Convert all remaining os_{read_write}_file users to use the simple
{read,write} wrappers, os_{read_write}_file_k.
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>
Sanitise gfp flags; it actually is an atomic context, so drop the
GFP_KERNEL part.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of writing entire structures between UML and the I/O thread, we send
pointers. This cuts down on the amount of data being copied and possibly
allows more requests to be pending between the two.
This requires that the requests be kmalloced and freed instead of living on
the stack.
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>
Send as many I/O requests to the I/O thread as possible, even though it will
still only handle one at a time. This provides an opportunity to reduce
latency by starting one request before the previous one has been finished in
the driver.
Request handling is somewhat modernized by requesting sg pieces of a request
and handling them separately, finishing off the entire request after all the
pieces are done.
When a request queue stalls, normally because its pipe to the I/O thread is
full, it is put on the restart list. This list is processed by starting up
the queues on it whenever there is some indication that progress might be
possible again. Currently, this happens in the driver interrupt routine.
Some requests have been finished, so there is likely to be room in the pipe
again.
This almost doubles throughput when copying data between devices, but made no
noticable difference on anything else I tried.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus 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: 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>
Define release methods for the ubd and net drivers. They contain as much of
the remove methods as make sense. All error checking must have already been
done as well as anything else that might be holding a reference on the device
kobject.
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>
userspace code used to have to call the kernelspace function page_size() in
order to determine the value of the kernel's PAGE_SIZE. Since this is now
available directly from kern_constants.h as UM_KERN_PAGE_SIZE, page_size() can
be deleted and calls changed to use the constant.
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>
Calls lines_init() *after* xterm_title is modified to include umid.
Signed-off-by: Davide Brini <davide.brini@unibo.it>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Acked-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To look at users I did:
$ find arch/um/ include/asm-um -name '*.[ch]'|xargs grep -r 'net_kern\.h'
+-l|xargs grep '\<user\>'
Most users just cast user to the appropriate pointer, the remaining ones are
fixed here. In net_kern.c, I'm almost sure that save trick is not needed
anymore, but I've not verified it.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
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>
Avoid using the temporary buffer introduced by previous patch to hold the
device name.
Btw, avoid leaking device on an error path. Other error paths may need
cleanup.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
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>
Improve checking and diagnostics for broadcast and multicast Ethernet MAC
addresses, and distinguish between those cases in output; also make sure the
device is assigned a MAC address valid only locally to avoid collisions.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
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>
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>
Rescue the useful contents of the soon-to-be-gone user-util.h.
pty.c now gets ptsname from stdlib.h like it should have always done.
CATCH_EINTR is now in os.h, although perhaps all usage should be under
os-Linux at some point.
get_pty is also in os.h.
This patch restores the old definition of ARRAY_SIZE in user.h. This file is
included only in userspace files, so there will be no conflict with the
kernel's new ARRAY_SIZE. The copy of the kernel's ARRAY_SIZE and associated
infrastructure is now gone.
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>
This fixes a number of problems associated with network interface hotplug.
The userspace initialization function can fail in some cases, but the
failure was never passed back to eth_configure, which proceeded with the
configuration. This results in a zombie device that is present, but can't
work. This is fixed by allowing the initialization routines to return an
error, which is checked, and the configuration aborted on failure.
eth_configure failed to check for many failures. Even when it did check,
it didn't undo whatever initializations has already happened, so a present,
but partially initialized and non-working device could result. It now
checks everything that can fail, and bails out, undoing whatever had been
done.
The return value of eth_configure was always ignored, so it is now just
void.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
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>
If a disk fails to open, i.e. its host file doesn't exist, it won't be
removable because the hot-unplug code checks the existence of its gendisk.
This won't exist because it is only allocated for successfully opened disks.
Thus, a typo on the command line can result in a unusable and unfixable disk.
This is fixed by freeing the gendisk if it's there, but not letting that
affect the removal.
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>
For the places where we need a pointer to the mac header, it is still legal to
touch skb->mac.raw directly if just adding to, subtracting from or setting it
to another layer header.
This one also converts some more cases to skb_reset_mac_header() that my
regex missed as it had no spaces before nor after '=', ugh.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can
later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.
This one touches just the most simple case, next will handle the slightly more
"complex" cases.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As the comment immediately preceding this points out, this list is changed in
irq context, so it needs to be protected with spin_lock_irqsave in process
context when it is processed.
Sometimes, gcc should just compile the comments and forget the code.
The IRQ side of this was better, in the sense that it blocked and unblocked
interrupts, but it still should have saved and restored them.
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>
Fix a NULL dereference when unplugging a device. The default value of
err_msg wants to be "" in case the driver doesn't modify 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>
Commit 62f96cb01e introduced per-devices
queues and locks, which was fine as far as it went, but left in place a
global which controlled access to submitting requests to the host. This
should have been made per-device as well, since it causes I/O hangs when
multiple block devices are in use.
This patch fixes that by replacing the global with an activity flag in the
device structure in order to tell whether the queue is currently being run.
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>
Avoid reusing userspace errno twice - it can be cleared by libc code
everywhere (in particular printk() does clear it in my setup).
