Commit 55db6c1b authored by Boaz Harrosh's avatar Boaz Harrosh Committed by James Bottomley
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[SCSI] scsi_error: code cleanup before refactoring of scsi_send_eh_cmnd() 



  - regrouped variables for easier reviewing of next patch
  - Support of cmnd==NULL in call to scsi_send_eh_cmnd()
  - In the @sense_bytes case set transfer size to the minimum
    size of sense_buffer and passed @sense_bytes. cmnd[4] is
    set accordingly.
  - REQUEST_SENSE is set into cmnd[0] so if @sense_bytes is
    not Zero passed @cmnd should be NULL.
  - Also save/restore resid of failed command.
  - Adjust caller

Signed-off-by: default avatarBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 2ca48230

drivers/scsi/scsi_error.c

+39 −32
Original line number Diff line number Diff line
@@ -592,36 +592,39 @@ static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd) 
/**

 * scsi_send_eh_cmnd  - submit a scsi command as part of error recory

 * @scmd:       SCSI command structure to hijack

 * @cmnd:       CDB to send

 * @cmnd:       CDB to send. Can be NULL if no new cmnd is needed

 * @cmnd_size:  size in bytes of @cmnd

 * @timeout:    timeout for this request

 * @copy_sense: request sense data if set to 1

 * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored)

 *

 * This function is used to send a scsi command down to a target device

 * as part of the error recovery process.  If @copy_sense is 0 the command

 * sent must be one that does not transfer any data.  If @copy_sense is 1

 * the command must be REQUEST_SENSE and this functions copies out the

 * sense buffer it got into @scmd->sense_buffer.

 * as part of the error recovery process.  If @sense_bytes is 0 the command

 * sent must be one that does not transfer any data.  If @sense_bytes != 0

 * @cmnd is ignored and this functions sets up a REQUEST_SENSE command

 * and cmnd buffers to read @sense_bytes into @scmd->sense_buffer.

 *

 * Return value:

 *    SUCCESS or FAILED or NEEDS_RETRY

 **/

static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd,

			     int cmnd_size, int timeout, int copy_sense)

			     int cmnd_size, int timeout, unsigned sense_bytes)

{

	struct scsi_device *sdev = scmd->device;

	struct Scsi_Host *shost = sdev->host;

	int old_result = scmd->result;

	DECLARE_COMPLETION_ONSTACK(done);

	unsigned long timeleft;

	unsigned long flags;

	struct scatterlist sgl;



	unsigned char old_cmd_len;

	unsigned char old_cmnd[MAX_COMMAND_SIZE];

	enum dma_data_direction old_data_direction;

	unsigned short old_use_sg;

	unsigned char old_cmd_len;

	unsigned old_bufflen;

	void *old_buffer;

	unsigned short old_use_sg;

	int old_resid;

	int old_result;



	struct scatterlist sgl;

	int rtn;



	/*
@@ -631,35 +634,41 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, 
	 * we will need to restore these values prior to running the actual

	 * command.

	 */

	old_buffer = scmd->request_buffer;

	old_bufflen = scmd->request_bufflen;

	old_cmd_len = scmd->cmd_len;

	memcpy(old_cmnd, scmd->cmnd, sizeof(scmd->cmnd));

	old_data_direction = scmd->sc_data_direction;

	old_cmd_len = scmd->cmd_len;

	old_bufflen = scmd->request_bufflen;

	old_buffer = scmd->request_buffer;

	old_use_sg = scmd->use_sg;

	old_resid = scmd->resid;

	old_result = scmd->result;



	memset(scmd->cmnd, 0, sizeof(scmd->cmnd));

	memcpy(scmd->cmnd, cmnd, cmnd_size);



	if (copy_sense) {

		sg_init_one(&sgl, scmd->sense_buffer,

			    sizeof(scmd->sense_buffer));



		scmd->sc_data_direction = DMA_FROM_DEVICE;

		scmd->request_bufflen = sgl.length;

	if (sense_bytes) {

		scmd->request_bufflen = min_t(unsigned,

		                       sizeof(scmd->sense_buffer), sense_bytes);

		sg_init_one(&sgl, scmd->sense_buffer, scmd->request_bufflen);

		scmd->request_buffer = &sgl;

		scmd->sc_data_direction = DMA_FROM_DEVICE;

		scmd->use_sg = 1;

		memset(scmd->cmnd, 0, sizeof(scmd->cmnd));

		scmd->cmnd[0] = REQUEST_SENSE;

		scmd->cmnd[4] = scmd->request_bufflen;

		scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);

	} else {

		scmd->request_buffer = NULL;

		scmd->request_bufflen = 0;

		scmd->sc_data_direction = DMA_NONE;

		scmd->use_sg = 0;

		if (cmnd) {

			memset(scmd->cmnd, 0, sizeof(scmd->cmnd));

			memcpy(scmd->cmnd, cmnd, cmnd_size);

			scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);

		}

	}



	scmd->underflow = 0;

	scmd->cmd_len = COMMAND_SIZE(scmd->cmnd[0]);



	if (sdev->scsi_level <= SCSI_2)

	if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN)

		scmd->cmnd[1] = (scmd->cmnd[1] & 0x1f) |

			(sdev->lun << 5 & 0xe0);
@@ -716,12 +725,13 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, 
	/*

	 * Restore original data

	 */

	scmd->request_buffer = old_buffer;

	scmd->request_bufflen = old_bufflen;

	scmd->cmd_len = old_cmd_len;

	memcpy(scmd->cmnd, old_cmnd, sizeof(scmd->cmnd));

	scmd->sc_data_direction = old_data_direction;

	scmd->cmd_len = old_cmd_len;

	scmd->request_bufflen = old_bufflen;

	scmd->request_buffer = old_buffer;

	scmd->use_sg = old_use_sg;

	scmd->resid = old_resid;

	scmd->result = old_result;

	return rtn;

}
@@ -737,10 +747,7 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, 
 **/

static int scsi_request_sense(struct scsi_cmnd *scmd)

{

	static unsigned char generic_sense[6] =

		{REQUEST_SENSE, 0, 0, 0, 252, 0};



	return scsi_send_eh_cmnd(scmd, generic_sense, 6, SENSE_TIMEOUT, 1);

	return scsi_send_eh_cmnd(scmd, NULL, 0, SENSE_TIMEOUT, ~0);

}



/**

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