 __mark_inode_dirty(inode, dirty);
1145         ceph_free_cap_flush(prealloc_cf);
1146         return err;
1147 do_sync:
1148         spin_unlock(&ci->i_ceph_lock);
1149 do_sync_unlocked:
1150         if (lock_snap_rwsem)
1151                 up_read(&mdsc->snap_rwsem);
1152         ceph_free_cap_flush(prealloc_cf);
1153         err = ceph_send_removexattr(dentry, name);
1154         return err;
1155 }
1156
1157 int ceph_removexattr(struct dentry *dentry, const char *name)
1158 {
1159         if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
1160                 return -EROFS;
1161
1162         if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
1163                 return generic_removexattr(dentry, name);
1164
1165         return __ceph_removexattr(dentry, name);
1166 }