#define DEFAULT_SECTOR_SIZE 512
-#if !defined(BLKROSET) && defined(__linux__)
-
-#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
-#define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
-#define BLKRRPART _IO(0x12,95) /* re-read partition table */
-#define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
-#define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
-#define BLKRASET _IO(0x12,98) /* set read ahead for block device */
-#define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
-#define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
-#define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
-#define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
-#define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
-#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
+#ifdef __linux__
+/* very basic ioclts, should be available everywhere */
+# ifndef BLKROSET
+# define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
+# define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
+# define BLKRRPART _IO(0x12,95) /* re-read partition table */
+# define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
+# define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
+# define BLKRASET _IO(0x12,98) /* set read ahead for block device */
+# define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
+# define BLKFRASET _IO(0x12,100) /* set filesystem (mm/filemap.c) read-ahead */
+# define BLKFRAGET _IO(0x12,101) /* get filesystem (mm/filemap.c) read-ahead */
+# define BLKSECTSET _IO(0x12,102) /* set max sectors per request (ll_rw_blk.c) */
+# define BLKSECTGET _IO(0x12,103) /* get max sectors per request (ll_rw_blk.c) */
+# define BLKSSZGET _IO(0x12,104) /* get block device sector size */
/* ioctls introduced in 2.2.16, removed in 2.5.58 */
-#define BLKELVGET _IOR(0x12,106,size_t) /* elevator get */
-#define BLKELVSET _IOW(0x12,107,size_t) /* elevator set */
+# define BLKELVGET _IOR(0x12,106,size_t) /* elevator get */
+# define BLKELVSET _IOW(0x12,107,size_t) /* elevator set */
-#define BLKBSZGET _IOR(0x12,112,size_t)
-#define BLKBSZSET _IOW(0x12,113,size_t)
-#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
+# define BLKBSZGET _IOR(0x12,112,size_t)
+# define BLKBSZSET _IOW(0x12,113,size_t)
+# endif /* !BLKROSET */
-#endif /* BLKROSET && __linux__ */
+# ifndef BLKGETSIZE64
+# define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
+# endif
+/* block device topology ioctls, introduced in 2.6.32 (commit ac481c20) */
+# ifndef BLKIOMIN
+# define BLKIOMIN _IO(0x12,120)
+# define BLKIOOPT _IO(0x12,121)
+# define BLKALIGNOFF _IO(0x12,122)
+# define BLKPBSZGET _IO(0x12,123)
+# endif
-#ifdef APPLE_DARWIN
-#define BLKGETSIZE DKIOCGETBLOCKCOUNT32
-#endif
+/* discard zeroes support, introduced in 2.6.33 (commit 98262f27) */
+# ifndef BLKDISCARDZEROES
+# define BLKDISCARDZEROES _IO(0x12,124)
+# endif
-/* block device topology ioctls, introduced in 2.6.32 */
-#ifndef BLKIOMIN
-#define BLKIOMIN _IO(0x12,120)
-#define BLKIOOPT _IO(0x12,121)
-#define BLKALIGNOFF _IO(0x12,122)
-#define BLKPBSZGET _IO(0x12,123)
-#endif
+/* filesystem freeze, introduced in 2.6.29 (commit fcccf502) */
+# ifndef FIFREEZE
+# define FIFREEZE _IOWR('X', 119, int) /* Freeze */
+# define FITHAW _IOWR('X', 120, int) /* Thaw */
+# endif
-/* discard zeroes support, introduced in 2.6.33 (commait 98262f27) */
-#ifndef BLKDISCARDZEROES
-#define BLKDISCARDZEROES _IO(0x12,124)
-#endif
+#endif /* __linux */
-#ifndef FIFREEZE
-#define FIFREEZE _IOWR('X', 119, int) /* Freeze */
-#define FITHAW _IOWR('X', 120, int) /* Thaw */
+#ifdef APPLE_DARWIN
+# define BLKGETSIZE DKIOCGETBLOCKCOUNT32
#endif
#ifndef HDIO_GETGEO