1 // SPDX-License-Identifier: GPL-2.0-only
3 * RAM Oops/Panic logger
5 * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
6 * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 #include <linux/kernel.h>
12 #include <linux/err.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/pstore.h>
17 #include <linux/ioport.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/compiler.h>
21 #include <linux/pstore_ram.h>
23 #include <linux/of_address.h>
26 #define RAMOOPS_KERNMSG_HDR "===="
27 #define MIN_MEM_SIZE 4096UL
29 static ulong record_size
= MIN_MEM_SIZE
;
30 module_param(record_size
, ulong
, 0400);
31 MODULE_PARM_DESC(record_size
,
32 "size of each dump done on oops/panic");
34 static ulong ramoops_console_size
= MIN_MEM_SIZE
;
35 module_param_named(console_size
, ramoops_console_size
, ulong
, 0400);
36 MODULE_PARM_DESC(console_size
, "size of kernel console log");
38 static ulong ramoops_ftrace_size
= MIN_MEM_SIZE
;
39 module_param_named(ftrace_size
, ramoops_ftrace_size
, ulong
, 0400);
40 MODULE_PARM_DESC(ftrace_size
, "size of ftrace log");
42 static ulong ramoops_pmsg_size
= MIN_MEM_SIZE
;
43 module_param_named(pmsg_size
, ramoops_pmsg_size
, ulong
, 0400);
44 MODULE_PARM_DESC(pmsg_size
, "size of user space message log");
46 static unsigned long long mem_address
;
47 module_param_hw(mem_address
, ullong
, other
, 0400);
48 MODULE_PARM_DESC(mem_address
,
49 "start of reserved RAM used to store oops/panic logs");
51 static ulong mem_size
;
52 module_param(mem_size
, ulong
, 0400);
53 MODULE_PARM_DESC(mem_size
,
54 "size of reserved RAM used to store oops/panic logs");
56 static unsigned int mem_type
;
57 module_param(mem_type
, uint
, 0400);
58 MODULE_PARM_DESC(mem_type
,
59 "set to 1 to try to use unbuffered memory (default 0)");
61 static int ramoops_max_reason
= -1;
62 module_param_named(max_reason
, ramoops_max_reason
, int, 0400);
63 MODULE_PARM_DESC(max_reason
,
64 "maximum reason for kmsg dump (default 2: Oops and Panic) ");
66 static int ramoops_ecc
;
67 module_param_named(ecc
, ramoops_ecc
, int, 0400);
68 MODULE_PARM_DESC(ramoops_ecc
,
69 "if non-zero, the option enables ECC support and specifies "
70 "ECC buffer size in bytes (1 is a special value, means 16 "
73 static int ramoops_dump_oops
= -1;
74 module_param_named(dump_oops
, ramoops_dump_oops
, int, 0400);
75 MODULE_PARM_DESC(dump_oops
,
76 "(deprecated: use max_reason instead) set to 1 to dump oopses & panics, 0 to only dump panics");
78 struct ramoops_context
{
79 struct persistent_ram_zone
**dprzs
; /* Oops dump zones */
80 struct persistent_ram_zone
*cprz
; /* Console zone */
81 struct persistent_ram_zone
**fprzs
; /* Ftrace zones */
82 struct persistent_ram_zone
*mprz
; /* PMSG zone */
83 phys_addr_t phys_addr
;
91 struct persistent_ram_ecc_info ecc_info
;
92 unsigned int max_dump_cnt
;
93 unsigned int dump_write_cnt
;
94 /* _read_cnt need clear on ramoops_pstore_open */
95 unsigned int dump_read_cnt
;
96 unsigned int console_read_cnt
;
97 unsigned int max_ftrace_cnt
;
