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diff --git a/arch/arm64/include/uapi/asm/sigcontext.h b/arch/arm64/include/uapi/asm/sigcontext.h
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+/* 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 <http://www.gnu.org/licenses/>.
+ */
+#ifndef _UAPI__ASM_SIGCONTEXT_H
+#define _UAPI__ASM_SIGCONTEXT_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+/*
+ * 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 flags;
+ __u16 __reserved[2];
+};
+
+#define SVE_SIG_FLAG_SM 0x1 /* Context describes streaming mode */
+
+#define ZA_MAGIC 0x54366345
+
+struct za_context {
+ struct _aarch64_ctx head;
+ __u16 vl;
+ __u16 __reserved[3];
+};
+
+#endif /* !__ASSEMBLY__ */
+
+#include <asm/sve_context.h>
+
+/*
+ * 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.rst 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 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.
+ *
+ * On systems with support for SME the SVE register state may reflect either
+ * streaming or non-streaming mode. In streaming mode the streaming mode
+ * vector length will be used and the flag SVE_SIG_FLAG_SM will be set in
+ * the flags field. It is permitted to enter or leave streaming mode in
+ * a signal return, applications should take care to ensure that any difference
+ * in vector length between the two modes is handled, including any resizing
+ * and movement of context blocks.
+ *
+ * Note: for all these macros, the "vq" argument denotes the 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))
+
+/*
+ * If the ZA register is enabled for the thread at signal delivery then,
+ * za_context.head.size >= ZA_SIG_CONTEXT_SIZE(sve_vq_from_vl(za_context.vl))
+ * and the register data may be accessed using the ZA_SIG_*() macros.
+ *
+ * If za_context.head.size < ZA_SIG_CONTEXT_SIZE(sve_vq_from_vl(za_context.vl))
+ * then ZA was not enabled and no register data was included in which case
+ * ZA register was not enabled for the thread and no register data
+ * the ZA_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 za_context block if it wants to
+ * enable the ZA register when it was previously non-live or vice-versa.
+ * This may require 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:
+ * za_context.vl must equal the thread's current SME vector length when
+ * doing a sigreturn.
+ */
+
+#define ZA_SIG_REGS_OFFSET \
+ ((sizeof(struct za_context) + (__SVE_VQ_BYTES - 1)) \
+ / __SVE_VQ_BYTES * __SVE_VQ_BYTES)
+
+#define ZA_SIG_REGS_SIZE(vq) ((vq * __SVE_VQ_BYTES) * (vq * __SVE_VQ_BYTES))
+
+#define ZA_SIG_ZAV_OFFSET(vq, n) (ZA_SIG_REGS_OFFSET + \
+ (SVE_SIG_ZREG_SIZE(vq) * n))
+
+#define ZA_SIG_CONTEXT_SIZE(vq) \
+ (ZA_SIG_REGS_OFFSET + ZA_SIG_REGS_SIZE(vq))
+
+#endif /* _UAPI__ASM_SIGCONTEXT_H */