Contributors: 45
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Hans-Jürgen Koch |
3032 |
62.79% |
5 |
6.76% |
| Xiubo Li |
314 |
6.50% |
4 |
5.41% |
| Hamish Martin |
255 |
5.28% |
2 |
2.70% |
| Greg Kroah-Hartman |
195 |
4.04% |
6 |
8.11% |
| Eric W. Biedermann |
184 |
3.81% |
4 |
5.41% |
| Brandon Philips |
141 |
2.92% |
1 |
1.35% |
| Alexandru Ardelean |
126 |
2.61% |
1 |
1.35% |
| Uwe Kleine-König |
93 |
1.93% |
2 |
2.70% |
| Zhaolong Zhang |
51 |
1.06% |
1 |
1.35% |
| Linus Torvalds |
50 |
1.04% |
3 |
4.05% |
| Jonathan Corbet |
48 |
0.99% |
2 |
2.70% |
| Dan Carpenter |
46 |
0.95% |
3 |
4.05% |
| Stephen Hemminger |
32 |
0.66% |
3 |
4.05% |
| Hillf Danton |
31 |
0.64% |
2 |
2.70% |
| Ben Hutchings |
27 |
0.56% |
1 |
1.35% |
| LiuJian |
25 |
0.52% |
2 |
2.70% |
| Alexandre Belloni |
20 |
0.41% |
1 |
1.35% |
| Tejun Heo |
19 |
0.39% |
2 |
2.70% |
| Andrew G. Harvey |
17 |
0.35% |
1 |
1.35% |
| Ian Abbott |
16 |
0.33% |
1 |
1.35% |
| Cong Ding |
12 |
0.25% |
1 |
1.35% |
| Brian Russell |
10 |
0.21% |
1 |
1.35% |
| Nicholas Piggin |
10 |
0.21% |
1 |
1.35% |
| Jean-Samuel Chenard |
9 |
0.19% |
1 |
1.35% |
| Johannes Thumshirn |
6 |
0.12% |
1 |
1.35% |
| Kai Jiang |
6 |
0.12% |
1 |
1.35% |
| Arnd Bergmann |
5 |
0.10% |
1 |
1.35% |
| Wanlong Gao |
5 |
0.10% |
1 |
1.35% |
| Michal Hocko |
5 |
0.10% |
1 |
1.35% |
| Michal Simek |
5 |
0.10% |
1 |
1.35% |
| Suman Anna |
4 |
0.08% |
1 |
1.35% |
| Dave Jiang |
4 |
0.08% |
1 |
1.35% |
| Damian Hobson-Garcia |
4 |
0.08% |
1 |
1.35% |
| Cristian Stoica |
4 |
0.08% |
1 |
1.35% |
| Alexey Dobriyan |
3 |
0.06% |
2 |
2.70% |
| Li Bin |
3 |
0.06% |
1 |
1.35% |
| Souptick Joarder |
2 |
0.04% |
2 |
2.70% |
| Emese Revfy |
2 |
0.04% |
1 |
1.35% |
| Jan Engelhardt |
2 |
0.04% |
1 |
1.35% |
| Ingo Molnar |
1 |
0.02% |
1 |
1.35% |
| Wei Yongjun |
1 |
0.02% |
1 |
1.35% |
| Chengguang Xu |
1 |
0.02% |
1 |
1.35% |
| Al Viro |
1 |
0.02% |
1 |
1.35% |
| Michal Sojka |
1 |
0.02% |
1 |
1.35% |
| Liu hailong |
1 |
0.02% |
1 |
1.35% |
| Total |
4829 |
|
74 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* drivers/uio/uio.c
*
* Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
* Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
* Copyright(C) 2006, Hans J. Koch <hjk@hansjkoch.de>
* Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
*
* Userspace IO
*
* Base Functions
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/idr.h>
#include <linux/sched/signal.h>
#include <linux/string.h>
#include <linux/kobject.h>
#include <linux/cdev.h>
#include <linux/uio_driver.h>
#define UIO_MAX_DEVICES (1U << MINORBITS)
static int uio_major;
static struct cdev *uio_cdev;
static DEFINE_IDR(uio_idr);
static const struct file_operations uio_fops;
/* Protect idr accesses */
static DEFINE_MUTEX(minor_lock);
/*
* attributes
*/
struct uio_map {
struct kobject kobj;
struct uio_mem *mem;
};
#define to_map(map) container_of(map, struct uio_map, kobj)
static ssize_t map_name_show(struct uio_mem *mem, char *buf)
{
if (unlikely(!mem->name))
mem->name = "";
return sprintf(buf, "%s\n", mem->name);
}
static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
{
return sprintf(buf, "%pa\n", &mem->addr);
}
static ssize_t map_size_show(struct uio_mem *mem, char *buf)
{
