linux/fs/ceph/xattr.c
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   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
  18static int __remove_xattr(struct ceph_inode_info *ci,
  19                          struct ceph_inode_xattr *xattr);
  20
  21static 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 */
  33struct 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
  49static 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
  57static 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 */
 120static __printf(3, 4)
 121int 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
 142static 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
 148static 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
 154static 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
 160static 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
 182static 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
 199static 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
 205static 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
 211static 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
 217static 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
 224static 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
 230static 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
 236static 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
 242static 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
 248static 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 */
 256static bool ceph_vxattrcb_dir_pin_exists(struct ceph_inode_info *ci)
 257{
 258        return ci->i_dir_pin != -ENODATA;
 259}
 260
 261static 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 */
 268static 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
 281static 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
 288static 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
 294static 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 */
 301static 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
 306static 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
 313static 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
 321static 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
 330static 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#define CEPH_XATTR_NAME(_type, _name)   XATTR_CEPH_PREFIX #_type "." #_name
 344#define CEPH_XATTR_NAME2(_type, _name, _name2)  \
 345        XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
 346
 347#define XATTR_NAME_CEPH(_type, _name, _flags)                           \
 348        {                                                               \
 349                .name = CEPH_XATTR_NAME(_type, _name),                  \
 350                .name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
 351                .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
 352                .exists_cb = NULL,                                      \
 353                .flags = (VXATTR_FLAG_READONLY | _flags),               \
 354        }
 355#define XATTR_RSTAT_FIELD(_type, _name)                 \
 356        XATTR_NAME_CEPH(_type, _name, VXATTR_FLAG_RSTAT)
 357#define XATTR_LAYOUT_FIELD(_type, _name, _field)                        \
 358        {                                                               \
 359                .name = CEPH_XATTR_NAME2(_type, _name, _field), \
 360                .name_size = sizeof (CEPH_XATTR_NAME2(_type, _name, _field)), \
 361                .getxattr_cb = ceph_vxattrcb_ ## _name ## _ ## _field, \
 362                .exists_cb = ceph_vxattrcb_layout_exists,       \
 363                .flags = VXATTR_FLAG_HIDDEN,                    \
 364        }
 365#define XATTR_QUOTA_FIELD(_type, _name)                                 \
 366        {                                                               \
 367                .name = CEPH_XATTR_NAME(_type, _name),                  \
 368                .name_size = sizeof(CEPH_XATTR_NAME(_type, _name)),     \
 369                .getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name,   \
 370                .exists_cb = ceph_vxattrcb_quota_exists,                \
 371                .flags = VXATTR_FLAG_HIDDEN,                            \
 372        }
 373
 374static struct ceph_vxattr ceph_dir_vxattrs[] = {
 375        {
 376                .name = "ceph.dir.layout",
 377                .name_size = sizeof("ceph.dir.layout"),
 378                .getxattr_cb = ceph_vxattrcb_layout,
 379                .exists_cb = ceph_vxattrcb_layout_exists,
 380                .flags = VXATTR_FLAG_HIDDEN,
 381        },
 382        XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
 383        XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
 384        XATTR_LAYOUT_FIELD(dir, layout, object_size),
 385        XATTR_LAYOUT_FIELD(dir, layout, pool),
 386        XATTR_LAYOUT_FIELD(dir, layout, pool_namespace),
 387        XATTR_NAME_CEPH(dir, entries, VXATTR_FLAG_DIRSTAT),
 388        XATTR_NAME_CEPH(dir, files, VXATTR_FLAG_DIRSTAT),
 389        XATTR_NAME_CEPH(dir, subdirs, VXATTR_FLAG_DIRSTAT),
 390        XATTR_RSTAT_FIELD(dir, rentries),
 391        XATTR_RSTAT_FIELD(dir, rfiles),
 392        XATTR_RSTAT_FIELD(dir, rsubdirs),
 393        XATTR_RSTAT_FIELD(dir, rsnaps),
 394        XATTR_RSTAT_FIELD(dir, rbytes),
 395        XATTR_RSTAT_FIELD(dir, rctime),
