blob: 974218009b282575b53392af6c529d93e474755d [file] [log] [blame]
Andrew Jeffery4fe996c2018-02-27 12:16:48 +10301// SPDX-License-Identifier: Apache-2.0
2// Copyright (C) 2018 IBM Corp.
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +11003
4#define _GNU_SOURCE
5#include <assert.h>
6#include <errno.h>
7#include <fcntl.h>
8#include <getopt.h>
9#include <limits.h>
10#include <poll.h>
11#include <stdbool.h>
12#include <stdint.h>
13#include <stdio.h>
14#include <stdlib.h>
15#include <string.h>
16#include <syslog.h>
17#include <signal.h>
18#include <sys/ioctl.h>
19#include <sys/mman.h>
20#include <sys/stat.h>
21#include <sys/timerfd.h>
22#include <sys/types.h>
23#include <time.h>
24#include <unistd.h>
25#include <inttypes.h>
26#include <mtd/mtd-abi.h>
27
28#include "mbox.h"
29#include "common.h"
30#include "mboxd_msg.h"
31#include "mboxd_windows.h"
32#include "mboxd_flash.h"
33
34/* Initialisation Functions */
35
36/*
37 * init_window_state() - Initialise a new window to a known state
38 * @window: The window to initialise
39 * @size: The size of the window
40 */
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100041static void init_window_state(struct window_context *window, uint32_t size)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110042{
43 window->mem = NULL;
44 window->flash_offset = FLASH_OFFSET_UNINIT;
45 window->size = size;
46 window->dirty_bmap = NULL;
47 window->age = 0;
48}
49
50/*
51 * init_window_mem() - Divide the reserved memory region among the windows
52 * @context: The mbox context pointer
53 *
54 * Return: 0 on success otherwise negative error code
55 */
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100056static int init_window_mem(struct mbox_context *context)
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110057{
58 void *mem_location = context->mem;
59 int i;
60
61 /*
62 * Carve up the reserved memory region and allocate it to each of the
63 * windows. The windows are placed one after the other in ascending
64 * order, so the first window will be first in memory and so on. We
65 * shouldn't have allocated more windows than we have memory, but if we
66 * did we will error out here
67 */
68 for (i = 0; i < context->windows.num; i++) {
Suraj Jitindar Singh28519592017-04-27 14:48:58 +100069 uint32_t size = context->windows.window[i].size;
70 MSG_DBG("Window %d @ %p for size 0x%.8x\n", i,
71 mem_location, size);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110072 context->windows.window[i].mem = mem_location;
Suraj Jitindar Singh28519592017-04-27 14:48:58 +100073 mem_location += size;
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +110074 if (mem_location > (context->mem + context->mem_size)) {
75 /* Tried to allocate window past the end of memory */
76 MSG_ERR("Total size of windows exceeds reserved mem\n");
77 MSG_ERR("Try smaller or fewer windows\n");
78 MSG_ERR("Mem size: 0x%.8x\n", context->mem_size);
79 return -1;
80 }
81 }
82
83 return 0;
84}
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +100085/*
86 * init_windows() - Initalise the window cache
87 * @context: The mbox context pointer
88 *
89 * Return: 0 on success otherwise negative
90 */
91int init_windows(struct mbox_context *context)
92{
93 int i;
94
95 /* Check if window size and number set - otherwise set to default */
96 if (!context->windows.default_size) {
97 /* Default to 1MB windows */
98 context->windows.default_size = 1 << 20;
99 }
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000100 MSG_INFO("Window size: 0x%.8x\n", context->windows.default_size);
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +1000101 if (!context->windows.num) {
102 /* Use the entire reserved memory region by default */
103 context->windows.num = context->mem_size /
104 context->windows.default_size;
105 }
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000106 MSG_INFO("Number of windows: %d\n", context->windows.num);
Suraj Jitindar Singhc29172e2017-04-12 14:26:47 +1000107
108 context->windows.window = calloc(context->windows.num,
109 sizeof(*context->windows.window));
110 if (!context->windows.window) {
111 MSG_ERR("Memory allocation failed\n");
112 return -1;
113 }
114
