From 28832e83379afd0b0e83b78ac317290c79ebd496 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 8 Mar 2006 11:19:51 +0100 Subject: [PATCH] update max_sectors documentation The max_sectors has been split into max_hw_sectors and max_sectors for some time. A patch to have blk_queue_max_sectors enforce this was sent by me and it broke IDE. This patch updates the documentation. Signed-off-by: Jens Axboe --- Documentation/block/biodoc.txt | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'Documentation/block') diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt index 8e63831971d5..f989a9e839b4 100644 --- a/Documentation/block/biodoc.txt +++ b/Documentation/block/biodoc.txt @@ -132,8 +132,18 @@ Some new queue property settings: limit. No highmem default. blk_queue_max_sectors(q, max_sectors) - Maximum size request you can handle in units of 512 byte - sectors. 255 default. + Sets two variables that limit the size of the request. + + - The request queue's max_sectors, which is a soft size in + in units of 512 byte sectors, and could be dynamically varied + by the core kernel. + + - The request queue's max_hw_sectors, which is a hard limit + and reflects the maximum size request a driver can handle + in units of 512 byte sectors. + + The default for both max_sectors and max_hw_sectors is + 255. The upper limit of max_sectors is 1024. blk_queue_max_phys_segments(q, max_segments) Maximum physical segments you can handle in a request. 128 -- cgit v1.2.3