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diff --git a/static/freebsd/man9/pmap_enter.9 b/static/freebsd/man9/pmap_enter.9 new file mode 100644 index 00000000..d4b8dd7e --- /dev/null +++ b/static/freebsd/man9/pmap_enter.9 @@ -0,0 +1,170 @@ +.\" +.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org> +.\" Copyright (c) 2014 The FreeBSD Foundation +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.Dd December 16, 2018 +.Dt PMAP_ENTER 9 +.Os +.Sh NAME +.Nm pmap_enter +.Nd insert a virtual page into a physical map +.Sh SYNOPSIS +.In sys/param.h +.In vm/vm.h +.In vm/pmap.h +.Ft int +.Fo pmap_enter +.Fa "pmap_t pmap" "vm_offset_t va" "vm_page_t m" "vm_prot_t prot" +.Fa "u_int flags" "int8_t psind" +.Fc +.Sh DESCRIPTION +The +.Fn pmap_enter +function creates a mapping in the physical map +.Fa pmap +from the virtual address +.Fa va +to the physical page +.Fa m +with the protection +.Fa prot . +Any previous mapping at the virtual address +.Fa va +is destroyed. +.Pp +The +.Fa flags +argument may have the following values: +.Bl -tag -width ".Dv PMAP_ENTER_NOSLEEP" +.It Dv VM_PROT_READ +A read access to the given virtual address triggered the call. +.It Dv VM_PROT_WRITE +A write access to the given virtual address triggered the call. +.It Dv VM_PROT_EXECUTE +An execute access to the given virtual address triggered the call. +.It Dv PMAP_ENTER_WIRED +The mapping should be marked as wired. +.It Dv PMAP_ENTER_NOSLEEP +This function may not sleep during creation of the mapping. +If the mapping cannot be created without sleeping, an appropriate +Mach VM error is returned. +.El +If the +.Dv PMAP_ENTER_NOSLEEP +flag is not specified, this function must create the requested mapping +before returning. +It may not fail. +In order to create the requested mapping, this function may destroy +any non-wired mapping in any pmap. +.Pp +The +.Fa psind +parameter specifies the page size that should be used by the mapping. +The supported page sizes are described by the global array +.Dv pagesizes[] . +The desired page size is specified by passing the index of the array +element that equals the desired page size. +.Pp +When the +.Fn pmap_enter +function destroys or updates a managed mapping, including an existing +mapping at virtual address +.Fa va , +it updates the +.Ft vm_page +structure corresponding to the previously mapped physical page. +If the physical page was accessed through the managed mapping, +then the +.Ft vm_page +structure's +.Dv PGA_REFERENCED +aflag is set. +If the physical page was modified through the managed mapping, then the +.Fn vm_page_dirty +function is called on the +.Ft vm_page +structure. +.Pp +The +.Dv PGA_WRITEABLE +aflag must be set for the page +.Fa m +if the new mapping is managed and writeable. +It is advised to clear +.Dv PGA_WRITEABLE +for destroyed mappings if the implementation can ensure +that no other writeable managed mappings for the previously +mapped pages exist. +.Pp +If the request modifies an existing mapping to use a different physical +page, an implementation of +.Nm +must invalidate the previous mapping before installing the new one. +This ensures that all threads sharing the pmap keep a consistent +view of the mapping, which is necessary for the correct handling +of CoW (copy on write) faults. +.Pp +If the page +.Fa m +is managed, the page must be busied by the caller +or the owning object must be locked. +In the later case, the +.Dv PMAP_ENTER_NOSLEEP +must be specified by the caller. +.Pp +The +.Fn pmap_enter +function must handle the multiprocessor TLB consistency for the +given address. +.Sh NOTES +On arm and i386 architectures the existing implementation +of the +.Nm +function is incomplete, only value 0 for +.Fa psind +is supported. +Other supported architectures, except amd64, have +.Dv pagesizes[] +array of size 1. +.Sh RETURN VALUES +If successful, the +.Fn pmap_enter +function returns +.Er KERN_SUCCESS . +If the +.Dv PMAP_ENTER_NOSLEEP +flag was specified and the resources required for the mapping cannot +be acquired without sleeping, +.Dv KERN_RESOURCE_SHORTAGE +is returned. +.Sh SEE ALSO +.Xr pmap 9 +.Sh AUTHORS +This manual page was first written by +.An Bruce M Simpson Aq Mt bms@spc.org +and then rewritten by +.An Alan Cox Aq Mt alc@FreeBSD.org +and +.An Konstantin Belousov Aq Mt kib@FreeBSD.org . |