From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:43550 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729125AbgIYQjB (ORCPT ); Fri, 25 Sep 2020 12:39:01 -0400 From: Pierre Morel Subject: [PATCH v1 3/4] s390: define UV compatible I/O allocation Date: Fri, 25 Sep 2020 18:02:43 +0200 Message-Id: <1601049764-11784-4-git-send-email-pmorel@linux.ibm.com> In-Reply-To: <1601049764-11784-1-git-send-email-pmorel@linux.ibm.com> References: <1601049764-11784-1-git-send-email-pmorel@linux.ibm.com> List-ID: To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, thuth@redhat.com, cohuck@redhat.com, imbrenda@linux.ibm.com To centralize the memory allocation for I/O we define the alloc/free_io_page() functions which share the I/O memory with the host in case the guest runs with protected virtualization. Signed-off-by: Pierre Morel --- lib/s390x/malloc_io.c | 50 +++++++++++++++++++++++++++++++++++++++++++ lib/s390x/malloc_io.h | 18 ++++++++++++++++ s390x/Makefile | 1 + 3 files changed, 69 insertions(+) create mode 100644 lib/s390x/malloc_io.c create mode 100644 lib/s390x/malloc_io.h diff --git a/lib/s390x/malloc_io.c b/lib/s390x/malloc_io.c new file mode 100644 index 0000000..b84a06a --- /dev/null +++ b/lib/s390x/malloc_io.c @@ -0,0 +1,50 @@ +/* + * I/O page allocation + * + * Copyright (c) 2020 IBM Corp + * + * Authors: + * Pierre Morel + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2. + * + * Using this interface provide host access to the allocated pages in + * case the guest is a secure guest. + * This is needed for I/O buffers. + * + */ +#include +#include +#include +#include +#include + +void *alloc_io_page(int size) +{ + void *p; + + assert(size <= PAGE_SIZE); + p = get_dma_page(); + if (!p) { + report(0, "Memory allocation"); + return NULL; + } + + if (!test_facility(158)) + return p; + + if (!uv_set_shared((unsigned long)p)) { + report(0, "Sharing memory"); + return NULL; + } + + return p; +} + +void free_io_page(void *p) +{ + if (test_facility(158) && !uv_remove_shared((unsigned long)p)) + report(0, "Unsharing memory"); + put_dma_page(p); +} diff --git a/lib/s390x/malloc_io.h b/lib/s390x/malloc_io.h new file mode 100644 index 0000000..c6ed481 --- /dev/null +++ b/lib/s390x/malloc_io.h @@ -0,0 +1,18 @@ +/* + * I/O allocations + * + * Copyright (c) 2020 IBM Corp + * + * Authors: + * Pierre Morel + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2. + */ +#ifndef _S390X_MALLOC_IO_H_ +#define _S390X_MALLOC_IO_H_ + +void *alloc_io_page(int size); +void free_io_page(void *p); + +#endif /* _S390X_MALLOC_IO_H_ */ diff --git a/s390x/Makefile b/s390x/Makefile index 109ef9f..1b1dc9f 100644 --- a/s390x/Makefile +++ b/s390x/Makefile @@ -63,6 +63,7 @@ cflatobjs += lib/s390x/smp.o cflatobjs += lib/s390x/vm.o cflatobjs += lib/s390x/css_dump.o cflatobjs += lib/s390x/css_lib.o +cflatobjs += lib/s390x/malloc_io.o OBJDIRS += lib/s390x -- 2.25.1