summaryrefslogtreecommitdiff
path: root/include/linux/pstore_ram.h
AgeCommit message (Collapse)AuthorFilesLines
2022-10-17pstore/ram: Move internal definitions out of kernel-wide includeKees Cook1-99/+0
Most of the details of the ram backend are entirely internal to the backend itself. Leave only what is needed to instantiate a ram backend in the kernel-wide header. Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-and-tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20221011200112.731334-4-keescook@chromium.org
2020-05-30pstore/ram: Introduce max_reason and convert dump_oopsKees Cook1-1/+1
Now that pstore_register() can correctly pass max_reason to the kmesg dump facility, introduce a new "max_reason" module parameter and "max-reason" Device Tree field. The "dump_oops" module parameter and "dump-oops" Device Tree field are now considered deprecated, but are now automatically converted to their corresponding max_reason values when present, though the new max_reason setting has precedence. For struct ramoops_platform_data, the "dump_oops" member is entirely replaced by a new "max_reason" member, with the only existing user updated in place. Additionally remove the "reason" filter logic from ramoops_pstore_write(), as that is not specifically needed anymore, though technically this is a change in behavior for any ramoops users also setting the printk.always_kmsg_dump boot param, which will cause ramoops to behave as if max_reason was set to KMSG_DUMP_MAX. Co-developed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Link: https://lore.kernel.org/lkml/20200515184434.8470-6-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282Thomas Gleixner1-10/+1
Based on 1 normalized pattern(s): this software is licensed under the terms of the gnu general public license version 2 as published by the free software foundation and may be copied distributed and modified under those terms this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 285 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-03pstore: Map PSTORE_TYPE_* to stringsJoel Fernandes (Google)1-0/+3
In later patches we will need to map types to names, so create a constant table for that which can also be used in different parts of old and new code. This saves the type in the PRZ which will be useful in later patches. Instead of having an explicit PSTORE_TYPE_UNKNOWN, just use ..._MAX. This includes removing the now redundant filename templates which can use a single format string. Also, there's no reason to limit the "is it still compressed?" test to only PSTORE_TYPE_DMESG when building the pstorefs filename. Records are zero-initialized, so a backend would need to have explicitly set compressed=1. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore/ram: Add kern-doc for struct persistent_ram_zoneKees Cook1-3/+43
The struct persistent_ram_zone wasn't well documented. This adds kern-doc for it. Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore: Avoid duplicate call of persistent_ram_zap()Peng Wang1-0/+1
When initialing a prz, if invalid data is found (no PERSISTENT_RAM_SIG), the function call path looks like this: ramoops_init_prz -> persistent_ram_new -> persistent_ram_post_init -> persistent_ram_zap persistent_ram_zap As we can see, persistent_ram_zap() is called twice. We can avoid this by adding an option to persistent_ram_new(), and only call persistent_ram_zap() when it is needed. Signed-off-by: Peng Wang <wangpeng15@xiaomi.com> [kees: minor tweak to exit path and commit log] Signed-off-by: Kees Cook <keescook@chromium.org>
2018-10-22pstore/ram: Clarify resource reservation labelsKees Cook1-1/+2
When ramoops reserved a memory region in the kernel, it had an unhelpful label of "persistent_memory". When reading /proc/iomem, it would be repeated many times, did not hint that it was ramoops in particular, and didn't clarify very much about what each was used for: 400000000-407ffffff : Persistent Memory (legacy) 400000000-400000fff : persistent_memory 400001000-400001fff : persistent_memory ... 4000ff000-4000fffff : persistent_memory Instead, this adds meaningful labels for how the various regions are being used: 400000000-407ffffff : Persistent Memory (legacy) 400000000-400000fff : ramoops:dump(0/252) 400001000-400001fff : ramoops:dump(1/252) ... 4000fc000-4000fcfff : ramoops:dump(252/252) 4000fd000-4000fdfff : ramoops:console 4000fe000-4000fe3ff : ramoops:ftrace(0/3) 4000fe400-4000fe7ff : ramoops:ftrace(1/3) 4000fe800-4000febff : ramoops:ftrace(2/3) 4000fec00-4000fefff : ramoops:ftrace(3/3) 4000ff000-4000fffff : ramoops:pmsg Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Tested-by: Guenter Roeck <groeck@chromium.org>
2018-03-07pstore/ram: Do not use stack VLA for parity workspaceKees Cook1-0/+1
Instead of using a stack VLA for the parity workspace, preallocate a memory region. The preallocation is done to keep from needing to perform allocations during crash dump writing, etc. This also fixes a missed release of librs on free. Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15ramoops: Split ftrace buffer space into per-CPU zonesJoel Fernandes1-0/+3
If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split the ftrace space into multiple zones depending on the number of CPUs. This speeds up the performance of function tracing by about 280% in my tests as we avoid the locking. The trade off being lesser space available per CPU. Let the ramoops user decide which option they want based on pdata flag. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: added max_ftrace_cnt to track size, added DT logic and docs] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Allow prz to control need for lockingJoel Fernandes1-1/+9
