/* * Copyright (c) 2013-2022, Arm Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ #ifndef CONTEXT_H #define CONTEXT_H #include /******************************************************************************* * Constants that allow assembler code to access members of and the 'gp_regs' * structure at their correct offsets. ******************************************************************************/ #define CTX_GPREGS_OFFSET U(0x0) #define CTX_GPREG_X0 U(0x0) #define CTX_GPREG_X1 U(0x8) #define CTX_GPREG_X2 U(0x10) #define CTX_GPREG_X3 U(0x18) #define CTX_GPREG_X4 U(0x20) #define CTX_GPREG_X5 U(0x28) #define CTX_GPREG_X6 U(0x30) #define CTX_GPREG_X7 U(0x38) #define CTX_GPREG_X8 U(0x40) #define CTX_GPREG_X9 U(0x48) #define CTX_GPREG_X10 U(0x50) #define CTX_GPREG_X11 U(0x58) #define CTX_GPREG_X12 U(0x60) #define CTX_GPREG_X13 U(0x68) #define CTX_GPREG_X14 U(0x70) #define CTX_GPREG_X15 U(0x78) #define CTX_GPREG_X16 U(0x80) #define CTX_GPREG_X17 U(0x88) #define CTX_GPREG_X18 U(0x90) #define CTX_GPREG_X19 U(0x98) #define CTX_GPREG_X20 U(0xa0) #define CTX_GPREG_X21 U(0xa8) #define CTX_GPREG_X22 U(0xb0) #define CTX_GPREG_X23 U(0xb8) #define CTX_GPREG_X24 U(0xc0) #define CTX_GPREG_X25 U(0xc8) #define CTX_GPREG_X26 U(0xd0) #define CTX_GPREG_X27 U(0xd8) #define CTX_GPREG_X28 U(0xe0) #define CTX_GPREG_X29 U(0xe8) #define CTX_GPREG_LR U(0xf0) #define CTX_GPREG_SP_EL0 U(0xf8) #define CTX_GPREGS_END U(0x100) /******************************************************************************* * Constants that allow assembler code to access members of and the 'el3_state' * structure at their correct offsets. Note that some of the registers are only * 32-bits wide but are stored as 64-bit values for convenience ******************************************************************************/ #define CTX_EL3STATE_OFFSET (CTX_GPREGS_OFFSET + CTX_GPREGS_END) #define CTX_SCR_EL3 U(0x0) #define CTX_ESR_EL3 U(0x8) #define CTX_RUNTIME_SP U(0x10) #define CTX_SPSR_EL3 U(0x18) #define CTX_ELR_EL3 U(0x20) #define CTX_PMCR_EL0 U(0x28) #define CTX_IS_IN_EL3 U(0x30) #define CTX_CPTR_EL3 U(0x38) #define CTX_ZCR_EL3 U(0x40) #define CTX_EL3STATE_END U(0x50) /* Align to the next 16 byte boundary */ /******************************************************************************* * Constants that allow assembler code to access members of and the * 'el1_sys_regs' structure at their correct offsets. Note that some of the * registers are only 32-bits wide but are stored as 64-bit values for * convenience ******************************************************************************/ #define CTX_EL1_SYSREGS_OFFSET (CTX_EL3STATE_OFFSET + CTX_EL3STATE_END) #define CTX_SPSR_EL1 U(0x0) #define CTX_ELR_EL1 U(0x8) #define CTX_SCTLR_EL1 U(0x10) #define CTX_TCR_EL1 U(0x18) #define CTX_CPACR_EL1 U(0x20) #define CTX_CSSELR_EL1 U(0x28) #define CTX_SP_EL1 U(0x30) #define CTX_ESR_EL1 U(0x38) #define CTX_TTBR0_EL1 U(0x40) #define CTX_TTBR1_EL1 U(0x48) #define