/** * write_unlock_fs - Release all locks on a local file system * * Experimental. * * Input: * buf: '\n'-terminated C string containing the * absolute pathname of a local file system * size: length of C string in @buf * Output: * On success: returns zero if all specified locks were released; * returns one if one or more locks were not released * On error: return code is negative errno value */ static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size) { struct path path; char *fo_path; int error; /* sanity check */ if (size == 0) return -EINVAL; if (buf[size-1] != '\n') return -EINVAL; fo_path = buf; if (qword_get(&buf, fo_path, size) < 0) return -EINVAL; error = kern_path(fo_path, 0, &path); if (error) return error; /* * XXX: Needs better sanity checking. Otherwise we could end up * releasing locks on the wrong file system. * * For example: * 1. Does the path refer to a directory? * 2. Is that directory a mount point, or * 3. Is that directory the root of an exported file system? */ error = nlmsvc_unlock_all_by_sb(path.mnt->mnt_sb); path_put(&path); return error; }
static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size) { struct path path; char *fo_path; int error; if (size == 0) return -EINVAL; if (buf[size-1] != '\n') return -EINVAL; fo_path = buf; if (qword_get(&buf, fo_path, size) < 0) return -EINVAL; error = kern_path(fo_path, 0, &path); if (error) return error; error = nlmsvc_unlock_all_by_sb(path.dentry->d_sb); path_put(&path); return error; }