[PATCH 2/6] KVM: mmu: also return page from gfn_to_pfn

From: David Stevens stevensd@chromium.org

Return a struct kvm_pfn_page containing both a pfn and an optional struct page from the gfn_to_pfn family of functions. This differentiates the gup and follow_fault_pfn cases, which allows callers that only need a pfn to avoid touching the page struct in the latter case. For callers that need a struct page, introduce a helper function that unwraps a struct kvm_pfn_page into a struct page. This helper makes the call to kvm_get_pfn which had previously been in hva_to_pfn_remapped.

For now, wrap all calls to gfn_to_pfn functions in the new helper function. Callers which don't need the page struct will be updated in follow-up patches.

Signed-off-by: David Stevens stevensd@chromium.org --- arch/arm64/kvm/mmu.c | 5 +- arch/mips/kvm/mmu.c | 3 +- arch/powerpc/kvm/book3s.c | 3 +- arch/powerpc/kvm/book3s_64_mmu_hv.c | 5 +- arch/powerpc/kvm/book3s_64_mmu_radix.c | 5 +- arch/powerpc/kvm/book3s_hv_uvmem.c | 4 +- arch/powerpc/kvm/e500_mmu_host.c | 2 +- arch/x86/kvm/mmu/mmu.c | 11 ++- arch/x86/kvm/mmu/mmu_audit.c | 2 +- arch/x86/kvm/x86.c | 2 +- drivers/gpu/drm/i915/gvt/kvmgt.c | 2 +- include/linux/kvm_host.h | 27 ++++-- include/linux/kvm_types.h | 5 + virt/kvm/kvm_main.c | 121 +++++++++++++------------ 14 files changed, 109 insertions(+), 88 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index c10207fed2f3..896b3644b36f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -933,8 +933,9 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, */ smp_rmb();

- pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, - write_fault, &writable, NULL); + pfn = kvm_pfn_page_unwrap(__gfn_to_pfn_memslot(memslot, gfn, false, + NULL, write_fault, + &writable, NULL)); if (pfn == KVM_PFN_ERR_HWPOISON) { kvm_send_hwpoison_signal(hva, vma_shift); return 0; diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c index 6d1f68cf4edf..f4e5e48bc6bf 100644 --- a/arch/mips/kvm/mmu.c +++ b/arch/mips/kvm/mmu.c @@ -630,7 +630,8 @@ static int kvm_mips_map_page(struct kvm_vcpu *vcpu, unsigned long gpa, smp_rmb();

/* Slow path - ask KVM core whether we can access this GPA */ - pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writeable); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn_prot(kvm, gfn, + write_fault, &writeable)); if (is_error_noslot_pfn(pfn)) { err = -EFAULT; goto out; diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index 2b691f4d1f26..2dff01d0632a 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -417,7 +417,8 @@ kvm_pfn_t kvmppc_gpa_to_pfn(struct kvm_vcpu *vcpu, gpa_t gpa, bool writing, return pfn; }

- return gfn_to_pfn_prot(vcpu->kvm, gfn, writing, writable); + return kvm_pfn_page_unwrap(gfn_to_pfn_prot(vcpu->kvm, gfn, + writing, writable)); } EXPORT_SYMBOL_GPL(kvmppc_gpa_to_pfn);

diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 2d9193cd73be..ba094b9f87a9 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -590,8 +590,9 @@ int kvmppc_book3s_hv_page_fault(struct kvm_vcpu *vcpu, write_ok = true; } else { /* Call KVM generic code to do the slow-path check */ - pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, - writing, &write_ok, NULL); + pfn = kvm_pfn_page_unwrap( + __gfn_to_pfn_memslot(memslot, gfn, false, NULL, + writing, &write_ok, NULL)); if (is_error_noslot_pfn(pfn)) return -EFAULT; page = NULL; diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index d909c069363e..e7892f148222 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -821,8 +821,9 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, unsigned long pfn;

