/* SPDX-License-Identifier: GPL-2.0 */ /* * FPU data structures: */ #ifndef _ASM_X86_FPU_H #define _ASM_X86_FPU_H #include /* * The legacy x87 FPU state format, as saved by FSAVE and * restored by the FRSTOR instructions: */ struct fregs_state { u32 cwd; /* FPU Control Word */ u32 swd; /* FPU Status Word */ u32 twd; /* FPU Tag Word */ u32 fip; /* FPU IP Offset */ u32 fcs; /* FPU IP Selector */ u32 foo; /* FPU Operand Pointer Offset */ u32 fos; /* FPU Operand Pointer Selector */ /* 8*10 bytes for each FP-reg = 80 bytes: */ u32 st_space[20]; /* Software status information [not touched by FSAVE]: */ u32 status; }; /* * The legacy fx SSE/MMX FPU state format, as saved by FXSAVE and * restored by the FXRSTOR instructions. It's similar to the FSAVE * format, but differs in some areas, plus has extensions at * the end for the XMM registers. */ struct fxregs_state { u16 cwd; /* Control Word */ u16 swd; /* Status Word */ u16 twd; /* Tag Word */ u16 fop; /* Last Instruction Opcode */ union { struct { u64 rip; /* Instruction Pointer */ u64 rdp; /* Data Pointer */ }; struct { u32 fip; /* FPU IP Offset */ u32 fcs; /* FPU IP Selector */ u32 foo; /* FPU Operand Offset */ u32 fos; /* FPU Operand Selector */ }; }; u32 mxcsr; /* MXCSR Register State */ u32 mxcsr_mask; /* MXCSR Mask */ /* 8*16 bytes for each FP-reg = 128 bytes: */ u32 st_space[32]; /* 16*16 bytes for each XMM-reg = 256 bytes: */ u32 xmm_space[64]; u32 padding[12]; union { u32 padding1[12]; u32 sw_reserved[12]; }; } __attribute__((aligned(16))); /* Default value for fxregs_state.mxcsr: */ #define MXCSR_DEFAULT 0x1f80 /* Copy both mxcsr & mxcsr_flags with a single u64 memcpy: */ #define MXCSR_AND_FLAGS_SIZE sizeof(u64) /* * Software based FPU emulation state. This is arbitrary really, * it matches the x87 format to make it easier to understand: */ struct swregs_state { u32 cwd; u32 swd; u32 twd; u32 fip; u32 fcs; u32 foo; u32 fos; /* 8*10 bytes for each FP-reg = 80 bytes: */ u32 st_space[20]; u8 ftop; u8 changed; u8 lookahead; u8 no_update; u8 rm; u8 alimit; struct math_emu_info *info; u32 entry_eip; }; /* * List of XSAVE features Linux knows about: */ enum xfeature { XFEATURE_FP, XFEATURE_SSE, /* * Values above here are "legacy states". * Those below are "extended states". */ XFEATURE_YMM, XFEATURE_BNDREGS, XFEATURE_BNDCSR, XFEATURE_OPMASK, XFEATURE_ZMM_Hi256, XFEATURE_Hi16_ZMM, XFEATURE_PT_UNIMPLEMENTED_SO_FAR, XFEATURE_PKRU, XFEATURE_PASID, XFEATURE_CET_USER, XFEATURE_CET_KERNEL_UNUSED, XFEATURE_RSRVD_COMP_13, XFEATURE_RSRVD_COMP_14, XFEATURE_LBR, XFEATURE_RSRVD_COMP_16, XFEATURE_XTILE_CFG, XFEATURE_XTILE_DATA, XFEATURE_MAX, }; #define XFEATURE_MASK_FP (1 << XFEATURE_FP) #define XFEATURE_MASK_SSE (1 << XFEATURE_SSE) #define XFEATURE_MASK_YMM (1 << XFEATURE_YMM) #define XFEATURE_MASK_BNDREGS (1 << XFEATURE_BNDREGS) #define XFEATURE_MASK_BNDCSR (1 << XFEATURE_BNDCSR) #define XFEATURE_MASK_OPMASK (1 << XFEATURE_OPMASK) #define XFEATURE_MASK_ZMM_Hi256 (1 << XFEATURE_ZMM_Hi256) #define XFEATURE_MASK_Hi16_ZMM (1 << XFEATURE_Hi16_ZMM) #define XFEATURE_MASK_PT (1 << XFEATURE_PT_UNIMPLEMENTED_SO_FAR) #define XFEATURE_MASK_PKRU (1 << XFEATURE_PKRU) #define XFEATURE_MASK_PASID (1 << XFEATURE_PASID) #define XFEATURE_MASK_CET_USER (1 << XFEATURE_CET_USER) #define XFEATURE_MASK_CET_KERNEL (1 << XFEATURE_CET_KERNEL_UNUSED) #define XFEATURE_MASK_LBR (1 << XFEATURE_LBR) #define XFEATURE_MASK_XTILE_CFG (1 << XFEATURE_XTILE_CFG) #define XFEATURE_MASK_XTILE_DATA (1 << XFEATURE_XTILE_DATA) #define XFEATURE_MASK_FPSSE (XFEATURE_MASK_FP | XFEATURE_MASK_SSE) #define XFEATURE_MASK_AVX512 (XFEATURE_MASK_OPMASK \ | XFEATURE_MASK_ZMM_Hi256 \ | XFEATURE_MASK_Hi16_ZMM) #ifdef CONFIG_X86_64 # define XFEATURE_MASK_XTILE (XFEATURE_MASK_XTILE_DATA \ | XFEATURE_MASK_XTILE_CFG) #else # define XFEATURE_MASK_XTILE (0) #endif #define FIRST_EXTENDED_XFEATURE XFEATURE_YMM struct reg_128_bit { u8 regbytes[128/8]; }; struct reg_256_bit { u8 regbytes[256/8]; }; struct reg_512_bit { u8 regbytes[512/8]; }; struct reg_1024_byte { u8 regbytes[1024]; }; /* * State component 2: * * There are 16x 256-bit AVX registers named YMM0-YMM15. * The low 128 bits are aliased to the 16 SSE registers (XMM0-XMM15) * and are stored in 'struct fxregs_state::xmm_space[]' in the * "legacy" area. * * The high 128 bits are stored here. */ struct ymmh_struct { struct reg_128_bit hi_ymm[16]; } __packed; /* Intel MPX support: */ struct mpx_bndreg { u64 lower_bound; u64 upper_bound; } __packed; /* * State component 3 is used for the 4 128-bit bounds registers */ struct mpx_bndreg_state { struct mpx_bndreg bndreg[4]; } __packed; /* * State component 4 is used for the 64-bit user-mode MPX * configuration register BNDCFGU and the 64-bit MPX status * register BNDSTATUS. We call the pair "BNDCSR". */ struct mpx_bndcsr { u64 bndcfgu; u64 bndstatus; } __packed; /* * The BNDCSR state is padded out to be 64-bytes in size. */ struct mpx_bndcsr_state { union { struct mpx_bndcsr bndcsr; u8 pad_to_64_bytes[64]; }; } __packed; /* AVX-512 Components: */ /* * State component 5 is used for the 8 64-bit opmask registers * k0-k7 (opmask state). */ struct avx_512_opmask_state { u64 opmask_reg[8]; } __packed; /* * State component 6 is used for the upper 256 bits of the * registers ZMM0-ZMM15. These 16 256-bit values are denoted * ZMM0_H-ZMM15_H (ZMM_Hi256 state). */ struct avx_512_zmm_uppers_state { struct reg_256_bit zmm_upper[16]; } __packed; /* * State component 7 is used for the 16 512-bit registers * ZMM16-ZMM31 (Hi16_ZMM state). */ struct avx_512_hi16_state { struct reg_512_bit hi16_zmm[16]; } __packed; /* * State component 9: 32-bit PKRU register. The state is * 8 bytes long but only 4 bytes is used currently. */ struct pkru_state { u32 pkru; u32 pad; } __packed; /* * State component 11 is Control-flow Enforcement user states */ struct cet_user_state { /* user control-flow settings */ u64 user_cet; /* user shadow stack pointer */ u64 user_ssp; }; /* * State component 15: Architectural LBR configuration state. * The size of Arch LBR state depends on the number of LBRs (lbr_depth). */ struct lbr_entry { u64 from; u64 to; u64 info; }; struct arch_lbr_state { u64 lbr_ctl; u64 lbr_depth; u64 ler_from; u64 ler_to; u64 ler_info; struct lbr_entry entries[]; }; /* * State component 17: 64-byte tile configuration register. */ struct xtile_cfg { u64 tcfg[8]; } __packed; /* * State component 18: 1KB tile data register. * Each register represents 16 64-byte rows of the matrix * data. But the number of registers depends on the actual * implementation. */ struct xtile_data { struct reg_1024_byte tmm; } __packed; /* * State component 10 is supervisor state used for context-switching the * PASID state. */ struct ia32_pasid_state { u64 pasid; } __packed; struct xstate_header { u64 xfeatures; u64 xcomp_bv; u64 