CTX_MAIR_EL1 U(0x50) #define CTX_AMAIR_EL1 U(0x58) #define CTX_ACTLR_EL1 U(0x60) #define CTX_TPIDR_EL1 U(0x68) #define CTX_TPIDR_EL0 U(0x70) #define CTX_TPIDRRO_EL0 U(0x78) #define CTX_PAR_EL1 U(0x80) #define CTX_FAR_EL1 U(0x88) #define CTX_AFSR0_EL1 U(0x90) #define CTX_AFSR1_EL1 U(0x98) #define CTX_CONTEXTIDR_EL1 U(0xa0) #define CTX_VBAR_EL1 U(0xa8) /* * If the platform is AArch64-only, there is no need to save and restore these * AArch32 registers. */ #if CTX_INCLUDE_AARCH32_REGS #define CTX_SPSR_ABT U(0xb0) /* Align to the next 16 byte boundary */ #define CTX_SPSR_UND U(0xb8) #define CTX_SPSR_IRQ U(0xc0) #define CTX_SPSR_FIQ U(0xc8) #define CTX_DACR32_EL2 U(0xd0) #define CTX_IFSR32_EL2 U(0xd8) #define CTX_AARCH32_END U(0xe0) /* Align to the next 16 byte boundary */ #else #define CTX_AARCH32_END U(0xb0) /* Align to the next 16 byte boundary */ #endif /* CTX_INCLUDE_AARCH32_REGS */ /* * If the timer registers aren't saved and restored, we don't have to reserve * space for them in the context */ #if NS_TIMER_SWITCH #define CTX_CNTP_CTL_EL0 (CTX_AARCH32_END + U(0x0)) #define CTX_CNTP_CVAL_EL0 (CTX_AARCH32_END + U(0x8)) #define CTX_CNTV_CTL_EL0 (CTX_AARCH32_END + U(0x10)) #define CTX_CNTV_CVAL_EL0 (CTX_AARCH32_END + U(0x18)) #define CTX_CNTKCTL_EL1 (CTX_AARCH32_END + U(0x20)) #define CTX_TIMER_SYSREGS_END (CTX_AARCH32_END + U(0x30)) /* Align to the next 16 byte boundary */ #else #define CTX_TIMER_SYSREGS_END CTX_AARCH32_END #endif /* NS_TIMER_SWITCH */ #if CTX_INCLUDE_MTE_REGS #define CTX_TFSRE0_EL1 (CTX_TIMER_SYSREGS_END + U(0x0)) #define CTX_TFSR_EL1 (CTX_TIMER_SYSREGS_END + U(0x8)) #define CTX_RGSR_EL1 (CTX_TIMER_SYSREGS_END + U(0x10)) #define CTX_GCR_EL1 (CTX_TIMER_SYSREGS_END + U(0x18)) /* Align to the next 16 byte boundary */ #define CTX_MTE_REGS_END (CTX_TIMER_SYSREGS_END + U(0x20)) #else #define CTX_MTE_REGS_END CTX_TIMER_SYSREGS_END #endif /* CTX_INCLUDE_MTE_REGS */ /* * End of system registers. */ #define CTX_EL1_SYSREGS_END CTX_MTE_REGS_END /* * EL2 register set */ #if CTX_INCLUDE_EL2_REGS /* For later discussion * ICH_AP0R_EL2 * ICH_AP1R_EL2 * AMEVCNTVOFF0_EL2 * AMEVCNTVOFF1_EL2 * ICH_LR_EL2 */ #define CTX_EL2_SYSREGS_OFFSET (CTX_EL1_SYSREGS_OFFSET + CTX_EL1_SYSREGS_END) #define CTX_ACTLR_EL2 U(0x0) #define CTX_AFSR0_EL2 U(0x8) #define CTX_AFSR1_EL2 U(0x10) #define CTX_AMAIR_EL2 U(0x18) #define CTX_CNTHCTL_EL2 U(0x20) #define CTX_CNTVOFF_EL2 U(0x28) #define CTX_CPTR_EL2 U(0x30) #define CTX_DBGVCR32_EL2 U(0x38) #define CTX_ELR_EL2 U(0x40) #define CTX_ESR_EL2 U(0x48) #define CTX_FAR_EL2 U(0x50) #define CTX_HACR_EL2 U(0x58) #define CTX_HCR_EL2 U(0x60) #define CTX_HPFAR_EL2 U(0x68) #define CTX_HSTR_EL2 U(0x70) #define CTX_ICC_SRE_EL2 U(0x78) #define CTX_ICH_HCR_EL2 U(0x80) #define CTX_ICH_VMCR_EL2 U(0x88) #define CTX_MAIR_EL2 U(0x90) #define CTX_MDCR_EL2 U(0x98) #define CTX_PMSCR_EL2 U(0xa0) #define CTX_SCTLR_EL2 U(0xa8) #define CTX_SPSR_EL2 U(0xb0) #define CTX_SP_EL2 U(0xb8) #define CTX_TCR_EL2 