Jeff Mahoney
2013-Sep-10 04:33 UTC
[PATCH 2/2 v2] utils: add support for getting/changing file system, features
This patch adds support for getting and changing file system
feature bits. It supports both unmounted and mounted operation via
a new set of ioctls.
Changing bits not supported by the tools directly can be forced with -f
when the file system is unmounted.
v2: Implemented new ioctl methods from newer ioctl patchset; Cleanup
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
cmds-filesystem.c | 43 ++++
ioctl.h | 12 ++
man/btrfs.8.in | 28 +++
utils.c | 588 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
utils.h | 9 +
5 files changed, 680 insertions(+)
diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index f41a72a..8e2e693 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -515,6 +515,48 @@ static int cmd_label(int argc, char **argv)
return get_label(argv[1]);
}
+static const char * const cmd_features_usage[] = {
+ "btrfs filesystem features [<device>|<mountpoint>] [[-f]
<features>]",
+ "Get or change the list of features currently enabled by a
filesystem",
+ "With one argument, get the currently enabled features of
filesystem",
+ "on <device> or <mountpoint>.", "",
+ "If <features> is passed, add or remove new features to the ",
+ "filesystem. The format of features can be a comma separated list
",
+ "of names or or a comma-separated list of specifiers of the
following",
+ "format: A prefix of compat, compat_ro, or incompat and a decimal",
+ "number, separated by a colon: (e.g. compat:10). Prefixing the ",
+ "feature name with a caret (^) will clear the flag.", "",
+ "The kernel has a defined set of feature flags that it will allow",
+ "to be set or cleared at runtime. Features not supported by the",
+ "tools can be changed by using the -f (force) flag when operating",
+ "on an unmounted filesystem.", "",
+ "A list of features supported by the tools can be found in the
manual.",
+ NULL
+};
+
+static int cmd_features(int argc, char **argv)
+{
+ if (check_argc_min(argc, 2) || check_argc_max(argc, 4))
+ usage(cmd_features_usage);
+
+ if (argc > 2) {
+ char *features = argv[2];
+ int force = 0;
+ if (argc > 3) {
+ if (!strcmp(argv[3], "-f"))
+ force = 1;
+ else if (!strcmp(argv[2], "-f")) {
+ force = 1;
+ features = argv[3];
+ } else
+ usage(cmd_features_usage);
+ }
+
+ return parse_and_set_features(argv[1], features, force);
+ } else
+ return get_features(argv[1]);
+}
+
const struct cmd_group filesystem_cmd_group = {
filesystem_cmd_group_usage, NULL, {
{ "df", cmd_df, cmd_df_usage, NULL, 0 },
@@ -524,6 +566,7 @@ const struct cmd_group filesystem_cmd_group = {
{ "balance", cmd_balance, NULL, &balance_cmd_group, 1 },
{ "resize", cmd_resize, cmd_resize_usage, NULL, 0 },
{ "label", cmd_label, cmd_label_usage, NULL, 0 },
+ { "features", cmd_features, cmd_features_usage, NULL, 0 },
{ 0, 0, 0, 0, 0 },
}
};
diff --git a/ioctl.h b/ioctl.h
index abe6dd4..3605c4a 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -172,6 +172,12 @@ struct btrfs_ioctl_fs_info_args {
__u64 reserved[124]; /* pad to 1k */
};
+struct btrfs_ioctl_feature_flags {
+ __u64 compat_flags;
+ __u64 compat_ro_flags;
+ __u64 incompat_flags;
+};
+
/* balance control ioctl modes */
#define BTRFS_BALANCE_CTL_PAUSE 1
#define BTRFS_BALANCE_CTL_CANCEL 2
@@ -537,6 +543,12 @@ struct btrfs_ioctl_clone_range_args {
struct btrfs_ioctl_get_dev_stats)
#define BTRFS_IOC_DEV_REPLACE _IOWR(BTRFS_IOCTL_MAGIC, 53, \
struct btrfs_ioctl_dev_replace_args)
+#define BTRFS_IOC_GET_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 54, \
+ struct btrfs_ioctl_feature_flags)
+#define BTRFS_IOC_SET_FEATURES _IOW(BTRFS_IOCTL_MAGIC, 54, \
+ struct btrfs_ioctl_feature_flags[2])
+#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 54, \
+ struct btrfs_ioctl_feature_flags[3])
#ifdef __cplusplus
}
diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index af7df4d..0b3815f 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -31,6 +31,8 @@ btrfs \- control a btrfs filesystem
.PP
\fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
.PP
+\fBbtrfs\fP \fBfilesystem features\fP\fI <dev|mountpoint> [[-f
]newlabel]\fP
+.PP
\fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
.PP
\fBbtrfs\fP \fBdevice scan\fP\fI [--all-devices|<device>
[<device>...]]\fP
@@ -280,6 +282,32 @@ NOTE: Currently there are the following limitations:
- the filesystem should not have more than one device.
.TP
+\fBfilesystem features\fP\fI <dev|mountpoint> [[-f] features]\fP
+Show or update the features of a filesystem. \fI<dev>\fR is used to
identify an umounted filesystem. \fI<mountpoint>\fR is used to identify a
mounted filesystem.
+If a \fIfeatures\fR optional argument is passed, the features are updated.
+The following features are currently supported by the tool:
+.br
+- mixed_backref
+.br
+- default_subvol
+.br
+- mixed_groups
+.br
+- compress_lzo
+.br
+- compress_lzov2
+.br
+- big_metadata
+.br
+- extended_iref
+.br
+- raid56
+.br
+- skinny_metadata
+.IP
+It is possible, but not recommended to set undocumented features using one of
the following prefixes: compat, compat_ro, incompat and a bit number, separated
by a colon. e.g. compat:12. Please note that changing unrecognized feature bits
is a dangerous operation and may result in an umountable file system that needs
to be manually repaired by an expert. It is also possible to clear a set flag by
prefixing the flag name with a caret (^).
