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-rw-r--r--drivers/char/tpm/tpm.c96
-rw-r--r--drivers/char/tpm/tpm.h3
-rw-r--r--drivers/char/tpm/tpm_tis.c14
3 files changed, 61 insertions, 52 deletions
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index ae766d86845..1fee7034a38 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -954,72 +954,63 @@ EXPORT_SYMBOL_GPL(tpm_store_cancel);
/*
* Device file system interface to the TPM
+ *
+ * It's assured that the chip will be opened just once,
+ * by the check of is_open variable, which is protected
+ * by driver_lock.
*/
int tpm_open(struct inode *inode, struct file *file)
{
- int rc = 0, minor = iminor(inode);
+ int minor = iminor(inode);
struct tpm_chip *chip = NULL, *pos;
- lock_kernel();
- spin_lock(&driver_lock);
-
- list_for_each_entry(pos, &tpm_chip_list, list) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
if (pos->vendor.miscdev.minor == minor) {
chip = pos;
+ get_device(chip->dev);
break;
}
}
+ rcu_read_unlock();
- if (chip == NULL) {
- rc = -ENODEV;
- goto err_out;
- }
+ if (!chip)
+ return -ENODEV;
- if (chip->num_opens) {
+ if (test_and_set_bit(0, &chip->is_open)) {
dev_dbg(chip->dev, "Another process owns this TPM\n");
- rc = -EBUSY;
- goto err_out;
+ put_device(chip->dev);
+ return -EBUSY;
}
- chip->num_opens++;
- get_device(chip->dev);
-
- spin_unlock(&driver_lock);
-
chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
if (chip->data_buffer == NULL) {
- chip->num_opens--;
+ clear_bit(0, &chip->is_open);
put_device(chip->dev);
- unlock_kernel();
return -ENOMEM;
}
atomic_set(&chip->data_pending, 0);
file->private_data = chip;
- unlock_kernel();
return 0;
-
-err_out:
- spin_unlock(&driver_lock);
- unlock_kernel();
- return rc;
}
EXPORT_SYMBOL_GPL(tpm_open);
+/*
+ * Called on file close
+ */
int tpm_release(struct inode *inode, struct file *file)
{
struct tpm_chip *chip = file->private_data;
+ del_singleshot_timer_sync(&chip->user_read_timer);
flush_scheduled_work();
- spin_lock(&driver_lock);
file->private_data = NULL;
- del_singleshot_timer_sync(&chip->user_read_timer);
atomic_set(&chip->data_pending, 0);
- chip->num_opens--;
- put_device(chip->dev);
kfree(chip->data_buffer);
- spin_unlock(&driver_lock);
+ clear_bit(0, &chip->is_open);
+ put_device(chip->dev);
return 0;
}
EXPORT_SYMBOL_GPL(tpm_release);
@@ -1093,13 +1084,11 @@ void tpm_remove_hardware(struct device *dev)
}
spin_lock(&driver_lock);
-
- list_del(&chip->list);
-
+ list_del_rcu(&chip->list);
spin_unlock(&driver_lock);
+ synchronize_rcu();
misc_deregister(&chip->vendor.miscdev);
-
sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
tpm_bios_log_teardown(chip->bios_dir);
@@ -1144,25 +1133,33 @@ int tpm_pm_resume(struct device *dev)
}
EXPORT_SYMBOL_GPL(tpm_pm_resume);
+/* In case vendor provided release function, call it too.*/
+
+void tpm_dev_vendor_release(struct tpm_chip *chip)
+{
+ if (chip->vendor.release)
+ chip->vendor.release(chip->dev);
+
+ clear_bit(chip->dev_num, dev_mask);
+ kfree(chip->vendor.miscdev.name);
+}
+EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
+
+
/*
* Once all references to platform device are down to 0,
* release all allocated structures.
- * In case vendor provided release function,
- * call it too.
