From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:23160 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728148AbgIYQDO (ORCPT ); Fri, 25 Sep 2020 12:03:14 -0400 From: Pierre Morel Subject: [PATCH v1 2/4] s390x: pv: implement routine to share/unshare memory Date: Fri, 25 Sep 2020 18:02:42 +0200 Message-Id: <1601049764-11784-3-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 When communicating with the host we need to share part of the memory. Let's implement the ultravisor calls for this. Signed-off-by: Pierre Morel Suggested-by: Janosch Frank --- lib/s390x/asm/uv.h | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/lib/s390x/asm/uv.h b/lib/s390x/asm/uv.h index 4c2fc48..19019e4 100644 --- a/lib/s390x/asm/uv.h +++ b/lib/s390x/asm/uv.h @@ -71,4 +71,37 @@ static inline int uv_call(unsigned long r1, unsigned long r2) return cc; } +static inline int share(unsigned long addr, u16 cmd) +{ + struct uv_cb_share uvcb = { + .header.cmd = cmd, + .header.len = sizeof(uvcb), + .paddr = addr + }; + + uv_call(0, (u64)&uvcb); + return uvcb.header.rc; +} + +/* + * Guest 2 request to the Ultravisor to make a page shared with the + * hypervisor for IO. + * + * @addr: Real or absolute address of the page to be shared + */ +static inline int uv_set_shared(unsigned long addr) +{ + return share(addr, UVC_CMD_SET_SHARED_ACCESS); +} + +/* + * Guest 2 request to the Ultravisor to make a page unshared. + * + * @addr: Real or absolute address of the page to be unshared + */ +static inline int uv_remove_shared(unsigned long addr) +{ + return share(addr, UVC_CMD_REMOVE_SHARED_ACCESS); +} + #endif -- 2.25.1