diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/debugfs-pktcdvd | 20 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-pktcdvd | 72 | ||||
| -rw-r--r-- | Documentation/cdrom/packet-writing.txt | 35 | ||||
| -rw-r--r-- | Documentation/fault-injection/failcmd.sh | 4 | ||||
| -rw-r--r-- | Documentation/fault-injection/failmodule.sh | 31 | ||||
| -rw-r--r-- | Documentation/fault-injection/fault-injection.txt | 225 | ||||
| -rw-r--r-- | Documentation/ioctl-number.txt | 2 | ||||
| -rw-r--r-- | Documentation/kernel-parameters.txt | 7 |
8 files changed, 396 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/debugfs-pktcdvd b/Documentation/ABI/testing/debugfs-pktcdvd new file mode 100644 index 000000000000..03dbd883cc41 --- /dev/null +++ b/Documentation/ABI/testing/debugfs-pktcdvd @@ -0,0 +1,20 @@ +What: /debug/pktcdvd/pktcdvd[0-7] +Date: Oct. 2006 +KernelVersion: 2.6.19 +Contact: Thomas Maier <balagi@justmail.de> +Description: + +debugfs interface +----------------- + +The pktcdvd module (packet writing driver) creates +these files in debugfs: + +/debug/pktcdvd/pktcdvd[0-7]/ + info (0444) Lots of human readable driver + statistics and infos. Multiple lines! + +Example: +------- + +cat /debug/pktcdvd/pktcdvd0/info diff --git a/Documentation/ABI/testing/sysfs-class-pktcdvd b/Documentation/ABI/testing/sysfs-class-pktcdvd new file mode 100644 index 000000000000..c4c55edc9a5c --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-pktcdvd @@ -0,0 +1,72 @@ +What: /sys/class/pktcdvd/ +Date: Oct. 2006 +KernelVersion: 2.6.19 +Contact: Thomas Maier <balagi@justmail.de> +Description: + +sysfs interface +--------------- + +The pktcdvd module (packet writing driver) creates +these files in the sysfs: +(<devid> is in format major:minor ) + +/sys/class/pktcdvd/ + add (0200) Write a block device id (major:minor) + to create a new pktcdvd device and map + it to the block device. + + remove (0200) Write the pktcdvd device id (major:minor) + to it to remove the pktcdvd device. + + device_map (0444) Shows the device mapping in format: + pktcdvd[0-7] <pktdevid> <blkdevid> + +/sys/class/pktcdvd/pktcdvd[0-7]/ + dev (0444) Device id + uevent (0200) To send an uevent. + +/sys/class/pktcdvd/pktcdvd[0-7]/stat/ + packets_started (0444) Number of started packets. + packets_finished (0444) Number of finished packets. + + kb_written (0444) kBytes written. + kb_read (0444) kBytes read. + kb_read_gather (0444) kBytes read to fill write packets. + + reset (0200) Write any value to it to reset + pktcdvd device statistic values, like + bytes read/written. + +/sys/class/pktcdvd/pktcdvd[0-7]/write_queue/ + size (0444) Contains the size of the bio write + queue. + + congestion_off (0644) If bio write queue size is below + this mark, accept new bio requests + from the block layer. + + congestion_on (0644) If bio write queue size is higher + as this mark, do no longer accept + bio write requests from the block + layer and wait till the pktcdvd + device has processed enough bio's + so that bio write queue size is + below congestion off mark. + A value of <= 0 disables congestion + control. + + +Example: +-------- +To use the pktcdvd sysfs interface directly, you can do: + +# create a new pktcdvd device mapped to /dev/hdc +echo "22:0" >/sys/class/pktcdvd/add +cat /sys/class/pktcdvd/device_map +# assuming device pktcdvd0 was created, look at stat's +cat /sys/class/pktcdvd/pktcdvd0/stat/kb_written +# print the device id of the mapped block device +fgrep pktcdvd0 /sys/class/pktcdvd/device_map +# remove device, using pktcdvd0 device id 253:0 +echo "253:0" >/sys/class/pktcdvd/remove diff --git a/Documentation/cdrom/packet-writing.txt b/Documentation/cdrom/packet-writing.txt index 3d44c561fe6d..7715d2247c4d 100644 --- a/Documentation/cdrom/packet-writing.txt +++ b/Documentation/cdrom/packet-writing.txt @@ -90,6 +90,41 @@ Notes to create an ext2 filesystem on the disc. +Using the pktcdvd sysfs interface +--------------------------------- + +Since Linux 2.6.19, the pktcdvd module has a sysfs interface +and can be controlled by it. For example the "pktcdvd" tool uses +this interface. (see http://people.freenet.de/BalaGi#pktcdvd ) + +"pktcdvd" works similar to "pktsetup", e.g.: + + # pktcdvd -a dev_name /dev/hdc + # mkudffs /dev/pktcdvd/dev_name + # mount -t udf -o rw,noatime /dev/pktcdvd/dev_name /dvdram + # cp files /dvdram + # umount /dvdram + # pktcdvd -r dev_name + + +For a description of the sysfs interface look into the file: + + Documentation/ABI/testing/sysfs-block-pktcdvd + + +Using the pktcdvd debugfs interface +----------------------------------- + +To read pktcdvd device infos in human readable form, do: + + # cat /debug/pktcdvd/pktcdvd[0-7]/info + +For a description of the debugfs interface look into the file: + + Documentation/ABI/testing/debugfs-pktcdvd + + + Links ----- diff --git a/Documentation/fault-injection/failcmd.sh b/Documentation/fault-injection/failcmd.sh new file mode 100644 index 000000000000..63177aba8106 --- /dev/null +++ b/Documentation/fault-injection/failcmd.sh @@ -0,0 +1,4 @@ +#!