115 for (i = 0; i < context->windows.num; i++) {
116 init_window_state(&context->windows.window[i],
117 context->windows.default_size);
118 }
119
120 return init_window_mem(context);
121}
122
123/*
124 * free_windows() - Free the window cache
125 * @context: The mbox context pointer
126 */
127void free_windows(struct mbox_context *context)
128{
129 int i;
130
131 /* Check window cache has actually been allocated */
132 if (context->windows.window) {
133 for (i = 0; i < context->windows.num; i++) {
134 free(context->windows.window[i].dirty_bmap);
135 }
136 free(context->windows.window);
137 }
138}
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100139
140/* Write from Window Functions */
141
142/*
143 * write_from_window_v1() - Handle writing when erase and block size differ
144 * @context: The mbox context pointer
145 * @offset_bytes: The offset in the current window to write from (bytes)
146 * @count_bytes: Number of bytes to write
147 *
148 * Handle a write_from_window for dirty memory when block_size is less than the
149 * flash erase size
150 * This requires us to be a bit careful because we might have to erase more
151 * than we want to write which could result in data loss if we don't have the
152 * entire portion of flash to be erased already saved in memory (for us to
153 * write back after the erase)
154 *
155 * Return: 0 on success otherwise negative error code
156 */
157int write_from_window_v1(struct mbox_context *context,
158 uint32_t offset_bytes, uint32_t count_bytes)
159{
160 int rc;
161 uint32_t flash_offset;
162 struct window_context low_mem = { 0 }, high_mem = { 0 };
163
164 /* Find where in phys flash this is based on the window.flash_offset */
165 flash_offset = context->current->flash_offset + offset_bytes;
166
167 /*
168 * low_mem.flash_offset = erase boundary below where we're writing
169 * low_mem.size = size from low_mem.flash_offset to where we're writing
170 *
171 * high_mem.flash_offset = end of where we're writing
172 * high_mem.size = size from end of where we're writing to next erase
173 * boundary
174 */
175 low_mem.flash_offset = align_down(flash_offset,
176 context->mtd_info.erasesize);
177 low_mem.size = flash_offset - low_mem.flash_offset;
178 high_mem.flash_offset = flash_offset + count_bytes;
179 high_mem.size = align_up(high_mem.flash_offset,
180 context->mtd_info.erasesize) -
181 high_mem.flash_offset;
182
183 /*
184 * Check if we already have a copy of the required flash areas in
185 * memory as part of the existing window
186 */
187 if (low_mem.flash_offset < context->current->flash_offset) {
188 /* Before the start of our current window */
189 low_mem.mem = malloc(low_mem.size);
190 if (!low_mem.mem) {
191 MSG_ERR("Unable to allocate memory\n");
192 return -MBOX_R_SYSTEM_ERROR;
193 }
194 rc = copy_flash(context, low_mem.flash_offset,
195 low_mem.mem, low_mem.size);
196 if (rc < 0) {
197 goto out;
198 }
199 }
200 if ((high_mem.flash_offset + high_mem.size) >
201 (context->current->flash_offset + context->current->size)) {
202 /* After the end of our current window */
203 high_mem.mem = malloc(high_mem.size);
204 if (!high_mem.mem) {
205 MSG_ERR("Unable to allocate memory\n");
206 rc = -MBOX_R_SYSTEM_ERROR;
207 goto out;
208 }
209 rc = copy_flash(context, high_mem.flash_offset,
210 high_mem.mem, high_mem.size);
211 if (rc < 0) {
212 goto out;
213 }
214 }
215
216 /*
217 * We need to erase the flash from low_mem.flash_offset->
218 * high_mem.flash_offset + high_mem.size
219 */
220 rc = erase_flash(context, low_mem.flash_offset,
221 (high_mem.flash_offset - low_mem.flash_offset) +
222 high_mem.size);
223 if (rc < 0) {
224 MSG_ERR("Couldn't erase flash\n");
225 goto out;
226 }
227
228 /* Write back over the erased area */
229 if (low_mem.mem) {
230 /* Exceed window at the start */
231 rc = write_flash(context, low_mem.flash_offset, low_mem.mem,
232 low_mem.size);
233 if (rc < 0) {
234 goto out;
235 }
236 }
237 rc = write_flash(context, flash_offset,
238 context->current->mem + offset_bytes, count_bytes);
239 if (rc < 0) {
240 goto out;
241 }
242 /*
243 * We still need to write the last little bit that we erased - it's
244 * either in the current window or the high_mem window.