98 unsigned int ftrace_read_cnt
;
99 unsigned int pmsg_read_cnt
;
100 struct pstore_info pstore
;
103 static struct platform_device
*dummy
;
105 static int ramoops_pstore_open(struct pstore_info
*psi
)
107 struct ramoops_context
*cxt
= psi
->data
;
109 cxt
->dump_read_cnt
= 0;
110 cxt
->console_read_cnt
= 0;
111 cxt
->ftrace_read_cnt
= 0;
112 cxt
->pmsg_read_cnt
= 0;
116 static struct persistent_ram_zone
*
117 ramoops_get_next_prz(struct persistent_ram_zone
*przs
[], int id
,
118 struct pstore_record
*record
)
120 struct persistent_ram_zone
*prz
;
122 /* Give up if we never existed or have hit the end. */
130 /* Update old/shadowed buffer. */
131 if (prz
->type
== PSTORE_TYPE_DMESG
)
132 persistent_ram_save_old(prz
);
134 if (!persistent_ram_old_size(prz
))
137 record
->type
= prz
->type
;
143 static int ramoops_read_kmsg_hdr(char *buffer
, struct timespec64
*time
,
147 int header_length
= 0;
149 if (sscanf(buffer
, RAMOOPS_KERNMSG_HDR
"%lld.%lu-%c\n%n",
150 (time64_t
*)&time
->tv_sec
, &time
->tv_nsec
, &data_type
,
151 &header_length
) == 3) {
152 time
->tv_nsec
*= 1000;
153 if (data_type
== 'C')
157 } else if (sscanf(buffer
, RAMOOPS_KERNMSG_HDR
"%lld.%lu\n%n",
158 (time64_t
*)&time
->tv_sec
, &time
->tv_nsec
,
159 &header_length
) == 2) {
160 time
->tv_nsec
*= 1000;
167 return header_length
;
170 static bool prz_ok(struct persistent_ram_zone
*prz
)
172 return !!prz
&& !!(persistent_ram_old_size(prz
) +
173 persistent_ram_ecc_string(prz
, NULL
, 0));
176 static ssize_t
ramoops_pstore_read(struct pstore_record
*record
)
179 struct ramoops_context
*cxt
= record
->psi
->data
;
180 struct persistent_ram_zone
*prz
= NULL
;
181 int header_length
= 0;
182 bool free_prz
= false;
185 * Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but
186 * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have
187 * valid time stamps, so it is initialized to zero.
189 record
->time
.tv_sec
= 0;
190 record
->time
.tv_nsec
= 0;
191 record
->compressed
= false;
193 /* Find the next valid persistent_ram_zone for DMESG */
194 while (cxt
->dump_read_cnt
< cxt
->max_dump_cnt
&& !prz
) {
195 prz
= ramoops_get_next_prz(cxt
->dprzs
, cxt
->dump_read_cnt
++,
199 header_length
= ramoops_read_kmsg_hdr(persistent_ram_old(prz
),
201 &record
->compressed
);
202 /* Clear and skip this DMESG record if it has no valid header */
203 if (!header_length
) {
204 persistent_ram_free_old(prz
);
205 persistent_ram_zap(prz
);
210 if (!prz_ok(prz
) && !cxt
->console_read_cnt
++)
211 prz
= ramoops_get_next_prz(&cxt
->cprz
, 0 /* single */, record
);
213 if (!prz_ok(prz
) && !cxt
->pmsg_read_cnt
++)
214 prz
= ramoops_get_next_prz(&cxt
->mprz
, 0 /* single */, record
);
216 /* ftrace is last since it may want to dynamically allocate memory. */
218 if (!(cxt
->flags
& RAMOOPS_FLAG_FTRACE_PER_CPU
) &&
219 !cxt
->ftrace_read_cnt
++) {
220 prz
= ramoops_get_next_prz(cxt
->fprzs
, 0 /* single */,
224 * Build a new dummy record which combines all the
225 * per-cpu records including metadata and ecc info.
