namei: move link/cookie pairs into nameidata

Array of MAX_NESTED_LINKS + 1 elements put into nameidata;
what used to be a local array in link_path_walk() occupies
entries 1 .. MAX_NESTED_LINKS in it, link and cookie from
the trailing symlink handling loops - entry 0.

This is _not_ the final arrangement; just an easily verified
incremental step.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2015-05-02 19:38:35 -04:00
parent 9e18f10a30
commit 697fc6ca66
1 changed files with 18 additions and 17 deletions

View File

@ -505,6 +505,11 @@ struct nameidata {
int last_type;
unsigned depth;
struct file *base;
struct saved {
struct path link;
void *cookie;
const char *name;
} stack[MAX_NESTED_LINKS + 1];
};
/*
@ -1711,11 +1716,7 @@ static inline u64 hash_name(const char *name)
*/
static int link_path_walk(const char *name, struct nameidata *nd)
{
struct saved {
struct path link;
void *cookie;
const char *name;
} stack[MAX_NESTED_LINKS], *last = stack + nd->depth - 1;
struct saved *last = nd->stack;
int err;
while (*name=='/')
@ -2030,13 +2031,13 @@ static int path_lookupat(int dfd, const struct filename *name,
if (!err && !(flags & LOOKUP_PARENT)) {
err = lookup_last(nd);
while (err > 0) {
void *cookie;
struct path link = nd->link;
err = trailing_symlink(&link, nd, &cookie);
nd->stack[0].link = nd->link;
err = trailing_symlink(&nd->stack[0].link,
nd, &nd->stack[0].cookie);
if (err)
break;
err = lookup_last(nd);
put_link(nd, &link, cookie);
put_link(nd, &nd->stack[0].link, nd->stack[0].cookie);
}
}
@ -2376,13 +2377,13 @@ path_mountpoint(int dfd, const struct filename *name, struct path *path,
err = mountpoint_last(nd, path);
while (err > 0) {
void *cookie;
struct path link = *path;
err = trailing_symlink(&link, nd, &cookie);
nd->stack[0].link = nd->link;
err = trailing_symlink(&nd->stack[0].link,
nd, &nd->stack[0].cookie);
if (err)
break;
err = mountpoint_last(nd, path);
put_link(nd, &link, cookie);
put_link(nd, &nd->stack[0].link, nd->stack[0].cookie);
}
out:
path_cleanup(nd);
@ -3259,14 +3260,14 @@ static struct file *path_openat(int dfd, struct filename *pathname,
error = do_last(nd, file, op, &opened, pathname);
while (unlikely(error > 0)) { /* trailing symlink */
struct path link = nd->link;
void *cookie;
nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
error = trailing_symlink(&link, nd, &cookie);
nd->stack[0].link = nd->link;
error= trailing_symlink(&nd->stack[0].link,
nd, &nd->stack[0].cookie);
if (unlikely(error))
break;
error = do_last(nd, file, op, &opened, pathname);
put_link(nd, &link, cookie);
put_link(nd, &nd->stack[0].link, nd->stack[0].cookie);
}
out:
path_cleanup(nd);