From owner-freebsd-hackers Tue May 23 11: 2:27 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from arjun.niksun.com (gwnew.niksun.com [206.20.52.130]) by hub.freebsd.org (Postfix) with ESMTP id 661BB37B8C9 for ; Tue, 23 May 2000 11:02:21 -0700 (PDT) (envelope-from joy@niksun.com) Received: from falcon.niksun.com (falcon.niksun.com [10.0.0.167]) by arjun.niksun.com (8.9.3/8.9.3) with ESMTP id OAA58262 for ; Tue, 23 May 2000 14:02:16 -0400 (EDT) (envelope-from joy@falcon.niksun.com) Message-ID: <392AC7BF.C458DD75@falcon.niksun.com> Date: Tue, 23 May 2000 14:02:39 -0400 From: Joy Ganguly X-Mailer: Mozilla 4.51 [en] (X11; I; FreeBSD 3.2-RELEASE i386) X-Accept-Language: en MIME-Version: 1.0 To: freebsd-hackers Subject: disk buffer allocation?? Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG hi all, i am working on a project to do a zero copy tranfer from a netwrok buffer to a file. i need to know about buffer allocation in freeBSD. ive read the source but there are a few queries: i) what is meant by the B_MALLOC flag?? it seems if this flag is set the buffers memory is malloced and b_data point to the malloced area. but then where does b_kvabase point to ?? The buffers memory is allocated in allocbuf() but its kva is allocated in getnewbuf(). ii) what does the B_LOCKED and B_BUSY flags mean?? iii) Is setting the B_INVAL flag enough to invalidate the buffer?? thanx in advance joy To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message