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_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) ||
  24                !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
  25                !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
  26                !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
  27 }
  28
  29 /*
  30  * These define virtual xattrs exposing the recursive directory
  31  * statistics and layout metadata.
  32  */
  33 struct ceph_vxattr {
  34         char *name;
  35         size_t name_size;       /* strlen(name) + 1 (for '\0') */
  36         ssize_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
  37                                size_t size);
  38         bool (*exists_cb)(struct ceph_inode_info *ci);
  39         unsigned int flags;
  40 };
  41
  42 #define VXATTR_FLAG_READONLY            (1<<0)
  43 #define VXATTR_FLAG_HIDDEN              (1<<1)
  44 #define VXATTR_FLAG_RSTAT               (1<<2)
  45 #define VXATTR_FLAG_DIRSTAT             (1<<3)
  46
  47 /* layouts */
  48
  49 static bool ceph_vxattrcb_layout_exists(struct ceph_inode_info *ci)
  50 {
  51         struct ceph_file_layout *fl = &ci->i_layout;
  52         return (fl->stripe_unit > 0 || fl->stripe_count > 0 ||
  53                 fl->object_size > 0 || fl->pool_id >= 0 ||
  54                 rcu_dereference_raw(fl->pool_ns) != NULL);
  55 }
  56
  57 static ssize_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
  58                                     size_t size)
  59 {
  60         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
  61         struct ceph_osd_client *osdc = &fsc->client->osdc;
  62         struct ceph_string *pool_ns;
  63         s64 pool = ci->i_layout.pool_id;
  64         const char *pool_name;
  65         const char *ns_field = " pool_namespace=";
  66         char buf[128];
  67         size_t len, total_len = 0;
  68         ssize_t ret;
  69
  70         pool_ns = ceph_try_get_string(ci->i_layout.pool_ns);
  71
  72         dout("ceph_vxattrcb_layout %p\n", &ci->vfs_inode);
  73         down_read(&osdc->lock);
  74         pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
  75         if (pool_name) {
  76                 len = snprintf(buf, sizeof(buf),
  77                 "stripe_unit=%u stripe_count=%u object_size=%u pool=",
  78                 ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
  79                 ci->i_layout.object_size);
  80                 total_len = len + strlen(pool_name);
  81         } else {
  82                 len = snprintf(buf, sizeof(buf),
  83                 "stripe_unit=%u stripe_count=%u object_size=%u pool=%lld",
  84                 ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
  85                 ci->i_layout.object_size, pool);
  86                 total_len = len;
  87         }
  88
  89         if (pool_ns)
  90                 total_len += strlen(ns_field) + pool_ns->len;
  91
  92         ret = total_len;
  93         if (size >= total_len) {
  94                 memcpy(val, buf, len);
  95                 ret = len;
  96                 if (pool_name) {
  97                         len = strlen(pool_name);
  98                         memcpy(val + ret, pool_name, len);
  99                         ret += len;
 100                 }
 101                 if (pool_ns) {
 102                         len = strlen(ns_field);
 103                         memcpy(val + ret, ns_field, len);
 104                         ret += len;
 105                         memcpy(val + ret, pool_ns->str, pool_ns->len);
 106                         ret += pool_ns->len;
 107                 }
 108         }
 109         up_read(&osdc->lock);
 110         ceph_put_string(pool_ns);
 111         return ret;
 112 }
 113
 114 /*
 115  * The convention with strings in xattrs is that they should not be NULL
 116  * terminated, since we're returning the length with them. snprintf always
 117  * NULL terminates however, so call it on a temporary buffer and then memcpy
 118  * the result into place.
 119  */
 120 static __printf(3, 4)
 121 int ceph_fmt_xattr(char *val, size_t size, const char *fmt, ...)
 122 {
 123         int ret;
 124         va_list args;
 125         char buf[96]; /* NB: reevaluate size if new vxattrs are added */
 126
 127         va_start(args, fmt);
 128         ret = vsnprintf(buf, size ? sizeof(buf) : 0, fmt, args);
 129         va_end(args);
 130
 131         /* Sanity check */
 132         if (size && ret + 1 > sizeof(buf)) {
 133                 WARN_ONCE(true, "Returned length too big (%d)", ret);
 134                 return -E2BIG;
 135         }
 136
 137         if (ret <= size)
 138                 memcpy(val, buf, ret);
 139         return ret;
 140 }
 141
 142 static ssize_t ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info *ci,
 143                                                 char *val, size_t size)
 144 {
 145         return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_unit);
 146 }
 147
 148 static ssize_t ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info *ci,
 149                                                  char *val, size_t size)
 150 {
 151         return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_count);
 152 }
 153
 154 static ssize_t ceph_vxattrcb_layout_object_size(struct ceph_inode_info *ci,
 155                                                 char *val, size_t size)
 156 {
 157         return ceph_fmt_xattr(val, size, "%u", ci->i_layout.object_size);
 158 }
 159
 160 static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
 161                                          char *val, size_t size)
 162 {
 163         ssize_t ret;
 164         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
 165         struct ceph_osd_client *osdc = &fsc->client->osdc;
 166         s64 pool = ci->i_layout.pool_id;
 167         const char *pool_name;
 168
 169         down_read(&osdc->lock);
 170         pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
 171         if (pool_name) {
 172                 ret = strlen(pool_name);
 173                 if (ret <= size)
 174                         memcpy(val, pool_name, ret);
 175         } else {
 176                 ret = ceph_fmt_xattr(val, size, "%lld", pool);
 177         }
 178         up_read(&osdc->lock);
 179         return ret;
 180 }
 181
 182 static ssize_t ceph_vxattrcb_layout_pool_namespace(struct ceph_inode_info *ci,
 183                                                    char *val, size_t size)
 184 {
