blob: 36714df37d5d81df8c9b3671cd602c7413579c58 [file] [log] [blame]
Thomas Gleixner45051532019-05-29 16:57:47 -07001// SPDX-License-Identifier: GPL-2.0-only
Tony Luckca01d6d2010-12-28 14:25:21 -08002/*
3 * Persistent Storage - platform driver interface parts.
4 *
Anton Vorontsovf29e5952012-05-26 06:20:19 -07005 * Copyright (C) 2007-2008 Google, Inc.
Tony Luckca01d6d2010-12-28 14:25:21 -08006 * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
Tony Luckca01d6d2010-12-28 14:25:21 -08007 */
8
Fabian Frederickef748852014-06-06 14:37:31 -07009#define pr_fmt(fmt) "pstore: " fmt
10
Tony Luckca01d6d2010-12-28 14:25:21 -080011#include <linux/atomic.h>
12#include <linux/types.h>
13#include <linux/errno.h>
14#include <linux/init.h>
15#include <linux/kmsg_dump.h>
Anton Vorontsovf29e5952012-05-26 06:20:19 -070016#include <linux/console.h>
Tony Luckca01d6d2010-12-28 14:25:21 -080017#include <linux/module.h>
18#include <linux/pstore.h>
Arnd Bergmann58eb5b672018-03-15 16:34:08 +010019#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
Geliang Tang8cfc8dd2016-02-18 22:04:22 +080020#include <linux/lzo.h>
21#endif
Arnd Bergmann58eb5b672018-03-15 16:34:08 +010022#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
Geliang Tang8cfc8dd2016-02-18 22:04:22 +080023#include <linux/lz4.h>
24#endif
Geliang Tang1021bcf2018-08-01 19:23:37 +080025#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
26#include <linux/zstd.h>
27#endif
Geliang Tangcb3bee02018-03-09 18:51:07 +080028#include <linux/crypto.h>
Tony Luckca01d6d2010-12-28 14:25:21 -080029#include <linux/string.h>
Luck, Tony6dda9262011-08-11 15:14:39 -070030#include <linux/timer.h>
Tony Luckca01d6d2010-12-28 14:25:21 -080031#include <linux/slab.h>
32#include <linux/uaccess.h>
Anton Vorontsova3f5f072012-05-26 06:20:28 -070033#include <linux/jiffies.h>
Luck, Tony6dda9262011-08-11 15:14:39 -070034#include <linux/workqueue.h>
Tony Luckca01d6d2010-12-28 14:25:21 -080035
36#include "internal.h"
37
38/*
Luck, Tony6dda9262011-08-11 15:14:39 -070039 * We defer making "oops" entries appear in pstore - see
40 * whether the system is actually still running well enough
41 * to let someone see the entry
42 */
Anton Vorontsov521f72882012-05-26 06:20:29 -070043static int pstore_update_ms = -1;
Anton Vorontsova3f5f072012-05-26 06:20:28 -070044module_param_named(update_ms, pstore_update_ms, int, 0600);
45MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content "
Anton Vorontsov521f72882012-05-26 06:20:29 -070046 "(default is -1, which means runtime updates are disabled; "
Kees Cook78c83c82020-05-05 21:36:15 -070047 "enabling this option may not be safe; it may lead to further "
Anton Vorontsov521f72882012-05-26 06:20:29 -070048 "corruption on Oopses)");
Luck, Tony6dda9262011-08-11 15:14:39 -070049
Joel Fernandes (Google)f0f23e52018-11-03 16:38:16 -070050/* Names should be in the same order as the enum pstore_type_id */
51static const char * const pstore_type_names[] = {
52 "dmesg",
53 "mce",
54 "console",
55 "ftrace",
56 "rtas",
57 "powerpc-ofw",
58 "powerpc-common",
59 "pmsg",
60 "powerpc-opal",
61};
62
Luck, Tony6dda9262011-08-11 15:14:39 -070063static int pstore_new_entry;
64
Kees Cook24ed9602017-08-28 11:28:21 -070065static void pstore_timefunc(struct timer_list *);
Kees Cook1d27e3e2017-10-04 16:27:04 -070066static DEFINE_TIMER(pstore_timer, pstore_timefunc);
Luck, Tony6dda9262011-08-11 15:14:39 -070067
68static void pstore_dowork(struct work_struct *);
69static DECLARE_WORK(pstore_work, pstore_dowork);
70
71/*
Kees Cook6248a0662020-05-04 19:33:54 -070072 * psinfo_lock protects "psinfo" during calls to
73 * pstore_register(), pstore_unregister(), and
74 * the filesystem mount/unmount routines.
