Re: CD-ROM settings and hardware resources...

Re: CD-ROM settings and hardware resources...

[Robert Couture]

Originally to: Bryan Simmons

Hello Bryan!

On 20/10/2002, Bryan Simmons was caught whispering to All about
Re: CD-ROM settings and hardware resources....

 BS> The CDs I'm trying to read were made in Windows (98, 2000, XP) with this
 BS> very same drive about a year ago.  They all contain home-made movies
 BS> that I created in XP.  The range in sizes is 9MB to 200MB.  Now, I have
 BS> never been able to play any of them directly off of the disk in Windows,
 BS> but I have always been able to transfer them from CD to hard disk.  My
 BS> problem in Linux is that the drive "stalls" during a copy or a read of
 BS> the media during playback in xine or kaboodle or xmovie, etc...  It
 BS> would play the first 30 seconds of the film and then stall out.  The
 BS> media program freezes and the drive is locked until I kill the processes
 BS> accessing it.  The same is true when I attempt a copy from CD to hard
 BS> drive in Konqueror.  The copy window says it transfered 4MB and then the
 BS> drive status windows says "stalled" and that's as far as I can get.

To be honest, the symptoms you describe sounds more like a bad CD than
anything to do with Linux itself.  This is based on you needing to copy the
files to play them in Windows.  There are likely bad "sectors" that re
recoverable with multiple reads and error correction.  That would explain it
not working in the Windows and Linux media players.

Just a thought.

Robert.

<-> Gateway Information.
This message originated from a Fidonet System (http://www.fidonet.org)
and was gated at TCOB1 (http://www.tcob1.net)
Please do not respond direct to this message but via the list


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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

You missed the part where I said the only way to retrieve the files was
in Windows and that I wanted to enable whatever error correction or
multiple read settings that Windows has but while I'm in Linux.

Any ideas?


On Tue, 2002-10-22 at 09:25, Robert Couture wrote:
> Originally to: Bryan Simmons
> 
> Hello Bryan!
> 
> On 20/10/2002, Bryan Simmons was caught whispering to All about
> Re: CD-ROM settings and hardware resources....
> 
>  BS> The CDs I'm trying to read were made in Windows (98, 2000, XP) with this
>  BS> very same drive about a year ago.  They all contain home-made movies
>  BS> that I created in XP.  The range in sizes is 9MB to 200MB.  Now, I have
>  BS> never been able to play any of them directly off of the disk in Windows,
>  BS> but I have always been able to transfer them from CD to hard disk.  My
>  BS> problem in Linux is that the drive "stalls" during a copy or a read of
>  BS> the media during playback in xine or kaboodle or xmovie, etc...  It
>  BS> would play the first 30 seconds of the film and then stall out.  The
>  BS> media program freezes and the drive is locked until I kill the processes
>  BS> accessing it.  The same is true when I attempt a copy from CD to hard
>  BS> drive in Konqueror.  The copy window says it transfered 4MB and then the
>  BS> drive status windows says "stalled" and that's as far as I can get.
> 
> To be honest, the symptoms you describe sounds more like a bad CD than
> anything to do with Linux itself.  This is based on you needing to copy the
> files to play them in Windows.  There are likely bad "sectors" that re
> recoverable with multiple reads and error correction.  That would explain it
> not working in the Windows and Linux media players.
> 
> Just a thought.
> 
> Robert.
> 
> <-> Gateway Information.
> This message originated from a Fidonet System (http://www.fidonet.org)
> and was gated at TCOB1 (http://www.tcob1.net)
> Please do not respond direct to this message but via the list
> 
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
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> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Regards,

Bryan Simmons 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 On Integrity:

 "I'm going to be as good as they let me and
  as mean as they make me, and they all know
  that.  I don't ever lie. If I tell you a
  rooster can fly, get the harness."

   --Burl Cain, Louisiana State Pen Warden
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 

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Re: CD-ROM settings and hardware resources...

[pa3gcu]

On Tuesday 22 October 2002 19:45, Bryan Simmons wrote:
> You missed the part where I said the only way to retrieve the files was
> in Windows and that I wanted to enable whatever error correction or
> multiple read settings that Windows has but while I'm in Linux.
>
> Any ideas?

It sounds to me like you dont have dma set for the cdrom.

man hdparm will explain howto turn it on.

If thats not it then please disregard this mail.

-- 
Regards Richard
pa3gcu@zeelandnet.nl
http://people.zeelandnet.nl/pa3gcu/

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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

The CD-ROM in question is a CD-RW.  The system set it up as /dev/scd0
which is not accessible from hdparam.  if I turn it into an ide device,
I will no longer be able to write CDs with it.

Does anyone know a way around this?  I can't hardly believe that all the
millions of Linux users have been, and still are, stuck with CD-RWs that
have to masquerade as SCSI devices.


On Wed, 2002-10-23 at 11:49, pa3gcu wrote:
> On Tuesday 22 October 2002 19:45, Bryan Simmons wrote:
> > You missed the part where I said the only way to retrieve the files was
> > in Windows and that I wanted to enable whatever error correction or
> > multiple read settings that Windows has but while I'm in Linux.
> >
> > Any ideas?
> 
> It sounds to me like you dont have dma set for the cdrom.
> 
> man hdparm will explain howto turn it on.
> 
> If thats not it then please disregard this mail.
> 
> -- 
> Regards Richard
> pa3gcu@zeelandnet.nl
> http://people.zeelandnet.nl/pa3gcu/
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Regards,

Bryan Simmons 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 On Integrity:

 "I'm going to be as good as they let me and
  as mean as they make me, and they all know
  that.  I don't ever lie. If I tell you a
  rooster can fly, get the harness."

