Messages in this thread | | | Subject | Re: cdrecord dev=ATA cannont scanbus as non-root [u] | From | "Martin Schlemmer [c]" <> | Date | Thu, 02 Dec 2004 23:50:52 +0200 |
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On Thu, 2004-12-02 at 17:23 +0100, Radoslaw Szkodzinski wrote: > On Wednesday 01 of December 2004 22:16, Martin Schlemmer [c] wrote: > > On Tue, 2004-11-30 at 08:16 +0100, Jens Axboe wrote: > > > On Mon, Nov 29 2004, J.A. Magallon wrote: > > > > dev=ATAPI uses ide-scsi interface, through /dev/sgX. And: > > > > > scsibus: -1 target: -1 lun: -1 > > > > > Warning: Using ATA Packet interface. > > > > > Warning: The related Linux kernel interface code seems to be > > > > > unmaintained. Warning: There is absolutely NO DMA, operations thus > > > > > are slow. > > > > > > > > dev=ATA uses direct IDE burning. Try that as root. In my box, as root: > > > > > > Oh no, not this again... Please check the facts: the ATAPI method uses > > > the SG_IO ioctl, which is direct-to-device. It does _not_ go through > > > /dev/sgX, unless you actually give /dev/sgX as the device name. It has > > > nothing to do with ide-scsi. Period. > > > > > > ATA uses CDROM_SEND_PACKET. This has nothing to do with direct IDE > > > burning, it's a crippled interface from the CDROM layer that should not > > > be used for anything. scsi-linux-ata.c should be ripped from the > > > cdrecord sources, or at least cdrecord should _never_ select that > > > transport for 2.6 kernels. For 2.4 you are far better off using > > > ide-scsi. > > > > > > > The scan through ATA lasts much less than with ATAPI, and you can burn > > > > with dev=ATA:1,0,0 or dev=/dev/burner, which is the new recommended > > > > way. > > > > > > No! ATAPI is the recommended way. > > > > Ok, so I am a bit confused here. We basically have 3 ways to use > > cdrecord on linux-2.6 without ide-scsi: > > > > 1) cdrecord dev=/dev/hdx > > 2) cdrecord dev=ATA > > 3) cdrecord dev=ATAPI > > > > Now, if I run all three and grep for '^Warning', I get: > > > > ----- > > $ cdrecord dev=/dev/cdrw -scanbus 2>&1 | grep '^Warning' > > Warning: Open by 'devname' is unintentional and not supported. > > $ cdrecord dev=ATA -scanbus 2>&1 | grep '^Warning' > > Warning: Using badly designed ATAPI via /dev/hd* interface. > > $ cdrecord dev=ATAPI -scanbus 2>&1 | grep '^Warning' > > Warning: Using ATA Packet interface. > > Warning: The related Linux kernel interface code seems to be unmaintained. > > Warning: There is absolutely NO DMA, operations thus are slow. > > $ > > ----- > > > > Which means: > > > > 1) dev=/dev/hdx - Open by 'devname' is unintentional and not supported. > > 2) dev=ATA - Using badly designed ATAPI via /dev/hd* interface. > > 3) dev=ATAPI - Using ATA Packet interface. > > (And some nice things about it not being maintained and > > slow) > > > > Well, dev=ATA:nr,nr,nr will not produce any warning and works correctly with > full performance. > dev=ATAPI:* gives bad performance and as stated above, shouldn't be used. > dev=/dev/hdx is just the same as dev=ATA:/dev/hdx, you can of course replace > it with correct numbers if you know them or an alias > in /etc/defaults/cdrecord.dfl (The path's from Gentoo, may be different > elsewhere.)
Yes, I know .. its just that I have been under the impression (and also what experience shows) that 'dev=/dev/hdx' and 'dev=ATA' is the same thing, with 'dev=ATAPI' the depreciated one, but Jens stated differently above ...
-- Martin Schlemmer
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