s390/cio,idal: fix virtual vs physical address confusion

Fix virtual vs physical address confusion. This does not fix a bug since
virtual and physical address spaces are currently the same.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/dasd: use new address translation helpers

Use virt_to_dma32() and friends to properly convert virtual to physical and
physical to virtual addresses so that "make C=1" does not generate any
warnings anymore.

Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/dasd: remove superfluous virt_to_phys() conversion

Only the last 12 bits of virtual / physical addresses are used when masking
with IDA_BLOCK_SIZE - 1. Given that the bits are the same regardless of
virtual or physical address, remove the virtual to physical address
conversion.

Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/dasd_eckd: fix virtual vs physical address confusion

Fix virtual vs physical address confusion. This does not fix a bug
since virtual and physical address spaces are currently the same.

Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

dasd: move queue setup to common code

Most of the code in setup_blk_queue is shared between all disciplines.
Move it to common code and leave a method to query the maximum number
of transferable blocks, and a flag to indicate discard support.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20240228133742.806274-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Remove PRINTK_HEADER and KMSG_COMPONENT definitions

PRINTK_HEADER was mainly used to prefix log messages with the module
name. Most components don't use this definition anymore. Either because
there are no log messages being generated anymore, or pr_*() were
replaced by dev_*(), which contains device and component information
already.

PRINTK_HEADER is also dropped in the function
dasd_3990_erp_handle_match_erp() in dasd_3990_erp.c from a panic() call
as panic() already provides all relevant information.

KMSG_COMPONENT was mainly used to identify a component in a long gone
kernel message catalog feature.

Remove both definition since they're either not used or alternatives
make the code slightly shorter and more readable.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20240208164248.540985-9-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Use dev_err() over printk()

To reduce the information required for the string generation in the
sense dump functions, use the more concise dev_err() variant over
printk(KERN_ERR, ...) to improve code readability.

The dev_err() function provides the component and device name for free
and the separate dev_name() calls as well as the PRINTK_HEADER can be
dropped.

Dropping PRINTK_HEADER removes the "dasd(eckd):" for all lines. Only the
first line of a dev_err() call is prefixed with the component and device
(e.g. "dasd-eckd 0.0.95d0:").

The format specifier for printed pointers is also changed to unhashed
(%px) as this can help with debugging and servicing.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20240208164248.540985-7-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Simplify uid string generation

There are two variants of the device uid string. One containing the
virtual device unit information table (vduit) identifying the device as
a virtual device located on a real device in a z/VM environment. The
other variant does not contain those additional information.

Simplify the string generation with a shorter check of an existing vduit
embedded in the snprintf() calls.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20240208164248.540985-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix string length handling

Building dasd_eckd.o with latest clang reveals this bug:

CC drivers/s390/block/dasd_eckd.o
drivers/s390/block/dasd_eckd.c:1082:3: warning: 'snprintf' will always be truncated;
specified size is 1, but format string expands to at least 11 [-Wfortify-source]
1082 | snprintf(print_uid, sizeof(*print_uid),
| ^
drivers/s390/block/dasd_eckd.c:1087:3: warning: 'snprintf' will always be truncated;
specified size is 1, but format string expands to at least 10 [-Wfortify-source]
1087 | snprintf(print_uid, sizeof(*print_uid),
| ^

Fix this by moving and using the existing UID_STRLEN for the arrays
that are being written to. Also rename UID_STRLEN to DASD_UID_STRLEN
to clarify its scope.

Fixes: 23596961b437 ("s390/dasd: split up dasd_eckd_read_conf")
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com> # build
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://github.com/ClangBuiltLinux/linux/issues/1923
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20230828153142.2843753-2-hca@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390: include linux/io.h instead of asm/io.h

Include linux/io.h instead of asm/io.h everywhere. linux/io.h includes
asm/io.h, so this shouldn't cause any problems. Instead this might help for
some randconfig build errors which were reported due to some undefined io
related functions.

Also move the changed include so it stays grouped together with other
includes from the same directory.

For ctcm_mpc.c also remove not needed comments (actually questions).

Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

s390/dasd: fix command reject error on ESE devices

Formatting a thin-provisioned (ESE) device that is part of a PPRC copy
relation might fail with the following error:

dasd-eckd 0.0.f500: An error occurred in the DASD device driver, reason=09
[...]
24 Byte: 0 MSG 4, no MSGb to SYSOP

During format of an ESE disk the Release Allocated Space command is used.
A bit in the payload of the command is set that is not allowed to be set
for devices in a copy relation. This bit is set to allow the partial
release of an extent.

Check for the existence of a copy relation before setting the respective
bit.

Fixes: 91dc4a197569 ("s390/dasd: Add new ioctl to release space")
Cc: stable@kernel.org # 5.3+
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20230519102340.3854819-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: add aq_timeouts autoquiesce trigger

Add a sysfs attribute aq_timeouts that controls after how many
timeouts a autoquiesce event might be triggered.

The default value is 32768 which is the maximum number of retries
for the DASD device driver DASD_RETRIES_MAX. This means that the
timeout trigger will never happen.

The default value for DASD retries is 255.
Setting the value to below 255 will trigger the timeout autoquiesce
event before an IO error is generated.

Also add the check for the configured amount of timeouts and trigger
an autoquiesce event if exceeded.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Link: https://lore.kernel.org/r/20230405142017.2446986-6-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Fix potential memleak in dasd_eckd_init()

`dasd_reserve_req` is allocated before `dasd_vol_info_req`, and it
also needs to be freed before the error returns, just like the other
cases in this function.

Fixes: 9e12e54c7a8f ("s390/dasd: Handle out-of-space constraint")
Signed-off-by: Qiheng Lin <linqiheng@huawei.com>
Link: https://lore.kernel.org/r/20221208133809.16796-1-linqiheng@huawei.com
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20230210000253.1644903-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: sort out physical vs virtual pointers usage

This does not fix a real bug, since virtual addresses
are currently indentical to physical ones.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20230210000253.1644903-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix no record found for raw_track_access

For DASD devices in raw_track_access mode only full track images are
read and written.
For this purpose it is not necessary to do search operation in the
locate record extended function. The documentation even states that
this might fail if the searched record is not found on a track.

Currently the driver sets a value of 1 in the search field for the first
record after record zero. This is the default for disks not in
raw_track_access mode but record 1 might be missing on a completely
empty track.

There has not been any problem with this on IBM storage servers but it
might lead to errors with DASD devices on other vendors storage servers.

Fix this by setting the search field to 0. Record zero is always available
even on a completely empty track.

Fixes: e4dbb0f2b5dd ("[S390] dasd: Add support for raw ECKD access.")
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20221123160719.3002694-4-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: increase printing of debug data payload

32 byte are to less for important data from prefix or
other commands.
Print up to 128 byte data. This is enough for the largest
CCW data we have.

Since printk can only print up to 1024 byte at once, print the
different parts of the CCW dumps separately.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20221123160719.3002694-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: use blk_mq_alloc_disk

As far as I can tell there is no need for the staged setup in
dasd, so allocate the tagset and the disk with the queue in
dasd_gendisk_alloc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20220928143945.1687114-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: add device ping attribute

Add a function to check if a device is accessible.
This makes mostly sense for copy pair secondary devices but it will work
for all devices.

The sysfs attribute ping is a write only attribute and will issue a NOP
CCW to the device.
In case of success it will return zero. If the device is not accessible
it will return an error code.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220920192616.808070-8-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: add copy pair swap capability

In case of errors or misbehaviour of the primary device a controlled
failover to one of the configured secondary devices needs to be
performed.

The swap processing stops I/O on the primary device, all requests are
re-queued to the blocklayer queue, the entries in the copy relation are
swapped and finally the link to the blockdevice is moved from primary to
secondary dasd device.
After this, the secondary becomes the new primary device and I/O is
restarted on that device.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220920192616.808070-5-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: add copy pair setup

A copy relation that is configured on the storage server side needs to be
enabled separately in the device driver. A sysfs interface is created
that allows userspace tooling to control such setup.

The following sysfs entries are added to store and read copy relation
information:

copy_pair
- Add/Delete a copy pair relation to the DASD device driver
- Query all previously added copy pair relations
copy_role
- Query the copy pair role of the device

To add a copy pair to the DASD device driver it has to be specified
through the sysfs attribute copy_pair. Only one secondary device can be
specified at a time together with the primary device. Both, secondary
and primary can be used equally to define the copy pair.
The secondary devices have to be offline when adding the copy relation.
The primary device needs to be specified first followed by the comma
separated secondary device.
Read from the copy_pair attribute to get the current setup and write
"clear" to the attribute to delete any existing setup.

Example:
$ echo 0.0.9700,0.0.9740 > /sys/bus/ccw/devices/0.0.9700/copy_pair
$ cat /sys/bus/ccw/devices/0.0.9700/copy_pair
0.0.9700,0.0.9740

During device online processing the required data will be read from the
storage server and the information will be compared to the setup
requested through the copy_pair attribute. The registration of the
primary and secondary device will be handled accordingly.
A blockdevice is only allocated for copy relation primary devices.

