From c42767f2bbd18d4ec895395c01c64bbec16b5b84 Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Thu, 11 Dec 2014 14:25:12 +0100 Subject: s390x/virtio-ccw: add virtio set-revision call Handle the virtio-ccw revision according to what the guest sets. When revision 1 is selected, we have a virtio-1 standard device with byteswapping for the virtio rings. When a channel gets disabled, we have to revert to the legacy behavior in case the next user of the device does not negotiate the revision 1 anymore (e.g. the boot firmware uses revision 1, but the operating system only uses the legacy mode). Note that revisions > 0 are still disabled. [CH: assure memory accesses are always BE] Signed-off-by: Thomas Huth Signed-off-by: Cornelia Huck Acked-by: Michael S. Tsirkin --- hw/s390x/virtio-ccw.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 76 insertions(+), 2 deletions(-) (limited to 'hw/s390x/virtio-ccw.c') diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c index 2c817719d6..0b3a0e7657 100644 --- a/hw/s390x/virtio-ccw.c +++ b/hw/s390x/virtio-ccw.c @@ -21,6 +21,7 @@ #include "hw/sysbus.h" #include "qemu/bitops.h" #include "qemu/error-report.h" +#include "hw/virtio/virtio-access.h" #include "hw/virtio/virtio-bus.h" #include "hw/s390x/adapter.h" #include "hw/s390x/s390_flic.h" @@ -261,6 +262,12 @@ typedef struct VirtioThinintInfo { uint8_t isc; } QEMU_PACKED VirtioThinintInfo; +typedef struct VirtioRevInfo { + uint16_t revision; + uint16_t length; + uint8_t data[0]; +} QEMU_PACKED VirtioRevInfo; + /* Specify where the virtqueues for the subchannel are in guest memory. */ static int virtio_ccw_set_vqs(SubchDev *sch, uint64_t addr, uint32_t align, uint16_t index, uint16_t num) @@ -319,6 +326,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) { int ret; VqInfoBlock info; + VirtioRevInfo revinfo; uint8_t status; VirtioFeatDesc features; void *config; @@ -401,7 +409,16 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) MEMTXATTRS_UNSPECIFIED, NULL); if (features.index == 0) { - features.features = vdev->host_features; + features.features = (uint32_t)vdev->host_features; + } else if (features.index == 1) { + features.features = (uint32_t)(vdev->host_features >> 32); + /* + * Don't offer version 1 to the guest if it did not + * negotiate at least revision 1. + */ + if (dev->revision <= 0) { + features.features &= ~(1 << (VIRTIO_F_VERSION_1 - 32)); + } } else { /* Return zeroes if the guest supports more feature bits. */ features.features = 0; @@ -437,7 +454,20 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) MEMTXATTRS_UNSPECIFIED, NULL); if (features.index == 0) { - virtio_set_features(vdev, features.features); + virtio_set_features(vdev, + (vdev->guest_features & 0xffffffff00000000ULL) | + features.features); + } else if (features.index == 1) { + /* + * The guest should not set version 1 if it didn't + * negotiate a revision >= 1. + */ + if (dev->revision <= 0) { + features.features &= ~(1 << (VIRTIO_F_VERSION_1 - 32)); + } + virtio_set_features(vdev, + (vdev->guest_features & 0x00000000ffffffffULL) | + ((uint64_t)features.features << 32)); } else { /* * If the guest supports more feature bits, assert that it @@ -658,6 +688,40 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) } } break; + case CCW_CMD_SET_VIRTIO_REV: + len = sizeof(revinfo); + if (ccw.count < len) { + ret = -EINVAL; + break; + } + if (!ccw.cda) { + ret = -EFAULT; + break; + } + revinfo.revision = + address_space_lduw_be(&address_space_memory, ccw.cda, + MEMTXATTRS_UNSPECIFIED, NULL); + revinfo.length = + address_space_lduw_be(&address_space_memory, + ccw.cda + sizeof(revinfo.revision), + MEMTXATTRS_UNSPECIFIED, NULL); + if (ccw.count < len + revinfo.length || + (check_len && ccw.count > len + revinfo.length)) { + ret = -EINVAL; + break; + } + /* + * Once we start to support revisions with additional data, we'll + * need to fetch it here. Nothing to do for now, though. + */ + if (dev->revision >= 0 || + revinfo.revision > virtio_ccw_rev_max(vdev)) { + ret = -ENOSYS; + break; + } + ret = 0; + dev->revision = revinfo.revision; + break; default: ret = -ENOSYS; break; @@ -665,6 +729,13 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) return ret; } +static void virtio_sch_disable_cb(SubchDev *sch) +{ + VirtioCcwDevice *dev = sch->driver_data; + + dev->revision = -1; +} + static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp) { unsigned int cssid = 0; @@ -784,12 +855,15 @@ static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp) css_sch_build_virtual_schib(sch, 0, VIRTIO_CCW_CHPID_TYPE); sch->ccw_cb = virtio_ccw_cb; + sch->disable_cb = virtio_sch_disable_cb; /* Build senseid data. */ memset(&sch->id, 0, sizeof(SenseId)); sch->id.reserved = 0xff; sch->id.cu_type = VIRTIO_CCW_CU_TYPE; + dev->revision = -1; + if (k->realize) { k->realize(dev, &err); } -- cgit v1.2.3