[PATCH] fix mips sys32_p{read,write}

Switched to use of sys_pread64()/sys_pwrite64() rather than keep duplicating
their guts; among the little things that had been missing there were such as
ret = security_file_permission (file, MAY_READ);
Gotta love the LSM robustness, right?

Signed-off-by: Al Viro <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/mips/kernel/linux32.c

···
 asmlinkage ssize_t sys32_pread(unsigned int fd, char __user * buf,
 			       size_t count, u32 unused, u64 a4, u64 a5)
 {
-	ssize_t ret;
-	struct file * file;
-	ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
-	loff_t pos;
-
-	ret = -EBADF;
-	file = fget(fd);
-	if (!file)
-		goto bad_file;
-	if (!(file->f_mode & FMODE_READ))
-		goto out;
-	pos = merge_64(a4, a5);
-	ret = rw_verify_area(READ, file, &pos, count);
-	if (ret < 0)
-		goto out;
-	ret = -EINVAL;
-	if (!file->f_op || !(read = file->f_op->read))
-		goto out;
-	if (pos < 0)
-		goto out;
-	ret = -ESPIPE;
-	if (!(file->f_mode & FMODE_PREAD))
-		goto out;
-	ret = read(file, buf, count, &pos);
-	if (ret > 0)
-		dnotify_parent(file->f_dentry, DN_ACCESS);
-out:
-	fput(file);
-bad_file:
-	return ret;
+	return sys_pread64(fd, buf, count, merge_64(a4, a5));
 }
 
 asmlinkage ssize_t sys32_pwrite(unsigned int fd, const char __user * buf,
 			        size_t count, u32 unused, u64 a4, u64 a5)
 {
-	ssize_t ret;
-	struct file * file;
-	ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
-	loff_t pos;
-
-	ret = -EBADF;
-	file = fget(fd);
-	if (!file)
-		goto bad_file;
-	if (!(file->f_mode & FMODE_WRITE))
-		goto out;
-	pos = merge_64(a4, a5);
-	ret = rw_verify_area(WRITE, file, &pos, count);
-	if (ret < 0)
-		goto out;
-	ret = -EINVAL;
-	if (!file->f_op || !(write = file->f_op->write))
-		goto out;
-	if (pos < 0)
-		goto out;
-
-	ret = -ESPIPE;
-	if (!(file->f_mode & FMODE_PWRITE))
-		goto out;
-
-	ret = write(file, buf, count, &pos);
-	if (ret > 0)
-		dnotify_parent(file->f_dentry, DN_MODIFY);
-out:
-	fput(file);
-bad_file:
-	return ret;
+	return sys_pwrite64(fd, buf, count, merge_64(a4, a5));
 }
 
 asmlinkage int sys32_sched_rr_get_interval(compat_pid_t pid,