From: San Mehat <san@google.com>
Date: Sat, 10 Oct 2009 16:35:24 +0000 (-0700)
Subject: block: genhd: Add disk/partition specific uevent callbacks for partition info
X-Git-Tag: firefly_0821_release~3593
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4258bc23b8760f975b6b755a0862dfb0047ad55b;p=firefly-linux-kernel-4.4.55.git

block: genhd: Add disk/partition specific uevent callbacks for partition info

For disk devices, a new uevent parameter 'NPARTS' specifies the number
of partitions detected by the kernel. Partition devices get 'PARTN' which
specifies the partitions index in the table, and 'PARTNAME', which
specifies PARTNAME specifices the partition name of a partition device

Signed-off-by: Dima Zavin <dima@android.com>
(cherry picked from commit 9b9ae694cce47e568fd8f7619c70f1fc91e5b81d)

Change-Id: I5cb7496c9dcd7659116f1b4d5577ac85be102fb5
---

diff --git a/block/genhd.c b/block/genhd.c
index e5cafa51567c..817c67c9e45e 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1117,6 +1117,22 @@ static void disk_release(struct device *dev)
 		blk_put_queue(disk->queue);
 	kfree(disk);
 }
+
+static int disk_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct gendisk *disk = dev_to_disk(dev);
+	struct disk_part_iter piter;
+	struct hd_struct *part;
+	int cnt = 0;
+
+	disk_part_iter_init(&piter, disk, 0);
+	while((part = disk_part_iter_next(&piter)))
+		cnt++;
+	disk_part_iter_exit(&piter);
+	add_uevent_var(env, "NPARTS=%u", cnt);
+	return 0;
+}
+
 struct class block_class = {
 	.name		= "block",
 };
@@ -1136,6 +1152,7 @@ static struct device_type disk_type = {
 	.groups		= disk_attr_groups,
 	.release	= disk_release,
 	.devnode	= block_devnode,
+	.uevent		= disk_uevent,
 };
 
 #ifdef CONFIG_PROC_FS
diff --git a/block/partition-generic.c b/block/partition-generic.c
index 3b030157ec85..d12489ea7209 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -216,10 +216,21 @@ static void part_release(struct device *dev)
 	kfree(p);
 }
 
+static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct hd_struct *part = dev_to_part(dev);
+
+	add_uevent_var(env, "PARTN=%u", part->partno);
+	if (part->info && part->info->volname[0])
+		add_uevent_var(env, "PARTNAME=%s", part->info->volname);
+	return 0;
+}
+
 struct device_type part_type = {
 	.name		= "partition",
 	.groups		= part_attr_groups,
 	.release	= part_release,
+	.uevent		= part_uevent,
 };
 
 static void delete_partition_rcu_cb(struct rcu_head *head)