staging: lustre: Dynamic LNet Configuration (DLC) IOCTL changes

This is the fourth patch of a set of patches that enables DLC.

This patch changes the IOCTL infrastructure in preparation of
adding extra IOCTL communication between user and kernel space.
The changes include:
- adding a common header to be passed to ioctl infra functions
  instead of passing an exact structure.  This header is meant
  to be included in all structures to be passed through that
  interface.  The IOCTL handler casts this header to a particular
  type that it expects
- All sanity testing on the past in structure is performed in the
  generic ioctl infrastructure code.
- All ioctl handlers changed to take the header instead of a
  particular structure type

Signed-off-by: Amir Shehata <amir.shehata@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2456
Reviewed-on: http://review.whamcloud.com/8021
Reviewed-by: Doug Oucharek <doug.s.oucharek@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 12 insertions, 11 deletions

diff --git a/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h b/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h
index e4463ad..0598702 100644
--- a/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h
+++ b/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h
@@ -43,9 +43,13 @@
 
 #define LIBCFS_IOCTL_VERSION 0x0001000a
 
-struct libcfs_ioctl_data {
+struct libcfs_ioctl_hdr {
 	__u32 ioc_len;
 	__u32 ioc_version;
+};
+
+struct libcfs_ioctl_data {
+	struct libcfs_ioctl_hdr ioc_hdr;
 
 	__u64 ioc_nid;
 	__u64 ioc_u64[1];
@@ -70,11 +74,6 @@ struct libcfs_ioctl_data {
 
 #define ioc_priority ioc_u32[0]
 
-struct libcfs_ioctl_hdr {
-	__u32 ioc_len;
-	__u32 ioc_version;
-};
-
 struct libcfs_debug_ioctl_data {
 	struct libcfs_ioctl_hdr hdr;
 	unsigned int subs;
@@ -90,7 +89,7 @@ do {						    \
 
 struct libcfs_ioctl_handler {
 	struct list_head item;
-	int (*handle_ioctl)(unsigned int cmd, struct libcfs_ioctl_data *data);
+	int (*handle_ioctl)(unsigned int cmd, struct libcfs_ioctl_hdr *hdr);
 };
 
 #define DECLARE_IOCTL_HANDLER(ident, func)		      \
@@ -148,9 +147,9 @@ static inline int libcfs_ioctl_packlen(struct libcfs_ioctl_data *data)
 	return len;
 }
 
-static inline int libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
+static inline bool libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
 {
-	if (data->ioc_len > (1<<30)) {
+	if (data->ioc_hdr.ioc_len > (1 << 30)) {
 		CERROR("LIBCFS ioctl: ioc_len larger than 1<<30\n");
 		return 1;
 	}
@@ -186,7 +185,7 @@ static inline int libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
 		CERROR("LIBCFS ioctl: plen2 nonzero but no pbuf2 pointer\n");
 		return 1;
 	}
-	if ((__u32)libcfs_ioctl_packlen(data) != data->ioc_len) {
+	if ((__u32)libcfs_ioctl_packlen(data) != data->ioc_hdr.ioc_len) {
 		CERROR("LIBCFS ioctl: packlen != ioc_len\n");
 		return 1;
 	}
@@ -206,7 +205,9 @@ static inline int libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
 
 int libcfs_register_ioctl(struct libcfs_ioctl_handler *hand);
 int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand);
-int libcfs_ioctl_getdata(char *buf, char *end, void __user *arg);
+int libcfs_ioctl_getdata_len(const struct libcfs_ioctl_hdr __user *arg,
+			     __u32 *buf_len);
 int libcfs_ioctl_popdata(void __user *arg, void *buf, int size);
+int libcfs_ioctl_data_adjust(struct libcfs_ioctl_data *data);
 
 #endif /* __LIBCFS_IOCTL_H__ */