From: "Michael S. Tsirkin" <mst@redhat.com>
To: Sheng Yang <sheng@linux.intel.com>
Cc: Avi Kivity <avi@redhat.com>,
Marcelo Tosatti <mtosatti@redhat.com>,
Alex Williamson <alex.williamson@redhat.com>,
kvm@vger.kernel.org
Subject: Re: [PATCH 2/4] KVM: Add kvm_io_ext_data to IO handler
Date: Fri, 25 Feb 2011 10:12:30 +0200 [thread overview]
Message-ID: <20110225081230.GA17290@redhat.com> (raw)
In-Reply-To: <201102251123.30662.sheng@linux.intel.com>
On Fri, Feb 25, 2011 at 11:23:30AM +0800, Sheng Yang wrote:
> On Thursday 24 February 2011 18:22:19 Michael S. Tsirkin wrote:
> > On Thu, Feb 24, 2011 at 05:51:03PM +0800, Sheng Yang wrote:
> > > Add a new parameter to IO writing handler, so that we can transfer
> > > information from IO handler to caller.
> > >
> > > Signed-off-by: Sheng Yang <sheng@linux.intel.com>
> > > ---
> > >
> > > arch/x86/kvm/i8254.c | 6 ++++--
> > > arch/x86/kvm/i8259.c | 3 ++-
> > > arch/x86/kvm/lapic.c | 3 ++-
> > > arch/x86/kvm/x86.c | 13 ++++++++-----
> > > include/linux/kvm_host.h | 12 ++++++++++--
> > > virt/kvm/coalesced_mmio.c | 3 ++-
> > > virt/kvm/eventfd.c | 2 +-
> > > virt/kvm/ioapic.c | 2 +-
> > > virt/kvm/iodev.h | 6 ++++--
> > > virt/kvm/kvm_main.c | 4 ++--
> > > 10 files changed, 36 insertions(+), 18 deletions(-)
> > >
> > > diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
> > > index efad723..bd8f0c5 100644
> > > --- a/arch/x86/kvm/i8254.c
> > > +++ b/arch/x86/kvm/i8254.c
> > > @@ -439,7 +439,8 @@ static inline int pit_in_range(gpa_t addr)
> > >
> > > }
> > >
> > > static int pit_ioport_write(struct kvm_io_device *this,
> > >
> > > - gpa_t addr, int len, const void *data)
> > > + gpa_t addr, int len, const void *data,
> > > + struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct kvm_pit *pit = dev_to_pit(this);
> > > struct kvm_kpit_state *pit_state = &pit->pit_state;
> > >
> > > @@ -585,7 +586,8 @@ static int pit_ioport_read(struct kvm_io_device
> > > *this,
> > >
> > > }
> > >
> > > static int speaker_ioport_write(struct kvm_io_device *this,
> > >
> > > - gpa_t addr, int len, const void *data)
> > > + gpa_t addr, int len, const void *data,
> > > + struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct kvm_pit *pit = speaker_to_pit(this);
> > > struct kvm_kpit_state *pit_state = &pit->pit_state;
> > >
> > > diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
> > > index 3cece05..96b1070 100644
> > > --- a/arch/x86/kvm/i8259.c
> > > +++ b/arch/x86/kvm/i8259.c
> > > @@ -480,7 +480,8 @@ static inline struct kvm_pic *to_pic(struct
> > > kvm_io_device *dev)
> > >
> > > }
> > >
> > > static int picdev_write(struct kvm_io_device *this,
> > >
> > > - gpa_t addr, int len, const void *val)
> > > + gpa_t addr, int len, const void *val,
> > > + struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct kvm_pic *s = to_pic(this);
> > > unsigned char data = *(unsigned char *)val;
> > >
> > > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> > > index 93cf9d0..f413e9c 100644
> > > --- a/arch/x86/kvm/lapic.c
> > > +++ b/arch/x86/kvm/lapic.c
> > > @@ -836,7 +836,8 @@ static int apic_reg_write(struct kvm_lapic *apic, u32
> > > reg, u32 val)
> > >
> > > }
> > >
> > > static int apic_mmio_write(struct kvm_io_device *this,
> > >
> > > - gpa_t address, int len, const void *data)
> > > + gpa_t address, int len, const void *data,
> > > + struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct kvm_lapic *apic = to_lapic(this);
> > > unsigned int offset = address - apic->base_address;
> > >
> > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > > index fa708c9..21b84e2 100644
> > > --- a/arch/x86/kvm/x86.c
> > > +++ b/arch/x86/kvm/x86.c
> > > @@ -3571,13 +3571,14 @@ static void kvm_init_msr_list(void)
> > >
> > > }
> > >
> > > static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len,
> > >
> > > - const void *v)
> > > + const void *v, struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > if (vcpu->arch.apic &&
> > >
> > > - !kvm_iodevice_write(&vcpu->arch.apic->dev, addr, len, v))
> > > + !kvm_iodevice_write(&vcpu->arch.apic->dev, addr, len, v, ext_data))
> > >
> > > return 0;
> > >
> > > - return kvm_io_bus_write(vcpu->kvm, KVM_MMIO_BUS, addr, len, v);
> > > + return kvm_io_bus_write(vcpu->kvm, KVM_MMIO_BUS,
> > > + addr, len, v, ext_data);
> > >
> > > }
> > >
> > > static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len,
> > > void *v)
> > >
> > > @@ -3807,6 +3808,7 @@ static int emulator_write_emulated_onepage(unsigned
> > > long addr,
> > >
> > > struct kvm_vcpu *vcpu)
> > >
> > > {
> > >
> > > gpa_t gpa;
> > >
> > > + struct kvm_io_ext_data ext_data;
> > >
> > > gpa = kvm_mmu_gva_to_gpa_write(vcpu, addr, exception);
> > >
> > > @@ -3825,7 +3827,7 @@ mmio:
> > > /*
> > >
> > > * Is this MMIO handled locally?
