btrfs-progs: move fs features implementation to own file

Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 227 insertions, 0 deletions

diff --git a/fsfeatures.c b/fsfeatures.c
new file mode 100644
index 00000000..7d85d60f
--- /dev/null
+++ b/fsfeatures.c
@@ -0,0 +1,227 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include "kerncompat.h"
+#include <sys/utsname.h>
+#include <linux/version.h>
+#include "fsfeatures.h"
+#include "ctree.h"
+#include "utils.h"
+
+/*
+ * Insert a root item for temporary tree root
+ *
+ * Only used in make_btrfs_v2().
+ */
+#define VERSION_TO_STRING3(a,b,c)	#a "." #b "." #c, KERNEL_VERSION(a,b,c)
+#define VERSION_TO_STRING2(a,b)		#a "." #b, KERNEL_VERSION(a,b,0)
+
+/*
+ * Feature stability status and versions: compat <= safe <= default
+ */
+static const struct btrfs_fs_feature {
+	const char *name;
+	u64 flag;
+	const char *sysfs_name;
+	/*
+	 * Compatibility with kernel of given version. Filesystem can be
+	 * mounted.
+	 */
+	const char *compat_str;
+	u32 compat_ver;
+	/*
+	 * Considered safe for use, but is not on by default, even if the
+	 * kernel supports the feature.
+	 */
+	const char *safe_str;
+	u32 safe_ver;
+	/*
+	 * Considered safe for use and will be turned on by default if
+	 * supported by the running kernel.
+	 */
+	const char *default_str;
+	u32 default_ver;
+	const char *desc;
+} mkfs_features[] = {
+	{ "mixed-bg", BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS,
+		"mixed_groups",
+		VERSION_TO_STRING3(2,6,37),
+		VERSION_TO_STRING3(2,6,37),
+		NULL, 0,
+		"mixed data and metadata block groups" },
+	{ "extref", BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF,
+		"extended_iref",
+		VERSION_TO_STRING2(3,7),
+		VERSION_TO_STRING2(3,12),
+		VERSION_TO_STRING2(3,12),
+		"increased hardlink limit per file to 65536" },
+	{ "raid56", BTRFS_FEATURE_INCOMPAT_RAID56,
+		"raid56",
+		VERSION_TO_STRING2(3,9),
+		NULL, 0,
+		NULL, 0,
+		"raid56 extended format" },
+	{ "skinny-metadata", BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA,
+		"skinny_metadata",
+		VERSION_TO_STRING2(3,10),
+		VERSION_TO_STRING2(3,18),
+		VERSION_TO_STRING2(3,18),
+		"reduced-size metadata extent refs" },
+	{ "no-holes", BTRFS_FEATURE_INCOMPAT_NO_HOLES,
+		"no_holes",
+		VERSION_TO_STRING2(3,14),
+		VERSION_TO_STRING2(4,0),
+		NULL, 0,
+		"no explicit hole extents for files" },
+	/* Keep this one last */
+	{ "list-all", BTRFS_FEATURE_LIST_ALL, NULL }
+};
+
+static int parse_one_fs_feature(const char *name, u64 *flags)
+{
+	int i;
+	int found = 0;
+
+	for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) {
+		if (name[0] == '^' &&
+			!strcmp(mkfs_features[i].name, name + 1)) {
+			*flags &= ~ mkfs_features[i].flag;
+			found = 1;
+		} else if (!strcmp(mkfs_features[i].name, name)) {
+			*flags |= mkfs_features[i].flag;
+			found = 1;
+		}
+	}
+
+	return !found;
+}
+
+void btrfs_parse_features_to_string(char *buf, u64 flags)
+{
+	int i;
+
+	buf[0] = 0;
+
+	for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) {
+		if (flags & mkfs_features[i].flag) {
+			if (*buf)
+				strcat(buf, ", ");
+			strcat(buf, mkfs_features[i].name);
+		}
+	}
+}
+
+void btrfs_process_fs_features(u64 flags)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) {
+		if (flags & mkfs_features[i].flag) {
+			printf("Turning ON incompat feature '%s': %s\n",
+				mkfs_features[i].name,
+				mkfs_features[i].desc);
+		}
+	}
+}
+
+void btrfs_list_all_fs_features(u64 mask_disallowed)
+{
+	int i;
+
+	fprintf(stderr, "Filesystem features available:\n");
+	for (i = 0; i < ARRAY_SIZE(mkfs_features) - 1; i++) {
+		const struct btrfs_fs_feature *feat = &mkfs_features[i];
+
+		if (feat->flag & mask_disallowed)
+			continue;
+		fprintf(stderr, "%-20s- %s (0x%llx", feat->name, feat->desc,
+				feat->flag);
+		if (feat->compat_ver)
+			fprintf(stderr, ", compat=%s", feat->compat_str);
+		if (feat->safe_ver)
+			fprintf(stderr, ", safe=%s", feat->safe_str);
+		if (feat->default_ver)
+			fprintf(stderr, ", default=%s", feat->default_str);
+		fprintf(stderr, ")\n");
+	}
+}
+
+/*
+ * Return NULL if all features were parsed fine, otherwise return the name of
+ * the first unparsed.
+ */
+char* btrfs_parse_fs_features(char *namelist, u64 *flags)
+{
+	char *this_char;
+	char *save_ptr = NULL; /* Satisfy static checkers */
+
+	for (this_char = strtok_r(namelist, ",", &save_ptr);
+	     this_char != NULL;
+	     this_char = strtok_r(NULL, ",", &save_ptr)) {
+		if (parse_one_fs_feature(this_char, flags))
+			return this_char;
+	}
+
+	return NULL;
+}
+
+void print_kernel_version(FILE *stream, u32 version)
+{
+	u32 v[3];
+
+	v[0] = version & 0xFF;
+	v[1] = (version >> 8) & 0xFF;
+	v[2] = version >> 16;
+	fprintf(stream, "%u.%u", v[2], v[1]);
+	if (v[0])
+		fprintf(stream, ".%u", v[0]);
+}
+
+u32 get_running_kernel_version(void)
+{
+	struct utsname utsbuf;
+	char *tmp;
+	char *saveptr = NULL;
+	u32 version;
+
+	uname(&utsbuf);
+	if (strcmp(utsbuf.sysname, "Linux") != 0) {
+		error("unsupported system: %s", utsbuf.sysname);
+		exit(1);
+	}
+	/* 1.2.3-4-name */
+	tmp = strchr(utsbuf.release, '-');
+	if (tmp)
+		*tmp = 0;
+
+	tmp = strtok_r(utsbuf.release, ".", &saveptr);
+	if (!string_is_numerical(tmp))
+		return (u32)-1;
+	version = atoi(tmp) << 16;
+	tmp = strtok_r(NULL, ".", &saveptr);
+	if (!string_is_numerical(tmp))
+		return (u32)-1;
+	version |= atoi(tmp) << 8;
+	tmp = strtok_r(NULL, ".", &saveptr);
+	if (tmp) {
+		if (!string_is_numerical(tmp))
+			return (u32)-1;
+		version |= atoi(tmp);
+	}
+
+	return version;
+}
+