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charset=us-ascii Content-Disposition: inline In-Reply-To: <20230704075054.3344915-3-stevensd@google.com> User-Agent: NeoMutt/20171215 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > @@ -2514,35 +2512,26 @@ static bool hva_to_pfn_fast(unsigned long addr, bool write_fault, > * The slow path to get the pfn of the specified host virtual address, > * 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 interruptible, bool *writable, kvm_pfn_t *pfn) > +static int hva_to_pfn_slow(struct kvm_follow_pfn *foll, kvm_pfn_t *pfn) > { > - unsigned int flags = FOLL_HWPOISON; > + unsigned int flags = FOLL_HWPOISON | FOLL_GET | foll->flags; > struct page *page; > int npages; > > might_sleep(); > > - if (writable) > - *writable = write_fault; > - > - if (write_fault) > - flags |= FOLL_WRITE; > - if (async) > - flags |= FOLL_NOWAIT; > - if (interruptible) > - flags |= FOLL_INTERRUPTIBLE; > - > - npages = get_user_pages_unlocked(addr, 1, &page, flags); > + npages = get_user_pages_unlocked(foll->hva, 1, &page, flags); > if (npages != 1) > return npages; > > + foll->writable = (foll->flags & FOLL_WRITE) && foll->allow_write_mapping; > + > /* map read fault as writable if possible */ > - if (unlikely(!write_fault) && writable) { > + if (unlikely(!foll->writable) && foll->allow_write_mapping) { I guess !foll->writable should be !(foll->flags & FOLL_WRITE) here. > struct page *wpage; > > - if (get_user_page_fast_only(addr, FOLL_WRITE, &wpage)) { > - *writable = true; > + if (get_user_page_fast_only(foll->hva, FOLL_WRITE, &wpage)) { > + foll->writable = true; > put_page(page); > page = wpage; > } > @@ -2572,23 +2561,23 @@ static int kvm_try_get_pfn(kvm_pfn_t pfn) > return get_page_unless_zero(page); > } > ... > +kvm_pfn_t __gfn_to_pfn_memslot(const struct kvm_memory_slot *slot, gfn_t gfn, > + bool atomic, bool interruptible, bool *async, > + bool write_fault, bool *writable, hva_t *hva) > +{ > + kvm_pfn_t pfn; > + struct kvm_follow_pfn foll = { > + .slot = slot, > + .gfn = gfn, > + .flags = 0, > + .atomic = atomic, > + .allow_write_mapping = !!writable, > + }; > + > + if (write_fault) > + foll.flags |= FOLL_WRITE; > + if (async) > + foll.flags |= FOLL_NOWAIT; > + if (interruptible) > + foll.flags |= FOLL_INTERRUPTIBLE; > + > + pfn = __kvm_follow_pfn(&foll); > + if (pfn == KVM_PFN_ERR_NEEDS_IO) { Could we just use KVM_PFN_ERR_FAULT and foll.flags here? I.e., if (pfn == KVM_PFN_ERR_FAULT && (foll.flags & FOLL_NOWAIT))? Setting pfn to KVM_PFN_ERR_NEEDS_IO just to indicate an async fault seems unnecessary. > + *async = true; > + pfn = KVM_PFN_ERR_FAULT; > + } > + if (hva) > + *hva = foll.hva; > + if (writable) > + *writable = foll.writable; > + return pfn; > } > EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot); > B.R. Yu