linux-stable.git/drivers/block/ataflop.c, branch linux-3.2.y

block: unexport DISK_EVENT_MEDIA_CHANGE for legacy/fringe drivers

2011-04-21T19:33:05+00:00

In-kernel disk event polling doesn't matter for legacy/fringe drivers
and may lead to infinite event loop if ->check_events() implementation
generates events on level condition instead of edge.

Now that block layer supports suppressing exporting unlisted events,
simply leaving disk->events cleared allows these drivers to keep the
internal revalidation behavior intact while avoiding weird
interactions with userland event handler.

Signed-off-by: Tejun Heo 
Cc: Kay Sievers 
Signed-off-by: Jens Axboe

floppy,{ami|ata}flop: Convert to bdops->check_events()

2011-03-09T18:54:27+00:00

Convert the floppy drivers from ->media_changed() to ->check_events().
Both floppy and ataflop buffer media changed state bit and clear them
on revalidation and will behave correctly with kernel event polling.

I can't tell how amiflop clears its event and it's possible that it
may generate spurious events when polled.

Signed-off-by: Tejun Heo 
Cc: Jens Axboe 
Cc: Kay Sievers

block: fix amiga and atari floppy driver compile warning

2010-11-15T18:32:43+00:00

Geert, my crosstool don't produce warning below. I guess this has to do
something with compiler version.

- Geert noticed following warning during compilation.

  drivers/block/amiflop.c:1344: warning: ‘rq’ may be used uninitialized in
  this function
  drivers/block/ataflop.c:1402: warning: ‘rq’ may be used uninitialized in
  this function

- Initialize rq to NULL to fix the warning. If we can't find a suitable request
  to dispatch, this function should return NULL instead of a possibly garbage
  pointer.

- Cross compile tested only. Don't have hardware to test it.

Reported-by: Geert Uytterhoeven 
Signed-off-by: Vivek Goyal 
Signed-off-by: Jens Axboe

Merge branch 'for-2.6.37/drivers' of git://git.kernel.dk/linux-2.6-block

2010-10-23T00:03:12+00:00

* 'for-2.6.37/drivers' of git://git.kernel.dk/linux-2.6-block: (95 commits)
  cciss: fix PCI IDs for new Smart Array controllers
  drbd: add race-breaker to drbd_go_diskless
  drbd: use dynamic_dev_dbg to optionally log uuid changes
  dynamic_debug.h: Fix dynamic_dev_dbg() macro if CONFIG_DYNAMIC_DEBUG not set
  drbd: cleanup: change "<= 0" to "== 0"
  drbd: relax the grace period of the md_sync timer again
  drbd: add some more explicit drbd_md_sync
  drbd: drop wrong debug asserts, fix recently introduced race
  drbd: cleanup useless leftover warn/error printk's
  drbd: add explicit drbd_md_sync to drbd_resync_finished
  drbd: Do not log an ASSERT for P_OV_REQUEST packets while C_CONNECTED
  drbd: fix for possible deadlock on IO error during resync
  drbd: fix unlikely access after free and list corruption
  drbd: fix for spurious fullsync (uuids rotated too fast)
  drbd: allow for explicit resync-finished notifications
  drbd: preparation commit, using full state in receive_state()
  drbd: drbd_send_ack_dp must not rely on header information
  drbd: Fix regression in recv_bm_rle_bits (compressed bitmap)
  drbd: Fixed a stupid copy and paste error
  drbd: Allow larger values for c-fill-target.
  ...

Fix up trivial conflict in drivers/block/ataflop.c due to BKL removal

block: autoconvert trivial BKL users to private mutex

2010-10-05T13:01:10+00:00

The block device drivers have all gained new lock_kernel
calls from a recent pushdown, and some of the drivers
were already using the BKL before.