 185         ssize_t ret = 0;
 186         struct ceph_string *ns = ceph_try_get_string(ci->i_layout.pool_ns);
 187
 188         if (ns) {
 189                 ret = ns->len;
 190                 if (ret <= size)
 191                         memcpy(val, ns->str, ret);
 192                 ceph_put_string(ns);
 193         }
 194         return ret;
 195 }
 196
 197 /* directories */
 198
 199 static ssize_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
 200                                          size_t size)
 201 {
 202         return ceph_fmt_xattr(val, size, "%lld", ci->i_files + ci->i_subdirs);
 203 }
 204
 205 static ssize_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
 206                                        size_t size)
 207 {
 208         return ceph_fmt_xattr(val, size, "%lld", ci->i_files);
 209 }
 210
 211 static ssize_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
 212                                          size_t size)
 213 {
 214         return ceph_fmt_xattr(val, size, "%lld", ci->i_subdirs);
 215 }
 216
 217 static ssize_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
 218                                           size_t size)
 219 {
 220         return ceph_fmt_xattr(val, size, "%lld",
 221                                 ci->i_rfiles + ci->i_rsubdirs);
 222 }
 223
 224 static ssize_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
 225                                         size_t size)
 226 {
 227         return ceph_fmt_xattr(val, size, "%lld", ci->i_rfiles);
 228 }
 229
 230 static ssize_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
 231                                           size_t size)
 232 {
 233         return ceph_fmt_xattr(val, size, "%lld", ci->i_rsubdirs);
 234 }
 235
 236 static ssize_t ceph_vxattrcb_dir_rsnaps(struct ceph_inode_info *ci, char *val,
 237                                           size_t size)
 238 {
 239         return ceph_fmt_xattr(val, size, "%lld", ci->i_rsnaps);
 240 }
 241
 242 static ssize_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
 243                                         size_t size)
 244 {
 245         return ceph_fmt_xattr(val, size, "%lld", ci->i_rbytes);
 246 }
 247
 248 static ssize_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
 249                                         size_t size)
 250 {
 251         return ceph_fmt_xattr(val, size, "%lld.%09ld", ci->i_rctime.tv_sec,
 252                                 ci->i_rctime.tv_nsec);
 253 }
 254
 255 /* dir pin */
 256 static bool ceph_vxattrcb_dir_pin_exists(struct ceph_inode_info *ci)
 257 {
 258         return ci->i_dir_pin != -ENODATA;
 259 }
 260
 261 static ssize_t ceph_vxattrcb_dir_pin(struct ceph_inode_info *ci, char *val,
 262                                      size_t size)
 263 {
 264         return ceph_fmt_xattr(val, size, "%d", (int)ci->i_dir_pin);
 265 }
 266
 267 /* quotas */
 268 static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci)
 269 {
 270         bool ret = false;
 271         spin_lock(&ci->i_ceph_lock);
 272         if ((ci->i_max_files || ci->i_max_bytes) &&
 273             ci->i_vino.snap == CEPH_NOSNAP &&
 274             ci->i_snap_realm &&
 275             ci->i_snap_realm->ino == ci->i_vino.ino)
 276                 ret = true;
 277         spin_unlock(&ci->i_ceph_lock);
 278         return ret;
 279 }
 280
 281 static ssize_t ceph_vxattrcb_quota(struct ceph_inode_info *ci, char *val,
 282                                    size_t size)
 283 {
 284         return ceph_fmt_xattr(val, size, "max_bytes=%llu max_files=%llu",
 285                                 ci->i_max_bytes, ci->i_max_files);
 286 }
 287
 288 static ssize_t ceph_vxattrcb_quota_max_bytes(struct ceph_inode_info *ci,
 289                                              char *val, size_t size)
 290 {
 291         return ceph_fmt_xattr(val, size, "%llu", ci->i_max_bytes);
 292 }
 293
 294 static ssize_t ceph_vxattrcb_quota_max_files(struct ceph_inode_info *ci,
 295                                              char *val, size_t size)
 296 {
 297         return ceph_fmt_xattr(val, size, "%llu", ci->i_max_files);
 298 }
 299
 300 /* snapshots */
 301 static bool ceph_vxattrcb_snap_btime_exists(struct ceph_inode_info *ci)
 302 {
 303         return (ci->i_snap_btime.tv_sec != 0 || ci->i_snap_btime.tv_nsec != 0);
 304 }
 305
 306 static ssize_t ceph_vxattrcb_snap_btime(struct ceph_inode_info *ci, char *val,
 307                                         size_t size)
 308 {
 309         return ceph_fmt_xattr(val, size, "%lld.%09ld", ci->i_snap_btime.tv_sec,
 310                                 ci->i_snap_btime.tv_nsec);
 311 }
 312
 313 static ssize_t ceph_vxattrcb_cluster_fsid(struct ceph_inode_info *ci,
 314                                           char *val, size_t size)
 315 {
 316         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
 317
 318         return ceph_fmt_xattr(val, size, "%pU", &fsc->client->fsid);
 319 }
 320
 321 static ssize_t ceph_vxattrcb_client_id(struct ceph_inode_info *ci,
 322                                        char *val, size_t size)
 323 {
 324         struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
 325
 326         return ceph_fmt_xattr(val, size, "client%lld",
 327                               ceph_client_gid(fsc->client));
 328 }
 329
 330 static ssize_t ceph_vxattrcb_caps(struct ceph_inode_info *ci, char *val,
 331                                         size_t size)
 332 {
 333         int issued;
 334
 335         spin_lock(&ci->i_ceph_lock);
 336         issued = __ceph_caps_issued(ci, NULL);
 337         spin_unlock(&ci->i_ceph_lock);
 338
 339         return ceph_fmt_xattr(val, size, "%s/0x%x",
 340                               ceph_cap_string(issued), issued);
 341 }
 342
 343 static ssize_t ceph_vxattrcb_auth_mds(struct ceph_inode_info *ci,
 344                                        char *val, size_t size)
 345 {
 346         int ret;
 347
 348         spin_lock(&ci->i_ceph_lock);
 349         ret = ceph_fmt_xattr(val, size, "%d",
 350                              ci->i_auth_cap ? ci->i_auth_cap->session->s_mds : -1);
 351         spin_unlock(&ci->i_ceph_lock);
 352         return ret;
 353 }
 354
 355 #define CEPH_XATTR_NAME(_type, _name)   XATTR_CEPH_PREFIX #_type "." #_name
 356 #define CEPH_XATTR_NAME2(_type, _name, _name2)  \
 357         XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
 358
 359 #define XATTR_NAME_CEPH(_type, _name, _flags)                           \
 360         {                                                               \
