[U-Boot] [PATCH 1/9] mtd: Add a function to report when the MTD dev list has been updated

[U-Boot] [PATCH 1/9] mtd: Add a function to report when the MTD dev list has been updated

[Boris Brezillon]

We need to parse mtdparts/mtids again everytime a device has been
added/removed from the MTD list, but there's currently no way to know
when such an update has been done.

Add an ->updated field to the idr struct that we set to true every time
a device is added/removed and expose a function returning the value
of this field and resetting it to false.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- None
---
 drivers/mtd/mtdcore.c   | 16 +++++++++++++++-
 include/linux/mtd/mtd.h |  1 +
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index fb6c779abbfe..7a15ded8c883 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -87,14 +87,17 @@ struct idr_layer {
 
 struct idr {
 	struct idr_layer id[MAX_IDR_ID];
+	bool updated;
 };
 
 #define DEFINE_IDR(name)	struct idr name;
 
 void idr_remove(struct idr *idp, int id)
 {
-	if (idp->id[id].used)
+	if (idp->id[id].used) {
 		idp->id[id].used = 0;
+		idp->updated = true;
+	}
 
 	return;
 }
@@ -134,6 +137,7 @@ int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t gfp_mask)
 		if (idl->used == 0) {
 			idl->used = 1;
 			idl->ptr = ptr;
+			idp->updated = true;
 			return i;
 		}
 		i++;
@@ -155,6 +159,16 @@ struct mtd_info *__mtd_next_device(int i)
 }
 EXPORT_SYMBOL_GPL(__mtd_next_device);
 
+bool mtd_dev_list_updated(void)
+{
+	if (mtd_idr.updated) {
+		mtd_idr.updated = false;
+		return true;
+	}
+
+	return false;
+}
+
 #ifndef __UBOOT__
 static LIST_HEAD(mtd_notifiers);
 
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 68e591532492..d20ebd820289 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -581,6 +581,7 @@ int mtd_arg_off_size(int argc, char *const argv[], int *idx, loff_t *off,
 void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
 			  const uint64_t length, uint64_t *len_incl_bad,
 			  int *truncated);
+bool mtd_dev_list_updated(void);
 
 /* drivers/mtd/mtd_uboot.c */
 int mtd_search_alternate_name(const char *mtdname, char *altname,
-- 
2.17.1

[U-Boot] [PATCH 2/9] mtd: Parse mtdparts/mtdids again when the MTD list has been updated

[Boris Brezillon]

Updates to the MTD device list should trigger a new parsing of the
mtdids/mtdparts vars even if those vars haven't changed.

Fixes: 5db66b3aee6f ("cmd: mtd: add 'mtd' command")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- None
---
 drivers/mtd/mtd_uboot.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index 5ca560c96879..6a3e64395de2 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -161,9 +161,13 @@ int mtd_probe_devices(void)
 
 	mtd_probe_uclass_mtd_devs();
 
-	/* Check if mtdparts/mtdids changed since last call, otherwise: exit */
+	/*
+	 * Check if mtdparts/mtdids changed or if the MTD dev list was updated
+	 * since last call, otherwise: exit
+	 */
 	if ((!mtdparts && !old_mtdparts && !mtdids && !old_mtdids) ||
 	    (mtdparts && old_mtdparts && mtdids && old_mtdids &&
+	     !mtd_dev_list_updated() &&
 	     !strcmp(mtdparts, old_mtdparts) &&
 	     !strcmp(mtdids, old_mtdids)))
 		return 0;
@@ -201,6 +205,12 @@ int mtd_probe_devices(void)
 		}
 	}
 
+	/*
+	 * Call mtd_dev_list_updated() to clear updates generated by our own
+	 * parts removal loop.
+	 */
+	mtd_dev_list_updated();
+
 	/* If either mtdparts or mtdids is empty, then exit */
 	if (!mtdparts || !mtdids)
 		return 0;
@@ -281,6 +291,12 @@ 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
-- 
2.17.1

[U-Boot] [PATCH 3/9] mtd: Delete partitions attached to the device when a device is deleted

[Boris Brezillon]

If we don't do that, partitions might still be exposed while the
underlying device is gone.

