From 10e232c597ac757e7f8600649f7e872e86de190f Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 28 Jun 2013 09:38:12 +0800 Subject: USB: check sg buffer size in usb_submit_urb USB spec stats that short packet can only appear at the end of transfer. Because lost of HC(EHCI/UHCI/OHCI/...) can't build a full packet from discontinuous buffers, we introduce the limit in usb_submit_urb() to avoid such kind of bad sg buffers coming from driver. The limit might be a bit strict: - platform has iommu to do sg list mapping - some host controllers may support to build full packet from discontinuous buffers. But considered that most of HCs don't support that, and driver need work well or keep consistent on different HCs and ARCHs, we have to introduce the limit. Currently, only usbtest is reported to pass such sg buffers to HC, and other users(mass storage, usbfs) don't have the problem. We don't check it on USB wireless device, because: - wireless devices can't be attached to common USB bus(EHCI/UHCI/OHCI/...) - the max packet size of endpoint may be odd, and often can't devide 4KB which is a typical usage in usb mass storage application Reported-by: Konstantin Filatov Reported-by: Denis V. Lunev Cc: Felipe Balbi Acked-by: Alan Stern Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/urb.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/usb/core/urb.c') diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index 16927fa88fb..e75115a04a2 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -7,6 +7,7 @@ #include #include #include +#include #define to_urb(d) container_of(d, struct urb, kref) @@ -413,6 +414,13 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags) urb->iso_frame_desc[n].status = -EXDEV; urb->iso_frame_desc[n].actual_length = 0; } + } else if (dev->speed != USB_SPEED_WIRELESS && urb->num_sgs) { + struct scatterlist *sg; + int i; + + for_each_sg(urb->sg, sg, urb->num_sgs - 1, i) + if (sg->length % max) + return -EINVAL; } /* the I/O buffer must be mapped/unmapped, except when length=0 */ -- cgit v1.2.3-70-g09d2 From 626f090c5cbbe557379978c7a9525011ad7fbbf6 Mon Sep 17 00:00:00 2001 From: Yacine Belkadi Date: Fri, 2 Aug 2013 20:10:04 +0200 Subject: usb: fix some scripts/kernel-doc warnings When building the htmldocs (in verbose mode), scripts/kernel-doc reports the following type of warnings: Warning(drivers/usb/core/usb.c:76): No description found for return value of 'usb_find_alt_setting' Fix them by: - adding some missing descriptions of return values - using "Return" sections for those descriptions Signed-off-by: Yacine Belkadi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/buffer.c | 5 ++-- drivers/usb/core/driver.c | 22 +++++++++++++++-- drivers/usb/core/file.c | 2 +- drivers/usb/core/hcd-pci.c | 2 ++ drivers/usb/core/hcd.c | 37 ++++++++++++++++++++-------- drivers/usb/core/hub.c | 37 +++++++++++++++++++--------- drivers/usb/core/message.c | 49 ++++++++++++++++++++----------------- drivers/usb/core/urb.c | 34 ++++++++++++++++---------- drivers/usb/core/usb.c | 60 ++++++++++++++++++++++++++++------------------ include/linux/usb.h | 12 ++++++---- 10 files changed, 173 insertions(+), 87 deletions(-) (limited to 'drivers/usb/core/urb.c') diff --git a/drivers/usb/core/buffer.c b/drivers/usb/core/buffer.c index b0585e623ba..23559746be9 100644 --- a/drivers/usb/core/buffer.c +++ b/drivers/usb/core/buffer.c @@ -43,10 +43,11 @@ static const size_t pool_max[HCD_BUFFER_POOLS] = { * * Call this as part of initializing a host controller that uses the dma * memory allocators. It initializes some pools of dma-coherent memory that - * will be shared by all drivers using that controller, or returns a negative - * errno value on error. + * will be shared by all drivers using that controller. * * Call hcd_buffer_destroy() to clean up after using those pools. + * + * Return: 0 if successful. A negative errno value otherwise. */ int hcd_buffer_create(struct usb_hcd *hcd) { diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 7609ac4aed1..124bcc50b0b 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -117,6 +117,8 @@ static DRIVER_ATTR(new_id, S_IRUGO | S_IWUSR, show_dynids, store_new_id); * @count: input size * * Removes a dynamic usb device ID from this driver. + * + * Return: @count on success. A negative error code otherwise. */ static ssize_t store_remove_id(struct device_driver *driver, const char *buf, size_t count) @@ -457,6 +459,8 @@ static int usb_unbind_interface(struct device *dev) * Callers must own the device lock, so driver probe() entries don't need * extra locking, but other call contexts may need to explicitly claim that * lock. + * + * Return: 0 on success. */ int usb_driver_claim_interface(struct usb_driver *driver, struct usb_interface *iface, void *priv) @@ -658,6 +662,8 @@ EXPORT_SYMBOL_GPL(usb_match_one_id); * These device tables are exported with MODULE_DEVICE_TABLE, through * modutils, to support the driver loading functionality of USB hotplugging. * + * Return: The first matching usb_device_id, or %NULL. + * * What Matches: * * The "match_flags" element in a usb_device_id controls which @@ -823,7 +829,8 @@ static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) * Registers a USB device driver with the USB core. The list of * unattached devices will be rescanned whenever a new driver is * added, allowing the new driver to attach to any recognized devices. - * Returns a negative error