[PATCH 12/12] staging: usbip: usbip_common.h: reorganize and document request headers

matt mooney
2011-05-11T08:54:24Z

Document the request header structures; move #defines out of the
structures; organize function declarations by source file; and move
inline functions to the end of file.

Signed-off-by: matt mooney <mfm@muteddisk.com>
---
drivers/staging/usbip/usbip_common.h | 236 +++++++++++++++++-----------------
1 files changed, 121 insertions(+), 115 deletions(-)

diff --git a/drivers/staging/usbip/usbip_common.h b/drivers/staging/usbip/usbip_common.h
index 83f8c1e..074ac42 100644
--- a/drivers/staging/usbip/usbip_common.h
+++ b/drivers/staging/usbip/usbip_common.h
@@ -104,111 +104,110 @@ extern struct device_attribute dev_attr_usbip_debug;
usbip_dbg_with_flag(usbip_debug_stub_tx, fmt , ##args)

/*
- * USB/IP request headers.
- * Currently, we define 4 request types:
+ * USB/IP request headers
*
- * - CMD_SUBMIT transfers a USB request, corresponding to usb_submit_urb().
- * (client to server)
- * - RET_RETURN transfers the result of CMD_SUBMIT.
- * (server to client)
- * - CMD_UNLINK transfers an unlink request of a pending USB request.
+ * Each request is transferred across the network to its counterpart, which
+ * facilitates the normal USB communication. The values contained in the headers
+ * are basically the same as in a URB. Currently, four request types are
+ * defined:
+ *
+ * - USBIP_CMD_SUBMIT: a USB request block, corresponds to usb_submit_urb()
* (client to server)
- * - RET_UNLINK transfers the result of CMD_UNLINK.
+ *
+ * - USBIP_RET_SUBMIT: the result of USBIP_CMD_SUBMIT
* (server to client)
*
- * Note: The below request formats are based on the USB subsystem of Linux. Its
- * details will be defined when other implementations come.
+ * - USBIP_CMD_UNLINK: an unlink request of a pending USBIP_CMD_SUBMIT,
+ * corresponds to usb_unlink_urb()
+ * (client to server)
*
+ * - USBIP_RET_UNLINK: the result of USBIP_CMD_UNLINK
+ * (server to client)
*
*/
+#define USBIP_CMD_SUBMIT 0x0001
+#define USBIP_RET_SUBMIT 0x0002
+#define USBIP_CMD_UNLINK 0x0003
+#define USBIP_RET_UNLINK 0x0004

-/*
- * A basic header followed by other additional headers.
+#define USBIP_DIR_IN 0x00
+#define USBIP_DIR_OUT 0x01
+
+/**
+ * struct usbip_header_basic - data pertinent to every request
+ * @command: the usbip request type
+ * @seqnum: sequential number that identifies requests; incremented per
+ * connection
+ * @devid: specifies a remote USB device uniquely instead of busnum and devnum;
+ * in the stub driver, this value is ((busnum << 16) | devnum)
+ * @direction: direction of the transfer
+ * @ep: endpoint number
*/
struct usbip_header_basic {
-#define USBIP_CMD_SUBMIT 0x0001
-#define USBIP_CMD_UNLINK 0x0002
-#define USBIP_RET_SUBMIT 0x0003
-#define USBIP_RET_UNLINK 0x0004
__u32 command;
-
- /* sequential number which identifies requests.
- * incremented per connections */
__u32 seqnum;
-
- /* devid is used to specify a remote USB device uniquely instead
- * of busnum and devnum in Linux. In the case of Linux stub_driver,
- * this value is ((busnum << 16) | devnum) */
__u32 devid;
-
-#define USBIP_DIR_OUT 0
-#define USBIP_DIR_IN 1
__u32 direction;
- __u32 ep; /* endpoint number */
+ __u32 ep;
} __packed;