return sprintf(buf, "%pa\n", &mem->size);
}
static ssize_t map_offset_show(struct uio_mem *mem, char *buf)
{
return sprintf(buf, "0x%llx\n", (unsigned long long)mem->offs);
}
struct map_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct uio_mem *, char *);
ssize_t (*store)(struct uio_mem *, const char *, size_t);
};
static struct map_sysfs_entry name_attribute =
__ATTR(name, S_IRUGO, map_name_show, NULL);
static struct map_sysfs_entry addr_attribute =
__ATTR(addr, S_IRUGO, map_addr_show, NULL);
static struct map_sysfs_entry size_attribute =
__ATTR(size, S_IRUGO, map_size_show, NULL);
static struct map_sysfs_entry offset_attribute =
__ATTR(offset, S_IRUGO, map_offset_show, NULL);
static struct attribute *attrs[] = {
&name_attribute.attr,
&addr_attribute.attr,
&size_attribute.attr,
&offset_attribute.attr,
NULL, /* need to NULL terminate the list of attributes */
};
static void map_release(struct kobject *kobj)
{
struct uio_map *map = to_map(kobj);
kfree(map);
}
static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
struct uio_map *map = to_map(kobj);
struct uio_mem *mem = map->mem;
struct map_sysfs_entry *entry;
entry = container_of(attr, struct map_sysfs_entry, attr);
if (!entry->show)
return -EIO;
return entry->show(mem, buf);
}
static const struct sysfs_ops map_sysfs_ops = {
.show = map_type_show,
};
static struct kobj_type map_attr_type = {
.release = map_release,
.sysfs_ops = &map_sysfs_ops,
.default_attrs = attrs,
};
struct uio_portio {
struct kobject kobj;
struct uio_port *port;
};
#define to_portio(portio) container_of(portio, struct uio_portio, kobj)
static ssize_t portio_name_show(struct uio_port *port, char *buf)
{
if (unlikely(!port->name))
port->name = "";
return sprintf(buf, "%s\n", port->name);
}
static ssize_t portio_start_show(struct uio_port *port, char *buf)
{
return sprintf(buf, "0x%lx\n", port->start);
}
static ssize_t portio_size_show(struct uio_port *port, char *buf)
{
return sprintf(buf, "0x%lx\n", port->size);
}
static ssize_t portio_porttype_show(struct uio_port *port, char *buf)
{
const char *porttypes[] = {"none", "x86", "gpio", "other"};
if ((port->porttype < 0) || (port->porttype > UIO_PORT_OTHER))
return -EINVAL;
return sprintf(buf, "port_%s\n", porttypes[port->porttype]);
}
struct portio_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct uio_port *, char *);
ssize_t (*store)(struct uio_port *, const char *, size_t);
};
static struct portio_sysfs_entry portio_name_attribute =
__ATTR(name, S_IRUGO, portio_name_show, NULL);
static struct portio_sysfs_entry portio_start_attribute =
__ATTR(start, S_IRUGO, portio_start_show, NULL);
static struct portio_sysfs_entry portio_size_attribute =
__ATTR(size, S_IRUGO, portio_size_show, NULL);
static struct portio_sysfs_entry portio_porttype_attribute =
__ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
static struct attribute *portio_attrs[] = {
&portio_name_attribute.attr,
&portio_start_attribute.attr,
&portio_size_attribute.attr,
&portio_porttype_attribute.attr,
NULL,
};
static void portio_release(struct kobject *kobj)
{
struct uio_portio *portio = to_portio(kobj);
kfree(portio);
}
static ssize_t portio_type_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
struct uio_portio *portio = to_portio(kobj);
