Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Persistent Storage - platform driver interface parts. |
| 3 | * |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 4 | * Copyright (C) 2007-2008 Google, Inc. |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 5 | * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 21 | #define pr_fmt(fmt) "pstore: " fmt |
| 22 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 23 | #include <linux/atomic.h> |
| 24 | #include <linux/types.h> |
| 25 | #include <linux/errno.h> |
| 26 | #include <linux/init.h> |
| 27 | #include <linux/kmsg_dump.h> |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 28 | #include <linux/console.h> |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 29 | #include <linux/module.h> |
| 30 | #include <linux/pstore.h> |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 31 | #include <linux/zlib.h> |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 32 | #include <linux/string.h> |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 33 | #include <linux/timer.h> |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 34 | #include <linux/slab.h> |
| 35 | #include <linux/uaccess.h> |
Don Zickus | abd4d55 | 2011-08-12 10:54:51 -0700 | [diff] [blame] | 36 | #include <linux/hardirq.h> |
Anton Vorontsov | a3f5f07 | 2012-05-26 06:20:28 -0700 | [diff] [blame] | 37 | #include <linux/jiffies.h> |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 38 | #include <linux/workqueue.h> |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 39 | |
| 40 | #include "internal.h" |
| 41 | |
| 42 | /* |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 43 | * We defer making "oops" entries appear in pstore - see |
| 44 | * whether the system is actually still running well enough |
| 45 | * to let someone see the entry |
| 46 | */ |
Anton Vorontsov | 521f7288 | 2012-05-26 06:20:29 -0700 | [diff] [blame] | 47 | static int pstore_update_ms = -1; |
Anton Vorontsov | a3f5f07 | 2012-05-26 06:20:28 -0700 | [diff] [blame] | 48 | module_param_named(update_ms, pstore_update_ms, int, 0600); |
| 49 | MODULE_PARM_DESC(update_ms, "milliseconds before pstore updates its content " |
Anton Vorontsov | 521f7288 | 2012-05-26 06:20:29 -0700 | [diff] [blame] | 50 | "(default is -1, which means runtime updates are disabled; " |
| 51 | "enabling this option is not safe, it may lead to further " |
| 52 | "corruption on Oopses)"); |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 53 | |
| 54 | static int pstore_new_entry; |
| 55 | |
| 56 | static void pstore_timefunc(unsigned long); |
| 57 | static DEFINE_TIMER(pstore_timer, pstore_timefunc, 0, 0); |
| 58 | |
| 59 | static void pstore_dowork(struct work_struct *); |
| 60 | static DECLARE_WORK(pstore_work, pstore_dowork); |
| 61 | |
| 62 | /* |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 63 | * pstore_lock just protects "psinfo" during |
| 64 | * calls to pstore_register() |
| 65 | */ |
| 66 | static DEFINE_SPINLOCK(pstore_lock); |
Anton Vorontsov | 060287b | 2012-07-09 17:10:41 -0700 | [diff] [blame] | 67 | struct pstore_info *psinfo; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 68 | |
Matthew Garrett | dee28e7 | 2011-07-21 16:57:55 -0400 | [diff] [blame] | 69 | static char *backend; |
| 70 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 71 | /* Compression parameters */ |
| 72 | #define COMPR_LEVEL 6 |
| 73 | #define WINDOW_BITS 12 |
| 74 | #define MEM_LEVEL 4 |
| 75 | static struct z_stream_s stream; |
| 76 | |
| 77 | static char *big_oops_buf; |
| 78 | static size_t big_oops_buf_sz; |
| 79 | |