+.TP
+
\fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
Show the btrfs filesystem with some additional info. If no \fIUUID\fP or
\fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
diff --git a/utils.c b/utils.c
index 7b4cd74..447ca9c 100644
--- a/utils.c
+++ b/utils.c
@@ -1350,6 +1350,594 @@ int set_label(const char *btrfs_dev, const char *label)
set_label_mounted(btrfs_dev, label);
}
+enum {
+ FEAT_COMPAT = 0,
+ FEAT_COMPAT_RO,
+ FEAT_INCOMPAT,
+};
+
+static const char * const feature_type[] = {
+ "compat",
+ "compat_ro",
+ "incompat",
+};
+
+static const char * const compat_features[] = {};
+static const char * const compat_ro_features[] = {};
+static const char * const incompat_features[] = {
+ "mixed_backref",
+ "default_subvol",
+ "mixed_groups",
+ "compress_lzo",
+ "compress_lzov2",
+ "big_metadata",
+ "extended_iref",
+ "raid56",
+ "skinny_metadata",
+};
+
+#define NAMEBUFSZ 4096 /* 64 names * 64 bytes/name (safe max) */
+static char *feature_names(int type, u64 flags)
+{
+ int i;
+ int name_count;
+ const char **names;
+ int count = 0;
+ char *buf = malloc(NAMEBUFSZ);
+ char *ptr = buf;
+ char typename[10]; /* compat_ro + 1 */
+
+ if (!buf)
+ return NULL;
+
+ *buf = 0;
+
+ switch (type) {
+ case FEAT_COMPAT:
+ name_count = ARRAY_SIZE(compat_features);
+ names = compat_features;
+ break;
+ case FEAT_COMPAT_RO:
+ name_count = ARRAY_SIZE(compat_ro_features);
+ names = compat_ro_features;
+ break;
+ case FEAT_INCOMPAT:
+ name_count = ARRAY_SIZE(incompat_features);
+ names = incompat_features;
+ break;
+ default:
+ BUG_ON(1);
+ };
+
+ strcpy(typename, feature_type[type]);
+ for (i = 0; i < sizeof(typename); i++)
+ typename[i] = tolower(typename[i]);
+
+ for (i = 0; i < sizeof(flags) << 3; i++) {
+ if (!(flags & (1ULL << i)))
+ continue;
+
+ if (i >= name_count)
+ ptr += snprintf(ptr, NAMEBUFSZ, "%s%s:%u",
+ count ? "," : "", typename, i);
+ else
+ ptr += snprintf(ptr, NAMEBUFSZ, "%s%s",
+ count ? "," : "", names[i]);
+ count++;
+
+ BUG_ON(ptr > buf + NAMEBUFSZ);
+ }
+
+ return buf;
+}
+
+static int print_features(const char *message,
+ struct btrfs_ioctl_feature_flags *flags)
+{
+ char *compat = NULL, *compat_ro = NULL, *incompat = NULL;
+
+ compat = feature_names(FEAT_COMPAT, flags->compat_flags);
+ compat_ro = feature_names(FEAT_COMPAT_RO, flags->compat_ro_flags);
+ incompat = feature_names(FEAT_INCOMPAT, flags->incompat_flags);
+ if (!compat || !compat_ro || !incompat)
+ goto enomem;
+
+ printf("%s: %s%s%s%s%s\n", message,
+ compat, compat[0] ? "," : "", compat_ro,
+ compat_ro[0] ? "," : "", incompat);
+
+ free(compat);
+ free(compat_ro);
+ free(incompat);
+
+ return 0;
+
+enomem:
+ fprintf(stderr,
+ "ERROR: Couldn''t allocate memory while printing
features.\n");
+ free(compat);
+ free(compat_ro);
+ free(incompat);
+ return -ENOMEM;
+}
+
+static int get_features_mounted(const char *mount_path)
+{
+ int fd;
+ struct btrfs_ioctl_feature_flags flags[3];
+ int ret;
+
+ fd = open(mount_path, O_RDONLY | O_DIRECTORY);
+ if (fd < 0) {
+ fprintf(stderr, "ERROR: unable to access ''%s'':
%s\n",
+ mount_path, strerror(errno));
+ return -1;
+ }
+
+ if (ioctl(fd, BTRFS_IOC_GET_SUPPORTED_FEATURES, &flags) < 0) {
+ ret = -errno;
+ fprintf(stderr,
+ "ERROR: unable to get supported features from kernel: %s\n",
+ strerror(errno));
+ close(fd);
+ return errno;
+ }
+
+ ret = print_features("Features supported by running kernel",
+ &flags[0]);
+ if (ret) {
+ close(fd);
+ return ret;
+ }
+
+ ret = print_features("Features that can be enabled by running
kernel",
+ &flags[1]);
+ if (ret) {
+ close(fd);
+ return ret;
+ }
+
+ ret = print_features("Features that can be cleared by running
kernel",
+ &flags[2]);
+ if (ret) {
+ close(fd);
+ return ret;
+ }
+
+ if (ioctl(fd, BTRFS_IOC_GET_FEATURES, &flags[0]) < 0) {
+ ret = -errno;
+ fprintf(stderr,
+ "ERROR: unable to get features from kernel: %s\n",
+ strerror(errno));
+ close(fd);
+ return ret;
+ }
+ close(fd);
+
+ return print_features("Features enabled on filesystem",
&flags[0]);
+}
+
+static int get_features_unmounted(const char *btrfs_dev)
+{
+ int ret;
+ struct btrfs_root *root;
+ struct btrfs_super_block *disk_super;
+ struct btrfs_ioctl_feature_flags flags;
+
+ ret = check_mounted(btrfs_dev);
+ if (ret < 0) {
+ fprintf(stderr, "FATAL: error checking %s mount status\n",
+ btrfs_dev);
+ return -1;
+ }
+ if (ret > 0) {
+ fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
+ btrfs_dev);
+ return -1;
+ }
+
+ /* Open the super_block at the default location
+ * and as read-only.
+ */
+ root = open_ctree(btrfs_dev, 0, 0);
+ if (!root)
+ return -1;
+
+ disk_super = root->fs_info->super_copy;
+
+ flags.compat_flags = btrfs_super_compat_flags(disk_super);
+ flags.compat_ro_flags = btrfs_super_compat_ro_flags(disk_super);
+ flags.incompat_flags = btrfs_super_incompat_flags(disk_super);
+
+ close_ctree(root);
+
+ return print_features("Features enabled on filesystem: ",
&flags);
+}
+
+int get_features(const char *btrfs_dev)
+{
+ return is_existing_blk_or_reg_file(btrfs_dev) ?
