67 строки
2.0 KiB
C
67 строки
2.0 KiB
C
/*
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* Copyright (c) 2000-2003 Silicon Graphics, Inc. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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*
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* Further, this software is distributed without any warranty that it is
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* free of the rightful claim of any third person regarding infringement
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* or the like. Any license provided herein, whether implied or
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* otherwise, applies only to this software file. Patent licenses, if
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* any, provided herein do not apply to combinations of this program with
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* other software, or any other product whatsoever.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write the Free Software Foundation, Inc., 59
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* Temple Place - Suite 330, Boston MA 02111-1307, USA.
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*
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* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
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* Mountain View, CA 94043, or:
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*
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* http://www.sgi.com
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*
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* For further information regarding this notice, see:
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*
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* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
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*/
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#include <xfs.h>
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/* Read from kernel buffer at src to user/kernel buffer defined
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* by the uio structure. Advance the pointer in the uio struct
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* as we go.
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*/
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int
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uio_read(caddr_t src, size_t len, struct uio *uio)
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{
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size_t count;
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if (!len || !uio->uio_resid)
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return 0;
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count = uio->uio_iov->iov_len;
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if (!count)
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return 0;
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if (count > len)
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count = len;
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if (uio->uio_segflg == UIO_USERSPACE) {
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if (copy_to_user(uio->uio_iov->iov_base, src, count))
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return EFAULT;
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} else {
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ASSERT(uio->uio_segflg == UIO_SYSSPACE);
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memcpy(uio->uio_iov->iov_base, src, count);
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}
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uio->uio_iov->iov_base = (void*)((char*)uio->uio_iov->iov_base + count);
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uio->uio_iov->iov_len -= count;
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uio->uio_offset += count;
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uio->uio_resid -= count;
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return 0;
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}
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