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