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
 373                 if (xattr && (flags & XATTR_CREATE))
 374                         err = -EEXIST;
 375                 else if (!xattr && (flags & XATTR_REPLACE))
 376                         err = -ENODATA;
 377                 if (err) {
 378                         kfree(name);
 379                         kfree(val);
 380                         kfree(*newxattr);
 381                         return err;
 382                 }
 383                 if (update_xattr < 0) {
 384                         if (xattr)
 385                                 __remove_xattr(ci, xattr);
 386                         kfree(name);
 387                         kfree(*newxattr);
 388                         return 0;
 389                 }
 390         }
 391
 392         if (!xattr) {
 393                 new = 1;
 394                 xattr = *newxattr;
 395                 xattr->name = name;
 396                 xattr->name_len = name_len;
 397                 xattr->should_free_name = update_xattr;
 398
 399                 ci->i_xattrs.count++;
 400                 dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 401         } else {
 402                 kfree(*newxattr);
 403                 *newxattr = NULL;
 404                 if (xattr->should_free_val)
 405                         kfree((void *)xattr->val);
 406
 407                 if (update_xattr) {
 408                         kfree((void *)name);
 409                         name = xattr->name;
 410                 }
 411                 ci->i_xattrs.names_size -= xattr->name_len;
 412                 ci->i_xattrs.vals_size -= xattr->val_len;
 413         }
 414         ci->i_xattrs.names_size += name_len;
 415         ci->i_xattrs.vals_size += val_len;
 416         if (val)
 417                 xattr->val = val;
 418         else
 419                 xattr->val = "";
 420
 421         xattr->val_len = val_len;
 422         xattr->dirty = update_xattr;
 423         xattr->should_free_val = (val && update_xattr);
 424
 425         if (new) {
 426                 rb_link_node(&xattr->node, parent, p);
 427                 rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 428                 dout("__set_xattr_val p=%p\n", p);
 429         }
 430
 431         dout("__set_xattr_val added %llx.%llx xattr %p %s=%.*s\n",
 432              ceph_vinop(&ci->vfs_inode), xattr, name, val_len, val);
 433
 434         return 0;
 435 }
 436
 437 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 438                            const char *name)
 439 {
 440         struct rb_node **p;
 441         struct rb_node *parent = NULL;
 442         struct ceph_inode_xattr *xattr = NULL;
 443         int name_len = strlen(name);
 444         int c;
 445
 446         p = &ci->i_xattrs.index.rb_node;
 447         while (*p) {
 448                 parent = *p;
 449                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 450                 c = strncmp(name, xattr->name, xattr->name_len);
 451                 if (c == 0 && name_len > xattr->name_len)
 452                         c = 1;
 453                 if (c < 0)
 454                         p = &(*p)->rb_left;
 455                 else if (c > 0)
 456                         p = &(*p)->rb_right;
 457                 else {
 458                         dout("__get_xattr %s: found %.*s\n", name,
 459                              xattr->val_len, xattr->val);
 460                         return xattr;
 461                 }
 462         }
 463
 464         dout("__get_xattr %s: not found\n", name);
 465
 466         return NULL;
 467 }
 468
 469 static void __free_xattr(struct ceph_inode_xattr *xattr)
 470 {
 471         BUG_ON(!xattr);
 472
 473         if (xattr->should_free_name)
 474                 kfree((void *)xattr->name);
 475         if (xattr->should_free_val)
 476                 kfree((void *)xattr->val);
 477
 478         kfree(xattr);
 479 }
 480
 481 static int __remove_xattr(struct ceph_inode_info *ci,
 482                           struct ceph_inode_xattr *xattr)
 483 {
 484         if (!xattr)
 485                 return -ENODATA;
 486
 487         rb_erase(&xattr->node, &ci->i_xattrs.index);
 488
 489         if (xattr->should_free_name)
 490                 kfree((void *)xattr->name);
 491         if (xattr->should_free_val)
 492                 kfree((void *)xattr->val);
 493
 494         ci->i_xattrs.names_size -= xattr->name_len;
 495         ci->i_xattrs.vals_size -= xattr->val_len;
 496         ci->i_xattrs.count--;
 497         kfree(xattr);
 498
 499         return 0;
 500 }
 501
 502 static int __remove_xattr_by_name(struct ceph_inode_info *ci,
 503                            const char *name)
 504 {
 505         struct rb_node **p;
 506         struct ceph_inode_xattr *xattr;
 507         int err;
 508
 509         p = &ci->i_xattrs.index.rb_node;
 510         xattr = __get_xattr(ci, name);
 511         err = __remove_xattr(ci, xattr);
 512         return err;
 513 }
 514
 515 static char *__copy_xattr_names(struct ceph_inode_info *ci,
 516                                 char *dest)
 517 {
 518         struct rb_node *p;
 519         struct ceph_inode_xattr *xattr = NULL;
 520
 521         p = rb_first(&ci->i_xattrs.index);
 522         dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 523
 524         while (p) {
 525                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 526                 memcpy(dest, xattr->name, xattr->name_len);
