--- a/lib/yaffs2/direct/yportenv.h
+++ b/lib/yaffs2/direct/yportenv.h
@@ -32,10 +32,13 @@
 #define CONFIG_YAFFS_DEFINES_TYPES 1
 #define CONFIG_YAFFS_USE_32_BIT_TIME_T 1
 #define NO_Y_INLINE 1
-#define loff_t off_t
 
 #endif /* __rtems__ */
 
+#ifndef linux
+#define loff_t off_t
+#endif
+
 /* Definition of types */
 #ifdef CONFIG_YAFFS_DEFINES_TYPES
 typedef unsigned char u8;
--- a/src/ioctl.c
+++ b/src/ioctl.c
@@ -21,5 +21,9 @@
  * integer overflow when building against e.g. musl.
  */
 int linux_ioctl(int fd, unsigned long request, void *ptr) {
+#ifdef linux
 	return syscall(SYS_ioctl, fd, request, ptr);
+#else
+	return -1;
+#endif
 }
--- a/src/ioctl.h
+++ b/src/ioctl.h
@@ -12,7 +12,9 @@ int linux_ioctl(int fd, unsigned long re
  * time, as the definition of the MEMREAD ioctl trickles down into kernel
  * headers distributed out there.
  */
+#ifdef linux
 #include <mtd/mtd-user.h>
+
 #ifndef MEMREAD
 #include <sys/ioctl.h>
 
@@ -35,3 +37,4 @@ struct mtd_read_req {
 
 #define MEMREAD _IOWR('M', 26, struct mtd_read_req)
 #endif /* MEMREAD */
+#endif
--- a/src/mtd.c
+++ b/src/mtd.c
@@ -4,7 +4,9 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#ifdef linux
 #include <mtd/mtd-user.h>
+#endif
 #include <stdarg.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -82,6 +84,7 @@ static void mtd_debug_location(const cha
 	va_end(args);
 }
 
+#ifdef linux
 /*
  * Read the raw contents of the sysfs attribute at the provided 'sysfs_path'
  * into 'buf', which is 'buf_len' bytes large.  The given sysfs attribute is
@@ -179,6 +182,7 @@ static int discover_mtd_parameters(const
 
 	return 0;
 }
+#endif
 
 /*
  * Initialize 'geometry' with 'chunk_size' and 'block_size' set to the default
@@ -203,6 +207,7 @@ static void init_yaffs_geometry_default(
  * Initialize 'geometry' with 'chunk_size' and 'block_size' set to the relevant
  * MTD parameters provided in 'mtd' and 'mtd_type' set to the provided value.
  */
+#ifdef linux
 static void init_yaffs_geometry_autodetected(const struct mtd_ctx *ctx,
 					     const struct mtd_info_user *mtd,
 					     struct mtd_geometry *geometry,
@@ -217,6 +222,7 @@ static void init_yaffs_geometry_autodete
 		.block_size = mtd->erasesize,
 	};
 }
+#endif
 
 /*
  * Update 'chunk_size' and 'block_size' in 'geometry' to the values provided in
@@ -280,6 +286,7 @@ static int init_yaffs_geometry_file(cons
  *  2. If -C and/or -B were used, override any default values with those
  *     provided on the command line.
  */
+#ifdef linux
 static void init_yaffs_geometry_nand_or_nor(const struct mtd_ctx *ctx,
 					    const struct mtd_info_user *mtd,
 					    const struct opts *opts,
@@ -297,6 +304,7 @@ static void init_yaffs_geometry_nand_or_
 
 	geometry->block_count = mtd->size / geometry->block_size;
 }
+#endif
 
 /*
  * Determine the type of the provided MTD (which can be either NAND/NOR flash
@@ -317,6 +325,7 @@ static int init_yaffs_geometry(const str
 		geometry->oob_size = 0;
 		geometry->oobavail = 0;
 	} else {
+#ifdef linux
 		struct mtd_info_user mtd;
 		unsigned int oobavail;
 
@@ -329,6 +338,9 @@ static int init_yaffs_geometry(const str
 
 		geometry->oob_size = mtd.oobsize;
 		geometry->oobavail = oobavail;
+#else
+		return -1;
+#endif
 	}
 
 	return 0;
--- a/src/ydrv.c
+++ b/src/ydrv.c
@@ -3,7 +3,9 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
 #include <errno.h>
+#ifdef linux
 #include <mtd/mtd-user.h>
+#endif
 #include <stdarg.h>
 #include <stdbool.h>
 #include <stdint.h>
@@ -122,6 +124,7 @@ static long long ydrv_get_data_offset_fo
 /*
  * Check whether the given MTD block is a bad one on NAND or NOR flash.
  */
+#ifdef linux
 static int ydrv_check_bad_nand_or_nor(const struct ydrv_ctx *ctx,
 				      int block_no) {
 	long long offset = block_no * ctx->block_size;
@@ -139,6 +142,7 @@ static int ydrv_check_bad_nand_or_nor(co
 
 	return (ret == 0 ? YAFFS_OK : YAFFS_FAIL);
 }
+#endif
 
 /*
  * Check whether the given MTD block is a bad one.
@@ -154,9 +158,11 @@ static int ydrv_check_bad(struct yaffs_d
 	}
 
