/* Reopen the same filesystem object as an exsiting filp.
* Result is a distinct filp, with potentially different f_flags and f_mode.
*/
struct file *
cr_filp_reopen(const struct file *orig_filp, int new_flags)
{
return orig_filp ? cr_dentry_open(dget(orig_filp->f_dentry),
mntget(orig_filp->f_vfsmnt),
new_flags)
: ERR_PTR(-EBADF);
}
/* Call both cr_permision() and cr_dentry_open().
*/
struct file *
cr_dentry_open_perm(struct path *path, int flags)
{
struct file *filp;
int acc_mask = ("\004\002\006\006"[flags&O_ACCMODE]); /* ACC_MODE(open_to_namei_flags()) */
int err;
err = cr_permission(path->dentry->d_inode, acc_mask);
filp = ERR_PTR(err);
if (!IS_ERR(filp)) {
filp = cr_dentry_open(path, flags);
}
return filp;
}
/* Calls cr_mknod and then opens with the given flags, returning a (struct file *) */
struct file *
cr_filp_mknod(cr_errbuf_t *eb, const char *name, int mode, int flags, unsigned long unlinked_id) {
struct nameidata nd;
struct dentry * dentry;
struct file *filp;
/* mknod */
dentry = cr_mknod(eb, &nd, name, mode, unlinked_id);
if (IS_ERR(dentry)) {
CR_KTRACE_UNEXPECTED("Failed to recreate %sfilesystem object %s, err=%d.",
unlinked_id?"unlinked ":"", name, (int)PTR_ERR(dentry));
filp = (struct file *)dentry;
goto out;
}
/* now open it */
filp = cr_dentry_open(dget(dentry), mntget(nd.nd_mnt), flags);
if (IS_ERR(filp)) {
CR_ERR_EB(eb, "Failed to reopen %sfilesystem object %s, err=%d.",
unlinked_id?"unlinked ":"", name, (int)PTR_ERR(dentry));
goto out_dput;
}
/* check that we actually got the expected type */
if ((mode ^ filp->f_dentry->d_inode->i_mode) & S_IFMT) {
CR_ERR_EB(eb, "Type conflict when recreating %sfilesystem object %s.",
unlinked_id?"unlinked ":"", name);
fput(filp);
filp = ERR_PTR(-EEXIST);
goto out_dput;
}
out_dput:
dput(dentry);
cr_path_release(&nd);
out:
return filp;
}
