LXR linux/arch/x86/kernel/cpu/sgx/encl.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/**
   3 * Copyright(c) 2016-20 Intel Corporation.
   4 *
   5 * Contains the software defined data structures for enclaves.
   6 */
   7#ifndef _X86_ENCL_H
   8#define _X86_ENCL_H
   9
  10#include <linux/cpumask.h>
  11#include <linux/kref.h>
  12#include <linux/list.h>
  13#include <linux/mm_types.h>
  14#include <linux/mmu_notifier.h>
  15#include <linux/mutex.h>
  16#include <linux/notifier.h>
  17#include <linux/srcu.h>
  18#include <linux/workqueue.h>
  19#include <linux/xarray.h>
  20#include "sgx.h"
  21
  22/* 'desc' bits holding the offset in the VA (version array) page. */
  23#define SGX_ENCL_PAGE_VA_OFFSET_MASK    GENMASK_ULL(11, 3)
  24
  25/* 'desc' bit marking that the page is being reclaimed. */
  26#define SGX_ENCL_PAGE_BEING_RECLAIMED   BIT(3)
  27
  28struct sgx_encl_page {
  29        unsigned long desc;
  30        unsigned long vm_max_prot_bits;
  31        struct sgx_epc_page *epc_page;
  32        struct sgx_encl *encl;
  33        struct sgx_va_page *va_page;
  34};
  35
  36enum sgx_encl_flags {
  37        SGX_ENCL_IOCTL          = BIT(0),
  38        SGX_ENCL_DEBUG          = BIT(1),
  39        SGX_ENCL_CREATED        = BIT(2),
  40        SGX_ENCL_INITIALIZED    = BIT(3),
  41};
  42
  43struct sgx_encl_mm {
  44        struct sgx_encl *encl;
  45        struct mm_struct *mm;
  46        struct list_head list;
  47        struct mmu_notifier mmu_notifier;
  48};
  49
  50struct sgx_encl {
  51        unsigned long base;
  52        unsigned long size;
  53        unsigned long flags;
  54        unsigned int page_cnt;
  55        unsigned int secs_child_cnt;
  56        struct mutex lock;
  57        struct xarray page_array;
  58        struct sgx_encl_page secs;
  59        unsigned long attributes;
  60        unsigned long attributes_mask;
  61
  62        cpumask_t cpumask;
  63        struct file *backing;
  64        struct kref refcount;
  65        struct list_head va_pages;
  66        unsigned long mm_list_version;
  67        struct list_head mm_list;
  68        spinlock_t mm_lock;
  69        struct srcu_struct srcu;
  70};
  71
  72#define SGX_VA_SLOT_COUNT 512
  73
  74struct sgx_va_page {
  75        struct sgx_epc_page *epc_page;
  76        DECLARE_BITMAP(slots, SGX_VA_SLOT_COUNT);
  77        struct list_head list;
  78};
  79
  80struct sgx_backing {
  81        pgoff_t page_index;
  82        struct page *contents;
  83        struct page *pcmd;
  84        unsigned long pcmd_offset;
  85};
  86
  87extern const struct vm_operations_struct sgx_vm_ops;
  88
  89static inline int sgx_encl_find(struct mm_struct *mm, unsigned long addr,
  90                                struct vm_area_struct **vma)
  91{
  92        struct vm_area_struct *result;
  93
  94        result = vma_lookup(mm, addr);
  95        if (!result || result->vm_ops != &sgx_vm_ops)
  96                return -EINVAL;
  97
  98        *vma = result;
  99
 100        return 0;
 101}
 102
 103int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
 104                     unsigned long end, unsigned long vm_flags);
 105
 106void sgx_encl_release(struct kref *ref);
 107int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm);
 108int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
 109                         struct sgx_backing *backing);
 110void sgx_encl_put_backing(struct sgx_backing *backing, bool do_write);
 111int sgx_encl_test_and_clear_young(struct mm_struct *mm,
 112                                  struct sgx_encl_page *page);
 113
 114struct sgx_epc_page *sgx_alloc_va_page(void);
 115unsigned int sgx_alloc_va_slot(struct sgx_va_page *va_page);
 116void sgx_free_va_slot(struct sgx_va_page *va_page, unsigned int offset);
 117bool sgx_va_page_full(struct sgx_va_page *va_page);
 118void sgx_encl_free_epc_page(struct sgx_epc_page *page);
 119
 120#endif /* _X86_ENCL_H */
 121