diff options
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/mtdoops.c | 235 |
1 files changed, 102 insertions, 133 deletions
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c index 64772dc0ea2..a714ec48276 100644 --- a/drivers/mtd/mtdoops.c +++ b/drivers/mtd/mtdoops.c @@ -29,21 +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 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; @@ -52,14 +65,8 @@ static struct mtdoops_context { int nextpage; int nextcount; unsigned long *oops_page_used; - char *name; 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) @@ -111,7 +118,7 @@ static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset) 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); + (unsigned long long)erase.len, mtddev); return ret; } @@ -141,7 +148,6 @@ static void mtdoops_inc_counter(struct mtdoops_context *cxt) printk(KERN_DEBUG "mtdoops: ready %d, %d (no erase)\n", cxt->nextpage, cxt->nextcount); - cxt->ready = 1; } /* Scheduled work - when we can't proceed without erasing a block */ @@ -190,7 +196,6 @@ badblock: if (ret >= 0) { printk(KERN_DEBUG "mtdoops: ready %d, %d\n", cxt->nextpage, cxt->nextcount); - cxt->ready = 1; return; } @@ -208,11 +213,13 @@ 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 < record_size) - memset(cxt->oops_buf + cxt->writecount, 0xff, - record_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 * record_size, @@ -221,17 +228,15 @@ static void mtdoops_write(struct mtdoops_context *cxt, int panic) ret = mtd->write(mtd, cxt->nextpage * record_size, record_size, &retlen, cxt->oops_buf); - cxt->writecount = 0; - 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 = @@ -250,17 +255,18 @@ static void find_next_position(struct mtdoops_context *cxt) for (page = 0; page < cxt->oops_pages; page++) { /* Assume the page is used */ mark_page_used(cxt, page); - ret = mtd->read(mtd, page * record_size, 8, &retlen, (u_char *) &count[0]); - if (retlen != 8 || (ret < 0 && ret != -EUCLEAN)) { - printk(KERN_ERR "mtdoops: read failure at %ld (%td of 8 read), err %d\n", - page * record_size, retlen, ret); + 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[0] == 0xffffffff && count[1] == 0xffffffff) mark_page_unused(cxt, page); - if (count[1] != MTDOOPS_KERNMSG_MAGIC) - continue; if (count[0] == 0xffffffff) continue; if (maxcount == 0xffffffff) { @@ -291,15 +297,50 @@ static void find_next_position(struct mtdoops_context *cxt) mtdoops_inc_counter(cxt); } +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 = 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; + + 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); + + s2_start = l2 - l2_cpy; + s1_start = l1 - l1_cpy; + + memcpy(dst, s1 + s1_start, l1_cpy); + memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy); + + /* 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; + } + + /* 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 = mtd->size; - - do_div(mtdoops_pages, record_size); + u64 mtdoops_pages = div_u64(mtd->size, record_size); + int err; - if (cxt->name && !strcmp(mtd->name, cxt->name)) + if (!strcmp(mtd->name, mtddev)) cxt->mtd_index = mtd->index; if (mtd->index != cxt->mtd_index || cxt->mtd_index < 0) @@ -310,13 +351,11 @@ static void mtdoops_notify_add(struct mtd_info *mtd) 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); @@ -327,7 +366,16 @@ static void mtdoops_notify_add(struct mtd_info *mtd) cxt->oops_page_used = vmalloc(DIV_ROUND_UP(mtdoops_pages, BITS_PER_LONG)); if (!cxt->oops_page_used) { - printk(KERN_ERR "Could not allocate page array\n"); + printk(KERN_ERR "mtdoops: could not allocate page array\n"); + return; + } + + 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; } @@ -344,116 +392,29 @@ static void mtdoops_notify_remove(struct mtd_info *mtd) 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; 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 (!cxt->ready || !mtd || cxt->writecount == 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); - 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(); - return; - } - - if (!cxt->ready || !mtd) - 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); - return; - } - - if (cxt->writecount == 0) { - u32 *stamp = cxt->oops_buf; - *stamp++ = cxt->nextcount; - *stamp = MTDOOPS_KERNMSG_MAGIC; - cxt->writecount = 8; - } - - if (count + cxt->writecount > record_size) - count = record_size - cxt->writecount; - - memcpy(cxt->oops_buf + cxt->writecount, s, count); - cxt->writecount += count; - - spin_unlock_irqrestore(&cxt->writecount_lock, flags); - - if (cxt->writecount == record_size) - mtdoops_console_sync(); -} - -static int __init mtdoops_console_setup(struct console *co, char *options) -{ - struct mtdoops_context *cxt = co->data; - - 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; - - cxt->mtd_index = co->index; - return 0; -} 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; @@ -462,36 +423,44 @@ static int __init mtdoops_console_init(void) 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; + 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 "mtdoops: failed to allocate buffer workspace\n"); return -ENOMEM; } + memset(cxt->oops_buf, 0xff, record_size); - spin_lock_init(&cxt->writecount_lock); 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>"); |