U(0xc0) #define CTX_TPIDR_EL2 U(0xc8) #define CTX_TTBR0_EL2 U(0xd0) #define CTX_VBAR_EL2 U(0xd8) #define CTX_VMPIDR_EL2 U(0xe0) #define CTX_VPIDR_EL2 U(0xe8) #define CTX_VTCR_EL2 U(0xf0) #define CTX_VTTBR_EL2 U(0xf8) // Only if MTE registers in use #define CTX_TFSR_EL2 U(0x100) #define CTX_MPAM2_EL2 U(0x108) #define CTX_MPAMHCR_EL2 U(0x110) #define CTX_MPAMVPM0_EL2 U(0x118) #define CTX_MPAMVPM1_EL2 U(0x120) #define CTX_MPAMVPM2_EL2 U(0x128) #define CTX_MPAMVPM3_EL2 U(0x130) #define CTX_MPAMVPM4_EL2 U(0x138) #define CTX_MPAMVPM5_EL2 U(0x140) #define CTX_MPAMVPM6_EL2 U(0x148) #define CTX_MPAMVPM7_EL2 U(0x150) #define CTX_MPAMVPMV_EL2 U(0x158) // Starting with Armv8.6 #define CTX_HDFGRTR_EL2 U(0x160) #define CTX_HAFGRTR_EL2 U(0x168) #define CTX_HDFGWTR_EL2 U(0x170) #define CTX_HFGITR_EL2 U(0x178) #define CTX_HFGRTR_EL2 U(0x180) #define CTX_HFGWTR_EL2 U(0x188) #define CTX_CNTPOFF_EL2 U(0x190) // Starting with Armv8.4 #define CTX_CONTEXTIDR_EL2 U(0x198) #define CTX_TTBR1_EL2 U(0x1a0) #define CTX_VDISR_EL2 U(0x1a8) #define CTX_VSESR_EL2 U(0x1b0) #define CTX_VNCR_EL2 U(0x1b8) #define CTX_TRFCR_EL2 U(0x1c0) // Starting with Armv8.5 #define CTX_SCXTNUM_EL2 U(0x1c8) // Register for FEAT_HCX #define CTX_HCRX_EL2 U(0x1d0) // Starting with Armv8.9 #define CTX_TCR2_EL2 U(0x1d8) #define CTX_POR_EL2 U(0x1e0) #define CTX_PIRE0_EL2 U(0x1e8) #define CTX_PIR_EL2 U(0x1f0) #define CTX_S2PIR_EL2 U(0x1f8) #define CTX_GCSCR_EL2 U(0x200) #define CTX_GCSPR_EL2 U(0x208) /* Align to the next 16 byte boundary */ #define CTX_EL2_SYSREGS_END U(0x210) #endif /* CTX_INCLUDE_EL2_REGS */ /******************************************************************************* * Constants that allow assembler code to access members of and the 'fp_regs' * structure at their correct offsets. ******************************************************************************/ #if CTX_INCLUDE_EL2_REGS # define CTX_FPREGS_OFFSET (CTX_EL2_SYSREGS_OFFSET + CTX_EL2_SYSREGS_END) #else # define CTX_FPREGS_OFFSET (CTX_EL1_SYSREGS_OFFSET + CTX_EL1_SYSREGS_END) #endif #if CTX_INCLUDE_FPREGS #define CTX_FP_Q0 U(0x0) #define CTX_FP_Q1 U(0x10) #define CTX_FP_Q2 U(0x20) #define CTX_FP_Q3 U(0x30) #define CTX_FP_Q4 U(0x40) #define CTX_FP_Q5 U(0x50) #define CTX_FP_Q6 U(0x60) #define CTX_FP_Q7 U(0x70) #define CTX_FP_Q8 U(0x80) #define CTX_FP_Q9 U(0x90) #define CTX_FP_Q10 U(0xa0) #define CTX_FP_Q11 U(0xb0) #define CTX_FP_Q12 U(0xc0) #define CTX_FP_Q13 U(0xd0) #define CTX_FP_Q14 U(0xe0) #define CTX_FP_Q15 U(0xf0) #define CTX_FP_Q16 U(0x100) #define CTX_FP_Q17 U(0x110) #define CTX_FP_Q18 U(0x120) #define CTX_FP_Q19 U(0x130) #define CTX_FP_Q20 U(0x140) #define CTX_FP_Q21 U(0x150) #define CTX_FP_Q22 U(0x160) #define CTX_FP_Q23 U(0x170) #define CTX_FP_Q24 U(0x180) #define CTX_FP_Q25 U(0x190) #define CTX_FP_Q26 U(0x1a0) #define CTX_FP_Q27 U(0x1b0) #define CTX_FP_Q28 U(0x1c0) #define CTX_FP_Q29 U(0x1d0) #define CTX_FP_Q30 U(0x1e0) #define CTX_FP_Q31 U(0x1f0) #define CTX_FP_FPSR