module/zfs/zfs_znode.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
  24  * Copyright (c) 2014 Integros [integros.com]
  25  */
  26
  27 /* Portions Copyright 2007 Jeremy Teo */
  28 /* Portions Copyright 2011 Martin Matuska <mm@FreeBSD.org> */
  29
  30 #include <sys/dmu.h>
  31 #include <sys/dmu_objset.h>
  32 #include <sys/dmu_tx.h>
  33 #include <sys/zfs_refcount.h>
  34 #include <sys/stat.h>
  35 #include <sys/zap.h>
  36 #include <sys/zfs_znode.h>
  37 #include <sys/sa.h>
  38 #include <sys/zfs_sa.h>
  39 #include <sys/zfs_stat.h>
  40
  41 #include "zfs_prop.h"
  42 #include "zfs_comutil.h"
  43
  44 static int
  45 zfs_sa_setup(objset_t *osp, sa_attr_type_t **sa_table)
  46 {
  47         uint64_t sa_obj = 0;
  48         int error;
  49
  50         error = zap_lookup(osp, MASTER_NODE_OBJ, ZFS_SA_ATTRS, 8, 1, &sa_obj);
  51         if (error != 0 && error != ENOENT)
  52                 return (error);
  53
  54         error = sa_setup(osp, sa_obj, zfs_attr_table, ZPL_END, sa_table);
  55         return (error);
  56 }
  57
  58 static int
  59 zfs_grab_sa_handle(objset_t *osp, uint64_t obj, sa_handle_t **hdlp,
  60     dmu_buf_t **db, const void *tag)
  61 {
  62         dmu_object_info_t doi;
  63         int error;
  64
  65         if ((error = sa_buf_hold(osp, obj, tag, db)) != 0)
  66                 return (error);
  67
  68         dmu_object_info_from_db(*db, &doi);
  69         if ((doi.doi_bonus_type != DMU_OT_SA &&
  70             doi.doi_bonus_type != DMU_OT_ZNODE) ||
  71             (doi.doi_bonus_type == DMU_OT_ZNODE &&
  72             doi.doi_bonus_size < sizeof (znode_phys_t))) {
  73                 sa_buf_rele(*db, tag);
  74                 return (SET_ERROR(ENOTSUP));
  75         }
  76
  77         error = sa_handle_get(osp, obj, NULL, SA_HDL_PRIVATE, hdlp);
  78         if (error != 0) {
  79                 sa_buf_rele(*db, tag);
  80                 return (error);
  81         }
  82
  83         return (0);
  84 }
  85
  86 static void
  87 zfs_release_sa_handle(sa_handle_t *hdl, dmu_buf_t *db, const void *tag)
  88 {
  89         sa_handle_destroy(hdl);
  90         sa_buf_rele(db, tag);
  91 }
  92
  93 /*
  94  * Given an object number, return its parent object number and whether
  95  * or not the object is an extended attribute directory.
  96  */
  97 int
  98 zfs_obj_to_pobj(objset_t *osp, sa_handle_t *hdl, sa_attr_type_t *sa_table,
  99     uint64_t *pobjp, int *is_xattrdir)
 100 {
 101         uint64_t parent;
 102         uint64_t pflags;
 103         uint64_t mode;
 104         uint64_t parent_mode;
 105         sa_bulk_attr_t bulk[3];
 106         sa_handle_t *sa_hdl;
 107         dmu_buf_t *sa_db;
 108         int count = 0;
 109         int error;
 110
 111         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_PARENT], NULL,
 112             &parent, sizeof (parent));
 113         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_FLAGS], NULL,
 114             &pflags, sizeof (pflags));
 115         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_MODE], NULL,
 116             &mode, sizeof (mode));
 117
 118         if ((error = sa_bulk_lookup(hdl, bulk, count)) != 0)
 119                 return (error);
 120
 121         /*
 122          * When a link is removed its parent pointer is not changed and will
 123          * be invalid.  There are two cases where a link is removed but the
 124          * file stays around, when it goes to the delete queue and when there
 125          * are additional links.
 126          */
 127         error = zfs_grab_sa_handle(osp, parent, &sa_hdl, &sa_db, FTAG);
 128         if (error != 0)
 129                 return (error);
 130
 131         error = sa_lookup(sa_hdl, ZPL_MODE, &parent_mode, sizeof (parent_mode));
 132         zfs_release_sa_handle(sa_hdl, sa_db, FTAG);
 133         if (error != 0)
 134                 return (error);
 135
 136         *is_xattrdir = ((pflags & ZFS_XATTR) != 0) && S_ISDIR(mode);
 137
 138         /*
 139          * Extended attributes can be applied to files, directories, etc.
 140          * Otherwise the parent must be a directory.
