Install an event handler on the vEVENTQ fd to read and propagate host generated vIOMMU events to the guest.
The handler runs in QEMU's main loop, using a non-blocking fd registered via qemu_set_fd_handler(). Reviewed-by: Eric Auger <[email protected]> Reviewed-by: Nicolin Chen <[email protected]> Tested-by: Nicolin Chen <[email protected]> Signed-off-by: Shameer Kolothum <[email protected]> --- hw/arm/smmuv3-accel.c | 64 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c index f703ea1aac..17306cd04b 100644 --- a/hw/arm/smmuv3-accel.c +++ b/hw/arm/smmuv3-accel.c @@ -390,6 +390,50 @@ bool smmuv3_accel_issue_inv_cmd(SMMUv3State *bs, void *cmd, SMMUDevice *sdev, sizeof(Cmd), &entry_num, cmd, errp); } +static void smmuv3_accel_event_read(void *opaque) +{ + SMMUv3State *s = opaque; + IOMMUFDVeventq *veventq = s->s_accel->veventq; + struct { + struct iommufd_vevent_header hdr; + struct iommu_vevent_arm_smmuv3 vevent; + } buf; + enum iommu_veventq_type type = IOMMU_VEVENTQ_TYPE_ARM_SMMUV3; + uint32_t id = veventq->veventq_id; + uint32_t last_seq = veventq->last_event_seq; + ssize_t bytes; + + bytes = read(veventq->veventq_fd, &buf, sizeof(buf)); + if (bytes <= 0) { + if (errno == EAGAIN || errno == EINTR) { + return; + } + error_report_once("vEVENTQ(type %u id %u): read failed (%m)", type, id); + return; + } + + if (bytes == sizeof(buf.hdr) && + (buf.hdr.flags & IOMMU_VEVENTQ_FLAG_LOST_EVENTS)) { + error_report_once("vEVENTQ(type %u id %u): overflowed", type, id); + veventq->event_start = false; + return; + } + if (bytes < sizeof(buf)) { + error_report_once("vEVENTQ(type %u id %u): short read(%zd/%zd bytes)", + type, id, bytes, sizeof(buf)); + return; + } + + /* Check sequence in hdr for lost events if any */ + if (veventq->event_start && (buf.hdr.sequence - last_seq != 1)) { + error_report_once("vEVENTQ(type %u id %u): lost %u event(s)", + type, id, buf.hdr.sequence - last_seq - 1); + } + veventq->last_event_seq = buf.hdr.sequence; + veventq->event_start = true; + smmuv3_propagate_event(s, (Evt *)&buf.vevent); +} + static void smmuv3_accel_free_veventq(SMMUv3AccelState *accel) { IOMMUFDVeventq *veventq = accel->veventq; @@ -397,6 +441,7 @@ static void smmuv3_accel_free_veventq(SMMUv3AccelState *accel) if (!veventq) { return; } + qemu_set_fd_handler(veventq->veventq_fd, NULL, NULL, NULL); close(veventq->veventq_fd); iommufd_backend_free_id(accel->viommu->iommufd, veventq->veventq_id); g_free(veventq); @@ -424,6 +469,7 @@ bool smmuv3_accel_alloc_veventq(SMMUv3State *s, Error **errp) IOMMUFDVeventq *veventq; uint32_t veventq_id; uint32_t veventq_fd; + int flags; if (!accel || !accel->viommu) { return true; @@ -445,12 +491,30 @@ bool smmuv3_accel_alloc_veventq(SMMUv3State *s, Error **errp) return false; } + flags = fcntl(veventq_fd, F_GETFL); + if (flags < 0) { + error_setg_errno(errp, errno, "Failed to get flags for vEVENTQ fd"); + goto free_veventq; + } + if (fcntl(veventq_fd, F_SETFL, flags | O_NONBLOCK) < 0) { + error_setg_errno(errp, errno, "Failed to set O_NONBLOCK on vEVENTQ fd"); + goto free_veventq; + } + veventq = g_new0(IOMMUFDVeventq, 1); veventq->veventq_id = veventq_id; veventq->veventq_fd = veventq_fd; veventq->viommu = accel->viommu; accel->veventq = veventq; + + /* Set up event handler for veventq fd */ + qemu_set_fd_handler(veventq_fd, smmuv3_accel_event_read, NULL, s); return true; + +free_veventq: + close(veventq_fd); + iommufd_backend_free_id(accel->viommu->iommufd, veventq_id); + return false; } static bool -- 2.43.0