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix confusion about call context - comments and code are inconsistent and
plain wrong, my fault.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since both UML consoles do not use percpu variables, they may be called when
the cpu is still offline, and they may be marked CON_ANYTIME (this is
documented in kernel/printk.c, grep for CON_ANYTIME to find mentions of this).
Works well in testing done with lock debug enabled, should be safe but is not
needed for next release.
This would probably help also stderr_console.c, but this is yet to test.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Memory allocated by mcast_user_init must be freed in the matching mcast_remove.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
[akpm@osdl.org: sparc64 fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Of kernel subsystems that work with pids the tty layer is probably the largest
consumer. But it has the nice virtue that the assiation with a session only
lasts until the session leader exits. Which means that no reference counting
is required. So using struct pid winds up being a simple optimization to
avoid hash table lookups.
In the long term the use of pid_nr also ensures that when we have multiple pid
spaces mixed everything will work correctly.
Signed-off-by: Eric W. Biederman <eric@maxwell.lnxi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug: pnx8550 code creates directory but resets ->nlink to 1.
create_proc_entry() et al will correctly set ->nlink for you.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an error message when two umids are put on the command line.
umid.h is kind of pointless since it only declares one thing, and that
is already declared in os.h.
Commented the lack of locking of some data in os-Linux/umid.h.
Signed-off-by: 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>
Some small locking and formatting fixes in the ubd driver.
Signed-off-by: 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>
Replace global queue and lock with per-device queues and locks. Mostly a
straightforward replacement of ubd_io_lock with dev->lock and ubd_queue with
dev->queue.
Complications -
There was no way to get a request struct (and queue) from the
structure sent to the io_thread, so a pointer to the request was
added. This is needed in ubd_handler in order to kick do_ubd_request
to process another request.
Queue initialization is moved from ubd_init to ubd_add.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to initialize lists properly.
Signed-off-by: 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>
Eliminate the open_mutex after complaints from Blaisorblade. It turns out
that the tty count provides the information needed to tell whether we are the
first opener or last closer.
Signed-off-by: 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>
Remove the last vestiges of devfs from console registration. Change the name
of the function, plus remove a couple of unused fields from the line_driver
structure.
struct lines is no longer needed, all traces of it are gone.
The only way that I can see to mark a structure as being almost-const is to
individually const the fields. This is the case for the line_driver
structure, which has only one modifiable field - a list_head in a
sub-structure.
Signed-off-by: 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>
The chan_opts structure is mostly const, and needs no locking. Comment the
lack of locking on the one field that can change.
Make all the other fields const. It turned out that console_open_chan didn't
use its chan_opts argument, so that is deleted from the function and its
callers.
Signed-off-by: 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>
Comment the lack of locking.
Signed-off-by: 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>
A couple of list_head declarations can be improved through the use of
LIST_HEAD().
Signed-off-by: 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>
Add some missing locking to walks of the transports and opened lists.
Delete some dead code.
Comment the lack of some locking.
Signed-off-by: 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>
Whitespace and style fixes.
Signed-off-by: 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>
Make a couple of variables static.
Signed-off-by: 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>
Locking fixes. Locking was totally lacking for the mconsole_devices, which
got a spin lock, and the unplugged pages data, which got a mutex.
The locking of the mconsole console output code was confused. Now, the
console_lock (renamed to client_lock) protects the clients list.
Signed-off-by: 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>
Whitespace and style fixes.
Signed-off-by: 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>
Comment the lack of locking and make a couple of variables static.
Signed-off-by: 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>
Whitespace and style fixes.
Signed-off-by: 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>
Replace BKL use with a spinlock.
Also fix the control so that open doesn't return holding a lock.
Signed-off-by: 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>
Some whitespace and coding style cleanups in the network driver code.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The registration of host network transports needed some locking. The
transport list itself is locked, but calls to the registration routines are
not. This is compensated for by checking that a transport structure is not
yet on any list.
I also took the opportunity to const all fields in the transport structure
except the list, which obviously can be modified.
Signed-off-by: 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>
Fix (i.e. add some) the locking around the irqs_to_free list.
Signed-off-by: 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>
Some comment and whitespace cleanups in the console and mconsole code.
Signed-off-by: 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>
I noticed that errors happening while hotplugging devices from the host were
never returned back to the mconsole client. In some cases, success was
returned instead of even an information-free error.
This patch cleans that up by having the low-level configuration code pass back
an error string along with an error code. At the top level, which knows
whether it is early boot time or responding to an mconsole request, the string
is printk'd or returned to the mconsole client.
There are also whitespace and trivial code cleanups in the surrounding code.
Signed-off-by: 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>
Clean up the console driver locking. There are various problems here,
including sleeping under a spinlock and spinlock recursion, some of which are
fixed here. This patch deals with the locking involved with opens and closes.
The problem is that an mconsole request to change a console's configuration
can race with an open. Changing a configuration should only be done when a
console isn't opened. Also, an open must be looking at a stable
configuration. In addition, a get configuration request must observe the same
locking since it must also see a stable configuration. With the old locking,
it was possible for this to hang indefinitely in some cases because open would
block for a long time waiting for a connection from the host while holding the
lock needed by the mconsole request.
