Commit Graph

18 Commits

Author SHA1 Message Date
Alexander Egorenkov
20e6ce4818 watchdog: diag288_wdt: unify lpar and zvm diag288 helpers
Change naming of the internal diag288 helper functions
to improve overall readability and reduce confusion:
* Rename __diag288() to diag288().
* Get rid of the misnamed helper __diag288_lpar() that was used not only
  on LPARs but also zVM and KVM systems.
* Rename __diag288_vm() to diag288_str().

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230203073958.1585738-6-egorenar@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06 15:14:10 +01:00
Alexander Egorenkov
3790085198 watchdog: diag288_wdt: de-duplicate diag_stat_inc() calls
Call diag_stat_inc() from __diag288() to reduce code duplication.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230203073958.1585738-5-egorenar@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06 15:14:09 +01:00
Alexander Egorenkov
221f748ac8 watchdog: diag288_wdt: unify command buffer handling for diag288 zvm
Simplify and de-duplicate code by introducing a common single command
buffer allocated once at initialization. Moreover, simplify the interface
of __diag288_vm() by accepting ASCII strings as the command parameter
and converting it to the EBCDIC format within the function itself.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230203073958.1585738-4-egorenar@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06 15:14:09 +01:00
Alexander Egorenkov
f102dd16eb watchdog: diag288_wdt: remove power management
Remove power management because s390 no longer supports hibernation since
commit 394216275c ("s390: remove broken hibernate / power management
support").

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230203073958.1585738-3-egorenar@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06 15:14:08 +01:00
Alexander Egorenkov
c24def73a2 watchdog: diag288_wdt: get rid of register asm
Using register asm statements has been proven to be very error prone,
especially when using code instrumentation where gcc may add function
calls, which clobbers register contents in an unexpected way.

Therefore, get rid of register asm statements in watchdog code, and make
sure this bug class cannot happen.

Moreover, remove the register r1 from the clobber list because this
register is not changed by DIAG 288.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230203073958.1585738-2-egorenar@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06 15:14:08 +01:00
Alexander Egorenkov
32e40f9506 watchdog: diag288_wdt: fix __diag288() inline assembly
The DIAG 288 statement consumes an EBCDIC string the address of which is
passed in a register. Use a "memory" clobber to tell the compiler that
memory is accessed within the inline assembly.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-30 14:40:50 +01:00
Alexander Egorenkov
fe8973a3ad watchdog: diag288_wdt: do not use stack buffers for hardware data
With CONFIG_VMAP_STACK=y the stack is allocated from the vmalloc space.
Data passed to a hardware or a hypervisor interface that
requires V=R can no longer be allocated on the stack.

Use kmalloc() to get memory for a diag288 command.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-30 14:40:50 +01:00
Junlin Yang
266b2e335c watchdog: diag288_wdt: Remove redundant assignment
The assign for 'ret' is redundant and can be removed,
because it will be assigned before use.

Signed-off-by: Junlin Yang <yangjunlin@yulong.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210203122404.752-1-angkery@163.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2021-06-21 08:49:14 +02:00
Guenter Roeck
31bfa64e94 watchdog: diag288_wdt: Remove leftover includes from conversion to watchdog API
Commit f7a94db4e9 ("s390/watchdog: use watchdog API") converted
the driver to use the watchdog API, but some includes as well as
MODULE_ALIAS_MISCDEV() were missed.

Cc: Philipp Hachtmann <phacht@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-09-17 08:59:01 +02:00
Thomas Gleixner
09c434b8a0 treewide: Add SPDX license identifier for more missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Julia Lawall
323edb2e27 watchdog: constify watchdog_ops and watchdog_info structures
These watchdog_ops and watchdog_info structures are only stored
in the ops and info fields of a watchdog_device structure,
respectively, which are const.  Thus make the watchdog_ops and
watchdog_info structures const as well.

