1 files changed, 126 insertions, 59 deletions

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index 5ca560c968..d638f700d0 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -13,6 +13,29 @@
 
 #define MTD_NAME_MAX_LEN 20
 
+void board_mtdparts_default(const char **mtdids, const char **mtdparts);
+
+static const char *get_mtdids(void)
+{
+	__maybe_unused const char *mtdparts = NULL;
+	const char *mtdids = env_get("mtdids");
+
+	if (mtdids)
+		return mtdids;
+
+#if defined(CONFIG_SYS_MTDPARTS_RUNTIME)
+	board_mtdparts_default(&mtdids, &mtdparts);
+#elif defined(MTDIDS_DEFAULT)
+	mtdids = MTDIDS_DEFAULT;
+#elif defined(CONFIG_MTDIDS_DEFAULT)
+	mtdids = CONFIG_MTDIDS_DEFAULT;
+#endif
+
+	if (mtdids)
+		env_set("mtdids", mtdids);
+
+	return mtdids;
+}
 
 /**
  * mtd_search_alternate_name - Search an alternate name for @mtdname thanks to
@@ -34,7 +57,7 @@ int mtd_search_alternate_name(const char *mtdname, char *altname,
 	const char *mtdids, *equal, *comma, *dev_id, *mtd_id;
 	int dev_id_len, mtd_id_len;
 
-	mtdids = env_get("mtdids");
+	mtdids = get_mtdids();
 	if (!mtdids)
 		return -EINVAL;
 
@@ -92,30 +115,6 @@ static void mtd_probe_uclass_mtd_devs(void) { }
 #endif
 
 #if defined(CONFIG_MTD_PARTITIONS)
-extern void board_mtdparts_default(const char **mtdids,
-				   const char **mtdparts);
-
-static const char *get_mtdids(void)
-{
-	__maybe_unused const char *mtdparts = NULL;
-	const char *mtdids = env_get("mtdids");
-
-	if (mtdids)
-		return mtdids;
-
-#if defined(CONFIG_SYS_MTDPARTS_RUNTIME)
-	board_mtdparts_default(&mtdids, &mtdparts);
-#elif defined(MTDIDS_DEFAULT)
-	mtdids = MTDIDS_DEFAULT;
-#elif defined(CONFIG_MTDIDS_DEFAULT)
-	mtdids = CONFIG_MTDIDS_DEFAULT;
-#endif
-
-	if (mtdids)
-		env_set("mtdids", mtdids);
-
-	return mtdids;
-}
 
 #define MTDPARTS_MAXLEN         512
 
@@ -150,20 +149,74 @@ static const char *get_mtdparts(void)
 	return mtdparts;
 }
 
+static int mtd_del_parts(struct mtd_info *mtd, bool quiet)
+{
+	int ret;
+
+	if (!mtd_has_partitions(mtd))
+		return 0;
+
+	/* do not delete partitions if they are in use. */
+	if (mtd_partitions_used(mtd)) {
+		if (!quiet)
+			printf("\"%s\" partitions still in use, can't delete them\n",
+			       mtd->name);
+		return -EACCES;
+	}
+
+	ret = del_mtd_partitions(mtd);
+	if (ret)
+		return ret;
+
+	return 1;
+}
+
+static bool mtd_del_all_parts_failed;
+
+static void mtd_del_all_parts(void)
+{
+	struct mtd_info *mtd;
+	int ret = 0;
+
+	mtd_del_all_parts_failed = false;
+
+	/*
+	 * It is not safe to remove entries from the mtd_for_each_device loop
+	 * as it uses idr indexes and the partitions removal is done in bulk
+	 * (all partitions of one device at the same time), so break and
+	 * iterate from start each time a new partition is found and deleted.
+	 */
+	do {
+		mtd_for_each_device(mtd) {
+			ret = mtd_del_parts(mtd, false);
+			if (ret > 0)
+				break;
+			else if (ret < 0)
+				mtd_del_all_parts_failed = true;
+		}
+	} while (ret > 0);
+}
+
 int mtd_probe_devices(void)
 {
 	static char *old_mtdparts;
 	static char *old_mtdids;
 	const char *mtdparts = get_mtdparts();
 	const char *mtdids = get_mtdids();
-	bool remaining_partitions = true;
+	const char *mtdparts_next = mtdparts;
 	struct mtd_info *mtd;
 
 	mtd_probe_uclass_mtd_devs();
 
-	/* Check if mtdparts/mtdids changed since last call, otherwise: exit */
+	/*
+	 * Check if mtdparts/mtdids changed, if the MTD dev list was updated
+	 * or if our previous attempt to delete existing partititions failed.
+	 * In any of these cases we want to update the partitions, otherwise,
+	 * everything is up-to-date and we can return 0 directly.
+	 */
 	if ((!mtdparts && !old_mtdparts && !mtdids && !old_mtdids) ||
 	    (mtdparts && old_mtdparts && mtdids && old_mtdids &&
+	     !mtd_dev_list_updated() && !mtd_del_all_parts_failed &&
 	     !strcmp(mtdparts, old_mtdparts) &&
 	     !strcmp(mtdids, old_mtdids)))
 		return 0;
@@ -174,55 +227,55 @@ int mtd_probe_devices(void)
 	old_mtdparts = strdup(mtdparts);
 	old_mtdids = strdup(mtdids);
 