As explained in the long comment, this is fixed by adding a spinlock for the
use count and configuration and a mutex for the actual open and close.
Signed-off-by: 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>
Fix up the work on stack and exit scope trouble by placing the work_struct
in the uml_net_private data.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is the grungy swap all the occurrences in the right places patch that
goes with the updates. At this point we have the same functionality as
before (except that sgttyb() returns speeds not zero) and are ready to
begin turning new stuff on providing nobody reports lots of bugs
If you are a tty driver author converting an out of tree driver the only
impact should be termios->ktermios name changes for the speed/property
setting functions from your upper layers.
If you are implementing your own TCGETS function before then your driver
was broken already and its about to get a whole lot more painful for you so
please fix it 8)
Also fill in c_ispeed/ospeed on init for most devices, although the current
code will do this for you anyway but I'd like eventually to lose that extra
paranoia
[akpm@osdl.org: bluetooth fix]
[mp3@de.ibm.com: sclp fix]
[mp3@de.ibm.com: warning fix for tty3270]
[hugh@veritas.com: fix tty_ioctl powerpc build]
[jdike@addtoit.com: uml: fix ->set_termios declaration]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.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>
When the UML network driver generates random MACs for its devices, it was
possible for a number of UMLs to get the same MACs because the ethernet
initialization was done before the random pool was properly seeded.
This patch moves the initialization later so that it gets better randomness.
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>
arch/um/drivers/chan_kern.c:643: error: conflicting types for 'chan_interrupt'
arch/um/include/chan_kern.h:31: error: previous declaration of 'chan_interrupt'
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix up arch-specific work items where possible to use the new work_struct and
delayed_work structs.
Three places that enqueue bits of their stack and then return have been marked
with #error as this is not permitted.
Signed-Off-By: David Howells <dhowells@redhat.com>
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>
Fix a small memory leak in ubd_config, and clearify the confusion which lead
to it.
Then, some little changes not affecting operations -
* move init functions together,
* add a comment about a potential problem in case of some evolution in the block layer,
* mark all initcalls as static __init functions
* mark an used once little function as inline
* document that mconsole methods are all called in process context (was
triggered when checking ubd mconsole methods).
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>
To simplify error handling, make sure fd is saved into ubd_dev->fd only when
we are sure it is an fd and not an error code.
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>
Use bitfields for boolean fields in ubd data structure.
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>
Pure whitespace and style fixes split out from subsequent patch. Some changes
(err -> ret) don't make sense now, only later, but I split them out anyway
since they cluttered the patch.
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>
do_ubd is actually just a boolean variable - the way it is used currently is a
leftover from the old 2.4 block layer, but it is still used; its use is
suspicious, but removing it would be too intrusive for now and needs more
thinking.
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>
Add some comments about requirements for ubd_io_lock and expand its use.
When an irq signals that the "controller" (i.e. another thread on the host,
which does the actual requests and is the only one blocked on I/O on the host)
has done some work, we call again the request function ourselves
(do_ubd_request).
We now do that with ubd_io_lock held - that's useful to protect against
concurrent calls to elv_next_request and so on.
XXX: Maybe we shouldn't call at all the request function. Input needed on
this. Are we supposed to plug and unplug the queue? That code "indirectly"
does that by setting a flag, called do_ubd, which makes the request function
return (it's a residual of 2.4 block layer interface).
Meanwhile, however, merge this patch, which improves things.
Cc: Jens Axboe <axboe@suse.de>
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>
This lock protects ubd setup and teardown, so is only used in process context;
beyond that, during such setup memory allocations must be performed and some
generic functions which can sleep must be called (such as add_disk()). So the
only correct solution is to make it a mutex instead of a spin_lock. No other
change is done - this lock must be acquired in different places but it's done
afterwards.
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>
To rethink locking, I needed to understand well what each function does.
While doing this I renamed some:
* ubd_close -> ubd_close_dev (since it pairs with ubd_open_dev)
* ubd_new_disk -> ubd_disk_register (it handles registration with the block
layer - one hopes this makes clearer the difference with ubd_add())
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>
Rename the ubd_dev array to ubd_devs and then call any "struct ubd" ubd_dev
instead of dev, which doesn't make clear what we're treating (and no, it's not
hungarian notation - not any more than calling all vm_area_struct vma or all
inodes inode).
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>
Add documentation about some fields in struct ubd, whose meaning is
non-obvious due to struct names (should change names altogether, I agree).
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>
With 256 minors and 16 minors used per each UBD device, we can allow the use
of up to 16 UBD devices per UML.
Also chnage parse_unit and leave to the caller (which already do it) the check
for excess numbers, since this is just supposed to do raw parsing.
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>
* when we have stop/sysrq/go, we get pt_regs of whatever executes
mc_work_proc(). Would be better to see what we had at the time of
interrupt that got us stop.
* stop/stop/stop..... will give stack overflow. Shouldn't allow stop
from mconsole_stop().
