The discard ioctl is used by mkfs utilities to clear a block device
prior to putting metadata down.  However, not all devices return zeroed
blocks after a discard.  Some drives return stale data, potentially
containing old superblocks.  It is therefore important to know whether
discarded blocks are properly zeroed.

Both ATA and SCSI drives have configuration bits that indicate whether
zeroes are returned after a discard operation.  Implement a block level
interface that allows this information to be bubbled up the stack and
queried via a new block device ioctl.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Not all users of the topology information want to use libblkid.  Provide
the topology information through bdev ioctls.

Also clarify sector size comments for existing BLK ioctls.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Convert all external users of queue limits to using wrapper functions
instead of poking the request queue variables directly.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Though one can specify '-d /dev/sda1' when using blktrace, it still
traces the whole sda.

To support per-partition tracing, when we start tracing, we initialize
bt->start_lba and bt->end_lba to the start and end sector of that
partition.

Note some actions are per device, thus we don't filter 0-sector events.

The original patch and discussion can be found here:
	http://marc.info/?l=linux-btrace&m=122949374214540&w=2Signed-off-by: NShawn Du <duyuyang@gmail.com>
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
LKML-Reference: <49E42620.4050701@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There's no need to take queue_lock or kernel_lock when modifying
bdi->ra_pages. So remove them. Also remove out of date comment for
queue_max_sectors_store().
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Update FMODE_NDELAY before each ioctl call so that we can kill the
magic FMODE_NDELAY_NOW.  It would be even better to do this directly
in setfl(), but for that we'd need to have FMODE_NDELAY for all files,
not just block special files.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Commit 33c2dca4 (trim file propagation
in block/compat_ioctl.c) removed the handling of some ioctls from
compat_blkdev_driver_ioctl.  That caused them to be rejected as unknown
by the compat layer.
Signed-off-by: NAndreas Schwab <schwab@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Variable 'ret' is no longer used. Don't declare it.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now we can switch blkdev_ioctl() block_device/mode
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Most of that stuff doesn't need BKL at all; expand in the (only) caller,
merge the switch into one there and leave BKL only around the stuff that
might actually need it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and remove the handling of cases when it falls back to native
without changing arguments.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

To keep the size of changesets sane we split the switch by drivers;
to keep the damn thing bisectable we do the following:
	1) rename the affected methods, add ones with correct
prototypes, make (few) callers handle both.  That's this changeset.
	2) for each driver convert to new methods.  *ALL* drivers
are converted in this series.
	3) kill the old (renamed) methods.

Note that it _is_ a flagday; all in-tree drivers are converted and by the
end of this series no trace of old methods remain.  The only reason why
we do that this way is to keep the damn thing bisectable and allow per-driver
debugging if anything goes wrong.

New methods:
	open(bdev, mode)
	release(disk, mode)
	ioctl(bdev, mode, cmd, arg)		/* Called without BKL */
	compat_ioctl(bdev, mode, cmd, arg)
	locked_ioctl(bdev, mode, cmd, arg)	/* Called with BKL, legacy */
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We may well want mkfs tools to use this to mark the whole device as
unwanted before they format it, for example.

The ioctl takes a pair of uint64_ts, which are start offset and length
in _bytes_. Although at the moment it might make sense for them both to
be in 512-byte sectors, I don't want to limit the ABI to that.
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

bdevname() fills the buffer that it is given as a parameter, so calling
strcpy() or snprintf() on the returned value is redundant (and probably not
guaranteed to work - I don't think strcpy and snprintf support overlapping
buffers.)
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

hdparm explicitely marks HDIO_[UNREGISTER,SCAN]_HWIF ioctls as DANGEROUS
and given the number of bugs we can assume that there are no real users:

* DMA has no chance of working because DMA resources are released by
  ide_unregister() and they are never allocated again.

* Since ide_init_hwif_ports() is used for ->io_ports[] setup the ioctls
  don't work for almost all hosts with "non-standard" (== non ISA-like)
  layout of IDE taskfile registers (there is a lot of such host drivers).

* ide_port_init_devices() is not called when probing IDE devices so:
  - drive->autotune is never set and IDE host/devices are not programmed
    for the correct PIO/DMA transfer modes (=> possible data corruption)
  - host specific I/O 32-bit and IRQ unmasking settings are not applied
    (=> possible data corruption)
  - host specific ->port_init_devs method is not called (=> no luck with
    ht6560b, qd65xx and opti621 host drivers)

* ->rw_disk method is not preserved (=> no HPT3xxN chipsets support).

* ->serialized flag is not preserved (=> possible data corruption when
   using icside, aec62xx (ATP850UF chipset), cmd640, cs5530, hpt366
   (HPT3xxN chipsets), rz1000, sc1200, dtc2278 and ht6560b host drivers).

* ->ack_intr method is not preserved (=> needed by ide-cris, buddha,
  gayle and macide host drivers).

* ->sata_scr[] and sata_misc[] is cleared by ide_unregister() and it
  isn't initialized again (SiI3112 support needs them).

* To issue an ioctl() there need to be at least one IDE device present
  in the system.

* ->cable_detect method is not preserved + it is not called when probing
  IDE devices so cable detection is broken (however since DMA support is
  also broken it doesn't really matter ;-).

* Some objects which may have already been freed in ide_unregister()
  are restored by ide_hwif_restore() (i.e. ->hwgroup).

* ide_register_hw() may unregister unrelated IDE ports if free ide_hwifs[]
  slot cannot be found.

* When IDE host drivers are modular unregistered port may be re-used by
  different host driver that owned it first causing subtle bugs.

Since we now have a proper warm-plug support remove these ioctls,
then remove no longer needed:
- ide_register_hw() and ide_hwif_restore() functions
- 'init_default' and 'restore' arguments of ide_unregister()
- zeroeing of hwif->{dma,extra}_* fields in ide_unregister()

As an added bonus IDE core code size shrinks by ~3kB (x86-32).

v2:
* fix ide_unregister() arguments in cleanup_module() (Andrew Morton).

v3:
* fix ide_unregister() arguments in palm_bk3710.c.
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Since the SCSI layer uses the request queues from the block layer, blktrace can
also be used to trace the requests to all SCSI devices (like SCSI tape drives),
not only disks. The only missing part is the ioctl interface to start and stop
tracing.

This patch adds the SETUP, START, STOP and TEARDOWN ioctls from blktrace to the
sg device files. With this change, blktrace can be used for SCSI devices like
for disks, e.g.: blktrace -d /dev/sg1 -o - | blkparse -i -
Signed-off-by: NChristof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

The conversion of handlers to compat_blkdev_ioctl accidentally
disabled handling of most ioctl numbers on block devices because
of a typo. Fix the one line to enable it all again.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <axboe@carl.home.kernel.dk>

The floppy ioctls are used by multiple drivers, so they should be
handled in a shared location. Also, add minor cleanups.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

These are shared by all cd-rom drivers and should have common
handlers. Do slight cosmetic cleanups in the process.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

BLKPG is common to all block devices, so it should be handled
by common code.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

These are common to multiple block drivers, so they should
be handled by the block layer.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

blk_trace_setup is broken on x86_64 compat systems,
this makes the code work correctly on all 64 bit architectures
in compat mode.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Handle those blockdev ioctl calls that are compatible
directly from the compat_blkdev_ioctl() function, instead
of having to go through the compat_ioctl hash lookup.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Make compat_blkdev_ioctl and blkdev_ioctl reflect the respective
native versions. This is somewhat more efficient and makes it easier
to keep the two in sync.

Also get rid of the bogus handling for broken_blkgetsize and the
duplicate entry for BLKRASET.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>