1 files changed, 143 insertions, 48 deletions

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 8b91a55ec0d2..ef6a22f372f9 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -27,6 +27,7 @@
 #include <linux/log2.h>
 #include <linux/kthread.h>
 #include <linux/kernel.h>
+#include <linux/of.h>
 #include <linux/slab.h>
 #include <linux/major.h>
 #include "ubi.h"
@@ -35,7 +36,7 @@
 #define MTD_PARAM_LEN_MAX 64
 
 /* Maximum number of comma-separated items in the 'mtd=' parameter */
-#define MTD_PARAM_MAX_COUNT 5
+#define MTD_PARAM_MAX_COUNT 6
 
 /* Maximum value for the number of bad PEBs per 1024 PEBs */
 #define MAX_MTD_UBI_BEB_LIMIT 768
@@ -54,6 +55,7 @@
  * @vid_hdr_offs: VID header offset
  * @max_beb_per1024: maximum expected number of bad PEBs per 1024 PEBs
  * @enable_fm: enable fastmap when value is non-zero
+ * @need_resv_pool: reserve pool->max_size pebs when value is none-zero
  */
 struct mtd_dev_param {
 	char name[MTD_PARAM_LEN_MAX];
@@ -61,6 +63,7 @@ struct mtd_dev_param {
 	int vid_hdr_offs;
 	int max_beb_per1024;
 	int enable_fm;
+	int need_resv_pool;
 };
 
 /* Numbers of elements set in the @mtd_dev_param array */
@@ -90,7 +93,7 @@ static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
 /* Serializes UBI devices creations and removals */
 DEFINE_MUTEX(ubi_devices_mutex);
 
-/* Protects @ubi_devices and @ubi->ref_count */
+/* Protects @ubi_devices, @ubi->ref_count and @ubi->is_dead */
 static DEFINE_SPINLOCK(ubi_devices_lock);
 
 /* "Show" method for files in '/<sysfs>/class/ubi/' */
@@ -109,7 +112,7 @@ static struct attribute *ubi_class_attrs[] = {
 ATTRIBUTE_GROUPS(ubi_class);
 
 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
-struct class ubi_class = {
+const struct class ubi_class = {
 	.name		= UBI_NAME_STR,
 	.class_groups	= ubi_class_groups,
 };
@@ -258,6 +261,9 @@ struct ubi_device *ubi_get_device(int ubi_num)
 
 	spin_lock(&ubi_devices_lock);
 	ubi = ubi_devices[ubi_num];
+	if (ubi && ubi->is_dead)
+		ubi = NULL;
+
 	if (ubi) {
 		ubi_assert(ubi->ref_count >= 0);
 		ubi->ref_count += 1;
@@ -295,7 +301,7 @@ struct ubi_device *ubi_get_by_major(int major)
 	spin_lock(&ubi_devices_lock);
 	for (i = 0; i < UBI_MAX_DEVICES; i++) {
 		ubi = ubi_devices[i];
-		if (ubi && MAJOR(ubi->cdev.dev) == major) {
+		if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) {
 			ubi_assert(ubi->ref_count >= 0);
 			ubi->ref_count += 1;
 			get_device(&ubi->dev);
@@ -324,7 +330,7 @@ int ubi_major2num(int major)
 	for (i = 0; i < UBI_MAX_DEVICES; i++) {
 		struct ubi_device *ubi = ubi_devices[i];
 
-		if (ubi && MAJOR(ubi->cdev.dev) == major) {
+		if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) {
 			ubi_num = ubi->ubi_num;
 			break;
 		}
@@ -511,7 +517,7 @@ static void ubi_free_volumes_from(struct ubi_device *ubi, int from)
 	int i;
 
 	for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
-		if (!ubi->volumes[i])
+		if (!ubi->volumes[i] || ubi->volumes[i]->is_dead)
 			continue;
 		ubi_eba_replace_table(ubi->volumes[i], NULL);
 		ubi_fastmap_destroy_checkmap(ubi->volumes[i]);
@@ -825,6 +831,7 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
  * @vid_hdr_offset: VID header offset
  * @max_beb_per1024: maximum expected number of bad PEB per 1024 PEBs
  * @disable_fm: whether disable fastmap
+ * @need_resv_pool: whether reserve pebs to fill fm_pool
  *
  * This function attaches MTD device @mtd_dev to UBI and assign @ubi_num number
  * to the newly created UBI device, unless @ubi_num is %UBI_DEV_NUM_AUTO, in
@@ -840,7 +847,8 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
  * @ubi_devices_mutex.
  */
 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
-		       int vid_hdr_offset, int max_beb_per1024, bool disable_fm)
+		       int vid_hdr_offset, int max_beb_per1024, bool disable_fm,
+		       bool need_resv_pool)
 {
 	struct ubi_device *ubi;
 	int i, err;
@@ -894,6 +902,13 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 		return -EINVAL;
 	}
 