 527                 dest[xattr->name_len] = '\0';
 528
 529                 dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 530                      xattr->name_len, ci->i_xattrs.names_size);
 531
 532                 dest += xattr->name_len + 1;
 533                 p = rb_next(p);
 534         }
 535
 536         return dest;
 537 }
 538
 539 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 540 {
 541         struct rb_node *p, *tmp;
 542         struct ceph_inode_xattr *xattr = NULL;
 543
 544         p = rb_first(&ci->i_xattrs.index);
 545
 546         dout("__ceph_destroy_xattrs p=%p\n", p);
 547
 548         while (p) {
 549                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 550                 tmp = p;
 551                 p = rb_next(tmp);
 552                 dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 553                      xattr->name_len, xattr->name);
 554                 rb_erase(tmp, &ci->i_xattrs.index);
 555
 556                 __free_xattr(xattr);
 557         }
 558
 559         ci->i_xattrs.names_size = 0;
 560         ci->i_xattrs.vals_size = 0;
 561         ci->i_xattrs.index_version = 0;
 562         ci->i_xattrs.count = 0;
 563         ci->i_xattrs.index = RB_ROOT;
 564 }
 565
 566 static int __build_xattrs(struct inode *inode)
 567         __releases(ci->i_ceph_lock)
 568         __acquires(ci->i_ceph_lock)
 569 {
 570         u32 namelen;
 571         u32 numattr = 0;
 572         void *p, *end;
 573         u32 len;
 574         const char *name, *val;
 575         struct ceph_inode_info *ci = ceph_inode(inode);
 576         int xattr_version;
 577         struct ceph_inode_xattr **xattrs = NULL;
 578         int err = 0;
 579         int i;
 580
 581         dout("__build_xattrs() len=%d\n",
 582              ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 583
 584         if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 585                 return 0; /* already built */
 586
 587         __ceph_destroy_xattrs(ci);
 588
 589 start:
 590         /* updated internal xattr rb tree */
 591         if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 592                 p = ci->i_xattrs.blob->vec.iov_base;
 593                 end = p + ci->i_xattrs.blob->vec.iov_len;
 594                 ceph_decode_32_safe(&p, end, numattr, bad);
 595                 xattr_version = ci->i_xattrs.version;
 596                 spin_unlock(&ci->i_ceph_lock);
 597
 598                 xattrs = kcalloc(numattr, sizeof(struct ceph_inode_xattr *),
 599                                  GFP_NOFS);
 600                 err = -ENOMEM;
 601                 if (!xattrs)
 602                         goto bad_lock;
 603
 604                 for (i = 0; i < numattr; i++) {
 605                         xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 606                                             GFP_NOFS);
 607                         if (!xattrs[i])
 608                                 goto bad_lock;
 609                 }
 610
 611                 spin_lock(&ci->i_ceph_lock);
 612                 if (ci->i_xattrs.version != xattr_version) {
 613                         /* lost a race, retry */
 614                         for (i = 0; i < numattr; i++)
 615                                 kfree(xattrs[i]);
 616                         kfree(xattrs);
 617                         xattrs = NULL;
 618                         goto start;
 619                 }
 620                 err = -EIO;
 621                 while (numattr--) {
 622                         ceph_decode_32_safe(&p, end, len, bad);
 623                         namelen = len;
 624                         name = p;
 625                         p += len;
 626                         ceph_decode_32_safe(&p, end, len, bad);
 627                         val = p;
 628                         p += len;
 629
 630                         err = __set_xattr(ci, name, namelen, val, len,
 631                                           0, 0, &xattrs[numattr]);
 632
 633                         if (err < 0)
 634                                 goto bad;
 635                 }
 636                 kfree(xattrs);
 637         }
 638         ci->i_xattrs.index_version = ci->i_xattrs.version;
 639         ci->i_xattrs.dirty = false;
 640
 641         return err;
 642 bad_lock:
 643         spin_lock(&ci->i_ceph_lock);
 644 bad:
 645         if (xattrs) {
 646                 for (i = 0; i < numattr; i++)
 647                         kfree(xattrs[i]);
 648                 kfree(xattrs);
 649         }
 650         ci->i_xattrs.names_size = 0;
 651         return err;
 652 }
 653
 654 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 655                                     int val_size)
 656 {
 657         /*
 658          * 4 bytes for the length, and additional 4 bytes per each xattr name,
 659          * 4 bytes per each value
 660          */
 661         int size = 4 + ci->i_xattrs.count*(4 + 4) +
 662                              ci->i_xattrs.names_size +
 663                              ci->i_xattrs.vals_size;
 664         dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 665              ci->i_xattrs.count, ci->i_xattrs.names_size,
 666              ci->i_xattrs.vals_size);
 667
 668         if (name_size)
 669                 size += 4 + 4 + name_size + val_size;
 670
 671         return size;
 672 }
 673
 674 /*
 675  * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 676  * and swap into place.
