diff options
Diffstat (limited to 'drivers/platform/x86/dell/dell-smbios-wmi.c')
-rw-r--r-- | drivers/platform/x86/dell/dell-smbios-wmi.c | 173 |
1 files changed, 120 insertions, 53 deletions
diff --git a/drivers/platform/x86/dell/dell-smbios-wmi.c b/drivers/platform/x86/dell/dell-smbios-wmi.c index 931cc50136..ae90125495 100644 --- a/drivers/platform/x86/dell/dell-smbios-wmi.c +++ b/drivers/platform/x86/dell/dell-smbios-wmi.c @@ -6,12 +6,16 @@ */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#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" @@ -32,7 +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); @@ -108,48 +113,115 @@ out_wmi_call: 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; @@ -162,62 +234,58 @@ 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 *)__get_free_pages(GFP_KERNEL, count); + 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) - goto fail_register; + 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); return 0; - -fail_register: - free_pages((unsigned long)priv->buf, count); - return ret; } static void dell_smbios_wmi_remove(struct wmi_device *wdev) { struct wmi_smbios_priv *priv = dev_get_drvdata(&wdev->dev); - int count; mutex_lock(&call_mutex); mutex_lock(&list_mutex); list_del(&priv->list); mutex_unlock(&list_mutex); dell_smbios_unregister_device(&wdev->dev); - count = get_order(priv->req_buf_size); - free_pages((unsigned long)priv->buf, count); mutex_unlock(&call_mutex); } @@ -256,7 +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) |