+	/* UBI cannot work on flashes with zero erasesize. */
+	if (!mtd->erasesize) {
+		pr_err("ubi: refuse attaching mtd%d - zero erasesize flash is not supported\n",
+			mtd->index);
+		return -EINVAL;
+	}
+
 	if (ubi_num == UBI_DEV_NUM_AUTO) {
 		/* Search for an empty slot in the @ubi_devices array */
 		for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
@@ -944,6 +959,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 		UBI_FM_MIN_POOL_SIZE);
 
 	ubi->fm_wl_pool.max_size = ubi->fm_pool.max_size / 2;
+	ubi->fm_pool_rsv_cnt = need_resv_pool ? ubi->fm_pool.max_size : 0;
 	ubi->fm_disabled = (!fm_autoconvert || disable_fm) ? 1 : 0;
 	if (fm_debug)
 		ubi_enable_dbg_chk_fastmap(ubi);
@@ -1086,7 +1102,6 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
 		return -EINVAL;
 
 	spin_lock(&ubi_devices_lock);
-	put_device(&ubi->dev);
 	ubi->ref_count -= 1;
 	if (ubi->ref_count) {
 		if (!anyway) {
@@ -1097,6 +1112,13 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
 		ubi_err(ubi, "%s reference count %d, destroy anyway",
 			ubi->ubi_name, ubi->ref_count);
 	}
+	ubi->is_dead = true;
+	spin_unlock(&ubi_devices_lock);
+
+	ubi_notify_all(ubi, UBI_VOLUME_SHUTDOWN, NULL);
+
+	spin_lock(&ubi_devices_lock);
+	put_device(&ubi->dev);
 	ubi_devices[ubi_num] = NULL;
 	spin_unlock(&ubi_devices_lock);
 
@@ -1207,43 +1229,43 @@ static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
 	return mtd;
 }
 
-static int __init ubi_init(void)
+static void ubi_notify_add(struct mtd_info *mtd)
 {
-	int err, i, k;
+	struct device_node *np = mtd_get_of_node(mtd);
+	int err;
 
-	/* Ensure that EC and VID headers have correct size */
-	BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
-	BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
+	if (!of_device_is_compatible(np, "linux,ubi"))
+		return;
 
-	if (mtd_devs > UBI_MAX_DEVICES) {
-		pr_err("UBI error: too many MTD devices, maximum is %d\n",
-		       UBI_MAX_DEVICES);
-		return -EINVAL;
-	}
+	/*
+	 * we are already holding &mtd_table_mutex, but still need
+	 * to bump refcount
+	 */
+	err = __get_mtd_device(mtd);
+	if (err)
+		return;
 
-	/* Create base sysfs directory and sysfs files */
-	err = class_register(&ubi_class);
+	/* called while holding mtd_table_mutex */
+	mutex_lock_nested(&ubi_devices_mutex, SINGLE_DEPTH_NESTING);
+	err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0, false, false);
+	mutex_unlock(&ubi_devices_mutex);
 	if (err < 0)
-		return err;
-
-	err = misc_register(&ubi_ctrl_cdev);
-	if (err) {
-		pr_err("UBI error: cannot register device\n");
-		goto out;
-	}
+		__put_mtd_device(mtd);
+}
 
-	ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
-					      sizeof(struct ubi_wl_entry),
-					      0, 0, NULL);
-	if (!ubi_wl_entry_slab) {
-		err = -ENOMEM;
-		goto out_dev_unreg;
-	}
+static void ubi_notify_remove(struct mtd_info *mtd)
+{
+	/* do nothing for now */
+}
 
-	err = ubi_debugfs_init();
-	if (err)
-		goto out_slab;
+static struct mtd_notifier ubi_mtd_notifier = {
+	.add = ubi_notify_add,
+	.remove = ubi_notify_remove,
+};
 
+static int __init ubi_init_attach(void)
+{
+	int err, i, k;
 
 	/* Attach MTD devices */
 	for (i = 0; i < mtd_devs; i++) {
@@ -1266,7 +1288,8 @@ static int __init ubi_init(void)
 		mutex_lock(&ubi_devices_mutex);
 		err = ubi_attach_mtd_dev(mtd, p->ubi_num,
 					 p->vid_hdr_offs, p->max_beb_per1024,
-					 p->enable_fm == 0);
+					 p->enable_fm == 0,
+					 p->need_resv_pool != 0);
 		mutex_unlock(&ubi_devices_mutex);
 		if (err < 0) {
 			pr_err("UBI error: cannot attach mtd%d\n",
@@ -1291,24 +1314,81 @@ static int __init ubi_init(void)
 		}
 	}
 
