Several processes may concurrently try to create a group device
from the same ccw_device(s). Add locking arround the drvdata
access to prevent race conditions.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (81 commits)
[S390] remove duplicated #includes
[S390] cpumask: use mm_cpumask() wrapper
[S390] cpumask: Use accessors code.
[S390] cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.
[S390] cpumask: remove cpu_coregroup_map
[S390] fix clock comparator save area usage
[S390] Add hwcap flag for the etf3 enhancement facility
[S390] Ensure that ipl panic notifier is called late.
[S390] fix dfp elf hwcap/facility bit detection
[S390] smp: perform initial cpu reset before starting a cpu
[S390] smp: fix memory leak on __cpu_up
[S390] ipl: Improve checking logic and remove switch defaults.
[S390] s390dbf: Remove needless check for NULL pointer.
[S390] s390dbf: Remove redundant initilizations.
[S390] use kzfree()
[S390] BUG to BUG_ON changes
[S390] zfcpdump: Prevent zcore from beeing built as a kernel module.
[S390] Use csum_partial in checksum.h
[S390] cleanup lowcore.h
[S390] eliminate ipl_device from lowcore
...
For a ccw group device unbinding it from its driver should do the
same as a call to ungroup, since this virtual device can not exist
without a driver.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Some sanity checks in the ccw group driver test the output of
container_of macros to be !NULL. Test the input parameters instead.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In case the ccw group driver refuses to set a device [on|off]line,
we should transmit the return code to the caller.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The only way for a sysfs attribute to remove itself (without
deadlock) is to use the sysfs_schedule_callback() interface.
Vegard Nossum discovered that a poorly written sysfs ->store
callback can repeatedly schedule remove callbacks on the same
device over and over, e.g.
$ while true ; do echo 1 > /sys/devices/.../remove ; done
If the 'remove' attribute uses the sysfs_schedule_callback API
and also does not protect itself from concurrent accesses, its
callback handler will be called multiple times, and will
eventually attempt to perform operations on a freed kobject,
leading to many problems.
Instead of requiring all callers of sysfs_schedule_callback to
implement their own synchronization, provide the protection in
the infrastructure.
Now, sysfs_schedule_callback will only allow one scheduled
callback per kobject. On subsequent calls with the same kobject,
return -EAGAIN.
This is a short term fix. The long term fix is to allow sysfs
attributes to remove themselves directly, without any of this
callback hokey pokey.
[cornelia.huck@de.ibm.com: s390 ccwgroup bits]
Reported-by: vegard.nossum@gmail.com
Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Ensure atomicity of ungroup operation to prevent concurrent ungroup
and online processing which may lead to use-after-release situations.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert most s390 users setting bus_id to dev_set_name().
css and ccw busses are deferred since they need some special
treatment.
Signed-off-by: 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>
Since 16f7f9564c, we've seen
oopses when grouping/ungrouping devices:
Unable to handle kernel pointer dereference at virtual kernel address 0000000000
114000
Oops: 0004 [#1] PREEMPT SMP
Modules linked in: bonding qeth_l2 dm_multipath sunrpc qeth_l3 dm_mod qeth chsc_
sch ccwgroup
CPU: 1 Not tainted 2.6.26-29.x.20080815-s390xdefault #1
Process iperf (pid: 24412, task: 000000003f446038, ksp: 000000003c929e08)
Krnl PSW : 0404d00180000000 000003e00006f6e6 (qeth_irq+0xda/0xb28 [qeth])
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 0000000000000000 000003e000000003 0000000000000000 0000000000114ccc
000000003fb82e48 000003e00006f60c 000000000000000c 000000003ce72100
0000000000114944 000000003fb82e48 0000000000114ccc 000000003fe8fd28
000003e000066000 000003e000076128 000000003fe8fdb8 000000003fe8fd28