   --Burl Cain, Louisiana State Pen Warden
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 

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Re: CD-ROM settings and hardware resources...

[Ray Olszewski]

At 03:20 PM 10/23/02 -0400, Bryan Simmons wrote:
>The CD-ROM in question is a CD-RW.  The system set it up as /dev/scd0
>which is not accessible from hdparam.  if I turn it into an ide device,
>I will no longer be able to write CDs with it.

The underlying ide device (/dev/hd*) remains accessable to hdparm (NOT 
"hdparam"). You change the DMA setting on the "real" IDE device, not the 
emulated SCSI device. (I'm assuming here that the drive really is an IDE 
drive, and you are using the kernel's ide-scsi driver to "turn it into" a 
scsi device for cdrecord or cdrdao or whatever you use to burn. Details 
matter in troubleshooting discussions.)

>Does anyone know a way around this?  I can't hardly believe that all the
>millions of Linux users have been, and still are, stuck with CD-RWs that
>have to masquerade as SCSI devices.

Believe it. Or take it up with the folks who write the CD burning programs 
(at least the two I named above, anyway).


--
-------------------------------------------"Never tell me the odds!"--------
Ray Olszewski					-- Han Solo
Palo Alto, California, USA			  ray@comarre.com
-------------------------------------------------------------------------------

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Re: CD-ROM settings and hardware resources...

[pa3gcu]

On Wednesday 23 October 2002 19:20, Bryan Simmons wrote:
> The CD-ROM in question is a CD-RW.  The system set it up as /dev/scd0
> which is not accessible from hdparam.  if I turn it into an ide device,
> I will no longer be able to write CDs with it.

You are missing the point, your cd-rom is no differnt to anyone else's, you 
set things like dma with hdparm but you do it on the underlting device which 
is /dev/hdX where X is a letter a b c or d.

a = master device primary controller.
b = slave   device primary controller.
c = master device sec controller.
d = slave   device sec controller.

hdparm /dev/hdc shows drive info;
hdparm -d1 /dev/hdc
will set dma to "on" on drive "c" as per above. /dev/scd0 is irrelavant.
 
>
> Does anyone know a way around this?  I can't hardly believe that all the
> millions of Linux users have been, and still are, stuck with CD-RWs that
> have to masquerade as SCSI devices.

There is no way around it, simply read the proper documentation, in this case 
the CD-Writing HOWTO.
IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in 
widows as well.
If you find a better way you can tell us millions how you did it then.

-- 
Regards Richard
pa3gcu@zeelandnet.nl
http://people.zeelandnet.nl/pa3gcu/

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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

Perhaps dma wasn't the problem.  Here's the output when I execute hdparm
on /dev/hdc (my CD-RW):

/dev/hdc:
 HDIO_GET_MULTCOUNT failed: Input/output error
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 BLKRAGET failed: Input/output error
 HDIO_GETGEO failed: Invalid argument

When I try to retrieve the read-ahead setting: hdparm -a /dev/hdc I get:

/dev/hdc:
 BLKRAGET failed: Input/output error

Does anyone know of a web site where I can research these errors?  Or
does anyone have an idea, off the top of their heads, why this could be
happening?



On Wed, 2002-10-23 at 16:36, pa3gcu wrote:
> On Wednesday 23 October 2002 19:20, Bryan Simmons wrote:
> > The CD-ROM in question is a CD-RW.  The system set it up as /dev/scd0
> > which is not accessible from hdparam.  if I turn it into an ide device,
> > I will no longer be able to write CDs with it.
> 
> You are missing the point, your cd-rom is no differnt to anyone else's, you 
> set things like dma with hdparm but you do it on the underlting device which 
> is /dev/hdX where X is a letter a b c or d.
> 
> a = master device primary controller.
> b = slave   device primary controller.
> c = master device sec controller.
> d = slave   device sec controller.
> 
> hdparm /dev/hdc shows drive info;
> hdparm -d1 /dev/hdc
> will set dma to "on" on drive "c" as per above. /dev/scd0 is irrelavant.
>  
> >
> > Does anyone know a way around this?  I can't hardly believe that all the
> > millions of Linux users have been, and still are, stuck with CD-RWs that
> > have to masquerade as SCSI devices.
> 
> There is no way around it, simply read the proper documentation, in this case 
> the CD-Writing HOWTO.
> IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in 
> widows as well.
> If you find a better way you can tell us millions how you did it then.
> 
> -- 
> Regards Richard
> pa3gcu@zeelandnet.nl
> http://people.zeelandnet.nl/pa3gcu/
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
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> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Regards,

Bryan Simmons 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 On Integrity:

 "I'm going to be as good as they let me and
  as mean as they make me, and they all know
  that.  I don't ever lie. If I tell you a
  rooster can fly, get the harness."

   --Burl Cain, Louisiana State Pen Warden
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 

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Re: CD-ROM settings and hardware resources...