Fixes: 2a74930da57f ("mtd: mtdpart: implement proper partition handling")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- Fix build failures when CONFIG_MTD_PARTITIONS is not enabled
---
 drivers/mtd/mtdcore.c   |  1 +
 include/linux/mtd/mtd.h | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 7a15ded8c883..46657fe7c949 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -528,6 +528,7 @@ int del_mtd_device(struct mtd_info *mtd)
 	struct mtd_notifier *not;
 #endif
 
+	del_mtd_partitions(mtd);
 	mutex_lock(&mtd_table_mutex);
 
 	if (idr_find(&mtd_idr, mtd->index) != mtd) {
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index d20ebd820289..4d0096d9f1d8 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -562,8 +562,23 @@ unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
 /* drivers/mtd/mtdcore.h */
 int add_mtd_device(struct mtd_info *mtd);
 int del_mtd_device(struct mtd_info *mtd);
+
+#ifdef CONFIG_MTD_PARTITIONS
 int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
 int del_mtd_partitions(struct mtd_info *);
+#else
+static inline int add_mtd_partitions(struct mtd_info *mtd,
+				     const struct mtd_partition *parts,
+				     int nparts)
+{
+	return 0;
+}
+
+static inline int del_mtd_partitions(struct mtd_info *mtd)
+{
+	return 0;
+}
+#endif
 
 struct mtd_info *__mtd_next_device(int i);
 #define mtd_for_each_device(mtd)			\
-- 
2.17.1

[U-Boot] [PATCH 4/9] mtd: sf: Make sure we don't register the same device twice

[Boris Brezillon]

spi_flash_mtd_register() can be called several times and each time it
will register the same mtd_info instance like if it was a new one.
The MTD ID allocation gets crazy when that happens, so let's track the
status of the sf_mtd_info object to avoid that.

Fixes: 9fe6d8716e09 ("mtd, spi: Add MTD layer driver")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2
- None
---
 drivers/mtd/spi/sf_mtd.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi/sf_mtd.c b/drivers/mtd/spi/sf_mtd.c
index 58d7e4439903..aabbc3589435 100644
--- a/drivers/mtd/spi/sf_mtd.c
+++ b/drivers/mtd/spi/sf_mtd.c
@@ -10,6 +10,7 @@
 #include <spi_flash.h>
 
 static struct mtd_info sf_mtd_info;
+static bool sf_mtd_registered;
 static char sf_mtd_name[8];
 
 static int spi_flash_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
@@ -73,6 +74,12 @@ static int spi_flash_mtd_number(void)
 
 int spi_flash_mtd_register(struct spi_flash *flash)
 {
+	int ret;
+
+	if (sf_mtd_registered)
+		del_mtd_device(&sf_mtd_info);
+
+	sf_mtd_registered = false;
 	memset(&sf_mtd_info, 0, sizeof(sf_mtd_info));
 	sprintf(sf_mtd_name, "nor%d", spi_flash_mtd_number());
 
@@ -94,7 +101,11 @@ int spi_flash_mtd_register(struct spi_flash *flash)
 	sf_mtd_info.numeraseregions = 0;
 	sf_mtd_info.erasesize = flash->sector_size;
 
-	return add_mtd_device(&sf_mtd_info);
+	ret = add_mtd_device(&sf_mtd_info);
+	if (!ret)
+		sf_mtd_registered = true;
+
+	return ret;
 }
 
 void spi_flash_mtd_unregister(void)
-- 
2.17.1

[U-Boot] [PATCH 5/9] mtd: Use get_mtdids() instead of env_get("mtdids") in mtd_search_alternate_name()

[Boris Brezillon]

The environment is not guaranteed to contain a valid mtdids variable
when called from mtd_search_alternate_name(). Call get_mtdids() instead
of env_get("mtdids").

Fixes: ff4afa8a981e ("mtd: uboot: search for an equivalent MTD name with the mtdids")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
Changes in v2:
- Add Miquel's R-b
- Move board_mtdparts_default() prototype def to fix a build failure
---
 drivers/mtd/mtd_uboot.c | 49 ++++++++++++++++++++---------------------
 1 file changed, 24 insertions(+), 25 deletions(-)

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index 6a3e64395de2..c4434d70520d 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
 
-- 
2.17.1

[U-Boot] [PATCH 6/9] mtd: Be more strict on the "mtdparts=" prefix check

[Boris Brezillon]

strstr() does not guarantee that the string we're searching for is
placed at the beginning. Use strncmp() instead.

