1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright(c) 2019 Intel Corporation. All rights rsvd. */ 3 #include <linux/init.h> 4 #include <linux/kernel.h> 5 #include <linux/module.h> 6 #include <linux/pci.h> 7 #include <linux/device.h> 8 #include <linux/sched/task.h> 9 #include <linux/intel-svm.h> 10 #include <linux/io-64-nonatomic-lo-hi.h> 11 #include <linux/cdev.h> 12 #include <linux/fs.h> 13 #include <linux/poll.h> 14 #include <linux/iommu.h> 15 #include <uapi/linux/idxd.h> 16 #include "registers.h" 17 #include "idxd.h" 18 19 struct idxd_cdev_context { 20 const char *name; 21 dev_t devt; 22 struct ida minor_ida; 23 }; 24 25 /* 26 * ictx is an array based off of accelerator types. enum idxd_type 27 * is used as index 28 */ 29 static struct idxd_cdev_context ictx[IDXD_TYPE_MAX] = { 30 { .name = "dsa" }, 31 { .name = "iax" } 32 }; 33 34 struct idxd_user_context { 35 struct idxd_wq *wq; 36 struct task_struct *task; 37 unsigned int pasid; 38 unsigned int flags; 39 struct iommu_sva *sva; 40 }; 41 42 static void idxd_cdev_dev_release(struct device *dev) 43 { 44 struct idxd_cdev *idxd_cdev = container_of(dev, struct idxd_cdev, dev); 45 struct idxd_cdev_context *cdev_ctx; 46 struct idxd_wq *wq = idxd_cdev->wq; 47 48 cdev_ctx = &ictx[wq->idxd->data->type]; 49 ida_simple_remove(&cdev_ctx->minor_ida, idxd_cdev->minor); 50 kfree(idxd_cdev); 51 } 52 53 static struct device_type idxd_cdev_device_type = { 54 .name = "idxd_cdev", 55 .release = idxd_cdev_dev_release, 56 }; 57 58 static inline struct idxd_cdev *inode_idxd_cdev(struct inode *inode) 59 { 60 struct cdev *cdev = inode->i_cdev; 61 62 return container_of(cdev, struct idxd_cdev, cdev); 63 } 64 65 static inline struct idxd_wq *inode_wq(struct inode *inode) 66 { 67 struct idxd_cdev *idxd_cdev = inode_idxd_cdev(inode); 68 69 return idxd_cdev->wq; 70 } 71 72 static int idxd_cdev_open(struct inode *inode, struct file *filp) 73 { 74 struct idxd_user_context *ctx; 75 struct idxd_device *idxd; 76 struct idxd_wq *wq; 77 struct device *dev; 78 int rc = 0; 79 struct iommu_sva *sva; 80 unsigned int pasid; 81 82 wq = inode_wq(inode); 83 idxd = wq->idxd; 84 dev = &idxd->pdev->dev; 85 86 dev_dbg(dev, "%s called: %d\n", __func__, idxd_wq_refcount(wq)); 87 88 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); 89 if (!ctx) 90 return -ENOMEM; 91 92 mutex_lock(&wq->wq_lock); 93 94 if (idxd_wq_refcount(wq) > 0 && wq_dedicated(wq)) { 95 rc = -EBUSY; 96 goto failed; 97 } 98 99 ctx->wq = wq; 100 filp->private_data = ctx; 101 102 if (device_pasid_enabled(idxd)) { 103 sva = iommu_sva_bind_device(dev, current->mm, NULL); 104 if (IS_ERR(sva)) { 105 rc = PTR_ERR(sva); 106 dev_err(dev, "pasid allocation failed: %d\n", rc); 107 goto failed; 108 } 109 110 pasid = iommu_sva_get_pasid(sva); 111 