/bin/bash + +echo 1 > /proc/self/make-it-fail +exec $* diff --git a/Documentation/fault-injection/failmodule.sh b/Documentation/fault-injection/failmodule.sh new file mode 100644 index 000000000000..474a8b971f9c --- /dev/null +++ b/Documentation/fault-injection/failmodule.sh @@ -0,0 +1,31 @@ +#!/bin/bash +# +# Usage: failmodule <failname> <modulename> [stacktrace-depth] +# +# <failname>: "failslab", "fail_alloc_page", or "fail_make_request" +# +# <modulename>: module name that you want to inject faults. +# +# [stacktrace-depth]: the maximum number of stacktrace walking allowed +# + +STACKTRACE_DEPTH=5 +if [ $# -gt 2 ]; then + STACKTRACE_DEPTH=$3 +fi + +if [ ! -d /debug/$1 ]; then + echo "Fault-injection $1 does not exist" >&2 + exit 1 +fi +if [ ! -d /sys/module/$2 ]; then + echo "Module $2 does not exist" >&2 + exit 1 +fi + +# Disable any fault injection +echo 0 > /debug/$1/stacktrace-depth + +echo `cat /sys/module/$2/sections/.text` > /debug/$1/require-start +echo `cat /sys/module/$2/sections/.exit.text` > /debug/$1/require-end +echo $STACKTRACE_DEPTH > /debug/$1/stacktrace-depth diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt new file mode 100644 index 000000000000..b7ca560b9340 --- /dev/null +++ b/Documentation/fault-injection/fault-injection.txt @@ -0,0 +1,225 @@ +Fault injection capabilities infrastructure +=========================================== + +See also drivers/md/faulty.c and "every_nth" module option for scsi_debug. + + +Available fault injection capabilities +-------------------------------------- + +o failslab + + injects slab allocation failures. (kmalloc(), kmem_cache_alloc(), ...) + +o fail_page_alloc + + injects page allocation failures. (alloc_pages(), get_free_pages(), ...) + +o fail_make_request + + injects disk IO errors on devices permitted by setting + /sys/block/<device>/make-it-fail or + /sys/block/<device>/<partition>/make-it-fail. (generic_make_request()) + +Configure fault-injection capabilities behavior +----------------------------------------------- + +o debugfs entries + +fault-inject-debugfs kernel module provides some debugfs entries for runtime +configuration of fault-injection capabilities. + +- /debug/fail*/probability: + + likelihood of failure injection, in percent. + Format: <percent> + + Note that one-failure-per-hundred is a very high error rate + for some testcases. Consider setting probability=100 and configure + /debug/fail*/interval for such testcases. + +- /debug/fail*/interval: + + specifies the interval between failures, for calls to + should_fail() that pass all the other tests. + + Note that if you enable this, by setting interval>1, you will + probably want to set probability=100. + +- /debug/fail*/times: + + specifies how many times failures may happen at most. + A value of -1 means "no limit". + +- /debug/fail*/space: + + specifies an initial resource "budget", decremented by "size" + on each call to should_fail(,size). Failure injection is + suppressed until "space" reaches zero. + +- /debug/fail*/verbose + + Format: { 0 | 1 | 2 } + specifies the verbosity of the messages when failure is + injected. '0' means no messages; '1' will print only a single + log line per failure; '2' will print a call trace too -- useful + to debug the problems revealed by fault injection. + +- /debug/fail*/task-filter: + + Format: { 'Y' | 'N' } + A value of 'N' disables filtering by process (default). + Any positive value limits failures to only processes indicated by + /proc/<pid>/make-it-fail==1. + +- /debug/fail*/require-start: +- /debug/fail*/require-end: +- /debug/fail*/reject-start: +- /debug/fail*/reject-end: + + specifies the range of virtual addresses tested during + stacktrace walking. Failure is injected only if some caller + in the walked stacktrace lies within the required range, and + none lies within the rejected range. + Default