From 5456b1867d10826e3857fda417b59a669fa5cce9 Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Mon, 9 Oct 2023 11:09:09 +0200 Subject: [PATCH] vfio/pci: Introduce vfio_[attach/detach]_device MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We want the VFIO devices to be able to use two different IOMMU backends, the legacy VFIO one and the new iommufd one. Introduce vfio_[attach/detach]_device which aim at hiding the underlying IOMMU backend (IOCTLs, datatypes, ...). Once vfio_attach_device completes, the device is attached to a security context and its fd can be used. Conversely When vfio_detach_device completes, the device has been detached from the security context. At the moment only the implementation based on the legacy container/group exists. Let's use it from the vfio-pci device. Subsequent patches will handle other devices. We also take benefit of this patch to properly free vbasedev->name on failure. Signed-off-by: Eric Auger Signed-off-by: Yi Liu Signed-off-by: Zhenzhong Duan Reviewed-by: Cédric Le Goater Signed-off-by: Cédric Le Goater --- hw/vfio/common.c | 74 +++++++++++++++++++++++++++++++++++ hw/vfio/pci.c | 66 +++++++------------------------ hw/vfio/trace-events | 3 +- include/hw/vfio/vfio-common.h | 3 ++ 4 files changed, 93 insertions(+), 53 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index d8ed432cb6..f4c33c9858 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -2611,3 +2611,77 @@ int vfio_eeh_as_op(AddressSpace *as, uint32_t op) } return vfio_eeh_container_op(container, op); } + +static int vfio_device_groupid(VFIODevice *vbasedev, Error **errp) +{ + char *tmp, group_path[PATH_MAX], *group_name; + int ret, groupid; + ssize_t len; + + tmp = g_strdup_printf("%s/iommu_group", vbasedev->sysfsdev); + len = readlink(tmp, group_path, sizeof(group_path)); + g_free(tmp); + + if (len <= 0 || len >= sizeof(group_path)) { + ret = len < 0 ? -errno : -ENAMETOOLONG; + error_setg_errno(errp, -ret, "no iommu_group found"); + return ret; + } + + group_path[len] = 0; + + group_name = basename(group_path); + if (sscanf(group_name, "%d", &groupid) != 1) { + error_setg_errno(errp, errno, "failed to read %s", group_path); + return -errno; + } + return groupid; +} + +/* + * vfio_attach_device: attach a device to a security context + * @name and @vbasedev->name are likely to be different depending + * on the type of the device, hence the need for passing @name + */ +int vfio_attach_device(char *name, VFIODevice *vbasedev, + AddressSpace *as, Error **errp) +{ + int groupid = vfio_device_groupid(vbasedev, errp); + VFIODevice *vbasedev_iter; + VFIOGroup *group; + int ret; + + if (groupid < 0) { + return groupid; + } + + trace_vfio_attach_device(vbasedev->name, groupid); + + group = vfio_get_group(groupid, as, errp); + if (!group) { + return -ENOENT; + } + + QLIST_FOREACH(vbasedev_iter, &group->device_list, next) { + if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) { + error_setg(errp, "device is already attached"); + vfio_put_group(group); + return -EBUSY; + } + } + ret = vfio_get_device(group, name, vbasedev, errp); + if (ret) { + vfio_put_group(group); + } + + return ret; +} + +void vfio_detach_device(VFIODevice *vbasedev) +{ + VFIOGroup *group = vbasedev->group; + + trace_vfio_detach_device(vbasedev->name, group->groupid); + vfio_put_base_device(vbasedev); + vfio_put_group(group); +} diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 898296fd54..40ae46266e 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -2895,10 +2895,10 @@ static void vfio_populate_device(VFIOPCIDevice *vdev, Error **errp) static void vfio_pci_put_device(VFIOPCIDevice *vdev) { + vfio_detach_device(&vdev->vbasedev); + g_free(vdev->vbasedev.name); g_free(vdev->msix); - - vfio_put_base_device(&vdev->vbasedev); } static void vfio_err_notifier_handler(void *opaque) @@ -3045,13 +3045,9 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) { VFIOPCIDevice *vdev = VFIO_PCI(pdev); VFIODevice *vbasedev = &vdev->vbasedev; - VFIODevice *vbasedev_iter; - VFIOGroup *group; - char *tmp, *subsys, group_path[PATH_MAX], *group_name; + char *tmp, *subsys; Error *err = NULL; - ssize_t len; struct stat st; - int groupid; int i, ret; bool is_mdev; char uuid[UUID_FMT_LEN]; @@ -3082,39 +3078,6 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) vbasedev->type = VFIO_DEVICE_TYPE_PCI; vbasedev->dev = DEVICE(vdev); - tmp = g_strdup_printf("%s/iommu_group", vbasedev->sysfsdev); - len = readlink(tmp, group_path, sizeof(group_path)); - g_free(tmp); - - if (len <= 0 || len >= sizeof(group_path)) { - error_setg_errno(errp, len < 0 ? errno : ENAMETOOLONG, - "no iommu_group found"); - goto error; - } - - group_path[len] = 0; - - group_name = basename(group_path); - if (sscanf(group_name, "%d", &groupid) != 1) { - error_setg_errno(errp, errno, "failed to read %s", group_path); - goto error; - } - - trace_vfio_realize(vbasedev->name, groupid); - - group = vfio_get_group(groupid, pci_device_iommu_address_space(pdev), errp); - if (!group) { - goto error; - } - - QLIST_FOREACH(vbasedev_iter, &group->device_list, next) { - if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) { - error_setg(errp, "device