fs/ceph/xattr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/ceph/ceph_debug.h>
   3 #include <linux/ceph/pagelist.h>
   4
   5 #include "super.h"
   6 #include "mds_client.h"
   7
   8 #include <linux/ceph/decode.h>
   9
  10 #include <linux/xattr.h>
  11 #include <linux/security.h>
  12 #include <linux/posix_acl_xattr.h>
  13 #include <linux/slab.h>
  14
  15 #define XATTR_CEPH_PREFIX "ceph."
  16 #define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)
  17
  18 static int __remove_xattr(struct ceph_inode_info *ci,
  19                           struct ceph_inode_xattr *xattr);
  20
  21 static bool ceph_is_valid_xattr(const char *name)
  22 {
  23         return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
  24                !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
  25                !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
  26 }
  27
  28 /*
  29  * These define virtual xattrs exposing the recursive directory
  30  * statistics and layout metadata.
  31  */
  32 struct ceph_vxattr {
  33         char *name;
  34         size_t name_size;       /* strlen(name) + 1 (for '\0') */
  35         ssize_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
  36                                size_t size);
  37         bool (*exists_cb)(struct ceph_inode_info *ci);
  38         unsigned int flags;
  39 };
  40
  41 #define VXATTR_FLAG_READONLY            (1<<0)
  42 #define VXATTR_FLAG_HIDDEN              (1<<1)
  43 #define VXATTR_FLAG_RSTAT               (1<<2)
  44
  45 /* layouts */
  46
  47 static bool ceph_vxattrcb_layout_exists(struct ceph_inode_info *ci)
  48 {
  49         struct ceph_file_layout *fl = &ci->i_layout;
  50         return (fl->stripe_unit > 0 || fl->stripe_count > 0 ||
  51                 fl->object_size > 0 || fl->pool_id >= 0 ||
  52                 rcu_dereference_raw(fl->pool_ns) != NULL);
  53 }
  54
  55 static ssize_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
  56                                     size_t size)
  57 {
  58         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
  59         struct ceph_osd_client *osdc = &fsc->client->osdc;
  60         struct ceph_string *pool_ns;
  61         s64 pool = ci->i_layout.pool_id;
  62         const char *pool_name;
  63         const char *ns_field = " pool_namespace=";
  64         char buf[128];
  65         size_t len, total_len = 0;
  66         ssize_t ret;
  67
  68         pool_ns = ceph_try_get_string(ci->i_layout.pool_ns);
  69
  70         dout("ceph_vxattrcb_layout %p\n", &ci->vfs_inode);
  71         down_read(&osdc->lock);
  72         pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
  73         if (pool_name) {
  74                 len = snprintf(buf, sizeof(buf),
  75                 "stripe_unit=%u stripe_count=%u object_size=%u pool=",
  76                 ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
  77                 ci->i_layout.object_size);
  78                 total_len = len + strlen(pool_name);
  79         } else {
  80                 len = snprintf(buf, sizeof(buf),
  81                 "stripe_unit=%u stripe_count=%u object_size=%u pool=%lld",
  82                 ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
  83                 ci->i_layout.object_size, pool);
  84                 total_len = len;
  85         }
  86
  87         if (pool_ns)
  88                 total_len += strlen(ns_field) + pool_ns->len;
  89
  90         ret = total_len;
  91         if (size >= total_len) {
  92                 memcpy(val, buf, len);
  93                 ret = len;
  94                 if (pool_name) {
  95                         len = strlen(pool_name);
  96                         memcpy(val + ret, pool_name, len);
  97                         ret += len;
  98                 }
  99                 if (pool_ns) {
 100                         len = strlen(ns_field);
 101                         memcpy(val + ret, ns_field, len);
 102                         ret += len;
 103                         memcpy(val + ret, pool_ns->str, pool_ns->len);
 104                         ret += pool_ns->len;
 105                 }
 106         }
 107         up_read(&osdc->lock);
 108         ceph_put_string(pool_ns);
 109         return ret;
 110 }
 111
 112 /*
 113  * The convention with strings in xattrs is that they should not be NULL
 114  * terminated, since we're returning the length with them. snprintf always
 115  * NULL terminates however, so call it on a temporary buffer and then memcpy
 116  * the result into place.
 117  */
 118 static int ceph_fmt_xattr(char *val, size_t size, const char *fmt, ...)
