projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| b6450630 SF |
1 | /* |
| 2 | * Copyright (C) 2005-2017 Junjiro R. Okajima | |
| 3 | * | |
| 4 | * This program, aufs is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License as published by | |
| 6 | * the Free Software Foundation; either version 2 of the License, or | |
| 7 | * (at your option) any later version. | |
| 8 | * | |
| 9 | * This program is distributed in the hope that it will be useful, | |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 | * GNU General Public License for more details. | |
| 13 | * | |
| 14 | * You should have received a copy of the GNU General Public License | |
| 15 | * along with this program. If not, see <http://www.gnu.org/licenses/>. | |
| 16 | */ | |
| 17 | ||
| 18 | /* | |
| 19 | * workqueue for asynchronous/super-io operations | |
| 20 | * todo: try new credentials management scheme | |
| 21 | */ | |
| 22 | ||
| 23 | #ifndef __AUFS_WKQ_H__ | |
| 24 | #define __AUFS_WKQ_H__ | |
| 25 | ||
| 26 | #ifdef __KERNEL__ | |
| 27 | ||
| 28 | #include <linux/percpu_counter.h> | |
| 29 | ||
| 30 | struct super_block; | |
| 31 | ||
| 32 | /* ---------------------------------------------------------------------- */ | |
| 33 | ||
| 34 | /* | |
| 35 | * in the next operation, wait for the 'nowait' tasks in system-wide workqueue | |
| 36 | */ | |
| 37 | struct au_nowait_tasks { | |
| 38 | atomic_t nw_len; | |
| 39 | wait_queue_head_t nw_wq; | |
| 40 | }; | |
| 41 | ||
| 42 | /* ---------------------------------------------------------------------- */ | |
| 43 | ||
| 44 | typedef void (*au_wkq_func_t)(void *args); | |
| 45 | ||
| 46 | /* wkq flags */ | |
| 47 | #define AuWkq_WAIT 1 | |
| 48 | #define AuWkq_NEST (1 << 1) | |
| 49 | #define au_ftest_wkq(flags, name) ((flags) & AuWkq_##name) | |
| 50 | #define au_fset_wkq(flags, name) \ | |
| 51 | do { (flags) |= AuWkq_##name; } while (0) | |
| 52 | #define au_fclr_wkq(flags, name) \ | |
| 53 | do { (flags) &= ~AuWkq_##name; } while (0) | |
| 54 | ||
| 55 | #ifndef CONFIG_AUFS_HNOTIFY | |
| 56 | #undef AuWkq_NEST | |
| 57 | #define AuWkq_NEST 0 | |
| 58 | #endif | |
| 59 | ||
| 60 | /* wkq.c */ | |
| 61 | int au_wkq_do_wait(unsigned int flags, au_wkq_func_t func, void *args); | |
| 62 | int au_wkq_nowait(au_wkq_func_t func, void *args, struct super_block *sb, | |
| 63 | unsigned int flags); | |
| 64 | void au_nwt_init(struct au_nowait_tasks *nwt); | |
| 65 | int __init au_wkq_init(void); | |
| 66 | void au_wkq_fin(void); | |
| 67 | ||
| 68 | /* ---------------------------------------------------------------------- */ | |
| 69 | ||
| 70 | static inline int au_wkq_test(void) | |
| 71 | { | |
| 72 | return current->flags & PF_WQ_WORKER; | |
| 73 | } | |
| 74 | ||
| 75 | static inline int au_wkq_wait(au_wkq_func_t func, void *args) | |
| 76 | { | |
| 77 | return au_wkq_do_wait(AuWkq_WAIT, func, args); | |
| 78 | } | |
| 79 | ||
| 80 | static inline void au_nwt_done(struct au_nowait_tasks *nwt) | |
| 81 | { | |
| 82 | if (atomic_dec_and_test(&nwt->nw_len)) | |
| 83 | wake_up_all(&nwt->nw_wq); | |
| 84 | } | |
| 85 | ||
| 86 | static inline int au_nwt_flush(struct au_nowait_tasks *nwt) | |
| 87 | { | |
| 88 | wait_event(nwt->nw_wq, !atomic_read(&nwt->nw_len)); | |
| 89 | return 0; | |
| 90 | } | |
| 91 | ||
| 92 | #endif /* __KERNEL__ */ | |
| 93 | #endif /* __AUFS_WKQ_H__ */ |