To query the copy role of a device read from the copy_role sysfs
attribute. Possible values are primary, secondary, and none.

Example:
$ cat /sys/bus/ccw/devices/0.0.9700/copy_role
primary

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220920192616.808070-4-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: add query PPRC function

Add function to query the Peer-to-Peer-Remote-Copy (PPRC) state of a
device by reading the related structure through a read subsystem data call.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220920192616.808070-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: put block allocation in separate function

Put block allocation into a separate function to put some copy pair logic
in it in a later patch.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220920192616.808070-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Establish DMA alignment

linux-next commit bf8d08532bc1 ("iomap: add support for dma aligned
direct-io") changes the alignment requirement to come from the block
device rather than the block size, and the default alignment
requirement is 512-byte boundaries. Since DASD I/O has page
alignments for IDAW/TIDAW requests, let's override this value to
restore the expected behavior.

Make this change for both ECKD and DIAG disciplines, as they both
would fall into this category. Leave FBA alone, since it is always
comprised of 512-byte blocks.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20220804213926.3361574-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Use kzalloc instead of kmalloc/memset

Use kzalloc rather than duplicating its implementation, which
makes code simple and easy to understand.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20220505141733.1989450-6-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Fix read for ESE with blksize < 4k

When reading unformatted tracks on ESE devices, the corresponding memory
areas are simply set to zero for each segment. This is done incorrectly
for blocksizes < 4096.

There are two problems. First, the increment of dst is done using the
counter of the loop (off), which is increased by blksize every
iteration. This leads to a much bigger increment for dst as actually
intended. Second, the increment of dst is done before the memory area
is set to 0, skipping a significant amount of bytes of memory.

This leads to illegal overwriting of memory and ultimately to a kernel
panic.

This is not a problem with 4k blocksize because
blk_queue_max_segment_size is set to PAGE_SIZE, always resulting in a
single iteration for the inner segment loop (bv.bv_len == blksize). The
incorrectly used 'off' value to increment dst is 0 and the correct
memory area is used.

In order to fix this for blksize < 4k, increment dst correctly using the
blksize and only do it at the end of the loop.

Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20220505141733.1989450-4-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: prevent double format of tracks for ESE devices

For ESE devices we get an error for write operations on an unformatted
track. Afterwards the track will be formatted and the IO operation
restarted.
When using alias devices a track might be accessed by multiple requests
simultaneously and there is a race window that a track gets formatted
twice resulting in data loss.

Prevent this by remembering the amount of formatted tracks when starting
a request and comparing this number before actually formatting a track
on the fly. If the number has changed there is a chance that the current
track was finally formatted in between. As a result do not format the
track and restart the current IO to check.

The number of formatted tracks does not match the overall number of
formatted tracks on the device and it might wrap around but this is no
problem. It is only needed to recognize that a track has been formatted at
all in between.

Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes")
Cc: stable@vger.kernel.org # 5.3+
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220505141733.1989450-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix data corruption for ESE devices

For ESE devices we get an error when accessing an unformatted track.
The handling of this error will return zero data for read requests and
format the track on demand before writing to it. To do this the code needs
to distinguish between read and write requests. This is done with data from
the blocklayer request. A pointer to the blocklayer request is stored in
the CQR.

If there is an error on the device an ERP request is built to do error
recovery. While the ERP request is mostly a copy of the original CQR the
pointer to the blocklayer request is not copied to not accidentally pass
it back to the blocklayer without cleanup.

This leads to the error that during ESE handling after an ERP request was
built it is not possible to determine the IO direction. This leads to the
formatting of a track for read requests which might in turn lead to data
corruption.

Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes")
Cc: stable@vger.kernel.org # 5.3+
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220505141733.1989450-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix missing path conf_data after failed allocation

dasd_eckd_path_available_action() does a memory allocation to store
the per path configuration data permanently.
In the unlikely case that this allocation fails there is no conf_data
stored for the corresponding path.

This is OK since this is not necessary for an operational path but some
features like control unit initiated reconfiguration (CUIR) do not work.

To fix this add the path to the 'to be verified pathmask' again and
schedule the handler again.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20211020115124.1735254-7-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: summarize dasd configuration data in a separate structure

Summarize the dasd configuration data in a separate structure so that
functions that need temporary config data do not need to allocate the
whole eckd_private structure.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20211020115124.1735254-6-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: move dasd_eckd_read_fc_security

dasd_eckd_read_conf is called multiple times during device setup but the
fc_security feature needs to be read only once. So move it into the calling
function.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20211020115124.1735254-5-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: split up dasd_eckd_read_conf

Move the cabling check out of dasd_eckd_read_conf and split it up into
separate functions to improve readability and re-use functions.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20211020115124.1735254-4-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

dasd: use bvec_virt

Use bvec_virt instead of open coding it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20210804095634.460779-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix use after free in dasd path handling

When new configuration data is obtained after a path event it is stored
in the per path array. The old data needs to be freed.
The first valid configuration data is also referenced in the device
private structure to identify the device.
When the old per path configuration data was freed the device still
pointed to the already freed data leading to a use after free.

Fix by replacing also the device configuration data with the newly
obtained one before the old data gets freed.

Fixes: 460181217a24 ("s390/dasd: Store path configuration data during path handling")
Cc: stable@vger.kernel.org # 5.11+
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Link: https://lore.kernel.org/r/20210804151800.4031761-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Avoid field over-reading memcpy()

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field array bounds checking for memcpy(), memmove(), and memset(),
avoid intentionally reading across neighboring array fields.

Add a wrapping structure to serve as the memcpy() source, so the compiler
can do appropriate bounds checking, avoiding this future warning:

In function '__fortify_memcpy',
inlined from 'create_uid' at drivers/s390/block/dasd_eckd.c:749:2:
./include/linux/fortify-string.h:246:4: error: call to '__read_overflow2_field' declared with attribute error: detected read beyond size of field (2nd parameter)

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20210701142221.3408680-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: let driver core manage the sysfs attributes

Wire up device_driver->dev_groups, so that really_probe() creates the
sysfs attributes for us automatically.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Link: https://lore.kernel.org/r/20210316094513.2601218-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Fix inconsistent kobject removal

Our intention was to only remove path kobjects whenever a device is
being set offline. However, one corner case was missing.

If a device is disabled and enabled (using the IOCTLs BIODASDDISABLE and
BIODASDENABLE respectively), the enabling process will call
dasd_eckd_reload_device() which itself calls dasd_eckd_read_conf() in
order to update path information. During that update,
dasd_eckd_clear_conf_data() clears all old data and also removes all
kobjects. This will leave us with an inconsistent state of path kobjects
and a subsequent path verification leads to a failing kobject creation.

Fix this by removing kobjects only in the context of offlining a device
as initially intended.

Fixes: 19508b204740 ("s390/dasd: Display FC Endpoint Security information via sysfs")
Reported-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: remove unused pm related functions

The power-management related functions are unused since the
'commit 394216275c7d ("s390: remove broken hibernate / power management
support")'. Remove them from dasd drivers.

Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

s390/dasd: Process FCES path event notification

If the Fibre Channel Endpoint-Security status of a path changes, a
corresponding path event is received from the CIO layer.

Process this event by re-reading the FCES information.

As the information is retrieved for all paths on a single CU in one
call, the internal status can also be updated for all paths and no
processing per path is necessary.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Prepare for additional path event handling

As more path events need to be handled for ECKD the current path
verification infrastructure can be reused. Rename all path verifcation
code to fit the more broadly based task of path event handling and put
the path verification in a new separate function.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Display FC Endpoint Security information via sysfs

Add a new sysfs attribute (fc_security) per device and per operational
channel path. The information of the current FC Endpoint Security state
is received through the CIO layer.

The state of the FC Endpoint Security can be either "Unsupported",
"Authentication", or "Encryption".

For example:
$ cat /sys/bus/ccw/devices/0.0.c600/fc_security
Encryption

If any of the operational paths is in a state different from all
others, the device sysfs attribute will display the additional state
"Inconsistent".

The sysfs attributes per paths are organised in a new directory called
"paths_info" with subdirectories for each path.

/sys/bus/ccw/devices/0.0.c600/paths_info/
├── 0.38
│   └── fc_security
├── 0.39
│   └── fc_security
├── 0.3a
│   └── fc_security
└── 0.3b
└── fc_security

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Fix operational path inconsistency

During online processing and setting up a DASD device, the configuration
data for operational paths is read and validated two times
(dasd_eckd_read_conf()). The first time to provide information that are
necessary for the LCU setup. A second time after the LCU setup as a
device might report different configuration data then.

When the configuration setup for each operational path is being
validated, an initial call to dasd_eckd_clear_conf_data() is issued.
This call wipes all previously available configuration data and path
information for each path.
However, the operational path mask is not updated during this process.