 396        {
 397                .name = "ceph.dir.pin",
 398                .name_size = sizeof("ceph.dir.pin"),
 399                .getxattr_cb = ceph_vxattrcb_dir_pin,
 400                .exists_cb = ceph_vxattrcb_dir_pin_exists,
 401                .flags = VXATTR_FLAG_HIDDEN,
 402        },
 403        {
 404                .name = "ceph.quota",
 405                .name_size = sizeof("ceph.quota"),
 406                .getxattr_cb = ceph_vxattrcb_quota,
 407                .exists_cb = ceph_vxattrcb_quota_exists,
 408                .flags = VXATTR_FLAG_HIDDEN,
 409        },
 410        XATTR_QUOTA_FIELD(quota, max_bytes),
 411        XATTR_QUOTA_FIELD(quota, max_files),
 412        {
 413                .name = "ceph.snap.btime",
 414                .name_size = sizeof("ceph.snap.btime"),
 415                .getxattr_cb = ceph_vxattrcb_snap_btime,
 416                .exists_cb = ceph_vxattrcb_snap_btime_exists,
 417                .flags = VXATTR_FLAG_READONLY,
 418        },
 419        {
 420                .name = "ceph.caps",
 421                .name_size = sizeof("ceph.caps"),
 422                .getxattr_cb = ceph_vxattrcb_caps,
 423                .exists_cb = NULL,
 424                .flags = VXATTR_FLAG_HIDDEN,
 425        },
 426        { .name = NULL, 0 }     /* Required table terminator */
 427};
 428
 429/* files */
 430
 431static struct ceph_vxattr ceph_file_vxattrs[] = {
 432        {
 433                .name = "ceph.file.layout",
 434                .name_size = sizeof("ceph.file.layout"),
 435                .getxattr_cb = ceph_vxattrcb_layout,
 436                .exists_cb = ceph_vxattrcb_layout_exists,
 437                .flags = VXATTR_FLAG_HIDDEN,
 438        },
 439        XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
 440        XATTR_LAYOUT_FIELD(file, layout, stripe_count),
 441        XATTR_LAYOUT_FIELD(file, layout, object_size),
 442        XATTR_LAYOUT_FIELD(file, layout, pool),
 443        XATTR_LAYOUT_FIELD(file, layout, pool_namespace),
 444        {
 445                .name = "ceph.snap.btime",
 446                .name_size = sizeof("ceph.snap.btime"),
 447                .getxattr_cb = ceph_vxattrcb_snap_btime,
 448                .exists_cb = ceph_vxattrcb_snap_btime_exists,
 449                .flags = VXATTR_FLAG_READONLY,
 450        },
 451        {
 452                .name = "ceph.caps",
 453                .name_size = sizeof("ceph.caps"),
 454                .getxattr_cb = ceph_vxattrcb_caps,
 455                .exists_cb = NULL,
 456                .flags = VXATTR_FLAG_HIDDEN,
 457        },
 458        { .name = NULL, 0 }     /* Required table terminator */
 459};
 460
 461static struct ceph_vxattr ceph_common_vxattrs[] = {
 462        {
 463                .name = "ceph.cluster_fsid",
 464                .name_size = sizeof("ceph.cluster_fsid"),
 465                .getxattr_cb = ceph_vxattrcb_cluster_fsid,
 466                .exists_cb = NULL,
 467                .flags = VXATTR_FLAG_READONLY,
 468        },
 469        {
 470                .name = "ceph.client_id",
 471                .name_size = sizeof("ceph.client_id"),
 472                .getxattr_cb = ceph_vxattrcb_client_id,
 473                .exists_cb = NULL,
 474                .flags = VXATTR_FLAG_READONLY,
 475        },
 476        { .name = NULL, 0 }     /* Required table terminator */
 477};
 478
 479static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
 480{
 481        if (S_ISDIR(inode->i_mode))
 482                return ceph_dir_vxattrs;
 483        else if (S_ISREG(inode->i_mode))
 484                return ceph_file_vxattrs;
 485        return NULL;
 486}
 487
 488static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
 489                                                const char *name)
 490{
 491        struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
 492
 493        if (vxattr) {
 494                while (vxattr->name) {
 495                        if (!strcmp(vxattr->name, name))
 496                                return vxattr;
 497                        vxattr++;
 498                }
 499        }
 500
 501        vxattr = ceph_common_vxattrs;
 502        while (vxattr->name) {
 503                if (!strcmp(vxattr->name, name))
 504                        return vxattr;
 505                vxattr++;
 506        }
 507
 508        return NULL;
 509}
 510
 511static int __set_xattr(struct ceph_inode_info *ci,
 512                           const char *name, int name_len,
 513                           const char *val, int val_len,
 514                           int flags, int update_xattr,
 515                           struct ceph_inode_xattr **newxattr)
 516{
 517        struct rb_node **p;
 518        struct rb_node *parent = NULL;
 519        struct ceph_inode_xattr *xattr = NULL;
 520        int c;
 521        int new = 0;
 522
 523        p = &ci->i_xattrs.index.rb_node;
 524        while (*p) {
 525                parent = *p;
 526                xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 527                c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
 528                if (c < 0)
 529                        p = &(*p)->rb_left;
 530                else if (c > 0)
 531                        p = &(*p)->rb_right;
 532                else {
 533                        if (name_len == xattr->name_len)
 534                                break;
