linux.git/fs/aio.c, branch v2.6.28

[PATCH] f_count may wrap around

2008-07-27T00:53:40+00:00

make it atomic_long_t; while we are at it, get rid of useless checks in affs,
hfs and hpfs - ->open() always has it equal to 1, ->release() - to 0.

Signed-off-by: Al Viro

kill PF_BORROWED_MM in favour of PF_KTHREAD

2008-07-25T17:53:39+00:00

Kill PF_BORROWED_MM.  Change use_mm/unuse_mm to not play with ->flags, and
do s/PF_BORROWED_MM/PF_KTHREAD/ for a couple of other users.

No functional changes yet.  But this allows us to do further
fixes/cleanups.

oom_kill/ptrace/etc often check "p->mm != NULL" to filter out the
kthreads, this is wrong because of use_mm().  The problem with
PF_BORROWED_MM is that we need task_lock() to avoid races.  With this
patch we can check PF_KTHREAD directly, or use a simple lockless helper:

	/* The result must not be dereferenced !!! */
	struct mm_struct *__get_task_mm(struct task_struct *tsk)
	{
		if (tsk->flags & PF_KTHREAD)
			return NULL;
		return tsk->mm;
	}

Note also ecard_task().  It runs with ->mm != NULL, but it's the kernel
thread without PF_BORROWED_MM.

Signed-off-by: Oleg Nesterov 
Cc: Roland McGrath 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

uml: activate_mm: remove the dead PF_BORROWED_MM check

2008-06-06T18:36:22+00:00

use_mm() was changed to use switch_mm() instead of activate_mm(), since
then nobody calls (and nobody should call) activate_mm() with
PF_BORROWED_MM bit set.

As Jeff Dike pointed out, we can also remove the "old != new" check, it is
always true.

Signed-off-by: Oleg Nesterov 
Cc: Jeff Dike 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

debugobjects: add timer specific object debugging code

2008-04-30T15:29:53+00:00

Add calls to the generic object debugging infrastructure and provide fixup
functions which allow to keep the system alive when recoverable problems have
been detected by the object debugging core code.

Signed-off-by: Thomas Gleixner 
Acked-by: Ingo Molnar 
Cc: Greg KH 
Cc: Randy Dunlap 
Cc: Kay Sievers 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aio: fix misleading comments

2008-04-29T15:06:29+00:00

The FIXME comments are inaccurate.
The locking comment over lookup_ioctx() is wrong.

Signed-off-by: Jeff Moyer 
Signed-off-by: Zach Brown 
Signed-off-by: Shen Feng 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Remove duplicated unlikely() in IS_ERR()

2008-04-29T15:06:25+00:00

Some drivers have duplicated unlikely() macros.  IS_ERR() already has
unlikely() in itself.

This patch cleans up such pointless code.

Signed-off-by: Hirofumi Nakagawa 
Acked-by: David S. Miller 
Acked-by: Jeff Garzik 
Cc: Paul Clements 
Cc: Richard Purdie 
Cc: Alessandro Zummo 
Cc: David Brownell 
Cc: James Bottomley 
Cc: Michael Halcrow 
Cc: Anton Altaparmakov 
Cc: Al Viro 
Cc: Carsten Otte 
Cc: Patrick McHardy 
Cc: Paul Mundt 
Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Acked-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs/aio.c: make 3 functions static

2008-04-29T15:06:00+00:00

Make the following needlessly global functions static:

- __put_ioctx()
- lookup_ioctx()
- io_submit_one()

Signed-off-by: Adrian Bunk 
Cc: Zach Brown 
Cc: Benjamin LaHaise 
Cc: Badari Pulavarty 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

aio: io_getevents() should return if io_destroy() is invoked

2008-04-28T15:58:17+00:00

This patch wakes up a thread waiting in io_getevents if another thread
destroys the context.  This was tested using a small program that spawns a
thread to wait in io_getevents while the parent thread destroys the io context
and then waits for the getevents thread to exit.  Without this patch, the
program hangs indefinitely.  With the patch, the program exits as expected.

Signed-off-by: Jeff Moyer 
Cc: Zach Brown 
Cc: Christopher Smith 
Cc: Benjamin LaHaise 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

eventfd/kaio integration fix

2008-04-11T15:06:43+00:00

Jeff Roberson discovered a race when using kaio eventfd based notifications.
When it occurs it can lead tomissed wakeups and hung userspace.

This patch fixes the race by moving the notification inside the spinlocked
section of kaio.  The operation is safe since eventfd spinlock and kaio one
are unrelated.

Signed-off-by: Davide Libenzi 
Cc: Zach Brown 
Cc: Jeff Roberson 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

asmlinkage_protect sys_io_getevents

2008-04-11T00:28:26+00:00

Use asmlinkage_protect in sys_io_getevents, because GCC for i386 with
CONFIG_FRAME_POINTER=n can decide to clobber an argument word on the
stack, i.e. the user struct pt_regs.  Here the problem is not a tail
call, but just the compiler's use of the stack when it inlines and
optimizes the body of the called function.  This seems to avoid it.

Signed-off-by: Roland McGrath 
Signed-off-by: Linus Torvalds