* stop/stop/go leaves us inside mconsole_stop() with
os_set_fd_block(req->originating_fd, 0);
reactivate_fd(req->originating_fd, MCONSOLE_IRQ);
just done by nested mconsole_stop(). Ditto.
* once we'd seen stop, there's a period when INTR commands are executed
out of order (as they should; we might have the things stuck badly
enough to never reach mconsole_stop(), but still not badly enough to
block mconsole_interrupt(); in that situation we _want_ things like
"cad" to be executed immediately). Once we enter monsole_stop(), all
INTR commands will be executed in order, mixed with PROC ones. We'd
better let user see that such change of behaviour has happened.
(Suggested by lennert).
* stack footprint of monsole_interrupt() is an atrocity; AFAICS we can
safely make struct mc_request req; static in function there.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When enabling the mmapper driver I got warnings because this "const"
miscdevice structure is passed to function as non-const pointer; unlike struct
tty_operations, however, I verified that misc_{de,}register _do_ modify their
parameter, so this const attribute must be removed.
Since the purpose of the change was to guarantee that no lock was needed, add
a comment to prove this differently.
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>
Freeing the stack is left uselessly to the caller of run_helper in some cases
- this is taken from run_helper_thread, but here it is useless, so no caller
needs it and the only place where this happens has a potential leak - in case
of error neither run_helper() nor xterm_open() call free_stack(). At this
point passing a pointer is not needed - the stack pointer should be passed
directly, but this change is not done here.
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>
user.h is too generic a header name. I've split out allocation routines from
it.
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>
Real fix for UML pt_regs stuff. Note set_irq_regs() logics in there...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The patch below corrects multiple occurances of "the the"
typos across several files, both in source comments and KConfig files.
There is no actual code changed, only text. Note this only affects the /arch
directory, and I believe I could find many more elsewhere. :)
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Replace references to system_utsname to the per-process uts namespace
where appropriate. This includes things like uname.
Changes: Per Eric Biederman's comments, use the per-process uts namespace
for ELF_PLATFORM, sunrpc, and parts of net/ipv4/ipconfig.c
[jdike@addtoit.com: UML fix]
[clg@fr.ibm.com: cleanup]
[akpm@osdl.org: build fix]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Andrey Savochkin <saw@sw.ru>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking. One of these
structures was a struct tty_operations. In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.
This patch declares all struct tty_operations in the tree as const. In all
cases, they are static and used only as input to tty_set_operations. As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.
53 drivers are affected. I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months. serial_core.c was the busiest one that I looked at.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
After Christophs SCSI change, the only usage left is RQ_ACTIVE
and RQ_INACTIVE. The block layer sets RQ_INACTIVE right before freeing
the request, so any check for RQ_INACTIVE in a driver is a bug and
indicates use-after-free.
So kill/clean the remaining users, straight forward.
Signed-off-by: Jens Axboe <axboe@suse.de>
Use the existing random_ether_addr() instead of cooking up my own
version. Pointed out by Dave Hollis and Jason Lunz.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix some stack abuse in the sysrq t path.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Close two file descriptor leaks, one in the ubd driver and one to
/proc/mounts. The ubd driver bug also leaked some vmalloc space. The
/proc/mounts leak was a descriptor that was just never closed.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some locking documentation and a cleanup. uml_exitcode is copied into a local
before sprintf sees it, in case sprintf does anything non-atomic with it.
The rest are comments about why certain globals don't need any kind of
locking.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mechanical, hopefully non-functional changes stemming from
setup_etheraddr always succeeding now that it always assigns a MAC,
either from the command line or generated randomly:
the test of the return of setup_etheraddr is removed, and code
dependent on it succeeding is now unconditional
setup_etheraddr can now be made void
struct uml_net.have_mac is now always 1, so tests of it can be
similarly removed, and uses of it can be replaced with 1
struct uml_net.have_mac is no longer used, so it can be removed
struct uml_net_private.have_mac is copied from struct uml_net, so
it is always 1
tests of uml_net_private.have_mac can be removed
uml_net_private.have_mac can now be removed
the only call to dev_ip_addr was removed, so it can be deleted
It also turns out that setup_etheraddr is called only once, from the same
file, so it can be static and its declaration removed from net_kern.h.
Similarly, set_ether_mac is defined and called only from one file.
Finally, setup_etheraddr and set_ether_mac were moved to avoid needing forward
declarations.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Assign a random MAC to an ethernet interface if one was not provided on the
command line. This became pressing when distros started bringing interfaces
up before assigning IPs to them. The previous pattern of assigning an IP then
bringing it up allowed the MAC to be generated from the first IP assigned.
However, once the thing is up, it's probably a bad idea to change the MAC, so
the MAC stayed initialized to fe:fd:0:0:0:0.
Now, if there is no MAC from the command line, one is generated. We use the
microseconds from gettimeofday (20 bits), plus the low 12 bits of the pid to
seed the random number generator. random() is called twice, with 16 bits of
each result used. I didn't want to have to try to fill in 32 bits optimally
given an arbitrary RAND_MAX, so I just assume that it is greater than 65536
and use 16 bits of each random() return.
