OpenCloudOS-Kernel/drivers/dma/idxd/cdev.c

303 lines
6.8 KiB
C

// 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;
wq = inode_wq(inode);
idxd = wq->idxd;
dev = &idxd->pdev->dev;
dev_dbg(dev, "%s called: %d\n", __func__, idxd_wq_refcount(wq));
if (idxd_wq_refcount(wq) > 0 && 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__);
if (rc < 0)
return rc;
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;
kfree(dev);
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");
goto dev_reg_err;
}
idxd_cdev->minor = minor;
return 0;
dev_reg_err:
ida_simple_remove(&cdev_ctx->minor_ida, MINOR(dev->devt));
put_device(dev);
ida_err:
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);
}
}