 141          */
 142         if (!*is_xattrdir && !S_ISDIR(parent_mode))
 143                 return (SET_ERROR(EINVAL));
 144
 145         *pobjp = parent;
 146
 147         return (0);
 148 }
 149
 150 /*
 151  * Given an object number, return some zpl level statistics
 152  */
 153 static int
 154 zfs_obj_to_stats_impl(sa_handle_t *hdl, sa_attr_type_t *sa_table,
 155     zfs_stat_t *sb)
 156 {
 157         sa_bulk_attr_t bulk[4];
 158         int count = 0;
 159
 160         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_MODE], NULL,
 161             &sb->zs_mode, sizeof (sb->zs_mode));
 162         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_GEN], NULL,
 163             &sb->zs_gen, sizeof (sb->zs_gen));
 164         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_LINKS], NULL,
 165             &sb->zs_links, sizeof (sb->zs_links));
 166         SA_ADD_BULK_ATTR(bulk, count, sa_table[ZPL_CTIME], NULL,
 167             &sb->zs_ctime, sizeof (sb->zs_ctime));
 168
 169         return (sa_bulk_lookup(hdl, bulk, count));
 170 }
 171
 172 static int
 173 zfs_obj_to_path_impl(objset_t *osp, uint64_t obj, sa_handle_t *hdl,
 174     sa_attr_type_t *sa_table, char *buf, int len)
 175 {
 176         sa_handle_t *sa_hdl;
 177         sa_handle_t *prevhdl = NULL;
 178         dmu_buf_t *prevdb = NULL;
 179         dmu_buf_t *sa_db = NULL;
 180         char *path = buf + len - 1;
 181         char *comp_buf;
 182         int error;
 183
 184         *path = '\0';
 185         sa_hdl = hdl;
 186
 187         uint64_t deleteq_obj;
 188         VERIFY0(zap_lookup(osp, MASTER_NODE_OBJ,
 189             ZFS_UNLINKED_SET, sizeof (uint64_t), 1, &deleteq_obj));
 190         error = zap_lookup_int(osp, deleteq_obj, obj);
 191         if (error == 0) {
 192                 return (ESTALE);
 193         } else if (error != ENOENT) {
 194                 return (error);
 195         }
 196
 197         comp_buf = kmem_alloc(ZAP_MAXNAMELEN_NEW + 2, KM_SLEEP);
 198         for (;;) {
 199                 uint64_t pobj = 0;
 200                 char *component = comp_buf;
 201                 size_t complen;
 202                 int is_xattrdir = 0;
 203
 204                 if (prevdb) {
 205                         ASSERT3P(prevhdl, !=, NULL);
 206                         zfs_release_sa_handle(prevhdl, prevdb, FTAG);
 207                 }
 208
 209                 if ((error = zfs_obj_to_pobj(osp, sa_hdl, sa_table, &pobj,
 210                     &is_xattrdir)) != 0)
 211                         break;
 212
 213                 if (pobj == obj) {
 214                         if (path[0] != '/')
 215                                 *--path = '/';
 216                         break;
 217                 }
 218
 219                 component[0] = '/';
 220                 if (is_xattrdir) {
 221                         strcpy(component + 1, "<xattrdir>");
 222                 } else {
 223                         error = zap_value_search(osp, pobj, obj,
 224                             ZFS_DIRENT_OBJ(-1ULL), component + 1,
 225                             ZAP_MAXNAMELEN_NEW);
 226                         if (error != 0)
 227                                 break;
 228                 }
 229
 230                 complen = strlen(component);
 231                 path -= complen;
 232                 ASSERT3P(path, >=, buf);
 233                 memcpy(path, component, complen);
 234                 obj = pobj;
 235
 236                 if (sa_hdl != hdl) {
 237                         prevhdl = sa_hdl;
 238                         prevdb = sa_db;
 239                 }
 240                 error = zfs_grab_sa_handle(osp, obj, &sa_hdl, &sa_db, FTAG);
 241                 if (error != 0) {
 242                         sa_hdl = prevhdl;
 243                         sa_db = prevdb;
 244                         break;
 245                 }
 246         }
 247
 248         if (sa_hdl != NULL && sa_hdl != hdl) {
 249                 ASSERT3P(sa_db, !=, NULL);
 250                 zfs_release_sa_handle(sa_hdl, sa_db, FTAG);
 251         }
 252
 253         if (error == 0)
 254                 (void) memmove(buf, path, buf + len - path);
 255
 256         kmem_free(comp_buf, ZAP_MAXNAMELEN_NEW +2);
 257         return (error);
 258 }
 259
 260 int
 261 zfs_obj_to_path(objset_t *osp, uint64_t obj, char *buf, int len)
 262 {
 263         sa_attr_type_t *sa_table;
 264         sa_handle_t *hdl;
 265         dmu_buf_t *db;
 266         int error;
 267
 268         error = zfs_sa_setup(osp, &sa_table);