 677  */
 678 void __ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 679 {
 680         struct rb_node *p;
 681         struct ceph_inode_xattr *xattr = NULL;
 682         void *dest;
 683
 684         dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 685         if (ci->i_xattrs.dirty) {
 686                 int need = __get_required_blob_size(ci, 0, 0);
 687
 688                 BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 689
 690                 p = rb_first(&ci->i_xattrs.index);
 691                 dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 692
 693                 ceph_encode_32(&dest, ci->i_xattrs.count);
 694                 while (p) {
 695                         xattr = rb_entry(p, struct ceph_inode_xattr, node);
 696
 697                         ceph_encode_32(&dest, xattr->name_len);
 698                         memcpy(dest, xattr->name, xattr->name_len);
 699                         dest += xattr->name_len;
 700                         ceph_encode_32(&dest, xattr->val_len);
 701                         memcpy(dest, xattr->val, xattr->val_len);
 702                         dest += xattr->val_len;
 703
 704                         p = rb_next(p);
 705                 }
 706
 707                 /* adjust buffer len; it may be larger than we need */
 708                 ci->i_xattrs.prealloc_blob->vec.iov_len =
 709                         dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 710
 711                 if (ci->i_xattrs.blob)
 712                         ceph_buffer_put(ci->i_xattrs.blob);
 713                 ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 714                 ci->i_xattrs.prealloc_blob = NULL;
 715                 ci->i_xattrs.dirty = false;
 716                 ci->i_xattrs.version++;
 717         }
 718 }
 719
 720 ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 721                       size_t size)
 722 {
 723         struct ceph_inode_info *ci = ceph_inode(inode);
 724         int err;
 725         struct ceph_inode_xattr *xattr;
 726         struct ceph_vxattr *vxattr = NULL;
 727
 728         if (!ceph_is_valid_xattr(name))
 729                 return -ENODATA;
 730
 731         /* let's see if a virtual xattr was requested */
 732         vxattr = ceph_match_vxattr(inode, name);
 733         if (vxattr && !(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
 734                 err = vxattr->getxattr_cb(ci, value, size);
 735                 return err;
 736         }
 737
 738         spin_lock(&ci->i_ceph_lock);
 739         dout("getxattr %p ver=%lld index_ver=%lld\n", inode,
 740              ci->i_xattrs.version, ci->i_xattrs.index_version);
 741
 742         if (ci->i_xattrs.version == 0 ||
 743             !__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
 744                 spin_unlock(&ci->i_ceph_lock);
 745                 /* get xattrs from mds (if we don't already have them) */
 746                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 747                 if (err)
 748                         return err;
 749                 spin_lock(&ci->i_ceph_lock);
 750         }
 751
 752         err = __build_xattrs(inode);
 753         if (err < 0)
 754                 goto out;
 755
 756         err = -ENODATA;  /* == ENOATTR */
 757         xattr = __get_xattr(ci, name);
 758         if (!xattr)
 759                 goto out;
 760
 761         err = -ERANGE;
 762         if (size && size < xattr->val_len)
 763                 goto out;
 764
 765         err = xattr->val_len;
 766         if (size == 0)
 767                 goto out;
 768
 769         memcpy(value, xattr->val, xattr->val_len);
 770
 771 out:
 772         spin_unlock(&ci->i_ceph_lock);
 773         return err;
 774 }
 775
 776 ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
 777                       size_t size)
 778 {
 779         if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
 780                 return generic_getxattr(dentry, name, value, size);
 781
 782         return __ceph_getxattr(d_inode(dentry), name, value, size);
 783 }
 784
 785 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 786 {
 787         struct inode *inode = d_inode(dentry);
 788         struct ceph_inode_info *ci = ceph_inode(inode);
 789         struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
 790         u32 vir_namelen = 0;
 791         u32 namelen;
 792         int err;
 793         u32 len;
 794         int i;
 795
 796         spin_lock(&ci->i_ceph_lock);
 797         dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
 798              ci->i_xattrs.version, ci->i_xattrs.index_version);
 799
 800         if (ci->i_xattrs.version == 0 ||
 801             !__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
 802                 spin_unlock(&ci->i_ceph_lock);
 803                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 804                 if (err)
 805                         return err;
 806                 spin_lock(&ci->i_ceph_lock);
 807         }
 808
 809         err = __build_xattrs(inode);
 810         if (err < 0)
 811                 goto out;
 812         /*
 813          * Start with virtual dir xattr names (if any) (including
 814          * terminating '\0' characters for each).
