confused about block device behaviour

[lord latex]

hi

i've got written a block device driver for the 2.4.x 
kernel and it seems to work. but something looks 
strange to me. i've go a very simple application that 
does nothing more then open the block device, read 
1024 byte and close the device. when i run this app. 
serveral times my do_request function gets called 
every time. why? i expect this block beeing buffered 
in the buffer cache. what do i don't see, or what is 
possibly wrong with my block device?

thanks