WSL2-Linux-Kernel/drivers/mtd/mtdoops.c

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C
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// SPDX-License-Identifier: GPL-2.0-only
/*
* MTD Oops/Panic logger
*
* Copyright © 2007 Nokia Corporation. All rights reserved.
*
* Author: Richard Purdie <rpurdie@openedhand.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/console.h>
#include <linux/vmalloc.h>
#include <linux/workqueue.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/timekeeping.h>
#include <linux/mtd/mtd.h>
#include <linux/kmsg_dump.h>
/* Maximum MTD partition size */
#define MTDOOPS_MAX_MTD_SIZE (8 * 1024 * 1024)
static unsigned long record_size = 4096;
module_param(record_size, ulong, 0400);
MODULE_PARM_DESC(record_size,
"record size for MTD OOPS pages in bytes (default 4096)");
static char mtddev[80];
module_param_string(mtddev, mtddev, 80, 0400);
MODULE_PARM_DESC(mtddev,
"name or index number of the MTD device to use");
static int dump_oops = 1;
module_param(dump_oops, int, 0600);
MODULE_PARM_DESC(dump_oops,
"set to 1 to dump oopses, 0 to only dump panics (default 1)");
#define MTDOOPS_KERNMSG_MAGIC_v1 0x5d005d00 /* Original */
#define MTDOOPS_KERNMSG_MAGIC_v2 0x5d005e00 /* Adds the timestamp */
struct mtdoops_hdr {
u32 seq;
u32 magic;
ktime_t timestamp;
} __packed;
static struct mtdoops_context {
struct kmsg_dumper dump;
int mtd_index;
struct work_struct work_erase;
struct work_struct work_write;
struct mtd_info *mtd;
int oops_pages;
int nextpage;
int nextcount;
unsigned long *oops_page_used;
unsigned long oops_buf_busy;
void *oops_buf;
} oops_cxt;
static void mark_page_used(struct mtdoops_context *cxt, int page)
{
set_bit(page, cxt->oops_page_used);
}
static void mark_page_unused(struct mtdoops_context *cxt, int page)
{
clear_bit(page, cxt->oops_page_used);
}
static int page_is_used(struct mtdoops_context *cxt, int page)
{
return test_bit(page, cxt->oops_page_used);
}
static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset)
{
struct mtd_info *mtd = cxt->mtd;
u32 start_page_offset = mtd_div_by_eb(offset, mtd) * mtd->erasesize;
u32 start_page = start_page_offset / record_size;
u32 erase_pages = mtd->erasesize / record_size;
struct erase_info erase;
int ret;
int page;
erase.addr = offset;
erase.len = mtd->erasesize;
ret = mtd_erase(mtd, &erase);
if (ret) {
printk(KERN_WARNING "mtdoops: erase of region [0x%llx, 0x%llx] on \"%s\" failed\n",
(unsigned long long)erase.addr,
(unsigned long long)erase.len, mtddev);
return ret;
}
/* Mark pages as unused */
for (page = start_page; page < start_page + erase_pages; page++)
mark_page_unused(cxt, page);
return 0;
}
static void mtdoops_inc_counter(struct mtdoops_context *cxt)
{
cxt->nextpage++;
if (cxt->nextpage >= cxt->oops_pages)
cxt->nextpage = 0;
cxt->nextcount++;
if (cxt->nextcount == 0xffffffff)
cxt->nextcount = 0;
if (page_is_used(cxt, cxt->nextpage)) {
schedule_work(&cxt->work_erase);
return;
}
printk(KERN_DEBUG "mtdoops: ready %d, %d (no erase)\n",
cxt->nextpage, cxt->nextcount);
}
/* Scheduled work - when we can't proceed without erasing a block */
static void mtdoops_workfunc_erase(struct work_struct *work)
{
struct mtdoops_context *cxt =
container_of(work, struct mtdoops_context, work_erase);
struct mtd_info *mtd = cxt->mtd;
int i = 0, j, ret, mod;
/* We were unregistered */
if (!mtd)
return;
mod = (cxt->nextpage * record_size) % mtd->erasesize;
if (mod != 0) {
cxt->nextpage = cxt->nextpage + ((mtd->erasesize - mod) / record_size);
if (cxt->nextpage >= cxt->oops_pages)
cxt->nextpage = 0;
}
while ((ret = mtd_block_isbad(mtd, cxt->nextpage * record_size)) > 0) {