+ get_features_unmounted(btrfs_dev) :
+ get_features_mounted(btrfs_dev);
+
+}
+
+static int __check_feature_bits(const char *source,
+ int type, u64 change_mask,
+ u64 flags, u64 supported_flags,
+ u64 allowed_set, u64 allowed_clear,
+ int force)
+{
+ u64 unsupported, set, clear;
+ const char *errlevel = force ? "WARNING" : "ERROR";
+
+ unsupported = flags & change_mask & ~supported_flags;
+ if (unsupported) {
+ char *names = feature_names(type, unsupported);
+ if (names) {
+ fprintf(stderr,
+ "%s: %s does not support %s features: %s\n",
+ errlevel, source, feature_type[type], names);
+ free(names);
+ } else
+ fprintf(stderr,
+ "%s: %s does not support %s feature bits: %llx\n",
+ errlevel, source, feature_type[type],
+ unsupported);
+ }
+
+ set = flags & ~change_mask & allowed_set & ~unsupported;
+ if (set) {
+ char *names = feature_names(type, set);
+ if (names) {
+ fprintf(stderr,
+ "%s: %s does not support online setting of %s features: %s\n",
+ errlevel, source, feature_type[type], names);
+ free(names);
+ } else
+ fprintf(stderr,
+ "%s: %s does not support online setting of %s feature bits:
%llx\n",
+ errlevel, source, feature_type[type], set);
+ }
+
+ clear = ~flags & ~change_mask & allowed_clear & ~unsupported;
+ if (clear) {
+ char *names = feature_names(type, clear);
+ if (names) {
+ fprintf(stderr,
+ "%s: %s does not support online clearing of %s features: %s\n",
+ errlevel, source, feature_type[type], names);
+ free(names);
+ } else
+ fprintf(stderr,
+ "%s: %s does not support online clearing of %s feature bits:
%llx\n",
+ errlevel, source, feature_type[type], clear);
+ }
+
+ if (unsupported || set || clear) {
+ if (type == FEAT_INCOMPAT)
+ fprintf(stderr,
+ "Changing an unrecognized incompatible feature may result in a\nfile
system that must be manually repaired.\n");
+ return -1;
+ }
+ return 0;
+}
+
+#define check_feature_bits_mounted(a, b, c, d, e, f) \
+ __check_feature_bits("kernel", a, b, c, d, e, f, 0)
+
+#define check_feature_bits_unmounted(a, b, c, d, e) \
+ __check_feature_bits("progs", a, b, c, d, d, d, e)
+
+static int set_features_mounted(const char *mount_path,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags)
+{
+ int fd;
+ int ret;
+ struct btrfs_ioctl_feature_flags kernel_flags[3];
+ struct btrfs_ioctl_feature_flags our_flags[2];
+
+ fd = open(mount_path, O_RDONLY | O_NOATIME);
+ if (fd < 0) {
+ fprintf(stderr, "ERROR: unable to access ''%s'':
%s\n",
+ mount_path, strerror(errno));
+ return -1;
+ }
+
+ ret = ioctl(fd, BTRFS_IOC_GET_SUPPORTED_FEATURES, kernel_flags);
+ if (ret) {
+ fprintf(stderr,
+ "ERROR: unable to get the kernel''s supported feature list:
%s\n",
+ strerror(errno));
+ goto out;
+ }
+
+ /*
+ * The kernel will perform these checks as well. We repeat the checks
+ * in order to give the user something more helpful than -EPERM
+ * in the failure case.
+ */
+ ret = check_feature_bits_mounted(FEAT_COMPAT,
+ change_mask->compat_flags,
+ flags->compat_flags,
+ kernel_flags[0].compat_flags,
+ kernel_flags[1].compat_flags,
+ kernel_flags[2].compat_flags);
+
+ ret |= check_feature_bits_mounted(FEAT_COMPAT_RO,
+ change_mask->compat_ro_flags,
+ flags->compat_ro_flags,
+ kernel_flags[0].compat_ro_flags,
+ kernel_flags[1].compat_ro_flags,
+ kernel_flags[2].compat_ro_flags);
+
+ ret |= check_feature_bits_mounted(FEAT_INCOMPAT,
+ change_mask->incompat_flags,
+ flags->incompat_flags,
+ kernel_flags[0].incompat_flags,
+ kernel_flags[1].incompat_flags,
+ kernel_flags[2].incompat_flags);
+ if (ret)
+ goto out;
+
+ our_flags[0].compat_flags = change_mask->compat_flags;
+ our_flags[1].compat_flags = flags->compat_flags;
+ our_flags[0].compat_ro_flags = change_mask->compat_ro_flags;
+ our_flags[1].compat_ro_flags = flags->compat_ro_flags;
+ our_flags[0].incompat_flags = change_mask->incompat_flags;
+ our_flags[1].incompat_flags = flags->incompat_flags;
+
+ ret = ioctl(fd, BTRFS_IOC_SET_FEATURES, our_flags);
+ if (ret)
+ fprintf(stderr, "ERROR: failed to change features: %s\n",
+ strerror(errno));
+out:
+ close(fd);
+ return ret;
+}
+
+static int set_features_unmounted(const char *device,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags,
+ int force)
+{
+ struct btrfs_root *root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_super_block *disk_super;
+ u64 super_flags;
+ int ret;
+
+ ret = check_feature_bits_unmounted(FEAT_COMPAT,
+ change_mask->compat_flags,
+ flags->compat_flags,
+ BTRFS_FEATURE_COMPAT_SUPP,
+ force);
+ ret |= check_feature_bits_unmounted(FEAT_COMPAT_RO,
+ change_mask->compat_ro_flags,
+ flags->compat_ro_flags,
+ BTRFS_FEATURE_COMPAT_RO_SUPP,
+ force);
+ ret |= check_feature_bits_unmounted(FEAT_INCOMPAT,
+ change_mask->incompat_flags,
+ flags->incompat_flags,
+ BTRFS_FEATURE_INCOMPAT_SUPP,
+ force);
+
+ if (((change_mask->compat_flags & ~flags->compat_flags) ||
+ (change_mask->compat_ro_flags & ~flags->compat_ro_flags) ||
+ (change_mask->incompat_flags & ~flags->incompat_flags))
&&
+ !force) {
+ fprintf(stderr, "ERROR\nclearing flags is dangerous and requires the -f
option to continue.\nif clearing a flag that indicates the presence of an
on-disk feature\nthat is in use, serious corruption and/or crashes may
result.\nPROCEED WITH CAUTION.\n");
+ return -1;
+ }
+
+ if (ret && !force)
+ return 1;
+
+ ret = check_mounted(device);
+ if (ret < 0) {
+ fprintf(stderr, "FATAL: error checking %s mount status\n",
+ device);
+ return -1;
+ }
+ if (ret > 0) {
+ fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