U(0x200) #define CTX_FP_FPCR U(0x208) #if CTX_INCLUDE_AARCH32_REGS #define CTX_FP_FPEXC32_EL2 U(0x210) #define CTX_FPREGS_END U(0x220) /* Align to the next 16 byte boundary */ #else #define CTX_FPREGS_END U(0x210) /* Align to the next 16 byte boundary */ #endif #else #define CTX_FPREGS_END U(0) #endif /******************************************************************************* * Registers related to CVE-2018-3639 ******************************************************************************/ #define CTX_CVE_2018_3639_OFFSET (CTX_FPREGS_OFFSET + CTX_FPREGS_END) #define CTX_CVE_2018_3639_DISABLE U(0) #define CTX_CVE_2018_3639_END U(0x10) /* Align to the next 16 byte boundary */ /******************************************************************************* * Registers related to ARMv8.3-PAuth. ******************************************************************************/ #define CTX_PAUTH_REGS_OFFSET (CTX_CVE_2018_3639_OFFSET + CTX_CVE_2018_3639_END) #if CTX_INCLUDE_PAUTH_REGS #define CTX_PACIAKEY_LO U(0x0) #define CTX_PACIAKEY_HI U(0x8) #define CTX_PACIBKEY_LO U(0x10) #define CTX_PACIBKEY_HI U(0x18) #define CTX_PACDAKEY_LO U(0x20) #define CTX_PACDAKEY_HI U(0x28) #define CTX_PACDBKEY_LO U(0x30) #define CTX_PACDBKEY_HI U(0x38) #define CTX_PACGAKEY_LO U(0x40) #define CTX_PACGAKEY_HI U(0x48) #define CTX_PAUTH_REGS_END U(0x50) /* Align to the next 16 byte boundary */ #else #define CTX_PAUTH_REGS_END U(0) #endif /* CTX_INCLUDE_PAUTH_REGS */ #ifndef __ASSEMBLER__ #include #include /* * Common constants to help define the 'cpu_context' structure and its * members below. */ #define DWORD_SHIFT U(3) #define DEFINE_REG_STRUCT(name, num_regs) \ typedef struct name { \ uint64_t ctx_regs[num_regs]; \ } __aligned(16) name##_t /* Constants to determine the size of individual context structures */ #define CTX_GPREG_ALL (CTX_GPREGS_END >> DWORD_SHIFT) #define CTX_EL1_SYSREGS_ALL (CTX_EL1_SYSREGS_END >> DWORD_SHIFT) #if CTX_INCLUDE_EL2_REGS # define CTX_EL2_SYSREGS_ALL (CTX_EL2_SYSREGS_END >> DWORD_SHIFT) #endif #if CTX_INCLUDE_FPREGS # define CTX_FPREG_ALL (CTX_FPREGS_END >> DWORD_SHIFT) #endif #define CTX_EL3STATE_ALL (CTX_EL3STATE_END >> DWORD_SHIFT) #define CTX_CVE_2018_3639_ALL (CTX_CVE_2018_3639_END >> DWORD_SHIFT) #if CTX_INCLUDE_PAUTH_REGS # define CTX_PAUTH_REGS_ALL (CTX_PAUTH_REGS_END >> DWORD_SHIFT) #endif /* * AArch64 general purpose register context structure. Usually x0-x18, * lr are saved as the compiler is expected to preserve the remaining * callee saved registers if used by the C runtime and the assembler * does not touch the remaining. But in case of world switch during * exception handling, we need to save the callee registers too. */ DEFINE_REG_STRUCT(gp_regs, CTX_GPREG_ALL); /* * AArch64 EL1 system register context structure for preserving the * architectural state during world switches. */ DEFINE_REG_STRUCT(el1_sysregs, CTX_EL1_SYSREGS_ALL); /* * AArch64 EL2 system register context structure for