Fixes: 5db66b3aee6f ("cmd: mtd: add 'mtd' command")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- New patch
---
 drivers/mtd/mtd_uboot.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index c4434d70520d..d551aee20203 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -215,7 +215,7 @@ int mtd_probe_devices(void)
 		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 */
-- 
2.17.1

[U-Boot] [PATCH 7/9] mtd: Make sure the name passed in mtdparts fits in mtd_name[]

[Boris Brezillon]

The local mtd_name[] variable is limited in size. Return an error if
the name passed in mtdparts does not fit in this local var.

Fixes: 5db66b3aee6f ("cmd: mtd: add 'mtd' command")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- New patch
---
 drivers/mtd/mtd_uboot.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index d551aee20203..0eda36278309 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -222,8 +222,8 @@ int mtd_probe_devices(void)
 	while (mtdparts[0] != '\0') {
 		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;
 
 		colon = strchr(mtdparts, ':');
 		if (!colon) {
@@ -231,7 +231,12 @@ int mtd_probe_devices(void)
 			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 ':') */
-- 
2.17.1

[U-Boot] [PATCH 8/9] mtd: Make sure we don't parse MTD partitions belonging to another dev

[Boris Brezillon]

The mtdparts variable might contain partition definitions for several
MTD devices. Each partition layout is separated by a ';', so let's
make sure we don't pick a wrong name when mtdparts is malformed.

Fixes: 5db66b3aee6f ("cmd: mtd: add 'mtd' command")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- New patch
---
 drivers/mtd/mtd_uboot.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index 0eda36278309..6a36948b917b 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -155,6 +155,7 @@ int mtd_probe_devices(void)
 	static char *old_mtdids;
 	const char *mtdparts = get_mtdparts();
 	const char *mtdids = get_mtdids();
+	const char *mtdparts_next = mtdparts;
 	bool remaining_partitions = true;
 	struct mtd_info *mtd;
 
@@ -219,13 +220,22 @@ int mtd_probe_devices(void)
 		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;
 		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;
@@ -263,10 +273,7 @@ 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;
 			}
 		}
-- 
2.17.1

[U-Boot] [PATCH 9/9] mtd: Don't stop MTD partition creation when it fails on one device

[Boris Brezillon]

MTD partition creation code is a bit tricky. It tries to figure out
when things have changed (either MTD dev list or mtdparts/mtdids vars)
and when that happens it first deletes all the partitions that had been
previously created and then creates the new ones based on the new
mtdparts/mtdids values.
But before deleting the old partitions, it ensures that none of the
currently registered parts are being used and bails out when that's
not the case. So, we end up in a situation where, if at least one MTD
dev has one of its partitions used by someone (UBI for instance), the
partitions update logic no longer works for other devs.

Rework the code to relax the logic and allow updates of MTD parts on
devices that are not being used (we still refuse to updates parts on
devices who have at least one of their partitions used by someone).

Fixes: 5db66b3aee6f ("cmd: mtd: add 'mtd' command")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2:
- New patch
---
 drivers/mtd/mtd_uboot.c | 87 +++++++++++++++++++++++++++--------------
 drivers/mtd/mtdpart.c   | 12 ++++++
 include/linux/mtd/mtd.h |  2 +
 3 files changed, 72 insertions(+), 29 deletions(-)

diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index 6a36948b917b..c9909d56842e 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -149,6 +149,48 @@ 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 void mtd_del_all_parts(void)
+{
+	struct mtd_info *mtd;
+	int ret = 0;
+
+	/*
+	 * 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;
+		}
+	} while (ret > 0);
+}
+
 int mtd_probe_devices(void)
 {
 	static char *old_mtdparts;
@@ -156,7 +198,6 @@ int mtd_probe_devices(void)
 	const char *mtdparts = get_mtdparts();
 	const char *mtdids = get_mtdids();
 	const char *mtdparts_next = mtdparts;
-	bool remaining_partitions = true;
 	struct mtd_info *mtd;
 
 	mtd_probe_uclass_mtd_devs();
@@ -178,37 +219,14 @@ 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;
-		}
-	}
-
 	/*
-	 * 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.
+	 * 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.
 	 */
-	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_del_all_parts();
 
