[PATCH 09/11] crypto: ccp - expose pcibus module parameter in debugfs

["Hook, Gary" <Gary.Hook@xxxxxxx>]

Add module parameter pcibus as a read-only variable to the CCP's
debugfs info.

Signed-off-by: Gary R Hook <gary.hook@xxxxxxx>
---
 drivers/crypto/ccp/ccp-debugfs.c |    1 +
 drivers/crypto/ccp/ccp-dev.h     |    1 +
 drivers/crypto/ccp/sp-pci.c      |   47 ++++++++++++++++++++++++++++++++++++--
 3 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/ccp/ccp-debugfs.c b/drivers/crypto/ccp/ccp-debugfs.c
index c4cc0e60fd50..7a223b71eee8 100644
--- a/drivers/crypto/ccp/ccp-debugfs.c
+++ b/drivers/crypto/ccp/ccp-debugfs.c
@@ -318,6 +318,7 @@ void ccp5_debugfs_setup(struct ccp_device *ccp)
 	}
 
 	ccp_debugfs_register_modparams(ccp_debugfs_dir);
+	ccp_debugfs_register_buses(ccp_debugfs_dir);
 
 	return;
 }
diff --git a/drivers/crypto/ccp/ccp-dev.h b/drivers/crypto/ccp/ccp-dev.h
index d812446213ee..cd1bd78d95cc 100644
--- a/drivers/crypto/ccp/ccp-dev.h
+++ b/drivers/crypto/ccp/ccp-dev.h
@@ -683,6 +683,7 @@ typedef struct _modparam {
                 umode_t parammode;
         } modparam_t;
 extern void ccp_debugfs_register_modparams(struct dentry *parentdir);
+extern void ccp_debugfs_register_buses(struct dentry *parentdir);
 
 #endif
 
diff --git a/drivers/crypto/ccp/sp-pci.c b/drivers/crypto/ccp/sp-pci.c
index a563d85b242e..86dee2a66f00 100644
--- a/drivers/crypto/ccp/sp-pci.c
+++ b/drivers/crypto/ccp/sp-pci.c
@@ -62,6 +62,7 @@ static void ccp_parse_pci_buses(void)
 {
 	unsigned int busno;
 	unsigned int eos = 0;
+	char *busarg;
 	int ret;
 	char *comma;
 	char *tok;
@@ -70,7 +71,9 @@ static void ccp_parse_pci_buses(void)
 	if (!buses)
 		return;
 
-	comma = tok = buses;
+	busarg = kstrdup(buses, GFP_KERNEL);
+
+	comma = tok = busarg;
 	while (!eos && *tok && (n_pcibus < MAXCCPS)) {
 		while (*comma && *comma != COMMA)
 			comma++;
@@ -81,11 +84,15 @@ static void ccp_parse_pci_buses(void)
 		ret = kstrtouint(tok, 0, &busno);
 		if (ret) {
 			pr_info("%s: Parsing error (%d) '%s'\n", __func__, ret, buses);
-			return;
+			n_pcibus = 0; /* pretend there was no parameter */
+			goto err;
 		}
 		pcibus[n_pcibus++] = busno;
 		tok = ++comma;
 	}
+
+err:
+	kfree(busarg);
 }
 
 #ifdef CONFIG_CRYPTO_DEV_CCP_DEBUGFS
@@ -106,6 +113,41 @@ void ccp_debugfs_register_modparams(struct dentry *parentdir)
 				   moduleparameters[j].param);
 }
 
+static ssize_t ccp_debugfs_buses_read(struct file *filp, char __user *ubuf,
+				      size_t count, loff_t *offp)
+{
+	char *string = filp->private_data;
+	unsigned int oboff = 0;
+	unsigned plen = 1023;
+	ssize_t ret;
+	char *obuf;
+
+	if (!string)
+		string = "(ALL)";
+	obuf = kmalloc(plen + 1, GFP_KERNEL);
+	if (!obuf)
+		return -ENOMEM;
+
+	oboff += snprintf(obuf, plen, "%s\n", string);
+
+	ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
+	kfree(obuf);
+
+	return ret;
+}
+
+static const struct file_operations ccp_debugfs_char_ops = {
+	.owner = THIS_MODULE,
+	.open = simple_open,
+	.read = ccp_debugfs_buses_read,
+	.write = NULL,
+};
+
+void ccp_debugfs_register_buses(struct dentry *parentdir)
+{
+        debugfs_create_file("buses", S_IRUSR, parentdir, buses, &ccp_debugfs_char_ops);
+}
+
 #endif
 
 unsigned int ccp_get_nqueues_param(void) {
@@ -457,6 +499,7 @@ static struct pci_driver sp_pci_driver = {
 int sp_pci_init(void)
 {
         mutex_init(&devcount_mutex);
+	ccp_parse_pci_buses();
 	return pci_register_driver(&sp_pci_driver);
 }