1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * CDDL HEADER START
4 *
5 * The contents of this file are subject to the terms of the
6 * Common Development and Distribution License (the "License").
7 * You may not use this file except in compliance with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or https://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23 /*
24 * Copyright (C) 2011 Lawrence Livermore National Security, LLC.
25 */
26
27 #ifndef _ZFS_DCACHE_H
28 #define _ZFS_DCACHE_H
29
30 #include <linux/dcache.h>
31
32 #define dname(dentry) ((char *)((dentry)->d_name.name))
33 #define dlen(dentry) ((int)((dentry)->d_name.len))
34
35 #ifdef HAVE_DENTRY_D_U_ALIASES
36 #define d_alias d_u.d_alias
37 #endif
38
39 #ifdef HAVE_MM_PAGE_FLAGS_STRUCT
40 /*
41 * Starting from Linux 6.18, the 'flags' field in 'struct page' is defined
42 * to a struct ('memdesc_flags_t' typedef) instead of an unsigned long for
43 * improved typesafety.
44 */
45 #define page_flags flags.f
46 #else
47 #define page_flags flags
48 #endif
49
50 /*
51 * Starting from Linux 5.13, flush_dcache_page() becomes an inline function
52 * and under some configurations, may indirectly referencing GPL-only
53 * symbols, e.g., cpu_feature_keys on powerpc and PageHuge on riscv.
54 * Override this function when it is detected being GPL-only.
55 */
56 #if defined __powerpc__ && defined HAVE_FLUSH_DCACHE_PAGE_GPL_ONLY
57 #include <linux/simd_powerpc.h>
58 #define flush_dcache_page(page) do { \
59 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) && \
60 test_bit(PG_dcache_clean, &(page)->page_flags)) \
61 clear_bit(PG_dcache_clean, &(page)->page_flags);\
62 } while (0)
63 #endif
64 /*
65 * For riscv implementation, the use of PageHuge can be safely removed.
66 * Because it handles pages allocated by HugeTLB, while flush_dcache_page
67 * in zfs module is only called on kernel pages.
68 */
69 #if defined __riscv && defined HAVE_FLUSH_DCACHE_PAGE_GPL_ONLY
70 #define flush_dcache_page(page) do { \
71 if (test_bit(PG_dcache_clean, &(page)->page_flags)) \
72 clear_bit(PG_dcache_clean, &(page)->page_flags);\
73 } while (0)
74 #endif
75
76 /*
77 * Walk and invalidate all dentry aliases of an inode
78 * unless it's a mountpoint
79 */
80 static inline void
zpl_d_drop_aliases(struct inode * inode)81 zpl_d_drop_aliases(struct inode *inode)
82 {
83 struct dentry *dentry;
84 spin_lock(&inode->i_lock);
85 hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) {
86 if (!IS_ROOT(dentry) && !d_mountpoint(dentry) &&
87 (dentry->d_inode == inode)) {
88 d_drop(dentry);
89 }
90 }
91 spin_unlock(&inode->i_lock);
92 }
93 #endif /* _ZFS_DCACHE_H */
94