code on failure and 0 on success. + * + * Return: A negative error code on failure and 0 on success. */ int usb_register_device_driver(struct usb_device_driver *new_udriver, struct module *owner) @@ -879,7 +886,8 @@ EXPORT_SYMBOL_GPL(usb_deregister_device_driver); * Registers a USB interface driver with the USB core. The list of * unattached interfaces will be rescanned whenever a new driver is * added, allowing the new driver to attach to any recognized interfaces. - * Returns a negative error code on failure and 0 on success. + * + * Return: A negative error code on failure and 0 on success. * * NOTE: if you want your driver to use the USB major number, you must call * usb_register_dev() to enable that functionality. This function no longer @@ -1213,6 +1221,8 @@ done: * unpredictable times. * * This routine can run only in process context. + * + * Return: 0 if the suspend succeeded. */ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) { @@ -1294,6 +1304,8 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) * unpredictable times. * * This routine can run only in process context. + * + * Return: 0 on success. */ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) { @@ -1491,6 +1503,8 @@ void usb_autosuspend_device(struct usb_device *udev) * The caller must hold @udev's device lock. * * This routine can run only in process context. + * + * Return: 0 on success. A negative error code otherwise. */ int usb_autoresume_device(struct usb_device *udev) { @@ -1600,6 +1614,8 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend); * However if the autoresume fails then the counter is re-decremented. * * This routine can run only in process context. + * + * Return: 0 on success. */ int usb_autopm_get_interface(struct usb_interface *intf) { @@ -1633,6 +1649,8 @@ EXPORT_SYMBOL_GPL(usb_autopm_get_interface); * resumed. * * This routine can run in atomic context. + * + * Return: 0 on success. A negative error code otherwise. */ int usb_autopm_get_interface_async(struct usb_interface *intf) { diff --git a/drivers/usb/core/file.c b/drivers/usb/core/file.c index 6a4c40766f0..7421888087a 100644 --- a/drivers/usb/core/file.c +++ b/drivers/usb/core/file.c @@ -153,7 +153,7 @@ void usb_major_cleanup(void) * usb_deregister_dev() must be called when the driver is done with * the minor numbers given out by this function. * - * Returns -EINVAL if something bad happens with trying to register a + * Return: -EINVAL if something bad happens with trying to register a * device, and 0 on success. */ int usb_register_dev(struct usb_interface *intf, diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c index caeb8d6d39f..b9d3c43e385 100644 --- a/drivers/usb/core/hcd-pci.c +++ b/drivers/usb/core/hcd-pci.c @@ -171,6 +171,8 @@ static void ehci_wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd, * through the hotplug entry's driver_data. * * Store this function in the HCD's struct pci_driver as probe(). + * + * Return: 0 if successful. */ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) { diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 014dc996b4f..dc1346fee76 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -378,9 +378,10 @@ MODULE_PARM_DESC(authorized_default, * @buf: Buffer for USB string descriptor (header + UTF-16LE) * @len: Length (in bytes; may be odd) of descriptor buffer. * - * The return value is the number of bytes filled in: 2 + 2*strlen(s) or - * buflen, whichever is less. + * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len, + * whichever is less. * + * Note: * USB String descriptors can contain at most 126 characters; input * strings longer than that are truncated. */ @@ -416,7 +417,8 @@ ascii2desc(char const *s, u8 *buf, unsigned len) * * Produces either a manufacturer, product or serial number string for the * virtual root hub device. - * Returns the number of bytes filled in: the length of the descriptor or + * + * Return: The number of bytes filled in: the length of the descriptor or * of the provided buffer, whichever is less. */ static unsigned @@ -938,6 +940,8 @@ static void usb_bus_init (struct usb_bus *bus) * * Assigns a bus number, and links the controller into usbcore data * structures so that it can be seen by scanning the bus list. + * + * Return: 0 if successful. A negative error code otherwise. */ static int usb_register_bus(struct usb_bus *bus) { @@ -1002,6 +1006,8 @@ static void usb_deregister_bus (struct usb_bus *bus) * the device properly in the device tree and then calls usb_new_device() * to register the usb device. It also assigns the root hub's USB address * (always 1). + * + * Return: 0 if successful. A negative error code otherwise. */ static int register_root_hub(struct usb_hcd *hcd) { @@ -1108,7 +1114,9 @@ EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume); * @isoc: true for isochronous transactions, false for interrupt ones * @bytecount: how many bytes in the transaction. * - * Returns approximate bus time in nanoseconds for a periodic transaction. + * Return: Approximate bus time in nanoseconds for a periodic transaction. + * + * Note: * See USB 2.0 spec section 5.11.3; only periodic transfers need to be * scheduled in software, this function is only used for such scheduling. */ @@ -1166,7 +1174,7 @@ EXPORT_SYMBOL_GPL(usb_calc_bus_time); * be disabled. The actions carried out here are required for URB * submission, as well as for endpoint shutdown and for