Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752722Ab0G0RUu (ORCPT ); Tue, 27 Jul 2010 13:20:50 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:36710 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752683Ab0G0RUp (ORCPT >); Tue, 27 Jul 2010 13:20:45 -0400 From: Konrad Rzeszutek Wilk To: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Cc: Jeremy Fitzhardinge , alex.williamson@redhat.com, Jeremy Fitzhardinge , Konrad Rzeszutek Wilk Subject: [PATCH 1/9] xen: use _PAGE_IOMAP in ioremap to do machine mappings Date: Tue, 27 Jul 2010 12:59:54 -0400 Message-Id: <1280250002-20279-2-git-send-email-konrad.wilk@oracle.com> X-Mailer: git-send-email 1.7.0.1 In-Reply-To: <1280250002-20279-1-git-send-email-konrad.wilk@oracle.com> References: <1280250002-20279-1-git-send-email-konrad.wilk@oracle.com> X-Source-IP: acsmt353.oracle.com [141.146.40.153] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090204.4C4F153B.003C:SCFMA4539814,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5159 Lines: 181 From: Jeremy Fitzhardinge In a Xen domain, ioremap operates on machine addresses, not pseudo-physical addresses. We use _PAGE_IOMAP to determine whether a mapping is intended for machine addresses. [ Impact: allow Xen domain to map real hardware ] Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/include/asm/xen/page.h | 8 +--- arch/x86/xen/mmu.c | 71 +++++++++++++++++++++++++++++++++++++- 2 files changed, 71 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 018a0a4..bf5f7d3 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -112,13 +112,9 @@ static inline xpaddr_t machine_to_phys(xmaddr_t machine) */ static inline unsigned long mfn_to_local_pfn(unsigned long mfn) { - extern unsigned long max_mapnr; unsigned long pfn = mfn_to_pfn(mfn); - if ((pfn < max_mapnr) - && !xen_feature(XENFEAT_auto_translated_physmap) - && (get_phys_to_machine(pfn) != mfn)) - return max_mapnr; /* force !pfn_valid() */ - /* XXX fixme; not true with sparsemem */ + if (get_phys_to_machine(pfn) != mfn) + return -1; /* force !pfn_valid() */ return pfn; } diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 914f046..a4dea9d 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -56,9 +56,11 @@ #include #include +#include #include #include #include +#include #include #include "multicalls.h" @@ -377,6 +379,28 @@ static bool xen_page_pinned(void *ptr) return PagePinned(page); } +static bool xen_iomap_pte(pte_t pte) +{ + return xen_initial_domain() && (pte_flags(pte) & _PAGE_IOMAP); +} + +static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval) +{ + struct multicall_space mcs; + struct mmu_update *u; + + mcs = xen_mc_entry(sizeof(*u)); + u = mcs.args; + + /* ptep might be kmapped when using 32-bit HIGHPTE */ + u->ptr = arbitrary_virt_to_machine(ptep).maddr; + u->val = pte_val_ma(pteval); + + MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, DOMID_IO); + + xen_mc_issue(PARAVIRT_LAZY_MMU); +} + static void xen_extend_mmu_update(const struct mmu_update *update) { struct multicall_space mcs; @@ -453,6 +477,11 @@ void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags) void xen_set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval) { + if (xen_iomap_pte(pteval)) { + xen_set_iomap_pte(ptep, pteval); + goto out; + } + ADD_STATS(set_pte_at, 1); // ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep)); ADD_STATS(set_pte_at_current, mm == current->mm); @@ -523,8 +552,25 @@ static pteval_t pte_pfn_to_mfn(pteval_t val) return val; } +static pteval_t iomap_pte(pteval_t val) +{ + if (val & _PAGE_PRESENT) { + unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT; + pteval_t flags = val & PTE_FLAGS_MASK; + + /* We assume the pte frame number is a MFN, so + just use it as-is. */ + val = ((pteval_t)pfn << PAGE_SHIFT) | flags; + } + + return val; +} + pteval_t xen_pte_val(pte_t pte) { + if (xen_initial_domain() && (pte.pte & _PAGE_IOMAP)) + return pte.pte; + return pte_mfn_to_pfn(pte.pte); } PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val); @@ -537,7 +583,11 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val); pte_t xen_make_pte(pteval_t pte) { - pte = pte_pfn_to_mfn(pte); + if (unlikely(xen_initial_domain() && (pte & _PAGE_IOMAP))) + pte = iomap_pte(pte); + else + pte = pte_pfn_to_mfn(pte); + return native_make_pte(pte); } PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte); @@ -593,6 +643,11 @@ void xen_set_pud(pud_t *ptr, pud_t val) void xen_set_pte(pte_t *ptep, pte_t pte) { + if (xen_iomap_pte(pte)) { + xen_set_iomap_pte(ptep, pte); + return; + } + ADD_STATS(pte_update, 1); // ADD_STATS(pte_update_pinned, xen_page_pinned(ptep)); ADD_STATS(pte_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU); @@ -609,6 +664,11 @@ void xen_set_pte(pte_t *ptep, pte_t pte) #ifdef CONFIG_X86_PAE void xen_set_pte_atomic(pte_t *ptep, pte_t pte) { + if (xen_iomap_pte(pte)) { + xen_set_iomap_pte(ptep, pte); + return; + } + set_64bit((u64 *)ptep, native_pte_val(pte)); } @@ -1811,9 +1871,16 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) pte = pfn_pte(phys, prot); break; - default: + case FIX_PARAVIRT_BOOTMAP: + /* This is an MFN, but it isn't an IO mapping from the + IO domain */ pte = mfn_pte(phys, prot); break; + + default: + /* By default, set_fixmap is used for hardware mappings */ + pte = mfn_pte(phys, __pgprot(pgprot_val(prot) | _PAGE_IOMAP)); + break; } __native_set_fixmap(idx, pte); -- 1.7.0.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/