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/*
* 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>
#include <linux/kobject.h>
#include <linux/sysfs.h>
#include <linux/mempool.h>
#include <uapi/linux/pktcdvd.h>
/* default bio write queue congestion marks */
#define PKT_WRITE_CONGESTION_ON 10000
#define PKT_WRITE_CONGESTION_OFF 9000
struct packet_settings
{
__u32 size; /* packet size in (512 byte) sectors */
__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 */
struct bio_list read_queue;
struct bio_list write_queue;
sector_t last_write; /* The sector where the last write ended */
int successive_reads;
};
/*
* 32 buffers of 2048 bytes
*/
#if (PAGE_SIZE % CD_FRAMESIZE) != 0
#error "PAGE_SIZE must be a multiple of CD_FRAMESIZE"
#endif
#define PACKET_MAX_SIZE 128
#define FRAMES_PER_PAGE (PAGE_SIZE / CD_FRAMESIZE)
#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 */
struct bio_list orig_bios; /* Original bios passed to pkt_make_request */
/* that will be handled by this packet */
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 */
struct page *pages[PACKET_MAX_SIZE / FRAMES_PER_PAGE];
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
struct pktcdvd_device
{
struct bdev_handle *bdev_handle; /* dev attached */
/* handle acquired for bdev during pkt_open_dev() */
struct bdev_handle *open_bdev_handle;
dev_t pkt_dev; /* our dev */
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 */
bool congested; /* Someone is waiting for bio_queue_size
* to drop. */
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;
int write_congestion_off;
int write_congestion_on;
struct device *dev; /* sysfs pktcdvd[0-7] dev */
struct dentry *dfs_d_root; /* debugfs: devname directory */
struct dentry *dfs_f_info; /* debugfs: info file */
};
#endif /* __PKTCDVD_H */
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