[PATCH] staging: wilc1000: Set all options in region debugfs file

From: Chandra S Gorentla
Date: Tue Aug 18 2015 - 13:02:40 EST


This patch allows setting all options in the module's debug region
options file 'wilc_debug_region'. This functionality allows the user
to enable logging from all regions (initialization, locks, firmware
etc.) of the driver. Logging from the following regions is enabled
during the driver initialization:

INIT_DBG, GENERIC_DBG, CFG80211_DBG, FIRM_DBG and HOSTAPD_DBG

Before this change, the numerical value set is equal first byte of
input minus 0x30 (ASCII value of '0'). Because of this, after a write
to this debugfs file, it is difficult to predict the regions on which
logging is enabled.

The DBG_REGION_ALL now includes 3 additional regions TCP_ENH, SPIN_DEBUG
and FIRM_DBG.

Before this change, the region flag FIRM_DBG is enabled during
initialization but cleared after a write to the debugfs file.


Signed-off-by: Chandra S Gorentla <csgorentla@xxxxxxxxx>
---

It is verified by code walk that while generating logs for the flags
TCP_ENH and SPIN_DEBUG code does not try to print strings that are not
terminated by NULL and variables do not try to access invalid
memory locations.

drivers/staging/wilc1000/wilc_debugfs.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/staging/wilc1000/wilc_debugfs.c b/drivers/staging/wilc1000/wilc_debugfs.c
index ae11186..70d98ee 100644
--- a/drivers/staging/wilc1000/wilc_debugfs.c
+++ b/drivers/staging/wilc1000/wilc_debugfs.c
@@ -24,7 +24,10 @@ static struct dentry *wilc_dir;
* --------------------------------------------------------------------------------
*/

-#define DBG_REGION_ALL (GENERIC_DBG | HOSTAPD_DBG | HOSTINF_DBG | CORECONFIG_DBG | CFG80211_DBG | INT_DBG | TX_DBG | RX_DBG | LOCK_DBG | INIT_DBG | BUS_DBG | MEM_DBG)
+#define DBG_REGION_ALL (GENERIC_DBG | HOSTAPD_DBG | HOSTINF_DBG | \
+ CORECONFIG_DBG | CFG80211_DBG | INT_DBG | \
+ TX_DBG | RX_DBG | LOCK_DBG | INIT_DBG | \
+ BUS_DBG | MEM_DBG | TCP_ENH | SPIN_DEBUG | FIRM_DBG)
#define DBG_LEVEL_ALL (DEBUG | INFO | WRN | ERR)
atomic_t REGION = ATOMIC_INIT(INIT_DBG | GENERIC_DBG | CFG80211_DBG | FIRM_DBG | HOSTAPD_DBG);
atomic_t DEBUG_LEVEL = ATOMIC_INIT(ERR);
@@ -87,23 +90,20 @@ static ssize_t wilc_debug_region_read(struct file *file, char __user *userbuf, s
return simple_read_from_buffer(userbuf, count, ppos, buf, res);
}

-static ssize_t wilc_debug_region_write(struct file *filp, const char *buf, size_t count, loff_t *ppos)
+static ssize_t wilc_debug_region_write(struct file *filp,
+ const char __user *buf,
+ size_t count, loff_t *ppos)
{
- char buffer[128] = {};
int flag;
+ int ret;

- if (count > sizeof(buffer))
- return -EINVAL;
-
- if (copy_from_user(buffer, buf, count)) {
- return -EFAULT;
- }
-
- flag = buffer[0] - '0';
+ ret = kstrtouint_from_user(buf, count, 16, &flag);
+ if (ret)
+ return ret;

if (flag > DBG_REGION_ALL) {
printk("%s, value (0x%08x) is out of range, stay previous flag (0x%08x)\n", __func__, flag, atomic_read(&REGION));
- return -EFAULT;
+ return -EINVAL;
}

atomic_set(&REGION, (int)flag);
--
2.5.0

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