badblock:
printk(KERN_WARNING "mtdoops: bad block at %08lx\n",
cxt->nextpage * record_size);
i++;
cxt->nextpage = cxt->nextpage + (mtd->erasesize / record_size);
if (cxt->nextpage >= cxt->oops_pages)
cxt->nextpage = 0;
if (i == cxt->oops_pages / (mtd->erasesize / record_size)) {
printk(KERN_ERR "mtdoops: all blocks bad!\n");
return;
}
}
if (ret < 0) {
printk(KERN_ERR "mtdoops: mtd_block_isbad failed, aborting\n");
return;
}
for (j = 0, ret = -1; (j < 3) && (ret < 0); j++)
ret = mtdoops_erase_block(cxt, cxt->nextpage * record_size);
if (ret >= 0) {
printk(KERN_DEBUG "mtdoops: ready %d, %d\n",
cxt->nextpage, cxt->nextcount);
return;
}
if (ret == -EIO) {
ret = mtd_block_markbad(mtd, cxt->nextpage * record_size);
if (ret < 0 && ret != -EOPNOTSUPP) {
printk(KERN_ERR "mtdoops: block_markbad failed, aborting\n");
return;
}
}
goto badblock;
}
static void mtdoops_write(struct mtdoops_context *cxt, int panic)
{
struct mtd_info *mtd = cxt->mtd;
size_t retlen;
struct mtdoops_hdr *hdr;
int ret;
if (test_and_set_bit(0, &cxt->oops_buf_busy))
return;
/* Add mtdoops header to the buffer */
hdr = (struct mtdoops_hdr *)cxt->oops_buf;
hdr->seq = cxt->nextcount;
hdr->magic = MTDOOPS_KERNMSG_MAGIC_v2;
hdr->timestamp = ktime_get_real();
if (panic) {
ret = mtd_panic_write(mtd, cxt->nextpage * record_size,
record_size, &retlen, cxt->oops_buf);
if (ret == -EOPNOTSUPP) {
printk(KERN_ERR "mtdoops: Cannot write from panic without panic_write\n");
goto out;
}
} else
ret = mtd_write(mtd, cxt->nextpage * record_size,
record_size, &retlen, cxt->oops_buf);
if (retlen != record_size || ret < 0)
printk(KERN_ERR "mtdoops: write failure at %ld (%td of %ld written), error %d\n",
cxt->nextpage * record_size, retlen, record_size, ret);
mark_page_used(cxt, cxt->nextpage);
memset(cxt->oops_buf, 0xff, record_size);
mtdoops_inc_counter(cxt);
out:
clear_bit(0, &cxt->oops_buf_busy);
}
static void mtdoops_workfunc_write(struct work_struct *work)
{
struct mtdoops_context *cxt =
container_of(work, struct mtdoops_context, work_write);
mtdoops_write(cxt, 0);
}
static void find_next_position(struct mtdoops_context *cxt)
{
struct mtd_info *mtd = cxt->mtd;
struct mtdoops_hdr hdr;
int ret, page, maxpos = 0;
u32 maxcount = 0xffffffff;
size_t retlen;
for (page = 0; page < cxt->oops_pages; page++) {
if (mtd_block_isbad(mtd, page * record_size))
continue;
/* Assume the page is used */
mark_page_used(cxt, page);
ret = mtd_read(mtd, page * record_size, sizeof(hdr),
&retlen, (u_char *)&hdr);
if (retlen != sizeof(hdr) ||
(ret < 0 && !mtd_is_bitflip(ret))) {
printk(KERN_ERR "mtdoops: read failure at %ld (%zu of %zu read), err %d\n",
page * record_size, retlen, sizeof(hdr), ret);
continue;
}
if (hdr.seq == 0xffffffff && hdr.magic == 0xffffffff)
mark_page_unused(cxt, page);
if (hdr.seq == 0xffffffff ||
(hdr.magic != MTDOOPS_KERNMSG_MAGIC_v1 &&
hdr.magic != MTDOOPS_KERNMSG_MAGIC_v2))
continue;
if (maxcount == 0xffffffff) {
maxcount = hdr.seq;
maxpos = page;
} else if (hdr.seq < 0x40000000 && maxcount > 0xc0000000) {
maxcount = hdr.seq;
maxpos = page;
} else if (hdr.seq > maxcount && hdr.seq < 0xc0000000) {
maxcount = hdr.seq;
maxpos = page;
} else if (hdr.seq > maxcount && hdr.seq > 0xc0000000
&& maxcount > 0x80000000) {
maxcount = hdr.seq;
maxpos = page;
}
}
if (maxcount == 0xffffffff) {
cxt->nextpage = cxt->oops_pages - 1;
cxt->nextcount = 0;
}
else {
cxt->nextpage = maxpos;
cxt->nextcount = maxcount;
}
mtdoops_inc_counter(cxt);
}
static void mtdoops_do_dump(struct kmsg_dumper *dumper,
enum kmsg_dump_reason reason)
{
struct mtdoops_context *cxt = container_of(dumper,
struct mtdoops_context, dump);
struct kmsg_dump_iter iter;