+ device);
+ return -1;
+ }
+
+ root = open_ctree(device, 0, 1);
+ if (!root) {
+ fprintf(stderr, "Open ctree failed\n");
+ return 1;
+ }
+
+ disk_super = root->fs_info->super_copy;
+
+ trans = btrfs_start_transaction(root, 1);
+
+ super_flags = btrfs_super_compat_flags(disk_super);
+ super_flags |= (change_mask->compat_flags & flags->compat_flags);
+ super_flags &= ~(change_mask->compat_flags &
+ ~flags->compat_flags);
+ btrfs_set_super_compat_flags(disk_super, super_flags);
+
+ super_flags = btrfs_super_compat_ro_flags(disk_super);
+ super_flags |= (change_mask->compat_ro_flags &
flags->compat_ro_flags);
+ super_flags &= ~(change_mask->compat_ro_flags &
+ ~flags->compat_ro_flags);
+ btrfs_set_super_compat_ro_flags(disk_super, super_flags);
+
+ super_flags = btrfs_super_incompat_flags(disk_super);
+ super_flags |= (change_mask->incompat_flags &
flags->incompat_flags);
+ super_flags &= ~(change_mask->incompat_flags &
+ ~flags->incompat_flags);
+ btrfs_set_super_incompat_flags(disk_super, super_flags);
+
+ btrfs_commit_transaction(trans, root);
+
+ return 0;
+}
+
+static int parse_numbered_feature(const char *feature, int set,
+ struct btrfs_ioctl_feature_flags *change_mask,
+ struct btrfs_ioctl_feature_flags *flags)
+{
+ int ret = -1;
+ u64 *fptr = NULL;
+ u64 *mptr = NULL;
+ char *fname = strdup(feature);
+ char *colon = strchr(fname, '':'');
+ unsigned long num;
+
+ if (!colon)
+ goto fail;
+
+ *colon++ = 0;
+
+ num = strtoul(colon, NULL, 10);
+ if (num == ULONG_MAX) {
+ fprintf(stderr,
+ "ERROR: invalid numbered feature predicate: %s\n",
+ colon);
+ goto fail;
+ }
+
+ if (!strcmp(fname, "compat")) {
+ mptr = &change_mask->compat_flags;
+ fptr = &flags->compat_flags;
+ } else if (!strcmp(fname, "compat_ro")) {
+ mptr = &change_mask->compat_ro_flags;
+ fptr = &flags->compat_ro_flags;
+ } else if (!strcmp(fname, "incompat")) {
+ mptr = &change_mask->incompat_flags;
+ fptr = &flags->incompat_flags;
+ }
+
+ if (!fptr) {
+ fprintf(stderr,
+ "ERROR: invalid numbered feature prefix: %s\n", fname);
+
+ goto fail;
+ }
+
+ *mptr |= (1ULL << num);
+ if (set)
+ *fptr |= (1ULL << num);
+ else
+ *fptr &= ~(1ULL << num);
+
+ ret = 0;
+fail:
+ free(fname);
+ return ret;
+
+}
+
+int parse_features(const char *features,
+ struct btrfs_ioctl_feature_flags *change_mask,
+ struct btrfs_ioctl_feature_flags *flags)
+{
+ char *s, *ptr, *tmp;
+ int ret;
+
+ memset(change_mask, 0, sizeof(*change_mask));
+ memset(flags, 0, sizeof(*flags));
+
+ ptr = tmp = strdup(features);
+
+ while ((s = strsep(&tmp, ","))) {
+ int i;
+ int set = 1;
+ u64 bit;
+ if (s[0] == ''^'') {
+ set = 0;
+ s++;
+ }
+
+ if (strchr(s, '':'')) {
+ ret = parse_numbered_feature(s, set, change_mask,
+ flags);
+ if (ret)
+ goto out;
+ continue;
+ }
+ for (i = 0; i < ARRAY_SIZE(compat_features); i++) {
+ if (!strcmp(compat_features[i], s)) {
+ bit = (1ULL << i);
+ change_mask->compat_flags |= bit;
+ if (set)
+ flags->compat_flags |= bit;
+ else
+ flags->compat_flags &= ~bit;
+ s = NULL;
+ break;
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(compat_ro_features); i++) {
+ if (!strcmp(compat_ro_features[i], s)) {
+ bit = (1ULL << i);
+ change_mask->compat_ro_flags |= bit;
+ if (set)
+ flags->compat_ro_flags |= bit;
+ else
+ flags->compat_ro_flags &= ~bit;
+ s = NULL;
+ break;
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(incompat_features); i++) {
+ if (!strcmp(incompat_features[i], s)) {
+ bit = (1ULL << i);
+ change_mask->incompat_flags |= bit;
+ if (set)
+ flags->incompat_flags |= bit;
+ else
+ flags->incompat_flags &= ~bit;
+ s = NULL;
+ break;
+ }
+ }
+
+ if (s) {
+ fprintf(stderr, "ERROR: unknown named feature %s\n", s);
+ ret = -1;
+ goto out;
+ }
+ }
+
+ ret = 0;
+out:
+ free(ptr);
+ return ret;
+}
+
+int set_features(const char *dev,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags, int force)
+{
+ if (is_existing_blk_or_reg_file(dev))
+ return set_features_unmounted(dev, change_mask, flags, force);
+
+ return set_features_mounted(dev, change_mask, flags);
+}
+
+int parse_and_set_features(const char *btrfs_dev, const char *features,
+ int force)
+{
+ int ret;
+ struct btrfs_ioctl_feature_flags change_mask, flags;
+
+ ret = parse_features(features, &change_mask, &flags);
+ if (ret)
+ return ret;
+
+ return set_features(btrfs_dev, &change_mask, &flags, force);
+}
+
int btrfs_scan_block_devices(int run_ioctl)
{
diff --git a/utils.h b/utils.h
index 3c17e14..6faad28 100644
--- a/utils.h
+++ b/utils.h
@@ -55,6 +55,15 @@ int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args
*fi_args,
struct btrfs_ioctl_dev_info_args **di_ret);
int get_label(const char *btrfs_dev);
int set_label(const char *btrfs_dev, const char *label);
+int get_features(const char *btrfs_dev);
+int parse_features(const char *features,
+ struct btrfs_ioctl_feature_flags *change_mask,
+ struct btrfs_ioctl_feature_flags *flags);
+int set_features(const char *btrfs_dev,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags, int force);
+int parse_and_set_features(const char *btrfs_dev, const char *features,
+ int force);
char *__strncpy__null(char *dest, const char *src, size_t n);
int is_block_device(const char *file);
--
1.8.1.4
--
Jeff Mahoney
SUSE Labs
Jeff Mahoney
2013-Sep-10 04:34 UTC
[PATCH 2/2 v2] utils: add support for getting/changing file system, features
This patch adds support for getting and changing file system
feature bits. It supports both unmounted and mounted operation via
a new set of ioctls.