There is also a bit of reformatting and whitespace cleanup here.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ifa_local, ifa_address, ifa_mask, ifa_broadcast and ifa_anycast are
net-endian. Annotated them and variables that are inferred to be
net-endian.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix an instance of ptr=alloc(sizeof(ptr)). Grepping showed no more instances
of this pattern.
Also fixed the formatting in the area.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make lots of structures const in order to make it obvious that they need no
locking.
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>
This spinlock can be taken on interrupt too, so spin_lock_irq[save] must be
used.
However, Documentation/networking/netdevices.txt explains we are called with
rtnl_lock() held - so we don't need to care about other concurrent opens.
Verified also in LDD3 and by direct checking. Also verified that the network
layer (through a state machine) guarantees us that nobody will close the
interface while it's being used. Please correct me if I'm wrong.
Also, we must check we don't sleep with irqs disabled!!! But anyway, this is
not news - we already can't sleep while holding a spinlock. Who says this is
guaranted really by the present code?
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clean set_ether_mac usage. Maybe could also be removed, but surely it can't
be a global function taking a void* argument.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There were a bunch of missed ARRAY_SIZE opportunities.
Also, some formatting fixes in the affected areas of code.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Handling a host mconsole version request must be done in a process context
rather than interrupt context now that utsname information can be
process-specific rather than global.
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>
The dedevfsification of UML left an unused variable behind.
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>
Add some more uses of the CATCH_EINTR wrapper.
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>
Fix a bunch of formatting problems.
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>
Use the new IRQF_ constants and remove the SA_INTERRUPT define
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: 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>
-mm in combination with an FC5 init started dying with 'stderr=1' because init
didn't like the lack of /dev/console and exited. The problem was that the
stderr console, which is intended to dump printk output to the terminal before
the regular console is initialized, isn't a tty, and so can't make
/dev/console operational.
However, since it is registered first, the normal console, when it is
registered, doesn't become the preferred console, and isn't attached to
/dev/console. Thus, /dev/console is never operational.
This patch makes the stderr console unregister itself in an initcall, which is
late enough that the normal console is registered. When that happens, the
normal console will become the preferred console and will be able to run
/dev/console.
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>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6: (22 commits)
[PATCH] devfs: Remove it from the feature_removal.txt file
[PATCH] devfs: Last little devfs cleanups throughout the kernel tree.
[PATCH] devfs: Rename TTY_DRIVER_NO_DEVFS to TTY_DRIVER_DYNAMIC_DEV
[PATCH] devfs: Remove the tty_driver devfs_name field as it's no longer needed
[PATCH] devfs: Remove the line_driver devfs_name field as it's no longer needed
[PATCH] devfs: Remove the videodevice devfs_name field as it's no longer needed
[PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
[PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed
[PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
[PATCH] devfs: Remove devfs_remove() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_bdev() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_symlink() function from the kernel tree
[PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
[PATCH] devfs: Remove devfs_*_tape() functions from the kernel tree
[PATCH] devfs: Remove devfs support from the sound subsystem
[PATCH] devfs: Remove devfs support from the ide subsystem.
[PATCH] devfs: Remove devfs support from the serial subsystem
[PATCH] devfs: Remove devfs from the init code
[PATCH] devfs: Remove devfs from the partition code
...
- proper prototypes for the following functions:
- ctrl_alt_del() (in include/linux/reboot.h)
- getrusage() (in include/linux/resource.h)
- make the following needlessly global functions static:
- kernel_restart_prepare()
- kernel_kexec()
[akpm@osdl.org: compile fix]
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I sent a patch, it was applied as cda402b283,
then it was applied again as 181ae4005d by
mistake. But while the 1st time it modified (correctly) cow_header_v3, the
2nd it modified cow_header_v3_broken.
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>
This is the minimal fix to make 64-bit UML binaries create 32-bit
compatible COW files and read them.
I've indeed tested that current code doesn't do this - the code gets
SIGFPE for a division by a value read at the wrong place, where 0 is
found.
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>
Since on some 64-bit systems __u64 is rightfully defined to unsigned long and
GCC recognizes anyway unsigned long and unsigned long long as different, fix
some types back to being unsigned long long to avoid warnings and errors (for
prototype mismatch) on those systems.
Thanks to the report by Wesley Emeneker wesleyemeneker (at) google (dot) 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>
The call to local_save_flags seems bogus since it is followed by
local_irq_restore, and it's intended to lock the list from concurrent
mconsole_interrupt invocations.
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>
Fix an hang on a pipe when run_helper() fails when called by change_tramp()
(i.e. when calling uml_net) - reproduced the bug and verified this fixes it.
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>
Now that GCC warns about format errors, fix them. Nothing able to cause a
crash, however.
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>
Fix two harmless warnings in 64-bit compilation (the 2nd doesn't trigger for
now because of a missing __attribute((format)) for cow_printf, but next
patches fix that).
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>
- Correct the layout of all header versions - make all them well-specified
for any external event. As we don't have 1-byte or 2-byte wide fields, the
32-bit layout (historical one) has no extra padding, so we can safely add
__attribute__((packed)).
- Add detection and reading of the broken 64-bit COW format which has been
around for a while - to allow safe migration to the correct 32-bit format.