227 struct persistent_ram_zone
*tmp_prz
, *prz_next
;
229 tmp_prz
= kzalloc(sizeof(struct persistent_ram_zone
),
236 while (cxt
->ftrace_read_cnt
< cxt
->max_ftrace_cnt
) {
237 prz_next
= ramoops_get_next_prz(cxt
->fprzs
,
238 cxt
->ftrace_read_cnt
++, record
);
240 if (!prz_ok(prz_next
))
243 tmp_prz
->ecc_info
= prz_next
->ecc_info
;
244 tmp_prz
->corrected_bytes
+=
245 prz_next
->corrected_bytes
;
246 tmp_prz
->bad_blocks
+= prz_next
->bad_blocks
;
248 size
= pstore_ftrace_combine_log(
250 &tmp_prz
->old_log_size
,
252 prz_next
->old_log_size
);
265 size
= persistent_ram_old_size(prz
) - header_length
;
267 /* ECC correction notice */
268 record
->ecc_notice_size
= persistent_ram_ecc_string(prz
, NULL
, 0);
270 record
->buf
= kmalloc(size
+ record
->ecc_notice_size
+ 1, GFP_KERNEL
);
271 if (record
->buf
== NULL
) {
276 memcpy(record
->buf
, (char *)persistent_ram_old(prz
) + header_length
,
279 persistent_ram_ecc_string(prz
, record
->buf
+ size
,
280 record
->ecc_notice_size
+ 1);
291 static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone
*prz
,
292 struct pstore_record
*record
)
294 char hdr
[36]; /* "===="(4), %lld(20), "."(1), %06lu(6), "-%c\n"(3) */
297 len
= scnprintf(hdr
, sizeof(hdr
),
298 RAMOOPS_KERNMSG_HDR
"%lld.%06lu-%c\n",
299 (time64_t
)record
->time
.tv_sec
,
300 record
->time
.tv_nsec
/ 1000,
301 record
->compressed
? 'C' : 'D');
302 persistent_ram_write(prz
, hdr
, len
);
307 static int notrace
ramoops_pstore_write(struct pstore_record
*record
)
309 struct ramoops_context
*cxt
= record
->psi
->data
;
310 struct persistent_ram_zone
*prz
;
313 if (record
->type
== PSTORE_TYPE_CONSOLE
) {
316 persistent_ram_write(cxt
->cprz
, record
->buf
, record
->size
);
318 } else if (record
->type
== PSTORE_TYPE_FTRACE
) {
324 * Choose zone by if we're using per-cpu buffers.
326 if (cxt
->flags
& RAMOOPS_FLAG_FTRACE_PER_CPU
)
327 zonenum
= smp_processor_id();
331 persistent_ram_write(cxt
->fprzs
[zonenum
], record
->buf
,
334 } else if (record
->type
== PSTORE_TYPE_PMSG
) {
335 pr_warn_ratelimited("PMSG shouldn't call %s\n", __func__
);
339 if (record
->type
!= PSTORE_TYPE_DMESG
)
343 * We could filter on record->reason here if we wanted to (which
344 * would duplicate what happened before the "max_reason" setting
345 * was added), but that would defeat the purpose of a system
346 * changing printk.always_kmsg_dump, so instead log everything that
347 * the kmsg dumper sends us, since it should be doing the filtering
348 * based on the combination of printk.always_kmsg_dump and our
349 * requested "max_reason".
353 * Explicitly only take the first part of any new crash.
354 * If our buffer is larger than kmsg_bytes, this can never happen,
355 * and if our buffer is smaller than kmsg_bytes, we don't want the
356 * report split across multiple records.
358 if (record
->part
!= 1)
364 prz
= cxt
->dprzs
[cxt
->dump_write_cnt
];
367 * Since this is a new crash dump, we need to reset the buffer in
368 * case it still has an old dump present. Without this, the new dump
369 * will get appended, which would seriously confuse anything trying
370 * to check dump file contents. Specifically, ramoops_read_kmsg_hdr()
371 * expects to find a dump header in the beginning of buffer data, so
372 * we must to reset the buffer values, in order to ensure that the
373 * header will be written to the beginning of the buffer.