Tony Luckca01d6d2010-12-28 14:25:21 -080075 */
Kees Cookcab12fd2020-05-04 19:31:36 -070076static DEFINE_MUTEX(psinfo_lock);
Anton Vorontsov060287b2012-07-09 17:10:41 -070077struct pstore_info *psinfo;
Tony Luckca01d6d2010-12-28 14:25:21 -080078
Matthew Garrettdee28e72011-07-21 16:57:55 -040079static char *backend;
Kees Cookd973f7d2020-05-08 09:25:19 -070080module_param(backend, charp, 0444);
81MODULE_PARM_DESC(backend, "specific backend to use");
82
Kees Cookfe1d4752018-03-06 15:57:38 -080083static char *compress =
84#ifdef CONFIG_PSTORE_COMPRESS_DEFAULT
85 CONFIG_PSTORE_COMPRESS_DEFAULT;
86#else
87 NULL;
88#endif
Kees Cookd973f7d2020-05-08 09:25:19 -070089module_param(compress, charp, 0444);
90MODULE_PARM_DESC(compress, "compression to use");
Matthew Garrettdee28e72011-07-21 16:57:55 -040091
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -070092/* Compression parameters */
Geliang Tangcb3bee02018-03-09 18:51:07 +080093static struct crypto_comp *tfm;
Geliang Tang8cfc8dd2016-02-18 22:04:22 +080094
95struct pstore_zbackend {
Geliang Tangcb3bee02018-03-09 18:51:07 +080096 int (*zbufsize)(size_t size);
Geliang Tang8cfc8dd2016-02-18 22:04:22 +080097 const char *name;
98};
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -070099
100static char *big_oops_buf;
101static size_t big_oops_buf_sz;
102
Luck, Tony366f7e72011-03-18 15:33:43 -0700103/* How much of the console log to snapshot */
David Howells349d7432017-07-05 16:24:34 +0100104unsigned long kmsg_bytes = PSTORE_DEFAULT_KMSG_BYTES;
Tony Luckca01d6d2010-12-28 14:25:21 -0800105
Luck, Tony366f7e72011-03-18 15:33:43 -0700106void pstore_set_kmsg_bytes(int bytes)
Tony Luckca01d6d2010-12-28 14:25:21 -0800107{
Luck, Tony366f7e72011-03-18 15:33:43 -0700108 kmsg_bytes = bytes;
Tony Luckca01d6d2010-12-28 14:25:21 -0800109}
110
Tony Luckca01d6d2010-12-28 14:25:21 -0800111/* Tag each group of saved records with a sequence number */
112static int oopscount;
113
Joel Fernandes (Google)f0f23e52018-11-03 16:38:16 -0700114const char *pstore_type_to_name(enum pstore_type_id type)
115{
116 BUILD_BUG_ON(ARRAY_SIZE(pstore_type_names) != PSTORE_TYPE_MAX);
117
118 if (WARN_ON_ONCE(type >= PSTORE_TYPE_MAX))
119 return "unknown";
120
121 return pstore_type_names[type];
122}
123EXPORT_SYMBOL_GPL(pstore_type_to_name);
124
125enum pstore_type_id pstore_name_to_type(const char *name)
126{
127 int i;
128
129 for (i = 0; i < PSTORE_TYPE_MAX; i++) {
130 if (!strcmp(pstore_type_names[i], name))
131 return i;
132 }
133
134 return PSTORE_TYPE_MAX;
135}
136EXPORT_SYMBOL_GPL(pstore_name_to_type);
137
Kees Cook78c83c82020-05-05 21:36:15 -0700138static void pstore_timer_kick(void)
139{
140 if (pstore_update_ms < 0)
141 return;
142
143 mod_timer(&pstore_timer, jiffies + msecs_to_jiffies(pstore_update_ms));
144}
145
Kees Cookea84b582018-11-30 14:36:58 -0800146/*
147 * Should pstore_dump() wait for a concurrent pstore_dump()? If
148 * not, the current pstore_dump() will report a failure to dump
149 * and return.
150 */
151static bool pstore_cannot_wait(enum kmsg_dump_reason reason)
Seiji Aguchi9f244e92013-01-11 18:09:41 +0000152{
Kees Cookea84b582018-11-30 14:36:58 -0800153 /* In NMI path, pstore shouldn't block regardless of reason. */
Seiji Aguchi9f244e92013-01-11 18:09:41 +0000154 if (in_nmi())
155 return true;
156
157 switch (reason) {
158 /* In panic case, other cpus are stopped by smp_send_stop(). */
159 case KMSG_DUMP_PANIC:
Kees Cookea84b582018-11-30 14:36:58 -0800160 /* Emergency restart shouldn't be blocked. */
Seiji Aguchi9f244e92013-01-11 18:09:41 +0000161 case KMSG_DUMP_EMERG:
162 return true;
163 default:
164 return false;
165 }
166}
Seiji Aguchi9f244e92013-01-11 18:09:41 +0000167
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100168#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
Geliang Tangcb3bee02018-03-09 18:51:07 +0800169static int zbufsize_deflate(size_t size)
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700170{
Aruna Balakrishnaiah7de8fe22013-09-11 10:57:41 -0700171 size_t cmpr;
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700172
Geliang Tangcb3bee02018-03-09 18:51:07 +0800173 switch (size) {
Aruna Balakrishnaiah7de8fe22013-09-11 10:57:41 -0700174 /* buffer range for efivars */
175 case 1000 ... 2000:
176 cmpr = 56;
177 break;
178 case 2001 ... 3000:
179 cmpr = 54;
180 break;
181 case 3001 ... 3999:
182 cmpr = 52;
183 break;
184 /* buffer range for nvram, erst */
185 case 4000 ... 10000:
186 cmpr = 45;
187 break;
188 default:
189 cmpr = 60;
190 break;
191 }
192
Geliang Tangcb3bee02018-03-09 18:51:07 +0800193 return (size * 100) / cmpr;
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800194}
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800195#endif
196
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100197#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
Geliang Tangcb3bee02018-03-09 18:51:07 +0800198static int zbufsize_lzo(size_t size)
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800199{
Geliang Tangcb3bee02018-03-09 18:51:07 +0800200 return lzo1x_worst_compress(size);
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800201}
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800202#endif
203
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100204#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS) || IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
Geliang Tangcb3bee02018-03-09 18:51:07 +0800205static int zbufsize_lz4(size_t size)
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800206{
Geliang Tangcb3bee02018-03-09 18:51:07 +0800207 return LZ4_compressBound(size);
Geliang Tang239b7162018-02-13 14:40:39 +0800208}
Geliang Tang239b7162018-02-13 14:40:39 +0800209#endif
210
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100211#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS)
Geliang Tangcb3bee02018-03-09 18:51:07 +0800212static int zbufsize_842(size_t size)