 119 {
 120         int ret;
 121         va_list args;
 122         char buf[96]; /* NB: reevaluate size if new vxattrs are added */
 123
 124         va_start(args, fmt);
 125         ret = vsnprintf(buf, size ? sizeof(buf) : 0, fmt, args);
 126         va_end(args);
 127
 128         /* Sanity check */
 129         if (size && ret + 1 > sizeof(buf)) {
 130                 WARN_ONCE(true, "Returned length too big (%d)", ret);
 131                 return -E2BIG;
 132         }
 133
 134         if (ret <= size)
 135                 memcpy(val, buf, ret);
 136         return ret;
 137 }
 138
 139 static ssize_t ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info *ci,
 140                                                 char *val, size_t size)
 141 {
 142         return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_unit);
 143 }
 144
 145 static ssize_t ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info *ci,
 146                                                  char *val, size_t size)
 147 {
 148         return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_count);
 149 }
 150
 151 static ssize_t ceph_vxattrcb_layout_object_size(struct ceph_inode_info *ci,
 152                                                 char *val, size_t size)
 153 {
 154         return ceph_fmt_xattr(val, size, "%u", ci->i_layout.object_size);
 155 }
 156
 157 static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
 158                                          char *val, size_t size)
 159 {
 160         ssize_t ret;
 161         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
 162         struct ceph_osd_client *osdc = &fsc->client->osdc;
 163         s64 pool = ci->i_layout.pool_id;
 164         const char *pool_name;
 165
 166         down_read(&osdc->lock);
 167         pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
 168         if (pool_name) {
 169                 ret = strlen(pool_name);
 170                 if (ret <= size)
 171                         memcpy(val, pool_name, ret);
 172         } else {
 173                 ret = ceph_fmt_xattr(val, size, "%lld", pool);
 174         }
 175         up_read(&osdc->lock);
 176         return ret;
 177 }
 178
 179 static ssize_t ceph_vxattrcb_layout_pool_namespace(struct ceph_inode_info *ci,
 180                                                    char *val, size_t size)
 181 {
 182         ssize_t ret = 0;
 183         struct ceph_string *ns = ceph_try_get_string(ci->i_layout.pool_ns);
 184
 185         if (ns) {
 186                 ret = ns->len;
 187                 if (ret <= size)
 188                         memcpy(val, ns->str, ret);
 189                 ceph_put_string(ns);
 190         }
 191         return ret;
 192 }
 193
 194 /* directories */
 195
 196 static ssize_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
 197                                          size_t size)
 198 {
 199         return ceph_fmt_xattr(val, size, "%lld", ci->i_files + ci->i_subdirs);
 200 }
 201
 202 static ssize_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
 203                                        size_t size)
 204 {
 205         return ceph_fmt_xattr(val, size, "%lld", ci->i_files);
 206 }
 207
 208 static ssize_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
 209                                          size_t size)
 210 {
 211         return ceph_fmt_xattr(val, size, "%lld", ci->i_subdirs);
 212 }
 213
 214 static ssize_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
 215                                           size_t size)
 216 {
 217         return ceph_fmt_xattr(val, size, "%lld",
 218                                 ci->i_rfiles + ci->i_rsubdirs);
 219 }
 220
 221 static ssize_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
 222                                         size_t size)
 223 {
 224         return ceph_fmt_xattr(val, size, "%lld", ci->i_rfiles);
 225 }
 226
 227 static ssize_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
 228                                           size_t size)
 229 {
 230         return ceph_fmt_xattr(val, size, "%lld", ci->i_rsubdirs);
 231 }
 232
 233 static ssize_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
 234                                         size_t size)
 235 {
 236         return ceph_fmt_xattr(val, size, "%lld", ci->i_rbytes);
 237 }
 238
 239 static ssize_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
 240                                         size_t size)
 241 {
 242         return ceph_fmt_xattr(val, size, "%lld.%09ld", ci->i_rctime.tv_sec,
 243                                 ci->i_rctime.tv_nsec);
 244 }
 245
 246 /* dir pin */
 247 static bool ceph_vxattrcb_dir_pin_exists(struct ceph_inode_info *ci)
 248 {
 249         return ci->i_dir_pin != -ENODATA;
 250 }
 251
 252 static ssize_t ceph_vxattrcb_dir_pin(struct ceph_inode_info *ci, char *val,
 253                                      size_t size)
 254 {
 255         return ceph_fmt_xattr(val, size, "%d", (int)ci->i_dir_pin);
 256 }
 257
 258 /* quotas */
 259 static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci)
 260 {
 261         bool ret = false;
 262         spin_lock(&ci->i_ceph_lock);
 263         if ((ci->i_max_files || ci->i_max_bytes) &&
 264             ci->i_vino.snap == CEPH_NOSNAP &&
 265             ci->i_snap_realm &&
 266             ci->i_snap_realm->ino == ci->i_vino.ino)
 267                 ret = true;
 268         spin_unlock(&ci->i_ceph_lock);
 269         return ret;
 270 }
 271
 272 static ssize_t ceph_vxattrcb_quota(struct ceph_inode_info *ci, char *val,
 273                                    size_t size)
 274 {
 275         return ceph_fmt_xattr(val, size, "max_bytes=%llu max_files=%llu",
 276                                 ci->i_max_bytes, ci->i_max_files);
 277 }
 278
 279 static ssize_t ceph_vxattrcb_quota_max_bytes(struct ceph_inode_info *ci,
 280                                              char *val, size_t size)
 281 {
 282         return ceph_fmt_xattr(val, size, "%llu", ci->i_max_bytes);
 283 }
 284
 285 static ssize_t ceph_vxattrcb_quota_max_files(struct ceph_inode_info *ci,
 286                                              char *val, size_t size)
 287 {
 288         return ceph_fmt_xattr(val, size, "%llu", ci->i_max_files);
 289 }
 290
 291 /* snapshots */
 292 static bool ceph_vxattrcb_snap_btime_exists(struct ceph_inode_info *ci)
 293 {
 294         return (ci->i_snap_btime.tv_sec != 0 || ci->i_snap_btime.tv_nsec != 0);
 295 }
 296
 297 static ssize_t ceph_vxattrcb_snap_btime(struct ceph_inode_info *ci, char *val,
 298                                         size_t size)
 299 {
 300         return ceph_fmt_xattr(val, size, "%lld.%09ld", ci->i_snap_btime.tv_sec,
 301                                 ci->i_snap_btime.tv_nsec);
 302 }
 303
 304 #define CEPH_XATTR_NAME(_type, _name)   XATTR_CEPH_PREFIX #_type "." #_name
