include/scsi/scsi_request.h

   1 #ifndef _SCSI_SCSI_REQUEST_H
   2 #define _SCSI_SCSI_REQUEST_H
   3
   4 #include <scsi/scsi_cmnd.h>
   5
   6 struct request;
   7 struct scsi_cmnd;
   8 struct scsi_device;
   9 struct Scsi_Host;
  10
  11
  12 /*
  13  * This is essentially a slimmed down version of Scsi_Cmnd.  The point of
  14  * having this is that requests that are injected into the queue as result
  15  * of things like ioctls and character devices shouldn't be using a
  16  * Scsi_Cmnd until such a time that the command is actually at the head
  17  * of the queue and being sent to the driver.
  18  */
  19 struct scsi_request {
  20         int     sr_magic;
  21         int     sr_result;      /* Status code from lower level driver */
  22         unsigned char sr_sense_buffer[SCSI_SENSE_BUFFERSIZE];           /* obtained by REQUEST SENSE
  23                                                  * when CHECK CONDITION is
  24                                                  * received on original command
  25                                                  * (auto-sense) */
  26
  27         struct Scsi_Host *sr_host;
  28         struct scsi_device *sr_device;
  29         struct scsi_cmnd *sr_command;
  30         struct request *sr_request;     /* A copy of the command we are
  31                                    working on */
  32         unsigned sr_bufflen;    /* Size of data buffer */
  33         void *sr_buffer;                /* Data buffer */
  34         int sr_allowed;
  35         enum dma_data_direction sr_data_direction;
  36         unsigned char sr_cmd_len;
  37         unsigned char sr_cmnd[MAX_COMMAND_SIZE];
  38         void (*sr_done) (struct scsi_cmnd *);   /* Mid-level done function */
  39         int sr_timeout_per_command;
  40         unsigned short sr_use_sg;       /* Number of pieces of scatter-gather */
  41         unsigned short sr_sglist_len;   /* size of malloc'd scatter-gather list */
  42         unsigned sr_underflow;  /* Return error if less than
  43                                    this amount is transferred */
  44         void *upper_private_data;       /* reserved for owner (usually upper
  45                                            level driver) of this request */
  46 };
  47
  48 extern struct scsi_request *scsi_allocate_request(struct scsi_device *, gfp_t);
  49 extern void scsi_release_request(struct scsi_request *);
  50 extern void scsi_do_req(struct scsi_request *, const void *cmnd,
  51                         void *buffer, unsigned bufflen,
  52                         void (*done) (struct scsi_cmnd *),
  53                         int timeout, int retries);
  54 #endif /* _SCSI_SCSI_REQUEST_H */