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![Jiri Bohac](/assets/img/avatar_default.png)
Both pstore_compress() and decompress_record() use a mistyped config
option name ("PSTORE_COMPRESSION" instead of "PSTORE_COMPRESS"). As
a result compression and decompression of pstore records was always
disabled.
Use the correct config option name.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Fixes: fd49e03280
("pstore: Fix linking when crypto API disabled")
Acked-by: Matteo Croce <mcroce@microsoft.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210218111547.johvp5klpv3xrpnn@dwarf.suse.cz
847 lines
19 KiB
C
847 lines
19 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Persistent Storage - platform driver interface parts.
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*
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* Copyright (C) 2007-2008 Google, Inc.
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* Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
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*/
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#define pr_fmt(fmt) "pstore: " fmt
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#include <linux/atomic.h>
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/kmsg_dump.h>
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#include <linux/console.h>
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#include <linux/module.h>
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#include <linux/pstore.h>
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#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
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#include <linux/lzo.h>
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
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#include <linux/lz4.h>
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
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#include <linux/zstd.h>
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#endif
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#include <linux/crypto.h>
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#include <linux/string.h>
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#include <linux/timer.h>
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include <linux/jiffies.h>
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#include <linux/workqueue.h>
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#include "internal.h"
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/*
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* We defer making "oops" entries appear in pstore - see
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* whether the system is actually still running well enough
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* to let someone see the entry
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*/
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static int pstore_update_ms = -1;
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module_param_named(update_ms, pstore_update_ms, int, 0600);
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MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content "
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"(default is -1, which means runtime updates are disabled; "
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"enabling this option may not be safe; it may lead to further "
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"corruption on Oopses)");
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/* Names should be in the same order as the enum pstore_type_id */
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static const char * const pstore_type_names[] = {
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"dmesg",
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"mce",
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"console",
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"ftrace",
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"rtas",
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"powerpc-ofw",
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"powerpc-common",
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"pmsg",
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"powerpc-opal",
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};
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static int pstore_new_entry;
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static void pstore_timefunc(struct timer_list *);
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static DEFINE_TIMER(pstore_timer, pstore_timefunc);
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static void pstore_dowork(struct work_struct *);
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static DECLARE_WORK(pstore_work, pstore_dowork);
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/*
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* psinfo_lock protects "psinfo" during calls to
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* pstore_register(), pstore_unregister(), and
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* the filesystem mount/unmount routines.
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*/
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static DEFINE_MUTEX(psinfo_lock);
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struct pstore_info *psinfo;
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static char *backend;
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module_param(backend, charp, 0444);
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MODULE_PARM_DESC(backend, "specific backend to use");
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static char *compress =
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#ifdef CONFIG_PSTORE_COMPRESS_DEFAULT
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CONFIG_PSTORE_COMPRESS_DEFAULT;
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#else
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NULL;
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#endif
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module_param(compress, charp, 0444);
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MODULE_PARM_DESC(compress, "compression to use");
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/* Compression parameters */
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static struct crypto_comp *tfm;
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struct pstore_zbackend {
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int (*zbufsize)(size_t size);
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const char *name;
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};
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static char *big_oops_buf;
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static size_t big_oops_buf_sz;
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/* How much of the console log to snapshot */
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unsigned long kmsg_bytes = CONFIG_PSTORE_DEFAULT_KMSG_BYTES;
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void pstore_set_kmsg_bytes(int bytes)
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{
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kmsg_bytes = bytes;
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}
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/* Tag each group of saved records with a sequence number */
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static int oopscount;
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const char *pstore_type_to_name(enum pstore_type_id type)
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{
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BUILD_BUG_ON(ARRAY_SIZE(pstore_type_names) != PSTORE_TYPE_MAX);
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if (WARN_ON_ONCE(type >= PSTORE_TYPE_MAX))
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return "unknown";
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return pstore_type_names[type];
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}
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EXPORT_SYMBOL_GPL(pstore_type_to_name);
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enum pstore_type_id pstore_name_to_type(const char *name)
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{
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int i;
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for (i = 0; i < PSTORE_TYPE_MAX; i++) {
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if (!strcmp(pstore_type_names[i], name))
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return i;
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}
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return PSTORE_TYPE_MAX;
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}
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EXPORT_SYMBOL_GPL(pstore_name_to_type);
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static void pstore_timer_kick(void)
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{
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if (pstore_update_ms < 0)
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return;
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mod_timer(&pstore_timer, jiffies + msecs_to_jiffies(pstore_update_ms));
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}
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/*
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* Should pstore_dump() wait for a concurrent pstore_dump()? If
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* not, the current pstore_dump() will report a failure to dump
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* and return.