 269         if (error != 0)
 270                 return (error);
 271
 272         error = zfs_grab_sa_handle(osp, obj, &hdl, &db, FTAG);
 273         if (error != 0)
 274                 return (error);
 275
 276         error = zfs_obj_to_path_impl(osp, obj, hdl, sa_table, buf, len);
 277
 278         zfs_release_sa_handle(hdl, db, FTAG);
 279         return (error);
 280 }
 281
 282 int
 283 zfs_obj_to_stats(objset_t *osp, uint64_t obj, zfs_stat_t *sb,
 284     char *buf, int len)
 285 {
 286         char *path = buf + len - 1;
 287         sa_attr_type_t *sa_table;
 288         sa_handle_t *hdl;
 289         dmu_buf_t *db;
 290         int error;
 291
 292         *path = '\0';
 293
 294         error = zfs_sa_setup(osp, &sa_table);
 295         if (error != 0)
 296                 return (error);
 297
 298         error = zfs_grab_sa_handle(osp, obj, &hdl, &db, FTAG);
 299         if (error != 0)
 300                 return (error);
 301
 302         error = zfs_obj_to_stats_impl(hdl, sa_table, sb);
 303         if (error != 0) {
 304                 zfs_release_sa_handle(hdl, db, FTAG);
 305                 return (error);
 306         }
 307
 308         error = zfs_obj_to_path_impl(osp, obj, hdl, sa_table, buf, len);
 309
 310         zfs_release_sa_handle(hdl, db, FTAG);
 311         return (error);
 312 }
 313
 314 /*
 315  * Read a property stored within the master node.
 316  */
 317 int
 318 zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value)
 319 {
 320         uint64_t *cached_copy = NULL;
 321
 322         /*
 323          * Figure out where in the objset_t the cached copy would live, if it
 324          * is available for the requested property.
 325          */
 326         if (os != NULL) {
 327                 switch (prop) {
 328                 case ZFS_PROP_VERSION:
 329                         cached_copy = &os->os_version;
 330                         break;
 331                 case ZFS_PROP_NORMALIZE:
 332                         cached_copy = &os->os_normalization;
 333                         break;
 334                 case ZFS_PROP_UTF8ONLY:
 335                         cached_copy = &os->os_utf8only;
 336                         break;
 337                 case ZFS_PROP_CASE:
 338                         cached_copy = &os->os_casesensitivity;
 339                         break;
 340                 default:
 341                         break;
 342                 }
 343         }
 344         if (cached_copy != NULL && *cached_copy != OBJSET_PROP_UNINITIALIZED) {
 345                 *value = *cached_copy;
 346                 return (0);
 347         }
 348
 349         /*
 350          * If the property wasn't cached, look up the file system's value for
 351          * the property. For the version property, we look up a slightly
 352          * different string.
 353          */
 354         const char *pname;
 355         int error = ENOENT;
 356         if (prop == ZFS_PROP_VERSION)
 357                 pname = ZPL_VERSION_STR;
 358         else
 359                 pname = zfs_prop_to_name(prop);
 360
 361         if (os != NULL) {
 362                 ASSERT3U(os->os_phys->os_type, ==, DMU_OST_ZFS);
 363                 error = zap_lookup(os, MASTER_NODE_OBJ, pname, 8, 1, value);
 364         }
 365
 366         if (error == ENOENT) {
 367                 /* No value set, use the default value */
 368                 switch (prop) {
 369                 case ZFS_PROP_VERSION:
 370                         *value = ZPL_VERSION;
 371                         break;
 372                 case ZFS_PROP_NORMALIZE:
 373                 case ZFS_PROP_UTF8ONLY:
 374                         *value = 0;
 375                         break;
 376                 case ZFS_PROP_CASE:
 377                         *value = ZFS_CASE_SENSITIVE;
 378                         break;
 379                 case ZFS_PROP_ACLTYPE:
 380 #ifdef __FreeBSD__
 381                         *value = ZFS_ACLTYPE_NFSV4;
 382 #else
 383                         *value = ZFS_ACLTYPE_OFF;
 384 #endif
 385                         break;
 386                 default:
 387                         return (error);
 388                 }
 389                 error = 0;
 390         }
 391
 392         /*
 393          * If one of the methods for getting the property value above worked,
 394          * copy it into the objset_t's cache.
 395          */
 396         if (error == 0 && cached_copy != NULL) {
 397                 *cached_copy = *value;
 398         }
 399
 400         return (error);
 401 }