Ejemplo n.º 1
0
/* common function to regular file and dir */
int au_reval_and_lock_fdi(struct file *file, int (*reopen)(struct file *file),
			  int wlock)
{
	int err;
	unsigned int sigen, figen;
	aufs_bindex_t bstart;
	unsigned char pseudo_link;
	struct dentry *dentry;
	struct inode *inode;

	err = 0;
	dentry = file->f_dentry;
	inode = dentry->d_inode;
	AuDebugOn(au_special_file(inode->i_mode));
	sigen = au_sigen(dentry->d_sb);
	fi_write_lock(file);
	figen = au_figen(file);
	di_write_lock_child(dentry);
	bstart = au_dbstart(dentry);
	pseudo_link = (bstart != au_ibstart(inode));
	if (sigen == figen && !pseudo_link && au_fbstart(file) == bstart) {
		if (!wlock) {
			di_downgrade_lock(dentry, AuLock_IR);
			fi_downgrade_lock(file);
		}
		goto out; /* success */
	}

	AuDbg("sigen %d, figen %d\n", sigen, figen);
	if (sigen != au_digen(dentry)
	    || sigen != au_iigen(inode)) {
		err = au_reval_dpath(dentry, sigen);
		if (unlikely(err < 0))
			goto out;
		AuDebugOn(au_digen(dentry) != sigen
			  || au_iigen(inode) != sigen);
	}

	err = refresh_file(file, reopen);
	if (!err) {
		if (!wlock) {
			di_downgrade_lock(dentry, AuLock_IR);
			fi_downgrade_lock(file);
		}
	} else {
		di_write_unlock(dentry);
		fi_write_unlock(file);
	}

out:
	return err;
}
Ejemplo n.º 2
0
static int do_pri_file(aufs_bindex_t bindex, struct file *file)
{
	char a[32];

	if (!file || IS_ERR(file)) {
		dpri("f%d: err %ld\n", bindex, PTR_ERR(file));
		return -1;
	}
	a[0] = 0;
	if (bindex < 0
	    && file->f_dentry
	    && au_test_aufs(file->f_dentry->d_sb)
	    && au_fi(file))
		snprintf(a, sizeof(a), ", gen %d, mmapped %d",
			 au_figen(file), atomic_read(&au_fi(file)->fi_mmapped));
	dpri("f%d: mode 0x%x, flags 0%o, cnt %ld, v %llu, pos %llu%s\n",
	     bindex, file->f_mode, file->f_flags, (long)file_count(file),
	     file->f_version, file->f_pos, a);
	if (file->f_dentry)
		do_pri_dentry(bindex, file->f_dentry);
	return 0;
}
Ejemplo n.º 3
0
static int au_rdu(struct file *file, struct aufs_rdu *rdu)
{
	int err;
	aufs_bindex_t bend;
	struct au_rdu_arg arg;
	struct dentry *dentry;
	struct inode *inode;
	struct file *h_file;
	struct au_rdu_cookie *cookie = &rdu->cookie;

	err = !access_ok(VERIFY_WRITE, rdu->ent.e, rdu->sz);
	if (unlikely(err)) {
		err = -EFAULT;
		AuTraceErr(err);
		goto out;
	}
	rdu->rent = 0;
	rdu->tail = rdu->ent;
	rdu->full = 0;
	arg.rdu = rdu;
	arg.ent = rdu->ent;
	arg.end = arg.ent.ul;
	arg.end += rdu->sz;

	err = -ENOTDIR;
	if (unlikely(!file->f_op || !file->f_op->readdir))
		goto out;

	err = security_file_permission(file, MAY_READ);
	AuTraceErr(err);
	if (unlikely(err))
		goto out;

	dentry = file->f_dentry;
	inode = dentry->d_inode;
#if 1
	mutex_lock(&inode->i_mutex);
#else
	err = mutex_lock_killable(&inode->i_mutex);
	AuTraceErr(err);
	if (unlikely(err))
		goto out;
#endif
	err = -ENOENT;
	if (unlikely(IS_DEADDIR(inode)))
		goto out_mtx;

	arg.sb = inode->i_sb;
	si_read_lock(arg.sb, AuLock_FLUSH);
	fi_read_lock(file);

	err = -EAGAIN;
	if (unlikely(au_ftest_rdu(cookie->flags, CONT)
		     && cookie->generation != au_figen(file)))
		goto out_unlock;

	err = 0;
	if (!rdu->blk) {
		rdu->blk = au_sbi(arg.sb)->si_rdblk;
		if (!rdu->blk)
			rdu->blk = au_dir_size(file, /*dentry*/NULL);
	}
	bend = au_fbstart(file);
	if (cookie->bindex < bend)
		cookie->bindex = bend;
	bend = au_fbend_dir(file);
	/* AuDbg("b%d, b%d\n", cookie->bindex, bend); */
	for (; !err && cookie->bindex <= bend;
	     cookie->bindex++, cookie->h_pos = 0) {
		h_file = au_hf_dir(file, cookie->bindex);
		if (!h_file)
			continue;

		au_fclr_rdu(cookie->flags, FULL);
		err = au_rdu_do(h_file, &arg);
		AuTraceErr(err);
		if (unlikely(au_ftest_rdu(cookie->flags, FULL) || err))
			break;
	}
	AuDbg("rent %llu\n", rdu->rent);

	if (!err && !au_ftest_rdu(cookie->flags, CONT)) {
		rdu->shwh = !!au_opt_test(au_sbi(arg.sb)->si_mntflags, SHWH);
		au_fset_rdu(cookie->flags, CONT);
		cookie->generation = au_figen(file);
	}

	ii_read_lock_child(inode);
	fsstack_copy_attr_atime(inode, au_h_iptr(inode, au_ibstart(inode)));
	ii_read_unlock(inode);

 out_unlock:
	fi_read_unlock(file);
	si_read_unlock(arg.sb);
 out_mtx:
	mutex_unlock(&inode->i_mutex);
 out:
	AuTraceErr(err);
	return err;
}