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*/
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static bool pstore_cannot_wait(enum kmsg_dump_reason reason)
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{
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/* In NMI path, pstore shouldn't block regardless of reason. */
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if (in_nmi())
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return true;
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switch (reason) {
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/* In panic case, other cpus are stopped by smp_send_stop(). */
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case KMSG_DUMP_PANIC:
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/* Emergency restart shouldn't be blocked. */
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case KMSG_DUMP_EMERG:
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return true;
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default:
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return false;
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}
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}
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#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
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static int zbufsize_deflate(size_t size)
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{
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size_t cmpr;
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switch (size) {
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/* buffer range for efivars */
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case 1000 ... 2000:
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cmpr = 56;
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break;
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case 2001 ... 3000:
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cmpr = 54;
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break;
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case 3001 ... 3999:
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cmpr = 52;
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break;
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/* buffer range for nvram, erst */
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case 4000 ... 10000:
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cmpr = 45;
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break;
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default:
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cmpr = 60;
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break;
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}
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return (size * 100) / cmpr;
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}
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
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static int zbufsize_lzo(size_t size)
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{
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return lzo1x_worst_compress(size);
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}
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
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static int zbufsize_lz4(size_t size)
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{
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return LZ4_compressBound(size);
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}
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS)
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static int zbufsize_842(size_t size)
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{
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return size;
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}
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
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static int zbufsize_zstd(size_t size)
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{
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return ZSTD_compressBound(size);
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}
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#endif
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static const struct pstore_zbackend *zbackend __ro_after_init;
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static const struct pstore_zbackend zbackends[] = {
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#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
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{
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.zbufsize = zbufsize_deflate,
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.name = "deflate",
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},
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
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{
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.zbufsize = zbufsize_lzo,
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.name = "lzo",
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},
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS)
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{
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.zbufsize = zbufsize_lz4,
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.name = "lz4",
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},
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
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{
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.zbufsize = zbufsize_lz4,
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.name = "lz4hc",
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},
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS)
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{
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.zbufsize = zbufsize_842,
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.name = "842",
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},
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#endif
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#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
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{
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.zbufsize = zbufsize_zstd,
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.name = "zstd",
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},
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#endif
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{ }
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};
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static int pstore_compress(const void *in, void *out,
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unsigned int inlen, unsigned int outlen)
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{
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int ret;
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if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS))
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return -EINVAL;
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ret = crypto_comp_compress(tfm, in, inlen, out, &outlen);
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if (ret) {
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pr_err("crypto_comp_compress failed, ret = %d!\n", ret);
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return ret;
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}
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return outlen;
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}
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static void allocate_buf_for_compression(void)
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{
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struct crypto_comp *ctx;
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int size;
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char *buf;
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/* Skip if not built-in or compression backend not selected yet. */
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if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !zbackend)
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return;
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/* Skip if no pstore backend yet or compression init already done. */
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if (!psinfo || tfm)
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return;
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if (!crypto_has_comp(zbackend->name, 0, 0)) {
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pr_err("Unknown compression: %s\n", zbackend->name);
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return;
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}
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size = zbackend->zbufsize(psinfo->bufsize);
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if (size <= 0) {
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pr_err("Invalid compression size for %s: %d\n",
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zbackend->name, size);
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return;
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}
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buf = kmalloc(size, GFP_KERNEL);
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if (!buf) {
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pr_err("Failed %d byte compression buffer allocation for: %s\n",
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size, zbackend->name);
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return;
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}
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ctx = crypto_alloc_comp(zbackend->name, 0, 0);
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if (IS_ERR_OR_NULL(ctx)) {
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kfree(buf);
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pr_err("crypto_alloc_comp('%s') failed: %ld\n", zbackend->name,
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PTR_ERR(ctx));
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return;
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}
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/* A non-NULL big_oops_buf indicates compression is available. */
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tfm = ctx;
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big_oops_buf_sz = size;
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big_oops_buf = buf;
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pr_info("Using crash dump compression: %s\n", zbackend->name);
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}
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static void free_buf_for_compression(void)
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{
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if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && tfm) {
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crypto_free_comp(tfm);
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tfm = NULL;
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}
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kfree(big_oops_buf);
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big_oops_buf = NULL;
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big_oops_buf_sz = 0;
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}
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/*
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* Called when compression fails, since the printk buffer
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* would be fetched for compression calling it again when
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* compression fails would have moved the iterator of
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* printk buffer which results in fetching old contents.
