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-rw-r--r--include/scsi/scsi_cmnd.h165
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 */