xref: /xnu-10002.41.9/iokit/IOKit/IOCommand.h (revision 699cd48037512bf4380799317ca44ca453c82f57)
1*699cd480SApple OSS Distributions /*
2*699cd480SApple OSS Distributions  * Copyright (c) 2019 Apple Inc. All rights reserved.
3*699cd480SApple OSS Distributions  *
4*699cd480SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*699cd480SApple OSS Distributions  *
6*699cd480SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*699cd480SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*699cd480SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*699cd480SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*699cd480SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*699cd480SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*699cd480SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*699cd480SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*699cd480SApple OSS Distributions  *
15*699cd480SApple OSS Distributions  * Please obtain a copy of the License at
16*699cd480SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*699cd480SApple OSS Distributions  *
18*699cd480SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*699cd480SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*699cd480SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*699cd480SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*699cd480SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*699cd480SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*699cd480SApple OSS Distributions  * limitations under the License.
25*699cd480SApple OSS Distributions  *
26*699cd480SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*699cd480SApple OSS Distributions  */
28*699cd480SApple OSS Distributions 
29*699cd480SApple OSS Distributions /*
30*699cd480SApple OSS Distributions  *
31*699cd480SApple OSS Distributions  *	Copyright (c) 2000 Apple Computer, Inc.  All rights reserved.
32*699cd480SApple OSS Distributions  *
33*699cd480SApple OSS Distributions  *	HISTORY
34*699cd480SApple OSS Distributions  *
35*699cd480SApple OSS Distributions  *	2001-01-18 gvdl	Made the primary queue pointer public, to be used when
36*699cd480SApple OSS Distributions  *			Ownership is clear.
37*699cd480SApple OSS Distributions  *	11/13/2000 CJS	Created IOCommand class and implementation
38*699cd480SApple OSS Distributions  *
39*699cd480SApple OSS Distributions  */
40*699cd480SApple OSS Distributions 
41*699cd480SApple OSS Distributions /*!
42*699cd480SApple OSS Distributions  * @header IOCommand
43*699cd480SApple OSS Distributions  * @abstract
44*699cd480SApple OSS Distributions  * This header contains the IOCommand class definition.
45*699cd480SApple OSS Distributions  */
46*699cd480SApple OSS Distributions 
47*699cd480SApple OSS Distributions #ifndef _IOKIT_IO_COMMAND_H_
48*699cd480SApple OSS Distributions #define _IOKIT_IO_COMMAND_H_
49*699cd480SApple OSS Distributions 
50*699cd480SApple OSS Distributions /*
51*699cd480SApple OSS Distributions  * Kernel
52*699cd480SApple OSS Distributions  */
53*699cd480SApple OSS Distributions 
54*699cd480SApple OSS Distributions #if defined(KERNEL) && defined(__cplusplus)
55*699cd480SApple OSS Distributions 
56*699cd480SApple OSS Distributions #include <kern/queue.h>
57*699cd480SApple OSS Distributions #include <libkern/c++/OSObject.h>
58*699cd480SApple OSS Distributions 
59*699cd480SApple OSS Distributions /*!
60*699cd480SApple OSS Distributions  * @class IOCommand
61*699cd480SApple OSS Distributions  * @abstract
62*699cd480SApple OSS Distributions  * This class is an abstract class which represents an I/O command.
63*699cd480SApple OSS Distributions  * @discussion
64*699cd480SApple OSS Distributions  * This class is an abstract class which represents an I/O command passed
65*699cd480SApple OSS Distributions  * from a device driver to a controller. All controller commands (e.g. IOATACommand)
66*699cd480SApple OSS Distributions  * should inherit from this class.
67*699cd480SApple OSS Distributions  */
68*699cd480SApple OSS Distributions 
69*699cd480SApple OSS Distributions class IOCommand : public OSObject
70*699cd480SApple OSS Distributions {
71*699cd480SApple OSS Distributions 	OSDeclareDefaultStructors(IOCommand);
72*699cd480SApple OSS Distributions 
73*699cd480SApple OSS Distributions public:
74*699cd480SApple OSS Distributions 	virtual bool init(void) APPLE_KEXT_OVERRIDE;
75*699cd480SApple OSS Distributions 
76*699cd480SApple OSS Distributions /*! @var fCommandChain
77*699cd480SApple OSS Distributions  *   This variable is used by the current 'owner' to queue the command.  During the life cycle of a command it moves through a series of queues.  This is the queue pointer for it.  Only valid while 'ownership' is clear.  For instance a IOCommandPool uses this pointer to maintain its list of free commands.  May be manipulated using the kern/queue.h macros */
78*699cd480SApple OSS Distributions 	queue_chain_t fCommandChain;    /* used to queue commands */
79*699cd480SApple OSS Distributions };
80*699cd480SApple OSS Distributions 
81*699cd480SApple OSS Distributions #endif /* defined(KERNEL) && defined(__cplusplus) */
82*699cd480SApple OSS Distributions 
83*699cd480SApple OSS Distributions #endif  /* _IOKIT_IO_COMMAND_H_ */
84