From patchwork Mon Feb 10 06:02:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 11372501 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2AD6C92A for ; Mon, 10 Feb 2020 06:03:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0038724680 for ; Mon, 10 Feb 2020 06:03:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581314596; bh=JKAs/yk3oebL2JJu+bJ0fqXfQJ/mghBaRgtB5NbwWAc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SfZDjOEerEx2QC1ideInLLvt7Lft0zTyGbu9UaZH3cnLBkbed0ksPZe6CoA0VOES+ cVgTbwemDpA/7xyM1xv+74VFNXvlLjxUNQ/ZO12iJu2+8xoim68he/jxqrjGK9z9cq 8F33AN2ImaZqksTv+CZpriIclI3eT2SGq0HHsfdw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727577AbgBJGDP (ORCPT ); Mon, 10 Feb 2020 01:03:15 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:36352 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727530AbgBJGDM (ORCPT ); Mon, 10 Feb 2020 01:03:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=PCOYorxp5B66Bz7dLpdri3RiULamlM3oIiU8p4XbyRM=; b=CwID2ypUiVS4KSCL4PaxfFZG8z PvMuFFKerubiFW4Gfiu0rdhLZ5JqtvUzsmOzivZrLW9IapSUfKzHi5djXqYEkrAxGP8maRzVhAHYW b3ao5ZqbLQ+0nZKDVfgoshwwz9+If0pGQKT31lEOKPyY9xrt3IIrH07fG9FVci1bJr/BkQJ4WDRpK Tv3xCjD0KItoP/Ao6tfwFmDO+weMvKdpgCnTqUzFcEU96yfl1dNhX/qPysBpxpl71Y0wq/6RvJ630 Tbml4Ro6Su8BoUbqZyJwVJpgEVvfLPlG+4XPupJ3Khy6kyjD5XgHL3MhCP6EVXpSPgZyY2qSReY5O BxFYx4OQ==; Received: from [80.156.29.194] (helo=bombadil.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1j12A4-0006Tu-5J; Mon, 10 Feb 2020 06:03:12 +0000 Received: from mchehab by bombadil.infradead.org with local (Exim 4.92.3) (envelope-from ) id 1j12A2-00C2WA-El; Mon, 10 Feb 2020 07:03:10 +0100 From: Mauro Carvalho Chehab To: Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , Paolo Bonzini , Jonathan Corbet , kvm@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH 20/28] docs: kvm: Convert hypercalls.txt to ReST format Date: Mon, 10 Feb 2020 07:02:58 +0100 Message-Id: <48904ada2b9d61f513fc081358cbc4406926c999.1581314317.git.mchehab+huawei@kernel.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: References: MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org - Use document title and chapter markups; - Convert tables; - Add markups for literal blocks; - use :field: for field descriptions; - Add blank lines and adjust indentation Signed-off-by: Mauro Carvalho Chehab --- .../kvm/{hypercalls.txt => hypercalls.rst} | 129 ++++++++++-------- Documentation/virt/kvm/index.rst | 2 + 2 files changed, 75 insertions(+), 56 deletions(-) rename Documentation/virt/kvm/{hypercalls.txt => hypercalls.rst} (55%) diff --git a/Documentation/virt/kvm/hypercalls.txt b/Documentation/virt/kvm/hypercalls.rst similarity index 55% rename from Documentation/virt/kvm/hypercalls.txt rename to Documentation/virt/kvm/hypercalls.rst index 5f6d291bd004..dbaf207e560d 100644 --- a/Documentation/virt/kvm/hypercalls.txt +++ b/Documentation/virt/kvm/hypercalls.rst @@ -1,5 +1,9 @@ -Linux KVM Hypercall: +.. SPDX-License-Identifier: GPL-2.0 + =================== +Linux KVM Hypercall +=================== + X86: KVM Hypercalls have a three-byte sequence of either the vmcall or the vmmcall instruction. The hypervisor can replace it with instructions that are @@ -20,7 +24,7 @@ S390: For further information on the S390 diagnose call as supported by KVM, refer to Documentation/virt/kvm/s390-diag.txt. - PowerPC: +PowerPC: It uses R3-R10 and hypercall number in R11. R4-R11 are used as output registers. Return value is placed in R3. @@ -34,7 +38,8 @@ MIPS: the return value is placed in $2 (v0). KVM Hypercalls Documentation -=========================== +============================ + The template for each hypercall is: 1. Hypercall name. 2. Architecture(s) @@ -43,56 +48,64 @@ The template for each hypercall is: 1. KVM_HC_VAPIC_POLL_IRQ ------------------------ -Architecture: x86 -Status: active -Purpose: Trigger guest exit so that the host can check for pending -interrupts on reentry. + +:Architecture: x86 +:Status: active +:Purpose: Trigger guest exit so that the host can check for pending + interrupts on reentry. 2. KVM_HC_MMU_OP ------------------------- -Architecture: x86 -Status: deprecated. -Purpose: Support MMU operations such as writing to PTE, -flushing TLB, release PT. +---------------- + +:Architecture: x86 +:Status: deprecated. +:Purpose: Support MMU operations such as writing to PTE, + flushing TLB, release PT. 3. KVM_HC_FEATURES ------------------------- -Architecture: PPC -Status: active -Purpose: Expose hypercall availability to the guest. On x86 platforms, cpuid -used to enumerate which hypercalls are available. On PPC, either device tree -based lookup ( which is also what EPAPR dictates) OR KVM specific enumeration -mechanism (which is this hypercall) can be used. +------------------ + +:Architecture: PPC +:Status: active +:Purpose: Expose hypercall availability to the guest. On x86 platforms, cpuid + used to enumerate which hypercalls are available. On PPC, either + device tree based lookup ( which is also what EPAPR dictates) + OR KVM specific enumeration mechanism (which is this hypercall) + can be used. 4. KVM_HC_PPC_MAP_MAGIC_PAGE ------------------------- -Architecture: PPC -Status: active -Purpose: To enable communication between the hypervisor and guest there is a -shared page that contains parts of supervisor visible register state. -The guest can map this shared page to access its supervisor register through -memory using this hypercall. +---------------------------- + +:Architecture: PPC +:Status: active +:Purpose: To enable communication between the hypervisor and guest there is a + shared page that contains parts of supervisor visible register state. + The guest can map this shared page to access its supervisor register + through memory using this hypercall. 5. KVM_HC_KICK_CPU ------------------------- -Architecture: x86 -Status: active -Purpose: Hypercall used to wakeup a vcpu from HLT state -Usage example : A vcpu of a paravirtualized guest that is busywaiting in guest -kernel mode for an event to occur (ex: a spinlock to become available) can -execute HLT instruction once it has busy-waited for more than a threshold -time-interval. Execution of HLT instruction would cause the hypervisor to put -the vcpu to sleep until occurrence of an appropriate event. Another vcpu of the -same guest can wakeup the sleeping vcpu by issuing KVM_HC_KICK_CPU hypercall, -specifying APIC ID (a1) of the vcpu to be woken up. An additional argument (a0) -is used in the hypercall for future use. +------------------ + +:Architecture: x86 +:Status: active +:Purpose: Hypercall used to wakeup a vcpu from HLT state +:Usage example: + A vcpu of a paravirtualized guest that is busywaiting in guest + kernel mode for an event to occur (ex: a spinlock to become available) can + execute HLT instruction once it has busy-waited for more than a threshold + time-interval. Execution of HLT instruction would cause the hypervisor to put + the vcpu to sleep until occurrence of an appropriate event. Another vcpu of the + same guest can wakeup the sleeping vcpu by issuing KVM_HC_KICK_CPU hypercall, + specifying APIC ID (a1) of the vcpu to be woken up. An additional argument (a0) + is used in the hypercall for future use. 6. KVM_HC_CLOCK_PAIRING ------------------------- -Architecture: x86 -Status: active -Purpose: Hypercall used to synchronize host and guest clocks. +----------------------- +:Architecture: x86 +:Status: active +:Purpose: Hypercall used to synchronize host and guest clocks. + Usage: a0: guest physical address where host copies @@ -101,6 +114,8 @@ a0: guest physical address where host copies a1: clock_type, ATM only KVM_CLOCK_PAIRING_WALLCLOCK (0) is supported (corresponding to the host's CLOCK_REALTIME clock). + :: + struct kvm_clock_pairing { __s64 sec; __s64 nsec; @@ -123,15 +138,16 @@ Returns KVM_EOPNOTSUPP if the host does not use TSC clocksource, or if clock type is different than KVM_CLOCK_PAIRING_WALLCLOCK. 6. KVM_HC_SEND_IPI ------------------------- -Architecture: x86 -Status: active -Purpose: Send IPIs to multiple vCPUs. +------------------ -a0: lower part of the bitmap of destination APIC IDs -a1: higher part of the bitmap of destination APIC IDs -a2: the lowest APIC ID in bitmap -a3: APIC ICR +:Architecture: x86 +:Status: active +:Purpose: Send IPIs to multiple vCPUs. + +- a0: lower part of the bitmap of destination APIC IDs +- a1: higher part of the bitmap of destination APIC IDs +- a2: the lowest APIC ID in bitmap +- a3: APIC ICR The hypercall lets a guest send multicast IPIs, with at most 128 128 destinations per hypercall in 64-bit mode and 64 vCPUs per @@ -143,12 +159,13 @@ corresponds to the APIC ID a2+1, and so on. Returns the number of CPUs to which the IPIs were delivered successfully. 7. KVM_HC_SCHED_YIELD ------------------------- -Architecture: x86 -Status: active -Purpose: Hypercall used to yield if the IPI target vCPU is preempted +--------------------- + +:Architecture: x86 +:Status: active +:Purpose: Hypercall used to yield if the IPI target vCPU is preempted a0: destination APIC ID -Usage example: When sending a call-function IPI-many to vCPUs, yield if -any of the IPI target vCPUs was preempted. +:Usage example: When sending a call-function IPI-many to vCPUs, yield if + any of the IPI target vCPUs was preempted. diff --git a/Documentation/virt/kvm/index.rst b/Documentation/virt/kvm/index.rst index 6fe79185b9bc..ac83bc588f7e 100644 --- a/Documentation/virt/kvm/index.rst +++ b/Documentation/virt/kvm/index.rst @@ -11,8 +11,10 @@ KVM amd-memory-encryption cpuid halt-polling + hypercalls msr vcpu-requests arm/index + devices/index