Luck, Tony | 366f7e7 | 2011-03-18 15:33:43 -0700 | [diff] [blame] | 80 | /* How much of the console log to snapshot */ |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 81 | static unsigned long kmsg_bytes = 10240; |
| 82 | |
Luck, Tony | 366f7e7 | 2011-03-18 15:33:43 -0700 | [diff] [blame] | 83 | void pstore_set_kmsg_bytes(int bytes) |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 84 | { |
Luck, Tony | 366f7e7 | 2011-03-18 15:33:43 -0700 | [diff] [blame] | 85 | kmsg_bytes = bytes; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 86 | } |
| 87 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 88 | /* Tag each group of saved records with a sequence number */ |
| 89 | static int oopscount; |
| 90 | |
Seiji Aguchi | 381b872 | 2012-03-16 15:36:59 -0700 | [diff] [blame] | 91 | static const char *get_reason_str(enum kmsg_dump_reason reason) |
| 92 | { |
| 93 | switch (reason) { |
| 94 | case KMSG_DUMP_PANIC: |
| 95 | return "Panic"; |
| 96 | case KMSG_DUMP_OOPS: |
| 97 | return "Oops"; |
| 98 | case KMSG_DUMP_EMERG: |
| 99 | return "Emergency"; |
| 100 | case KMSG_DUMP_RESTART: |
| 101 | return "Restart"; |
| 102 | case KMSG_DUMP_HALT: |
| 103 | return "Halt"; |
| 104 | case KMSG_DUMP_POWEROFF: |
| 105 | return "Poweroff"; |
| 106 | default: |
| 107 | return "Unknown"; |
| 108 | } |
| 109 | } |
Tony Luck | 9f6af27 | 2011-03-22 16:01:49 -0700 | [diff] [blame] | 110 | |
Seiji Aguchi | 9f244e9 | 2013-01-11 18:09:41 +0000 | [diff] [blame] | 111 | bool pstore_cannot_block_path(enum kmsg_dump_reason reason) |
| 112 | { |
| 113 | /* |
| 114 | * In case of NMI path, pstore shouldn't be blocked |
| 115 | * regardless of reason. |
| 116 | */ |
| 117 | if (in_nmi()) |
| 118 | return true; |
| 119 | |
| 120 | switch (reason) { |
| 121 | /* In panic case, other cpus are stopped by smp_send_stop(). */ |
| 122 | case KMSG_DUMP_PANIC: |
| 123 | /* Emergency restart shouldn't be blocked by spin lock. */ |
| 124 | case KMSG_DUMP_EMERG: |
| 125 | return true; |
| 126 | default: |
| 127 | return false; |
| 128 | } |
| 129 | } |
| 130 | EXPORT_SYMBOL_GPL(pstore_cannot_block_path); |
| 131 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 132 | /* Derived from logfs_compress() */ |
| 133 | static int pstore_compress(const void *in, void *out, size_t inlen, |
| 134 | size_t outlen) |
| 135 | { |
| 136 | int err, ret; |
| 137 | |
| 138 | ret = -EIO; |
| 139 | err = zlib_deflateInit2(&stream, COMPR_LEVEL, Z_DEFLATED, WINDOW_BITS, |
| 140 | MEM_LEVEL, Z_DEFAULT_STRATEGY); |
| 141 | if (err != Z_OK) |
| 142 | goto error; |
| 143 | |
| 144 | stream.next_in = in; |
| 145 | stream.avail_in = inlen; |
| 146 | stream.total_in = 0; |
| 147 | stream.next_out = out; |
| 148 | stream.avail_out = outlen; |
| 149 | stream.total_out = 0; |
| 150 | |
| 151 | err = zlib_deflate(&stream, Z_FINISH); |
| 152 | if (err != Z_STREAM_END) |
| 153 | goto error; |
| 154 | |
| 155 | err = zlib_deflateEnd(&stream); |
| 156 | if (err != Z_OK) |
| 157 | goto error; |
| 158 | |
| 159 | if (stream.total_out >= stream.total_in) |
| 160 | goto error; |
| 161 | |
| 162 | ret = stream.total_out; |
| 163 | error: |
| 164 | return ret; |
| 165 | } |
| 166 | |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 167 | /* Derived from logfs_uncompress */ |
| 168 | static int pstore_decompress(void *in, void *out, size_t inlen, size_t outlen) |
| 169 | { |
| 170 | int err, ret; |
| 171 | |
| 172 | ret = -EIO; |
Aruna Balakrishnaiah | b61edf8 | 2013-09-11 10:58:03 -0700 | [diff] [blame] | 173 | err = zlib_inflateInit2(&stream, WINDOW_BITS); |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 174 | if (err != Z_OK) |