Changing bits not supported by the tools directly can be forced with -f
when the file system is unmounted.
v2: Implemented new ioctl methods from newer ioctl patchset; Cleanup
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
cmds-filesystem.c | 43 ++++
ioctl.h | 12 ++
man/btrfs.8.in | 28 +++
utils.c | 588 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
utils.h | 9 +
5 files changed, 680 insertions(+)
diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index f41a72a..8e2e693 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -515,6 +515,48 @@ static int cmd_label(int argc, char **argv)
return get_label(argv[1]);
}
+static const char * const cmd_features_usage[] = {
+ "btrfs filesystem features [<device>|<mountpoint>] [[-f]
<features>]",
+ "Get or change the list of features currently enabled by a
filesystem",
+ "With one argument, get the currently enabled features of
filesystem",
+ "on <device> or <mountpoint>.", "",
+ "If <features> is passed, add or remove new features to the ",
+ "filesystem. The format of features can be a comma separated list
",
+ "of names or or a comma-separated list of specifiers of the
following",
+ "format: A prefix of compat, compat_ro, or incompat and a decimal",
+ "number, separated by a colon: (e.g. compat:10). Prefixing the ",
+ "feature name with a caret (^) will clear the flag.", "",
+ "The kernel has a defined set of feature flags that it will allow",
+ "to be set or cleared at runtime. Features not supported by the",
+ "tools can be changed by using the -f (force) flag when operating",
+ "on an unmounted filesystem.", "",
+ "A list of features supported by the tools can be found in the
manual.",
+ NULL
+};
+
+static int cmd_features(int argc, char **argv)
+{
+ if (check_argc_min(argc, 2) || check_argc_max(argc, 4))
+ usage(cmd_features_usage);
+
+ if (argc > 2) {
+ char *features = argv[2];
+ int force = 0;
+ if (argc > 3) {
+ if (!strcmp(argv[3], "-f"))
+ force = 1;
+ else if (!strcmp(argv[2], "-f")) {
+ force = 1;
+ features = argv[3];
+ } else
+ usage(cmd_features_usage);
+ }
+
+ return parse_and_set_features(argv[1], features, force);
+ } else
+ return get_features(argv[1]);
+}
+
const struct cmd_group filesystem_cmd_group = {
filesystem_cmd_group_usage, NULL, {
{ "df", cmd_df, cmd_df_usage, NULL, 0 },
@@ -524,6 +566,7 @@ const struct cmd_group filesystem_cmd_group = {
{ "balance", cmd_balance, NULL, &balance_cmd_group, 1 },
{ "resize", cmd_resize, cmd_resize_usage, NULL, 0 },
{ "label", cmd_label, cmd_label_usage, NULL, 0 },
+ { "features", cmd_features, cmd_features_usage, NULL, 0 },
{ 0, 0, 0, 0, 0 },
}
};
diff --git a/ioctl.h b/ioctl.h
index abe6dd4..3605c4a 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -172,6 +172,12 @@ struct btrfs_ioctl_fs_info_args {
__u64 reserved[124]; /* pad to 1k */
};
+struct btrfs_ioctl_feature_flags {
+ __u64 compat_flags;
+ __u64 compat_ro_flags;
+ __u64 incompat_flags;
+};
+
/* balance control ioctl modes */
#define BTRFS_BALANCE_CTL_PAUSE 1
#define BTRFS_BALANCE_CTL_CANCEL 2
@@ -537,6 +543,12 @@ struct btrfs_ioctl_clone_range_args {
struct btrfs_ioctl_get_dev_stats)
#define BTRFS_IOC_DEV_REPLACE _IOWR(BTRFS_IOCTL_MAGIC, 53, \
struct btrfs_ioctl_dev_replace_args)
+#define BTRFS_IOC_GET_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 54, \
+ struct btrfs_ioctl_feature_flags)
+#define BTRFS_IOC_SET_FEATURES _IOW(BTRFS_IOCTL_MAGIC, 54, \
+ struct btrfs_ioctl_feature_flags[2])
+#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 54, \
+ struct btrfs_ioctl_feature_flags[3])
#ifdef __cplusplus
}
diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index af7df4d..0b3815f 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -31,6 +31,8 @@ btrfs \- control a btrfs filesystem
.PP
\fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
.PP
+\fBbtrfs\fP \fBfilesystem features\fP\fI <dev|mountpoint> [[-f
]newlabel]\fP
+.PP
\fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
.PP
\fBbtrfs\fP \fBdevice scan\fP\fI [--all-devices|<device>
[<device>...]]\fP
@@ -280,6 +282,32 @@ NOTE: Currently there are the following limitations:
- the filesystem should not have more than one device.
.TP
+\fBfilesystem features\fP\fI <dev|mountpoint> [[-f] features]\fP
+Show or update the features of a filesystem. \fI<dev>\fR is used to
identify an umounted filesystem. \fI<mountpoint>\fR is used to identify a
mounted filesystem.
+If a \fIfeatures\fR optional argument is passed, the features are updated.
+The following features are currently supported by the tool:
+.br
+- mixed_backref
+.br
+- default_subvol
+.br
+- mixed_groups
+.br
+- compress_lzo
+.br
+- compress_lzov2
+.br
+- big_metadata
+.br
+- extended_iref
+.br
+- raid56
+.br
+- skinny_metadata
+.IP
+It is possible, but not recommended to set undocumented features using one of
the following prefixes: compat, compat_ro, incompat and a bit number, separated
by a colon. e.g. compat:12. Please note that changing unrecognized feature bits
is a dangerous operation and may result in an umountable file system that needs
to be manually repaired by an expert. It is also possible to clear a set flag by
prefixing the flag name with a caret (^).
