pktcdvd.h (5777B)
1/* 2 * Copyright (C) 2000 Jens Axboe <axboe@suse.de> 3 * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com> 4 * 5 * May be copied or modified under the terms of the GNU General Public 6 * License. See linux/COPYING for more information. 7 * 8 * Packet writing layer for ATAPI and SCSI CD-R, CD-RW, DVD-R, and 9 * DVD-RW devices. 10 * 11 */ 12#ifndef __PKTCDVD_H 13#define __PKTCDVD_H 14 15#include <linux/blkdev.h> 16#include <linux/completion.h> 17#include <linux/cdrom.h> 18#include <linux/kobject.h> 19#include <linux/sysfs.h> 20#include <linux/mempool.h> 21#include <uapi/linux/pktcdvd.h> 22 23/* default bio write queue congestion marks */ 24#define PKT_WRITE_CONGESTION_ON 10000 25#define PKT_WRITE_CONGESTION_OFF 9000 26 27 28struct packet_settings 29{ 30 __u32 size; /* packet size in (512 byte) sectors */ 31 __u8 fp; /* fixed packets */ 32 __u8 link_loss; /* the rest is specified 33 * as per Mt Fuji */ 34 __u8 write_type; 35 __u8 track_mode; 36 __u8 block_mode; 37}; 38 39/* 40 * Very crude stats for now 41 */ 42struct packet_stats 43{ 44 unsigned long pkt_started; 45 unsigned long pkt_ended; 46 unsigned long secs_w; 47 unsigned long secs_rg; 48 unsigned long secs_r; 49}; 50 51struct packet_cdrw 52{ 53 struct list_head pkt_free_list; 54 struct list_head pkt_active_list; 55 spinlock_t active_list_lock; /* Serialize access to pkt_active_list */ 56 struct task_struct *thread; 57 atomic_t pending_bios; 58}; 59 60/* 61 * Switch to high speed reading after reading this many kilobytes 62 * with no interspersed writes. 63 */ 64#define HI_SPEED_SWITCH 512 65 66struct packet_iosched 67{ 68 atomic_t attention; /* Set to non-zero when queue processing is needed */ 69 int writing; /* Non-zero when writing, zero when reading */ 70 spinlock_t lock; /* Protecting read/write queue manipulations */ 71 struct bio_list read_queue; 72 struct bio_list write_queue; 73 sector_t last_write; /* The sector where the last write ended */ 74 int successive_reads; 75}; 76 77/* 78 * 32 buffers of 2048 bytes 79 */ 80#if (PAGE_SIZE % CD_FRAMESIZE) != 0 81#error "PAGE_SIZE must be a multiple of CD_FRAMESIZE" 82#endif 83#define PACKET_MAX_SIZE 128 84#define FRAMES_PER_PAGE (PAGE_SIZE / CD_FRAMESIZE) 85#define PACKET_MAX_SECTORS (PACKET_MAX_SIZE * CD_FRAMESIZE >> 9) 86 87enum packet_data_state { 88 PACKET_IDLE_STATE, /* Not used at the moment */ 89 PACKET_WAITING_STATE, /* Waiting for more bios to arrive, so */ 90 /* we don't have to do as much */ 91 /* data gathering */ 92 PACKET_READ_WAIT_STATE, /* Waiting for reads to fill in holes */ 93 PACKET_WRITE_WAIT_STATE, /* Waiting for the write to complete */ 94 PACKET_RECOVERY_STATE, /* Recover after read/write errors */ 95 PACKET_FINISHED_STATE, /* After write has finished */ 96 97 PACKET_NUM_STATES /* Number of possible states */ 98}; 99 100/* 101 * Information needed for writing a single packet 102 */ 103struct pktcdvd_device; 104 105struct packet_data 106{ 107 struct list_head list; 108 109 spinlock_t lock; /* Lock protecting state transitions and */ 110 /* orig_bios list */ 111 112 struct bio_list orig_bios; /* Original bios passed to pkt_make_request */ 113 /* that will be handled by this packet */ 114 int write_size; /* Total size of all bios in the orig_bios */ 115 /* list, measured in number of frames */ 116 117 struct bio *w_bio; /* The bio we will send to the real CD */ 118 /* device once we have all data for the */ 119 /* packet we are going to write */ 120 sector_t sector; /* First sector in this packet */ 121 int frames; /* Number of frames in this packet */ 122 123 enum packet_data_state state; /* Current state */ 124 atomic_t run_sm; /* Incremented whenever the state */ 125 /* machine needs to be run */ 126 long sleep_time; /* Set this to non-zero to make the state */ 127 /* machine run after this many jiffies. */ 128 129 atomic_t io_wait; /* Number of pending IO operations */ 130 atomic_t io_errors; /* Number of read/write errors during IO */ 131 132 struct bio *r_bios[PACKET_MAX_SIZE]; /* bios to use during data gathering */ 133 struct page *pages[PACKET_MAX_SIZE / FRAMES_PER_PAGE]; 134 135 int cache_valid; /* If non-zero, the data for the zone defined */ 136 /* by the sector variable is completely cached */ 137 /* in the pages[] vector. */ 138 139 int id; /* ID number for debugging */ 140 struct pktcdvd_device *pd; 141}; 142 143struct pkt_rb_node { 144 struct rb_node rb_node; 145 struct bio *bio; 146}; 147 148struct packet_stacked_data 149{ 150 struct bio *bio; /* Original read request bio */ 151 struct pktcdvd_device *pd; 152}; 153#define PSD_POOL_SIZE 64 154 155struct pktcdvd_device 156{ 157 struct block_device *bdev; /* dev attached */ 158 dev_t pkt_dev; /* our dev */ 159 char name[20]; 160 struct packet_settings settings; 161 struct packet_stats stats; 162 int refcnt; /* Open count */ 163 int write_speed; /* current write speed, kB/s */ 164 int read_speed; /* current read speed, kB/s */ 165 unsigned long offset; /* start offset */ 166 __u8 mode_offset; /* 0 / 8 */ 167 __u8 type; 168 unsigned long flags; 169 __u16 mmc3_profile; 170 __u32 nwa; /* next writable address */ 171 __u32 lra; /* last recorded address */ 172 struct packet_cdrw cdrw; 173 wait_queue_head_t wqueue; 174 175 spinlock_t lock; /* Serialize access to bio_queue */ 176 struct rb_root bio_queue; /* Work queue of bios we need to handle */ 177 int bio_queue_size; /* Number of nodes in bio_queue */ 178 bool congested; /* Someone is waiting for bio_queue_size 179 * to drop. */ 180 sector_t current_sector; /* Keep track of where the elevator is */ 181 atomic_t scan_queue; /* Set to non-zero when pkt_handle_queue */ 182 /* needs to be run. */ 183 mempool_t rb_pool; /* mempool for pkt_rb_node allocations */ 184 185 struct packet_iosched iosched; 186 struct gendisk *disk; 187 188 int write_congestion_off; 189 int write_congestion_on; 190 191 struct device *dev; /* sysfs pktcdvd[0-7] dev */ 192 193 struct dentry *dfs_d_root; /* debugfs: devname directory */ 194 struct dentry *dfs_f_info; /* debugfs: info file */ 195}; 196 197#endif /* __PKTCDVD_H */