[pa3gcu]

On Wednesday 23 October 2002 21:51, Bryan Simmons wrote:
> Perhaps dma wasn't the problem.  Here's the output when I execute hdparm
> on /dev/hdc (my CD-RW):
>
> /dev/hdc:
>  HDIO_GET_MULTCOUNT failed: Input/output error
>  IO_support   =  1 (32-bit)
>  unmaskirq    =  1 (on)
>  using_dma    =  1 (on)
>  keepsettings =  0 (off)
>  readonly     =  0 (off)
>  BLKRAGET failed: Input/output error
>  HDIO_GETGEO failed: Invalid argument
>
> When I try to retrieve the read-ahead setting: hdparm -a /dev/hdc I get:
>
> /dev/hdc:
>  BLKRAGET failed: Input/output error

There are some settings which do not apply to cdroms, one of which is 
BLRAGET, the other shown above is geometry settings of which a cdrom has not, 
so that will fail as well.

-- 
Regards Richard
pa3gcu@zeelandnet.nl
http://people.zeelandnet.nl/pa3gcu/

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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

OK, but doesn't a CD-ROM have a read-ahead setting?


On Thu, 2002-10-24 at 02:40, pa3gcu wrote:
> On Wednesday 23 October 2002 21:51, Bryan Simmons wrote:
> > Perhaps dma wasn't the problem.  Here's the output when I execute hdparm
> > on /dev/hdc (my CD-RW):
> >
> > /dev/hdc:
> >  HDIO_GET_MULTCOUNT failed: Input/output error
> >  IO_support   =  1 (32-bit)
> >  unmaskirq    =  1 (on)
> >  using_dma    =  1 (on)
> >  keepsettings =  0 (off)
> >  readonly     =  0 (off)
> >  BLKRAGET failed: Input/output error
> >  HDIO_GETGEO failed: Invalid argument
> >
> > When I try to retrieve the read-ahead setting: hdparm -a /dev/hdc I get:
> >
> > /dev/hdc:
> >  BLKRAGET failed: Input/output error
> 
> There are some settings which do not apply to cdroms, one of which is 
> BLRAGET, the other shown above is geometry settings of which a cdrom has not, 
> so that will fail as well.
> 
> -- 
> Regards Richard
> pa3gcu@zeelandnet.nl
> http://people.zeelandnet.nl/pa3gcu/
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
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-- 
Regards,

Bryan Simmons 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 On Integrity:

 "I'm going to be as good as they let me and
  as mean as they make me, and they all know
  that.  I don't ever lie. If I tell you a
  rooster can fly, get the harness."

   --Burl Cain, Louisiana State Pen Warden
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 

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Re: CD-ROM settings and hardware resources...

[pa3gcu]

On Thursday 24 October 2002 10:35, Bryan Simmons wrote:
> OK, but doesn't a CD-ROM have a read-ahead setting?

Yes, but unfortunatly not when SCSI emu is used.
So if you use you cdr for both writing and reading then you could always use 
ide for reading and then scsi for writing, not very efficent but i see no 
other option at the present time.

-- 
Regards Richard
pa3gcu@zeelandnet.nl
http://people.zeelandnet.nl/pa3gcu/

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Re: CD-ROM settings and hardware resources...

[Ray Olszewski]

At 05:51 PM 10/23/02 -0400, Bryan Simmons wrote:
>Perhaps dma wasn't the problem.  Here's the output when I execute hdparm
>on /dev/hdc (my CD-RW):
>
>/dev/hdc:
>  HDIO_GET_MULTCOUNT failed: Input/output error
>  IO_support   =  1 (32-bit)
>  unmaskirq    =  1 (on)
>  using_dma    =  1 (on)
>  keepsettings =  0 (off)
>  readonly     =  0 (off)
>  BLKRAGET failed: Input/output error
>  HDIO_GETGEO failed: Invalid argument
>
>When I try to retrieve the read-ahead setting: hdparm -a /dev/hdc I get:
>
>/dev/hdc:
>  BLKRAGET failed: Input/output error
>
>Does anyone know of a web site where I can research these errors?  Or
>does anyone have an idea, off the top of their heads, why this could be
>happening?


I don't have a reference, but I did take a minute to get the same results 
for my two drives. Both work fine. Here is what I get:

First, for hdc, which is a DVD drive acessed via IDE --

         waverly:/home/autovcr# hdparm /dev/hdc

         /dev/hdc:
         HDIO_GET_MULTCOUNT failed: Invalid argument
         IO_support   =  0 (default 16-bit)
         unmaskirq    =  0 (off)
         using_dma    =  1 (on)
         keepsettings =  0 (off)
         readonly     =  1 (on)
         readahead    =  8 (on)
         HDIO_GETGEO failed: Invalid argument

Now for hdd, my CD-RW drive, accessed via ide-scsi emulation --

         waverly:/home/autovcr# hdparm /dev/hdd

         /dev/hdd:
         HDIO_GET_MULTCOUNT failed: Input/output error
         IO_support   =  0 (default 16-bit)
         unmaskirq    =  0 (off)
         using_dma    =  1 (on)
         keepsettings =  0 (off)
         readonly     =  0 (off)
         BLKRAGET failed: Input/output error
         HDIO_GETGEO failed: Invalid argument

And just to complete the comparison, here is one of the same system's hard 
disks --

         waverly:/home/autovcr# hdparm /dev/hdb

         /dev/hdb:
         multcount    = 16 (on)
         IO_support   =  0 (default 16-bit)
         unmaskirq    =  0 (off)
         using_dma    =  1 (on)
         keepsettings =  0 (off)
         readonly     =  0 (off)
         readahead    =  8 (on)
         geometry     = 15017/255/63, sectors = 241254720, start = 0

 From this, I infer that the two errors I see on both removable drives 
reflect differences between CD drives and hard disks. The BLKRAGET error is 
somehow associated with use of scsi-ide emulation, but does not interfere 
with my ordinary use of the drive.

