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 | |
28 | struct 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 | */ |
42 | struct 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 | |
51 | struct 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 | |
66 | struct 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 | |
87 | enum 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 | */ |
103 | struct pktcdvd_device; |
104 | |
105 | struct 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 | |
143 | struct pkt_rb_node { |
144 | struct rb_node rb_node; |
145 | struct bio *bio; |
146 | }; |
147 | |
148 | struct 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 | |
155 | struct pktcdvd_device |
156 | { |
157 | struct bdev_handle *bdev_handle; /* dev attached */ |
158 | /* handle acquired for bdev during pkt_open_dev() */ |
159 | struct bdev_handle *open_bdev_handle; |
160 | dev_t pkt_dev; /* our dev */ |
161 | struct packet_settings settings; |
162 | struct packet_stats stats; |
163 | int refcnt; /* Open count */ |
164 | int write_speed; /* current write speed, kB/s */ |
165 | int read_speed; /* current read speed, kB/s */ |
166 | unsigned long offset; /* start offset */ |
167 | __u8 mode_offset; /* 0 / 8 */ |
168 | __u8 type; |
169 | unsigned long flags; |
170 | __u16 mmc3_profile; |
171 | __u32 nwa; /* next writable address */ |
172 | __u32 lra; /* last recorded address */ |
173 | struct packet_cdrw cdrw; |
174 | wait_queue_head_t wqueue; |
175 | |
176 | spinlock_t lock; /* Serialize access to bio_queue */ |
177 | struct rb_root bio_queue; /* Work queue of bios we need to handle */ |
178 | int bio_queue_size; /* Number of nodes in bio_queue */ |
179 | bool congested; /* Someone is waiting for bio_queue_size |
180 | * to drop. */ |
181 | sector_t current_sector; /* Keep track of where the elevator is */ |
182 | atomic_t scan_queue; /* Set to non-zero when pkt_handle_queue */ |
183 | /* needs to be run. */ |
184 | mempool_t rb_pool; /* mempool for pkt_rb_node allocations */ |
185 | |
186 | struct packet_iosched iosched; |
187 | struct gendisk *disk; |
188 | |
189 | int write_congestion_off; |
190 | int write_congestion_on; |
191 | |
192 | struct device *dev; /* sysfs pktcdvd[0-7] dev */ |
193 | |
194 | struct dentry *dfs_d_root; /* debugfs: devname directory */ |
195 | struct dentry *dfs_f_info; /* debugfs: info file */ |
196 | }; |
197 | |
198 | #endif /* __PKTCDVD_H */ |
199 | |