375 persistent_ram_zap(prz
);
377 /* Build header and append record contents. */
378 hlen
= ramoops_write_kmsg_hdr(prz
, record
);
383 if (size
+ hlen
> prz
->buffer_size
)
384 size
= prz
->buffer_size
- hlen
;
385 persistent_ram_write(prz
, record
->buf
, size
);
387 cxt
->dump_write_cnt
= (cxt
->dump_write_cnt
+ 1) % cxt
->max_dump_cnt
;
392 static int notrace
ramoops_pstore_write_user(struct pstore_record
*record
,
393 const char __user
*buf
)
395 if (record
->type
== PSTORE_TYPE_PMSG
) {
396 struct ramoops_context
*cxt
= record
->psi
->data
;
400 return persistent_ram_write_user(cxt
->mprz
, buf
, record
->size
);
406 static int ramoops_pstore_erase(struct pstore_record
*record
)
408 struct ramoops_context
*cxt
= record
->psi
->data
;
409 struct persistent_ram_zone
*prz
;
411 switch (record
->type
) {
412 case PSTORE_TYPE_DMESG
:
413 if (record
->id
>= cxt
->max_dump_cnt
)
415 prz
= cxt
->dprzs
[record
->id
];
417 case PSTORE_TYPE_CONSOLE
:
420 case PSTORE_TYPE_FTRACE
:
421 if (record
->id
>= cxt
->max_ftrace_cnt
)
423 prz
= cxt
->fprzs
[record
->id
];
425 case PSTORE_TYPE_PMSG
:
432 persistent_ram_free_old(prz
);
433 persistent_ram_zap(prz
);
438 static struct ramoops_context oops_cxt
= {
440 .owner
= THIS_MODULE
,
442 .open
= ramoops_pstore_open
,
443 .read
= ramoops_pstore_read
,
444 .write
= ramoops_pstore_write
,
445 .write_user
= ramoops_pstore_write_user
,
446 .erase
= ramoops_pstore_erase
,
450 static void ramoops_free_przs(struct ramoops_context
*cxt
)
456 for (i
= 0; i
< cxt
->max_dump_cnt
; i
++)
457 persistent_ram_free(cxt
->dprzs
[i
]);
460 cxt
->max_dump_cnt
= 0;
463 /* Free ftrace PRZs */
465 for (i
= 0; i
< cxt
->max_ftrace_cnt
; i
++)
466 persistent_ram_free(cxt
->fprzs
[i
]);
468 cxt
->max_ftrace_cnt
= 0;
472 static int ramoops_init_przs(const char *name
,
473 struct device
*dev
, struct ramoops_context
*cxt
,
474 struct persistent_ram_zone
***przs
,
475 phys_addr_t
*paddr
, size_t mem_sz
,
477 unsigned int *cnt
, u32 sig
, u32 flags
)
482 struct persistent_ram_zone
**prz_ar
;
484 /* Allocate nothing for 0 mem_sz or 0 record_size. */
485 if (mem_sz
== 0 || record_size
== 0) {
491 * If we have a negative record size, calculate it based on
492 * mem_sz / *cnt. If we have a positive record size, calculate
493 * cnt from mem_sz / record_size.
495 if (record_size
< 0) {
498 record_size
= mem_sz
/ *cnt
;
499 if (record_size
== 0) {
500 dev_err(dev
, "%s record size == 0 (%zu / %u)\n",
505 *cnt
= mem_sz
/ record_size
;
507 dev_err(dev
, "%s record count == 0 (%zu / %zu)\n",
508 name
, mem_sz
, record_size
);
513 if (*paddr
+ mem_sz
- cxt
->phys_addr
> cxt
->size
) {
514 dev_err(dev
, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
516 mem_sz
, (unsigned long long)*paddr
,
517 cxt
->size
, (unsigned long long)cxt
->phys_addr
);
521 zone_sz
= mem_sz
/ *cnt
;
523 dev_err(dev
, "%s zone size == 0\n", name
);
527 prz_ar
= kcalloc(*cnt
, sizeof(**przs
), GFP_KERNEL
);
531 for (i
= 0; i
< *cnt
; i
++) {
535 label
= kasprintf(GFP_KERNEL
, "ramoops:%s", name
);
537 label
= kasprintf(GFP_KERNEL
, "ramoops:%s(%d/%d)",
539 prz_ar
[i
] = persistent_ram_new(*paddr
, zone_sz
, sig
,
541 cxt
->memtype
, flags
, label
);
543 if (IS_ERR(prz_ar
[i
])) {
544 err
= PTR_ERR(prz_ar
[i
]);
545 dev_err(dev
, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
547 (unsigned long long)*paddr
, err
);
551 persistent_ram_free(prz_ar
[i
]);
557 prz_ar
[i
]->type
