pktcdvd.h 5.87 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
/*
 * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
 * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
 *
 * May be copied or modified under the terms of the GNU General Public
 * License.  See linux/COPYING for more information.
 *
 * Packet writing layer for ATAPI and SCSI CD-R, CD-RW, DVD-R, and
 * DVD-RW devices.
 *
 */
#ifndef __PKTCDVD_H
#define __PKTCDVD_H

#include <linux/blkdev.h>
#include <linux/completion.h>
#include <linux/cdrom.h>
18 19
#include <linux/kobject.h>
#include <linux/sysfs.h>
20
#include <linux/mempool.h>
21
#include <uapi/linux/pktcdvd.h>
22 23 24 25 26 27

/* default bio write queue congestion marks */
#define PKT_WRITE_CONGESTION_ON    10000
#define PKT_WRITE_CONGESTION_OFF   9000


Linus Torvalds's avatar
Linus Torvalds committed
28 29
struct packet_settings
{
30
	__u32			size;		/* packet size in (512 byte) sectors */
Linus Torvalds's avatar
Linus Torvalds committed
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70
	__u8			fp;		/* fixed packets */
	__u8			link_loss;	/* the rest is specified
						 * as per Mt Fuji */
	__u8			write_type;
	__u8			track_mode;
	__u8			block_mode;
};

/*
 * Very crude stats for now
 */
struct packet_stats
{
	unsigned long		pkt_started;
	unsigned long		pkt_ended;
	unsigned long		secs_w;
	unsigned long		secs_rg;
	unsigned long		secs_r;
};

struct packet_cdrw
{
	struct list_head	pkt_free_list;
	struct list_head	pkt_active_list;
	spinlock_t		active_list_lock; /* Serialize access to pkt_active_list */
	struct task_struct	*thread;
	atomic_t		pending_bios;
};

/*
 * Switch to high speed reading after reading this many kilobytes
 * with no interspersed writes.
 */
#define HI_SPEED_SWITCH 512

struct packet_iosched
{
	atomic_t		attention;	/* Set to non-zero when queue processing is needed */
	int			writing;	/* Non-zero when writing, zero when reading */
	spinlock_t		lock;		/* Protecting read/write queue manipulations */
71 72
	struct bio_list		read_queue;
	struct bio_list		write_queue;
73
	sector_t		last_write;	/* The sector where the last write ended */
Linus Torvalds's avatar
Linus Torvalds committed
74 75 76 77 78 79
	int			successive_reads;
};

/*
 * 32 buffers of 2048 bytes
 */
80 81 82
#if (PAGE_SIZE % CD_FRAMESIZE) != 0
#error "PAGE_SIZE must be a multiple of CD_FRAMESIZE"
#endif
83
#define PACKET_MAX_SIZE		128
84
#define FRAMES_PER_PAGE		(PAGE_SIZE / CD_FRAMESIZE)
Linus Torvalds's avatar
Linus Torvalds committed
85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111
#define PACKET_MAX_SECTORS	(PACKET_MAX_SIZE * CD_FRAMESIZE >> 9)

enum packet_data_state {
	PACKET_IDLE_STATE,			/* Not used at the moment */
	PACKET_WAITING_STATE,			/* Waiting for more bios to arrive, so */
						/* we don't have to do as much */
						/* data gathering */
	PACKET_READ_WAIT_STATE,			/* Waiting for reads to fill in holes */
	PACKET_WRITE_WAIT_STATE,		/* Waiting for the write to complete */
	PACKET_RECOVERY_STATE,			/* Recover after read/write errors */
	PACKET_FINISHED_STATE,			/* After write has finished */

	PACKET_NUM_STATES			/* Number of possible states */
};

/*
 * Information needed for writing a single packet
 */
struct pktcdvd_device;

struct packet_data
{
	struct list_head	list;

	spinlock_t		lock;		/* Lock protecting state transitions and */
						/* orig_bios list */

