1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * This file and its contents are supplied under the terms of the 4 * Common Development and Distribution License ("CDDL"), version 1.0. 5 * You may only use this file in accordance with the terms of version 6 * 1.0 of the CDDL. 7 * 8 * A full copy of the text of the CDDL should have accompanied this 9 * source. A copy of the CDDL is also available via the Internet at 10 * https://opensource.org/license/CDDL-1.0. 11 */ 12 /* 13 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 14 * Use is subject to license terms. 15 */ 16 /* 17 * Copyright (c) 2018 by Delphix. All rights reserved. 18 */ 19 20 #ifndef _SYS_FS_ZFS_RLOCK_H 21 #define _SYS_FS_ZFS_RLOCK_H 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 #include <sys/avl.h> 28 29 typedef enum { 30 RL_READER, 31 RL_WRITER, 32 RL_APPEND 33 } zfs_rangelock_type_t; 34 35 struct zfs_locked_range; 36 37 typedef void (zfs_rangelock_cb_t)(struct zfs_locked_range *, void *); 38 39 typedef struct zfs_rangelock { 40 avl_tree_t rl_tree; /* contains locked_range_t */ 41 kmutex_t rl_lock; 42 zfs_rangelock_cb_t *rl_cb; 43 void *rl_arg; 44 } zfs_rangelock_t; 45 46 typedef struct zfs_locked_range { 47 zfs_rangelock_t *lr_rangelock; /* rangelock that this lock applies to */ 48 avl_node_t lr_node; /* avl node link */ 49 uint64_t lr_offset; /* file range offset */ 50 uint64_t lr_length; /* file range length */ 51 uint_t lr_count; /* range reference count in tree */ 52 zfs_rangelock_type_t lr_type; /* range type */ 53 kcondvar_t lr_write_cv; /* cv for waiting writers */ 54 kcondvar_t lr_read_cv; /* cv for waiting readers */ 55 uint8_t lr_proxy; /* acting for original range */ 56 uint8_t lr_write_wanted; /* writer wants to lock this range */ 57 uint8_t lr_read_wanted; /* reader wants to lock this range */ 58 } zfs_locked_range_t; 59 60 void zfs_rangelock_init(zfs_rangelock_t *, zfs_rangelock_cb_t *, void *); 61 void zfs_rangelock_fini(zfs_rangelock_t *); 62 63 zfs_locked_range_t *zfs_rangelock_enter(zfs_rangelock_t *, 64 uint64_t, uint64_t, zfs_rangelock_type_t); 65 zfs_locked_range_t *zfs_rangelock_tryenter(zfs_rangelock_t *, 66 uint64_t, uint64_t, zfs_rangelock_type_t); 67 void zfs_rangelock_exit(zfs_locked_range_t *); 68 void zfs_rangelock_reduce(zfs_locked_range_t *, uint64_t, uint64_t); 69 70 #ifdef __cplusplus 71 } 72 #endif 73 74 #endif /* _SYS_FS_ZFS_RLOCK_H */ 75