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