diff options
Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_rlock.h')
-rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_rlock.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_rlock.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_rlock.h new file mode 100644 index 0000000..93733ba --- /dev/null +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zfs_rlock.h @@ -0,0 +1,86 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2006 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#ifndef _SYS_FS_ZFS_RLOCK_H +#define _SYS_FS_ZFS_RLOCK_H + +#ifdef __cplusplus +extern "C" { +#endif + +#ifdef _KERNEL + +#include <sys/zfs_znode.h> + +typedef enum { + RL_READER, + RL_WRITER, + RL_APPEND +} rl_type_t; + +typedef struct rl { + znode_t *r_zp; /* znode this lock applies to */ + avl_node_t r_node; /* avl node link */ + uint64_t r_off; /* file range offset */ + uint64_t r_len; /* file range length */ + uint_t r_cnt; /* range reference count in tree */ + rl_type_t r_type; /* range type */ + kcondvar_t r_wr_cv; /* cv for waiting writers */ + kcondvar_t r_rd_cv; /* cv for waiting readers */ + uint8_t r_proxy; /* acting for original range */ + uint8_t r_write_wanted; /* writer wants to lock this range */ + uint8_t r_read_wanted; /* reader wants to lock this range */ +} rl_t; + +/* + * Lock a range (offset, length) as either shared (RL_READER) + * or exclusive (RL_WRITER or RL_APPEND). RL_APPEND is a special type that + * is converted to RL_WRITER that specified to lock from the start of the + * end of file. Returns the range lock structure. + */ +rl_t *zfs_range_lock(znode_t *zp, uint64_t off, uint64_t len, rl_type_t type); + +/* Unlock range and destroy range lock structure. */ +void zfs_range_unlock(rl_t *rl); + +/* + * Reduce range locked as RW_WRITER from whole file to specified range. + * Asserts the whole file was previously locked. + */ +void zfs_range_reduce(rl_t *rl, uint64_t off, uint64_t len); + +/* + * AVL comparison function used to order range locks + * Locks are ordered on the start offset of the range. + */ +int zfs_range_compare(const void *arg1, const void *arg2); + +#endif /* _KERNEL */ + +#ifdef __cplusplus +} +#endif + +#endif /* _SYS_FS_ZFS_RLOCK_H */ |