| 175 | goto error; |
| 176 | |
| 177 | stream.next_in = in; |
| 178 | stream.avail_in = inlen; |
| 179 | stream.total_in = 0; |
| 180 | stream.next_out = out; |
| 181 | stream.avail_out = outlen; |
| 182 | stream.total_out = 0; |
| 183 | |
| 184 | err = zlib_inflate(&stream, Z_FINISH); |
| 185 | if (err != Z_STREAM_END) |
| 186 | goto error; |
| 187 | |
| 188 | err = zlib_inflateEnd(&stream); |
| 189 | if (err != Z_OK) |
| 190 | goto error; |
| 191 | |
| 192 | ret = stream.total_out; |
| 193 | error: |
| 194 | return ret; |
| 195 | } |
| 196 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 197 | static void allocate_buf_for_compression(void) |
| 198 | { |
| 199 | size_t size; |
Aruna Balakrishnaiah | 7de8fe2 | 2013-09-11 10:57:41 -0700 | [diff] [blame] | 200 | size_t cmpr; |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 201 | |
Aruna Balakrishnaiah | 7de8fe2 | 2013-09-11 10:57:41 -0700 | [diff] [blame] | 202 | switch (psinfo->bufsize) { |
| 203 | /* buffer range for efivars */ |
| 204 | case 1000 ... 2000: |
| 205 | cmpr = 56; |
| 206 | break; |
| 207 | case 2001 ... 3000: |
| 208 | cmpr = 54; |
| 209 | break; |
| 210 | case 3001 ... 3999: |
| 211 | cmpr = 52; |
| 212 | break; |
| 213 | /* buffer range for nvram, erst */ |
| 214 | case 4000 ... 10000: |
| 215 | cmpr = 45; |
| 216 | break; |
| 217 | default: |
| 218 | cmpr = 60; |
| 219 | break; |
| 220 | } |
| 221 | |
| 222 | big_oops_buf_sz = (psinfo->bufsize * 100) / cmpr; |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 223 | big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL); |
| 224 | if (big_oops_buf) { |
| 225 | size = max(zlib_deflate_workspacesize(WINDOW_BITS, MEM_LEVEL), |
| 226 | zlib_inflate_workspacesize()); |
| 227 | stream.workspace = kmalloc(size, GFP_KERNEL); |
| 228 | if (!stream.workspace) { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 229 | pr_err("No memory for compression workspace; skipping compression\n"); |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 230 | kfree(big_oops_buf); |
| 231 | big_oops_buf = NULL; |
| 232 | } |
| 233 | } else { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 234 | pr_err("No memory for uncompressed data; skipping compression\n"); |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 235 | stream.workspace = NULL; |
| 236 | } |
| 237 | |
| 238 | } |
| 239 | |
Geliang Tang | ee1d267 | 2015-10-20 00:39:03 -0700 | [diff] [blame^] | 240 | static void free_buf_for_compression(void) |
| 241 | { |
| 242 | kfree(stream.workspace); |
| 243 | stream.workspace = NULL; |
| 244 | kfree(big_oops_buf); |
| 245 | big_oops_buf = NULL; |
| 246 | } |
| 247 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 248 | /* |
| 249 | * Called when compression fails, since the printk buffer |
| 250 | * would be fetched for compression calling it again when |
| 251 | * compression fails would have moved the iterator of |
| 252 | * printk buffer which results in fetching old contents. |
| 253 | * Copy the recent messages from big_oops_buf to psinfo->buf |
| 254 | */ |
| 255 | static size_t copy_kmsg_to_buffer(int hsize, size_t len) |
| 256 | { |
| 257 | size_t total_len; |
| 258 | size_t diff; |
| 259 | |
| 260 | total_len = hsize + len; |
| 261 | |
| 262 | if (total_len > psinfo->bufsize) { |
| 263 | diff = total_len - psinfo->bufsize + hsize; |
| 264 | memcpy(psinfo->buf, big_oops_buf, hsize); |
| 265 | memcpy(psinfo->buf + hsize, big_oops_buf + diff, |
| 266 | psinfo->bufsize - hsize); |
| 267 | total_len = psinfo->bufsize; |
| 268 | } else |