 535                        else if (name_len < xattr->name_len)
 536                                p = &(*p)->rb_left;
 537                        else
 538                                p = &(*p)->rb_right;
 539                }
 540                xattr = NULL;
 541        }
 542
 543        if (update_xattr) {
 544                int err = 0;
 545
 546                if (xattr && (flags & XATTR_CREATE))
 547                        err = -EEXIST;
 548                else if (!xattr && (flags & XATTR_REPLACE))
 549                        err = -ENODATA;
 550                if (err) {
 551                        kfree(name);
 552                        kfree(val);
 553                        kfree(*newxattr);
 554                        return err;
 555                }
 556                if (update_xattr < 0) {
 557                        if (xattr)
 558                                __remove_xattr(ci, xattr);
 559                        kfree(name);
 560                        kfree(*newxattr);
 561                        return 0;
 562                }
 563        }
 564
 565        if (!xattr) {
 566                new = 1;
 567                xattr = *newxattr;
 568                xattr->name = name;
 569                xattr->name_len = name_len;
 570                xattr->should_free_name = update_xattr;
 571
 572                ci->i_xattrs.count++;
 573                dout("__set_xattr count=%d\n", ci->i_xattrs.count);
 574        } else {
 575                kfree(*newxattr);
 576                *newxattr = NULL;
 577                if (xattr->should_free_val)
 578                        kfree(xattr->val);
 579
 580                if (update_xattr) {
 581                        kfree(name);
 582                        name = xattr->name;
 583                }
 584                ci->i_xattrs.names_size -= xattr->name_len;
 585                ci->i_xattrs.vals_size -= xattr->val_len;
 586        }
 587        ci->i_xattrs.names_size += name_len;
 588        ci->i_xattrs.vals_size += val_len;
 589        if (val)
 590                xattr->val = val;
 591        else
 592                xattr->val = "";
 593
 594        xattr->val_len = val_len;
 595        xattr->dirty = update_xattr;
 596        xattr->should_free_val = (val && update_xattr);
 597
 598        if (new) {
 599                rb_link_node(&xattr->node, parent, p);
 600                rb_insert_color(&xattr->node, &ci->i_xattrs.index);
 601                dout("__set_xattr_val p=%p\n", p);
 602        }
 603
 604        dout("__set_xattr_val added %llx.%llx xattr %p %.*s=%.*s\n",
 605             ceph_vinop(&ci->vfs_inode), xattr, name_len, name, val_len, val);
 606
 607        return 0;
 608}
 609
 610static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
 611                           const char *name)
 612{
 613        struct rb_node **p;
 614        struct rb_node *parent = NULL;
 615        struct ceph_inode_xattr *xattr = NULL;
 616        int name_len = strlen(name);
 617        int c;
 618
 619        p = &ci->i_xattrs.index.rb_node;
 620        while (*p) {
 621                parent = *p;
 622                xattr = rb_entry(parent, struct ceph_inode_xattr, node);
 623                c = strncmp(name, xattr->name, xattr->name_len);
 624                if (c == 0 && name_len > xattr->name_len)
 625                        c = 1;
 626                if (c < 0)
 627                        p = &(*p)->rb_left;
 628                else if (c > 0)
 629                        p = &(*p)->rb_right;
 630                else {
 631                        dout("__get_xattr %s: found %.*s\n", name,
 632                             xattr->val_len, xattr->val);
 633                        return xattr;
 634                }
 635        }
 636
 637        dout("__get_xattr %s: not found\n", name);
 638
 639        return NULL;
 640}
 641
 642static void __free_xattr(struct ceph_inode_xattr *xattr)
 643{
 644        BUG_ON(!xattr);
 645
 646        if (xattr->should_free_name)
 647                kfree(xattr->name);
 648        if (xattr->should_free_val)
 649                kfree(xattr->val);
 650
 651        kfree(xattr);
 652}
 653
 654static int __remove_xattr(struct ceph_inode_info *ci,
 655                          struct ceph_inode_xattr *xattr)
 656{
 657        if (!xattr)
 658                return -ENODATA;
 659
 660        rb_erase(&xattr->node, &ci->i_xattrs.index);
 661
 662        if (xattr->should_free_name)
 663                kfree(xattr->name);
 664        if (xattr->should_free_val)
 665                kfree(xattr->val);
 666
 667        ci->i_xattrs.names_size -= xattr->name_len;
 668        ci->i_xattrs.vals_size -= xattr->val_len;
 669        ci->i_xattrs.count--;
 670        kfree(xattr);
 671
 672        return 0;
 673}
 674
 675static char *__copy_xattr_names(struct ceph_inode_info *ci,
 676                                char *dest)
 677{
 678        struct rb_node *p;
 679        struct ceph_inode_xattr *xattr = NULL;
 680
 681        p = rb_first(&ci->i_xattrs.index);
 682        dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
 683
 684        while (p) {
 685                xattr = rb_entry(p, struct ceph_inode_xattr, node);
 686                memcpy(dest, xattr->name, xattr->name_len);
 687                dest[xattr->name_len] = '\0';
 688
 689                dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
