[PATCH] tpm: sysfs owernship changes

In the current driver all sysfs files end up owned by the base driver module
rather than the module that actually owns the device this is a problem if the
module is unloaded and the file is open.  This patch fixes all that and lumps
the files into an attribute_group.
Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Yani Ioannou <yani.ioannou@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/tpm/tpm.c

@@ -208,7 +208,8 @@ static const u8 pcrread[] = {
 	0, 0, 0, 0		/* PCR index */
 };
 
-static ssize_t show_pcrs(struct device *dev, struct device_attribute *attr, char *buf)
+ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
+		      char *buf)
 {
 	u8 data[READ_PCR_RESULT_SIZE];
 	ssize_t len;
@@ -243,7 +244,7 @@ static ssize_t show_pcrs(struct device *dev, struct device_attribute *attr, char
 	return str - buf;
 }
 
-static DEVICE_ATTR(pcrs, S_IRUGO, show_pcrs, NULL);
+EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 
 #define  READ_PUBEK_RESULT_SIZE 314
 static const u8 readpubek[] = {
@@ -252,7 +253,8 @@ static const u8 readpubek[] = {
 	0, 0, 0, 124,		/* TPM_ORD_ReadPubek */
 };
 
-static ssize_t show_pubek(struct device *dev, struct device_attribute *attr, char *buf)
+ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
+		       char *buf)
 {
 	u8 *data;
 	ssize_t len;
@@ -311,7 +313,7 @@ out:
 	return rc;
 }
 
-static DEVICE_ATTR(pubek, S_IRUGO, show_pubek, NULL);
+EXPORT_SYMBOL_GPL(tpm_show_pubek);
 
 #define CAP_VER_RESULT_SIZE 18
 static const u8 cap_version[] = {
@@ -332,7 +334,8 @@ static const u8 cap_manufacturer[] = {
 	0, 0, 1, 3
 };
 
-static ssize_t show_caps(struct device *dev, struct device_attribute *attr, char *buf)
+ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
+		      char *buf)
 {
 	u8 data[sizeof(cap_manufacturer)];
 	ssize_t len;
@@ -365,8 +368,20 @@ static ssize_t show_caps(struct device *dev, struct device_attribute *attr, char
 
 	return str - buf;
 }
+EXPORT_SYMBOL_GPL(tpm_show_caps);
+
+ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+	if (chip == NULL)
+		return 0;
+
+	chip->vendor->cancel(chip);
+	return count;
+}
+EXPORT_SYMBOL_GPL(tpm_store_cancel);
 
-static DEVICE_ATTR(caps, S_IRUGO, show_caps, NULL);
 
 /*
  * Device file system interface to the TPM
@@ -517,9 +532,7 @@ void __devexit tpm_remove(struct pci_dev *pci_dev)
 	pci_set_drvdata(pci_dev, NULL);
 	misc_deregister(&chip->vendor->miscdev);
 
-	device_remove_file(&pci_dev->dev, &dev_attr_pubek);
-	device_remove_file(&pci_dev->dev, &dev_attr_pcrs);
-	device_remove_file(&pci_dev->dev, &dev_attr_caps);
+	sysfs_remove_group(&pci_dev->dev.kobj, chip->vendor->attr_group);
 
 	pci_disable_device(pci_dev);
 
@@ -648,9 +661,7 @@ dev_num_search_complete:
 
 	list_add(&chip->list, &tpm_chip_list);
 
-	device_create_file(&pci_dev->dev, &dev_attr_pubek);
-	device_create_file(&pci_dev->dev, &dev_attr_pcrs);
-	device_create_file(&pci_dev->dev, &dev_attr_caps);
+	sysfs_create_group(&pci_dev->dev.kobj, chip->vendor->attr_group);
 
 	return 0;
 }

drivers/char/tpm/tpm.h

@@ -35,6 +35,14 @@ enum tpm_addr {
 	TPM_DATA = 0x4F
 };
 
+extern ssize_t tpm_show_pubek(struct device *, struct device_attribute *attr,
+				char *);
+extern ssize_t tpm_show_pcrs(struct device *, struct device_attribute *attr,
+				char *);
+extern ssize_t tpm_show_caps(struct device *, struct device_attribute *attr,
+				char *);
+extern ssize_t tpm_store_cancel(struct device *, struct device_attribute *attr,
+				const char *, size_t);
 
 struct tpm_chip;
 
@@ -47,6 +55,7 @@ struct tpm_vendor_specific {
 	int (*send) (struct tpm_chip *, u8 *, size_t);
 	void (*cancel) (struct tpm_chip *);
 	struct miscdevice miscdev;
+	struct attribute_group *attr_group;
 };
 
 struct tpm_chip {

drivers/char/tpm/tpm_atmel.c

@@ -126,6 +126,21 @@ static struct file_operations atmel_ops = {
 	.release = tpm_release,
 };
 
+static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
+static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
+static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
+static DEVICE_ATTR(cancel, S_IWUSR |S_IWGRP, NULL, tpm_store_cancel);
+
+static struct attribute* atmel_attrs[] = {
+	&dev_attr_pubek.attr,
+	&dev_attr_pcrs.attr,
+	&dev_attr_caps.attr,
+	&dev_attr_cancel.attr,
+	0,
+};
+
+static struct attribute_group atmel_attr_grp = { .attrs = atmel_attrs };
+
 static struct tpm_vendor_specific tpm_atmel = {
 	.recv = tpm_atml_recv,
 	.send = tpm_atml_send,
@@ -133,6 +148,7 @@ static struct tpm_vendor_specific tpm_atmel = {
 	.req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,
 	.req_complete_val = ATML_STATUS_DATA_AVAIL,
 	.base = TPM_ATML_BASE,
+	.attr_group = &atmel_attr_grp,
 	.miscdev = { .fops = &atmel_ops, },
 };
 

drivers/char/tpm/tpm_nsc.c

@@ -224,6 +224,21 @@ static struct file_operations nsc_ops = {
 	.release = tpm_release,
 };
 
+static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
+static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
+static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
+static DEVICE_ATTR(cancel, S_IWUSR|S_IWGRP, NULL, tpm_store_cancel);
+
+static struct attribute * nsc_attrs[] = {
+	&dev_attr_pubek.attr,
+	&dev_attr_pcrs.attr,
+	&dev_attr_caps.attr,
+	&dev_attr_cancel.attr,
+	0,
+};
+
+static struct attribute_group nsc_attr_grp = { .attrs = nsc_attrs };
+
 static struct tpm_vendor_specific tpm_nsc = {
 	.recv = tpm_nsc_recv,
 	.send = tpm_nsc_send,
@@ -231,8 +246,8 @@ static struct tpm_vendor_specific tpm_nsc = {
 	.req_complete_mask = NSC_STATUS_OBF,
 	.req_complete_val = NSC_STATUS_OBF,
 	.base = TPM_NSC_BASE,
+	.attr_group = &nsc_attr_grp,
 	.miscdev = { .fops = &nsc_ops, },
-	
 };
 
 static int __devinit tpm_nsc_init(struct pci_dev *pci_dev,