From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:63210 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2409220AbfJXLmJ (ORCPT ); Thu, 24 Oct 2019 07:42:09 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x9OBbAda020735 for ; Thu, 24 Oct 2019 07:42:08 -0400 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0a-001b2d01.pphosted.com with ESMTP id 2vuabhj5dx-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 24 Oct 2019 07:42:07 -0400 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 24 Oct 2019 12:42:05 +0100 From: Janosch Frank Subject: [RFC 10/37] s390: add (non)secure page access exceptions handlers Date: Thu, 24 Oct 2019 07:40:32 -0400 In-Reply-To: <20191024114059.102802-1-frankja@linux.ibm.com> References: <20191024114059.102802-1-frankja@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: <20191024114059.102802-11-frankja@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, thuth@redhat.com, david@redhat.com, borntraeger@de.ibm.com, imbrenda@linux.ibm.com, mihajlov@linux.ibm.com, mimu@linux.ibm.com, cohuck@redhat.com, gor@linux.ibm.com, frankja@linux.ibm.com From: Vasily Gorbik Add exceptions handlers performing transparent transition of non-secure pages to secure (import) upon guest access and secure pages to non-secure (export) upon hypervisor access. Current assumption is that guest pages are pinned. Signed-off-by: Vasily Gorbik --- arch/s390/kernel/pgm_check.S | 4 +-- arch/s390/mm/fault.c | 64 ++++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+), 2 deletions(-) diff --git a/arch/s390/kernel/pgm_check.S b/arch/s390/kernel/pgm_check.S index 59dee9d3bebf..27ac4f324c70 100644 --- a/arch/s390/kernel/pgm_check.S +++ b/arch/s390/kernel/pgm_check.S @@ -78,8 +78,8 @@ PGM_CHECK(do_dat_exception) /* 39 */ PGM_CHECK(do_dat_exception) /* 3a */ PGM_CHECK(do_dat_exception) /* 3b */ PGM_CHECK_DEFAULT /* 3c */ -PGM_CHECK_DEFAULT /* 3d */ -PGM_CHECK_DEFAULT /* 3e */ +PGM_CHECK(do_secure_storage_access) /* 3d */ +PGM_CHECK(do_non_secure_storage_access) /* 3e */ PGM_CHECK_DEFAULT /* 3f */ PGM_CHECK_DEFAULT /* 40 */ PGM_CHECK_DEFAULT /* 41 */ diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 7b0bb475c166..0c4577472432 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -38,6 +38,7 @@ #include #include #include +#include #include "../kernel/entry.h" #define __FAIL_ADDR_MASK -4096L @@ -816,3 +817,66 @@ static int __init pfault_irq_init(void) early_initcall(pfault_irq_init); #endif /* CONFIG_PFAULT */ + +#ifdef CONFIG_KVM_S390_PROTECTED_VIRTUALIZATION_HOST + +void do_secure_storage_access(struct pt_regs *regs) +{ + unsigned long addr = regs->int_parm_long & __FAIL_ADDR_MASK; + struct vm_area_struct *vma; + struct mm_struct *mm; + struct page *page; + + switch (get_fault_type(regs)) { + case USER_FAULT: + mm = current->mm; + down_read(&mm->mmap_sem); + vma = find_vma(mm, addr); + if (!vma) { + up_read(&mm->mmap_sem); + do_fault_error(regs, VM_READ | VM_WRITE, VM_FAULT_BADMAP); + break; + } + page = follow_page(vma, addr, FOLL_GET); + if (IS_ERR_OR_NULL(page)) { + up_read(&mm->mmap_sem); + break; + } + uv_convert_from_secure(page_to_phys(page)); + put_page(page); + up_read(&mm->mmap_sem); + break; + case KERNEL_FAULT: + uv_convert_from_secure(__pa(addr)); + break; + case VDSO_FAULT: + /* fallthrough */ + case GMAP_FAULT: + /* fallthrough */ + default: + do_fault_error(regs, VM_READ | VM_WRITE, VM_FAULT_BADMAP); + WARN_ON_ONCE(1); + } +} +NOKPROBE_SYMBOL(do_secure_storage_access); + +void do_non_secure_storage_access(struct pt_regs *regs) +{ + unsigned long gaddr = regs->int_parm_long & __FAIL_ADDR_MASK; + struct gmap *gmap = (struct gmap *)S390_lowcore.gmap; + + uv_convert_to_secure(gmap, gaddr); +} +NOKPROBE_SYMBOL(do_non_secure_storage_access); + +#else +void do_secure_storage_access(struct pt_regs *regs) +{ + default_trap_handler(regs); +} + +void do_non_secure_storage_access(struct pt_regs *regs) +{ + default_trap_handler(regs); +} +#endif -- 2.20.1