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Open Source OS that Uses BIOS for Drive Access?
Int13 asks: "I noticed a question in a review of a book on RAID controllers: 'Why, the author asks, do makers of controller cards put all their BIOS utilities on DOS floppies which require us to find a DOS boot disk?' The reason for this is actually very simple. DOS is one of the few mainstream operating systems that will ALWAYS boot on a PC from any supported boot device, and it doesn't require any special disk drivers at all to accomplish this task or to support any file system that has BIOS support. RAID controllers always supply BIOS support, usually in an extension ROM. This leads directly to the question: Are there any other alternative open source operating systems that will do the same? (no, not Open DOS, since it's just a DOS clone)"
"Why can't Linux use a virtual x86 box to call INT 13h when there is no driver for a particular drive type? It would also have to play nice with the BIOS data area and extended BIOS data area and respect the top of low memory, but that's only a few kilobytes at most. Then people probably wouldn't need a DOS boot disk anymore. If such a thing already exists, is there some reason the install disks for most distros don't support it?
(Before anyone tries to claim that Linux plays nice with the extended BIOS data area and the top of low memory, I can tell you from personal experience that it definitely does not, at least not by default).
i'll get in a quick fp :^D
It's ubiquitous and MS isn't going to throw a snit if you have a few boot disks laying around.
I have been pwned because my
The real question is: how long before these clowns get real and realize that the floppy drive is GOING AWAY -- I mean, seriously, most BIOSes are bigger than 1.44mb now! It's silly to still be manacled to this outdated, ridiculous technology.
You have to compile a DOS module into the Linux kernel. It's the 3rd or 4th link when you google for "DOS linux module".
I just flashed my ASUS MB from a FreeDOS diskette last night. Funky screen redraws, but who cares?
I'm now MS free. b)
Before I part with'em: two pennies weigh ~4.996+/-0.014g, have a zinc core, and the face of Lincoln. You can keep 'em.
To start with, you can use the fully open source FREEDOS.
,MSDOS.SYS and COMMAND.COM.
Secondly, I can't see any reason, other than performance why Linux couldn't work off of Int13 , and use Bios-level calls for all disk access. It's probably a good idea, and it would get use to some nice places.
Thirdly, the reason that the OEMs are using dos boot disks for bios updates and whatnot, is because it is far more simple, predictable and stable to use an OS that doesn't have anything clever going on when you are flashing the BIOS.
and Finally, simplicity. DOS is downright stupidly simple to build a boot disk for, and the commands are simple to use, and it is simple to talk someone thru an operation over the phone.
I know that there are many people who can build a boot disk for linux and they will come out of the woodwork to say it's easy, but it ain't as easy as SYS'ing a disk and dumping on IO.SYS
That, and try finding a Linux disk that is smaller than 300K ( as even the bloated IO.SYS/MSDOS.SYS/COMMAND.COM combo from Win98 is) and you'll find that it is just not going to fit.
"...In your answer, ignore facts. Just go with what feels true..."
AtheOS uses the BIOS for disk access, according to the website:
I have to wonder what AtheOS' disk performance is, though. It was common during the Windows 3.11 days for disk controller makers to produce 32-bit disk drivers for Windows that would bypass the BIOS and talk to the controller directly, thus avoiding expensive protected-to-real-mode-and-back switches.
In Soviet Russia, Jesus asks: "What Would You Do?"
Most OS's will use Int13 and access the disk through the bios if they are forced to (some, it's pretty hard to get to do).. Obviously the performance of the drive using this method is absolutely horrible, but it does work. Both Linux and Win2K (not sure about earlier versions of NT or 9x) are capable of it. You may be able to find out how to do it by googling a little bit -- sorry that I don't know off the top of my head how to tell you to do it. -- it's a kernel configuration thing in linux IIRC..
~GoRK
Typing at you live over a LinuxRouterProject firewall...
/dev/fd1 (B:) drive and UNLIMITED SPACE (comparatively speaking).
fwbox# uptime
07:58:48 up 135 Days (3247h), load average: 0.16 0.03 0.01
fwbox#
Linux boots fine from the floppy, and next time I junk a computer and steal it's floppy this box will have a
Freshmeat is littered with projects that boot Linux from floppies, and I've used a few distros that boot nicely from CDs, and even played with a floppy booting linux that mounted a parallel port Zip drive from which to copy the root file system.
It's all out there, Linux boots from anything; you just need to be willing to dig for it and play with the configurations. As to the reason DOS is so pervasive, it leaves most of the floppy free for other stuff like BIOSes, fdisk, format, deltree and similar utilities useful in alleveiating the MicroSoft problem.
