From 7a80b660c2dbf8f0c3e5cd347f970d4a24a00326 Mon Sep 17 00:00:00 2001
From: Jacob Malevich <jam@daterainc.com>
Date: Fri, 21 Nov 2014 14:42:07 -0800
Subject: [PATCH] bcacheadm unregister devices

uses unregister ioctl to unregister a cacheset that the device
belongs to

Change-Id: I01772de3471888c4951f050b3e92f41b58c5d103
Signed-off-by: Jacob Malevich <jam@daterainc.com>
---
 bcache.c    | 27 +++++++++++++++++++++++----
 bcache.h    |  5 ++++-
 bcacheadm.c | 15 +++++++++++++++
 3 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/bcache.c b/bcache.c
index 1e3668a1..82232c80 100644
--- a/bcache.c
+++ b/bcache.c
@@ -1070,15 +1070,21 @@ int list_cachesets(char *cset_dir, bool list_devs)
 	return 0;
 }
 
-int register_bcache(char *devs)
+static int get_bcache_fd()
 {
-	int ret, bcachefd;
-
-	bcachefd = open("/dev/bcache", O_RDWR);
+	int bcachefd = open("/dev/bcache", O_RDWR);
 	if (bcachefd < 0) {
 		perror("Can't open bcache device\n");
 		exit(EXIT_FAILURE);
 	}
+	return bcachefd;
+}
+
+int register_bcache(char *const *devs)
+{
+	int ret, bcachefd;
+
+	bcachefd = get_bcache_fd();
 
 	ret = ioctl(bcachefd, BCH_IOCTL_REGISTER, devs);
 	if (ret < 0) {
@@ -1086,7 +1092,20 @@ int register_bcache(char *devs)
 		exit(EXIT_FAILURE);
 	}
 	return 0;
+}
 
+int unregister_bcache(char *const *devs)
+{
+	int ret, bcachefd;
+
+	bcachefd = get_bcache_fd();
+
+	ret = ioctl(bcachefd, BCH_IOCTL_UNREGISTER, devs);
+	if (ret < 0) {
+		fprintf(stderr, "ioctl unregister error: %s\n", strerror(ret));
+		exit(EXIT_FAILURE);
+	}
+	return 0;
 }
 
 int probe(char *dev, int udev)
diff --git a/bcache.h b/bcache.h
index efd7525e..41bf13dd 100644
--- a/bcache.h
+++ b/bcache.h
@@ -60,11 +60,14 @@ void show_super_cache(struct cache_sb *, bool);
 struct cache_sb *query_dev(char *, bool, bool, bool, char *dev_uuid);
 int list_cachesets(char *, bool);
 char *parse_array_to_list(char *const *);
-int register_bcache();
+int register_bcache(char *const *);
+int unregister_bcache(char *const *);
 int probe(char *, int);
 void sb_state(struct cache_sb *, char *);
 void read_stat_dir(DIR *, char *, char *, bool);
 void find_matching_uuid(char *, char *, const char*);
+//int add_device(char *);
+//int remove_device(char *);
 
 #define csum_set(i, type)						\
 ({									\
diff --git a/bcacheadm.c b/bcacheadm.c
index e1d92509..913e4ca0 100644
--- a/bcacheadm.c
+++ b/bcacheadm.c
@@ -199,6 +199,10 @@ static NihOption bcache_register_options[] = {
 	NIH_OPTION_LAST
 };
 
+static NihOption bcache_unregister_options[] = {
+	NIH_OPTION_LAST
+};
+
 static NihOption query_devs_options[] = {
 	{'f', "force_csum", N_("force_csum"), NULL, NULL, &force_csum, NULL},
 	{'u', "uuid-only", N_("only print out the uuid for the devices, not the whole superblock"), NULL, NULL, &uuid_only, NULL},
@@ -356,6 +360,13 @@ int bcache_register (NihCommand *command, char *const *args)
 	return ret;
 }
 
+int bcache_unregister (NihCommand *command, char *const *args)
+{
+	int ret = unregister_bcache(args);
+
+	return ret;
+}
+
 int bcache_list_cachesets (NihCommand *command, char *const *args)
 {
 	return list_cachesets(cset_dir, list_devs);
@@ -470,6 +481,10 @@ static NihCommand commands[] = {
 		     "Registers a list of devices",
 		     N_("Registers a list of devices"),
 		     NULL, bcache_register_options, bcache_register},
+	{"unregister", N_("unregister <list of devices>"),
+		     "Unregisters a list of devices",
+		     N_("Unregisters a list of devices"),
+		     NULL, bcache_unregister_options, bcache_unregister},
 	{"list-cachesets", N_("list-cachesets"),
 			   "Lists cachesets in /sys/fs/bcache",
 			   N_("Lists cachesets in /sys/fs/bcache"),