245 */
246 if (high_mem.mem) {
247 /* Exceed window at the end */
248 rc = write_flash(context, high_mem.flash_offset, high_mem.mem,
249 high_mem.size);
250 if (rc < 0) {
251 goto out;
252 }
253 } else {
254 /* Write from the current window - it's atleast that big */
255 rc = write_flash(context, high_mem.flash_offset,
256 context->current->mem + offset_bytes +
257 count_bytes, high_mem.size);
258 if (rc < 0) {
259 goto out;
260 }
261 }
262
263out:
264 free(low_mem.mem);
265 free(high_mem.mem);
266 return rc;
267}
268
269/*
270 * write_from_window() - Write back to the flash from the current window
271 * @context: The mbox context pointer
272 * @offset_bytes: The offset in the current window to write from (blocks)
273 * @count_bytes: Number of blocks to write
274 * @type: Whether this is an erase & write or just an erase
275 *
276 * Return: 0 on success otherwise negative error code
277 */
278int write_from_window(struct mbox_context *context, uint32_t offset,
279 uint32_t count, uint8_t type)
280{
281 int rc;
282 uint32_t flash_offset, count_bytes = count << context->block_size_shift;
283 uint32_t offset_bytes = offset << context->block_size_shift;
284
285 switch (type) {
286 case WINDOW_ERASED: /* >= V2 ONLY -> block_size == erasesize */
287 flash_offset = context->current->flash_offset + offset_bytes;
288 rc = erase_flash(context, flash_offset, count_bytes);
289 if (rc < 0) {
290 MSG_ERR("Couldn't erase flash\n");
291 return rc;
292 }
293 break;
294 case WINDOW_DIRTY:
295 /*
296 * For protocol V1, block_size may be smaller than erase size
297 * so we have a special function to make sure that we do this
298 * correctly without losing data.
299 */
300 if (log_2(context->mtd_info.erasesize) !=
301 context->block_size_shift) {
302 return write_from_window_v1(context, offset_bytes,
303 count_bytes);
304 }
305 flash_offset = context->current->flash_offset + offset_bytes;
306
307 /* Erase the flash */
308 rc = erase_flash(context, flash_offset, count_bytes);
309 if (rc < 0) {
310 return rc;
311 }
312
313 /* Write to the erased flash */
314 rc = write_flash(context, flash_offset,
315 context->current->mem + offset_bytes,
316 count_bytes);
317 if (rc < 0) {
318 return rc;
319 }
320
321 break;
322 default:
323 /* We shouldn't be able to get here */
324 MSG_ERR("Write from window with invalid type: %d\n", type);
325 return -MBOX_R_SYSTEM_ERROR;
326 }
327
328 return 0;
329}
330
331/* Window Management Functions */
332
333/*
334 * alloc_window_dirty_bytemap() - (re)allocate all the window dirty bytemaps
335 * @context: The mbox context pointer
336 */
337void alloc_window_dirty_bytemap(struct mbox_context *context)
338{
339 struct window_context *cur;
340 int i;
341
342 for (i = 0; i < context->windows.num; i++) {
343 cur = &context->windows.window[i];
344 /* There may already be one allocated */
345 free(cur->dirty_bmap);
346 /* Allocate the new one */
347 cur->dirty_bmap = calloc((cur->size >>
348 context->block_size_shift),
349 sizeof(*cur->dirty_bmap));
350 }
351}
352
353/*
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100354 * set_window_bytemap() - Set the window bytemap
355 * @context: The mbox context pointer
356 * @cur: The window to set the bytemap of
357 * @offset: Where in the window to set the bytemap (blocks)
358 * @size: The number of blocks to set
359 * @val: The value to set the bytemap to
360 *
361 * Return: 0 on success otherwise negative error code
362 */
363int set_window_bytemap(struct mbox_context *context, struct window_context *cur,
364 uint32_t offset, uint32_t size, uint8_t val)
365{
366 if (offset + size > (cur->size >> context->block_size_shift)) {
367 MSG_ERR("Tried to set window bytemap past end of window\n");
368 MSG_ERR("Requested offset: 0x%x size: 0x%x window size: 0x%x\n",
369 offset << context->block_size_shift,
