Refactor user util functions for device size

Split the existing device_size() into get_device_size() and
limit_device_size().  An upcoming command wants to get the device size
without applying limiting policy.

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

utils/src/dev.c

@@ -12,13 +12,10 @@
 #include "sparse.h"
 #include "dev.h"
 
-int device_size(char *path, int fd,
+int get_device_size(char *path, int fd, u64 *size_ret)
-		u64 min_size, u64 max_size, bool allow_small_size,
-		char *use_type, u64 *size_ret)
 {
 	struct stat st;
 	u64 size;
-	char *target_type;
 	int ret;
 
 	if (fstat(fd, &st)) {
@@ -30,7 +27,6 @@ int device_size(char *path, int fd,
 
 	if (S_ISREG(st.st_mode)) {
 		size = st.st_size;
-		target_type = "file";
 	} else if (S_ISBLK(st.st_mode)) {
 		if (ioctl(fd, BLKGETSIZE64, &size)) {
 			ret = -errno;
@@ -38,13 +34,26 @@ int device_size(char *path, int fd,
 				path, strerror(errno), errno);
 			return ret;
 		}
-		target_type = "device";
 	} else {
 		fprintf(stderr, "path isn't regular or device file '%s'\n",
 			path);
 		return -EINVAL;
 	}
 
+	*size_ret = size;
+	return 0;
+}
+
+int limit_device_size(char *path, int fd, u64 min_size, u64 max_size, bool allow_small_size,
+		      char *use_type, u64 *size_ret)
+{
+	u64 size;
+	int ret;
+
+	ret = get_device_size(path, fd, &size);
+	if (ret < 0)
+		return ret;
+
 	if (max_size) {
 		if (size > max_size) {
 			printf("Limiting use of "BASE_SIZE_FMT
@@ -64,9 +73,9 @@ int device_size(char *path, int fd,
 
 	if (size < min_size) {
 		fprintf(stderr,
-			BASE_SIZE_FMT" %s too small for min "
+			BASE_SIZE_FMT" too small for min "
 			BASE_SIZE_FMT" %s device%s\n",
-			BASE_SIZE_ARGS(size), target_type,
+			BASE_SIZE_ARGS(size),
 			BASE_SIZE_ARGS(min_size), use_type,
 			allow_small_size ? ", allowing with -A" : "");
 

utils/src/dev.h

@@ -9,9 +9,9 @@
 #define SIZE_FMT "%llu (%.2f %s)"
 #define SIZE_ARGS(nr, sz) (nr), size_flt(nr, sz), size_str(nr, sz)
 
-int device_size(char *path, int fd,
+int get_device_size(char *path, int fd, u64 *size_ret);
-		u64 min_size, u64 max_size, bool allow_small_size,
+int limit_device_size(char *path, int fd, u64 min_size, u64 max_size, bool allow_small_size,
-		char *use_type, u64 *size_ret);
+		      char *use_type, u64 *size_ret);
 float size_flt(u64 nr, unsigned size);
 char *size_str(u64 nr, unsigned size);
 int flush_device(int fd);

utils/src/mkfs.c

@@ -206,14 +206,14 @@ static int do_mkfs(struct mkfs_args *args)
 	}
 
 	/* minumum meta device size to make reserved blocks reasonably large */
-	ret = device_size(args->meta_device, meta_fd, 64ULL * (1024 * 1024 * 1024),
+	ret = limit_device_size(args->meta_device, meta_fd, 64ULL * (1024 * 1024 * 1024),
-			  args->max_meta_size, args->allow_small_size, "meta", &meta_size);
+				args->max_meta_size, args->allow_small_size, "meta", &meta_size);
 	if (ret)
 		goto out;
 
 	/* .. then arbitrarily the same minimum data device size */
-	ret = device_size(args->data_device, data_fd, 64ULL * (1024 * 1024 * 1024),
+	ret = limit_device_size(args->data_device, data_fd, 64ULL * (1024 * 1024 * 1024),
-			  args->max_data_size, args->allow_small_size, "data", &data_size);
+				args->max_data_size, args->allow_small_size, "data", &data_size);
 	if (ret)
 		goto out;