 305 #define CEPH_XATTR_NAME2(_type, _name, _name2)  \
 306         XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
 307
 308 #define XATTR_NAME_CEPH(_type, _name, _flags)                           \
 309         {                                                               \
 310                 .name = CEPH_XATTR_NAME(_type, _name),                  \
 311                 .name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
 312                 .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
 313                 .exists_cb = NULL,                                      \
 314                 .flags = (VXATTR_FLAG_READONLY | _flags),               \
 315         }
 316 #define XATTR_RSTAT_FIELD(_type, _name)                 \
 317         XATTR_NAME_CEPH(_type, _name, VXATTR_FLAG_RSTAT)
 318 #define XATTR_LAYOUT_FIELD(_type, _name, _field)                        \
 319         {                                                               \
 320                 .name = CEPH_XATTR_NAME2(_type, _name, _field), \
 321                 .name_size = sizeof (CEPH_XATTR_NAME2(_type, _name, _field)), \
 322                 .getxattr_cb = ceph_vxattrcb_ ## _name ## _ ## _field, \
 323                 .exists_cb = ceph_vxattrcb_layout_exists,       \
 324                 .flags = VXATTR_FLAG_HIDDEN,                    \
 325         }
 326 #define XATTR_QUOTA_FIELD(_type, _name)                                 \
 327         {                                                               \
 328                 .name = CEPH_XATTR_NAME(_type, _name),                  \
 329                 .name_size = sizeof(CEPH_XATTR_NAME(_type, _name)),     \
 330                 .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name,   \
 331                 .exists_cb = ceph_vxattrcb_quota_exists,                \
 332                 .flags = VXATTR_FLAG_HIDDEN,                            \
 333         }
 334
 335 static struct ceph_vxattr ceph_dir_vxattrs[] = {
 336         {
 337                 .name = "ceph.dir.layout",
 338                 .name_size = sizeof("ceph.dir.layout"),
 339                 .getxattr_cb = ceph_vxattrcb_layout,
 340                 .exists_cb = ceph_vxattrcb_layout_exists,
 341                 .flags = VXATTR_FLAG_HIDDEN,
 342         },
 343         XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
 344         XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
 345         XATTR_LAYOUT_FIELD(dir, layout, object_size),
 346         XATTR_LAYOUT_FIELD(dir, layout, pool),
 347         XATTR_LAYOUT_FIELD(dir, layout, pool_namespace),
 348         XATTR_NAME_CEPH(dir, entries, 0),
 349         XATTR_NAME_CEPH(dir, files, 0),
 350         XATTR_NAME_CEPH(dir, subdirs, 0),
 351         XATTR_RSTAT_FIELD(dir, rentries),
 352         XATTR_RSTAT_FIELD(dir, rfiles),
 353         XATTR_RSTAT_FIELD(dir, rsubdirs),
 354         XATTR_RSTAT_FIELD(dir, rbytes),
 355         XATTR_RSTAT_FIELD(dir, rctime),
 356         {
 357                 .name = "ceph.dir.pin",
 358                 .name_size = sizeof("ceph.dir.pin"),
 359                 .getxattr_cb = ceph_vxattrcb_dir_pin,
 360                 .exists_cb = ceph_vxattrcb_dir_pin_exists,
 361                 .flags = VXATTR_FLAG_HIDDEN,
 362         },
 363         {
 364                 .name = "ceph.quota",
 365                 .name_size = sizeof("ceph.quota"),
 366                 .getxattr_cb = ceph_vxattrcb_quota,
 367                 .exists_cb = ceph_vxattrcb_quota_exists,
 368                 .flags = VXATTR_FLAG_HIDDEN,
 369         },
 370         XATTR_QUOTA_FIELD(quota, max_bytes),
 371         XATTR_QUOTA_FIELD(quota, max_files),
 372         {
 373                 .name = "ceph.snap.btime",
 374                 .name_size = sizeof("ceph.snap.btime"),
 375                 .getxattr_cb = ceph_vxattrcb_snap_btime,
 376                 .exists_cb = ceph_vxattrcb_snap_btime_exists,
 377                 .flags = VXATTR_FLAG_READONLY,
 378         },
 379         { .name = NULL, 0 }     /* Required table terminator */
 380 };
 381
 382 /* files */
 383
 384 static struct ceph_vxattr ceph_file_vxattrs[] = {
 385         {
 386                 .name = "ceph.file.layout",
 387                 .name_size = sizeof("ceph.file.layout"),
 388                 .getxattr_cb = ceph_vxattrcb_layout,
 389                 .exists_cb = ceph_vxattrcb_layout_exists,
 390                 .flags = VXATTR_FLAG_HIDDEN,
 391         },
 392         XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
 393         XATTR_LAYOUT_FIELD(file, layout, stripe_count),
 394         XATTR_LAYOUT_FIELD(file, layout, object_size),
 395         XATTR_LAYOUT_FIELD(file, layout, pool),
 396         XATTR_LAYOUT_FIELD(file, layout, pool_namespace),
 397         {
 398                 .name = "ceph.snap.btime",
 399                 .name_size = sizeof("ceph.snap.btime"),
 400                 .getxattr_cb = ceph_vxattrcb_snap_btime,
 401                 .exists_cb = ceph_vxattrcb_snap_btime_exists,
 402                 .flags = VXATTR_FLAG_READONLY,
 403         },
 404         { .name = NULL, 0 }     /* Required table terminator */
 405 };
 406
 407 static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
 408 {
 409         if (S_ISDIR(inode->i_mode))
 410                 return ceph_dir_vxattrs;
 411         else if (S_ISREG(inode->i_mode))
 412                 return ceph_file_vxattrs;
 413         return NULL;
 414 }
 415
 416 static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 417                                                 const char *name)
 418 {
 419         struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
 420
 421         if (vxattr) {
 422                 while (vxattr->name) {
 423                         if (!strcmp(vxattr->name, name))
 424                                 return vxattr;
 425                         vxattr++;
 426                 }
 427         }
 428
 429         return NULL;
 430 }
 431
 432 static int __set_xattr(struct ceph_inode_info *ci,
 433                            const char *name, int name_len,
 434                            const char *val, int val_len,
 435                            int flags, int update_xattr,
 436                            struct ceph_inode_xattr **newxattr)
 437 {
 438         struct rb_node **p;
 439         struct rb_node *parent = NULL;
 440         struct ceph_inode_xattr *xattr = NULL;
 441         int c;
 442         int new = 0;
 443
 444         p = &ci->i_xattrs.index.rb_node;
 445         while (*p) {
 446                 parent = *p;
 447                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 448                 c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
 449                 if (c < 0)
 450                         p = &(*p)->rb_left;
 451                 else if (c > 0)
 452                         p = &(*p)->rb_right;
 453                 else {
