Linux-Development-Sys Digest #697, Volume #7 Wed, 22 Mar 00 21:13:21 EST
Contents:
Re: Implicit declarations... (David A. Mair)
Re: UART overrun errors (Johan Kullstam)
CD-ROM API Question (Steffen Sobiech)
Re: Problem getting mmap region to work correctly.... Please help... (Joe Pfeiffer)
Re: Protocol Implementation (Andi Kleen)
Re: User process virtual memory layout (Andi Kleen)
Re: what do i wrong with skb_copy()? (Andi Kleen)
Re: poll()ing TCP sockets - when can I expect a POLLHUP? (Andi Kleen)
Re: =?iso-8859-1?Q?=EE=D5=D6=CE=C1=20=D0=CF=CD=CF=DD=D8=21=21=21?= ("Robert M.
Stockmann")
Embedded Systems Development ("Accutrol")
2.3.99: what's next step? ("Giampaolo Tomassoni")
Re: Is there a way to boot linux off a Server (another linux box) containing a
proper image
Re: what do i wrong with skb_copy()? (Kaz Kylheku)
Re: 2.3.99: what's next step? ("Arthur H. Gold")
Re: [embedded linux] where to get related information? ("tim")
Re: Gonna build a computer... (Ron Reeder)
Re: device driver database? (Ron Reeder)
Re: Absolute failure of Linux dead ahead? (Christopher Browne)
Job posting: HP-Lab (Zheng Zhang)
----------------------------------------------------------------------------
From: David A. Mair <[EMAIL PROTECTED]>
Subject: Re: Implicit declarations...
Date: Wed, 22 Mar 2000 13:27:39 -0700
On Tue, 21 Mar 2000 22:03:26 +0100, Fabrice Peix
<[EMAIL PROTECTED]> wrote:
>"David A. Mair" wrote:
>>
>> I admit I am an utter novice when it comes to system programming for
>> Linux, but I have more than ten years of system programming experience
>> ...
>> possible causes, but figure that would only result in my showing more
>> naivity of the platform and compiler.
>you must include <linux/kernel.h>
The code had that from the start, it isn't the problem (had it been
that basic I would have found the cause, but thanks for the
suggestion). The problem was that the sample I started with suggested
I conditionally include modversions.h. I commented that out and the
warnings vanished, thanks to Nilesh for the answer there.
>
>>
>> My second problem is more platform related. In a kernel module I can
>>....
>> would suffice).
>Linux Driver Modules Alexandro Rubinni
>
Thanks, I'll look it up.
>>
>> Thanks for any and all help.
>>
>> Regards,
>> David.
======================================================
In order to avoid the harassment of spam I have
deliberately included an invalid e-mail address in
this message. To contact me by mail remove the not.
after the @ symbol in the enclosed e-mail address. You
should note that due to the quantity of mail I receive
I may not answer and I am more likely to respond to
follow-up messages.
======================================================
------------------------------
From: Johan Kullstam <[EMAIL PROTECTED]>
Subject: Re: UART overrun errors
Date: 22 Mar 2000 15:43:55 -0500
[EMAIL PROTECTED] (Tony R. Bennett) writes:
> In article <[EMAIL PROTECTED]>,
> Mats Byggmastar <[EMAIL PROTECTED]> wrote:
> >Hello,
> >
> >I'm working with some serial port code and (again) run into problems.
> >I open a port (/dev/ttyS0) at 115200 bps. Data is sent/received over
> >the port at a steady 64 kbit/s. I've also tried using lower speeds.
> >However, the port don't seem to be very reliable. As soon as there is
> >some disk activity, I immediately receive errors in my data stream.
> >Either bytes are lost or random bytes are inserted into the received data
> >stream. Checking in /proc/tty/driver/serial I see that a 16550A UART is
> >used. I can also see that the errors are registered as overrrun errors.
> >
> >Does this mean that the interrupt that the 16550A issues isn't served by
> >the driver in time and the FIFO gets overwritten?
> >
> >To eliminate the possibility that I could be picking up external noise
> >on the null-modem cable I tested the port in loopback, TX pin connected
> >to RX pin, with a very short wire. The problem was still there.
> >
> >Anyone has some ideas what is going on?
> >
> >I am using Red Hat 6.1
> >
> >
> >Mats
> >-------------------------------------------
> >Mats Byggmastar, B.Sc., SW Design Engineer
> >GSM/GPRS/D-AMPS cellular data testequipment
> >Moesarc Technology AS, Oslo Norway
> >[EMAIL PROTECTED], tel: (+47)22516974
>
>
> First let me preface this with "I'M NOT AN EXPERT"
>
> A couple of things:
>
> - the UART generates an interrupt when data is ready...