 361                 .name = CEPH_XATTR_NAME(_type, _name),                  \
 362                 .name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
 363                 .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
 364                 .exists_cb = NULL,                                      \
 365                 .flags = (VXATTR_FLAG_READONLY | _flags),               \
 366         }
 367 #define XATTR_RSTAT_FIELD(_type, _name)                 \
 368         XATTR_NAME_CEPH(_type, _name, VXATTR_FLAG_RSTAT)
 369 #define XATTR_LAYOUT_FIELD(_type, _name, _field)                        \
 370         {                                                               \
 371                 .name = CEPH_XATTR_NAME2(_type, _name, _field), \
 372                 .name_size = sizeof (CEPH_XATTR_NAME2(_type, _name, _field)), \
 373                 .getxattr_cb = ceph_vxattrcb_ ## _name ## _ ## _field, \
 374                 .exists_cb = ceph_vxattrcb_layout_exists,       \
 375                 .flags = VXATTR_FLAG_HIDDEN,                    \
 376         }
 377 #define XATTR_QUOTA_FIELD(_type, _name)                                 \
 378         {                                                               \
 379                 .name = CEPH_XATTR_NAME(_type, _name),                  \
 380                 .name_size = sizeof(CEPH_XATTR_NAME(_type, _name)),     \
 381                 .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name,   \
 382                 .exists_cb = ceph_vxattrcb_quota_exists,                \
 383                 .flags = VXATTR_FLAG_HIDDEN,                            \
 384         }
 385
 386 static struct ceph_vxattr ceph_dir_vxattrs[] = {
 387         {
 388                 .name = "ceph.dir.layout",
 389                 .name_size = sizeof("ceph.dir.layout"),
 390                 .getxattr_cb = ceph_vxattrcb_layout,
 391                 .exists_cb = ceph_vxattrcb_layout_exists,
 392                 .flags = VXATTR_FLAG_HIDDEN,
 393         },
 394         XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
 395         XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
 396         XATTR_LAYOUT_FIELD(dir, layout, object_size),
 397         XATTR_LAYOUT_FIELD(dir, layout, pool),
 398         XATTR_LAYOUT_FIELD(dir, layout, pool_namespace),
 399         XATTR_NAME_CEPH(dir, entries, VXATTR_FLAG_DIRSTAT),
 400         XATTR_NAME_CEPH(dir, files, VXATTR_FLAG_DIRSTAT),
 401         XATTR_NAME_CEPH(dir, subdirs, VXATTR_FLAG_DIRSTAT),
 402         XATTR_RSTAT_FIELD(dir, rentries),
 403         XATTR_RSTAT_FIELD(dir, rfiles),
 404         XATTR_RSTAT_FIELD(dir, rsubdirs),
 405         XATTR_RSTAT_FIELD(dir, rsnaps),
 406         XATTR_RSTAT_FIELD(dir, rbytes),
 407         XATTR_RSTAT_FIELD(dir, rctime),
 408         {
 409                 .name = "ceph.dir.pin",
 410                 .name_size = sizeof("ceph.dir.pin"),
 411                 .getxattr_cb = ceph_vxattrcb_dir_pin,
 412                 .exists_cb = ceph_vxattrcb_dir_pin_exists,
 413                 .flags = VXATTR_FLAG_HIDDEN,
 414         },
 415         {
 416                 .name = "ceph.quota",
 417                 .name_size = sizeof("ceph.quota"),
 418                 .getxattr_cb = ceph_vxattrcb_quota,
 419                 .exists_cb = ceph_vxattrcb_quota_exists,
 420                 .flags = VXATTR_FLAG_HIDDEN,
 421         },
 422         XATTR_QUOTA_FIELD(quota, max_bytes),
 423         XATTR_QUOTA_FIELD(quota, max_files),
 424         {
 425                 .name = "ceph.snap.btime",
 426                 .name_size = sizeof("ceph.snap.btime"),
 427                 .getxattr_cb = ceph_vxattrcb_snap_btime,
 428                 .exists_cb = ceph_vxattrcb_snap_btime_exists,
 429                 .flags = VXATTR_FLAG_READONLY,
 430         },
 431         {
 432                 .name = "ceph.caps",
 433                 .name_size = sizeof("ceph.caps"),
 434                 .getxattr_cb = ceph_vxattrcb_caps,
 435                 .exists_cb = NULL,
 436                 .flags = VXATTR_FLAG_HIDDEN,
 437         },
 438         { .name = NULL, 0 }     /* Required table terminator */
 439 };
 440
 441 /* files */
 442
 443 static struct ceph_vxattr ceph_file_vxattrs[] = {
 444         {
 445                 .name = "ceph.file.layout",
 446                 .name_size = sizeof("ceph.file.layout"),
 447                 .getxattr_cb = ceph_vxattrcb_layout,
 448                 .exists_cb = ceph_vxattrcb_layout_exists,
 449                 .flags = VXATTR_FLAG_HIDDEN,
 450         },
 451         XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
 452         XATTR_LAYOUT_FIELD(file, layout, stripe_count),
 453         XATTR_LAYOUT_FIELD(file, layout, object_size),
 454         XATTR_LAYOUT_FIELD(file, layout, pool),
 455         XATTR_LAYOUT_FIELD(file, layout, pool_namespace),
 456         {
 457                 .name = "ceph.snap.btime",
 458                 .name_size = sizeof("ceph.snap.btime"),
 459                 .getxattr_cb = ceph_vxattrcb_snap_btime,
 460                 .exists_cb = ceph_vxattrcb_snap_btime_exists,
 461                 .flags = VXATTR_FLAG_READONLY,
 462         },
 463         {
 464                 .name = "ceph.caps",
 465                 .name_size = sizeof("ceph.caps"),
 466                 .getxattr_cb = ceph_vxattrcb_caps,
 467                 .exists_cb = NULL,
 468                 .flags = VXATTR_FLAG_HIDDEN,
 469         },
 470         { .name = NULL, 0 }     /* Required table terminator */
 471 };
 472
 473 static struct ceph_vxattr ceph_common_vxattrs[] = {
 474         {
 475                 .name = "ceph.cluster_fsid",
 476                 .name_size = sizeof("ceph.cluster_fsid"),
 477                 .getxattr_cb = ceph_vxattrcb_cluster_fsid,
 478                 .exists_cb = NULL,
 479                 .flags = VXATTR_FLAG_READONLY,
 480         },
 481         {
 482                 .name = "ceph.client_id",
 483                 .name_size = sizeof("ceph.client_id"),
 484                 .getxattr_cb = ceph_vxattrcb_client_id,
 485                 .exists_cb = NULL,
 486                 .flags = VXATTR_FLAG_READONLY,
 487         },
 488         {
 489                 .name = "ceph.auth_mds",
 490                 .name_size = sizeof("ceph.auth_mds"),
 491                 .getxattr_cb = ceph_vxattrcb_auth_mds,
 492                 .exists_cb = NULL,
 493                 .flags = VXATTR_FLAG_READONLY,
 494         },
 495         { .name = NULL, 0 }     /* Required table terminator */
 496 };
 497