Geliang Tang239b7162018-02-13 14:40:39 +0800213{
Kees Cook55597402018-03-06 15:15:24 -0800214 return size;
Geliang Tang239b7162018-02-13 14:40:39 +0800215}
Kees Cookfe1d4752018-03-06 15:57:38 -0800216#endif
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800217
Geliang Tang1021bcf2018-08-01 19:23:37 +0800218#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
219static int zbufsize_zstd(size_t size)
220{
221 return ZSTD_compressBound(size);
222}
223#endif
224
Kees Cookfe1d4752018-03-06 15:57:38 -0800225static const struct pstore_zbackend *zbackend __ro_after_init;
226
227static const struct pstore_zbackend zbackends[] = {
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100228#if IS_ENABLED(CONFIG_PSTORE_DEFLATE_COMPRESS)
Kees Cookfe1d4752018-03-06 15:57:38 -0800229 {
Geliang Tangcb3bee02018-03-09 18:51:07 +0800230 .zbufsize = zbufsize_deflate,
231 .name = "deflate",
Kees Cookfe1d4752018-03-06 15:57:38 -0800232 },
233#endif
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100234#if IS_ENABLED(CONFIG_PSTORE_LZO_COMPRESS)
Kees Cookfe1d4752018-03-06 15:57:38 -0800235 {
Geliang Tangcb3bee02018-03-09 18:51:07 +0800236 .zbufsize = zbufsize_lzo,
Kees Cookfe1d4752018-03-06 15:57:38 -0800237 .name = "lzo",
238 },
239#endif
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100240#if IS_ENABLED(CONFIG_PSTORE_LZ4_COMPRESS)
Kees Cookfe1d4752018-03-06 15:57:38 -0800241 {
Geliang Tangcb3bee02018-03-09 18:51:07 +0800242 .zbufsize = zbufsize_lz4,
Kees Cookfe1d4752018-03-06 15:57:38 -0800243 .name = "lz4",
244 },
245#endif
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100246#if IS_ENABLED(CONFIG_PSTORE_LZ4HC_COMPRESS)
Kees Cookfe1d4752018-03-06 15:57:38 -0800247 {
Geliang Tangcb3bee02018-03-09 18:51:07 +0800248 .zbufsize = zbufsize_lz4,
Kees Cookfe1d4752018-03-06 15:57:38 -0800249 .name = "lz4hc",
250 },
251#endif
Arnd Bergmann58eb5b672018-03-15 16:34:08 +0100252#if IS_ENABLED(CONFIG_PSTORE_842_COMPRESS)
Kees Cookfe1d4752018-03-06 15:57:38 -0800253 {
Geliang Tangcb3bee02018-03-09 18:51:07 +0800254 .zbufsize = zbufsize_842,
Kees Cookfe1d4752018-03-06 15:57:38 -0800255 .name = "842",
256 },
257#endif
Geliang Tang1021bcf2018-08-01 19:23:37 +0800258#if IS_ENABLED(CONFIG_PSTORE_ZSTD_COMPRESS)
259 {
260 .zbufsize = zbufsize_zstd,
261 .name = "zstd",
262 },
263#endif
Kees Cookfe1d4752018-03-06 15:57:38 -0800264 { }
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800265};
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800266
267static int pstore_compress(const void *in, void *out,
Geliang Tangcb3bee02018-03-09 18:51:07 +0800268 unsigned int inlen, unsigned int outlen)
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800269{
Geliang Tangcb3bee02018-03-09 18:51:07 +0800270 int ret;
271
Matteo Crocefd49e032020-07-06 19:37:36 -0700272 if (!IS_ENABLED(CONFIG_PSTORE_COMPRESSION))
273 return -EINVAL;
274
Geliang Tangcb3bee02018-03-09 18:51:07 +0800275 ret = crypto_comp_compress(tfm, in, inlen, out, &outlen);
276 if (ret) {
277 pr_err("crypto_comp_compress failed, ret = %d!\n", ret);
278 return ret;
279 }
280
281 return outlen;
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800282}
283
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800284static void allocate_buf_for_compression(void)
285{
Kees Cook95047b02018-10-17 14:00:12 -0700286 struct crypto_comp *ctx;
287 int size;
288 char *buf;
289
290 /* Skip if not built-in or compression backend not selected yet. */
Tobias Regnerye698aaf2018-04-06 09:25:17 +0200291 if (!IS_ENABLED(CONFIG_PSTORE_COMPRESS) || !zbackend)
Geliang Tangcb3bee02018-03-09 18:51:07 +0800292 return;
293
Kees Cook95047b02018-10-17 14:00:12 -0700294 /* Skip if no pstore backend yet or compression init already done. */
295 if (!psinfo || tfm)
296 return;
297
Geliang Tangcb3bee02018-03-09 18:51:07 +0800298 if (!crypto_has_comp(zbackend->name, 0, 0)) {
Kees Cook95047b02018-10-17 14:00:12 -0700299 pr_err("Unknown compression: %s\n", zbackend->name);
Geliang Tangcb3bee02018-03-09 18:51:07 +0800300 return;
301 }
302
Kees Cook95047b02018-10-17 14:00:12 -0700303 size = zbackend->zbufsize(psinfo->bufsize);
304 if (size <= 0) {
305 pr_err("Invalid compression size for %s: %d\n",
306 zbackend->name, size);
Geliang Tangcb3bee02018-03-09 18:51:07 +0800307 return;
308 }
309
Kees Cook95047b02018-10-17 14:00:12 -0700310 buf = kmalloc(size, GFP_KERNEL);
311 if (!buf) {
312 pr_err("Failed %d byte compression buffer allocation for: %s\n",
313 size, zbackend->name);
Geliang Tangcb3bee02018-03-09 18:51:07 +0800314 return;
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800315 }
Kees Cook95047b02018-10-17 14:00:12 -0700316
317 ctx = crypto_alloc_comp(zbackend->name, 0, 0);
318 if (IS_ERR_OR_NULL(ctx)) {
319 kfree(buf);
320 pr_err("crypto_alloc_comp('%s') failed: %ld\n", zbackend->name,
321 PTR_ERR(ctx));
322 return;
323 }
324
325 /* A non-NULL big_oops_buf indicates compression is available. */
326 tfm = ctx;
327 big_oops_buf_sz = size;
328 big_oops_buf = buf;
329
Kees Cook0eed84f2018-11-01 14:03:07 -0700330 pr_info("Using crash dump compression: %s\n", zbackend->name);
Geliang Tang8cfc8dd2016-02-18 22:04:22 +0800331}
332
333static void free_buf_for_compression(void)
334{
Pi-Hsun Shiha9fb94a2019-05-20 14:51:19 +0800335 if (IS_ENABLED(CONFIG_PSTORE_COMPRESS) && tfm) {
Geliang Tangcb3bee02018-03-09 18:51:07 +0800336 crypto_free_comp(tfm);
Pi-Hsun Shiha9fb94a2019-05-20 14:51:19 +0800337 tfm = NULL;
338 }
Geliang Tangcb3bee02018-03-09 18:51:07 +0800339 kfree(big_oops_buf);
340 big_oops_buf = NULL;
341 big_oops_buf_sz = 0;
Geliang Tangee1d2672015-10-20 00:39:03 -0700342}
343
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700344/*
345 * Called when compression fails, since the printk buffer
346 * would be fetched for compression calling it again when
347 * compression fails would have moved the iterator of
348 * printk buffer which results in fetching old contents.