 690                     xattr->name_len, ci->i_xattrs.names_size);
 691
 692                dest += xattr->name_len + 1;
 693                p = rb_next(p);
 694        }
 695
 696        return dest;
 697}
 698
 699void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
 700{
 701        struct rb_node *p, *tmp;
 702        struct ceph_inode_xattr *xattr = NULL;
 703
 704        p = rb_first(&ci->i_xattrs.index);
 705
 706        dout("__ceph_destroy_xattrs p=%p\n", p);
 707
 708        while (p) {
 709                xattr = rb_entry(p, struct ceph_inode_xattr, node);
 710                tmp = p;
 711                p = rb_next(tmp);
 712                dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
 713                     xattr->name_len, xattr->name);
 714                rb_erase(tmp, &ci->i_xattrs.index);
 715
 716                __free_xattr(xattr);
 717        }
 718
 719        ci->i_xattrs.names_size = 0;
 720        ci->i_xattrs.vals_size = 0;
 721        ci->i_xattrs.index_version = 0;
 722        ci->i_xattrs.count = 0;
 723        ci->i_xattrs.index = RB_ROOT;
 724}
 725
 726static int __build_xattrs(struct inode *inode)
 727        __releases(ci->i_ceph_lock)
 728        __acquires(ci->i_ceph_lock)
 729{
 730        u32 namelen;
 731        u32 numattr = 0;
 732        void *p, *end;
 733        u32 len;
 734        const char *name, *val;
 735        struct ceph_inode_info *ci = ceph_inode(inode);
 736        u64 xattr_version;
 737        struct ceph_inode_xattr **xattrs = NULL;
 738        int err = 0;
 739        int i;
 740
 741        dout("__build_xattrs() len=%d\n",
 742             ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
 743
 744        if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
 745                return 0; /* already built */
 746
 747        __ceph_destroy_xattrs(ci);
 748
 749start:
 750        /* updated internal xattr rb tree */
 751        if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
 752                p = ci->i_xattrs.blob->vec.iov_base;
 753                end = p + ci->i_xattrs.blob->vec.iov_len;
 754                ceph_decode_32_safe(&p, end, numattr, bad);
 755                xattr_version = ci->i_xattrs.version;
 756                spin_unlock(&ci->i_ceph_lock);
 757
 758                xattrs = kcalloc(numattr, sizeof(struct ceph_inode_xattr *),
 759                                 GFP_NOFS);
 760                err = -ENOMEM;
 761                if (!xattrs)
 762                        goto bad_lock;
 763
 764                for (i = 0; i < numattr; i++) {
 765                        xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
 766                                            GFP_NOFS);
 767                        if (!xattrs[i])
 768                                goto bad_lock;
 769                }
 770
 771                spin_lock(&ci->i_ceph_lock);
 772                if (ci->i_xattrs.version != xattr_version) {
 773                        /* lost a race, retry */
 774                        for (i = 0; i < numattr; i++)
 775                                kfree(xattrs[i]);
 776                        kfree(xattrs);
 777                        xattrs = NULL;
 778                        goto start;
 779                }
 780                err = -EIO;
 781                while (numattr--) {
 782                        ceph_decode_32_safe(&p, end, len, bad);
 783                        namelen = len;
 784                        name = p;
 785                        p += len;
 786                        ceph_decode_32_safe(&p, end, len, bad);
 787                        val = p;
 788                        p += len;
 789
 790                        err = __set_xattr(ci, name, namelen, val, len,
 791                                          0, 0, &xattrs[numattr]);
 792
 793                        if (err < 0)
 794                                goto bad;
 795                }
 796                kfree(xattrs);
 797        }
 798        ci->i_xattrs.index_version = ci->i_xattrs.version;
 799        ci->i_xattrs.dirty = false;
 800
 801        return err;
 802bad_lock:
 803        spin_lock(&ci->i_ceph_lock);
 804bad:
 805        if (xattrs) {
 806                for (i = 0; i < numattr; i++)
 807                        kfree(xattrs[i]);
 808                kfree(xattrs);
 809        }
 810        ci->i_xattrs.names_size = 0;
 811        return err;
 812}
 813
 814static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
 815                                    int val_size)
 816{
 817        /*
 818         * 4 bytes for the length, and additional 4 bytes per each xattr name,
 819         * 4 bytes per each value
 820         */
 821        int size = 4 + ci->i_xattrs.count*(4 + 4) +
 822                             ci->i_xattrs.names_size +
 823                             ci->i_xattrs.vals_size;
 824        dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
 825             ci->i_xattrs.count, ci->i_xattrs.names_size,
 826             ci->i_xattrs.vals_size);
 827
 828        if (name_size)
 829                size += 4 + 4 + name_size + val_size;
 830
 831        return size;
 832}
 833
 834/*
 835 * If there are dirty xattrs, reencode xattrs into the prealloc_blob
 836 * and swap into place.  It returns the old i_xattrs.blob (or NULL) so
 837 * that it can be freed by the caller as the i_ceph_lock is likely to be
 838 * held.
