cleanup may_open

Add a switch for the various i_mode fmt cases, and remove the comment
about writeability of devices nodes - that part is handled in
inode_permission and comment on (briefly) there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Christoph Hellwig 2009-01-05 19:27:23 +01:00 committed by Al Viro
parent b6520c8193
commit c8fe8f30c7

View file

@ -1486,24 +1486,22 @@ int may_open(struct path *path, int acc_mode, int flag)
if (!inode)
return -ENOENT;
if (S_ISLNK(inode->i_mode))
switch (inode->i_mode & S_IFMT) {
case S_IFLNK:
return -ELOOP;
if (S_ISDIR(inode->i_mode) && (acc_mode & MAY_WRITE))
return -EISDIR;
/*
* FIFO's, sockets and device files are special: they don't
* actually live on the filesystem itself, and as such you
* can write to them even if the filesystem is read-only.
*/
if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
flag &= ~O_TRUNC;
} else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
case S_IFDIR:
if (acc_mode & MAY_WRITE)
return -EISDIR;
break;
case S_IFBLK:
case S_IFCHR:
if (path->mnt->mnt_flags & MNT_NODEV)
return -EACCES;
/*FALLTHRU*/
case S_IFIFO:
case S_IFSOCK:
flag &= ~O_TRUNC;
break;
}
error = inode_permission(inode, acc_mode);