/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * Copyright (C) 2012 ARM Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #ifndef _UAPI__ASM_SIGCONTEXT_H #define _UAPI__ASM_SIGCONTEXT_H #ifndef __ASSEMBLY__ #include /* * Signal context structure - contains all info to do with the state * before the signal handler was invoked. */ struct sigcontext { __u64 fault_address; /* AArch64 registers */ __u64 regs[31]; __u64 sp; __u64 pc; __u64 pstate; /* 4K reserved for FP/SIMD state and future expansion */ __u8 __reserved[4096] __attribute__((__aligned__(16))); }; /* * Allocation of __reserved[]: * (Note: records do not necessarily occur in the order shown here.) * * size description * * 0x210 fpsimd_context * 0x10 esr_context * 0x8a0 sve_context (vl <= 64) (optional) * 0x20 extra_context (optional) * 0x10 terminator (null _aarch64_ctx) * * 0x510 (reserved for future allocation) * * New records that can exceed this space need to be opt-in for userspace, so * that an expanded signal frame is not generated unexpectedly. The mechanism * for opting in will depend on the extension that generates each new record. * The above table documents the maximum set and sizes of records than can be * generated when userspace does not opt in for any such extension. */ /* * Header to be used at the beginning of structures extending the user * context. Such structures must be placed after the rt_sigframe on the stack * and be 16-byte aligned. The last structure must be a dummy one with the * magic and size set to 0. */ struct _aarch64_ctx { __u32 magic; __u32 size; }; #define FPSIMD_MAGIC 0x46508001 struct fpsimd_context { struct _aarch64_ctx head; __u32 fpsr; __u32 fpcr; __uint128_t vregs[32]; }; /* * Note: similarly to all other integer fields, each V-register is stored in an * endianness-dependent format, with the byte at offset i from the start of the * in-memory representation of the register value containing * * bits [(7 + 8 * i) : (8 * i)] of the register on little-endian hosts; or * bits [(127 - 8 * i) : (120 - 8 * i)] on big-endian hosts. */ /* ESR_EL1 context */ #define ESR_MAGIC 0x45535201 struct esr_context { struct _aarch64_ctx head; __u64 esr; }; /* * extra_context: describes extra space in the signal frame for * additional structures that don't fit in sigcontext.__reserved[]. * * Note: * * 1) fpsimd_context, esr_context and extra_context must be placed in * sigcontext.__reserved[] if present. They cannot be placed in the * extra space. Any other record can be placed either in the extra * space or in sigcontext.__reserved[], unless otherwise specified in * this file. * * 2) There must not be more than one extra_context. * * 3) If extra_context is present, it must be followed immediately in * sigcontext.__reserved[] by the terminating null _aarch64_ctx. * * 4) The extra space to which datap points must start at the first * 16-byte aligned address immediately after the terminating null * _aarch64_ctx that follows the extra_context structure in * __reserved[]. The extra space may overrun the end of __reserved[], * as indicated by a sufficiently large value for the size field. * * 5) The extra space must itself be terminated with a null * _aarch64_ctx. */ #define EXTRA_MAGIC 0x45585401 struct extra_context { struct _aarch64_ctx head; __u64 datap; /* 16-byte aligned pointer to extra space cast to __u64 */ __u32 size; /* size in bytes of the extra space */ __u32 __reserved[3]; }; #define SVE_MAGIC 0x53564501 struct sve_context { struct _aarch64_ctx head; __u16 vl; __u16 __reserved[3]; }; #endif /* !