-/*
- * An additional header for a CMD_SUBMIT packet.
+/**
+ * struct usbip_header_cmd_submit - USBIP_CMD_SUBMIT packet header
+ * @transfer_flags: URB flags
+ * @transfer_buffer_length: the data size for (in) or (out) transfer
+ * @start_frame: initial frame for isochronous or interrupt transfers
+ * @number_of_packets: number of isochronous packets
+ * @interval: maximum time for the request on the server-side host controller
+ * @setup: setup data for a control request
*/
struct usbip_header_cmd_submit {
- /* these values are basically the same as in a URB. */
-
- /* the same in a URB. */
__u32 transfer_flags;
-
- /* set the following data size (out),
- * or expected reading data size (in) */
__s32 transfer_buffer_length;

/* it is difficult for usbip to sync frames (reserved only?) */
__s32 start_frame;
-
- /* the number of iso descriptors that follows this header */
__s32 number_of_packets;
-
- /* the maximum time within which this request works in a host
- * controller of a server side */
__s32 interval;

- /* set setup packet data for a CTRL request */
unsigned char setup[8];
} __packed;

-/*
- * An additional header for a RET_SUBMIT packet.
+/**
+ * struct usbip_header_ret_submit - USBIP_RET_SUBMIT packet header
+ * @status: return status of a non-iso request
+ * @actual_length: number of bytes transferred
+ * @start_frame: initial frame for isochronous or interrupt transfers
+ * @number_of_packets: number of isochronous packets
+ * @error_count: number of errors for isochronous transfers
*/
struct usbip_header_ret_submit {
__s32 status;
- __s32 actual_length; /* returned data length */
- __s32 start_frame; /* ISO and INT */
- __s32 number_of_packets; /* ISO only */
- __s32 error_count; /* ISO only */
+ __s32 actual_length;
+ __s32 start_frame;
+ __s32 number_of_packets;
+ __s32 error_count;
} __packed;

-/*
- * An additional header for a CMD_UNLINK packet.
+/**
+ * struct usbip_header_cmd_unlink - USBIP_CMD_UNLINK packet header
+ * @seqnum: the URB seqnum to unlink
*/
struct usbip_header_cmd_unlink {
- __u32 seqnum; /* URB's seqnum that will be unlinked */
+ __u32 seqnum;
} __packed;

-/*
- * An additional header for a RET_UNLINK packet.
+/**
+ * struct usbip_header_ret_unlink - USBIP_RET_UNLINK packet header
+ * @status: return status of the request
*/
struct usbip_header_ret_unlink {
__s32 status;
} __packed;

-/* the same as usb_iso_packet_descriptor but packed for pdu */
-struct usbip_iso_packet_descriptor {
- __u32 offset;
- __u32 length; /* expected length */
- __u32 actual_length;
- __u32 status;
-} __packed;
-
-/*
- * All usbip packets use a common header to keep code simple.
+/**
+ * struct usbip_header - common header for all usbip packets
+ * @base: the basic header
+ * @u: packet type dependent header
*/
struct usbip_header {
struct usbip_header_basic base;
@@ -221,40 +220,15 @@ struct usbip_header {
} u;
} __packed;

-int usbip_xmit(int, struct socket *, char *, int, int);
-int usbip_sendmsg(struct socket *, struct msghdr *, int);
-
-static inline int interface_to_busnum(struct usb_interface *interface)
-{
- struct usb_device *udev = interface_to_usbdev(interface);
- return udev->bus->busnum;
-}
-
-static inline int interface_to_devnum(struct usb_interface *interface)
-{
- struct usb_device *udev = interface_to_usbdev(interface);
- return udev->devnum;
-}
-
-static inline int interface_to_infnum(struct usb_interface *interface)
-{
- return interface->cur_altsetting->desc.bInterfaceNumber;
-}
-
-#if 0
-int setnodelay(struct socket *);
-int setquickack(struct socket *);
-int setkeepalive(struct socket *socket);
-void setreuse(struct socket *);
-#endif
-
-struct socket *sockfd_to_socket(unsigned int);
-int set_sockaddr(struct socket *socket, struct sockaddr_storage *ss);
-
-void usbip_dump_urb(struct urb *purb);
-void usbip_dump_header(struct usbip_header *pdu);
-
-struct usbip_device;
+/*
+ * This is the same as usb_iso_packet_descriptor but packed for pdu.
+ */
+struct usbip_iso_packet_descriptor {
+ __u32 offset;
+ __u32 length; /* expected length */
+ __u32 actual_length;
+ __u32 status;
+} __packed;

