Skip to content

Commit

Permalink
uio: enable per-application notification with ivshemem
Browse files Browse the repository at this point in the history 
  this patch to enable per-application notification support
  when enabling ivhsmem doorbell feature.

Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
  • Loading branch information
@yonghuah
yonghuah committed Oct 14, 2024
1 parent 9b6a2e2 commit 5ccbf7d
Show file tree
Hide file tree
Showing 3 changed files with 102 additions and 33 deletions.
2 changes: 1 addition & 1 deletion drivers/uio/uio.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -574,7 +574,7 @@ static long uio_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
if (!idev->info->ioctl)
return -ENOTTY;

return idev->info->ioctl(idev->info, cmd, arg);
return idev->info->ioctl(idev->info, cmd, arg, (unsigned long)filep);
}
#endif

Expand Down
131 changes: 100 additions & 31 deletions drivers/uio/uio_pci_generic.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -34,9 +34,21 @@
#define DRIVER_DESC "Generic UIO driver for PCI 2.3 devices"

#ifdef CONFIG_PCI_MSI
struct uio_eventfd_info {
unsigned long user;
struct list_head list;
struct eventfd_ctx *evt;
};

struct uio_msix_vector_event {
int irq;
spinlock_t list_lock;
struct list_head evt_list_head;
};

struct uio_msix_info {
struct msix_entry *entries;
struct eventfd_ctx **evts;
struct uio_msix_vector_event *vector_evts;
int nvecs;
};
#endif
Expand All @@ -52,17 +64,24 @@ struct uio_pci_generic_dev {
#ifdef CONFIG_PCI_MSI
static irqreturn_t uio_msix_handler(int irq, void *arg)
{
struct eventfd_ctx *evt = arg;
struct uio_eventfd_info *evt_info;
struct uio_msix_vector_event *vector_evt;

eventfd_signal(evt, 1);
vector_evt = (struct uio_msix_vector_event *)arg;
spin_lock(&vector_evt->list_lock);
list_for_each_entry(evt_info, &vector_evt->evt_list_head, list) {
eventfd_signal(evt_info->evt, 1);
}
spin_unlock(&vector_evt->list_lock);
return IRQ_HANDLED;
}

static int map_msix_eventfd(struct uio_pci_generic_dev *gdev,
int fd, int vector)
unsigned long user, int fd, int vector)
{
int irq, err;
struct eventfd_ctx *evt;
struct uio_eventfd_info *evt_info;
struct uio_msix_vector_event *vector_evt;

/* Passing -1 is used to disable interrupt */
if (fd < 0) {
Expand All @@ -73,30 +92,30 @@ static int map_msix_eventfd(struct uio_pci_generic_dev *gdev,
if (vector >= gdev->msix_info.nvecs)
return -EINVAL;

irq = gdev->msix_info.entries[vector].vector;
evt = gdev->msix_info.evts[vector];
if (evt) {
free_irq(irq, evt);
eventfd_ctx_put(evt);
gdev->msix_info.evts[vector] = NULL;
}

evt = eventfd_ctx_fdget(fd);
if (!evt)
return -EINVAL;

err = request_irq(irq, uio_msix_handler, 0, "UIO IRQ", evt);
if (err) {
evt_info = kzalloc(sizeof(struct uio_eventfd_info), GFP_KERNEL);
if (!evt_info) {
eventfd_ctx_put(evt);
return err;
return -ENOMEM;
}

gdev->msix_info.evts[vector] = evt;
evt_info->evt = evt;
evt_info->user = user;

vector_evt = &(gdev->msix_info.vector_evts[vector]);

spin_lock(&vector_evt->list_lock);
list_add(&evt_info->list, &vector_evt->evt_list_head);
spin_unlock(&vector_evt->list_lock);

return 0;
}

static int uio_msi_ioctl(struct uio_info *info, unsigned int cmd,
unsigned long arg)
unsigned long arg, unsigned long user)
{
struct uio_pci_generic_dev *gdev;
struct uio_msix_data data;
Expand All @@ -109,7 +128,7 @@ static int uio_msi_ioctl(struct uio_info *info, unsigned int cmd,
if (copy_from_user(&data, (void __user *)arg, sizeof(data)))
return -EFAULT;

err = map_msix_eventfd(gdev, data.fd, data.vector);
err = map_msix_eventfd(gdev, user, data.fd, data.vector);
break;
}
default:
Expand All @@ -123,26 +142,54 @@ static int uio_msi_ioctl(struct uio_info *info, unsigned int cmd,
static int pci_generic_init_msix(struct uio_pci_generic_dev *gdev)
{
unsigned char *buffer;
int i, nvecs;
int i, j, irq, nvecs, ret;
struct uio_msix_vector_event *vector_evt;