 839 */
 840struct ceph_buffer *__ceph_build_xattrs_blob(struct ceph_inode_info *ci)
 841{
 842        struct rb_node *p;
 843        struct ceph_inode_xattr *xattr = NULL;
 844        struct ceph_buffer *old_blob = NULL;
 845        void *dest;
 846
 847        dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
 848        if (ci->i_xattrs.dirty) {
 849                int need = __get_required_blob_size(ci, 0, 0);
 850
 851                BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
 852
 853                p = rb_first(&ci->i_xattrs.index);
 854                dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
 855
 856                ceph_encode_32(&dest, ci->i_xattrs.count);
 857                while (p) {
 858                        xattr = rb_entry(p, struct ceph_inode_xattr, node);
 859
 860                        ceph_encode_32(&dest, xattr->name_len);
 861                        memcpy(dest, xattr->name, xattr->name_len);
 862                        dest += xattr->name_len;
 863                        ceph_encode_32(&dest, xattr->val_len);
 864                        memcpy(dest, xattr->val, xattr->val_len);
 865                        dest += xattr->val_len;
 866
 867                        p = rb_next(p);
 868                }
 869
 870                /* adjust buffer len; it may be larger than we need */
 871                ci->i_xattrs.prealloc_blob->vec.iov_len =
 872                        dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
 873
 874                if (ci->i_xattrs.blob)
 875                        old_blob = ci->i_xattrs.blob;
 876                ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
 877                ci->i_xattrs.prealloc_blob = NULL;
 878                ci->i_xattrs.dirty = false;
 879                ci->i_xattrs.version++;
 880        }
 881
 882        return old_blob;
 883}
 884
 885static inline int __get_request_mask(struct inode *in) {
 886        struct ceph_mds_request *req = current->journal_info;
 887        int mask = 0;
 888        if (req && req->r_target_inode == in) {
 889                if (req->r_op == CEPH_MDS_OP_LOOKUP ||
 890                    req->r_op == CEPH_MDS_OP_LOOKUPINO ||
 891                    req->r_op == CEPH_MDS_OP_LOOKUPPARENT ||
 892                    req->r_op == CEPH_MDS_OP_GETATTR) {
 893                        mask = le32_to_cpu(req->r_args.getattr.mask);
 894                } else if (req->r_op == CEPH_MDS_OP_OPEN ||
 895                           req->r_op == CEPH_MDS_OP_CREATE) {
 896                        mask = le32_to_cpu(req->r_args.open.mask);
 897                }
 898        }
 899        return mask;
 900}
 901
 902ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 903                      size_t size)
 904{
 905        struct ceph_inode_info *ci = ceph_inode(inode);
 906        struct ceph_inode_xattr *xattr;
 907        struct ceph_vxattr *vxattr = NULL;
 908        int req_mask;
 909        ssize_t err;
 910
 911        /* let's see if a virtual xattr was requested */
 912        vxattr = ceph_match_vxattr(inode, name);
 913        if (vxattr) {
 914                int mask = 0;
 915                if (vxattr->flags & VXATTR_FLAG_RSTAT)
 916                        mask |= CEPH_STAT_RSTAT;
 917                if (vxattr->flags & VXATTR_FLAG_DIRSTAT)
 918                        mask |= CEPH_CAP_FILE_SHARED;
 919                err = ceph_do_getattr(inode, mask, true);
 920                if (err)
 921                        return err;
 922                err = -ENODATA;
 923                if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
 924                        err = vxattr->getxattr_cb(ci, value, size);
 925                        if (size && size < err)
 926                                err = -ERANGE;
 927                }
 928                return err;
 929        }
 930
 931        req_mask = __get_request_mask(inode);
 932
 933        spin_lock(&ci->i_ceph_lock);
 934        dout("getxattr %p name '%s' ver=%lld index_ver=%lld\n", inode, name,
 935             ci->i_xattrs.version, ci->i_xattrs.index_version);
 936
 937        if (ci->i_xattrs.version == 0 ||
 938            !((req_mask & CEPH_CAP_XATTR_SHARED) ||
 939              __ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1))) {
 940                spin_unlock(&ci->i_ceph_lock);
 941
 942                /* security module gets xattr while filling trace */
 943                if (current->journal_info) {
 944                        pr_warn_ratelimited("sync getxattr %p "
 945                                            "during filling trace\n", inode);
 946                        return -EBUSY;
 947                }
 948
 949                /* get xattrs from mds (if we don't already have them) */
 950                err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
 951                if (err)
 952                        return err;
 953                spin_lock(&ci->i_ceph_lock);
 954        }
 955
 956        err = __build_xattrs(inode);
 957        if (err < 0)
 958                goto out;
 959
 960        err = -ENODATA;  /* == ENOATTR */
 961        xattr = __get_xattr(ci, name);
 962        if (!xattr)
 963                goto out;
 964
 965        err = -ERANGE;
 966        if (size && size < xattr->val_len)