required range is [0,ULONG_MAX) (whole of virtual address space). + Default rejected range is [0,0). + +- /debug/fail*/stacktrace-depth: + + specifies the maximum stacktrace depth walked during search + for a caller within [require-start,require-end) OR + [reject-start,reject-end). + +- /debug/fail_page_alloc/ignore-gfp-highmem: + + Format: { 'Y' | 'N' } + default is 'N', setting it to 'Y' won't inject failures into + highmem/user allocations. + +- /debug/failslab/ignore-gfp-wait: +- /debug/fail_page_alloc/ignore-gfp-wait: + + Format: { 'Y' | 'N' } + default is 'N', setting it to 'Y' will inject failures + only into non-sleep allocations (GFP_ATOMIC allocations). + +o Boot option + +In order to inject faults while debugfs is not available (early boot time), +use the boot option: + + failslab= + fail_page_alloc= + fail_make_request=<interval>,<probability>,<space>,<times> + +How to add new fault injection capability +----------------------------------------- + +o #include <linux/fault-inject.h> + +o define the fault attributes + + DECLARE_FAULT_INJECTION(name); + + Please see the definition of struct fault_attr in fault-inject.h + for details. + +o provide a way to configure fault attributes + +- boot option + + If you need to enable the fault injection capability from boot time, you can + provide boot option to configure it. There is a helper function for it: + + setup_fault_attr(attr, str); + +- debugfs entries + + failslab, fail_page_alloc, and fail_make_request use this way. + Helper functions: + + init_fault_attr_entries(entries, attr, name); + void cleanup_fault_attr_entries(entries); + +- module parameters + + If the scope of the fault injection capability is limited to a + single kernel module, it is better to provide module parameters to + configure the fault attributes. + +o add a hook to insert failures + + Upon should_fail() returning true, client code should inject a failure. + + should_fail(attr, size); + +Application Examples +-------------------- + +o inject slab allocation failures into module init/cleanup code + +------------------------------------------------------------------------------ +#!/bin/bash + +FAILCMD=Documentation/fault-injection/failcmd.sh +BLACKLIST="root_plug evbug" + +FAILNAME=failslab +echo Y > /debug/$FAILNAME/task-filter +echo 10 > /debug/$FAILNAME/probability +echo 100 > /debug/$FAILNAME/interval +echo -1 > /debug/$FAILNAME/times +echo 2 > /debug/$FAILNAME/verbose +echo 1 > /debug/$FAILNAME/ignore-gfp-wait + +blacklist() +{ + echo $BLACKLIST | grep $1 > /dev/null 2>&1 +} + +oops() +{ + dmesg | grep BUG > /dev/null 2>&1 +} + +find /lib/modules/`uname -r` -name '*.ko' -exec basename {} .ko \; | + while read i + do + oops && exit 1 + + if ! blacklist $i + then + echo inserting $i... + bash $FAILCMD modprobe $i + fi + done + +lsmod | awk '{ if ($3 == 0) { print $1 } }' | + while read i + do + oops && exit 1 + + if ! blacklist $i + then + echo removing $i... + bash $FAILCMD modprobe -r $i + fi + done + +------------------------------------------------------------------------------ + +o inject slab allocation failures only for a specific module + +------------------------------------------------------------------------------ +#!/bin/bash + +FAILMOD=Documentation/fault-injection/failmodule.sh + +echo injecting errors into the module $1... + +modprobe $1 +bash $FAILMOD failslab $1 10 +echo 25 > /debug/failslab/probability + +------------------------------------------------------------------------------ + diff --git a/Documentation/ioctl-number.txt b/Documentation/ioctl-number.txt index edc04d74ae23..5a8bd5bd88ef 100644 --- a/Documentation/ioctl-number.txt +++ b/Documentation/ioctl-number.txt @@ -191,3 +191,5 @@ Code Seq# Include File Comments <mailto:aherrman@de.ibm.com> 0xF3 00-3F video/sisfb.h sisfb (in development) <mailto:thomas@winischhofer.net> +0xF4 00-1F video/mbxfb.h mbxfb + <mailto:raph@8d.com> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index b79bcdf16319..d8323b8893c3 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -548,6 +548,13 @@ and is between 256 and 4096 characters. It is defined in the file eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog. Format: <io>[,<irq>] + failslab= + fail_page_alloc= + fail_make_request=[KNL] + General fault injection mechanism. + Format: <interval>,<probability>,<space>,<times> + See also /Documentation/fault-injection/. + fd_mcs= [HW,SCSI] See header of drivers/scsi/fd_mcs.c. |