s390/dasd: move wake_up call

Ensure that all work is done when the process waiting for a
dasd state change is woken up. With this change it is save
to assume that after a userspace t

s390/dasd: move wake_up call

Ensure that all work is done when the process waiting for a
dasd state change is woken up. With this change it is save
to assume that after a userspace triggered state change and
a udev settle invocation there are no unexpected users of a
dasd device.

Acked-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/comments: unify copyright messages and remove file names

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather poi

s390/comments: unify copyright messages and remove file names

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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s390/dasd: add shutdown action

Add a mechanism to wait for outstanding IO during shutdown.
Schedule the block_bh and device_bh and wait until our request queues
are empty.

S

s390/dasd: add shutdown action

Add a mechanism to wait for outstanding IO during shutdown.
Schedule the block_bh and device_bh and wait until our request queues
are empty.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] dasd: prevent validate server for offline devices

Calling validate server on devices in offline processing may cause
an OOPS in the dasd_sleep_on function.

Signed-off-by:

[S390] dasd: prevent validate server for offline devices

Calling validate server on devices in offline processing may cause
an OOPS in the dasd_sleep_on function.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Reviewed-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: revalidate server for new pathgroup

If a pathgroup is established we get an event and have to revalidate
the server to propagate supported features like PAV and enable them.

[S390] dasd: revalidate server for new pathgroup

If a pathgroup is established we get an event and have to revalidate
the server to propagate supported features like PAV and enable them.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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Merge branches 'vfsmount-guts', 'umode_t' and 'partitions' into Z

switch debugfs to umode_t

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

fs: move code out of buffer.c

Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export
kill_bdev as well, so brd doesn't have to open code it. Reduce
buffer_head.h require

fs: move code out of buffer.c

Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export
kill_bdev as well, so brd doesn't have to open code it. Reduce
buffer_head.h requirement accordingly.

Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving. The small comment replacing it says enough.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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[S390] dasd: prevent path verification before resume

Mark the device as suspended and delay execution of the path
verification worker to prevent mix-up.

Signed-off-by: Stefan Ha

[S390] dasd: prevent path verification before resume

Mark the device as suspended and delay execution of the path
verification worker to prevent mix-up.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: re-initialize read_conf buffer for retries

The buffer for read configuration data has to be initialized with an
EBCDIC string to show support for extended UIDs to z/VM.

[S390] dasd: re-initialize read_conf buffer for retries

The buffer for read configuration data has to be initialized with an
EBCDIC string to show support for extended UIDs to z/VM.
If this read configuration data CQR needs to be retried, the buffer
may have changed in between. So re-initialize the buffer to get a
correct extended UID under z/VM.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: wait for terminated request

After terminating a request in the dasd_sleep_on_immediatly function,
wait for the clear interrupt to be received before starting the
new req

[S390] dasd: wait for terminated request

After terminating a request in the dasd_sleep_on_immediatly function,
wait for the clear interrupt to be received before starting the
new request. This prevents the requests from getting mixed up.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] fix mismatch in summation of I/O IRQ statistics

Current IRQ statistics support does not show detail counts for I/O
interrupts which are processed internally only. The result is a

[S390] fix mismatch in summation of I/O IRQ statistics

Current IRQ statistics support does not show detail counts for I/O
interrupts which are processed internally only. The result is a
summation count which is way off such as this one:

CPU0 CPU1 CPU2
I/O: 1331 710 442
[...]
QAI: 15 16 16 [I/O] QDIO Adapter Interrupt
QDI: 1 0 0 [I/O] QDIO Interrupt
DAS: 706 645 381 [I/O] DASD
C15: 26 10 0 [I/O] 3215
C70: 0 0 0 [I/O] 3270
TAP: 0 0 0 [I/O] Tape
VMR: 0 0 0 [I/O] Unit Record Devices
LCS: 0 0 0 [I/O] LCS
CLW: 0 0 0 [I/O] CLAW
CTC: 0 0 0 [I/O] CTC
APB: 0 0 0 [I/O] AP Bus

Fix this by moving I/O interrupt accounting into the common I/O layer.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: use vmalloc for statistics input buffer

The size of the buffer that is used to store DASD statistics input
strings depends on the user input. If the input string is to large

[S390] dasd: use vmalloc for statistics input buffer

The size of the buffer that is used to store DASD statistics input
strings depends on the user input. If the input string is to large,
the write operation could fail with -ENOMEM. To avoid this, use
vmalloc instead of kmalloc.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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[S390] dasd: add enhanced DASD statistics interface

This patch extends the DASD statistics to allow for a more detailed
analysis of DASD I/O operations. In particular we want the statist

[S390] dasd: add enhanced DASD statistics interface

This patch extends the DASD statistics to allow for a more detailed
analysis of DASD I/O operations. In particular we want the statistics
to provide answers to the following questions:
- How many requests used a PAV alias?
- How many requests used High Performance FICON?
- How do read request perform versus write requests?