> (Possibly, when there are certain number of bytes in
> its FIFO buffer)...the OS prioritizes the interrupts
> so a DISK interrupt may have priority over a serial port
> interrupt... but we can't control that...
oh yes we can. irqtune.
--
johan kullstam l72t00052
------------------------------
From: Steffen Sobiech <[EMAIL PROTECTED]>
Subject: CD-ROM API Question
Date: Wed, 22 Mar 2000 22:01:23 +0100
Hi there!
Is there any way to find out the tray position
of my IDE-CDROM?
I am using Kernel 2.2.12 .
Using CDROM_DRIVE_STATUS correctly returns that
a disc is inserted, but it does not distinguish
between TRAY_OPEN and NO_DISC. It always returns
TRAY_OPEN even if it is closed (with no disc in it).
Any suggestions?
------------------------------
From: Joe Pfeiffer <[EMAIL PROTECTED]>
Subject: Re: Problem getting mmap region to work correctly.... Please help...
Date: 22 Mar 2000 15:15:55 -0700
Robert Nickel <[EMAIL PROTECTED]> writes:
> I'm trying to write a user space loader program that loads control rom from a disk
>file into volatile rom on the card. This is done via i/o ports and the memory range
>from 0xd0000-0xd7fff.
>
> The i/o ports part was really simple and I've got it under control. The part that's
>keeping me up nights is the mmap portion. I can't get it to work for me, and I'm
>curious as to why.
>
> The card is supposed to switch 16k banks of the memory to and from the beginning of
>the memory range. The problem I'm having is that the banks aren't switching. I'm
>wondering if it is the MAP_PRIVATE flag in my call to mmap.
>
> Here's my code, boiled down to the part that is giving me grief:
>
> --------------------------------------------------
>
> //The variables in question are defined as follows
> unsigned char *cardmem;
> int memptr;
>
> if ((memptr=open("/dev/mem", O_RDWR))<0) {
> choke_and_die("Couldn't get memory"); //My death function
> exit(1);
> }
>
> if ((cardmem=(unsigned char *)
>mmap(0,0x7fff,PROT_READ|PROT_WRITE,MAP_PRIVATE,0xd0000))<0) {
> choke_and_die("Couldn't map memory");
> exit(1);
> }
I think you must have done more boiling down than you think: you want
to map 0x8000 bytes (that's a length field, and must be divisible by
the page size), and presumably you meant actually pass the file descriptor.
Regardless, that MAP_PRIVATE could easily be the problem -- that makes
the pages you map copy-on-write, so when you try to write to them the
system makes you a fresh copy and all your writes go to the new one.
--
Joseph J. Pfeiffer, Jr., Ph.D. Phone -- (505) 646-1605
Department of Computer Science FAX -- (505) 646-1002
New Mexico State University http://www.cs.nmsu.edu/~pfeiffer
VL 2000 Homepage: http://www.cs.orst.edu/~burnett/vl2000/
------------------------------
From: Andi Kleen <[EMAIL PROTECTED]>
Subject: Re: Protocol Implementation
Date: 23 Mar 2000 00:27:41 +0100
[EMAIL PROTECTED] writes:
> Hello,
>
> On Linux how do we implement a new protocol which is required to work in
> parallel to other protocols eg TCP/IP etc.This protocol is to be
> implemented just above the ethernet MAC layer.
man packet(7)
-Andi
------------------------------
From: Andi Kleen <[EMAIL PROTECTED]>
Crossposted-To: comp.unix.programmer
Subject: Re: User process virtual memory layout
Date: 23 Mar 2000 00:34:33 +0100
[EMAIL PROTECTED] (Sean R. Manning) writes:
> Thanks for the tip. The results of your print out illustrate the
> other part of my question. Specifically, they show that the .text
> area of the netscape process are located at 0x08048000-0x08b03000. As
> you pointed out, the .text (program code) is loaded first in the lower
> memory address. However, why would it not be loaded starting at
> 0x00000000? Or at least somewhere much lower than 0x08048000.
> Thanks.
0 - 0x8000000 is the kernel space. This can be changed with the
CONFIG_1/2GB kernel options in later 2.2, because all physical
memory has to fit into the kernel mapping (2.3+ discourages this
and uses BIGMEM/HIGHMEM instead to map only part of the physical
memory at a time)
-Andi
------------------------------
From: Andi Kleen <[EMAIL PROTECTED]>
Subject: Re: what do i wrong with skb_copy()?