So ... you might, just as a test, remove the scsi-ide emulation and see if 
you can then read the problem CD. If not, you can then check the readahead 
setting and see if it seems to be wrong. More likely, since the problem is 
specific to the one disk, there is something unusual about it that needs to 
be corrected. When it is mounted, does it return sensible results in its 
listings of "df" and "ls -l"? Can you "dd" it to an iso image? Is it 
iso9660 compliant?


--
-------------------------------------------"Never tell me the odds!"--------
Ray Olszewski					-- Han Solo
Palo Alto, California, USA			  ray@comarre.com
-------------------------------------------------------------------------------

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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

On Thu, 2002-10-24 at 03:01, Ray Olszewski wrote:
> At 05:51 PM 10/23/02 -0400, Bryan Simmons wrote:
> >Perhaps dma wasn't the problem.  Here's the output when I execute hdparm
> >on /dev/hdc (my CD-RW):
> >
> >/dev/hdc:
> >  HDIO_GET_MULTCOUNT failed: Input/output error
> >  IO_support   =  1 (32-bit)
> >  unmaskirq    =  1 (on)
> >  using_dma    =  1 (on)
> >  keepsettings =  0 (off)
> >  readonly     =  0 (off)
> >  BLKRAGET failed: Input/output error
> >  HDIO_GETGEO failed: Invalid argument
> >
> >When I try to retrieve the read-ahead setting: hdparm -a /dev/hdc I get:
> >
> >/dev/hdc:
> >  BLKRAGET failed: Input/output error
> >
> >Does anyone know of a web site where I can research these errors?  Or
> >does anyone have an idea, off the top of their heads, why this could be
> >happening?
> 
> 
> I don't have a reference, but I did take a minute to get the same results 
> for my two drives. Both work fine. Here is what I get:
> 
> First, for hdc, which is a DVD drive acessed via IDE --
> 
>          waverly:/home/autovcr# hdparm /dev/hdc
> 
>          /dev/hdc:
>          HDIO_GET_MULTCOUNT failed: Invalid argument
>          IO_support   =  0 (default 16-bit)
>          unmaskirq    =  0 (off)
>          using_dma    =  1 (on)
>          keepsettings =  0 (off)
>          readonly     =  1 (on)
>          readahead    =  8 (on)
>          HDIO_GETGEO failed: Invalid argument
> 
> Now for hdd, my CD-RW drive, accessed via ide-scsi emulation --
> 
>          waverly:/home/autovcr# hdparm /dev/hdd
> 
>          /dev/hdd:
>          HDIO_GET_MULTCOUNT failed: Input/output error
>          IO_support   =  0 (default 16-bit)
>          unmaskirq    =  0 (off)
>          using_dma    =  1 (on)
>          keepsettings =  0 (off)
>          readonly     =  0 (off)
>          BLKRAGET failed: Input/output error
>          HDIO_GETGEO failed: Invalid argument
> 
> And just to complete the comparison, here is one of the same system's hard 
> disks --
> 
>          waverly:/home/autovcr# hdparm /dev/hdb
> 
>          /dev/hdb:
>          multcount    = 16 (on)
>          IO_support   =  0 (default 16-bit)
>          unmaskirq    =  0 (off)
>          using_dma    =  1 (on)
>          keepsettings =  0 (off)
>          readonly     =  0 (off)
>          readahead    =  8 (on)
>          geometry     = 15017/255/63, sectors = 241254720, start = 0
> 
>  From this, I infer that the two errors I see on both removable drives 
> reflect differences between CD drives and hard disks. The BLKRAGET error is 
> somehow associated with use of scsi-ide emulation, but does not interfere 
> with my ordinary use of the drive.
> 
> So ... you might, just as a test, remove the scsi-ide emulation and see if 
> you can then read the problem CD. If not, you can then check the readahead 
> setting and see if it seems to be wrong. 
For some reason, I can't access this setting at all.  it doesn't show up
when using the hdparm /dev/hdc command and when asking for it directly,
hdparm -a /dev/hdc I get an input/output error.


More likely, since the problem is 
> specific to the one disk, there is something unusual about it that needs to 
> be corrected. When it is mounted, does it return sensible results in its 
> listings of "df" and "ls -l"? 
I suppose so.  I can see and at least start to copy all the files on the
disk.  

Can you "dd" it to an iso image? Is it 
> iso9660 compliant?
I really don't know since I'm kinda ignorant to the different
file-system types.

I remember when first installing CD burning software in Windows (please
hear me out) it told me to turn off the read-ahead on the CD-ROM to
allow me to read all CD-R media.  Is this relevant in Linux?

> 
> 
> --
> -------------------------------------------"Never tell me the odds!"--------
> Ray Olszewski					-- Han Solo
> Palo Alto, California, USA			  ray@comarre.com
> -------------------------------------------------------------------------------
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Regards,

Bryan Simmons 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 On Integrity:

 "I'm going to be as good as they let me and
  as mean as they make me, and they all know
  that.  I don't ever lie. If I tell you a
  rooster can fly, get the harness."

