Commit 06422964 authored by Al Viro's avatar Al Viro
Browse files

teach set_nameidata() to handle setting the root as well 



That way we don't need the callers to mess with manually setting any fields
of nameidata instances.  Old set_nameidata() gets renamed (__set_nameidata()),
new becomes an inlined helper that takes a struct path pointer and deals
with setting nd->root and putting ND_ROOT_PRESET in nd->state when new
argument is non-NULL.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent bcba1e7d

fs/namei.c

+16 −12
Original line number Diff line number Diff line
@@ -577,7 +577,7 @@ struct nameidata { 
#define ND_ROOT_GRABBED 2

#define ND_JUMPED 4



static void set_nameidata(struct nameidata *p, int dfd, struct filename *name)

static void __set_nameidata(struct nameidata *p, int dfd, struct filename *name)

{

	struct nameidata *old = current->nameidata;

	p->stack = p->internal;
@@ -587,10 +587,20 @@ static void set_nameidata(struct nameidata *p, int dfd, struct filename *name) 
	p->path.dentry = NULL;

	p->total_link_count = old ? old->total_link_count : 0;

	p->saved = old;

	p->state = 0;

	current->nameidata = p;

}



static inline void set_nameidata(struct nameidata *p, int dfd, struct filename *name,

			  const struct path *root)

{

	__set_nameidata(p, dfd, name);

	p->state = 0;

	if (unlikely(root)) {

		p->state = ND_ROOT_PRESET;

		p->root = *root;

	}

}



static void restore_nameidata(void)

{

	struct nameidata *now = current->nameidata, *old = now->saved;
@@ -2454,11 +2464,7 @@ int filename_lookup(int dfd, struct filename *name, unsigned flags, 
	struct nameidata nd;

	if (IS_ERR(name))

		return PTR_ERR(name);

	set_nameidata(&nd, dfd, name);

	if (unlikely(root)) {

		nd.root = *root;

		nd.state = ND_ROOT_PRESET;

	}

	set_nameidata(&nd, dfd, name, root);

	retval = path_lookupat(&nd, flags | LOOKUP_RCU, path);

	if (unlikely(retval == -ECHILD))

		retval = path_lookupat(&nd, flags, path);
@@ -2499,7 +2505,7 @@ static struct filename *filename_parentat(int dfd, struct filename *name, 


	if (IS_ERR(name))

		return name;

	set_nameidata(&nd, dfd, name);

	set_nameidata(&nd, dfd, name, NULL);

	retval = path_parentat(&nd, flags | LOOKUP_RCU, parent);

	if (unlikely(retval == -ECHILD))

		retval = path_parentat(&nd, flags, parent);
@@ -3530,7 +3536,7 @@ struct file *do_filp_open(int dfd, struct filename *pathname, 
	int flags = op->lookup_flags;

	struct file *filp;



	set_nameidata(&nd, dfd, pathname);

	set_nameidata(&nd, dfd, pathname, NULL);

	filp = path_openat(&nd, op, flags | LOOKUP_RCU);

	if (unlikely(filp == ERR_PTR(-ECHILD)))

		filp = path_openat(&nd, op, flags);
@@ -3555,9 +3561,7 @@ struct file *do_file_open_root(const struct path *root, 
	if (IS_ERR(filename))

		return ERR_CAST(filename);



	set_nameidata(&nd, -1, filename);

	nd.root = *root;

	nd.state = ND_ROOT_PRESET;

	set_nameidata(&nd, -1, filename, root);

	file = path_openat(&nd, op, flags | LOOKUP_RCU);

	if (unlikely(file == ERR_PTR(-ECHILD)))

		file = path_openat(&nd, op, flags);