linux.git/drivers/block/floppy.c, branch v2.6.38

Fix over-zealous flush_disk when changing device size.

2011-02-24T06:25:47+00:00

There are two cases when we call flush_disk.
In one, the device has disappeared (check_disk_change) so any
data will hold becomes irrelevant.
In the oter, the device has changed size (check_disk_size_change)
so data we hold may be irrelevant.

In both cases it makes sense to discard any 'clean' buffers,
so they will be read back from the device if needed.

In the former case it makes sense to discard 'dirty' buffers
as there will never be anywhere safe to write the data.  In the
second case it *does*not* make sense to discard dirty buffers
as that will lead to file system corruption when you simply enlarge
the containing devices.

flush_disk calls __invalidate_devices.
__invalidate_device calls both invalidate_inodes and invalidate_bdev.

invalidate_inodes *does* discard I_DIRTY inodes and this does lead
to fs corruption.

invalidate_bev *does*not* discard dirty pages, but I don't really care
about that at present.

So this patch adds a flag to __invalidate_device (calling it
__invalidate_device2) to indicate whether dirty buffers should be
killed, and this is passed to invalidate_inodes which can choose to
skip dirty inodes.

flusk_disk then passes true from check_disk_change and false from
check_disk_size_change.

dm avoids tripping over this problem by calling i_size_write directly
rathher than using check_disk_size_change.

md does use check_disk_size_change and so is affected.

This regression was introduced by commit 608aeef17a which causes
check_disk_size_change to call flush_disk, so it is suitable for any
kernel since 2.6.27.

Cc: stable@kernel.org
Acked-by: Jeff Moyer 
Cc: Andrew Patterson 
Cc: Jens Axboe 
Signed-off-by: NeilBrown

Merge branch 'for-2.6.38/drivers' of git://git.kernel.dk/linux-2.6-block

2011-01-13T18:50:24+00:00

* 'for-2.6.38/drivers' of git://git.kernel.dk/linux-2.6-block:
  cciss: reinstate proper FIFO order of command queue list
  floppy: replace NO_GEOM macro with a function

floppy: don't use flush_scheduled_work()

2010-12-24T14:59:06+00:00

flush_scheduled_work() is deprecated and scheduled to be removed.
Directly flush floppy_work instead.

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

floppy: replace NO_GEOM macro with a function

2010-11-08T13:44:34+00:00

This patch replaces the NO_GEOM macro with a proper static inline function and
converts an open-coded caller in check_floppy_change() to use it.

Cc: Stephen Hemminger 
Cc: Andrew Morton 
Signed-off-by: Pekka Enberg 
Signed-off-by: Jens Axboe

floppy: fix another use-after-free

2010-11-06T14:49:56+00:00

While scanning the floopy code due to c093ee4f07f4 ("floppy: fix
use-after-free in module load failure path"), I found one more instance
of trying to access disk->queue pointer after doing put_disk() on
gendisk.  For some reason , floppy moule still loads/unloads fine.  The
object is probably still around with right pointer values.

 o There seems to be one more instance of trying to cleanup the request
   queue after we have called put_disk() on associated gendisk.

 o This fix is more out of code inspection.  Even without this fix for
   some reason I am able to load/unload floppy module without any
   issues.

 o Floppy module loads/unloads fine after the fix.

Signed-off-by: Vivek Goyal 
Signed-off-by: Linus Torvalds

floppy: fix use-after-free in module load failure path

2010-11-06T00:45:59+00:00

Commit 488211844e0c ("floppy: switch to one queue per drive instead of
sharing a queue") introduced a use-after-free.  We do "put_disk()" on
the disk device _before_ we then clean up the queue associated with that
disk.

Move the put_disk() down to avoid dereferencing a free'd data structure.

Cc: Jens Axboe 
Cc: Vivek Goyal 
Reported-and-tested-by: Randy Dunlap 
Signed-off-by: Linus Torvalds

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

floppy: switch to one queue per drive instead of sharing a queue

2010-09-22T07:32:36+00:00

Pretty straight forward conversion. Note that we do round-robin
between the drives that have available requests, before we simply
used the drive that the IO scheduler told us to. Since the IO
scheduler doesn't care about multiple devices per queue, the resulting
sort would not have made sense.

Fixed by Vivek to get rid of a double lock problem in set_next_request()

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

floppy: make controller const

2010-08-07T16:52:31+00:00

The struct cont_t is just a set of virtual function pointers.

Signed-off-by: Stephen Hemminger 
Signed-off-by: Andrew Morton 
Signed-off-by: Jens Axboe