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* Copy the recent messages from big_oops_buf to psinfo->buf
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*/
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static size_t copy_kmsg_to_buffer(int hsize, size_t len)
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{
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size_t total_len;
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size_t diff;
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total_len = hsize + len;
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if (total_len > psinfo->bufsize) {
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diff = total_len - psinfo->bufsize + hsize;
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memcpy(psinfo->buf, big_oops_buf, hsize);
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memcpy(psinfo->buf + hsize, big_oops_buf + diff,
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psinfo->bufsize - hsize);
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total_len = psinfo->bufsize;
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} else
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memcpy(psinfo->buf, big_oops_buf, total_len);
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return total_len;
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}
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void pstore_record_init(struct pstore_record *record,
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struct pstore_info *psinfo)
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{
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memset(record, 0, sizeof(*record));
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record->psi = psinfo;
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/* Report zeroed timestamp if called before timekeeping has resumed. */
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record->time = ns_to_timespec64(ktime_get_real_fast_ns());
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}
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/*
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* callback from kmsg_dump. Save as much as we can (up to kmsg_bytes) from the
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* end of the buffer.
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*/
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static void pstore_dump(struct kmsg_dumper *dumper,
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enum kmsg_dump_reason reason)
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{
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unsigned long total = 0;
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const char *why;
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unsigned int part = 1;
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int ret;
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why = kmsg_dump_reason_str(reason);
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if (down_trylock(&psinfo->buf_lock)) {
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/* Failed to acquire lock: give up if we cannot wait. */
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if (pstore_cannot_wait(reason)) {
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pr_err("dump skipped in %s path: may corrupt error record\n",
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in_nmi() ? "NMI" : why);
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return;
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}
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if (down_interruptible(&psinfo->buf_lock)) {
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pr_err("could not grab semaphore?!\n");
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return;
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}
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}
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oopscount++;
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while (total < kmsg_bytes) {
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char *dst;
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size_t dst_size;
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int header_size;
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int zipped_len = -1;
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size_t dump_size;
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struct pstore_record record;
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pstore_record_init(&record, psinfo);
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record.type = PSTORE_TYPE_DMESG;
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record.count = oopscount;
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record.reason = reason;
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record.part = part;
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record.buf = psinfo->buf;
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if (big_oops_buf) {
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dst = big_oops_buf;
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dst_size = big_oops_buf_sz;
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} else {
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dst = psinfo->buf;
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dst_size = psinfo->bufsize;
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}
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/* Write dump header. */
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header_size = snprintf(dst, dst_size, "%s#%d Part%u\n", why,
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oopscount, part);
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dst_size -= header_size;
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/* Write dump contents. */
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if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
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dst_size, &dump_size))
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break;
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if (big_oops_buf) {
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zipped_len = pstore_compress(dst, psinfo->buf,
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header_size + dump_size,
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psinfo->bufsize);
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if (zipped_len > 0) {
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record.compressed = true;
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record.size = zipped_len;
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} else {
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record.size = copy_kmsg_to_buffer(header_size,
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dump_size);
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}
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} else {
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record.size = header_size + dump_size;
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}
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ret = psinfo->write(&record);
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if (ret == 0 && reason == KMSG_DUMP_OOPS) {
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pstore_new_entry = 1;
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pstore_timer_kick();
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}
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total += record.size;
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part++;
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}
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up(&psinfo->buf_lock);
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}
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static struct kmsg_dumper pstore_dumper = {
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.dump = pstore_dump,
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};
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/*
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* Register with kmsg_dump to save last part of console log on panic.
