[MTD] Add sync/unblank function to mtdoops
Richard Purdie [Tue, 10 Jul 2007 19:33:54 +0000 (20:33 +0100)]
mtdoops wasn't ensuring data was flushed to flash in crash situations
after recent changes in mainline kernels as tracking the
oops_in_progress variable was no longer enough. We can use the "unblank"
console call as a sync call to tell us to write out the buffer though.

Therefore add a sync function to mtdoops and call this when console
unblank events occur.

Signed-off-by: Richard Purdie <rpurdie@openedhand.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

drivers/mtd/mtdoops.c

index cfc28ab..62ee204 100644 (file)
@@ -250,40 +250,50 @@ static void mtdoops_notify_remove(struct mtd_info *mtd)
        flush_scheduled_work();
 }
 
-
-static void
-mtdoops_console_write(struct console *co, const char *s, unsigned int count)
+static void mtdoops_console_sync(void)
 {
-       struct mtdoops_context *cxt = co->data;
+       struct mtdoops_context *cxt = &oops_cxt;
        struct mtd_info *mtd = cxt->mtd;
-       int i, ret;
+       size_t retlen;
+       int ret;
 
        if (!cxt->ready || !mtd)
                return;
 
-       if (!oops_in_progress && cxt->writecount != 0) {
-               size_t retlen;
-               if (cxt->writecount < OOPS_PAGE_SIZE)
-                       memset(cxt->oops_buf + cxt->writecount, 0xff,
+       if (cxt->writecount == 0)
+               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,
+       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 (%d of %d"
-                               " written), err %d.\n",
-                               cxt->nextpage * OOPS_PAGE_SIZE, retlen,
-                               OOPS_PAGE_SIZE, ret);
-
-               ret = mtdoops_inc_counter(cxt);
-               if (ret == 1)
-                       schedule_work(&cxt->work);
+       cxt->ready = 0;
+       cxt->writecount = 0;
+
+       if ((retlen != OOPS_PAGE_SIZE) || (ret < 0))
+               printk(KERN_ERR "mtdoops: Write failure at %d (%d of %d written), err %d.\n",
+                       cxt->nextpage * OOPS_PAGE_SIZE, retlen, OOPS_PAGE_SIZE, ret);
+
+       ret = mtdoops_inc_counter(cxt);
+       if (ret == 1)
+               schedule_work(&cxt->work);
+}
+
+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;
+       int i;
+
+       if (!oops_in_progress) {
+               mtdoops_console_sync();
+               return;
        }
 
-       if (!oops_in_progress)
+       if (!cxt->ready || !mtd)
                return;
 
        if (cxt->writecount == 0) {
@@ -323,6 +333,7 @@ static struct console mtdoops_console = {
        .name           = "ttyMTD",
        .write          = mtdoops_console_write,
        .setup          = mtdoops_console_setup,
+       .unblank        = mtdoops_console_sync,
        .flags          = CON_PRINTBUFFER,
        .index          = -1,
        .data           = &oops_cxt,