 	switch (ctx->mtd_type) {
+#ifdef linux
 	case MTD_TYPE_NAND:
 	case MTD_TYPE_NOR:
 		return ydrv_check_bad_nand_or_nor(ctx, block_no);
+#endif
 	case MTD_TYPE_FILE:
 		ydrv_debug("file is assumed to only contain good blocks");
 		return YAFFS_OK;
@@ -169,6 +175,7 @@ static int ydrv_check_bad(struct yaffs_d
 /*
  * Erase the given MTD block on NAND or NOR flash.
  */
+#ifdef linux
 static int ydrv_erase_block_nand_or_nor(const struct ydrv_ctx *ctx,
 					int block_no) {
 	long long offset = block_no * ctx->block_size;
@@ -196,6 +203,7 @@ static int ydrv_erase_block_nand_or_nor(
 
 	return YAFFS_OK;
 }
+#endif
 
 /*
  * Erase the given MTD block in a file.
@@ -247,9 +255,11 @@ static int ydrv_erase_block(struct yaffs
 	}
 
 	switch (ctx->mtd_type) {
+#ifdef linux
 	case MTD_TYPE_NAND:
 	case MTD_TYPE_NOR:
 		return ydrv_erase_block_nand_or_nor(ctx, block_no);
+#endif
 	case MTD_TYPE_FILE:
 		return ydrv_erase_block_file(ctx, block_no);
 	default:
@@ -261,6 +271,7 @@ static int ydrv_erase_block(struct yaffs
 /*
  * Mark the given MTD block as bad on NAND or NOR flash.
  */
+#ifdef linux
 static int ydrv_mark_bad_nand_or_nor(const struct ydrv_ctx *ctx, int block_no) {
 	long long offset = block_no * ctx->block_size;
 	int err = 0;
@@ -281,6 +292,7 @@ static int ydrv_mark_bad_nand_or_nor(con
 
 	return YAFFS_OK;
 }
+#endif
 
 /*
  * Mark the given MTD block as bad.
@@ -296,9 +308,11 @@ static int ydrv_mark_bad(struct yaffs_de
 	}
 
 	switch (ctx->mtd_type) {
+#ifdef linux
 	case MTD_TYPE_NAND:
 	case MTD_TYPE_NOR:
 		return ydrv_mark_bad_nand_or_nor(ctx, block_no);
+#endif
 	case MTD_TYPE_FILE:
 		ydrv_debug("file is assumed to only contain good blocks");
 		return YAFFS_FAIL;
@@ -315,9 +329,11 @@ static int ydrv_mark_bad(struct yaffs_de
  */
 static int ydrv_ecc_result(int read_result, enum yaffs_ecc_result *ecc_result) {
 	switch (read_result) {
+#ifdef linux
 	case -EUCLEAN:
 		*ecc_result = YAFFS_ECC_RESULT_FIXED;
 		return YAFFS_OK;
+#endif
 	case -EBADMSG:
 		*ecc_result = YAFFS_ECC_RESULT_UNFIXED;
 		return YAFFS_FAIL;
@@ -333,6 +349,7 @@ static int ydrv_ecc_result(int read_resu
 /*
  * Read a data+OOB chunk from NAND flash.
  */
+#ifdef linux
 static int ydrv_read_chunk_nand(const struct ydrv_ctx *ctx, int chunk, u8 *data,
 				int data_len, u8 *oob, int oob_len,
 				enum yaffs_ecc_result *ecc_result_out,
@@ -371,6 +388,7 @@ static int ydrv_read_chunk_nand(const st
 
 	return ret;
 }
+#endif
 
 /*
  * Read a data chunk from NOR flash.
@@ -420,10 +438,12 @@ static int ydrv_read_chunk(struct yaffs_
 	}
 
 	switch (ctx->mtd_type) {
+#ifdef linux
 	case MTD_TYPE_NAND:
 		return ydrv_read_chunk_nand(ctx, chunk, data, data_len, oob,
 					    oob_len, ecc_result_out,
 					    dev->param.is_yaffs2);
+#endif
 	case MTD_TYPE_NOR:
 	case MTD_TYPE_FILE:
 		return ydrv_read_chunk_nor_or_file(ctx, chunk, data, data_len,
@@ -438,6 +458,7 @@ static int ydrv_read_chunk(struct yaffs_
 /*
  * Write a data+OOB chunk to NAND flash.
  */
+#ifdef linux
 static int ydrv_write_chunk_nand(const struct ydrv_ctx *ctx, int chunk,
 				 const u8 *data, int data_len, const u8 *oob,
 				 int oob_len, bool is_yaffs2) {
@@ -472,6 +493,7 @@ static int ydrv_write_chunk_nand(const s
 
 	return YAFFS_OK;
 }
+#endif
 
 /*
  * Write a data chunk to NOR flash.
@@ -516,9 +538,11 @@ static int ydrv_write_chunk(struct yaffs
 	}
 
 	switch (ctx->mtd_type) {
+#ifdef linux
 	case MTD_TYPE_NAND:
 		return ydrv_write_chunk_nand(ctx, chunk, data, data_len, oob,
 					     oob_len, dev->param.is_yaffs2);
+#endif
 	case MTD_TYPE_NOR:
 	case MTD_TYPE_FILE:
 		return ydrv_write_chunk_nor_or_file(ctx, chunk, data, data_len);