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1158 lines
29 KiB
1158 lines
29 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Virtio driver for the paravirtualized IOMMU |
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* |
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* Copyright (C) 2019 Arm Limited |
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*/ |
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|
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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|
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#include <linux/amba/bus.h> |
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#include <linux/delay.h> |
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#include <linux/dma-iommu.h> |
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#include <linux/freezer.h> |
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#include <linux/interval_tree.h> |
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#include <linux/iommu.h> |
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#include <linux/module.h> |
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#include <linux/of_iommu.h> |
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#include <linux/of_platform.h> |
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#include <linux/pci.h> |
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#include <linux/platform_device.h> |
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#include <linux/virtio.h> |
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#include <linux/virtio_config.h> |
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#include <linux/virtio_ids.h> |
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#include <linux/wait.h> |
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|
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#include <uapi/linux/virtio_iommu.h> |
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|
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#define MSI_IOVA_BASE 0x8000000 |
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#define MSI_IOVA_LENGTH 0x100000 |
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|
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#define VIOMMU_REQUEST_VQ 0 |
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#define VIOMMU_EVENT_VQ 1 |
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#define VIOMMU_NR_VQS 2 |
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struct viommu_dev { |
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struct iommu_device iommu; |
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struct device *dev; |
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struct virtio_device *vdev; |
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|
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struct ida domain_ids; |
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|
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struct virtqueue *vqs[VIOMMU_NR_VQS]; |
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spinlock_t request_lock; |
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struct list_head requests; |
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void *evts; |
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|
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/* Device configuration */ |
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struct iommu_domain_geometry geometry; |
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u64 pgsize_bitmap; |
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u32 first_domain; |
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u32 last_domain; |
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/* Supported MAP flags */ |
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u32 map_flags; |
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u32 probe_size; |
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}; |
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|
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struct viommu_mapping { |
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phys_addr_t paddr; |
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struct interval_tree_node iova; |
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u32 flags; |
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}; |
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struct viommu_domain { |
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struct iommu_domain domain; |
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struct viommu_dev *viommu; |
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struct mutex mutex; /* protects viommu pointer */ |
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unsigned int id; |
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u32 map_flags; |
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spinlock_t mappings_lock; |
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struct rb_root_cached mappings; |
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|
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unsigned long nr_endpoints; |
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}; |
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|
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struct viommu_endpoint { |
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struct device *dev; |
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struct viommu_dev *viommu; |
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struct viommu_domain *vdomain; |
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struct list_head resv_regions; |
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}; |
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struct viommu_request { |
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struct list_head list; |
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void *writeback; |
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unsigned int write_offset; |
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unsigned int len; |
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char buf[]; |
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}; |
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#define VIOMMU_FAULT_RESV_MASK 0xffffff00 |
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struct viommu_event { |
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union { |
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u32 head; |
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struct virtio_iommu_fault fault; |
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}; |
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}; |
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|
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#define to_viommu_domain(domain) \ |
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container_of(domain, struct viommu_domain, domain) |