As a result, the stored operational path mask might no longer correspond
to the operational paths mask reported by the CIO layer, as several
paths might be gone between the two dasd_eckd_read_conf() calls.

This inconsistency leads to more severe issues in later path handling
changes. Fix this by removing the channel paths from the operational
path mask during the dasd_eckd_clear_conf_data() call.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Store path configuration data during path handling

Currently, the configuration data for a path is retrieved during a path
verification and used only temporarily. If a path is newly added to the
I/O setup after a boot, no configuration data will be stored for this
particular path.
However, this data is required for later use and should be present for
a valid I/O path anyway. Store this data during the path verification so
that newly added paths can provide all information necessary.

[sth@linux.ibm.com: fix conf_data memleak]

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Move duplicate code to separate function

For storing retrieved path information both the if and else block in
dasd_eckd_read_conf() use the same code. To avoid duplicate code this
should be done after the if/else block. To further increase readability,
move the code to a new function, dasd_eckd_store_conf_data().

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Remove unused parameter from dasd_generic_probe()

The discipline argument in dasd_generic_probe() isn't used and there is
no history how it was used in the past. Remove it.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix data corruption for thin provisioned devices

Devices are formatted in multiple of tracks.
For an Extent Space Efficient (ESE) volume we get errors when accessing
unformatted tracks. In this case the driver either formats the track on
the flight for write requests or returns zero data for read requests.

In case a request spans multiple tracks, the indication of an unformatted
track presented for the first track is incorrectly applied to all tracks
covered by the request. As a result, tracks containing data will be handled
as empty, resulting in zero data being returned on read, or overwriting
existing data with zero on write.

Fix by determining the track that gets the NRF error.
For write requests only format the track that is surely not formatted.
For Read requests all tracks before have returned valid data and should not
be touched.
All tracks after the unformatted track might be formatted or not. Those are
returned to the blocklayer to build a new request.

When using alias devices there is a chance that multiple write requests
trigger a format of the same track which might lead to data loss. Ensure
that a track is formatted only once by maintaining a list of currently
processed tracks.

Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes")
Cc: stable@vger.kernel.org # 5.3+
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: fix memleak in path handling error case

If for whatever reason the dasd_eckd_check_characteristics() function
exits after at least some paths have their configuration data
allocated those data is never freed again. In the error case the
device->private pointer is set to NULL and dasd_eckd_uncheck_device()
will exit without freeing the path data because of this NULL pointer.

Fix by calling dasd_eckd_clear_conf_data() for error cases.

Also use dasd_eckd_clear_conf_data() in dasd_eckd_uncheck_device()
to avoid code duplication.

Reported-by: Qian Cai <cai@lca.pw>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd/cio: Interpret ccw_device_get_mdc return value correctly

The max data count (mdc) is an unsigned 16-bit integer value as per AR
documentation and is received via ccw_device_get_mdc() for a specific
path mask from the CIO layer. The function itself also always returns a
positive mdc value or 0 in case mdc isn't supported or couldn't be
determined.

Though, the comment for this function describes a negative return value
to indicate failures.

As a result, the DASD device driver interprets the return value of
ccw_device_get_mdc() incorrectly. The error case is essentially a dead
code path.

To fix this behaviour, check explicitly for a return value of 0 and
change the comment for ccw_device_get_mdc() accordingly.

This fix merely enables the error code path in the DASD functions
get_fcx_max_data() and verify_fcx_max_data(). The actual functionality
stays the same and is still correct.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Revert "s390/dasd: Add discard support for ESE volumes"

This reverts commit 7e64db1597fe114b83fe17d0ba96c6aa5fca419a.

The thin provisioning feature introduces an IOCTL and the discard support
to allow userspace tools and filesystems to release unused and previously
allocated space respectively.

During some internal performance improvements and further tests, the
release of allocated space revealed some issues that may lead to data
corruption in some configurations when filesystems are mounted with
discard support enabled.

While we're working on a fix and trying to clarify the situation,
this commit reverts the discard support for ESE volumes to prevent
potential data corruption.

Cc: <stable@vger.kernel.org> # 5.3
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Fix error handling during online processing

It is possible that the CCW commands for reading volume and extent pool
information are not supported, either by the storage server (for
dedicated DASDs) or by z/VM (for virtual devices, such as MDISKs).

As a command reject will occur in such a case, the current error
handling leads to a failing online processing and thus the DASD can't be
used at all.

Since the data being read is not essential for an fully operational
DASD, the error handling can be removed. Information about the failing
command is sent to the s390dbf debug feature.

Fixes: c729696bcf8b ("s390/dasd: Recognise data for ESE volumes")
Cc: <stable@vger.kernel.org> # 5.3
Reported-by: Frank Heimes <frank.heimes@canonical.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Handle out-of-space constraint

The storage server issues three different types of out-of-space messages
whenever the Extent Pool or Extent Repository space runs short. When a
configured warning watermark is reached, the physical space is
completeley exhausted, or the capacity constraints have been relieved, a
message is received.

A log entry for the sysadmin to react to is generated in any case. In
case the physical space is completely exhausted, sense data that reads
"no space left on device" is received. In this case, currently running
I/O will be blocked until space has either been released or added to the
extent pool, and a relieve message was received via an attention
interrupt.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Add discard support for ESE volumes

ESE (Extent Space Efficient) volumes are thin-provisioned and therefore
space is only occupied with real data. In order to make previously used
space available for re-allocation again, discard support is enabled for
ESE volumes allowing the DASD driver to release said space.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Make dasd_setup_queue() a discipline function

ECKD, FBA, and the DIAG discipline use slightly different block layer
settings. In preparation of even more diverse queue settings, make
dasd_setup_queue() a discipline function.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Add new ioctl to release space

Userspace tools might have the need to release space for Extent Space
Efficient (ESE) volumes when working with such a device.

Provide the necessarry interface for such a task by implementing a new
ioctl BIODASDRAS. The ioctl uses the format_data_t data structure for
data input:

typedef struct format_data_t {
unsigned int start_unit; /* from track */
unsigned int stop_unit; /* to track */
unsigned int blksize; /* sectorsize */
unsigned int intensity;
} format_data_t;

If the intensity is set to 0x40, start_unit and stop_unit are ignored
and space for the entire volume is released. Otherwise, if intensity is
set to 0, the respective range is released (if possible).

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Add dynamic formatting support for ESE volumes

A dynamic formatting is issued whenever a write request returns with
either a No Record Found error (Command Mode), Incorrect Length error
(Transport Mode), or File Protected error (Transport Mode). All three
cases mean that the tracks in question haven't been initialized in a
desired format yet.

The part of the volume that was tried to be written on is then formatted
and the original request is re-queued.

As the formatting will happen during normal I/O operations, it is quite
likely that there won't be any memory available to build the respective
request. Another two pages of memory are allocated per volume
specifically for the dynamic formatting.

The dasd_eckd_build_format() function is extended to make sure that the
original startdev is reused. Also, all formatting and format check
functions use the new memory pool exclusively now to reduce complexity.

Read operations will always return zero data when unformatted areas are
read.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Recognise data for ESE volumes

In order to work with Extent Space Efficient (ESE) volumes, certain
viable information about those volumes and the corresponding extent
pool (such as extent size, configured space, allocated space, etc.) can
be provided.

Use the CCW commands Volume Storage Query and Logical Configuration
Query to receive detailed information about ESE volumes and the extent
pool respectively. These information are made accessible via internal
functions for subsequent users, and via sysfs attributes for userpsace
usage.

The new sysfs attributes reside in separate directories called capacity
and extent_pool.

attributes:
ese:
0/1 depending on whether the volume is an ESE volume

Capacity related attributes:
space_allocated:
Space currently allocated by the volume (in cyl)
space_configured:
Remaining space in the extent pool (in cyl)
logical_capacity:
The entire addressable space for this volume (in cyl)

Extent Pool related attributes:
pool_id:
ID of the extent pool the volume in question resides in
pool_oos:
Extent pool is out-of-space
extent_size:
Size of a single extent in this pool
cap_at_warnlevel
Extent pool capacity at warn level
warn_threshold:
Threshold at which percentage of remaining extent pool space a
warning message is issued

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Make layout analysis ESE compatible

The disk layout and volume information of a DASD reside in the first two
tracks of cylinder 0. When a DASD is set online, currently the first
three tracks are read and analysed to confirm an expected layout.

For CDL (Compatible Disk Layout) only count area data of the first track
is evaluated and checked against expected key and data lengths. For LDL
(Linux Disk Layout) the first and third track is evaluated. However,
an LDL formatted volume is expected to be in the same format across all
tracks. Checking the third track therefore doesn't have any more value
than checking any other track at random.

Now, an Extent Space Efficient (ESE) DASD is initialised by only
formatting the first two tracks, as those tracks always contain all
information necessarry.

Checking the third track on an ESE volume will therefore most likely
fail with a record not found error, as the third track will be empty.
This in turn leads to the device being recognised with a volume size of
0. Attempts to write volume information on the first two tracks then
fail with "no space left on device" errors.