 967                goto out;
 968
 969        err = xattr->val_len;
 970        if (size == 0)
 971                goto out;
 972
 973        memcpy(value, xattr->val, xattr->val_len);
 974
 975        if (current->journal_info &&
 976            !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
 977            security_ismaclabel(name + XATTR_SECURITY_PREFIX_LEN))
 978                ci->i_ceph_flags |= CEPH_I_SEC_INITED;
 979out:
 980        spin_unlock(&ci->i_ceph_lock);
 981        return err;
 982}
 983
 984ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 985{
 986        struct inode *inode = d_inode(dentry);
 987        struct ceph_inode_info *ci = ceph_inode(inode);
 988        bool len_only = (size == 0);
 989        u32 namelen;
 990        int err;
 991
 992        spin_lock(&ci->i_ceph_lock);
 993        dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
 994             ci->i_xattrs.version, ci->i_xattrs.index_version);
 995
 996        if (ci->i_xattrs.version == 0 ||
 997            !__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1)) {
 998                spin_unlock(&ci->i_ceph_lock);
 999                err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
1000                if (err)
1001                        return err;
1002                spin_lock(&ci->i_ceph_lock);
1003        }
1004
1005        err = __build_xattrs(inode);
1006        if (err < 0)
1007                goto out;
1008
1009        /* add 1 byte for each xattr due to the null termination */
1010        namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
1011        if (!len_only) {
1012                if (namelen > size) {
1013                        err = -ERANGE;
1014                        goto out;
1015                }
1016                names = __copy_xattr_names(ci, names);
1017                size -= namelen;
1018        }
1019        err = namelen;
1020out:
1021        spin_unlock(&ci->i_ceph_lock);
1022        return err;
1023}
1024
1025static int ceph_sync_setxattr(struct inode *inode, const char *name,
1026                              const char *value, size_t size, int flags)
1027{
1028        struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
1029        struct ceph_inode_info *ci = ceph_inode(inode);
1030        struct ceph_mds_request *req;
1031        struct ceph_mds_client *mdsc = fsc->mdsc;
1032        struct ceph_osd_client *osdc = &fsc->client->osdc;
1033        struct ceph_pagelist *pagelist = NULL;
1034        int op = CEPH_MDS_OP_SETXATTR;
1035        int err;
1036
1037        if (size > 0) {
1038                /* copy value into pagelist */
1039                pagelist = ceph_pagelist_alloc(GFP_NOFS);
1040                if (!pagelist)
1041                        return -ENOMEM;
1042
1043                err = ceph_pagelist_append(pagelist, value, size);
1044                if (err)
1045                        goto out;
1046        } else if (!value) {
1047                if (flags & CEPH_XATTR_REPLACE)
1048                        op = CEPH_MDS_OP_RMXATTR;
1049                else
1050                        flags |= CEPH_XATTR_REMOVE;
1051        }
1052
1053        dout("setxattr value=%.*s\n", (int)size, value);
1054
1055        /* do request */
1056        req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1057        if (IS_ERR(req)) {
1058                err = PTR_ERR(req);
1059                goto out;
1060        }
1061
1062        req->r_path2 = kstrdup(name, GFP_NOFS);
1063        if (!req->r_path2) {
1064                ceph_mdsc_put_request(req);
1065                err = -ENOMEM;
1066                goto out;
1067        }
1068
1069        if (op == CEPH_MDS_OP_SETXATTR) {
1070                req->r_args.setxattr.flags = cpu_to_le32(flags);
1071                req->r_args.setxattr.osdmap_epoch =
1072                        cpu_to_le32(osdc->osdmap->epoch);
1073                req->r_pagelist = pagelist;
1074                pagelist = NULL;
1075        }
1076
1077        req->r_inode = inode;
1078        ihold(inode);
1079        req->r_num_caps = 1;
1080        req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
1081
1082        dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
1083        err = ceph_mdsc_do_request(mdsc, NULL, req);
1084        ceph_mdsc_put_request(req);
1085        dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
1086
1087out:
1088        if (pagelist)
1089                ceph_pagelist_release(pagelist);
1090        return err;
1091}
1092
1093int __ceph_setxattr(struct inode *inode, const char *name,
1094                        const void *value, size_t size, int flags)
1095{
1096        struct ceph_vxattr *vxattr;
1097        struct ceph_inode_info *ci = ceph_inode(inode);
1098        struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1099        struct ceph_cap_flush *prealloc_cf = NULL;
1100        struct ceph_buffer *old_blob = NULL;
1101        int issued;
1102        int err;
1103        int dirty = 0;
1104        int name_len = strlen(name);
1105        int val_len = size;
1106        char *newname = NULL;
1107        char *newval = NULL;
1108        struct ceph_inode_xattr *xattr = NULL;
1109        int required_blob_size;
1110        bool check_realm = false;
1111        bool lock_snap_rwsem = false;