Krnl Code: 000003e00006f6da: bf3f2024 icm %r3,15,36(%r2)
000003e00006f6de: a774023c brc 7,3e00006fb56
000003e00006f6e2: a7280000 lhi %r2,0
>000003e00006f6e6: 5020a1a0 st %r2,416(%r10)
000003e00006f6ea: 58109000 l %r1,0(%r9)
000003e00006f6ee: a7111000 tmll %r1,4096
000003e00006f6f2: a77400f9 brc 7,3e00006f8e4
000003e00006f6f6: 8810000c srl %r1,12
Call Trace:
([<000000003fe8fd20>] 0x3fe8fd20)
[<000000000033bf2a>] ccw_device_call_handler+0xb2/0xd8
[<0000000000339e1c>] ccw_device_irq+0x124/0x164
[<0000000000339758>] io_subchannel_irq+0x8c/0x118
[<00000000003309ba>] do_IRQ+0x192/0x1bc
[<0000000000114f66>] io_return+0x0/0x8
[<00000000001149cc>] sysc_do_svc+0x0/0x22
([<0000000000114a18>] sysc_noemu+0x10/0x16)
[<00000200002e047c>] 0x200002e047c
Last Breaking-Event-Address:
[<000003e00006f6d6>] qeth_irq+0xca/0xb28 [qeth]
The problem is that dev->driver_data for a ccw device is NULL,
while it should point to the ccwgroup device it is a member of.
This happened due to incorrect cleanup if creating a ccwgroup
device failed because the ccw devices were already grouped.
Fix this by setting cdev[i] to NULL in the error handling of
ccwgroup_create_from_string() after we give up our reference and
by checking if the driver_data points to the ccwgroup device in
ccwgroup_release() just to be really sure.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix ccw group device initialization: initialize device object before
using reference counting during cleanup.
Fixes the following message when group device initialization fails
(e.g. because too few devices where specified):
kobject: '<NULL>' (..): is not initialized, yet kobject_put() is
being called.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (53 commits)
tcp: Overflow bug in Vegas
[IPv4] UFO: prevent generation of chained skb destined to UFO device
iwlwifi: move the selects to the tristate drivers
ipv4: annotate a few functions __init in ipconfig.c
atm: ambassador: vcc_sf semaphore to mutex
MAINTAINERS: The socketcan-core list is subscribers-only.
netfilter: nf_conntrack: padding breaks conntrack hash on ARM
ipv4: Update MTU to all related cache entries in ip_rt_frag_needed()
sch_sfq: use del_timer_sync() in sfq_destroy()
net: Add compat support for getsockopt (MCAST_MSFILTER)
net: Several cleanups for the setsockopt compat support.
ipvs: fix oops in backup for fwmark conn templates
bridge: kernel panic when unloading bridge module
bridge: fix error handling in br_add_if()
netfilter: {nfnetlink,ip,ip6}_queue: fix skb_over_panic when enlarging packets
netfilter: x_tables: fix net namespace leak when reading /proc/net/xxx_tables_names
netfilter: xt_TCPOPTSTRIP: signed tcphoff for ipv6_skip_exthdr() retval
tcp: Limit cwnd growth when deferring for GSO
tcp: Allow send-limited cwnd to grow up to max_burst when gso disabled
[netdrvr] gianfar: Determine TBIPA value dynamically
...
Instead of having each driver for ccwgroup slave device parsing the
input itself and calling ccwgroup_create(), introduce a new function
ccwgroup_create_from_string() and handle parsing inside the ccwgroup
core.
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
None of these files use any of the functionality promised by
asm/semaphore.h. It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
This intendeds to make proper shutdown of qeth devices easier.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There are two ways for a ccwgroup device to be unregistered:
Via the ungroup attribute, or when on of the slave devices is killed
by a machine check. As we have to unregister the ccwgroup device
via a callback, we'll now have to check whether it hasn't been
already unregistered because of a machine check.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Set the owner field in the embedded struct device_driver to the
value provided in the {css,ccw,ccwgroup}_driver.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Also define helpers sch_{g,s}et_cdev() to make the intention more
clear.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- Introduce to_cssdriver.