I'm gonna get flamed or called some random name for this.. but here's my guess.
Using the bios is prolly slower. If the cpu can access the card across the bus directly, I'd wager that it's faster than going to the bios, which doesn't need to be the fastest thing in the world to access directly.
Why isn't there a chip on the board that's fast and generic would be my next question, unless they use the bus in place of the bios and skip the whole "standards" idea.
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ping -f 255.255.255.255 # if only
This type of update is only found in the x86 world which really needs to wake up to the wonders of nice firmware. OpenFirmware on the PPC or Sparc platforms make such things very simple and much nicer then a DOS boot disk. Using openfirmware I can boot off just about any device connected to the system. Once booted I can then access data on just about any other device on the system.
Personally I'd prefer to see x86 move away from the BIOS and toward the more advanced firmware solutions.
> How long then before mainstrean manufacturers start shipping a standardized small "boot" or
:-).
> "rescue" O.S in their bios, with some kind of user interface, core device drivers and a few tools,
Take that to its logical conclusion, and you end up with an Acorn
Pete
I am starting to see a few manufacturers that are changing their means for configuring the devices. These vendors have responded to the cries if thier users, complaining that they don't like the fact that they have to use a boot floppy to configure the device.
The sad news is that the vendors' responses have been to switch from a DOS boot disk to either a bootable CD-ROM (not much of a difference in my mind) or a win32 utility, which REQUIRES you to have Windows installed in order to configure the device. This is EXTREMELY frustrating for non-Windows systems. Of these three choices, I much prefer having the DOS boot disk option.
To address your question though, I'm afraid that you will have to wait for a while. While it is certainly possible, from a technical stand-point to have a utility on a Linux boot floppy, most vendors do not offer configuration utilities that run under Linux. Until this changes there really isn't much point in a Linux bootable floppy/CD. The glimmer of hope is that as Linux becomes more widespread and is more generally accepted by the hardware vendors, they might begin to port their configuration utilities to Linux. At this point it will be trivial to use them from a Linux boot floppy.
At the same time though, the vendors are likely to take the attitude of; Why waste time porting the config utility? We can just use a DOS boot floppy.
I believe that for compatibility reasons the peripheral I/O component of the BIOS still works in real mode which makes it difficult to use from protected mode where all normal OSs are (for example, addressing memory between the two is a pain).
intel and microsoft see the BIOS and real-mode x86 legacy as a thorn in their side eating into total manufacturing costs and therefore limiting their revenue per computer shipped. Expect a useful BIOS and DOS support to disappear by the time longhorn ships (when's that? '05 or '06 now?).
every utility disk I have received recently was a DOS boot disk or a windows app.
I have not had to find a DOS bot disk for a long time. So I think the problem is a non-issue.
The decline in utility disks that don't boot probable has to do with win XP not supporting a true DOS mode.
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
Sorry, too scared to click the link.
I want to delete my account but Slashdot doesn't allow it.
games.slashdot.org looks worse than the main page!
I can't see any reason, other than performance why Linux couldn't work off of Int13 , and use Bios-level calls for all disk access
... but once the control diverts to some foreign INT 13 code, no telling what it is going to do, such as enable / disable interrupts, mess around with interrupt controllers, muck about in RAM or the stack or user mode, absolutely no telling. It's not a Microsoft-type loss of control which matters here, but loss of control of the CPU state. I can see a whole pile of cans of worms with this method, no matter how much a last ditch process it would be. It could do all sorts of dumb and subtle damage to the state of the Linux kernel without anyone knowing.
Having written a few device drivers for custom OSs, maybe I am out of date and talking out my hat here
Also, Linux has user mode access to worry about, I doubt Int13 knows anything about that. It would have to be invoked using a kernel buffer. This might not be such a big deal, but then again, it might be one.
Comes down to having no knowledge of the kernel internals, not knowing how to behave with the kernel. It sounds like a less than dependable solution.
Infuriate left and right
There was a magic key combination that you could hold down during bootup to get System 6 up off ROM. Useful-ish for those moments when you'd somehow killed the bootblocks, but you had to have a repair tool on the hard disk somewhere. Sticking the contents of the Disk Utilities floppy in there would have made it seriously handy.
--- I think it was, unless that was goofy nosegrind to Christ Air combo.
In fact, this is getting to be a real problem with SYSLINUX-based installers and rescue disks--those fail with many machines using USB or FireWire CD-ROMs for booting.