349 * Copy the recent messages from big_oops_buf to psinfo->buf
350 */
351static size_t copy_kmsg_to_buffer(int hsize, size_t len)
352{
353 size_t total_len;
354 size_t diff;
355
356 total_len = hsize + len;
357
358 if (total_len > psinfo->bufsize) {
359 diff = total_len - psinfo->bufsize + hsize;
360 memcpy(psinfo->buf, big_oops_buf, hsize);
361 memcpy(psinfo->buf + hsize, big_oops_buf + diff,
362 psinfo->bufsize - hsize);
363 total_len = psinfo->bufsize;
364 } else
365 memcpy(psinfo->buf, big_oops_buf, total_len);
366
367 return total_len;
368}
369
Kees Cooke581ca82017-05-19 15:10:31 -0700370void pstore_record_init(struct pstore_record *record,
371 struct pstore_info *psinfo)
372{
373 memset(record, 0, sizeof(*record));
374
375 record->psi = psinfo;
Kees Cookc7f3c5952017-05-19 15:29:10 -0700376
377 /* Report zeroed timestamp if called before timekeeping has resumed. */
Kees Cook7aaa8222018-05-14 15:50:52 -0700378 record->time = ns_to_timespec64(ktime_get_real_fast_ns());
Kees Cooke581ca82017-05-19 15:10:31 -0700379}
380
Tony Luckca01d6d2010-12-28 14:25:21 -0800381/*
Kees Cook0eed84f2018-11-01 14:03:07 -0700382 * callback from kmsg_dump. Save as much as we can (up to kmsg_bytes) from the
383 * end of the buffer.
Tony Luckca01d6d2010-12-28 14:25:21 -0800384 */
385static void pstore_dump(struct kmsg_dumper *dumper,
Kay Sieverse2ae7152012-06-15 14:07:51 +0200386 enum kmsg_dump_reason reason)
Tony Luckca01d6d2010-12-28 14:25:21 -0800387{
Kay Sieverse2ae7152012-06-15 14:07:51 +0200388 unsigned long total = 0;
Seiji Aguchi381b8722012-03-16 15:36:59 -0700389 const char *why;
Matthew Garrettb94fdd02011-07-21 16:57:54 -0400390 unsigned int part = 1;
Kay Sieverse2ae7152012-06-15 14:07:51 +0200391 int ret;
Tony Luckca01d6d2010-12-28 14:25:21 -0800392
Kees Cookfb13cb82020-05-07 19:36:22 -0700393 why = kmsg_dump_reason_str(reason);
Tony Luck9f6af272011-03-22 16:01:49 -0700394
Kees Cookea84b582018-11-30 14:36:58 -0800395 if (down_trylock(&psinfo->buf_lock)) {
396 /* Failed to acquire lock: give up if we cannot wait. */
397 if (pstore_cannot_wait(reason)) {
398 pr_err("dump skipped in %s path: may corrupt error record\n",
399 in_nmi() ? "NMI" : why);
Li Pengcheng959217c82016-11-05 10:15:59 +0800400 return;
Seiji Aguchi9f244e92013-01-11 18:09:41 +0000401 }
Kees Cookea84b582018-11-30 14:36:58 -0800402 if (down_interruptible(&psinfo->buf_lock)) {
403 pr_err("could not grab semaphore?!\n");
404 return;
405 }
Namhyung Kim98e44fda2016-05-18 21:00:05 +0900406 }
Kees Cookea84b582018-11-30 14:36:58 -0800407
Tony Luckca01d6d2010-12-28 14:25:21 -0800408 oopscount++;
409 while (total < kmsg_bytes) {
Kay Sieverse2ae7152012-06-15 14:07:51 +0200410 char *dst;
Kees Cook76cc9582017-03-03 23:28:53 -0800411 size_t dst_size;
412 int header_size;
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700413 int zipped_len = -1;
Kees Cook76cc9582017-03-03 23:28:53 -0800414 size_t dump_size;
Kees Cooke581ca82017-05-19 15:10:31 -0700415 struct pstore_record record;
416
417 pstore_record_init(&record, psinfo);
418 record.type = PSTORE_TYPE_DMESG;
419 record.count = oopscount;
420 record.reason = reason;
421 record.part = part;
422 record.buf = psinfo->buf;
Kay Sieverse2ae7152012-06-15 14:07:51 +0200423
Kees Cookea84b582018-11-30 14:36:58 -0800424 if (big_oops_buf) {
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700425 dst = big_oops_buf;
Kees Cook76cc9582017-03-03 23:28:53 -0800426 dst_size = big_oops_buf_sz;
Namhyung Kim235f6d12016-05-18 21:00:06 +0900427 } else {
428 dst = psinfo->buf;
Kees Cook76cc9582017-03-03 23:28:53 -0800429 dst_size = psinfo->bufsize;
Namhyung Kim235f6d12016-05-18 21:00:06 +0900430 }
Tony Luckca01d6d2010-12-28 14:25:21 -0800431
Kees Cook76cc9582017-03-03 23:28:53 -0800432 /* Write dump header. */
433 header_size = snprintf(dst, dst_size, "%s#%d Part%u\n", why,
434 oopscount, part);
435 dst_size -= header_size;
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700436
Kees Cook76cc9582017-03-03 23:28:53 -0800437 /* Write dump contents. */
438 if (!kmsg_dump_get_buffer(dumper, true, dst + header_size,
439 dst_size, &dump_size))
Namhyung Kim235f6d12016-05-18 21:00:06 +0900440 break;
441
Kees Cookea84b582018-11-30 14:36:58 -0800442 if (big_oops_buf) {
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700443 zipped_len = pstore_compress(dst, psinfo->buf,
Kees Cook76cc9582017-03-03 23:28:53 -0800444 header_size + dump_size,
445 psinfo->bufsize);
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700446
447 if (zipped_len > 0) {
Kees Cook76cc9582017-03-03 23:28:53 -0800448 record.compressed = true;
449 record.size = zipped_len;
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700450 } else {
Kees Cook76cc9582017-03-03 23:28:53 -0800451 record.size = copy_kmsg_to_buffer(header_size,
452 dump_size);
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700453 }
