From 4d5e18d9ed93fcdf1bd625aac80048f6cd0063bc Mon Sep 17 00:00:00 2001 From: Guido Kiener Date: Wed, 12 Sep 2018 10:51:01 +0200 Subject: usb: usbtmc: Optimize usbtmc_write Use new usbtmc_generic_write function to maximize bandwidth during long data transfer. The maximum output transfer size is limited to INT_MAX (=2GB). Signed-off-by: Guido Kiener Reviewed-by: Steve Bayless Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/usbtmc.c | 170 ++++++++++++++++++++++++++++----------------- 1 file changed, 106 insertions(+), 64 deletions(-) (limited to 'drivers/usb/class/usbtmc.c') diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 3ed2146fb670..c476b53b6237 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -1509,94 +1509,136 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf, { struct usbtmc_file_data *file_data; struct usbtmc_device_data *data; + struct urb *urb = NULL; + ssize_t retval = 0; u8 *buffer; - int retval; - int actual; - unsigned long int n_bytes; - int remaining; - int done; - int this_part; + u32 remaining, done; + u32 transfersize, aligned, buflen; file_data = filp->private_data; data = file_data->data; - buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); - if (!buffer) - return -ENOMEM; - mutex_lock(&data->io_mutex); + if (data->zombie) { retval = -ENODEV; goto exit; } - remaining = count; done = 0; - while (remaining > 0) { - if (remaining > USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE) { - this_part = USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE; - buffer[8] = 0; - } else { - this_part = remaining; - buffer[8] = file_data->eom_val; - } + spin_lock_irq(&file_data->err_lock); + file_data->out_transfer_size = 0; + file_data->out_status = 0; + spin_unlock_irq(&file_data->err_lock); - /* Setup IO buffer for DEV_DEP_MSG_OUT message */ - buffer[0] = 1; - buffer[1] = data->bTag; - buffer[2] = ~data->bTag; - buffer[3] = 0; /* Reserved */ - buffer[4] = this_part >> 0; - buffer[5] = this_part >> 8; - buffer[6] = this_part >> 16; - buffer[7] = this_part >> 24; - /* buffer[8] is set above... */ - buffer[9] = 0; /* Reserved */ - buffer[10] = 0; /* Reserved */ - buffer[11] = 0; /* Reserved */ - - if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf + done, this_part)) { - retval = -EFAULT; - goto exit; - } + if (!count) + goto exit; - n_bytes = roundup(USBTMC_HEADER_SIZE + this_part, 4); - memset(buffer + USBTMC_HEADER_SIZE + this_part, 0, n_bytes - (USBTMC_HEADER_SIZE + this_part)); + if (down_trylock(&file_data->limit_write_sem)) { + /* previous calls were async */ + retval = -EBUSY; + goto exit; + } - do { - retval = usb_bulk_msg(data->usb_dev, - usb_sndbulkpipe(data->usb_dev, - data->bulk_out), - buffer, n_bytes, - &actual, file_data->timeout); - if (retval != 0) - break; - n_bytes -= actual; - } while (n_bytes); - - data->bTag_last_write = data->bTag; + urb = usbtmc_create_urb(); + if (!urb) { + retval = -ENOMEM; + up(&file_data->limit_write_sem); + goto exit; + } + + buffer = urb->transfer_buffer; + buflen = urb->transfer_buffer_length; + + if (count > INT_MAX) { + transfersize = INT_MAX; + buffer[8] = 0; + } else { + transfersize = count; + buffer[8] = file_data->eom_val; + } + + /* Setup IO buffer for DEV_DEP_MSG_OUT message */ + buffer[0] = 1; + buffer[1] = data->bTag; + buffer[2] = ~data->bTag; + buffer[3] = 0; /* Reserved */ + buffer[4] = transfersize >> 0; + buffer[5] = transfersize >> 8; + buffer[6] = transfersize >> 16; + buffer[7] = transfersize >> 24; + /* buffer[8] is set above... */ + buffer[9] = 0; /* Reserved */ + buffer[10] = 0; /* Reserved */ + buffer[11] = 0; /* Reserved */ + + remaining = transfersize; + + if (transfersize + USBTMC_HEADER_SIZE > buflen) { + transfersize = buflen - USBTMC_HEADER_SIZE; + aligned = buflen; + } else { + aligned = (transfersize + (USBTMC_HEADER_SIZE + 3)) & ~3; + } + + if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf, transfersize)) { + retval = -EFAULT; + up(&file_data->limit_write_sem); + goto exit; + } + + dev_dbg(&data->intf->dev, "%s(size:%u align:%u)\n", __func__, + (unsigned int)transfersize, (unsigned int)aligned); + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, + 16, 1, buffer, aligned, true); + + usb_fill_bulk_urb(urb, data->usb_dev, + usb_sndbulkpipe(data->usb_dev, data->bulk_out), + urb->transfer_buffer, aligned, + usbtmc_write_bulk_cb, file_data); + + usb_anchor_urb(urb, &file_data->submitted); + retval = usb_submit_urb(urb, GFP_KERNEL); + if (unlikely(retval)) { + usb_unanchor_urb(urb); + up(&file_data->limit_write_sem); + goto exit; + } + + remaining -= transfersize; + + data->bTag_last_write = data->bTag; + data->bTag++; + + if (!data->bTag) data->bTag++; - if (!data->bTag) - data->bTag++; + /* call generic_write even when remaining = 0 */ + retval = usbtmc_generic_write(file_data, buf + transfersize, remaining, + &done, USBTMC_FLAG_APPEND); + /* truncate alignment bytes */ + if (done > remaining) + done = remaining; - if (retval < 0) { - dev_err(&data->intf->dev, - "Unable to send data, error %d\n", retval); - if (file_data->auto_abort) - usbtmc_ioctl_abort_bulk_out(data); - goto exit; - } + /*add size of first urb*/ + done += transfersize; - remaining -= this_part; - done += this_part; + if (retval < 0) { + usb_kill_anchored_urbs(&file_data->submitted); + + dev_err(&data->intf->dev, + "Unable to send data, error %d\n", (int)retval); + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_out(data); + goto exit; } - retval = count; + retval = done; exit: + usb_free_urb(urb); mutex_unlock(&data->io_mutex); - kfree(buffer); return retval; } -- cgit