1/*
2 *	Block OSM structures/API
3 *
4 * 	Copyright (C) 1999-2002	Red Hat Software
5 *
6 *	Written by Alan Cox, Building Number Three Ltd
7 *
8 *	This program is free software; you can redistribute it and/or modify it
9 *	under the terms of the GNU General Public License as published by the
10 *	Free Software Foundation; either version 2 of the License, or (at your
11 *	option) any later version.
12 *
13 *	This program is distributed in the hope that it will be useful, but
14 *	WITHOUT ANY WARRANTY; without even the implied warranty of
15 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 *	General Public License for more details.
17 *
18 *	For the purpose of avoiding doubt the preferred form of the work
19 *	for making modifications shall be a standards compliant form such
20 *	gzipped tar and not one requiring a proprietary or patent encumbered
21 *	tool to unpack.
22 *
23 *	Fixes/additions:
24 *		Steve Ralston:
25 *			Multiple device handling error fixes,
26 *			Added a queue depth.
27 *		Alan Cox:
28 *			FC920 has an rmw bug. Dont or in the end marker.
29 *			Removed queue walk, fixed for 64bitness.
30 *			Rewrote much of the code over time
31 *			Added indirect block lists
32 *			Handle 64K limits on many controllers
33 *			Don't use indirects on the Promise (breaks)
34 *			Heavily chop down the queue depths
35 *		Deepak Saxena:
36 *			Independent queues per IOP
37 *			Support for dynamic device creation/deletion
38 *			Code cleanup
39 *	    		Support for larger I/Os through merge* functions
40 *			(taken from DAC960 driver)
41 *		Boji T Kannanthanam:
42 *			Set the I2O Block devices to be detected in increasing
43 *			order of TIDs during boot.
44 *			Search and set the I2O block device that we boot off
45 *			from as the first device to be claimed (as /dev/i2o/hda)
46 *			Properly attach/detach I2O gendisk structure from the
47 *			system gendisk list. The I2O block devices now appear in
48 *			/proc/partitions.
49 *		Markus Lidel <Markus.Lidel@shadowconnect.com>:
50 *			Minor bugfixes for 2.6.
51 */
52
53#ifndef I2O_BLOCK_OSM_H
54#define I2O_BLOCK_OSM_H
55
56#define I2O_BLOCK_RETRY_TIME HZ/4
57#define I2O_BLOCK_MAX_OPEN_REQUESTS 50
58
59/* request queue sizes */
60#define I2O_BLOCK_REQ_MEMPOOL_SIZE		32
61
62#define KERNEL_SECTOR_SHIFT 9
63#define KERNEL_SECTOR_SIZE (1 << KERNEL_SECTOR_SHIFT)
64
65/* I2O Block OSM mempool struct */
66struct i2o_block_mempool {
67	struct kmem_cache *slab;
68	mempool_t *pool;
69};
70
71/* I2O Block device descriptor */
72struct i2o_block_device {
73	struct i2o_device *i2o_dev;	/* pointer to I2O device */
74	struct gendisk *gd;
75	spinlock_t lock;	/* queue lock */
76	struct list_head open_queue;	/* list of transferred, but unfinished
77					   requests */
78	unsigned int open_queue_depth;	/* number of requests in the queue */
79
80	int rcache;		/* read cache flags */
81	int wcache;		/* write cache flags */
82	int flags;
83	u16 power;		/* power state */
84	int media_change_flag;	/* media changed flag */
85};
86
87/* I2O Block device request */
88struct i2o_block_request {
89	struct list_head queue;
90	struct request *req;	/* corresponding request */
91	struct i2o_block_device *i2o_blk_dev;	/* I2O block device */
92	struct device *dev;	/* device used for DMA */
93	int sg_nents;		/* number of SG elements */
94	struct scatterlist sg_table[I2O_MAX_PHYS_SEGMENTS];	/* SG table */
95};
96
97/* I2O Block device delayed request */
98struct i2o_block_delayed_request {
99	struct delayed_work work;
100	struct request_queue *queue;
101};
102
103#endif
104