Safe detection is possible, thanks to some luck with the existing format,
and it works in practice.
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>
This is the minimal fix to make 64-bit UML binaries create 32-bit compatible
COW files and read them. I've indeed tested that current code doesn't do this
- the code gets SIGFPE for a division by a value read at the wrong place,
where 0 is found.
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>
Change memory hotplug to use GFP_NOWAIT instead of GFP_ATOMIC, so that it
will grab memory without sleeping, but doesn't try to use the emergency
pools.
A small list initialization suggested by Daniel Phillips - don't initialize
lists which are just about to be list_add-ed.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
type-safe min() in arch/um/drivers/mconsole_kern.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
misc sparse annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
A number of UML initcalls were improperly returning 1. Also removed any
nearby emacs formatting comments.
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>
Changes since first version
added check for MADV_REMOVE support on the host
fixed error return botch
shrunk sprintf array by one character
This adds hotplug memory support to UML. The mconsole syntax is
config mem=[+-]n[KMG]
In other words, add or subtract some number of kilobytes, megabytes, or
gigabytes.
Unplugged pages are allocated and then madvise(MADV_TRUNCATE), which is a
currently experimental madvise extension. These pages are tracked so they
can be plugged back in later if the admin decides to give them back. The
first page to be unplugged is used to keep track of about 4M of other
pages. A list_head is the first thing on this page. The rest is filled
with addresses of other unplugged pages. This first page is not madvised,
obviously.
When this page is filled, the next page is used in a similar way and linked
onto a list with the first page. Etc. This whole process reverses when
pages are plugged back in. When a tracking page no longer tracks any
unplugged pages, then it is next in line for plugging, which is done by
freeing pages back to the kernel.
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>
The kernel's implementation of notifier chains is unsafe. There is no
protection against entries being added to or removed from a chain while the
chain is in use. The issues were discussed in this thread:
http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2
We noticed that notifier chains in the kernel fall into two basic usage
classes:
"Blocking" chains are always called from a process context
and the callout routines are allowed to sleep;
"Atomic" chains can be called from an atomic context and
the callout routines are not allowed to sleep.
We decided to codify this distinction and make it part of the API. Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name). New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain. The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.
With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed. For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections. (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)
There are some limitations, which should not be too hard to live with. For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem. Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain. (This did happen in a couple of places and the code
had to be changed to avoid it.)
Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization. Instead we use RCU. The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.
Here is the list of chains that we adjusted and their classifications. None
of them use the raw API, so for the moment it is only a placeholder.
ATOMIC CHAINS
-------------
arch/i386/kernel/traps.c: i386die_chain
arch/ia64/kernel/traps.c: ia64die_chain
arch/powerpc/kernel/traps.c: powerpc_die_chain
arch/sparc64/kernel/traps.c: sparc64die_chain
arch/x86_64/kernel/traps.c: die_chain
drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list
kernel/panic.c: panic_notifier_list
kernel/profile.c: task_free_notifier
net/bluetooth/hci_core.c: hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain
net/ipv6/addrconf.c: inet6addr_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain
net/netlink/af_netlink.c: netlink_chain
BLOCKING CHAINS
---------------
arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain
arch/s390/kernel/process.c: idle_chain
arch/x86_64/kernel/process.c idle_notifier
drivers/base/memory.c: memory_chain
drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list
drivers/macintosh/adb.c: adb_client_list
drivers/macintosh/via-pmu.c sleep_notifier_list
drivers/macintosh/via-pmu68k.c sleep_notifier_list
drivers/macintosh/windfarm_core.c wf_client_list
drivers/usb/core/notify.c usb_notifier_list
drivers/video/fbmem.c fb_notifier_list
kernel/cpu.c cpu_chain
kernel/module.c module_notify_list
kernel/profile.c munmap_notifier
kernel/profile.c task_exit_notifier
kernel/sys.c reboot_notifier_list
net/core/dev.c netdev_chain
net/decnet/dn_dev.c: dnaddr_chain
net/ipv4/devinet.c: inetaddr_chain
It's possible that some of these classifications are wrong. If they are,
please let us know or submit a patch to fix them. Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)
The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.
[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds a 'c' option to the ubd switch which turns off host file locking so
that the device can be shared, as with a cluster. There's also some
whitespace cleanup while I was in this file.
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>
Improve (especially for coherence) some prototypes, and return code of
init_cow_file in error case - for a short write return -EINVAL, otherwise
return the error we got!
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>
Do precise error handling: print precise error messages, distinguishing short
reads and read errors. This functions fails frequently enough for me so I
bothered doing this fix.
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>
Improve some error messages in the COW driver, and say V3, not V2, when
talking about V3 format. Also resync with our userspace code utility a bit
more.
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>
The network driver added an interface to the "opened" list when it was
configured, not when it was brought up, and removed it when it was taken down.
A sequence of ifconfig up, ifconfig down, ... caused it to be removed
multiple times from the list without being added in between, resulting in a
crash. This patch moves the add to when the interface is brought 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>
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>
Fix some simple sparse warnings - a lot more staticness and a misplaced
__user.
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>
The C99 initialization, with GCC's bad handling, for 6K wide structs (which
_aren't_ on the stack), is causing GCC to use 12K for these silly procs with 3
vars. Workaround this.
