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path: root/drivers/dma/idxd/cdev.c
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Diffstat (limited to 'drivers/dma/idxd/cdev.c')
-rw-r--r--drivers/dma/idxd/cdev.c302
1 files changed, 302 insertions, 0 deletions
diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c
new file mode 100644
index 000000000000..1d7347825b95
--- /dev/null
+++ b/drivers/dma/idxd/cdev.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2019 Intel Corporation. All rights rsvd. */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/device.h>
+#include <linux/sched/task.h>
+#include <linux/intel-svm.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <uapi/linux/idxd.h>
+#include "registers.h"
+#include "idxd.h"
+
+struct idxd_cdev_context {
+ const char *name;
+ dev_t devt;
+ struct ida minor_ida;
+};
+
+/*
+ * ictx is an array based off of accelerator types. enum idxd_type
+ * is used as index
+ */
+static struct idxd_cdev_context ictx[IDXD_TYPE_MAX] = {
+ { .name = "dsa" },
+};
+
+struct idxd_user_context {
+ struct idxd_wq *wq;
+ struct task_struct *task;
+ unsigned int flags;
+};
+
+enum idxd_cdev_cleanup {
+ CDEV_NORMAL = 0,
+ CDEV_FAILED,
+};
+
+static void idxd_cdev_dev_release(struct device *dev)
+{
+ dev_dbg(dev, "releasing cdev device\n");
+ kfree(dev);
+}
+
+static struct device_type idxd_cdev_device_type = {
+ .name = "idxd_cdev",
+ .release = idxd_cdev_dev_release,
+};
+
+static inline struct idxd_cdev *inode_idxd_cdev(struct inode *inode)
+{
+ struct cdev *cdev = inode->i_cdev;
+
+ return container_of(cdev, struct idxd_cdev, cdev);
+}
+
+static inline struct idxd_wq *idxd_cdev_wq(struct idxd_cdev *idxd_cdev)
+{
+ return container_of(idxd_cdev, struct idxd_wq, idxd_cdev);
+}
+
+static inline struct idxd_wq *inode_wq(struct inode *inode)
+{
+ return idxd_cdev_wq(inode_idxd_cdev(inode));
+}
+
+static int idxd_cdev_open(struct inode *inode, struct file *filp)
+{
+ struct idxd_user_context *ctx;
+ struct idxd_device *idxd;
+ struct idxd_wq *wq;
+ struct device *dev;
+ struct idxd_cdev *idxd_cdev;
+
+ wq = inode_wq(inode);
+ idxd = wq->idxd;
+ dev = &idxd->pdev->dev;
+ idxd_cdev = &wq->idxd_cdev;
+
+ dev_dbg(dev, "%s called\n", __func__);
+
+ if (idxd_wq_refcount(wq) > 1 && wq_dedicated(wq))
+ return -EBUSY;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->wq = wq;
+ filp->private_data = ctx;
+ idxd_wq_get(wq);
+ return 0;
+}
+
+static int idxd_cdev_release(struct inode *node, struct file *filep)
+{
+ struct idxd_user_context *ctx = filep->private_data;
+ struct idxd_wq *wq = ctx->wq;
+ struct idxd_device *idxd = wq->idxd;
+ struct device *dev = &idxd->pdev->dev;
+
+ dev_dbg(dev, "%s called\n", __func__);
+ filep->private_data = NULL;
+
+ kfree(ctx);
+ idxd_wq_put(wq);
+ return 0;
+}
+
+static int check_vma(struct idxd_wq *wq, struct vm_area_struct *vma,
+ const char *func)
+{
+ struct device *dev = &wq->idxd->pdev->dev;
+
+ if ((vma->vm_end - vma->vm_start) > PAGE_SIZE) {
+ dev_info_ratelimited(dev,
+ "%s: %s: mapping too large: %lu\n",
+ current->comm, func,
+ vma->vm_end - vma->vm_start);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int idxd_cdev_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ struct idxd_user_context *ctx = filp->private_data;
+ struct idxd_wq *wq = ctx->wq;
+ struct idxd_device *idxd = wq->idxd;
+ struct pci_dev *pdev = idxd->pdev;
+ phys_addr_t base = pci_resource_start(pdev, IDXD_WQ_BAR);
+ unsigned long pfn;
+ int rc;
+
+ dev_dbg(&pdev->dev, "%s called\n", __func__);
+ rc = check_vma(wq, vma, __func__);
+
+ vma->vm_flags |= VM_DONTCOPY;
+ pfn = (base + idxd_get_wq_portal_full_offset(wq->id,
+ IDXD_PORTAL_LIMITED)) >> PAGE_SHIFT;