usb_kill_urb. * - * Returns 0 for no error, otherwise a negative error code (in which case + * Return: 0 for no error, otherwise a negative error code (in which case * the enqueue() method must fail). If no error occurs but enqueue() fails * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing * the private spinlock and returning. @@ -1221,7 +1229,7 @@ EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep); * be disabled. The actions carried out here are required for making * sure than an unlink is valid. * - * Returns 0 for no error, otherwise a negative error code (in which case + * Return: 0 for no error, otherwise a negative error code (in which case * the dequeue() method must fail). The possible error codes are: * * -EIDRM: @urb was not submitted or has already completed. @@ -1784,7 +1792,7 @@ rescan: * pass in the current alternate interface setting in cur_alt, * and pass in the new alternate interface setting in new_alt. * - * Returns an error if the requested bandwidth change exceeds the + * Return: An error if the requested bandwidth change exceeds the * bus bandwidth or host controller internal resources. */ int usb_hcd_alloc_bandwidth(struct usb_device *udev, @@ -1954,9 +1962,12 @@ void usb_hcd_reset_endpoint(struct usb_device *udev, * @num_streams: number of streams to allocate. * @mem_flags: flags hcd should use to allocate memory. * - * Sets up a group of bulk endpoints to have num_streams stream IDs available. + * Sets up a group of bulk endpoints to have @num_streams stream IDs available. * Drivers may queue multiple transfers to different stream IDs, which may * complete in a different order than they were queued. + * + * Return: On success, the number of allocated streams. On failure, a negative + * error code. */ int usb_alloc_streams(struct usb_interface *interface, struct usb_host_endpoint **eps, unsigned int num_eps, @@ -2201,6 +2212,8 @@ EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub); * khubd identifying and possibly configuring the device. * This is needed by OTG controller drivers, where it helps meet * HNP protocol timing requirements for starting a port reset. + * + * Return: 0 if successful. */ int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num) { @@ -2235,6 +2248,8 @@ EXPORT_SYMBOL_GPL(usb_bus_start_enum); * * If the controller isn't HALTed, calls the driver's irq handler. * Checks whether the controller is now dead. + * + * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise. */ irqreturn_t usb_hcd_irq (int irq, void *__hcd) { @@ -2320,7 +2335,8 @@ EXPORT_SYMBOL_GPL (usb_hc_died); * HC driver's private data. Initialize the generic members of the * hcd structure. * - * If memory is unavailable, returns NULL. + * Return: On success, a pointer to the created and initialized HCD structure. + * On failure (e.g. if memory is unavailable), %NULL. */ struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver, struct device *dev, const char *bus_name, @@ -2384,7 +2400,8 @@ EXPORT_SYMBOL_GPL(usb_create_shared_hcd); * HC driver's private data. Initialize the generic members of the * hcd structure. * - * If memory is unavailable, returns NULL. + * Return: On success, a pointer to the created and initialized HCD + * structure. On failure (e.g. if memory is unavailable), %NULL. */ struct usb_hcd *usb_create_hcd(const struct hc_driver *driver, struct device *dev, const char *bus_name) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 0416f835cfe..5d6d28a76e0 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -734,6 +734,8 @@ static void hub_tt_work(struct work_struct *work) * * call this function to control port's power via setting or * clearing the port's PORT_POWER feature. + * + * Return: 0 if successful. A negative error code otherwise. */ int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub, int port1, bool set) @@ -762,6 +764,8 @@ int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub, * * It may not be possible for that hub to handle additional full (or low) * speed transactions until that state is fully cleared out. + * + * Return: 0 if successful. A negative error code otherwise. */ int usb_hub_clear_tt_buffer(struct urb *urb) { @@ -964,6 +968,8 @@ static void hub_port_logical_disconnect(struct usb_hub *hub, int port1) * see that the device has been disconnected. When the device is * physically unplugged and something is plugged in, the events will * be received and processed normally. + * + * Return: 0 if successful. A negative error code otherwise. */ int usb_remove_device(struct usb_device *udev) { @@ -2115,6 +2121,8 @@ static inline void announce_device(struct usb_device *udev) { } * @udev: newly addressed device (in ADDRESS state) * * Finish enumeration for On-The-Go devices + * + * Return: 0 if successful. A negative error code otherwise. */ static int usb_enumerate_device_otg(struct usb_device *udev) { @@ -2197,6 +2205,8 @@ fail: * If the device is WUSB and not authorized, we don't attempt to read * the string descriptors, as they will be errored out by the device * until it has been authorized. + * + * Return: 0 if successful. A negative error code otherwise. */ static int usb_enumerate_device(struct usb_device *udev) { @@ -2277,13 +2287,14 @@ static void set_usb_port_removable(struct usb_device *udev) * udev has already been installed, but udev is not yet visible through * sysfs or other filesystem code. * - * It will return if the device is configured