kmsg_dump: constrain mtdoops and ramoops to perform their actions only for KMSG_DUMP_PANIC This series aims to develop logging facility for enterprise use. It is important to save kernel messages reliably on enterprise system because they are helpful for diagnosing system. This series add kmsg_dump() to the paths loosing kernel messages. The use case is the following. [Use case of reboot/poweroff/halt/emergency_restart] My company has often experienced the followings in our support service. - Customer's system suddenly reboots. - Customers ask us to investigate the reason of the reboot. We recognize the fact itself because boot messages remain in /var/log/messages. However, we can't investigate the reason why the system rebooted, because the last messages don't remain. And off course we can't explain the reason. We can solve above problem with this patch as follows. Case1: reboot with command - We can see "Restarting system with command:" or ""Restarting system.". Case2: halt with command - We can see "System halted.". Case3: poweroff with command - We can see " Power down.". Case4: emergency_restart with sysrq. - We can see "Sysrq:" outputted in __handle_sysrq(). Case5: emergency_restart with softdog. - We can see "Initiating system reboot" in watchdog_fire(). So, we can distinguish the reason of reboot, poweroff, halt and emergency_restart. If customer executed reboot command, you may think the customer should know the fact. However, they often claim they don't execute the command when they rebooted system by mistake. No message remains on the current Linux kernel, so we can't show the proof to the customer. This patch improves this situation. This patch: Alters mtdoops and ramoops to perform their actions only for KMSG_DUMP_PANIC, KMSG_DUMP_OOPS and KMSG_DUMP_KEXEC because they would like to log crashes only. Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Marco Stornelli <marco.stornelli@gmail.com> Reviewed-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 03:59:29 +03:00
/* Only dump oopses if dump_oops is set */
if (reason == KMSG_DUMP_OOPS && !dump_oops)
return;
kmsg_dump_rewind(&iter);
if (test_and_set_bit(0, &cxt->oops_buf_busy))
return;
kmsg_dump_get_buffer(&iter, true,
cxt->oops_buf + sizeof(struct mtdoops_hdr),
record_size - sizeof(struct mtdoops_hdr), NULL);
clear_bit(0, &cxt->oops_buf_busy);
if (reason != KMSG_DUMP_OOPS) {
/* Panics must be written immediately */
mtdoops_write(cxt, 1);
} else {
/* For other cases, schedule work to write it "nicely" */
schedule_work(&cxt->work_write);
}
}
static void mtdoops_notify_add(struct mtd_info *mtd)
{
struct mtdoops_context *cxt = &oops_cxt;
u64 mtdoops_pages = div_u64(mtd->size, record_size);
int err;
if (!strcmp(mtd->name, mtddev))
cxt->mtd_index = mtd->index;
if (mtd->index != cxt->mtd_index || cxt->mtd_index < 0)
return;
if (mtd->size < mtd->erasesize * 2) {
printk(KERN_ERR "mtdoops: MTD partition %d not big enough for mtdoops\n",
mtd->index);
return;
}
if (mtd->erasesize < record_size) {
printk(KERN_ERR "mtdoops: eraseblock size of MTD partition %d too small\n",
mtd->index);
return;
}
if (mtd->size > MTDOOPS_MAX_MTD_SIZE) {
printk(KERN_ERR "mtdoops: mtd%d is too large (limit is %d MiB)\n",
mtd->index, MTDOOPS_MAX_MTD_SIZE / 1024 / 1024);
return;
}
/* oops_page_used is a bit field */