reserved[6]; } __attribute__((packed)); /* * xstate_header.xcomp_bv[63] indicates that the extended_state_area * is in compacted format. */ #define XCOMP_BV_COMPACTED_FORMAT ((u64)1 << 63) /* * This is our most modern FPU state format, as saved by the XSAVE * and restored by the XRSTOR instructions. * * It consists of a legacy fxregs portion, an xstate header and * subsequent areas as defined by the xstate header. Not all CPUs * support all the extensions, so the size of the extended area * can vary quite a bit between CPUs. */ struct xregs_state { struct fxregs_state i387; struct xstate_header header; u8 extended_state_area[]; } __attribute__ ((packed, aligned (64))); /* * This is a union of all the possible FPU state formats * put together, so that we can pick the right one runtime. * * The size of the structure is determined by the largest * member - which is the xsave area. The padding is there * to ensure that statically-allocated task_structs (just * the init_task today) have enough space. */ union fpregs_state { struct fregs_state fsave; struct fxregs_state fxsave; struct swregs_state soft; struct xregs_state xsave; u8 __padding[PAGE_SIZE]; }; struct fpstate { /* @kernel_size: The size of the kernel register image */ unsigned int size; /* @user_size: The size in non-compacted UABI format */ unsigned int user_size; /* @xfeatures: xfeatures for which the storage is sized */ u64 xfeatures; /* @user_xfeatures: xfeatures valid in UABI buffers */ u64 user_xfeatures; /* @xfd: xfeatures disabled to trap userspace use. */ u64 xfd; /* @is_valloc: Indicator for dynamically allocated state */ unsigned int is_valloc : 1; /* @is_guest: Indicator for guest state (KVM) */ unsigned int is_guest : 1; /* * @is_confidential: Indicator for KVM confidential mode. * The FPU registers are restored by the * vmentry firmware from encrypted guest * memory. On vmexit the FPU registers are * saved by firmware to encrypted guest memory * and the registers are scrubbed before * returning to the host. So there is no * content which is worth saving and restoring. * The fpstate has to be there so that * preemption and softirq FPU usage works * without special casing. */ unsigned int is_confidential : 1; /* @in_use: State is in use */ unsigned int in_use : 1; /* @regs: The register state union for all supported formats */ union fpregs_state regs; /* @regs is dynamically sized! Don't add anything after @regs! */ } __aligned(64); #define FPU_GUEST_PERM_LOCKED BIT_ULL(63) struct fpu_state_perm { /* * @__state_perm: * * This bitmap indicates the permission for state components, which * are available to a thread group. The permission prctl() sets the * enabled state bits in thread_group_leader()->thread.fpu. * * All run time operations use the per thread information in the * currently active fpu.fpstate which contains the xfeature masks * and sizes for kernel and user space. * * This master permission field is only to be used when * task.fpu.fpstate based checks fail to validate whether the task * is allowed to expand its xfeatures set which requires to * allocate a larger sized fpstate buffer. * * Do not access this field directly. Use the provided helper * function. Unlocked access is possible for quick checks. */ u64 __state_perm; /* * @__state_size: * * The size required for @__state_perm. Only valid to access * with sighand locked. */ unsigned int __state_size; /* * @__user_state_size: * * The