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Guilherme G. Piccoli 4ae46db99c s390/consoles: improve panic notifiers reliability
Currently many console drivers for s390 rely on panic/reboot notifiers
to invoke callbacks on these events. The panic() function disables local
IRQs, secondary CPUs and preemption, so callbacks invoked on panic are
effectively running in atomic context.

Happens that most of these console callbacks from s390 doesn't take the
proper care with regards to atomic context, like taking spinlocks that
might be taken in other function/CPU and hence will cause a lockup
situation.

The goal for this patch is to improve the notifiers reliability, acting
on 4 console drivers, as detailed below:

(1) con3215: changed a regular spinlock to the trylock alternative.

(2) con3270: also changed a regular spinlock to its trylock counterpart,
but here we also have another problem: raw3270_activate_view() takes a
different spinlock. So, we worked a helper to validate if this other lock
is safe to acquire, and if so, raw3270_activate_view() should be safe.

Notice though that there is a functional change here: it's now possible
to continue the notifier code [reaching con3270_wait_write() and
con3270_rebuild_update()] without executing raw3270_activate_view().

(3) sclp: a global lock is used heavily in the functions called from
the notifier, so we added a check here - if the lock is taken already,
we just bail-out, preventing the lockup.

(4) sclp_vt220: same as (3), a lock validation was added to prevent the
potential lockup problem.

Besides (1)-(4), we also removed useless void functions, adding the
code called from the notifier inside its own body, and changed the
priority of such notifiers to execute late, since they are "heavyweight"
for the panic environment, so we aim to reduce risks here.
Changed return values to NOTIFY_DONE as well, the standard one.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Link: https://lore.kernel.org/r/20220427224924.592546-14-gpiccoli@igalia.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2022-05-06 20:45:13 +02:00
Yu Liao 4f45c37ffd s390: cleanup timer API use
cleanup the s390's use of the timer API
- del_timer() contains timer_pending() condition
- mod_timer(timer, expires) is equivalent to:

	del_timer(timer);
	timer->expires = expires;
	add_timer(timer);

If the timer is inactive it will be activated, using add_timer() on
condition !timer_pending(&private->timer) is redundant.

Just cleanup, no logic change.

Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Link: https://lore.kernel.org/r/20220322030057.1243196-1-liaoyu15@huawei.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-03-27 22:18:39 +02:00
Linus Torvalds 2bb919b62f s390 updates for the 5.14 merge window
- Rework inline asm to get rid of error prone "register asm" constructs,
   which are problematic especially when code instrumentation is enabled. In
   particular introduce and use register pair union to allocate even/odd
   register pairs. Unfortunately this breaks compatibility with older
   clang compilers and minimum clang version for s390 has been raised to 13.
   https://lore.kernel.org/linux-next/CAK7LNARuSmPCEy-ak0erPrPTgZdGVypBROFhtw+=3spoGoYsyw@mail.gmail.com/
 
 - Fix gcc 11 warnings, which triggered various minor reworks all over
   the code.
 
 - Add zstd kernel image compression support.
 
 - Rework boot CPU lowcore handling.
 
 - De-duplicate and move kernel memory layout setup logic earlier.
 
 - Few fixes in preparation for FORTIFY_SOURCE performing compile-time
   and run-time field bounds checking for mem functions.
 
 - Remove broken and unused power management support leftovers in s390
   drivers.
 
 - Disable stack-protector for decompressor and purgatory to fix buildroot
   build.
 
 - Fix vt220 sclp console name to match the char device name.
 
 - Enable HAVE_IOREMAP_PROT and add zpci_set_irq()/zpci_clear_irq() in
   zPCI code.
 
 - Remove some implausible WARN_ON_ONCEs and remove arch specific counter
   transaction call backs in favour of default transaction handling in
   perf code.
 
 - Extend/add new uevents for online/config/mode state changes of
   AP card / queue device in zcrypt.
 
 - Minor entry and ccwgroup code improvements.
 