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*/
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static void pstore_register_kmsg(void)
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{
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kmsg_dump_register(&pstore_dumper);
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}
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static void pstore_unregister_kmsg(void)
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{
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kmsg_dump_unregister(&pstore_dumper);
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}
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#ifdef CONFIG_PSTORE_CONSOLE
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static void pstore_console_write(struct console *con, const char *s, unsigned c)
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{
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struct pstore_record record;
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if (!c)
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return;
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pstore_record_init(&record, psinfo);
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record.type = PSTORE_TYPE_CONSOLE;
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record.buf = (char *)s;
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record.size = c;
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psinfo->write(&record);
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}
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static struct console pstore_console = {
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.write = pstore_console_write,
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.index = -1,
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};
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static void pstore_register_console(void)
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{
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/* Show which backend is going to get console writes. */
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strscpy(pstore_console.name, psinfo->name,
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sizeof(pstore_console.name));
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/*
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* Always initialize flags here since prior unregister_console()
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* calls may have changed settings (specifically CON_ENABLED).
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*/
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pstore_console.flags = CON_PRINTBUFFER | CON_ENABLED | CON_ANYTIME;
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register_console(&pstore_console);
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}
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static void pstore_unregister_console(void)
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{
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unregister_console(&pstore_console);
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}
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#else
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static void pstore_register_console(void) {}
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static void pstore_unregister_console(void) {}
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#endif
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static int pstore_write_user_compat(struct pstore_record *record,
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|
const char __user *buf)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (record->buf)
|
|
return -EINVAL;
|
|
|
|
record->buf = memdup_user(buf, record->size);
|
|
if (IS_ERR(record->buf)) {
|
|
ret = PTR_ERR(record->buf);
|
|
goto out;
|
|
}
|
|
|
|
ret = record->psi->write(record);
|
|
|
|
kfree(record->buf);
|
|
out:
|
|
record->buf = NULL;
|
|
|
|
return unlikely(ret < 0) ? ret : record->size;
|
|
}
|
|
|
|
/*
|
|
* platform specific persistent storage driver registers with
|
|
* us here. If pstore is already mounted, call the platform
|
|
* read function right away to populate the file system. If not
|
|
* then the pstore mount code will call us later to fill out
|
|
* the file system.
|
|
*/
|
|
int pstore_register(struct pstore_info *psi)
|
|
{
|
|
if (backend && strcmp(backend, psi->name)) {
|
|
pr_warn("ignoring unexpected backend '%s'\n", psi->name);
|
|
return -EPERM;
|