is already attached"); - vfio_put_group(group); - goto error; - } - } - /* * Mediated devices *might* operate compatibly with discarding of RAM, but * we cannot know for certain, it depends on whether the mdev vendor driver @@ -3132,7 +3095,6 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) if (vbasedev->ram_block_discard_allowed && !is_mdev) { error_setg(errp, "x-balloon-allowed only potentially compatible " "with mdev devices"); - vfio_put_group(group); goto error; } @@ -3143,17 +3105,17 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) name = g_strdup(vbasedev->name); } - ret = vfio_get_device(group, name, vbasedev, errp); + ret = vfio_attach_device(name, vbasedev, + pci_device_iommu_address_space(pdev), errp); g_free(name); if (ret) { - vfio_put_group(group); goto error; } vfio_populate_device(vdev, &err); if (err) { error_propagate(errp, err); - goto error; + goto out_detach; } /* Get a copy of config space */ @@ -3163,7 +3125,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) if (ret < (int)MIN(pci_config_size(&vdev->pdev), vdev->config_size)) { ret = ret < 0 ? -errno : -EFAULT; error_setg_errno(errp, -ret, "failed to read device config space"); - goto error; + goto out_detach; } /* vfio emulates a lot for us, but some bits need extra love */ @@ -3182,7 +3144,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) if (vdev->vendor_id != PCI_ANY_ID) { if (vdev->vendor_id >= 0xffff) { error_setg(errp, "invalid PCI vendor ID provided"); - goto error; + goto out_detach; } vfio_add_emulated_word(vdev, PCI_VENDOR_ID, vdev->vendor_id, ~0); trace_vfio_pci_emulated_vendor_id(vbasedev->name, vdev->vendor_id); @@ -3193,7 +3155,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) if (vdev->device_id != PCI_ANY_ID) { if (vdev->device_id > 0xffff) { error_setg(errp, "invalid PCI device ID provided"); - goto error; + goto out_detach; } vfio_add_emulated_word(vdev, PCI_DEVICE_ID, vdev->device_id, ~0); trace_vfio_pci_emulated_device_id(vbasedev->name, vdev->device_id); @@ -3204,7 +3166,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) if (vdev->sub_vendor_id != PCI_ANY_ID) { if (vdev->sub_vendor_id > 0xffff) { error_setg(errp, "invalid PCI subsystem vendor ID provided"); - goto error; + goto out_detach; } vfio_add_emulated_word(vdev, PCI_SUBSYSTEM_VENDOR_ID, vdev->sub_vendor_id, ~0); @@ -3215,7 +3177,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) if (vdev->sub_device_id != PCI_ANY_ID) { if (vdev->sub_device_id > 0xffff) { error_setg(errp, "invalid PCI subsystem device ID provided"); - goto error; + goto out_detach; } vfio_add_emulated_word(vdev, PCI_SUBSYSTEM_ID, vdev->sub_device_id, ~0); trace_vfio_pci_emulated_sub_device_id(vbasedev->name, @@ -3248,7 +3210,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp) vfio_msix_early_setup(vdev, &err); if (err) { error_propagate(errp, err); - goto error; + goto out_detach; } vfio_bars_register(vdev); @@ -3364,6 +3326,8 @@ out_deregister: out_teardown: vfio_teardown_msi(vdev); vfio_bars_exit(vdev); +out_detach: + vfio_detach_device(vbasedev); error: error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->name); } @@ -3371,7 +3335,6 @@ error: static void vfio_instance_finalize(Object *obj) { VFIOPCIDevice *vdev = VFIO_PCI(obj); - VFIOGroup *group = vdev->vbasedev.group; vfio_display_finalize(vdev); vfio_bars_finalize(vdev); @@ -3385,7 +3348,6 @@ static void vfio_instance_finalize(Object *obj) * g_free(vdev->igd_opregion); */ vfio_pci_put_device(vdev); - vfio_put_group(group); } static void vfio_exitfn(PCIDevice *pdev) diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events index 0ba3c5a0e2..8ac13eb106 100644 --- a/hw/vfio/trace-events +++ b/hw/vfio/trace-events @@ -37,7 +37,8 @@ vfio_pci_hot_reset_dep_devices(int domain, int bus, int slot, int function, int vfio_pci_hot_reset_result(const char *name, const char *result) "%s hot reset: %s" vfio_populate_device_config(const char *name, unsigned long size, unsigned long offset, unsigned long flags) "Device %s config:\n size: 0x%lx, offset: 0x%lx, flags: 0x%lx" vfio_populate_device_get_irq_info_failure(const char *errstr) "VFIO_DEVICE_GET_IRQ_INFO failure: %s" -vfio_realize(const char *name, int group_id) " (%s) group %d" +vfio_attach_device(const char *name, int group_id) " (%s) group %d" +vfio_detach_device(const char *name, int group_id) " (%s) group %d" vfio_mdev(const char *name, bool is_mdev) " (%s) is_mdev %d" vfio_add_ext_cap_dropped(const char *name, uint16_t cap, uint16_t offset) "%s 0x%x@0x%x" vfio_pci_reset(const char *name) " (%s)" diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index c4e7c3b4a7..12fbfbc37d 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -225,6 +225,9 @@ void vfio_put_group(VFIOGroup *group); struct vfio_device_info *vfio_get_device_info(int fd); int vfio_get_device(VFIOGroup *group, const char *name, VFIODevice *vbasedev, Error **errp); +int vfio_attach_device(char *name, VFIODevice *vbasedev, + AddressSpace *as, Error **errp); +void vfio_detach_device(VFIODevice *vbasedev); int vfio_kvm_device_add_fd(int fd, Error **errp); int vfio_kvm_device_del_fd(int fd, Error **errp);