properly or not. Zero if - * the interface was registered with the driver core; else a negative - * errno value. - * * This call is synchronous, and may not be used in an interrupt context. * * Only the hub driver or root-hub registrar should ever call this. + * + * Return: Whether the device is configured properly or not. Zero if the + * interface was registered with the driver core; else a negative errno + * value. + * */ int usb_new_device(struct usb_device *udev) { @@ -2391,6 +2402,8 @@ fail: * * We share a lock (that we have) with device_del(), so we need to * defer its call. + * + * Return: 0. */ int usb_deauthorize_device(struct usb_device *usb_dev) { @@ -5025,10 +5038,11 @@ static int descriptors_changed(struct usb_device *udev, * re-connected. All drivers will be unbound, and the device will be * re-enumerated and probed all over again. * - * Returns 0 if the reset succeeded, -ENODEV if the device has been + * Return: 0 if the reset succeeded, -ENODEV if the device has been * flagged for logical disconnection, or some other negative error code * if the reset wasn't even attempted. * + * Note: * The caller must own the device lock. For example, it's safe to use * this from a driver probe() routine after downloading new firmware. * For calls that might not occur during probe(), drivers should lock @@ -5184,8 +5198,9 @@ re_enumerate: * method), performs the port reset, and then lets the drivers know that * the reset is over (using their post_reset method). * - * Return value is the same as for usb_reset_and_verify_device(). + * Return: The same as for usb_reset_and_verify_device(). * + * Note: * The caller must own the device lock. For example, it's safe to use * this from a driver probe() routine after downloading new firmware. * For calls that might not occur during probe(), drivers should lock @@ -5323,7 +5338,7 @@ EXPORT_SYMBOL_GPL(usb_queue_reset_device); * USB drivers call this function to get hub's child device * pointer. * - * Return NULL if input param is invalid and + * Return: %NULL if input param is invalid and * child's usb_device pointer if non-NULL. */ struct usb_device *usb_hub_find_child(struct usb_device *hdev, @@ -5357,8 +5372,8 @@ void usb_set_hub_port_connect_type(struct usb_device *hdev, int port1, * @hdev: USB device belonging to the usb hub * @port1: port num of the port * - * Return connect type of the port and if input params are - * invalid, return USB_PORT_CONNECT_TYPE_UNKNOWN. + * Return: The connect type of the port if successful. Or + * USB_PORT_CONNECT_TYPE_UNKNOWN if input params are invalid. */ enum usb_port_connect_type usb_get_hub_port_connect_type(struct usb_device *hdev, int port1) @@ -5418,8 +5433,8 @@ void usb_hub_adjust_deviceremovable(struct usb_device *hdev, * @hdev: USB device belonging to the usb hub * @port1: port num of the port * - * Return port's acpi handle if successful, NULL if params are - * invaild. + * Return: Port's acpi handle if successful, %NULL if params are + * invalid. */ acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev, int port1) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 6549a975b0c..82927e1ed27 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -119,15 +119,15 @@ static int usb_internal_control_msg(struct usb_device *usb_dev, * This function sends a simple control message to a specified endpoint and * waits for the message to complete, or timeout. * - * If successful, it returns the number of bytes transferred, otherwise a - * negative error number. - * * Don't use this function from within an interrupt context, like a bottom half * handler. If you need an asynchronous message, or need to send a message * from within interrupt context, use usb_submit_urb(). * If a thread in your driver uses this call, make sure your disconnect() * method can wait for it to complete. Since you don't have a handle on the * URB used, you can't cancel the request. + * + * Return: If successful, the number of bytes transferred. Otherwise, a negative + * error number. */ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u8 requesttype, __u16 value, __u16 index, void *data, @@ -170,15 +170,16 @@ EXPORT_SYMBOL_GPL(usb_control_msg); * This function sends a simple interrupt message to a specified endpoint and * waits for the message to complete, or timeout. * - * If successful, it returns 0, otherwise a negative error number. The number - * of actual bytes transferred will be stored in the actual_length paramater. - * * Don't use this function from within an interrupt context, like a bottom half * handler. If you need an asynchronous message, or need to send a message * from within interrupt context, use usb_submit_urb() If a thread in your * driver uses this call, make sure your disconnect() method can wait for it to * complete. Since you don't have a handle on the URB used, you can't cancel * the request. + * + * Return: + * If successful, 0. Otherwise a negative error number. The number of actual + * bytes transferred will be stored in the @actual_length paramater. */ int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe, void *data, int len, int *actual_length, int timeout) @@ -203,9 +204,6 @@ EXPORT_SYMBOL_GPL(usb_interrupt_msg); * This function sends a simple bulk message to a specified endpoint * and waits for the message to complete, or timeout. * - * If successful, it returns 0, otherwise a negative error number. The number - * of actual bytes