namei: move saved_nd pointer into struct nameidata

these guys are always declared next to each other; might as well put
the former (pointer to previous instance) into the latter and simplify
the calling conventions for {set,restore}_nameidata()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2015-05-13 07:28:08 -04:00
parent 520ae68747
commit 9883d1855e

View File

@ -498,10 +498,8 @@ struct nameidata {
struct qstr last;
struct path root;
struct inode *inode; /* path.dentry.d_inode */
struct filename *name;
int dfd;
unsigned int flags;
unsigned seq, m_seq, root_seq;
unsigned seq, m_seq;
int last_type;
unsigned depth;
int total_link_count;
@ -512,23 +510,26 @@ struct nameidata {
struct inode *inode;
unsigned seq;
} *stack, internal[EMBEDDED_LEVELS];
struct filename *name;
struct nameidata *saved;
unsigned root_seq;
int dfd;
};
static struct nameidata *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;
p->dfd = dfd;
p->name = name;
p->total_link_count = old ? old->total_link_count : 0;
p->saved = old;
current->nameidata = p;
return old;
}
static void restore_nameidata(struct nameidata *old)
static void restore_nameidata(void)
{
struct nameidata *now = current->nameidata;
struct nameidata *now = current->nameidata, *old = now->saved;
current->nameidata = old;
if (old)
@ -2120,14 +2121,14 @@ static int filename_lookup(int dfd, struct filename *name, unsigned flags,
struct path *path, struct path *root)
{
int retval;
struct nameidata nd, *saved_nd;
struct nameidata nd;
if (IS_ERR(name))
return PTR_ERR(name);
saved_nd = set_nameidata(&nd, dfd, name);
if (unlikely(root)) {
nd.root = *root;
flags |= LOOKUP_ROOT;
}
set_nameidata(&nd, dfd, name);
retval = path_lookupat(&nd, flags | LOOKUP_RCU, path);
if (unlikely(retval == -ECHILD))
retval = path_lookupat(&nd, flags, path);
@ -2136,7 +2137,7 @@ static int filename_lookup(int dfd, struct filename *name, unsigned flags,
if (likely(!retval))
audit_inode(name, path->dentry, flags & LOOKUP_PARENT);
restore_nameidata(saved_nd);
restore_nameidata();
putname(name);
return retval;
}
@ -2166,11 +2167,11 @@ static struct filename *filename_parentat(int dfd, struct filename *name,
struct qstr *last, int *type)
{
int retval;
struct nameidata nd, *saved_nd;
struct nameidata nd;
if (IS_ERR(name))
return name;
saved_nd = set_nameidata(&nd, dfd, name);
set_nameidata(&nd, dfd, name);
retval = path_parentat(&nd, flags | LOOKUP_RCU, parent);
if (unlikely(retval == -ECHILD))
retval = path_parentat(&nd, flags, parent);
@ -2184,7 +2185,7 @@ static struct filename *filename_parentat(int dfd, struct filename *name,
putname(name);
name = ERR_PTR(retval);
}
restore_nameidata(saved_nd);
restore_nameidata();
return name;
}
@ -2445,11 +2446,11 @@ static int
filename_mountpoint(int dfd, struct filename *name, struct path *path,
unsigned int flags)
{
struct nameidata nd, *saved;
struct nameidata nd;
int error;
if (IS_ERR(name))
return PTR_ERR(name);
saved = set_nameidata(&nd, dfd, name);
set_nameidata(&nd, dfd, name);
error = path_mountpoint(&nd, flags | LOOKUP_RCU, path);
if (unlikely(error == -ECHILD))
error = path_mountpoint(&nd, flags, path);
@ -2457,7 +2458,7 @@ filename_mountpoint(int dfd, struct filename *name, struct path *path,
error = path_mountpoint(&nd, flags | LOOKUP_REVAL, path);
if (likely(!error))
audit_inode(name, path->dentry, 0);
restore_nameidata(saved);
restore_nameidata();
putname(name);
return error;
}
@ -3327,23 +3328,24 @@ static struct file *path_openat(struct nameidata *nd,
struct file *do_filp_open(int dfd, struct filename *pathname,
const struct open_flags *op)
{
struct nameidata nd, *saved_nd = set_nameidata(&nd, dfd, pathname);
struct nameidata nd;
int flags = op->lookup_flags;
struct file *filp;
set_nameidata(&nd, dfd, pathname);
filp = path_openat(&nd, op, flags | LOOKUP_RCU);
if (unlikely(filp == ERR_PTR(-ECHILD)))
filp = path_openat(&nd, op, flags);
if (unlikely(filp == ERR_PTR(-ESTALE)))
filp = path_openat(&nd, op, flags | LOOKUP_REVAL);
restore_nameidata(saved_nd);
restore_nameidata();
return filp;
}
struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt,
const char *name, const struct open_flags *op)
{
struct nameidata nd, *saved_nd;
struct nameidata nd;
struct file *file;
struct filename *filename;
int flags = op->lookup_flags | LOOKUP_ROOT;
@ -3358,13 +3360,13 @@ struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt,
if (unlikely(IS_ERR(filename)))
return ERR_CAST(filename);
saved_nd = set_nameidata(&nd, -1, filename);
set_nameidata(&nd, -1, filename);
file = path_openat(&nd, op, flags | LOOKUP_RCU);
if (unlikely(file == ERR_PTR(-ECHILD)))
file = path_openat(&nd, op, flags);
if (unlikely(file == ERR_PTR(-ESTALE)))
file = path_openat(&nd, op, flags | LOOKUP_REVAL);
restore_nameidata(saved_nd);
restore_nameidata();
putname(filename);
return file;
}