size required for @__state_perm user part. Only valid to * access with sighand locked. */ unsigned int __user_state_size; }; /* * Highest level per task FPU state data structure that * contains the FPU register state plus various FPU * state fields: */ struct fpu { /* * @last_cpu: * * Records the last CPU on which this context was loaded into * FPU registers. (In the lazy-restore case we might be * able to reuse FPU registers across multiple context switches * this way, if no intermediate task used the FPU.) * * A value of -1 is used to indicate that the FPU state in context * memory is newer than the FPU state in registers, and that the * FPU state should be reloaded next time the task is run. */ unsigned int last_cpu; /* * @avx512_timestamp: * * Records the timestamp of AVX512 use during last context switch. */ unsigned long avx512_timestamp; /* * @fpstate: * * Pointer to the active struct fpstate. Initialized to * point at @__fpstate below. */ struct fpstate *fpstate; /* * @__task_fpstate: * * Pointer to an inactive struct fpstate. Initialized to NULL. Is * used only for KVM support to swap out the regular task fpstate. */ struct fpstate *__task_fpstate; /* * @perm: * * Permission related information */ struct fpu_state_perm perm; /* * @guest_perm: * * Permission related information for guest pseudo FPUs */ struct fpu_state_perm guest_perm; /* * @__fpstate: * * Initial in-memory storage for FPU registers which are saved in * context switch and when the kernel uses the FPU. The registers * are restored from this storage on return to user space if they * are not longer containing the tasks FPU register state. */ struct fpstate __fpstate; /* * WARNING: '__fpstate' is dynamically-sized. Do not put * anything after it here. */ }; /* * Guest pseudo FPU container */ struct fpu_guest { /* * @xfeatures: xfeature bitmap of features which are * currently enabled for the guest vCPU. */ u64 xfeatures; /* * @perm: xfeature bitmap of features which are * permitted to be enabled for the guest * vCPU. */ u64 perm; /* * @xfd_err: Save the guest value. */ u64 xfd_err; /* * @uabi_size: Size required for save/restore */ unsigned int uabi_size; /* * @fpstate: Pointer to the allocated guest fpstate */ struct fpstate *fpstate; }; /* * FPU state configuration data. Initialized at boot time. Read only after init. */ struct fpu_state_config { /* * @max_size: * * The maximum size of the register state buffer. Includes all * supported features except independent managed features. */ unsigned int max_size; /* * @default_size: * * The default size of the register state buffer. Includes all * supported features except independent managed features and * features which have to be requested by user space before usage. */ unsigned int default_size; /* * @max_features: * * The maximum supported features bitmap. Does not include * independent managed features. */ u64 max_features; /* * @default_features: * * The default supported features bitmap. Does not include * independent managed features and features which have to * be requested by user space before usage. */ u64 default_features; /* * @legacy_features: * * Features which can be reported back to user space * even without XSAVE support, i.e. legacy features FP + SSE */ u64 legacy_features; }; /* FPU state configuration information */ extern struct fpu_state_config fpu_kernel_cfg, fpu_user_cfg; #endif /* _ASM_X86_FPU_H */