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static int viommu_get_req_errno(void *buf, size_t len) |
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{ |
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struct virtio_iommu_req_tail *tail = buf + len - sizeof(*tail); |
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|
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switch (tail->status) { |
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case VIRTIO_IOMMU_S_OK: |
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return 0; |
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case VIRTIO_IOMMU_S_UNSUPP: |
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return -ENOSYS; |
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case VIRTIO_IOMMU_S_INVAL: |
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return -EINVAL; |
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case VIRTIO_IOMMU_S_RANGE: |
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return -ERANGE; |
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case VIRTIO_IOMMU_S_NOENT: |
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return -ENOENT; |
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case VIRTIO_IOMMU_S_FAULT: |
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return -EFAULT; |
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case VIRTIO_IOMMU_S_NOMEM: |
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return -ENOMEM; |
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case VIRTIO_IOMMU_S_IOERR: |
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case VIRTIO_IOMMU_S_DEVERR: |
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default: |
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return -EIO; |
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} |
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} |
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|
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static void viommu_set_req_status(void *buf, size_t len, int status) |
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{ |
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struct virtio_iommu_req_tail *tail = buf + len - sizeof(*tail); |
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|
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tail->status = status; |
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} |
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static off_t viommu_get_write_desc_offset(struct viommu_dev *viommu, |
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struct virtio_iommu_req_head *req, |
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size_t len) |
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{ |
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size_t tail_size = sizeof(struct virtio_iommu_req_tail); |
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|
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if (req->type == VIRTIO_IOMMU_T_PROBE) |
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return len - viommu->probe_size - tail_size; |
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|
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return len - tail_size; |
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} |
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/* |
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* __viommu_sync_req - Complete all in-flight requests |
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* |
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* Wait for all added requests to complete. When this function returns, all |
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* requests that were in-flight at the time of the call have completed. |
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*/ |
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static int __viommu_sync_req(struct viommu_dev *viommu) |
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{ |
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unsigned int len; |
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size_t write_len; |
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struct viommu_request *req; |
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struct virtqueue *vq = viommu->vqs[VIOMMU_REQUEST_VQ]; |
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assert_spin_locked(&viommu->request_lock); |
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virtqueue_kick(vq); |
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|
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while (!list_empty(&viommu->requests)) { |
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len = 0; |
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req = virtqueue_get_buf(vq, &len); |
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if (!req) |
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continue; |
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|
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if (!len) |
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viommu_set_req_status(req->buf, req->len, |
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VIRTIO_IOMMU_S_IOERR); |
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|
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write_len = req->len - req->write_offset; |
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if (req->writeback && len == write_len) |
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memcpy(req->writeback, req->buf + req->write_offset, |
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write_len); |
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list_del(&req->list); |
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kfree(req); |
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} |
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return 0; |
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} |
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static int viommu_sync_req(struct viommu_dev *viommu) |
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{ |
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int ret; |
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unsigned long flags; |
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|
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spin_lock_irqsave(&viommu->request_lock, flags); |
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ret = __viommu_sync_req(viommu); |
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if (ret) |
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dev_dbg(viommu->dev, "could not sync requests (%d)\n", ret); |
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spin_unlock_irqrestore(&viommu->request_lock, flags); |
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return ret; |
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} |
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|
