staging: vme: mmap() support for vme_user
We also make sure that user won't be able to reconfigure the window while it is mmap'ed. Signed-off-by: Dmitry Kalinkin <dmitry.kalinkin@gmail.com> Cc: Martyn Welch <martyn.welch@ge.com> Cc: Igor Alekseev <igor.alekseev@itep.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Родитель
0cd189a42d
Коммит
c74a804f11
|
@ -17,6 +17,7 @@
|
|||
|
||||
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
||||
|
||||
#include <linux/atomic.h>
|
||||
#include <linux/cdev.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/device.h>
|
||||
|
@ -99,6 +100,7 @@ struct image_desc {
|
|||
struct device *device; /* Sysfs device */
|
||||
struct vme_resource *resource; /* VME resource */
|
||||
int users; /* Number of current users */
|
||||
int mmap_count; /* Number of current mmap's */
|
||||
};
|
||||
static struct image_desc image[VME_DEVS];
|
||||
|
||||
|
@ -134,6 +136,10 @@ static ssize_t vme_user_write(struct file *, const char __user *, size_t,
|
|||
loff_t *);
|
||||
static loff_t vme_user_llseek(struct file *, loff_t, int);
|
||||
static long vme_user_unlocked_ioctl(struct file *, unsigned int, unsigned long);
|
||||
static int vme_user_mmap(struct file *file, struct vm_area_struct *vma);
|
||||
|
||||
static void vme_user_vm_open(struct vm_area_struct *vma);
|
||||
static void vme_user_vm_close(struct vm_area_struct *vma);
|
||||
|
||||
static int vme_user_match(struct vme_dev *);
|
||||
static int vme_user_probe(struct vme_dev *);
|
||||
|
@ -147,6 +153,17 @@ static const struct file_operations vme_user_fops = {
|
|||
.llseek = vme_user_llseek,
|
||||
.unlocked_ioctl = vme_user_unlocked_ioctl,
|
||||
.compat_ioctl = vme_user_unlocked_ioctl,
|
||||
.mmap = vme_user_mmap,
|
||||
};
|
||||
|
||||
struct vme_user_vma_priv {
|
||||
unsigned int minor;
|
||||
atomic_t refcnt;
|
||||
};
|
||||
|
||||
static const struct vm_operations_struct vme_user_vm_ops = {
|
||||
.open = vme_user_vm_open,
|
||||
.close = vme_user_vm_close,
|
||||
};
|
||||
|
||||
|
||||
|
@ -488,6 +505,11 @@ static int vme_user_ioctl(struct inode *inode, struct file *file,
|
|||
|
||||
case VME_SET_MASTER:
|
||||
|
||||
if (image[minor].mmap_count != 0) {
|
||||
pr_warn("Can't adjust mapped window\n");
|
||||
return -EPERM;
|
||||
}
|
||||
|
||||
copied = copy_from_user(&master, argp, sizeof(master));
|
||||
if (copied != 0) {
|
||||
pr_warn("Partial copy from userspace\n");
|
||||
|
@ -564,6 +586,69 @@ vme_user_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static void vme_user_vm_open(struct vm_area_struct *vma)
|
||||
{
|
||||
struct vme_user_vma_priv *vma_priv = vma->vm_private_data;
|
||||
|
||||
atomic_inc(&vma_priv->refcnt);
|
||||
}
|
||||
|
||||
static void vme_user_vm_close(struct vm_area_struct *vma)
|
||||
{
|
||||
struct vme_user_vma_priv *vma_priv = vma->vm_private_data;
|
||||
unsigned int minor = vma_priv->minor;
|
||||
|
||||
if (!atomic_dec_and_test(&vma_priv->refcnt))
|
||||
return;
|
||||
|
||||
mutex_lock(&image[minor].mutex);
|
||||
image[minor].mmap_count--;
|
||||
mutex_unlock(&image[minor].mutex);
|
||||
|
||||
kfree(vma_priv);
|
||||
}
|
||||
|
||||
static int vme_user_master_mmap(unsigned int minor, struct vm_area_struct *vma)
|
||||
{
|
||||
int err;
|
||||
struct vme_user_vma_priv *vma_priv;
|
||||
|
||||
mutex_lock(&image[minor].mutex);
|
||||
|
||||
err = vme_master_mmap(image[minor].resource, vma);
|
||||
if (err) {
|
||||
mutex_unlock(&image[minor].mutex);
|
||||
return err;
|
||||
}
|
||||
|
||||
vma_priv = kmalloc(sizeof(struct vme_user_vma_priv), GFP_KERNEL);
|
||||
if (vma_priv == NULL) {
|
||||
mutex_unlock(&image[minor].mutex);
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
vma_priv->minor = minor;
|
||||
atomic_set(&vma_priv->refcnt, 1);
|
||||
vma->vm_ops = &vme_user_vm_ops;
|
||||
vma->vm_private_data = vma_priv;
|
||||
|
||||
image[minor].mmap_count++;
|
||||
|
||||
mutex_unlock(&image[minor].mutex);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int vme_user_mmap(struct file *file, struct vm_area_struct *vma)
|
||||
{
|
||||
unsigned int minor = MINOR(file_inode(file)->i_rdev);
|
||||
|
||||
if (type[minor] == MASTER_MINOR)
|
||||
return vme_user_master_mmap(minor, vma);
|
||||
|
||||
return -ENODEV;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Unallocate a previously allocated buffer
|
||||
|
|
|
@ -609,6 +609,32 @@ unsigned int vme_master_rmw(struct vme_resource *resource, unsigned int mask,
|
|||
}
|
||||
EXPORT_SYMBOL(vme_master_rmw);
|
||||
|
||||
int vme_master_mmap(struct vme_resource *resource, struct vm_area_struct *vma)
|
||||
{
|
||||
struct vme_master_resource *image;
|
||||
phys_addr_t phys_addr;
|
||||
unsigned long vma_size;
|
||||
|
||||
if (resource->type != VME_MASTER) {
|
||||
pr_err("Not a master resource\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
image = list_entry(resource->entry, struct vme_master_resource, list);
|
||||
phys_addr = image->bus_resource.start + (vma->vm_pgoff << PAGE_SHIFT);
|
||||
vma_size = vma->vm_end - vma->vm_start;
|
||||
|
||||
if (phys_addr + vma_size > image->bus_resource.end + 1) {
|
||||
pr_err("Map size cannot exceed the window size\n");
|
||||
return -EFAULT;
|
||||
}
|
||||
|
||||
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
|
||||
|
||||
return vm_iomap_memory(vma, phys_addr, vma->vm_end - vma->vm_start);
|
||||
}
|
||||
EXPORT_SYMBOL(vme_master_mmap);
|
||||
|
||||
void vme_master_free(struct vme_resource *resource)
|
||||
{
|
||||
struct vme_master_resource *master_image;
|
||||
|
|
|
@ -137,6 +137,7 @@ ssize_t vme_master_read(struct vme_resource *, void *, size_t, loff_t);
|
|||
ssize_t vme_master_write(struct vme_resource *, void *, size_t, loff_t);
|
||||
unsigned int vme_master_rmw(struct vme_resource *, unsigned int, unsigned int,
|
||||
unsigned int, loff_t);
|
||||
int vme_master_mmap(struct vme_resource *resource, struct vm_area_struct *vma);
|
||||
void vme_master_free(struct vme_resource *);
|
||||
|
||||
struct vme_resource *vme_dma_request(struct vme_dev *, u32);
|
||||
|
|
Загрузка…
Ссылка в новой задаче