Commit Graph

296 Commits

Author SHA1 Message Date
Alan Cox 33f0f88f1c [PATCH] TTY layer buffering revamp
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.

This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.

When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.

For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).

Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.

The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.

I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.

Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real.  That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.

Description:

tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification].  It
does now also return the number of chars inserted

There are also

tty_buffer_request_room(tty, len)

which asks for a buffer block of the length requested and returns the space
found.  This improves efficiency with hardware that knows how much to
transfer.

and tty_insert_flip_string_flags(tty, str, flags, len)

to insert a string of characters and flags

For a smart interface the usual code is

    len = tty_request_buffer_room(tty, amount_hardware_says);
    tty_insert_flip_string(tty, buffer_from_card, len);

More description!

At the moment tty buffers are attached directly to the tty.  This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)

I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers.  This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.

So far so good.  Lots of drivers reference tty->flip.*.  Several of them also
call directly and unsafely into function pointers it provides.  This will all
break.  Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.

At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say

 int tty_buffer_request_room(tty, size)

Try and ensure at least size bytes are available, returns actual room (may be
zero).  At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative.  (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space.  The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.

 int tty_insert_flip_char(tty, ch, flag)

As before insert a character if there is room.  Now returns 1 for success, 0
for failure.

 int tty_insert_flip_string(tty, str, len)

Insert a block of non error characters.  Returns the number inserted.

 int tty_prepare_flip_string(tty, strptr, len)

Adjust the buffer to allow len characters to be added.  Returns a buffer
pointer in strptr and the length available.  This allows for hardware that
needs to use functions like insl or mencpy_fromio.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:59 -08:00
Thomas Gleixner becf8b5d00 [PATCH] hrtimer: convert posix timers completely
- convert posix-timers.c to use hrtimers

- remove the now obsolete abslist code

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:39 -08:00
Matt Mackall e585e47031 [PATCH] tiny: Make *[ug]id16 support optional
Configurable 16-bit UID and friends support

This allows turning off the legacy 16 bit UID interfaces on embedded platforms.

   text    data     bss     dec     hex filename
3330172  529036  190556 4049764  3dcb64 vmlinux-baseline
3328268  529040  190556 4047864  3dc3f8 vmlinux

From: Adrian Bunk <bunk@stusta.de>

    UID16 was accidentially disabled for !EMBEDDED.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:11 -08:00
Eric W. Biederman 5e38291d80 [PATCH] Don't attempt to power off if power off is not implemented
The problem.  It is expected that /sbin/halt -p works exactly like
/sbin/halt, when the kernel does not implement power off functionality.

The kernel can do a lot of work in the reboot notifiers and in
device_shutdown before we even get to machine_power_off.  Some of that
shutdown is not safe if you are leaving the power on, and it definitely
gets in the way of using sysrq or pressing ctrl-alt-del.  Since the
shutdown happens in generic code there is no way to fix this in
architecture specific code :(

Some machines are kernel oopsing today because of this.

The simple solution is to turn LINUX_REBOOT_CMD_POWER_OFF into
LINUX_REBOOT_CMD_HALT if power_off functionality is not implemented.

This has the unfortunate side effect of disabling the power off
functionality on architectures that leave pm_power_off to null and still
implement something in machine_power_off.  And it will break the build on
some architectures that don't have a pm_power_off variable at all.

On both counts I say tough.

For architectures like alpha that don't implement the pm_power_off variable
pm_power_off is declared in linux/pm.h and it is a generic part of our
power management code, and all architectures should implement it.

For architectures like parisc that have a default power off method in
machine_power_off if pm_power_off is not implemented or fails.  It is easy
enough to set the pm_power_off variable.  And nothing bad happens there,
the machines just stop powering off.

The current semantics are impossible without a flag at the top level so we
can avoid the problem code if a power off is not implemented.  pm_power_off
is as good a flag as any with the bonus that it works without modification
on at least x86, x86_64, powerpc, and ppc today.

