Commit Graph

25 Commits

Author SHA1 Message Date
Jeff Dike ce3b642d42 uml: work around host tcsetattr bug
Under the conditions that UML uses it, tcgetattr is guaranteed to return
-EINTR when the console is attached to /dev/ptmx, making generic_console_write
hang because it loops, calling tcgetattr until it succeeds.  This is a host
bug - see http://marc.info/?l=linux-kernel&m=119618990807182&w=2 for the
details.

This patch works around it by blocking SIGIO while the terminal attributes are
being fiddled.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-03 08:13:17 -08:00
Jeff Dike cb8fa61c2b uml: arch/um/drivers formatting
Style fixes for the rest of the drivers.  arch/um/drivers should be pretty
CodingStyle-compliant now.

Except for the ubd driver, which will have to be treated separately.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:09 -07:00
Jeff Dike 8ca842c4b5 uml: remove os_* usage from userspace files
This patch fixes some userspace files which were calling libc through the os_*
wrappers.

It turns out that there was only one user of os_new_tty_pgrp, so it can be
deleted.

There are also some style and whitespace fixes in here.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:06 -07:00
Jeff Dike 6aa802ce6a uml: throw out CHOOSE_MODE
The next stage after removing code which depends on CONFIG_MODE_TT is removing
the CHOOSE_MODE abstraction, which provided both compile-time and run-time
branching to either tt-mode or skas-mode code.

This patch removes choose-mode.h and all inclusions of it, and replaces all
CHOOSE_MODE invocations with the skas branch.  This leaves a number of trivial
functions which will be dealt with in a later patch.

There are some changes in the uaccess and tls support which go somewhat beyond
this and eliminate some of the now-redundant functions.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:05 -07:00
Jeff Dike c59dbcadd5 uml: fix console writing bugs
The previous console cleanup patch switched generic_read and generic_write
from calling os_{read,write}_file to calling read and write directly.  Because
the calling convention is different, they now need to get any error from errno
rather than the return value.  I did this for generic_read, but forgot about
generic_write.

While chasing some output corruption, I noticed that line_write was
unnecessarily calling flush_buffer, and deleted it.  I don't understand why,
but the corruption disappeared.  This is unneeded because there already is a
perfectly good mechanism for finding out when the host output device has some
room to write data - there is an interrupt that comes in when writes can
happen again.  line_write calling flush_buffer seemed to just be an attempt to
opportunistically get some data out to the host.

I also made write_chan short-circuit calling into the host-level code for
zero-length writes.  Calling libc write with a length of zero conflated write
not being able to write anything with asking it not to write anything.  Better
to just cut it off as soon as possible.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:04 -07:00
Jeff Dike e99525f970 uml: console subsystem tidying
This does a lot of cleanup on the UML console system.  This patch should be
entirely non-functional.

The tidying is as follows:
	header cleanups - the includes should be closer to minimal and complete
	all printks now have a severity
	lots of style fixes
	fd_close is restructured a little in order to reduce the nesting
	some functions were calling the os_* wrappers when they can
call libc directly
	port_accept had a unnecessary variable
	it also tested a pid unecessarily before killing it
	some functions were made static
	xterm_free is gone, as it was identical to generic_free

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:04 -07:00
Jeff Dike 8e2d10e1e7 uml: tidy recently-moved code
Now that the generic console operations are in a userspace file, we
can do the following:
	directly call into libc instead of through the os_* wrappers
	eliminate os_window_size since it has only one user

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:04 -07:00
Jeff Dike 89fe64766a uml: move userspace code to userspace file
Move some code from a kernelspace file to a userspace file where it fits
better.  This enables some tidying which is the subject of a later patch.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:04 -07:00
Jeff Dike c43990162f uml: simplify helper stack handling
run_helper and run_helper_thread had arguments which were the same in all
callers.  run_helper's stack_out was always NULL and run_helper_thread's
stack_order was always 0.  These are now gone, and the constants folded
into the code.

Also fixed leaks of the helper stack in the AIO and SIGIO code.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:38 -07:00
Jeff Dike 42a359e31a uml: SIGIO support cleanup
Cleanup of the SIGWINCH support.

Some code and comment reformatting.

The stack used for SIGWINCH threads was leaked.  This is now fixed by storing
it with the pid and other information, and freeing it when the thread is
killed.

If something goes wrong with a WIGWINCH thread, and this is discovered in the
interrupt handler, the winch record would leak.  It is now freed, except that
the IRQ isn't freed.  This is hard to do from interrupt context.  This has the
side-effect that the IRQ system maintains a reference to the freed structure,
but that shouldn't cause a problem since the descriptor is disabled.

register_winch_irq is now much better about cleaning up after an
initialization failure.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:38 -07:00
Eduard-Gabriel Munteanu 89df6bfc04 uml: DEBUG_SHIRQ fixes
DEBUG_SHIRQ generates spurious interrupts, triggering handlers such as
mconsole_interrupt() or line_interrupt().  They expect data to be available to
be read from their sockets/pipes, but in the case of spurious interrupts, the
host didn't actually send anything, so UML hangs in read() and friends.
Setting those fd's as O_NONBLOCK makes DEBUG_SHIRQ-enabled UML kernels boot
and run correctly.

