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path: root/drivers/s390/char/sclp_vt220.c
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* s390/sclp_vt220: support magic sysrequestsHendrik Brueckner2015-08-261-1/+51
| | | | | | | | | | | | | | | | | | Implement magic sysrequest handling for the VT220 terminal (also known as the Integrated ASCII console on the HMC/SE). To invoke a "magic sysrequest" function, press "Ctrl+o" followed by a second character that designates the debugging function. The handling of the sysrq is scheduled away from the SCLP IRQ context; because large amounts of sysrq output might fill up the console buffers. The console might deadlock because it cannot empty the buffers while still in the receiving IRQ context. This behavior is the same as for the SCLP console. Reported-by: Horst Weber <hweber@de.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/sclp: reduce dependency on event type masksMartin Schwidefsky2014-09-251-4/+0
| | | | | | | | | | | | | | | The event type masks can change asynchronously. These changes are reported by SCLP to the OS by state-change events which are retrieved with the read event data command. The SCLP driver has a request queue, there is a window where the read event data request has not completed yet but the SCLP console drivers are trying to queue output requests. As the masks are not updated yet the requests are discarded. The simplest fix is to queue the console requests independent of the event type masks and rely on SCLP to return with an error code if a specific event type is not available. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/sclp_vt220: Enable ASCII console per defaultPeter Oberparleiter2014-06-101-2/+0
| | | | | | | | | | | | | | | When you want to use the HMC's ASCII console as console device for a z/VM guest you have to specify console=ttyS1 on the kernel command line. But it won't work until you specify conmode=sclp as well. This behavior is inconsistent with the use of the ASCII console as TTY device which works on z/VM without the need to specify a conmode. Fix this inconsistency by removing the check for conmode=sclp in the ASCII console registration function. Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/sclp_vt220: Fix kernel panic due to early terminal inputPeter Oberparleiter2014-04-111-3/+11
| | | | | | | | | | | | | | | | | | | | A kernel panic might occur when there is terminal input available via the SCLP VT220 interface at an early time during the boot process. The processing of terminal input requires prior initialization which is done via an early_initcall function (init_workqueues) while the SCLP VT220 driver registers for terminal input during a console_initcall function (sclp_vt220_con_init). When there is terminal input available via the SCLP interface between console_initcall and early_initcall, a null pointer dereference occurs (system_wq is null). Fix this problem by moving the registration for terminal input to a device_initcall function (sclp_vt220_tty_init). Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/sclp: add parameter to specify number of buffer pagesMartin Schwidefsky2013-06-261-5/+34
| | | | | | | | | | | | | | | | Add a kernel parameter to be able to specify the number of pages to be used as output buffer by the line-mode sclp driver and the vt220 sclp driver. The current number of output pages is 6, if the service element is unavailable the boot messages alone can fill up the output buffer. If this happens the system blocks until the service element is working again. For a large LPAR with many devices it is sensible to have the ability to increase the output buffer size. To help to debug this situation add a counter for the page-pool-empty situation and make it available as a sclp driver attribute. To avoid the system to stall until the service element works again add another kernel parameter to allow to drop output buffers. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* TTY: add tty_port_tty_wakeup helperJiri Slaby2013-03-181-7/+1
| | | | | | | | | | | | It allows for cleaning up on a considerable amount of places. They did port_get, wakeup, kref_put. Now the only thing needed is to call tty_port_tty_wakeup which does exactly that. One exception is ifx6x60 where tty_wakeup was open-coded. We now call tty_wakeup properly there. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: switch tty_flip_buffer_pushJiri Slaby2013-01-151-7/+1
| | | | | | | | | | | | | | | | | | | | Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: move low_latency to tty_portJiri Slaby2013-01-151-1/+1
| | | | | | | | | | One point is to have less places where we actually need tty pointer. The other is that low_latency is bound to buffer processing and buffers are now in tty_port. So it makes sense to move low_latency to tty_port too. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: switch tty_insert_flip_stringJiri Slaby2013-01-151-1/+1
| | | | | | | | | | | | Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. tty_insert_flip_string this time. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: call tty_port_destroy in the rest of driversJiri Slaby2012-11-151-0/+2