   --Burl Cain, Louisiana State Pen Warden
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 

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Re: CD-ROM settings and hardware resources...

[pa3gcu]

On Wednesday 23 October 2002 21:46, you wrote:

I have directed a reply to the list as i find it relavant.

> According to a conversation I had with another helper on this list,
> there is an experimental IDE CR driver that does away with the scsi
> emulation.  I was under the impression that this was the only way to
> turn on the dma setting.

Then i stand corrected, as i know nothing of such a driver, it could be that 
such a driver is being developed into 2.5 kernels, however those kernels are 
not things to use on normal systems as they are what they are, "experimental".

Perhaps the "other helper" on this list would like to tell us where to find 
information on this driver.

>
> Anyway, I ask these questions because I have a lot of other things to
> deal with from day to day.  Sometimes I don't spend enough time
> researching solutions because of distractions.

That is a problem we all camp with.
Too be honest i made a mistake in the mail below, i said the CD-Writing-HOWTO 
explained about 'hdparm' i was wrong, i read it somewhere else, its just i 
cant remember where it was, possably in the README of Xcdroast which i use 
for buring CD's or some other program README.

>
> I could have done without the sarcasm, but thanks for the info.

It was not meant as sarcasm, if you took it that way then please accept my 
appols.

>
> On Wed, 2002-10-23 at 16:36, pa3gcu wrote:
> > On Wednesday 23 October 2002 19:20, Bryan Simmons wrote:
> > > The CD-ROM in question is a CD-RW.  The system set it up as /dev/scd0
> > > which is not accessible from hdparam.  if I turn it into an ide device,
> > > I will no longer be able to write CDs with it.
> >
> > You are missing the point, your cd-rom is no differnt to anyone else's,
> > you set things like dma with hdparm but you do it on the underlting
> > device which is /dev/hdX where X is a letter a b c or d.
> >
> > a = master device primary controller.
> > b = slave   device primary controller.
> > c = master device sec controller.
> > d = slave   device sec controller.
> >
> > hdparm /dev/hdc shows drive info;
> > hdparm -d1 /dev/hdc
> > will set dma to "on" on drive "c" as per above. /dev/scd0 is irrelavant.
> >
> > > Does anyone know a way around this?  I can't hardly believe that all
> > > the millions of Linux users have been, and still are, stuck with CD-RWs
> > > that have to masquerade as SCSI devices.
> >
> > There is no way around it, simply read the proper documentation, in this
> > case the CD-Writing HOWTO.
> > IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in
> > widows as well.
> > If you find a better way you can tell us millions how you did it then.
> >
> > --
> > Regards Richard
> > pa3gcu@zeelandnet.nl
> > http://people.zeelandnet.nl/pa3gcu/

-- 
Regards Richard
pa3gcu@zeelandnet.nl
http://people.zeelandnet.nl/pa3gcu/

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Re: CD-ROM settings and hardware resources...

[jbradford]

> > According to a conversation I had with another helper on this list,
> > there is an experimental IDE CR driver that does away with the scsi
> > emulation.  I was under the impression that this was the only way to
> > turn on the dma setting.
> 
> Then i stand corrected, as i know nothing of such a driver, it could be that 
> such a driver is being developed into 2.5 kernels, however those kernels are 
> not things to use on normal systems as they are what they are, "experimental".
> 
> Perhaps the "other helper" on this list would like to tell us where to find 
> information on this driver.

I believe I am "the other helper" :-)

Yes, you are right, 2.5 contains changes that will eventually allow cd
recording without using SCSI emulation:

http://groups.google.com/groups?q=cdrecord+%22torvalds%40transmeta.com%22&hl=en&lr=&ie=UTF-8&scoring=r&selm=Pine.LNX.4.44.0210161437010.1108-100000%40penguin.transmeta.com.lucky.linux.kernel&rnum=3

By the way, I'm not sure what enabling/disabling DMA has to do with
reading a faulty CD-ROM.  It's not like you're enabling/disabling
UDMA, which has error correction to detect errors on the _bus_.

John.
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Re: CD-ROM settings and hardware resources...

[Ray Olszewski]

At 05:04 PM 10/24/02 +0100, jbradford@dial.pipex.com wrote:
[...]
>By the way, I'm not sure what enabling/disabling DMA has to do with
>reading a faulty CD-ROM.  It's not like you're enabling/disabling
>UDMA, which has error correction to detect errors on the _bus_.

Enabling DMA has nothing (that I know of) to do with reading a faulty 
CD-ROM. I originally suggested it as a solution because in his first 
message, Bryan (the original poster) described his problems in a very vague 
way ("has trouble reading large files"). That sounded to me like it might 
refer to a problem I have seen ... namely, a lot of dropped frames ... when 
doing video playback from a CD drive that does not have DMA enabled. 
Enabling DMA does fix that, since it is a timing issue.

When Bryan's subsequent messages made it clear that (a) this was a problem 
limited to a specific, home-burned CD and (b) the problem occurred in 
non-timing-sensitive settings like copying to a hard disk, I suggested that 
the problem was with the CD's filesystem, not DMA.

The lesson here is that vague descriptions of problems elicit irrelevant 
solutions. I hope everyone who reads this list takes that lesson to heart.


--
-------------------------------------------"Never tell me the odds!"--------
Ray Olszewski					-- Han Solo
Palo Alto, California, USA			  ray@comarre.com
-------------------------------------------------------------------------------

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Re: CD-ROM settings and hardware resources...

