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Diffstat (limited to 'drivers/mtd/mtdoops.c')
-rw-r--r--drivers/mtd/mtdoops.c389
1 files changed, 200 insertions, 189 deletions
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index 1060337..a714ec4 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -29,14 +29,34 @@
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/delay.h>
-#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/mtd/mtd.h>
+#include <linux/kmsg_dump.h>
+
+/* Maximum MTD partition size */
+#define MTDOOPS_MAX_MTD_SIZE (8 * 1024 * 1024)
#define MTDOOPS_KERNMSG_MAGIC 0x5d005d00
-#define OOPS_PAGE_SIZE 4096
+#define MTDOOPS_HEADER_SIZE 8
+
+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)");
static struct mtdoops_context {
+ struct kmsg_dumper dump;
+
int mtd_index;
struct work_struct work_erase;
struct work_struct work_write;
@@ -44,28 +64,43 @@ static struct mtdoops_context {
int oops_pages;
int nextpage;
int nextcount;
- char *name;
+ unsigned long *oops_page_used;
void *oops_buf;
-
- /* writecount and disabling ready are spin lock protected */
- spinlock_t writecount_lock;
- int ready;
- int writecount;
} 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 void mtdoops_erase_callback(struct erase_info *done)
{
wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv;
wake_up(wait_q);
}
-static int mtdoops_erase_block(struct mtd_info *mtd, int offset)
+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;
DECLARE_WAITQUEUE(wait, current);
wait_queue_head_t wait_q;
int ret;
+ int page;
init_waitqueue_head(&wait_q);
erase.mtd = mtd;
@@ -81,25 +116,24 @@ static int mtdoops_erase_block(struct mtd_info *mtd, int offset)
if (ret) {
set_current_state(TASK_RUNNING);
remove_wait_queue(&wait_q, &wait);
- 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, mtd->name);
+ 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;
}
schedule(); /* Wait for erase to finish. */
remove_wait_queue(&wait_q, &wait);
+ /* 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)
{
- struct mtd_info *mtd = cxt->mtd;
- size_t retlen;
- u32 count;
- int ret;
-
cxt->nextpage++;
if (cxt->nextpage >= cxt->oops_pages)
cxt->nextpage = 0;
@@ -107,25 +141,13 @@ static void mtdoops_inc_counter(struct mtdoops_context *cxt)
if (cxt->nextcount == 0xffffffff)
cxt->nextcount = 0;
- ret = mtd->read(mtd, cxt->nextpage * OOPS_PAGE_SIZE, 4,
- &retlen, (u_char *) &count);
- if ((retlen != 4) || ((ret < 0) && (ret != -EUCLEAN))) {
- printk(KERN_ERR "mtdoops: Read failure at %d (%td of 4 read)"
- ", err %d.\n", cxt->nextpage * OOPS_PAGE_SIZE,
- retlen, ret);
+ if (page_is_used(cxt, cxt->nextpage)) {
schedule_work(&cxt->work_erase);
return;
}
- /* See if we need to erase the next block */
- if (count != 0xffffffff) {
- schedule_work(&cxt->work_erase);
- return;
- }
-
- printk(KERN_DEBUG "mtdoops: Ready %d, %d (no erase)\n",
- cxt->nextpage, cxt->nextcount);
- cxt->ready = 1;
+ 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 */
@@ -140,47 +162,47 @@ static void mtdoops_workfunc_erase(struct work_struct *work)
if (!mtd)
return;
- mod = (cxt->nextpage * OOPS_PAGE_SIZE) % mtd->erasesize;
+ mod = (cxt->nextpage * record_size) % mtd->erasesize;
if (mod != 0) {
- cxt->nextpage = cxt->nextpage + ((mtd->erasesize - mod) / OOPS_PAGE_SIZE);
+ cxt->nextpage = cxt->nextpage + ((mtd->erasesize - mod) / record_size);
if (cxt->nextpage >= cxt->oops_pages)
cxt->nextpage = 0;
}
while (mtd->block_isbad) {
- ret = mtd->block_isbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE);
+ ret = mtd->block_isbad(mtd, cxt->nextpage * record_size);
if (!ret)
break;
if (ret < 0) {
- printk(KERN_ERR "mtdoops: block_isbad failed, aborting.\n");
+ printk(KERN_ERR "mtdoops: block_isbad failed, aborting\n");
