re-using buffer_head

Badrinath Venkatachari (badri@cs.wpi.edu)
Thu, 27 Apr 2000 16:12:15 -0400 (EDT)


hi,
When make_request() is called from ll_rw_block() for disk I/O, it first
finds out if the buffer_head is uptodate. If the buffer_head is uptodate,
then it returns...

What I want to do is to make make_request() return if the buffer_head
passed to it is NOT uptodate and have a piece of code inside ll_rw_block()
which checks for the return without being satisfied from the cache and
blocks for sometime before calling make_request() again but this time to
get the data from the disk instead. To do this, is it legal if i use the
same buffer_head that i had when I tried the first time...Are there any
issues that i have to be careful about like the buffer_head being given to
another process ???

(Assume that i have extended the buffer_head to include information that
would force make_request() to let it go through the second time to get
data from the disk without simply returning as in the first instance).

TIA

badri

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/