Initialising the first three tracks for an ESE volume is not a viable
solution, because the third track is already a regular track and could
contain user data. With that there is potential for data corruption.

Instead, always only analyse the first two tracks, as it is sufficiant
for both CDL and LDL, and allow ESE volumes to be recognised as well.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: Remove old defines and function

Commit 4d284cac76d0 ("[S390] Avoid excessive inlining.") removed
bytes_per_record() which was the only user of the defines ECKD_C0 and
ECKD_F*, and round_up_multiple(). Let's get rid of those.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

s390/dasd: fix build warning in dasd_eckd_build_cp_raw

Commit 72deb455b5ec619f ("block: remove CONFIG_LBDAF") changes
sector_t to u64 unconditionaly, so apply '%llu' for print
sector_t variable.

Fixes: 72deb455b5ec619f ("block: remove CONFIG_LBDAF")
Cc: linux-s390@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

s390/dasd: Fix capacity calculation for large volumes

The DASD driver incorrectly limits the maximum number of blocks of ECKD
DASD volumes to 32 bit numbers. Volumes with a capacity greater than
2^32-1 blocks are incorrectly recognized as smaller volumes.

This results in the following volume capacity limits depending on the
formatted block size:

BLKSIZE MAX_GB MAX_CYL
512 2047 5843492
1024 4095 8676701
2048 8191 13634816
4096 16383 23860929

The same problem occurs when a volume with more than 17895697 cylinders
is accessed in raw-track-access mode.

Fix this problem by adding an explicit type cast when calculating the
maximum number of blocks.

Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix using offset into zero size array error

Dan Carpenter reported the following:

The patch 52898025cf7d: "[S390] dasd: security and PSF update patch
for EMC CKD ioctl" from Mar 8, 2010, leads to the following static
checker warning:

drivers/s390/block/dasd_eckd.c:4486 dasd_symm_io()
error: using offset into zero size array 'psf_data[]'

drivers/s390/block/dasd_eckd.c
4458 /* Copy parms from caller */
4459 rc = -EFAULT;
4460 if (copy_from_user(&usrparm, argp, sizeof(usrparm)))
^^^^^^^
The user can specify any "usrparm.psf_data_len". They choose zero by
mistake.

4461 goto out;
4462 if (is_compat_task()) {
4463 /* Make sure pointers are sane even on 31 bit. */
4464 rc = -EINVAL;
4465 if ((usrparm.psf_data >> 32) != 0)
4466 goto out;
4467 if ((usrparm.rssd_result >> 32) != 0)
4468 goto out;
4469 usrparm.psf_data &= 0x7fffffffULL;
4470 usrparm.rssd_result &= 0x7fffffffULL;
4471 }
4472 /* alloc I/O data area */
4473 psf_data = kzalloc(usrparm.psf_data_len, GFP_KERNEL
| GFP_DMA);
4474 rssd_result = kzalloc(usrparm.rssd_result_len, GFP_KERNEL
| GFP_DMA);
4475 if (!psf_data || !rssd_result) {

kzalloc() returns a ZERO_SIZE_PTR (0x16).

4476 rc = -ENOMEM;
4477 goto out_free;
4478 }
4479
4480 /* get syscall header from user space */
4481 rc = -EFAULT;
4482 if (copy_from_user(psf_data,
4483 (void __user *)(unsigned long)
usrparm.psf_data,
4484 usrparm.psf_data_len))

That all works great.

4485 goto out_free;
4486 psf0 = psf_data[0];
4487 psf1 = psf_data[1];

But now we're assuming that "->psf_data_len" was at least 2 bytes.

Fix this by checking the user specified length psf_data_len.

Fixes: 52898025cf7d ("[S390] dasd: security and PSF update patch for EMC CKD ioctl")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix hanging offline processing due to canceled worker

During offline processing two worker threads are canceled without
freeing the device reference which leads to a hanging offline process.

Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix panic for failed online processing

Fix a panic that occurs for a device that got an error in
dasd_eckd_check_characteristics() during online processing.
For example the read configuration data command may have failed.

If this error occurs the device is not being set online and the earlier
invoked steps during online processing are rolled back. Therefore
dasd_eckd_uncheck_device() is called which needs a valid private
structure. But this pointer is not valid if
dasd_eckd_check_characteristics() has failed.

Check for a valid device->private pointer to prevent a panic.

Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: replace PTR_RET with PTR_ERR_OR_ZERO

PTR_RET is deprecated, use PTR_ERR_OR_ZERO instead.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: move dasd_ccw_req to per request data

Let the block layer allocate per request data to store
struct dasd_ccw_req. We still need extra preallocated
memory for usage by ccw programs (which vary in length)
and for requests which don't originate from the block
layer.

Link: https://lkml.kernel.org/r/20180530074130.GA6927@infradead.org
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: rename struct channel_path_desc

Rename struct channel_path_desc to struct channel_path_desc_fmt0
to fit the scheme. Provide a macro for the function wrappers that
gather this and related data from firmware.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: set timestamps unconditionally

Set the XRC timestamps even if XRC is not supported by the storage server
to help debugging the storage server firmware.
Do not advertise valid time stamps if the system time could not be
obtained.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Simplify code

Use 'seq_printf(m, "...%*phN...")' instead of duplicating its
implementation.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: prevent prefix I/O error

Prevent that a prefix flag is set based on invalid configuration data.
The validity.verify_base flag should only be set for alias devices.
Usually the unit address type is either one of base, PAV alias or
HyperPAV alias. But in cases where the unit address type is not set or
any other value the validity.verify_base flag might be set as well.
This would lead to follow on errors.
Explicitly check for alias devices and set the validity flag only for
them.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: block: add SPDX identifiers to the remaining files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/s390/block/ files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Stefan Haberland <sth@linux.vnet.ibm.com>
Cc: Jan Hoeppner <hoeppner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Change unsigned long long to unsigned long

Unsigned long long and unsigned long were different in size for 31-bit.
For 64-bit the size for both datatypes is 8 Bytes and since the support
for 31-bit is long gone we can clean up a little and change everything
to unsigned long.
Change get_phys_clock() along the way to accept unsigned long as well so
that the DASD code can be consistent.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Make raw I/O usable without prefix support

The Prefix CCW is not mandatory and raw I/O can also be issued without
it. Check whether the Prefix CCW is supported and if not use the
combination of Define Extent and Locate Record Extended instead.

While at it, sort the variable declarations, replace the gotos with
early exits, and remove an error check at the end which is irrelevant.
Also, remove the XRC check as it is not relevant for raw I/O.

Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Rename dasd_raw_build_cp()

Rename dasd_raw_build_cp() to dasd_eckd_build_cp_raw() to fit the
scheme.

Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Refactor prefix_LRE() and related functions

We already have define_extent() that prepares necessary data for the
Define Extent CCW. The exact same thing is done in prefix_LRE().

Remove the duplicate code and move commands that were only used in
combination with the Prefix command to define_extent(). One of these
commands needs the blocksize to be specified. Add the blksize parameter
to define_extent() to account for that.

In addition, the check_XRC() function can be made more generic. Do this
and remove the Prefix-specific check_XRC_on_prefix() function.

Furthermore, prefix_LRE() uses fill_LRE_data() to prepare Locate Record
Extended data. Rename the function to fit the scheme better and make it
usable outside of the Prefix context by adding the corresponding CCW
command.

Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: suppress command reject error for query host access command

On some z/VM systems the query host access command is not supported for
temp disks, though the corresponding feature code is set.
This does not have any impact beside that the information is not available.
Suppress the full blown command reject error messages to not confuse the
user. The error is still logged in the s390dbf.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: check if query host access feature is supported

Some storage servers might not support the query host access feature.
Check if the corresponding feature code is set.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix spelling mistake: "supportet" -> "supported"

trivial fix to spelling mistake in literal string

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: correct inconsistent indenting

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

s390/dasd: channel path aware error recovery

With this feature, the DASD device driver more robustly handles DASDs
that are attached via multiple channel paths and are subject to
constant Interface-Control-Checks (IFCCs) and Channel-Control-Checks
(CCCs) or loss of High-Performance-FICON (HPF) functionality on one or
more of these paths.