> > > */
> > >
> > > - if (!vcpu_mmio_write(vcpu, gpa, bytes, val))
> > > + if (!vcpu_mmio_write(vcpu, gpa, bytes, val, &ext_data))
> > >
> > > return X86EMUL_CONTINUE;
> > >
> > > vcpu->mmio_needed = 1;
> > >
> > > @@ -3940,6 +3942,7 @@ static int kernel_pio(struct kvm_vcpu *vcpu, void
> > > *pd)
> > >
> > > {
> > >
> > > /* TODO: String I/O for in kernel device */
> > > int r;
> > >
> > > + struct kvm_io_ext_data ext_data;
> > >
> > > if (vcpu->arch.pio.in)
> > >
> > > r = kvm_io_bus_read(vcpu->kvm, KVM_PIO_BUS, vcpu->arch.pio.port,
> > >
> > > @@ -3947,7 +3950,7 @@ static int kernel_pio(struct kvm_vcpu *vcpu, void
> > > *pd)
> > >
> > > else
> > >
> > > r = kvm_io_bus_write(vcpu->kvm, KVM_PIO_BUS,
> > >
> > > vcpu->arch.pio.port, vcpu->arch.pio.size,
> > >
> > > - pd);
> > > + pd, &ext_data);
> > >
> > > return r;
> > >
> > > }
> > >
> > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> > > index 7d313e0..6bb211d 100644
> > > --- a/include/linux/kvm_host.h
> > > +++ b/include/linux/kvm_host.h
> > > @@ -68,8 +68,15 @@ enum kvm_bus {
> > >
> > > KVM_NR_BUSES
> > >
> > > };
> > >
> > > +struct kvm_io_ext_data {
> > > + int type;
> >
> > What values does this get? Please add documentation in comments.
>
> See the next patch.
> >
> > > + union {
> > > + char padding[256];
> > > + };
> >
> > So the structure size is 260 bytes?
> > What's the point of the padding?
>
> Reserved spaces. Also used in the next patch.
I was unable to find anything related to padding in the next patch.
This is an internal API, isn't it? So why reserve space? Further,
256 bytes is quite a lot to reserve. Also,
making the total size a power of 2 would seem to make more sense if we
do need to reserve any space.
> --
> regards
> Yang, Sheng
>
> >
> > > +};
> > > +
> > >
> > > int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
> > >
> > > - int len, const void *val);
> > > + int len, const void *val, struct kvm_io_ext_data *data);
> > >
> > > int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
> > > int len,
> > >
> > > void *val);
> > >
> > > int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
> > >
> > > @@ -113,7 +120,8 @@ struct kvm_io_device_ops {
> > >
> > > int (*write)(struct kvm_io_device *this,
> > >
> > > gpa_t addr,
> > > int len,
> > >
> > > - const void *val);
> > > + const void *val,
> > > + struct kvm_io_ext_data *data);
> > >
> > > void (*destructor)(struct kvm_io_device *this);
> > >
> > > };
> > >
> > > diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
> > > index fc84875..37b254c 100644
> > > --- a/virt/kvm/coalesced_mmio.c
> > > +++ b/virt/kvm/coalesced_mmio.c
> > > @@ -59,7 +59,8 @@ static int coalesced_mmio_in_range(struct
> > > kvm_coalesced_mmio_dev *dev,
> > >
> > > }
> > >
> > > static int coalesced_mmio_write(struct kvm_io_device *this,
> > >
> > > - gpa_t addr, int len, const void *val)
> > > + gpa_t addr, int len, const void *val,
> > > + struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
> > > struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;
> > >
> > > diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
> > > index 2ca4535..8edd757 100644
> > > --- a/virt/kvm/eventfd.c
> > > +++ b/virt/kvm/eventfd.c
> > > @@ -483,7 +483,7 @@ ioeventfd_in_range(struct _ioeventfd *p, gpa_t addr,
> > > int len, const void *val)
> > >
> > > /* MMIO/PIO writes trigger an event if the addr/val match */
> > > static int
> > > ioeventfd_write(struct kvm_io_device *this, gpa_t addr, int len,
> > >
> > > - const void *val)
> > > + const void *val, struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct _ioeventfd *p = to_ioeventfd(this);
> > >
> > > diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
