The WMI chardev API will be removed in the near future.
Reimplement the necessary bits used by this driver so
that userspace software depending on it does no break.
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
drivers/platform/x86/dell/dell-smbios-wmi.c | 161 ++++++++++++++------
1 file changed, 117 insertions(+), 44 deletions(-)
diff --git a/drivers/platform/x86/dell/dell-smbios-wmi.c b/drivers/platform/x86/dell/dell-smbios-wmi.c
index 7eb7c61bb27d..ae9012549560 100644
--- a/drivers/platform/x86/dell/dell-smbios-wmi.c
+++ b/drivers/platform/x86/dell/dell-smbios-wmi.c
@@ -8,11 +8,14 @@
#include <linux/device.h>
#include <linux/dmi.h>
+#include <linux/fs.h>
#include <linux/list.h>
+#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/wmi.h>
+#include <uapi/linux/wmi.h>
#include "dell-smbios.h"
#include "dell-wmi-descriptor.h"
@@ -33,7 +36,8 @@ struct wmi_smbios_priv {
struct list_head list;
struct wmi_device *wdev;
struct device *child;
- u32 req_buf_size;
+ u64 req_buf_size;
+ struct miscdevice char_dev;
};
static LIST_HEAD(wmi_list);
@@ -109,48 +113,115 @@ static int dell_smbios_wmi_call(struct calling_interface_buffer *buffer)
return ret;
}
-static long dell_smbios_wmi_filter(struct wmi_device *wdev, unsigned int cmd,
- struct wmi_ioctl_buffer *arg)
+static int dell_smbios_wmi_open(struct inode *inode, struct file *filp)
{
struct wmi_smbios_priv *priv;
- int ret = 0;
-
- switch (cmd) {
- case DELL_WMI_SMBIOS_CMD:
- mutex_lock(&call_mutex);
- priv = dev_get_drvdata(&wdev->dev);
- if (!priv) {
- ret = -ENODEV;
- goto fail_smbios_cmd;
- }
- memcpy(priv->buf, arg, priv->req_buf_size);
- if (dell_smbios_call_filter(&wdev->dev, &priv->buf->std)) {
- dev_err(&wdev->dev, "Invalid call %d/%d:%8x\n",
- priv->buf->std.cmd_class,
- priv->buf->std.cmd_select,
- priv->buf->std.input[0]);
- ret = -EFAULT;
- goto fail_smbios_cmd;
- }
- ret = run_smbios_call(priv->wdev);
- if (ret)
- goto fail_smbios_cmd;
- memcpy(arg, priv->buf, priv->req_buf_size);
-fail_smbios_cmd:
- mutex_unlock(&call_mutex);
- break;
- default:
- ret = -ENOIOCTLCMD;
+
+ priv = container_of(filp->private_data, struct wmi_smbios_priv, char_dev);
+ filp->private_data = priv;
+
+ return nonseekable_open(inode, filp);
+}
+
+static ssize_t dell_smbios_wmi_read(struct file *filp, char __user *buffer, size_t length,
+ loff_t *offset)
+{
+ struct wmi_smbios_priv *priv = filp->private_data;
+
+ return simple_read_from_buffer(buffer, length, offset, &priv->req_buf_size,
+ sizeof(priv->req_buf_size));
+}
+
+static long dell_smbios_wmi_do_ioctl(struct wmi_smbios_priv *priv,
+ struct dell_wmi_smbios_buffer __user *arg)
+{
+ long ret;
+
+ if (get_user(priv->buf->length, &arg->length))
+ return -EFAULT;
+
+ if (priv->buf->length < priv->req_buf_size)
+ return -EINVAL;
+
+ /* if it's too big, warn, driver will only use what is needed */
+ if (priv->buf->length > priv->req_buf_size)
+ dev_err(&priv->wdev->dev, "Buffer %llu is bigger than required %llu\n",
+ priv->buf->length, priv->req_buf_size);
+
+ if (copy_from_user(priv->buf, arg, priv->req_buf_size))
+ return -EFAULT;
+
+ if (dell_smbios_call_filter(&priv->wdev->dev, &priv->buf->std)) {
+ dev_err(&priv->wdev->dev, "Invalid call %d/%d:%8x\n",
+ priv->buf->std.cmd_class,
+ priv->buf->std.cmd_select,
+ priv->buf->std.input[0]);
+
+ return -EINVAL;
}
+
