diff options
Diffstat (limited to 'drivers/mtd/mtdoops.c')
| -rw-r--r-- | drivers/mtd/mtdoops.c | 185 |
1 files changed, 124 insertions, 61 deletions
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c index f8af627f0b9..d3cf05012b4 100644 --- a/drivers/mtd/mtdoops.c +++ b/drivers/mtd/mtdoops.c @@ -28,19 +28,26 @@ #include <linux/workqueue.h> #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> #define OOPS_PAGE_SIZE 4096 -static struct mtdoops_context { +struct mtdoops_context { int mtd_index; - struct work_struct work; + struct work_struct work_erase; + struct work_struct work_write; struct mtd_info *mtd; int oops_pages; int nextpage; int nextcount; void *oops_buf; + + /* writecount and disabling ready are spin lock protected */ + spinlock_t writecount_lock; int ready; int writecount; } oops_cxt; @@ -62,10 +69,7 @@ static int mtdoops_erase_block(struct mtd_info *mtd, int offset) erase.mtd = mtd; erase.callback = mtdoops_erase_callback; erase.addr = offset; - if (mtd->erasesize < OOPS_PAGE_SIZE) - erase.len = OOPS_PAGE_SIZE; - else - erase.len = mtd->erasesize; + erase.len = mtd->erasesize; erase.priv = (u_long)&wait_q; set_current_state(TASK_INTERRUPTIBLE); @@ -87,7 +91,7 @@ static int mtdoops_erase_block(struct mtd_info *mtd, int offset) return 0; } -static int mtdoops_inc_counter(struct mtdoops_context *cxt) +static void mtdoops_inc_counter(struct mtdoops_context *cxt) { struct mtd_info *mtd = cxt->mtd; size_t retlen; @@ -103,25 +107,30 @@ static int mtdoops_inc_counter(struct mtdoops_context *cxt) ret = mtd->read(mtd, cxt->nextpage * OOPS_PAGE_SIZE, 4, &retlen, (u_char *) &count); - if ((retlen != 4) || (ret < 0)) { + 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); - return 1; + schedule_work(&cxt->work_erase); + return; } /* See if we need to erase the next block */ - if (count != 0xffffffff) - return 1; + 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; - return 0; } -static void mtdoops_prepare(struct mtdoops_context *cxt) +/* 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; @@ -136,8 +145,14 @@ static void mtdoops_prepare(struct mtdoops_context *cxt) cxt->nextpage = 0; } - while (mtd->block_isbad && - mtd->block_isbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE)) { + while (mtd->block_isbad) { + ret = mtd->block_isbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE); + if (!ret) + break; + if (ret < 0) { + 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); @@ -154,34 +169,72 @@ badblock: for (j = 0, ret = -1; (j < 3) && (ret < 0); j++) ret = mtdoops_erase_block(mtd, cxt->nextpage * OOPS_PAGE_SIZE); - if (ret < 0) { - if (mtd->block_markbad) - mtd->block_markbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE); - goto badblock; + if (ret >= 0) { + printk(KERN_DEBUG "mtdoops: Ready %d, %d \n", cxt->nextpage, cxt->nextcount); + cxt->ready = 1; + return; } - printk(KERN_DEBUG "mtdoops: Ready %d, %d \n", cxt->nextpage, cxt->nextcount); + if (mtd->block_markbad && (ret == -EIO)) { + ret = mtd->block_markbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE); + if (ret < 0) { + printk(KERN_ERR "mtdoops: block_markbad failed, aborting.\n"); + return; + } + } + goto badblock; +} - cxt->ready = 1; +static void mtdoops_write(struct mtdoops_context *cxt, int panic) +{ + struct mtd_info *mtd = cxt->mtd; + size_t retlen; + int ret; + + if (cxt->writecount < OOPS_PAGE_SIZE) + memset(cxt->oops_buf + cxt->writecount, 0xff, + OOPS_PAGE_SIZE - cxt->writecount); + + if (panic) + ret = mtd->panic_write(mtd, cxt->nextpage * OOPS_PAGE_SIZE, + OOPS_PAGE_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; + + 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); + + mtdoops_inc_counter(cxt); } -static void mtdoops_workfunc(struct work_struct *work) + +static void mtdoops_workfunc_write(struct work_struct *work) { struct mtdoops_context *cxt = - container_of(work, struct mtdoops_context, work); + container_of(work, struct mtdoops_context, work_write); - mtdoops_prepare(cxt); -} + mtdoops_write(cxt, 0); +} -static int find_next_position(struct mtdoops_context *cxt) +static void find_next_position(struct mtdoops_context *cxt) { struct