112 113
	struct bio_list		orig_bios;	/* Original bios passed to pkt_make_request */
						/* that will be handled by this packet */
Linus Torvalds's avatar
Linus Torvalds committed
114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132
	int			write_size;	/* Total size of all bios in the orig_bios */
						/* list, measured in number of frames */

	struct bio		*w_bio;		/* The bio we will send to the real CD */
						/* device once we have all data for the */
						/* packet we are going to write */
	sector_t		sector;		/* First sector in this packet */
	int			frames;		/* Number of frames in this packet */

	enum packet_data_state	state;		/* Current state */
	atomic_t		run_sm;		/* Incremented whenever the state */
						/* machine needs to be run */
	long			sleep_time;	/* Set this to non-zero to make the state */
						/* machine run after this many jiffies. */

	atomic_t		io_wait;	/* Number of pending IO operations */
	atomic_t		io_errors;	/* Number of read/write errors during IO */

	struct bio		*r_bios[PACKET_MAX_SIZE]; /* bios to use during data gathering */
133
	struct page		*pages[PACKET_MAX_SIZE / FRAMES_PER_PAGE];
Linus Torvalds's avatar
Linus Torvalds committed
134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154

	int			cache_valid;	/* If non-zero, the data for the zone defined */
						/* by the sector variable is completely cached */
						/* in the pages[] vector. */

	int			id;		/* ID number for debugging */
	struct pktcdvd_device	*pd;
};

struct pkt_rb_node {
	struct rb_node		rb_node;
	struct bio		*bio;
};

struct packet_stacked_data
{
	struct bio		*bio;		/* Original read request bio */
	struct pktcdvd_device	*pd;
};
#define PSD_POOL_SIZE		64

155 156 157 158 159 160 161 162
struct pktcdvd_kobj
{
	struct kobject		kobj;
	struct pktcdvd_device	*pd;
};
#define to_pktcdvdkobj(_k) \
  ((struct pktcdvd_kobj*)container_of(_k,struct pktcdvd_kobj,kobj))

Linus Torvalds's avatar
Linus Torvalds committed
163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192
struct pktcdvd_device
{
	struct block_device	*bdev;		/* dev attached */
	dev_t			pkt_dev;	/* our dev */
	char			name[20];
	struct packet_settings	settings;
	struct packet_stats	stats;
	int			refcnt;		/* Open count */
	int			write_speed;	/* current write speed, kB/s */
	int			read_speed;	/* current read speed, kB/s */
	unsigned long		offset;		/* start offset */
	__u8			mode_offset;	/* 0 / 8 */
	__u8			type;
	unsigned long		flags;
	__u16			mmc3_profile;
	__u32			nwa;		/* next writable address */
	__u32			lra;		/* last recorded address */
	struct packet_cdrw	cdrw;
	wait_queue_head_t	wqueue;

	spinlock_t		lock;		/* Serialize access to bio_queue */
	struct rb_root		bio_queue;	/* Work queue of bios we need to handle */
	int			bio_queue_size;	/* Number of nodes in bio_queue */
	sector_t		current_sector;	/* Keep track of where the elevator is */
	atomic_t		scan_queue;	/* Set to non-zero when pkt_handle_queue */
						/* needs to be run. */
	mempool_t		*rb_pool;	/* mempool for pkt_rb_node allocations */

	struct packet_iosched   iosched;
	struct gendisk		*disk;
193 194 195

	int			write_congestion_off;
	int			write_congestion_on;
196

197
	struct device		*dev;		/* sysfs pktcdvd[0-7] dev */
198 199 200 201 202
	struct pktcdvd_kobj	*kobj_stat;	/* sysfs pktcdvd[0-7]/stat/     */
	struct pktcdvd_kobj	*kobj_wqueue;	/* sysfs pktcdvd[0-7]/write_queue/ */

	struct dentry		*dfs_d_root;	/* debugfs: devname directory */
	struct dentry		*dfs_f_info;	/* debugfs: info file */
Linus Torvalds's avatar
Linus Torvalds committed
203 204 205
};

#endif /* __PKTCDVD_H */