cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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xstate.h (4391B)

      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/fpu/api.h>
     10#include <asm/user.h>
     11
     12/* Bit 63 of XCR0 is reserved for future expansion */
     13#define XFEATURE_MASK_EXTEND	(~(XFEATURE_MASK_FPSSE | (1ULL << 63)))
     14
     15#define XSTATE_CPUID		0x0000000d
     16
     17#define TILE_CPUID		0x0000001d
     18
     19#define FXSAVE_SIZE	512
     20
     21#define XSAVE_HDR_SIZE	    64
     22#define XSAVE_HDR_OFFSET    FXSAVE_SIZE
     23
     24#define XSAVE_YMM_SIZE	    256
     25#define XSAVE_YMM_OFFSET    (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
     26
     27#define XSAVE_ALIGNMENT     64
     28
     29/* All currently supported user features */
     30#define XFEATURE_MASK_USER_SUPPORTED (XFEATURE_MASK_FP | \
     31				      XFEATURE_MASK_SSE | \
     32				      XFEATURE_MASK_YMM | \
     33				      XFEATURE_MASK_OPMASK | \
     34				      XFEATURE_MASK_ZMM_Hi256 | \
     35				      XFEATURE_MASK_Hi16_ZMM	 | \
     36				      XFEATURE_MASK_PKRU | \
     37				      XFEATURE_MASK_BNDREGS | \
     38				      XFEATURE_MASK_BNDCSR | \
     39				      XFEATURE_MASK_XTILE)
     40
     41/*
     42 * Features which are restored when returning to user space.
     43 * PKRU is not restored on return to user space because PKRU
     44 * is switched eagerly in switch_to() and flush_thread()
     45 */
     46#define XFEATURE_MASK_USER_RESTORE	\
     47	(XFEATURE_MASK_USER_SUPPORTED & ~XFEATURE_MASK_PKRU)
     48
     49/* Features which are dynamically enabled for a process on request */
     50#define XFEATURE_MASK_USER_DYNAMIC	XFEATURE_MASK_XTILE_DATA
     51
     52/* All currently supported supervisor features */
     53#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID)
     54
     55/*
     56 * A supervisor state component may not always contain valuable information,
     57 * and its size may be huge. Saving/restoring such supervisor state components
     58 * at each context switch can cause high CPU and space overhead, which should
     59 * be avoided. Such supervisor state components should only be saved/restored
     60 * on demand. The on-demand supervisor features are set in this mask.
     61 *
     62 * Unlike the existing supported supervisor features, an independent supervisor
     63 * feature does not allocate a buffer in task->fpu, and the corresponding
     64 * supervisor state component cannot be saved/restored at each context switch.
     65 *
     66 * To support an independent supervisor feature, a developer should follow the
     67 * dos and don'ts as below:
     68 * - Do dynamically allocate a buffer for the supervisor state component.
     69 * - Do manually invoke the XSAVES/XRSTORS instruction to save/restore the
     70 *   state component to/from the buffer.
     71 * - Don't set the bit corresponding to the independent supervisor feature in
     72 *   IA32_XSS at run time, since it has been set at boot time.
     73 */
     74#define XFEATURE_MASK_INDEPENDENT (XFEATURE_MASK_LBR)
     75
     76/*
     77 * Unsupported supervisor features. When a supervisor feature in this mask is
     78 * supported in the future, move it to the supported supervisor feature mask.
     79 */
     80#define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED (XFEATURE_MASK_PT)
     81
     82/* All supervisor states including supported and unsupported states. */
     83#define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \
     84				      XFEATURE_MASK_INDEPENDENT | \
     85				      XFEATURE_MASK_SUPERVISOR_UNSUPPORTED)
     86
     87/*
     88 * The feature mask required to restore FPU state:
     89 * - All user states which are not eagerly switched in switch_to()/exec()
     90 * - The suporvisor states
     91 */
     92#define XFEATURE_MASK_FPSTATE	(XFEATURE_MASK_USER_RESTORE | \
     93				 XFEATURE_MASK_SUPERVISOR_SUPPORTED)
     94
     95/*
     96 * Features in this mask have space allocated in the signal frame, but may not
     97 * have that space initialized when the feature is in its init state.
     98 */
     99#define XFEATURE_MASK_SIGFRAME_INITOPT	(XFEATURE_MASK_XTILE | \
    100					 XFEATURE_MASK_USER_DYNAMIC)
    101
    102extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
    103
    104extern void __init update_regset_xstate_info(unsigned int size,
    105					     u64 xstate_mask);
    106
    107int xfeature_size(int xfeature_nr);
    108
    109void xsaves(struct xregs_state *xsave, u64 mask);
    110void xrstors(struct xregs_state *xsave, u64 mask);
    111
    112int xfd_enable_feature(u64 xfd_err);
    113
    114#ifdef CONFIG_X86_64
    115DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic);
    116#endif
    117
    118#ifdef CONFIG_X86_64
    119DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic);
    120
    121static __always_inline __pure bool fpu_state_size_dynamic(void)
    122{
    123	return static_branch_unlikely(&__fpu_state_size_dynamic);
    124}
    125#else
    126static __always_inline __pure bool fpu_state_size_dynamic(void)
    127{
    128	return false;
    129}
    130#endif
    131
    132#endif