From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:44710 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727925AbhAVNeM (ORCPT ); Fri, 22 Jan 2021 08:34:12 -0500 Subject: Re: [kvm-unit-tests PATCH v5 1/3] s390x: pv: implement routine to share/unshare memory References: <1611322060-1972-1-git-send-email-pmorel@linux.ibm.com> <1611322060-1972-2-git-send-email-pmorel@linux.ibm.com> From: Janosch Frank Message-ID: <9c488fa9-9b65-ea7f-124e-f9468dc05a54@linux.ibm.com> Date: Fri, 22 Jan 2021 14:33:00 +0100 MIME-Version: 1.0 In-Reply-To: <1611322060-1972-2-git-send-email-pmorel@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit List-ID: To: Pierre Morel , kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, david@redhat.com, thuth@redhat.com, cohuck@redhat.com, imbrenda@linux.ibm.com, drjones@redhat.com, pbonzini@redhat.com On 1/22/21 2:27 PM, Pierre Morel wrote: > When communicating with the host we need to share part of > the memory. > > Let's implement the ultravisor calls for this. Reviewed-by: Janosch Frank > > Signed-off-by: Pierre Morel > Suggested-by: Janosch Frank > Acked-by: Cornelia Huck > Acked-by: Thomas Huth > --- > lib/s390x/asm/uv.h | 39 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 39 insertions(+) > > diff --git a/lib/s390x/asm/uv.h b/lib/s390x/asm/uv.h > index 39d2dc0..9c49184 100644 > --- a/lib/s390x/asm/uv.h > +++ b/lib/s390x/asm/uv.h > @@ -79,4 +79,43 @@ 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 > + }; > + int cc; > + > + cc = uv_call(0, (u64)&uvcb); > + if (!cc && uvcb.header.rc == UVC_RC_EXECUTED) > + return 0; > + > + report_info("uv_call: cmd %04x cc %d response code: %04x", cc, cmd, > + uvcb.header.rc); > + return -1; > +} > + > +/* > + * 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 >