This patch adds
btrfs device ignode <dev>
so that a device can be ignored/missed during mount if the device is
already been scanned. Basically, this command will undo the effect
of the command
btrfs device scan <dev>
This change is compatible with older kernel without the ioctl
BTRFS_IOC_IGNORE_DEV which is added here. At which it shall
report 'Inappropriate ioctl for device'. And will report
'Operation not permitted' on mounted device.
Signed-off-by: Anand Jain <anand.j...@oracle.com>
---
cmds-device.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
ioctl.h | 2 ++
2 files changed, 56 insertions(+)
diff --git a/cmds-device.c b/cmds-device.c
index 4337eb272037..78280e099492 100644
--- a/cmds-device.c
+++ b/cmds-device.c
@@ -320,6 +320,59 @@ out:
return !!ret;
}
+static const char * const cmd_device_ignore_usage[] = {
+ "btrfs device ignore [<device>]",
+ "Ignore a device in the btrfs kernel module.",
+ NULL
+};
+
+static int btrfs_ignore_one_device(char *path)
+{
+ struct btrfs_ioctl_vol_args args;
+ int fd;
+ int ret;
+
+ fd = open("/dev/btrfs-control", O_RDWR);
+ if (fd < 0)
+ return -errno;
+
+ memset(&args, 0, sizeof(args));
+ strncpy_null(args.name, path);
+ ret = ioctl(fd, BTRFS_IOC_IGNORE_DEV, &args);
+ if (ret)
+ ret = -errno;
+ close(fd);
+ return ret;
+}
+
+static int cmd_device_ignore(int argc, char **argv)
+{
+ int ret = 0;
+ char *path;
+
+ if (check_argc_max(argc - optind, 1))
+ usage(cmd_device_ignore_usage);
+
+ if (is_block_device(argv[1]) != 1) {
+ error("Not a block device: %s", argv[1]);
+ return -ENOENT;
+ }
+
+ path = canonicalize_path(argv[1]);
+ if (!path) {
+ error("Could not canonicalize path '%s': %s",
+ argv[1], strerror(errno));
+ return -ENOENT;
+ }
+
+ ret = btrfs_ignore_one_device(path);
+ if (ret)
+ error("Can't ignore %s: %s", path, strerror(-ret));
+
+ free(path);
+ return ret;
+}
+
static const char * const cmd_device_ready_usage[] = {
"btrfs device ready <device>",
"Check device to see if it has all of its devices in cache for
mounting",
@@ -595,6 +648,7 @@ const struct cmd_group device_cmd_group = {
CMD_ALIAS },
{ "remove", cmd_device_remove, cmd_device_remove_usage, NULL, 0
},
{ "scan", cmd_device_scan, cmd_device_scan_usage, NULL, 0 },
+ { "ignore", cmd_device_ignore, cmd_device_ignore_usage, NULL, 0
},
{ "ready", cmd_device_ready, cmd_device_ready_usage, NULL, 0 },
{ "stats", cmd_device_stats, cmd_device_stats_usage, NULL, 0 },
{ "usage", cmd_device_usage,
diff --git a/ioctl.h b/ioctl.h
index 709e996f401c..bef8508119aa 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -721,6 +721,8 @@ static inline char *btrfs_err_str(enum btrfs_err_code
err_code)
struct btrfs_ioctl_vol_args)
#define BTRFS_IOC_SCAN_DEV _IOW(BTRFS_IOCTL_MAGIC, 4, \
struct btrfs_ioctl_vol_args)
+#define BTRFS_IOC_IGNORE_DEV _IOW(BTRFS_IOCTL_MAGIC, 5, \
+ struct btrfs_ioctl_vol_args)
/* trans start and trans end are dangerous, and only for
* use by applications that know how to avoid the
* resulting deadlocks
--
2.13.1
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