freebsd-nq/include/sys/dmu_zfetch.h
Shen Yan 5cb65efe2c Fix zstream_t incorrect type
The DMU zfetch code organizes streams with lists not avl trees.  A
avl_node_t was mistakenly used for a list_node_t in the zstream_t
type.  This is incorrect (but harmless) and when unnoticed because:

1) The list functions explicitly cast the value preventing a warning,
2) sizeof(avl_node_t) >= sizeof(list_node_t) so no overrun occurs, and
3) The calculated offset is the same regardless of the type.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1946
2013-12-10 10:09:27 -08:00

77 lines
2.3 KiB
C

/*
* 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 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _DFETCH_H
#define _DFETCH_H
#include <sys/zfs_context.h>
#ifdef __cplusplus
extern "C" {
#endif
extern unsigned long zfetch_array_rd_sz;
struct dnode; /* so we can reference dnode */
typedef enum zfetch_dirn {
ZFETCH_FORWARD = 1, /* prefetch increasing block numbers */
ZFETCH_BACKWARD = -1 /* prefetch decreasing block numbers */
} zfetch_dirn_t;
typedef struct zstream {
uint64_t zst_offset; /* offset of starting block in range */
uint64_t zst_len; /* length of range, in blocks */
zfetch_dirn_t zst_direction; /* direction of prefetch */
uint64_t zst_stride; /* length of stride, in blocks */
uint64_t zst_ph_offset; /* prefetch offset, in blocks */
uint64_t zst_cap; /* prefetch limit (cap), in blocks */
kmutex_t zst_lock; /* protects stream */
clock_t zst_last; /* lbolt of last prefetch */
list_node_t zst_node; /* next zstream here */
} zstream_t;
typedef struct zfetch {
krwlock_t zf_rwlock; /* protects zfetch structure */
list_t zf_stream; /* AVL tree of zstream_t's */
struct dnode *zf_dnode; /* dnode that owns this zfetch */
uint32_t zf_stream_cnt; /* # of active streams */
uint64_t zf_alloc_fail; /* # of failed attempts to alloc strm */
} zfetch_t;
void zfetch_init(void);
void zfetch_fini(void);
void dmu_zfetch_init(zfetch_t *, struct dnode *);
void dmu_zfetch_rele(zfetch_t *);
void dmu_zfetch(zfetch_t *, uint64_t, uint64_t, int);
#ifdef __cplusplus
}
#endif
#endif /* _DFETCH_H */