| | | | | | | | | | | | | | | | After commit "TTY: move tty buffers to tty_port", the tty buffers are not freed in some drivers. This is because tty_port_destructor is not called whenever a tty_port is freed. This was an assumption I counted with but was unfortunately untrue. So fix the drivers to fulfil this assumption. To be sure, the TTY buffers (and later some stuff) are gone along with the tty_port, we have to call tty_port_destroy at tear-down places. This is mostly where the structure containing a tty_port is freed. This patch does exactly that -- put tty_port_destroy at those places. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: use tty_port_link_deviceJiri Slaby2012-08-131-0/+1
| | | | | | | | | | | | | | So now for those drivers that can use neither tty_port_install nor tty_port_register_driver but still have tty_port available before tty_register_driver we use newly added tty_port_link_device. The rest of the drivers that still do not provide tty_struct <-> tty_port link will have to be converted to implement tty->ops->install. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: sclp_vt220, remove unused allocationJiri Slaby2012-04-091-8/+1
| | | | | | | | | | | | 80 bytes which are allocated in tty->ops->open and assigned to tty->driver_data are never used. Remove that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: sclp_vt220, add tty_portJiri Slaby2012-04-091-10/+14
| | | | | | | | | | | | | tty_port will hold tty buffers in the future. So we need to have it even here. The only needed member here is tty, so let us store it in the structure now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* TTY: remove re-assignments to tty_driver membersJiri Slaby2012-03-081-1/+0
| | | | | | | | | | | | | | All num, magic and owner are set by alloc_tty_driver. No need to re-set them on each allocation site. pti driver sets something different to what it passes to alloc_tty_driver. It is not a bug, since we don't use the lines parameter in any way. Anyway this is fixed, and now we do the right thing. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h 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>
* [S390] sclp_vt220: set initial terminal window sizeHendrik Brueckner2010-01-271-0/+4
| | | | | | | | | | | When opening a SCLP VT220 terminal, the terminal window size is not initialized (defaults to zero). Since the SCLP VT220 terminal supports only 80x24, explicitly set the window size to prevent (n)curses applications from guessing the default setting. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp_vt220 build fixMichael Holzheu2009-10-141-15/+15
| | | | | | | | | | | | Fix this build error: next-20091013 randconfig build on s390x build breaks with drivers/s390/built-in.o:(.data+0x3354): undefined reference to `sclp_vt220_pm_event_fn' Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Michael Holzheu <michael.holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] vt220 console: convert from bootmem to slabHeiko Carstens2009-06-221-13/+5
| | | | | | | | The slab allocator is earlier available so convert the bootmem allocations to slab/gfp allocations. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] pm: power management support for SCLP drivers.Michael Holzheu2009-06-161-39/+79
| | | | | | | | | | | | | | | | | | | | | | | The SCLP base driver defines a new notifier call back for all upper level SCLP drivers, like the SCLP console, etc. This guarantees that in suspend first the upper level drivers are suspended and afterwards the SCLP base driver. For resume it is the other way round. The SCLP base driver itself registers a new platform device at the platform bus and gets PM notifications via the dev_pm_ops. In suspend, the SCLP base driver switches off the receiver and sender mask This is done in sclp_deactivate(). After suspend all new requests will be rejected with -EIO and no more interrupts will be received, because the masks are switched off. For resume the sender and receiver masks are reset in the sclp_reactivate() function. When the SCLP console is suspended, all new messages are cached in the sclp console buffers. In resume, all the cached messages are written to the console. In addition to that we have an early resume function that removes the cached messages from the suspend image. Signed-off-by: Michael Holzheu <holzheu@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp vt220: fix compile warningHeiko Carstens2008-12-251-17/+16
| | | | | | | | | | get rid of this one: CC drivers/s390/char/sclp_vt220.o drivers/s390/char/sclp_vt220.c:588: warning: '__sclp_vt220_flush_buffer' defined but not used Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] console flush on panic / rebootHolger Smolinski2008-10-101-8/+18
| | | | | | | | | | | | | | The s390 console drivers use the unblank callback of the console structure to flush the console buffer. In case of a panic or a reboot the CPU doing the callback can block on the console i/o. The other CPUs in the system continue to work. For panic this is not a good idea. Replace the unblank callback with proper panic/reboot notifier. These get called after all but one CPU have been stopped. Signed-off-by: Holger Smolinski <Holger.Smolinski@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Cleanup sclp printk messages.Martin Schwidefsky2008-07-141-6/+1
| | | | | Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] sclp: simplify vt220 cleanup logicPeter Oberparleiter2008-07-141-27/+28
| | | | | | | | | | | | Fix a number of sclp_vt220 cleanup problems: * fix list_empty check after list_del() * mark init-only flag as __initdata * remove implicit dependency between slab_available() and num_pages * straighten multiple init handling (use init count) 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] vt220 console, initialize list head before useCarsten Otte2008-06-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a null pointer dereference during initialisation when no sclp event facility is available: sclp vt220 tty driver: could not register vt220 - sclp_register returned -5 Unable to handle kernel paging request at virtual user address 0000000000000000 Oops: 0004 [#1] PREEMPT SMP Modules linked in: CPU: 0 Not tainted 2.6.26-rc3-kvm-bigiron-00968-gd939e93-dirty #30 Process swapper (pid: 0, task: 0000000000600be0, ksp: 000000000064a000) Krnl PSW : 0400000180000000 0000000000320d8c (sclp_unregister+0x48/0x8c) R:0 T:1 IO:0 EX:0 Key:0 M:0 W:0 P:0 AS:0 CC:0 PM:0 EA:3 Krnl GPRS: 0000000000000000 0000000000000000 0000000000630478 0700000000649c20 0000000000000000 0000000000433060 000000000064a660 0000000002e26000 00000000006db000 0000000000000000 0000000000a78578 0000000000649b80 0000000000630dc0 000000000044fa20 0000000000320d76 0000000000649b80 Krnl Code: 0000000000320d7c: e310c0080004 lg %r1,8(%r12) 0000000000320d82: b9040032 lgr %r3,%r2 0000000000320d86: c02000187b79 larl %r2,630478 >0000000000320d8c: e34010000024 stg %r4,0(%r1) 0000000000320d92: e31040080024 stg %r1,8(%r4) 0000000000320d98: c01100200200 lgfi %r1,2097664 0000000000320d9e: e310c0080024 stg %r1,8(%r12) 0000000000320da4: c01100100100 lgfi %r1,1048832 Call Trace: ([<0000000000320d76>] sclp_unregister+0x32/0x8c) [<00000000006657b4>] __sclp_vt220_cleanup+0xc4/0xe0 [<000000000066595c>] __sclp_vt220_init+0x18c/0x1a0 [<0000000000665aba>] sclp_vt220_con_init+0x42/0x68 [<00000000006601ca>] console_init+0x4e/0x68 [<000000000064acae>] start_kernel+0x3a2/0x4dc [<0000000000100020>] _stext+0x20/0x80 INFO: lockdep is turned off. Last Breaking-Event-Address: [<000000000041f964>] _spin_lock_irqsave+0xb0/0xb4 <4>---[ end trace 31fd0ba7d8756001 ]--- The issue is caused by a list_empty() check in __sclp_vt220_cleanup, which usually fails on non-initialized list heads that contain {NULL,NULL} instead. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp_vt220: fix scheduling while atomic bug.Heiko Carstens2008-05-301-20/+7
| | | | | | | | | | | | | | | | | The driver incorrectly assumed that putchar will only be called from schedulable process context and therefore blocked and waited if no free output buffers where available. Since putchar may also be called from BH context this may lead to deadlocks. To fix this just return the number of characters accepted and let the upper layer handle the rest. The console write function will busy wait (sclp_sync_wait) until a buffer is available again. Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390 tty: Prepare for put_char to return success/failAlan Cox2008-04-301-1/+5
| | | | | | | | | | | | | Put the changes into the drivers first. This will still compile/work but produce a warning if bisected so can still be debugged Signed-off-by: Alan Cox <alan@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [S390] sclp: Get rid of in_atomic() use.Heiko Carstens2008-04-171-7/+6
| | | | | | | | | | Reintroduces in_interrupt() check in sclp_tty code. Add may_schedule parameter to vt220 write function, so we can let the write function know if it may schedule or not. So we disallow scheduling for all console calls and may allow them for tty calls. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] sclp_vt220: speed up console output for interactive workChristian Borntraeger2008-03-051-1/+1
| | | | | | | | | | Currently an output buffer can wait up to HZ/2 until the buffer is flushed. The wait time is noticeable in interactive tools like mc. Change the value to HZ/20, which seems enough for interactive work. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp: clean up send/receive naming schemePeter Oberparleiter2008-02-191-1/+1
| | | | | | | | | Make state change events adjust the correct mask by cleaning up naming inconsistencies. Also remove chance for lockup by removing unnecessary mask related check before reading events. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp_vt220: Fix vt220 initializationChristian Borntraeger2008-02-091-13/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are two problems in the vt220 intialization: o Currently the vt220 console looses early printk events until the the vt220 tty is registered. o console should work if tty_register fails sclp_vt220_con_init calls __sclp_vt220_init and register_console. It does not register the driver with the sclp core code via sclp_register. That results in an sclp_send_mask=0. Therefore, __sclp_vt220_emit will reject buffers with EIO. Unfortunately register_console will cause the printk buffer to be sent to the console and, therefore, every early message gets dropped. The sclp_send_mask is set later during boot, when sclp_vt220_tty_init calls sclp_register. The solution is to move the sclp_register call from sclp_vt220_tty_init to __sclp_vt220_init. This makes sure that the console is properly registered with the sclp subsystem before the first log buffer messages are passed to the vt220 console. We also adopt the cleanup on error to keep the console alive if tty_register fails. Thanks to Peter Oberparleiter and Heiko Carstens for review and ideas for improvement. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp_tty/sclp_vt220: Fix scheduling while atomicChristian Borntraeger2008-02-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Under load the following bug message appeared while using sysrq-t: BUG: scheduling while atomic: bash/3662/0x00000004 0000000000105b74 000000003ba17740 0000000000000002 0000000000000000 000000003ba177e0 000000003ba17758 000000003ba17758 0000000000105bfe 0000000000817ba8 000000003f2a5350 0000000000000000 0000000000000000 000000003ba17740 000000000000000c 000000003ba17740 000000003ba177b0 0000000000568630 0000000000105bfe 000000003ba17740 000000003ba17790 Call Trace: ([<0000000000105b74>] show_trace+0x13c/0x158) [<0000000000105c58>] show_stack+0xc8/0xfc [<0000000000105cbc>] dump_stack+0x30/0x40 [<000000000012a0c8>] __schedule_bug+0x84/0x94 [<000000000056234e>] schedule+0x5ea/0x970 [<0000000000477cd2>] __sclp_vt220_write+0x1f6/0x3ec [<0000000000477f00>] sclp_vt220_con_write+0x38/0x48 [<0000000000130b4a>] __call_console_drivers+0xbe/0xd8 [<0000000000130bf0>] _call_console_drivers+0x8c/0xd0 [<0000000000130eea>] release_console_sem+0x1a6/0x2fc [<0000000000131786>] vprintk+0x262/0x480 [<00000000001319fa>] printk+0x56/0x68 [<0000000000125aaa>] print_cfs_rq+0x45e/0x4a4 [<000000000012614e>] sched_debug_show+0x65e/0xee8 [<000000000012a8fc>] show_state_filter+0x1cc/0x1f0 [<000000000044d39c>] sysrq_handle_showstate+0x2c/0x3c [<000000000044d1fe>] __handle_sysrq+0xae/0x18c [<00000000002001f2>] write_sysrq_trigger+0x8a/0x90 [<00000000001f7862>] proc_reg_write+0x9a/0xc4 [<00000000001a83d4>] vfs_write+0xb8/0x174 [<00000000001a8b88>] sys_write+0x58/0x8c [<0000000000112e7c>] sysc_noemu+0x10/0x16 [<0000020000116f68>] 0x20000116f68 The problem seems to be, that with a full console buffer, release_console_sem disables interrupts with spin_lock_irqsave and then calls the console function without enabling interrupts. __sclp_vt220_write checks for in_interrupt, to decide if it can schedule. It should check for in_atomic instead. The same is true for sclp_tty.c. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Fix sclp_vt220 error handling.Heiko Carstens2007-07-271-21/+40
| | | | | | | | Also convert to slab_is_available() as an indicator if get_zeroed_page() will work or not. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Get rid of new section mismatch warnings.Heiko Carstens2007-07-271-2/+1
| | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] sclp: fix coding style.Stefan Haberland2007-04-271-4/+4
| | | | | | | | | Use only capital letters for defines. Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> 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>
* [PATCH] remove many unneeded #includes of sched.hTim Schmielau2007-02-141-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [S390] Convert memory detection into C code.Heiko Carstens2007-02-051-1/+1
| | | | | | | | | | | | | | Hopefully this will make it more maintainable and less error prone. Code makes use of search_exception_tables(). Since it calls this function before the kernel exeception table is sorted, there is an early call to sort_main_extable(). This way it's easy to use the already present infrastructure of fixup sections. Also this would allows to easily convert the rest of head[31|64].S into C code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Get rid of a lot of sparse warnings.Heiko Carstens2007-02-051-1/+1
| | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [PATCH] const struct tty_operationsJeff Dike2006-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | As part of an SMP cleanliness pass over UML, I consted a bunch of structures in order to not have to document their locking. One of these structures was a struct tty_operations. In order to const it in UML without introducing compiler complaints, the declaration of tty_set_operations needs to be changed, and then all of its callers need to be fixed. This patch declares all struct tty_operations in the tree as const. In all cases, they are static and used only as input to tty_set_operations. As an extra check, I ran an i386 allyesconfig build which produced no extra warnings. 53 drivers are affected. I checked the history of a bunch of them, and in most cases, there have been only a handful of maintenance changes in the last six months. serial_core.c was the busiest one that I looked at. Signed-off-by: Jeff Dike <jdike@addtoit.com> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] TTY layer buffering revampAlan Cox2006-01-101-10/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.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>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+785
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!
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