From owner-freebsd-hackers@freebsd.org Sat May 26 13:38:22 2018 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 88844F763AA for ; Sat, 26 May 2018 13:38:22 +0000 (UTC) (envelope-from lakhanshiva@gmail.com) Received: from mail-ot0-x244.google.com (mail-ot0-x244.google.com [IPv6:2607:f8b0:4003:c0f::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id F1B1270092; Sat, 26 May 2018 13:38:21 +0000 (UTC) (envelope-from lakhanshiva@gmail.com) Received: by mail-ot0-x244.google.com with SMTP id 77-v6so9064547otd.4; Sat, 26 May 2018 06:38:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=bAlx7sz6cuMusvxuxYef0o/t5YmWMSHUmNXWOFjbfMY=; b=KucijM0xhdMwI2ASEbrWh41PeVDK1cYcA04Yt7C001VYC4TppSeLX9+BNUG6Z2fZ0x mFcqDtfMyTvARxLDorc9KgjQMKA2F3T2MHvIX9lSbvqBGVMEmrZx7OW7PcmiTZDplhJh lopCEQpOTy1GPXUNaTAsFP6Q6q083uN+dHD2mhLGAAdwa+TJwIVTN+qRxLJ+CUJ9TJwn UPUxFUlMGDvwhpYZT/H9H9Q9kMpO7jt4A76m8RgP5bdNZAsYb/UB3R6pnfHQJXN6vHI+ OfCKdyOSjtQhwKB/QL/zq29rgGw0f9SH9LMMlfOgOeyAWJ1Og4zD7EdBgXF0z/7EiYhJ aDDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=bAlx7sz6cuMusvxuxYef0o/t5YmWMSHUmNXWOFjbfMY=; b=Ek/05sycfmEZopWiHCUa5R2d3lWUabmfdcaVdj06K6YTDbiOm8H1lnEqKYvkmu7vfs 8yzzSP9BOyV6h48cTOrH+UqmFcTLyjaat8H2n8NEwXEEQJYtL/ohJpo8ZEVBcEXNMdyX ExYmGLrIU/IGu6YggUzR9KRQDTSV1b4S7N36rfy0RjTgNjdXNUamOWsQb0w7oL0Dx3FB NEZ+cc/ob7ggj6SZ7Z9MyWZrevle9VbUsM9eqkDinkW8/cAPi4U+m1UtuHT36oe3apE8 xnr4XsGDa46BRZEHZ+orQ3Cg1YPK1VGUUYflk347oTbT/x+rn2BOYBsuFssoBXHX/rjy An0Q== X-Gm-Message-State: ALKqPwcFPMS/BrxJWPoWWz4qP36zxyZTb6RdatPJ1se/Wa2/w3/1p5zN 8jyUgnYNpku4/X9xhCWbn0UlGolvYnr+G01pVCLYjw== X-Google-Smtp-Source: ADUXVKL8EIJ6WtOJCD/1drlywf+512dv1G3N0zvnlT82ItRuMkrnJIgxVpMGN+S1iv0lbL2APvsncSFYv+ZFEjBte2U= X-Received: by 2002:a9d:330b:: with SMTP id f11-v6mr3805538otc.299.1527341900657; Sat, 26 May 2018 06:38:20 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Lakhan Shiva Date: Sat, 26 May 2018 19:08:08 +0530 Message-ID: Subject: Re: Why is there no bus_dmamap_load_sg()? To: pratyush@freebsd.org Cc: freebsd-hackers@freebsd.org, jaggi@freebsd.org, Edward Tomasz Napierala Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.26 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 26 May 2018 13:38:22 -0000 Hi, I think nobody wanted this before. As you have the need for it in your project you should go ahead and create the service. Again, I am not 100% sure, correct me if i am wrong. Thanks, Lakhan On Sat, May 26, 2018 at 2:41 PM Pratyush Yadav wrote: > Hi all, > > I am working on Xen this summer [0], and I have to use the bus_dma(9) > interface extensively during the course of the project. > > I was looking at the man page and I notice the function > bus_dmamap_load_mbuf_sg() which directly returns the segment array to > the client. But a similar variant of bus_dmamap_load() is missing. > This variant would be useful to me and help me in my work. > > Is there a reason the sg variant was only implemented for mbufs? > > I was looking at the code in sys/kern/subr_bus_dma.c and a > bus_dmamap_load_sg() does not look too difficult to implement. Is it > ok if I submit a patch implementing it? > > -- > Regards, > Pratyush Yadav > > > [0] > https://wiki.freebsd.org/SummerOfCode2018Projects/ImportXenbus_dmaFromOpenBSD > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" >