 454                         if (name_len == xattr->name_len)
 455                                 break;
 456                         else if (name_len < xattr->name_len)
 457                                 p = &(*p)->rb_left;
 458                         else
 459                                 p = &(*p)->rb_right;
 460                 }
 461                 xattr = NULL;
 462         }
 463
 464         if (update_xattr) {
 465                 int err = 0;
 466
 467                 if (xattr && (flags & XATTR_CREATE))
 468                         err = -EEXIST;
 469                 else if (!xattr && (flags & XATTR_REPLACE))
 470                         err = -ENODATA;
 471                 if (err) {
 472                         kfree(name);
 473                         kfree(val);
 474                         kfree(*newxattr);
 475                         return err;
 476                 }
 477                 if (update_xattr < 0) {
 478                         if (xattr)
 479                                 __remove_xattr(ci, xattr);
 480                         kfree(name);
 481                         kfree(*newxattr);
 482                         return 0;
 483                 }
 484         }
 485
 486         if (!xattr) {
 487                 new = 1;
 488                 xattr = *newxattr;
 489                 xattr->name = name;
 490                 xattr->name_len = name_len;
 491                 xattr->should_free_name = update_xattr;
 492
 493                 ci->i_xattrs.count++;
 494                 dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 495         } else {
 496                 kfree(*newxattr);
 497                 *newxattr = NULL;
 498                 if (xattr->should_free_val)
 499                         kfree((void *)xattr->val);
 500
 501                 if (update_xattr) {
 502                         kfree((void *)name);
 503                         name = xattr->name;
 504                 }
 505                 ci->i_xattrs.names_size -= xattr->name_len;
 506                 ci->i_xattrs.vals_size -= xattr->val_len;
 507         }
 508         ci->i_xattrs.names_size += name_len;
 509         ci->i_xattrs.vals_size += val_len;
 510         if (val)
 511                 xattr->val = val;
 512         else
 513                 xattr->val = "";
 514
 515         xattr->val_len = val_len;
 516         xattr->dirty = update_xattr;
 517         xattr->should_free_val = (val && update_xattr);
 518
 519         if (new) {
 520                 rb_link_node(&xattr->node, parent, p);
 521                 rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 522                 dout("__set_xattr_val p=%p\n", p);
 523         }
 524
 525         dout("__set_xattr_val added %llx.%llx xattr %p %.*s=%.*s\n",
 526              ceph_vinop(&ci->vfs_inode), xattr, name_len, name, val_len, val);
 527
 528         return 0;
 529 }
 530
 531 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 532                            const char *name)
 533 {
 534         struct rb_node **p;
 535         struct rb_node *parent = NULL;
 536         struct ceph_inode_xattr *xattr = NULL;
 537         int name_len = strlen(name);
 538         int c;
 539
 540         p = &ci->i_xattrs.index.rb_node;
 541         while (*p) {
 542                 parent = *p;
 543                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 544                 c = strncmp(name, xattr->name, xattr->name_len);
 545                 if (c == 0 && name_len > xattr->name_len)
 546                         c = 1;
 547                 if (c < 0)
 548                         p = &(*p)->rb_left;
 549                 else if (c > 0)
 550                         p = &(*p)->rb_right;
 551                 else {
 552                         dout("__get_xattr %s: found %.*s\n", name,
 553                              xattr->val_len, xattr->val);
 554                         return xattr;
 555                 }
 556         }
 557
 558         dout("__get_xattr %s: not found\n", name);
 559
 560         return NULL;
 561 }
 562
 563 static void __free_xattr(struct ceph_inode_xattr *xattr)
 564 {
 565         BUG_ON(!xattr);
 566
 567         if (xattr->should_free_name)
 568                 kfree((void *)xattr->name);
 569         if (xattr->should_free_val)
 570                 kfree((void *)xattr->val);
 571
 572         kfree(xattr);
 573 }
 574
 575 static int __remove_xattr(struct ceph_inode_info *ci,
 576                           struct ceph_inode_xattr *xattr)
 577 {
 578         if (!xattr)
 579                 return -ENODATA;
 580
 581         rb_erase(&xattr->node, &ci->i_xattrs.index);
 582
 583         if (xattr->should_free_name)
 584                 kfree((void *)xattr->name);
 585         if (xattr->should_free_val)
 586                 kfree((void *)xattr->val);
 587
 588         ci->i_xattrs.names_size -= xattr->name_len;
 589         ci->i_xattrs.vals_size -= xattr->val_len;
 590         ci->i_xattrs.count--;
 591         kfree(xattr);
 592
 593         return 0;
 594 }
 595
 596 static char *__copy_xattr_names(struct ceph_inode_info *ci,
 597                                 char *dest)
 598 {
 599         struct rb_node *p;
 600         struct ceph_inode_xattr *xattr = NULL;
 601
 602         p = rb_first(&ci->i_xattrs.index);
 603         dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 604
 605         while (p) {
 606                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 607                 memcpy(dest, xattr->name, xattr->name_len);
 608                 dest[xattr->name_len] = '\0';
 609
 610                 dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 611                      xattr->name_len, ci->i_xattrs.names_size);
 612
 613                 dest += xattr->name_len + 1;
 614                 p = rb_next(p);
 615         }
 616
 617         return dest;
 618 }
 619
 620 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 621 {
 622         struct rb_node *p, *tmp;
 623         struct ceph_inode_xattr *xattr = NULL;
 624
 625         p = rb_first(&ci->i_xattrs.index);
 626
 627         dout("__ceph_destroy_xattrs p=%p\n", p);
 628
 629         while (p) {
 630                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 631                 tmp = p;
 632                 p = rb_next(tmp);
 633                 dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 634                      xattr->name_len, xattr->name);
 635                 rb_erase(tmp, &ci->i_xattrs.index);
 636
 637                 __free_xattr(xattr);
 638         }
 639
 640         ci->i_xattrs.names_size = 0;
 641         ci->i_xattrs.vals_size = 0;
 642         ci->i_xattrs.index_version = 0;
 643         ci->i_xattrs.count = 0;
 644         ci->i_xattrs.index = RB_ROOT;
 645 }
 646
 647 static int __build_xattrs(struct inode *inode)
 648         __releases(ci->i_ceph_lock)