treewide: Use array_size() in vmalloc() The vmalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vmalloc(a * b) with: vmalloc(array_size(a, b)) as well as handling cases of: vmalloc(a * b * c) with: vmalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vmalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(char) * COUNT + COUNT , ...) | vmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vmalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vmalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vmalloc(C1 * C2 * C3, ...) | vmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vmalloc(C1 * C2, ...) | vmalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13 00:27:11 +03:00
cxt->oops_page_used =
vmalloc(array_size(sizeof(unsigned long),
DIV_ROUND_UP(mtdoops_pages,
BITS_PER_LONG)));
if (!cxt->oops_page_used) {
printk(KERN_ERR "mtdoops: could not allocate page array\n");
return;
}
cxt->dump.max_reason = KMSG_DUMP_OOPS;
cxt->dump.dump = mtdoops_do_dump;
err = kmsg_dump_register(&cxt->dump);
if (err) {
printk(KERN_ERR "mtdoops: registering kmsg dumper failed, error %d\n", err);
vfree(cxt->oops_page_used);
cxt->oops_page_used = NULL;
return;
}
cxt->mtd = mtd;
cxt->oops_pages = (int)mtd->size / record_size;
find_next_position(cxt);
printk(KERN_INFO "mtdoops: Attached to MTD device %d\n", mtd->index);
}
static void mtdoops_notify_remove(struct mtd_info *mtd)
{
struct mtdoops_context *cxt = &oops_cxt;
if (mtd->index != cxt->mtd_index || cxt->mtd_index < 0)
return;
if (kmsg_dump_unregister(&cxt->dump) < 0)
printk(KERN_WARNING "mtdoops: could not unregister kmsg_dumper\n");
cxt->mtd = NULL;
workqueue: deprecate flush[_delayed]_work_sync() flush[_delayed]_work_sync() are now spurious. Mark them deprecated and convert all users to flush[_delayed]_work(). If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant and the regular flushes guarantee that the work item is not pending or running on any CPU on return, so there's no reason to use the sync flushes at all and they're going away. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mattia Dongili <malattia@linux.it> Cc: Kent Yoder <key@linux.vnet.ibm.com> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Bryan Wu <bryan.wu@canonical.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-wireless@vger.kernel.org Cc: Anton Vorontsov <cbou@mail.ru> Cc: Sangbeom Kim <sbkim73@samsung.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Avi Kivity <avi@redhat.com>
2012-08-21 01:51:24 +04:00
flush_work(&cxt->work_erase);
flush_work(&cxt->work_write);
}
static struct mtd_notifier mtdoops_notifier = {
.add = mtdoops_notify_add,
.remove = mtdoops_notify_remove,
};
static int __init mtdoops_init(void)
{
struct mtdoops_context *cxt = &oops_cxt;
int mtd_index;
char *endp;
if (strlen(mtddev) == 0) {
printk(KERN_ERR "mtdoops: mtd device (mtddev=name/number) must be supplied\n");
return -EINVAL;
}
if ((record_size & 4095) != 0) {
printk(KERN_ERR "mtdoops: record_size must be a multiple of 4096\n");
return -EINVAL;
}
if (record_size < 4096) {
printk(KERN_ERR "mtdoops: record_size must be over 4096 bytes\n");
return -EINVAL;
}
/* Setup the MTD device to use */
cxt->mtd_index = -1;
mtd_index = simple_strtoul(mtddev, &endp, 0);
if (*endp == '\0')
cxt->mtd_index = mtd_index;
cxt->oops_buf = vmalloc(record_size);
if (!cxt->oops_buf)
return -ENOMEM;
memset(cxt->oops_buf, 0xff, record_size);
cxt->oops_buf_busy = 0;
INIT_WORK(&cxt->work_erase, mtdoops_workfunc_erase);
INIT_WORK(&cxt->work_write, mtdoops_workfunc_write);
register_mtd_user(&mtdoops_notifier);
return 0;
}
static void __exit mtdoops_exit(void)
{
struct mtdoops_context *cxt = &oops_cxt;
unregister_mtd_user(&mtdoops_notifier);
vfree(cxt->oops_buf);
vfree(cxt->oops_page_used);
}
module_init(mtdoops_init);
module_exit(mtdoops_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
MODULE_DESCRIPTION("MTD Oops/Panic console logger/driver");