mqueue: move compat syscalls to native ones

... and stop messing with compat_alloc_user_space() and friends

[braino fix from Colin King folded in]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ipc/Makefile

@@ -5,8 +5,7 @@
 obj-$(CONFIG_SYSVIPC_COMPAT) += compat.o
 obj-$(CONFIG_SYSVIPC) += util.o msgutil.o msg.o sem.o shm.o syscall.o
 obj-$(CONFIG_SYSVIPC_SYSCTL) += ipc_sysctl.o
-obj_mq-$(CONFIG_COMPAT) += compat_mq.o
-obj-$(CONFIG_POSIX_MQUEUE) += mqueue.o msgutil.o $(obj_mq-y)
+obj-$(CONFIG_POSIX_MQUEUE) += mqueue.o msgutil.o
 obj-$(CONFIG_IPC_NS) += namespace.o
 obj-$(CONFIG_POSIX_MQUEUE_SYSCTL) += mq_sysctl.o
 

ipc/compat_mq.c

-/*
- *  ipc/compat_mq.c
- *    32 bit emulation for POSIX message queue system calls
- *
- *    Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
- *    Author: Arnd Bergmann <arnd@arndb.de>
- */
-
-#include <linux/compat.h>
-#include <linux/fs.h>
-#include <linux/kernel.h>
-#include <linux/mqueue.h>
-#include <linux/syscalls.h>
-
-#include <linux/uaccess.h>
-
-struct compat_mq_attr {
-	compat_long_t mq_flags;      /* message queue flags		     */
-	compat_long_t mq_maxmsg;     /* maximum number of messages	     */
-	compat_long_t mq_msgsize;    /* maximum message size		     */
-	compat_long_t mq_curmsgs;    /* number of messages currently queued  */
-	compat_long_t __reserved[4]; /* ignored for input, zeroed for output */
-};
-
-static inline int get_compat_mq_attr(struct mq_attr *attr,
-			const struct compat_mq_attr __user *uattr)
-{
-	if (!access_ok(VERIFY_READ, uattr, sizeof *uattr))
-		return -EFAULT;
-
-	return __get_user(attr->mq_flags, &uattr->mq_flags)
-		| __get_user(attr->mq_maxmsg, &uattr->mq_maxmsg)
-		| __get_user(attr->mq_msgsize, &uattr->mq_msgsize)
-		| __get_user(attr->mq_curmsgs, &uattr->mq_curmsgs);
-}
-
-static inline int put_compat_mq_attr(const struct mq_attr *attr,
-			struct compat_mq_attr __user *uattr)
-{
-	if (clear_user(uattr, sizeof *uattr))
-		return -EFAULT;
-
-	return __put_user(attr->mq_flags, &uattr->mq_flags)
-		| __put_user(attr->mq_maxmsg, &uattr->mq_maxmsg)
-		| __put_user(attr->mq_msgsize, &uattr->mq_msgsize)
-		| __put_user(attr->mq_curmsgs, &uattr->mq_curmsgs);
-}
-
-COMPAT_SYSCALL_DEFINE4(mq_open, const char __user *, u_name,
-		       int, oflag, compat_mode_t, mode,
-		       struct compat_mq_attr __user *, u_attr)
-{
-	void __user *p = NULL;
-	if (u_attr && oflag & O_CREAT) {
-		struct mq_attr attr;
-
-		memset(&attr, 0, sizeof(attr));
-
-		p = compat_alloc_user_space(sizeof(attr));
-		if (get_compat_mq_attr(&attr, u_attr) ||
-		    copy_to_user(p, &attr, sizeof(attr)))
-			return -EFAULT;
-	}
-	return sys_mq_open(u_name, oflag, mode, p);
-}
-
-COMPAT_SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes,
-		       const char __user *, u_msg_ptr,
-		       compat_size_t, msg_len, unsigned int, msg_prio,
-		       const struct compat_timespec __user *, u_abs_timeout)
-{
-	struct timespec __user *u_ts;
-
-	if (compat_convert_timespec(&u_ts, u_abs_timeout))
-		return -EFAULT;
-
-	return sys_mq_timedsend(mqdes, u_msg_ptr, msg_len,
-			msg_prio, u_ts);
-}
-
-COMPAT_SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes,
-		       char __user *, u_msg_ptr,
-		       compat_size_t, msg_len, unsigned int __user *, u_msg_prio,
-		       const struct compat_timespec __user *, u_abs_timeout)
-{
-	struct timespec __user *u_ts;
-
-	if (compat_convert_timespec(&u_ts, u_abs_timeout))
-		return -EFAULT;
-
-	return sys_mq_timedreceive(mqdes, u_msg_ptr, msg_len,
-			u_msg_prio, u_ts);
-}
-
-COMPAT_SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes,
-		       const struct compat_sigevent __user *, u_notification)
-{
-	struct sigevent __user *p = NULL;
-	if (u_notification) {
-		struct sigevent n;
-		p = compat_alloc_user_space(sizeof(*p));
-		if (get_compat_sigevent(&n, u_notification))
-			return -EFAULT;
-		if (n.sigev_notify == SIGEV_THREAD)
-			n.sigev_value.sival_ptr = compat_ptr(n.sigev_value.sival_int);
-		if (copy_to_user(p, &n, sizeof(*p)))
-			return -EFAULT;
-	}
-	return sys_mq_notify(mqdes, p);
-}
-
-COMPAT_SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
-		       const struct compat_mq_attr __user *, u_mqstat,
-		       struct compat_mq_attr __user *, u_omqstat)
-{
-	struct mq_attr mqstat;
-	struct mq_attr __user *p = compat_alloc_user_space(2 * sizeof(*p));
-	long ret;
-
-	memset(&mqstat, 0, sizeof(mqstat));
-
-	if (u_mqstat) {
-		if (get_compat_mq_attr(&mqstat, u_mqstat) ||
-		    copy_to_user(p, &mqstat, sizeof(mqstat)))
-			return -EFAULT;
-	}
-	ret = sys_mq_getsetattr(mqdes,
-				u_mqstat ? p : NULL,
-				u_omqstat ? p + 1 : NULL);
-	if (ret)
-		return ret;
-	if (u_omqstat) {
-		if (copy_from_user(&mqstat, p + 1, sizeof(mqstat)) ||
-		    put_compat_mq_attr(&mqstat, u_omqstat))
-			return -EFAULT;
-	}
-	return 0;
-}