Done with the help of Coccinelle.  The rules for the watchdog_ops case are
as follows:

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct watchdog_ops i@p = { ... };

@ok@
identifier r.i;
struct watchdog_device e;
position p;
@@
e.ops = &i@p;

@bad@
position p != {r.p,ok.p};
identifier r.i;
struct watchdog_ops e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct watchdog_ops i = { ... };
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-09-09 20:29:53 +02:00
Bhumika Goyal
b893e344bf watchdog: constify watchdog_ops structures
Declare watchdog_ops structures as const as they are only stored in the
ops field of a watchdog_device structure. This field is of type const, so
watchdog_ops structures having this property can be made const too.
Done using Coccinelle:

@r disable optional_qualifier@
identifier x;
position p;
@@
static struct watchdog_ops x@p={...};

@ok@
struct watchdog_device w;
identifier r.x;
position p;
@@
w.ops=&x@p;

@bad@
position p != {r.p,ok.p};
identifier r.x;
@@
x@p

@depends on !bad disable optional_qualifier@
identifier r.x;
@@
+const
struct watchdog_ops x;

File size details before and after patching.
First line of every .o file shows the file size before patching
and second line shows the size after patching.

   text    data     bss     dec     hex filename

   1340	    544	      0	   1884	    75c	drivers/watchdog/bcm_kona_wdt.o
   1436	    440	      0	   1876	    754	drivers/watchdog/bcm_kona_wdt.o

   1176	    544	      4	   1724	    6bc	drivers/watchdog/digicolor_wdt.o
   1272	    440	      4	   1716	    6b4	drivers/watchdog/digicolor_wdt.o

    925	    580	     89	   1594	    63a	drivers/watchdog/ep93xx_wdt.o
   1021	    476	     89	   1586	    632	drivers/watchdog/ep93xx_wdt.o

   4932	    288	     17	   5237	   1475	drivers/watchdog/s3c2410_wdt.o
   5028	    192	     17	   5237	   1475	drivers/watchdog/s3c2410_wdt.o

   1977	    292	      1	   2270	    8de	drivers/watchdog/sama5d4_wdt.o
   2073	    196	      1	   2270	    8de	drivers/watchdog/sama5d4_wdt.o

   1375	    484	      1	   1860	    744	drivers/watchdog/sirfsoc_wdt.o
   1471	    380	      1	   1852	    73c	drivers/watchdog/sirfsoc_wdt.o

Size remains the same for the files drivers/watchdog/diag288_wdt.o
drivers/watchdog/asm9260_wdt.o and drivers/watchdog/atlas7_wdt.o

The following .o files did not compile:
drivers/watchdog/sun4v_wdt.o, drivers/watchdog/sbsa_gwdt.o,
drivers/watchdog/rt2880_wdt.o, drivers/watchdog/booke_wdt.o
drivers/watchdog/mt7621_wdt.o

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-02-24 14:00:23 -08:00
Guenter Roeck
e7d162faa6 watchdog: diag288: Stop re-using watchdog core internal flags
A watchdog driver should not use watchdog subsystem internal flags.
Use a driver variable and flag instead to maintain the watchdog state
and to determine if a suspend operation is possible or not.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-29 20:36:02 +01:00
Martin Schwidefsky
1ec2772e0c s390/diag: add a statistic for diagnose calls
Introduce /sys/debug/kernel/diag_stat with a statistic how many diagnose
calls have been done by each CPU in the system.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:06 +02:00
Xu Wang
b2527d2009 s390/watchdog: support for KVM hypervisors and delete pr_info messages
This patch extends the diag288 watchdog driver to be able to deal with KVM
hypervisors. Only z/VM needs special handling, we can use the same interface
as on LPAR. Remove all pr_info output to avoid misconception. Because there
is no value in these messages and only the pr_err messages make sense.

Signed-off-by: Xu Wang <gesaint@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25 11:49:42 +01:00
Xu Wang
9ec6cb80c8 s390/watchdog: enable KEEPALIVE for /dev/watchdog
There's no reason why we wouldn't want to be able to send a keep alive
message to /dev/watchdog (feed dog) for the s390 diag288 watchdog, so
let's enable the WDIOF_KEEPALIVEPING option.

Signed-off-by: Xu Wang <gesaint@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25 11:49:41 +01:00
Philipp Hachtmann
646f919e93 s390/watchdog: add support for LPAR operation (diag288)
Add the LPAR variant of the diag 288 watchdog to the driver.
The only available action on timeout for LPAR is a PSW restart.

Signed-off-by: Philipp Hachtmann <phacht@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-06-10 10:48:29 +02:00
Philipp Hachtmann
f7a94db4e9 s390/watchdog: use watchdog API
Converted the vmwatchdog driver to use the kernel's watchdog API.

Signed-off-by: Philipp Hachtmann <phacht@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-06-10 10:48:29 +02:00