Date: 23 Mar 2000 00:37:01 +0100
root <[EMAIL PROTECTED]> writes:
>
> static int sndcp_tx(struct sk_buff *skb, struct device *dev)
> {
> int ret;
> struct sk_buff *skb2;
>
> skb2 = skb_copy(skb, GFP_ATOMIC);
> ret = boomerang_start_xmit(skb2, dev);
> dev_kfree_skb(skb2);
^^^^^^^^^^^^^^^^^^^
This is wrong, because the low level driver is supposed to do the
kfree_skb (because it often has its own queue).
-Andi
------------------------------
From: Andi Kleen <[EMAIL PROTECTED]>
Crossposted-To: comp.unix.programmer
Subject: Re: poll()ing TCP sockets - when can I expect a POLLHUP?
Date: 23 Mar 2000 00:48:05 +0100
[EMAIL PROTECTED] (Casper H.S. Dik - Network Security Engineer) writes:
>
> >Having experimented I see:
>
> >Linux 2.2.5 fails to set POLLIN but sets POLLHUP.
>
> Bug.
Single Unix does not require it:
POLLIN
Data other than high-priority data may be read without
blocking. For STREAMS, this flag is set in revents even if the
message is of zero length.
Linux does not use STREAMS, so the zero length rule does not apply.
Linux only sends a pure POLLHUP when there is no data to read
and the local end was shut down.
Setting POLLIN to signal errors is clearly a select(2)ism cause
by its limited interface; poll should be able to do better.
>
> >My questions:
> >(1) what _should_ poll() be doing?
>
> If it sets POLLHUP on a TCP stream, it should only do so if it
> has half-closed its end (w/ shutdown) or if a RST was received
> after a write.
Linux does that (half closed or full closed on the local end)
-Andi
------------------------------
From: "Robert M. Stockmann" <[EMAIL PROTECTED]>
Subject: Re: =?iso-8859-1?Q?=EE=D5=D6=CE=C1=20=D0=CF=CD=CF=DD=D8=21=21=21?=
Date: Thu, 23 Mar 2000 00:27:41 +0100
Vladimir Vizgalin wrote:
>
> ������ �����!!!!
> � ���� �������� �������� - ���� ���������� � Linux ��� ����������� ��������
> �������. ������ �������� ��� ����� �������. ��� ����� �������� api �������
> ������, �������� ������ �������, ������ ������� � �.�.
>
> ������� ����������.
>
> ��������.
oeww yes, my terminal goes cyrillic .
--
++---------------------++---------------------------------++
|| R.M. Stockmann || InfoMagic Nederland VOF ||
|| [EMAIL PROTECTED] || Unix administration & support ||
++---------------------++---------------------------------++
Linux: A copylefted Unix-like operating system for several platforms :
http://perso.wanadoo.es/xose/linux/linux_ports.html
------------------------------
From: "Accutrol" <[EMAIL PROTECTED]>
Subject: Embedded Systems Development
Date: Wed, 22 Mar 2000 23:32:13 GMT
I am sitting on the fence looking at the choices of operating systems
available for embedded systems development. I write software for direct
machine control and operator interfaces (mostly keyboard input and
alphanumeric displays for embedded systems, will address GUI later). Some
of the development has been for Windows 95/98 and other for Windows NT, but
most has been for ROM-DOS using QuickBasic (Microsoft).
I have been interested in development of Windows CE for the industrial
computing market and haven't seen enough to interest me, yet. The main
issues that I'm concerned about are shoe-horning the OS onto an SBC and I/O
driver availability. (I'm not an OS developer!)
I have recently considered Linux as an option and would like to explore the
possibilities. The thing I am concerned about here is driver availability
for commercial off-the-shelf (COTS) I/O hardware, e.g., digital I/O, analog
I/O, RS-232, and display device support. I am aware that Lineo (Caldera) is
developing an embedded version of Linux that might fit my needs, but I'd
like to at least get started with something fairly soon.
I have used UNIX fairly extensively and have even developed analytical code
using GNU S/W development tools (gcc and g77) in the past (10 years ago) and
was fairly pleased with them then.
I have searched several internet and news sites looking for anything to do
with driver availability for COTS I/O hardware and have found none.
I'm not a Bill basher, although the FSF matches my goals more closely. I
know, I'm opening up for a lot of comment here, but please, let's keep to
the subject at hand. Does anyone know of a site that maintains links to
information that might help me make an informed decision? BTW, I'm not
exactly on the fence; I'm leaning toward Linux. I just need a little
encouragement.