if (pasid == IOMMU_PASID_INVALID) { 112 iommu_sva_unbind_device(sva); 113 goto failed; 114 } 115 116 ctx->sva = sva; 117 ctx->pasid = pasid; 118 119 if (wq_dedicated(wq)) { 120 rc = idxd_wq_set_pasid(wq, pasid); 121 if (rc < 0) { 122 iommu_sva_unbind_device(sva); 123 dev_err(dev, "wq set pasid failed: %d\n", rc); 124 goto failed; 125 } 126 } 127 } 128 129 idxd_wq_get(wq); 130 mutex_unlock(&wq->wq_lock); 131 return 0; 132 133 failed: 134 mutex_unlock(&wq->wq_lock); 135 kfree(ctx); 136 return rc; 137 } 138 139 static int idxd_cdev_release(struct inode *node, struct file *filep) 140 { 141 struct idxd_user_context *ctx = filep->private_data; 142 struct idxd_wq *wq = ctx->wq; 143 struct idxd_device *idxd = wq->idxd; 144 struct device *dev = &idxd->pdev->dev; 145 int rc; 146 147 dev_dbg(dev, "%s called\n", __func__); 148 filep->private_data = NULL; 149 150 /* Wait for in-flight operations to complete. */ 151 if (wq_shared(wq)) { 152 idxd_device_drain_pasid(idxd, ctx->pasid); 153 } else { 154 if (device_pasid_enabled(idxd)) { 155 /* The wq disable in the disable pasid function will drain the wq */ 156 rc = idxd_wq_disable_pasid(wq); 157 if (rc < 0) 158 dev_err(dev, "wq disable pasid failed.\n"); 159 } else { 160 idxd_wq_drain(wq); 161 } 162 } 163 164 if (ctx->sva) 165 iommu_sva_unbind_device(ctx->sva); 166 kfree(ctx); 167 mutex_lock(&wq->wq_lock); 168 idxd_wq_put(wq); 169 mutex_unlock(&wq->wq_lock); 170 return 0; 171 } 172 173 static int check_vma(struct idxd_wq *wq, struct vm_area_struct *vma, 174 const char *func) 175 { 176 struct device *dev = &wq->idxd->pdev->dev; 177 178 if ((vma->vm_end - vma->vm_start) > PAGE_SIZE) { 179 dev_info_ratelimited(dev, 180 "%s: %s: mapping too large: %lu\n", 181 current->comm, func, 182 vma->vm_end - vma->vm_start); 183 return -EINVAL; 184 } 185 186 return 0; 187 } 188 189 static int idxd_cdev_mmap(struct file *filp, struct vm_area_struct *vma) 190 { 191 struct idxd_user_context *ctx = filp->private_data; 192 struct idxd_wq *wq = ctx->wq; 193 struct idxd_device *idxd = wq->idxd; 194 struct pci_dev *pdev = idxd->pdev; 195 phys_addr_t base = pci_resource_start(pdev, IDXD_WQ_BAR); 196 unsigned long pfn; 197 int rc; 198 199 dev_dbg(&pdev->dev, "%s called\n", __func__); 200 rc = check_vma(wq, vma, __func__); 201 if (rc < 0) 202 return rc; 203 204 vma->vm_flags |= VM_DONTCOPY; 205 pfn = (base + idxd_get_wq_portal_full_offset(wq->id, 206 IDXD_PORTAL_LIMITED)) >> PAGE_SHIFT; 207 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 208 vma->vm_private_data = ctx; 209 210 return io_remap_pfn_range(vma, vma->vm_start, pfn, PAGE_SIZE, 211 vma->vm_page_prot); 212 } 213 214 static __poll_t idxd_cdev_poll(struct file *filp, 215 struct poll_table_struct *wait) 216 { 217 struct idxd_user_context *ctx = filp->private_data; 218 struct idxd_wq *wq = ctx->wq; 219 struct idxd_device *idxd = wq->idxd; 220 unsigned long flags; 221 __poll_t out = 0; 222 223 poll_wait(filp, &wq->err_queue, wait); 224 spin_lock_irqsave(&idxd->dev_lock, flags); 225 if (idxd->sw_err.valid) 226 out = EPOLLIN | EPOLLRDNORM; 227 spin_unlock_irqrestore(&idxd->dev_lock, flags); 228 229 return out; 230 } 231 232 static const struct file_operations idxd_cdev_fops = { 233 .owner = THIS_MODULE, 234 .open = idxd_cdev_open, 235 .release = idxd_cdev_release, 236 .mmap = idxd_cdev_mmap, 237 .poll = idxd_cdev_poll, 238 }; 239 240 int idxd_cdev_get_major(struct idxd_device *idxd) 241 { 242 return MAJOR(ictx[idxd->data->type].devt); 243 } 244 245 int idxd_wq_add_cdev(struct idxd_wq *wq) 246 { 247 struct idxd_device *idxd = wq->idxd; 248 struct idxd_cdev *idxd_cdev; 249 struct cdev *cdev; 250 struct device *dev; 251 struct idxd_cdev_context *cdev_ctx; 252 int rc, minor; 253 254 idxd_cdev = kzalloc(sizeof(*idxd_cdev), GFP_KERNEL); 255 if (!idxd_cdev) 256 return -ENOMEM; 257 258 idxd_cdev->wq = wq; 259 cdev = &idxd_cdev->cdev; 260 dev = &idxd_cdev->dev; 261 cdev_ctx = &ictx[wq->idxd->data->type]; 262 minor = ida_simple_get(&cdev_ctx->minor_ida, 0, MINORMASK, GFP_KERNEL); 263 if (minor < 0) { 264 kfree(idxd_cdev); 265 return minor; 266 } 267 idxd_cdev->minor = minor; 268 269 device_initialize(dev); 270 dev->parent = &wq->conf_dev; 271 dev->bus = &dsa_bus_type; 272 dev->type = &idxd_cdev_device_type; 273 dev->devt = MKDEV(MAJOR(cdev_ctx->devt), minor); 274 275 rc = dev_set_name(dev, "%s/wq%u.%u", idxd->data->name_prefix, idxd->id, wq->id); 276 if (rc < 0) 277 goto err; 278 279 wq->idxd_cdev = idxd_cdev; 280 cdev_init(cdev, &idxd_cdev_fops); 281 rc = cdev_device_add(cdev, dev); 282 if (rc) { 283 dev_dbg(&wq->idxd->pdev->dev, "cdev_add failed: %d\n", rc); 284 goto err; 285 } 286 287 return 0; 288 289 err: 290 put_device(dev); 291 wq->idxd_cdev = NULL; 292 return rc; 293 } 294 295 void idxd_wq_del_cdev(struct idxd_wq *wq) 296 { 297 struct idxd_cdev *idxd_cdev; 298 struct idxd_cdev_context *cdev_ctx; 299 300 cdev_ctx = &ictx[wq->idxd->data->type]; 301 idxd_cdev = wq->idxd_cdev; 302 wq->idxd_cdev = NULL; 303 cdev_device_del(&idxd_cdev->cdev, &idxd_cdev->dev); 304 put_device(&idxd_cdev->dev); 305 } 306 307 int idxd_cdev_register(void) 308 { 309 int rc, i; 310 311 for (i = 0; i < IDXD_TYPE_MAX; i++) { 312 ida_init(&ictx[i].minor_ida); 313 rc = alloc_chrdev_region(&ictx[i].devt, 0, MINORMASK, 314 ictx[i].name); 315 if (rc) 316 return rc; 317 } 318 319 return 0; 320 } 321 322 void idxd_cdev_remove(void) 323 { 324 int i; 325 326 for (i = 0; i < IDXD_TYPE_MAX; i++) { 327 unregister_chrdev_region(ictx[i].devt, MINORMASK); 328 ida_destroy(&ictx[i].minor_ida); 329 } 330 } 331