 649         __acquires(ci->i_ceph_lock)
 650 {
 651         u32 namelen;
 652         u32 numattr = 0;
 653         void *p, *end;
 654         u32 len;
 655         const char *name, *val;
 656         struct ceph_inode_info *ci = ceph_inode(inode);
 657         int xattr_version;
 658         struct ceph_inode_xattr **xattrs = NULL;
 659         int err = 0;
 660         int i;
 661
 662         dout("__build_xattrs() len=%d\n",
 663              ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 664
 665         if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 666                 return 0; /* already built */
 667
 668         __ceph_destroy_xattrs(ci);
 669
 670 start:
 671         /* updated internal xattr rb tree */
 672         if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 673                 p = ci->i_xattrs.blob->vec.iov_base;
 674                 end = p + ci->i_xattrs.blob->vec.iov_len;
 675                 ceph_decode_32_safe(&p, end, numattr, bad);
 676                 xattr_version = ci->i_xattrs.version;
 677                 spin_unlock(&ci->i_ceph_lock);
 678
 679                 xattrs = kcalloc(numattr, sizeof(struct ceph_inode_xattr *),
 680                                  GFP_NOFS);
 681                 err = -ENOMEM;
 682                 if (!xattrs)
 683                         goto bad_lock;
 684
 685                 for (i = 0; i < numattr; i++) {
 686                         xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 687                                             GFP_NOFS);
 688                         if (!xattrs[i])
 689                                 goto bad_lock;
 690                 }
 691
 692                 spin_lock(&ci->i_ceph_lock);
 693                 if (ci->i_xattrs.version != xattr_version) {
 694                         /* lost a race, retry */
 695                         for (i = 0; i < numattr; i++)
 696                                 kfree(xattrs[i]);
 697                         kfree(xattrs);
 698                         xattrs = NULL;
 699                         goto start;
 700                 }
 701                 err = -EIO;
 702                 while (numattr--) {
 703                         ceph_decode_32_safe(&p, end, len, bad);
 704                         namelen = len;
 705                         name = p;
 706                         p += len;
 707                         ceph_decode_32_safe(&p, end, len, bad);
 708                         val = p;
 709                         p += len;
 710
 711                         err = __set_xattr(ci, name, namelen, val, len,
 712                                           0, 0, &xattrs[numattr]);
 713
 714                         if (err < 0)
 715                                 goto bad;
 716                 }
 717                 kfree(xattrs);
 718         }
 719         ci->i_xattrs.index_version = ci->i_xattrs.version;
 720         ci->i_xattrs.dirty = false;
 721
 722         return err;
 723 bad_lock:
 724         spin_lock(&ci->i_ceph_lock);
 725 bad:
 726         if (xattrs) {
 727                 for (i = 0; i < numattr; i++)
 728                         kfree(xattrs[i]);
 729                 kfree(xattrs);
 730         }
 731         ci->i_xattrs.names_size = 0;
 732         return err;
 733 }
 734
 735 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 736                                     int val_size)
 737 {
 738         /*
 739          * 4 bytes for the length, and additional 4 bytes per each xattr name,
 740          * 4 bytes per each value
 741          */
 742         int size = 4 + ci->i_xattrs.count*(4 + 4) +
 743                              ci->i_xattrs.names_size +
 744                              ci->i_xattrs.vals_size;
 745         dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 746              ci->i_xattrs.count, ci->i_xattrs.names_size,
 747              ci->i_xattrs.vals_size);
 748
 749         if (name_size)
 750                 size += 4 + 4 + name_size + val_size;
 751
 752         return size;
 753 }
 754
 755 /*
 756  * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 757  * and swap into place.
 758  */
 759 void __ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 760 {
 761         struct rb_node *p;
 762         struct ceph_inode_xattr *xattr = NULL;
 763         void *dest;
 764
 765         dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 766         if (ci->i_xattrs.dirty) {
 767                 int need = __get_required_blob_size(ci, 0, 0);
 768
 769                 BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 770
 771                 p = rb_first(&ci->i_xattrs.index);
 772                 dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 773
 774                 ceph_encode_32(&dest, ci->i_xattrs.count);
 775                 while (p) {
 776                         xattr = rb_entry(p, struct ceph_inode_xattr, node);
 777
 778                         ceph_encode_32(&dest, xattr->name_len);
 779                         memcpy(dest, xattr->name, xattr->name_len);
 780                         dest += xattr->name_len;
 781                         ceph_encode_32(&dest, xattr->val_len);
 782                         memcpy(dest, xattr->val, xattr->val_len);
 783                         dest += xattr->val_len;
 784
 785                         p = rb_next(p);
 786                 }
 787
 788                 /* adjust buffer len; it may be larger than we need */
 789                 ci->i_xattrs.prealloc_blob->vec.iov_len =
 790                         dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 791
 792                 if (ci->i_xattrs.blob)
 793                         ceph_buffer_put(ci->i_xattrs.blob);
 794                 ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 795                 ci->i_xattrs.prealloc_blob = NULL;
 796                 ci->i_xattrs.dirty = false;
 797                 ci->i_xattrs.version++;
 798         }
 799 }
 800
 801 static inline int __get_request_mask(struct inode *in) {
 802         struct ceph_mds_request *req = current->journal_info;
 803         int mask = 0;
 804         if (req && req->r_target_inode == in) {
 805                 if (req->r_op == CEPH_MDS_OP_LOOKUP ||
 806                     req->r_op == CEPH_MDS_OP_LOOKUPINO ||
 807                     req->r_op == CEPH_MDS_OP_LOOKUPPARENT ||
 808                     req->r_op == CEPH_MDS_OP_GETATTR) {
 809                         mask = le32_to_cpu(req->r_args.getattr.mask);
 810                 } else if (req->r_op == CEPH_MDS_OP_OPEN ||
 811                            req->r_op == CEPH_MDS_OP_CREATE) {
 812                         mask = le32_to_cpu(req->r_args.open.mask);
 813                 }
 814         }
 815         return mask;
 816 }
 817
 818 ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 819                       size_t size)
 820 {
