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subpage_prot.2: Use syscall(SYS_...); for system calls without a wrapper 

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
Alejandro Colomar 2021-06-12 10:31:26 +02:00 committed by Michael Kerrisk
parent c9f3f8494c
commit c237072776
1 changed files with 9 additions and 6 deletions
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15
man2/subpage_prot.2
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@ -32,12 +32,18 @@
subpage_prot \- define a subpage protection for an address range
.SH SYNOPSIS
.nf
.BI "int subpage_prot(unsigned long " addr ", unsigned long " len \
", uint32_t *" map );
.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */"
.B #include <unistd.h>
.PP
.BI "int syscall(SYS_subpage_prot, unsigned long " addr ", unsigned long " len ,
.BI " uint32_t *" map );
.fi
.PP
.IR Note :
There is no glibc wrapper for this system call; see NOTES.
glibc provides no wrapper for
.BR subpage_prot (),
necessitating the use of
.BR syscall (2).
.SH DESCRIPTION
The PowerPC-specific
.BR subpage_prot ()
@ -96,9 +102,6 @@ No library support is provided.
.SH CONFORMING TO
This system call is Linux-specific.
.SH NOTES
Glibc does not provide a wrapper for this system call; call it using
.BR syscall (2).
.PP
Normal page protections (at the 64-kB page level) also apply;
the subpage protection mechanism is an additional constraint,
so putting 0 in a 2-bit field won't allow writes to a page that is otherwise