zfs/include/linux/vfs_compat.h

   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 http://www.opensolaris.org/os/licensing.
  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 /*
  23  * Copyright (C) 2011 Lawrence Livermore National Security, LLC.
  24  * Copyright (C) 2015 Jörg Thalheim.
  25  */
  26
  27 #ifndef _ZFS_VFS_H
  28 #define _ZFS_VFS_H
  29
  30 #include <sys/taskq.h>
  31 #include <linux/backing-dev.h>
  32
  33 /*
  34  * 2.6.28 API change,
  35  * Added insert_inode_locked() helper function, prior to this most callers
  36  * used insert_inode_hash().  The older method doesn't check for collisions
  37  * in the inode_hashtable but it still acceptible for use.
  38  */
  39 #ifndef HAVE_INSERT_INODE_LOCKED
  40 static inline int
  41 insert_inode_locked(struct inode *ip)
  42 {
  43         insert_inode_hash(ip);
  44         return (0);
  45 }
  46 #endif /* HAVE_INSERT_INODE_LOCKED */
  47
  48 /*
  49  * 2.6.35 API change,
  50  * Add truncate_setsize() if it is not exported by the Linux kernel.
  51  *
  52  * Truncate the inode and pages associated with the inode. The pages are
  53  * unmapped and removed from cache.
  54  */
  55 #ifndef HAVE_TRUNCATE_SETSIZE
  56 static inline void
  57 truncate_setsize(struct inode *ip, loff_t new)
  58 {
  59         struct address_space *mapping = ip->i_mapping;
  60
  61         i_size_write(ip, new);
  62
  63         unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1);
  64         truncate_inode_pages(mapping, new);
  65         unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1);
  66 }
  67 #endif /* HAVE_TRUNCATE_SETSIZE */
  68
  69 /*
  70  * 2.6.32 - 2.6.33, bdi_setup_and_register() is not available.
  71  * 2.6.34 - 3.19, bdi_setup_and_register() takes 3 arguments.
  72  * 4.0 - x.y, bdi_setup_and_register() takes 2 arguments.
  73  */
  74 #if defined(HAVE_2ARGS_BDI_SETUP_AND_REGISTER)
  75 static inline int
  76 zpl_bdi_setup_and_register(struct backing_dev_info *bdi, char *name)
  77 {
  78         return (bdi_setup_and_register(bdi, name));
  79 }
  80 #elif defined(HAVE_3ARGS_BDI_SETUP_AND_REGISTER)
  81 static inline int
  82 zpl_bdi_setup_and_register(struct backing_dev_info *bdi, char *name)
  83 {
  84         return (bdi_setup_and_register(bdi, name, BDI_CAP_MAP_COPY));
  85 }
  86 #else
  87 extern atomic_long_t zfs_bdi_seq;
  88
  89 static inline int
  90 zpl_bdi_setup_and_register(struct backing_dev_info *bdi, char *name)
  91 {
  92         char tmp[32];
  93         int error;
  94
  95         bdi->name = name;
  96         bdi->capabilities = BDI_CAP_MAP_COPY;
  97
  98         error = bdi_init(bdi);
  99         if (error)
 100                 return (error);
 101
 102         sprintf(tmp, "%.28s%s", name, "-%d");
 103         error = bdi_register(bdi, NULL, tmp,
 104             atomic_long_inc_return(&zfs_bdi_seq));
 105         if (error) {
 106                 bdi_destroy(bdi);
 107                 return (error);
 108         }
 109
 110         return (error);
 111 }
 112 #endif
 113
 114 /*
 115  * 2.6.38 API change,
 116  * LOOKUP_RCU flag introduced to distinguish rcu-walk from ref-walk cases.
 117  */
 118 #ifndef LOOKUP_RCU
 119 #define LOOKUP_RCU      0x0
 120 #endif /* LOOKUP_RCU */
 121
 122 /*
 123  * 3.2-rc1 API change,
 124  * Add set_nlink() if it is not exported by the Linux kernel.
 125  *
 126  * i_nlink is read-only in Linux 3.2, but it can be set directly in
 127  * earlier kernels.
 128  */
 129 #ifndef HAVE_SET_NLINK
 130 static inline void
 131 set_nlink(struct inode *inode, unsigned int nlink)
 132 {
 133         inode->i_nlink = nlink;
 134 }
 135 #endif /* HAVE_SET_NLINK */
 136
 137 /*
 138  * 3.3 API change,
 139  * The VFS .create, .mkdir and .mknod callbacks were updated to take a
 140  * umode_t type rather than an int.  To cleanly handle both definitions
 141  * the zpl_umode_t type is introduced and set accordingly.
