fs/quota: use COMPAT_SYSCALL_DEFINE for sys32_quotactl()

While sys32_quotactl() is only needed on x86, it can use the recommended
COMPAT_SYSCALL_DEFINEx() machinery for its setup.
Acked-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

arch/x86/entry/syscalls/syscall_32.tbl

@@ -137,7 +137,7 @@
 128	i386	init_module		sys_init_module
 129	i386	delete_module		sys_delete_module
 130	i386	get_kernel_syms
-131	i386	quotactl		sys_quotactl			sys32_quotactl
+131	i386	quotactl		sys_quotactl			compat_sys_quotactl32
 132	i386	getpgid			sys_getpgid
 133	i386	fchdir			sys_fchdir
 134	i386	bdflush			sys_bdflush

fs/quota/compat.c

@@ -41,8 +41,9 @@ struct compat_fs_quota_stat {
 	__u16		qs_iwarnlimit;
 };
 
-asmlinkage long sys32_quotactl(unsigned int cmd, const char __user *special,
-						qid_t id, void __user *addr)
+COMPAT_SYSCALL_DEFINE4(quotactl32, unsigned int, cmd,
+		       const char __user *, special, qid_t, id,
+		       void __user *, addr)
 {
 	unsigned int cmds;
 	struct if_dqblk __user *dqblk;

include/linux/compat.h

@@ -461,6 +461,9 @@ asmlinkage ssize_t compat_sys_pwritev2(compat_ulong_t fd,
 		const struct compat_iovec __user *vec,
 		compat_ulong_t vlen, u32 pos_low, u32 pos_high, rwf_t flags);
 
+asmlinkage long compat_sys_quotactl32(unsigned int cmd,
+		const char __user *special, qid_t id, void __user *addr);
+
 #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64
 asmlinkage long compat_sys_preadv64(unsigned long fd,
 		const struct compat_iovec __user *vec,

include/linux/syscalls.h

@@ -241,8 +241,6 @@ static inline void addr_limit_user_check(void)
 #endif
 }
 
-asmlinkage long sys32_quotactl(unsigned int cmd, const char __user *special,
-			       qid_t id, void __user *addr);
 asmlinkage long sys_time(time_t __user *tloc);
 asmlinkage long sys_stime(time_t __user *tptr);
 asmlinkage long sys_gettimeofday(struct timeval __user *tv,

kernel/sys_ni.c

@@ -18,7 +18,7 @@ asmlinkage long sys_ni_syscall(void)
 }
 
 cond_syscall(sys_quotactl);
-cond_syscall(sys32_quotactl);
+cond_syscall(compat_sys_quotactl32);
 cond_syscall(sys_acct);
 cond_syscall(sys_lookup_dcookie);
 cond_syscall(compat_sys_lookup_dcookie);