diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/scsi/scsi_mid_low_api.txt | 59 |
1 files changed, 31 insertions, 28 deletions
diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt index 570ef2b3d79b..df322c103466 100644 --- a/Documentation/scsi/scsi_mid_low_api.txt +++ b/Documentation/scsi/scsi_mid_low_api.txt @@ -1044,9 +1044,9 @@ Details: /** - * queuecommand - queue scsi command, invoke 'done' on completion + * queuecommand - queue scsi command, invoke scp->scsi_done on completion + * @shost: pointer to the scsi host object * @scp: pointer to scsi command object - * @done: function pointer to be invoked on completion * * Returns 0 on success. * @@ -1074,42 +1074,45 @@ Details: * * Other types of errors that are detected immediately may be * flagged by setting scp->result to an appropriate value, - * invoking the 'done' callback, and then returning 0 from this - * function. If the command is not performed immediately (and the - * LLD is starting (or will start) the given command) then this - * function should place 0 in scp->result and return 0. + * invoking the scp->scsi_done callback, and then returning 0 + * from this function. If the command is not performed + * immediately (and the LLD is starting (or will start) the given + * command) then this function should place 0 in scp->result and + * return 0. * * Command ownership. If the driver returns zero, it owns the - * command and must take responsibility for ensuring the 'done' - * callback is executed. Note: the driver may call done before - * returning zero, but after it has called done, it may not - * return any value other than zero. If the driver makes a - * non-zero return, it must not execute the command's done - * callback at any time. - * - * Locks: struct Scsi_Host::host_lock held on entry (with "irqsave") - * and is expected to be held on return. + * command and must take responsibility for ensuring the + * scp->scsi_done callback is executed. Note: the driver may + * call scp->scsi_done before returning zero, but after it has + * called scp->scsi_done, it may not return any value other than + * zero. If the driver makes a non-zero return, it must not + * execute the command's scsi_done callback at any time. + * + * Locks: up to and including 2.6.36, struct Scsi_Host::host_lock + * held on entry (with "irqsave") and is expected to be + * held on return. From 2.6.37 onwards, queuecommand is + * called without any locks held. * * Calling context: in interrupt (soft irq) or process context * - * Notes: This function should be relatively fast. Normally it will - * not wait for IO to complete. Hence the 'done' callback is invoked - * (often directly from an interrupt service routine) some time after - * this function has returned. In some cases (e.g. pseudo adapter - * drivers that manufacture the response to a SCSI INQUIRY) - * the 'done' callback may be invoked before this function returns. - * If the 'done' callback is not invoked within a certain period - * the SCSI mid level will commence error processing. - * If a status of CHECK CONDITION is placed in "result" when the - * 'done' callback is invoked, then the LLD driver should - * perform autosense and fill in the struct scsi_cmnd::sense_buffer + * Notes: This function should be relatively fast. Normally it + * will not wait for IO to complete. Hence the scp->scsi_done + * callback is invoked (often directly from an interrupt service + * routine) some time after this function has returned. In some + * cases (e.g. pseudo adapter drivers that manufacture the + * response to a SCSI INQUIRY) the scp->scsi_done callback may be + * invoked before this function returns. If the scp->scsi_done + * callback is not invoked within a certain period the SCSI mid + * level will commence error processing. If a status of CHECK + * CONDITION is placed in "result" when the scp->scsi_done + * callback is invoked, then the LLD driver should perform + * autosense and fill in the struct scsi_cmnd::sense_buffer * array. The scsi_cmnd::sense_buffer array is zeroed prior to * the mid level queuing a command to an LLD. * * Defined in: LLD **/ - int queuecommand(struct scsi_cmnd * scp, - void (*done)(struct scsi_cmnd *)) + int queuecommand(struct Scsi_Host *shost, struct scsi_cmnd * scp) /** |