struct uio_port *port = portio->port;
struct portio_sysfs_entry *entry;
entry = container_of(attr, struct portio_sysfs_entry, attr);
if (!entry->show)
return -EIO;
return entry->show(port, buf);
}
static const struct sysfs_ops portio_sysfs_ops = {
.show = portio_type_show,
};
static struct kobj_type portio_attr_type = {
.release = portio_release,
.sysfs_ops = &portio_sysfs_ops,
.default_attrs = portio_attrs,
};
static ssize_t name_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uio_device *idev = dev_get_drvdata(dev);
int ret;
mutex_lock(&idev->info_lock);
if (!idev->info) {
ret = -EINVAL;
dev_err(dev, "the device has been unregistered\n");
goto out;
}
ret = sprintf(buf, "%s\n", idev->info->name);
out:
mutex_unlock(&idev->info_lock);
return ret;
}
static DEVICE_ATTR_RO(name);
static ssize_t version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uio_device *idev = dev_get_drvdata(dev);
int ret;
mutex_lock(&idev->info_lock);
if (!idev->info) {
ret = -EINVAL;
dev_err(dev, "the device has been unregistered\n");
goto out;
}
ret = sprintf(buf, "%s\n", idev->info->version);
out:
mutex_unlock(&idev->info_lock);
return ret;
}
static DEVICE_ATTR_RO(version);
static ssize_t event_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct uio_device *idev = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", (unsigned int)atomic_read(&idev->event));
}
static DEVICE_ATTR_RO(event);
static struct attribute *uio_attrs[] = {
&dev_attr_name.attr,
&dev_attr_version.attr,
&dev_attr_event.attr,
NULL,
};
ATTRIBUTE_GROUPS(uio);
/* UIO class infrastructure */
static struct class uio_class = {
.name = "uio",
.dev_groups = uio_groups,
};
static bool uio_class_registered;
/*
* device functions
*/
static int uio_dev_add_attributes(struct uio_device *idev)
{
int ret;
int mi, pi;
int map_found = 0;
int portio_found = 0;
struct uio_mem *mem;
struct uio_map *map;
struct uio_port *port;
struct uio_portio *portio;
for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
mem = &idev->info->mem[mi];
if (mem->size == 0)
break;
if (!map_found) {
map_found = 1;
idev->map_dir = kobject_create_and_add("maps",
&idev->dev.kobj);
if (!idev->map_dir) {
ret = -ENOMEM;
goto err_map;
}
}
map = kzalloc(sizeof(*map), GFP_KERNEL);
if (!map) {
ret = -ENOMEM;
goto err_map;
}
kobject_init(&map->kobj, &map_attr_type);
map->mem = mem;
mem->map = map;
ret = kobject_add(&map->kobj, idev->map_dir, "map%d", mi);
if (ret)
goto err_map_kobj;
ret = kobject_uevent(&map->kobj, KOBJ_ADD);
if (ret)
goto err_map_kobj;
}
for (pi = 0; pi < MAX_UIO_PORT_REGIONS; pi++) {
port = &idev->info->port[pi];
if (port->size == 0)
break;
if (!portio_found) {
portio_found = 1;
idev->portio_dir = kobject_create_and_add("portio",
&idev->dev.kobj);
if (!idev->portio_dir) {
ret = -ENOMEM;
goto err_portio;
}
}
portio = kzalloc(sizeof(*portio), GFP_KERNEL);
if (!portio) {
ret = -ENOMEM;
goto err_portio;
}
kobject_init(&portio->kobj, &portio_attr_type);
portio->port = port;
port->portio = portio;
ret = kobject_add(&portio->kobj, idev->portio_dir,
"port%d", pi);
if (ret)
goto err_portio_kobj;
ret = kobject_uevent(&portio->kobj, KOBJ_ADD);
if (ret)
goto err_portio_kobj;
}
return 0;
err_portio:
pi--;
err_portio_kobj:
for (; pi >= 0; pi--) {