 815          */
 816         vir_namelen = ceph_vxattrs_name_size(vxattrs);
 817
 818         /* adding 1 byte per each variable due to the null termination */
 819         namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
 820         err = -ERANGE;
 821         if (size && vir_namelen + namelen > size)
 822                 goto out;
 823
 824         err = namelen + vir_namelen;
 825         if (size == 0)
 826                 goto out;
 827
 828         names = __copy_xattr_names(ci, names);
 829
 830         /* virtual xattr names, too */
 831         err = namelen;
 832         if (vxattrs) {
 833                 for (i = 0; vxattrs[i].name; i++) {
 834                         if (!vxattrs[i].hidden &&
 835                             !(vxattrs[i].exists_cb &&
 836                               !vxattrs[i].exists_cb(ci))) {
 837                                 len = sprintf(names, "%s", vxattrs[i].name);
 838                                 names += len + 1;
 839                                 err += len + 1;
 840                         }
 841                 }
 842         }
 843
 844 out:
 845         spin_unlock(&ci->i_ceph_lock);
 846         return err;
 847 }
 848
 849 static int ceph_sync_setxattr(struct dentry *dentry, const char *name,
 850                               const char *value, size_t size, int flags)
 851 {
 852         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 853         struct inode *inode = d_inode(dentry);
 854         struct ceph_inode_info *ci = ceph_inode(inode);
 855         struct ceph_mds_request *req;
 856         struct ceph_mds_client *mdsc = fsc->mdsc;
 857         struct ceph_pagelist *pagelist = NULL;
 858         int err;
 859
 860         if (size > 0) {
 861                 /* copy value into pagelist */
 862                 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
 863                 if (!pagelist)
 864                         return -ENOMEM;
 865
 866                 ceph_pagelist_init(pagelist);
 867                 err = ceph_pagelist_append(pagelist, value, size);
 868                 if (err)
 869                         goto out;
 870         } else if (!value) {
 871                 flags |= CEPH_XATTR_REMOVE;
 872         }
 873
 874         dout("setxattr value=%.*s\n", (int)size, value);
 875
 876         /* do request */
 877         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
 878                                        USE_AUTH_MDS);
 879         if (IS_ERR(req)) {
 880                 err = PTR_ERR(req);
 881                 goto out;
 882         }
 883
 884         req->r_args.setxattr.flags = cpu_to_le32(flags);
 885         req->r_path2 = kstrdup(name, GFP_NOFS);
 886         if (!req->r_path2) {
 887                 ceph_mdsc_put_request(req);
 888                 err = -ENOMEM;
 889                 goto out;
 890         }
 891
 892         req->r_pagelist = pagelist;
 893         pagelist = NULL;
 894
 895         req->r_inode = inode;
 896         ihold(inode);
 897         req->r_num_caps = 1;
 898         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
 899
 900         dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
 901         err = ceph_mdsc_do_request(mdsc, NULL, req);
 902         ceph_mdsc_put_request(req);
 903         dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
 904
 905 out:
 906         if (pagelist)
 907                 ceph_pagelist_release(pagelist);
 908         return err;
 909 }
 910
 911 int __ceph_setxattr(struct dentry *dentry, const char *name,
 912                         const void *value, size_t size, int flags)
 913 {
 914         struct inode *inode = d_inode(dentry);
 915         struct ceph_vxattr *vxattr;
 916         struct ceph_inode_info *ci = ceph_inode(inode);
 917         struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
 918         struct ceph_cap_flush *prealloc_cf = NULL;
 919         int issued;
 920         int err;
 921         int dirty = 0;
 922         int name_len = strlen(name);
 923         int val_len = size;
 924         char *newname = NULL;
 925         char *newval = NULL;
 926         struct ceph_inode_xattr *xattr = NULL;
 927         int required_blob_size;
 928         bool lock_snap_rwsem = false;
 929
 930         if (!ceph_is_valid_xattr(name))
 931                 return -EOPNOTSUPP;
 932
 933         vxattr = ceph_match_vxattr(inode, name);
 934         if (vxattr && vxattr->readonly)
 935                 return -EOPNOTSUPP;
 936