 - Other small various fixes and improvements all over the code.
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Merge tag 's390-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Rework inline asm to get rid of error prone "register asm"
   constructs, which are problematic especially when code
   instrumentation is enabled.

   In particular introduce and use register pair union to allocate
   even/odd register pairs. Unfortunately this breaks compatibility with
   older clang compilers and minimum clang version for s390 has been
   raised to 13.

     https://lore.kernel.org/linux-next/CAK7LNARuSmPCEy-ak0erPrPTgZdGVypBROFhtw+=3spoGoYsyw@mail.gmail.com/

 - Fix gcc 11 warnings, which triggered various minor reworks all over
   the code.

 - Add zstd kernel image compression support.

 - Rework boot CPU lowcore handling.

 - De-duplicate and move kernel memory layout setup logic earlier.

 - Few fixes in preparation for FORTIFY_SOURCE performing compile-time
   and run-time field bounds checking for mem functions.

 - Remove broken and unused power management support leftovers in s390
   drivers.

 - Disable stack-protector for decompressor and purgatory to fix
   buildroot build.

 - Fix vt220 sclp console name to match the char device name.

 - Enable HAVE_IOREMAP_PROT and add zpci_set_irq()/zpci_clear_irq() in
   zPCI code.

 - Remove some implausible WARN_ON_ONCEs and remove arch specific
   counter transaction call backs in favour of default transaction
   handling in perf code.

 - Extend/add new uevents for online/config/mode state changes of AP
   card / queue device in zcrypt.

 - Minor entry and ccwgroup code improvements.

 - Other small various fixes and improvements all over the code.

* tag 's390-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (91 commits)
  s390/dasd: use register pair instead of register asm
  s390/qdio: get rid of register asm
  s390/ioasm: use symbolic names for asm operands
  s390/ioasm: get rid of register asm
  s390/cmf: get rid of register asm
  s390/lib,string: get rid of register asm
  s390/lib,uaccess: get rid of register asm
  s390/string: get rid of register asm
  s390/cmpxchg: use register pair instead of register asm
  s390/mm,pages-states: get rid of register asm
  s390/lib,xor: get rid of register asm
  s390/timex: get rid of register asm
  s390/hypfs: use register pair instead of register asm
  s390/zcrypt: Switch to flexible array member
  s390/speculation: Use statically initialized const for instructions
  virtio/s390: get rid of open-coded kvm hypercall
  s390/pci: add zpci_set_irq()/zpci_clear_irq()
  scripts/min-tool-version.sh: Raise minimum clang version to 13.0.0 for s390
  s390/ipl: use register pair instead of register asm
  s390/mem_detect: fix tprot() program check new psw handling
  ...
2021-07-04 12:17:38 -07:00
Andy Shevchenko f39650de68 kernel.h: split out panic and oops helpers
kernel.h is being used as a dump for all kinds of stuff for a long time.
Here is the attempt to start cleaning it up by splitting out panic and
oops helpers.

There are several purposes of doing this:
- dropping dependency in bug.h
- dropping a loop by moving out panic_notifier.h
- unload kernel.h from something which has its own domain

At the same time convert users tree-wide to use new headers, although for
the time being include new header back to kernel.h to avoid twisted
indirected includes for existing users.

[akpm@linux-foundation.org: thread_info.h needs limits.h]
[andriy.shevchenko@linux.intel.com: ia64 fix]
  Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com

Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Co-developed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:04 -07:00
Peter Oberparleiter 5602bf8a7b s390/sclp: Remove console power management support
Power management support was removed for s390 with
commit 394216275c ("s390: remove broken hibernate / power management
support").

Remove leftover sclp console-related power management code.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-18 16:41:20 +02:00
Vineeth Vijayan 8bc00c04d8 s390/sclp: use LIST_HEAD for Initialization
For static initialization of list_head variable, use LIST_HEAD
instead of INIT_LIST_HEAD function.