return;
}
badblock:
- printk(KERN_WARNING "mtdoops: Bad block at %08x\n",
- cxt->nextpage * OOPS_PAGE_SIZE);
+ printk(KERN_WARNING "mtdoops: bad block at %08lx\n",
+ cxt->nextpage * record_size);
i++;
- cxt->nextpage = cxt->nextpage + (mtd->erasesize / OOPS_PAGE_SIZE);
+ cxt->nextpage = cxt->nextpage + (mtd->erasesize / record_size);
if (cxt->nextpage >= cxt->oops_pages)
cxt->nextpage = 0;
- if (i == (cxt->oops_pages / (mtd->erasesize / OOPS_PAGE_SIZE))) {
- printk(KERN_ERR "mtdoops: All blocks bad!\n");
+ if (i == cxt->oops_pages / (mtd->erasesize / record_size)) {
+ printk(KERN_ERR "mtdoops: all blocks bad!\n");
return;
}
}
for (j = 0, ret = -1; (j < 3) && (ret < 0); j++)
- ret = mtdoops_erase_block(mtd, cxt->nextpage * OOPS_PAGE_SIZE);
+ ret = mtdoops_erase_block(cxt, cxt->nextpage * record_size);
if (ret >= 0) {
- printk(KERN_DEBUG "mtdoops: Ready %d, %d \n", cxt->nextpage, cxt->nextcount);
- cxt->ready = 1;
+ printk(KERN_DEBUG "mtdoops: ready %d, %d\n",
+ cxt->nextpage, cxt->nextcount);
return;
}
- if (mtd->block_markbad && (ret == -EIO)) {
- ret = mtd->block_markbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE);
+ if (mtd->block_markbad && ret == -EIO) {
+ ret = mtd->block_markbad(mtd, cxt->nextpage * record_size);
if (ret < 0) {
- printk(KERN_ERR "mtdoops: block_markbad failed, aborting.\n");
+ printk(KERN_ERR "mtdoops: block_markbad failed, aborting\n");
return;
}
}
@@ -191,36 +213,37 @@ static void mtdoops_write(struct mtdoops_context *cxt, int panic)
{
struct mtd_info *mtd = cxt->mtd;
size_t retlen;
+ u32 *hdr;
int ret;
- if (cxt->writecount < OOPS_PAGE_SIZE)
- memset(cxt->oops_buf + cxt->writecount, 0xff,
- OOPS_PAGE_SIZE - cxt->writecount);
+ /* Add mtdoops header to the buffer */
+ hdr = cxt->oops_buf;
+ hdr[0] = cxt->nextcount;
+ hdr[1] = MTDOOPS_KERNMSG_MAGIC;
if (panic)
- ret = mtd->panic_write(mtd, cxt->nextpage * OOPS_PAGE_SIZE,
- OOPS_PAGE_SIZE, &retlen, cxt->oops_buf);
+ ret = mtd->panic_write(mtd, cxt->nextpage * record_size,
+ record_size, &retlen, cxt->oops_buf);
else
- ret = mtd->write(mtd, cxt->nextpage * OOPS_PAGE_SIZE,
- OOPS_PAGE_SIZE, &retlen, cxt->oops_buf);
-
- cxt->writecount = 0;
+ ret = mtd->write(mtd, cxt->nextpage * record_size,
+ record_size, &retlen, cxt->oops_buf);
- if ((retlen != OOPS_PAGE_SIZE) || (ret < 0))
- printk(KERN_ERR "mtdoops: Write failure at %d (%td of %d written), err %d.\n",
- cxt->nextpage * OOPS_PAGE_SIZE, retlen, OOPS_PAGE_SIZE, ret);
+ 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);
}
-
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)
{
@@ -230,28 +253,33 @@ static void find_next_position(struct mtdoops_context *cxt)
size_t retlen;
for (page = 0; page < cxt->oops_pages; page++) {
- ret = mtd->read(mtd, page * OOPS_PAGE_SIZE, 8, &retlen, (u_char *) &count[0]);
- if ((retlen != 8) || ((ret < 0) && (ret != -EUCLEAN))) {
- printk(KERN_ERR "mtdoops: Read failure at %d (%td of 8 read)"
- ", err %d.\n", page * OOPS_PAGE_SIZE, retlen, ret);
+ /* Assume the page is used */
+ mark_page_used(cxt, page);
+ ret = mtd->read(mtd, page * record_size, MTDOOPS_HEADER_SIZE,
+ &retlen, (u_char *) &count[0]);
+ if (retlen != MTDOOPS_HEADER_SIZE ||
+ (ret < 0 && ret != -EUCLEAN)) {
+ printk(KERN_ERR "mtdoops: read failure at %ld (%td of %d read), err %d\n",
+ page * record_size, retlen,
+ MTDOOPS_HEADER_SIZE, ret);
continue;
}
- if (count[1] != MTDOOPS_KERNMSG_MAGIC)
- continue;
+ if (count[0] == 0xffffffff && count[1] == 0xffffffff)
+ mark_page_unused(cxt, page);
if (count[0] == 0xffffffff)
continue;
if (maxcount == 0xffffffff) {
maxcount = count[0];
maxpos = page;
- } else if ((count[0] < 0x40000000) && (maxcount > 0xc0000000)) {
+ } else if (count[0] < 0x40000000 && maxcount > 0xc0000000) {
maxcount = count[0];