 142  */
 143 #ifdef HAVE_MKDIR_UMODE_T
 144 typedef umode_t         zpl_umode_t;
 145 #else
 146 typedef int             zpl_umode_t;
 147 #endif
 148
 149 /*
 150  * 3.5 API change,
 151  * The clear_inode() function replaces end_writeback() and introduces an
 152  * ordering change regarding when the inode_sync_wait() occurs.  See the
 153  * configure check in config/kernel-clear-inode.m4 for full details.
 154  */
 155 #if defined(HAVE_EVICT_INODE) && !defined(HAVE_CLEAR_INODE)
 156 #define clear_inode(ip)         end_writeback(ip)
 157 #endif /* HAVE_EVICT_INODE && !HAVE_CLEAR_INODE */
 158
 159 /*
 160  * 3.6 API change,
 161  * The sget() helper function now takes the mount flags as an argument.
 162  */
 163 #ifdef HAVE_5ARG_SGET
 164 #define zpl_sget(type, cmp, set, fl, mtd)       sget(type, cmp, set, fl, mtd)
 165 #else
 166 #define zpl_sget(type, cmp, set, fl, mtd)       sget(type, cmp, set, mtd)
 167 #endif /* HAVE_5ARG_SGET */
 168
 169 #if defined(SEEK_HOLE) && defined(SEEK_DATA) && !defined(HAVE_LSEEK_EXECUTE)
 170 static inline loff_t
 171 lseek_execute(
 172         struct file *filp,
 173         struct inode *inode,
 174         loff_t offset,
 175         loff_t maxsize)
 176 {
 177         if (offset < 0 && !(filp->f_mode & FMODE_UNSIGNED_OFFSET))
 178                 return (-EINVAL);
 179
 180         if (offset > maxsize)
 181                 return (-EINVAL);
 182
 183         if (offset != filp->f_pos) {
 184                 spin_lock(&filp->f_lock);
 185                 filp->f_pos = offset;
 186                 filp->f_version = 0;
 187                 spin_unlock(&filp->f_lock);
 188         }
 189
 190         return (offset);
 191 }
 192 #endif /* SEEK_HOLE && SEEK_DATA && !HAVE_LSEEK_EXECUTE */
 193
 194 #if defined(CONFIG_FS_POSIX_ACL)
 195 /*
 196  * These functions safely approximates the behavior of posix_acl_release()
 197  * which cannot be used because it calls the GPL-only symbol kfree_rcu().
 198  * The in-kernel version, which can access the RCU, frees the ACLs after
 199  * the grace period expires.  Because we're unsure how long that grace
 200  * period may be this implementation conservatively delays for 60 seconds.
 201  * This is several orders of magnitude larger than expected grace period.
 202  * At 60 seconds the kernel will also begin issuing RCU stall warnings.
 203  */
 204 #include <linux/posix_acl.h>
 205
 206 #if defined(HAVE_POSIX_ACL_RELEASE) && !defined(HAVE_POSIX_ACL_RELEASE_GPL_ONLY)
 207
 208 #define zpl_posix_acl_release(arg)              posix_acl_release(arg)
 209 #define zpl_set_cached_acl(ip, ty, n)           set_cached_acl(ip, ty, n)
 210 #define zpl_forget_cached_acl(ip, ty)           forget_cached_acl(ip, ty)
 211
 212 #else
 213
 214 static inline void
 215 zpl_posix_acl_free(void *arg) {
 216         kfree(arg);
 217 }
 218
 219 static inline void
 220 zpl_posix_acl_release(struct posix_acl *acl)
 221 {
 222         if ((acl == NULL) || (acl == ACL_NOT_CACHED))
 223                 return;
 224
 225         if (atomic_dec_and_test(&acl->a_refcount)) {
 226                 taskq_dispatch_delay(system_taskq, zpl_posix_acl_free, acl,
 227                     TQ_SLEEP, ddi_get_lbolt() + 60*HZ);
 228         }
 229 }
 230
 231 static inline void
 232 zpl_set_cached_acl(struct inode *ip, int type, struct posix_acl *newer) {
 233         struct posix_acl *older = NULL;
 234
 235         spin_lock(&ip->i_lock);
 236
 237         if ((newer != ACL_NOT_CACHED) && (newer != NULL))
 238                 posix_acl_dup(newer);
 239
 240         switch (type) {
 241         case ACL_TYPE_ACCESS:
 242                 older = ip->i_acl;
 243                 rcu_assign_pointer(ip->i_acl, newer);
 244                 break;
 245         case ACL_TYPE_DEFAULT:
 246                 older = ip->i_default_acl;