enum usbip_side {
USBIP_VHCI,
@@ -277,20 +251,7 @@ enum usbip_status {
VDEV_ST_ERROR
};

-/* a common structure for stub_device and vhci_device */
-struct usbip_device {
- enum usbip_side side;
- enum usbip_status status;
-
- /* lock for status */
- spinlock_t lock;
-
- struct socket *tcp_socket;
-
- struct task_struct *tcp_rx;
- struct task_struct *tcp_tx;
-
- /* event handler */
+/* event handler */
#define USBIP_EH_SHUTDOWN (1 << 0)
#define USBIP_EH_BYE (1 << 1)
#define USBIP_EH_RESET (1 << 2)
@@ -307,6 +268,19 @@ struct usbip_device {
#define VDEV_EVENT_ERROR_TCP (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define VDEV_EVENT_ERROR_MALLOC (USBIP_EH_SHUTDOWN | USBIP_EH_UNUSABLE)

+/* a common structure for stub_device and vhci_device */
+struct usbip_device {
+ enum usbip_side side;
+ enum usbip_status status;
+
+ /* lock for status */
+ spinlock_t lock;
+
+ struct socket *tcp_socket;
+
+ struct task_struct *tcp_rx;
+ struct task_struct *tcp_tx;
+
unsigned long event;
struct task_struct *eh;
wait_queue_head_t eh_waitq;
@@ -318,17 +292,32 @@ struct usbip_device {
} eh_ops;
};

+#if 0
+int usbip_sendmsg(struct socket *, struct msghdr *, int);
+int set_sockaddr(struct socket *socket, struct sockaddr_storage *ss);
+int setnodelay(struct socket *);
+int setquickack(struct socket *);
+int setkeepalive(struct socket *socket);
+void setreuse(struct socket *);
+#endif
+
+/* usbip_common.c */
+void usbip_dump_urb(struct urb *purb);
+void usbip_dump_header(struct usbip_header *pdu);
+
+int usbip_xmit(int send, struct socket *sock, char *buf, int size,
+ int msg_flags);
+struct socket *sockfd_to_socket(unsigned int sockfd);
+
void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
int pack);
-
void usbip_header_correct_endian(struct usbip_header *pdu, int send);
-/* some members of urb must be substituted before. */
-int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb);
+
+void *usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen);
/* some members of urb must be substituted before. */
int usbip_recv_iso(struct usbip_device *ud, struct urb *urb);
-/* some members of urb must be substituted before. */
int usbip_pad_iso(struct usbip_device *ud, struct urb *urb);
-void *usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen);
+int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb);

/* usbip_event.c */
int usbip_start_eh(struct usbip_device *ud);
@@ -336,4 +325,21 @@ void usbip_stop_eh(struct usbip_device *ud);
void usbip_event_add(struct usbip_device *ud, unsigned long event);
int usbip_event_happened(struct usbip_device *ud);

+static inline int interface_to_busnum(struct usb_interface *interface)
+{
+ struct usb_device *udev = interface_to_usbdev(interface);
+ return udev->bus->busnum;
+}
+
+static inline int interface_to_devnum(struct usb_interface *interface)
+{
+ struct usb_device *udev = interface_to_usbdev(interface);
+ return udev->devnum;
+}
+
+static inline int interface_to_infnum(struct usb_interface *interface)
+{
+ return interface->cur_altsetting->desc.bInterfaceNumber;
+}
+
#endif /* __USBIP_COMMON_H */
--
1.7.5.1