- Use to_xxx instead of container_of where possible.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (75 commits)
PM: merge device power-management source files
sysfs: add copyrights
kobject: update the copyrights
kset: add some kerneldoc to help describe what these strange things are
Driver core: rename ktype_edd and ktype_efivar
Driver core: rename ktype_driver
Driver core: rename ktype_device
Driver core: rename ktype_class
driver core: remove subsystem_init()
sysfs: move sysfs file poll implementation to sysfs_open_dirent
sysfs: implement sysfs_open_dirent
sysfs: move sysfs_dirent->s_children into sysfs_dirent->s_dir
sysfs: make sysfs_root a regular directory dirent
sysfs: open code sysfs_attach_dentry()
sysfs: make s_elem an anonymous union
sysfs: make bin attr open get active reference of parent too
sysfs: kill unnecessary NULL pointer check in sysfs_release()
sysfs: kill unnecessary sysfs_get() in open paths
sysfs: reposition sysfs_dirent->s_mode.
sysfs: kill sysfs_update_file()
...
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Comment a bunch of function in docbook style and convert existing
comments on structures to docbook.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
- Remove unneeded messages.
- Move some messages into the debug feature.
- Use dev_* where appropriate.
- Use "cio: " prefix consistently.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce a mutex for struct ccwgroup to prevent simuntaneous
register/unregister on the same ccwgroup device.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch (as868) adds a helper routine for device drivers that need
to set up a callback to perform some action in a different process's
context. This is intended for use by attribute methods that want to
unregister themselves or their parent device. Attribute method calls
are mutually exclusive with unregistration, so such actions cannot be
taken directly.
Two attribute methods are converted to use the new helper routine: one
for SCSI device deletion and one for System/390 ccwgroup devices.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use different kind of assignment to make sure gcc doesn't create code
that creates temp variables on the stack, assigns values to it and
copies the content of the whole temp variable to the destination.
This reduces stack usage of e.g. ccwgroup_driver_register from 976
to 48 bytes instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fail to create a ccwgroup device if a ccw device is passed in twice.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Work around the problem that a device cannot be unregistered from
driver_for_each_device() because of klist node refcounting: Get device
after device owned by the driver to be unregistered with driver_find_device()
and then unregister it. This works because driver_get_device() gets us out of
the region of the elevated klist node refcount. driver_find_device() will
always get the next device in the list after the found one has been
unregistered.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert all kmalloc + memset sequences in drivers/s390 to kzalloc usage.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.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>
- 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>
Hugh Dickins <hugh@veritas.com>
Fix the broken atomic_cmpxchg primitive. Add atomic_sub_and_test,
atomic64_sub_return, atomic64_sub_and_test, atomic64_cmpxchg,
atomic64_add_unless and atomic64_inc_not_zero. Replace old style
atomic_compare_and_swap by atomic_cmpxchg. Shorten the whole header by
defining most primitives with the two inline functions atomic_add_return and
atomic_sub_return.
In addition this patch contains the s390 related fixes of Hugh's "mm: fill
arch atomic64 gaps" patch.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The first of these changes s/hotplug/uevent/ was needed to
compile sn2_defconfig (ia64/sn). The other three files
changed are blind changes of all remaining bus_type.hotplug
references I could find to bus_type.uevent.
This patch attempts to finish similar changes made in the
gregkh-driver-kill-hotplug-word-from-driver-core Nov 22 patch.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make the interface for setting ccw group devices on-/offline consistent with
that for ccw devices: Check if the device driver provided a set_{on,off}line
function and just set the device on-/offline if not.
Signed-off-by: Cornelia Huck <cohuck@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>
add the helper and use it instead of open coding the klist_node_attached() check
(which is a layering violation IMHO)
idea by Alan Stern.
Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert the common I/O layer to use the klist interfaces.
This patch has been adapted from the previous version to the changed interface
semantics. Also, gcc 4.0 compile warnings have been removed.
Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: 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!