 247                 rcu_assign_pointer(ip->i_default_acl, newer);
 248                 break;
 249         }
 250
 251         spin_unlock(&ip->i_lock);
 252
 253         zpl_posix_acl_release(older);
 254 }
 255
 256 static inline void
 257 zpl_forget_cached_acl(struct inode *ip, int type) {
 258         zpl_set_cached_acl(ip, type, (struct posix_acl *)ACL_NOT_CACHED);
 259 }
 260 #endif /* HAVE_POSIX_ACL_RELEASE */
 261
 262 #ifndef HAVE___POSIX_ACL_CHMOD
 263 #ifdef HAVE_POSIX_ACL_CHMOD
 264 #define __posix_acl_chmod(acl, gfp, mode)       posix_acl_chmod(acl, gfp, mode)
 265 #define __posix_acl_create(acl, gfp, mode)      posix_acl_create(acl, gfp, mode)
 266 #else
 267 static inline int
 268 __posix_acl_chmod(struct posix_acl **acl, int flags, umode_t umode) {
 269         struct posix_acl *oldacl = *acl;
 270         mode_t mode = umode;
 271         int error;
 272
 273         *acl = posix_acl_clone(*acl, flags);
 274         zpl_posix_acl_release(oldacl);
 275
 276         if (!(*acl))
 277                 return (-ENOMEM);
 278
 279         error = posix_acl_chmod_masq(*acl, mode);
 280         if (error) {
 281                 zpl_posix_acl_release(*acl);
 282                 *acl = NULL;
 283         }
 284
 285         return (error);
 286 }
 287
 288 static inline int
 289 __posix_acl_create(struct posix_acl **acl, int flags, umode_t *umodep) {
 290         struct posix_acl *oldacl = *acl;
 291         mode_t mode = *umodep;
 292         int error;
 293
 294         *acl = posix_acl_clone(*acl, flags);
 295         zpl_posix_acl_release(oldacl);
 296
 297         if (!(*acl))
 298                 return (-ENOMEM);
 299
 300         error = posix_acl_create_masq(*acl, &mode);
 301         *umodep = mode;
 302
 303         if (error < 0) {
 304                 zpl_posix_acl_release(*acl);
 305                 *acl = NULL;
 306         }
 307
 308         return (error);
 309 }
 310 #endif /* HAVE_POSIX_ACL_CHMOD */
 311 #endif /* HAVE___POSIX_ACL_CHMOD */
 312
 313 #ifdef HAVE_POSIX_ACL_EQUIV_MODE_UMODE_T
 314 typedef umode_t zpl_equivmode_t;
 315 #else
 316 typedef mode_t zpl_equivmode_t;
 317 #endif /* HAVE_POSIX_ACL_EQUIV_MODE_UMODE_T */
 318
 319 /*
 320  * 4.8 API change,
 321  * posix_acl_valid() now must be passed a namespace, the namespace from
 322  * from super block associated with the given inode is used for this purpose.
 323  */
 324 #ifdef HAVE_POSIX_ACL_VALID_WITH_NS
 325 #define zpl_posix_acl_valid(ip, acl)  posix_acl_valid(ip->i_sb->s_user_ns, acl)
 326 #else
 327 #define zpl_posix_acl_valid(ip, acl)  posix_acl_valid(acl)
 328 #endif
 329
 330 #endif /* CONFIG_FS_POSIX_ACL */
 331
 332 /*
 333  * 2.6.38 API change,
 334  * The is_owner_or_cap() function was renamed to inode_owner_or_capable().
 335  */
 336 #ifdef HAVE_INODE_OWNER_OR_CAPABLE
 337 #define zpl_inode_owner_or_capable(ip)          inode_owner_or_capable(ip)
 338 #else
 339 #define zpl_inode_owner_or_capable(ip)          is_owner_or_cap(ip)
 340 #endif /* HAVE_INODE_OWNER_OR_CAPABLE */
 341
 342 /*
 343  * 3.19 API change
 344  * struct access f->f_dentry->d_inode was replaced by accessor function
 345  * file_inode(f)
 346  */
 347 #ifndef HAVE_FILE_INODE
 348 static inline struct inode *file_inode(const struct file *f)
 349 {
 350         return (f->f_dentry->d_inode);
 351 }
 352 #endif /* HAVE_FILE_INODE */
 353
 354 /*
 355  * 2.6.38 API change
 356  */
 357 #ifdef HAVE_FOLLOW_DOWN_ONE
 358 #define zpl_follow_down_one(path)               follow_down_one(path)
 359 #define zpl_follow_up(path)                     follow_up(path)
 360 #else
 361 #define zpl_follow_down_one(path)               follow_down(path)
 362 #define zpl_follow_up(path)                     follow_up(path)
 363 #endif
 364
 365 #endif /* _ZFS_VFS_H */