| 269 | memcpy(psinfo->buf, big_oops_buf, total_len); |
| 270 | |
| 271 | return total_len; |
| 272 | } |
| 273 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 274 | /* |
| 275 | * callback from kmsg_dump. (s2,l2) has the most recently |
| 276 | * written bytes, older bytes are in (s1,l1). Save as much |
| 277 | * as we can from the end of the buffer. |
| 278 | */ |
| 279 | static void pstore_dump(struct kmsg_dumper *dumper, |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 280 | enum kmsg_dump_reason reason) |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 281 | { |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 282 | unsigned long total = 0; |
Seiji Aguchi | 381b872 | 2012-03-16 15:36:59 -0700 | [diff] [blame] | 283 | const char *why; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 284 | u64 id; |
Matthew Garrett | b94fdd0 | 2011-07-21 16:57:54 -0400 | [diff] [blame] | 285 | unsigned int part = 1; |
Don Zickus | abd4d55 | 2011-08-12 10:54:51 -0700 | [diff] [blame] | 286 | unsigned long flags = 0; |
| 287 | int is_locked = 0; |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 288 | int ret; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 289 | |
Seiji Aguchi | 381b872 | 2012-03-16 15:36:59 -0700 | [diff] [blame] | 290 | why = get_reason_str(reason); |
Tony Luck | 9f6af27 | 2011-03-22 16:01:49 -0700 | [diff] [blame] | 291 | |
Seiji Aguchi | 9f244e9 | 2013-01-11 18:09:41 +0000 | [diff] [blame] | 292 | if (pstore_cannot_block_path(reason)) { |
| 293 | is_locked = spin_trylock_irqsave(&psinfo->buf_lock, flags); |
| 294 | if (!is_locked) { |
| 295 | pr_err("pstore dump routine blocked in %s path, may corrupt error record\n" |
| 296 | , in_nmi() ? "NMI" : why); |
| 297 | } |
Don Zickus | abd4d55 | 2011-08-12 10:54:51 -0700 | [diff] [blame] | 298 | } else |
| 299 | spin_lock_irqsave(&psinfo->buf_lock, flags); |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 300 | oopscount++; |
| 301 | while (total < kmsg_bytes) { |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 302 | char *dst; |
| 303 | unsigned long size; |
| 304 | int hsize; |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 305 | int zipped_len = -1; |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 306 | size_t len; |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 307 | bool compressed; |
| 308 | size_t total_len; |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 309 | |
Konstantin Khlebnikov | f0e2efc | 2015-05-21 09:26:19 -0700 | [diff] [blame] | 310 | if (big_oops_buf && is_locked) { |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 311 | dst = big_oops_buf; |
alex chen | a6b8978 | 2015-01-16 15:52:03 -0800 | [diff] [blame] | 312 | hsize = sprintf(dst, "%s#%d Part%u\n", why, |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 313 | oopscount, part); |
| 314 | size = big_oops_buf_sz - hsize; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 315 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 316 | if (!kmsg_dump_get_buffer(dumper, true, dst + hsize, |
| 317 | size, &len)) |
| 318 | break; |
| 319 | |
| 320 | zipped_len = pstore_compress(dst, psinfo->buf, |
| 321 | hsize + len, psinfo->bufsize); |
| 322 | |
| 323 | if (zipped_len > 0) { |
| 324 | compressed = true; |
| 325 | total_len = zipped_len; |
| 326 | } else { |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 327 | compressed = false; |
| 328 | total_len = copy_kmsg_to_buffer(hsize, len); |
| 329 | } |
| 330 | } else { |
| 331 | dst = psinfo->buf; |