Andrew can you pick this up and put this in the mm tree.  Kernels that
don't compile or don't power off seem saner than kernels that oops or
panic.  Until we get the arch specific patches for the problem
architectures this probably isn't smart to push into the stable kernel.
Unfortunately I don't have the time at the moment to walk through every
architecture and make them work.  And even if I did I couldn't test it :(

From: Hirokazu Takata <takata@linux-m32r.org>

    Add pm_power_off() for build fix of arch/m32r/kernel/process.c.

From: Miklos Szeredi <miklos@szeredi.hu>

    UML build fix

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Hayato Fujiwara <fujiwara@linux-m32r.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:00 -08:00
Christoph Hellwig a885c8c431 [PATCH] Add block_device_operations.getgeo block device method
HDIO_GETGEO is implemented in most block drivers, and all of them have to
duplicate the code to copy the structure to userspace, as well as getting
the start sector.  This patch moves that to common code [1] and adds a
->getgeo method to fill out the raw kernel hd_geometry structure.  For many
drivers this means ->ioctl can go away now.

[1] the s390 block drivers are odd in this respect.  xpram sets ->start
    to 4 always which seems more than odd, and the dasd driver shifts
    the start offset around, probably because of it's non-standard
    sector size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@suse.de>
Cc: <mike.miller@hp.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:54 -08:00
Adrian Bunk eafbaa9469 [PATCH] uml: prevent MODE_SKAS=n and MODE_TT=n
If MODE_TT=n, MODE_SKAS must be y.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:40 -08:00
Jeff Dike c0a689d05d [PATCH] uml: whitespace cleanup
This fixes some mangled whitespace added by the earlier trap_user.c patch.

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>
2006-01-08 20:13:40 -08:00
Gennady Sharapov c66fdd5e32 [PATCH] uml: merge trap_user.c and trap_kern.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This joins trap_user.c and trap_kernel.c files.

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
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>
2006-01-08 20:13:39 -08:00
Gennady Sharapov ea2ba7dc3d [PATCH] uml: move libc-dependent code from trap_user.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from trap_user.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 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Gennady Sharapov 0805d89c15 [PATCH] uml: move libc-dependent code from signal_user.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from signal_user.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 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Jeff Dike 8d93c700a4 [PATCH] uml: free network IRQ correctly
Free the network IRQ when closing down the network devices at shutdown.
Delete the device from the opened devices list on close.

These prevent an -EBADF when later disabling SIGIO on all extant descriptors
and a complaint from free_irq about freeing the IRQ twice.

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>
2006-01-06 08:33:48 -08:00
Jeff Dike 3a331a511a [PATCH] uml: fix whitespace in mconsole driver
Fix up some bogus spacing in the mconsole driver.  Also delete the
emacs formatting comment at the end.

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>
2006-01-06 08:33:48 -08:00
Jeff Dike 4111b025dc [PATCH] uml: capture printk output for mconsole sysrq
Pass sysrq output back to the mconsole client using the mechanism
introduced for stack output.

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>
2006-01-06 08:33:48 -08:00
Jeff Dike 6f517d3fc8 [PATCH] uml: capture printk output for mconsole stack
The stack command now sends the printk output back to the mconsole client.
This is done by registering a special console for the mconsole driver.  This
receives all printk output.  Normally, it is ignored, but when a stack command
is issued, any printk output will be sent back to the client.

This will capture any printk output, whether it is stack output or not, since
we can't tell the difference.

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>
2006-01-06 08:33:48 -08:00
Jeff Dike 7b033e1fde [PATCH] uml: add mconsole_reply variant with length param
This is needed for the console output patch, since we have a possibly
non-NULL-terminated string there.  So, the new interface takes a string and a
length, and the old interface calls strlen on its string and calls the new
interface with the length.

There's also a bit of whitespace cleanup.