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/* |
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* __viommu_add_request - Add one request to the queue |
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* @buf: pointer to the request buffer |
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* @len: length of the request buffer |
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* @writeback: copy data back to the buffer when the request completes. |
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* |
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* Add a request to the queue. Only synchronize the queue if it's already full. |
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* Otherwise don't kick the queue nor wait for requests to complete. |
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* |
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* When @writeback is true, data written by the device, including the request |
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* status, is copied into @buf after the request completes. This is unsafe if |
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* the caller allocates @buf on stack and drops the lock between add_req() and |
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* sync_req(). |
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* |
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* Return 0 if the request was successfully added to the queue. |
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*/ |
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static int __viommu_add_req(struct viommu_dev *viommu, void *buf, size_t len, |
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bool writeback) |
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{ |
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int ret; |
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off_t write_offset; |
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struct viommu_request *req; |
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struct scatterlist top_sg, bottom_sg; |
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struct scatterlist *sg[2] = { &top_sg, &bottom_sg }; |
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struct virtqueue *vq = viommu->vqs[VIOMMU_REQUEST_VQ]; |
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assert_spin_locked(&viommu->request_lock); |
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write_offset = viommu_get_write_desc_offset(viommu, buf, len); |
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if (write_offset <= 0) |
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return -EINVAL; |
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req = kzalloc(sizeof(*req) + len, GFP_ATOMIC); |
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if (!req) |
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return -ENOMEM; |
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req->len = len; |
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if (writeback) { |
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req->writeback = buf + write_offset; |
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req->write_offset = write_offset; |
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} |
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memcpy(&req->buf, buf, write_offset); |
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|
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sg_init_one(&top_sg, req->buf, write_offset); |
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sg_init_one(&bottom_sg, req->buf + write_offset, len - write_offset); |
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ret = virtqueue_add_sgs(vq, sg, 1, 1, req, GFP_ATOMIC); |
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if (ret == -ENOSPC) { |
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/* If the queue is full, sync and retry */ |
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if (!__viommu_sync_req(viommu)) |
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ret = virtqueue_add_sgs(vq, sg, 1, 1, req, GFP_ATOMIC); |
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} |
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if (ret) |
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goto err_free; |
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list_add_tail(&req->list, &viommu->requests); |
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return 0; |
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err_free: |
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kfree(req); |
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return ret; |
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} |
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static int viommu_add_req(struct viommu_dev *viommu, void *buf, size_t len) |
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{ |
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int ret; |
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unsigned long flags; |
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spin_lock_irqsave(&viommu->request_lock, flags); |
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ret = __viommu_add_req(viommu, buf, len, false); |
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if (ret) |
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dev_dbg(viommu->dev, "could not add request: %d\n", ret); |
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spin_unlock_irqrestore(&viommu->request_lock, flags); |
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return ret; |
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} |
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|
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/* |
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* Send a request and wait for it to complete. Return the request status (as an |
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* errno) |
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*/ |
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static int viommu_send_req_sync(struct viommu_dev *viommu, void *buf, |
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size_t len) |
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{ |
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int ret; |
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unsigned long flags; |
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spin_lock_irqsave(&viommu->request_lock, flags); |
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ret = __viommu_add_req(viommu, buf, len, true); |
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if (ret) { |
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dev_dbg(viommu->dev, "could not add request (%d)\n", ret); |
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goto out_unlock; |
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} |
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|