454 } else {
Kees Cook76cc9582017-03-03 23:28:53 -0800455 record.size = header_size + dump_size;
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700456 }
Tony Luckca01d6d2010-12-28 14:25:21 -0800457
Kees Cook76cc9582017-03-03 23:28:53 -0800458 ret = psinfo->write(&record);
Kees Cook78c83c82020-05-05 21:36:15 -0700459 if (ret == 0 && reason == KMSG_DUMP_OOPS) {
Luck, Tony6dda9262011-08-11 15:14:39 -0700460 pstore_new_entry = 1;
Kees Cook78c83c82020-05-05 21:36:15 -0700461 pstore_timer_kick();
462 }
Kay Sieverse2ae7152012-06-15 14:07:51 +0200463
Kees Cook76cc9582017-03-03 23:28:53 -0800464 total += record.size;
Matthew Garrett56280682011-07-21 16:57:53 -0400465 part++;
Tony Luckca01d6d2010-12-28 14:25:21 -0800466 }
Kees Cookea84b582018-11-30 14:36:58 -0800467
468 up(&psinfo->buf_lock);
Tony Luckca01d6d2010-12-28 14:25:21 -0800469}
470
471static struct kmsg_dumper pstore_dumper = {
472 .dump = pstore_dump,
473};
474
Geliang Tang306e5c22015-10-31 23:23:15 +0800475/*
476 * Register with kmsg_dump to save last part of console log on panic.
477 */
Geliang Tang18730412015-10-20 00:39:02 -0700478static void pstore_register_kmsg(void)
479{
480 kmsg_dump_register(&pstore_dumper);
481}
482
Geliang Tangee1d2672015-10-20 00:39:03 -0700483static void pstore_unregister_kmsg(void)
484{
485 kmsg_dump_unregister(&pstore_dumper);
486}
487
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700488#ifdef CONFIG_PSTORE_CONSOLE
489static void pstore_console_write(struct console *con, const char *s, unsigned c)
490{
Kees Cookb77fa612018-11-01 14:08:07 -0700491 struct pstore_record record;
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700492
Yue Hu4c6c4d32019-01-31 18:12:46 +0800493 if (!c)
494 return;
495
Kees Cookb77fa612018-11-01 14:08:07 -0700496 pstore_record_init(&record, psinfo);
497 record.type = PSTORE_TYPE_CONSOLE;
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700498
Kees Cookb77fa612018-11-01 14:08:07 -0700499 record.buf = (char *)s;
500 record.size = c;
501 psinfo->write(&record);
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700502}
503
504static struct console pstore_console = {
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700505 .write = pstore_console_write,
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700506 .index = -1,
507};
508
509static void pstore_register_console(void)
510{
Kees Cookd195c392020-05-08 09:26:28 -0700511 /* Show which backend is going to get console writes. */
512 strscpy(pstore_console.name, psinfo->name,
513 sizeof(pstore_console.name));
Kees Cookb7753fc2020-05-06 16:34:42 -0700514 /*
515 * Always initialize flags here since prior unregister_console()
516 * calls may have changed settings (specifically CON_ENABLED).
517 */
518 pstore_console.flags = CON_PRINTBUFFER | CON_ENABLED | CON_ANYTIME;
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700519 register_console(&pstore_console);
520}
Geliang Tangee1d2672015-10-20 00:39:03 -0700521
522static void pstore_unregister_console(void)
523{
524 unregister_console(&pstore_console);
525}
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700526#else
527static void pstore_register_console(void) {}
Geliang Tangee1d2672015-10-20 00:39:03 -0700528static void pstore_unregister_console(void) {}
Anton Vorontsovf29e5952012-05-26 06:20:19 -0700529#endif
530
Kees Cook4c9ec212017-03-05 22:41:10 -0800531static int pstore_write_user_compat(struct pstore_record *record,
532 const char __user *buf)
Mark Salyzyn5bf6d1b2016-09-01 08:13:46 -0700533{
Kees Cook30800d92017-03-07 13:57:11 -0800534 int ret = 0;
Mark Salyzyn5bf6d1b2016-09-01 08:13:46 -0700535
Kees Cook30800d92017-03-07 13:57:11 -0800536 if (record->buf)
537 return -EINVAL;
Mark Salyzyn5bf6d1b2016-09-01 08:13:46 -0700538
Geliang Tang077090a2017-04-29 09:45:16 +0800539 record->buf = memdup_user(buf, record->size);
Hirofumi Nakagawadfd6fa32017-09-26 03:21:27 +0900540 if (IS_ERR(record->buf)) {
Geliang Tang077090a2017-04-29 09:45:16 +0800541 ret = PTR_ERR(record->buf);
Kees Cook30800d92017-03-07 13:57:11 -0800542 goto out;
Mark Salyzyn5bf6d1b2016-09-01 08:13:46 -0700543 }
Kees Cook30800d92017-03-07 13:57:11 -0800544
545 ret = record->psi->write(record);
546
Kees Cook30800d92017-03-07 13:57:11 -0800547 kfree(record->buf);
Geliang Tang077090a2017-04-29 09:45:16 +0800548out:
Kees Cook30800d92017-03-07 13:57:11 -0800549 record->buf = NULL;
550
551 return unlikely(ret < 0) ? ret : record->size;
Mark Salyzyn5bf6d1b2016-09-01 08:13:46 -0700552}
553
Tony Luckca01d6d2010-12-28 14:25:21 -0800554/*
555 * platform specific persistent storage driver registers with
556 * us here. If pstore is already mounted, call the platform
557 * read function right away to populate the file system. If not
558 * then the pstore mount code will call us later to fill out
559 * the file system.