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>
2006-01-06 08:33:47 -08:00
Jeff Dike 44700a4469 [PATCH] uml: better diagnostics for broken configs
Produce a compile-time error if both MODE_SKAS and MODE_TT are disabled.

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>
2006-01-06 08:33:47 -08:00
Jeff Dike e464bf2bed [PATCH] uml: SIGWINCH handling cleanup
Code cleanup - unregister_winch and winch_cleanup had some duplicate code.
This is now abstracted out into free_winch.

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>
2006-01-06 08:33:47 -08:00
Jeff Dike 7eebe8a9c5 [PATCH] uml: umid cleanup
This patch cleans up the umid code:

- The only_if_set argument to get_umid is gone.

- get_umid returns an empty string rather than NULL if there is no umid.

- umid_is_random is gone since its users went away.

- Some printfs were turned into printks because the code runs late enough
  that printk is working.

- Error paths were cleaned up.

- Some functions now return an error and let the caller print the error
  message rather than printing it themselves.  This eliminates the practice of
  passing a pointer to printf or printk in, depending on where in the boot
  process we are.

- Major tidying of not_dead_yet - mostly error path cleanup, plus a comment
  explaining why it doesn't react to errors the way you might expect.

- Calls to os_* interfaces that were moved under os are changed back to
  their native libc forms.

- snprintf, strlcpy, and their bounds-checking friends are used more often,
  replacing by-hand bounds checking in some places.

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>
2006-01-06 08:33:47 -08:00
Jeff Dike 2264c475e4 [PATCH] uml: separate libc-dependent umid code
I reworked Gennady's umid OS abstraction patch because the code shouldn't
be moved entirely to os.  As it turns out, I moved most of it anyway.  This
patch is the minimal one needed to move the code and have it work.
It turns out that the concept of the umid is OS-independent, but
almost everything else about the implementation is OS-dependent.

This is code movement without cleanup - a follow-on patch tidies
everything up without shuffling code around.

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>
2006-01-06 08:33:47 -08:00
Jeff Dike e4dcee8099 [PATCH] uml: Add throttling to console driver
This patch adds support for throttling and unthrottling input when the tty
driver can't handle it.

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>
2006-01-06 08:33:46 -08:00
Jeff Dike 9159c9dfff [PATCH] uml: Fix flip_buf full handling
When the tty flip_buf is full, it's a good idea to delay the input processing
for a jiffy, rather than just scheduling the tasklet immediately.

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>
2006-01-06 08:33:46 -08:00
Jeff Dike 165dc59116 [PATCH] uml: Simplify console opening/closing and irq registration
This patch simplifies the opening and closing of host console devices and the
registration and deregistration of IRQs.  The intent is to make it obvious
that an IRQ can't exist without an open file descriptor.

chan_enable will now open the channel, and when both opening and IRQ
registration are desired, this should be used.  Opening only is done for the
initial console, so that interface still needs to exist.

The free_irqs_later interface is now gone.  It was intended to avoid freeing
an IRQ while it was being processed.  It did this, but it didn't eliminate the
possiblity of free_irq being called from an interrupt, which is bad.  In its
place is a list of irqs to be freed, which is processed by the signal handler
just before exiting.  close_one_chan now disables irqs.

When a host device disappears, it is just closed, and that disables IRQs.

The device id registered with the IRQ is now the chan structure, not the tty.
This is because the interrupt arrives on a descriptor associated with the
channel.  This caused equivalent changes in the arguments to line_timer_cb.
line_disable is gone since it is not used any more.

The count field in the line structure is gone.  tty->count is used instead.

The complicated logic in sigio_handler with freeing IRQs when necessary and
making sure its idea of the next irq is correct is now much simpler.  The irq
list can't be rearranged underneath it, so it is now a simple list walk.