/* Call KVM generic code to do the slow-path check */ - pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, - writing, upgrade_p, NULL); + pfn = kvm_pfn_page_unwrap( + __gfn_to_pfn_memslot(memslot, gfn, false, NULL, + writing, upgrade_p, NULL)); if (is_error_noslot_pfn(pfn)) return -EFAULT; page = NULL; diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c index 84e5a2dc8be5..0eee0d98b055 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -890,7 +890,7 @@ static unsigned long kvmppc_share_page(struct kvm *kvm, unsigned long gpa,

retry: mutex_unlock(&kvm->arch.uvmem_lock); - pfn = gfn_to_pfn(kvm, gfn); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn(kvm, gfn)); if (is_error_noslot_pfn(pfn)) goto out;

@@ -1075,7 +1075,7 @@ int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gfn) unsigned long pfn; int ret = U_SUCCESS;

- pfn = gfn_to_pfn(kvm, gfn); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn(kvm, gfn)); if (is_error_noslot_pfn(pfn)) return -EFAULT;

diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c index 7f16afc331ef..be7ca5788a05 100644 --- a/arch/powerpc/kvm/e500_mmu_host.c +++ b/arch/powerpc/kvm/e500_mmu_host.c @@ -446,7 +446,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,

if (likely(!pfnmap)) { tsize_pages = 1UL << (tsize + 10 - PAGE_SHIFT); - pfn = gfn_to_pfn_memslot(slot, gfn); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn_memslot(slot, gfn)); if (is_error_noslot_pfn(pfn)) { if (printk_ratelimit()) pr_err("%s: real page not found for gfn %lx\n", diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 8d5876dfc6b7..84913677c404 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -2619,7 +2619,7 @@ static kvm_pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, if (!slot) return KVM_PFN_ERR_FAULT;

- return gfn_to_pfn_memslot_atomic(slot, gfn); + return kvm_pfn_page_unwrap(gfn_to_pfn_memslot_atomic(slot, gfn)); }

static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, @@ -3694,8 +3694,9 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, }

async = false; - *pfn = __gfn_to_pfn_memslot(slot, gfn, false, &async, - write, writable, hva); + *pfn = kvm_pfn_page_unwrap(__gfn_to_pfn_memslot(slot, gfn, false, + &async, write, + writable, hva)); if (!async) return false; /* *pfn has correct page already */

@@ -3709,8 +3710,8 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, return true; }

- *pfn = __gfn_to_pfn_memslot(slot, gfn, false, NULL, - write, writable, hva); + *pfn = kvm_pfn_page_unwrap(__gfn_to_pfn_memslot(slot, gfn, false, NULL, + write, writable, hva)); return false; }

diff --git a/arch/x86/kvm/mmu/mmu_audit.c b/arch/x86/kvm/mmu/mmu_audit.c index 97ff184084b4..3f983dc6e0f1 100644 --- a/arch/x86/kvm/mmu/mmu_audit.c +++ b/arch/x86/kvm/mmu/mmu_audit.c @@ -111,7 +111,7 @@ static void audit_mappings(struct kvm_vcpu *vcpu, u64 *sptep, int level) return;

gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); - pfn = kvm_vcpu_gfn_to_pfn_atomic(vcpu, gfn); + pfn = kvm_pfn_page_unwrap(kvm_vcpu_gfn_to_pfn_atomic(vcpu, gfn));

if (is_error_pfn(pfn)) return; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6d425310054b..d31797e0cb6e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7341,7 +7341,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, * retry instruction -> write #PF -> emulation fail -> retry * instruction -> ... */ - pfn = gfn_to_pfn(vcpu->kvm, gpa_to_gfn(gpa)); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn(vcpu->kvm, gpa_to_gfn(gpa)));

/* * If the instruction failed on the error pfn, it can not be fixed, diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index 65ff43cfc0f7..b829ff67e3d9 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -1938,7 +1938,7 @@ static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn)

info = (struct kvmgt_guest_info *)handle;