Tony Luckca01d6d2010-12-28 14:25:21 -0800560 */
561int pstore_register(struct pstore_info *psi)
562{
Kees Cook0d7cd092017-03-03 12:11:40 -0800563 if (backend && strcmp(backend, psi->name)) {
564 pr_warn("ignoring unexpected backend '%s'\n", psi->name);
Lenny Szubowicz8e48b1a2013-06-28 17:11:33 -0400565 return -EPERM;
Kees Cook0d7cd092017-03-03 12:11:40 -0800566 }
Lenny Szubowicz8e48b1a2013-06-28 17:11:33 -0400567
Kees Cook4c9ec212017-03-05 22:41:10 -0800568 /* Sanity check flags. */
569 if (!psi->flags) {
570 pr_warn("backend '%s' must support at least one frontend\n",
571 psi->name);
572 return -EINVAL;
573 }
574
575 /* Check for required functions. */
576 if (!psi->read || !psi->write) {
577 pr_warn("backend '%s' must implement read() and write()\n",
578 psi->name);
579 return -EINVAL;
580 }
581
Kees Cookcab12fd2020-05-04 19:31:36 -0700582 mutex_lock(&psinfo_lock);
Tony Luckca01d6d2010-12-28 14:25:21 -0800583 if (psinfo) {
Kees Cook0d7cd092017-03-03 12:11:40 -0800584 pr_warn("backend '%s' already loaded: ignoring '%s'\n",
585 psinfo->name, psi->name);
Kees Cookcab12fd2020-05-04 19:31:36 -0700586 mutex_unlock(&psinfo_lock);
Tony Luckca01d6d2010-12-28 14:25:21 -0800587 return -EBUSY;
588 }
Matthew Garrettdee28e72011-07-21 16:57:55 -0400589
Kees Cook4c9ec212017-03-05 22:41:10 -0800590 if (!psi->write_user)
591 psi->write_user = pstore_write_user_compat;
Tony Luckca01d6d2010-12-28 14:25:21 -0800592 psinfo = psi;
Kees Cookf6f82852011-11-17 12:58:07 -0800593 mutex_init(&psinfo->read_mutex);
Kees Cookea84b582018-11-30 14:36:58 -0800594 sema_init(&psinfo->buf_lock, 1);
Tony Luckca01d6d2010-12-28 14:25:21 -0800595
Kees Cook8880fa32019-05-30 23:37:29 -0700596 if (psi->flags & PSTORE_FLAGS_DMESG)
597 allocate_buf_for_compression();
Aruna Balakrishnaiahb0aad7a2013-08-16 13:53:10 -0700598
Kees Cook27e50412020-05-04 19:43:41 -0700599 pstore_get_records(0);
Tony Luckca01d6d2010-12-28 14:25:21 -0800600
Pavel Tatashin3524e682020-05-05 11:45:07 -0400601 if (psi->flags & PSTORE_FLAGS_DMESG) {
602 pstore_dumper.max_reason = psinfo->max_reason;
Namhyung Kimc950fd62016-07-28 00:08:25 +0900603 pstore_register_kmsg();
Pavel Tatashin3524e682020-05-05 11:45:07 -0400604 }
Namhyung Kimc950fd62016-07-28 00:08:25 +0900605 if (psi->flags & PSTORE_FLAGS_CONSOLE)
Luck, Tonydf36ac12013-12-18 15:17:10 -0800606 pstore_register_console();
Namhyung Kimc950fd62016-07-28 00:08:25 +0900607 if (psi->flags & PSTORE_FLAGS_FTRACE)
Luck, Tonydf36ac12013-12-18 15:17:10 -0800608 pstore_register_ftrace();
Namhyung Kimc950fd62016-07-28 00:08:25 +0900609 if (psi->flags & PSTORE_FLAGS_PMSG)
Mark Salyzyn9d5438f2015-01-16 16:01:10 -0800610 pstore_register_pmsg();
Tony Luckca01d6d2010-12-28 14:25:21 -0800611
Kees Cook6330d552017-03-06 12:42:12 -0800612 /* Start watching for new records, if desired. */
Kees Cook78c83c82020-05-05 21:36:15 -0700613 pstore_timer_kick();
Luck, Tony6dda9262011-08-11 15:14:39 -0700614
Wang Long42222c22015-05-21 09:34:22 -0700615 /*
616 * Update the module parameter backend, so it is visible
617 * through /sys/module/pstore/parameters/backend
618 */
Kees Cook563ca402020-05-08 09:16:02 -0700619 backend = kstrdup(psi->name, GFP_KERNEL);
Wang Long42222c22015-05-21 09:34:22 -0700620
Fabian Frederickef748852014-06-06 14:37:31 -0700621 pr_info("Registered %s as persistent store backend\n", psi->name);
Lenny Szubowicz8e48b1a2013-06-28 17:11:33 -0400622
Kees Cook6248a0662020-05-04 19:33:54 -0700623 mutex_unlock(&psinfo_lock);
Tony Luckca01d6d2010-12-28 14:25:21 -0800624 return 0;
625}
626EXPORT_SYMBOL_GPL(pstore_register);
627
Geliang Tangee1d2672015-10-20 00:39:03 -0700628void pstore_unregister(struct pstore_info *psi)
629{
Kees Cook6248a0662020-05-04 19:33:54 -0700630 /* It's okay to unregister nothing. */
631 if (!psi)
632 return;
633
634 mutex_lock(&psinfo_lock);
635
636 /* Only one backend can be registered at a time. */
637 if (WARN_ON(psi != psinfo)) {
638 mutex_unlock(&psinfo_lock);
639 return;
640 }
641
Kees Cook78c83c82020-05-05 21:36:15 -0700642 /* Unregister all callbacks. */
Namhyung Kimc950fd62016-07-28 00:08:25 +0900643 if (psi->flags & PSTORE_FLAGS_PMSG)
Kees Cooka1db8062016-05-19 10:59:03 -0400644 pstore_unregister_pmsg();
Namhyung Kimc950fd62016-07-28 00:08:25 +0900645 if (psi->flags & PSTORE_FLAGS_FTRACE)
Kees Cooka1db8062016-05-19 10:59:03 -0400646 pstore_unregister_ftrace();
Namhyung Kimc950fd62016-07-28 00:08:25 +0900647 if (psi->flags & PSTORE_FLAGS_CONSOLE)
Kees Cooka1db8062016-05-19 10:59:03 -0400648 pstore_unregister_console();
Namhyung Kimc950fd62016-07-28 00:08:25 +0900649 if (psi->flags & PSTORE_FLAGS_DMESG)
650 pstore_unregister_kmsg();
Geliang Tangee1d2672015-10-20 00:39:03 -0700651
Kees Cook78c83c82020-05-05 21:36:15 -0700652 /* Stop timer and make sure all work has finished. */
653 del_timer_sync(&pstore_timer);