 821         struct ceph_inode_info *ci = ceph_inode(inode);
 822         struct ceph_inode_xattr *xattr;
 823         struct ceph_vxattr *vxattr = NULL;
 824         int req_mask;
 825         ssize_t err;
 826
 827         /* let's see if a virtual xattr was requested */
 828         vxattr = ceph_match_vxattr(inode, name);
 829         if (vxattr) {
 830                 int mask = 0;
 831                 if (vxattr->flags & VXATTR_FLAG_RSTAT)
 832                         mask |= CEPH_STAT_RSTAT;
 833                 err = ceph_do_getattr(inode, mask, true);
 834                 if (err)
 835                         return err;
 836                 err = -ENODATA;
 837                 if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
 838                         err = vxattr->getxattr_cb(ci, value, size);
 839                         if (size && size < err)
 840                                 err = -ERANGE;
 841                 }
 842                 return err;
 843         }
 844
 845         req_mask = __get_request_mask(inode);
 846
 847         spin_lock(&ci->i_ceph_lock);
 848         dout("getxattr %p ver=%lld index_ver=%lld\n", inode,
 849              ci->i_xattrs.version, ci->i_xattrs.index_version);
 850
 851         if (ci->i_xattrs.version == 0 ||
 852             !((req_mask & CEPH_CAP_XATTR_SHARED) ||
 853               __ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1))) {
 854                 spin_unlock(&ci->i_ceph_lock);
 855
 856                 /* security module gets xattr while filling trace */
 857                 if (current->journal_info) {
 858                         pr_warn_ratelimited("sync getxattr %p "
 859                                             "during filling trace\n", inode);
 860                         return -EBUSY;
 861                 }
 862
 863                 /* get xattrs from mds (if we don't already have them) */
 864                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 865                 if (err)
 866                         return err;
 867                 spin_lock(&ci->i_ceph_lock);
 868         }
 869
 870         err = __build_xattrs(inode);
 871         if (err < 0)
 872                 goto out;
 873
 874         err = -ENODATA;  /* == ENOATTR */
 875         xattr = __get_xattr(ci, name);
 876         if (!xattr)
 877                 goto out;
 878
 879         err = -ERANGE;
 880         if (size && size < xattr->val_len)
 881                 goto out;
 882
 883         err = xattr->val_len;
 884         if (size == 0)
 885                 goto out;
 886
 887         memcpy(value, xattr->val, xattr->val_len);
 888
 889         if (current->journal_info &&
 890             !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN))
 891                 ci->i_ceph_flags |= CEPH_I_SEC_INITED;
 892 out:
 893         spin_unlock(&ci->i_ceph_lock);
 894         return err;
 895 }
 896
 897 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 898 {
 899         struct inode *inode = d_inode(dentry);
 900         struct ceph_inode_info *ci = ceph_inode(inode);
 901         struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
 902         bool len_only = (size == 0);
 903         u32 namelen;
 904         int err;
 905         int i;
 906
 907         spin_lock(&ci->i_ceph_lock);
 908         dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
 909              ci->i_xattrs.version, ci->i_xattrs.index_version);
 910
 911         if (ci->i_xattrs.version == 0 ||
 912             !__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
 913                 spin_unlock(&ci->i_ceph_lock);
 914                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 915                 if (err)
 916                         return err;
 917                 spin_lock(&ci->i_ceph_lock);
 918         }
 919
 920         err = __build_xattrs(inode);
 921         if (err < 0)
 922                 goto out;
 923
 924         /* add 1 byte for each xattr due to the null termination */
 925         namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
 926         if (!len_only) {
 927                 if (namelen > size) {
 928                         err = -ERANGE;
 929                         goto out;
 930                 }
 931                 names = __copy_xattr_names(ci, names);
 932                 size -= namelen;
 933         }
 934
 935
 936         /* virtual xattr names, too */
 937         if (vxattrs) {
 938                 for (i = 0; vxattrs[i].name; i++) {
 939                         size_t this_len;
 940
 941                         if (vxattrs[i].flags & VXATTR_FLAG_HIDDEN)
 942                                 continue;
 943                         if (vxattrs[i].exists_cb && !vxattrs[i].exists_cb(ci))
 944                                 continue;
 945
 946                         this_len = strlen(vxattrs[i].name) + 1;
 947                         namelen += this_len;
 948                         if (len_only)
 949                                 continue;
 950
 951                         if (this_len > size) {
 952                                 err = -ERANGE;
 953                                 goto out;
 954                         }
 955
 956                         memcpy(names, vxattrs[i].name, this_len);
 957                         names += this_len;
 958                         size -= this_len;
 959                 }
 960         }
 961         err = namelen;
 962 out:
 963         spin_unlock(&ci->i_ceph_lock);
 964         return err;
 965 }
 966
 967 static int ceph_sync_setxattr(struct inode *inode, const char *name,
 968                               const char *value, size_t size, int flags)
 969 {
 970         struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 971         struct ceph_inode_info *ci = ceph_inode(inode);
 972         struct ceph_mds_request *req;
 973         struct ceph_mds_client *mdsc = fsc->mdsc;
 974         struct ceph_pagelist *pagelist = NULL;
 975         int op = CEPH_MDS_OP_SETXATTR;
 976         int err;
 977
 978         if (size > 0) {
 979                 /* copy value into pagelist */
 980                 pagelist = ceph_pagelist_alloc(GFP_NOFS);
 981                 if (!pagelist)
 982                         return -ENOMEM;
 983
 984                 err = ceph_pagelist_append(pagelist, value, size);
 985                 if (err)
 986                         goto out;
 987         } else if (!value) {
 988                 if (flags & CEPH_XATTR_REPLACE)
 989                         op = CEPH_MDS_OP_RMXATTR;
 990                 else
 991                         flags |= CEPH_XATTR_REMOVE;
 992         }
 993
 994         dout("setxattr value=%.*s\n", (int)size, value);
 995
 996         /* do request */
 997         req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 998         if (IS_ERR(req)) {
 999                 err = PTR_ERR(req);
1000                 goto out;