|
}
|
|
|
|
/* Sanity check flags. */
|
|
if (!psi->flags) {
|
|
pr_warn("backend '%s' must support at least one frontend\n",
|
|
psi->name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Check for required functions. */
|
|
if (!psi->read || !psi->write) {
|
|
pr_warn("backend '%s' must implement read() and write()\n",
|
|
psi->name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
mutex_lock(&psinfo_lock);
|
|
if (psinfo) {
|
|
pr_warn("backend '%s' already loaded: ignoring '%s'\n",
|
|
psinfo->name, psi->name);
|
|
mutex_unlock(&psinfo_lock);
|
|
return -EBUSY;
|
|
}
|
|
|
|
if (!psi->write_user)
|
|
psi->write_user = pstore_write_user_compat;
|
|
psinfo = psi;
|
|
mutex_init(&psinfo->read_mutex);
|
|
sema_init(&psinfo->buf_lock, 1);
|
|
|
|
if (psi->flags & PSTORE_FLAGS_DMESG)
|
|
allocate_buf_for_compression();
|
|
|
|
pstore_get_records(0);
|
|
|
|
if (psi->flags & PSTORE_FLAGS_DMESG) {
|
|
pstore_dumper.max_reason = psinfo->max_reason;
|
|
pstore_register_kmsg();
|
|
}
|
|
if (psi->flags & PSTORE_FLAGS_CONSOLE)
|
|
pstore_register_console();
|
|
if (psi->flags & PSTORE_FLAGS_FTRACE)
|
|
pstore_register_ftrace();
|
|
if (psi->flags & PSTORE_FLAGS_PMSG)
|
|
pstore_register_pmsg();
|
|
|
|
/* Start watching for new records, if desired. */
|
|
pstore_timer_kick();
|
|
|
|
/*
|
|
* Update the module parameter backend, so it is visible
|
|
* through /sys/module/pstore/parameters/backend
|
|
*/
|
|
backend = kstrdup(psi->name, GFP_KERNEL);
|
|
|
|
pr_info("Registered %s as persistent store backend\n", psi->name);
|
|
|
|
mutex_unlock(&psinfo_lock);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pstore_register);
|
|
|
|
void pstore_unregister(struct pstore_info *psi)
|
|
{
|
|
/* It's okay to unregister nothing. */
|
|
if (!psi)
|
|
return;
|
|
|
|
mutex_lock(&psinfo_lock);
|
|
|
|
/* Only one backend can be registered at a time. */
|
|
if (WARN_ON(psi != psinfo)) {
|
|
mutex_unlock(&psinfo_lock);
|
|
return;
|
|
}
|
|
|
|
/* Unregister all callbacks. */
|
|
if (psi->flags & PSTORE_FLAGS_PMSG)
|
|
pstore_unregister_pmsg();
|
|
if (psi->flags & PSTORE_FLAGS_FTRACE)
|
|
pstore_unregister_ftrace();
|
|
if (psi->flags & PSTORE_FLAGS_CONSOLE)
|
|
pstore_unregister_console();
|
|
if (psi->flags & PSTORE_FLAGS_DMESG)
|
|
pstore_unregister_kmsg();
|
|
|
|
/* Stop timer and make sure all work has finished. */
|
|
del_timer_sync(&pstore_timer);
|
|
flush_work(&pstore_work);
|
|
|
|
/* Remove all backend records from filesystem tree. */
|
|
pstore_put_backend_records(psi);
|
|
|
|
free_buf_for_compression();
|
|
|
|
psinfo = NULL;
|
|
kfree(backend);
|
|
backend = NULL;
|
|
mutex_unlock(&psinfo_lock);
|
|
}
|
|
EXPORT_SYMBOL_GPL(pstore_unregister);
|
|
|
|
static void decompress_record(struct pstore_record *record)
|
|
{
|
|
int ret;
|
|
int unzipped_len;
|
|
char *unzipped, *workspace;
|
|
|
|
if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !record->compressed)
|
|
return;
|
|
|
|
/* Only PSTORE_TYPE_DMESG support compression. */
|
|
if (record->type != PSTORE_TYPE_DMESG) {
|
|
pr_warn("ignored compressed record type %d\n", record->type);
|
|
return;
|
|
}
|
|
|
|
/* Missing compression buffer means compression was not initialized. */
|
|
if (!big_oops_buf) {
|
|
pr_warn("no decompression method initialized!\n");
|
|
return;
|
|
}
|
|
|
|
/* Allocate enough space to hold max decompression and ECC. */
|
|
unzipped_len = big_oops_buf_sz;
|
|
workspace = kmalloc(unzipped_len + record->ecc_notice_size,
|
|
GFP_KERNEL);
|
|
if (!workspace)
|
|
return;
|
|
|
|
/* After decompression "unzipped_len" is almost certainly smaller. */
|
|
ret = crypto_comp_decompress(tfm, record->buf, record->size,
|
|
workspace, &unzipped_len);
|
|
if (ret) {
|
|
pr_err("crypto_comp_decompress failed, ret = %d!\n", ret);
|
|
kfree(workspace);
|
|
return;
|
|
}
|
|
|
|
/* Append ECC notice to decompressed buffer. */
|
|
memcpy(workspace + unzipped_len, record->buf + record->size,
|
|
record->ecc_notice_size);
|
|
|
|
/* Copy decompressed contents into an minimum-sized allocation. */
|
|
unzipped = kmemdup(workspace, unzipped_len + record->ecc_notice_size,
|
|
GFP_KERNEL);
|
|
kfree(workspace);
|
|
if (!unzipped)
|
|
return;
|
|
|
|
/* Swap out compressed contents with decompressed contents. */
|
|
kfree(record->buf);
|
|
record->buf = unzipped;
|
|
record->size = unzipped_len;
|
|
record->compressed = false;
|
|
}
|
|
|
|
/*
|
|
* Read all the records from one persistent store backend. Create
|
|
* files in our filesystem. Don't warn about -EEXIST errors
|
|
* when we are re-scanning the backing store looking to add new
|
|
* error records.
