1 files changed, 102 insertions, 77 deletions

diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index 227df24387df..b88083751a0c 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -7,6 +7,8 @@
  * Author: Richard Purdie <rpurdie@openedhand.com>
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/console.h>
@@ -16,15 +18,13 @@
 #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)
 
-#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,
@@ -40,6 +40,15 @@ 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;
 
@@ -86,9 +95,9 @@ static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset)
 
 	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);
+		pr_warn("erase of region [0x%llx, 0x%llx] on \"%s\" failed\n",
+			(unsigned long long)erase.addr,
+			(unsigned long long)erase.len, mtddev);
 		return ret;
 	}
 
@@ -99,29 +108,8 @@ static int mtdoops_erase_block(struct mtdoops_context *cxt, int offset)
 	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)
+static void mtdoops_erase(struct mtdoops_context *cxt)
 {
-	struct mtdoops_context *cxt =
-			container_of(work, struct mtdoops_context, work_erase);
 	struct mtd_info *mtd = cxt->mtd;
 	int i = 0, j, ret, mod;
 
@@ -138,20 +126,20 @@ static void mtdoops_workfunc_erase(struct work_struct *work)
 
 	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);
+		pr_warn("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");
+			pr_err("all blocks bad!\n");
 			return;
 		}
 	}
 
 	if (ret < 0) {
-		printk(KERN_ERR "mtdoops: mtd_block_isbad failed, aborting\n");
+		pr_err("mtd_block_isbad failed, aborting\n");
 		return;
 	}
 
@@ -159,41 +147,76 @@ badblock:
 		ret = mtdoops_erase_block(cxt, cxt->nextpage * record_size);
 
 	if (ret >= 0) {
-		printk(KERN_DEBUG "mtdoops: ready %d, %d\n",
-		       cxt->nextpage, cxt->nextcount);
+		pr_debug("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");
+			pr_err("block_markbad failed, aborting\n");
 			return;
 		}
 	}
 	goto badblock;
 }
 
+/* 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);
+	mtdoops_erase(cxt);
+}
+
+static void mtdoops_inc_counter(struct mtdoops_context *cxt, int panic)
+{
+	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)) {
+		pr_debug("not ready %d, %d (erase %s)\n",
+			 cxt->nextpage, cxt->nextcount,
+			 panic ? "immediately" : "scheduled");
+		if (panic) {
+			/* In case of panic, erase immediately */
+			mtdoops_erase(cxt);
+		} else {
+			/* Otherwise, schedule work to erase it "nicely" */
+			schedule_work(&cxt->work_erase);
+		}
+	} else {
+		pr_debug("ready %d, %d (no erase)\n",
+			 cxt->nextpage, cxt->nextcount);
+	}
+}
+
 static void mtdoops_write(struct mtdoops_context *cxt, int panic)
 {
 	struct mtd_info *mtd = cxt->mtd;
 	size_t retlen;
-	u32 *hdr;
+	struct mtdoops_hdr *hdr;
 	int ret;
 
 	if (test_and_set_bit(0, &cxt->oops_buf_busy))
 		return;
 
 	/* Add mtdoops header to the buffer */
-	hdr = cxt->oops_buf;
-	hdr[0] = cxt->nextcount;
-	hdr[1] = MTDOOPS_KERNMSG_MAGIC;
+	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");
+			pr_err("Cannot write from panic without panic_write\n");
 			goto out;
 		}
 	} else
@@ -201,12 +224,12 @@ static void mtdoops_write(struct mtdoops_context *cxt, int panic)
 				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",
+		pr_err("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);
+	mtdoops_inc_counter(cxt, panic);
 out:
 	clear_bit(0, &cxt->oops_buf_busy);
 }
@@ -222,8 +245,9 @@ static void mtdoops_workfunc_write(struct work_struct *work)
 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 count[2], maxcount = 0xffffffff;
+	u32 maxcount = 0xffffffff;
 	size_t retlen;
 
 	for (page = 0; page < cxt->oops_pages; page++) {
@@ -231,32 +255,33 @@ static void find_next_position(struct mtdoops_context *cxt)
 			continue;
 		/* 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 = 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 (%td of %d read), err %d\n",
-			       page * record_size, retlen,
-			       MTDOOPS_HEADER_SIZE, ret);
+			pr_err("read failure at %ld (%zu of %zu read), err %d\n",
+			       page * record_size, retlen, sizeof(hdr), ret);
 			continue;
 		}
 