Suggested-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-07 15:24:57 +02:00
Vineeth Vijayan 7dd8ed0943 s390: use DEFINE_SPINLOCK for initialization
For static initialization of spinlock_t variable, use DEFINE_SPINLOCK
instead of explicitly calling spin_lock_init().

Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-07 15:24:56 +02:00
Peter Oberparleiter 98ce70b769 s390/sclp: increase sclp console line length
Kernel and console/TTY messages written to the SCLP line mode console
are wrapped at 80 characters per line by the associated SCLP driver.
This makes long lines of output difficult to read, and requires editing
of wrapped lines copied from the output device.

Neither the firmware interface used to access the SCLP console, nor the
HMC "Operating System Messages" web interface that displays these
messages require such a length limit. Also other operating systems such
as z/VM do not impose similar limits on messages they emit to the same
console device.

This patch therefore increases the limit to 320 characters per line to
make SCLP line mode console output more readable. As a result 99% of
lines written during a typical boot will not be wrapped, compared to
about 50% wrapped lines at 80 characters per line. Another positive
side-effect of this change is that the HMC console interface is able to
keep more messages in its history buffer due to fewer line-breaks being
generated.

In a worst case scenario this means that a 4k console buffer is emitted
with the last ~400 bytes empty (320 text + 78 headers). This is more
than offset by the fact that each line that is not truncated saves 78
header bytes in the buffer. As a result the actual number of emitted
buffers should be about the same as with the 80 character limit.

This patch also removes the differentiation between line lengths of
SCLP line mode output on z/VM and non-z/VM systems. While the z/VM
hypervisor adds a prefix in front of each line ('xx: ' where xx is the
number of the CPU issuing the message), adjusting Linux line lengths did
not significantly increase readability of console output, and makes even
less of a difference with longer lines.

Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-22 11:36:03 +01:00
Kees Cook c9602ee7d1 s390/sclp: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Instead of creating an external static
data variable, just define a separate callback which encodes the "force
restart" desire.

Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
[heiko.carstens@de.ibm.com: get rid of compile warning]
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-11-14 11:01:39 +01:00
Linus Torvalds d60a540ac5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:
 "Since Martin is on vacation you get the s390 pull request for the
  v4.15 merge window this time from me.

  Besides a lot of cleanups and bug fixes these are the most important
  changes:

   - a new regset for runtime instrumentation registers

   - hardware accelerated AES-GCM support for the aes_s390 module

   - support for the new CEX6S crypto cards

   - support for FORTIFY_SOURCE

   - addition of missing z13 and new z14 instructions to the in-kernel
     disassembler

   - generate opcode tables for the in-kernel disassembler out of a
     simple text file instead of having to manually maintain those
     tables

   - fast memset16, memset32 and memset64 implementations

   - removal of named saved segment support

   - hardware counter support for z14

   - queued spinlocks and queued rwlocks implementations for s390

   - use the stack_depth tracking feature for s390 BPF JIT

   - a new s390_sthyi system call which emulates the sthyi (store
     hypervisor information) instruction

   - removal of the old KVM virtio transport

   - an s390 specific CPU alternatives implementation which is used in
     the new spinlock code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits)
  MAINTAINERS: add virtio-ccw.h to virtio/s390 section
  s390/noexec: execute kexec datamover without DAT
  s390: fix transactional execution control register handling
  s390/bpf: take advantage of stack_depth tracking
  s390: simplify transactional execution elf hwcap handling
  s390/zcrypt: Rework struct ap_qact_ap_info.
  s390/virtio: remove unused header file kvm_virtio.h
  s390: avoid undefined behaviour
  s390/disassembler: generate opcode tables from text file
  s390/disassembler: remove insn_to_mnemonic()
  s390/dasd: avoid calling do_gettimeofday()
  s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.
  s390: remove named saved segment support
  s390/archrandom: Reconsider s390 arch random implementation
  s390/pci: do not require AIS facility
  s390/qdio: sanitize put_indicator
  s390/qdio: use atomic_cmpxchg
  s390/nmi: avoid using long-displacement facility
  s390: pass endianness info to sparse
  s390/decompressor: remove informational messages
  ...
2017-11-13 11:47:01 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Himanshu Jha 8179c7ba10 s390/sclp: Use setup_timer and mod_timer
Use setup_timer and mod_timer API instead of structure assignments.