1112
1113        if (ceph_snap(inode) != CEPH_NOSNAP)
1114                return -EROFS;
1115
1116        vxattr = ceph_match_vxattr(inode, name);
1117        if (vxattr) {
1118                if (vxattr->flags & VXATTR_FLAG_READONLY)
1119                        return -EOPNOTSUPP;
1120                if (value && !strncmp(vxattr->name, "ceph.quota", 10))
1121                        check_realm = true;
1122        }
1123
1124        /* pass any unhandled ceph.* xattrs through to the MDS */
1125        if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
1126                goto do_sync_unlocked;
1127
1128        /* preallocate memory for xattr name, value, index node */
1129        err = -ENOMEM;
1130        newname = kmemdup(name, name_len + 1, GFP_NOFS);
1131        if (!newname)
1132                goto out;
1133
1134        if (val_len) {
1135                newval = kmemdup(value, val_len, GFP_NOFS);
1136                if (!newval)
1137                        goto out;
1138        }
1139
1140        xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
1141        if (!xattr)
1142                goto out;
1143
1144        prealloc_cf = ceph_alloc_cap_flush();
1145        if (!prealloc_cf)
1146                goto out;
1147
1148        spin_lock(&ci->i_ceph_lock);
1149retry:
1150        issued = __ceph_caps_issued(ci, NULL);
1151        if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
1152                goto do_sync;
1153
1154        if (!lock_snap_rwsem && !ci->i_head_snapc) {
1155                lock_snap_rwsem = true;
1156                if (!down_read_trylock(&mdsc->snap_rwsem)) {
1157                        spin_unlock(&ci->i_ceph_lock);
1158                        down_read(&mdsc->snap_rwsem);
1159                        spin_lock(&ci->i_ceph_lock);
1160                        goto retry;
1161                }
1162        }
1163
1164        dout("setxattr %p name '%s' issued %s\n", inode, name,
1165             ceph_cap_string(issued));
1166        __build_xattrs(inode);
1167
1168        required_blob_size = __get_required_blob_size(ci, name_len, val_len);
1169
1170        if (!ci->i_xattrs.prealloc_blob ||
1171            required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
1172                struct ceph_buffer *blob;
1173
1174                spin_unlock(&ci->i_ceph_lock);
1175                ceph_buffer_put(old_blob); /* Shouldn't be required */
1176                dout(" pre-allocating new blob size=%d\n", required_blob_size);
1177                blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
1178                if (!blob)
1179                        goto do_sync_unlocked;
1180                spin_lock(&ci->i_ceph_lock);
1181                /* prealloc_blob can't be released while holding i_ceph_lock */
1182                if (ci->i_xattrs.prealloc_blob)
1183                        old_blob = ci->i_xattrs.prealloc_blob;
1184                ci->i_xattrs.prealloc_blob = blob;
1185                goto retry;
1186        }
1187
1188        err = __set_xattr(ci, newname, name_len, newval, val_len,
1189                          flags, value ? 1 : -1, &xattr);
1190
1191        if (!err) {
1192                dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1193                                               &prealloc_cf);
1194                ci->i_xattrs.dirty = true;
1195                inode->i_ctime = current_time(inode);
1196        }
1197
1198        spin_unlock(&ci->i_ceph_lock);
1199        ceph_buffer_put(old_blob);
1200        if (lock_snap_rwsem)
1201                up_read(&mdsc->snap_rwsem);
1202        if (dirty)
1203                __mark_inode_dirty(inode, dirty);
1204        ceph_free_cap_flush(prealloc_cf);
1205        return err;
1206
1207do_sync:
1208        spin_unlock(&ci->i_ceph_lock);
1209do_sync_unlocked:
1210        if (lock_snap_rwsem)
1211                up_read(&mdsc->snap_rwsem);
1212
1213        /* security module set xattr while filling trace */
1214        if (current->journal_info) {
1215                pr_warn_ratelimited("sync setxattr %p "
1216                                    "during filling trace\n", inode);
1217                err = -EBUSY;
1218        } else {
1219                err = ceph_sync_setxattr(inode, name, value, size, flags);
1220                if (err >= 0 && check_realm) {
1221                        /* check if snaprealm was created for quota inode */
1222                        spin_lock(&ci->i_ceph_lock);
1223                        if ((ci->i_max_files || ci->i_max_bytes) &&
1224                            !(ci->i_snap_realm &&
1225                              ci->i_snap_realm->ino == ci->i_vino.ino))
1226                                err = -EOPNOTSUPP;
1227                        spin_unlock(&ci->i_ceph_lock);
1228                }
1229        }
1230out:
1231        ceph_free_cap_flush(prealloc_cf);
1232        kfree(newname);
1233        kfree(newval);
1234        kfree(xattr);
1235        return err;
1236}
1237
1238static int ceph_get_xattr_handler(const struct xattr_handler *handler,
1239                                  struct dentry *dentry, struct inode *inode,
1240                                  const char *name, void *value, size_t size)
1241{
1242        if (!ceph_is_valid_xattr(name))
