xref: /haiku/src/add-ons/kernel/file_systems/fat/bsd/sys/bufobj.h (revision 342a1b221b5bb385410f758df2c625b70cafdd03)
1*342a1b22SJim906 /*-
2*342a1b22SJim906  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3*342a1b22SJim906  *
4*342a1b22SJim906  * Copyright (c) 2004 Poul-Henning Kamp
5*342a1b22SJim906  * All rights reserved.
6*342a1b22SJim906  *
7*342a1b22SJim906  * Redistribution and use in source and binary forms, with or without
8*342a1b22SJim906  * modification, are permitted provided that the following conditions
9*342a1b22SJim906  * are met:
10*342a1b22SJim906  * 1. Redistributions of source code must retain the above copyright
11*342a1b22SJim906  *    notice, this list of conditions and the following disclaimer.
12*342a1b22SJim906  * 2. Redistributions in binary form must reproduce the above copyright
13*342a1b22SJim906  *    notice, this list of conditions and the following disclaimer in the
14*342a1b22SJim906  *    documentation and/or other materials provided with the distribution.
15*342a1b22SJim906  *
16*342a1b22SJim906  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17*342a1b22SJim906  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18*342a1b22SJim906  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19*342a1b22SJim906  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20*342a1b22SJim906  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21*342a1b22SJim906  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22*342a1b22SJim906  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23*342a1b22SJim906  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24*342a1b22SJim906  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25*342a1b22SJim906  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26*342a1b22SJim906  * SUCH DAMAGE.
27*342a1b22SJim906  */
28*342a1b22SJim906 #ifndef FAT_BUFOBJ_H
29*342a1b22SJim906 #define FAT_BUFOBJ_H
30*342a1b22SJim906 
31*342a1b22SJim906 
32*342a1b22SJim906 // Modified to support the Haiku FAT driver.
33*342a1b22SJim906 
34*342a1b22SJim906 #include <sys/queue.h>
35*342a1b22SJim906 
36*342a1b22SJim906 #include "sys/_rwlock.h"
37*342a1b22SJim906 
38*342a1b22SJim906 
39*342a1b22SJim906 SLIST_HEAD(buf_list, buf);
40*342a1b22SJim906 
41*342a1b22SJim906 // For the device vnode, v_bufobj holds lists of struct bufs that are available for use
42*342a1b22SJim906 // by the functions defined in vfs_bio.c. For all other nodes, v_bufobj is not used.
43*342a1b22SJim906 struct bufobj {
44*342a1b22SJim906 	struct rwlock bo_lock;
45*342a1b22SJim906 	u_int bo_flag;
46*342a1b22SJim906 
47*342a1b22SJim906 	// Members added for Haiku port
48*342a1b22SJim906 	struct buf_list bo_clusterbufs;
49*342a1b22SJim906 		// an SLIST of buffers with b_bufsize equal to cluster size
50*342a1b22SJim906 	uint32 bo_clusters;
51*342a1b22SJim906 		// count of bufs in bo_clusterbufs
52*342a1b22SJim906 	struct buf_list bo_fatbufs;
53*342a1b22SJim906 		// SLIST of buffers of the size used to read the FAT. Currently, FAT16 and FAT32 volumes
54*342a1b22SJim906 		// read the FAT in 512-byte blocks, and this is only useful for FAT12, which reads it in
55*342a1b22SJim906 		// 1536-byte blocks.
56*342a1b22SJim906 	uint32 bo_fatblocks;
57*342a1b22SJim906 	struct buf_list bo_emptybufs;
58*342a1b22SJim906 		// SLIST of buffers with no space allocated for b_data (b_data must be set to point to a
59*342a1b22SJim906 		// block in the block cache).
60*342a1b22SJim906 	uint32 bo_empties;
61*342a1b22SJim906 };
62*342a1b22SJim906 
63*342a1b22SJim906 #define BO_LOCK(bo) rw_lock_write_lock(BO_LOCKPTR(bo))
64*342a1b22SJim906 #define BO_UNLOCK(bo) rw_lock_write_unlock(BO_LOCKPTR(bo))
65*342a1b22SJim906 
66*342a1b22SJim906 
67*342a1b22SJim906 #endif // FAT_BUFOBJ_H
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