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Diffstat (limited to 'arch/x86/include/asm/fpu/types.h')
| -rw-r--r-- | arch/x86/include/asm/fpu/types.h | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h new file mode 100644 index 000000000..eb7cd1139 --- /dev/null +++ b/arch/x86/include/asm/fpu/types.h @@ -0,0 +1,585 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * FPU data structures: + */ +#ifndef _ASM_X86_FPU_H +#define _ASM_X86_FPU_H + +/* + * 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_RSRVD_COMP_11, + XFEATURE_RSRVD_COMP_12, + 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_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 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[0]; +} __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 it's 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 */ |