'\"macro stdmacro
.TH CACHEFLUSH 2
.SH NAME
cacheflush, _flush_cache \- flush contents of instruction and/or data cache
.SH SYNOPSIS
.B "#include <sys/cachectl.h>"
.sp
.B "int cacheflush (void \(**addr, int nbytes, int cache);"
.sp
.B "int _flush_cache (char \(**addr, int nbytes, int cache);"
.SH DESCRIPTION
\f2cacheflush\f1 and \f2_flush_cache\f1 are different names for the
same function. They flush the contents of the indicated cache(s) for user
addresses in the range \f2addr\f1 to (\f2addr\f1+\f2nbytes\f1-1).  The
.I cache
parameter may be one of:
.TP 17
.B ICACHE
Flush only the instruction cache
.TP
.B DCACHE
Flush only the data cache
.TP
.B BCACHE
Flush both the instruction and the data cache
.SH "RETURN VALUE"
.I cacheflush
and
.I _flush_cache
return 0 when no errors are detected.
If errors are detected, they
return \-1 with the error cause indicated in \f2errno\f1.
For IP19, IP21 and IP25, the following describes the action of this command 
on any physical lines corresponding to the input virtual address range that 
may be present in the caches.
On IP19 and IP25, DCACHE flushing writes back any dirty data and invalidates
the cache line in the data and the secondary cache. ICACHE flushing on the
IP19 and IP25 consists of invalidating the line in the icache and the 
secondary cache. Additionally, prior to this, if the line is dirty in the 
dcache and/or secondary, it is written back.
On IP21s, DCACHE flushing is a no op, and ICACHE flushing does not affect
the gcache directly, but loads in a set of different instructions into the
icache.
The BCACHE option in all cases writes back the lines if they are dirty, and
then invalidates them if they are present in any of the caches (except for
IP21s, where the lines are displaced from the icache).


.SH ERRORS
.TP 17
.SM [EINVAL]
The
.I cache
parameter is not one of ICACHE, DCACHE, or BCACHE.
.TP
.SM [EFAULT]
Some or all of the address range
.I addr
to (\f2addr\f1+\f2nbytes\f1-1) is not accessible.
.SH "SEE ALSO"
cachectl(2)