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>
2006-01-06 08:33:46 -08:00
Jeff Dike 1f80171e81 [PATCH] uml: move console configuration
This patch changes when console devices are configured in order to prepare the
ground for the next patch.

parse_chan_pair is now done earlier, when initcalls are run, rather than when
the device is opened.

When a host device disappears, the channel list is closed, but not freed.
This is required by the previous change.  line_config now takes the options
structure as an argument, and line_open doesn't.

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>
2006-01-06 08:33:46 -08:00
Jeff Dike 418e55d49b [PATCH] uml: line_setup interface change
line_setup is changed to return the device which it set up, rather than just
success or failure.  This will be important in the line-config patch.

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>
2006-01-06 08:33:46 -08:00
Jeff Dike 9010772cdf [PATCH] uml: Add static initializations and declarations
Some structure fields were being dynamically initialized when they could be
initialized at compile-time instead.  This also makes some declarations static
(in the C sense).

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>
2006-01-06 08:33:46 -08:00
Jeff Dike d571cd18f2 [PATCH] uml: Move mconsole support out of generic code
A bit of restructuring which eliminates the all_allowed argument (which is
mconsole-specific) to line_setup.  That logic is moved to the mconsole
callback.

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>
2006-01-06 08:33:45 -08:00
Jeff Dike 88890b8874 [PATCH] uml: Remove unneeded structure field
This removes a structure field which turned out to be pointless, and
references to it.

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>
2006-01-06 08:33:45 -08:00
Jeff Dike 0834cc77af [PATCH] uml: use ARRAY_SIZE
This patch replaces instances of "sizeof(foo)/sizeof(foo[0])" with
ARRAY_SIZE(foo), which expands to the same thing.

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>
2006-01-06 08:33:45 -08:00
Jeff Dike d50084a299 [PATCH] uml: Formatting changes
This patch makes a bunch of non-functional changes -
    return(foo); becomes return foo;
    some statements are broken across lines for readability
    some trailing whitespace is cleaned up
    open_one_chan took four arguments, three of which could be
       deduced from the first.  Accordingly, they were eliminated.
    some examples of "} else {" had a newline added
    some whitespace cleanup in the indentation
    lines_init got some control flow cleanup
    some long lines were broken
    removed another emacs-specific C formatting comment

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>
2006-01-06 08:33:45 -08:00
Jeff Dike 1b57e9c278 [PATCH] uml: non-void functions should return something
There are a few functions which are declared to return something, but don't.
These are actually infinite loops which are forced to be declared as non-void.
 This makes them all return 0.

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>
2006-01-06 08:33:45 -08:00
Jeff Dike 970d6e3a34 [PATCH] uml: use kstrdup
There were a bunch of calls to uml_strdup dating from before kstrdup was
introduced.  This changes those calls.  It doesn't eliminate the definition
since there is still a couple of calls in userspace code (which should
probably call the libc strdup).

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>
2006-01-06 08:33:45 -08:00
Paolo 'Blaisorblade' Giarrusso 63b4444241 [PATCH] uml: fix compilation with CONFIG_MODE_TT disabled
Fix UML compilation when SKAS mode is disabled. Indeed, we were compiling
SKAS-only object files, which failed due to some SKAS-only headers being
excluded from the search path.

Thanks to the bug report from Pekka J Enberg.

Acked-by: Pekka J Enberg <penberg (at) cs ! helsinki ! fi>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-29 09:48:15 -08:00
Paolo 'Blaisorblade' Giarrusso 74433c0fe1 [PATCH] Hostfs: update for new glibc - add missing symbol exports
Today, when compiling UML, I got warnings for two used unexported symbols:
readdir64 and truncate64. Indeed, my glibc headers are aliasing readdir to
readdir64 and truncate to truncate64 (and so on).

I'm then adding additional exports. Since I've no idea if the symbols where
always provided in the supported glibc's, I've added weak definitions too.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-29 09:48:15 -08:00
Paolo 'Blaisorblade' Giarrusso 516949480d [PATCH] uml: fix random segfaults at bootup
Don't use printk() where "current_thread_info()" is crap.