transferred will be stored in the actual_length paramater. - * * Don't use this function from within an interrupt context, like a bottom half * handler. If you need an asynchronous message, or need to send a message * from within interrupt context, use usb_submit_urb() If a thread in your @@ -217,6 +215,11 @@ EXPORT_SYMBOL_GPL(usb_interrupt_msg); * users are forced to abuse this routine by using it to submit URBs for * interrupt endpoints. We will take the liberty of creating an interrupt URB * (with the default interval) if the target is an interrupt endpoint. + * + * Return: + * If successful, 0. Otherwise a negative error number. The number of actual + * bytes transferred will be stored in the @actual_length paramater. + * */ int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe, void *data, int len, int *actual_length, int timeout) @@ -341,9 +344,9 @@ static void sg_complete(struct urb *urb) * send every byte identified in the list. * @mem_flags: SLAB_* flags affecting memory allocations in this call * - * Returns zero for success, else a negative errno value. This initializes a - * scatter/gather request, allocating resources such as I/O mappings and urb - * memory (except maybe memory used by USB controller drivers). + * This initializes a scatter/gather request, allocating resources such as + * I/O mappings and urb memory (except maybe memory used by USB controller + * drivers). * * The request must be issued using usb_sg_wait(), which waits for the I/O to * complete (or to be canceled) and then cleans up all resources allocated by @@ -351,6 +354,8 @@ static void sg_complete(struct urb *urb) * * The request may be canceled with usb_sg_cancel(), either before or after * usb_sg_wait() is called. + * + * Return: Zero for success, else a negative errno value. */ int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev, unsigned pipe, unsigned period, struct scatterlist *sg, @@ -623,7 +628,7 @@ EXPORT_SYMBOL_GPL(usb_sg_cancel); * * This call is synchronous, and may not be used in an interrupt context. * - * Returns the number of bytes received on success, or else the status code + * Return: The number of bytes received on success, or else the status code * returned by the underlying usb_control_msg() call. */ int usb_get_descriptor(struct usb_device *dev, unsigned char type, @@ -671,7 +676,7 @@ EXPORT_SYMBOL_GPL(usb_get_descriptor); * * This call is synchronous, and may not be used in an interrupt context. * - * Returns the number of bytes received on success, or else the status code + * Return: The number of bytes received on success, or else the status code * returned by the underlying usb_control_msg() call. */ static int usb_get_string(struct usb_device *dev, unsigned short langid, @@ -805,7 +810,7 @@ static int usb_get_langid(struct usb_device *dev, unsigned char *tbuf) * * This call is synchronous, and may not be used in an interrupt context. * - * Returns length of the string (>= 0) or usb_control_msg status (< 0). + * Return: length of the string (>= 0) or usb_control_msg status (< 0). */ int usb_string(struct usb_device *dev, int index, char *buf, size_t size) { @@ -853,8 +858,8 @@ EXPORT_SYMBOL_GPL(usb_string); * @udev: the device whose string descriptor is being read * @index: the descriptor index * - * Returns a pointer to a kmalloc'ed buffer containing the descriptor string, - * or NULL if the index is 0 or the string could not be read. + * Return: A pointer to a kmalloc'ed buffer containing the descriptor string, + * or %NULL if the index is 0 or the string could not be read. */ char *usb_cache_string(struct usb_device *udev, int index) { @@ -894,7 +899,7 @@ char *usb_cache_string(struct usb_device *udev, int index) * * This call is synchronous, and may not be used in an interrupt context. * - * Returns the number of bytes received on success, or else the status code + * Return: The number of bytes received on success, or else the status code * returned by the underlying usb_control_msg() call. */ int usb_get_device_descriptor(struct usb_device *dev, unsigned int size) @@ -980,7 +985,7 @@ EXPORT_SYMBOL_GPL(usb_get_status); * * This call is synchronous, and may not be used in an interrupt context. * - * Returns zero on success, or else the status code returned by the + * Return: Zero on success, or else the status code returned by the * underlying usb_control_msg() call. */ int usb_clear_halt(struct usb_device *dev, int pipe) @@ -1277,7 +1282,7 @@ void usb_enable_interface(struct usb_device *dev, * endpoints in that interface; all such urbs must first be completed * (perhaps forced by unlinking). * - * Returns zero on success, or else the status code returned by the + * Return: Zero on success, or else the status code returned by the * underlying usb_control_msg() call. */ int usb_set_interface(struct usb_device *dev, int interface, int alternate) @@ -1431,7 +1436,7 @@ EXPORT_SYMBOL_GPL(usb_set_interface); * * The caller must own the device lock. * - * Returns zero on success, else a negative error code. + * Return: Zero on success, else a negative error code. */ int usb_reset_configuration(struct usb_device *dev) { @@ -1973,7 +1978,7 @@ static void cancel_async_set_config(struct usb_device *udev) * routine gets around the normal restrictions by using a work thread to * submit the change-config request. * - * Returns 0 if the request was successfully queued, error code otherwise. + * Return: 0 if