From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Philippe Brucker Subject: [RFC PATCH v2 2/5] iommu/virtio-iommu: Add probe request Date: Fri, 17 Nov 2017 18:52:08 +0000 Message-ID: <20171117185211.32593-3-jean-philippe.brucker__48891.9817995795$1510944823$gmane$org@arm.com> References: <20171117185211.32593-1-jean-philippe.brucker@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20171117185211.32593-1-jean-philippe.brucker@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: iommu@lists.linux-foundation.org, devel@acpica.org, linux-acpi@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org Cc: Jayachandran.Nair@cavium.com, lorenzo.pieralisi@arm.com, ashok.raj@intel.com, mst@redhat.com, marc.zyngier@arm.com, will.deacon@arm.com, rjw@rjwysocki.net, robert.moore@intel.com, eric.auger@redhat.com, lv.zheng@intel.com, sudeep.holla@arm.com, lenb@kernel.org, robin.murphy@arm.com, joro@8bytes.org, hanjun.guo@linaro.org List-Id: virtualization@lists.linuxfoundation.org When the device offers the probe feature, send a probe request for each device managed by the IOMMU. Extract RESV_MEM information. When we encounter a MSI doorbell region, set it up as a IOMMU_RESV_MSI region. This will tell other subsystems that there is no need to map the MSI doorbell in the virtio-iommu, because MSIs bypass it. Signed-off-by: Jean-Philippe Brucker --- drivers/iommu/virtio-iommu.c | 165 ++++++++++++++++++++++++++++++++++++-- include/uapi/linux/virtio_iommu.h | 37 +++++++++ 2 files changed, 195 insertions(+), 7 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index feb8c8925c3a..79e0add94e05 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -45,6 +45,7 @@ struct viommu_dev { struct iommu_domain_geometry geometry; u64 pgsize_bitmap; u8 domain_bits; + u32 probe_size; }; struct viommu_mapping { @@ -72,6 +73,7 @@ struct viommu_domain { struct viommu_endpoint { struct viommu_dev *viommu; struct viommu_domain *vdomain; + struct list_head resv_regions; }; struct viommu_request { @@ -139,6 +141,10 @@ static int viommu_get_req_size(struct viommu_dev *viommu, case VIRTIO_IOMMU_T_UNMAP: size = sizeof(r->unmap); break; + case VIRTIO_IOMMU_T_PROBE: + *bottom += viommu->probe_size; + size = sizeof(r->probe) + *bottom; + break; default: return -EINVAL; } @@ -448,6 +454,106 @@ static int viommu_replay_mappings(struct viommu_domain *vdomain) return ret; } +static int viommu_add_resv_mem(struct viommu_endpoint *vdev, + struct virtio_iommu_probe_resv_mem *mem, + size_t len) +{ + struct iommu_resv_region *region = NULL; + unsigned long prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; + + u64 addr = le64_to_cpu(mem->addr); + u64 size = le64_to_cpu(mem->size); + + if (len < sizeof(*mem)) + return -EINVAL; + + switch (mem->subtype) { + case VIRTIO_IOMMU_RESV_MEM_T_MSI: + region = iommu_alloc_resv_region(addr, size, prot, + IOMMU_RESV_MSI); + break; + case VIRTIO_IOMMU_RESV_MEM_T_RESERVED: + default: + region = iommu_alloc_resv_region(addr, size, 0, + IOMMU_RESV_RESERVED); + break; + } + + list_add(&vdev->resv_regions, ®ion->list); + + if (mem->subtype != VIRTIO_IOMMU_RESV_MEM_T_RESERVED && + mem->subtype != VIRTIO_IOMMU_RESV_MEM_T_MSI) { + /* Please update your driver. */ + pr_warn("unknown resv mem subtype 0x%x\n", mem->subtype); + return -EINVAL; + } + + return 0; +} + +static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev) +{ + int ret; + u16 type, len; + size_t cur = 0; + struct virtio_iommu_req_probe *probe; + struct virtio_iommu_probe_property *prop; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + struct viommu_endpoint *vdev = fwspec->iommu_priv; + + if (!fwspec->num_ids) + /* Trouble ahead. */ + return -EINVAL; + + probe = kzalloc(sizeof(*probe) + viommu->probe_size + + sizeof(struct virtio_iommu_req_tail), GFP_KERNEL); + if (!probe) + return -ENOMEM; + + probe->head.type = VIRTIO_IOMMU_T_PROBE; + /* + * For now, assume that properties of an endpoint that outputs multiple + * IDs are consistent. Only probe the first one. + */ + probe->endpoint = cpu_to_le32(fwspec->ids[0]); + + ret = viommu_send_req_sync(viommu, probe); + if (ret) { + kfree(probe); + return ret; + } + + prop = (void *)probe->properties; + type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK; + + while (type != VIRTIO_IOMMU_PROBE_T_NONE && + cur < viommu->probe_size) { + len = le16_to_cpu(prop->length); + + switch (type) { + case VIRTIO_IOMMU_PROBE_T_RESV_MEM: + ret = viommu_add_resv_mem(vdev, (void *)prop->value, len); + break; + default: + dev_dbg(dev, "unknown viommu prop 0x%x\n", type); + } + + if (ret) + dev_err(dev, "failed to parse viommu prop 0x%x\n", type); + + cur += sizeof(*prop) + len; + if (cur >= viommu->probe_size) + break; + + prop = (void *)probe->properties + cur; + type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK; + } + + kfree(probe); + + return 0; +} + /* IOMMU API */ static bool viommu_capable(enum iommu_cap cap) @@ -706,6 +812,7 @@ static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode) static int viommu_add_device(struct device *dev) { + int ret; struct iommu_group *group; struct viommu_endpoint *vdev; struct viommu_dev *viommu = NULL; @@ -723,8 +830,16 @@ static int viommu_add_device(struct device *dev) return -ENOMEM; vdev->viommu = viommu; + INIT_LIST_HEAD(&vdev->resv_regions); fwspec->iommu_priv = vdev; + if (viommu->probe_size) { + /* Get additional information for this endpoint */ + ret = viommu_probe_endpoint(viommu, dev); + if (ret) + return ret; + } + /* * Last step creates a default domain and attaches to it. Everything * must be ready. @@ -738,7 +853,19 @@ static int viommu_add_device(struct device *dev) static void viommu_remove_device(struct device *dev) { - kfree(dev->iommu_fwspec->iommu_priv); + struct viommu_endpoint *vdev; + struct iommu_resv_region *entry, *next; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + + if (!fwspec || fwspec->ops != &viommu_ops) + return; + + vdev = fwspec->iommu_priv; + + list_for_each_entry_safe(entry, next, &vdev->resv_regions, list) + kfree(entry); + + kfree(vdev); } static struct iommu_group *viommu_device_group(struct device *dev) @@ -756,15 +883,34 @@ static int viommu_of_xlate(struct device *dev, struct of_phandle_args *args) static void viommu_get_resv_regions(struct device *dev, struct list_head *head) { - struct iommu_resv_region *region; + struct iommu_resv_region *entry, *new_entry, *msi = NULL; + struct viommu_endpoint *vdev = dev->iommu_fwspec->iommu_priv; int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; - region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, prot, - IOMMU_RESV_SW_MSI); - if (!region) - return; + list_for_each_entry(entry, &vdev->resv_regions, list) { + /* + * If the device registered a bypass MSI windows, use it. + * Otherwise add a software-mapped region + */ + if (entry->type == IOMMU_RESV_MSI) + msi = entry; + + new_entry = kmemdup(entry, sizeof(*entry), GFP_KERNEL); + if (!new_entry) + return; + list_add_tail(&new_entry->list, head); + } - list_add_tail(®ion->list, head); + if (!msi) { + msi = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, + prot, IOMMU_RESV_SW_MSI); + if (!msi) + return; + + list_add_tail(&msi->list, head); + } + + iommu_dma_get_resv_regions(dev, head); } static void viommu_put_resv_regions(struct device *dev, struct list_head *head) @@ -854,6 +1000,10 @@ static int viommu_probe(struct virtio_device *vdev) struct virtio_iommu_config, domain_bits, &viommu->domain_bits); + virtio_cread_feature(vdev, VIRTIO_IOMMU_F_PROBE, + struct virtio_iommu_config, probe_size, + &viommu->probe_size); + viommu->geometry = (struct iommu_domain_geometry) { .aperture_start = input_start, .aperture_end = input_end, @@ -931,6 +1081,7 @@ static unsigned int features[] = { VIRTIO_IOMMU_F_MAP_UNMAP, VIRTIO_IOMMU_F_DOMAIN_BITS, VIRTIO_IOMMU_F_INPUT_RANGE, + VIRTIO_IOMMU_F_PROBE, }; static struct virtio_device_id id_table[] = { diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h index 2b4cd2042897..eec90a2ab547 100644 --- a/include/uapi/linux/virtio_iommu.h +++ b/include/uapi/linux/virtio_iommu.h @@ -38,6 +38,7 @@ #define VIRTIO_IOMMU_F_DOMAIN_BITS 1 #define VIRTIO_IOMMU_F_MAP_UNMAP 2 #define VIRTIO_IOMMU_F_BYPASS 3 +#define VIRTIO_IOMMU_F_PROBE 4 struct virtio_iommu_config { /* Supported page sizes */ @@ -49,6 +50,9 @@ struct virtio_iommu_config { } input_range; /* Max domain ID size */ __u8 domain_bits; + __u8 padding[3]; + /* Probe buffer size */ + __u32 probe_size; } __packed; /* Request types */ @@ -56,6 +60,7 @@ struct virtio_iommu_config { #define VIRTIO_IOMMU_T_DETACH 0x02 #define VIRTIO_IOMMU_T_MAP 0x03 #define VIRTIO_IOMMU_T_UNMAP 0x04 +#define VIRTIO_IOMMU_T_PROBE 0x05 /* Status types */ #define VIRTIO_IOMMU_S_OK 0x00 @@ -128,6 +133,37 @@ struct virtio_iommu_req_unmap { struct virtio_iommu_req_tail tail; } __packed; +#define VIRTIO_IOMMU_RESV_MEM_T_RESERVED 0 +#define VIRTIO_IOMMU_RESV_MEM_T_MSI 1 + +struct virtio_iommu_probe_resv_mem { + __u8 subtype; + __u8 reserved[3]; + __le64 addr; + __le64 size; +} __packed; + +#define VIRTIO_IOMMU_PROBE_T_NONE 0 +#define VIRTIO_IOMMU_PROBE_T_RESV_MEM 1 + +#define VIRTIO_IOMMU_PROBE_T_MASK 0xfff + +struct virtio_iommu_probe_property { + __le16 type; + __le16 length; + __u8 value[]; +} __packed; + +struct virtio_iommu_req_probe { + struct virtio_iommu_req_head head; + __le32 endpoint; + __u8 reserved[64]; + + __u8 properties[]; + + /* Tail follows the variable-length properties array (no padding) */ +} __packed; + union virtio_iommu_req { struct virtio_iommu_req_head head; @@ -135,6 +171,7 @@ union virtio_iommu_req { struct virtio_iommu_req_detach detach; struct virtio_iommu_req_map map; struct virtio_iommu_req_unmap unmap; + struct virtio_iommu_req_probe probe; }; #endif -- 2.14.3