The existing DASD statistics interface has several shortcomings
- The interface for global data is a formatted text table in procfs
(/proc/dasd/statistics). The layout is meant for human readers and
is not to easy to parse. If values get to large for the table
layout, they get scaled down.
- The statistics which are collected per block device can be
accessed via an ioctl interface, which can only be extended by
defining a new ioctl.
- There is no statistics interface for individual PAV base and alias
devices.

To overcome theses shortcomings we create a new DASD statistics
interface in debugfs. This interface will contain one entry for global
data, one per DASD block device, and one per DASD base and alias
device. Each file contains the statistic data in easy to parse
name/value and name/array pairs. The existing interfaces will remain
functional, but they will not be extended.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: prevent IO error during reserve/release loop

The termination of running CQR caused by reserve/release operations
may lead to an IO error if reserve/release is done in a tigh

[S390] dasd: prevent IO error during reserve/release loop

The termination of running CQR caused by reserve/release operations
may lead to an IO error if reserve/release is done in a tight loop.
Prevent this by increasing the retry counter after termination.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: fix race between open and offline

The dasd_open function uses the private_data pointer of the gendisk to
find the dasd_block structure that matches the gendisk. When a DASD

[S390] dasd: fix race between open and offline

The dasd_open function uses the private_data pointer of the gendisk to
find the dasd_block structure that matches the gendisk. When a DASD
device is set offline, we set the private_data pointer of the gendisk
to NULL and later remove the dasd_block structure, but there is still
a small race window, in which dasd_open could first read a pointer
from the private_data field and then try to use it, after the structure
has already been freed.
To close this race window, we will store a pointer to the dasd_devmap
structure of the base device in the private_data field. The devmap
entries are not deleted, and we already have proper locking and
reference counting in place, so that we can safely get from a devmap
pointer to the dasd_device and dasd_block structures of the device.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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block: remove per-queue plugging

Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off

block: remove per-queue plugging

Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

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[S390] dasd: Correct retry counter for terminated I/O.

In case the DASD driver needs to term a running I/O the retry counter
is decreased twice.
Remove the unnecessary retry counter

[S390] dasd: Correct retry counter for terminated I/O.

In case the DASD driver needs to term a running I/O the retry counter
is decreased twice.
Remove the unnecessary retry counter decrease in das_term_IO.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: Add support for raw ECKD access.

Normal I/O operations through the DASD device driver give only access
to the data fields of an ECKD device even for track based I/O.
Thi

[S390] dasd: Add support for raw ECKD access.

Normal I/O operations through the DASD device driver give only access
to the data fields of an ECKD device even for track based I/O.
This patch extends the DASD device driver to give access to whole
ECKD tracks including count, key and data fields.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: Prevent deadlock during suspend/resume.

The freeze callback may set a stop bit so that a worker thread could
not start I/O. The discipline specific freeze function waits for

[S390] dasd: Prevent deadlock during suspend/resume.

The freeze callback may set a stop bit so that a worker thread could
not start I/O. The discipline specific freeze function waits for the
worker to be completed.
Set the stop_bit after the discipline specific freeze function has
returned and no worker is running.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: Improve handling of stolen DASD reservation

If a DASD device has been reserved by a Linux system, and later
this reservation is ‘stolen’ by a second system by means of an

[S390] dasd: Improve handling of stolen DASD reservation

If a DASD device has been reserved by a Linux system, and later
this reservation is ‘stolen’ by a second system by means of an
unconditional reserve, then the first system receives a
notification about this fact. With this patch such an event can
be either ignored, as before, or it can be used to let the device
fail all I/O request, so that the device will not block anymore.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: do path verification for paths added at runtime

When a new path is added at runtime, the CIO layer will call the drivers
path_event callback. The DASD device driver uses thi

[S390] dasd: do path verification for paths added at runtime

When a new path is added at runtime, the CIO layer will call the drivers
path_event callback. The DASD device driver uses this callback to trigger
a path verification for the new path. The driver will use only those
paths for I/O, which have been successfully verified.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: add High Performance FICON multitrack support

Some storage systems support multitrack High Performance FICON
requests, which read or write data to more than one track.
T

[S390] dasd: add High Performance FICON multitrack support

Some storage systems support multitrack High Performance FICON
requests, which read or write data to more than one track.
This patch enables the DASD device driver to generate multitrack
High Performance FICON requests.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: add support for irq statistics

Add support for DASD I/O interrupt statistics in /proc/interrupts.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-o

[S390] dasd: add support for irq statistics

Add support for DASD I/O interrupt statistics in /proc/interrupts.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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[S390] dasd: ignore unsolicited interrupts for DIAG

For the DASD DIAG discipline IO is started through special diagnose
calls. Unsolicited interrupts may contain information about the de

[S390] dasd: ignore unsolicited interrupts for DIAG

For the DASD DIAG discipline IO is started through special diagnose
calls. Unsolicited interrupts may contain information about the device
itself. But this information is not needed because the device is not
used directly.
Fix the case that an unimplemented dicipline function may be called
by ignoring unsolicited interrupts for the DIAG disciplin.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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