+.TP
+
\fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
Show the btrfs filesystem with some additional info. If no \fIUUID\fP or
\fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
diff --git a/utils.c b/utils.c
index 7b4cd74..447ca9c 100644
--- a/utils.c
+++ b/utils.c
@@ -1350,6 +1350,594 @@ int set_label(const char *btrfs_dev, const char *label)
set_label_mounted(btrfs_dev, label);
}
+enum {
+ FEAT_COMPAT = 0,
+ FEAT_COMPAT_RO,
+ FEAT_INCOMPAT,
+};
+
+static const char * const feature_type[] = {
+ "compat",
+ "compat_ro",
+ "incompat",
+};
+
+static const char * const compat_features[] = {};
+static const char * const compat_ro_features[] = {};
+static const char * const incompat_features[] = {
+ "mixed_backref",
+ "default_subvol",
+ "mixed_groups",
+ "compress_lzo",
+ "compress_lzov2",
+ "big_metadata",
+ "extended_iref",
+ "raid56",
+ "skinny_metadata",
+};
+
+#define NAMEBUFSZ 4096 /* 64 names * 64 bytes/name (safe max) */
+static char *feature_names(int type, u64 flags)
+{
+ int i;
+ int name_count;
+ const char **names;
+ int count = 0;
+ char *buf = malloc(NAMEBUFSZ);
+ char *ptr = buf;
+ char typename[10]; /* compat_ro + 1 */
+
+ if (!buf)
+ return NULL;
+
+ *buf = 0;
+
+ switch (type) {
+ case FEAT_COMPAT:
+ name_count = ARRAY_SIZE(compat_features);
+ names = compat_features;
+ break;
+ case FEAT_COMPAT_RO:
+ name_count = ARRAY_SIZE(compat_ro_features);
+ names = compat_ro_features;
+ break;
+ case FEAT_INCOMPAT:
+ name_count = ARRAY_SIZE(incompat_features);
+ names = incompat_features;
+ break;
+ default:
+ BUG_ON(1);
+ };
+
+ strcpy(typename, feature_type[type]);
+ for (i = 0; i < sizeof(typename); i++)
+ typename[i] = tolower(typename[i]);
+
+ for (i = 0; i < sizeof(flags) << 3; i++) {
+ if (!(flags & (1ULL << i)))
+ continue;
+
+ if (i >= name_count)
+ ptr += snprintf(ptr, NAMEBUFSZ, "%s%s:%u",
+ count ? "," : "", typename, i);
+ else
+ ptr += snprintf(ptr, NAMEBUFSZ, "%s%s",
+ count ? "," : "", names[i]);
+ count++;
+
+ BUG_ON(ptr > buf + NAMEBUFSZ);
+ }
+
+ return buf;
+}
+
+static int print_features(const char *message,
+ struct btrfs_ioctl_feature_flags *flags)
+{
+ char *compat = NULL, *compat_ro = NULL, *incompat = NULL;
+
+ compat = feature_names(FEAT_COMPAT, flags->compat_flags);
+ compat_ro = feature_names(FEAT_COMPAT_RO, flags->compat_ro_flags);
+ incompat = feature_names(FEAT_INCOMPAT, flags->incompat_flags);
+ if (!compat || !compat_ro || !incompat)
+ goto enomem;
+
+ printf("%s: %s%s%s%s%s\n", message,
+ compat, compat[0] ? "," : "", compat_ro,
+ compat_ro[0] ? "," : "", incompat);
+
+ free(compat);
+ free(compat_ro);
+ free(incompat);
+
+ return 0;
+
+enomem:
+ fprintf(stderr,
+ "ERROR: Couldn''t allocate memory while printing
features.\n");
+ free(compat);
+ free(compat_ro);
+ free(incompat);
+ return -ENOMEM;
+}
+
+static int get_features_mounted(const char *mount_path)
+{
+ int fd;
+ struct btrfs_ioctl_feature_flags flags[3];
+ int ret;
+
+ fd = open(mount_path, O_RDONLY | O_DIRECTORY);
+ if (fd < 0) {
+ fprintf(stderr, "ERROR: unable to access ''%s'':
%s\n",
+ mount_path, strerror(errno));
+ return -1;
+ }
+
+ if (ioctl(fd, BTRFS_IOC_GET_SUPPORTED_FEATURES, &flags) < 0) {
+ ret = -errno;
+ fprintf(stderr,
+ "ERROR: unable to get supported features from kernel: %s\n",
+ strerror(errno));
+ close(fd);
+ return errno;
+ }
+
+ ret = print_features("Features supported by running kernel",
+ &flags[0]);
+ if (ret) {
+ close(fd);
+ return ret;
+ }
+
+ ret = print_features("Features that can be enabled by running
kernel",
+ &flags[1]);
+ if (ret) {
+ close(fd);
+ return ret;
+ }
+
+ ret = print_features("Features that can be cleared by running
kernel",
+ &flags[2]);
+ if (ret) {
+ close(fd);
+ return ret;
+ }
+
+ if (ioctl(fd, BTRFS_IOC_GET_FEATURES, &flags[0]) < 0) {
+ ret = -errno;
+ fprintf(stderr,
+ "ERROR: unable to get features from kernel: %s\n",
+ strerror(errno));
+ close(fd);
+ return ret;
+ }
+ close(fd);
+
+ return print_features("Features enabled on filesystem",
&flags[0]);
+}
+
+static int get_features_unmounted(const char *btrfs_dev)
+{
+ int ret;
+ struct btrfs_root *root;
+ struct btrfs_super_block *disk_super;
+ struct btrfs_ioctl_feature_flags flags;
+
+ ret = check_mounted(btrfs_dev);
+ if (ret < 0) {
+ fprintf(stderr, "FATAL: error checking %s mount status\n",
+ btrfs_dev);
+ return -1;
+ }
+ if (ret > 0) {
+ fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
+ btrfs_dev);
+ return -1;
+ }
+
+ /* Open the super_block at the default location
+ * and as read-only.
+ */
+ root = open_ctree(btrfs_dev, 0, 0);
+ if (!root)
+ return -1;
+
+ disk_super = root->fs_info->super_copy;
+
+ flags.compat_flags = btrfs_super_compat_flags(disk_super);
+ flags.compat_ro_flags = btrfs_super_compat_ro_flags(disk_super);
+ flags.incompat_flags = btrfs_super_incompat_flags(disk_super);
+
+ close_ctree(root);
+
+ return print_features("Features enabled on filesystem: ",
&flags);
+}
+
+int get_features(const char *btrfs_dev)
+{
+ return is_existing_blk_or_reg_file(btrfs_dev) ?