= pstore_name_to_type(name
);
568 static int ramoops_init_prz(const char *name
,
569 struct device
*dev
, struct ramoops_context
*cxt
,
570 struct persistent_ram_zone
**prz
,
571 phys_addr_t
*paddr
, size_t sz
, u32 sig
)
578 if (*paddr
+ sz
- cxt
->phys_addr
> cxt
->size
) {
579 dev_err(dev
, "no room for %s mem region (0x%zx@0x%llx) in (0x%lx@0x%llx)\n",
580 name
, sz
, (unsigned long long)*paddr
,
581 cxt
->size
, (unsigned long long)cxt
->phys_addr
);
585 label
= kasprintf(GFP_KERNEL
, "ramoops:%s", name
);
586 *prz
= persistent_ram_new(*paddr
, sz
, sig
, &cxt
->ecc_info
,
587 cxt
->memtype
, PRZ_FLAG_ZAP_OLD
, label
);
590 int err
= PTR_ERR(*prz
);
592 dev_err(dev
, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
593 name
, sz
, (unsigned long long)*paddr
, err
);
598 (*prz
)->type
= pstore_name_to_type(name
);
603 /* Read a u32 from a dt property and make sure it's safe for an int. */
604 static int ramoops_parse_dt_u32(struct platform_device
*pdev
,
605 const char *propname
,
606 u32 default_value
, u32
*value
)
611 ret
= of_property_read_u32(pdev
->dev
.of_node
, propname
, &val32
);
612 if (ret
== -EINVAL
) {
613 /* field is missing, use default value. */
614 val32
= default_value
;
615 } else if (ret
< 0) {
616 dev_err(&pdev
->dev
, "failed to parse property %s: %d\n",
621 /* Sanity check our results. */
622 if (val32
> INT_MAX
) {
623 dev_err(&pdev
->dev
, "%s %u > INT_MAX\n", propname
, val32
);
631 static int ramoops_parse_dt(struct platform_device
*pdev
,
632 struct ramoops_platform_data
*pdata
)
634 struct device_node
*of_node
= pdev
->dev
.of_node
;
635 struct device_node
*parent_node
;
636 struct resource
*res
;
640 dev_dbg(&pdev
->dev
, "using Device Tree\n");
642 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
645 "failed to locate DT /reserved-memory resource\n");
649 pdata
->mem_size
= resource_size(res
);
650 pdata
->mem_address
= res
->start
;
651 pdata
->mem_type
= of_property_read_bool(of_node
, "unbuffered");
653 * Setting "no-dump-oops" is deprecated and will be ignored if
654 * "max_reason" is also specified.
656 if (of_property_read_bool(of_node
, "no-dump-oops"))
657 pdata
->max_reason
= KMSG_DUMP_PANIC
;
659 pdata
->max_reason
= KMSG_DUMP_OOPS
;
661 #define parse_u32(name, field, default_value) { \
662 ret = ramoops_parse_dt_u32(pdev, name, default_value, \
669 parse_u32("record-size", pdata
->record_size
, 0);
670 parse_u32("console-size", pdata
->console_size
, 0);
671 parse_u32("ftrace-size", pdata
->ftrace_size
, 0);
672 parse_u32("pmsg-size", pdata
->pmsg_size
, 0);
673 parse_u32("ecc-size", pdata
->ecc_info
.ecc_size
, 0);
674 parse_u32("flags", pdata
->flags
, 0);
675 parse_u32("max-reason", pdata
->max_reason
, pdata
->max_reason
);
680 * Some old Chromebooks relied on the kernel setting the
681 * console_size and pmsg_size to the record size since that's
682 * what the downstream kernel did. These same Chromebooks had
683 * "ramoops" straight under the root node which isn't
684 * according to the current upstream bindings (though it was
685 * arguably acceptable under a prior version of the bindings).
686 * Let's make those old Chromebooks work by detecting that
687 * we're not a child of "reserved-memory" and mimicking the
690 parent_node
= of_get_parent(of_node
);
691 if (!of_node_name_eq(parent_node
, "reserved-memory") &&
692 !pdata
->console_size
&& !pdata
->ftrace_size
&&
693 !pdata
->pmsg_size
&& !pdata
->ecc_info