 498 static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
 499 {
 500         if (S_ISDIR(inode->i_mode))
 501                 return ceph_dir_vxattrs;
 502         else if (S_ISREG(inode->i_mode))
 503                 return ceph_file_vxattrs;
 504         return NULL;
 505 }
 506
 507 static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 508                                                 const char *name)
 509 {
 510         struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
 511
 512         if (vxattr) {
 513                 while (vxattr->name) {
 514                         if (!strcmp(vxattr->name, name))
 515                                 return vxattr;
 516                         vxattr++;
 517                 }
 518         }
 519
 520         vxattr = ceph_common_vxattrs;
 521         while (vxattr->name) {
 522                 if (!strcmp(vxattr->name, name))
 523                         return vxattr;
 524                 vxattr++;
 525         }
 526
 527         return NULL;
 528 }
 529
 530 static int __set_xattr(struct ceph_inode_info *ci,
 531                            const char *name, int name_len,
 532                            const char *val, int val_len,
 533                            int flags, int update_xattr,
 534                            struct ceph_inode_xattr **newxattr)
 535 {
 536         struct rb_node **p;
 537         struct rb_node *parent = NULL;
 538         struct ceph_inode_xattr *xattr = NULL;
 539         int c;
 540         int new = 0;
 541
 542         p = &ci->i_xattrs.index.rb_node;
 543         while (*p) {
 544                 parent = *p;
 545                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 546                 c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
 547                 if (c < 0)
 548                         p = &(*p)->rb_left;
 549                 else if (c > 0)
 550                         p = &(*p)->rb_right;
 551                 else {
 552                         if (name_len == xattr->name_len)
 553                                 break;
 554                         else if (name_len < xattr->name_len)
 555                                 p = &(*p)->rb_left;
 556                         else
 557                                 p = &(*p)->rb_right;
 558                 }
 559                 xattr = NULL;
 560         }
 561
 562         if (update_xattr) {
 563                 int err = 0;
 564
 565                 if (xattr && (flags & XATTR_CREATE))
 566                         err = -EEXIST;
 567                 else if (!xattr && (flags & XATTR_REPLACE))
 568                         err = -ENODATA;
 569                 if (err) {
 570                         kfree(name);
 571                         kfree(val);
 572                         kfree(*newxattr);
 573                         return err;
 574                 }
 575                 if (update_xattr < 0) {
 576                         if (xattr)
 577                                 __remove_xattr(ci, xattr);
 578                         kfree(name);
 579                         kfree(*newxattr);
 580                         return 0;
 581                 }
 582         }
 583
 584         if (!xattr) {
 585                 new = 1;
 586                 xattr = *newxattr;
 587                 xattr->name = name;
 588                 xattr->name_len = name_len;
 589                 xattr->should_free_name = update_xattr;
 590
 591                 ci->i_xattrs.count++;
 592                 dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 593         } else {
 594                 kfree(*newxattr);
 595                 *newxattr = NULL;
 596                 if (xattr->should_free_val)
 597                         kfree(xattr->val);
 598
 599                 if (update_xattr) {
 600                         kfree(name);
 601                         name = xattr->name;
 602                 }
 603                 ci->i_xattrs.names_size -= xattr->name_len;
 604                 ci->i_xattrs.vals_size -= xattr->val_len;
 605         }
 606         ci->i_xattrs.names_size += name_len;
 607         ci->i_xattrs.vals_size += val_len;
 608         if (val)
 609                 xattr->val = val;
 610         else
 611                 xattr->val = "";
 612
 613         xattr->val_len = val_len;
 614         xattr->dirty = update_xattr;
 615         xattr->should_free_val = (val && update_xattr);
 616
 617         if (new) {
 618                 rb_link_node(&xattr->node, parent, p);
 619                 rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 620                 dout("__set_xattr_val p=%p\n", p);
 621         }
 622
 623         dout("__set_xattr_val added %llx.%llx xattr %p %.*s=%.*s\n",
 624              ceph_vinop(&ci->vfs_inode), xattr, name_len, name, val_len, val);
 625
 626         return 0;
 627 }
 628
 629 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 630                            const char *name)
 631 {
 632         struct rb_node **p;
 633         struct rb_node *parent = NULL;
 634         struct ceph_inode_xattr *xattr = NULL;
 635         int name_len = strlen(name);
 636         int c;
 637
 638         p = &ci->i_xattrs.index.rb_node;
 639         while (*p) {
 640                 parent = *p;
 641                 xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 642                 c = strncmp(name, xattr->name, xattr->name_len);
 643                 if (c == 0 && name_len > xattr->name_len)
 644                         c = 1;
 645                 if (c < 0)
 646                         p = &(*p)->rb_left;
 647                 else if (c > 0)
 648                         p = &(*p)->rb_right;
 649                 else {
 650                         dout("__get_xattr %s: found %.*s\n", name,
 651                              xattr->val_len, xattr->val);
 652                         return xattr;
 653                 }
 654         }
 655
 656         dout("__get_xattr %s: not found\n", name);
 657
 658         return NULL;
 659 }
 660
 661 static void __free_xattr(struct ceph_inode_xattr *xattr)
 662 {
 663         BUG_ON(!xattr);
 664
 665         if (xattr->should_free_name)
 666                 kfree(xattr->name);
 667         if (xattr->should_free_val)
 668                 kfree(xattr->val);
 669
 670         kfree(xattr);
 671 }
 672
 673 static int __remove_xattr(struct ceph_inode_info *ci,
 674                           struct ceph_inode_xattr *xattr)
 675 {
 676         if (!xattr)
 677                 return -ENODATA;
 678