[jbradford]

> > Does anyone know a way around this?  I can't hardly believe that all the
> > millions of Linux users have been, and still are, stuck with CD-RWs that
> > have to masquerade as SCSI devices.
> 
> There is no way around it, simply read the proper documentation, in this case 
> the CD-Writing HOWTO.
> IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in 
> widows as well.
> If you find a better way you can tell us millions how you did it then.

There will soon be a better way - Linus himself mentioned using the
standard IDE devices for cd recording, last Tuesday.

Expect to see cd recording with native IDE devices once the 2.6 kernel
is ready.

Incidently, IDE devices masquerading as SCSI is not as unusual as it
might first appear - ATAPI is basically a way to send SCSI commands
over the IDE bus.

John.
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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

Shows how much I know about basic system design...

In fact, I was shocked to learn last night that ext2 uses linked lists
to keep track of files in a directory.  Why is this?  Did the guys who
wrote the file system specs go to school for computer science?  I can't
tell you how many times my cmsc professors have told us that the linked
list is totally inferior to the tree.  At least, it is when it comes to
large sets of data.  Perhaps the ext2 guys never saw the need for
extremely large sets of files in a single directory, but still, even
when hashing, it is suggested that you not handle collisions with linked
lists...
Stacks and queues are one thing (when used for temporary operations,
like iterators and memory management).  But persistent data is another. 
I would never want to store stuff in a list if it is always going to be
accessed, growing and shrinking...

On Thu, 2002-10-24 at 07:11, jbradford@dial.pipex.com wrote:
> > > Does anyone know a way around this?  I can't hardly believe that all the
> > > millions of Linux users have been, and still are, stuck with CD-RWs that
> > > have to masquerade as SCSI devices.
> > 
> > There is no way around it, simply read the proper documentation, in this case 
> > the CD-Writing HOWTO.
> > IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in 
> > widows as well.
> > If you find a better way you can tell us millions how you did it then.
> 
> There will soon be a better way - Linus himself mentioned using the
> standard IDE devices for cd recording, last Tuesday.
> 
> Expect to see cd recording with native IDE devices once the 2.6 kernel
> is ready.
> 
> Incidently, IDE devices masquerading as SCSI is not as unusual as it
> might first appear - ATAPI is basically a way to send SCSI commands
> over the IDE bus.
> 
> John.
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Regards,

Bryan Simmons 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 On Integrity:

 "I'm going to be as good as they let me and
  as mean as they make me, and they all know
  that.  I don't ever lie. If I tell you a
  rooster can fly, get the harness."

   --Burl Cain, Louisiana State Pen Warden
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 

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Re: CD-ROM settings and hardware resources...

[Jude DaShiell]

Do any of the Linux file systems use a tree rather than linked lists?



On 24 Oct 2002, Bryan Simmons wrote:

> Shows how much I know about basic system design...
>
> In fact, I was shocked to learn last night that ext2 uses linked lists
> to keep track of files in a directory.  Why is this?  Did the guys who
> wrote the file system specs go to school for computer science?  I can't
> tell you how many times my cmsc professors have told us that the linked
> list is totally inferior to the tree.  At least, it is when it comes to
> large sets of data.  Perhaps the ext2 guys never saw the need for
> extremely large sets of files in a single directory, but still, even
> when hashing, it is suggested that you not handle collisions with linked
> lists...
> Stacks and queues are one thing (when used for temporary operations,
> like iterators and memory management).  But persistent data is another.
> I would never want to store stuff in a list if it is always going to be
> accessed, growing and shrinking...
>
> On Thu, 2002-10-24 at 07:11, jbradford@dial.pipex.com wrote:
> > > > Does anyone know a way around this?  I can't hardly believe that all the
> > > > millions of Linux users have been, and still are, stuck with CD-RWs that
> > > > have to masquerade as SCSI devices.
> > >
> > > There is no way around it, simply read the proper documentation, in this case
> > > the CD-Writing HOWTO.
> > > IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in
> > > widows as well.
> > > If you find a better way you can tell us millions how you did it then.
> >
> > There will soon be a better way - Linus himself mentioned using the
> > standard IDE devices for cd recording, last Tuesday.
> >
> > Expect to see cd recording with native IDE devices once the 2.6 kernel
> > is ready.
> >
> > Incidently, IDE devices masquerading as SCSI is not as unusual as it
> > might first appear - ATAPI is basically a way to send SCSI commands
> > over the IDE bus.
> >
> > John.
> > -
> > To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.linux-learn.org/faqs
> --
> Regards,
>
> Bryan Simmons
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>
>  On Integrity:
>
>  "I'm going to be as good as they let me and
>   as mean as they make me, and they all know
>   that.  I don't ever lie. If I tell you a
>   rooster can fly, get the harness."
>
>    --Burl Cain, Louisiana State Pen Warden
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.linux-learn.org/faqs
>

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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

Actually, yes.  I believe that JFS, XFS and ReiserFS all use B+ trees to
manage files in a directory.


