[PATCH] scsi_debug: simple short transfer injection

[PATCH] scsi_debug: simple short transfer injection

[Christoph Hellwig]

Add an option to only transfer half the data for every n-th command.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/scsi/scsi_debug.c |    8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 6de6b1a..5f64dc8 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -130,6 +130,7 @@ static const char * scsi_debug_version_date = "20100324";
 #define SCSI_DEBUG_OPT_DIF_ERR   32
 #define SCSI_DEBUG_OPT_DIX_ERR   64
 #define SCSI_DEBUG_OPT_MAC_TIMEOUT  128
+#define SCSI_DEBUG_OPT_SHORT_TRANSFER	256
 /* When "every_nth" > 0 then modulo "every_nth" commands:
  *   - a no response is simulated if SCSI_DEBUG_OPT_TIMEOUT is set
  *   - a RECOVERED_ERROR is simulated on successful read and write
@@ -3583,6 +3584,7 @@ int scsi_debug_queuecommand_lck(struct scsi_cmnd *SCpnt, done_funct_t done)
 	int inj_transport = 0;
 	int inj_dif = 0;
 	int inj_dix = 0;
+	int inj_short = 0;
 	int delay_override = 0;
 	int unmap = 0;
 
@@ -3628,6 +3630,8 @@ int scsi_debug_queuecommand_lck(struct scsi_cmnd *SCpnt, done_funct_t done)
 			inj_dif = 1; /* to reads and writes below */
 		else if (SCSI_DEBUG_OPT_DIX_ERR & scsi_debug_opts)
 			inj_dix = 1; /* to reads and writes below */
+		else if (SCSI_DEBUG_OPT_SHORT_TRANSFER & scsi_debug_opts)
+			inj_short = 1;
 	}
 
 	if (devip->wlun) {
@@ -3744,6 +3748,10 @@ read:
 		if (scsi_debug_fake_rw)
 			break;
 		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
+
+		if (inj_short)
+			num /= 2;
+
 		errsts = resp_read(SCpnt, lba, num, devip, ei_lba);
 		if (inj_recovered && (0 == errsts)) {
 			mk_sense_buffer(devip, RECOVERED_ERROR,
-- 
1.7.10.4

Re: [PATCH] scsi_debug: simple short transfer injection

[Douglas Gilbert]

On 14-04-28 11:58 AM, Christoph Hellwig wrote:
> Add an option to only transfer half the data for every n-th command.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Acked-by: Douglas Gilbert <dgilbert@interlog.com>

> ---
>   drivers/scsi/scsi_debug.c |    8 ++++++++
>   1 file changed, 8 insertions(+)
>
> diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
> index 6de6b1a..5f64dc8 100644
> --- a/drivers/scsi/scsi_debug.c
> +++ b/drivers/scsi/scsi_debug.c
> @@ -130,6 +130,7 @@ static const char * scsi_debug_version_date = "20100324";
>   #define SCSI_DEBUG_OPT_DIF_ERR   32
>   #define SCSI_DEBUG_OPT_DIX_ERR   64
>   #define SCSI_DEBUG_OPT_MAC_TIMEOUT  128
> +#define SCSI_DEBUG_OPT_SHORT_TRANSFER	256
>   /* When "every_nth" > 0 then modulo "every_nth" commands:
>    *   - a no response is simulated if SCSI_DEBUG_OPT_TIMEOUT is set
>    *   - a RECOVERED_ERROR is simulated on successful read and write
> @@ -3583,6 +3584,7 @@ int scsi_debug_queuecommand_lck(struct scsi_cmnd *SCpnt, done_funct_t done)
>   	int inj_transport = 0;
>   	int inj_dif = 0;
>   	int inj_dix = 0;
> +	int inj_short = 0;
>   	int delay_override = 0;
>   	int unmap = 0;
>
> @@ -3628,6 +3630,8 @@ int scsi_debug_queuecommand_lck(struct scsi_cmnd *SCpnt, done_funct_t done)
>   			inj_dif = 1; /* to reads and writes below */
>   		else if (SCSI_DEBUG_OPT_DIX_ERR & scsi_debug_opts)
>   			inj_dix = 1; /* to reads and writes below */
> +		else if (SCSI_DEBUG_OPT_SHORT_TRANSFER & scsi_debug_opts)
> +			inj_short = 1;
>   	}
>
>   	if (devip->wlun) {
> @@ -3744,6 +3748,10 @@ read:
>   		if (scsi_debug_fake_rw)
>   			break;
>   		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
> +
> +		if (inj_short)
> +			num /= 2;
> +
>   		errsts = resp_read(SCpnt, lba, num, devip, ei_lba);
>   		if (inj_recovered && (0 == errsts)) {
>   			mk_sense_buffer(devip, RECOVERED_ERROR,
>