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 * Starting from Linux 5.13, flush_dcache_page() becomes an inline function 44 * and under some configurations, may indirectly referencing GPL-only 45 * cpu_feature_keys on powerpc. Override this function when it is detected 46 * being GPL-only. 47 */ 48 #if defined __powerpc__ && defined HAVE_FLUSH_DCACHE_PAGE_GPL_ONLY 49 #include <linux/simd_powerpc.h> 50 #define flush_dcache_page(page) do { \ 51 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) && \ 52 test_bit(PG_dcache_clean, &(page)->flags)) \ 53 clear_bit(PG_dcache_clean, &(page)->flags); \ 54 } while (0) 55 #endif 56 57 /* 58 * 2.6.30 API change, 59 * The const keyword was added to the 'struct dentry_operations' in 60 * the dentry structure. To handle this we define an appropriate 61 * dentry_operations_t typedef which can be used. 62 */ 63 typedef const struct dentry_operations dentry_operations_t; 64 65 /* 66 * 2.6.38 API addition, 67 * Added d_clear_d_op() helper function which clears some flags and the 68 * registered dentry->d_op table. This is required because d_set_d_op() 69 * issues a warning when the dentry operations table is already set. 70 * For the .zfs control directory to work properly we must be able to 71 * override the default operations table and register custom .d_automount 72 * and .d_revalidate callbacks. 73 */ 74 static inline void 75 d_clear_d_op(struct dentry *dentry) 76 { 77 dentry->d_op = NULL; 78 dentry->d_flags &= ~( 79 DCACHE_OP_HASH | DCACHE_OP_COMPARE | 80 DCACHE_OP_REVALIDATE | DCACHE_OP_DELETE); 81 } 82 83 /* 84 * Walk and invalidate all dentry aliases of an inode 85 * unless it's a mountpoint 86 */ 87 static inline void 88 zpl_d_drop_aliases(struct inode *inode) 89 { 90 struct dentry *dentry; 91 spin_lock(&inode->i_lock); 92 hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) { 93 if (!IS_ROOT(dentry) && !d_mountpoint(dentry) && 94 (dentry->d_inode == inode)) { 95 d_drop(dentry); 96 } 97 } 98 spin_unlock(&inode->i_lock); 99 } 100 #endif /* _ZFS_DCACHE_H */ 101