 937         /* pass any unhandled ceph.* xattrs through to the MDS */
 938         if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
 939                 goto do_sync_unlocked;
 940
 941         /* preallocate memory for xattr name, value, index node */
 942         err = -ENOMEM;
 943         newname = kmemdup(name, name_len + 1, GFP_NOFS);
 944         if (!newname)
 945                 goto out;
 946
 947         if (val_len) {
 948                 newval = kmemdup(value, val_len, GFP_NOFS);
 949                 if (!newval)
 950                         goto out;
 951         }
 952
 953         xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
 954         if (!xattr)
 955                 goto out;
 956
 957         prealloc_cf = ceph_alloc_cap_flush();
 958         if (!prealloc_cf)
 959                 goto out;
 960
 961         spin_lock(&ci->i_ceph_lock);
 962 retry:
 963         issued = __ceph_caps_issued(ci, NULL);
 964         if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
 965                 goto do_sync;
 966
 967         if (!lock_snap_rwsem && !ci->i_head_snapc) {
 968                 lock_snap_rwsem = true;
 969                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
 970                         spin_unlock(&ci->i_ceph_lock);
 971                         down_read(&mdsc->snap_rwsem);
 972                         spin_lock(&ci->i_ceph_lock);
 973                         goto retry;
 974                 }
 975         }
 976
 977         dout("setxattr %p issued %s\n", inode, ceph_cap_string(issued));
 978         __build_xattrs(inode);
 979
 980         required_blob_size = __get_required_blob_size(ci, name_len, val_len);
 981
 982         if (!ci->i_xattrs.prealloc_blob ||
 983             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
 984                 struct ceph_buffer *blob;
 985
 986                 spin_unlock(&ci->i_ceph_lock);
 987                 dout(" preaallocating new blob size=%d\n", required_blob_size);
 988                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
 989                 if (!blob)
 990                         goto do_sync_unlocked;
 991                 spin_lock(&ci->i_ceph_lock);
 992                 if (ci->i_xattrs.prealloc_blob)
 993                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 994                 ci->i_xattrs.prealloc_blob = blob;
 995                 goto retry;
 996         }
 997
 998         err = __set_xattr(ci, newname, name_len, newval, val_len,
 999                           flags, value ? 1 : -1, &xattr);
1000
1001         if (!err) {
1002                 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1003                                                &prealloc_cf);
1004                 ci->i_xattrs.dirty = true;
1005                 inode->i_ctime = CURRENT_TIME;
1006         }
1007
1008         spin_unlock(&ci->i_ceph_lock);
1009         if (lock_snap_rwsem)
1010                 up_read(&mdsc->snap_rwsem);
1011         if (dirty)
1012                 __mark_inode_dirty(inode, dirty);
1013         ceph_free_cap_flush(prealloc_cf);
1014         return err;
1015
1016 do_sync:
1017         spin_unlock(&ci->i_ceph_lock);
1018 do_sync_unlocked:
1019         if (lock_snap_rwsem)
1020                 up_read(&mdsc->snap_rwsem);
1021         err = ceph_sync_setxattr(dentry, name, value, size, flags);
1022 out:
1023         ceph_free_cap_flush(prealloc_cf);
1024         kfree(newname);
1025         kfree(newval);
1026         kfree(xattr);
1027         return err;
1028 }
1029
1030 int ceph_setxattr(struct dentry *dentry, const char *name,
1031                   const void *value, size_t size, int flags)
1032 {
1033         if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
1034                 return -EROFS;
1035
1036         if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
1037                 return generic_setxattr(dentry, name, value, size, flags);
1038
1039         if (size == 0)
1040                 value = "";  /* empty EA, do not remove */
1041
1042         return __ceph_setxattr(dentry, name, value, size, flags);
1043 }
1044
1045 static int ceph_send_removexattr(struct dentry *dentry, const char *name)
1046 {
1047         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
1048         struct ceph_mds_client *mdsc = fsc->mdsc;
1049         struct inode *inode = d_inode(dentry);
1050         struct ceph_mds_request *req;
1051         int err;
1052
1053         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RMXATTR,
