Re: [PATCH kvmtool 15/21] vfio: Refactor ioport trap handler
From: Andre Przywara <andre.przywara@arm.com>
Date: 2021-02-18 15:55:12
Also in:
kvmarm, linux-arm-kernel
On Tue, 16 Feb 2021 14:47:31 +0000 Alexandru Elisei [off-list ref] wrote:
Hi Andre, Looks good, one nitpick below. On 12/10/20 2:29 PM, Andre Przywara wrote:quoted
With the planned retirement of the special ioport emulation code, we need to provide an emulation function compatible with the MMIO prototype. Adjust the I/O port trap handler to use that new function, and provide shims to implement the old ioport interface, for now. Signed-off-by: Andre Przywara <andre.przywara@arm.com> --- vfio/core.c | 51 ++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 36 insertions(+), 15 deletions(-)diff --git a/vfio/core.c b/vfio/core.c index 0b45e78b..f55f1f87 100644 --- a/vfio/core.c +++ b/vfio/core.c@@ -81,15 +81,12 @@ out_free_buf: return ret; } -static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu, - u16 port, void *data, int len) +static bool _vfio_ioport_in(struct vfio_region *region, u32 offset, + void *data, int len) { - u32 val; - ssize_t nr; - struct vfio_region *region = ioport->priv; struct vfio_device *vdev = region->vdev; - - u32 offset = port - region->port_base; + ssize_t nr; + u32 val; if (!(region->info.flags & VFIO_REGION_INFO_FLAG_READ)) return false;@@ -97,7 +94,7 @@ static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu, nr = pread(vdev->fd, &val, len, region->info.offset + offset); if (nr != len) { vfio_dev_err(vdev, "could not read %d bytes from I/O port 0x%x\n", - len, port); + len, offset);To keep things functionally identical, shouldn't that be offset + region->port_base? I think it's easier to identify the device when we have the PCI ioport address.
Yeah, true. Although I think "vfio_dev_err(vdev, ..." already indicates the device at fault, but indeed the actual ioport address is more canonical to use. Thanks, Andre
Thanks, Alexquoted
return false; }@@ -118,15 +115,13 @@ static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu, return true; } -static bool vfio_ioport_out(struct ioport *ioport, struct kvm_cpu *vcpu, - u16 port, void *data, int len) +static bool _vfio_ioport_out(struct vfio_region *region, u32 offset, + void *data, int len) { - u32 val; - ssize_t nr; - struct vfio_region *region = ioport->priv; struct vfio_device *vdev = region->vdev; + ssize_t nr; + u32 val; - u32 offset = port - region->port_base; if (!(region->info.flags & VFIO_REGION_INFO_FLAG_WRITE)) return false;@@ -148,11 +143,37 @@ static bool vfio_ioport_out(struct ioport *ioport, struct kvm_cpu *vcpu, nr = pwrite(vdev->fd, &val, len, region->info.offset + offset); if (nr != len) vfio_dev_err(vdev, "could not write %d bytes to I/O port 0x%x", - len, port); + len, offset); return nr == len; } +static void vfio_ioport_mmio(struct kvm_cpu *vcpu, u64 addr, u8 *data, u32 len, + u8 is_write, void *ptr) +{ + struct vfio_region *region = ptr; + u32 offset = addr - region->port_base; + + if (is_write) + _vfio_ioport_out(region, offset, data, len); + else + _vfio_ioport_in(region, offset, data, len); +} + +static bool vfio_ioport_out(struct ioport *ioport, struct kvm_cpu *vcpu, + u16 port, void *data, int len) +{ + vfio_ioport_mmio(vcpu, port, data, len, true, ioport->priv); + return true; +} + +static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu, + u16 port, void *data, int len) +{ + vfio_ioport_mmio(vcpu, port, data, len, false, ioport->priv); + return true; +} + static struct ioport_operations vfio_ioport_ops = { .io_in = vfio_ioport_in, .io_out = vfio_ioport_out,