|
|
*/
|
|
void pstore_get_backend_records(struct pstore_info *psi,
|
|
struct dentry *root, int quiet)
|
|
{
|
|
int failed = 0;
|
|
unsigned int stop_loop = 65536;
|
|
|
|
if (!psi || !root)
|
|
return;
|
|
|
|
mutex_lock(&psi->read_mutex);
|
|
if (psi->open && psi->open(psi))
|
|
goto out;
|
|
|
|
/*
|
|
* Backend callback read() allocates record.buf. decompress_record()
|
|
* may reallocate record.buf. On success, pstore_mkfile() will keep
|
|
* the record.buf, so free it only on failure.
|
|
*/
|
|
for (; stop_loop; stop_loop--) {
|
|
struct pstore_record *record;
|
|
int rc;
|
|
|
|
record = kzalloc(sizeof(*record), GFP_KERNEL);
|
|
if (!record) {
|
|
pr_err("out of memory creating record\n");
|
|
break;
|
|
}
|
|
pstore_record_init(record, psi);
|
|
|
|
record->size = psi->read(record);
|
|
|
|
/* No more records left in backend? */
|
|
if (record->size <= 0) {
|
|
kfree(record);
|
|
break;
|
|
}
|
|
|
|
decompress_record(record);
|
|
rc = pstore_mkfile(root, record);
|
|
if (rc) {
|
|
/* pstore_mkfile() did not take record, so free it. */
|
|
kfree(record->buf);
|
|
kfree(record);
|
|
if (rc != -EEXIST || !quiet)
|
|
failed++;
|
|
}
|
|
}
|
|
if (psi->close)
|
|
psi->close(psi);
|
|
out:
|
|
mutex_unlock(&psi->read_mutex);
|
|
|
|
if (failed)
|
|
pr_warn("failed to create %d record(s) from '%s'\n",
|
|
failed, psi->name);
|
|
if (!stop_loop)
|
|
pr_err("looping? Too many records seen from '%s'\n",
|
|
psi->name);
|
|
}
|
|
|
|
static void pstore_dowork(struct work_struct *work)
|
|
{
|
|
pstore_get_records(1);
|
|
}
|
|
|
|
static void pstore_timefunc(struct timer_list *unused)
|
|
{
|
|
if (pstore_new_entry) {
|
|
pstore_new_entry = 0;
|
|
schedule_work(&pstore_work);
|
|
}
|
|
|
|
pstore_timer_kick();
|
|
}
|
|
|
|
static void __init pstore_choose_compression(void)
|
|
{
|
|
const struct pstore_zbackend *step;
|
|
|
|
if (!compress)
|
|
return;
|
|
|
|
for (step = zbackends; step->name; step++) {
|
|
if (!strcmp(compress, step->name)) {
|
|
zbackend = step;
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int __init pstore_init(void)
|
|
{
|
|
int ret;
|
|
|
|
pstore_choose_compression();
|
|
|
|
/*
|
|
* Check if any pstore backends registered earlier but did not
|
|
* initialize compression because crypto was not ready. If so,
|
|
* initialize compression now.
|
|
*/
|
|
allocate_buf_for_compression();
|
|
|
|
ret = pstore_init_fs();
|
|
if (ret)
|
|
free_buf_for_compression();
|
|
|
|
return ret;
|
|
}
|
|
late_initcall(pstore_init);
|
|
|
|
static void __exit pstore_exit(void)
|
|
{
|
|
pstore_exit_fs();
|
|
}
|
|
module_exit(pstore_exit)
|
|
|
|
MODULE_AUTHOR("Tony Luck <tony.luck@intel.com>");
|
|
MODULE_LICENSE("GPL");
|