+ get_features_unmounted(btrfs_dev) :
+ get_features_mounted(btrfs_dev);
+
+}
+
+static int __check_feature_bits(const char *source,
+ int type, u64 change_mask,
+ u64 flags, u64 supported_flags,
+ u64 allowed_set, u64 allowed_clear,
+ int force)
+{
+ u64 unsupported, set, clear;
+ const char *errlevel = force ? "WARNING" : "ERROR";
+
+ unsupported = flags & change_mask & ~supported_flags;
+ if (unsupported) {
+ char *names = feature_names(type, unsupported);
+ if (names) {
+ fprintf(stderr,
+ "%s: %s does not support %s features: %s\n",
+ errlevel, source, feature_type[type], names);
+ free(names);
+ } else
+ fprintf(stderr,
+ "%s: %s does not support %s feature bits: %llx\n",
+ errlevel, source, feature_type[type],
+ unsupported);
+ }
+
+ set = flags & ~change_mask & allowed_set & ~unsupported;
+ if (set) {
+ char *names = feature_names(type, set);
+ if (names) {
+ fprintf(stderr,
+ "%s: %s does not support online setting of %s features: %s\n",
+ errlevel, source, feature_type[type], names);
+ free(names);
+ } else
+ fprintf(stderr,
+ "%s: %s does not support online setting of %s feature bits:
%llx\n",
+ errlevel, source, feature_type[type], set);
+ }
+
+ clear = ~flags & ~change_mask & allowed_clear & ~unsupported;
+ if (clear) {
+ char *names = feature_names(type, clear);
+ if (names) {
+ fprintf(stderr,
+ "%s: %s does not support online clearing of %s features: %s\n",
+ errlevel, source, feature_type[type], names);
+ free(names);
+ } else
+ fprintf(stderr,
+ "%s: %s does not support online clearing of %s feature bits:
%llx\n",
+ errlevel, source, feature_type[type], clear);
+ }
+
+ if (unsupported || set || clear) {
+ if (type == FEAT_INCOMPAT)
+ fprintf(stderr,
+ "Changing an unrecognized incompatible feature may result in a\nfile
system that must be manually repaired.\n");
+ return -1;
+ }
+ return 0;
+}
+
+#define check_feature_bits_mounted(a, b, c, d, e, f) \
+ __check_feature_bits("kernel", a, b, c, d, e, f, 0)
+
+#define check_feature_bits_unmounted(a, b, c, d, e) \
+ __check_feature_bits("progs", a, b, c, d, d, d, e)
+
+static int set_features_mounted(const char *mount_path,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags)
+{
+ int fd;
+ int ret;
+ struct btrfs_ioctl_feature_flags kernel_flags[3];
+ struct btrfs_ioctl_feature_flags our_flags[2];
+
+ fd = open(mount_path, O_RDONLY | O_NOATIME);
+ if (fd < 0) {
+ fprintf(stderr, "ERROR: unable to access ''%s'':
%s\n",
+ mount_path, strerror(errno));
+ return -1;
+ }
+
+ ret = ioctl(fd, BTRFS_IOC_GET_SUPPORTED_FEATURES, kernel_flags);
+ if (ret) {
+ fprintf(stderr,
+ "ERROR: unable to get the kernel''s supported feature list:
%s\n",
+ strerror(errno));
+ goto out;
+ }
+
+ /*
+ * The kernel will perform these checks as well. We repeat the checks
+ * in order to give the user something more helpful than -EPERM
+ * in the failure case.
+ */
+ ret = check_feature_bits_mounted(FEAT_COMPAT,
+ change_mask->compat_flags,
+ flags->compat_flags,
+ kernel_flags[0].compat_flags,
+ kernel_flags[1].compat_flags,
+ kernel_flags[2].compat_flags);
+
+ ret |= check_feature_bits_mounted(FEAT_COMPAT_RO,
+ change_mask->compat_ro_flags,
+ flags->compat_ro_flags,
+ kernel_flags[0].compat_ro_flags,
+ kernel_flags[1].compat_ro_flags,
+ kernel_flags[2].compat_ro_flags);
+
+ ret |= check_feature_bits_mounted(FEAT_INCOMPAT,
+ change_mask->incompat_flags,
+ flags->incompat_flags,
+ kernel_flags[0].incompat_flags,
+ kernel_flags[1].incompat_flags,
+ kernel_flags[2].incompat_flags);
+ if (ret)
+ goto out;
+
+ our_flags[0].compat_flags = change_mask->compat_flags;
+ our_flags[1].compat_flags = flags->compat_flags;
+ our_flags[0].compat_ro_flags = change_mask->compat_ro_flags;
+ our_flags[1].compat_ro_flags = flags->compat_ro_flags;
+ our_flags[0].incompat_flags = change_mask->incompat_flags;
+ our_flags[1].incompat_flags = flags->incompat_flags;
+
+ ret = ioctl(fd, BTRFS_IOC_SET_FEATURES, our_flags);
+ if (ret)
+ fprintf(stderr, "ERROR: failed to change features: %s\n",
+ strerror(errno));
+out:
+ close(fd);
+ return ret;
+}
+
+static int set_features_unmounted(const char *device,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags,
+ int force)
+{
+ struct btrfs_root *root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_super_block *disk_super;
+ u64 super_flags;
+ int ret;
+
+ ret = check_feature_bits_unmounted(FEAT_COMPAT,
+ change_mask->compat_flags,
+ flags->compat_flags,
+ BTRFS_FEATURE_COMPAT_SUPP,
+ force);
+ ret |= check_feature_bits_unmounted(FEAT_COMPAT_RO,
+ change_mask->compat_ro_flags,
+ flags->compat_ro_flags,
+ BTRFS_FEATURE_COMPAT_RO_SUPP,
+ force);
+ ret |= check_feature_bits_unmounted(FEAT_INCOMPAT,
+ change_mask->incompat_flags,
+ flags->incompat_flags,
+ BTRFS_FEATURE_INCOMPAT_SUPP,
+ force);
+
+ if (((change_mask->compat_flags & ~flags->compat_flags) ||
+ (change_mask->compat_ro_flags & ~flags->compat_ro_flags) ||
+ (change_mask->incompat_flags & ~flags->incompat_flags))
&&
+ !force) {
+ fprintf(stderr, "ERROR\nclearing flags is dangerous and requires the -f
option to continue.\nif clearing a flag that indicates the presence of an
on-disk feature\nthat is in use, serious corruption and/or crashes may
result.\nPROCEED WITH CAUTION.\n");
+ return -1;
+ }
+
+ if (ret && !force)
+ return 1;
+
+ ret = check_mounted(device);
+ if (ret < 0) {
+ fprintf(stderr, "FATAL: error checking %s mount status\n",
+ device);
