Add xattr .totl. tag

Add the .totl. xattr tag.  When the tag is set the end of the name
specifies a total name with 3 encoded u64s separated by dots.  The value
of the xattr is a u64 that is added to the named total.   An ioctl is
added to read the totals.

Signed-off-by: Zach Brown <zab@versity.com>

utils/src/print.c

@@ -75,6 +75,17 @@ static void print_orphan(struct scoutfs_key *key, void *val, int val_len)
 	printf("    orphan: ino %llu\n", le64_to_cpu(key->sko_ino));
 }
 
+
+static void print_xattr_totl(struct scoutfs_key *key, void *val, int val_len)
+{
+	struct scoutfs_xattr_totl_val *tval = val;
+
+	printf("    xattr totl: %llu.%llu.%llu = %lld, %lld\n",
+	       le64_to_cpu(key->skxt_a), le64_to_cpu(key->skxt_b),
+	       le64_to_cpu(key->skxt_c), le64_to_cpu(tval->total),
+	       le64_to_cpu(tval->count));
+}
+
 static u8 *global_printable_name(u8 *name, int name_len)
 {
 	static u8 name_buf[SCOUTFS_NAME_LEN + 1];
@@ -163,6 +174,9 @@ static print_func_t find_printer(u8 zone, u8 type)
 			return print_orphan;
 	}
 
+	if (zone == SCOUTFS_XATTR_TOTL_ZONE)
+		return print_xattr_totl;
+
 	if (zone == SCOUTFS_FS_ZONE) {
 		switch(type) {
 			case SCOUTFS_INODE_TYPE: return print_inode;

utils/src/read_xattr_totals.c

@@ -0,0 +1,120 @@
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <argp.h>
+
+#include "sparse.h"
+#include "parse.h"
+#include "util.h"
+#include "format.h"
+#include "ioctl.h"
+#include "cmd.h"
+
+struct xattr_args {
+	char *path;
+};
+
+static int do_read_xattr_totals(struct xattr_args *args)
+{
+	struct scoutfs_ioctl_read_xattr_totals rxt;
+	struct scoutfs_ioctl_xattr_total *xts = NULL;
+	struct scoutfs_ioctl_xattr_total *xt;
+	u64 bytes = 1024 * 1024;
+	int fd = -1;
+	int ret;
+	int i;
+
+	xts = malloc(bytes);
+	if (!xts) {
+		fprintf(stderr, "xattr total mem alloc failed\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	fd = get_path(args->path, O_RDONLY);
+	if (fd < 0)
+		return fd;
+
+	memset(&rxt, 0, sizeof(rxt));
+	rxt.totals_ptr = (unsigned long)xts;
+	rxt.totals_bytes = bytes;
+
+	for (;;) {
+		ret = ioctl(fd, SCOUTFS_IOC_READ_XATTR_TOTALS, &rxt);
+		if (ret == 0)
+			break;
+		if (ret < 0) {
+			ret = -errno;
+			fprintf(stderr, "read_xattr_totals ioctl failed: "
+				"%s (%d)\n", strerror(errno), errno);
+			goto out;
+		}
+
+		for (i = 0, xt = xts; i < ret; i++, xt++)
+			printf("%llu.%llu.%llu = %lld, %lld\n",
+				xt->name[0], xt->name[1], xt->name[2], xt->total, xt->count);
+
+		memcpy(&rxt.pos_name, &xts[ret - 1].name, sizeof(rxt.pos_name));
+		if (++rxt.pos_name[2] == 0 && ++rxt.pos_name[1] == 0 && ++rxt.pos_name[0] == 0)
+			break;
+	}
+
+	ret = 0;
+out:
+	if (fd >= 0)
+		close(fd);
+	free(xts);
+
+	return ret;
+};
+
+static int parse_opt(int key, char *arg, struct argp_state *state)
+{
+	struct xattr_args *args = state->input;
+
+	switch (key) {
+	case 'p':
+		args->path = strdup_or_error(state, arg);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static struct argp_option options[] = {
+	{ "path", 'p', "PATH", 0, "Path to ScoutFS filesystem"},
+	{ NULL }
+};
+
+static struct argp argp = {
+	options,
+	parse_opt,
+	"",
+	"Print global value totals of .totl. xattrs"
+};
+
+static int read_xattr_totals_cmd(int argc, char **argv)
+{
+
+	struct xattr_args xattr_args = {NULL};
+	int ret;
+
+	ret = argp_parse(&argp, argc, argv, 0, NULL, &xattr_args);
+	if (ret)
+		return ret;
+
+	return do_read_xattr_totals(&xattr_args);
+}
+
+static void __attribute__((constructor)) read_xattr_totals_ctor(void)
+{
+	cmd_register_argp("read-xattr-totals", &argp, GROUP_INFO, read_xattr_totals_cmd);
+}