... it does nothing if nd->last_type is LAST_BIND.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

If we get ERR_PTR() from get_link(), we are guaranteed to get err != 0
when we break out of do-while, so we are going to hit if (err) return err;
shortly after it.  Pull that into the if (IS_ERR(s)) body.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

All remaining callers of the former are preceded by the latter
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and strip __always_inline from follow_link() - remaining callers
don't need that.

Now link_path_walk() recursion is a direct one.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We used to need it to feed to follow_link().  No more...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

shares space with nameidata->next, walk_component() et.al. store
the struct path of symlink instead of returning it into a variable
passed by caller.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

with new calling conventions it's trivial
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Conflicts:
	fs/namei.c

Split a piece of fs/namei.c:follow_link() that does obtaining the link
body into a separate function.  follow_link() itself is converted to
calling get_link() and then doing the body traversal (if any).

The next step will expand follow_link() call in link_path_walk()
and this helps to keep the size down...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body.  Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks.  Stored pointer
is ignored in all cases except the last one.

Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().

b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is.  In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

when we go for on-demand allocation of saved state in
link_path_walk(), we'll want nameidata to stay around
for all 3 calls of path_mountpoint().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

that avoids having nameidata on stack during the calls of
->rmdir()/->unlink() and *two* of those during the calls
of ->rename().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

it's a convenient helper, but we'll want to shift nameidata
down the call chain, so it won't be available there...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

With LOOKUP_FOLLOW we unlazy and return 1; without it we either
fail with ELOOP or, for O_PATH opens, succeed.  No need to mix
those cases...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

When O_PATH is present, O_CREAT isn't, so symlink_ok is always equal to
(open_flags & O_PATH) && !(nd->flags & LOOKUP_FOLLOW).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

seriously improves the stack *and* I-cache footprint...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

No ->inode_follow_link() methods use the nameidata arg, and
it is about to become private to namei.c.
So remove from all inode_follow_link() functions.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

ACK-by: NBoaz Harrosh <ooo@electrozaur.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Reviewed-by: NJan Kara <jack@suse.cz>
Acked-by: NDave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

for fast symlinks only, of course...
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

let "fast" symlinks store the pointer to the body into ->i_link and
use simple_follow_link for ->follow_link()
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

ovl_follow_link current calls ->put_link on an error path.
However ->put_link is about to change in a way that it will be
impossible to call it from ovl_follow_link.

So rearrange the code to avoid the need for that error path.
Specifically: move the kmalloc() call before the ->follow_link()
call to the subordinate filesystem.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We copy there a kmalloc'ed string and proceed to kfree that string immediately
after that.  Easier to just feed that string to nd_set_link() and _not_
kfree it until ->put_link() (which becomes kfree_put_link() in that case).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>