The dasd_open function uses the private_data pointer of the gendisk to
find the dasd_block structure that matches the gendisk. When a DASD
device is set offline, we set the private_data pointer of the gendisk
to NULL and later remove the dasd_block structure, but there is still
a small race window, in which dasd_open could first read a pointer
from the private_data field and then try to use it, after the structure
has already been freed.
To close this race window, we will store a pointer to the dasd_devmap
structure of the base device in the private_data field. The devmap
entries are not deleted, and we already have proper locking and
reference counting in place, so that we can safely get from a devmap
pointer to the dasd_device and dasd_block structures of the device.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The dasd and dcssblk drivers gained the big
kernel lock in the recent pushdown from the
block layer, but they don't really need it,
so remove the calls without a replacement.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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>
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>
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>
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>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
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>
All of the ioctls are compatible. Just enable them.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
The function shouldn't have existed in the first place (not MSS-aware).
Introduce a new function ccw_device_get_id() that extracts the
ccw_dev_id structure of a ccw device and convert all users of
_ccw_device_get_device_number to ccw_device_get_id.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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>
Use kzalloc to get a zeroed buffer for the structure returned to user space by
the BIODASDINFO2 ioctl. Not all fields are set up, e.g. the read_devno is
missing.
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>
Now that there are no more users of the awkward dynamic ioctl hack we can
remove the code to support it.
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>
dasd_cmd just implements three ioctls which are wrappers around functionality
in the core kernel or other modules. When merging those into dasd_mod they
just add 22 lines of code which is far less than the amount of code removed in
the last two patches, and which doesn't spill into another 4k pages when build
modular, while removing a 128lines module.
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>
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>
Handle ioctls implemented in dasd_ioctl through the normal switch statement
that most drivers use instead of the awkward dasd_ioctl_no_register routine.
This avoids searching a linear list on every call to dasd_ioctl(), and allows
to give the various ioctl implementation functions sane prototypes, aswell as
moving the check for bdev->bd_disk->private_data from the individual functions
to dasd_ioctl. (I think it can't actually every be NULL, but let's keep that
for later)
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>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The open_count is increased for every opener, that includes the blkdev_get in
dasd_scan_partitions. This tampers the open_count in BIODASDINFO. Hide the
internal open from user-space.
Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@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>
- 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>
Add a compat_ioctl method to the dasd driver so the last entries in
arch/s390/kernel/compat_ioctl.c can go away. Unlike the previous attempt this
one does not replace the ioctl method with an unlocked_ioctl method so that
the ioctl_by_bdev calls in s390 partition code continue to work.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
HDIO_GETGEO is implemented in most block drivers, and all of them have to
duplicate the code to copy the structure to userspace, as well as getting
the start sector. This patch moves that to common code [1] and adds a
->getgeo method to fill out the raw kernel hd_geometry structure. For many
drivers this means ->ioctl can go away now.
[1] the s390 block drivers are odd in this respect. xpram sets ->start
to 4 always which seems more than odd, and the dasd driver shifts
the start offset around, probably because of it's non-standard
sector size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@suse.de>
Cc: <mike.miller@hp.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The IOCTL BIODASDPRRD had no return code for 'profiling is inactive' and
therefore tunedasd wrote misleading message for request-counter = 0.
Introduce return-code EIO for inactive profiling.
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>
Reintroduce a read-only copy of the devmap features in the device struct.
This is necessary to solve a deadlock on the dasd_devmap_lock which is
acquired by dasd_get_features called from the dasd tasklet. The current
implementation of devmap doesn't allow to call any devmap function from
interrupt or softirq context.
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>
The independent read-only flags in devmap, dasd_device and gendisk are not
kept in sync. Use one bit per feature in the dasd driver and keep that bit in
sync with the gendisk bit.
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>
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!
Stefan Weinhuber