port = &idev->info->port[pi];
portio = port->portio;
kobject_put(&portio->kobj);
}
kobject_put(idev->portio_dir);
err_map:
mi--;
err_map_kobj:
for (; mi >= 0; mi--) {
mem = &idev->info->mem[mi];
map = mem->map;
kobject_put(&map->kobj);
}
kobject_put(idev->map_dir);
dev_err(&idev->dev, "error creating sysfs files (%d)\n", ret);
return ret;
}
static void uio_dev_del_attributes(struct uio_device *idev)
{
int i;
struct uio_mem *mem;
struct uio_port *port;
for (i = 0; i < MAX_UIO_MAPS; i++) {
mem = &idev->info->mem[i];
if (mem->size == 0)
break;
kobject_put(&mem->map->kobj);
}
kobject_put(idev->map_dir);
for (i = 0; i < MAX_UIO_PORT_REGIONS; i++) {
port = &idev->info->port[i];
if (port->size == 0)
break;
kobject_put(&port->portio->kobj);
}
kobject_put(idev->portio_dir);
}
static int uio_get_minor(struct uio_device *idev)
{
int retval = -ENOMEM;
mutex_lock(&minor_lock);
retval = idr_alloc(&uio_idr, idev, 0, UIO_MAX_DEVICES, GFP_KERNEL);
if (retval >= 0) {
idev->minor = retval;
retval = 0;
} else if (retval == -ENOSPC) {
dev_err(&idev->dev, "too many uio devices\n");
retval = -EINVAL;
}
mutex_unlock(&minor_lock);
return retval;
}
static void uio_free_minor(struct uio_device *idev)
{
mutex_lock(&minor_lock);
idr_remove(&uio_idr, idev->minor);
mutex_unlock(&minor_lock);
}
/**
* uio_event_notify - trigger an interrupt event
* @info: UIO device capabilities
*/
void uio_event_notify(struct uio_info *info)
{
struct uio_device *idev = info->uio_dev;
atomic_inc(&idev->event);
wake_up_interruptible(&idev->wait);
kill_fasync(&idev->async_queue, SIGIO, POLL_IN);
}
EXPORT_SYMBOL_GPL(uio_event_notify);
/**
* uio_interrupt - hardware interrupt handler
* @irq: IRQ number, can be UIO_IRQ_CYCLIC for cyclic timer
* @dev_id: Pointer to the devices uio_device structure
*/
static irqreturn_t uio_interrupt(int irq, void *dev_id)
{
struct uio_device *idev = (struct uio_device *)dev_id;
irqreturn_t ret;
ret = idev->info->handler(irq, idev->info);
if (ret == IRQ_HANDLED)
uio_event_notify(idev->info);
return ret;
}
struct uio_listener {
struct uio_device *dev;
s32 event_count;
};
static int uio_open(struct inode *inode, struct file *filep)
{
struct uio_device *idev;
struct uio_listener *listener;
int ret = 0;
mutex_lock(&minor_lock);
idev = idr_find(&uio_idr, iminor(inode));
mutex_unlock(&minor_lock);
if (!idev) {
ret = -ENODEV;
goto out;
}
get_device(&idev->dev);
if (!try_module_get(idev->owner)) {
ret = -ENODEV;
goto err_module_get;
}
listener = kmalloc(sizeof(*listener), GFP_KERNEL);
if (!listener) {
ret = -ENOMEM;
goto err_alloc_listener;
}
listener->dev = idev;
listener->event_count = atomic_read(&idev->event);
filep->private_data = listener;
mutex_lock(&idev->info_lock);
if (!idev->info) {
mutex_unlock(&idev->info_lock);
ret = -EINVAL;
goto err_infoopen;
}
if (idev->info->open)
ret = idev->info->open(idev->info, inode);
mutex_unlock(&idev->info_lock);
if (ret)
goto err_infoopen;
return 0;
err_infoopen:
kfree(listener);
err_alloc_listener:
module_put(idev->owner);
err_module_get:
put_device(&idev->dev);
out:
return ret;
}
static int uio_fasync(int fd, struct file *filep, int on)
{
struct uio_listener *listener = filep->private_data;
struct uio_device *idev = listener->dev;
return fasync_helper(fd, filep, on, &idev->async_queue);
