root/include/linux/blkdev.h

/* */

INCLUDED FROM

   1 #ifndef _LINUX_BLKDEV_H
   2 #define _LINUX_BLKDEV_H
   3 
   4 #include <linux/major.h>
   5 #include <linux/sched.h>
   6 #include <linux/genhd.h>
   7 
   8 /*
   9  * Ok, this is an expanded form so that we can use the same
  10  * request for paging requests when that is implemented. In
  11  * paging, 'bh' is NULL, and the semaphore is used to wait
  12  * for read/write completion.
  13  */
  14 struct request {
  15         volatile int rq_status; /* should split this into a few status bits */
  16 #define RQ_INACTIVE             (-1)
  17 #define RQ_ACTIVE               1
  18 #define RQ_SCSI_BUSY            0xffff
  19 #define RQ_SCSI_DONE            0xfffe
  20 #define RQ_SCSI_DISCONNECTING   0xffe0
  21 
  22         kdev_t rq_dev;
  23         int cmd;                /* READ or WRITE */
  24         int errors;
  25         unsigned long sector;
  26         unsigned long nr_sectors;
  27         unsigned long current_nr_sectors;
  28         char * buffer;
  29         struct semaphore * sem;
  30         struct buffer_head * bh;
  31         struct buffer_head * bhtail;
  32         struct request * next;
  33 };
  34 
  35 struct blk_dev_struct {
  36         void (*request_fn)(void);
  37         struct request * current_request;
  38 };
  39 
  40 struct sec_size {
  41         unsigned block_size;
  42         unsigned block_size_bits;
  43 };
  44 
  45 extern struct sec_size * blk_sec[MAX_BLKDEV];
  46 extern struct blk_dev_struct blk_dev[MAX_BLKDEV];
  47 extern struct wait_queue * wait_for_request;
  48 extern void resetup_one_dev(struct gendisk *dev, int drive);
  49 
  50 extern int * blk_size[MAX_BLKDEV];
  51 
  52 extern int * blksize_size[MAX_BLKDEV];
  53 
  54 extern int * hardsect_size[MAX_BLKDEV];
  55 
  56 #endif

/* */