If a channel path does not work correctly, it is removed from normal
operation as long as other channel paths are available. All extended
error recovery states can be queried and reset via user space
interfaces.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: extend dasd path handling

Store flags and path_data per channel path.
Implement get/set functions for various path masks.
The patch does not add functional changes.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: avoid undefined behaviour

the mdc value can be quite big (like 65535), so we are in undefined
territory when doing the multiplication with the (also signed)
FCX_MAX_DATA_FACTOR as outlined by UBSAN:

UBSAN: Undefined behaviour in drivers/s390/block/dasd_eckd.c:1678:14
signed integer overflow:
65535 * 65536 cannot be represented in type 'int'
CPU: 5 PID: 183 Comm: kworker/u512:1 Not tainted 4.7.0+ #150
Workqueue: events_unbound async_run_entry_fn
000000fb8b59f900 000000fb8b59f990 0000000000000002 0000000000000000
000000fb8b59fa30 000000fb8b59f9a8 000000fb8b59f9a8 000000000011732e
00000000000000a4 0000000000a309e2 0000000000a4c072 000000000000000b
000000fb8b59f9f0 000000fb8b59f990 0000000000000000 0000000000000000
0400000000d83238 000000000011732e 000000fb8b59f990 000000fb8b59f9f0
Call Trace:
([<0000000000117260>] show_trace+0x98/0xa8)
([<00000000001172e0>] show_stack+0x70/0xf0)
([<000000000053ac96>] dump_stack+0x86/0xb8)
([<000000000057f5f8>] ubsan_epilogue+0x28/0x70)
([<000000000057fe9e>] handle_overflow+0xde/0xf0)
([<00000000006c322a>] dasd_eckd_check_characteristics+0x50a/0x550)
([<00000000006b42ca>] dasd_generic_set_online+0xba/0x380)
([<0000000000693d82>] ccw_device_set_online+0x192/0x550)
([<00000000006ac1ae>] dasd_generic_auto_online+0x2e/0x70)
([<0000000000172130>] async_run_entry_fn+0x70/0x270)
([<0000000000165a72>] process_one_work+0x26a/0x638)
([<0000000000165e8a>] worker_thread+0x4a/0x658)
([<000000000016dd9c>] kthread+0x10c/0x110)
([<00000000008963ae>] kernel_thread_starter+0x6/0xc)
([<00000000008963a8>] kernel_thread_starter+0x0/0xc)

As this is a runtime value there is actually no risk of any sane
compiler to detect and (ab)use this undefinedness, but let's make
the multiplication defined by making mdc unsigned.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: make query host access interruptible

If the DASD device gets blocked for any reason, e.g. because it is reserved
somewhere, the host_access_count sysfs entry or the host_access_list
debugfs entry may sleep forever. Make it interruptible so that userspace
can use ^C to abort the operation.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix failing CUIR assignment under LPAR

On LPAR the read message buffer command should be executed on the path
it was received on otherwise there is a chance that the CUIR assignment
might be faulty and the wrong channel path is set online/offline.

Fix by setting the path mask accordingly.
On z/VM we might not be able to do I/O on this path but there it does
not matter on which path the read message buffer command is executed.
Therefor implement a retry with an open path mask.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>

s390/time: LPAR offset handling

It is possible to specify a user offset for the TOD clock, e.g. +2 hours.
The TOD clock will carry this offset even if the clock is synchronized
with STP. This makes the time stamps acquired with get_sync_clock()
useless as another LPAR migth use a different TOD offset.

Use the PTFF instrution to get the TOD epoch difference and subtract
it from the TOD clock value to get a physical timestamp. As the epoch
difference contains the sync check delta as well the LPAR offset value
to the physical clock needs to be refreshed after each clock
synchronization.

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

s390/dasd: Add new ioctl BIODASDCHECKFMT

Implement new DASD IOCTL BIODASDCHECKFMT to check a range of tracks on a
DASD volume for correct formatting. The following characteristics are
checked:
- Block size
- ECKD key length
- ECKD record ID
- Number of records per track

Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: add query host access to volume support

With this feature, applications can query if a DASD volume is online
to another operating system instances by checking the online status of
all attached hosts from the storage server.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: reorder lcu and device lock

Reorder lcu and device lock to get rid of the error-prone trylock
mechanism.

The locking order is lcu lock -> device lock.
This protects against changes to the lcu device lists and enables us
to iterate over the devices, take the cdev lock and make changes to
the device structures.

The complicated part is the summary unit check handler that gets an
interrupt on one device of the lcu that leads to structural changes of
the whole lcu itself. This work needs to be done even if devices on
the lcu disappear. So a device independent worker is used.
The old approach tried to update some lcu structures and set up the
lcu worker in the interrupt context with the device lock held.
But this forced the lock order "cdev lock -> lcu lock" that made it
hard to have the lcu lock held and iterate over all devices and change
them.

The new approach is to schedule a device specific worker that gets
out of the interrupt context and rid of the device lock for summary
unit checks. This worker is able to take the lcu lock and schedule the
lcu worker that updates all devices. The time between interrupt and
worker execution is no problem because the devices in the lcu reject
all I/O in this time with an appropriate error. The dasd driver can
deal with this situation and re-drive the I/O later on.

Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: remove casts to dasd_*_private

Convert dasd_device.private to be a void pointer to get
rid of a lot of explicit casts.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Refactor dasd format functions

Prepare for new format checking function by renaming functions and
moving reusable code to separate functions:

- Move sanity checks into a new function and make it reusable.
- Move common format code to a new function called
dasd_eckd_format_process_data.
- Create the generic function dasd_eckd_format_build_ccw_req, which
itself will then decide what ccw request is being built according to
the input data. (with upcoming functionality).

Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: Improve dasd format code

- Make sure a calling function can rely on data in fdata by resetting to
its initial values
- Move special treatment for track 0 and 1 to dasd_eckd_build_format
- Replace dangerous backward goto with a loop logic
- Add define for number that specifies the maximum amount of CCWs per
request and is used for format_step calculation
- Remove unused variable

Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix disconnected device with valid path mask

Path verification is either done via dasd_eckd_read_conf() which is
triggered during online processing and resume or via
do_path_verification_work() which is triggered after path events.
The dasd_eckd_read_conf() version added paths unconditionally and did
not check if the path mask was empty. This led to devices having the
disconnected stop flag set but a valid path mask. So they where not
working although they had paths validated successfully. After a resume
this state could even not be solved with additional paths added.

Fix by checking for an empty path mask in dasd_eckd_read_conf() and
clearing the device stop bits for a newly added channel path.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix invalid PAV assignment after suspend/resume

For a valid PAV assignment the DASD driver needs to notice possibly
changed configuration data. Thus the failing of read configuration
data should also fail the device restore to prevent invalid PAV
assignment. The failed device may get restored after additional paths
get available later on.
If the restore fails after the device was added to the lcu alias
handling it needs to be removed from the alias handling before exiting
the restore function.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix double free in dasd_eckd_read_conf

The configuration data is stored per path and also the first valid
configuration data per device. When dasd_eckd_read_conf is called
again after a path got lost the device configuration data is cleared
but possibly not the per path configuration data. This might lead to a
double free when the lost path gets operational again.

Fix by clearing all per path configuration data when the first valid
configuration data is received and stored.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/cio: introduce pathmask_to_pos

We often need to correlate an 8 bit path mask with the position
in a channel path array. Introduce and use pathmask_to_pos for
that task.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390: remove unneeded sizeof(void *) comparisons

Remove two more statements which always evaluate to 'false'.
These are more leftovers from the 31 bit era.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: enhance CUIR scope detection

This patch adds an enhanced detection for control unit initiated
reconfiguration request scope.
The first approach assumed the scope of the reconfiguration request
to be restricted to the path on which the message was received.
The enhanced approach determines the full scope of the reconfiguration
request by evaluating additional path and device selection information
contained in the reconfiguration message.

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix failing path verification

DASD path verification requires the usage of sleep_on_immediatly to
ensure that no other I/O request is blocking the recovery of
disconnected devices. But two concurrent path verification workers for
the same device may kill each others requests due to the usage of the
immediate sleep_on function. This may lead to unsuccessful path
verifications.

Prevent that two parallel path verification workers conflict with
each other by implementing a device flag signalling a already running
worker.

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

s390/dasd: fix inability to set a DASD device offline

Fix ref counting for DASD devices leading to an inability to set a
DASD device offline.
Before a worker is scheduled the DASD device driver takes a reference
to the device. If the worker was already scheduled this reference was
never freed.
Fix by giving the reference to the DASD device free when
schedule_work() returns false.

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

s390: remove 31 bit support

Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.

The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.

Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.

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

s390/dasd: add support for control unit initiated reconfiguration

Add support for Control Unit Initiated Reconfiguration (CUIR) to
Linux, a storage server interface to reconcile concurrent hardware
changes between storage and host.

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

s390/dasd: fix camel case

Rename enable_PAV to enable_pav.

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

dasd: fix error recovery for alias devices during format

Kernel panic or a hanging device during format if an alias device is
set offline or I/O errors occur.

Omit the error recovery procedure for alias devices and do retries on
the base device with full erp.

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

dasd: use aliases for formatted devices during format

Formatting of a previously formatted device is slower than newly
format a device when alias devices are available.
For already formatted devices the alias devices are not used for
formatting.

Fix the alias handling for already formatted devices.

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

block: Convert bio_for_each_segment() to bvec_iter

More prep work for immutable biovecs - with immutable bvecs drivers
won't be able to use the biovec directly, they'll need to use helpers
that take into account bio->bi_iter.bi_bvec_done.