370 size << context->block_size_shift,
371 cur->size << context->block_size_shift);
372 return -MBOX_R_PARAM_ERROR;
373 }
374
375 memset(cur->dirty_bmap + offset, val, size);
376 return 0;
377}
378
379/*
380 * close_current_window() - Close the current (active) window
381 * @context: The mbox context pointer
382 * @set_bmc_event: Whether to set the bmc event bit
383 * @flags: Flags as defined for a close command in the protocol
384 *
385 * This closes the current window. If the host has requested the current window
386 * be closed then we don't need to set the bmc event bit
387 * (set_bmc_event == false), otherwise if the current window has been closed
388 * without the host requesting it the bmc event bit must be set to indicate this
389 * to the host (set_bmc_event == true).
390 */
391void close_current_window(struct mbox_context *context, bool set_bmc_event,
392 uint8_t flags)
393{
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000394 MSG_DBG("Close current window, flags: 0x%.2x\n", flags);
395
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100396 if (set_bmc_event) {
397 set_bmc_events(context, BMC_EVENT_WINDOW_RESET, SET_BMC_EVENT);
398 }
399
400 if (flags & FLAGS_SHORT_LIFETIME) {
401 context->current->age = 0;
402 }
403
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100404 context->current = NULL;
405 context->current_is_write = false;
406}
407
408/*
409 * reset_window() - Reset a window context to a well defined default state
410 * @context: The mbox context pointer
411 * @window: The window to reset
412 */
413void reset_window(struct mbox_context *context, struct window_context *window)
414{
415 window->flash_offset = FLASH_OFFSET_UNINIT;
416 window->size = context->windows.default_size;
417 if (window->dirty_bmap) { /* Might not have been allocated */
418 set_window_bytemap(context, window, 0,
419 window->size >> context->block_size_shift,
420 WINDOW_CLEAN);
421 }
422 window->age = 0;
423}
424
425/*
426 * reset_all_windows() - Reset all windows to a well defined default state
427 * @context: The mbox context pointer
428 * @set_bmc_event: If any state change should be indicated to the host
429 */
430void reset_all_windows(struct mbox_context *context, bool set_bmc_event)
431{
432 int i;
433
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000434 MSG_DBG("Resetting all windows\n");
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100435 /* We might have an open window which needs closing */
436 if (context->current) {
437 close_current_window(context, set_bmc_event, FLAGS_NONE);
438 }
439 for (i = 0; i < context->windows.num; i++) {
440 reset_window(context, &context->windows.window[i]);
441 }
442
443 context->windows.max_age = 0;
444}
445
446/*
447 * find_oldest_window() - Find the oldest (Least Recently Used) window
448 * @context: The mbox context pointer
449 *
450 * Return: Pointer to the least recently used window
451 */
452struct window_context *find_oldest_window(struct mbox_context *context)
453{
454 struct window_context *oldest = NULL, *cur;
455 uint32_t min_age = context->windows.max_age + 1;
456 int i;
457
458 for (i = 0; i < context->windows.num; i++) {
459 cur = &context->windows.window[i];
460
461 if (cur->age < min_age) {
462 min_age = cur->age;
463 oldest = cur;
464 }
465 }
466
467 return oldest;
468}
469
470/*
Suraj Jitindar Singh5a3a0662017-04-27 11:55:26 +1000471 * find_largest_window() - Find the largest window in the window cache
472 * @context: The mbox context pointer
473 *
474 * Return: The largest window
475 */
476struct window_context *find_largest_window(struct mbox_context *context)
477{
478 struct window_context *largest = NULL, *cur;
479 uint32_t max_size = 0;
480 int i;
481
482 for (i = 0; i < context->windows.num; i++) {
483 cur = &context->windows.window[i];
484
