[PATCHv2 net-next-2.6] ethtool: Added support for FW dump

[Anirban Chakraborty <anirban.chakraborty@qlogic.com>]

Added code to take FW dump via ethtool. A pair of set and get functions are
added to configure dump level and fetch dump data from the driver respectively.

Signed-off-by: Anirban Chakraborty <anirban.chakraborty@qlogic.com>
---
 include/linux/ethtool.h |   31 +++++++++++++++++++++++
 net/core/ethtool.c      |   62 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 93 insertions(+), 0 deletions(-)

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index bd0b50b..f2cd7e1 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -601,6 +601,31 @@ struct ethtool_flash {
 	char	data[ETHTOOL_FLASH_MAX_FILENAME];
 };
 
+/**
+ * struct ethtool_dump - used for retrieving, setting device dump
+ * @type: type of operation, get dump settings or data
+ * @version: FW version of the dump
+ * @flag: flag for dump setting
+ * @len: length of dump data
+ * @data: data collected for this command
+ */
+struct ethtool_dump {
+	__u32	cmd;
+	__u32	type;
+	__u32	version;
+	__u32	flag;
+	__u32	len;
+	u8	data[0];
+};
+
+/*
+ * ethtool_dump_op_type - used to determine type of fetch, flag or data
+ */
+enum ethtool_dump_op_type {
+	ETHTOOL_DUMP_FLAG	= 0,
+	ETHTOOL_DUMP_DATA,
+};
+
 /* for returning and changing feature sets */
 
 /**
@@ -853,6 +878,8 @@ bool ethtool_invalid_flags(struct net_device *dev, u32 data, u32 supported);
  * @get_channels: Get number of channels.
  * @set_channels: Set number of channels.  Returns a negative error code or
  *	zero.
+ * @get_dump: Get dump flag indicating current dump settings of the device
+ * @set_dump: Set dump specific flags to the device
  *
  * All operations are optional (i.e. the function pointer may be set
  * to %NULL) and callers must take this into account.  Callers must
@@ -927,6 +954,8 @@ struct ethtool_ops {
 				  const struct ethtool_rxfh_indir *);
 	void	(*get_channels)(struct net_device *, struct ethtool_channels *);
 	int	(*set_channels)(struct net_device *, struct ethtool_channels *);
+	int	(*get_dump)(struct net_device *, struct ethtool_dump *, void *);
+	int	(*set_dump)(struct net_device *, struct ethtool_dump *);
 
 };
 #endif /* __KERNEL__ */
@@ -998,6 +1027,8 @@ struct ethtool_ops {
 #define ETHTOOL_SFEATURES	0x0000003b /* Change device offload settings */
 #define ETHTOOL_GCHANNELS	0x0000003c /* Get no of channels */
 #define ETHTOOL_SCHANNELS	0x0000003d /* Set no of channels */
+#define ETHTOOL_SET_DUMP	0x0000003e /* Set dump settings */
+#define ETHTOOL_GET_DUMP	0x0000003f /* Get dump settings */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index b6f4058..3c3af8b 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -1823,6 +1823,62 @@ static noinline_for_stack int ethtool_flash_device(struct net_device *dev,
 	return dev->ethtool_ops->flash_device(dev, &efl);
 }
 
+static int ethtool_set_dump(struct net_device *dev,
+			void __user *useraddr)
+{
+	struct ethtool_dump dump;
+
+	if (!dev->ethtool_ops->set_dump)
+		return -EOPNOTSUPP;
+
+	if (copy_from_user(&dump, useraddr, sizeof(dump)))
+		return -EFAULT;
+
+	return dev->ethtool_ops->set_dump(dev, &dump);
+}
+
+static int ethtool_get_dump(struct net_device *dev,
+				void __user *useraddr)
+{
+	int ret;
+	void *data = NULL;
+	struct ethtool_dump dump;
+	const struct ethtool_ops *ops = dev->ethtool_ops;
+	enum ethtool_dump_op_type type;
+
+	if (!dev->ethtool_ops->get_dump)
+		return -EOPNOTSUPP;
+
+	if (copy_from_user(&dump, useraddr, sizeof(dump)))
+		return -EFAULT;
+
+	type = dump.type;
+	dump.type = ETHTOOL_DUMP_FLAG;
+	ret = ops->get_dump(dev, &dump, data);
+	if (ret)
+		return ret;
+	dump.type = type;
+	if (copy_to_user(useraddr, &dump, sizeof(dump)))
+		return -EFAULT;
+	if (type != ETHTOOL_DUMP_DATA)
+		return 0;
+
+	data = vzalloc(dump.len);
+	if (!data)
+		return -ENOMEM;
+	ret = ops->get_dump(dev, &dump, data);
+	if (ret) {
+		ret = -EFAULT;
+		goto out;
+	}
+	useraddr += offsetof(struct ethtool_dump, data);
+	if (copy_to_user(useraddr, data, dump.len))
+		ret = -EFAULT;
+out:
+	vfree(data);
+	return ret;
+}
+
 /* The main entry point in this file.  Called from net/core/dev.c */
 
 int dev_ethtool(struct net *net, struct ifreq *ifr)
@@ -2039,6 +2095,12 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_SCHANNELS:
 		rc = ethtool_set_channels(dev, useraddr);
 		break;
+	case ETHTOOL_SET_DUMP:
+		rc = ethtool_set_dump(dev, useraddr);
+		break;
+	case ETHTOOL_GET_DUMP:
+		rc = ethtool_get_dump(dev, useraddr);
+		break;
 	default:
 		rc = -EOPNOTSUPP;
 	}
-- 
1.7.4.1