1001         }
1002
1003         req->r_path2 = kstrdup(name, GFP_NOFS);
1004         if (!req->r_path2) {
1005                 ceph_mdsc_put_request(req);
1006                 err = -ENOMEM;
1007                 goto out;
1008         }
1009
1010         if (op == CEPH_MDS_OP_SETXATTR) {
1011                 req->r_args.setxattr.flags = cpu_to_le32(flags);
1012                 req->r_pagelist = pagelist;
1013                 pagelist = NULL;
1014         }
1015
1016         req->r_inode = inode;
1017         ihold(inode);
1018         req->r_num_caps = 1;
1019         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
1020
1021         dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
1022         err = ceph_mdsc_do_request(mdsc, NULL, req);
1023         ceph_mdsc_put_request(req);
1024         dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
1025
1026 out:
1027         if (pagelist)
1028                 ceph_pagelist_release(pagelist);
1029         return err;
1030 }
1031
1032 int __ceph_setxattr(struct inode *inode, const char *name,
1033                         const void *value, size_t size, int flags)
1034 {
1035         struct ceph_vxattr *vxattr;
1036         struct ceph_inode_info *ci = ceph_inode(inode);
1037         struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1038         struct ceph_cap_flush *prealloc_cf = NULL;
1039         int issued;
1040         int err;
1041         int dirty = 0;
1042         int name_len = strlen(name);
1043         int val_len = size;
1044         char *newname = NULL;
1045         char *newval = NULL;
1046         struct ceph_inode_xattr *xattr = NULL;
1047         int required_blob_size;
1048         bool check_realm = false;
1049         bool lock_snap_rwsem = false;
1050
1051         if (ceph_snap(inode) != CEPH_NOSNAP)
1052                 return -EROFS;
1053
1054         vxattr = ceph_match_vxattr(inode, name);
1055         if (vxattr) {
1056                 if (vxattr->flags & VXATTR_FLAG_READONLY)
1057                         return -EOPNOTSUPP;
1058                 if (value && !strncmp(vxattr->name, "ceph.quota", 10))
1059                         check_realm = true;
1060         }
1061
1062         /* pass any unhandled ceph.* xattrs through to the MDS */
1063         if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
1064                 goto do_sync_unlocked;
1065
1066         /* preallocate memory for xattr name, value, index node */
1067         err = -ENOMEM;
1068         newname = kmemdup(name, name_len + 1, GFP_NOFS);
1069         if (!newname)
1070                 goto out;
1071
1072         if (val_len) {
1073                 newval = kmemdup(value, val_len, GFP_NOFS);
1074                 if (!newval)
1075                         goto out;
1076         }
1077
1078         xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
1079         if (!xattr)
1080                 goto out;
1081
1082         prealloc_cf = ceph_alloc_cap_flush();
1083         if (!prealloc_cf)
1084                 goto out;
1085
1086         spin_lock(&ci->i_ceph_lock);
1087 retry:
1088         issued = __ceph_caps_issued(ci, NULL);
1089         if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
1090                 goto do_sync;
1091
1092         if (!lock_snap_rwsem && !ci->i_head_snapc) {
1093                 lock_snap_rwsem = true;
1094                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
1095                         spin_unlock(&ci->i_ceph_lock);
1096                         down_read(&mdsc->snap_rwsem);
1097                         spin_lock(&ci->i_ceph_lock);
1098                         goto retry;
1099                 }
1100         }
1101
1102         dout("setxattr %p issued %s\n", inode, ceph_cap_string(issued));
1103         __build_xattrs(inode);
1104
1105         required_blob_size = __get_required_blob_size(ci, name_len, val_len);
1106
1107         if (!ci->i_xattrs.prealloc_blob ||
1108             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
1109                 struct ceph_buffer *blob;
1110
1111                 spin_unlock(&ci->i_ceph_lock);
1112                 dout(" preaallocating new blob size=%d\n", required_blob_size);
1113                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
1114                 if (!blob)
1115                         goto do_sync_unlocked;
1116                 spin_lock(&ci->i_ceph_lock);
1117                 if (ci->i_xattrs.prealloc_blob)
1118                         ceph_buffer_put(ci->i_xattrs.prealloc_blob);
1119                 ci->i_xattrs.prealloc_blob = blob;
1120                 goto retry;
1121         }
1122
1123         err = __set_xattr(ci, newname, name_len, newval, val_len,
1124                           flags, value ? 1 : -1, &xattr);
1125
1126         if (!err) {
1127                 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1128                                                &prealloc_cf);
1129                 ci->i_xattrs.dirty = true;
1130                 inode->i_ctime = current_time(inode);
1131         }
1132
1133         spin_unlock(&ci->i_ceph_lock);
1134         if (lock_snap_rwsem)
1135                 up_read(&mdsc->snap_rwsem);
1136         if (dirty)
1137                 __mark_inode_dirty(inode, dirty);
1138         ceph_free_cap_flush(prealloc_cf);
1139         return err;
1140
1141 do_sync:
1142         spin_unlock(&ci->i_ceph_lock);
1143 do_sync_unlocked:
1144         if (lock_snap_rwsem)
1145                 up_read(&mdsc->snap_rwsem);
1146
1147         /* security module set xattr while filling trace */
1148         if (current->journal_info) {
1149                 pr_warn_ratelimited("sync setxattr %p "
1150                                     "during filling trace\n", inode);
1151                 err = -EBUSY;
1152         } else {
1153                 err = ceph_sync_setxattr(inode, name, value, size, flags);
1154                 if (err >= 0 && check_realm) {
1155                         /* check if snaprealm was created for quota inode */
1156                         spin_lock(&ci->i_ceph_lock);
1157                         if ((ci->i_max_files || ci->i_max_bytes) &&
1158                             !(ci->i_snap_realm &&
1159                               ci->i_snap_realm->ino == ci->i_vino.ino))
1160                                 err = -EOPNOTSUPP;
1161                         spin_unlock(&ci->i_ceph_lock);
1162                 }
1163         }
1164 out:
1165         ceph_free_cap_flush(prealloc_cf);
1166         kfree(newname);
1167         kfree(newval);
1168         kfree(xattr);
1169         return err;
1170 }
1171
1172 static int ceph_get_xattr_handler(const struct xattr_handler *handler,
1173                                   struct dentry *dentry, struct inode *inode,
1174                                   const char *name, void *value, size_t size)
1175 {
1176         if (!ceph_is_valid_xattr(name))
