tree b842e5e92825d85fae63afadf4fcb4c1a681c28c
parent 673c0c00382ed807f09d94e806f3519ddeeb4f70
author Alan Cox <alan@redhat.com> 1224133367 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1224181298 -0700

i2o: Fix 32/64bit DMA locking

The I2O ioctls assume 32bits.  In itself that is fine as they are old
cards and nobody uses 64bit.  However on LKML it was noted this
assumption is also made for allocated memory and is unsafe on 64bit
systems.

Fixing this is a mess.  It turns out there is tons of crap buried in a
header file that does racy 32/64bit filtering on the masks.

So we:
- Verify all callers of the racy code can sleep (i2o_dma_[re]alloc)
- Move the code into a new i2o/memory.c file
- Remove the gfp_mask argument so nobody can try and misuse the function
- Wrap a mutex around the problem area (a single mutex is easy to do and
  none of this is performance relevant)
- Switch the remaining problem kmalloc holdout to use i2o_dma_alloc

Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Vasily Averin <vvs@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>