target/linux/generic-2.6/patches-2.6.25/923-gpiommc-configfs-locking.patch

   1 The gpiommc configfs context structure needs locking, as configfs
   2 does not lock access between files.
   3
   4 Index: linux-2.6.25.17/drivers/mmc/host/gpiommc.c
   5 ===================================================================
   6 --- linux-2.6.25.17.orig/drivers/mmc/host/gpiommc.c     2008-10-18 23:33:54.000000000 +0200
   7 +++ linux-2.6.25.17/drivers/mmc/host/gpiommc.c  2008-10-18 23:34:33.000000000 +0200
   8 @@ -140,6 +140,8 @@ struct gpiommc_configfs_device {
   9         struct platform_device *pdev;
  10         /* The configuration */
  11         struct gpiommc_platform_data pdata;
  12 +       /* Mutex to protect this structure */
  13 +       struct mutex mutex;
  14  };
  15
  16  #define GPIO_INVALID   -1
  17 @@ -230,6 +232,8 @@ static ssize_t gpiommc_config_attr_show(
  18         unsigned int gpio;
  19         int err = 0;
  20
  21 +       mutex_lock(&dev->mutex);
  22 +
  23         if (attr == &gpiommc_attr_DI) {
  24                 gpio = dev->pdata.pins.gpio_di;
  25                 if (gpio == GPIO_INVALID)
  26 @@ -290,6 +294,8 @@ static ssize_t gpiommc_config_attr_show(
  27         WARN_ON(1);
  28         err = -ENOSYS;
  29  out:
  30 +       mutex_unlock(&dev->mutex);
  31 +
  32         return err ? err : count;
  33  }
  34
  35 @@ -349,6 +355,8 @@ static ssize_t gpiommc_config_attr_store
  36         int err = -EINVAL;
  37         unsigned long data;
  38
  39 +       mutex_lock(&dev->mutex);
  40 +
  41         if (attr == &gpiommc_attr_register) {
  42                 err = strict_strtoul(page, 10, &data);
  43                 if (err)
  44 @@ -474,6 +482,8 @@ static ssize_t gpiommc_config_attr_store
  45         WARN_ON(1);
  46         err = -ENOSYS;
  47  out:
  48 +       mutex_unlock(&dev->mutex);
  49 +
  50         return err ? err : count;
  51  }
  52
  53 @@ -510,6 +520,7 @@ static struct config_item *gpiommc_make_
  54         if (!dev)
  55                 return NULL;
  56
  57 +       mutex_init(&dev->mutex);
  58         config_item_init_type_name(&dev->item, name,
  59                                    &gpiommc_dev_ci_type);
  60