This is done using Coccinelle and semantic patch used
for this as follows:

@@
expression x,y,z,a,b;
@@

-init_timer (&x);
+setup_timer (&x, y, z);
+mod_timer (&a, b);
-x.function = y;
-x.data = z;
-x.expires = b;
-add_timer(&a);

Signed-off-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-09-28 07:29:43 +02:00
Peter Oberparleiter 8f50af49f5 s390/console: Make preferred console handling more consistent
Use the same code structure when determining preferred consoles for
Linux running as KVM guest as with Linux running in LPAR and z/VM
guest:

 - Extend the console_mode variable to cover vt220 and hvc consoles
 - Determine sensible console defaults in conmode_default()
 - Remove KVM-special handling in set_preferred_console()

Ensure that the sclp line mode console is also registered when the
vt220 console was selected to not change existing behavior that
someone might be relying on.

As an externally visible change, KVM guest users can now select
the 3270 or 3215 console devices using the conmode= kernel parameter,
provided that support for the corresponding driver was compiled into
the kernel.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Jing Liu <liujbjl@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-13 10:58:07 +02:00
Martin Schwidefsky 25b41a7b67 s390/sclp: add parameter to specify number of buffer pages
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>
2013-06-26 21:10:03 +02:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking 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>
2010-03-30 22:02:32 +09:00
Michael Holzheu f3dfa86caa [S390] Use del_timer instead of del_timer_sync
When syncing the sclp console queue, we call del_timer_sync() while holding
the "sclp_con_lock" spinlock. This lock is also taken in the timer function
"sclp_console_timeout". Therefore the sync version of del_timer() cannot be
used here. Because the synchronous deletion of the timer is only needed
in the suspend callback and in that case only one CPU is remaining and
therefore it is not possible that the timer function is running in parallel,
we can safely use del_timer() instead of del_timer_sync().

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-22 12:08:19 +02:00
Heiko Carstens 4c8f4794b6 [S390] sclp console: convert from bootmem to slab
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>
2009-06-22 12:08:17 +02:00
Michael Holzheu 62b7494209 [S390] pm: power management support for SCLP drivers.
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>
2009-06-16 10:31:16 +02:00
Holger Smolinski 2332ce1a97 [S390] console flush on panic / reboot
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>
2008-10-10 21:34:01 +02:00
Heiko Carstens 095761d28a [S390] sclp_tty: remove ioctl interface.
After all we came to the conclusion that this interface doesn't make any
sense. Besides that the ioctl number used was never registered, the header
file isn't exported, and we doubt there is even a single user.
So remove this interface, since it eases maintenance.

Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:25 +02:00
Martin Schwidefsky a12c53f4fa [S390] Cleanup sclp printk messages.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:19 +02:00
Julia Lawall 3ca1c9907a [S390] drivers/s390: Eliminate NULL test and memset after alloc_bootmem
As noted by Akinobu Mita in patch b1fceac2b9,
alloc_bootmem and related functions never return NULL and always return a
zeroed region of memory.  Thus a NULL test or memset after calls to these
functions is unnecessary.

 drivers/s390/char/raw3270.c  |   11 +----------
 drivers/s390/char/sclp_con.c |    2 --
 2 files changed, 1 insertion(+), 12 deletions(-)

This was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression E;
statement S;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
(
- BUG_ON (E == NULL);
|
- if (E == NULL) S
)

@@
expression E,E1;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
- memset(E,0,E1);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:15 +02:00
Heiko Carstens 4d284cac76 [S390] Avoid excessive inlining.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:53 +01:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00