Until when we switch to running on init_stack, current_thread_info() evaluates
to crap. Printk uses "current" at times (in detail, &current is evaluated with
CONFIG_DEBUG_SPINLOCK to check the spinlock owner task).

And this leads to random segmentation faults.

Exactly, what happens is that &current = *(current_thread_info()), i.e. round
down $esp and dereference the value. I.e. access the stack below $esp, which
causes SIGSEGV on a VM_GROWSDOWN vma (see arch/i386/mm/fault.c).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-29 09:48:15 -08:00
Jeff Dike 5b7b15afee [PATCH] uml skas0: stop gcc's insanity
With Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>

UML skas0 stub has been miscompiling for many people (incidentally not
the authors), depending on the used GCC versions.

I think (and testing on some GCC versions shows) this patch avoids the
fundamental issue which is behind this, namely gcc using the stack when
we have just replaced it, behind gcc's back.  The remapping and storage
of the return value is hidden in a blob of asm, hopefully giving gcc no
room for creativity.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-18 11:19:44 -08:00
Paolo 'Blaisorblade' Giarrusso 76c842d8f8 [PATCH] uml - fix some funkiness in Kconfig
So you may have seen the miniconfig stuff wander by, which means that my
build script exits if there's a .config error, and we have this:

  fs/Kconfig:1749:warning: 'select' used by config symbol 'CIFS_UPCALL'
	refer to undefined symbol 'CONNECTOR'

This makes it shut up.

Signed-off-by: Rob Landley <rob@landley.net>
[ Verified it makes sense. ]
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-18 11:19:44 -08:00
Rob Landley 53c0b59dcd [PATCH] uml: fix dynamic linking on some 64-bit distros
With Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>

The current UML build assumes that on x86-64 systems, /lib is a symlink
to /lib64, but in some distributions (like PLD and CentOS) they are
separate directories, so the 64 bit library loader isn't found.  This
patch inserts /lib64 at the start of the rpath on x86-64 UML builds.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-18 11:19:44 -08:00
Paolo 'Blaisorblade' Giarrusso 9ce7677cfd [PATCH] uml: arch/um/scripts/Makefile.rules - remove duplicated code
Duplicated code - the patch adding it was probably applied twice without
enough care.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-18 11:19:44 -08:00
Pekka J Enberg bf001b2679 [PATCH] uml: fix compile error for tt
arch/um/kernel/tt/uaccess.c: In function `copy_from_user_tt':
arch/um/kernel/tt/uaccess.c:11: error: `FIXADDR_USER_START' undeclared (first use in this function)
arch/um/kernel/tt/uaccess.c:11: error: (Each undeclared identifier is reported only once
arch/um/kernel/tt/uaccess.c:11: error: for each function it appears in.)

I get the compile error when I disable CONFIG_MODE_SKAS.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Paolo 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>
2005-12-12 08:57:43 -08:00
Jeff Dike aa1a64ee12 [PATCH] uml: eliminate use of libc PAGE_SIZE
On some systems, libc PAGE_SIZE calls getpagesize, which can't happen from a
stub.  So, I use UM_KERN_PAGE_SIZE, which is less variable in its definition,
instead.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:41 -08:00
Jeff Dike 17d469715c [PATCH] uml: properly invoke x86_64 system calls
This patch makes stub_segv use the stub_syscall macros.  This was needed
anyway, but the bug that prompted this was the discovery that gcc was storing
stuff in RCX, which is trashed across a system call.  This is exactly the sort
of problem that the new macros fix.

There is a stub_syscall0 for getpid.  stub_segv was changed to be a libc file,
and that caused some include changes.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:41 -08:00
Jeff Dike e23181deec [PATCH] uml: eliminate anonymous union and clean up symlink lossage
This gives a name to the anonymous union introduced in skas-hold-own-ldt,
allowing to build on a wider range of gccs.