maxpos = page;
- } else if ((count[0] > maxcount) && (count[0] < 0xc0000000)) {
+ } else if (count[0] > maxcount && count[0] < 0xc0000000) {
maxcount = count[0];
maxpos = page;
- } else if ((count[0] > maxcount) && (count[0] > 0xc0000000)
- && (maxcount > 0x80000000)) {
+ } else if (count[0] > maxcount && count[0] > 0xc0000000
+ && maxcount > 0x80000000) {
maxcount = count[0];
maxpos = page;
}
@@ -269,187 +297,170 @@ static void find_next_position(struct mtdoops_context *cxt)
mtdoops_inc_counter(cxt);
}
-
-static void mtdoops_notify_add(struct mtd_info *mtd)
+static void mtdoops_do_dump(struct kmsg_dumper *dumper,
+ enum kmsg_dump_reason reason, const char *s1, unsigned long l1,
+ const char *s2, unsigned long l2)
{
- struct mtdoops_context *cxt = &oops_cxt;
+ struct mtdoops_context *cxt = container_of(dumper,
+ struct mtdoops_context, dump);
+ unsigned long s1_start, s2_start;
+ unsigned long l1_cpy, l2_cpy;
+ char *dst;
+
+ /* Only dump oopses if dump_oops is set */
+ if (reason == KMSG_DUMP_OOPS && !dump_oops)
+ return;
- if (cxt->name && !strcmp(mtd->name, cxt->name))
- cxt->mtd_index = mtd->index;
+ dst = cxt->oops_buf + MTDOOPS_HEADER_SIZE; /* Skip the header */
+ l2_cpy = min(l2, record_size - MTDOOPS_HEADER_SIZE);
+ l1_cpy = min(l1, record_size - MTDOOPS_HEADER_SIZE - l2_cpy);
- if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0)
- return;
+ s2_start = l2 - l2_cpy;
+ s1_start = l1 - l1_cpy;
- if (mtd->size < (mtd->erasesize * 2)) {
- printk(KERN_ERR "MTD partition %d not big enough for mtdoops\n",
- mtd->index);
- return;
- }
+ memcpy(dst, s1 + s1_start, l1_cpy);
+ memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy);
- if (mtd->erasesize < OOPS_PAGE_SIZE) {
- printk(KERN_ERR "Eraseblock size of MTD partition %d too small\n",
- mtd->index);
+ /* Panics must be written immediately */
+ if (reason == KMSG_DUMP_PANIC) {
+ if (!cxt->mtd->panic_write)
+ printk(KERN_ERR "mtdoops: Cannot write from panic without panic_write\n");
+ else
+ mtdoops_write(cxt, 1);
return;
}
- cxt->mtd = mtd;
- if (mtd->size > INT_MAX)
- cxt->oops_pages = INT_MAX / OOPS_PAGE_SIZE;
- else
- cxt->oops_pages = (int)mtd->size / OOPS_PAGE_SIZE;
-
- find_next_position(cxt);
-
- printk(KERN_INFO "mtdoops: Attached to MTD device %d\n", mtd->index);
+ /* For other cases, schedule work to write it "nicely" */
+ schedule_work(&cxt->work_write);
}
-static void mtdoops_notify_remove(struct mtd_info *mtd)
+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 ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0)
- return;
-
- cxt->mtd = NULL;
- flush_scheduled_work();
-}
-
-static void mtdoops_console_sync(void)
-{
- struct mtdoops_context *cxt = &oops_cxt;
- struct mtd_info *mtd = cxt->mtd;
- unsigned long flags;
+ if (!strcmp(mtd->name, mtddev))
+ cxt->mtd_index = mtd->index;
- if (!cxt->ready || !mtd || cxt->writecount == 0)
+ if (mtd->index != cxt->mtd_index || cxt->mtd_index < 0)
return;
- /*
- * Once ready is 0 and we've held the lock no further writes to the
- * buffer will happen
- */
- spin_lock_irqsave(&cxt->writecount_lock, flags);
- if (!cxt->ready) {
- spin_unlock_irqrestore(&cxt->writecount_lock, flags);
+ if (mtd->size < mtd->erasesize * 2) {
+ printk(KERN_ERR "mtdoops: MTD partition %d not big enough for mtdoops\n",
+ mtd->index);
return;
}
- cxt->ready = 0;
- spin_unlock_irqrestore(&cxt->writecount_lock, flags);
-
- if (mtd->panic_write && in_interrupt())
- /* Interrupt context, we're going to panic so try and log */
- mtdoops_write(cxt, 1);
- else
- schedule_work(&cxt->work_write);
-}
-
-static void
-mtdoops_console_write(struct console *co, const char *s, unsigned int count)
-{
- struct mtdoops_context *cxt = co->data;
- struct mtd_info *mtd = cxt->mtd;
