virt/kvm/kvm_mm.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #ifndef __KVM_MM_H__
   4 #define __KVM_MM_H__ 1
   5
   6 /*
   7  * Architectures can choose whether to use an rwlock or spinlock
   8  * for the mmu_lock.  These macros, for use in common code
   9  * only, avoids using #ifdefs in places that must deal with
  10  * multiple architectures.
  11  */
  12
  13 #ifdef KVM_HAVE_MMU_RWLOCK
  14 #define KVM_MMU_LOCK_INIT(kvm)          rwlock_init(&(kvm)->mmu_lock)
  15 #define KVM_MMU_LOCK(kvm)               write_lock(&(kvm)->mmu_lock)
  16 #define KVM_MMU_UNLOCK(kvm)             write_unlock(&(kvm)->mmu_lock)
  17 #else
  18 #define KVM_MMU_LOCK_INIT(kvm)          spin_lock_init(&(kvm)->mmu_lock)
  19 #define KVM_MMU_LOCK(kvm)               spin_lock(&(kvm)->mmu_lock)
  20 #define KVM_MMU_UNLOCK(kvm)             spin_unlock(&(kvm)->mmu_lock)
  21 #endif /* KVM_HAVE_MMU_RWLOCK */
  22
  23
  24 struct kvm_follow_pfn {
  25         const struct kvm_memory_slot *slot;
  26         const gfn_t gfn;
  27
  28         unsigned long hva;
  29
  30         /* FOLL_* flags modifying lookup behavior, e.g. FOLL_WRITE. */
  31         unsigned int flags;
  32
  33         /*
  34          * Pin the page (effectively FOLL_PIN, which is an mm/ internal flag).
  35          * The page *must* be pinned if KVM will write to the page via a kernel
  36          * mapping, e.g. via kmap(), mremap(), etc.
  37          */
  38         bool pin;
  39
  40         /*
  41          * If non-NULL, try to get a writable mapping even for a read fault.
  42          * Set to true if a writable mapping was obtained.
  43          */
  44         bool *map_writable;
  45
  46         /*
  47          * Optional output.  Set to a valid "struct page" if the returned pfn
  48          * is for a refcounted or pinned struct page, NULL if the returned pfn
  49          * has no struct page or if the struct page is not being refcounted
  50          * (e.g. tail pages of non-compound higher order allocations from
  51          * IO/PFNMAP mappings).
  52          */
  53         struct page **refcounted_page;
  54 };
  55
  56 kvm_pfn_t hva_to_pfn(struct kvm_follow_pfn *kfp);
  57
  58 #ifdef CONFIG_HAVE_KVM_PFNCACHE
  59 void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm,
  60                                        unsigned long start,
  61                                        unsigned long end);
  62 #else
  63 static inline void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm,
  64                                                      unsigned long start,
  65                                                      unsigned long end)
  66 {
  67 }
  68 #endif /* HAVE_KVM_PFNCACHE */
  69
  70 #ifdef CONFIG_KVM_PRIVATE_MEM
  71 void kvm_gmem_init(struct module *module);
  72 int kvm_gmem_create(struct kvm *kvm, struct kvm_create_guest_memfd *args);
  73 int kvm_gmem_bind(struct kvm *kvm, struct kvm_memory_slot *slot,
  74                   unsigned int fd, loff_t offset);
  75 void kvm_gmem_unbind(struct kvm_memory_slot *slot);
  76 #else
  77 static inline void kvm_gmem_init(struct module *module)
  78 {
  79
  80 }
  81
  82 static inline int kvm_gmem_bind(struct kvm *kvm,
  83                                          struct kvm_memory_slot *slot,
  84                                          unsigned int fd, loff_t offset)
  85 {
  86         WARN_ON_ONCE(1);
  87         return -EIO;
  88 }
  89
  90 static inline void kvm_gmem_unbind(struct kvm_memory_slot *slot)
  91 {
  92         WARN_ON_ONCE(1);
  93 }
  94 #endif /* CONFIG_KVM_PRIVATE_MEM */
  95
  96 #endif /* __KVM_MM_H__ */