diff --git a/src/urma/hw/udma/kernel_headers/udma_abi.h b/src/urma/hw/udma/kernel_headers/udma_abi.h
index 3cc1e7b9fd8d7cc2f27bff56e4f177bf76f0e3a7..257962765d5aab447ac116b6ce4858d62f4a7194 100644
--- a/src/urma/hw/udma/kernel_headers/udma_abi.h
+++ b/src/urma/hw/udma/kernel_headers/udma_abi.h
@@ -6,9 +6,9 @@
 
 #include <linux/types.h>
 
-#define MAP_COMMAND_MASK 0xff
-#define MAP_INDEX_MASK 0xffffff
-#define MAP_INDEX_SHIFT 8
+#define MAP_COMMAND_MASK 0xf
+#define MAP_INDEX_MASK 0xfffffff
+#define MAP_INDEX_SHIFT 4
 
 #define UDMA_SEGMENT_ACCESS_GUARD (1UL << 5)
 
@@ -85,7 +85,7 @@ struct udma_create_jetty_ucmd {
 struct udma_create_jfc_ucmd {
 	__aligned_u64 buf_addr;
 	__u32 buf_len;
-	__u32 mode; /* 0: normal, 1: user STARS mode, 2: kernel STARS mode */
+	__u32 mode; /* 0: normal, 1: user stars, 2: kernel stars */
 	__aligned_u64 db_addr;
 	__u32 is_hugepage : 1;
 	__u32 rsv : 31;
@@ -112,9 +112,9 @@ struct udma_create_jfr_resp {
 };
 
 enum db_mmap_type {
+	UDMA_MMAP_HUGEPAGE,
 	UDMA_MMAP_JFC_PAGE,
 	UDMA_MMAP_JETTY_DSQE,
-	UDMA_MMAP_HUGEPAGE,
 };
 
 enum {
diff --git a/src/urma/hw/udma/udma_u_buf.c b/src/urma/hw/udma/udma_u_buf.c
index 5200c4b3a45a124832d3e7e7d54f5d88d3e3fcac..edfe893854d1781abffdda49f7af87a32e8da56a 100644
--- a/src/urma/hw/udma/udma_u_buf.c
+++ b/src/urma/hw/udma/udma_u_buf.c
@@ -130,7 +130,7 @@ static void udma_u_hugepage_del(struct udma_u_context *ctx,
 static struct udma_u_hugepage_priv *
 udma_u_alloc_hugepage_priv(struct udma_u_context *ctx, uint32_t len)
 {
-	off_t offset = get_mmap_offset(0, ctx->page_size, UDMA_MMAP_HUGEPAGE);
+	off_t offset = get_mmap_offset((UDMA_HUGEPAGE_SIZE / ctx->page_size >> MAP_INDEX_SHIFT), ctx->page_size, UDMA_MMAP_HUGEPAGE);
 	struct udma_u_hugepage_priv *priv;
 	int ret;