> -----Original Message----- > From: Jason Gunthorpe [mailto:jgg@xxxxxxxxxx] > Sent: 08 February 2022 15:22 > To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@xxxxxxxxxx> > Cc: kvm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > linux-crypto@xxxxxxxxxxxxxxx; alex.williamson@xxxxxxxxxx; > cohuck@xxxxxxxxxx; mgurtovoy@xxxxxxxxxx; yishaih@xxxxxxxxxx; Linuxarm > <linuxarm@xxxxxxxxxx>; liulongfang <liulongfang@xxxxxxxxxx>; Zengtao (B) > <prime.zeng@xxxxxxxxxxxxx>; Jonathan Cameron > <jonathan.cameron@xxxxxxxxxx>; Wangzhou (B) <wangzhou1@xxxxxxxxxxxxx> > Subject: Re: [RFC v4 7/8] hisi_acc_vfio_pci: Add support for VFIO live > migration > > On Tue, Feb 08, 2022 at 01:34:24PM +0000, Shameer Kolothum wrote: > > Overall this looks like a fine implementation, as far as I can tell it > meets the uAPI design perfectly. > > Why did you decide not to do the P2P support? I need to check that with our hardware folks. May be it is in pipeline. > > +static struct file * > > +hisi_acc_vf_set_device_state(struct hisi_acc_vf_core_device *hisi_acc_vdev, > > + u32 new) > > +{ > > + u32 cur = hisi_acc_vdev->mig_state; > > + int ret; > > + > > + if (cur == VFIO_DEVICE_STATE_RUNNING && new == > VFIO_DEVICE_STATE_STOP) { > > + ret = hisi_acc_vf_stop_device(hisi_acc_vdev); > > + if (ret) > > + return ERR_PTR(ret); > > Be mindful that qemu doesn't handle a failure here very well, I'm not > sure we will be able to fix this in the short term. Ok. I will check that and see how big of a problem it is. > > +static int hisi_acc_vfio_pci_init(struct hisi_acc_vf_core_device > *hisi_acc_vdev) > > +{ > > + struct vfio_pci_core_device *vdev = &hisi_acc_vdev->core_device; > > + struct pci_dev *vf_dev = vdev->pdev; > > + struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm; > > + > > + /* > > + * ACC VF dev BAR2 region consists of both functional register space > > + * and migration control register space. For migration to work, we > > + * need access to both. Hence, we map the entire BAR2 region here. > > + * But from a security point of view, we restrict access to the > > + * migration control space from Guest(Please see mmap/ioctl/read/write > > + * override functions). > > + * > > + * Also the HiSilicon ACC VF devices supported by this driver on > > + * HiSilicon hardware platforms are integrated end point devices > > + * and has no capability to perform PCIe P2P. > > + */ > > + vf_qm->io_base = > > + ioremap(pci_resource_start(vf_dev, VFIO_PCI_BAR2_REGION_INDEX), > > + pci_resource_len(vf_dev, VFIO_PCI_BAR2_REGION_INDEX)); > > + if (!vf_qm->io_base) > > + return -EIO; > > + > > + vf_qm->fun_type = QM_HW_VF; > > + vf_qm->pdev = vf_dev; > > + mutex_init(&vf_qm->mailbox_lock); > > mailbox_lock seems unused I think we need that as that will be used in the QM driver APIs. I will add a comment here. > > + hisi_acc_vdev->vf_id = PCI_FUNC(vf_dev->devfn); > > Does this need to use the pci_iov_vf_id() function? funcs don't need > to be tightly packed, necessarily. > > This should be set when the structure is allocated, not at open time. Ok. I will change and move it. > > + hisi_acc_vdev->vf_dev = vf_dev; > > + vf_qm->dev_name = hisi_acc_vdev->pf_qm->dev_name; > > Also unused I will see if we can get rid of it if it is