diff options
Diffstat (limited to 'Documentation/scsi/scsi_mid_low_api.txt')
| -rw-r--r-- | Documentation/scsi/scsi_mid_low_api.txt | 66 |
1 files changed, 13 insertions, 53 deletions
diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt index d6a9bdeee7f2..731bc4f4c5e6 100644 --- a/Documentation/scsi/scsi_mid_low_api.txt +++ b/Documentation/scsi/scsi_mid_low_api.txt @@ -149,7 +149,7 @@ scsi_add_host() ----> scsi_scan_host() -------+ | slave_alloc() - slave_configure() --> scsi_adjust_queue_depth() + slave_configure() --> scsi_change_queue_depth() | slave_alloc() slave_configure() @@ -159,7 +159,7 @@ scsi_scan_host() -------+ ------------------------------------------------------------ If the LLD wants to adjust the default queue settings, it can invoke -scsi_adjust_queue_depth() in its slave_configure() routine. +scsi_change_queue_depth() in its slave_configure() routine. *** For scsi devices that the mid level tries to scan but do not respond, a slave_alloc(), slave_destroy() pair is called. @@ -203,7 +203,7 @@ LLD mid level LLD scsi_add_device() ------+ | slave_alloc() - slave_configure() [--> scsi_adjust_queue_depth()] + slave_configure() [--> scsi_change_queue_depth()] ------------------------------------------------------------ In a similar fashion, an LLD may become aware that a SCSI device has been @@ -261,7 +261,7 @@ init_this_scsi_driver() ----+ | scsi_register() | slave_alloc() - slave_configure() --> scsi_adjust_queue_depth() + slave_configure() --> scsi_change_queue_depth() slave_alloc() *** slave_destroy() *** | @@ -271,9 +271,9 @@ init_this_scsi_driver() ----+ slave_destroy() *** ------------------------------------------------------------ -The mid level invokes scsi_adjust_queue_depth() with tagged queuing off and -"cmd_per_lun" for that host as the queue length. These settings can be -overridden by a slave_configure() supplied by the LLD. +The mid level invokes scsi_change_queue_depth() with "cmd_per_lun" for that +host as the queue length. These settings can be overridden by a +slave_configure() supplied by the LLD. *** For scsi devices that the mid level tries to scan but do not respond, a slave_alloc(), slave_destroy() pair is called. @@ -366,13 +366,11 @@ is initialized. The functions below are listed alphabetically and their names all start with "scsi_". Summary: - scsi_activate_tcq - turn on tag command queueing scsi_add_device - creates new scsi device (lu) instance scsi_add_host - perform sysfs registration and set up transport class - scsi_adjust_queue_depth - change the queue depth on a SCSI device + scsi_change_queue_depth - change the queue depth on a SCSI device scsi_bios_ptable - return copy of block device's partition table scsi_block_requests - prevent further commands being queued to given host - scsi_deactivate_tcq - turn off tag command queueing scsi_host_alloc - return a new scsi_host instance whose refcount==1 scsi_host_get - increments Scsi_Host instance's refcount scsi_host_put - decrements Scsi_Host instance's refcount (free if 0) @@ -390,24 +388,6 @@ Summary: Details: /** - * scsi_activate_tcq - turn on tag command queueing ("ordered" task attribute) - * @sdev: device to turn on TCQ for - * @depth: queue depth - * - * Returns nothing - * - * Might block: no - * - * Notes: Eventually, it is hoped depth would be the maximum depth - * the device could cope with and the real queue depth - * would be adjustable from 0 to depth. - * - * Defined (inline) in: include/scsi/scsi_tcq.h - **/ -void scsi_activate_tcq(struct scsi_device *sdev, int depth) - - -/** * scsi_add_device - creates new scsi device (lu) instance * @shost: pointer to scsi host instance * @channel: channel number (rarely other than 0) @@ -456,11 +436,8 @@ int scsi_add_host(struct Scsi_Host *shost, struct device * dev) /** - * scsi_adjust_queue_depth - allow LLD to change queue depth on a SCSI device + * scsi_change_queue_depth - allow LLD to change queue depth on a SCSI device * @sdev: pointer to SCSI device to change queue depth on - * @tagged: 0 - no tagged queuing - * MSG_SIMPLE_TAG - simple tagged queuing - * MSG_ORDERED_TAG - ordered tagged queuing * @tags Number of tags allowed if tagged queuing enabled, * or number of commands the LLD can queue up * in non-tagged mode (as per cmd_per_lun). @@ -471,15 +448,12 @@ int scsi_add_host(struct Scsi_Host *shost, struct device * dev) * * Notes: Can be invoked any time on a SCSI device controlled by this * LLD. [Specifically during and after slave_configure() and prior to - * slave_destroy().] Can safely be invoked from interrupt code. Actual - * queue depth change may be delayed until the next command is being - * processed. See also scsi_activate_tcq() and scsi_deactivate_tcq(). + * slave_destroy().] Can safely be invoked from interrupt code. * * Defined in: drivers/scsi/scsi.c [see source code for more notes] * **/ -void scsi_adjust_queue_depth(struct scsi_device * sdev, int tagged, - int tags) +int scsi_change_queue_depth(struct scsi_device *sdev, int tags) /** @@ -515,20 +489,6 @@ void scsi_block_requests(struct Scsi_Host * shost) /** - * scsi_deactivate_tcq - turn off tag command queueing - * @sdev: device to turn off TCQ for - * @depth: queue depth (stored in sdev) - * - * Returns nothing - * - * Might block: no - * - * Defined (inline) in: include/scsi/scsi_tcq.h - **/ -void scsi_deactivate_tcq(struct scsi_device *sdev, int depth) - - -/** * scsi_host_alloc - create a scsi host adapter instance and perform basic * initialization. * @sht: pointer to scsi host template @@ -1254,7 +1214,7 @@ of interest: for disk firmware uploads. cmd_per_lun - maximum number of commands that can be queued on devices controlled by the host. Overridden by LLD calls to - scsi_adjust_queue_depth(). + scsi_change_queue_depth(). unchecked_isa_dma - 1=>only use bottom 16 MB of ram (ISA DMA addressing restriction), 0=>can use full 32 bit (or better) DMA address space @@ -1294,7 +1254,7 @@ struct scsi_cmnd Instances of this structure convey SCSI commands to the LLD and responses back to the mid level. The SCSI mid level will ensure that no more SCSI commands become queued against the LLD than are indicated by -scsi_adjust_queue_depth() (or struct Scsi_Host::cmd_per_lun). There will +scsi_change_queue_depth() (or struct Scsi_Host::cmd_per_lun). There will be at least one instance of struct scsi_cmnd available for each SCSI device. Members of interest: cmnd - array containing SCSI command |