This updates callers for the new usage without changing the
implementation yet.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: Jim Paris <jim@jtan.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: support@lsi.com
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
Cc: cbe-oss-dev@lists.ozlabs.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: DL-MPTFusionLinux@lsi.com
Cc: linux-scsi@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-fsdevel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: linux-mm@kvack.org
Acked-by: Geoff Levand <geoff@infradead.org>

s390/dasd: validate request size before building CCW/TCW request

An I/O request that does not read or write full blocks cannot be
translated into a correct CCW or TCW program and should be rejected
right away. In particular the code that creates TCW requests will not
notice this problem and create broken TCWs that will be rejected by
the hardware.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Reference-ID: RQM1956

s390/dasd: check for availability of prefix command during format

The prefix command is used instead of a define extent to make use of
PAV alias devices during format. On some older storage servers the
prefix command may not be available and the IO request will fail.
Check for availability of prefix command and use define extent if
not available.

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

s390/dasd: enable raw_track_access reads without direct I/O

The ECKD protocol supports reading of tracks with arbitrary format as
raw track images. The DASD device driver supports this in its
raw_track_access mode. In this mode it maps each track to sixteen 4096
byte sectors and rejects all requests that are not properly aligned to
this mapping.

An application that wants to use a DASD in raw_track_access mode will
usually use direct I/O to make sure that properly aligned requests are
directly submitted to the driver. However, applications that are not
aware of this mode, e.g. udev, will encounter I/O errors.

To make the use without direct I/O possible and avoid this kind of
alignment errors, we now pad unaligned read requests with a dummy
page, so that we can always read full tracks. Please note that
writing is still only possible for full track images that are properly
aligned.

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

s390/dasd: Implement block timeout handling

This patch implements generic block layer timeout handling
callbacks for DASDs. When the timeout expires the respective
cqr is aborted.

With this timeout handler time-critical request abort
is guaranteed as the abort does not depend on the internal
state of the various DASD driver queues.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Acked-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: make number of retries configurable

Instead of having the number of retries hard-coded in the various
functions we should be using a default retry value, which can
be modified via sysfs.

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

s390/dasd: Cocci spatch "ptr_ret.spatch"

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: improve speed of dasdfmt

Reorganize format IO requests and enable usage of PAV.

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

s390/dasd: fix unresponsive device after all channel paths were lost

Failfast bit was set incorrectly.
Use set_bit to enable failfast.

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

s390/time: rename tod clock access functions

Fix name clash with some common code device drivers and add "tod"
to all tod clock access function names.

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

s390/irq: remove split irq fields from /proc/stat

Now that irq sum accounting for /proc/stat's "intr" line works again we
have the oddity that the sum field (first field) contains only the sum
of the second (external irqs) and third field (I/O interrupts).
The reason for that is that these two fields are already sums of all other
fields. So if we would sum up everything we would count every interrupt
twice.
This is broken since the split interrupt accounting was merged two years
ago: 052ff461c8427629aee887ccc27478fc7373237c "[S390] irq: have detailed
statistics for interrupt types".
To fix this remove the split interrupt fields from /proc/stat's "intr"
line again and only have them in /proc/interrupts.

This restores the old behaviour, seems to be the only sane fix and mimics
a behaviour from other architectures where /proc/interrupts also contains
more than /proc/stat's "intr" line does.

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

s390/dasd: fix unaccessible device after resume

If a channel path is cabled incorrectly and the device is suspended and
resumed the device may be inaccessible afterwards.
Make the path connection check not interrupt the resume callback there
could be other valid paths available.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Reference-ID: RQM 1262
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

s390/dasd: fix multi-line printks with multiple KERN_<level>s

Do not use more than one KERN_<level> per printk.

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

s390/dasd: check count address during online setting

A common way to prepare a z/VM mini disk is to format the real device
with a z/VM tool like CPFMTXA and then define a mini disk that excludes
the first cylinder, i.e. the cylinder 0 of the virtual disk is located
at cylinder 1 of the real device.

The DASD device driver will recognize such a mini disk as formatted, as
the uniform record layout on the disk matches that of an LDL formatted
device. However, the cylinder value in the 'count' field of the ECKD
records matches the geometry of the real device, and not that of the
mini disk, so I/O requests will fail with 'record not found' errors.

To make the mini disk usable, it needs to be formatted with a tool like
dasdfmt. To enable tools like distribution installation tools to
recognize this situation, the DASD device driver should report such a
mini disk as 'not formatted'.
To this end we need to extend the device recognition code to check not
just for proper record sizes, but also for proper cylinder/head/record
values.

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>

s390/etr,stp: use -EOPNOTSUPP instead of -ENOSYS

Change -ENOSYS to -EOPNOTSUPP. Return value is used only internally.

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

s390: add eadm facility bits

Add the eadm facility bits to the css characteristics and move
them to a new header.

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

s390/dasd: fix pathgroup race

If a new path is available we need to verify the path data. If it is the
first path for a device the stop bits are removed after path verification.
If a pathgroup is established we need to set system characteristics for
the lcu. Therefore I/O has to be started.
If the device is stopped the set system characteristics worker may block
the path verification worker and the device is blocked.

Turn on failfast for set system characteristics CQR to prevent a deadlock
with the path verification worker.

If a pathgroup is established on a device that is not in use trigger path
verification. Maybe we were not informed about a working path.

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>

s390/dasd: fix ioctl return value

For unimplemented ioctls the dasd driver should return -ENOTTY.

Reported-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Acked-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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>

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>

[S390] drivers/s390/block/dasd_eckd.c: add missing dasd_sfree_request

Extend some error paths to call dasd_sfree_request as done earlier in the
function. The error-handling code is also moved to the end of the function.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[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>

compat: fix compile breakage on s390

The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.

This is the minimal patch which fixes the build issues.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[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>

[S390] dasd: revert LCU optimization

Remove the optimization that validate server is only called once per
LCU. If a device is set online we only know that we already know the
LCU. But if the pathgroup was lost in between we have to do a
validate server again to activate some features.
Since we have no indication when a pathgroup gets lost we have to do
a validate server every time a device is set online.

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

[S390] dasd: fix fixpoint divide exception in define_extent

If an IO request is build on an alias device without prefix enabled
we try to calculate with zero data from the alias device. This
triggers a BUG statement with fixpoint divide exception.
This case is very unlikely and can only happen if the pathgroup is
lost with an alias device already in use.
Prevent the alias device from being used in this case.

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

[S390] dasd: add sanity check to detect path connection error

Prevents possible data corruption by detecting cabling error.
Therefor read and compare the UID for all available channel paths.

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

[S390] sparse: fix sparse NULL pointer warnings

Fix two NULL pointer warnings in the dasd driver:

drivers/s390/block/dasd_eckd.c:2353:20: warning: Using plain integer as NULL pointer
drivers/s390/block/dasd_eckd.c:2415:44: warning: Using plain integer as NULL pointer

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

[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>

[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>

[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>

[S390] dasd: check if raw track access is supported

To use raw track access some special storage server commands are
needed. Older storage hardware may not support these commands.
So check if raw track access is possible while setting the DASD
online.

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>

[S390] dasd: fix return code handling

Check return value of itcw_add_dcw() for error code and return it.

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

[S390] get rid of unused variables

Remove trivially unused variables as detected with -Wunused-but-set-variable.

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

[S390] dasd: check sense type in device change handler

When evaluating sense data in dasd_eckd_check_for_device_change, we
must always check for the type of sense data in byte 27, bit 0, to
make sure that the rest of the sense data is interpreted correctly.

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

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

[S390] ccw_driver: remove duplicate members

Remove the owner and name members of struct
ccw_driver and convert all drivers to store
this data in the embedded struct device_driver.

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

[S390] dasd: get rid of compile warning

Get rid of this:

drivers/s390/block/dasd_eckd.c: In function 'dasd_eckd_build_cp_tpm_track.clone.8':
drivers/s390/block/dasd_eckd.c:2589:34: warning: 'len_to_track_end' may be used uninitialized in this function

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

[S390] dasd: correct device table

The 3880 storage control unit supports a 3380 device
type, but not a 3390 device type.

Reported-by: Stephen Powell <zlinuxman@wowway.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[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>

[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>

[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>

[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>

[S390] dasd: provide a Sense Path Group ID ioctl

The BIODASDSNID ioctl executes a 'Sense Path Group ID'
command on a DASD ECKD device. The returned path group data
allows user space programs to determine path state and
path group ID of the channel paths to the device.

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

[S390] dasd: fix unsolicited interrupt recognition

The dasd interrupt handler needs to distinguish solicited from
unsolicited interrupts, as unsolicited interrupts may require special
handling (e.g. summary unit checks) and solicited interrupts require
proper error recovery for the failed I/O request.
The interrupt handler needs to check several bit fields in the
interrupt response block (irb) to make this distinction.
So far our check of the status control bits has not been specific
enough, which may lead to a failed request getting just retried
instead of the necessary error recovery.

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

[S390] dasd fix dump_sense_dbf

The dasd_eckd_dump_sense_dbf function uses a macro for s390 debug
feature that can handle up to 8 parameters (for the DASD device
driver).
Fix the function to use only the maximum number of parameters.

