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(). Tested-by: Nicolin Chen <[email protected]> Signed-off-by: Shameer Kolothum <[email protected]> --- hw/arm/smmuv3-accel.c | 62 +++++++++++++++++++++++++++++++++++++++++++ hw/arm/smmuv3-accel.h | 2 ++ 2 files changed, 64 insertions(+) diff --git a/hw/arm/smmuv3-accel.c b/hw/arm/smmuv3-accel.c index 2ca0d1deac..beffb8aa94 100644 --- a/hw/arm/smmuv3-accel.c +++ b/hw/arm/smmuv3-accel.c @@ -390,6 +390,48 @@ 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; + SMMUv3AccelState *accel = s->s_accel; + struct { + struct iommufd_vevent_header hdr; + struct iommu_vevent_arm_smmuv3 vevent; + } buf; + uint32_t last_seq = accel->last_event_seq; + ssize_t bytes; + + bytes = read(accel->veventq->veventq_fd, &buf, sizeof(buf)); + if (bytes <= 0) { + if (errno == EAGAIN || errno == EINTR) { + return; + } + error_report_once("vEVENTQ: read failed (%m)"); + return; + } + + if (bytes == sizeof(buf.hdr) && + (buf.hdr.flags & IOMMU_VEVENTQ_FLAG_LOST_EVENTS)) { + error_report_once("vEVENTQ has lost events"); + accel->event_start = false; + return; + } + if (bytes < sizeof(buf)) { + error_report_once("vEVENTQ: incomplete read (%zd/%zd bytes)", + bytes, sizeof(buf)); + return; + } + + /* Check sequence in hdr for lost events if any */ + if (accel->event_start && (buf.hdr.sequence - last_seq != 1)) { + error_report_once("vEVENTQ: detected lost %u event(s)", + buf.hdr.sequence - last_seq - 1); + } + accel->last_event_seq = buf.hdr.sequence; + accel->event_start = true; + smmuv3_propagate_event(s, (Evt *)&buf.vevent); +} + static void smmuv3_accel_free_veventq(SMMUv3AccelState *accel) { IOMMUFDVeventq *veventq = accel->veventq; @@ -397,6 +439,7 @@ 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 +467,7 @@ bool smmuv3_accel_alloc_veventq(SMMUv3State *s, Error **errp) IOMMUFDVeventq *veventq; uint32_t veventq_id; uint32_t veventq_fd; + int flags; if (!accel->viommu) { return true; @@ -445,12 +489,30 @@ bool smmuv3_accel_alloc_veventq(SMMUv3State *s, Error **errp) return false; } + flags = fcntl(veventq_fd, F_GETFL); + if (flags < 0) { + error_setg(errp, "Failed to get flags for vEVENTQ fd"); + goto free_veventq; + } + if (fcntl(veventq_fd, F_SETFL, O_NONBLOCK | flags) < 0) { + error_setg(errp, "Failed to set O_NONBLOCK on vEVENTQ fd"); + goto free_veventq; + } + veventq = g_new(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 diff --git a/hw/arm/smmuv3-accel.h b/hw/arm/smmuv3-accel.h index dba6c71de5..c9c10e55c3 100644 --- a/hw/arm/smmuv3-accel.h +++ b/hw/arm/smmuv3-accel.h @@ -23,6 +23,8 @@ typedef struct SMMUv3AccelState { IOMMUFDViommu *viommu; IOMMUFDVeventq *veventq; + uint32_t last_event_seq; + bool event_start; uint32_t bypass_hwpt_id; uint32_t abort_hwpt_id; QLIST_HEAD(, SMMUv3AccelDevice) device_list; -- 2.43.0