- pfn = gfn_to_pfn(info->kvm, gfn); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn(info->kvm, gfn)); if (is_error_noslot_pfn(pfn)) return INTEL_GVT_INVALID_ADDR;

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 8583ed3ff344..d3731790a967 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -138,6 +138,8 @@ static inline bool is_error_page(struct page *page) return IS_ERR(page); }

+#define KVM_PFN_PAGE_ERR(e) ((struct kvm_pfn_page) { .pfn = (e), .page = NULL }) + #define KVM_REQUEST_MASK GENMASK(7,0) #define KVM_REQUEST_NO_WAKEUP BIT(8) #define KVM_REQUEST_WAIT BIT(9) @@ -795,14 +797,19 @@ void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page); void kvm_set_page_accessed(struct page *page);

-kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn); -kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, - bool *writable); -kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn); -kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn); -kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, - bool atomic, bool *async, bool write_fault, - bool *writable, hva_t *hva); +struct kvm_pfn_page gfn_to_pfn(struct kvm *kvm, gfn_t gfn); +struct kvm_pfn_page gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, + bool write_fault, bool *writable); +struct kvm_pfn_page gfn_to_pfn_memslot(struct kvm_memory_slot *slot, + gfn_t gfn); +struct kvm_pfn_page gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, + gfn_t gfn); +struct kvm_pfn_page __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, + gfn_t gfn, bool atomic, bool *async, + bool write_fault, bool *writable, + hva_t *hva); + +kvm_pfn_t kvm_pfn_page_unwrap(struct kvm_pfn_page pfnpg);

void kvm_release_pfn_clean(kvm_pfn_t pfn); void kvm_release_pfn_dirty(kvm_pfn_t pfn); @@ -883,8 +890,8 @@ void mark_page_dirty(struct kvm *kvm, gfn_t gfn);

struct kvm_memslots *kvm_vcpu_memslots(struct kvm_vcpu *vcpu); struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn); -kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn); -kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn); +struct kvm_pfn_page kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn); +struct kvm_pfn_page kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn); int kvm_vcpu_map(struct kvm_vcpu *vcpu, gpa_t gpa, struct kvm_host_map *map); int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map, struct gfn_to_pfn_cache *cache, bool atomic); diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h index a7580f69dda0..471f4b329f46 100644 --- a/include/linux/kvm_types.h +++ b/include/linux/kvm_types.h @@ -45,6 +45,11 @@ typedef u64 hfn_t;

typedef hfn_t kvm_pfn_t;

+struct kvm_pfn_page { + kvm_pfn_t pfn; + struct page *page; +}; + struct gfn_to_hva_cache { u64 generation; gpa_t gpa; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6a6bc7af0e28..898e90be4d0e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1982,9 +1982,8 @@ static inline int check_user_page_hwpoison(unsigned long addr) * only part that runs if we can in atomic context. */ static bool hva_to_pfn_fast(unsigned long addr, bool write_fault, - bool *writable, kvm_pfn_t *pfn) + bool *writable, struct kvm_pfn_page *pfnpg) { - struct page *page[1];

/* * Fast pin a writable pfn only if it is a write fault request @@ -1994,8 +1993,8 @@ static bool hva_to_pfn_fast(unsigned long addr, bool write_fault, if (!(write_fault || writable)) return false;

- if (get_user_page_fast_only(addr, FOLL_WRITE, page)) { - *pfn = page_to_pfn(page[0]); + if (get_user_page_fast_only(addr, FOLL_WRITE, &pfnpg->page)) { + pfnpg->pfn = page_to_pfn(pfnpg->page);

if (writable) *writable = true; @@ -2010,10 +2009,9 @@ static bool hva_to_pfn_fast(unsigned long addr, bool write_fault, * 1 indicates success, -errno is returned if error is detected. */ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, - bool *writable, kvm_pfn_t *pfn) + bool *writable, struct kvm_pfn_page *pfnpg) { unsigned int flags = FOLL_HWPOISON; - struct page *page; int npages = 0;

might_sleep(); @@ -2026,7 +2024,7 @@ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, if (async) flags |= FOLL_NOWAIT;