 679         rb_erase(&xattr->node, &ci->i_xattrs.index);
 680
 681         if (xattr->should_free_name)
 682                 kfree(xattr->name);
 683         if (xattr->should_free_val)
 684                 kfree(xattr->val);
 685
 686         ci->i_xattrs.names_size -= xattr->name_len;
 687         ci->i_xattrs.vals_size -= xattr->val_len;
 688         ci->i_xattrs.count--;
 689         kfree(xattr);
 690
 691         return 0;
 692 }
 693
 694 static char *__copy_xattr_names(struct ceph_inode_info *ci,
 695                                 char *dest)
 696 {
 697         struct rb_node *p;
 698         struct ceph_inode_xattr *xattr = NULL;
 699
 700         p = rb_first(&ci->i_xattrs.index);
 701         dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 702
 703         while (p) {
 704                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 705                 memcpy(dest, xattr->name, xattr->name_len);
 706                 dest[xattr->name_len] = '\0';
 707
 708                 dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 709                      xattr->name_len, ci->i_xattrs.names_size);
 710
 711                 dest += xattr->name_len + 1;
 712                 p = rb_next(p);
 713         }
 714
 715         return dest;
 716 }
 717
 718 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 719 {
 720         struct rb_node *p, *tmp;
 721         struct ceph_inode_xattr *xattr = NULL;
 722
 723         p = rb_first(&ci->i_xattrs.index);
 724
 725         dout("__ceph_destroy_xattrs p=%p\n", p);
 726
 727         while (p) {
 728                 xattr = rb_entry(p, struct ceph_inode_xattr, node);
 729                 tmp = p;
 730                 p = rb_next(tmp);
 731                 dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 732                      xattr->name_len, xattr->name);
 733                 rb_erase(tmp, &ci->i_xattrs.index);
 734
 735                 __free_xattr(xattr);
 736         }
 737
 738         ci->i_xattrs.names_size = 0;
 739         ci->i_xattrs.vals_size = 0;
 740         ci->i_xattrs.index_version = 0;
 741         ci->i_xattrs.count = 0;
 742         ci->i_xattrs.index = RB_ROOT;
 743 }
 744
 745 static int __build_xattrs(struct inode *inode)
 746         __releases(ci->i_ceph_lock)
 747         __acquires(ci->i_ceph_lock)
 748 {
 749         u32 namelen;
 750         u32 numattr = 0;
 751         void *p, *end;
 752         u32 len;
 753         const char *name, *val;
 754         struct ceph_inode_info *ci = ceph_inode(inode);
 755         u64 xattr_version;
 756         struct ceph_inode_xattr **xattrs = NULL;
 757         int err = 0;
 758         int i;
 759
 760         dout("__build_xattrs() len=%d\n",
 761              ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 762
 763         if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 764                 return 0; /* already built */
 765
 766         __ceph_destroy_xattrs(ci);
 767
 768 start:
 769         /* updated internal xattr rb tree */
 770         if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 771                 p = ci->i_xattrs.blob->vec.iov_base;
 772                 end = p + ci->i_xattrs.blob->vec.iov_len;
 773                 ceph_decode_32_safe(&p, end, numattr, bad);
 774                 xattr_version = ci->i_xattrs.version;
 775                 spin_unlock(&ci->i_ceph_lock);
 776
 777                 xattrs = kcalloc(numattr, sizeof(struct ceph_inode_xattr *),
 778                                  GFP_NOFS);
 779                 err = -ENOMEM;
 780                 if (!xattrs)
 781                         goto bad_lock;
 782
 783                 for (i = 0; i < numattr; i++) {
 784                         xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 785                                             GFP_NOFS);
 786                         if (!xattrs[i])
 787                                 goto bad_lock;
 788                 }
 789
 790                 spin_lock(&ci->i_ceph_lock);
 791                 if (ci->i_xattrs.version != xattr_version) {
 792                         /* lost a race, retry */
 793                         for (i = 0; i < numattr; i++)
 794                                 kfree(xattrs[i]);
 795                         kfree(xattrs);
 796                         xattrs = NULL;
 797                         goto start;
 798                 }
 799                 err = -EIO;
 800                 while (numattr--) {
 801                         ceph_decode_32_safe(&p, end, len, bad);
 802                         namelen = len;
 803                         name = p;
 804                         p += len;
 805                         ceph_decode_32_safe(&p, end, len, bad);
 806                         val = p;
 807                         p += len;
 808
 809                         err = __set_xattr(ci, name, namelen, val, len,
 810                                           0, 0, &xattrs[numattr]);
 811
 812                         if (err < 0)
 813                                 goto bad;
 814                 }
 815                 kfree(xattrs);
 816         }
 817         ci->i_xattrs.index_version = ci->i_xattrs.version;
 818         ci->i_xattrs.dirty = false;
 819
 820         return err;
 821 bad_lock:
 822         spin_lock(&ci->i_ceph_lock);
 823 bad:
 824         if (xattrs) {
 825                 for (i = 0; i < numattr; i++)
 826                         kfree(xattrs[i]);
 827                 kfree(xattrs);
 828         }
 829         ci->i_xattrs.names_size = 0;
 830         return err;
 831 }
 832
 833 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 834                                     int val_size)
 835 {
 836         /*
 837          * 4 bytes for the length, and additional 4 bytes per each xattr name,
 838          * 4 bytes per each value
 839          */
 840         int size = 4 + ci->i_xattrs.count*(4 + 4) +
 841                              ci->i_xattrs.names_size +
 842                              ci->i_xattrs.vals_size;
 843         dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 844              ci->i_xattrs.count, ci->i_xattrs.names_size,
 845              ci->i_xattrs.vals_size);
 846
 847         if (name_size)
 848                 size += 4 + 4 + name_size + val_size;
 849
 850         return size;
 851 }
 852
 853 /*
 854  * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 855  * and swap into place.  It returns the old i_xattrs.blob (or NULL) so
 856  * that it can be freed by the caller as the i_ceph_lock is likely to be
 857  * held.