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ret = __viommu_sync_req(viommu); |
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if (ret) { |
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dev_dbg(viommu->dev, "could not sync requests (%d)\n", ret); |
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/* Fall-through (get the actual request status) */ |
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} |
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|
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ret = viommu_get_req_errno(buf, len); |
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out_unlock: |
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spin_unlock_irqrestore(&viommu->request_lock, flags); |
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return ret; |
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} |
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/* |
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* viommu_add_mapping - add a mapping to the internal tree |
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* |
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* On success, return the new mapping. Otherwise return NULL. |
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*/ |
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static int viommu_add_mapping(struct viommu_domain *vdomain, unsigned long iova, |
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phys_addr_t paddr, size_t size, u32 flags) |
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{ |
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unsigned long irqflags; |
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struct viommu_mapping *mapping; |
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|
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mapping = kzalloc(sizeof(*mapping), GFP_ATOMIC); |
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if (!mapping) |
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return -ENOMEM; |
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mapping->paddr = paddr; |
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mapping->iova.start = iova; |
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mapping->iova.last = iova + size - 1; |
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mapping->flags = flags; |
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|
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spin_lock_irqsave(&vdomain->mappings_lock, irqflags); |
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interval_tree_insert(&mapping->iova, &vdomain->mappings); |
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spin_unlock_irqrestore(&vdomain->mappings_lock, irqflags); |
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|
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return 0; |
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} |
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/* |
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* viommu_del_mappings - remove mappings from the internal tree |
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* |
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* @vdomain: the domain |
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* @iova: start of the range |
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* @size: size of the range. A size of 0 corresponds to the entire address |
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* space. |
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* |
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* On success, returns the number of unmapped bytes (>= size) |
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*/ |
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static size_t viommu_del_mappings(struct viommu_domain *vdomain, |
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unsigned long iova, size_t size) |
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{ |
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size_t unmapped = 0; |
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unsigned long flags; |
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unsigned long last = iova + size - 1; |
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struct viommu_mapping *mapping = NULL; |
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struct interval_tree_node *node, *next; |
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|
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spin_lock_irqsave(&vdomain->mappings_lock, flags); |
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next = interval_tree_iter_first(&vdomain->mappings, iova, last); |
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while (next) { |
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node = next; |
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mapping = container_of(node, struct viommu_mapping, iova); |
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next = interval_tree_iter_next(node, iova, last); |
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|
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/* Trying to split a mapping? */ |
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if (mapping->iova.start < iova) |
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break; |
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|
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/* |
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* Virtio-iommu doesn't allow UNMAP to split a mapping created |
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* with a single MAP request, so remove the full mapping. |
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*/ |
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unmapped += mapping->iova.last - mapping->iova.start + 1; |
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|
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interval_tree_remove(node, &vdomain->mappings); |
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kfree(mapping); |
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} |
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spin_unlock_irqrestore(&vdomain->mappings_lock, flags); |
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|
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return unmapped; |
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} |
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|
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/* |
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* viommu_replay_mappings - re-send MAP requests |
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* |
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* When reattaching a domain that was previously detached from all endpoints, |
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* mappings were deleted from the device. Re-create the mappings available in |
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* the internal tree. |