- npages = get_user_pages_unlocked(addr, 1, &page, flags); + npages = get_user_pages_unlocked(addr, 1, &pfnpg->page, flags); if (npages != 1) return npages;

@@ -2036,11 +2034,11 @@ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,

if (get_user_page_fast_only(addr, FOLL_WRITE, &wpage)) { *writable = true; - put_page(page); - page = wpage; + put_page(pfnpg->page); + pfnpg->page = wpage; } } - *pfn = page_to_pfn(page); + pfnpg->pfn = page_to_pfn(pfnpg->page); return npages; }

@@ -2058,7 +2056,7 @@ static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault) static int hva_to_pfn_remapped(struct vm_area_struct *vma, unsigned long addr, bool *async, bool write_fault, bool *writable, - kvm_pfn_t *p_pfn) + struct kvm_pfn_page *p_pfn) { kvm_pfn_t pfn; pte_t *ptep; @@ -2094,22 +2092,12 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma, *writable = pte_write(*ptep); pfn = pte_pfn(*ptep);

- /* - * Get a reference here because callers of *hva_to_pfn* and - * *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the - * returned pfn. This is only needed if the VMA has VM_MIXEDMAP - * set, but the kvm_get_pfn/kvm_release_pfn_clean pair will - * simply do nothing for reserved pfns. - * - * Whoever called remap_pfn_range is also going to call e.g. - * unmap_mapping_range before the underlying pages are freed, - * causing a call to our MMU notifier. - */ - kvm_get_pfn(pfn); - out: pte_unmap_unlock(ptep, ptl); - *p_pfn = pfn; + + p_pfn->pfn = pfn; + p_pfn->page = NULL; + return 0; }

@@ -2127,30 +2115,30 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma, * 2): @write_fault = false && @writable, @writable will tell the caller * whether the mapping is writable. */ -static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, - bool write_fault, bool *writable) +static struct kvm_pfn_page hva_to_pfn(unsigned long addr, bool atomic, + bool *async, bool write_fault, bool *writable) { struct vm_area_struct *vma; - kvm_pfn_t pfn = 0; + struct kvm_pfn_page pfnpg = {}; int npages, r;

/* we can do it either atomically or asynchronously, not both */ BUG_ON(atomic && async);

- if (hva_to_pfn_fast(addr, write_fault, writable, &pfn)) - return pfn; + if (hva_to_pfn_fast(addr, write_fault, writable, &pfnpg)) + return pfnpg;

if (atomic) - return KVM_PFN_ERR_FAULT; + return KVM_PFN_PAGE_ERR(KVM_PFN_ERR_FAULT);

- npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn); + npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfnpg); if (npages == 1) - return pfn; + return pfnpg;

mmap_read_lock(current->mm); if (npages == -EHWPOISON || (!async && check_user_page_hwpoison(addr))) { - pfn = KVM_PFN_ERR_HWPOISON; + pfnpg.pfn = KVM_PFN_ERR_HWPOISON; goto exit; }

@@ -2158,26 +2146,27 @@ static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, vma = find_vma_intersection(current->mm, addr, addr + 1);

if (vma == NULL) - pfn = KVM_PFN_ERR_FAULT; + pfnpg.pfn = KVM_PFN_ERR_FAULT; else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) { - r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfn); + r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfnpg); if (r == -EAGAIN) goto retry; if (r < 0) - pfn = KVM_PFN_ERR_FAULT; + pfnpg.pfn = KVM_PFN_ERR_FAULT; } else { if (async && vma_is_valid(vma, write_fault)) *async = true; - pfn = KVM_PFN_ERR_FAULT; + pfnpg.pfn = KVM_PFN_ERR_FAULT; } exit: mmap_read_unlock(current->mm); - return pfn; + return pfnpg; }

-kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, - bool atomic, bool *async, bool write_fault, - bool *writable, hva_t *hva) +struct kvm_pfn_page __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, + gfn_t gfn, bool atomic, bool *async, + bool write_fault, bool *writable, + hva_t *hva) { unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);

@@ -2187,13 +2176,13 @@ kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, if (addr == KVM_HVA_ERR_RO_BAD) { if (writable) *writable = false; - return KVM_PFN_ERR_RO_FAULT; + return KVM_PFN_PAGE_ERR(KVM_PFN_ERR_RO_FAULT); }

if (kvm_is_error_hva(addr)) { if (writable) *writable = false; - return KVM_PFN_NOSLOT; + return KVM_PFN_PAGE_ERR(KVM_PFN_NOSLOT); }

/* Do not map writable pfn in the readonly memslot. */ @@ -2207,44 +2196,55 @@ kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, } EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);

-kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, - bool *writable) +struct kvm_pfn_page gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, + bool write_fault, bool *writable) { return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL, write_fault, writable, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);

-kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn) +struct kvm_pfn_page gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn) { return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);

-kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn) +struct kvm_pfn_page gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, + gfn_t gfn) { return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);

-kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn) +struct kvm_pfn_page kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn) { return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn); } EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);

-kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn) +struct kvm_pfn_page gfn_to_pfn(struct kvm *kvm, gfn_t gfn) { return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn); } EXPORT_SYMBOL_GPL(gfn_to_pfn);

-kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn) +struct kvm_pfn_page kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn) { return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn); } EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);

+kvm_pfn_t kvm_pfn_page_unwrap(struct kvm_pfn_page pfnpg) +{ + if (pfnpg.page) + return pfnpg.pfn; + + kvm_get_pfn(pfnpg.pfn); + return pfnpg.pfn; +} +EXPORT_SYMBOL_GPL(kvm_pfn_page_unwrap); + int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn, struct page **pages, int nr_pages) { @@ -2277,11 +2277,14 @@ static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)

struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) { - kvm_pfn_t pfn; + struct kvm_pfn_page pfnpg; + + pfnpg = gfn_to_pfn(kvm, gfn);

- pfn = gfn_to_pfn(kvm, gfn); + if (pfnpg.page) + return pfnpg.page;

- return kvm_pfn_to_page(pfn); + return kvm_pfn_to_page(kvm_pfn_page_unwrap(pfnpg)); } EXPORT_SYMBOL_GPL(gfn_to_page);

@@ -2304,7 +2307,7 @@ static void kvm_cache_gfn_to_pfn(struct kvm_memory_slot *slot, gfn_t gfn, { kvm_release_pfn(cache->pfn, cache->dirty, cache);

- cache->pfn = gfn_to_pfn_memslot(slot, gfn); + cache->pfn = kvm_pfn_page_unwrap(gfn_to_pfn_memslot(slot, gfn)); cache->gfn = gfn; cache->dirty = false; cache->generation = gen; @@ -2335,7 +2338,7 @@ static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn, } else { if (atomic) return -EAGAIN; - pfn = gfn_to_pfn_memslot(slot, gfn); + pfn = kvm_pfn_page_unwrap(gfn_to_pfn_memslot(slot, gfn)); } if (is_error_noslot_pfn(pfn)) return -EINVAL; @@ -2435,11 +2438,11 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_unmap);

struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn) { - kvm_pfn_t pfn; + struct kvm_pfn_page pfnpg;

- pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn); + pfnpg = kvm_vcpu_gfn_to_pfn(vcpu, gfn);

- return kvm_pfn_to_page(pfn); + return kvm_pfn_to_page(kvm_pfn_page_unwrap(pfnpg)); } EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page);