the request was successfully queued, error code otherwise. * The caller has no way to know whether the queued request will eventually * succeed. */ diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index e75115a04a2..4e7a311ff6d 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -55,12 +55,12 @@ EXPORT_SYMBOL_GPL(usb_init_urb); * Creates an urb for the USB driver to use, initializes a few internal * structures, incrementes the usage counter, and returns a pointer to it. * - * If no memory is available, NULL is returned. - * * If the driver want to use this urb for interrupt, control, or bulk * endpoints, pass '0' as the number of iso packets. * * The driver must call usb_free_urb() when it is finished with the urb. + * + * Return: A pointer to the new urb, or %NULL if no memory is available. */ struct urb *usb_alloc_urb(int iso_packets, gfp_t mem_flags) { @@ -103,7 +103,7 @@ EXPORT_SYMBOL_GPL(usb_free_urb); * host controller driver. This allows proper reference counting to happen * for urbs. * - * A pointer to the urb with the incremented reference counter is returned. + * Return: A pointer to the urb with the incremented reference counter. */ struct urb *usb_get_urb(struct urb *urb) { @@ -200,13 +200,12 @@ EXPORT_SYMBOL_GPL(usb_unanchor_urb); * the particular kind of transfer, although they will not initialize * any transfer flags. * - * Successful submissions return 0; otherwise this routine returns a - * negative error number. If the submission is successful, the complete() - * callback from the URB will be called exactly once, when the USB core and - * Host Controller Driver (HCD) are finished with the URB. When the completion - * function is called, control of the URB is returned to the device - * driver which issued the request. The completion handler may then - * immediately free or reuse that URB. + * If the submission is successful, the complete() callback from the URB + * will be called exactly once, when the USB core and Host Controller Driver + * (HCD) are finished with the URB. When the completion function is called, + * control of the URB is returned to the device driver which issued the + * request. The completion handler may then immediately free or reuse that + * URB. * * With few exceptions, USB device drivers should never access URB fields * provided by usbcore or the HCD until its complete() is called. @@ -241,6 +240,9 @@ EXPORT_SYMBOL_GPL(usb_unanchor_urb); * that are standardized in the USB 2.0 specification. For bulk * endpoints, a synchronous usb_bulk_msg() call is available. * + * Return: + * 0 on successful submissions. A negative error number otherwise. + * * Request Queuing: * * URBs may be submitted to endpoints before previous ones complete, to @@ -572,6 +574,9 @@ EXPORT_SYMBOL_GPL(usb_submit_urb); * particular, when a driver calls this routine, it must insure that the * completion handler cannot deallocate the URB. * + * Return: -EINPROGRESS on success. See description for other values on + * failure. + * * Unlinking and Endpoint Queues: * * [The behaviors and guarantees described below do not apply to virtual @@ -846,6 +851,8 @@ EXPORT_SYMBOL_GPL(usb_unlink_anchored_urbs); * * Call this is you want to be sure all an anchor's * URBs have finished + * + * Return: Non-zero if the anchor became unused. Zero on timeout. */ int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor, unsigned int timeout) @@ -859,8 +866,11 @@ EXPORT_SYMBOL_GPL(usb_wait_anchor_empty_timeout); * usb_get_from_anchor - get an anchor's oldest urb * @anchor: the anchor whose urb you want * - * this will take the oldest urb from an anchor, + * This will take the oldest urb from an anchor, * unanchor and return it + * + * Return: The oldest urb from @anchor, or %NULL if @anchor has no + * urbs associated with it. */ struct urb *usb_get_from_anchor(struct usb_anchor *anchor) { @@ -909,7 +919,7 @@ EXPORT_SYMBOL_GPL(usb_scuttle_anchored_urbs); * usb_anchor_empty - is an anchor empty * @anchor: the anchor you want to query * - * returns 1 if the anchor has no urbs associated with it + * Return: 1 if the anchor has no urbs associated with it. */ int usb_anchor_empty(struct usb_anchor *anchor) { diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 7dad603dde4..0a6ee2e70b2 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -68,6 +68,8 @@ MODULE_PARM_DESC(autosuspend, "default autosuspend delay"); * @alt_num: alternate interface setting number to search for. * * Search the configuration's interface cache for the given alt setting. + * + * Return: The alternate setting, if found. %NULL otherwise. */ struct usb_host_interface *usb_find_alt_setting( struct usb_host_config *config, @@ -103,8 +105,7 @@ EXPORT_SYMBOL_GPL(usb_find_alt_setting); * @ifnum: the desired interface * * This walks the device descriptor for the currently active configuration - * and returns a pointer to the interface with that particular interface - * number, or null. + * to find the interface object with the particular interface number. * * Note that configuration descriptors are not required to assign interface * numbers sequentially, so that it would be incorrect to assume that @@ -115,6 +116,9 @@ EXPORT_SYMBOL_GPL(usb_find_alt_setting); * * Don't call this function unless you are bound to one of the interfaces * on this device or you have locked the device! + * + * Return: A pointer to the interface that has @ifnum as interface number, + * if