> > > index 0b9df83..6a027ef 100644
> > > --- a/virt/kvm/ioapic.c
> > > +++ b/virt/kvm/ioapic.c
> > > @@ -321,7 +321,7 @@ static int ioapic_mmio_read(struct kvm_io_device
> > > *this, gpa_t addr, int len,
> > >
> > > }
> > >
> > > static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int
> > > len,
> > >
> > > - const void *val)
> > > + const void *val, struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > struct kvm_ioapic *ioapic = to_ioapic(this);
> > > u32 data;
> > >
> > > diff --git a/virt/kvm/iodev.h b/virt/kvm/iodev.h
> > > index d1f5651..340ab79 100644
> > > --- a/virt/kvm/iodev.h
> > > +++ b/virt/kvm/iodev.h
> > > @@ -33,9 +33,11 @@ static inline int kvm_iodevice_read(struct
> > > kvm_io_device *dev,
> > >
> > > }
> > >
> > > static inline int kvm_iodevice_write(struct kvm_io_device *dev,
> > >
> > > - gpa_t addr, int l, const void *v)
> > > + gpa_t addr, int l, const void *v,
> > > + struct kvm_io_ext_data *data)
> > >
> > > {
> > >
> > > - return dev->ops->write ? dev->ops->write(dev, addr, l, v) :
> > > -EOPNOTSUPP; + return dev->ops->write ?
> > > + dev->ops->write(dev, addr, l, v, data) : -EOPNOTSUPP;
> > >
> > > }
> > >
> > > static inline void kvm_iodevice_destructor(struct kvm_io_device *dev)
> > >
> > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> > > index b1b6cbb..a61f90e 100644
> > > --- a/virt/kvm/kvm_main.c
> > > +++ b/virt/kvm/kvm_main.c
> > > @@ -2221,14 +2221,14 @@ static void kvm_io_bus_destroy(struct kvm_io_bus
> > > *bus)
> > >
> > > /* kvm_io_bus_write - called under kvm->slots_lock */
> > > int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
> > >
> > > - int len, const void *val)
> > > + int len, const void *val, struct kvm_io_ext_data *ext_data)
> > >
> > > {
> > >
> > > int i;
> > > struct kvm_io_bus *bus;
> > >
> > > bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
> > > for (i = 0; i < bus->dev_count; i++)
> > >
> > > - if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
> > > + if (!kvm_iodevice_write(bus->devs[i], addr, len, val, ext_data))
> > >
> > > return 0;
> > >
> > > return -EOPNOTSUPP;
> > >
> > > }
next prev parent reply other threads:[~2011-02-25 8:12 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-24 9:51 [PATCH 0/4 v10] MSI-X MMIO support for KVM Sheng Yang
2011-02-24 9:51 ` [PATCH 1/4] KVM: Move struct kvm_io_device to kvm_host.h Sheng Yang
2011-02-24 9:51 ` [PATCH 2/4] KVM: Add kvm_io_ext_data to IO handler Sheng Yang
2011-02-24 10:22 ` Michael S. Tsirkin
2011-02-25 3:23 ` Sheng Yang
2011-02-25 8:12 ` Michael S. Tsirkin [this message]
2011-02-28 5:13 ` Sheng Yang
2011-02-24 9:51 ` [PATCH 3/4] KVM: Emulate MSI-X table in kernel Sheng Yang
2011-02-24 10:45 ` Michael S. Tsirkin
2011-02-25 6:28 ` Sheng Yang
2011-02-25 8:29 ` Michael S. Tsirkin
2011-02-28 5:18 ` Sheng Yang
2011-03-01 20:18 ` Marcelo Tosatti
2011-03-01 20:59 ` Michael S. Tsirkin
2011-03-02 1:23 ` Sheng Yang
2011-02-25 6:50 ` Sheng Yang
2011-02-25 6:50 ` [PATCH 3/4 v10 UPDATED] " Sheng Yang
2011-02-24 9:51 ` [PATCH 4/4] KVM: Add documents for MSI-X MMIO API Sheng Yang
-- strict thread matches above, loose matches on Subject: below --
2011-03-02 7:26 [PATCH 0/4 v12] MSI-X MMIO support for KVM Sheng Yang
2011-03-02 7:26 ` [PATCH 2/4] KVM: Add kvm_io_ext_data to IO handler Sheng Yang
2011-02-28 7:20 [PATCH 0/4 v11] MSI-X MMIO support for KVM Sheng Yang
2011-02-28 7:20 ` [PATCH 2/4] KVM: Add kvm_io_ext_data to IO handler Sheng Yang
2011-02-18 8:53 [PATCH 0/4 v9] MSI-X MMIO support for KVM Sheng Yang
2011-02-18 8:53 ` [PATCH 2/4] KVM: Add kvm_io_ext_data to IO handler Sheng Yang
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