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Diffstat (limited to 'include/scsi/scsi_cmnd.h')
| -rw-r--r-- | include/scsi/scsi_cmnd.h | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h new file mode 100644 index 00000000000..9d9871c28ab --- /dev/null +++ b/include/scsi/scsi_cmnd.h @@ -0,0 +1,165 @@ +#ifndef _SCSI_SCSI_CMND_H +#define _SCSI_SCSI_CMND_H + +#include <linux/dma-mapping.h> +#include <linux/list.h> +#include <linux/types.h> + +struct request; +struct scatterlist; +struct scsi_device; +struct scsi_request; + + +/* embedded in scsi_cmnd */ +struct scsi_pointer { + char *ptr; /* data pointer */ + int this_residual; /* left in this buffer */ + struct scatterlist *buffer; /* which buffer */ + int buffers_residual; /* how many buffers left */ + + dma_addr_t dma_handle; + + volatile int Status; + volatile int Message; + volatile int have_data_in; + volatile int sent_command; + volatile int phase; +}; + +struct scsi_cmnd { + int sc_magic; + + struct scsi_device *device; + unsigned short state; + unsigned short owner; + struct scsi_request *sc_request; + + struct list_head list; /* scsi_cmnd participates in queue lists */ + + struct list_head eh_entry; /* entry for the host eh_cmd_q */ + int eh_state; /* Used for state tracking in error handlr */ + int eh_eflags; /* Used by error handlr */ + void (*done) (struct scsi_cmnd *); /* Mid-level done function */ + + /* + * A SCSI Command is assigned a nonzero serial_number when internal_cmnd + * passes it to the driver's queue command function. The serial_number + * is cleared when scsi_done is entered indicating that the command has + * been completed. If a timeout occurs, the serial number at the moment + * of timeout is copied into serial_number_at_timeout. By subsequently + * comparing the serial_number and serial_number_at_timeout fields + * during abort or reset processing, we can detect whether the command + * has already completed. This also detects cases where the command has + * completed and the SCSI Command structure has already being reused + * for another command, so that we can avoid incorrectly aborting or + * resetting the new command. + * The serial number is only unique per host. + */ + unsigned long serial_number; + unsigned long serial_number_at_timeout; + + int retries; + int allowed; + int timeout_per_command; + int timeout_total; + int timeout; + + /* + * We handle the timeout differently if it happens when a reset, + * abort, etc are in process. + */ + unsigned volatile char internal_timeout; + + unsigned char cmd_len; + unsigned char old_cmd_len; + enum dma_data_direction sc_data_direction; + enum dma_data_direction sc_old_data_direction; + + /* These elements define the operation we are about to perform */ +#define MAX_COMMAND_SIZE 16 + unsigned char cmnd[MAX_COMMAND_SIZE]; + unsigned request_bufflen; /* Actual request size */ + + struct timer_list eh_timeout; /* Used to time out the command. */ + void *request_buffer; /* Actual requested buffer */ + + /* These elements define the operation we ultimately want to perform */ + unsigned char data_cmnd[MAX_COMMAND_SIZE]; + unsigned short old_use_sg; /* We save use_sg here when requesting + * sense info */ + unsigned short use_sg; /* Number of pieces of scatter-gather */ + unsigned short sglist_len; /* size of malloc'd scatter-gather list */ + unsigned short abort_reason; /* If the mid-level code requests an + * abort, this is the reason. */ + unsigned bufflen; /* Size of data buffer */ + void *buffer; /* Data buffer */ + + unsigned underflow; /* Return error if less than + this amount is transferred */ + unsigned old_underflow; /* save underflow here when reusing the + * command for error handling */ + + unsigned transfersize; /* How much we are guaranteed to + transfer with each SCSI transfer + (ie, between disconnect / + reconnects. Probably == sector + size */ + + int resid; /* Number of bytes requested to be + transferred less actual number + transferred (0 if not supported) */ + + struct request *request; /* The command we are + working on */ + +#define SCSI_SENSE_BUFFERSIZE 96 + unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE]; /* obtained by REQUEST SENSE + * when CHECK CONDITION is + * received on original command + * (auto-sense) */ + + /* Low-level done function - can be used by low-level driver to point + * to completion function. Not used by mid/upper level code. */ + void (*scsi_done) (struct scsi_cmnd *); + + /* + * The following fields can be written to by the host specific code. + * Everything else should be left alone. + */ + struct scsi_pointer SCp; /* Scratchpad used by some host adapters */ + + unsigned char *host_scribble; /* The host adapter is allowed to + * call scsi_malloc and get some memory + * and hang it here. The host adapter + * is also expected to call scsi_free + * to release this memory. (The memory + * obtained by scsi_malloc is guaranteed + * to be at an address < 16Mb). */ + + int result; /* Status code from lower level driver */ + + unsigned char tag; /* SCSI-II queued command tag */ + unsigned long pid; /* Process ID, starts at 0. Unique per host. */ +}; + +/* + * These are the values that scsi_cmd->state can take. + */ +#define SCSI_STATE_TIMEOUT 0x1000 +#define SCSI_STATE_FINISHED 0x1001 +#define SCSI_STATE_FAILED 0x1002 +#define SCSI_STATE_QUEUED 0x1003 +#define SCSI_STATE_UNUSED 0x1006 +#define SCSI_STATE_DISCONNECTING 0x1008 +#define SCSI_STATE_INITIALIZING 0x1009 +#define SCSI_STATE_BHQUEUE 0x100a +#define SCSI_STATE_MLQUEUE 0x100b + + +extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, int); +extern void scsi_put_command(struct scsi_cmnd *); +extern void scsi_io_completion(struct scsi_cmnd *, unsigned int, unsigned int); +extern void scsi_finish_command(struct scsi_cmnd *cmd); + +#endif /* _SCSI_SCSI_CMND_H */ |