-	/*
-	 * Call mtd_dev_list_updated() to clear updates generated by our own
-	 * parts removal loop.
-	 */
+	/* Clear the "MTD dev list" updated flag. */
 	mtd_dev_list_updated();
 
 	/* If either mtdparts or mtdids is empty, then exit */
@@ -278,6 +296,17 @@ int mtd_probe_devices(void)
 			}
 		}
 
+		/*
+		 * 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
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 4d2ac8107f01..fd8d8e5ea729 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -63,6 +63,18 @@ char *kstrdup(const char *s, gfp_t gfp)
 #define MTD_SIZE_REMAINING		(~0LLU)
 #define MTD_OFFSET_NOT_SPECIFIED	(~0LLU)
 
+bool mtd_partitions_used(struct mtd_info *master)
+{
+	struct mtd_info *slave;
+
+	list_for_each_entry(slave, &master->partitions, node) {
+		if (slave->usecount)
+			return true;
+	}
+
+	return false;
+}
+
 /**
  * mtd_parse_partition - Parse @mtdparts partition definition, fill @partition
  *                       with it and update the @mtdparts string pointer.
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 4d0096d9f1d8..cd1f557a2f31 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -366,6 +366,8 @@ static inline bool mtd_has_partitions(const struct mtd_info *mtd)
 	return !list_empty(&mtd->partitions);
 }
 
+bool mtd_partitions_used(struct mtd_info *master);
+
 int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
 		      struct mtd_oob_region *oobecc);
 int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
-- 
2.17.1

[U-Boot] [PATCH 1/9] mtd: Add a function to report when the MTD dev list has been updated

[Boris Brezillon]

Crap! I forgot to pass -v2 to git format patch.

On Mon, 19 Nov 2018 12:51:13 +0100
Boris Brezillon <boris.brezillon@bootlin.com> wrote:

> We need to parse mtdparts/mtids again everytime a device has been
> added/removed from the MTD list, but there's currently no way to know
> when such an update has been done.
> 
> Add an ->updated field to the idr struct that we set to true every time
> a device is added/removed and expose a function returning the value
> of this field and resetting it to false.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
> ---
> Changes in v2:
> - None
> ---
>  drivers/mtd/mtdcore.c   | 16 +++++++++++++++-
>  include/linux/mtd/mtd.h |  1 +
>  2 files changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> index fb6c779abbfe..7a15ded8c883 100644
> --- a/drivers/mtd/mtdcore.c
> +++ b/drivers/mtd/mtdcore.c
> @@ -87,14 +87,17 @@ struct idr_layer {
>  
>  struct idr {
>  	struct idr_layer id[MAX_IDR_ID];
> +	bool updated;
>  };
>  
>  #define DEFINE_IDR(name)	struct idr name;
>  
>  void idr_remove(struct idr *idp, int id)
>  {
> -	if (idp->id[id].used)
> +	if (idp->id[id].used) {
>  		idp->id[id].used = 0;
> +		idp->updated = true;
> +	}
>  
>  	return;
>  }
> @@ -134,6 +137,7 @@ int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t gfp_mask)
>  		if (idl->used == 0) {
>  			idl->used = 1;
>  			idl->ptr = ptr;
> +			idp->updated = true;
>  			return i;
>  		}
>  		i++;
> @@ -155,6 +159,16 @@ struct mtd_info *__mtd_next_device(int i)
>  }
>  EXPORT_SYMBOL_GPL(__mtd_next_device);
>  
> +bool mtd_dev_list_updated(void)
> +{
> +	if (mtd_idr.updated) {
> +		mtd_idr.updated = false;
> +		return true;
> +	}
> +
> +	return false;
> +}
> +
>  #ifndef __UBOOT__
>  static LIST_HEAD(mtd_notifiers);
>  
> diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
> index 68e591532492..d20ebd820289 100644
> --- a/include/linux/mtd/mtd.h
> +++ b/include/linux/mtd/mtd.h
> @@ -581,6 +581,7 @@ int mtd_arg_off_size(int argc, char *const argv[], int *idx, loff_t *off,
>  void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
>  			  const uint64_t length, uint64_t *len_incl_bad,
>  			  int *truncated);
> +bool mtd_dev_list_updated(void);
>  
>  /* drivers/mtd/mtd_uboot.c */
>  int mtd_search_alternate_name(const char *mtdname, char *altname,

[U-Boot] [PATCH 1/9] mtd: Add a function to report when the MTD dev list has been updated

[Heiko Schocher]

Hello Boris,

Am 19.11.2018 um 13:40 schrieb Boris Brezillon:
> Crap! I forgot to pass -v2 to git format patch.