Note that .name = { '\0' } translates to memset(->name, 0, '->name' size) - I verified
this with GCC's docs and a testprogram.
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>
Fix a couple of typos.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Correct a bit of whitespace problems while working here.
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>
When the user specifies both a COW file and its backing file, if the previous
backing file is not found, currently UML tries again to use it and fails.
This can be corrected by changing same_backing_files() return value in that
case, so that the caller will try to change the COW file to point to the new
location, as already done in other cases.
Additionally, given the change in the meaning of the func, change its name,
invert its return value, so all values are inverted except when
stat(from_cow,&buf2) fails. And add some comments and two minor bugfixes -
remove a fd leak (return err rather than goto out) and a repeated check.
Tested well.
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>
In this error path, when the interface has had a problem, we call dev_close(),
which is disallowed for two reasons:
*) takes again the UML internal spinlock, inside the ->stop method of this
device
*) can be called in process context only, while we're in interrupt context.
I've also thought that calling dev_close() may be a wrong policy to follow,
but it's not up to me to decide that.
However, we may end up with multiple dev_close() queued on the same device.
But the initial test for (dev->flags & IFF_UP) makes this harmless, though -
and dev_close() is supposed to care about races with itself. So there's no
harm in delaying the shutdown, IMHO.
Something to mark the interface as "going to shutdown" would be appreciated,
but dev_deactivate has the same problems as dev_close(), so we can't use it
either.
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>
Pre-clear transport-specific private structure before passing it down.
In fact, I just got a slab corruption and kernel panic on exit because kfree()
was called on a pointer which probably was never allocated, BUT hadn't been
set to NULL by the driver.
As the code is full of such errors, I've decided for now to go the safe way
(we're talking about drivers), and to do the simple thing. I'm also starting
to fix drivers, and already sent a patch for the daemon transport.
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>
Avoid uninitialized data in the daemon_data structure. I used this transport
before doing proper setup before-hand, and I got some very nice SLAB
corruption due to freeing crap pointers. So just make sure to clear
everything when appropriate.
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>
The serial UML OS-abstraction layer patch (um/kernel dir).
This moves all systemcalls from user_util.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>
The HDIO_GETGEO patch left an unused variable in the UML block driver. This
gets rid of it.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
CON_PRINTBUFFER was a bad idea for the mconsole console. It causes the boot
output to be printed twice.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
This allows us to eliminate the casts in the drivers, and eventually
remove the use of the device_driver function pointer methods for
platform device drivers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Use schedule_timeout_interruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
ifa->ifa_address and ifa->ifa_mask are defined as __u32, but used as if they
were char[4].
Network code uses htons() to convert it. So UML's method to access these
fields is wrong for bigendians (e.g. s390)
I replaced bytewise copying by memcpy(), maybe even that might be removed, if
ifa->ifa_address/mask may be used immediately.
Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert everyone who uses platform_bus_type to include
linux/platform_device.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
The patch to use host AIO support that I submitted early after 2.6.13 exposed
some problems in the block driver. I have fixes for these, but am not
comfortable putting them into 2.6.14 at this late date. So, this patch reverts
the use of host AIO.
I will resubmit the original patch, plus fixes to the driver after 2.6.14
in order to get a reasonable amount of testing before they're exposed to
the general public.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix whitespace - I split this off the previous patch for easier review.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
After restoring the existing code, make it work also when included in
kernelspace code (which isn't currently the case, but at least this will prevent
people from "fixing" it as just happened).
Whitespace is fixed in next patch - it cluttered the diff too much.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Commit 44456d37b5, between 2.6.13-rc3 and -rc4,
was a "nice cleanup" which broke something. Revert the offending part.
It broke because:
a) because this part doesn't fall under the description
b) the author didn't know what he was doing here
c) the author didn't try to compile the existing code and see that it worked
perfectly.
d) the author didn't ask us what was happening
e) you didn't either, and somebody there should have learned that UML is a bit
different.
In fact, UML is special in linking to host libc and using its includes.
In particular, since host includes always define both __BIG_ENDIAN and
__LITTLE_ENDIAN, ntohll() macros started thinking to be in a big-endian world;
and on-disk compatibility was broken.
Many thanks go to Nix for reporting the problem and correctly diagnosing an
endianness problem.
Btw, this patch restores the previous code, which worked; but the definitions
would be uncorrect if used in kernelspace files.
Next patch addresses that.
Cc: Nix <nix@esperi.org.uk>, Olaf Hering <olh@suse.de>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Revert commit 12ebcd73e4, i.e. [PATCH] uml: run
mconsole "sysrq" in process context on request from Jeff Dike.
a) sysrq may be run when the scheduler is non-functioning
b) the warning I wanted to fix actually came from the fault handler run in
atomic context. But I fixed that not to take the semaphore in a separate
patch.
c) the fault handler is run because of a fault, and that fault was
unaffected by this patch.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
User get *a lot* confused when consoles don't work but we don't report
anything. And, as reported in the comment, using printk to report "your
console doesn't work" isn't likely to go that far.
