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

[Hook, Gary]

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

Signed-off-by: Gary R Hook <gary.h...@amd.com>
---
 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);
 }