From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 1/7] KVM: Add a route layer to convert MSI message to GSI Date: Thu, 08 Jan 2009 17:08:25 +0200 Message-ID: <496616E9.5040007@redhat.com> References: <1231411535-2461-1-git-send-email-sheng@linux.intel.com> <1231411535-2461-2-git-send-email-sheng@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm@vger.kernel.org To: Sheng Yang Return-path: Received: from mx2.redhat.com ([66.187.237.31]:54452 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753631AbZAHPIa (ORCPT ); Thu, 8 Jan 2009 10:08:30 -0500 In-Reply-To: <1231411535-2461-2-git-send-email-sheng@linux.intel.com> Sender: kvm-owner@vger.kernel.org List-ID: Sheng Yang wrote: > Avi's purpose, to use single kvm_set_irq() to deal with all interrupt, including > MSI. So here is it. > > struct gsi_route_entry is a mapping from a special gsi(with KVM_GSI_MSG_MASK) to > MSI/MSI-X message address/data. And the struct can also be extended for other > purpose. > > Now we support up to 256 gsi_route_entry mapping, and gsi is allocated by kernel and > provide two ioctls to userspace, which is more flexiable. > > @@ -553,4 +558,25 @@ struct kvm_assigned_irq { > #define KVM_DEV_IRQ_ASSIGN_MSI_ACTION KVM_DEV_IRQ_ASSIGN_ENABLE_MSI > #define KVM_DEV_IRQ_ASSIGN_ENABLE_MSI (1 << 0) > > +struct kvm_gsi_route_guest { > + __u32 entries_nr; > Need padding here otherwise offsetof(entries) will differ on 32-bit and 64-bit kernels. > + struct kvm_gsi_route_entry_guest *entries; > Like Marcelo says, zero sized array is better here. > +}; > + > +#define KVM_GSI_ROUTE_MSI (1 << 0) > This looks like a flag. Shouldn't it be a type? > +struct kvm_gsi_route_entry_guest { > what does _guest mean here? almost all kvm stuff is _guest related. > + __u32 gsi; > + __u32 type; > + __u32 flags; > + __u32 reserved; > + union { > + struct { > + __u32 addr_lo; > + __u32 addr_hi; > + __u32 data; > + } msi; > + __u32 padding[8]; > + }; > +}; > + > Since we replace the entire table every time, how do ioapic/pic gsis work? > > /* The guest did something we don't support. */ > @@ -336,6 +339,19 @@ void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq, > struct kvm_irq_mask_notifier *kimn); > void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask); > > +#define KVM_GSI_ROUTE_MASK 0x1000000ull > +struct kvm_gsi_route_entry { > + u32 gsi; > + u32 type; > + u32 flags; > + u32 reserved; > + union { > + struct msi_msg msi; > + u32 reserved[8]; > No need for reserved fields in kernel data. > + }; > + struct hlist_node link; > +}; > @@ -123,3 +123,73 @@ void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask) > kimn->func(kimn, mask); > } > > +int kvm_update_gsi_route(struct kvm *kvm, struct kvm_gsi_route_entry *entry) > +{ > + struct kvm_gsi_route_entry *found_entry, *new_entry; > + int r, gsi; > + > + mutex_lock(&kvm->lock); > + /* Find whether we need a update or a new entry */ > + found_entry = kvm_find_gsi_route_entry(kvm, entry->gsi); > + if (found_entry) > + *found_entry = *entry; > + else { > + gsi = find_first_zero_bit(kvm->gsi_route_bitmap, > + KVM_NR_GSI_ROUTE_ENTRIES); > + if (gsi >= KVM_NR_GSI_ROUTE_ENTRIES) { > + r = -ENOSPC; > + goto out; > + } > + new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); > + if (!new_entry) { > + r = -ENOMEM; > + goto out; > + } > + *new_entry = *entry; > + entry->gsi = gsi | KVM_GSI_ROUTE_MASK; > + __set_bit(gsi, kvm->gsi_route_bitmap); > + hlist_add_head(&new_entry->link, &kvm->gsi_route_list); > + } > + r = 0; > +out: > + mutex_unlock(&kvm->lock); > + return r; > +} > Why not throw everything and set the new table? I didn't see where you respond the new KVM_CAP. It looks like a good place to return the maximum size of the table. -- error compiling committee.c: too many arguments to function