found. %NULL otherwise. */ struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev, unsigned ifnum) @@ -139,8 +143,7 @@ EXPORT_SYMBOL_GPL(usb_ifnum_to_if); * @altnum: the desired alternate setting number * * This searches the altsetting array of the specified interface for - * an entry with the correct bAlternateSetting value and returns a pointer - * to that entry, or null. + * an entry with the correct bAlternateSetting value. * * Note that altsettings need not be stored sequentially by number, so * it would be incorrect to assume that the first altsetting entry in @@ -149,6 +152,9 @@ EXPORT_SYMBOL_GPL(usb_ifnum_to_if); * * Don't call this function unless you are bound to the intf interface * or you have locked the device! + * + * Return: A pointer to the entry of the altsetting array of @intf that + * has @altnum as the alternate setting number. %NULL if not found. */ struct usb_host_interface *usb_altnum_to_altsetting( const struct usb_interface *intf, @@ -191,6 +197,8 @@ static int __find_interface(struct device *dev, void *data) * This walks the bus device list and returns a pointer to the interface * with the matching minor and driver. Note, this only works for devices * that share the USB major number. + * + * Return: A pointer to the interface with the matching major and @minor. */ struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor) { @@ -390,6 +398,9 @@ static unsigned usb_bus_is_wusb(struct usb_bus *bus) * controllers) should ever call this. * * This call may not be used in a non-sleeping context. + * + * Return: On success, a pointer to the allocated usb device. %NULL on + * failure. */ struct usb_device *usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1) @@ -501,7 +512,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, * their probe() methods, when they bind to an interface, and release * them by calling usb_put_dev(), in their disconnect() methods. * - * A pointer to the device with the incremented reference counter is returned. + * Return: A pointer to the device with the incremented reference counter. */ struct usb_device *usb_get_dev(struct usb_device *dev) { @@ -535,8 +546,7 @@ EXPORT_SYMBOL_GPL(usb_put_dev); * their probe() methods, when they bind to an interface, and release * them by calling usb_put_intf(), in their disconnect() methods. * - * A pointer to the interface with the incremented reference counter is - * returned. + * Return: A pointer to the interface with the incremented reference counter. */ struct usb_interface *usb_get_intf(struct usb_interface *intf) { @@ -589,7 +599,7 @@ EXPORT_SYMBOL_GPL(usb_put_intf); * disconnect; in some drivers (such as usb-storage) the disconnect() * or suspend() method will block waiting for a device reset to complete. * - * Returns a negative error code for failure, otherwise 0. + * Return: A negative error code for failure, otherwise 0. */ int usb_lock_device_for_reset(struct usb_device *udev, const struct usb_interface *iface) @@ -628,14 +638,15 @@ EXPORT_SYMBOL_GPL(usb_lock_device_for_reset); * usb_get_current_frame_number - return current bus frame number * @dev: the device whose bus is being queried * - * Returns the current frame number for the USB host controller - * used with the given USB device. This can be used when scheduling + * Return: The current frame number for the USB host controller used + * with the given USB device. This can be used when scheduling * isochronous requests. * - * Note that different kinds of host controller have different - * "scheduling horizons". While one type might support scheduling only - * 32 frames into the future, others could support scheduling up to - * 1024 frames into the future. + * Note: Different kinds of host controller have different "scheduling + * horizons". While one type might support scheduling only 32 frames + * into the future, others could support scheduling up to 1024 frames + * into the future. + * */ int usb_get_current_frame_number(struct usb_device *dev) { @@ -685,11 +696,12 @@ EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor); * @mem_flags: affect whether allocation may block * @dma: used to return DMA address of buffer * - * Return value is either null (indicating no buffer could be allocated), or - * the cpu-space pointer to a buffer that may be used to perform DMA to the + * Return: Either null (indicating no buffer could be allocated), or the + * cpu-space pointer to a buffer that may be used to perform DMA to the * specified device. Such cpu-space buffers are returned along with the DMA * address (through the pointer provided). * + * Note: * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU * hardware during URB completion/resubmit. The implementation varies between @@ -735,17 +747,18 @@ EXPORT_SYMBOL_GPL(usb_free_coherent); * usb_buffer_map - create DMA mapping(s) for an urb * @urb: urb whose transfer_buffer/setup_packet will be mapped * - * Return value is either null (indicating no buffer could be mapped), or - * the parameter. URB_NO_TRANSFER_DMA_MAP is - * added to urb->transfer_flags if the operation succeeds. If the device - * is connected to this system through a non-DMA controller, this operation - * always succeeds. + * URB_NO_TRANSFER_DMA_MAP is added to urb->transfer_flags if the operation + * succeeds. If the device is connected to this system through a non-DMA + * controller, this operation always succeeds. * * This call would normally be