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*/ |
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static int viommu_replay_mappings(struct viommu_domain *vdomain) |
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{ |
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int ret = 0; |
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unsigned long flags; |
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struct viommu_mapping *mapping; |
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struct interval_tree_node *node; |
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struct virtio_iommu_req_map map; |
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|
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spin_lock_irqsave(&vdomain->mappings_lock, flags); |
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node = interval_tree_iter_first(&vdomain->mappings, 0, -1UL); |
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while (node) { |
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mapping = container_of(node, struct viommu_mapping, iova); |
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map = (struct virtio_iommu_req_map) { |
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.head.type = VIRTIO_IOMMU_T_MAP, |
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.domain = cpu_to_le32(vdomain->id), |
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.virt_start = cpu_to_le64(mapping->iova.start), |
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.virt_end = cpu_to_le64(mapping->iova.last), |
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.phys_start = cpu_to_le64(mapping->paddr), |
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.flags = cpu_to_le32(mapping->flags), |
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}; |
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|
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ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map)); |
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if (ret) |
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break; |
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|
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node = interval_tree_iter_next(node, 0, -1UL); |
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} |
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spin_unlock_irqrestore(&vdomain->mappings_lock, flags); |
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return ret; |
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} |
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|
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static int viommu_add_resv_mem(struct viommu_endpoint *vdev, |
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struct virtio_iommu_probe_resv_mem *mem, |
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size_t len) |
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{ |
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size_t size; |
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u64 start64, end64; |
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phys_addr_t start, end; |
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struct iommu_resv_region *region = NULL; |
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unsigned long prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; |
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start = start64 = le64_to_cpu(mem->start); |
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end = end64 = le64_to_cpu(mem->end); |
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size = end64 - start64 + 1; |
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|
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/* Catch any overflow, including the unlikely end64 - start64 + 1 = 0 */ |
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if (start != start64 || end != end64 || size < end64 - start64) |
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return -EOVERFLOW; |
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|
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if (len < sizeof(*mem)) |
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return -EINVAL; |
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|
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switch (mem->subtype) { |
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default: |
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dev_warn(vdev->dev, "unknown resv mem subtype 0x%x\n", |
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mem->subtype); |
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fallthrough; |
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case VIRTIO_IOMMU_RESV_MEM_T_RESERVED: |
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region = iommu_alloc_resv_region(start, size, 0, |
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IOMMU_RESV_RESERVED); |
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break; |
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case VIRTIO_IOMMU_RESV_MEM_T_MSI: |
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region = iommu_alloc_resv_region(start, size, prot, |
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IOMMU_RESV_MSI); |
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break; |
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} |
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if (!region) |
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return -ENOMEM; |
|
|
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list_add(®ion->list, &vdev->resv_regions); |
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return 0; |
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} |
|
|
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static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev) |
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{ |
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int ret; |
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u16 type, len; |
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size_t cur = 0; |
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size_t probe_len; |
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struct virtio_iommu_req_probe *probe; |
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struct virtio_iommu_probe_property *prop; |
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struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); |
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struct viommu_endpoint *vdev = dev_iommu_priv_get(dev); |
|
|
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if (!fwspec->num_ids) |
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return -EINVAL; |
|
|
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probe_len = sizeof(*probe) + viommu->probe_size + |
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sizeof(struct virtio_iommu_req_tail); |
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probe = kzalloc(probe_len, GFP_KERNEL); |