-		if (count[0] == 0xffffffff && count[1] == 0xffffffff)
+		if (hdr.seq == 0xffffffff && hdr.magic == 0xffffffff)
 			mark_page_unused(cxt, page);
-		if (count[0] == 0xffffffff || count[1] != MTDOOPS_KERNMSG_MAGIC)
+		if (hdr.seq == 0xffffffff ||
+		    (hdr.magic != MTDOOPS_KERNMSG_MAGIC_v1 &&
+		     hdr.magic != MTDOOPS_KERNMSG_MAGIC_v2))
 			continue;
 		if (maxcount == 0xffffffff) {
-			maxcount = count[0];
+			maxcount = hdr.seq;
 			maxpos = page;
-		} else if (count[0] < 0x40000000 && maxcount > 0xc0000000) {
-			maxcount = count[0];
+		} else if (hdr.seq < 0x40000000 && maxcount > 0xc0000000) {
+			maxcount = hdr.seq;
 			maxpos = page;
-		} else if (count[0] > maxcount && count[0] < 0xc0000000) {
-			maxcount = count[0];
+		} else if (hdr.seq > maxcount && hdr.seq < 0xc0000000) {
+			maxcount = hdr.seq;
 			maxpos = page;
-		} else if (count[0] > maxcount && count[0] > 0xc0000000
+		} else if (hdr.seq > maxcount && hdr.seq > 0xc0000000
 					&& maxcount > 0x80000000) {
-			maxcount = count[0];
+			maxcount = hdr.seq;
 			maxpos = page;
 		}
 	}
@@ -269,29 +294,30 @@ static void find_next_position(struct mtdoops_context *cxt)
 		cxt->nextcount = maxcount;
 	}
 
-	mtdoops_inc_counter(cxt);
+	mtdoops_inc_counter(cxt, 0);
 }
 
 static void mtdoops_do_dump(struct kmsg_dumper *dumper,
-			    enum kmsg_dump_reason reason)
+			    struct kmsg_dump_detail *detail)
 {
 	struct mtdoops_context *cxt = container_of(dumper,
 			struct mtdoops_context, dump);
 	struct kmsg_dump_iter iter;
 
 	/* Only dump oopses if dump_oops is set */
-	if (reason == KMSG_DUMP_OOPS && !dump_oops)
+	if (detail->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 + MTDOOPS_HEADER_SIZE,
-			     record_size - MTDOOPS_HEADER_SIZE, NULL);
+	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) {
+	if (detail->reason != KMSG_DUMP_OOPS) {
 		/* Panics must be written immediately */
 		mtdoops_write(cxt, 1);
 	} else {
@@ -313,28 +339,27 @@ static void mtdoops_notify_add(struct mtd_info *mtd)
 		return;
 
 	if (mtd->size < mtd->erasesize * 2) {
-		printk(KERN_ERR "mtdoops: MTD partition %d not big enough for mtdoops\n",
+		pr_err("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",
+		pr_err("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",
+		pr_err("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 */
 	cxt->oops_page_used =
-		vmalloc(array_size(sizeof(unsigned long),
-				   DIV_ROUND_UP(mtdoops_pages,
-						BITS_PER_LONG)));
+		vmalloc_array(DIV_ROUND_UP(mtdoops_pages, BITS_PER_LONG),
+			      sizeof(unsigned long));
 	if (!cxt->oops_page_used) {
-		printk(KERN_ERR "mtdoops: could not allocate page array\n");
+		pr_err("could not allocate page array\n");
 		return;
 	}
 
@@ -342,7 +367,7 @@ static void mtdoops_notify_add(struct mtd_info *mtd)
 	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);
+		pr_err("registering kmsg dumper failed, error %d\n", err);
 		vfree(cxt->oops_page_used);
 		cxt->oops_page_used = NULL;
 		return;
@@ -351,7 +376,7 @@ static void mtdoops_notify_add(struct mtd_info *mtd)
 	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);
+	pr_info("Attached to MTD device %d\n", mtd->index);
 }
 
 static void mtdoops_notify_remove(struct mtd_info *mtd)
@@ -362,7 +387,7 @@ static void mtdoops_notify_remove(struct mtd_info *mtd)
 		return;
 
 	if (kmsg_dump_unregister(&cxt->dump) < 0)
-		printk(KERN_WARNING "mtdoops: could not unregister kmsg_dumper\n");
+		pr_warn("could not unregister kmsg_dumper\n");
 
 	cxt->mtd = NULL;
 	flush_work(&cxt->work_erase);
@@ -382,15 +407,15 @@ static int __init mtdoops_init(void)
 	char *endp;
 
 	if (strlen(mtddev) == 0) {
-		printk(KERN_ERR "mtdoops: mtd device (mtddev=name/number) must be supplied\n");
+		pr_err("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");
+		pr_err("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");
+		pr_err("record_size must be over 4096 bytes\n");
 		return -EINVAL;
 	}