.ecc_size
) {
694 pdata
->console_size
= pdata
->record_size
;
695 pdata
->pmsg_size
= pdata
->record_size
;
697 of_node_put(parent_node
);
702 static int ramoops_probe(struct platform_device
*pdev
)
704 struct device
*dev
= &pdev
->dev
;
705 struct ramoops_platform_data
*pdata
= dev
->platform_data
;
706 struct ramoops_platform_data pdata_local
;
707 struct ramoops_context
*cxt
= &oops_cxt
;
713 * Only a single ramoops area allowed at a time, so fail extra
716 if (cxt
->max_dump_cnt
) {
717 pr_err("already initialized\n");
721 if (dev_of_node(dev
) && !pdata
) {
722 pdata
= &pdata_local
;
723 memset(pdata
, 0, sizeof(*pdata
));
725 err
= ramoops_parse_dt(pdev
, pdata
);
730 /* Make sure we didn't get bogus platform data pointer. */
732 pr_err("NULL platform data\n");
736 if (!pdata
->mem_size
|| (!pdata
->record_size
&& !pdata
->console_size
&&
737 !pdata
->ftrace_size
&& !pdata
->pmsg_size
)) {
738 pr_err("The memory size and the record/console size must be "
743 if (pdata
->record_size
&& !is_power_of_2(pdata
->record_size
))
744 pdata
->record_size
= rounddown_pow_of_two(pdata
->record_size
);
745 if (pdata
->console_size
&& !is_power_of_2(pdata
->console_size
))
746 pdata
->console_size
= rounddown_pow_of_two(pdata
->console_size
);
747 if (pdata
->ftrace_size
&& !is_power_of_2(pdata
->ftrace_size
))
748 pdata
->ftrace_size
= rounddown_pow_of_two(pdata
->ftrace_size
);
749 if (pdata
->pmsg_size
&& !is_power_of_2(pdata
->pmsg_size
))
750 pdata
->pmsg_size
= rounddown_pow_of_two(pdata
->pmsg_size
);
752 cxt
->size
= pdata
->mem_size
;
753 cxt
->phys_addr
= pdata
->mem_address
;
754 cxt
->memtype
= pdata
->mem_type
;
755 cxt
->record_size
= pdata
->record_size
;
756 cxt
->console_size
= pdata
->console_size
;
757 cxt
->ftrace_size
= pdata
->ftrace_size
;
758 cxt
->pmsg_size
= pdata
->pmsg_size
;
759 cxt
->flags
= pdata
->flags
;
760 cxt
->ecc_info
= pdata
->ecc_info
;
762 paddr
= cxt
->phys_addr
;
764 dump_mem_sz
= cxt
->size
- cxt
->console_size
- cxt
->ftrace_size
766 err
= ramoops_init_przs("dmesg", dev
, cxt
, &cxt
->dprzs
, &paddr
,
767 dump_mem_sz
, cxt
->record_size
,
768 &cxt
->max_dump_cnt
, 0, 0);
772 err
= ramoops_init_prz("console", dev
, cxt
, &cxt
->cprz
, &paddr
,
773 cxt
->console_size
, 0);
777 cxt
->max_ftrace_cnt
= (cxt
->flags
& RAMOOPS_FLAG_FTRACE_PER_CPU
)
780 err
= ramoops_init_przs("ftrace", dev
, cxt
, &cxt
->fprzs
, &paddr
,
781 cxt
->ftrace_size
, -1,
782 &cxt
->max_ftrace_cnt
, LINUX_VERSION_CODE
,
783 (cxt
->flags
& RAMOOPS_FLAG_FTRACE_PER_CPU
)
784 ? PRZ_FLAG_NO_LOCK
: 0);
788 err
= ramoops_init_prz("pmsg", dev
, cxt
, &cxt
->mprz
, &paddr
,
793 cxt
->pstore
.data
= cxt
;
795 * Prepare frontend flags based on which areas are initialized.
796 * For ramoops_init_przs() cases, the "max count" variable tells
797 * if there are regions present. For ramoops_init_prz() cases,
798 * the single region size is how to check.
800 cxt
->pstore
.flags
= 0;
801 if (cxt
->max_dump_cnt
) {
802 cxt
->pstore
.flags
|= PSTORE_FLAGS_DMESG
;
803 cxt
->pstore
.max_reason
= pdata
->max_reason
;
805 if (cxt
->console_size
)
806 cxt
->pstore
.flags
|= PSTORE_FLAGS_CONSOLE
;
807 if (cxt
->max_ftrace_cnt
)
808 cxt
->pstore
.flags
|= PSTORE_FLAGS_FTRACE
;
810 cxt
->pstore
.flags
|= PSTORE_FLAGS_PMSG
;
813 * Since bufsize is only used for dmesg crash dumps, it
814 * must match the size of the dprz record (after PRZ header
815 * and ECC bytes have been accounted for).
