From nobody Wed Dec 28 06:33:04 2022 X-Original-To: bugs@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4NhhXx2wpRz1Lj8d for ; Wed, 28 Dec 2022 06:33:05 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4NhhXx0h9Zz3xg0 for ; Wed, 28 Dec 2022 06:33:05 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1672209185; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=mHim223AcpgOfny02h/CdQJOCSSMSDGSxoxpSuScoH0=; b=H2XDhAf7W2wAj5uTXPaVG9vppNW0ClXH5HXKfRyNMzeJXJ1Xo509hNXEr2ghzdqpMfWLIt 4fFH8l1s/EZylRdZIGjEhOpLdUIlkPCiu8N7rn6f6rnDD+oMic+IbgvHlVRUVRbzI10nji MmCzX0Lngi/YPSlvgWIA8WGlJZuc5FuM4GzB1sUL4DJ3rAC2VOGIKGdKLePxu2C5Xg6rJU 73MPHoQDIOsvK7d6wxpBAt9TQkGKfau9MDks4eNVWWNx5j3Flv0y7+oJOFMkzmv58rFjFR rF/tDHbVI+Ga/4mb9EY8oFzdP3CP3EFZxZTpfQcIR676ixJkg6/20J5rmXZEuQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1672209185; a=rsa-sha256; cv=none; b=a46hCHz3LLk/0MbXP281Tp7KfQmR8h7ZkuOVeo2XMfQ04w/zCjurur4vLPTj/qDDv42BLo NHPWmQ5CdddHyeIAPPcXtiKkI4CvG/nmsRTxkS2IULjB5lYmJ9suE8pMfJh8rvuATT1gTP zmd8hJp/rPkU+yC4lh4/l2G+4jrc1KMzs21D+AjBGZqf8Ug2eoJ1mLHLywg2UArIttX85e WD7V7UDTkt0Kr4C4yh0GIZqXu/LaHtgfiV1f6ohRI/CG8sxSDpTmPfk6L7v9xok53TFzb8 NTlBiOZBNtGdf1eq5M4GW+TvJw/IwoLMfq5hZlO1qc3e+Kp1DcZkfTp25nMIaA== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4NhhXw6s76zgPc for ; Wed, 28 Dec 2022 06:33:04 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 2BS6X49p084178 for ; Wed, 28 Dec 2022 06:33:04 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 2BS6X43R084177 for bugs@FreeBSD.org; Wed, 28 Dec 2022 06:33:04 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 268610] mounting cdevs as regular vnodes Date: Wed, 28 Dec 2022 06:33:04 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: ybungalobill@gmail.com X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Bug reports List-Archive: https://lists.freebsd.org/archives/freebsd-bugs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-bugs@freebsd.org MIME-Version: 1.0 X-ThisMailContainsUnwantedMimeParts: N https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D268610 Bug ID: 268610 Summary: mounting cdevs as regular vnodes Product: Base System Version: CURRENT Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: ybungalobill@gmail.com Created attachment 239079 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=3D239079&action= =3Dedit prototype implementation FreeBSD does not implement filesystem caching for i/o done on cdevs. This m= akes i/o slow when done on raw devices, and renders impossible to mmap a cdev (w= hich is supported by some other OSes). I'm attaching my implementation of a 'rawfs' filesystem: mount -t rawfs /dev/xxx /mnt then i/o on /mnt will be fully buffered, while giving a read-only view of t= he raw data on the device. This can be seen as an inverse of `mdconfig`. If there's an interest in including this functionality in the base system, please review the attached code. As it's evident, I had no prior experience working with FreeBSD kernel code, so any comments are welcome. --=20 You are receiving this mail because: You are the assignee for the bug.=