On Fri, 2002-10-25 at 04:42, Jude DaShiell wrote:
> Do any of the Linux file systems use a tree rather than linked lists?
> 
> 
> 
> On 24 Oct 2002, Bryan Simmons wrote:
> 
> > Shows how much I know about basic system design...
> >
> > In fact, I was shocked to learn last night that ext2 uses linked lists
> > to keep track of files in a directory.  Why is this?  Did the guys who
> > wrote the file system specs go to school for computer science?  I can't
> > tell you how many times my cmsc professors have told us that the linked
> > list is totally inferior to the tree.  At least, it is when it comes to
> > large sets of data.  Perhaps the ext2 guys never saw the need for
> > extremely large sets of files in a single directory, but still, even
> > when hashing, it is suggested that you not handle collisions with linked
> > lists...
> > Stacks and queues are one thing (when used for temporary operations,
> > like iterators and memory management).  But persistent data is another.
> > I would never want to store stuff in a list if it is always going to be
> > accessed, growing and shrinking...
> >
> > On Thu, 2002-10-24 at 07:11, jbradford@dial.pipex.com wrote:
> > > > > Does anyone know a way around this?  I can't hardly believe that all the
> > > > > millions of Linux users have been, and still are, stuck with CD-RWs that
> > > > > have to masquerade as SCSI devices.
> > > >
> > > > There is no way around it, simply read the proper documentation, in this case
> > > > the CD-Writing HOWTO.
> > > > IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in
> > > > widows as well.
> > > > If you find a better way you can tell us millions how you did it then.
> > >
> > > There will soon be a better way - Linus himself mentioned using the
> > > standard IDE devices for cd recording, last Tuesday.
> > >
> > > Expect to see cd recording with native IDE devices once the 2.6 kernel
> > > is ready.
> > >
> > > Incidently, IDE devices masquerading as SCSI is not as unusual as it
> > > might first appear - ATAPI is basically a way to send SCSI commands
> > > over the IDE bus.
> > >
> > > John.
> > > -
> > > To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> > > the body of a message to majordomo@vger.kernel.org
> > > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > > Please read the FAQ at http://www.linux-learn.org/faqs
> > --
> > Regards,
> >
> > Bryan Simmons
> > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> >
> >  On Integrity:
> >
> >  "I'm going to be as good as they let me and
> >   as mean as they make me, and they all know
> >   that.  I don't ever lie. If I tell you a
> >   rooster can fly, get the harness."
> >
> >    --Burl Cain, Louisiana State Pen Warden
> > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> >
> > -
> > To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.linux-learn.org/faqs
> >
-- 
Bryan Simmons <bsimmo1@gl.umbc.edu>

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Re: CD-ROM settings and hardware resources...

[Bryan Simmons]

Read the latest edition of Linux Magazine for details...


On Fri, 2002-10-25 at 06:00, Bryan Simmons wrote:
> Actually, yes.  I believe that JFS, XFS and ReiserFS all use B+ trees to
> manage files in a directory.
> 
> 
> On Fri, 2002-10-25 at 04:42, Jude DaShiell wrote:
> > Do any of the Linux file systems use a tree rather than linked lists?
> > 
> > 
> > 
> > On 24 Oct 2002, Bryan Simmons wrote:
> > 
> > > Shows how much I know about basic system design...
> > >
> > > In fact, I was shocked to learn last night that ext2 uses linked lists
> > > to keep track of files in a directory.  Why is this?  Did the guys who
> > > wrote the file system specs go to school for computer science?  I can't
> > > tell you how many times my cmsc professors have told us that the linked
> > > list is totally inferior to the tree.  At least, it is when it comes to
> > > large sets of data.  Perhaps the ext2 guys never saw the need for
> > > extremely large sets of files in a single directory, but still, even
> > > when hashing, it is suggested that you not handle collisions with linked
> > > lists...
> > > Stacks and queues are one thing (when used for temporary operations,
> > > like iterators and memory management).  But persistent data is another.
> > > I would never want to store stuff in a list if it is always going to be
> > > accessed, growing and shrinking...
> > >
> > > On Thu, 2002-10-24 at 07:11, jbradford@dial.pipex.com wrote:
> > > > > > Does anyone know a way around this?  I can't hardly believe that all the
> > > > > > millions of Linux users have been, and still are, stuck with CD-RWs that
> > > > > > have to masquerade as SCSI devices.
> > > > >
> > > > > There is no way around it, simply read the proper documentation, in this case
> > > > > the CD-Writing HOWTO.
> > > > > IDE-ATAPI CD-RW devices only work with SCSI emulation as they only do in
> > > > > widows as well.
> > > > > If you find a better way you can tell us millions how you did it then.
> > > >
> > > > There will soon be a better way - Linus himself mentioned using the
> > > > standard IDE devices for cd recording, last Tuesday.
> > > >
> > > > Expect to see cd recording with native IDE devices once the 2.6 kernel
> > > > is ready.
> > > >
> > > > Incidently, IDE devices masquerading as SCSI is not as unusual as it
> > > > might first appear - ATAPI is basically a way to send SCSI commands
> > > > over the IDE bus.
> > > >
> > > > John.
> > > > -
> > > > To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> > > > the body of a message to majordomo@vger.kernel.org
> > > > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > > > Please read the FAQ at http://www.linux-learn.org/faqs
> > > --
> > > Regards,
> > >
> > > Bryan Simmons
> > > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> > >
> > >  On Integrity:
> > >
> > >  "I'm going to be as good as they let me and
> > >   as mean as they make me, and they all know
> > >   that.  I don't ever lie. If I tell you a
> > >   rooster can fly, get the harness."
> > >
> > >    --Burl Cain, Louisiana State Pen Warden
> > > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> > >
> > > -
> > > To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> > > the body of a message to majordomo@vger.kernel.org
> > > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > > Please read the FAQ at http://www.linux-learn.org/faqs
> > >
> -- 
> Bryan Simmons <bsimmo1@gl.umbc.edu>
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.linux-learn.org/faqs
-- 
Bryan Simmons <bsimmo1@gl.umbc.edu>

