1CACHEFLUSH(2) Linux Programmer's Manual CACHEFLUSH(2)
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6 cacheflush - flush contents of instruction and/or data cache
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9 #include <asm/cachectl.h>
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11 int cacheflush(char *addr, int nbytes, int cache);
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14 cacheflush() flushes the contents of the indicated cache(s) for the
15 user addresses in the range addr to (addr+nbytes-1). cache may be one
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18 ICACHE Flush the instruction cache.
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20 DCACHE Write back to memory and invalidate the affected valid cache
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23 BCACHE Same as (ICACHE|DCACHE).
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26 cacheflush() returns 0 on success or -1 on error. If errors are
27 detected, errno will indicate the error.
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30 EFAULT Some or all of the address range addr to (addr+nbytes-1) is not
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33 EINVAL cache is not one of ICACHE, DCACHE, or BCACHE (but see BUGS).
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36 Historically, this system call was available on all MIPS UNIX variants
37 including RISC/os, IRIX, Ultrix, NetBSD, OpenBSD, and FreeBSD (and also
38 on some non-UNIX MIPS operating systems), so that the existence of this
39 call in MIPS operating systems is a de-facto standard.
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41 Caveat
42 cacheflush() should not be used in programs intended to be portable.
43 On Linux, this call first appeared on the MIPS architecture, but nowa‐
44 days, Linux provides a cacheflush() system call on some other architec‐
45 tures, but with different arguments.
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48 Linux kernels older than version 2.6.11 ignore the addr and nbytes
49 arguments, making this function fairly expensive. Therefore, the whole
50 cache is always flushed.
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52 This function always behaves as if BCACHE has been passed for the cache
53 argument and does not do any error checking on the cache argument.
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56 This page is part of release 5.04 of the Linux man-pages project. A
57 description of the project, information about reporting bugs, and the
58 latest version of this page, can be found at
59 https://www.kernel.org/doc/man-pages/.
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63Linux 2017-09-15 CACHEFLUSH(2)