used for an urb which is reused, perhaps * as the target of a large periodic transfer, with usb_buffer_dmasync() * calls to synchronize memory and dma state. * * Reverse the effect of this call with usb_buffer_unmap(). + * + * Return: Either %NULL (indicating no buffer could be mapped), or @urb. + * */ #if 0 struct urb *usb_buffer_map(struct urb *urb) @@ -850,9 +863,10 @@ EXPORT_SYMBOL_GPL(usb_buffer_unmap); * @sg: the scatterlist to map * @nents: the number of entries in the scatterlist * - * Return value is either < 0 (indicating no buffers could be mapped), or - * the number of DMA mapping array entries in the scatterlist. + * Return: Either < 0 (indicating no buffers could be mapped), or the + * number of DMA mapping array entries in the scatterlist. * + * Note: * The caller is responsible for placing the resulting DMA addresses from * the scatterlist into URB transfer buffer pointers, and for setting the * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs. diff --git a/include/linux/usb.h b/include/linux/usb.h index 6efdab08901..acb1b0aa77d 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -708,7 +708,10 @@ extern int usb_driver_claim_interface(struct usb_driver *driver, * usb_interface_claimed - returns true iff an interface is claimed * @iface: the interface being checked * - * Returns true (nonzero) iff the interface is claimed, else false (zero). + * Return: %true (nonzero) iff the interface is claimed, else %false + * (zero). + * + * Note: * Callers must own the driver model's usb bus readlock. So driver * probe() entries don't need extra locking, but other call contexts * may need to explicitly claim that lock. @@ -745,8 +748,9 @@ extern struct usb_host_interface *usb_find_alt_setting( * @buf: where to put the string * @size: how big is "buf"? * - * Returns length of the string (> 0) or negative if size was too small. + * Return: Length of the string (> 0) or negative if size was too small. * + * Note: * This identifier is intended to be "stable", reflecting physical paths in * hardware such as physical bus addresses for host controllers or ports on * USB hubs. That makes it stay the same until systems are physically @@ -1578,7 +1582,7 @@ extern int usb_anchor_empty(struct usb_anchor *anchor); * usb_urb_dir_in - check if an URB describes an IN transfer * @urb: URB to be checked * - * Returns 1 if @urb describes an IN transfer (device-to-host), + * Return: 1 if @urb describes an IN transfer (device-to-host), * otherwise 0. */ static inline int usb_urb_dir_in(struct urb *urb) @@ -1590,7 +1594,7 @@ static inline int usb_urb_dir_in(struct urb *urb) * usb_urb_dir_out - check if an URB describes an OUT transfer * @urb: URB to be checked * - * Returns 1 if @urb describes an OUT transfer (host-to-device), + * Return: 1 if @urb describes an OUT transfer (host-to-device), * otherwise 0. */ static inline int usb_urb_dir_out(struct urb *urb) -- cgit v1.2.3-70-g09d2 From bcc48f1a7a0d40ae2e5a26aff72c2b674fd8b596 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 8 Aug 2013 21:48:22 +0800 Subject: USB: introduce usb_device_no_sg_constraint() helper Some host controllers(such as xHCI) can support building packet from discontinuous buffers, so introduce one flag and helper for this kind of host controllers, then the feature can help some applications(such as usbnet) by supporting arbitrary length of sg buffers. Acked-by: Alan Stern Signed-off-by: Ming Lei Reviewed-by: Eric Dumazet Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/urb.c | 3 ++- include/linux/usb.h | 8 +++++++- 2 files changed, 9 insertions(+), 2 deletions(-) (limited to 'drivers/usb/core/urb.c') diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index 4e7a311ff6d..c12bc790a6a 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -416,7 +416,8 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags) urb->iso_frame_desc[n].status = -EXDEV; urb->iso_frame_desc[n].actual_length = 0; } - } else if (dev->speed != USB_SPEED_WIRELESS && urb->num_sgs) { + } else if (urb->num_sgs && !urb->dev->bus->no_sg_constraint && + dev->speed != USB_SPEED_WIRELESS) { struct scatterlist *sg; int i; diff --git a/include/linux/usb.h b/include/linux/usb.h index acb1b0aa77d..001629cd1a9 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -337,6 +337,7 @@ struct usb_bus { * the ep queue on a short transfer * with the URB_SHORT_NOT_OK flag set. */ + unsigned no_sg_constraint:1; /* no sg constraint */ unsigned sg_tablesize; /* 0 or largest number of sg list entries */ int devnum_next; /* Next open device number in @@ -684,6 +685,11 @@ static inline bool usb_device_supports_ltm(struct usb_device *udev) return udev->bos->ss_cap->bmAttributes & USB_LTM_SUPPORT; } +static inline bool usb_device_no_sg_constraint(struct usb_device *udev) +{ + return udev && udev->bus && udev->bus->no_sg_constraint; +} + /*-------------------------------------------------------------------------*/ @@ -1253,7 +1259,7 @@ typedef void (*usb_complete_t)(struct urb *); * transfer_buffer. * @sg: scatter gather buffer list, the buffer size of each element in * the list (except the last) must be divisible by the endpoint's - * max packet size + * max packet size if no_sg_constraint isn't set in 'struct usb_bus' * @num_mapped_sgs: (internal) number of mapped sg entries * @num_sgs: number of entries in the sg list * @transfer_buffer_length: How big is transfer_buffer. The transfer may -- cgit v1.2.3-70-g09d2