1177                 return -EOPNOTSUPP;
1178         return __ceph_getxattr(inode, name, value, size);
1179 }
1180
1181 static int ceph_set_xattr_handler(const struct xattr_handler *handler,
1182                                   struct dentry *unused, struct inode *inode,
1183                                   const char *name, const void *value,
1184                                   size_t size, int flags)
1185 {
1186         if (!ceph_is_valid_xattr(name))
1187                 return -EOPNOTSUPP;
1188         return __ceph_setxattr(inode, name, value, size, flags);
1189 }
1190
1191 static const struct xattr_handler ceph_other_xattr_handler = {
1192         .prefix = "",  /* match any name => handlers called with full name */
1193         .get = ceph_get_xattr_handler,
1194         .set = ceph_set_xattr_handler,
1195 };
1196
1197 #ifdef CONFIG_SECURITY
1198 bool ceph_security_xattr_wanted(struct inode *in)
1199 {
1200         return in->i_security != NULL;
1201 }
1202
1203 bool ceph_security_xattr_deadlock(struct inode *in)
1204 {
1205         struct ceph_inode_info *ci;
1206         bool ret;
1207         if (!in->i_security)
1208                 return false;
1209         ci = ceph_inode(in);
1210         spin_lock(&ci->i_ceph_lock);
1211         ret = !(ci->i_ceph_flags & CEPH_I_SEC_INITED) &&
1212               !(ci->i_xattrs.version > 0 &&
1213                 __ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0));
1214         spin_unlock(&ci->i_ceph_lock);
1215         return ret;
1216 }
1217
1218 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1219 int ceph_security_init_secctx(struct dentry *dentry, umode_t mode,
1220                            struct ceph_acl_sec_ctx *as_ctx)
1221 {
1222         struct ceph_pagelist *pagelist = as_ctx->pagelist;
1223         const char *name;
1224         size_t name_len;
1225         int err;
1226
1227         err = security_dentry_init_security(dentry, mode, &dentry->d_name,
1228                                             &as_ctx->sec_ctx,
1229                                             &as_ctx->sec_ctxlen);
1230         if (err < 0) {
1231                 WARN_ON_ONCE(err != -EOPNOTSUPP);
1232                 err = 0; /* do nothing */
1233                 goto out;
1234         }
1235
1236         err = -ENOMEM;
1237         if (!pagelist) {
1238                 pagelist = ceph_pagelist_alloc(GFP_KERNEL);
1239                 if (!pagelist)
1240                         goto out;
1241                 err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
1242                 if (err)
1243                         goto out;
1244                 ceph_pagelist_encode_32(pagelist, 1);
1245         }
1246
1247         /*
1248          * FIXME: Make security_dentry_init_security() generic. Currently
1249          * It only supports single security module and only selinux has
1250          * dentry_init_security hook.
1251          */
1252         name = XATTR_NAME_SELINUX;
1253         name_len = strlen(name);
1254         err = ceph_pagelist_reserve(pagelist,
1255                                     4 * 2 + name_len + as_ctx->sec_ctxlen);
1256         if (err)
1257                 goto out;
1258
1259         if (as_ctx->pagelist) {
1260                 /* update count of KV pairs */
1261                 BUG_ON(pagelist->length <= sizeof(__le32));
1262                 if (list_is_singular(&pagelist->head)) {
1263                         le32_add_cpu((__le32*)pagelist->mapped_tail, 1);
1264                 } else {
1265                         struct page *page = list_first_entry(&pagelist->head,
1266                                                              struct page, lru);
1267                         void *addr = kmap_atomic(page);
1268                         le32_add_cpu((__le32*)addr, 1);
1269                         kunmap_atomic(addr);
1270                 }
1271         } else {
1272                 as_ctx->pagelist = pagelist;
1273         }
1274
1275         ceph_pagelist_encode_32(pagelist, name_len);
1276         ceph_pagelist_append(pagelist, name, name_len);
1277
1278         ceph_pagelist_encode_32(pagelist, as_ctx->sec_ctxlen);
1279         ceph_pagelist_append(pagelist, as_ctx->sec_ctx, as_ctx->sec_ctxlen);
1280
1281         err = 0;
1282 out:
1283         if (pagelist && !as_ctx->pagelist)
1284                 ceph_pagelist_release(pagelist);
1285         return err;
1286 }
1287
1288 void ceph_security_invalidate_secctx(struct inode *inode)
1289 {
1290         security_inode_invalidate_secctx(inode);
1291 }
1292
1293 static int ceph_xattr_set_security_label(const struct xattr_handler *handler,
1294                                     struct dentry *unused, struct inode *inode,
1295                                     const char *key, const void *buf,
1296                                     size_t buflen, int flags)
1297 {
1298         if (security_ismaclabel(key)) {
1299                 const char *name = xattr_full_name(handler, key);
1300                 return __ceph_setxattr(inode, name, buf, buflen, flags);
1301         }
1302         return  -EOPNOTSUPP;
1303 }
1304
1305 static int ceph_xattr_get_security_label(const struct xattr_handler *handler,
1306                                     struct dentry *unused, struct inode *inode,
1307                                     const char *key, void *buf, size_t buflen)
1308 {
1309         if (security_ismaclabel(key)) {
1310                 const char *name = xattr_full_name(handler, key);
1311                 return __ceph_getxattr(inode, name, buf, buflen);
1312         }
1313         return  -EOPNOTSUPP;
1314 }
1315
1316 static const struct xattr_handler ceph_security_label_handler = {
1317         .prefix = XATTR_SECURITY_PREFIX,
1318         .get    = ceph_xattr_get_security_label,
1319         .set    = ceph_xattr_set_security_label,
1320 };
1321 #endif
1322 #endif
1323
1324 void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx)
1325 {
1326 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1327         posix_acl_release(as_ctx->acl);
1328         posix_acl_release(as_ctx->default_acl);
1329 #endif
1330 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1331         security_release_secctx(as_ctx->sec_ctx, as_ctx->sec_ctxlen);
1332 #endif
1333         if (as_ctx->pagelist)
1334                 ceph_pagelist_release(as_ctx->pagelist);
1335 }
1336
1337 /*
1338  * List of handlers for synthetic system.* attributes. Other
1339  * attributes are handled directly.
1340  */
1341 const struct xattr_handler *ceph_xattr_handlers[] = {
1342 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1343         &posix_acl_access_xattr_handler,
1344         &posix_acl_default_xattr_handler,
1345 #endif
1346 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1347         &ceph_security_label_handler,
1348 #endif
1349         &ceph_other_xattr_handler,
1350         NULL,
1351 };