 858  */
 859 struct ceph_buffer *__ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 860 {
 861         struct rb_node *p;
 862         struct ceph_inode_xattr *xattr = NULL;
 863         struct ceph_buffer *old_blob = NULL;
 864         void *dest;
 865
 866         dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 867         if (ci->i_xattrs.dirty) {
 868                 int need = __get_required_blob_size(ci, 0, 0);
 869
 870                 BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 871
 872                 p = rb_first(&ci->i_xattrs.index);
 873                 dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 874
 875                 ceph_encode_32(&dest, ci->i_xattrs.count);
 876                 while (p) {
 877                         xattr = rb_entry(p, struct ceph_inode_xattr, node);
 878
 879                         ceph_encode_32(&dest, xattr->name_len);
 880                         memcpy(dest, xattr->name, xattr->name_len);
 881                         dest += xattr->name_len;
 882                         ceph_encode_32(&dest, xattr->val_len);
 883                         memcpy(dest, xattr->val, xattr->val_len);
 884                         dest += xattr->val_len;
 885
 886                         p = rb_next(p);
 887                 }
 888
 889                 /* adjust buffer len; it may be larger than we need */
 890                 ci->i_xattrs.prealloc_blob->vec.iov_len =
 891                         dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 892
 893                 if (ci->i_xattrs.blob)
 894                         old_blob = ci->i_xattrs.blob;
 895                 ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 896                 ci->i_xattrs.prealloc_blob = NULL;
 897                 ci->i_xattrs.dirty = false;
 898                 ci->i_xattrs.version++;
 899         }
 900
 901         return old_blob;
 902 }
 903
 904 static inline int __get_request_mask(struct inode *in) {
 905         struct ceph_mds_request *req = current->journal_info;
 906         int mask = 0;
 907         if (req && req->r_target_inode == in) {
 908                 if (req->r_op == CEPH_MDS_OP_LOOKUP ||
 909                     req->r_op == CEPH_MDS_OP_LOOKUPINO ||
 910                     req->r_op == CEPH_MDS_OP_LOOKUPPARENT ||
 911                     req->r_op == CEPH_MDS_OP_GETATTR) {
 912                         mask = le32_to_cpu(req->r_args.getattr.mask);
 913                 } else if (req->r_op == CEPH_MDS_OP_OPEN ||
 914                            req->r_op == CEPH_MDS_OP_CREATE) {
 915                         mask = le32_to_cpu(req->r_args.open.mask);
 916                 }
 917         }
 918         return mask;
 919 }
 920
 921 ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 922                       size_t size)
 923 {
 924         struct ceph_inode_info *ci = ceph_inode(inode);
 925         struct ceph_inode_xattr *xattr;
 926         struct ceph_vxattr *vxattr = NULL;
 927         int req_mask;
 928         ssize_t err;
 929
 930         /* let's see if a virtual xattr was requested */
 931         vxattr = ceph_match_vxattr(inode, name);
 932         if (vxattr) {
 933                 int mask = 0;
 934                 if (vxattr->flags & VXATTR_FLAG_RSTAT)
 935                         mask |= CEPH_STAT_RSTAT;
 936                 if (vxattr->flags & VXATTR_FLAG_DIRSTAT)
 937                         mask |= CEPH_CAP_FILE_SHARED;
 938                 err = ceph_do_getattr(inode, mask, true);
 939                 if (err)
 940                         return err;
 941                 err = -ENODATA;
 942                 if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
 943                         err = vxattr->getxattr_cb(ci, value, size);
 944                         if (size && size < err)
 945                                 err = -ERANGE;
 946                 }
 947                 return err;
 948         }
 949
 950         req_mask = __get_request_mask(inode);
 951
 952         spin_lock(&ci->i_ceph_lock);
 953         dout("getxattr %p name '%s' ver=%lld index_ver=%lld\n", inode, name,
 954              ci->i_xattrs.version, ci->i_xattrs.index_version);
 955
 956         if (ci->i_xattrs.version == 0 ||
 957             !((req_mask & CEPH_CAP_XATTR_SHARED) ||
 958               __ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1))) {
 959                 spin_unlock(&ci->i_ceph_lock);
 960
 961                 /* security module gets xattr while filling trace */
 962                 if (current->journal_info) {
 963                         pr_warn_ratelimited("sync getxattr %p "
 964                                             "during filling trace\n", inode);
 965                         return -EBUSY;
 966                 }
 967
 968                 /* get xattrs from mds (if we don't already have them) */
 969                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 970                 if (err)
 971                         return err;
 972                 spin_lock(&ci->i_ceph_lock);
 973         }
 974
 975         err = __build_xattrs(inode);
 976         if (err < 0)
 977                 goto out;
 978
 979         err = -ENODATA;  /* == ENOATTR */
 980         xattr = __get_xattr(ci, name);
 981         if (!xattr)
 982                 goto out;
 983
 984         err = -ERANGE;
 985         if (size && size < xattr->val_len)
 986                 goto out;
 987
 988         err = xattr->val_len;
 989         if (size == 0)
 990                 goto out;
 991
 992         memcpy(value, xattr->val, xattr->val_len);
 993
 994         if (current->journal_info &&
 995             !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
 996             security_ismaclabel(name + XATTR_SECURITY_PREFIX_LEN))
 997                 ci->i_ceph_flags |= CEPH_I_SEC_INITED;
 998 out:
 999         spin_unlock(&ci->i_ceph_lock);
1000         return err;
1001 }
1002
1003 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
1004 {
1005         struct inode *inode = d_inode(dentry);
1006         struct ceph_inode_info *ci = ceph_inode(inode);
1007         bool len_only = (size == 0);
1008         u32 namelen;
1009         int err;
1010
1011         spin_lock(&ci->i_ceph_lock);
1012         dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
1013              ci->i_xattrs.version, ci->i_xattrs.index_version);
1014
1015         if (ci->i_xattrs.version == 0 ||
1016             !__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1)) {
1017                 spin_unlock(&ci->i_ceph_lock);
1018                 err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
1019                 if (err)
1020                         return err;
1021                 spin_lock(&ci->i_ceph_lock);
1022         }
1023
1024         err = __build_xattrs(inode);
1025         if (err < 0)
1026                 goto out;
1027
1028         /* add 1 byte for each xattr due to the null termination */
1029         namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
1030         if (!len_only) {
1031                 if (namelen > size) {
1032                         err = -ERANGE;
1033                         goto out;
1034                 }
1035                 names = __copy_xattr_names(ci, names);