In preparation of not locking at all for certain buffers depending on if there's contention, make locking optional depending on the initialization of the prz. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: moved locking flag into prz instead of via caller arguments] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-11pstore: Make spinlock per zone instead of globalJoel Fernandes1-0/+1
Currently pstore has a global spinlock for all zones. Since the zones are independent and modify different areas of memory, there's no need to have a global lock, so we should use a per-zone lock as introduced here. Also, when ramoops's ftrace use-case has a FTRACE_PER_CPU flag introduced later, which splits the ftrace memory area into a single zone per CPU, it will eliminate the need for locking. In preparation for this, make the locking optional. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: updated commit message] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-09-08pstore/pmsg: drop bounce bufferMark Salyzyn1-2/+5
Removing a bounce buffer copy operation in the pmsg driver path is always better. We also gain in overall performance by not requesting a vmalloc on every write as this can cause precious RT tasks, such as user facing media operation, to stall while memory is being reclaimed. Added a write_buf_user to the pstore functions, a backup platform write_buf_user that uses the small buffer that is part of the instance, and implemented a ramoops write_buf_user that only supports PSTORE_TYPE_PMSG. Signed-off-by: Mark Salyzyn <salyzyn@android.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2016-03-10pstore: Add support for 64 Bit address spaceWiebe, Wladislav (Nokia - DE/Ulm)1-1/+1
Some architectures have their reserved RAM in 64 Bit address space. Therefore convert mem_address module parameter to ullong. Signed-off-by: Wladislav Wiebe <wladislav.wiebe@nokia.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-01-16pstore: Add pmsg - user-space accessible pstore objectMark Salyzyn1-0/+1
A secured user-space accessible pstore object. Writes to /dev/pmsg0 are appended to the buffer, on reboot the persistent contents are available in /sys/fs/pstore/pmsg-ramoops-[ID]. One possible use is syslogd, or other daemon, can write messages, then on reboot provides a means to triage user-space activities leading up to a panic as a companion to the pstore dmesg or console logs. Signed-off-by: Mark Salyzyn <salyzyn@android.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-12-11pstore-ram: Allow optional mapping with pgprot_noncachedTony Lindgren1-1/+3
On some ARMs the memory can be mapped pgprot_noncached() and still be working for atomic operations. As pointed out by Colin Cross <ccross@android.com>, in some cases you do want to use pgprot_noncached() if the SoC supports it to see a debug printk just before a write hanging the system. On ARMs, the atomic operations on strongly ordered memory are implementation defined. So let's provide an optional kernel parameter for configuring pgprot_noncached(), and use pgprot_writecombine() by default. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robherring2@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Olof Johansson <olof@lixom.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: stable@vger.kernel.org Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-04-03pstore/ram: Allow specifying ecc parameters in platform dataArve Hjønnevåg1-4/+10
Allow specifying ecc parameters in platform data Signed-off-by: Arve Hjønnevåg <arve@android.com> [jstultz: Tweaked commit subject & add commit message] Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Anton Vorontsov <anton@enomsg.org>
2013-01-03pstore: remove __dev* attributes.Greg Kroah-Hartman1-3/+2
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit from the pstore filesystem. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Anton Vorontsov <cbouatmailru@gmail.com> Cc: Colin Cross <ccross@android.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17pstore/ram: Make tracing log versionedAnton Vorontsov1-1/+1
Decoding the binary trace w/ a different kernel might be troublesome since we convert addresses to symbols. For kernels with minimal changes, the mappings would probably match, but it's not guaranteed at all. (But still we could convert the addresses by hand, since we do print raw addresses.) If we use modules, the symbols could be loaded at different addresses from the previously booted kernel, and so this would also fail, but there's nothing we can do about it. Also, the binary data format that pstore/ram is using in its ringbuffer may change between the kernels, so here we too must ensure that we're running the same kernel. So, there are two questions really: 1. How to compute the unique kernel tag; 2. Where to store it. In this patch we're using LINUX_VERSION_CODE, just as hibernation (suspend-to-disk) does. This way we are protecting from the kernel version mismatch, making sure that we're running the same kernel version and patch level. We could use CRC of a symbol table (as suggested by Tony Luck), but for now let's not be that strict. And as for storing, we are using a small trick here. Instead of allocating a dedicated buffer for the tag (i.e. another prz), or hacking ram_core routines to "reserve" some control data in the buffer, we are just encoding the tag into the buffer signature (and XOR'ing it with the actual signature value, so that buffers not needing a tag can just pass zero, which will result into the plain old PRZ signature). Suggested-by: Steven Rostedt <rostedt@goodmis.org> Suggested-by: Tony Luck <tony.luck@intel.com> Suggested-by: Colin Cross <ccross@android.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17pstore: Headers should include all stuff they useAnton Vorontsov1-0/+1
