[PATCH] USB Storage: remove dependency on SCSI-provided serial/tag number

This patch started life as as531 from Alan Stern.  It has been rediffed
against the latest tree.

The SCSI people have deprecated the use of scsi_cmnd.serial_number for
anything other than printk.  Worse than that, the SCSI core doesn't
always increment the number (when the error handler is running, for
example).  So this patch creates a locally-stored value for use in
bulk-only tags.  The net result is a simplification, since we no longer
have to save & restore the serial_number value while autosensing.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Matthew Dharm 2005-07-28 14:43:08 -07:00 committed by Greg Kroah-Hartman
parent 9a57116bc9
commit 0f64e07813
2 changed files with 3 additions and 8 deletions

View File

@ -611,7 +611,6 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
unsigned char old_sc_data_direction;
unsigned char old_cmd_len;
unsigned char old_cmnd[MAX_COMMAND_SIZE];
unsigned long old_serial_number;
int old_resid;
US_DEBUGP("Issuing auto-REQUEST_SENSE\n");
@ -648,10 +647,6 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
old_sg = srb->use_sg;
srb->use_sg = 0;
/* change the serial number -- toggle the high bit*/
old_serial_number = srb->serial_number;
srb->serial_number ^= 0x80000000;
/* issue the auto-sense command */
old_resid = srb->resid;
srb->resid = 0;
@ -662,7 +657,6 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
srb->request_buffer = old_request_buffer;
srb->request_bufflen = old_request_bufflen;
srb->use_sg = old_sg;
srb->serial_number = old_serial_number;
srb->sc_data_direction = old_sc_data_direction;
srb->cmd_len = old_cmd_len;
memcpy(srb->cmnd, old_cmnd, MAX_COMMAND_SIZE);
@ -985,7 +979,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
bcb->DataTransferLength = cpu_to_le32(transfer_length);
bcb->Flags = srb->sc_data_direction == DMA_FROM_DEVICE ? 1 << 7 : 0;
bcb->Tag = srb->serial_number;
bcb->Tag = ++us->tag;
bcb->Lun = srb->device->lun;
if (us->flags & US_FL_SCM_MULT_TARG)
bcb->Lun |= srb->device->id << 4;
@ -1074,7 +1068,7 @@ int usb_stor_Bulk_transport(struct scsi_cmnd *srb, struct us_data *us)
US_DEBUGP("Bulk Status S 0x%x T 0x%x R %u Stat 0x%x\n",
le32_to_cpu(bcs->Signature), bcs->Tag,
residue, bcs->Status);
if (bcs->Tag != srb->serial_number || bcs->Status > US_BULK_STAT_PHASE) {
if (bcs->Tag != us->tag || bcs->Status > US_BULK_STAT_PHASE) {
US_DEBUGP("Bulk logical error\n");
return USB_STOR_TRANSPORT_ERROR;
}

View File

@ -158,6 +158,7 @@ struct us_data {
/* SCSI interfaces */
struct scsi_cmnd *srb; /* current srb */
unsigned int tag; /* current dCBWTag */
/* thread information */
int pid; /* control thread */