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

Fix various typos of valid in comments

Fix various typos of valid.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

[S390] dasd: tunable missing interrupt handler

This feature provides a user interface to specify the timeout for
missing interrupts for standard I/O operations.

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

[S390] dasd: allocate fallback cqr for reserve/release

The DASD reserve and release ioctls use the preallocated memory pool
of the respective device to build their CCW requests. However, when
the device is busy, the pool may already be empty and the ioctl fails.
Usually this can be recovered by calling the ioctl again, but in
a situation in which we need to issue an unconditional reserve to
make a device operational again, this would be not recoverable.
To avoid a failure due to lack of memory, DASD device driver will
preallocate enough memory for a single reserve/release request, which
can be used if normal allocation fails.

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

[S390] dasd: unit check handling during internal cio I/O

React on unit checks during cio internal I/O.
Handle as unsolicited interrupt and advice cio to retry.

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

[S390] dasd: remove uid from devmap

Remove the duplicate of the DASD uid from the devmap structure.
Use the uid from the device private structure instead.
This also removes a lockdep warning complaining about a possible
SOFTIRQ-safe -> SOFTIRQ-unsafe lock order.

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

[S390] dasd: add dynamic pav toleration

For base Parallel Access Volume (PAV) there is a fixed mapping of
base and alias devices. With dynamic PAV this mapping can be changed
so that an alias device is used with another base device.
This patch enables the DASD device driver to tolerate dynamic PAV
changes.

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

[S390] dasd: check tsb validity

Check tsb validity before the tcw_get_tsb function is called.

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

[S390] dasd: automatic recognition of read-only devices

In z/VM it is possible to attach a device as read-only. To prevent
unintentional write requests and subsequent I/O errors, we can detect
this configuration using the z/VM DIAG 210 interface and set the
respective linux block device to read-only as well.

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

[S390] dasd: security and PSF update patch for EMC CKD ioctl

Remove the PSF order/suborder check from the Symmetrix CKD dasd ioctl.
In exchange restrict the ioctl to CAP_SYS_ADMIN and CAP_SYS_RAWIO.

Signed-off-by: Nigel Hislop <hislop_nigel@emc.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd: fix possible NULL pointer errors

Fix possible NULL pointer in DASD messages and correct discipline
checking.

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

[S390] dasd: add proper compat pointer conversion for symmetrix ioctl

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

[S390] dasd: let device initialization wait for LCU setup

The first DASD that is set online for a specific logical control unit
has to do certain setup steps on the storage server to make full use
of it, for example it will enable PAV.
The features and characteristics reported by the storage server will
depend on this setup, so all other devices on the same LCU will need
to wait for the setup to be finished.

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

[S390] dasd: remove strings from s390dbf

Remove strings from s390 debugfeature entries that could lead to a
crash when the data is read from dbf because the strings do not exist
any more.

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

[S390] dasd: improve error recovery for internal I/O

Most of the error conditions reported by a FICON storage server
indicate situations which can be recovered. Sometimes the host just
needs to retry an I/O request, but sometimes the recovery
is more complex and requires the device driver to wait, choose
a different path, etc.

The DASD device driver has a fully featured error recovery
for normal block layer I/O, but not for internal I/O request which
are for example used during the device bring up.
This can lead to situations where the IPL of a system fails because
DASD devices are not properly recognized.
This patch will extend the internal I/O handling to use the existing
error recovery procedures.

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

[S390] dasd: enable prefix independent of pav support

The DASD device driver needs to explicitly enable the prefix command
on the storage server, before it can be used. Originally we enabled
this command along with others only if we wanted to support PAV.
However, today we require this command for other features like
High Performance FICON as well, so we need to always enable prefix.

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

[S390] dasd: remove dead code

the todclk.h header file is dead code. Remove it.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] cio: split PGID settings and status

Split setting (driver wants feature enabled) and status (feature
setup was successful) for PGID related ccw device features so that
setup errors can be detected. Previously, incorrectly handled setup
errors could in rare cases lead to erratic I/O behavior and
permanently unusuable devices.

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

[S390] dasd: fix locking bug

Replace spin_lock with spin_lock_irqsave in dasd_eckd_restore_device.

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

[S390] dasd: fix race condition in resume code

There is a race while re-reading the device characteristics. After
cleaning the memory area a cqr is build which reads the device
characteristics. This may take a rather long time and the device
characteristics structure is zero during this. Now it could be
possible that the block tasklet starts working and a new cqr will be
build. The build_cp command refers to the device characteristics
structure and this may lead into a divide by zero exception.
Fix this by re-reading the device characteristics into a temporary
structur and copy the data to the original structure. Also take the
ccwdev_lock.

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

[S390] dasd: tolerate devices that have no feature codes

The DASD device driver reads the feature codes of a device during
device initialization. These codes are later used to determine the
availability of advanced features like PAV or High Performance FICON.
Some very old devices do not support the command to read feature
codes and the initialization routine fails.
As the feature codes are not necessary for basic DASD operations, we
can support such devices by just ignoring missing feature codes.

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

trivial: remove unnecessary semicolons

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

[S390] dasd: fix message naming

This patch fixes message naming so that generic dasd messages do not
contain the device discipline. For this purpose the dev_ makros are
replaced by pr_ makros for generic dasd messages.

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

[S390] dasd: optimize cpu usage in goodcase

remove unnecessary dbf call, remove string operations for magic

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

[S390] dasd: correct debugfeature sense dump

remove loop, add some debug data and use get_sense function

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

[S390] dasd_pm: fix stop flag handling

The stop flags are handled in the generic restore function so the
stop flag is removed also for FBA and DIAG devices.

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

[S390] pm: dasd power management callbacks.

Introduce the power management callbacks to the dasd driver. On suspend
the dasd devices are stopped and removed from the focus of alias
management.
On resume they are reinitialized by rereading the device characteristics
and adding the device to the alias management.
In case the device has gone away during suspend it will caught in the
suspend state with stopped flag set to UNRESUMED. After it appears again
the restore function is called again.

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

[S390] dasd: forward internal errors to dasd_sleep_on caller

If a DASD requests is started with dasd_sleep_on and fails, then the
calling function may need to know the reason for the failure.
In cases of hardware errors it can inspect the sense data in the irb,
but when the reason is internal (e.g. start_IO failed) then it needs
a meaningfull return code.

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

[S390] dasd: sync after async probe

Some functions called as a late_initcall depend on completely
initialized devices. Since commit
f3445a1a656bc26b07946cc6d20de1ef07c8d116 the dasd driver uses the
new async framework and relies on the fact that synchronization is
done in prepare_namespace which is called after the late_initcalls.

Fix this by calling async_synchronize_full at the end of the related
init functions.

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

[S390] dasd: check_characteristics cleanup

Fix a broken memset (sizeof pointer vs sizeof the underlying
structure) by cleaning up the involved functions.

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

[S390] dasd: no High Performance FICON in 31-bit mode

The High Performance FICON feature is not supported in 31-bit mode,
no matter what the various flags say. So we need to check for the
CONFIG_64BIT option as well.

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

block: convert to pos and nr_sectors accessors

With recent cleanups, there is no place where low level driver
directly manipulates request fields. This means that the 'hard'
request fields always equal the !hard fields. Convert all
rq->sectors, nr_sectors and current_nr_sectors references to
accessors.

While at it, drop superflous blk_rq_pos() < 0 test in swim.c.

[ Impact: use pos and nr_sectors accessors ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Mike Miller <mike.miller@hp.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Dario Ballabio <ballabio_dario@emc.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: unsik Kim <donari75@gmail.com>
Cc: Laurent Vivier <Laurent@lvivier.info>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

[S390] dasd: fix idaw boundary checking for track based ccw

A ccw command that reads or writes several records at once will
usually transfer more data then fits into one page and needs to
address memory areas using a list of indirect data address words
(idaw). All but the first of these areas must start on a 4KB or 2KB
block boundary (depending on the idaw format).
A check for this restriction was missing and has been added with
this patch.

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

[S390] dasd: message cleanup

Moved some Messages into s390 debug feature and changed remaining
messages to use the dev_xxx and pr_xxx macros.

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

[S390] dasd: add High Performance FICON support

To support High Performance FICON, the DASD device driver has to
translate I/O requests into the new transport mode control words (TCW)
instead of the traditional (command mode) CCW requests.

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

[S390] dasd: add large volume support

The dasd device driver will now support ECKD devices with more then
65520 cylinders.
In the traditional ECKD adressing scheme each track is addressed
by a 16-bit cylinder and 16-bit head number. The new addressing
scheme makes use of the fact that the actual number of heads is
never larger then 15, so 12 bits of the head number can be redefined
to be part of the cylinder address.