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ vma->vm_private_data = ctx;
+
+ return io_remap_pfn_range(vma, vma->vm_start, pfn, PAGE_SIZE,
+ vma->vm_page_prot);
+}
+
+static __poll_t idxd_cdev_poll(struct file *filp,
+ struct poll_table_struct *wait)
+{
+ struct idxd_user_context *ctx = filp->private_data;
+ struct idxd_wq *wq = ctx->wq;
+ struct idxd_device *idxd = wq->idxd;
+ struct idxd_cdev *idxd_cdev = &wq->idxd_cdev;
+ unsigned long flags;
+ __poll_t out = 0;
+
+ poll_wait(filp, &idxd_cdev->err_queue, wait);
+ spin_lock_irqsave(&idxd->dev_lock, flags);
+ if (idxd->sw_err.valid)
+ out = EPOLLIN | EPOLLRDNORM;
+ spin_unlock_irqrestore(&idxd->dev_lock, flags);
+
+ return out;
+}
+
+static const struct file_operations idxd_cdev_fops = {
+ .owner = THIS_MODULE,
+ .open = idxd_cdev_open,
+ .release = idxd_cdev_release,
+ .mmap = idxd_cdev_mmap,
+ .poll = idxd_cdev_poll,
+};
+
+int idxd_cdev_get_major(struct idxd_device *idxd)
+{
+ return MAJOR(ictx[idxd->type].devt);
+}
+
+static int idxd_wq_cdev_dev_setup(struct idxd_wq *wq)
+{
+ struct idxd_device *idxd = wq->idxd;
+ struct idxd_cdev *idxd_cdev = &wq->idxd_cdev;
+ struct idxd_cdev_context *cdev_ctx;
+ struct device *dev;
+ int minor, rc;
+
+ idxd_cdev->dev = kzalloc(sizeof(*idxd_cdev->dev), GFP_KERNEL);
+ if (!idxd_cdev->dev)
+ return -ENOMEM;
+
+ dev = idxd_cdev->dev;
+ dev->parent = &idxd->pdev->dev;
+ dev_set_name(dev, "%s/wq%u.%u", idxd_get_dev_name(idxd),
+ idxd->id, wq->id);
+ dev->bus = idxd_get_bus_type(idxd);
+
+ cdev_ctx = &ictx[wq->idxd->type];
+ minor = ida_simple_get(&cdev_ctx->minor_ida, 0, MINORMASK, GFP_KERNEL);
+ if (minor < 0) {
+ rc = minor;
+ goto ida_err;
+ }
+
+ dev->devt = MKDEV(MAJOR(cdev_ctx->devt), minor);
+ dev->type = &idxd_cdev_device_type;
+ rc = device_register(dev);
+ if (rc < 0) {
+ dev_err(&idxd->pdev->dev, "device register failed\n");
+ put_device(dev);
+ goto dev_reg_err;
+ }
+ idxd_cdev->minor = minor;
+
+ return 0;
+
+ dev_reg_err:
+ ida_simple_remove(&cdev_ctx->minor_ida, MINOR(dev->devt));
+ ida_err:
+ kfree(dev);
+ idxd_cdev->dev = NULL;
+ return rc;
+}
+
+static void idxd_wq_cdev_cleanup(struct idxd_wq *wq,
+ enum idxd_cdev_cleanup cdev_state)
+{
+ struct idxd_cdev *idxd_cdev = &wq->idxd_cdev;
+ struct idxd_cdev_context *cdev_ctx;
+
+ cdev_ctx = &ictx[wq->idxd->type];
+ if (cdev_state == CDEV_NORMAL)
+ cdev_del(&idxd_cdev->cdev);
+ device_unregister(idxd_cdev->dev);
+ /*
+ * The device_type->release() will be called on the device and free
+ * the allocated struct device. We can just forget it.
+ */
+ ida_simple_remove(&cdev_ctx->minor_ida, idxd_cdev->minor);
+ idxd_cdev->dev = NULL;
+ idxd_cdev->minor = -1;
+}
+
+int idxd_wq_add_cdev(struct idxd_wq *wq)
+{
+ struct idxd_cdev *idxd_cdev = &wq->idxd_cdev;
+ struct cdev *cdev = &idxd_cdev->cdev;
+ struct device *dev;
+ int rc;
+
+ rc = idxd_wq_cdev_dev_setup(wq);
+ if (rc < 0)
+ return rc;
+
+ dev = idxd_cdev->dev;
+ cdev_init(cdev, &idxd_cdev_fops);
+ cdev_set_parent(cdev, &dev->kobj);
+ rc = cdev_add(cdev, dev->devt, 1);
+ if (rc) {
+ dev_dbg(&wq->idxd->pdev->dev, "cdev_add failed: %d\n", rc);
+ idxd_wq_cdev_cleanup(wq, CDEV_FAILED);
+ return rc;
+ }
+
+ init_waitqueue_head(&idxd_cdev->err_queue);
+ return 0;
+}
+
+void idxd_wq_del_cdev(struct idxd_wq *wq)
+{
+ idxd_wq_cdev_cleanup(wq, CDEV_NORMAL);
+}
+
+int idxd_cdev_register(void)
+{
+ int rc, i;
+
+ for (i = 0; i < IDXD_TYPE_MAX; i++) {
+ ida_init(&ictx[i].minor_ida);
+ rc = alloc_chrdev_region(&ictx[i].devt, 0, MINORMASK,
+ ictx[i].name);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+void idxd_cdev_remove(void)
+{
+ int i;
+
+ for (i = 0; i < IDXD_TYPE_MAX; i++) {
+ unregister_chrdev_region(ictx[i].devt, MINORMASK);
+ ida_destroy(&ictx[i].minor_ida);
+ }
+}