:-P

Do you use u-boot:/tools/patman ?

bye,
Heiko
> 
> On Mon, 19 Nov 2018 12:51:13 +0100
> Boris Brezillon <boris.brezillon@bootlin.com> wrote:
> 
>> We need to parse mtdparts/mtids again everytime a device has been
>> added/removed from the MTD list, but there's currently no way to know
>> when such an update has been done.
>>
>> Add an ->updated field to the idr struct that we set to true every time
>> a device is added/removed and expose a function returning the value
>> of this field and resetting it to false.
>>
>> Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
>> ---
>> Changes in v2:
>> - None
>> ---
>>   drivers/mtd/mtdcore.c   | 16 +++++++++++++++-
>>   include/linux/mtd/mtd.h |  1 +
>>   2 files changed, 16 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
>> index fb6c779abbfe..7a15ded8c883 100644
>> --- a/drivers/mtd/mtdcore.c
>> +++ b/drivers/mtd/mtdcore.c
>> @@ -87,14 +87,17 @@ struct idr_layer {
>>   
>>   struct idr {
>>   	struct idr_layer id[MAX_IDR_ID];
>> +	bool updated;
>>   };
>>   
>>   #define DEFINE_IDR(name)	struct idr name;
>>   
>>   void idr_remove(struct idr *idp, int id)
>>   {
>> -	if (idp->id[id].used)
>> +	if (idp->id[id].used) {
>>   		idp->id[id].used = 0;
>> +		idp->updated = true;
>> +	}
>>   
>>   	return;
>>   }
>> @@ -134,6 +137,7 @@ int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t gfp_mask)
>>   		if (idl->used == 0) {
>>   			idl->used = 1;
>>   			idl->ptr = ptr;
>> +			idp->updated = true;
>>   			return i;
>>   		}
>>   		i++;
>> @@ -155,6 +159,16 @@ struct mtd_info *__mtd_next_device(int i)
>>   }
>>   EXPORT_SYMBOL_GPL(__mtd_next_device);
>>   
>> +bool mtd_dev_list_updated(void)
>> +{
>> +	if (mtd_idr.updated) {
>> +		mtd_idr.updated = false;
>> +		return true;
>> +	}
>> +
>> +	return false;
>> +}
>> +
>>   #ifndef __UBOOT__
>>   static LIST_HEAD(mtd_notifiers);
>>   
>> diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
>> index 68e591532492..d20ebd820289 100644
>> --- a/include/linux/mtd/mtd.h
>> +++ b/include/linux/mtd/mtd.h
>> @@ -581,6 +581,7 @@ int mtd_arg_off_size(int argc, char *const argv[], int *idx, loff_t *off,
>>   void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
>>   			  const uint64_t length, uint64_t *len_incl_bad,
>>   			  int *truncated);
>> +bool mtd_dev_list_updated(void);
>>   
>>   /* drivers/mtd/mtd_uboot.c */
>>   int mtd_search_alternate_name(const char *mtdname, char *altname,
> 

-- 
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HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-52   Fax: +49-8142-66989-80   Email: hs at denx.de

[U-Boot] [PATCH 1/9] mtd: Add a function to report when the MTD dev list has been updated

[Boris Brezillon]

On Mon, 19 Nov 2018 14:30:28 +0100
Heiko Schocher <hs@denx.de> wrote:

> Hello Boris,
> 
> Am 19.11.2018 um 13:40 schrieb Boris Brezillon:
> > Crap! I forgot to pass -v2 to git format patch.  
> 
> :-P
> 
> Do you use u-boot:/tools/patman ?

Nope, I don't, but I guess I should :-).