Headers should really include all the needed prototypes, types, defines etc. to be self-contained. This is a long-standing issue, but apparently the new tracing code unearthed it (SMP=n is also a prerequisite): In file included from fs/pstore/internal.h:4:0, from fs/pstore/ftrace.c:21: include/linux/pstore.h:43:15: error: field ‘read_mutex’ has incomplete type While at it, I also added the following: linux/types.h -> size_t, phys_addr_t, uXX and friends linux/spinlock.h -> spinlock_t linux/errno.h -> Exxxx linux/time.h -> struct timespec (struct passed by value) struct module and rs_control forward declaration (passed via pointers). Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17pstore/ram: Add ftrace messages handlingAnton Vorontsov1-0/+1
The ftrace log size is configurable via ramoops.ftrace_size module option, and the log itself is available via <pstore-mount>/ftrace-ramoops file. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17pstore/ram_core: Get rid of prz->ecc enable/disable flagAnton Vorontsov1-1/+0
Nowadays we can use prz->ecc_size as a flag, no need for the special member in the prz struct. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17pstore/ram: Make ECC size configurableAnton Vorontsov1-2/+2
This is now pretty straightforward: instead of using bool, just pass an integer. For backwards compatibility ramoops.ecc=1 means 16 bytes ECC (using 1 byte for ECC isn't much of use anyway). Suggested-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17pstore/ram_core: Get rid of prz->ecc_symsize and prz->ecc_polyAnton Vorontsov1-2/+0
The struct members were never used anywhere outside of persistent_ram_init_ecc(), so there's actually no need for them to be in the struct. If we ever want to make polynomial or symbol size configurable, it would make more sense to just pass initialized rs_decoder to the persistent_ram init functions. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-20pstore/ram: Probe as early as possibleAnton Vorontsov1-3/+3
Registering the platform driver before module_init allows us to log oopses that happen during device probing. This requires changing module_init to postcore_initcall, and switching from platform_driver_probe to platform_driver_register because the platform device is not registered when the platform driver is registered; and because we use driver_register, now can't use create_bundle() (since it will try to register the same driver once again), so we have to switch to platform_device_register_data(). Also, some __init -> __devinit changes were needed. Overall, the registration logic is now much clearer, since we have only one driver registration point, and just an optional dummy device, which is created from the module parameters. Suggested-by: Colin Cross <ccross@android.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13pstore/ram_core: Remove now unused codeAnton Vorontsov1-19/+0
The code tried to maintain the global list of persistent ram zones, which isn't a great idea overall, plus since Android's ram_console is no longer there, we can remove some unused functions. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Colin Cross <ccross@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13pstore/ram: Add console messages handlingAnton Vorontsov1-0/+1
The console log size is configurable via ramoops.console_size module option, and the log itself is available via <pstore-mount>/console-ramoops file. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13pstore/ram_core: Factor persistent_ram_zap() out of post_init()Anton Vorontsov1-0/+1
A handy function that we will use outside of ram_core soon. But so far just factor it out and start using it in post_init(). Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13pstore/ram: Should update old dmesg buffer before readingAnton Vorontsov1-0/+1
Without the update, we'll only see the new dmesg buffer after the reboot, but previously we could see it right away. Making an oops visible in pstore filesystem before reboot is a somewhat dubious feature, but removing it wasn't an intentional change, so let's restore it. For this we have to make persistent_ram_save_old() safe for calling multiple times, and also extern it. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-17pstore/ram: Add ECC supportAnton Vorontsov1-0/+1
This is now straightforward: just introduce a module parameter and pass the needed value to persistent_ram_new(). Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Marco Stornelli <marco.stornelli@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-17staging: android: persistent_ram: Move to fs/pstore/ram_core.cAnton Vorontsov1-0/+80
This is a first step for adding ECC support for pstore RAM backend: we will use the persistent_ram routines, kindly provided by Google. Basically, persistent_ram is a set of helper routines to deal with the [optionally] ECC-protected persistent ram regions. A bit of Makefile, Kconfig and header files adjustments were needed because of the move. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-16ramoops: Move to fs/pstore/ram.cAnton Vorontsov1-0/+17
Since ramoops was converted to pstore, it has nothing to do with character devices nowadays. Instead, today it is just a RAM backend for pstore. The patch just moves things around. There are a few changes were needed because of the move: 1. Kconfig and Makefiles fixups, of course. 2. In pstore/ram.c we have to play a bit with MODULE_PARAM_PREFIX, this is needed to keep user experience the same as with ramoops driver (i.e. so that ramoops.foo kernel command line arguments would still work). Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Marco Stornelli <marco.stornelli@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>