+ ret = run_smbios_call(priv->wdev);
+ if (ret)
+ return ret;
+
+ if (copy_to_user(arg, priv->buf, priv->req_buf_size))
+ return -EFAULT;
+
+ return 0;
+}
+
+static long dell_smbios_wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ struct dell_wmi_smbios_buffer __user *input = (struct dell_wmi_smbios_buffer __user *)arg;
+ struct wmi_smbios_priv *priv = filp->private_data;
+ long ret;
+
+ if (cmd != DELL_WMI_SMBIOS_CMD)
+ return -ENOIOCTLCMD;
+
+ mutex_lock(&call_mutex);
+ ret = dell_smbios_wmi_do_ioctl(priv, input);
+ mutex_unlock(&call_mutex);
+
return ret;
}
+static const struct file_operations dell_smbios_wmi_fops = {
+ .owner = THIS_MODULE,
+ .open = dell_smbios_wmi_open,
+ .read = dell_smbios_wmi_read,
+ .unlocked_ioctl = dell_smbios_wmi_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+};
+
+static void dell_smbios_wmi_unregister_chardev(void *data)
+{
+ struct miscdevice *char_dev = data;
+
+ misc_deregister(char_dev);
+}
+
+static int dell_smbios_wmi_register_chardev(struct wmi_smbios_priv *priv)
+{
+ int ret;
+
+ priv->char_dev.minor = MISC_DYNAMIC_MINOR;
+ priv->char_dev.name = "wmi/dell-smbios";
+ priv->char_dev.fops = &dell_smbios_wmi_fops;
+ priv->char_dev.mode = 0444;
+
+ ret = misc_register(&priv->char_dev);
+ if (ret < 0)
+ return ret;
+
+ return devm_add_action_or_reset(&priv->wdev->dev, dell_smbios_wmi_unregister_chardev,
+ &priv->char_dev);
+}
+
static int dell_smbios_wmi_probe(struct wmi_device *wdev, const void *context)
{
- struct wmi_driver *wdriver =
- container_of(wdev->dev.driver, struct wmi_driver, driver);
struct wmi_smbios_priv *priv;
- u32 hotfix;
+ u32 buffer_size, hotfix;
int count;
int ret;
@@ -163,39 +234,42 @@ static int dell_smbios_wmi_probe(struct wmi_device *wdev, const void *context)
if (!priv)
return -ENOMEM;
+ priv->wdev = wdev;
+ dev_set_drvdata(&wdev->dev, priv);
+
/* WMI buffer size will be either 4k or 32k depending on machine */
- if (!dell_wmi_get_size(&priv->req_buf_size))
+ if (!dell_wmi_get_size(&buffer_size))
return -EPROBE_DEFER;
+ priv->req_buf_size = buffer_size;
+
/* some SMBIOS calls fail unless BIOS contains hotfix */
if (!dell_wmi_get_hotfix(&hotfix))
return -EPROBE_DEFER;
- if (!hotfix) {
+
+ if (!hotfix)
dev_warn(&wdev->dev,
"WMI SMBIOS userspace interface not supported(%u), try upgrading to a newer BIOS\n",
hotfix);
- wdriver->filter_callback = NULL;
- }
/* add in the length object we will use internally with ioctl */
priv->req_buf_size += sizeof(u64);
- ret = set_required_buffer_size(wdev, priv->req_buf_size);
- if (ret)
- return ret;
count = get_order(priv->req_buf_size);
priv->buf = (void *)devm_get_free_pages(&wdev->dev, GFP_KERNEL, count);
if (!priv->buf)
return -ENOMEM;
+ ret = dell_smbios_wmi_register_chardev(priv);
+ if (ret)
+ return ret;
+
/* ID is used by dell-smbios to set priority of drivers */
wdev->dev.id = 1;
ret = dell_smbios_register_device(&wdev->dev, &dell_smbios_wmi_call);
if (ret)
return ret;
- priv->wdev = wdev;
- dev_set_drvdata(&wdev->dev, priv);
mutex_lock(&list_mutex);
list_add_tail(&priv->list, &wmi_list);
mutex_unlock(&list_mutex);
@@ -250,7 +324,6 @@ static struct wmi_driver dell_smbios_wmi_driver = {
.probe = dell_smbios_wmi_probe,
.remove = dell_smbios_wmi_remove,
.id_table = dell_smbios_wmi_id_table,
- .filter_callback = dell_smbios_wmi_filter,
};
int init_dell_smbios_wmi(void)
--
2.39.2