Thanks,
Hamilton Woods
[EMAIL PROTECTED]
------------------------------
From: "Giampaolo Tomassoni" <[EMAIL PROTECTED]>
Subject: 2.3.99: what's next step?
Date: Thu, 23 Mar 2000 00:22:47 +0100
Does it mean we are close to get a linux 2.4.0 kernel?
Thanks,
Giampaolo
------------------------------
From: [EMAIL PROTECTED] ()
Subject: Re: Is there a way to boot linux off a Server (another linux box) containing
a proper image
Date: 22 Mar 2000 23:43:25 GMT
Reply-To: [EMAIL PROTECTED]
"Wai Wu" <[EMAIL PROTECTED]> writes:
|>
|>
|>
have a look at http://www.slug.org.au/etherboot
--
Chris Willing Ph: (61-2) 9351 3005
Vislab, A28 Fax: (61-2) 9351 7726
University of Sydney Email: [EMAIL PROTECTED]
NSW 2006 Australia http://www.vislab.usyd.edu.au/staff/chris/
------------------------------
From: [EMAIL PROTECTED] (Kaz Kylheku)
Subject: Re: what do i wrong with skb_copy()?
Reply-To: [EMAIL PROTECTED]
Date: Thu, 23 Mar 2000 00:01:12 GMT
On 23 Mar 2000 00:37:01 +0100, Andi Kleen <[EMAIL PROTECTED]> wrote:
>root <[EMAIL PROTECTED]> writes:
>
>>
>> static int sndcp_tx(struct sk_buff *skb, struct device *dev)
>> {
>> int ret;
>> struct sk_buff *skb2;
>>
>> skb2 = skb_copy(skb, GFP_ATOMIC);
>> ret = boomerang_start_xmit(skb2, dev);
>> dev_kfree_skb(skb2);
> ^^^^^^^^^^^^^^^^^^^
>This is wrong, because the low level driver is supposed to do the
>kfree_skb (because it often has its own queue).
All drivers have an effective queue of at least one buffer, by hanging on to
the buffer until they are done sending it.
If the driver is not able to take the packet because it is currently busy, it
still calls dev_kfree_skb() on it.
--
#exclude <windows.h>
------------------------------
Date: Wed, 22 Mar 2000 18:35:09 +0000
From: "Arthur H. Gold" <[EMAIL PROTECTED]>
Subject: Re: 2.3.99: what's next step?
Giampaolo Tomassoni wrote:
>
> Does it mean we are close to get a linux 2.4.0 kernel?
>
> Thanks,
>
> Giampaolo
Well, it's probably _pretty_ close, but IIRC the 2.1 series went up to
2.1.131 (which is not to say the 2.3's will necessarily go that high).
HTH,
--ag
--
Artie Gold, Austin, TX (finger the cs.utexas.edu account for more info)
mailto:[EMAIL PROTECTED] or mailto:[EMAIL PROTECTED]
--
A: Look for a lawyer who speaks Aramaic...about trademark infringement.
------------------------------
From: "tim" <[EMAIL PROTECTED]>
Subject: Re: [embedded linux] where to get related information?
Date: Thu, 23 Mar 2000 08:46:51 +0800
Reply-To: "tim" <[EMAIL PROTECTED]>
Russell King's web pages http://www.arm.linux.org.uk/ are the "official"
home of the Linux/ARM port. u can find some embedded development there.
tasi <[EMAIL PROTECTED]> wrote in message
news:8b71o9$jiv$[EMAIL PROTECTED]...
> Dear All
>
> I look for a embedded linux base on x86 or ARM target.
> Could somebody tell me the success story about
> (1) what target(Evaluate board) does you use? price? how to get the
> information?
> (2) where to get the embedded linux ?
> Thanks!!
>
> mail to [EMAIL PROTECTED]
>
>
>
------------------------------
From: Ron Reeder <[EMAIL PROTECTED]>
Subject: Re: Gonna build a computer...
Date: Wed, 22 Mar 2000 18:12:18 -0700
Patrick Hagerty wrote:
>
> Kaz,
> What's "RTFM", if you don't mind.
>
> Patrick
You probably don't want to be reading a development NG.
RTFM == Read The F'ing Manual
One of the earliest Computer Acronyms - Dates at least back to the 70's.
When people ask questions that are answered in a FAQ
(Frequently Asked Question - Written compilation of such)
or other obvious documentation... People often give a one line
admonition... and if they are polite, pointer to that documentation.