485 if (cur->size > max_size) {
486 max_size = cur->size;
487 largest = cur;
488 }
489 }
490
491 return largest;
492}
493
494/*
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100495 * search_windows() - Search the window cache for a window containing offset
496 * @context: The mbox context pointer
497 * @offset: Absolute flash offset to search for (bytes)
498 * @exact: If the window must exactly map the requested offset
499 *
500 * This will search the cache of windows for one containing the requested
501 * offset. For V1 of the protocol windows must exactly map the offset since we
502 * can't tell the host how much of its request we actually mapped and it will
503 * thus assume it can access window->size from the offset we give it.
504 *
505 * Return: Pointer to a window containing the requested offset otherwise
506 * NULL
507 */
508struct window_context *search_windows(struct mbox_context *context,
509 uint32_t offset, bool exact)
510{
511 struct window_context *cur;
512 int i;
513
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000514 MSG_DBG("Searching for window which contains 0x%.8x %s\n",
515 offset, exact ? "exactly" : "");
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100516 for (i = 0; i < context->windows.num; i++) {
517 cur = &context->windows.window[i];
518 if (cur->flash_offset == FLASH_OFFSET_UNINIT) {
519 /* Uninitialised Window */
520 if (offset == FLASH_OFFSET_UNINIT) {
521 return cur;
522 }
523 continue;
524 }
525 if ((offset >= cur->flash_offset) &&
526 (offset < (cur->flash_offset + cur->size))) {
527 if (exact && (cur->flash_offset != offset)) {
528 continue;
529 }
530 /* This window contains the requested offset */
531 cur->age = ++(context->windows.max_age);
532 return cur;
533 }
534 }
535
536 return NULL;
537}
538
539/*
540 * create_map_window() - Create a window mapping which maps the requested offset
541 * @context: The mbox context pointer
542 * @this_window: A pointer to update to the "new" window
543 * @offset: Absolute flash offset to create a mapping for (bytes)
544 * @exact: If the window must exactly map the requested offset
545 *
546 * This is used to create a window mapping for the requested offset when there
547 * is no existing window in the cache which satisfies the offset. This involves
548 * choosing an existing window from the window cache to evict so we can use it
549 * to store the flash contents from the requested offset, we then point the
550 * caller to that window since it now maps their request.
551 *
552 * Return: 0 on success otherwise negative error code
553 */
554int create_map_window(struct mbox_context *context,
555 struct window_context **this_window, uint32_t offset,
556 bool exact)
557{
558 struct window_context *cur = NULL;
559 int rc;
560
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000561 MSG_DBG("Creating window which maps 0x%.8x %s\n", offset,
562 exact ? "exactly" : "");
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100563
564 /* Search for an uninitialised window, use this before evicting */
565 cur = search_windows(context, FLASH_OFFSET_UNINIT, true);
566
567 /* No uninitialised window found, we need to choose one to "evict" */
568 if (!cur) {
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000569 MSG_DBG("No uninitialised window, evicting one\n");
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100570 cur = find_oldest_window(context);
571 }
572
Deepak Kodihalliaee73892017-07-12 13:18:06 -0500573/*
574 * In case of the virtual pnor, as of now it's possible that a window may
575 * have content less than it's max size. We basically copy one flash partition
576 * per window, and some partitions are smaller than the max size. An offset
577 * right after such a small partition ends should lead to new mapping. The code
578 * below prevents that.
