who decrements can_queue in Scsi_Host structure ?

[MEHTA,HIREN]

Hi LIsts,

In the hosts.h file, the following was the definition of
can_queue variable in the Scsi_Host_Template (SHT) structure. 

    /* 
     * THis determines if we will use a non-interrupt driven
     * or an interrupt driver scheme, It is set to the maximum number
     * of simultaneous commands a given host adapter will accept.
     */
    int can_queue;

Scsi_Host structure also has the same variable which gets initialized
with the can_queue of SHT structure in the scsi_register().
Let's say the can_queue in initialized to 16. Now, I could not find
anybody decrementing this variable. So, when the time comes to
send a new command to the hba, the can_queue of the host sturcture is
checked and if that is non-zero, then the queuecommand() entry point
is immediately called. So, the queuecommand will always be called 
even if the host is already given 'can_queue' commands.

Any inputs on this ?

-hiren