}
static int uio_release(struct inode *inode, struct file *filep)
{
int ret = 0;
struct uio_listener *listener = filep->private_data;
struct uio_device *idev = listener->dev;
mutex_lock(&idev->info_lock);
if (idev->info && idev->info->release)
ret = idev->info->release(idev->info, inode);
mutex_unlock(&idev->info_lock);
module_put(idev->owner);
kfree(listener);
put_device(&idev->dev);
return ret;
}
static __poll_t uio_poll(struct file *filep, poll_table *wait)
{
struct uio_listener *listener = filep->private_data;
struct uio_device *idev = listener->dev;
__poll_t ret = 0;
mutex_lock(&idev->info_lock);
if (!idev->info || !idev->info->irq)
ret = -EIO;
mutex_unlock(&idev->info_lock);
if (ret)
return ret;
poll_wait(filep, &idev->wait, wait);
if (listener->event_count != atomic_read(&idev->event))
return EPOLLIN | EPOLLRDNORM;
return 0;
}
static ssize_t uio_read(struct file *filep, char __user *buf,
size_t count, loff_t *ppos)
{
struct uio_listener *listener = filep->private_data;
struct uio_device *idev = listener->dev;
DECLARE_WAITQUEUE(wait, current);
ssize_t retval = 0;
s32 event_count;
if (count != sizeof(s32))
return -EINVAL;
add_wait_queue(&idev->wait, &wait);
do {
mutex_lock(&idev->info_lock);
if (!idev->info || !idev->info->irq) {
retval = -EIO;
mutex_unlock(&idev->info_lock);
break;
}
mutex_unlock(&idev->info_lock);
set_current_state(TASK_INTERRUPTIBLE);
event_count = atomic_read(&idev->event);
if (event_count != listener->event_count) {
__set_current_state(TASK_RUNNING);
if (copy_to_user(buf, &event_count, count))
retval = -EFAULT;
else {
listener->event_count = event_count;
retval = count;
}
break;
}
if (filep->f_flags & O_NONBLOCK) {
retval = -EAGAIN;
break;
}
if (signal_pending(current)) {
retval = -ERESTARTSYS;
break;
}
schedule();
} while (1);
__set_current_state(TASK_RUNNING);
remove_wait_queue(&idev->wait, &wait);
return retval;
}
static ssize_t uio_write(struct file *filep, const char __user *buf,
size_t count, loff_t *ppos)
{
struct uio_listener *listener = filep->private_data;
struct uio_device *idev = listener->dev;
ssize_t retval;
s32 irq_on;
if (count != sizeof(s32))
return -EINVAL;
if (copy_from_user(&irq_on, buf, count))
return -EFAULT;
mutex_lock(&idev->info_lock);
if (!idev->info) {
retval = -EINVAL;
goto out;
}
if (!idev->info->irq) {
retval = -EIO;
goto out;
}
if (!idev->info->irqcontrol) {
retval = -ENOSYS;
goto out;
}
retval = idev->info->irqcontrol(idev->info, irq_on);
out:
mutex_unlock(&idev->info_lock);
return retval ? retval : sizeof(s32);
}
static int uio_find_mem_index(struct vm_area_struct *vma)
{
struct uio_device *idev = vma->vm_private_data;
if (vma->vm_pgoff < MAX_UIO_MAPS) {
if (idev->info->mem[vma->vm_pgoff].size == 0)
return -1;
return (int)vma->vm_pgoff;
}
return -1;
}
static vm_fault_t uio_vma_fault(struct vm_fault *vmf)
{
struct uio_device *idev = vmf->vma->vm_private_data;
struct page *page;
unsigned long offset;
void *addr;
vm_fault_t ret = 0;
int mi;
mutex_lock(&idev->info_lock);
if (!idev->info) {
ret = VM_FAULT_SIGBUS;
goto out;
}
mi = uio_find_mem_index(vmf->vma);
if (mi < 0) {
ret = VM_FAULT_SIGBUS;
goto out;
}
/*
* We need to subtract mi because userspace uses offset = N*PAGE_SIZE
* to use mem[N].
