/***
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*
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* stack/iovec.c
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*
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* RTnet - real-time networking subsystem
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* Copyright (C) 1999,2000 Zentropic Computing, LLC
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* 2002 Ulrich Marx <marx@kammer.uni-hannover.de>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/string.h>
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#include <rtdm/driver.h>
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#include <rtnet_iovec.h>
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#include <rtnet_socket.h>
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ssize_t rtnet_write_to_iov(struct rtdm_fd *fd, struct iovec *iov, int iovlen,
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const void *data, size_t len)
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{
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ssize_t ret = 0;
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size_t nbytes;
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int n;
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for (n = 0; len > 0 && n < iovlen; n++, iov++) {
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if (iov->iov_len == 0)
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continue;
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nbytes = iov->iov_len;
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if (nbytes > len)
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nbytes = len;
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ret = rtnet_put_arg(fd, iov->iov_base, data, nbytes);
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if (ret)
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break;
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len -= nbytes;
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data += nbytes;
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iov->iov_len -= nbytes;
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iov->iov_base += nbytes;
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ret += nbytes;
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if (ret < 0) {
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ret = -EINVAL;
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break;
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}
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(rtnet_write_to_iov);
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ssize_t rtnet_read_from_iov(struct rtdm_fd *fd, struct iovec *iov, int iovlen,
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void *data, size_t len)
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{
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ssize_t ret = 0;
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size_t nbytes;
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int n;
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for (n = 0; len > 0 && n < iovlen; n++, iov++) {
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if (iov->iov_len == 0)
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continue;
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nbytes = iov->iov_len;
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if (nbytes > len)
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nbytes = len;
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if (!rtdm_fd_is_user(fd))
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memcpy(data, iov->iov_base, nbytes);
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else {
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ret = rtdm_copy_from_user(fd, data, iov->iov_base,
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nbytes);
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if (ret)
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break;
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}
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len -= nbytes;
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data += nbytes;
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iov->iov_len -= nbytes;
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iov->iov_base += nbytes;
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ret += nbytes;
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if (ret < 0) {
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ret = -EINVAL;
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break;
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}
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(rtnet_read_from_iov);
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