- unsigned long flags;
-
- if (!oops_in_progress) {
- mtdoops_console_sync();
+ if (mtd->erasesize < record_size) {
+ printk(KERN_ERR "mtdoops: eraseblock size of MTD partition %d too small\n",
+ mtd->index);
return;
}
-
- if (!cxt->ready || !mtd)
+ 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;
+ }
- /* Locking on writecount ensures sequential writes to the buffer */
- spin_lock_irqsave(&cxt->writecount_lock, flags);
-
- /* Check ready status didn't change whilst waiting for the lock */
- if (!cxt->ready) {
- spin_unlock_irqrestore(&cxt->writecount_lock, flags);
+ /* oops_page_used is a bit field */
+ cxt->oops_page_used = vmalloc(DIV_ROUND_UP(mtdoops_pages,
+ BITS_PER_LONG));
+ if (!cxt->oops_page_used) {
+ printk(KERN_ERR "mtdoops: could not allocate page array\n");
return;
}
- if (cxt->writecount == 0) {
- u32 *stamp = cxt->oops_buf;
- *stamp++ = cxt->nextcount;
- *stamp = MTDOOPS_KERNMSG_MAGIC;
- cxt->writecount = 8;
+ 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;
}
- if ((count + cxt->writecount) > OOPS_PAGE_SIZE)
- count = OOPS_PAGE_SIZE - cxt->writecount;
-
- memcpy(cxt->oops_buf + cxt->writecount, s, count);
- cxt->writecount += count;
-
- spin_unlock_irqrestore(&cxt->writecount_lock, flags);
-
- if (cxt->writecount == OOPS_PAGE_SIZE)
- mtdoops_console_sync();
+ 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 int __init mtdoops_console_setup(struct console *co, char *options)
+static void mtdoops_notify_remove(struct mtd_info *mtd)
{
- struct mtdoops_context *cxt = co->data;
+ struct mtdoops_context *cxt = &oops_cxt;
- if (cxt->mtd_index != -1 || cxt->name)
- return -EBUSY;
- if (options) {
- cxt->name = kstrdup(options, GFP_KERNEL);
- return 0;
- }
- if (co->index == -1)
- return -EINVAL;
+ if (mtd->index != cxt->mtd_index || cxt->mtd_index < 0)
+ return;
- cxt->mtd_index = co->index;
- return 0;
+ if (kmsg_dump_unregister(&cxt->dump) < 0)
+ printk(KERN_WARNING "mtdoops: could not unregister kmsg_dumper\n");
+
+ cxt->mtd = NULL;
+ flush_scheduled_work();
}
+
static struct mtd_notifier mtdoops_notifier = {
.add = mtdoops_notify_add,
.remove = mtdoops_notify_remove,
};
-static struct console mtdoops_console = {
- .name = "ttyMTD",
- .write = mtdoops_console_write,
- .setup = mtdoops_console_setup,
- .unblank = mtdoops_console_sync,
- .index = -1,
- .data = &oops_cxt,
-};
-
-static int __init mtdoops_console_init(void)
+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;
- cxt->oops_buf = vmalloc(OOPS_PAGE_SIZE);
- spin_lock_init(&cxt->writecount_lock);
+ mtd_index = simple_strtoul(mtddev, &endp, 0);
+ if (*endp == '\0')
+ cxt->mtd_index = mtd_index;
+ if (cxt->mtd_index > MAX_MTD_DEVICES) {
+ printk(KERN_ERR "mtdoops: invalid mtd device number (%u) given\n",
+ mtd_index);
+ return -EINVAL;
+ }
+ cxt->oops_buf = vmalloc(record_size);
if (!cxt->oops_buf) {
- printk(KERN_ERR "Failed to allocate mtdoops buffer workspace\n");
+ printk(KERN_ERR "mtdoops: failed to allocate buffer workspace\n");
return -ENOMEM;
}
+ memset(cxt->oops_buf, 0xff, record_size);
INIT_WORK(&cxt->work_erase, mtdoops_workfunc_erase);
INIT_WORK(&cxt->work_write, mtdoops_workfunc_write);
- register_console(&mtdoops_console);
register_mtd_user(&mtdoops_notifier);
return 0;
}
-static void __exit mtdoops_console_exit(void)
+static void __exit mtdoops_exit(void)
{
struct mtdoops_context *cxt = &oops_cxt;
unregister_mtd_user(&mtdoops_notifier);
- unregister_console(&mtdoops_console);
- kfree(cxt->name);
vfree(cxt->oops_buf);
+ vfree(cxt->oops_page_used);
}
-subsys_initcall(mtdoops_console_init);
-module_exit(mtdoops_console_exit);
+module_init(mtdoops_init);
+module_exit(mtdoops_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
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