alex chen | a6b8978 | 2015-01-16 15:52:03 -0800 | [diff] [blame] | 332 | hsize = sprintf(dst, "%s#%d Part%u\n", why, oopscount, |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 333 | part); |
| 334 | size = psinfo->bufsize - hsize; |
| 335 | dst += hsize; |
| 336 | |
| 337 | if (!kmsg_dump_get_buffer(dumper, true, dst, |
| 338 | size, &len)) |
| 339 | break; |
| 340 | |
| 341 | compressed = false; |
| 342 | total_len = hsize + len; |
| 343 | } |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 344 | |
Kees Cook | 3d6d8d2 | 2011-11-17 13:13:29 -0800 | [diff] [blame] | 345 | ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part, |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 346 | oopscount, compressed, total_len, psinfo); |
Chen Gong | b238b8f | 2011-10-12 09:17:24 -0700 | [diff] [blame] | 347 | if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted()) |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 348 | pstore_new_entry = 1; |
Kay Sievers | e2ae715 | 2012-06-15 14:07:51 +0200 | [diff] [blame] | 349 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 350 | total += total_len; |
Matthew Garrett | 5628068 | 2011-07-21 16:57:53 -0400 | [diff] [blame] | 351 | part++; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 352 | } |
Seiji Aguchi | 9f244e9 | 2013-01-11 18:09:41 +0000 | [diff] [blame] | 353 | if (pstore_cannot_block_path(reason)) { |
Don Zickus | abd4d55 | 2011-08-12 10:54:51 -0700 | [diff] [blame] | 354 | if (is_locked) |
Seiji Aguchi | 9f244e9 | 2013-01-11 18:09:41 +0000 | [diff] [blame] | 355 | spin_unlock_irqrestore(&psinfo->buf_lock, flags); |
Don Zickus | abd4d55 | 2011-08-12 10:54:51 -0700 | [diff] [blame] | 356 | } else |
| 357 | spin_unlock_irqrestore(&psinfo->buf_lock, flags); |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 358 | } |
| 359 | |
| 360 | static struct kmsg_dumper pstore_dumper = { |
| 361 | .dump = pstore_dump, |
| 362 | }; |
| 363 | |
Geliang Tang | 1873041 | 2015-10-20 00:39:02 -0700 | [diff] [blame] | 364 | static void pstore_register_kmsg(void) |
| 365 | { |
| 366 | kmsg_dump_register(&pstore_dumper); |
| 367 | } |
| 368 | |
Geliang Tang | ee1d267 | 2015-10-20 00:39:03 -0700 | [diff] [blame^] | 369 | static void pstore_unregister_kmsg(void) |
| 370 | { |
| 371 | kmsg_dump_unregister(&pstore_dumper); |
| 372 | } |
| 373 | |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 374 | #ifdef CONFIG_PSTORE_CONSOLE |
| 375 | static void pstore_console_write(struct console *con, const char *s, unsigned c) |
| 376 | { |
| 377 | const char *e = s + c; |
| 378 | |
| 379 | while (s < e) { |
| 380 | unsigned long flags; |
Colin Ian King | 70a6f46 | 2012-11-14 11:49:53 +0000 | [diff] [blame] | 381 | u64 id; |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 382 | |
| 383 | if (c > psinfo->bufsize) |
| 384 | c = psinfo->bufsize; |
Chuansheng Liu | 80c9d03 | 2012-09-18 01:43:44 +0800 | [diff] [blame] | 385 | |
| 386 | if (oops_in_progress) { |
| 387 | if (!spin_trylock_irqsave(&psinfo->buf_lock, flags)) |
| 388 | break; |
| 389 | } else { |
| 390 | spin_lock_irqsave(&psinfo->buf_lock, flags); |
| 391 | } |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 392 | memcpy(psinfo->buf, s, c); |
Aruna Balakrishnaiah | 6bbbca7 | 2013-06-27 14:02:56 +0530 | [diff] [blame] | 393 | psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, 0, 0, c, psinfo); |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 394 | spin_unlock_irqrestore(&psinfo->buf_lock, flags); |
| 395 | s += c; |
| 396 | c = e - s; |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | static struct console pstore_console = { |
| 401 | .name = "pstore", |