817 if (cxt
->pstore
.flags
& PSTORE_FLAGS_DMESG
) {
818 cxt
->pstore
.bufsize
= cxt
->dprzs
[0]->buffer_size
;
819 cxt
->pstore
.buf
= kzalloc(cxt
->pstore
.bufsize
, GFP_KERNEL
);
820 if (!cxt
->pstore
.buf
) {
821 pr_err("cannot allocate pstore crash dump buffer\n");
827 err
= pstore_register(&cxt
->pstore
);
829 pr_err("registering with pstore failed\n");
834 * Update the module parameter variables as well so they are visible
835 * through /sys/module/ramoops/parameters/
837 mem_size
= pdata
->mem_size
;
838 mem_address
= pdata
->mem_address
;
839 record_size
= pdata
->record_size
;
840 ramoops_max_reason
= pdata
->max_reason
;
841 ramoops_console_size
= pdata
->console_size
;
842 ramoops_pmsg_size
= pdata
->pmsg_size
;
843 ramoops_ftrace_size
= pdata
->ftrace_size
;
845 pr_info("using 0x%lx@0x%llx, ecc: %d\n",
846 cxt
->size
, (unsigned long long)cxt
->phys_addr
,
847 cxt
->ecc_info
.ecc_size
);
852 kfree(cxt
->pstore
.buf
);
854 cxt
->pstore
.bufsize
= 0;
855 persistent_ram_free(cxt
->mprz
);
858 persistent_ram_free(cxt
->cprz
);
860 ramoops_free_przs(cxt
);
865 static int ramoops_remove(struct platform_device
*pdev
)
867 struct ramoops_context
*cxt
= &oops_cxt
;
869 pstore_unregister(&cxt
->pstore
);
871 kfree(cxt
->pstore
.buf
);
872 cxt
->pstore
.bufsize
= 0;
874 persistent_ram_free(cxt
->mprz
);
875 persistent_ram_free(cxt
->cprz
);
876 ramoops_free_przs(cxt
);
881 static const struct of_device_id dt_match
[] = {
882 { .compatible
= "ramoops" },
886 static struct platform_driver ramoops_driver
= {
887 .probe
= ramoops_probe
,
888 .remove
= ramoops_remove
,
891 .of_match_table
= dt_match
,
895 static inline void ramoops_unregister_dummy(void)
897 platform_device_unregister(dummy
);
901 static void __init
ramoops_register_dummy(void)
903 struct ramoops_platform_data pdata
;
906 * Prepare a dummy platform data structure to carry the module
907 * parameters. If mem_size isn't set, then there are no module
908 * parameters, and we can skip this.
913 pr_info("using module parameters\n");
915 memset(&pdata
, 0, sizeof(pdata
));
916 pdata
.mem_size
= mem_size
;
917 pdata
.mem_address
= mem_address
;
918 pdata
.mem_type
= mem_type
;
919 pdata
.record_size
= record_size
;
920 pdata
.console_size
= ramoops_console_size
;
921 pdata
.ftrace_size
= ramoops_ftrace_size
;
922 pdata
.pmsg_size
= ramoops_pmsg_size
;
923 /* If "max_reason" is set, its value has priority over "dump_oops". */
924 if (ramoops_max_reason
>= 0)
925 pdata
.max_reason
= ramoops_max_reason
;
926 /* Otherwise, if "dump_oops" is set, parse it into "max_reason". */
927 else if (ramoops_dump_oops
!= -1)
928 pdata
.max_reason
= ramoops_dump_oops
? KMSG_DUMP_OOPS
930 /* And if neither are explicitly set, use the default. */
932 pdata
.max_reason
= KMSG_DUMP_OOPS
;
933 pdata
.flags
= RAMOOPS_FLAG_FTRACE_PER_CPU
;
936 * For backwards compatibility ramoops.ecc=1 means 16 bytes ECC
937 * (using 1 byte for ECC isn't much of use anyway).
939 pdata
.ecc_info
.ecc_size
= ramoops_ecc
== 1 ? 16 : ramoops_ecc
;
941 dummy
= platform_device_register_data(NULL
, "ramoops", -1,
942 &pdata
, sizeof(pdata
));
944 pr_info("could not create platform device: %ld\n",
950 static int __init
ramoops_init(void)
954 ramoops_register_dummy();
955 ret
= platform_driver_register(&ramoops_driver
);
957 ramoops_unregister_dummy();
961 postcore_initcall(ramoops_init
);
963 static void __exit
ramoops_exit(void)
965 platform_driver_unregister(&ramoops_driver
);
966 ramoops_unregister_dummy();
968 module_exit(ramoops_exit
);
970 MODULE_LICENSE("GPL");
971 MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
972 MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");