linux-user: Fix TARGET_MTIOCTOP/MTIOCGET/MTIOCPOS values

The TARGET_MTIOCTOP/TARGET_MTIOCGET/TARGET_MTIOCPOS values
were being defined in terms of host struct types, but
these structures are such that their size might differ
on different hosts. Switch to using a target struct
definition instead.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

linux-user/syscall_defs.h

@@ -2712,9 +2712,34 @@ struct target_f_owner_ex {
 #define TARGET_VFAT_IOCTL_READDIR_BOTH    TARGET_IORU('r', 1)
 #define TARGET_VFAT_IOCTL_READDIR_SHORT   TARGET_IORU('r', 2)
 
-#define TARGET_MTIOCTOP        TARGET_IOW('m', 1, struct mtop)
-#define TARGET_MTIOCGET        TARGET_IOR('m', 2, struct mtget)
-#define TARGET_MTIOCPOS        TARGET_IOR('m', 3, struct mtpos)
+struct target_mtop {
+    abi_short mt_op;
+    abi_int mt_count;
+};
+
+#if defined(TARGET_SPARC) || defined(TARGET_MIPS)
+typedef abi_long target_kernel_daddr_t;
+#else
+typedef abi_int target_kernel_daddr_t;
+#endif
+
+struct target_mtget {
+    abi_long mt_type;
+    abi_long mt_resid;
+    abi_long mt_dsreg;
+    abi_long mt_gstat;
+    abi_long mt_erreg;
+    target_kernel_daddr_t mt_fileno;
+    target_kernel_daddr_t mt_blkno;
+};
+
+struct target_mtpos {
+    abi_long mt_blkno;
+};
+
+#define TARGET_MTIOCTOP        TARGET_IOW('m', 1, struct target_mtop)
+#define TARGET_MTIOCGET        TARGET_IOR('m', 2, struct target_mtget)
+#define TARGET_MTIOCPOS        TARGET_IOR('m', 3, struct target_mtpos)
 
 struct target_sysinfo {
     abi_long uptime;                /* Seconds since boot */