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

[S390] dasd_eckd / Write format R0 is now allowed BB

Permission is now granted to the subsystem to format write R0 with:
* an ID = CCHHR, where CC = physical cylinder number,
HH = physical head number, and R = 0
* a key length of zero
* a data length of eight
* a data field containing all zeros

Signed-off-by: Jean-Baptiste Joret <joret@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd: add device attribute to disable blocking on lost paths

When the connection between host and storage server is lost, the
dasd device driver usually blocks all I/O on affected devices and
waits for them to reappear. In some setups however it would be
better if the I/O is returned as error so that device can be
recovered by some other means, eg. in a raid or multipath setup.

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

[S390] dasd: correct sense byte condition for SIM

SIM sense data are always 32 bit sense data so sense byte 27 bit 0
has not to be set.

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

[SCSI] block: separate failfast into multiple bits.

Multipath is best at handling transport errors. If it gets a device
error then there is not much the multipath layer can do. It will just
access the same device but from a different path.

This patch breaks up failfast into device, transport and driver errors.
The multipath layers (md and dm mutlipath) only ask the lower levels to
fast fail transport errors. The user of failfast, read ahead, will ask
to fast fail on all errors.

Note that blk_noretry_request will return true if any failfast bit
is set. This allows drivers that do not support the multipath failfast
bits to continue to fail on any failfast error like before. Drivers
like scsi that are able to fail fast specific errors can check
for the specific fail fast type. In the next patch I will convert
scsi.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[S390] Add ioctl support for EMC Symmetrix Subsystem Control I/O

EMC Symmetrix Subsystem Control I/O through CKD dasd requires a
specific parameter list sent to the array via a Perform Subsystem
Function CCW. The Symmetrix response is retrieved from the array
via a Read Subsystem Data CCW.

Signed-off-by: Nigel Hislop <hislop_nigel@emc.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd: fix message flood for unsolicited interrupts

In the unsolicited interupt handler fake IRBs from CIO have to be
ignored because there is nothing to do.
The function dump_sense should not be called if there is no sense
data available.

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

[S390] bus_id -> dev_name conversions

bus_id -> dev_name() conversions in s390 code.

[cornelia.huck@de.ibm.com: minor adaptions]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd: Add support for enhanced VM UID

When z/VM provides two virtual devices (minidisks) that reside on the
same real device, both will receive the configuration data from the
real device and thus get the same uid. To fix this problem, z/VM
provides an additional configuration data record that allows to
distinguish between minidisks.
z/VM APAR VM64273 needs be installed so this fix has an effect.

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

[S390] dasd: fix unsolicited SIM handling.

Add missing schedule_bh and check that there is 32 bit sense data.

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

[S390] cio: introduce fcx enabled scsw format

Extend the scsw data structure to the format required by fcx. Also
provide helper functions for easier access to fields which are present
in both the traditional as well as the modified format.

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

[S390] dasd: add sim handling.

Now the system reports system information messages (SIM) to the user.
The System Reference Code (SRC) which is reported to the user gives
the abbility to lookup the reason of the SIM online in the
documentation of the storage server.

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>

[S390] dasd: add hyper PAV support to DASD device driver, part 1

Parallel access volumes (PAV) is a storage server feature, that allows
to start multiple channel programs on the same DASD in parallel. It
defines alias devices which can be used as alternative paths to the
same disk. With the old base PAV support we only needed rudimentary
functionality in the DASD device driver. As the mapping between base
and alias devices was static, we just had to export an identifier
(uid) and could leave the combining of devices to external layers
like a device mapper multipath.
Now hyper PAV removes the requirement to dedicate alias devices to
specific base devices. Instead each alias devices can be combined with
multiple base device on a per request basis. This requires full
support by the DASD device driver as now each channel program itself
has to identify the target base device.
The changes to the dasd device driver and the ECKD discipline are:
- Separate subchannel device representation (dasd_device) from block
device representation (dasd_block). Only base devices are block
devices.
- Gather information about base and alias devices and possible
combinations.
- For each request decide which dasd_device should be used (base or
alias) and build specific channel program.
- Support summary unit checks, which allow the storage server to
upgrade / downgrade between base and hyper PAV at runtime (support
is mandatory).

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

[S390] drivers/s390/: Spelling fixes

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Fixup rq_for_each_segment() indentation

Remove one level of nesting where appropriate.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

Introduce rq_for_each_segment replacing rq_for_each_bio

Every usage of rq_for_each_bio wraps a usage of
bio_for_each_segment, so these can be combined into
rq_for_each_segment.

We define "struct req_iterator" to hold the 'bio' and 'index' that
are needed for the double iteration.

Signed-off-by: Neil Brown <neilb@suse.de>

Various compile fixes by me...

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

Typo fixes errror -> error

Typo fixes errror -> error

Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[S390] Avoid sparse warnings.

Monthly sparse warning avoidance patch. Sigh.

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

[S390] dasd: New read device characteristics and read configuration data.

Instead of the deprecated read_dev_chars() and read_conf_data_lpm(),
implement dasd_generic_read_dev_chars() and dasd_eckd_read_conf_lpm().
These should even recover better from error than the original cio
functions.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] Avoid excessive inlining.

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

[S390] ETR support.

This patch adds support for clock synchronization to an external time
reference (ETR). The external time reference sends an oscillator
signal and a synchronization signal every 2^20 microseconds to keep
the TOD clocks of all connected servers in sync. For availability
two ETR units can be connected to a machine. If the clock deviates
for more than the sync-check tolerance all cpus get a machine check
that indicates that the clock is out of sync. For the lovely details
how to get the clock back in sync see the code below.

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

[S390] dasd: fix unconditional reserve handling.

The reserve/release IOCTLs sometimes do not work. If second system
does a 'steal lock' the pending unit check (Format 3 Msg F) is
delivered. Since ERP is disabled for reserve/release, the IOCTL call
fails. We have to allow basic ERP (retries) for reserve/release IOCTLs.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] Get rid of a lot of sparse warnings.

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

[PATCH] slab: remove SLAB_DMA

SLAB_DMA is an alias of GFP_DMA. This is the last one so we
remove the leftover comment too.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] Split struct request ->flags into two parts

Right now ->flags is a bit of a mess: some are request types, and
others are just modifiers. Clean this up by splitting it into
->cmd_type and ->cmd_flags. This allows introduction of generic
Linux block message types, useful for sending generic Linux commands
to block devices.

Signed-off-by: Jens Axboe <axboe@suse.de>

[S390] dasd PAV enabling.

The subsystem check in the PAV code is incorrect, it enables PAV
per device instead of per subsystem.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd calls kzalloc while holding a spinlock.

The dasd function dasd_set_uid calls kzalloc while holding the
dasd_devmap_lock. Rearrange the code to do the memory allocation
outside the lock.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] Fix sparse warnings.

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

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[S390] add PAV support to the dasd driver.

Add support for parallel-access-volumes to the dasd driver. This
allows concurrent access to dasd devices with multiple channel
programs.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd whitespace and other cosmetics.

Dasd code cleanup: 1) remove white space, 2) remove the emacs override
sections, and 3) use kzalloc instead of kmalloc.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] dasd_eckd_dump_sense bug.

The ccw dump function dasd_eckd_dump_ccw_range can crash because
it does not take care about the IDAL flag in the ccw.
Check for IDALs flag set in CCW and follow the indirect list to
print the data that is refered by the ccw.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[PATCH] s390: dasd device identifiers

Generate new sysfs-attribute 'uid' that contains an device specific unique
identifier. This can be used to identity multiple ALIASES of the same
physical device (PAV). In addition the sysfs-attributes 'vendor' (containing
the manufacturer of the device) and 'alias' (identify alias or base device) is
added. This is first part of PAV support in LPAR (also valid on zVM).

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: use normal switch statement for ioctls in dasd_ioctlc

Add an ->ioctl method to the dasd_discipline structure. This allows to apply
the same kind of cleanups the last patch applied to dasd_ioctl.c to
dasd_eckd.c (the only dasd discipline with special ioctls) aswell.

Again lots of code removed. During auditing the ioctls I found two fishy
return value propagations from copy_{from,to}_user, maintainers please check
those, I've marked them with XXX comments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: Remove CVS generated information

- Remove all CVS generated information like e.g. revision IDs from
drivers/s390 and include/asm-s390 (none present in arch/s390).

- Add newline at end of arch/s390/lib/Makefile to avoid diff message.

Acked-by: Andreas Herrmann <aherrman@de.ibm.com>
Acked-by: Frank Pavlic <pavlic@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: cleanup Kconfig

Sanitize some s390 Kconfig options. We have ARCH_S390, ARCH_S390X,
ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT. Replace these 6 options by
S390, 64BIT and COMPAT.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: dasd failfast support

To properly support multipath-failover handling, the linux block layer has
introduced a special request flag, 'REQ_FAILFAST'. This flag is now used to
return requests immediately in case the device is not operational.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] s390: don't pad cdl blocks for write requests

The first blocks on a cdl formatted dasd device are smaller than the blocksize
of the device. Read requests are padded with a 'e5' pattern. Write requests
should not pad the (user) buffer with 'e5' because a write request is not
allowed to modify the buffer.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!