preserving the * architectural state during world switches. */ #if CTX_INCLUDE_EL2_REGS DEFINE_REG_STRUCT(el2_sysregs, CTX_EL2_SYSREGS_ALL); #endif /* * AArch64 floating point register context structure for preserving * the floating point state during switches from one security state to * another. */ #if CTX_INCLUDE_FPREGS DEFINE_REG_STRUCT(fp_regs, CTX_FPREG_ALL); #endif /* * Miscellaneous registers used by EL3 firmware to maintain its state * across exception entries and exits */ DEFINE_REG_STRUCT(el3_state, CTX_EL3STATE_ALL); /* Function pointer used by CVE-2018-3639 dynamic mitigation */ DEFINE_REG_STRUCT(cve_2018_3639, CTX_CVE_2018_3639_ALL); /* Registers associated to ARMv8.3-PAuth */ #if CTX_INCLUDE_PAUTH_REGS DEFINE_REG_STRUCT(pauth, CTX_PAUTH_REGS_ALL); #endif /* * Macros to access members of any of the above structures using their * offsets */ #define read_ctx_reg(ctx, offset) ((ctx)->ctx_regs[(offset) >> DWORD_SHIFT]) #define write_ctx_reg(ctx, offset, val) (((ctx)->ctx_regs[(offset) >> DWORD_SHIFT]) \ = (uint64_t) (val)) /* * Top-level context structure which is used by EL3 firmware to preserve * the state of a core at the next lower EL in a given security state and * save enough EL3 meta data to be able to return to that EL and security * state. The context management library will be used to ensure that * SP_EL3 always points to an instance of this structure at exception * entry and exit. */ typedef struct cpu_context { gp_regs_t gpregs_ctx; el3_state_t el3state_ctx; el1_sysregs_t el1_sysregs_ctx; #if CTX_INCLUDE_EL2_REGS el2_sysregs_t el2_sysregs_ctx; #endif #if CTX_INCLUDE_FPREGS fp_regs_t fpregs_ctx; #endif cve_2018_3639_t cve_2018_3639_ctx; #if CTX_INCLUDE_PAUTH_REGS pauth_t pauth_ctx; #endif } cpu_context_t; /* Macros to access members of the 'cpu_context_t' structure */ #define get_el3state_ctx(h) (&((cpu_context_t *) h)->el3state_ctx) #if CTX_INCLUDE_FPREGS # define get_fpregs_ctx(h) (&((cpu_context_t *) h)->fpregs_ctx) #endif #define get_el1_sysregs_ctx(h) (&((cpu_context_t *) h)->el1_sysregs_ctx) #if CTX_INCLUDE_EL2_REGS # define get_el2_sysregs_ctx(h) (&((cpu_context_t *) h)->el2_sysregs_ctx) #endif #define get_gpregs_ctx(h) (&((cpu_context_t *) h)->gpregs_ctx) #define get_cve_2018_3639_ctx(h) (&((cpu_context_t *) h)->cve_2018_3639_ctx) #if CTX_INCLUDE_PAUTH_REGS # define get_pauth_ctx(h) (&((cpu_context_t *) h)->pauth_ctx) #endif /* * Compile time assertions related to the 'cpu_context' structure to * ensure that the assembler and the compiler view of the offsets of * the structure members is the same. */ CASSERT(CTX_GPREGS_OFFSET == __builtin_offsetof(cpu_context_t, gpregs_ctx), assert_core_context_gp_offset_mismatch); CASSERT(CTX_EL1_SYSREGS_OFFSET == __builtin_offsetof(cpu_context_t, el1_sysregs_ctx), assert_core_context_el1_sys_offset_mismatch); #if CTX_INCLUDE_EL2_REGS CASSERT(CTX_EL2_SYSREGS_OFFSET == __builtin_offsetof(cpu_context_t, el2_sysregs_ctx), assert_core_context_el2_sys_offset_mismatch); #endif #if CTX_INCLUDE_FPREGS CASSERT(CTX_FPREGS_OFFSET == __builtin_offsetof(cpu_context_t, fpregs_ctx), assert_core_context_fp_offset_mismatch); #endif CASSERT(CTX_EL3STATE_OFFSET == __builtin_offsetof(cpu_context_t, el3state_ctx), assert_core_context_el3state_offset_mismatch); CASSERT(CTX_CVE_2018_3639_OFFSET == __builtin_offsetof(cpu_context_t, cve_2018_3639_ctx), assert_core_context_cve_2018_3639_offset_mismatch); #if CTX_INCLUDE_PAUTH_REGS CASSERT(CTX_PAUTH_REGS_OFFSET == __builtin_offsetof(cpu_context_t, pauth_ctx), assert_core_context_pauth_offset_mismatch); #endif /* * Helper macro to set the general purpose registers that correspond to * parameters in an aapcs_64 call i.e. x0-x7 */ #define set_aapcs_args0(ctx, x0) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X0, x0); \ } while (0) #define set_aapcs_args1(ctx, x0, x1) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X1, x1); \ set_aapcs_args0(ctx, x0); \ } while (0) #define set_aapcs_args2(ctx, x0, x1, x2) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X2, x2); \ set_aapcs_args1(ctx, x0, x1); \ } while (0) #define set_aapcs_args3(ctx, x0, x1, x2, x3) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X3, x3); \ set_aapcs_args2(ctx, x0, x1, x2); \ } while (0) #define set_aapcs_args4(ctx, x0, x1, x2, x3, x4) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X4, x4); \ set_aapcs_args3(ctx, x0, x1, x2, x3); \ } while (0) #define set_aapcs_args5(ctx, x0, x1, x2, x3, x4, x5) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X5, x5); \ set_aapcs_args4(ctx, x0, x1, x2, x3, x4); \ } while (0) #define set_aapcs_args6(ctx, x0, x1, x2, x3, x4, x5, x6) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X6, x6); \ set_aapcs_args5(ctx, x0, x1, x2, x3, x4, x5); \ } while (0) #define set_aapcs_args7(ctx, x0, x1, x2, x3, x4, x5, x6, x7) do { \ write_ctx_reg(get_gpregs_ctx(ctx), CTX_GPREG_X7, x7); \ set_aapcs_args6(ctx, x0, x1, x2, x3, x4, x5, x6); \ } while (0) /******************************************************************************* * Function prototypes ******************************************************************************/ void el1_sysregs_context_save(el1_sysregs_t *regs); void el1_sysregs_context_restore(el1_sysregs_t *regs); #if CTX_INCLUDE_EL2_REGS void el2_sysregs_context_save_common(el2_sysregs_t *regs); void el2_sysregs_context_restore_common(el2_sysregs_t *regs); #if CTX_INCLUDE_MTE_REGS void el2_sysregs_context_save_mte(el2_sysregs_t *regs); void el2_sysregs_context_restore_mte(el2_sysregs_t *regs); #endif /* CTX_INCLUDE_MTE_REGS */ #if RAS_EXTENSION void el2_sysregs_context_save_ras(el2_sysregs_t *regs); void el2_sysregs_context_restore_ras(el2_sysregs_t *regs); #endif /* RAS_EXTENSION */ #endif /* CTX_INCLUDE_EL2_REGS */ #if CTX_INCLUDE_FPREGS void fpregs_context_save(fp_regs_t *regs); void fpregs_context_restore(fp_regs_t *regs); #endif #endif /* __ASSEMBLER__ */ #endif /* CONTEXT_H */