*/
static void tpm_dev_release(struct device *dev)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
- if (chip->vendor.release)
- chip->vendor.release(dev);
+ tpm_dev_vendor_release(chip);
chip->release(dev);
-
- clear_bit(chip->dev_num, dev_mask);
- kfree(chip->vendor.miscdev.name);
kfree(chip);
}
+EXPORT_SYMBOL_GPL(tpm_dev_release);
/*
* Called from tpm_<specific>.c probe function only for devices
@@ -1171,8 +1168,8 @@ static void tpm_dev_release(struct device *dev)
* upon errant exit from this function specific probe function should call
* pci_disable_device
*/
-struct tpm_chip *tpm_register_hardware(struct device *dev, const struct tpm_vendor_specific
- *entry)
+struct tpm_chip *tpm_register_hardware(struct device *dev,
+ const struct tpm_vendor_specific *entry)
{
#define DEVNAME_SIZE 7
@@ -1231,21 +1228,20 @@ struct tpm_chip *tpm_register_hardware(struct device *dev, const struct tpm_vend
return NULL;
}
- spin_lock(&driver_lock);
-
- list_add(&chip->list, &tpm_chip_list);
-
- spin_unlock(&driver_lock);
-
if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
- list_del(&chip->list);
misc_deregister(&chip->vendor.miscdev);
put_device(chip->dev);
+
return NULL;
}
chip->bios_dir = tpm_bios_log_setup(devname);
+ /* Make chip available */
+ spin_lock(&driver_lock);
+ list_add_rcu(&chip->list, &tpm_chip_list);
+ spin_unlock(&driver_lock);
+
return chip;
}
EXPORT_SYMBOL_GPL(tpm_register_hardware);
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index e885148b4cf..8e30df4a438 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -90,7 +90,7 @@ struct tpm_chip {
struct device *dev; /* Device stuff */
int dev_num; /* /dev/tpm# */
- int num_opens; /* only one allowed */
+ unsigned long is_open; /* only one allowed */
int time_expired;
/* Data passed to and from the tpm via the read/write calls */
@@ -132,6 +132,7 @@ extern struct tpm_chip* tpm_register_hardware(struct device *,
const struct tpm_vendor_specific *);
extern int tpm_open(struct inode *, struct file *);
extern int tpm_release(struct inode *, struct file *);
+extern void tpm_dev_vendor_release(struct tpm_chip *);
extern ssize_t tpm_write(struct file *, const char __user *, size_t,
loff_t *);
extern ssize_t tpm_read(struct file *, char __user *, size_t, loff_t *);
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index ed1879c0dd8..717af7ad1bd 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -630,12 +630,23 @@ static struct pnp_device_id tpm_pnp_tbl[] __devinitdata = {
{"", 0} /* Terminator */
};
+static __devexit void tpm_tis_pnp_remove(struct pnp_dev *dev)
+{
+ struct tpm_chip *chip = pnp_get_drvdata(dev);
+
+ tpm_dev_vendor_release(chip);
+
+ kfree(chip);
+}
+
+
static struct pnp_driver tis_pnp_driver = {
.name = "tpm_tis",
.id_table = tpm_pnp_tbl,
.probe = tpm_tis_pnp_init,
.suspend = tpm_tis_pnp_suspend,
.resume = tpm_tis_pnp_resume,
+ .remove = tpm_tis_pnp_remove,
};
#define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
@@ -683,6 +694,7 @@ static void __exit cleanup_tis(void)
spin_lock(&tis_lock);
list_for_each_entry_safe(i, j, &tis_chips, list) {
chip = to_tpm_chip(i);
+ tpm_remove_hardware(chip->dev);
iowrite32(~TPM_GLOBAL_INT_ENABLE &
ioread32(chip->vendor.iobase +
TPM_INT_ENABLE(chip->vendor.
@@ -694,9 +706,9 @@ static void __exit cleanup_tis(void)
free_irq(chip->vendor.irq, chip);
iounmap(i->iobase);
list_del(&i->list);
- tpm_remove_hardware(chip->dev);
}
spin_unlock(&tis_lock);
+
if (force) {
platform_device_unregister(pdev);
driver_unregister(&tis_drv);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-26 06:19:01 +0000