1054                                        USE_AUTH_MDS);
1055         if (IS_ERR(req))
1056                 return PTR_ERR(req);
1057         req->r_path2 = kstrdup(name, GFP_NOFS);
1058         if (!req->r_path2)
1059                 return -ENOMEM;
1060
1061         req->r_inode = inode;
1062         ihold(inode);
1063         req->r_num_caps = 1;
1064         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
1065         err = ceph_mdsc_do_request(mdsc, NULL, req);
1066         ceph_mdsc_put_request(req);
1067         return err;
1068 }
1069
1070 int __ceph_removexattr(struct dentry *dentry, const char *name)
1071 {
1072         struct inode *inode = d_inode(dentry);
1073         struct ceph_vxattr *vxattr;
1074         struct ceph_inode_info *ci = ceph_inode(inode);
1075         struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
1076         struct ceph_cap_flush *prealloc_cf = NULL;
1077         int issued;
1078         int err;
1079         int required_blob_size;
1080         int dirty;
1081         bool lock_snap_rwsem = false;
1082
1083         if (!ceph_is_valid_xattr(name))
1084                 return -EOPNOTSUPP;
1085
1086         vxattr = ceph_match_vxattr(inode, name);
1087         if (vxattr && vxattr->readonly)
1088                 return -EOPNOTSUPP;
1089
1090         /* pass any unhandled ceph.* xattrs through to the MDS */
1091         if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
1092                 goto do_sync_unlocked;
1093
1094         prealloc_cf = ceph_alloc_cap_flush();
1095         if (!prealloc_cf)
1096                 return -ENOMEM;
1097
1098         err = -ENOMEM;
1099         spin_lock(&ci->i_ceph_lock);
1100 retry:
1101         issued = __ceph_caps_issued(ci, NULL);
1102         if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
1103                 goto do_sync;
1104
1105         if (!lock_snap_rwsem && !ci->i_head_snapc) {
1106                 lock_snap_rwsem = true;
1107                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
1108                         spin_unlock(&ci->i_ceph_lock);
1109                         down_read(&mdsc->snap_rwsem);
1110                         spin_lock(&ci->i_ceph_lock);
1111                         goto retry;
1112                 }
1113         }
1114
1115         dout("removexattr %p issued %s\n", inode, ceph_cap_string(issued));
1116
1117         __build_xattrs(inode);
1118
1119         required_blob_size = __get_required_blob_size(ci, 0, 0);
1120
1121         if (!ci->i_xattrs.prealloc_blob ||
1122             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
1123                 struct ceph_buffer *blob;
1124
1125                 spin_unlock(&ci->i_ceph_lock);
1126                 dout(" preaallocating new blob size=%d\n", required_blob_size);
1127                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
1128                 if (!blob)
1129                         goto do_sync_unlocked;
1130                 spin_lock(&ci->i_ceph_lock);
1131                 if (ci->i_xattrs.prealloc_blob)
1132                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
1133                 ci->i_xattrs.prealloc_blob = blob;
1134                 goto retry;
1135         }
1136
1137         err = __remove_xattr_by_name(ceph_inode(inode), name);
1138
1139         dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1140                                        &prealloc_cf);
1141         ci->i_xattrs.dirty = true;
1142         inode->i_ctime = CURRENT_TIME;
1143         spin_unlock(&ci->i_ceph_lock);
1144         if (lock_snap_rwsem)
1145                 up_read(&mdsc->snap_rwsem);
1146         if (dirty)
1147                 __mark_inode_dirty(inode, dirty);
1148         ceph_free_cap_flush(prealloc_cf);
1149         return err;
1150 do_sync:
1151         spin_unlock(&ci->i_ceph_lock);
1152 do_sync_unlocked:
1153         if (lock_snap_rwsem)
1154                 up_read(&mdsc->snap_rwsem);
1155         ceph_free_cap_flush(prealloc_cf);
1156         err = ceph_send_removexattr(dentry, name);
1157         return err;
1158 }
1159
1160 int ceph_removexattr(struct dentry *dentry, const char *name)
1161 {
1162         if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
1163                 return -EROFS;
1164
1165         if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
1166                 return generic_removexattr(dentry, name);
1167
1168         return __ceph_removexattr(dentry, name);
1169 }