linux-user: Fix target_semid_ds structure definition

The target_semid_ds structure is not correct for all
architectures: the padding fields should only exist for:
 * 32-bit ABIs
 * x86

It is also misnamed, since it is following the kernel
semid64_ds structure (QEMU doesn't support the legacy
semid_ds structure at all). Rename the struct, provide
a correct generic definition and allow the oddball x86
architecture to provide its own version.

This fixes broken SYSV semaphores for all our 64-bit
architectures except x86 and ppc.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

linux-user/syscall.c

@@ -3754,27 +3754,30 @@ static struct shm_region {
     bool in_use;
 } shm_regions[N_SHM_REGIONS];
 
-struct target_semid_ds
+#ifndef TARGET_SEMID64_DS
+/* asm-generic version of this struct */
+struct target_semid64_ds
 {
   struct target_ipc_perm sem_perm;
   abi_ulong sem_otime;
-#if !defined(TARGET_PPC64)
+#if TARGET_ABI_BITS == 32
   abi_ulong __unused1;
 #endif
   abi_ulong sem_ctime;
-#if !defined(TARGET_PPC64)
+#if TARGET_ABI_BITS == 32
   abi_ulong __unused2;
 #endif
   abi_ulong sem_nsems;
   abi_ulong __unused3;
   abi_ulong __unused4;
 };
+#endif
 
 static inline abi_long target_to_host_ipc_perm(struct ipc_perm *host_ip,
                                                abi_ulong target_addr)
 {
     struct target_ipc_perm *target_ip;
-    struct target_semid_ds *target_sd;
+    struct target_semid64_ds *target_sd;
 
     if (!lock_user_struct(VERIFY_READ, target_sd, target_addr, 1))
         return -TARGET_EFAULT;
@@ -3802,7 +3805,7 @@ static inline abi_long host_to_target_ipc_perm(abi_ulong target_addr,
                                                struct ipc_perm *host_ip)
 {
     struct target_ipc_perm *target_ip;
-    struct target_semid_ds *target_sd;
+    struct target_semid64_ds *target_sd;
 
     if (!lock_user_struct(VERIFY_WRITE, target_sd, target_addr, 0))
         return -TARGET_EFAULT;
@@ -3829,7 +3832,7 @@ static inline abi_long host_to_target_ipc_perm(abi_ulong target_addr,
 static inline abi_long target_to_host_semid_ds(struct semid_ds *host_sd,
                                                abi_ulong target_addr)
 {
-    struct target_semid_ds *target_sd;
+    struct target_semid64_ds *target_sd;
 
     if (!lock_user_struct(VERIFY_READ, target_sd, target_addr, 1))
         return -TARGET_EFAULT;
@@ -3845,7 +3848,7 @@ static inline abi_long target_to_host_semid_ds(struct semid_ds *host_sd,
 static inline abi_long host_to_target_semid_ds(abi_ulong target_addr,
                                                struct semid_ds *host_sd)
 {
-    struct target_semid_ds *target_sd;
+    struct target_semid64_ds *target_sd;
 
     if (!lock_user_struct(VERIFY_WRITE, target_sd, target_addr, 0))
         return -TARGET_EFAULT;

linux-user/x86_64/target_structs.h

@@ -55,4 +55,19 @@ struct target_shmid_ds {
     abi_ulong __unused5;
 };
 
+/* The x86 definition differs from the generic one in that the
+ * two padding fields exist whether the ABI is 32 bits or 64 bits.
+ */
+#define TARGET_SEMID64_DS
+struct target_semid64_ds {
+    struct target_ipc_perm sem_perm;
+    abi_ulong sem_otime;
+    abi_ulong __unused1;
+    abi_ulong sem_ctime;
+    abi_ulong __unused2;
+    abi_ulong sem_nsems;
+    abi_ulong __unused3;
+    abi_ulong __unused4;
+};
+
 #endif