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Linux Mount Partitions

[Abhijit Vijay]

Hi All,

I had a query regarding linux mount partitions, which
I was trying to understand. I understand that Linux
mounts certain partitions by default at certain
locations. You have the kernel image which is located
at /boot (?) and the root partition /root mounted at /
But why is it that /dev/cdrom is mounted by default on
/mnt/cdrom? Why not reduce confusion and mount it on
/dev/cdrom itself? Also, what are the other partitions
that are mounted by default and their default
locations?

Thanks in advance,
Regards,
Abhijit.

__________________________________________________
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Y! Web Hosting - Let the expert host your web site
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Re: Linux Mount Partitions

[Paul Furness]

/dev/cdrom is a link to a "device special file" which the system uses to
communicate with the cdrom drive. It is not a directory, so you couldn't
mount something on it.

The device files are (a little like) pointers to hardware. If you start
trying to change them around, you usually end up screwing up the system
in a big way unless you absolutely know what you are doing

As to what is normally mounted where: this varies from one build of unit
to another. Quite often, you have real partitiona mounted under /,
/boot, /usr, and possibly /home.

The reason file systems are mounted where they are is pretty much
historical convention; it is _possible_ to set up a system with
completely different directory structures, but it's pretty rare that
you'd do that because the conventions are well understood by unix /
linux savvy folks, a non-standard setup can take forever to understand,
and you gain nothing by changing it.

I guess it's just the way we all got used to. :)

To find out exactly what you have mounted where on your system there are
a couple of ways. The most complete techie way is to look at the
contents of /etc/fstab (pron "Eff-Ess-Tab", not ""Fstab") which tells
the system what to mount where. 

An easier way is to go to a command prompt and type:

df -k

and you should get a list a bit like this:

Filesystem           1k-blocks      Used Available Use% Mounted on
/dev/hda2             37334192  15128396  20309324  43% /
/dev/hda1               101089      8902     86968  10% /boot
none                    256948         0    256948   0% /dev/shm

"Filesystem" is the thing that's mounted, and the last column tells you
what it's mounted on.

Paul.


On Fri, 2002-10-25 at 14:04, Abhijit Vijay wrote:
> Hi All,
> 
> I had a query regarding linux mount partitions, which
> I was trying to understand. I understand that Linux
> mounts certain partitions by default at certain
> locations. You have the kernel image which is located
> at /boot (?) and the root partition /root mounted at /
> But why is it that /dev/cdrom is mounted by default on
> /mnt/cdrom? Why not reduce confusion and mount it on
> /dev/cdrom itself? Also, what are the other partitions
> that are mounted by default and their default
> locations?
> 
> Thanks in advance,
> Regards,
> Abhijit.
> 
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Paul Furness

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2+2=5 for extremely large values of 2.

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Re: Linux Mount Partitions

[Steven Smith]

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> You have the kernel image which is located
> at /boot (?)
By convention, the partition which contains the kernel image
is mounted on /boot.  The kernel image itself is just an
ordinary file in that partition.

> But why is it that /dev/cdrom is mounted by default on
> /mnt/cdrom? Why not reduce confusion and mount it on
> /dev/cdrom itself?
/dev/cdrom and /mnt/cdrom provide different interfaces to similar,
but not identical, information.  The device file, which will usually
be /dev/cdrom, is intended for low-level access to the CD itself,
with very little translation (e.g. read 10 sectors starting from
sector 5000), whereas /mnt/cdrom provides a nice view of the files
on the CD.

While it would be possible, in principle, to mount the CD drve
on /dev/cdrom and call the device file something else, any program
which doesn't treat CD as filesystems (like, say, a player for
music CDs) would probably stop working.

> Also, what are the other partitions
> that are mounted by default and their default
> locations?
Have a look in /etc/fstab and ``man fstab''.

Various filesystems are mounted by convention automatically.  These
are virtual, and so don't need a backing partition (the kernel makes
the files up when needed).

The only one you really need is /proc, type proc, which contains
various kernel parameters and information on running processes.  If
you don't have this, ps, top, uptime, and plenty of other programs
stop working.

A filesystem of type shm is also usually mounted on later kernels.
For various arcane reasons, it doesn't actually matter where this
one gets mounted, but /var/shm is common.  A few programs assume
that such a filesystem is mounted somewhere, but very few (the only
one which I can immediately think of is cdrecord).

Depending on the distribution, you may also need to mount devfs
on /dev.  This provides a slightly nicer way of translating
between user-accessible device names (e.g. /dev/cdrom) and the
kernel's internal representations, but isn't really necessary.
If you have it, leave it alone, and if you don't, don't bother
setting it up.

Some programs perform better if a tmpfs filesystem is mounted
on /tmp.  Files created on a tmpfs filesystem are only ever stored
in memory, rather than on disk, so should be far faster.  On the
other hand, they get zapped if you reboot.  Unlike the previous three,
tmpfs can be ignored and, in theory, nothing will actually break,
just run a little slower.

Steven Smith,
sos22@cam.ac.uk.

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