Add kerneldoc to kernel/capability.c
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I believe that there is a problem with the handling of POSIX locks, which
the attached patch should address.

The problem appears to be a race between fcntl(2) and close(2).  A
multithreaded application could close a file descriptor at the same time as
it is trying to acquire a lock using the same file descriptor.  I would
suggest that that multithreaded application is not providing the proper
synchronization for itself, but the OS should still behave correctly.

SUS3 (Single UNIX Specification Version 3, read: POSIX) indicates that when
a file descriptor is closed, that all POSIX locks on the file, owned by the
process which closed the file descriptor, should be released.

The trick here is when those locks are released.  The current code releases
all locks which exist when close is processing, but any locks in progress
are handled when the last reference to the open file is released.

There are three cases to consider.

One is the simple case, a multithreaded (mt) process has a file open and
races to close it and acquire a lock on it.  In this case, the close will
release one reference to the open file and when the fcntl is done, it will
release the other reference.  For this situation, no locks should exist on
the file when both the close and fcntl operations are done.  The current
system will handle this case because the last reference to the open file is
being released.

The second case is when the mt process has dup(2)'d the file descriptor.
The close will release one reference to the file and the fcntl, when done,
will release another, but there will still be at least one more reference
to the open file.  One could argue that the existence of a lock on the file
after the close has completed is okay, because it was acquired after the
close operation and there is still a way for the application to release the
lock on the file, using an existing file descriptor.

The third case is when the mt process has forked, after opening the file
and either before or after becoming an mt process.  In this case, each
process would hold a reference to the open file.  For each process, this
degenerates to first case above.  However, the lock continues to exist
until both processes have released their references to the open file.  This
lock could block other lock requests.

The changes to release the lock when the last reference to the open file
aren't quite right because they would allow the lock to exist as long as
there was a reference to the open file.  This is too long.

The new proposed solution is to add support in the fcntl code path to
detect a race with close and then to release the lock which was just
acquired when such as race is detected.  This causes locks to be released
in a timely fashion and for the system to conform to the POSIX semantic
specification.

This was tested by instrumenting a kernel to detect the handling locks and
then running a program which generates case #3 above.  A dangling lock
could be reliably generated.  When the changes to detect the close/fcntl
race were added, a dangling lock could no longer be generated.

Cc: Matthew Wilcox <willy@debian.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

vmcp_write uses GPF_DMA for the memory allocation of the response buffer, so
it can use the low level function __cpcmd directly, no need to call the
wrapper.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix wrong move direction of timer values for cpu accounting in case of a
machine check that indicates a broken cpu timer.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Limit reported memory size to 2GB if running in 31 bit mode.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Tape driver fixes:
 - Added deferred condition handling to tape driver core.
 - Added ability to handle busy conditions.
 - Code cleanup.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Free dasd slab cache on module unload.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The FBA discipline does not use retries for failed requests.  A request fails
after the first unsuccessful start attempt.  There are some rare conditions
(e.g.  CIO path recovery) in which the start of an i/o on a fba device can
fail.  A tiny amount of retries is therefore reasonable.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When processing resource accessibility events, continue searching for further
affected subchannels if a link address is provided in the event information.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix debug data in case of an interface-control or channel-control check: don't
log the not yet accumulated interrupt-response-block, but the one we just
received.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The kernel uses the SIGP external call order code to signal other CPUs.  When
running with dedicated CPUs external calls don't get delivered immediately but
within a fixed polling invervall.  This can lead to delays where the system
appears to do nothing.  Replace the SIGP external call order with the SIGP
emergency call order since this one gets delivered immediately.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The atomic64 primitives are supposed to have 64-bit parameters instead of int.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The find_next_{zero}_bit primitives on s390* should never return a bit number
bigger then the bit field size.  In the case of a bitfield that doesn't end on
a word boundary, an offset that makes the search start at the last word of the
bit field and the last word doesn't contain any zero/one bits the search is
continued with a call to find_first_bit with a negative size.  The search
normally ends pretty quickly because the words following the bit field contain
a mix of zeros and ones.  But the bit number that is returned in this case is
too big.

To fix this and additional if to check for this case is needed.  To make the
code easier to read I removed the assembler parts from the
find_next_{zero}_bit functions, the C-ified code is as good.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Split spin lock and r/w lock implementation into a single try which is done
inline and an out of line function that repeatedly tries to get the lock
before doing the cpu_relax().  Add a system control to set the number of
retries before a cpu is yielded.

The reason for the spin lock retry is that the diagnose 0x44 that is used to
give up the virtual cpu is quite expensive.  For spin locks that are held only
for a short period of time the costs of the diagnoses outweights the savings
for spin locks that are held for a longer timer.  The default retry count is
1000.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

These changes are untested (I no longer have the hardware).
Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NMiles Bader <miles@gnu.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

  * Added abstraction layer for subarchs.
  * Added v32 support.
  * Renamed driver.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Acked-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

New CRIS sub architecture named v32.

From: Dave Jones <davej@redhat.com>

	Fix swapped kmalloc args
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Patches to make CRIS work with 2.6.12.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Include file for synchronous serial port driver.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Patches to support SMP.

* Each CPU has its own current_pgd.
* flush_tlb_range is implemented as flush_tlb_mm.
* Atomic operations implemented with spinlocks.
* Semaphores implemented with spinlocks.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

System-level profiler.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Patches to make it possible to add PCI support.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Memory management patches.

* SMP support.
* Non-executable stack (on v32).
* 4-level page tables.
* Added simple Thread Local Storage support.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

* Start threads with IRQs enabled.
* Move symbol exports to arch specific file.
* Prepare for real command line in the future.
* Handle csum for partition that crosses flash boundary.
* Set utsname.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use the generic IRQ framework
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Added I/O and DMA allocators to be used by drivers.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Updates to device drivers.

* Use I/O and DMA allocators.
* Use wait_event_interruptible instead of interrutiple_sleep_on.
* Added spinlocks SMP.
* Changed restore_flags to local_irq_restore etc.
* Updated IDE driver include to fit 2.6.12.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Improvements to crash debug code.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Changes to console.

* Added LF->CRLF translation
* Make use of real console framework.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Changes to configuration and build system.

* Added v32 sub architecture.
* Use generic hard IRQ.
* Added SMP options.
* Added options to OOPS at NMI and reboot at OOM.
* Made it possible to set objtree.
* Added option to select Kernel GDB serial port.
* Corrected Kconfig usage.
* Added system profiler.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Changes necessary to make the sub-arch split complete.
Signed-off-by: NMikael Starvik <starvik@axis.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There's no help text for CONFIG_DEBUG_STACKOVERFLOW - add one.
Signed-off-by: NJesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

There's no help text for CONFIG_DEBUG_STACKOVERFLOW - add one.
Signed-off-by: NJesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch has removed obsolete GIU driver for vr41xx.  This patch already
has been applied to mips tree.
Signed-off-by: NYoichi Yuasa <yuasa@hh.iij4u.or.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>