This turns the BKL into a set of per-driver mutexes.
Still need to check whether this is safe to do.

file=$1
name=$2
if grep -q lock_kernel ${file} ; then
    if grep -q 'include.*linux.mutex.h' ${file} ; then
            sed -i '/include.*/d' ${file}
    else
            sed -i 's/include.*.*$/include /g' ${file}
    fi
    sed -i ${file} \
        -e "/^#include.*linux.mutex.h/,$ {
                1,/^\(static\|int\|long\)/ {
                     /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);

} }"  \
    -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
    -e '/[      ]*cycle_kernel_lock();/d'
else
    sed -i -e '/include.*\/d' ${file}  \
                -e '/cycle_kernel_lock()/d'
fi

Signed-off-by: Arnd Bergmann

atari floppy: Stop sharing request queue across multiple gendisks

2010-09-24T18:35:45+00:00

o Use one request queue per gendisk instead of sharing the queue.

o Don't have hardware. No compile testing or run time testing done. Completely
  untested.

Signed-off-by: Vivek Goyal 
Signed-off-by: Jens Axboe

block: push down BKL into .open and .release

2010-08-07T16:25:34+00:00

The open and release block_device_operations are currently
called with the BKL held. In order to change that, we must
first make sure that all drivers that currently rely
on this have no regressions.

This blindly pushes the BKL into all .open and .release
operations for all block drivers to prepare for the
next step. The drivers can subsequently replace the BKL
with their own locks or remove it completely when it can
be shown that it is not needed.

The functions blkdev_get and blkdev_put are the only
remaining users of the big kernel lock in the block
layer, besides a few uses in the ioctl code, none
of which need to serialize with blkdev_{get,put}.

Most of these two functions is also under the protection
of bdev->bd_mutex, including the actual calls to
->open and ->release, and the common code does not
access any global data structures that need the BKL.

Signed-off-by: Arnd Bergmann 
Acked-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

block: push down BKL into .locked_ioctl

2010-08-07T16:25:00+00:00

As a preparation for the removal of the big kernel
lock in the block layer, this removes the BKL
from the common ioctl handling code, moving it
into every single driver still using it.

Signed-off-by: Arnd Bergmann 
Acked-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

ataflop: Killl warning about unused variable flags

2010-02-27T17:27:15+00:00

After commit e0c0978699a83f26f2341f7eedc1463b79e31aff ("ataflop: remove
buggy/commented-out IRQ disable from do_fd_request()") the `flags' variable
became unused:

drivers/block/ataflop.c:1473: warning: unused variable 'flags'

Hence remove it.

Signed-off-by: Geert Uytterhoeven

ataflop: remove buggy/commented-out IRQ disable from do_fd_request()

2009-11-09T08:40:57+00:00

There is a nice gem in drivers/block/ataflop.c::do_fd_request()

      void do_fd_request(struct request_queue * q)
      {
              unsigned long flags;

              DPRINT(("do_fd_request for pid %d\n",current->pid));
              while( fdc_busy ) sleep_on( &fdc_wait );
              fdc_busy = 1;
              stdma_lock(floppy_irq, NULL);

              atari_disable_irq( IRQ_MFP_FDC );
              local_save_flags(flags);        /* The request function is called with ints
              local_irq_disable();             * disabled... so must save the IPL for later */
              redo_fd_request();
              local_irq_restore(flags);
              atari_enable_irq( IRQ_MFP_FDC );
      }

If you look at the code long enough, you will notioce that the
local_irq_disable() call is actually commented out. This has been
introduced back in 2002 in [1], but as you can see, the same bug has been
there even before, with the sti() call being commented out in the very
same way :)

I am not familiar with the code myself at all, but I guess that the whole
stuff can just be removed. Why do we need save_flags/restore_flags at all,
without actually disabling the local IRQs afterwards? The
redo_fd_request() doesn't seem to do anything that would mess with flags
inconsistently.

[1] http://lkml.org/lkml/2002/12/27/58

Jens:
That does look odd. The comment is correct that the function is entered
with interrupts disabled (and the queue lock held). So I'd say your
patch looks fine, the whole save/restore business looks meaningless.

Signed-off-by: Jiri Kosina 
Acked-by: Jens Axboe 
Acked-by: Michael Schmitz