52 lines
1.5 KiB
C
52 lines
1.5 KiB
C
/*
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* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms 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,
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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 the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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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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xfs_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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