*/
offset = (vmf->pgoff - mi) << PAGE_SHIFT;
addr = (void *)(unsigned long)idev->info->mem[mi].addr + offset;
if (idev->info->mem[mi].memtype == UIO_MEM_LOGICAL)
page = virt_to_page(addr);
else
page = vmalloc_to_page(addr);
get_page(page);
vmf->page = page;
out:
mutex_unlock(&idev->info_lock);
return ret;
}
static const struct vm_operations_struct uio_logical_vm_ops = {
.fault = uio_vma_fault,
};
static int uio_mmap_logical(struct vm_area_struct *vma)
{
vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_ops = &uio_logical_vm_ops;
return 0;
}
static const struct vm_operations_struct uio_physical_vm_ops = {
#ifdef CONFIG_HAVE_IOREMAP_PROT
.access = generic_access_phys,
#endif
};
static int uio_mmap_physical(struct vm_area_struct *vma)
{
struct uio_device *idev = vma->vm_private_data;
int mi = uio_find_mem_index(vma);
struct uio_mem *mem;
if (mi < 0)
return -EINVAL;
mem = idev->info->mem + mi;
if (mem->addr & ~PAGE_MASK)
return -ENODEV;
if (vma->vm_end - vma->vm_start > mem->size)
return -EINVAL;
vma->vm_ops = &uio_physical_vm_ops;
if (idev->info->mem[mi].memtype == UIO_MEM_PHYS)
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
/*
* We cannot use the vm_iomap_memory() helper here,
* because vma->vm_pgoff is the map index we looked
* up above in uio_find_mem_index(), rather than an
* actual page offset into the mmap.
*
* So we just do the physical mmap without a page
* offset.
*/
return remap_pfn_range(vma,
vma->vm_start,
mem->addr >> PAGE_SHIFT,
vma->vm_end - vma->vm_start,
vma->vm_page_prot);
}
static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
{
struct uio_listener *listener = filep->private_data;
struct uio_device *idev = listener->dev;
int mi;
unsigned long requested_pages, actual_pages;
int ret = 0;
if (vma->vm_end < vma->vm_start)
return -EINVAL;
vma->vm_private_data = idev;
mutex_lock(&idev->info_lock);
if (!idev->info) {
ret = -EINVAL;
goto out;
}
mi = uio_find_mem_index(vma);
if (mi < 0) {
ret = -EINVAL;
goto out;
}
requested_pages = vma_pages(vma);
actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK)
+ idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
if (requested_pages > actual_pages) {
ret = -EINVAL;
goto out;
}
if (idev->info->mmap) {
ret = idev->info->mmap(idev->info, vma);
goto out;
}
switch (idev->info->mem[mi].memtype) {
case UIO_MEM_IOVA:
case UIO_MEM_PHYS:
ret = uio_mmap_physical(vma);
break;
case UIO_MEM_LOGICAL:
case UIO_MEM_VIRTUAL:
ret = uio_mmap_logical(vma);
break;
default:
ret = -EINVAL;
}
out:
mutex_unlock(&idev->info_lock);
return ret;
}
static const struct file_operations uio_fops = {
.owner = THIS_MODULE,
.open = uio_open,
.release = uio_release,
.read = uio_read,
.write = uio_write,
.mmap = uio_mmap,
.poll = uio_poll,
.fasync = uio_fasync,
.llseek = noop_llseek,
};
static int uio_major_init(void)
{
static const char name[] = "uio";
struct cdev *cdev = NULL;
dev_t uio_dev = 0;
int result;
result = alloc_chrdev_region(&uio_dev, 0, UIO_MAX_DEVICES, name);
if (result)
goto out;
result = -ENOMEM;
cdev = cdev_alloc();
if (!cdev)
goto out_unregister;
cdev->owner = THIS_MODULE;
cdev->ops = &uio_fops;
kobject_set_name(&cdev->kobj, "%s", name);
result = cdev_add(cdev, uio_dev, UIO_MAX_DEVICES);
if (result)
goto out_put;
uio_major = MAJOR(uio_dev);
uio_cdev = cdev;
return 0;
out_put:
kobject_put(&cdev->kobj);
out_unregister:
unregister_chrdev_region(uio_dev, UIO_MAX_DEVICES);
out:
return result;
}
static void uio_major_cleanup(void)
{
unregister_chrdev_region(MKDEV(uio_major, 0), UIO_MAX_DEVICES);
cdev_del(uio_cdev);
}
static int init_uio_class(void)
{
int ret;
/* This is the first time in here, set everything up properly */
ret = uio_major_init();
if (ret)
goto exit;
ret = class_register(&uio_class);
if (ret) {
printk(KERN_ERR "class_register failed for uio\n");
goto err_class_register;
}
uio_class_registered = true;
return 0;
err_class_register:
uio_major_cleanup();
exit:
return ret;
}
static void release_uio_class(void)
{
uio_class_registered = false;
class_unregister(&uio_class);
uio_major_cleanup();
}
static void uio_device_release(struct device *dev)
{
struct uio_device *idev = dev_get_drvdata(dev);
kfree(idev);
}
/**
* uio_register_device - register a new userspace IO device
* @owner: module that creates the new device
* @parent: parent device
* @info: UIO device capabilities
*
* returns zero on success or a negative error code.
