From patchwork Thu Sep 19 06:02:44 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bharat Bhushan X-Patchwork-Id: 275878 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id EDA902C0290 for ; Thu, 19 Sep 2013 16:13:08 +1000 (EST) Received: from co9outboundpool.messaging.microsoft.com (co9ehsobe005.messaging.microsoft.com [207.46.163.28]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client CN "mail.global.frontbridge.com", Issuer "MSIT Machine Auth CA 2" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 2A84F2C013F for ; Thu, 19 Sep 2013 16:10:43 +1000 (EST) Received: from mail65-co9-R.bigfish.com (10.236.132.239) by CO9EHSOBE001.bigfish.com (10.236.130.64) with Microsoft SMTP Server id 14.1.225.22; Thu, 19 Sep 2013 06:10:39 +0000 Received: from mail65-co9 (localhost [127.0.0.1]) by mail65-co9-R.bigfish.com (Postfix) with ESMTP id BECDC4010F; Thu, 19 Sep 2013 06:10:38 +0000 (UTC) X-Forefront-Antispam-Report: CIP:70.37.183.190; KIP:(null); UIP:(null); IPV:NLI; H:mail.freescale.net; RD:none; EFVD:NLI X-SpamScore: 3 X-BigFish: VS3(zzzz1f42h208ch1ee6h1de0h1fdah2073h1202h1e76h1d1ah1d2ah1fc6h1082kzz1de098h1de097h8275bhz2dh2a8h839he5bhf0ah107ah1288h12a5h12a9h12bdh12e5h137ah139eh13b6h1441h1504h1537h162dh1631h1758h1898h18e1h1946h19b5h1ad9h1b0ah1b2fh1fb3h1d0ch1d2eh1d3fh1dfeh1dffh1e1dh1e23h1fe8h1ff5h1155h) Received: from mail65-co9 (localhost.localdomain [127.0.0.1]) by mail65-co9 (MessageSwitch) id 1379571036495150_13887; Thu, 19 Sep 2013 06:10:36 +0000 (UTC) Received: from CO9EHSMHS015.bigfish.com (unknown [10.236.132.230]) by mail65-co9.bigfish.com (Postfix) with ESMTP id 7298D400050; Thu, 19 Sep 2013 06:10:36 +0000 (UTC) Received: from mail.freescale.net (70.37.183.190) by CO9EHSMHS015.bigfish.com (10.236.130.25) with Microsoft SMTP Server (TLS) id 14.16.227.3; Thu, 19 Sep 2013 06:10:35 +0000 Received: from az84smr01.freescale.net (10.64.34.197) by 039-SN1MMR1-005.039d.mgd.msft.net (10.84.1.17) with Microsoft SMTP Server (TLS) id 14.3.158.2; Thu, 19 Sep 2013 06:10:33 +0000 Received: from freescale.com ([10.232.15.72]) by az84smr01.freescale.net (8.14.3/8.14.0) with SMTP id r8J6ASZU022606; Wed, 18 Sep 2013 23:10:29 -0700 Received: by freescale.com (sSMTP sendmail emulation); Thu, 19 Sep 2013 11:33:11 +0530 From: Bharat Bhushan To: , , , , , , Subject: [PATCH 4/6 v5] kvm: powerpc: keep only pte search logic in lookup_linux_pte Date: Thu, 19 Sep 2013 11:32:44 +0530 Message-ID: <1379570566-3715-5-git-send-email-Bharat.Bhushan@freescale.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <1379570566-3715-1-git-send-email-Bharat.Bhushan@freescale.com> References: <1379570566-3715-1-git-send-email-Bharat.Bhushan@freescale.com> MIME-Version: 1.0 X-OriginatorOrg: freescale.com X-FOPE-CONNECTOR: Id%0$Dn%*$RO%0$TLS%0$FQDN%$TlsDn% Cc: Bharat Bhushan X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.16rc2 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" lookup_linux_pte() was searching for a pte and also sets access flags is writable. This function now searches only pte while access flag setting is done explicitly. This pte lookup is not kvm specific, so moved to common code (asm/pgtable.h) My Followup patch will use this on booke. Signed-off-by: Bharat Bhushan --- v4->v5 - No change arch/powerpc/include/asm/pgtable.h | 24 +++++++++++++++++++++++ arch/powerpc/kvm/book3s_hv_rm_mmu.c | 36 +++++++++++----------------------- 2 files changed, 36 insertions(+), 24 deletions(-) diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 7d6eacf..3a5de5c 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -223,6 +223,30 @@ extern int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr, #endif pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift); + +static inline pte_t *lookup_linux_pte(pgd_t *pgdir, unsigned long hva, + unsigned long *pte_sizep) +{ + pte_t *ptep; + unsigned long ps = *pte_sizep; + unsigned int shift; + + ptep = find_linux_pte_or_hugepte(pgdir, hva, &shift); + if (!ptep) + return __pte(0); + if (shift) + *pte_sizep = 1ul << shift; + else + *pte_sizep = PAGE_SIZE; + + if (ps > *pte_sizep) + return __pte(0); + + if (!pte_present(*ptep)) + return __pte(0); + + return ptep; +} #endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 45e30d6..74fa7f8 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -134,25 +134,6 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index, unlock_rmap(rmap); } -static pte_t lookup_linux_pte(pgd_t *pgdir, unsigned long hva, - int writing, unsigned long *pte_sizep) -{ - pte_t *ptep; - unsigned long ps = *pte_sizep; - unsigned int hugepage_shift; - - ptep = find_linux_pte_or_hugepte(pgdir, hva, &hugepage_shift); - if (!ptep) - return __pte(0); - if (hugepage_shift) - *pte_sizep = 1ul << hugepage_shift; - else - *pte_sizep = PAGE_SIZE; - if (ps > *pte_sizep) - return __pte(0); - return kvmppc_read_update_linux_pte(ptep, writing, hugepage_shift); -} - static inline void unlock_hpte(unsigned long *hpte, unsigned long hpte_v) { asm volatile(PPC_RELEASE_BARRIER "" : : : "memory"); @@ -173,6 +154,7 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags, unsigned long is_io; unsigned long *rmap; pte_t pte; + pte_t *ptep; unsigned int writing; unsigned long mmu_seq; unsigned long rcbits; @@ -231,8 +213,9 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags, /* Look up the Linux PTE for the backing page */ pte_size = psize; - pte = lookup_linux_pte(pgdir, hva, writing, &pte_size); - if (pte_present(pte)) { + ptep = lookup_linux_pte(pgdir, hva, &pte_size); + if (pte_present(pte_val(*ptep))) { + pte = kvmppc_read_update_linux_pte(ptep, writing); if (writing && !pte_write(pte)) /* make the actual HPTE be read-only */ ptel = hpte_make_readonly(ptel); @@ -661,15 +644,20 @@ long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags, struct kvm_memory_slot *memslot; pgd_t *pgdir = vcpu->arch.pgdir; pte_t pte; + pte_t *ptep; psize = hpte_page_size(v, r); gfn = ((r & HPTE_R_RPN) & ~(psize - 1)) >> PAGE_SHIFT; memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn); if (memslot) { hva = __gfn_to_hva_memslot(memslot, gfn); - pte = lookup_linux_pte(pgdir, hva, 1, &psize); - if (pte_present(pte) && !pte_write(pte)) - r = hpte_make_readonly(r); + ptep = lookup_linux_pte(pgdir, hva, &psize); + if (pte_present(pte_val(*ptep))) { + pte = kvmppc_read_update_linux_pte(ptep, + 1); + if (pte_present(pte) && !pte_write(pte)) + r = hpte_make_readonly(r); + } } } }