654 flush_work(&pstore_work);
655
Kees Cook609e28bb2020-05-04 19:46:53 -0700656 /* Remove all backend records from filesystem tree. */
657 pstore_put_backend_records(psi);
658
Geliang Tangee1d2672015-10-20 00:39:03 -0700659 free_buf_for_compression();
660
661 psinfo = NULL;
Kees Cook563ca402020-05-08 09:16:02 -0700662 kfree(backend);
Geliang Tangee1d2672015-10-20 00:39:03 -0700663 backend = NULL;
Kees Cook6248a0662020-05-04 19:33:54 -0700664 mutex_unlock(&psinfo_lock);
Geliang Tangee1d2672015-10-20 00:39:03 -0700665}
666EXPORT_SYMBOL_GPL(pstore_unregister);
667
Kees Cook634f8f52017-03-03 17:35:25 -0800668static void decompress_record(struct pstore_record *record)
669{
Kees Cookbdabc8e2018-10-26 01:17:07 -0700670 int ret;
Kees Cook634f8f52017-03-03 17:35:25 -0800671 int unzipped_len;
Kees Cookbdabc8e2018-10-26 01:17:07 -0700672 char *unzipped, *workspace;
Kees Cook634f8f52017-03-03 17:35:25 -0800673
Matteo Crocefd49e032020-07-06 19:37:36 -0700674 if (!IS_ENABLED(CONFIG_PSTORE_COMPRESSION) || !record->compressed)
Ankit Kumar4a16d1c2017-05-23 11:16:52 +0530675 return;
676
Kees Cook634f8f52017-03-03 17:35:25 -0800677 /* Only PSTORE_TYPE_DMESG support compression. */
Ankit Kumar4a16d1c2017-05-23 11:16:52 +0530678 if (record->type != PSTORE_TYPE_DMESG) {
Kees Cook634f8f52017-03-03 17:35:25 -0800679 pr_warn("ignored compressed record type %d\n", record->type);
680 return;
681 }
682
Kees Cookbdabc8e2018-10-26 01:17:07 -0700683 /* Missing compression buffer means compression was not initialized. */
Kees Cook634f8f52017-03-03 17:35:25 -0800684 if (!big_oops_buf) {
Kees Cookbdabc8e2018-10-26 01:17:07 -0700685 pr_warn("no decompression method initialized!\n");
Kees Cook634f8f52017-03-03 17:35:25 -0800686 return;
687 }
688
Kees Cookbdabc8e2018-10-26 01:17:07 -0700689 /* Allocate enough space to hold max decompression and ECC. */
690 unzipped_len = big_oops_buf_sz;
691 workspace = kmalloc(unzipped_len + record->ecc_notice_size,
692 GFP_KERNEL);
693 if (!workspace)
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800694 return;
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800695
Kees Cookbdabc8e2018-10-26 01:17:07 -0700696 /* After decompression "unzipped_len" is almost certainly smaller. */
697 ret = crypto_comp_decompress(tfm, record->buf, record->size,
698 workspace, &unzipped_len);
699 if (ret) {
700 pr_err("crypto_comp_decompress failed, ret = %d!\n", ret);
701 kfree(workspace);
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800702 return;
703 }
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800704
705 /* Append ECC notice to decompressed buffer. */
Kees Cookbdabc8e2018-10-26 01:17:07 -0700706 memcpy(workspace + unzipped_len, record->buf + record->size,
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800707 record->ecc_notice_size);
708
Kees Cookbdabc8e2018-10-26 01:17:07 -0700709 /* Copy decompressed contents into an minimum-sized allocation. */
710 unzipped = kmemdup(workspace, unzipped_len + record->ecc_notice_size,
711 GFP_KERNEL);
712 kfree(workspace);
713 if (!unzipped)
714 return;
715
716 /* Swap out compressed contents with decompressed contents. */
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800717 kfree(record->buf);
Kees Cookbdabc8e2018-10-26 01:17:07 -0700718 record->buf = unzipped;
Kees Cook7e8cc8d2017-03-04 22:28:46 -0800719 record->size = unzipped_len;
720 record->compressed = false;
Kees Cook634f8f52017-03-03 17:35:25 -0800721}
722
Tony Luckca01d6d2010-12-28 14:25:21 -0800723/*
Kees Cook3a7d2fd2017-04-27 15:53:21 -0700724 * Read all the records from one persistent store backend. Create
Luck, Tony6dda9262011-08-11 15:14:39 -0700725 * files in our filesystem. Don't warn about -EEXIST errors
726 * when we are re-scanning the backing store looking to add new
727 * error records.
Tony Luckca01d6d2010-12-28 14:25:21 -0800728 */
Kees Cook3a7d2fd2017-04-27 15:53:21 -0700729void pstore_get_backend_records(struct pstore_info *psi,
730 struct dentry *root, int quiet)
Tony Luckca01d6d2010-12-28 14:25:21 -0800731{
Kees Cook2a2b0ac2017-03-04 22:57:26 -0800732 int failed = 0;
Kees Cook656de422017-05-16 12:03:31 -0700733 unsigned int stop_loop = 65536;
Tony Luckca01d6d2010-12-28 14:25:21 -0800734
Kees Cook3a7d2fd2017-04-27 15:53:21 -0700735 if (!psi || !root)
Tony Luckca01d6d2010-12-28 14:25:21 -0800736 return;
737
Kees Cookf6f82852011-11-17 12:58:07 -0800738 mutex_lock(&psi->read_mutex);
Kees Cook2174f6d2011-11-18 13:49:00 -0800739 if (psi->open && psi->open(psi))
Chen Gong06cf91b2011-05-16 11:00:27 -0700740 goto out;
741
Kees Cook1dfff7d2017-03-04 22:46:41 -0800742 /*
743 * Backend callback read() allocates record.buf. decompress_record()
744 * may reallocate record.buf. On success, pstore_mkfile() will keep
745 * the record.buf, so free it only on failure.