| 402 | .write = pstore_console_write, |
| 403 | .flags = CON_PRINTBUFFER | CON_ENABLED | CON_ANYTIME, |
| 404 | .index = -1, |
| 405 | }; |
| 406 | |
| 407 | static void pstore_register_console(void) |
| 408 | { |
| 409 | register_console(&pstore_console); |
| 410 | } |
Geliang Tang | ee1d267 | 2015-10-20 00:39:03 -0700 | [diff] [blame^] | 411 | |
| 412 | static void pstore_unregister_console(void) |
| 413 | { |
| 414 | unregister_console(&pstore_console); |
| 415 | } |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 416 | #else |
| 417 | static void pstore_register_console(void) {} |
Geliang Tang | ee1d267 | 2015-10-20 00:39:03 -0700 | [diff] [blame^] | 418 | static void pstore_unregister_console(void) {} |
Anton Vorontsov | f29e595 | 2012-05-26 06:20:19 -0700 | [diff] [blame] | 419 | #endif |
| 420 | |
Anton Vorontsov | 897dba0 | 2012-07-09 17:10:40 -0700 | [diff] [blame] | 421 | static int pstore_write_compat(enum pstore_type_id type, |
| 422 | enum kmsg_dump_reason reason, |
Seiji Aguchi | 755d4fe | 2012-11-26 16:07:44 -0800 | [diff] [blame] | 423 | u64 *id, unsigned int part, int count, |
Aruna Balakrishnaiah | b3b515b | 2013-08-16 13:52:47 -0700 | [diff] [blame] | 424 | bool compressed, size_t size, |
Aruna Balakrishnaiah | 6bbbca7 | 2013-06-27 14:02:56 +0530 | [diff] [blame] | 425 | struct pstore_info *psi) |
Anton Vorontsov | 897dba0 | 2012-07-09 17:10:40 -0700 | [diff] [blame] | 426 | { |
Aruna Balakrishnaiah | b3b515b | 2013-08-16 13:52:47 -0700 | [diff] [blame] | 427 | return psi->write_buf(type, reason, id, part, psinfo->buf, compressed, |
Aruna Balakrishnaiah | 6bbbca7 | 2013-06-27 14:02:56 +0530 | [diff] [blame] | 428 | size, psi); |
Anton Vorontsov | 897dba0 | 2012-07-09 17:10:40 -0700 | [diff] [blame] | 429 | } |
| 430 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 431 | /* |
| 432 | * platform specific persistent storage driver registers with |
| 433 | * us here. If pstore is already mounted, call the platform |
| 434 | * read function right away to populate the file system. If not |
| 435 | * then the pstore mount code will call us later to fill out |
| 436 | * the file system. |
| 437 | * |
| 438 | * Register with kmsg_dump to save last part of console log on panic. |
| 439 | */ |
| 440 | int pstore_register(struct pstore_info *psi) |
| 441 | { |
| 442 | struct module *owner = psi->owner; |
| 443 | |
Lenny Szubowicz | 8e48b1a | 2013-06-28 17:11:33 -0400 | [diff] [blame] | 444 | if (backend && strcmp(backend, psi->name)) |
| 445 | return -EPERM; |
| 446 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 447 | spin_lock(&pstore_lock); |
| 448 | if (psinfo) { |
| 449 | spin_unlock(&pstore_lock); |
| 450 | return -EBUSY; |
| 451 | } |
Matthew Garrett | dee28e7 | 2011-07-21 16:57:55 -0400 | [diff] [blame] | 452 | |
Anton Vorontsov | 897dba0 | 2012-07-09 17:10:40 -0700 | [diff] [blame] | 453 | if (!psi->write) |
| 454 | psi->write = pstore_write_compat; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 455 | psinfo = psi; |
Kees Cook | f6f8285 | 2011-11-17 12:58:07 -0800 | [diff] [blame] | 456 | mutex_init(&psinfo->read_mutex); |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 457 | spin_unlock(&pstore_lock); |
| 458 | |
| 459 | if (owner && !try_module_get(owner)) { |
| 460 | psinfo = NULL; |
| 461 | return -EINVAL; |
| 462 | } |
| 463 | |
Aruna Balakrishnaiah | b0aad7a | 2013-08-16 13:53:10 -0700 | [diff] [blame] | 464 | allocate_buf_for_compression(); |
| 465 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 466 | if (pstore_is_mounted()) |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 467 | pstore_get_records(0); |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 468 | |
