Commit 63b6df14 authored by Al Viro's avatar Al Viro
Browse files

give readdir(2)/getdents(2)/etc. uniform exclusion with lseek() 



same as read() on regular files has, and for the same reason.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 9902af79

arch/alpha/kernel/osf_sys.c

+2 −2
Original line number Diff line number Diff line
@@ -147,7 +147,7 @@ SYSCALL_DEFINE4(osf_getdirentries, unsigned int, fd, 
		long __user *, basep)

{

	int error;

	struct fd arg = fdget(fd);

	struct fd arg = fdget_pos(fd);

	struct osf_dirent_callback buf = {

		.ctx.actor = osf_filldir,

		.dirent = dirent,
@@ -164,7 +164,7 @@ SYSCALL_DEFINE4(osf_getdirentries, unsigned int, fd, 
	if (count != buf.count)

		error = count - buf.count;



	fdput(arg);

	fdput_pos(arg);

	return error;

}

fs/compat.c

+6 −6
Original line number Diff line number Diff line
@@ -884,7 +884,7 @@ COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd, 
		struct compat_old_linux_dirent __user *, dirent, unsigned int, count)

{

	int error;

	struct fd f = fdget(fd);

	struct fd f = fdget_pos(fd);

	struct compat_readdir_callback buf = {

		.ctx.actor = compat_fillonedir,

		.dirent = dirent
@@ -897,7 +897,7 @@ COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd, 
	if (buf.result)

		error = buf.result;



	fdput(f);

	fdput_pos(f);

	return error;

}
@@ -975,7 +975,7 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, 
	if (!access_ok(VERIFY_WRITE, dirent, count))

		return -EFAULT;



	f = fdget(fd);

	f = fdget_pos(fd);

	if (!f.file)

		return -EBADF;
@@ -989,7 +989,7 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, 
		else

			error = count - buf.count;

	}

	fdput(f);

	fdput_pos(f);

	return error;

}
@@ -1062,7 +1062,7 @@ COMPAT_SYSCALL_DEFINE3(getdents64, unsigned int, fd, 
	if (!access_ok(VERIFY_WRITE, dirent, count))

		return -EFAULT;



	f = fdget(fd);

	f = fdget_pos(fd);

	if (!f.file)

		return -EBADF;
@@ -1077,7 +1077,7 @@ COMPAT_SYSCALL_DEFINE3(getdents64, unsigned int, fd, 
		else

			error = count - buf.count;

	}

	fdput(f);

	fdput_pos(f);

	return error;

}

#endif /* __ARCH_WANT_COMPAT_SYS_GETDENTS64 */

fs/file.c

+5 −0
Original line number Diff line number Diff line
@@ -784,6 +784,11 @@ unsigned long __fdget_pos(unsigned int fd) 
	return v;

}



void __f_unlock_pos(struct file *f)

{

	mutex_unlock(&f->f_pos_lock);

}



/*

 * We only lock f_pos if we have threads or if the file might be

 * shared with another process. In both cases we'll have an elevated

fs/open.c

+1 −1
Original line number Diff line number Diff line
@@ -713,7 +713,7 @@ static int do_dentry_open(struct file *f, 
	}



	/* POSIX.1-2008/SUSv4 Section XSI 2.9.7 */

	if (S_ISREG(inode->i_mode))

	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))

		f->f_mode |= FMODE_ATOMIC_POS;



	f->f_op = fops_get(inode->i_fop);

fs/read_write.c

+0 −12
Original line number Diff line number Diff line
@@ -302,18 +302,6 @@ loff_t vfs_llseek(struct file *file, loff_t offset, int whence) 
}

EXPORT_SYMBOL(vfs_llseek);



static inline struct fd fdget_pos(int fd)

{

	return __to_fd(__fdget_pos(fd));

}



static inline void fdput_pos(struct fd f)

{

	if (f.flags & FDPUT_POS_UNLOCK)

		mutex_unlock(&f.file->f_pos_lock);

	fdput(f);

}



SYSCALL_DEFINE3(lseek, unsigned int, fd, off_t, offset, unsigned int, whence)

{

	off_t retval;