It also removes ldt.h, which somehow became real, and replaces it with a
symlink, and creates ldt-x86_64.h as a copy of ldt-i386.h for now.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:41 -08:00
Jeff Dike 39d730ab87 [PATCH] uml: eliminate use of local in clone stub
We have a bug in the i386 stub_syscall6 which pushes ebp before the system
call and pops it afterwards.  Because we use syscall6 to remap the stack, the
old contents of the stack (and the former value of ebp) are no longer
available.  Some versions of gcc make from a real local, accessed through ebp,
despite my efforts to make it obvious that references to from are really
constants.  This patch attempts to make it even more obvious by eliminating
from and using a macro to access the stub's data explicitly with constants.

My original thinking on this was to replace syscall6 with a remap_stack
interface which saved ebp someplace and restored it afterwards.  The problem
is that there are no registers to put it in, except for esp.  That could work,
since we can store a constant in esp after the mmap because we just replaced
the stack.  However, this approach seems a tad cleaner.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:41 -08:00
Paolo 'Blaisorblade' Giarrusso ba260e23ef [PATCH] uml: fix daemon transport exit path bug
Fix some exit path bugs in the daemon driver.

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 18:14:15 -08:00
Paolo 'Blaisorblade' Giarrusso 7a590611c0 [PATCH] uml: fix access_ok
The access_ok_tt() macro is bogus, in that a read access is unconditionally
considered valid.

I couldn't find in SCM logs the introduction of this check, but I went back to
2.4.20-1um and the definition was the same.

Possibly this was done to avoid problems with missing set_fs() calls, but
there can't be any I think because they would fail with SKAS mode.
TT-specific code is still to check.

Also, this patch joins common code together, and makes the "address range
wrapping" check happen for all cases, rather than for only some.

This may, possibly, be reoptimized at some time, but the current code doesn't
seem clever, just confused.

* Important: I've also had to change references to access_ok_{tt,skas} back to
  access_ok - the kernel wasn't that happy otherwise.

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 18:14:15 -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
Paolo 'Blaisorblade' Giarrusso fd9bc53b99 [PATCH] uml console channels: remove console_write wrappers
We were using a long series of (stupid) wrappers which all call
generic_console_write().  Since the wrappers only change the 4th param, which
is unused by the called proc, remove them and call generic_console_write()
directly.

If needed at any time in the future to reintroduce this stuff, the member
could be moved to a generic struct, to avoid this duplicated handling.

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
Paolo 'Blaisorblade' Giarrusso c50d2c4d66 [PATCH] uml: fix mcast network driver error handling
printk clears the host errno (I verified this in debugging and it's reasonable
enough, given that it ends via a write call on some fd, especially since
printk() goes on /dev/tty0 which is often the host stdout).  So save errno
earlier.  There's no reason to change the printk calls to use -err rather than
errno - the assignment can't clear errno.

And in the first failure path, we used to return 0 too (and this time more
clearly), which is totally wrong.  0 is a success fd, which is then registered
and gives a "registering fd twice" warning.

Finally, fix up some whitespace.

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
Paolo 'Blaisorblade' Giarrusso 85977376c7 [PATCH] uml: fixups for "reuse i386 cpu-specific tuning"
A few fixups - show the new submenu only for x86 subarchitecture (it does not
make sense to show it for x86_64 users) and remove X86_CMPXCHG, which is now a
duplicate of Kconfig.i386, even though Kconfig doesn't complain (we also miss
the dependency on !M386 CPU).

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
Paolo 'Blaisorblade' Giarrusso 3b8d108a6e [PATCH] uml: micro fixups to arch Kconfig
Remove a stone-age comment (UM *does* have a MMU, i.e.  the host), and fix a
dependency (introduced in commit 02edeb586a) to
do what was intended.

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