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if (!probe) |
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return -ENOMEM; |
|
|
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probe->head.type = VIRTIO_IOMMU_T_PROBE; |
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/* |
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* For now, assume that properties of an endpoint that outputs multiple |
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* IDs are consistent. Only probe the first one. |
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*/ |
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probe->endpoint = cpu_to_le32(fwspec->ids[0]); |
|
|
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ret = viommu_send_req_sync(viommu, probe, probe_len); |
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if (ret) |
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goto out_free; |
|
|
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prop = (void *)probe->properties; |
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type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK; |
|
|
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while (type != VIRTIO_IOMMU_PROBE_T_NONE && |
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cur < viommu->probe_size) { |
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len = le16_to_cpu(prop->length) + sizeof(*prop); |
|
|
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switch (type) { |
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case VIRTIO_IOMMU_PROBE_T_RESV_MEM: |
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ret = viommu_add_resv_mem(vdev, (void *)prop, len); |
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break; |
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default: |
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dev_err(dev, "unknown viommu prop 0x%x\n", type); |
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} |
|
|
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if (ret) |
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dev_err(dev, "failed to parse viommu prop 0x%x\n", type); |
|
|
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cur += len; |
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if (cur >= viommu->probe_size) |
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break; |
|
|
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prop = (void *)probe->properties + cur; |
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type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK; |
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} |
|
|
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out_free: |
|
kfree(probe); |
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return ret; |
|
} |
|
|
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static int viommu_fault_handler(struct viommu_dev *viommu, |
|
struct virtio_iommu_fault *fault) |
|
{ |
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char *reason_str; |
|
|
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u8 reason = fault->reason; |
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u32 flags = le32_to_cpu(fault->flags); |
|
u32 endpoint = le32_to_cpu(fault->endpoint); |
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u64 address = le64_to_cpu(fault->address); |
|
|
|
switch (reason) { |
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case VIRTIO_IOMMU_FAULT_R_DOMAIN: |
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reason_str = "domain"; |
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break; |
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case VIRTIO_IOMMU_FAULT_R_MAPPING: |
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reason_str = "page"; |
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break; |
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case VIRTIO_IOMMU_FAULT_R_UNKNOWN: |
|
default: |
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reason_str = "unknown"; |
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break; |
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} |
|
|
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/* TODO: find EP by ID and report_iommu_fault */ |
|
if (flags & VIRTIO_IOMMU_FAULT_F_ADDRESS) |
|
dev_err_ratelimited(viommu->dev, "%s fault from EP %u at %#llx [%s%s%s]\n", |
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reason_str, endpoint, address, |
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flags & VIRTIO_IOMMU_FAULT_F_READ ? "R" : "", |
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flags & VIRTIO_IOMMU_FAULT_F_WRITE ? "W" : "", |
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flags & VIRTIO_IOMMU_FAULT_F_EXEC ? "X" : ""); |
|
else |
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dev_err_ratelimited(viommu->dev, "%s fault from EP %u\n", |
|
reason_str, endpoint); |
|
return 0; |
|
} |
|
|
|
static void viommu_event_handler(struct virtqueue *vq) |
|
{ |
|
int ret; |
|
unsigned int len; |
|
struct scatterlist sg[1]; |
|
struct viommu_event *evt; |
|
struct viommu_dev *viommu = vq->vdev->priv; |
|
|
|
while ((evt = virtqueue_get_buf(vq, &len)) != NULL) { |
|
if (len > sizeof(*evt)) { |
|
dev_err(viommu->dev, |
|
"invalid event buffer (len %u != %zu)\n", |
|
len, sizeof(*evt)); |
|
} else if (!(evt->head & VIOMMU_FAULT_RESV_MASK)) { |
|
viommu_fault_handler(viommu, &evt->fault); |
|
} |
|
|
|
sg_init_one(sg, evt, sizeof(*evt)); |
|
ret = virtqueue_add_inbuf(vq, sg, 1, evt, GFP_ATOMIC); |
|
if (ret) |
|
dev_err(viommu->dev, "could not add event buffer\n"); |
|
} |
|
|
|
virtqueue_kick(vq); |
|
} |
|
|
|
/* IOMMU API */ |
|
|
|
static struct iommu_domain *viommu_domain_alloc(unsigned type) |
|
{ |
|
struct viommu_domain *vdomain; |
|
|
|
if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) |
|
return NULL; |
|
|
|
vdomain = kzalloc(sizeof(*vdomain), GFP_KERNEL); |
|
if (!vdomain) |
|
return NULL; |
|
|
|
mutex_init(&vdomain->mutex); |
|
spin_lock_init(&vdomain->mappings_lock); |
|
vdomain->mappings = RB_ROOT_CACHED; |
|
|
|
if (type == IOMMU_DOMAIN_DMA && |
|
iommu_get_dma_cookie(&vdomain->domain)) { |
|
kfree(vdomain); |
|
return NULL; |
|
} |
|
|
|
return &vdomain->domain; |
|
} |
|
|
|
static int viommu_domain_finalise(struct viommu_endpoint *vdev, |
|
struct iommu_domain *domain) |
|
{ |
|
int ret; |
|
unsigned long viommu_page_size; |
|
struct viommu_dev *viommu = vdev->viommu; |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
viommu_page_size = 1UL << __ffs(viommu->pgsize_bitmap); |
|
if (viommu_page_size > PAGE_SIZE) { |
|
dev_err(vdev->dev, |
|
"granule 0x%lx larger than system page size 0x%lx\n", |
|
viommu_page_size, PAGE_SIZE); |
|
return -EINVAL; |
|
} |
|
|
|
ret = ida_alloc_range(&viommu->domain_ids, viommu->first_domain, |
|
viommu->last_domain, GFP_KERNEL); |
|
if (ret < 0) |
|
return ret; |
|
|
|
vdomain->id = (unsigned int)ret; |
|
|
|
domain->pgsize_bitmap = viommu->pgsize_bitmap; |
|
