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: NJan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NJan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NJan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NJan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: 5e2b17e7 ("s390/dasd: Add dynamic formatting support for ESE volumes")
Cc: stable@vger.kernel.org # 5.3+
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Reviewed-by: NJan Hoeppner <hoeppner@linux.ibm.com>
Reviewed-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NQian Cai <cai@lca.pw>
Reviewed-by: NJan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJan Höppner <hoeppner@linux.ibm.com>
Acked-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This reverts commit 7e64db15.

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: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: c729696b ("s390/dasd: Recognise data for ESE volumes")
Cc: <stable@vger.kernel.org> # 5.3
Reported-by: NFrank Heimes <frank.heimes@canonical.com>
Signed-off-by: NJan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Commit 4d284cac ("[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: NJan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Commit 72deb455 ("block: remove CONFIG_LBDAF") changes
sector_t to u64 unconditionaly, so apply '%llu' for print
sector_t variable.

Fixes: 72deb455 ("block: remove CONFIG_LBDAF")
Cc: linux-s390@vger.kernel.org
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

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   5843492c
     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: NPeter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Dan Carpenter reported the following:

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

During offline processing two worker threads are canceled without
freeing the device reference which leads to a hanging offline process.
Reviewed-by: NJan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NJan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

PTR_RET is deprecated, use PTR_ERR_OR_ZERO instead.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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.orgSigned-off-by: NSebastian Ott <sebott@linux.ibm.com>
Reviewed-by: NStefan Haberland <sth@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NPeter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: NStefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Use 'seq_printf(m, "...%*phN...")' instead of duplicating its
implementation.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NStefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NStefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: NJan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NJan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NStefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: NJan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Rename dasd_raw_build_cp() to dasd_eckd_build_cp_raw() to fit the
scheme.
Reviewed-by: NStefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: NJan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NStefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: NJan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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

Some storage servers might not support the query host access feature.
Check if the corresponding feature code is set.
Signed-off-by: NStefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

trivial fix to spelling mistake in literal string
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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

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

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: NStefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NJan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

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: NStefan Haberland <sth@linux.vnet.ibm.com>
Reviewed-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: NJan Hoeppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>