1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * BPF Jit compiler defines
4 *
5 * Copyright IBM Corp. 2012,2015
6 *
7 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
8 *	      Michael Holzheu <holzheu@linux.vnet.ibm.com>
9 */
10
11#ifndef __ARCH_S390_NET_BPF_JIT_H
12#define __ARCH_S390_NET_BPF_JIT_H
13
14#ifndef __ASSEMBLY__
15
16#include <linux/filter.h>
17#include <linux/types.h>
18
19#endif /* __ASSEMBLY__ */
20
21/*
22 * Stackframe layout (packed stack):
23 *
24 *				    ^ high
25 *	      +---------------+     |
26 *	      | old backchain |     |
27 *	      +---------------+     |
28 *	      |   r15 - r6    |     |
29 *	      +---------------+     |
30 *	      | 4 byte align  |     |
31 *	      | tail_call_cnt |     |
32 * BFP	   -> +===============+     |
33 *	      |		      |     |
34 *	      |   BPF stack   |     |
35 *	      |		      |     |
36 * R15+160 -> +---------------+     |
37 *	      | new backchain |     |
38 * R15+152 -> +---------------+     |
39 *	      | + 152 byte SA |     |
40 * R15	   -> +---------------+     + low
41 *
42 * We get 160 bytes stack space from calling function, but only use
43 * 12 * 8 byte for old backchain, r15..r6, and tail_call_cnt.
44 *
45 * The stack size used by the BPF program ("BPF stack" above) is passed
46 * via "aux->stack_depth".
47 */
48#define STK_SPACE_ADD	(160)
49#define STK_160_UNUSED	(160 - 12 * 8)
50#define STK_OFF		(STK_SPACE_ADD - STK_160_UNUSED)
51
52#define STK_OFF_R6	(160 - 11 * 8)	/* Offset of r6 on stack */
53#define STK_OFF_TCCNT	(160 - 12 * 8)	/* Offset of tail_call_cnt on stack */
54
55#endif /* __ARCH_S390_NET_BPF_JIT_H */
56