linux-zen-desktop/arch/s390/net/bpf_jit.h

56 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* BPF Jit compiler defines
*
* Copyright IBM Corp. 2012,2015
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
* Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
#ifndef __ARCH_S390_NET_BPF_JIT_H
#define __ARCH_S390_NET_BPF_JIT_H
#ifndef __ASSEMBLY__
#include <linux/filter.h>
#include <linux/types.h>
#endif /* __ASSEMBLY__ */
/*
* Stackframe layout (packed stack):
*
* ^ high
* +---------------+ |
* | old backchain | |
* +---------------+ |
* | r15 - r6 | |
* +---------------+ |
* | 4 byte align | |
* | tail_call_cnt | |
* BFP -> +===============+ |
* | | |
* | BPF stack | |
* | | |
* R15+160 -> +---------------+ |
* | new backchain | |
* R15+152 -> +---------------+ |
* | + 152 byte SA | |
* R15 -> +---------------+ + low
*
* We get 160 bytes stack space from calling function, but only use
* 12 * 8 byte for old backchain, r15..r6, and tail_call_cnt.
*
* The stack size used by the BPF program ("BPF stack" above) is passed
* via "aux->stack_depth".
*/
#define STK_SPACE_ADD (160)
#define STK_160_UNUSED (160 - 12 * 8)
#define STK_OFF (STK_SPACE_ADD - STK_160_UNUSED)
#define STK_OFF_R6 (160 - 11 * 8) /* Offset of r6 on stack */
#define STK_OFF_TCCNT (160 - 12 * 8) /* Offset of tail_call_cnt on stack */
#endif /* __ARCH_S390_NET_BPF_JIT_H */