Geliang Tang | 1873041 | 2015-10-20 00:39:02 -0700 | [diff] [blame] | 469 | pstore_register_kmsg(); |
Luck, Tony | df36ac1 | 2013-12-18 15:17:10 -0800 | [diff] [blame] | 470 | |
| 471 | if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) { |
| 472 | pstore_register_console(); |
| 473 | pstore_register_ftrace(); |
Mark Salyzyn | 9d5438f | 2015-01-16 16:01:10 -0800 | [diff] [blame] | 474 | pstore_register_pmsg(); |
Luck, Tony | df36ac1 | 2013-12-18 15:17:10 -0800 | [diff] [blame] | 475 | } |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 476 | |
Anton Vorontsov | a3f5f07 | 2012-05-26 06:20:28 -0700 | [diff] [blame] | 477 | if (pstore_update_ms >= 0) { |
| 478 | pstore_timer.expires = jiffies + |
| 479 | msecs_to_jiffies(pstore_update_ms); |
| 480 | add_timer(&pstore_timer); |
| 481 | } |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 482 | |
Wang Long | 42222c2 | 2015-05-21 09:34:22 -0700 | [diff] [blame] | 483 | /* |
| 484 | * Update the module parameter backend, so it is visible |
| 485 | * through /sys/module/pstore/parameters/backend |
| 486 | */ |
| 487 | backend = psi->name; |
| 488 | |
Geliang Tang | ee1d267 | 2015-10-20 00:39:03 -0700 | [diff] [blame^] | 489 | module_put(owner); |
| 490 | |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 491 | pr_info("Registered %s as persistent store backend\n", psi->name); |
Lenny Szubowicz | 8e48b1a | 2013-06-28 17:11:33 -0400 | [diff] [blame] | 492 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 493 | return 0; |
| 494 | } |
| 495 | EXPORT_SYMBOL_GPL(pstore_register); |
| 496 | |
Geliang Tang | ee1d267 | 2015-10-20 00:39:03 -0700 | [diff] [blame^] | 497 | void pstore_unregister(struct pstore_info *psi) |
| 498 | { |
| 499 | pstore_unregister_pmsg(); |
| 500 | pstore_unregister_ftrace(); |
| 501 | pstore_unregister_console(); |
| 502 | pstore_unregister_kmsg(); |
| 503 | |
| 504 | free_buf_for_compression(); |
| 505 | |
| 506 | psinfo = NULL; |
| 507 | backend = NULL; |
| 508 | } |
| 509 | EXPORT_SYMBOL_GPL(pstore_unregister); |
| 510 | |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 511 | /* |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 512 | * Read all the records from the persistent store. Create |
| 513 | * files in our filesystem. Don't warn about -EEXIST errors |
| 514 | * when we are re-scanning the backing store looking to add new |
| 515 | * error records. |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 516 | */ |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 517 | void pstore_get_records(int quiet) |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 518 | { |
| 519 | struct pstore_info *psi = psinfo; |
Kees Cook | f6f8285 | 2011-11-17 12:58:07 -0800 | [diff] [blame] | 520 | char *buf = NULL; |
Chen Gong | 8d38d74 | 2011-05-16 10:58:57 -0700 | [diff] [blame] | 521 | ssize_t size; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 522 | u64 id; |
Seiji Aguchi | 755d4fe | 2012-11-26 16:07:44 -0800 | [diff] [blame] | 523 | int count; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 524 | enum pstore_type_id type; |
| 525 | struct timespec time; |
Chen Gong | 06cf91b | 2011-05-16 11:00:27 -0700 | [diff] [blame] | 526 | int failed = 0, rc; |
Aruna Balakrishnaiah | 9a4e139 | 2013-08-16 13:53:19 -0700 | [diff] [blame] | 527 | bool compressed; |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 528 | int unzipped_len = -1; |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 529 | |
| 530 | if (!psi) |
| 531 | return; |
