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 /* 23 * Copyright (C) 2011 Lawrence Livermore National Security, LLC. 24 */ 25 26 #ifndef _ZFS_DCACHE_H 27 #define _ZFS_DCACHE_H 28 29 #include <linux/dcache.h> 30 31 #define dname(dentry) ((char *)((dentry)->d_name.name)) 32 #define dlen(dentry) ((int)((dentry)->d_name.len)) 33 34 #ifndef HAVE_D_MAKE_ROOT 35 #define d_make_root(inode) d_alloc_root(inode) 36 #endif /* HAVE_D_MAKE_ROOT */ 37 38 #ifdef HAVE_DENTRY_D_U_ALIASES 39 #define d_alias d_u.d_alias 40 #endif 41 42 /* 43 * 2.6.30 API change, 44 * The const keyword was added to the 'struct dentry_operations' in 45 * the dentry structure. To handle this we define an appropriate 46 * dentry_operations_t typedef which can be used. 47 */ 48 typedef const struct dentry_operations dentry_operations_t; 49 50 /* 51 * 2.6.38 API addition, 52 * Added d_clear_d_op() helper function which clears some flags and the 53 * registered dentry->d_op table. This is required because d_set_d_op() 54 * issues a warning when the dentry operations table is already set. 55 * For the .zfs control directory to work properly we must be able to 56 * override the default operations table and register custom .d_automount 57 * and .d_revalidate callbacks. 58 */ 59 static inline void 60 d_clear_d_op(struct dentry *dentry) 61 { 62 dentry->d_op = NULL; 63 dentry->d_flags &= ~( 64 DCACHE_OP_HASH | DCACHE_OP_COMPARE | 65 DCACHE_OP_REVALIDATE | DCACHE_OP_DELETE); 66 } 67 68 /* 69 * Walk and invalidate all dentry aliases of an inode 70 * unless it's a mountpoint 71 */ 72 static inline void 73 zpl_d_drop_aliases(struct inode *inode) 74 { 75 struct dentry *dentry; 76 spin_lock(&inode->i_lock); 77 hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) { 78 if (!IS_ROOT(dentry) && !d_mountpoint(dentry) && 79 (dentry->d_inode == inode)) { 80 d_drop(dentry); 81 } 82 } 83 spin_unlock(&inode->i_lock); 84 } 85 #endif /* _ZFS_DCACHE_H */ 86