+ return -1;
+ }
+ if (ret > 0) {
+ fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
+ device);
+ return -1;
+ }
+
+ root = open_ctree(device, 0, 1);
+ if (!root) {
+ fprintf(stderr, "Open ctree failed\n");
+ return 1;
+ }
+
+ disk_super = root->fs_info->super_copy;
+
+ trans = btrfs_start_transaction(root, 1);
+
+ super_flags = btrfs_super_compat_flags(disk_super);
+ super_flags |= (change_mask->compat_flags & flags->compat_flags);
+ super_flags &= ~(change_mask->compat_flags &
+ ~flags->compat_flags);
+ btrfs_set_super_compat_flags(disk_super, super_flags);
+
+ super_flags = btrfs_super_compat_ro_flags(disk_super);
+ super_flags |= (change_mask->compat_ro_flags &
flags->compat_ro_flags);
+ super_flags &= ~(change_mask->compat_ro_flags &
+ ~flags->compat_ro_flags);
+ btrfs_set_super_compat_ro_flags(disk_super, super_flags);
+
+ super_flags = btrfs_super_incompat_flags(disk_super);
+ super_flags |= (change_mask->incompat_flags &
flags->incompat_flags);
+ super_flags &= ~(change_mask->incompat_flags &
+ ~flags->incompat_flags);
+ btrfs_set_super_incompat_flags(disk_super, super_flags);
+
+ btrfs_commit_transaction(trans, root);
+
+ return 0;
+}
+
+static int parse_numbered_feature(const char *feature, int set,
+ struct btrfs_ioctl_feature_flags *change_mask,
+ struct btrfs_ioctl_feature_flags *flags)
+{
+ int ret = -1;
+ u64 *fptr = NULL;
+ u64 *mptr = NULL;
+ char *fname = strdup(feature);
+ char *colon = strchr(fname, '':'');
+ unsigned long num;
+
+ if (!colon)
+ goto fail;
+
+ *colon++ = 0;
+
+ num = strtoul(colon, NULL, 10);
+ if (num == ULONG_MAX) {
+ fprintf(stderr,
+ "ERROR: invalid numbered feature predicate: %s\n",
+ colon);
+ goto fail;
+ }
+
+ if (!strcmp(fname, "compat")) {
+ mptr = &change_mask->compat_flags;
+ fptr = &flags->compat_flags;
+ } else if (!strcmp(fname, "compat_ro")) {
+ mptr = &change_mask->compat_ro_flags;
+ fptr = &flags->compat_ro_flags;
+ } else if (!strcmp(fname, "incompat")) {
+ mptr = &change_mask->incompat_flags;
+ fptr = &flags->incompat_flags;
+ }
+
+ if (!fptr) {
+ fprintf(stderr,
+ "ERROR: invalid numbered feature prefix: %s\n", fname);
+
+ goto fail;
+ }
+
+ *mptr |= (1ULL << num);
+ if (set)
+ *fptr |= (1ULL << num);
+ else
+ *fptr &= ~(1ULL << num);
+
+ ret = 0;
+fail:
+ free(fname);
+ return ret;
+
+}
+
+int parse_features(const char *features,
+ struct btrfs_ioctl_feature_flags *change_mask,
+ struct btrfs_ioctl_feature_flags *flags)
+{
+ char *s, *ptr, *tmp;
+ int ret;
+
+ memset(change_mask, 0, sizeof(*change_mask));
+ memset(flags, 0, sizeof(*flags));
+
+ ptr = tmp = strdup(features);
+
+ while ((s = strsep(&tmp, ","))) {
+ int i;
+ int set = 1;
+ u64 bit;
+ if (s[0] == ''^'') {
+ set = 0;
+ s++;
+ }
+
+ if (strchr(s, '':'')) {
+ ret = parse_numbered_feature(s, set, change_mask,
+ flags);
+ if (ret)
+ goto out;
+ continue;
+ }
+ for (i = 0; i < ARRAY_SIZE(compat_features); i++) {
+ if (!strcmp(compat_features[i], s)) {
+ bit = (1ULL << i);
+ change_mask->compat_flags |= bit;
+ if (set)
+ flags->compat_flags |= bit;
+ else
+ flags->compat_flags &= ~bit;
+ s = NULL;
+ break;
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(compat_ro_features); i++) {
+ if (!strcmp(compat_ro_features[i], s)) {
+ bit = (1ULL << i);
+ change_mask->compat_ro_flags |= bit;
+ if (set)
+ flags->compat_ro_flags |= bit;
+ else
+ flags->compat_ro_flags &= ~bit;
+ s = NULL;
+ break;
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(incompat_features); i++) {
+ if (!strcmp(incompat_features[i], s)) {
+ bit = (1ULL << i);
+ change_mask->incompat_flags |= bit;
+ if (set)
+ flags->incompat_flags |= bit;
+ else
+ flags->incompat_flags &= ~bit;
+ s = NULL;
+ break;
+ }
+ }
+
+ if (s) {
+ fprintf(stderr, "ERROR: unknown named feature %s\n", s);
+ ret = -1;
+ goto out;
+ }
+ }
+
+ ret = 0;
+out:
+ free(ptr);
+ return ret;
+}
+
+int set_features(const char *dev,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags, int force)
+{
+ if (is_existing_blk_or_reg_file(dev))
+ return set_features_unmounted(dev, change_mask, flags, force);
+
+ return set_features_mounted(dev, change_mask, flags);
+}
+
+int parse_and_set_features(const char *btrfs_dev, const char *features,
+ int force)
+{
+ int ret;
+ struct btrfs_ioctl_feature_flags change_mask, flags;
+
+ ret = parse_features(features, &change_mask, &flags);
+ if (ret)
+ return ret;
+
+ return set_features(btrfs_dev, &change_mask, &flags, force);
+}
+
int btrfs_scan_block_devices(int run_ioctl)
{
diff --git a/utils.h b/utils.h
index 3c17e14..6faad28 100644
--- a/utils.h
+++ b/utils.h
@@ -55,6 +55,15 @@ int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args
*fi_args,
struct btrfs_ioctl_dev_info_args **di_ret);
int get_label(const char *btrfs_dev);
int set_label(const char *btrfs_dev, const char *label);
+int get_features(const char *btrfs_dev);
+int parse_features(const char *features,
+ struct btrfs_ioctl_feature_flags *change_mask,
+ struct btrfs_ioctl_feature_flags *flags);
+int set_features(const char *btrfs_dev,
+ const struct btrfs_ioctl_feature_flags *change_mask,
+ const struct btrfs_ioctl_feature_flags *flags, int force);
+int parse_and_set_features(const char *btrfs_dev, const char *features,
+ int force);
char *__strncpy__null(char *dest, const char *src, size_t n);
int is_block_device(const char *file);
--
1.8.1.4
--
Jeff Mahoney
SUSE Labs
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