From patchwork Sun May 16 21:44:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Maciej S. Szmigiero" X-Patchwork-Id: 12260649 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 631E4C433B4 for ; Sun, 16 May 2021 21:45:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3844D61151 for ; Sun, 16 May 2021 21:45:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234239AbhEPVq0 (ORCPT ); Sun, 16 May 2021 17:46:26 -0400 Received: from vps-vb.mhejs.net ([37.28.154.113]:54368 "EHLO vps-vb.mhejs.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229917AbhEPVqY (ORCPT ); Sun, 16 May 2021 17:46:24 -0400 Received: from MUA by vps-vb.mhejs.net with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1liOZ8-0007yt-W7; Sun, 16 May 2021 23:44:51 +0200 From: "Maciej S. Szmigiero" To: Paolo Bonzini , Vitaly Kuznetsov Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Igor Mammedov , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Christian Borntraeger , Janosch Frank , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 2/8] KVM: Integrate gfn_to_memslot_approx() into search_memslots() Date: Sun, 16 May 2021 23:44:28 +0200 Message-Id: X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: "Maciej S. Szmigiero" s390 arch has gfn_to_memslot_approx() which is almost identical to search_memslots(), differing only in that in case the gfn falls in a hole one of the memslots bordering the hole is returned. Add this lookup mode as an option to search_memslots() so we don't have two almost identical functions for looking up a memslot by its gfn. Signed-off-by: Maciej S. Szmigiero --- arch/powerpc/kvm/book3s_64_vio.c | 2 +- arch/powerpc/kvm/book3s_64_vio_hv.c | 2 +- arch/s390/kvm/kvm-s390.c | 39 ++--------------------------- include/linux/kvm_host.h | 13 +++++++--- 4 files changed, 14 insertions(+), 42 deletions(-) diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c index 8da93fdfa59e..148525120504 100644 --- a/arch/powerpc/kvm/book3s_64_vio.c +++ b/arch/powerpc/kvm/book3s_64_vio.c @@ -346,7 +346,7 @@ static long kvmppc_tce_to_ua(struct kvm *kvm, unsigned long tce, unsigned long gfn = tce >> PAGE_SHIFT; struct kvm_memory_slot *memslot; - memslot = search_memslots(kvm_memslots(kvm), gfn); + memslot = search_memslots(kvm_memslots(kvm), gfn, false); if (!memslot) return -EINVAL; diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c index 083a4e037718..a4042403630d 100644 --- a/arch/powerpc/kvm/book3s_64_vio_hv.c +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c @@ -80,7 +80,7 @@ static long kvmppc_rm_tce_to_ua(struct kvm *kvm, unsigned long gfn = tce >> PAGE_SHIFT; struct kvm_memory_slot *memslot; - memslot = search_memslots(kvm_memslots_raw(kvm), gfn); + memslot = search_memslots(kvm_memslots_raw(kvm), gfn, false); if (!memslot) return -EINVAL; diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 1296fc10f80c..75e635ede6ff 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1921,41 +1921,6 @@ static long kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) /* for consistency */ #define KVM_S390_CMMA_SIZE_MAX ((u32)KVM_S390_SKEYS_MAX) -/* - * Similar to gfn_to_memslot, but returns the index of a memslot also when the - * address falls in a hole. In that case the index of one of the memslots - * bordering the hole is returned. - */ -static int gfn_to_memslot_approx(struct kvm_memslots *slots, gfn_t gfn) -{ - int start = 0, end = slots->used_slots; - int slot = atomic_read(&slots->lru_slot); - struct kvm_memory_slot *memslots = slots->memslots; - - if (gfn >= memslots[slot].base_gfn && - gfn < memslots[slot].base_gfn + memslots[slot].npages) - return slot; - - while (start < end) { - slot = start + (end - start) / 2; - - if (gfn >= memslots[slot].base_gfn) - end = slot; - else - start = slot + 1; - } - - if (start >= slots->used_slots) - return slots->used_slots - 1; - - if (gfn >= memslots[start].base_gfn && - gfn < memslots[start].base_gfn + memslots[start].npages) { - atomic_set(&slots->lru_slot, start); - } - - return start; -} - static int kvm_s390_peek_cmma(struct kvm *kvm, struct kvm_s390_cmma_log *args, u8 *res, unsigned long bufsize) { @@ -1982,8 +1947,8 @@ static int kvm_s390_peek_cmma(struct kvm *kvm, struct kvm_s390_cmma_log *args, static unsigned long kvm_s390_next_dirty_cmma(struct kvm_memslots *slots, unsigned long cur_gfn) { - int slotidx = gfn_to_memslot_approx(slots, cur_gfn); - struct kvm_memory_slot *ms = slots->memslots + slotidx; + struct kvm_memory_slot *ms = search_memslots(slots, cur_gfn, true); + int slotidx = ms - slots->memslots; unsigned long ofs = cur_gfn - ms->base_gfn; if (ms->base_gfn + ms->npages <= cur_gfn) { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 8895b95b6a22..3c40c7d32f7e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1091,10 +1091,14 @@ bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args); * gfn_to_memslot() itself isn't here as an inline because that would * bloat other code too much. * + * With "approx" set returns the memslot also when the address falls + * in a hole. In that case one of the memslots bordering the hole is + * returned. + * * IMPORTANT: Slots are sorted from highest GFN to lowest GFN! */ static inline struct kvm_memory_slot * -search_memslots(struct kvm_memslots *slots, gfn_t gfn) +search_memslots(struct kvm_memslots *slots, gfn_t gfn, bool approx) { int start = 0, end = slots->used_slots; int slot = atomic_read(&slots->lru_slot); @@ -1116,19 +1120,22 @@ search_memslots(struct kvm_memslots *slots, gfn_t gfn) start = slot + 1; } + if (approx && start >= slots->used_slots) + return &memslots[slots->used_slots - 1]; + if (start < slots->used_slots && gfn >= memslots[start].base_gfn && gfn < memslots[start].base_gfn + memslots[start].npages) { atomic_set(&slots->lru_slot, start); return &memslots[start]; } - return NULL; + return approx ? &memslots[start] : NULL; } static inline struct kvm_memory_slot * __gfn_to_memslot(struct kvm_memslots *slots, gfn_t gfn) { - return search_memslots(slots, gfn); + return search_memslots(slots, gfn, false); } static inline unsigned long