diff --git a/cmds-device.c b/cmds-device.c index d3102ba7..59074438 100644 --- a/cmds-device.c +++ b/cmds-device.c @@ -254,10 +254,32 @@ static int cmd_device_delete(int argc, char **argv) return _cmd_device_remove(argc, argv, cmd_device_delete_usage); } +static int btrfs_forget_devices(char *path) +{ + struct btrfs_ioctl_vol_args args; + int ret; + int fd; + + fd = open("/dev/btrfs-control", O_RDWR); + if (fd < 0) + return -errno; + + memset(&args, 0, sizeof(args)); + if (path) + strncpy_null(args.name, path); + ret = ioctl(fd, BTRFS_IOC_FORGET_DEV, &args); + if (ret) + ret = -errno; + close(fd); + return ret; +} + static const char * const cmd_device_scan_usage[] = { - "btrfs device scan [(-d|--all-devices)| [...]]", - "Scan devices for a btrfs filesystem", + "btrfs device scan [(-d|--all-devices)|(-u|--forget)| "\ + "[...]]", + "Scan or forget (deregister) devices for a btrfs filesystem", " -d|--all-devices (deprecated)", + " -u|--forget [ ..]", NULL }; @@ -267,37 +289,53 @@ static int cmd_device_scan(int argc, char **argv) int devstart; int all = 0; int ret = 0; + int forget = 0; optind = 0; while (1) { int c; static const struct option long_options[] = { { "all-devices", no_argument, NULL, 'd'}, + { "forget", no_argument, NULL, 'u'}, { NULL, 0, NULL, 0} }; - c = getopt_long(argc, argv, "d", long_options, NULL); + c = getopt_long(argc, argv, "du", long_options, NULL); if (c < 0) break; switch (c) { case 'd': all = 1; break; + case 'u': + forget = 1; + break; default: usage(cmd_device_scan_usage); } } devstart = optind; + if (all && forget) + usage(cmd_device_scan_usage); + if (all && check_argc_max(argc - optind, 1)) usage(cmd_device_scan_usage); if (all || argc - optind == 0) { - printf("Scanning for Btrfs filesystems\n"); - ret = btrfs_scan_devices(); - error_on(ret, "error %d while scanning", ret); - ret = btrfs_register_all_devices(); - error_on(ret, "there are %d errors while registering devices", ret); + if (forget) { + ret = btrfs_forget_devices(NULL); + error_on(ret, "'%s', forget failed", + strerror(-ret)); + } else { + printf("Scanning for Btrfs filesystems\n"); + ret = btrfs_scan_devices(); + error_on(ret, "error %d while scanning", ret); + ret = btrfs_register_all_devices(); + error_on(ret, + "there are %d errors while registering devices", + ret); + } goto out; } @@ -315,11 +353,19 @@ static int cmd_device_scan(int argc, char **argv) ret = 1; goto out; } - printf("Scanning for Btrfs filesystems in '%s'\n", path); - if (btrfs_register_one_device(path) != 0) { - ret = 1; - free(path); - goto out; + if (forget) { + ret = btrfs_forget_devices(path); + if (ret) + error("Can't forget '%s': %s", + path, strerror(-ret)); + } else { + printf("Scanning for Btrfs filesystems in '%s'\n", + path); + if (btrfs_register_one_device(path) != 0) { + ret = 1; + free(path); + goto out; + } } free(path); } diff --git a/ioctl.h b/ioctl.h index 4bf91ddb..66ee599f 100644 --- a/ioctl.h +++ b/ioctl.h @@ -814,6 +814,8 @@ 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_FORGET_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