Signed-off-by: Eduard-Gabriel Munteanu <maxdamage@aladin.ro>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:38 -07:00
Jeff Dike a6ea4cceed uml: rename os_{read_write}_file_k back to os_{read_write}_file
Rename os_{read_write}_file_k back to os_{read_write}_file, delete
the originals and their bogus infrastructure, and fix all the callers.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:03 -07:00
Jeff Dike dc764e5087 uml: formatting fixes around os_{read_write}_file callers
Formatting fixes ahead of renaming os_{read_write}_file_k to
os_{read_write}_file and fixing all the callers.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:03 -07:00
Jeff Dike 3d564047a5 uml: start fixing os_read_file and os_write_file
This patch starts the removal of a very old, very broken piece of code.  This
stems from the problem of passing a userspace buffer into read() or write() on
the host.  If that buffer had not yet been faulted in, read and write will
return -EFAULT.

To avoid this problem, the solution was to fault the buffer in before the
system call by touching the pages that hold the buffer by doing a copy-user of
a byte to each page.  This is obviously bogus, but it does usually work, in tt
mode, since the kernel and process are in the same address space and userspace
addresses can be accessed directly in the kernel.

In skas mode, where the kernel and process are in separate address spaces, it
is completely bogus because the userspace address, which is invalid in the
kernel, is passed into the system call instead of the corresponding physical
address, which would be valid.  Here, it appears that this code, on every host
read() or write(), tries to fault in a random process page.  This doesn't seem
to cause any correctness problems, but there is a performance impact.  This
patch, and the ones following, result in a 10-15% performance gain on a kernel
build.

This code can't be immediately tossed out because when it is, you can't log
in.  Apparently, there is some code in the console driver which depends on
this somehow.

However, we can start removing it by switching the code which does I/O using
kernel addresses to using plain read() and write().  This patch introduces
os_read_file_k and os_write_file_k for use with kernel buffers and converts
all call locations which use obvious kernel buffers to use them.  These
include I/O using buffers which are local variables which are on the stack or
kmalloc-ed.  Later patches will handle the less obvious cases, followed by a
mass conversion back to the original interface.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:03 -07:00
Jeff Dike 9218b17149 uml: remove user_util.h
user_util.h isn't needed any more, so delete it and remove all includes of it.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:01 -07:00
Andrew Morton b16895b63c uml-driver-formatting-fixes-fix
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:00 -07:00
Jeff Dike 56bd194bb2 uml: driver formatting fixes
Fix a bunch of formatting violations in the drivers:
	return(n) -> return n
	whitespace fixes
	emacs formatting comment removal
	breaking if(foo) return(n) into two lines

There are also a couple of errno use bugs:
	using errno in a printk when the failure put errno into a local variable
	saving errno after a printk, which can change it

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:13:00 -07:00
Jan Engelhardt 03a67a46af Fix typos in doc and comments
Changes persistant -> persistent. www.dictionary.com does not know
persistant (with an A), but should it be one of those things you can
spell in more than one correct way, let me know.

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-11-30 05:32:19 +01:00
Jeff Dike 1d2ddcfb19 [PATCH] uml: close TUN/TAP file descriptors
When UML opens a TUN/TAP device, the file descriptor could be copied into
later, long-lived threads, holding the device open even after the interface is
taken down, preventing it from being brought up again.  This patch makes these
descriptors close-on-exec so that they disappear from helper processes, and
adds CLONE_FILES to a UML helper thread so that the descriptors are closed in
the thread when they are closed elsewhere in UML.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-07 16:12:32 -08:00
Paolo 'Blaisorblade' Giarrusso 55c033c1f6 [PATCH] uml console channels: fix the API of console_write
Since the 4th param is unused, remove it altogether.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:14 -08:00
Jeff Dike ff5c6ff542 [PATCH] uml: separate libc-dependent helper code
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from helper.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:31 -08:00
Bodo Stroesser ed1b58d8b5 [PATCH] uml: fix SIGWINCH handler race while waiting for signals.
If a SIGWINCH comes in, while winch_thread() isn't waiting in wait(),
winch_thread could miss signals.  It isn't very probable, that anyone will
see this causing trouble, as it would need a very special timing, that a
missed SIGWINCH results in a wrong window size.

So, this is a minor problem.  But why not fix, as it can be done so easy?

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:21 -07:00
Jeff Dike 1f96ddb4fb [PATCH] uml: clean up error path
This cleans an error path which used to leak file descriptors by returning
without trying to tidy up.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-08 16:21:12 -07:00
Jeff Dike da00d9a546 [PATCH] uml: compile fixes for gcc 4
This is a bunch of compile fixes provoked by building UML with gcc 4.  There
are a bunch of signedness mismatches, a couple of uninitialized references,
and a botched C99 structure initialization which had somehow gone unnoticed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-08 16:21:12 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00