746 */
Kees Cook656de422017-05-16 12:03:31 -0700747 for (; stop_loop; stop_loop--) {
Kees Cook2a2b0ac2017-03-04 22:57:26 -0800748 struct pstore_record *record;
749 int rc;
750
751 record = kzalloc(sizeof(*record), GFP_KERNEL);
752 if (!record) {
753 pr_err("out of memory creating record\n");
754 break;
755 }
Kees Cooke581ca82017-05-19 15:10:31 -0700756 pstore_record_init(record, psi);
Kees Cook2a2b0ac2017-03-04 22:57:26 -0800757
758 record->size = psi->read(record);
759
760 /* No more records left in backend? */
Douglas Andersonf6525b92017-05-30 15:50:38 -0700761 if (record->size <= 0) {
762 kfree(record);
Kees Cook2a2b0ac2017-03-04 22:57:26 -0800763 break;
Douglas Andersonf6525b92017-05-30 15:50:38 -0700764 }
Kees Cook2a2b0ac2017-03-04 22:57:26 -0800765
766 decompress_record(record);
Kees Cook3a7d2fd2017-04-27 15:53:21 -0700767 rc = pstore_mkfile(root, record);
Kees Cook1dfff7d2017-03-04 22:46:41 -0800768 if (rc) {
Kees Cook83f70f02017-03-04 23:12:24 -0800769 /* pstore_mkfile() did not take record, so free it. */
Kees Cook2a2b0ac2017-03-04 22:57:26 -0800770 kfree(record->buf);
Kees Cook83f70f02017-03-04 23:12:24 -0800771 kfree(record);
Kees Cook1dfff7d2017-03-04 22:46:41 -0800772 if (rc != -EEXIST || !quiet)
773 failed++;
774 }
Tony Luckca01d6d2010-12-28 14:25:21 -0800775 }
Kees Cook2174f6d2011-11-18 13:49:00 -0800776 if (psi->close)
777 psi->close(psi);
Chen Gong06cf91b2011-05-16 11:00:27 -0700778out:
Kees Cookf6f82852011-11-17 12:58:07 -0800779 mutex_unlock(&psi->read_mutex);
Tony Luckca01d6d2010-12-28 14:25:21 -0800780
781 if (failed)
Kees Cook656de422017-05-16 12:03:31 -0700782 pr_warn("failed to create %d record(s) from '%s'\n",
Fabian Frederickef748852014-06-06 14:37:31 -0700783 failed, psi->name);
Kees Cook656de422017-05-16 12:03:31 -0700784 if (!stop_loop)
785 pr_err("looping? Too many records seen from '%s'\n",
786 psi->name);
Tony Luckca01d6d2010-12-28 14:25:21 -0800787}
788
Luck, Tony6dda9262011-08-11 15:14:39 -0700789static void pstore_dowork(struct work_struct *work)
790{
791 pstore_get_records(1);
792}
793
Kees Cook24ed9602017-08-28 11:28:21 -0700794static void pstore_timefunc(struct timer_list *unused)
Luck, Tony6dda9262011-08-11 15:14:39 -0700795{
796 if (pstore_new_entry) {
797 pstore_new_entry = 0;
798 schedule_work(&pstore_work);
799 }
800
Kees Cook78c83c82020-05-05 21:36:15 -0700801 pstore_timer_kick();
Luck, Tony6dda9262011-08-11 15:14:39 -0700802}
803
Ben Dooks (Codethink)8d82cee2019-10-16 13:33:17 +0100804static void __init pstore_choose_compression(void)
Kees Cookfe1d4752018-03-06 15:57:38 -0800805{
806 const struct pstore_zbackend *step;
807
808 if (!compress)
809 return;
810
811 for (step = zbackends; step->name; step++) {
812 if (!strcmp(compress, step->name)) {
813 zbackend = step;
Kees Cookfe1d4752018-03-06 15:57:38 -0800814 return;
815 }
816 }
817}
818
Kees Cookcb095af2018-10-18 11:17:42 -0700819static int __init pstore_init(void)
820{
821 int ret;
822
823 pstore_choose_compression();
824
Joel Fernandes (Google)41603162018-10-17 03:13:55 -0700825 /*
826 * Check if any pstore backends registered earlier but did not
827 * initialize compression because crypto was not ready. If so,
828 * initialize compression now.
829 */
Kees Cook95047b02018-10-17 14:00:12 -0700830 allocate_buf_for_compression();
Joel Fernandes (Google)41603162018-10-17 03:13:55 -0700831
Kees Cookcb095af2018-10-18 11:17:42 -0700832 ret = pstore_init_fs();
833 if (ret)
chenqiwu8a57d6d2020-02-07 17:46:39 +0800834 free_buf_for_compression();
Kees Cookcb095af2018-10-18 11:17:42 -0700835
chenqiwu8a57d6d2020-02-07 17:46:39 +0800836 return ret;
Kees Cookcb095af2018-10-18 11:17:42 -0700837}
Joel Fernandes (Google)41603162018-10-17 03:13:55 -0700838late_initcall(pstore_init);
Kees Cookcb095af2018-10-18 11:17:42 -0700839
840static void __exit pstore_exit(void)
841{
842 pstore_exit_fs();
843}
844module_exit(pstore_exit)
845
Kees Cookcb095af2018-10-18 11:17:42 -0700846MODULE_AUTHOR("Tony Luck <tony.luck@intel.com>");
847MODULE_LICENSE("GPL");