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envelope-from=jrossi@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 5/6/26 2:20 PM, Zhuoying Cai wrote: > On 5/4/26 6:16 PM, jrossi@linux.ibm.com wrote: >> From: Jared Rossi >> >> The initial support for virtio-blk-pci IPL devices used a single virt-queue, but >> other device types require multiple queues, and for PCI device types this also >> requires a per-queue notification offset. >> >> Add a PCI notify field to the VRing struct so that each queue has a unique >> notify offset. Also re-select the target queue before writing buffers to >> ensure the proper queue is active. >> >> Signed-off-by: Jared Rossi >> --- >> pc-bios/s390-ccw/virtio-pci.c | 36 ++++++++++++++++++++++------------- >> pc-bios/s390-ccw/virtio-pci.h | 3 ++- >> pc-bios/s390-ccw/virtio.c | 4 +++- >> pc-bios/s390-ccw/virtio.h | 1 + >> 4 files changed, 29 insertions(+), 15 deletions(-) >> >> diff --git a/pc-bios/s390-ccw/virtio-pci.c b/pc-bios/s390-ccw/virtio-pci.c >> index 53bdb52e76..736869f4f5 100644 >> --- a/pc-bios/s390-ccw/virtio-pci.c >> +++ b/pc-bios/s390-ccw/virtio-pci.c >> @@ -74,10 +74,10 @@ int virtio_pci_reset(VDev *vdev) >> return 0; >> } >> >> -long virtio_pci_notify(int vq_id) >> +long virtio_pci_notify(VRing *vr) >> { >> - uint32_t offset = n_cap.off + notify_mult * q_notify_offset; >> - return vpci_bswap16_write(offset, n_cap.bar, (uint16_t) vq_id); >> + uint32_t offset = n_cap.off + notify_mult * vr->pci_notify; >> + return vpci_bswap16_write(offset, n_cap.bar, (uint16_t) vr->id); >> } >> >> /* >> @@ -166,7 +166,7 @@ int vpci_read_flex(uint64_t offset, uint8_t pcias, void *buf, int len) >> return 0; >> } >> >> -static int vpci_set_selected_vq(uint16_t queue_num) >> +int vpci_set_selected_vq(uint16_t queue_num) >> { >> return vpci_bswap16_write(c_cap.off + VPCI_C_OFFSET_Q_SELECT, c_cap.bar, queue_num); >> } >> @@ -332,7 +332,6 @@ int virtio_pci_setup(VDev *vdev) >> VRing *vr; >> int rc; >> uint8_t status; >> - uint16_t vq_size; >> int i = 0; >> >> vdev->guessed_disk_nature = VIRTIO_GDN_NONE; >> @@ -380,28 +379,39 @@ int virtio_pci_setup(VDev *vdev) >> return -EIO; >> } >> >> - if (vpci_read_bswap16(VPCI_C_OFFSET_Q_SIZE, c_cap.bar, &vq_size)) { >> - puts("Failed to read virt-queue configuration"); >> - return -EIO; >> - } >> - >> /* Configure virt-queues for pci */ >> for (i = 0; i < vdev->nr_vqs; i++) { >> + uint16_t vq_size; >> + uint16_t vq_notify; >> VqInfo info = { >> .queue = (unsigned long long) virtio_get_ring_area(i), >> .align = KVM_S390_VIRTIO_RING_ALIGN, >> .index = i, >> - .num = vq_size, >> + .num = 0, >> }; >> >> vr = &vdev->vrings[i]; >> - vring_init(vr, &info); >> >> - if (vpci_set_selected_vq(vr->id)) { >> + if (vpci_set_selected_vq(i)) { >> puts("Failed to set selected virt-queue"); >> return -EIO; >> } >> >> + if (vpci_read_bswap16(VPCI_C_OFFSET_Q_SIZE, c_cap.bar, &vq_size)) { > Small nit: c_cap.off + VPCI_C_OFFSET_Q_SIZE Ah, this is actually not just a small nit!  Although the common capabilities offset is 0 in the current QEMU implementation there is nothing preventing it from being a different offset in the future.  So it must be included, otherwise a non-zero value would break it.  Good catch. > >> + puts("Failed to read virt-queue configuration"); >> + return -EIO; >> + } >> + >> + info.num = vq_size; >> + >> + if (vpci_read_bswap16(c_cap.off + VPCI_C_OFFSET_Q_NOFF, c_cap.bar, &vq_notify)) { >> + puts("Failed to read virt-queue configuration"); >> + return -EIO; >> + } > Since the notification offset is now read per queue, should we remove > the same read in virtio_pci_read_pci_cap_config() as well as the global > q_notify_offset variable? > > if (rc || vpci_read_bswap16(c_cap.off + VPCI_C_OFFSET_Q_NOFF, c_cap.bar, > &q_notify_offset)) Yes, that should be removed.  I will take care of it for V2. Thanks. > >> + >> + vr->pci_notify = vq_notify; >> + vring_init(vr, &info); >> + >> rc = set_pci_vq_addr(VPCI_C_OFFSET_Q_DESCLO, vr->desc); >> rc |= set_pci_vq_addr(VPCI_C_OFFSET_Q_AVAILLO, vr->avail); >> rc |= set_pci_vq_addr(VPCI_C_OFFSET_Q_USEDLO, vr->used); >> diff --git a/pc-bios/s390-ccw/virtio-pci.h b/pc-bios/s390-ccw/virtio-pci.h >> index 90d07cb9a7..993fc285ac 100644 >> --- a/pc-bios/s390-ccw/virtio-pci.h >> +++ b/pc-bios/s390-ccw/virtio-pci.h >> @@ -62,9 +62,10 @@ struct VirtioPciCap { >> }; >> typedef struct VirtioPciCap VirtioPciCap; >> >> +int vpci_set_selected_vq(uint16_t queue_num); >> void virtio_pci_id2type(VDev *vdev, uint16_t device_id); >> int virtio_pci_reset(VDev *vdev); >> -long virtio_pci_notify(int vq_id); >> +long virtio_pci_notify(VRing *vr); >> int virtio_pci_setup(VDev *vdev); >> int virtio_pci_setup_device(void); >> >> diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c >> index 30e6b2bc16..00850acc2f 100644 >> --- a/pc-bios/s390-ccw/virtio.c >> +++ b/pc-bios/s390-ccw/virtio.c >> @@ -114,7 +114,8 @@ bool vring_notify(VRing *vr) >> vr->cookie = virtio_ccw_notify(vdev.schid, vr->id, vr->cookie); >> break; >> case S390_IPL_TYPE_PCI: >> - vr->cookie = virtio_pci_notify(vr->id); >> + vr->cookie = virtio_pci_notify(vr); >> + break; >> default: >> return 1; >> } >> @@ -154,6 +155,7 @@ static void vr_bswap_descriptor(VRingDesc *desc) >> void vring_send_buf(VRing *vr, void *p, int len, int flags) >> { >> if (!be_ipl()) { >> + vpci_set_selected_vq(vr->id); >> vr->avail->idx = bswap16(vr->avail->idx); >> } >> >> diff --git a/pc-bios/s390-ccw/virtio.h b/pc-bios/s390-ccw/virtio.h >> index d32a4830ca..75ae5bdbc2 100644 >> --- a/pc-bios/s390-ccw/virtio.h >> +++ b/pc-bios/s390-ccw/virtio.h >> @@ -107,6 +107,7 @@ struct VRing { >> VRingUsed *used; >> long cookie; >> int id; >> + uint16_t pci_notify; >> }; >> typedef struct VRing VRing; >> Regards, Jared Rossi