From: Thomas Weißschuh <thomas@t-8ch.de>
Date: Wed, 11 Jan 2023 18:13:50 +0000 (+0000)
Subject: lib/sysfs: add function blkdev_is_removable
X-Git-Tag: v2.39-rc1~121
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=216d8b054f7b4ccc80afbba4b7e4f96ccda11379;p=thirdparty%2Futil-linux.git

lib/sysfs: add function blkdev_is_removable

This exactly represents the kernels notion of a "removable" blockdevice.
That is, the device itself is persistent but can contain some sort of
medium that can be changed at runtime.
Specifically it is *not* hotpluggable.
---

diff --git a/include/sysfs.h b/include/sysfs.h
index ad6b609f2a..8d77f75798 100644
--- a/include/sysfs.h
+++ b/include/sysfs.h
@@ -87,6 +87,7 @@ char *sysfs_blkdev_get_devchain(struct path_cxt *pc, char *buf, size_t bufsz);
 int sysfs_blkdev_next_subsystem(struct path_cxt *pc __attribute__((unused)), char *devchain, char **subsys);
 
 int sysfs_blkdev_is_hotpluggable(struct path_cxt *pc);
+int sysfs_blkdev_is_removable(struct path_cxt *pc);
 int sysfs_blkdev_get_wholedisk( struct path_cxt *pc,
                                 char *diskname,
                                 size_t len,
diff --git a/lib/sysfs.c b/lib/sysfs.c
index 92a7e290b0..f325359560 100644
--- a/lib/sysfs.c
+++ b/lib/sysfs.c
@@ -465,7 +465,7 @@ int sysfs_blkdev_is_hotpluggable(struct path_cxt *pc)
 	int rc = 0;
 
 
-	/* check /sys/dev/block/<maj>:<min>/removable attribute */
+	/* check /sys/devices/.../removable attribute */
 	if (ul_path_read_s32(pc, &rc, "removable") == 0 && rc == 1)
 		return 1;
 
@@ -483,6 +483,17 @@ int sysfs_blkdev_is_hotpluggable(struct path_cxt *pc)
 	return rc;
 }
 
+int sysfs_blkdev_is_removable(struct path_cxt *pc)
+{
+	int rc = 0;
+
+	/* check /sys/dev/block/<maj>:<min>/removable attribute */
+	if (ul_path_read_s32(pc, &rc, "removable") == 0)
+		return rc;
+
+	return 0;
+}
+
 static int get_dm_wholedisk(struct path_cxt *pc, char *diskname,
                 size_t len, dev_t *diskdevno)
 {
@@ -1182,6 +1193,7 @@ int main(int argc, char *argv[])
 	}
 
 	printf(" HOTPLUG: %s\n", sysfs_blkdev_is_hotpluggable(pc) ? "yes" : "no");
+	printf(" REMOVABLE: %s\n", sysfs_blkdev_is_removable(pc) ? "yes" : "no");
 	printf(" SLAVES: %d\n", ul_path_count_dirents(pc, "slaves"));
 
 	if (!is_part) {