--
+-------------------------------+-------------------------------+
| Ron Reeder | [EMAIL PROTECTED] |
| Denver Technical Support | Phone: (303) 389-4408 |
| Western Geophysical Company | Fax: (303) 595-0667 |
+-------------------------------+-------------------------------+
------------------------------
From: Ron Reeder <[EMAIL PROTECTED]>
Subject: Re: device driver database?
Date: Wed, 22 Mar 2000 18:16:00 -0700
Shawn Halwes wrote:
>
> Where does one go to find a list of device drivers for Linux?
>
> Thanks,
> Shawn
/usr/src/drivers
At least on RH dist'n
--
+-------------------------------+-------------------------------+
| Ron Reeder | [EMAIL PROTECTED] |
| Denver Technical Support | Phone: (303) 389-4408 |
| Western Geophysical Company | Fax: (303) 595-0667 |
+-------------------------------+-------------------------------+
------------------------------
From: [EMAIL PROTECTED] (Christopher Browne)
Crossposted-To: comp.os.linux.advocacy
Subject: Re: Absolute failure of Linux dead ahead?
Reply-To: [EMAIL PROTECTED]
Date: Thu, 23 Mar 2000 01:19:05 GMT
Centuries ago, Nostradamus foresaw a time when Ronald Cole would say:
>[EMAIL PROTECTED] (The Ghost In The Machine) writes:
>> Would you rather we rewrite the kernel in Fortran or COBOL? :-)
>
>What's wrong with Modula-3? ;)
Nothing in particular.
Of course, it wouldn't make sense to *merely* rewrite it in Modula-3;
it would make *more* sense to do some redesign to take advantage of
the functionality Modula-3 offers.
It's an interesting idea; some of the people that waste time
blathering about redoing Linux in C++ should take a look at the M3
option, and consider actually starting a project rather than merely
blathering about it...
--
I think you ought to know I'm feeling very depressed
[EMAIL PROTECTED] <http://www.ntlug.org/~cbbrowne/languages.html>
------------------------------
From: Zheng Zhang <[EMAIL PROTECTED]>
Crossposted-To: comp.protocols.nfs,alt.filesystems.afs
Subject: Job posting: HP-Lab
Date: Wed, 22 Mar 2000 18:02:05 -0800
Hi,
We are looking for a researcher to join a challenging project of
distributed file system.
Please contact:
Zheng Zhang
[EMAIL PROTECTED]
(650)857-7195(O)
if you are interested. Pleaes help to distribute this, much thanx!
Regards,
========================================================================
Essential Responsibilities:
The Distributed Storage Service project within Platform System Software
Department of HP-Lab is charted to research and develop a highly scalable
file system for next generation Intenet Data Center infrustructure. The
architecture is to leverage the latest Storage-Area-Network (SAN) technology
and other proprietary techniques to derive a high performance, highly
available and yet flexible solution for our target environment.
We are looking for individual with strong research capabilities and
experience in distributed system and/or file systems. In our team-oriented
setting, you will be given the opportunity and responsibility to drive the
design and implementation of significant portion of the architecture.
Marginal Responsibilities:
You will have the opportunity to represent the group and its work
inside and outside of HP, including our product-team partners.
Musts:
PhD, MS with 3+ years, or BS with 5+ years industrial experience in
distributed system or related area. Familiar with OS internals and
file systems. Great implementation skills. Good communication skill
and the ability to work effectively in a small team. Highly motivated
and take great fun in inventing technologies that will make a difference.
Note: your the exact degree is not important, we are looking for
bright individual having hands-on experience and the willingness to
conduct solid research, and contribute to a world-class team.
Desired:
Worked on file systems internals before, understand storage systems.
Familiar with at least of one of the major OS flavors, including
UNIX and NT. Familiar with FreeBSD and/or Linux.
========================================================================
--
Zheng Zhang, ( BambooMan )
Hewlett-Packard Labs. tel: (650) 857-7195
1501 Page Mill Rd., M/S 3U-7 fax: (650) 236-9675
Palo Alto e-mail: [EMAIL PROTECTED]
CA. 94304, USA http://www.hpl.hp.com/personal/Zheng_Zhang
------------------------------
** FOR YOUR REFERENCE **
The service address, to which questions about the list itself and requests
to be added to or deleted from it should be directed, is:
Internet: [EMAIL PROTECTED]
You can send mail to the entire list (and comp.os.linux.development.system) via:
Internet: [EMAIL PROTECTED]
Linux may be obtained via one of these FTP sites:
ftp.funet.fi pub/Linux
tsx-11.mit.edu pub/linux
sunsite.unc.edu pub/Linux
End of Linux-Development-System Digest
******************************
