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/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <xfs.h>
/* Read from kernel buffer at src to user/kernel buffer defined
* by the uio structure. Advance the pointer in the uio struct
* as we go.
*/
int
uio_read(caddr_t src, size_t len, struct uio *uio)
{
size_t count;
if (!len || !uio->uio_resid)
return 0;
count = uio->uio_iov->iov_len;
if (!count)
return 0;
if (count > len)
count = len;
if (uio->uio_segflg == UIO_USERSPACE) {
if (copy_to_user(uio->uio_iov->iov_base, src, count))
return EFAULT;
} else {
ASSERT(uio->uio_segflg == UIO_SYSSPACE);
memcpy(uio->uio_iov->iov_base, src, count);
}
uio->uio_iov->iov_base = (void*)((char*)uio->uio_iov->iov_base + count);
uio->uio_iov->iov_len -= count;
uio->uio_offset += count;
uio->uio_resid -= count;
return 0;
}
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