Fix the problem on the base of this: stack consumption by host printf(). Use
kernel sprintf() and os_write_file, using a wild guess that one page will be
enough for the message, to preallocate the buffer with kmalloc().
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>
setup_initial_poll is only called with sigio_lock() held, so use appropriate
allocation.
Also, parse_chan() can also be called when holding a spinlock (see line_open()
-> parse_chan_pair()).
I have sporadic problems (spinlock taken twice, with spinlock debugging on UP)
which could be caused by a sequence like "take spinlock, alloc and go to
sleep, take again the spinlock in the other thread".
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>
Things are breaking horribly with sysrq called in interrupt context. I want
to try to fix it, but probably this is simpler. To tell the truth, sysrq is
normally run in interrupt context, so there shouldn't be any problem.
There's also a warning from the fault handler because it's run in atomic
context (I have a patch for that, only I deferred it). This is why I'm doing
this.
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>
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: 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>
linux/inet.h isn't needed, and on my system, is empty.
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>
This removes a file which is no longer used.
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>
This patch implements a stack trace for a thread, not unlike sysrq-t does.
The advantage to this is that a break point can be placed on showreqs, so that
upon showing the stack, you jump immediately into the debugger. While sysrq-t
does the same thing, sysrq-t shows *all* threads stacks. It also doesn't work
right now. In the future, I thought it might be acceptable to make this show
all pids stacks, but perhaps leaving well enough alone and just using sysrq-t
would be okay. For now, upon receiving the stack command, UML switches
context to that thread, dumps its registers, and then switches context back to
the original thread. Since UML compacts all threads into one of 4 host
threads, this sort of mechanism could be expanded in the future to include
other debugging helpers that sysrq does not cover.
Note by jdike - The main benefit to this is that it brings an arbitrary thread
back into context, where it can be examined by gdb. The fact that it dumps it
stack is secondary. This provides the capability to examine a sleeping
thread, which has existed in tt mode, but not in skas mode until now.
Also, the other threads, that sysrq doesn't cover, can be gdb-ed directly
anyway.
Signed-off-by: Allan Graves<allan.graves@gmail.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>
This adds AIO support to the ubd driver.
The driver breaks a struct request into IO requests to the host, based on the
hardware segments in the request and on any COW blocks covered by the request.
The ubd IO thread is gone, since there is now an equivalent thread in the AIO
module.
There is provision for multiple outstanding requests now. Requests aren't
retired until all pieces of it have been completed. The AIO requests have a
shared count, which is decremented as IO operations come in until it reaches
0. This can be possibly moved to the request struct - haven't looked at this
yet.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This cleans up the error path in ubd_open, causing it now to call ubd_close
appropriately when something fails.
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>
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>
- copy_from_user() can fail; ->write() must check its return value.
- severe buffer overruns both in ->read() and ->write() - lseek to the
end (i.e. to mmapper_size) and
if (count + *ppos > mmapper_size)
count = count + *ppos - mmapper_size;
will do absolutely nothing. Then it will call
copy_to_user(buf,&v_buf[*ppos],count);
with obvious results (similar for ->write()).
Fixed by turning read to simple_read_from_buffer() and by doing
normal limiting of count in ->write().
- gratitious lock_kernel() in ->mmap() - it's useless there.
- lots of gratuitous includes.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
printk() calls should include appropriate KERN_* constant.
Signed-off-by: Christophe Lucas <clucas@rotomalug.org>
Signed-off-by: Domen Puncer <domen@coderock.org>
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>
Just a Kbuild subtlety, not listing a target file inside targets causes it
to be rebuilt each time, and as a consequence everything depending on it is
rebuilt.
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>
turn many #if $undefined_string into #ifdef $undefined_string to fix some
warnings after -Wno-def was added to global CFLAGS
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch replaces the deprecated MODULE_PARM function by the new
module_param function.
Signed-off-by: Dominik Hackl <dominik@hackl.dhs.org>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The pcap support was not working because of some linking problems (expressing
the construct in Kbuild was a bit difficult) and because there was no user
request. Now that this has come back, here's the support.
This has been tested and works on both 32 and 64-bit hosts, even when
"cross-"building 32-bit binaries.
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>
Replace a semaphore (winch_handler_sem) used in atomic code with a
spinlock, and reduces as needed the amount of protected code to the bare
minimum (for instance no kmalloc calls are needed).
This fixes the last problems with spinlocking (in UP mode with DEBUG
options); the semaphore, taken inside spinlocks, caused a "spin_lock was
already locked" warning, without this patch.
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>
Clean up the hot-unplugging code. There is now an id procedure which is
called to figure out what device we're talking to. The error messages from
that are now done from mconsole_remove instead of the driver. remove is now
called with the device number, after it has been checked, so doesn't need to
do sanity checking on it.
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>
Here's a small patch to remove a few unnessesary NULL pointer checks before
kfree() in arch/um/drivers/daemon_user.c
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
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>
This occurrence of free_irq_by_irq_and_dev() was missed when converting UML
to the use of hw_controller_type->release.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>