1243                return -EOPNOTSUPP;
1244        return __ceph_getxattr(inode, name, value, size);
1245}
1246
1247static int ceph_set_xattr_handler(const struct xattr_handler *handler,
1248                                  struct user_namespace *mnt_userns,
1249                                  struct dentry *unused, struct inode *inode,
1250                                  const char *name, const void *value,
1251                                  size_t size, int flags)
1252{
1253        if (!ceph_is_valid_xattr(name))
1254                return -EOPNOTSUPP;
1255        return __ceph_setxattr(inode, name, value, size, flags);
1256}
1257
1258static const struct xattr_handler ceph_other_xattr_handler = {
1259        .prefix = "",  /* match any name => handlers called with full name */
1260        .get = ceph_get_xattr_handler,
1261        .set = ceph_set_xattr_handler,
1262};
1263
1264#ifdef CONFIG_SECURITY
1265bool ceph_security_xattr_wanted(struct inode *in)
1266{
1267        return in->i_security != NULL;
1268}
1269
1270bool ceph_security_xattr_deadlock(struct inode *in)
1271{
1272        struct ceph_inode_info *ci;
1273        bool ret;
1274        if (!in->i_security)
1275                return false;
1276        ci = ceph_inode(in);
1277        spin_lock(&ci->i_ceph_lock);
1278        ret = !(ci->i_ceph_flags & CEPH_I_SEC_INITED) &&
1279              !(ci->i_xattrs.version > 0 &&
1280                __ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0));
1281        spin_unlock(&ci->i_ceph_lock);
1282        return ret;
1283}
1284
1285#ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1286int ceph_security_init_secctx(struct dentry *dentry, umode_t mode,
1287                           struct ceph_acl_sec_ctx *as_ctx)
1288{
1289        struct ceph_pagelist *pagelist = as_ctx->pagelist;
1290        const char *name;
1291        size_t name_len;
1292        int err;
1293
1294        err = security_dentry_init_security(dentry, mode, &dentry->d_name,
1295                                            &as_ctx->sec_ctx,
1296                                            &as_ctx->sec_ctxlen);
1297        if (err < 0) {
1298                WARN_ON_ONCE(err != -EOPNOTSUPP);
1299                err = 0; /* do nothing */
1300                goto out;
1301        }
1302
1303        err = -ENOMEM;
1304        if (!pagelist) {
1305                pagelist = ceph_pagelist_alloc(GFP_KERNEL);
1306                if (!pagelist)
1307                        goto out;
1308                err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
1309                if (err)
1310                        goto out;
1311                ceph_pagelist_encode_32(pagelist, 1);
1312        }
1313
1314        /*
1315         * FIXME: Make security_dentry_init_security() generic. Currently
1316         * It only supports single security module and only selinux has
1317         * dentry_init_security hook.
1318         */
1319        name = XATTR_NAME_SELINUX;
1320        name_len = strlen(name);
1321        err = ceph_pagelist_reserve(pagelist,
1322                                    4 * 2 + name_len + as_ctx->sec_ctxlen);
1323        if (err)
1324                goto out;
1325
1326        if (as_ctx->pagelist) {
1327                /* update count of KV pairs */
1328                BUG_ON(pagelist->length <= sizeof(__le32));
1329                if (list_is_singular(&pagelist->head)) {
1330                        le32_add_cpu((__le32*)pagelist->mapped_tail, 1);
1331                } else {
1332                        struct page *page = list_first_entry(&pagelist->head,
1333                                                             struct page, lru);
1334                        void *addr = kmap_atomic(page);
1335                        le32_add_cpu((__le32*)addr, 1);
1336                        kunmap_atomic(addr);
1337                }
1338        } else {
1339                as_ctx->pagelist = pagelist;
1340        }
1341
1342        ceph_pagelist_encode_32(pagelist, name_len);
1343        ceph_pagelist_append(pagelist, name, name_len);
1344
1345        ceph_pagelist_encode_32(pagelist, as_ctx->sec_ctxlen);
1346        ceph_pagelist_append(pagelist, as_ctx->sec_ctx, as_ctx->sec_ctxlen);
1347
1348        err = 0;
1349out:
1350        if (pagelist && !as_ctx->pagelist)
1351                ceph_pagelist_release(pagelist);
1352        return err;
1353}
1354#endif /* CONFIG_CEPH_FS_SECURITY_LABEL */
1355#endif /* CONFIG_SECURITY */
1356
1357void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx)
1358{
1359#ifdef CONFIG_CEPH_FS_POSIX_ACL
1360        posix_acl_release(as_ctx->acl);
1361        posix_acl_release(as_ctx->default_acl);
1362#endif
1363#ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1364        security_release_secctx(as_ctx->sec_ctx, as_ctx->sec_ctxlen);
1365#endif
1366        if (as_ctx->pagelist)
1367                ceph_pagelist_release(as_ctx->pagelist);
1368}
1369
1370/*
1371 * List of handlers for synthetic system.* attributes. Other
1372 * attributes are handled directly.
1373 */
1374const struct xattr_handler *ceph_xattr_handlers[] = {
1375#ifdef CONFIG_CEPH_FS_POSIX_ACL
1376        &posix_acl_access_xattr_handler,
1377        &posix_acl_default_xattr_handler,
1378#endif
1379        &ceph_other_xattr_handler,
1380        NULL,
1381};
1382