domain->geometry = viommu->geometry; |
|
|
|
vdomain->map_flags = viommu->map_flags; |
|
vdomain->viommu = viommu; |
|
|
|
return 0; |
|
} |
|
|
|
static void viommu_domain_free(struct iommu_domain *domain) |
|
{ |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
iommu_put_dma_cookie(domain); |
|
|
|
/* Free all remaining mappings (size 2^64) */ |
|
viommu_del_mappings(vdomain, 0, 0); |
|
|
|
if (vdomain->viommu) |
|
ida_free(&vdomain->viommu->domain_ids, vdomain->id); |
|
|
|
kfree(vdomain); |
|
} |
|
|
|
static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev) |
|
{ |
|
int i; |
|
int ret = 0; |
|
struct virtio_iommu_req_attach req; |
|
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); |
|
struct viommu_endpoint *vdev = dev_iommu_priv_get(dev); |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
mutex_lock(&vdomain->mutex); |
|
if (!vdomain->viommu) { |
|
/* |
|
* Properly initialize the domain now that we know which viommu |
|
* owns it. |
|
*/ |
|
ret = viommu_domain_finalise(vdev, domain); |
|
} else if (vdomain->viommu != vdev->viommu) { |
|
dev_err(dev, "cannot attach to foreign vIOMMU\n"); |
|
ret = -EXDEV; |
|
} |
|
mutex_unlock(&vdomain->mutex); |
|
|
|
if (ret) |
|
return ret; |
|
|
|
/* |
|
* In the virtio-iommu device, when attaching the endpoint to a new |
|
* domain, it is detached from the old one and, if as as a result the |
|
* old domain isn't attached to any endpoint, all mappings are removed |
|
* from the old domain and it is freed. |
|
* |
|
* In the driver the old domain still exists, and its mappings will be |
|
* recreated if it gets reattached to an endpoint. Otherwise it will be |
|
* freed explicitly. |
|
* |
|
* vdev->vdomain is protected by group->mutex |
|
*/ |
|
if (vdev->vdomain) |
|
vdev->vdomain->nr_endpoints--; |
|
|
|
req = (struct virtio_iommu_req_attach) { |
|
.head.type = VIRTIO_IOMMU_T_ATTACH, |
|
.domain = cpu_to_le32(vdomain->id), |
|
}; |
|
|
|
for (i = 0; i < fwspec->num_ids; i++) { |
|
req.endpoint = cpu_to_le32(fwspec->ids[i]); |
|
|
|
ret = viommu_send_req_sync(vdomain->viommu, &req, sizeof(req)); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
if (!vdomain->nr_endpoints) { |
|
/* |
|
* This endpoint is the first to be attached to the domain. |
|
* Replay existing mappings (e.g. SW MSI). |
|
*/ |
|
ret = viommu_replay_mappings(vdomain); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
vdomain->nr_endpoints++; |
|
vdev->vdomain = vdomain; |
|
|
|
return 0; |
|
} |
|
|
|
static int viommu_map(struct iommu_domain *domain, unsigned long iova, |
|
phys_addr_t paddr, size_t size, int prot, gfp_t gfp) |
|
{ |
|
int ret; |
|
u32 flags; |
|
struct virtio_iommu_req_map map; |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
flags = (prot & IOMMU_READ ? VIRTIO_IOMMU_MAP_F_READ : 0) | |
|
(prot & IOMMU_WRITE ? VIRTIO_IOMMU_MAP_F_WRITE : 0) | |
|
(prot & IOMMU_MMIO ? VIRTIO_IOMMU_MAP_F_MMIO : 0); |
|
|
|
if (flags & ~vdomain->map_flags) |
|
return -EINVAL; |
|
|
|
ret = viommu_add_mapping(vdomain, iova, paddr, size, flags); |
|
if (ret) |
|
return ret; |
|
|
|
map = (struct virtio_iommu_req_map) { |
|
.head.type = VIRTIO_IOMMU_T_MAP, |
|
.domain = cpu_to_le32(vdomain->id), |
|
.virt_start = cpu_to_le64(iova), |
|
.phys_start = cpu_to_le64(paddr), |
|
.virt_end = cpu_to_le64(iova + size - 1), |
|
.flags = cpu_to_le32(flags), |
|
}; |
|
|
|
if (!vdomain->nr_endpoints) |
|
return 0; |
|
|
|
ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map)); |
|
if (ret) |
|
viommu_del_mappings(vdomain, iova, size); |
|
|
|
return ret; |
|
} |
|
|
|
static size_t viommu_unmap(struct iommu_domain *domain, unsigned long iova, |
|
size_t size, struct iommu_iotlb_gather *gather) |
|
{ |
|
int ret = 0; |
|
size_t unmapped; |
|
struct virtio_iommu_req_unmap unmap; |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
unmapped = viommu_del_mappings(vdomain, iova, size); |
|
if (unmapped < size) |
|
return 0; |
|
|
|
/* Device already removed all mappings after detach. */ |
|
if (!vdomain->nr_endpoints) |
|
return unmapped; |
|
|
|
unmap = (struct virtio_iommu_req_unmap) { |
|
.head.type = VIRTIO_IOMMU_T_UNMAP, |
|
.domain = cpu_to_le32(vdomain->id), |
|
.virt_start = cpu_to_le64(iova), |
|
.virt_end = cpu_to_le64(iova + unmapped - 1), |
|
}; |
|
|
|
ret = viommu_add_req(vdomain->viommu, &unmap, sizeof(unmap)); |
|
return ret ? 0 : unmapped; |
|
} |
|
|
|
static phys_addr_t viommu_iova_to_phys(struct iommu_domain *domain, |
|
dma_addr_t iova) |
|
{ |
|
u64 paddr = 0; |
|
unsigned long flags; |
|
struct viommu_mapping *mapping; |
|
struct interval_tree_node *node; |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
spin_lock_irqsave(&vdomain->mappings_lock, flags); |
|
node = interval_tree_iter_first(&vdomain->mappings, iova, iova); |
|
if (node) { |
|
mapping = container_of(node, struct viommu_mapping, iova); |
|
paddr = mapping->paddr + (iova - mapping->iova.start); |
|
} |
|
spin_unlock_irqrestore(&vdomain->mappings_lock, flags); |
|
|
|
return paddr; |
|
} |
|
|
|
static void viommu_iotlb_sync(struct iommu_domain *domain, |
|
struct iommu_iotlb_gather *gather) |
|
{ |
|
struct viommu_domain *vdomain = to_viommu_domain(domain); |
|
|
|
viommu_sync_req(vdomain->viommu); |
|
} |
|
|
|
static void viommu_get_resv_regions(struct device *dev, struct list_head *head) |
|
{ |
|
struct iommu_resv_region *entry, *new_entry, *msi = NULL; |
|
struct viommu_endpoint *vdev = dev_iommu_priv_get(dev); |
|
int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; |
|
|
|
list_for_each_entry(entry, &vdev->resv_regions, list) { |
|
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); |
|
} |
|
|
|
/* |
|
* If the device didn't register any bypass MSI window, add a |
|
* software-mapped region. |
|
*/ |
|
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 struct iommu_ops viommu_ops; |
|
static struct virtio_driver virtio_iommu_drv; |
|
|
|
static int viommu_match_node(struct device *dev, const void *data) |
|
{ |
|
return dev->parent->fwnode == data; |
|
} |
|
|
|
static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode) |
|
{ |
|
struct device *dev = driver_find_device(&virtio_iommu_drv.driver, NULL, |
|
fwnode, viommu_match_node); |
|
put_device(dev); |
|
|
|
return dev ? dev_to_virtio(dev)->priv : NULL; |
|
} |
|
|
|
static struct iommu_device *viommu_probe_device(struct device *dev) |
|
{ |
|
int ret; |
|
struct viommu_endpoint *vdev; |
|
struct viommu_dev *viommu = NULL; |
|
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); |
|
|
|
if (!fwspec || fwspec->ops != &viommu_ops) |
|
return ERR_PTR(-ENODEV); |
|
|
|
viommu = viommu_get_by_fwnode(fwspec->iommu_fwnode); |
|
if (!viommu) |
|
return ERR_PTR(-ENODEV); |
|
|
|
vdev = kzalloc(sizeof(*vdev), GFP_KERNEL); |
|
if (!vdev) |
|
return ERR_PTR(-ENOMEM); |
|
|
|
vdev->dev = dev; |
|
vdev->viommu = viommu; |
|
INIT_LIST_HEAD(&vdev->resv_regions); |
|
dev_iommu_priv_set(dev, vdev); |
|
|
|
if (viommu->probe_size) { |
|
/* Get additional information for this endpoint */ |
|
ret = viommu_probe_endpoint(viommu, dev); |
|
if (ret) |
|
goto err_free_dev; |