*/
int __uio_register_device(struct module *owner,
struct device *parent,
struct uio_info *info)
{
struct uio_device *idev;
int ret = 0;
if (!uio_class_registered)
return -EPROBE_DEFER;
if (!parent || !info || !info->name || !info->version)
return -EINVAL;
info->uio_dev = NULL;
idev = kzalloc(sizeof(*idev), GFP_KERNEL);
if (!idev) {
return -ENOMEM;
}
idev->owner = owner;
idev->info = info;
mutex_init(&idev->info_lock);
init_waitqueue_head(&idev->wait);
atomic_set(&idev->event, 0);
ret = uio_get_minor(idev);
if (ret) {
kfree(idev);
return ret;
}
device_initialize(&idev->dev);
idev->dev.devt = MKDEV(uio_major, idev->minor);
idev->dev.class = &uio_class;
idev->dev.parent = parent;
idev->dev.release = uio_device_release;
dev_set_drvdata(&idev->dev, idev);
ret = dev_set_name(&idev->dev, "uio%d", idev->minor);
if (ret)
goto err_device_create;
ret = device_add(&idev->dev);
if (ret)
goto err_device_create;
ret = uio_dev_add_attributes(idev);
if (ret)
goto err_uio_dev_add_attributes;
info->uio_dev = idev;
if (info->irq && (info->irq != UIO_IRQ_CUSTOM)) {
/*
* Note that we deliberately don't use devm_request_irq
* here. The parent module can unregister the UIO device
* and call pci_disable_msi, which requires that this
* irq has been freed. However, the device may have open
* FDs at the time of unregister and therefore may not be
* freed until they are released.
*/
ret = request_irq(info->irq, uio_interrupt,
info->irq_flags, info->name, idev);
if (ret) {
info->uio_dev = NULL;
goto err_request_irq;
}
}
return 0;
err_request_irq:
uio_dev_del_attributes(idev);
err_uio_dev_add_attributes:
device_del(&idev->dev);
err_device_create:
uio_free_minor(idev);
put_device(&idev->dev);
return ret;
}
EXPORT_SYMBOL_GPL(__uio_register_device);
static void devm_uio_unregister_device(struct device *dev, void *res)
{
uio_unregister_device(*(struct uio_info **)res);
}
/**
* devm_uio_register_device - Resource managed uio_register_device()
* @owner: module that creates the new device
* @parent: parent device
* @info: UIO device capabilities
*
* returns zero on success or a negative error code.
*/
int __devm_uio_register_device(struct module *owner,
struct device *parent,
struct uio_info *info)
{
struct uio_info **ptr;
int ret;
ptr = devres_alloc(devm_uio_unregister_device, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return -ENOMEM;
*ptr = info;
ret = __uio_register_device(owner, parent, info);
if (ret) {
devres_free(ptr);
return ret;
}
devres_add(parent, ptr);
return 0;
}
EXPORT_SYMBOL_GPL(__devm_uio_register_device);
/**
* uio_unregister_device - unregister a industrial IO device
* @info: UIO device capabilities
*
*/
void uio_unregister_device(struct uio_info *info)
{
struct uio_device *idev;
if (!info || !info->uio_dev)
return;
idev = info->uio_dev;
uio_free_minor(idev);
mutex_lock(&idev->info_lock);
uio_dev_del_attributes(idev);
if (info->irq && info->irq != UIO_IRQ_CUSTOM)
free_irq(info->irq, idev);
idev->info = NULL;
mutex_unlock(&idev->info_lock);
wake_up_interruptible(&idev->wait);
kill_fasync(&idev->async_queue, SIGIO, POLL_HUP);
device_unregister(&idev->dev);
return;
}
EXPORT_SYMBOL_GPL(uio_unregister_device);
static int __init uio_init(void)
{
return init_uio_class();
}
static void __exit uio_exit(void)
{
release_uio_class();
idr_destroy(&uio_idr);
}
module_init(uio_init)
module_exit(uio_exit)
MODULE_LICENSE("GPL v2");