summaryrefslogtreecommitdiff
path: root/arch/arm64/include/uapi/asm
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/include/uapi/asm')
-rw-r--r--arch/arm64/include/uapi/asm/kvm.h7
-rw-r--r--arch/arm64/include/uapi/asm/ptrace.h12
-rw-r--r--arch/arm64/include/uapi/asm/sigcontext.h14
3 files changed, 28 insertions, 5 deletions
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 7b7ac0f6cec9..d819a3e8b552 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -260,6 +260,13 @@ struct kvm_vcpu_events {
KVM_REG_SIZE_U256 | \
((i) & (KVM_ARM64_SVE_MAX_SLICES - 1)))
+/*
+ * Register values for KVM_REG_ARM64_SVE_ZREG(), KVM_REG_ARM64_SVE_PREG() and
+ * KVM_REG_ARM64_SVE_FFR() are represented in memory in an endianness-
+ * invariant layout which differs from the layout used for the FPSIMD
+ * V-registers on big-endian systems: see sigcontext.h for more explanation.
+ */
+
#define KVM_ARM64_SVE_VQ_MIN __SVE_VQ_MIN
#define KVM_ARM64_SVE_VQ_MAX __SVE_VQ_MAX
diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h
index d78623acb649..e932284993d4 100644
--- a/arch/arm64/include/uapi/asm/ptrace.h
+++ b/arch/arm64/include/uapi/asm/ptrace.h
@@ -65,8 +65,6 @@
#ifndef __ASSEMBLY__
-#include <linux/prctl.h>
-
/*
* User structures for general purpose, floating point and debug registers.
*/
@@ -113,10 +111,10 @@ struct user_sve_header {
/*
* Common SVE_PT_* flags:
- * These must be kept in sync with prctl interface in <linux/ptrace.h>
+ * These must be kept in sync with prctl interface in <linux/prctl.h>
*/
-#define SVE_PT_VL_INHERIT (PR_SVE_VL_INHERIT >> 16)
-#define SVE_PT_VL_ONEXEC (PR_SVE_SET_VL_ONEXEC >> 16)
+#define SVE_PT_VL_INHERIT ((1 << 17) /* PR_SVE_VL_INHERIT */ >> 16)
+#define SVE_PT_VL_ONEXEC ((1 << 18) /* PR_SVE_SET_VL_ONEXEC */ >> 16)
/*
@@ -176,6 +174,10 @@ struct user_sve_header {
* FPCR uint32_t FPCR
*
* Additional data might be appended in the future.
+ *
+ * The Z-, P- and FFR registers are represented in memory in an endianness-
+ * invariant layout which differs from the layout used for the FPSIMD
+ * V-registers on big-endian systems: see sigcontext.h for more explanation.
*/
#define SVE_PT_SVE_ZREG_SIZE(vq) __SVE_ZREG_SIZE(vq)
diff --git a/arch/arm64/include/uapi/asm/sigcontext.h b/arch/arm64/include/uapi/asm/sigcontext.h
index 5f3c0cec5af9..3d448a0bb225 100644
--- a/arch/arm64/include/uapi/asm/sigcontext.h
+++ b/arch/arm64/include/uapi/asm/sigcontext.h
@@ -77,6 +77,15 @@ struct fpsimd_context {
__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
@@ -204,6 +213,11 @@ struct sve_context {
* 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)