not used by QM driver APIs used here. > > > + hisi_acc_vdev->mig_state = VFIO_DEVICE_STATE_RUNNING; > > + > > + return 0; > > +} > > > > static int hisi_acc_pci_rw_access_check(struct vfio_device *core_vdev, > > size_t count, loff_t *ppos, > > @@ -129,63 +1067,96 @@ static long hisi_acc_vfio_pci_ioctl(struct > vfio_device *core_vdev, unsigned int > > > > static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev) > > { > > - struct vfio_pci_core_device *vdev = > > - container_of(core_vdev, struct vfio_pci_core_device, vdev); > > + struct hisi_acc_vf_core_device *hisi_acc_vdev = container_of(core_vdev, > > + struct hisi_acc_vf_core_device, core_device.vdev); > > + struct vfio_pci_core_device *vdev = &hisi_acc_vdev->core_device; > > int ret; > > > > ret = vfio_pci_core_enable(vdev); > > if (ret) > > return ret; > > > > - vfio_pci_core_finish_enable(vdev); > > + if (!hisi_acc_vdev->migration_support) { > > This should just test the core flag and get rid of migration_support: Ok. > > hisi_acc_vdev->core_device.vdev.migration_flags = > VFIO_MIGRATION_STOP_COPY; > > > +++ b/drivers/vfio/pci/hisi_acc_vfio_pci.h > > @@ -0,0 +1,119 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* Copyright (c) 2021 HiSilicon Ltd. */ > > + > > +#ifndef HISI_ACC_VFIO_PCI_H > > +#define HISI_ACC_VFIO_PCI_H > > + > > +#include <linux/hisi_acc_qm.h> > > + > > +#define VDM_OFFSET(x) offsetof(struct vfio_device_migration_info, x) > > + > > +#define HISI_ACC_MIG_REGION_DATA_OFFSET \ > > + (sizeof(struct vfio_device_migration_info)) > > + > > +#define HISI_ACC_MIG_REGION_DATA_SIZE (sizeof(struct acc_vf_data)) > > These three are not used any more True. > > > +struct acc_vf_data { > > +#define QM_MATCH_SIZE 32L > > + /* QM match information */ > > + u32 qp_num; > > + u32 dev_id; > > + u32 que_iso_cfg; > > + u32 qp_base; > > + /* QM reserved 4 match information */ > > + u32 qm_rsv_state[4]; > > + > > + /* QM RW regs */ > > + u32 aeq_int_mask; > > + u32 eq_int_mask; > > + u32 ifc_int_source; > > + u32 ifc_int_mask; > > + u32 ifc_int_set; > > + u32 page_size; > > + > > + /* QM_EQC_DW has 7 regs */ > > + u32 qm_eqc_dw[7]; > > + > > + /* QM_AEQC_DW has 7 regs */ > > + u32 qm_aeqc_dw[7]; > > + > > + /* QM reserved 5 regs */ > > + u32 qm_rsv_regs[5]; > > + > > + /* qm memory init information */ > > + dma_addr_t eqe_dma; > > + dma_addr_t aeqe_dma; > > + dma_addr_t sqc_dma; > > + dma_addr_t cqc_dma; > > You can't put dma_addr_t in a structure that needs to go > on-the-wire. This should be u64 Ok. Thanks, Shameer > > +}; > > + > > +struct hisi_acc_vf_migration_file { > > + struct file *filp; > > + struct mutex lock; > > + bool disabled; > > + > > + struct acc_vf_data vf_data; > > + size_t total_length; > > +}; > > + > > +struct hisi_acc_vf_core_device { > > + struct vfio_pci_core_device core_device; > > + u8 migration_support:1; > > + /* for migration state */ > > + struct mutex state_mutex; > > + enum vfio_device_mig_state mig_state; > > + struct pci_dev *pf_dev; > > + struct pci_dev *vf_dev; > > + struct hisi_qm *pf_qm; > > + struct hisi_qm vf_qm; > > + int vf_id; > > + > > + struct hisi_acc_vf_migration_file *resuming_migf; > > + struct hisi_acc_vf_migration_file *saving_migf; > > +}; > > +#endif /* HISI_ACC_VFIO_PCI_H */