mtd_info *mtd = cxt->mtd; - int page, maxpos = 0; + int ret, page, maxpos = 0; u32 count, maxcount = 0xffffffff; size_t retlen; for (page = 0; page < cxt->oops_pages; page++) { - mtd->read(mtd, page * OOPS_PAGE_SIZE, 4, &retlen, (u_char *) &count); + ret = mtd->read(mtd, page * 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", page * OOPS_PAGE_SIZE, retlen, ret); + continue; + } + if (count == 0xffffffff) continue; if (maxcount == 0xffffffff) { @@ -205,20 +258,19 @@ static int find_next_position(struct mtdoops_context *cxt) cxt->ready = 1; printk(KERN_DEBUG "mtdoops: Ready %d, %d (first init)\n", cxt->nextpage, cxt->nextcount); - return 0; + return; } cxt->nextpage = maxpos; cxt->nextcount = maxcount; - return mtdoops_inc_counter(cxt); + mtdoops_inc_counter(cxt); } static void mtdoops_notify_add(struct mtd_info *mtd) { struct mtdoops_context *cxt = &oops_cxt; - int ret; if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0) return; @@ -229,14 +281,18 @@ static void mtdoops_notify_add(struct mtd_info *mtd) return; } + if (mtd->erasesize < OOPS_PAGE_SIZE) { + printk(KERN_ERR "Eraseblock size of MTD partition %d too small\n", + mtd->index); + return; + } + cxt->mtd = mtd; cxt->oops_pages = mtd->size / OOPS_PAGE_SIZE; - ret = find_next_position(cxt); - if (ret == 1) - mtdoops_prepare(cxt); + find_next_position(cxt); - printk(KERN_DEBUG "mtdoops: Attached to MTD device %d\n", mtd->index); + printk(KERN_INFO "mtdoops: Attached to MTD device %d\n", mtd->index); } static void mtdoops_notify_remove(struct mtd_info *mtd) @@ -254,31 +310,28 @@ static void mtdoops_console_sync(void) { struct mtdoops_context *cxt = &oops_cxt; struct mtd_info *mtd = cxt->mtd; - size_t retlen; - int ret; + unsigned long flags; - if (!cxt->ready || !mtd) + if (!cxt->ready || !mtd || cxt->writecount == 0) return; - if (cxt->writecount == 0) + /* + * 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; - - if (cxt->writecount < OOPS_PAGE_SIZE) - memset(cxt->oops_buf + cxt->writecount, 0xff, - OOPS_PAGE_SIZE - cxt->writecount); - - ret = mtd->write(mtd, cxt->nextpage * OOPS_PAGE_SIZE, - OOPS_PAGE_SIZE, &retlen, cxt->oops_buf); + } cxt->ready = 0; - cxt->writecount = 0; - - 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); + spin_unlock_irqrestore(&cxt->writecount_lock, flags); - ret = mtdoops_inc_counter(cxt); - if (ret == 1) - schedule_work(&cxt->work); + 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 @@ -286,7 +339,7 @@ mtdoops_console_write(struct console *co, const char *s, unsigned int count) { struct mtdoops_context *cxt = co->data; struct mtd_info *mtd = cxt->mtd; - int i; + unsigned long flags; if (!oops_in_progress) { mtdoops_console_sync(); @@ -296,6 +349,13 @@ mtdoops_console_write(struct console *co, const char *s, unsigned int count) 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) + return; + if (cxt->writecount == 0) { u32 *stamp = cxt->oops_buf; *stamp = cxt->nextcount; @@ -305,10 +365,13 @@ mtdoops_console_write(struct console *co, const char *s, unsigned int count) if ((count + cxt->writecount) > OOPS_PAGE_SIZE) count = OOPS_PAGE_SIZE - cxt->writecount; - for (i = 0; i < count; i++, s++) - *((char *)(cxt->oops_buf) + cxt->writecount + i) = *s; + memcpy(cxt->oops_buf + cxt->writecount, s, count); + cxt->writecount += count; - cxt->writecount = cxt->writecount + count; + spin_unlock_irqrestore(&cxt->writecount_lock, flags); + + if (cxt->writecount == OOPS_PAGE_SIZE) + mtdoops_console_sync(); } static int __init mtdoops_console_setup(struct console *co, char *options) @@ -334,7 +397,6 @@ static struct console mtdoops_console = { .write = mtdoops_console_write, .setup = mtdoops_console_setup, .unblank = mtdoops_console_sync, - .flags = CON_PRINTBUFFER, .index = -1, .data = &oops_cxt, }; @@ -347,11 +409,12 @@ static int __init mtdoops_console_init(void) cxt->oops_buf = vmalloc(OOPS_PAGE_SIZE); if (!cxt->oops_buf) { - printk(KERN_ERR "Failed to allocate oops buffer workspace\n"); + printk(KERN_ERR "Failed to allocate mtdoops buffer workspace\n"); return -ENOMEM; } - INIT_WORK(&cxt->work, mtdoops_workfunc); + 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); |