|
} |
|
|
|
return &viommu->iommu; |
|
|
|
err_free_dev: |
|
generic_iommu_put_resv_regions(dev, &vdev->resv_regions); |
|
kfree(vdev); |
|
|
|
return ERR_PTR(ret); |
|
} |
|
|
|
static void viommu_release_device(struct device *dev) |
|
{ |
|
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); |
|
struct viommu_endpoint *vdev; |
|
|
|
if (!fwspec || fwspec->ops != &viommu_ops) |
|
return; |
|
|
|
vdev = dev_iommu_priv_get(dev); |
|
|
|
generic_iommu_put_resv_regions(dev, &vdev->resv_regions); |
|
kfree(vdev); |
|
} |
|
|
|
static struct iommu_group *viommu_device_group(struct device *dev) |
|
{ |
|
if (dev_is_pci(dev)) |
|
return pci_device_group(dev); |
|
else |
|
return generic_device_group(dev); |
|
} |
|
|
|
static int viommu_of_xlate(struct device *dev, struct of_phandle_args *args) |
|
{ |
|
return iommu_fwspec_add_ids(dev, args->args, 1); |
|
} |
|
|
|
static struct iommu_ops viommu_ops = { |
|
.domain_alloc = viommu_domain_alloc, |
|
.domain_free = viommu_domain_free, |
|
.attach_dev = viommu_attach_dev, |
|
.map = viommu_map, |
|
.unmap = viommu_unmap, |
|
.iova_to_phys = viommu_iova_to_phys, |
|
.iotlb_sync = viommu_iotlb_sync, |
|
.probe_device = viommu_probe_device, |
|
.release_device = viommu_release_device, |
|
.device_group = viommu_device_group, |
|
.get_resv_regions = viommu_get_resv_regions, |
|
.put_resv_regions = generic_iommu_put_resv_regions, |
|
.of_xlate = viommu_of_xlate, |
|
}; |
|
|
|
static int viommu_init_vqs(struct viommu_dev *viommu) |
|
{ |
|
struct virtio_device *vdev = dev_to_virtio(viommu->dev); |
|
const char *names[] = { "request", "event" }; |
|
vq_callback_t *callbacks[] = { |
|
NULL, /* No async requests */ |
|
viommu_event_handler, |
|
}; |
|
|
|
return virtio_find_vqs(vdev, VIOMMU_NR_VQS, viommu->vqs, callbacks, |
|
names, NULL); |
|
} |
|
|
|
static int viommu_fill_evtq(struct viommu_dev *viommu) |
|
{ |
|
int i, ret; |
|
struct scatterlist sg[1]; |
|
struct viommu_event *evts; |
|
struct virtqueue *vq = viommu->vqs[VIOMMU_EVENT_VQ]; |
|
size_t nr_evts = vq->num_free; |
|
|
|
viommu->evts = evts = devm_kmalloc_array(viommu->dev, nr_evts, |
|
sizeof(*evts), GFP_KERNEL); |
|
if (!evts) |
|
return -ENOMEM; |
|
|
|
for (i = 0; i < nr_evts; i++) { |
|
sg_init_one(sg, &evts[i], sizeof(*evts)); |
|
ret = virtqueue_add_inbuf(vq, sg, 1, &evts[i], GFP_KERNEL); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int viommu_probe(struct virtio_device *vdev) |
|
{ |
|
struct device *parent_dev = vdev->dev.parent; |
|
struct viommu_dev *viommu = NULL; |
|
struct device *dev = &vdev->dev; |
|
u64 input_start = 0; |
|
u64 input_end = -1UL; |
|
int ret; |
|
|
|
if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || |
|
!virtio_has_feature(vdev, VIRTIO_IOMMU_F_MAP_UNMAP)) |
|
return -ENODEV; |
|
|
|
viommu = devm_kzalloc(dev, sizeof(*viommu), GFP_KERNEL); |
|
if (!viommu) |
|
return -ENOMEM; |
|
|
|
spin_lock_init(&viommu->request_lock); |
|
ida_init(&viommu->domain_ids); |
|
viommu->dev = dev; |
|
viommu->vdev = vdev; |
|
INIT_LIST_HEAD(&viommu->requests); |
|
|
|
ret = viommu_init_vqs(viommu); |
|
if (ret) |
|
return ret; |
|
|
|
virtio_cread_le(vdev, struct virtio_iommu_config, page_size_mask, |
|
&viommu->pgsize_bitmap); |
|
|
|
if (!viommu->pgsize_bitmap) { |
|
ret = -EINVAL; |
|
goto err_free_vqs; |
|
} |
|
|
|
viommu->map_flags = VIRTIO_IOMMU_MAP_F_READ | VIRTIO_IOMMU_MAP_F_WRITE; |
|
viommu->last_domain = ~0U; |
|
|
|
/* Optional features */ |
|
virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE, |
|
struct virtio_iommu_config, input_range.start, |
|
&input_start); |
|
|
|
virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE, |
|
struct virtio_iommu_config, input_range.end, |
|
&input_end); |
|
|
|
virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_RANGE, |
|
struct virtio_iommu_config, domain_range.start, |
|
&viommu->first_domain); |
|
|
|
virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_RANGE, |
|
struct virtio_iommu_config, domain_range.end, |
|
&viommu->last_domain); |
|
|
|
virtio_cread_le_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, |
|
.force_aperture = true, |
|
}; |
|
|
|
if (virtio_has_feature(vdev, VIRTIO_IOMMU_F_MMIO)) |
|
viommu->map_flags |= VIRTIO_IOMMU_MAP_F_MMIO; |
|
|
|
viommu_ops.pgsize_bitmap = viommu->pgsize_bitmap; |
|
|
|
virtio_device_ready(vdev); |
|
|
|
/* Populate the event queue with buffers */ |
|
ret = viommu_fill_evtq(viommu); |
|
if (ret) |
|
goto err_free_vqs; |
|
|
|
ret = iommu_device_sysfs_add(&viommu->iommu, dev, NULL, "%s", |
|
virtio_bus_name(vdev)); |
|
if (ret) |
|
goto err_free_vqs; |
|
|
|
iommu_device_set_ops(&viommu->iommu, &viommu_ops); |
|
iommu_device_set_fwnode(&viommu->iommu, parent_dev->fwnode); |
|
|
|
iommu_device_register(&viommu->iommu); |
|
|
|
#ifdef CONFIG_PCI |
|
if (pci_bus_type.iommu_ops != &viommu_ops) { |
|
ret = bus_set_iommu(&pci_bus_type, &viommu_ops); |
|
if (ret) |
|
goto err_unregister; |
|
} |
|
#endif |
|
#ifdef CONFIG_ARM_AMBA |
|
if (amba_bustype.iommu_ops != &viommu_ops) { |
|
ret = bus_set_iommu(&amba_bustype, &viommu_ops); |
|
if (ret) |
|
goto err_unregister; |
|
} |
|
#endif |
|
if (platform_bus_type.iommu_ops != &viommu_ops) { |
|
ret = bus_set_iommu(&platform_bus_type, &viommu_ops); |
|
if (ret) |
|
goto err_unregister; |
|
} |
|
|
|
vdev->priv = viommu; |
|
|
|
dev_info(dev, "input address: %u bits\n", |
|
order_base_2(viommu->geometry.aperture_end)); |
|
dev_info(dev, "page mask: %#llx\n", viommu->pgsize_bitmap); |
|
|
|
return 0; |
|
|
|
err_unregister: |
|
iommu_device_sysfs_remove(&viommu->iommu); |
|
iommu_device_unregister(&viommu->iommu); |
|
err_free_vqs: |
|
vdev->config->del_vqs(vdev); |
|
|
|
return ret; |
|
} |
|
|
|
static void viommu_remove(struct virtio_device *vdev) |
|
{ |
|
struct viommu_dev *viommu = vdev->priv; |
|
|
|
iommu_device_sysfs_remove(&viommu->iommu); |
|
iommu_device_unregister(&viommu->iommu); |
|
|
|
/* Stop all virtqueues */ |
|
vdev->config->reset(vdev); |
|
vdev->config->del_vqs(vdev); |
|
|
|
dev_info(&vdev->dev, "device removed\n"); |
|
} |
|
|
|
static void viommu_config_changed(struct virtio_device *vdev) |
|
{ |
|
dev_warn(&vdev->dev, "config changed\n"); |
|
} |
|
|
|
static unsigned int features[] = { |
|
VIRTIO_IOMMU_F_MAP_UNMAP, |
|
VIRTIO_IOMMU_F_INPUT_RANGE, |
|
VIRTIO_IOMMU_F_DOMAIN_RANGE, |
|
VIRTIO_IOMMU_F_PROBE, |
|
VIRTIO_IOMMU_F_MMIO, |
|
}; |
|
|
|
static struct virtio_device_id id_table[] = { |
|
{ VIRTIO_ID_IOMMU, VIRTIO_DEV_ANY_ID }, |
|
{ 0 }, |
|
}; |
|
MODULE_DEVICE_TABLE(virtio, id_table); |
|
|
|
static struct virtio_driver virtio_iommu_drv = { |
|
.driver.name = KBUILD_MODNAME, |
|
.driver.owner = THIS_MODULE, |
|
.id_table = id_table, |
|
.feature_table = features, |
|
.feature_table_size = ARRAY_SIZE(features), |
|
.probe = viommu_probe, |
|
.remove = viommu_remove, |
|
.config_changed = viommu_config_changed, |
|
}; |
|
|
|
module_virtio_driver(virtio_iommu_drv); |
|
|
|
MODULE_DESCRIPTION("Virtio IOMMU driver"); |
|
MODULE_AUTHOR("Jean-Philippe Brucker <[email protected]>"); |
|
MODULE_LICENSE("GPL v2");
|
|
|