-	/* If at least one partition is still in use, do not delete anything */
-	mtd_for_each_device(mtd) {
-		if (mtd->usecount) {
-			printf("Partition \"%s\" already in use, aborting\n",
-			       mtd->name);
-			return -EACCES;
-		}
-	}
+	/*
+	 * Remove all old parts. Note that partition removal can fail in case
+	 * one of the partition is still being used by an MTD user, so this
+	 * does not guarantee that all old partitions are gone.
+	 */
+	mtd_del_all_parts();
 
 	/*
-	 * Everything looks clear, remove all partitions. It is not safe to
-	 * remove entries from the mtd_for_each_device loop as it uses idr
-	 * indexes and the partitions removal is done in bulk (all partitions of
-	 * one device at the same time), so break and iterate from start each
-	 * time a new partition is found and deleted.
+	 * Call mtd_dev_list_updated() to clear updates generated by our own
+	 * parts removal loop.
 	 */
-	while (remaining_partitions) {
-		remaining_partitions = false;
-		mtd_for_each_device(mtd) {
-			if (!mtd_is_partition(mtd) && mtd_has_partitions(mtd)) {
-				del_mtd_partitions(mtd);
-				remaining_partitions = true;
-				break;
-			}
-		}
-	}
+	mtd_dev_list_updated();
 
 	/* If either mtdparts or mtdids is empty, then exit */
 	if (!mtdparts || !mtdids)
 		return 0;
 
 	/* Start the parsing by ignoring the extra 'mtdparts=' prefix, if any */
-	if (strstr(mtdparts, "mtdparts="))
+	if (!strncmp(mtdparts, "mtdparts=", sizeof("mtdparts=") - 1))
 		mtdparts += 9;
 
 	/* For each MTD device in mtdparts */
-	while (mtdparts[0] != '\0') {
+	for (; mtdparts[0] != '\0'; mtdparts = mtdparts_next) {
 		char mtd_name[MTD_NAME_MAX_LEN], *colon;
 		struct mtd_partition *parts;
-		int mtd_name_len, nparts;
-		int ret;
+		unsigned int mtd_name_len;
+		int nparts, ret;
+
+		mtdparts_next = strchr(mtdparts, ';');
+		if (!mtdparts_next)
+			mtdparts_next = mtdparts + strlen(mtdparts);
+		else
+			mtdparts_next++;
 
 		colon = strchr(mtdparts, ':');
+		if (colon > mtdparts_next)
+			colon = NULL;
+
 		if (!colon) {
 			printf("Wrong mtdparts: %s\n", mtdparts);
 			return -EINVAL;
 		}
 
-		mtd_name_len = colon - mtdparts;
+		mtd_name_len = (unsigned int)(colon - mtdparts);
+		if (mtd_name_len + 1 > sizeof(mtd_name)) {
+			printf("MTD name too long: %s\n", mtdparts);
+			return -EINVAL;
+		}
+
 		strncpy(mtd_name, mtdparts, mtd_name_len);
 		mtd_name[mtd_name_len] = '\0';
 		/* Move the pointer forward (including the ':') */
@@ -249,15 +302,23 @@ int mtd_probe_devices(void)
 			if (ret || IS_ERR_OR_NULL(mtd)) {
 				printf("Could not find a valid device for %s\n",
 				       mtd_name);
-				mtdparts = strchr(mtdparts, ';');
-				if (mtdparts)
-					mtdparts++;
-
+				mtdparts = mtdparts_next;
 				continue;
 			}
 		}
 
 		/*
+		 * Call mtd_del_parts() again, even if it's already been called
+		 * in mtd_del_all_parts(). We need to know if old partitions are
+		 * still around (because they are still being used by someone),
+		 * and if they are, we shouldn't create new partitions, so just
+		 * skip this MTD device and try the next one.
+		 */
+		ret = mtd_del_parts(mtd, true);
+		if (ret < 0)
+			continue;
+
+		/*
 		 * Parse the MTD device partitions. It will update the mtdparts
 		 * pointer, create an array of parts (that must be freed), and
 		 * return the number of partition structures in the array.
@@ -281,6 +342,12 @@ int mtd_probe_devices(void)
 		put_mtd_device(mtd);
 	}
 
+	/*
+	 * Call mtd_dev_list_updated() to clear updates generated by our own
+	 * parts registration loop.
+	 */
+	mtd_dev_list_updated();
+
 	return 0;
 }
 #else