This commit is contained in:
Roland McGrath 1995-02-21 20:27:45 +00:00
parent 6e583a6e11
commit caa8cd20fd
2 changed files with 8 additions and 5 deletions

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@ -8,3 +8,5 @@ configparms
sun4 i386 i386-gnuelf hp300-netbsd hp300
ieeetest hppa-sysdeps regex
gpl2lgpl.sed

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@ -42,25 +42,26 @@ Cambridge, MA 02139, USA. */
#if PAGE_COPY_THRESHOLD
#include <assert.h>
#define PAGE_COPY_FWD_MAYBE(dstp, srcp, nbytes_left, nbytes) \
do \
{ \
if ((nbytes) >= PAGE_COPY_THRESHOLD && \
PAGE_OFFSET (dstp) == PAGE_OFFSET (srcp)) \
PAGE_OFFSET ((dstp) - (srcp)) == 0) \
{ \
/* The amount to copy is past the threshold for copying \
pages virtually with kernel VM operations, and the \
source and destination addresses have the same alignment. */ \
size_t nbytes_before = PAGE_OFFSET (PAGE_SIZE - PAGE_OFFSET (dstp));\
size_t nbytes_before = PAGE_OFFSET (-(dstp)); \
if (nbytes_before != 0) \
{ \
/* First copy the words before the first page boundary. */ \
WORD_COPY_FWD (dstp, srcp, nbytes_left, nbytes_before); \
nbytes_before -= nbytes_left; \
assert (nbytes_left == 0); \
nbytes -= nbytes_before; \
} \
if (nbytes_before == 0) \
PAGE_COPY_FWD (dstp, srcp, nbytes_left, nbytes); \
PAGE_COPY_FWD (dstp, srcp, nbytes_left, nbytes); \
} \
} while (0)