+	return 0;
+
+out_detach:
+	for (k = 0; k < i; k++)
+		if (ubi_devices[k]) {
+			mutex_lock(&ubi_devices_mutex);
+			ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
+			mutex_unlock(&ubi_devices_mutex);
+		}
+	return err;
+}
+#ifndef CONFIG_MTD_UBI_MODULE
+late_initcall(ubi_init_attach);
+#endif
+
+static int __init ubi_init(void)
+{
+	int err;
+
+	/* Ensure that EC and VID headers have correct size */
+	BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
+	BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
+
+	if (mtd_devs > UBI_MAX_DEVICES) {
+		pr_err("UBI error: too many MTD devices, maximum is %d\n",
+		       UBI_MAX_DEVICES);
+		return -EINVAL;
+	}
+
+	/* Create base sysfs directory and sysfs files */
+	err = class_register(&ubi_class);
+	if (err < 0)
+		return err;
+
+	err = misc_register(&ubi_ctrl_cdev);
+	if (err) {
+		pr_err("UBI error: cannot register device\n");
+		goto out;
+	}
+
+	ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
+					      sizeof(struct ubi_wl_entry),
+					      0, 0, NULL);
+	if (!ubi_wl_entry_slab) {
+		err = -ENOMEM;
+		goto out_dev_unreg;
+	}
+
+	err = ubi_debugfs_init();
+	if (err)
+		goto out_slab;
+
 	err = ubiblock_init();
 	if (err) {
 		pr_err("UBI error: block: cannot initialize, error %d\n", err);
 
 		/* See comment above re-ubi_is_module(). */
 		if (ubi_is_module())
-			goto out_detach;
+			goto out_debugfs;
+	}
+
+	register_mtd_user(&ubi_mtd_notifier);
+
+	if (ubi_is_module()) {
+		err = ubi_init_attach();
+		if (err)
+			goto out_mtd_notifier;
 	}
 
 	return 0;
 
-out_detach:
-	for (k = 0; k < i; k++)
-		if (ubi_devices[k]) {
-			mutex_lock(&ubi_devices_mutex);
-			ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
-			mutex_unlock(&ubi_devices_mutex);
-		}
+out_mtd_notifier:
+	unregister_mtd_user(&ubi_mtd_notifier);
+	ubiblock_exit();
+out_debugfs:
 	ubi_debugfs_exit();
 out_slab:
 	kmem_cache_destroy(ubi_wl_entry_slab);
@@ -1319,13 +1399,15 @@ out:
 	pr_err("UBI error: cannot initialize UBI, error %d\n", err);
 	return err;
 }
-late_initcall(ubi_init);
+device_initcall(ubi_init);
+
 
 static void __exit ubi_exit(void)
 {
 	int i;
 
 	ubiblock_exit();
+	unregister_mtd_user(&ubi_mtd_notifier);
 
 	for (i = 0; i < UBI_MAX_DEVICES; i++)
 		if (ubi_devices[i]) {
@@ -1455,7 +1537,7 @@ static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
 	if (token) {
 		int err = kstrtoint(token, 10, &p->ubi_num);
 
-		if (err) {
+		if (err || p->ubi_num < UBI_DEV_NUM_AUTO) {
 			pr_err("UBI error: bad value for ubi_num parameter: %s\n",
 			       token);
 			return -EINVAL;
@@ -1475,6 +1557,18 @@ static int ubi_mtd_param_parse(const char *val, const struct kernel_param *kp)
 	} else
 		p->enable_fm = 0;
 
+	token = tokens[5];
+	if (token) {
+		int err = kstrtoint(token, 10, &p->need_resv_pool);
+
+		if (err) {
+			pr_err("UBI error: bad value for need_resv_pool parameter: %s\n",
+				token);
+			return -EINVAL;
+		}
+	} else
+		p->need_resv_pool = 0;
+
 	mtd_devs += 1;
 	return 0;
 }
@@ -1488,6 +1582,7 @@ MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|pa
 		      __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
 		      "Optional \"ubi_num\" parameter specifies UBI device number which have to be assigned to the newly created UBI device (assigned automatically by default)\n"
 		      "Optional \"enable_fm\" parameter determines whether to enable fastmap during attach. If the value is non-zero, fastmap is enabled. Default value is 0.\n"
+		      "Optional \"need_resv_pool\" parameter determines whether to reserve pool->max_size pebs during attach. If the value is non-zero, peb reservation is enabled. Default value is 0.\n"
 		      "\n"
 		      "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
 		      "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n"