__ASSEMBLY__ */ #include /* * The SVE architecture leaves space for future expansion of the * vector length beyond its initial architectural limit of 2048 bits * (16 quadwords). * * See linux/Documentation/arm64/sve.txt for a description of the VL/VQ * terminology. */ #define SVE_VQ_BYTES __SVE_VQ_BYTES /* bytes per quadword */ #define SVE_VQ_MIN __SVE_VQ_MIN #define SVE_VQ_MAX __SVE_VQ_MAX #define SVE_VL_MIN __SVE_VL_MIN #define SVE_VL_MAX __SVE_VL_MAX #define SVE_NUM_ZREGS __SVE_NUM_ZREGS #define SVE_NUM_PREGS __SVE_NUM_PREGS #define sve_vl_valid(vl) __sve_vl_valid(vl) #define sve_vq_from_vl(vl) __sve_vq_from_vl(vl) #define sve_vl_from_vq(vq) __sve_vl_from_vq(vq) /* * If the SVE registers are currently live for the thread at signal delivery, * sve_context.head.size >= * SVE_SIG_CONTEXT_SIZE(sve_vq_from_vl(sve_context.vl)) * and the register data may be accessed using the SVE_SIG_*() macros. * * If sve_context.head.size < * SVE_SIG_CONTEXT_SIZE(sve_vq_from_vl(sve_context.vl)), * the SVE registers were not live for the thread and no register data * is included: in this case, the SVE_SIG_*() macros should not be * used except for this check. * * The same convention applies when returning from a signal: a caller * will need to remove or resize the sve_context block if it wants to * make the SVE registers live when they were previously non-live or * vice-versa. This may require the the caller to allocate fresh * memory and/or move other context blocks in the signal frame. * * Changing the vector length during signal return is not permitted: * sve_context.vl must equal the thread's current vector length when * doing a sigreturn. * * * Note: for all these macros, the "vq" argument denotes the SVE * vector length in quadwords (i.e., units of 128 bits). * * The correct way to obtain vq is to use sve_vq_from_vl(vl). The * result is valid if and only if sve_vl_valid(vl) is true. This is * guaranteed for a struct sve_context written by the kernel. * * * Additional macros describe the contents and layout of the payload. * For each, SVE_SIG_x_OFFSET(args) is the start offset relative to * the start of struct sve_context, and SVE_SIG_x_SIZE(args) is the * size in bytes: * * x type description * - ---- ----------- * REGS the entire SVE context * * ZREGS __uint128_t[SVE_NUM_ZREGS][vq] all Z-registers * ZREG __uint128_t[vq] individual Z-register Zn * * PREGS uint16_t[SVE_NUM_PREGS][vq] all P-registers * PREG uint16_t[vq] individual P-register Pn * * FFR uint16_t[vq] first-fault status register * * Additional data might be appended in the future. * * Unlike vregs[] in fpsimd_context, each SVE scalable register (Z-, P- or FFR) * is encoded in memory in an endianness-invariant format, with the byte at * offset i from the start of the in-memory representation containing bits * [(7 + 8 * i) : (8 * i)] of the register value. */ #define SVE_SIG_ZREG_SIZE(vq) __SVE_ZREG_SIZE(vq) #define SVE_SIG_PREG_SIZE(vq) __SVE_PREG_SIZE(vq) #define SVE_SIG_FFR_SIZE(vq) __SVE_FFR_SIZE(vq) #define SVE_SIG_REGS_OFFSET \ ((sizeof(struct sve_context) + (__SVE_VQ_BYTES - 1)) \ / __SVE_VQ_BYTES * __SVE_VQ_BYTES) #define SVE_SIG_ZREGS_OFFSET \ (SVE_SIG_REGS_OFFSET + __SVE_ZREGS_OFFSET) #define SVE_SIG_ZREG_OFFSET(vq, n) \ (SVE_SIG_REGS_OFFSET + __SVE_ZREG_OFFSET(vq, n)) #define SVE_SIG_ZREGS_SIZE(vq) __SVE_ZREGS_SIZE(vq) #define SVE_SIG_PREGS_OFFSET(vq) \ (SVE_SIG_REGS_OFFSET + __SVE_PREGS_OFFSET(vq)) #define SVE_SIG_PREG_OFFSET(vq, n) \ (SVE_SIG_REGS_OFFSET + __SVE_PREG_OFFSET(vq, n)) #define SVE_SIG_PREGS_SIZE(vq) __SVE_PREGS_SIZE(vq) #define SVE_SIG_FFR_OFFSET(vq) \ (SVE_SIG_REGS_OFFSET + __SVE_FFR_OFFSET(vq)) #define SVE_SIG_REGS_SIZE(vq) \ (__SVE_FFR_OFFSET(vq) + __SVE_FFR_SIZE(vq)) #define SVE_SIG_CONTEXT_SIZE(vq) \ (SVE_SIG_REGS_OFFSET + SVE_SIG_REGS_SIZE(vq)) #endif /* _UAPI__ASM_SIGCONTEXT_H */