| 532 | |
Kees Cook | f6f8285 | 2011-11-17 12:58:07 -0800 | [diff] [blame] | 533 | mutex_lock(&psi->read_mutex); |
Kees Cook | 2174f6d | 2011-11-18 13:49:00 -0800 | [diff] [blame] | 534 | if (psi->open && psi->open(psi)) |
Chen Gong | 06cf91b | 2011-05-16 11:00:27 -0700 | [diff] [blame] | 535 | goto out; |
| 536 | |
Aruna Balakrishnaiah | 9a4e139 | 2013-08-16 13:53:19 -0700 | [diff] [blame] | 537 | while ((size = psi->read(&id, &type, &count, &time, &buf, &compressed, |
| 538 | psi)) > 0) { |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 539 | if (compressed && (type == PSTORE_TYPE_DMESG)) { |
| 540 | if (big_oops_buf) |
| 541 | unzipped_len = pstore_decompress(buf, |
| 542 | big_oops_buf, size, |
| 543 | big_oops_buf_sz); |
| 544 | |
| 545 | if (unzipped_len > 0) { |
Liu ShuoX | e32634f | 2014-03-12 21:34:06 +0800 | [diff] [blame] | 546 | kfree(buf); |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 547 | buf = big_oops_buf; |
| 548 | size = unzipped_len; |
Aruna Balakrishnaiah | 9ad2cbe | 2013-08-16 13:53:39 -0700 | [diff] [blame] | 549 | compressed = false; |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 550 | } else { |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 551 | pr_err("decompression failed;returned %d\n", |
| 552 | unzipped_len); |
Aruna Balakrishnaiah | 9ad2cbe | 2013-08-16 13:53:39 -0700 | [diff] [blame] | 553 | compressed = true; |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 554 | } |
| 555 | } |
Seiji Aguchi | 755d4fe | 2012-11-26 16:07:44 -0800 | [diff] [blame] | 556 | rc = pstore_mkfile(type, psi->name, id, count, buf, |
Aruna Balakrishnaiah | 9ad2cbe | 2013-08-16 13:53:39 -0700 | [diff] [blame] | 557 | compressed, (size_t)size, time, psi); |
Aruna Balakrishnaiah | adb42f5 | 2013-08-16 13:53:28 -0700 | [diff] [blame] | 558 | if (unzipped_len < 0) { |
| 559 | /* Free buffer other than big oops */ |
| 560 | kfree(buf); |
| 561 | buf = NULL; |
| 562 | } else |
| 563 | unzipped_len = -1; |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 564 | if (rc && (rc != -EEXIST || !quiet)) |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 565 | failed++; |
| 566 | } |
Kees Cook | 2174f6d | 2011-11-18 13:49:00 -0800 | [diff] [blame] | 567 | if (psi->close) |
| 568 | psi->close(psi); |
Chen Gong | 06cf91b | 2011-05-16 11:00:27 -0700 | [diff] [blame] | 569 | out: |
Kees Cook | f6f8285 | 2011-11-17 12:58:07 -0800 | [diff] [blame] | 570 | mutex_unlock(&psi->read_mutex); |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 571 | |
| 572 | if (failed) |
Fabian Frederick | ef74885 | 2014-06-06 14:37:31 -0700 | [diff] [blame] | 573 | pr_warn("failed to load %d record(s) from '%s'\n", |
| 574 | failed, psi->name); |
Tony Luck | ca01d6d | 2010-12-28 14:25:21 -0800 | [diff] [blame] | 575 | } |
| 576 | |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 577 | static void pstore_dowork(struct work_struct *work) |
| 578 | { |
| 579 | pstore_get_records(1); |
| 580 | } |
| 581 | |
| 582 | static void pstore_timefunc(unsigned long dummy) |
| 583 | { |
| 584 | if (pstore_new_entry) { |
| 585 | pstore_new_entry = 0; |
| 586 | schedule_work(&pstore_work); |
| 587 | } |
| 588 | |
Anton Vorontsov | a3f5f07 | 2012-05-26 06:20:28 -0700 | [diff] [blame] | 589 | mod_timer(&pstore_timer, jiffies + msecs_to_jiffies(pstore_update_ms)); |
Luck, Tony | 6dda926 | 2011-08-11 15:14:39 -0700 | [diff] [blame] | 590 | } |
| 591 | |
Matthew Garrett | dee28e7 | 2011-07-21 16:57:55 -0400 | [diff] [blame] | 592 | module_param(backend, charp, 0444); |
| 593 | MODULE_PARM_DESC(backend, "Pstore backend to use"); |