The note regarding PROT_SEM is done based on observation that it is not actually used in mprotect code (as far as i understood it). --- man2/mprotect.2 | 58 +++++++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 50 insertions(+), 8 deletions(-) diff --git a/man2/mprotect.2 b/man2/mprotect.2 index 440fa65..4c3a1e2 100644 --- a/man2/mprotect.2 +++ b/man2/mprotect.2 @@ -30,12 +30,6 @@ .\" 2007-06-02, mtk: Fairly substantial rewrites and additions, and .\" a much improved example program. .\" -.\" FIXME The following protection flags need documenting: -.\" PROT_SEM -.\" PROT_GROWSDOWN -.\" PROT_GROWSUP -.\" PROT_SAO (PowerPC) -.\" .TH MPROTECT 2 2015-07-23 "Linux" "Linux Programmer's Manual" .SH NAME mprotect, pkey_mprotect \- set protection on a region of memory @@ -60,7 +54,7 @@ that violates the protection, then the kernel generates a signal for the process. .PP .I prot -is either +is a combination of the following access flags: .B PROT_NONE or a bitwise-or of the other values in the following list: .TP 1.1i @@ -75,6 +69,38 @@ The memory can be modified. .TP .B PROT_EXEC The memory can be executed. +'\" 882ad449046cec136c484dd2b3659fb4c683e0a3 +.TP +.BR PROT_SEM " (since Linux 2.5.7)" +The memory can be used for atomic operations. It was introduced as part of +.BR futex (2) +implementation (in order), but not actually used in any currently supported +architecture so far. +'\" aba46c5027cb59d98052231b36efcbbde9c77a1d ef3d3246a0d06be622867d21af25f997aeeb105f +.TP +.BR PROT_SAO " (since Linux 2.6.26)" +The memory should have strong access ordering. This feature is specific to +PowerPC architecture (version 2.06 of architecture specification adds SAO CPU +feature, and is available on POWER 7 and newer, for example). +.PP +'\" c1dd59582e5b518983b0f4db66f0f8a969139c1b +Additionally (since Linux 2.6.0), +.I prot +can have one of the following flags set: +.TP 1.1i +.B PROT_GROWSUP +Apply protection mode to the whole VMA, which grows up (it should be mapped with +.B MAP_GROWSUP +flag set, which itself is available on IA-64 only, or be stack segment on +HP PARISC). +.TP +.B PROT_GROWSDOWN +Apply protection mode to the whole VMA, which grows down (it should be mapped +with +.B MAP_GROWSDOWN +flag set). +.PP +This is especially useful for stacks and other mappings which can grow. .PP Like .BR mprotect (), @@ -122,7 +148,23 @@ or not a multiple of the system page size. .RB ( pkey_mprotect ()) \fIpkey\fP has not been allocated with .BR pkey_alloc (2) -.\" Or: both PROT_GROWSUP and PROT_GROWSDOWN were specified in 'prot'. +.TP +.BR EINVAL +Both +.BR PROT_GROWSUP " and " PROT_GROWSDOWN +were specified in +.IR prot . +.TP +.BR EINVAL +Invalid flags specified in +.IR prot . +.TP +.BR EINVAL +(PowerPC architecture) +.B PROT_SAO +specified in +.IR prot , +but SAO hardware feature is no available. .TP .B ENOMEM Internal kernel structures could not be allocated. -- 2.10.2 -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