579 */
580#ifndef VIRTUAL_PNOR_ENABLED
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100581 if (!exact) {
582 /*
583 * It would be nice to align the offsets which we map to window
584 * size, this will help prevent overlap which would be an
585 * inefficient use of our reserved memory area (we would like
586 * to "cache" as much of the acutal flash as possible in
587 * memory). If we're protocol V1 however we must ensure the
588 * offset requested is exactly mapped.
589 */
590 offset &= ~(cur->size - 1);
591 }
Deepak Kodihalliaee73892017-07-12 13:18:06 -0500592#endif
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100593
594 if ((offset + cur->size) > context->flash_size) {
595 /*
596 * There is V1 skiboot implementations out there which don't
597 * mask offset with window size, meaning when we have
598 * window size == flash size we will never allow the host to
599 * open a window except at 0x0, which isn't always where the
600 * host requests it. Thus we have to ignore this check and just
601 * hope the host doesn't access past the end of the window
602 * (which it shouldn't) for V1 implementations to get around
603 * this.
604 */
605 if (context->version == API_VERSION_1) {
606 cur->size = align_down(context->flash_size - offset,
607 1 << context->block_size_shift);
608 } else {
609 /* Trying to read past the end of flash */
610 MSG_ERR("Tried to open read window past flash limit\n");
611 return -MBOX_R_PARAM_ERROR;
612 }
613 }
614
615 /* Copy from flash into the window buffer */
616 rc = copy_flash(context, offset, cur->mem, cur->size);
617 if (rc < 0) {
618 /* We don't know how much we've copied -> better reset window */
619 reset_window(context, cur);
620 return rc;
621 }
Andrew Jeffery1a3f8432018-03-02 10:18:02 +1030622 /*
623 * rc isn't guaranteed to be aligned, so align up
624 *
625 * FIXME: This should only be the case for the vpnor ToC now, so handle
626 * it there
627 */
Suraj Jitindar Singh8493c332017-10-06 14:29:45 +1100628 cur->size = align_up(rc, (1ULL << context->block_size_shift));
629 /* Would like a known value, pick 0xFF to it looks like erased flash */
630 memset(cur->mem + rc, 0xFF, cur->size - rc);
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100631
632 /*
633 * Since for V1 windows aren't constrained to start at multiples of
634 * window size it's possible that something already maps this offset.
635 * Reset any windows which map this offset to avoid coherency problems.
636 * We just have to check for anything which maps the start or the end
637 * of the window since all windows are the same size so another window
638 * cannot map just the middle of this window.
639 */
640 if (context->version == API_VERSION_1) {
641 uint32_t i;
642
Suraj Jitindar Singh28519592017-04-27 14:48:58 +1000643 MSG_DBG("Checking for window overlap\n");
644
Suraj Jitindar Singhe39c9162017-03-28 10:47:43 +1100645 for (i = offset; i < (offset + cur->size); i += (cur->size - 1)) {
646 struct window_context *tmp = NULL;
647 do {
648 tmp = search_windows(context, i, false);
649 if (tmp) {
650 reset_window(context, tmp);
651 }
652 } while (tmp);
653 }
654 }
655
656 /* Clear the bytemap of the window just loaded -> we know it's clean */
657 set_window_bytemap(context, cur, 0,
658 cur->size >> context->block_size_shift,
659 WINDOW_CLEAN);
660
661 /* Update so we know what's in the window */
662 cur->flash_offset = offset;
663 cur->age = ++(context->windows.max_age);
664 *this_window = cur;
665
666 return 0;
667}