Index: util-linux-2.29/include/loopdev.h
===================================================================
--- util-linux-2.29.orig/include/loopdev.h
+++ util-linux-2.29/include/loopdev.h
@@ -41,6 +41,7 @@ enum {
 	LO_FLAGS_AUTOCLEAR  = 4,	/* kernel >= 2.6.25 */
 	LO_FLAGS_PARTSCAN   = 8,	/* kernel >= 3.2 */
 	LO_FLAGS_DIRECT_IO  = 16,	/* kernel >= 4.2 */
+	LO_FLAGS_BLOCKSIZE  = 32,       /* Tentative */
 };
 
 #define LO_NAME_SIZE	64
@@ -120,7 +121,8 @@ enum {
 	LOOPDEV_FL_NOIOCTL	= (1 << 6),
 	LOOPDEV_FL_DEVSUBDIR	= (1 << 7),
 	LOOPDEV_FL_CONTROL	= (1 << 8),	/* system with /dev/loop-control */
-	LOOPDEV_FL_SIZELIMIT	= (1 << 9)
+	LOOPDEV_FL_SIZELIMIT	= (1 << 9),
+	LOOPDEV_FL_BLOCKSIZE	= (1 << 10)
 };
 
 /*
@@ -173,6 +175,7 @@ int loopcxt_set_offset(struct loopdev_cx
 int loopcxt_set_sizelimit(struct loopdev_cxt *lc, uint64_t sizelimit);
 int loopcxt_set_flags(struct loopdev_cxt *lc, uint32_t flags);
 int loopcxt_set_backing_file(struct loopdev_cxt *lc, const char *filename);
+int loopcxt_set_blocksize(struct loopdev_cxt *lc, uint64_t blocksize);
 
 extern char *loopcxt_get_backing_file(struct loopdev_cxt *lc);
 extern int loopcxt_get_backing_devno(struct loopdev_cxt *lc, dev_t *devno);
Index: util-linux-2.29/lib/loopdev.c
===================================================================
--- util-linux-2.29.orig/lib/loopdev.c
+++ util-linux-2.29/lib/loopdev.c
@@ -1115,6 +1115,26 @@ int loopcxt_set_backing_file(struct loop
 }
 
 /*
+ * @lc: context
+ * @blocksize: logical blocksize for the device
+ *
+ * The setting is removed by loopcxt_set_device() loopcxt_next()!
+ *
+ * Returns: 0 on success, <0 on error.
+ */
+int loopcxt_set_blocksize(struct loopdev_cxt *lc, uint64_t blocksize)
+{
+	if (!lc)
+		return -EINVAL;
+
+	lc->info.lo_init[0] = blocksize;
+	lc->info.lo_flags |= LO_FLAGS_BLOCKSIZE;
+
+	DBG(CXT, ul_debugobj(lc, "set blocksize=%llu", (long long unsigned int)lc->info.lo_init[0]));
+	return 0;
+}
+
+/*
  * In kernels prior to v3.9, if the offset or sizelimit options
  * are used, the block device's size won't be synced automatically.
  * blockdev --getsize64 and filesystems will use the backing
Index: util-linux-2.29/sys-utils/losetup.c
===================================================================
--- util-linux-2.29.orig/sys-utils/losetup.c
+++ util-linux-2.29/sys-utils/losetup.c
@@ -398,6 +398,7 @@ static void usage(FILE *out)
 
 	fputs(_(" -o, --offset <num>            start at offset <num> into file\n"), out);
 	fputs(_("     --sizelimit <num>         device is limited to <num> bytes of the file\n"), out);
+	fputs(_("     --logical-blocksize <size> set the logical block size to <size>\n"), out);
 	fputs(_(" -P, --partscan                create a partitioned loop device\n"), out);
 	fputs(_(" -r, --read-only               set up a read-only loop device\n"), out);
 	fputs(_("     --direct-io[=<on|off>]    open backing file with O_DIRECT\n"), out);
@@ -447,7 +448,8 @@ static void warn_size(const char *filena
 
 static int create_loop(struct loopdev_cxt *lc,
 		       int nooverlap, int lo_flags, int flags,
-		       const char *file, uint64_t offset, uint64_t sizelimit)
+		       const char *file, uint64_t offset, uint64_t sizelimit,
+		       uint64_t blocksize)
 {
 	int hasdev = loopcxt_has_device(lc);
 	int rc = 0;
@@ -533,6 +535,8 @@ static int create_loop(struct loopdev_cx
 			loopcxt_set_offset(lc, offset);
 		if (flags & LOOPDEV_FL_SIZELIMIT)
 			loopcxt_set_sizelimit(lc, sizelimit);
+		if (flags & LOOPDEV_FL_BLOCKSIZE)
+			loopcxt_set_blocksize(lc, blocksize);
 		if (lo_flags)
 			loopcxt_set_flags(lc, lo_flags);
 		if ((rc = loopcxt_set_backing_file(lc, file))) {
@@ -561,7 +565,7 @@ int main(int argc, char **argv)
 	struct loopdev_cxt lc;
 	int act = 0, flags = 0, no_overlap = 0, c;
 	char *file = NULL;
-	uint64_t offset = 0, sizelimit = 0;
+	uint64_t offset = 0, sizelimit = 0, blocksize = 0;
 	int res = 0, showdev = 0, lo_flags = 0;
 	char *outarg = NULL;
 	int list = 0;
@@ -571,7 +575,8 @@ int main(int argc, char **argv)
 		OPT_SIZELIMIT = CHAR_MAX + 1,
 		OPT_SHOW,
 		OPT_RAW,
-		OPT_DIO
+		OPT_DIO,
+		OPT_BLOCKSIZE,
 	};
 	static const struct option longopts[] = {
 		{ "all", 0, 0, 'a' },
@@ -584,6 +589,7 @@ int main(int argc, char **argv)
 		{ "associated", 1, 0, 'j' },
 		{ "json", 0, 0, 'J' },
 		{ "list", 0, 0, 'l' },
+		{ "logical-blocksize", 1, 0, OPT_BLOCKSIZE },
 		{ "noheadings", 0, 0, 'n' },
 		{ "offset", 1, 0, 'o' },
 		{ "output", 1, 0, 'O' },
@@ -657,6 +663,10 @@ int main(int argc, char **argv)
 			act = A_SHOW;
 			file = optarg;
 			break;
+		case OPT_BLOCKSIZE:
+			blocksize = strtosize_or_err(optarg, _("failed to parse logical block size"));
+			flags |= LOOPDEV_FL_BLOCKSIZE;
+			break;
 		case 'l':
 			list = 1;
 			break;
@@ -789,7 +799,8 @@ int main(int argc, char **argv)
 
 	switch (act) {
 	case A_CREATE:
-		res = create_loop(&lc, no_overlap, lo_flags, flags, file, offset, sizelimit);
+		res = create_loop(&lc, no_overlap, lo_flags, flags, file, offset,
+				  sizelimit, blocksize);
 		if (res == 0) {
 			if (showdev)
 				printf("%s\n", loopcxt_get_device(&lc));