A number of files that were changed in the recent removal of tt mode
are userspace files which call the os_* wrappers instead of calling
libc directly.  A few other files were affected by this, through

This patch makes these call glibc directly.

There are also style fixes in the affected areas.

os_print_error has no remaining callers, so it is deleted.

There is a interface change to os_set_exec_close, eliminating a
parameter which was always the same.  The callers are fixed as well.

os_process_pc got its error path cleaned up.
Signed-off-by: NJeff Dike <jdike@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NJeff Dike <jdike@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Formatting changes in the files which have been changed in the course
of folding foo_skas functions into their callers.  These include:
	copyright updates
	header file trimming
	style fixes
	adding severity to printks

These changes should be entirely non-functional.
Signed-off-by: NJeff Dike <jdike@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NJeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I found a type mismatch in UML that makes host block devices unusable as ubd
devices on x86_64 and other 64 bits systems (segfault of the mm subsystem):

In block/ioctl.c, the following lines show that the BLKGETSIZE ioctl expects
a pointer to a long:

	case BLKGETSIZE:
		if ((bdev->bd_inode->i_size >> 9) > ~0UL)
			return -EFBIG;
		return put_ulong(arg, bdev->bd_inode->i_size >> 9);

In arch/um/os-Linux/file.c, os_file_size calls it with an int.

The ioctl_list man page should be fixed as well.

Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NJeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NJeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

user_util.h isn't needed any more, so delete it and remove all includes of it.
Signed-off-by: NJeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We shouldn't be using the os wrappers from os code - we can use libc directly.
This patch replaces wrapper calls with libc calls.

It turns out that os_sigio_async had only one caller, which was in startup.c,
so that function is moved there and its name changed.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add some more uses of the CATCH_EINTR wrapper.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix a bunch of formatting problems.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Blairsorblade noticed some confusion between our use of a system
call's return value and errno.  This patch fixes a number of related
bugs -
	using errno instead of a return value
	using a return value instead of errno
	forgetting to negate a error return to get a positive error code
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix an fd leak and a return of -1 instead of -errno in the error path - this
showed up in intensive testing of HPPFS, the os_connect_socket user.
Signed-off-by: NPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The poster child for this patch is the third tuntap_user hunk.  When an ioctl
fails, it properly closes the opened file descriptor and returns.  However,
the close resets errno to 0, and the 'return errno' that follows returns 0
rather than the value that ioctl set.  This caused the caller to believe that
the device open succeeded and had opened file descriptor 0, which caused no
end of interesting behavior.

The rest of this patch is a pass through the UML sources looking for places
where errno could be reset before being passed back out.  A common culprit is
printk, which could call write, being called before errno is returned.

In some cases, where the code ends up being much smaller, I just deleted the
printk.

There was another case where a caller of run_helper looked at errno after a
failure, rather than the return value of run_helper, which was the errno value
that it wanted.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

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: NJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

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!