1036                 size -= namelen;
1037         }
1038         err = namelen;
1039 out:
1040         spin_unlock(&ci->i_ceph_lock);
1041         return err;
1042 }
1043
1044 static int ceph_sync_setxattr(struct inode *inode, const char *name,
1045                               const char *value, size_t size, int flags)
1046 {
1047         struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
1048         struct ceph_inode_info *ci = ceph_inode(inode);
1049         struct ceph_mds_request *req;
1050         struct ceph_mds_client *mdsc = fsc->mdsc;
1051         struct ceph_osd_client *osdc = &fsc->client->osdc;
1052         struct ceph_pagelist *pagelist = NULL;
1053         int op = CEPH_MDS_OP_SETXATTR;
1054         int err;
1055
1056         if (size > 0) {
1057                 /* copy value into pagelist */
1058                 pagelist = ceph_pagelist_alloc(GFP_NOFS);
1059                 if (!pagelist)
1060                         return -ENOMEM;
1061
1062                 err = ceph_pagelist_append(pagelist, value, size);
1063                 if (err)
1064                         goto out;
1065         } else if (!value) {
1066                 if (flags & CEPH_XATTR_REPLACE)
1067                         op = CEPH_MDS_OP_RMXATTR;
1068                 else
1069                         flags |= CEPH_XATTR_REMOVE;
1070         }
1071
1072         dout("setxattr value=%.*s\n", (int)size, value);
1073
1074         /* do request */
1075         req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1076         if (IS_ERR(req)) {
1077                 err = PTR_ERR(req);
1078                 goto out;
1079         }
1080
1081         req->r_path2 = kstrdup(name, GFP_NOFS);
1082         if (!req->r_path2) {
1083                 ceph_mdsc_put_request(req);
1084                 err = -ENOMEM;
1085                 goto out;
1086         }
1087
1088         if (op == CEPH_MDS_OP_SETXATTR) {
1089                 req->r_args.setxattr.flags = cpu_to_le32(flags);
1090                 req->r_args.setxattr.osdmap_epoch =
1091                         cpu_to_le32(osdc->osdmap->epoch);
1092                 req->r_pagelist = pagelist;
1093                 pagelist = NULL;
1094         }
1095
1096         req->r_inode = inode;
1097         ihold(inode);
1098         req->r_num_caps = 1;
1099         req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
1100
1101         dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
1102         err = ceph_mdsc_do_request(mdsc, NULL, req);
1103         ceph_mdsc_put_request(req);
1104         dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
1105
1106 out:
1107         if (pagelist)
1108                 ceph_pagelist_release(pagelist);
1109         return err;
1110 }
1111
1112 int __ceph_setxattr(struct inode *inode, const char *name,
1113                         const void *value, size_t size, int flags)
1114 {
1115         struct ceph_vxattr *vxattr;
1116         struct ceph_inode_info *ci = ceph_inode(inode);
1117         struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1118         struct ceph_cap_flush *prealloc_cf = NULL;
1119         struct ceph_buffer *old_blob = NULL;
1120         int issued;
1121         int err;
1122         int dirty = 0;
1123         int name_len = strlen(name);
1124         int val_len = size;
1125         char *newname = NULL;
1126         char *newval = NULL;
1127         struct ceph_inode_xattr *xattr = NULL;
1128         int required_blob_size;
1129         bool check_realm = false;
1130         bool lock_snap_rwsem = false;
1131
1132         if (ceph_snap(inode) != CEPH_NOSNAP)
1133                 return -EROFS;
1134
1135         vxattr = ceph_match_vxattr(inode, name);
1136         if (vxattr) {
1137                 if (vxattr->flags & VXATTR_FLAG_READONLY)
1138                         return -EOPNOTSUPP;
1139                 if (value && !strncmp(vxattr->name, "ceph.quota", 10))
1140                         check_realm = true;
1141         }
1142
1143         /* pass any unhandled ceph.* xattrs through to the MDS */
1144         if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
1145                 goto do_sync_unlocked;
1146
1147         /* preallocate memory for xattr name, value, index node */
1148         err = -ENOMEM;
1149         newname = kmemdup(name, name_len + 1, GFP_NOFS);
1150         if (!newname)
1151                 goto out;
1152
1153         if (val_len) {
1154                 newval = kmemdup(value, val_len, GFP_NOFS);
1155                 if (!newval)
1156                         goto out;
1157         }
1158
1159         xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
1160         if (!xattr)
1161                 goto out;
1162
1163         prealloc_cf = ceph_alloc_cap_flush();
1164         if (!prealloc_cf)
1165                 goto out;
1166
1167         spin_lock(&ci->i_ceph_lock);
1168 retry:
1169         issued = __ceph_caps_issued(ci, NULL);
1170         if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
1171                 goto do_sync;
1172
1173         if (!lock_snap_rwsem && !ci->i_head_snapc) {
1174                 lock_snap_rwsem = true;
1175                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
1176                         spin_unlock(&ci->i_ceph_lock);
1177                         down_read(&mdsc->snap_rwsem);
1178                         spin_lock(&ci->i_ceph_lock);
1179                         goto retry;
1180                 }
1181         }
1182
1183         dout("setxattr %p name '%s' issued %s\n", inode, name,
1184              ceph_cap_string(issued));
1185         __build_xattrs(inode);
1186
1187         required_blob_size = __get_required_blob_size(ci, name_len, val_len);
1188
1189         if (!ci->i_xattrs.prealloc_blob ||
1190             required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
1191                 struct ceph_buffer *blob;
1192
1193                 spin_unlock(&ci->i_ceph_lock);
1194                 ceph_buffer_put(old_blob); /* Shouldn't be required */
1195                 dout(" pre-allocating new blob size=%d\n", required_blob_size);
1196                 blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
1197                 if (!blob)
1198                         goto do_sync_unlocked;
1199                 spin_lock(&ci->i_ceph_lock);
1200                 /* prealloc_blob can't be released while holding i_ceph_lock */
1201                 if (ci->i_xattrs.prealloc_blob)
1202                         old_blob = ci->i_xattrs.prealloc_blob;
1203                 ci->i_xattrs.prealloc_blob = blob;
1204                 goto retry;
1205         }
1206
1207         err = __set_xattr(ci, newname, name_len, newval, val_len,
1208                           flags, value ? 1 : -1, &xattr);
1209
1210         if (!err) {
1211                 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1212                                                &prealloc_cf);
1213                 ci->i_xattrs.dirty = true;
1214                 inode->i_ctime = current_time(inode);
1215         }
1216
1217         spin_unlock(&ci->i_ceph_lock);
1218         ceph_buffer_put(old_blob);
1219         if (lock_snap_rwsem)
1220                 up_read(&mdsc->snap_rwsem);
1221         if (dirty)
1222                 __mark_inode_dirty(inode, dirty);
