1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_X86_XSAVE_H 3 #define __ASM_X86_XSAVE_H 4 5 #include <linux/uaccess.h> 6 #include <linux/types.h> 7 8 #include <asm/processor.h> 9 #include <asm/user.h> 10 11 /* Bit 63 of XCR0 is reserved for future expansion */ 12 #define XFEATURE_MASK_EXTEND (~(XFEATURE_MASK_FPSSE | (1ULL << 63))) 13 14 #define XSTATE_CPUID 0x0000000d 15 16 #define FXSAVE_SIZE 512 17 18 #define XSAVE_HDR_SIZE 64 19 #define XSAVE_HDR_OFFSET FXSAVE_SIZE 20 21 #define XSAVE_YMM_SIZE 256 22 #define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET) 23 24 #define XSAVE_ALIGNMENT 64 25 26 /* All currently supported user features */ 27 #define XFEATURE_MASK_USER_SUPPORTED (XFEATURE_MASK_FP | \ 28 XFEATURE_MASK_SSE | \ 29 XFEATURE_MASK_YMM | \ 30 XFEATURE_MASK_OPMASK | \ 31 XFEATURE_MASK_ZMM_Hi256 | \ 32 XFEATURE_MASK_Hi16_ZMM | \ 33 XFEATURE_MASK_PKRU | \ 34 XFEATURE_MASK_BNDREGS | \ 35 XFEATURE_MASK_BNDCSR) 36 37 /* All currently supported supervisor features */ 38 #define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID) 39 40 /* 41 * A supervisor state component may not always contain valuable information, 42 * and its size may be huge. Saving/restoring such supervisor state components 43 * at each context switch can cause high CPU and space overhead, which should 44 * be avoided. Such supervisor state components should only be saved/restored 45 * on demand. The on-demand dynamic supervisor features are set in this mask. 46 * 47 * Unlike the existing supported supervisor features, a dynamic supervisor 48 * feature does not allocate a buffer in task->fpu, and the corresponding 49 * supervisor state component cannot be saved/restored at each context switch. 50 * 51 * To support a dynamic supervisor feature, a developer should follow the 52 * dos and don'ts as below: 53 * - Do dynamically allocate a buffer for the supervisor state component. 54 * - Do manually invoke the XSAVES/XRSTORS instruction to save/restore the 55 * state component to/from the buffer. 56 * - Don't set the bit corresponding to the dynamic supervisor feature in 57 * IA32_XSS at run time, since it has been set at boot time. 58 */ 59 #define XFEATURE_MASK_DYNAMIC (XFEATURE_MASK_LBR) 60 61 /* 62 * Unsupported supervisor features. When a supervisor feature in this mask is 63 * supported in the future, move it to the supported supervisor feature mask. 64 */ 65 #define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED (XFEATURE_MASK_PT) 66 67 /* All supervisor states including supported and unsupported states. */ 68 #define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \ 69 XFEATURE_MASK_DYNAMIC | \ 70 XFEATURE_MASK_SUPERVISOR_UNSUPPORTED) 71 72 #ifdef CONFIG_X86_64 73 #define REX_PREFIX "0x48, " 74 #else 75 #define REX_PREFIX 76 #endif 77 78 extern u64 xfeatures_mask_all; 79 80 static inline u64 xfeatures_mask_supervisor(void) 81 { 82 return xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_SUPPORTED; 83 } 84 85 static inline u64 xfeatures_mask_user(void) 86 { 87 return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED; 88 } 89 90 static inline u64 xfeatures_mask_dynamic(void) 91 { 92 if (!boot_cpu_has(X86_FEATURE_ARCH_LBR)) 93 return XFEATURE_MASK_DYNAMIC & ~XFEATURE_MASK_LBR; 94 95 return XFEATURE_MASK_DYNAMIC; 96 } 97 98 extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; 99 100 extern void __init update_regset_xstate_info(unsigned int size, 101 u64 xstate_mask); 102 103 void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr); 104 const void *get_xsave_field_ptr(int xfeature_nr); 105 int using_compacted_format(void); 106 int xfeature_size(int xfeature_nr); 107 struct membuf; 108 void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave); 109 int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf); 110 int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf); 111 void copy_supervisor_to_kernel(struct xregs_state *xsave); 112 void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask); 113 void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask); 114 115 116 /* Validate an xstate header supplied by userspace (ptrace or sigreturn) */ 117 int validate_user_xstate_header(const struct xstate_header *hdr); 118 119 #endif 120