nvecs = pci_msix_vec_count(gdev->pdev);
if (!nvecs)
return -EINVAL;

buffer = devm_kzalloc(&gdev->pdev->dev, nvecs * (sizeof(struct msix_entry) +
sizeof(struct eventfd_ctx *)), GFP_KERNEL);
sizeof(struct uio_msix_vector_event)), GFP_KERNEL);
if (!buffer)
return -ENOMEM;

gdev->msix_info.entries = (struct msix_entry *)buffer;
gdev->msix_info.evts = (struct eventfd_ctx **)
gdev->msix_info.vector_evts = (struct uio_msix_vector_event *)
((unsigned char *)buffer + nvecs * sizeof(struct msix_entry));
gdev->msix_info.nvecs = nvecs;

for (i = 0; i < nvecs; ++i)
gdev->msix_info.entries[i].entry = i;

return pci_enable_msix_exact(gdev->pdev, gdev->msix_info.entries, nvecs);
ret = pci_enable_msix_exact(gdev->pdev, gdev->msix_info.entries, nvecs);
if (ret) {
pr_err("Failed to enable UIO MSI-X, ret = %d.\n", ret);
kfree(buffer);
return ret;
}

for (i = 0; i < nvecs; ++i) {
irq = gdev->msix_info.entries[i].vector;
vector_evt = &gdev->msix_info.vector_evts[i];
vector_evt->irq = irq;
INIT_LIST_HEAD(&vector_evt->evt_list_head);
spin_lock_init(&vector_evt->list_lock);

ret = request_irq(irq, uio_msix_handler, 0, "UIO IRQ", vector_evt);
if (ret) {

for (j = 0; j < i - 1; j++) {
free_irq(gdev->msix_info.entries[j].vector,
&gdev->msix_info.vector_evts[j]);
}

kfree(buffer);
pci_disable_msix(gdev->pdev);
return ret;
}
}
return 0;
}
#endif

Expand All @@ -156,6 +203,24 @@ static int release(struct uio_info *info, struct inode *inode, unsigned long use
{
struct uio_pci_generic_dev *gdev = to_uio_pci_generic_dev(info);

#ifdef CONFIG_PCI_MSI
int i;
struct uio_eventfd_info *evt_info, *next;
struct uio_msix_vector_event *vector_evt;

for (i = 0; i < gdev->msix_info.nvecs; ++i) {
vector_evt = &gdev->msix_info.vector_evts[i];
spin_lock(&vector_evt->list_lock);
list_for_each_entry_safe(evt_info, next, &vector_evt->evt_list_head, list) {
if (evt_info->user == user) {
list_del(&evt_info->list);
eventfd_ctx_put(evt_info->evt);
kfree(evt_info);
}
}
spin_unlock(&vector_evt->list_lock);
}
#endif
/*
* This driver is insecure when used with devices doing DMA, but some
 * people (mis)use it with such devices.
Expand Down Expand Up @@ -269,21 +334,25 @@ static int probe(struct pci_dev *pdev,
#ifdef CONFIG_PCI_MSI
static void remove(struct pci_dev *pdev)
{
int i, irq;
struct eventfd_ctx *evt;
int i;
struct uio_eventfd_info *evt_info, *next;
struct uio_msix_vector_event *vector_evt;
struct uio_pci_generic_dev *gdev = pci_get_drvdata(pdev);

if (gdev->msix_info.entries != NULL) {
for (i = 0; i < gdev->msix_info.nvecs; i++) {
irq = gdev->msix_info.entries[i].vector;
evt = gdev->msix_info.evts[i];
if (evt) {
free_irq(irq, evt);
eventfd_ctx_put(evt);
gdev->msix_info.evts[i] = NULL;
vector_evt = &gdev->msix_info.vector_evts[i];
spin_lock(&vector_evt->list_lock);
list_for_each_entry_safe(evt_info, next, &vector_evt->evt_list_head, list) {
list_del(&evt_info->list);
eventfd_ctx_put(evt_info->evt);
kfree(evt_info);
}
spin_unlock(&vector_evt->list_lock);
free_irq(vector_evt->irq, vector_evt);
}
pci_disable_msix(pdev);
kfree(gdev->msix_info.entries);
}
}
#endif
Expand Down
2 changes: 1 addition & 1 deletion include/linux/uio_driver.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -123,7 +123,7 @@ struct uio_info {
int (*irqcontrol)(struct uio_info *info, s32 irq_on);
#ifdef CONFIG_PCI_MSI
int (*ioctl)(struct uio_info *info, unsigned int cmd,
unsigned long arg);
unsigned long arg, unsigned long user);
#endif
ANDROID_KABI_RESERVE(1);
};
Expand Down

0 comments on commit 5ccbf7d

Please sign in to comment.