1223         ceph_free_cap_flush(prealloc_cf);
1224         return err;
1225
1226 do_sync:
1227         spin_unlock(&ci->i_ceph_lock);
1228 do_sync_unlocked:
1229         if (lock_snap_rwsem)
1230                 up_read(&mdsc->snap_rwsem);
1231
1232         /* security module set xattr while filling trace */
1233         if (current->journal_info) {
1234                 pr_warn_ratelimited("sync setxattr %p "
1235                                     "during filling trace\n", inode);
1236                 err = -EBUSY;
1237         } else {
1238                 err = ceph_sync_setxattr(inode, name, value, size, flags);
1239                 if (err >= 0 && check_realm) {
1240                         /* check if snaprealm was created for quota inode */
1241                         spin_lock(&ci->i_ceph_lock);
1242                         if ((ci->i_max_files || ci->i_max_bytes) &&
1243                             !(ci->i_snap_realm &&
1244                               ci->i_snap_realm->ino == ci->i_vino.ino))
1245                                 err = -EOPNOTSUPP;
1246                         spin_unlock(&ci->i_ceph_lock);
1247                 }
1248         }
1249 out:
1250         ceph_free_cap_flush(prealloc_cf);
1251         kfree(newname);
1252         kfree(newval);
1253         kfree(xattr);
1254         return err;
1255 }
1256
1257 static int ceph_get_xattr_handler(const struct xattr_handler *handler,
1258                                   struct dentry *dentry, struct inode *inode,
1259                                   const char *name, void *value, size_t size)
1260 {
1261         if (!ceph_is_valid_xattr(name))
1262                 return -EOPNOTSUPP;
1263         return __ceph_getxattr(inode, name, value, size);
1264 }
1265
1266 static int ceph_set_xattr_handler(const struct xattr_handler *handler,
1267                                   struct user_namespace *mnt_userns,
1268                                   struct dentry *unused, struct inode *inode,
1269                                   const char *name, const void *value,
1270                                   size_t size, int flags)
1271 {
1272         if (!ceph_is_valid_xattr(name))
1273                 return -EOPNOTSUPP;
1274         return __ceph_setxattr(inode, name, value, size, flags);
1275 }
1276
1277 static const struct xattr_handler ceph_other_xattr_handler = {
1278         .prefix = "",  /* match any name => handlers called with full name */
1279         .get = ceph_get_xattr_handler,
1280         .set = ceph_set_xattr_handler,
1281 };
1282
1283 #ifdef CONFIG_SECURITY
1284 bool ceph_security_xattr_wanted(struct inode *in)
1285 {
1286         return in->i_security != NULL;
1287 }
1288
1289 bool ceph_security_xattr_deadlock(struct inode *in)
1290 {
1291         struct ceph_inode_info *ci;
1292         bool ret;
1293         if (!in->i_security)
1294                 return false;
1295         ci = ceph_inode(in);
1296         spin_lock(&ci->i_ceph_lock);
1297         ret = !(ci->i_ceph_flags & CEPH_I_SEC_INITED) &&
1298               !(ci->i_xattrs.version > 0 &&
1299                 __ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0));
1300         spin_unlock(&ci->i_ceph_lock);
1301         return ret;
1302 }
1303
1304 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1305 int ceph_security_init_secctx(struct dentry *dentry, umode_t mode,
1306                            struct ceph_acl_sec_ctx *as_ctx)
1307 {
1308         struct ceph_pagelist *pagelist = as_ctx->pagelist;
1309         const char *name;
1310         size_t name_len;
1311         int err;
1312
1313         err = security_dentry_init_security(dentry, mode, &dentry->d_name,
1314                                             &as_ctx->sec_ctx,
1315                                             &as_ctx->sec_ctxlen);
1316         if (err < 0) {
1317                 WARN_ON_ONCE(err != -EOPNOTSUPP);
1318                 err = 0; /* do nothing */
1319                 goto out;
1320         }
1321
1322         err = -ENOMEM;
1323         if (!pagelist) {
1324                 pagelist = ceph_pagelist_alloc(GFP_KERNEL);
1325                 if (!pagelist)
1326                         goto out;
1327                 err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
1328                 if (err)
1329                         goto out;
1330                 ceph_pagelist_encode_32(pagelist, 1);
1331         }
1332
1333         /*
1334          * FIXME: Make security_dentry_init_security() generic. Currently
1335          * It only supports single security module and only selinux has
1336          * dentry_init_security hook.
1337          */
1338         name = XATTR_NAME_SELINUX;
1339         name_len = strlen(name);
1340         err = ceph_pagelist_reserve(pagelist,
1341                                     4 * 2 + name_len + as_ctx->sec_ctxlen);
1342         if (err)
1343                 goto out;
1344
1345         if (as_ctx->pagelist) {
1346                 /* update count of KV pairs */
1347                 BUG_ON(pagelist->length <= sizeof(__le32));
1348                 if (list_is_singular(&pagelist->head)) {
1349                         le32_add_cpu((__le32*)pagelist->mapped_tail, 1);
1350                 } else {
1351                         struct page *page = list_first_entry(&pagelist->head,
1352                                                              struct page, lru);
1353                         void *addr = kmap_atomic(page);
1354                         le32_add_cpu((__le32*)addr, 1);
1355                         kunmap_atomic(addr);
1356                 }
1357         } else {
1358                 as_ctx->pagelist = pagelist;
1359         }
1360
1361         ceph_pagelist_encode_32(pagelist, name_len);
1362         ceph_pagelist_append(pagelist, name, name_len);
1363
1364         ceph_pagelist_encode_32(pagelist, as_ctx->sec_ctxlen);
1365         ceph_pagelist_append(pagelist, as_ctx->sec_ctx, as_ctx->sec_ctxlen);
1366
1367         err = 0;
1368 out:
1369         if (pagelist && !as_ctx->pagelist)
1370                 ceph_pagelist_release(pagelist);
1371         return err;
1372 }
1373 #endif /* CONFIG_CEPH_FS_SECURITY_LABEL */
1374 #endif /* CONFIG_SECURITY */
1375
1376 void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx)
1377 {
1378 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1379         struct lsmcontext scaff; /* scaffolding */
1380 #endif
1381 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1382         posix_acl_release(as_ctx->acl);
1383         posix_acl_release(as_ctx->default_acl);
1384 #endif
1385 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1386         lsmcontext_init(&scaff, as_ctx->sec_ctx, as_ctx->sec_ctxlen, 0);
1387         security_release_secctx(&scaff);
1388 #endif
1389         if (as_ctx->pagelist)
1390                 ceph_pagelist_release(as_ctx->pagelist);
1391 }
1392
1393 /*
1394  * List of handlers for synthetic system.* attributes. Other
1395  * attributes are handled directly.
1396  */
1397 const struct xattr_handler *ceph_xattr_handlers[] = {
1398 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1399         &posix_acl_access_xattr_handler,
1400         &posix_acl_default_xattr_handler,
1401 #endif
1402         &ceph_other_xattr_handler,
1403         NULL,
1404 };