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diff --git a/static/openbsd/man9/uvm_map.9 b/static/openbsd/man9/uvm_map.9 new file mode 100644 index 00000000..6afa9f6f --- /dev/null +++ b/static/openbsd/man9/uvm_map.9 @@ -0,0 +1,331 @@ +.\" $OpenBSD: uvm_map.9,v 1.3 2022/12/09 21:19:53 jmc Exp $ +.\" $NetBSD: uvm.9,v 1.14 2000/06/29 06:08:44 mrg Exp $ +.\" +.\" Copyright (c) 1998 Matthew R. Green +.\" 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 ``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 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 $Mdocdate: December 9 2022 $ +.Dt UVM_MAP 9 +.Os +.Sh NAME +.Nm uvm_map , +.Nm uvm_map_pageable , +.Nm uvm_map_pageable_all , +.Nm uvm_map_checkprot , +.Nm uvm_map_protect , +.Nm uvmspace_alloc , +.Nm uvmspace_exec , +.Nm uvmspace_fork , +.Nm uvmspace_free , +.Nm uvmspace_share , +.Nm uvm_uarea_alloc , +.Nm uvm_uarea_free , +.Nm UVM_MAPFLAG +.Nd virtual address space management interface +.Sh SYNOPSIS +.In sys/param.h +.In uvm/uvm.h +.Ft int +.Fn uvm_map "vm_map_t map" "vaddr_t *startp" "vsize_t size" "struct uvm_object *uobj" "voff_t uoffset" "vsize_t alignment" "unsigned int flags" +.Ft int +.Fn uvm_map_pageable "vm_map_t map" "vaddr_t start" "vaddr_t end" "boolean_t new_pageable" "int lockflags" +.Ft int +.Fn uvm_map_pageable_all "vm_map_t map" "int flags" "vsize_t limit" +.Ft boolean_t +.Fn uvm_map_checkprot "vm_map_t map" "vaddr_t start" "vaddr_t end" "vm_prot_t protection" +.Ft int +.Fn uvm_map_protect "vm_map_t map" "vaddr_t start" "vaddr_t end" "vm_prot_t new_prot" "int et" "boolean_t set_max" "boolean_t checkimmutable" +.Ft struct vmspace * +.Fn uvmspace_alloc "vaddr_t min" "vaddr_t max" "boolean_t pageable" "boolean_t remove_holes" +.Ft void +.Fn uvmspace_exec "struct proc *p" "vaddr_t start" "vaddr_t end" +.Ft struct vmspace * +.Fn uvmspace_fork "struct process *pr" +.Ft void +.Fn uvmspace_free "struct vmspace *vm" +.Ft struct vmspace * +.Fn uvmspace_share "struct process *pr" +.Ft vaddr_t +.Fn uvm_uarea_alloc "void" +.Ft void +.Fn uvm_uarea_free "struct proc *p" +.Ft unsigned int +.Fn UVM_MAPFLAG "vm_prot_t prot" "vm_prot_t maxprot" "vm_inherit_t inh" "int advice" "int flags" +.Sh DESCRIPTION +The +.Fn uvm_map +function establishes a valid mapping in map +.Fa map , +which must be unlocked. +The new mapping has size +.Fa size , +which must be in +.Dv PAGE_SIZE +units. +If +.Fa alignment +is non-zero, it describes the required alignment of the list, in +power-of-two notation. +The +.Fa uobj +and +.Fa uoffset +arguments can have four meanings. +When +.Fa uobj +is +.Dv NULL +and +.Fa uoffset +is +.Dv UVM_UNKNOWN_OFFSET , +.Fn uvm_map +does not use the machine-dependent +.Dv PMAP_PREFER +function. +If +.Fa uoffset +is any other value, it is used as the hint to +.Dv PMAP_PREFER . +When +.Fa uobj +is not +.Dv NULL +and +.Fa uoffset +is +.Dv UVM_UNKNOWN_OFFSET , +.Fn uvm_map +finds the offset based upon the virtual address, passed as +.Fa startp . +If +.Fa uoffset +is any other value, we are doing a normal mapping at this offset. +The start address of the map will be returned in +.Fa startp . +.Pp +.Fa flags +passed to +.Fn uvm_map +are typically created using the +.Fn UVM_MAPFLAG +macro, which uses the following values. +The +.Fa prot +and +.Fa maxprot +can take a mix of the following values: +.Bd -literal +#define PROT_MASK 0x07 /* protection mask */ +#define PROT_NONE 0x00 /* protection none */ +#define PROT_READ 0x01 /* read */ +#define PROT_WRITE 0x02 /* write */ +#define PROT_EXEC 0x04 /* exec */ +.Ed +.Pp +The values that +.Fa inh +can take are: +.Bd -literal +#define MAP_INHERIT_MASK 0x30 /* inherit mask */ +#define MAP_INHERIT_SHARE 0x00 /* "share" */ +#define MAP_INHERIT_COPY 0x10 /* "copy" */ +#define MAP_INHERIT_NONE 0x20 /* "none" */ +#define MAP_INHERIT_ZERO 0x30 /* "zero" */ +.Ed +.Pp +The values that +.Fa advice +can take are: +.Bd -literal +#define MADV_NORMAL 0x0 /* 'normal' */ +#define MADV_RANDOM 0x1 /* 'random' */ +#define MADV_SEQUENTIAL 0x2 /* 'sequential' */ +#define MADV_MASK 0x7 /* mask */ +.Ed +.Pp +The values that +.Fa flags +can take are: +.Bd -literal +#define UVM_FLAG_FIXED 0x0010000 /* find space */ +#define UVM_FLAG_OVERLAY 0x0020000 /* establish overlay */ +#define UVM_FLAG_NOMERGE 0x0040000 /* don't merge map entries */ +#define UVM_FLAG_COPYONW 0x0080000 /* set copy_on_write flag */ +#define UVM_FLAG_TRYLOCK 0x0100000 /* fail if we can not lock map */ +#define UVM_FLAG_HOLE 0x0200000 /* no backend */ +#define UVM_FLAG_QUERY 0x0400000 /* do everything, + except actual execution */ +#define UVM_FLAG_NOFAULT 0x0800000 /* don't fault */ +#define UVM_FLAG_UNMAP 0x1000000 /* unmap to make space */ +#define UVM_FLAG_STACK 0x2000000 /* page may contain a stack */ +.Ed +.Pp +The +.Dv UVM_MAPFLAG +macro arguments can be combined with an or operator. +There are also some additional macros to extract bits from the flags. +The +.Dv UVM_PROTECTION , +.Dv UVM_INHERIT , +.Dv UVM_MAXPROTECTION +and +.Dv UVM_ADVICE +macros return the protection, inheritance, maximum protection and advice, +respectively. +.Fn uvm_map +returns a standard errno. +.Pp +The +.Fn uvm_map_pageable +function changes the pageability of the pages in the range from +.Fa start +to +.Fa end +in map +.Fa map +to +.Fa new_pageable . +The +.Fn uvm_map_pageable_all +function changes the pageability of all mapped regions. +If +.Fa limit +is non-zero and +.Fn pmap_wired_count +is implemented, +.Dv ENOMEM +is returned if the amount of wired pages exceed +.Fa limit . +The map is locked on entry if +.Fa lockflags +contain +.Dv UVM_LK_ENTER , +and locked on exit if +.Fa lockflags +contain +.Dv UVM_LK_EXIT . +.Fn uvm_map_pageable +and +.Fn uvm_map_pageable_all +return a standard errno. +.Pp +The +.Fn uvm_map_checkprot +function checks the protection of the range from +.Fa start +to +.Fa end +in map +.Fa map +against +.Fa protection . +This returns either +.Dv TRUE +or +.Dv FALSE . +.Pp +The +.Fn uvm_map_protect +function changes the protection +.Fa start +to +.Fa end +in map +.Fa map +to +.Fa new_prot , +also setting the maximum protection to the region to +.Fa new_prot +if +.Fa set_max +is non-zero. +The +.Fa et +parameter should be 0, unless a +.Dv PROT_READ | PROT_WRITE +mapping is being changed to extend the stack limit, then it may be +.Dv UVM_ET_STACK . +This function returns a standard errno. +.Pp +The +.Fn uvmspace_alloc +function allocates and returns a new address space, with ranges from +.Fa min +to +.Fa max , +setting the pageability of the address space to +.Fa pageable . +If +.Fa remove_holes +is non-zero, hardware +.Sq holes +in the virtual address space will be removed from the newly allocated +address space. +.Pp +The +.Fn uvmspace_exec +function either reuses the address space of process +.Fa p +if there are no other references to it, or creates +a new one with +.Fn uvmspace_alloc . +The range of valid addresses in the address space is reset to +.Fa start +through +.Fa end . +.Pp +The +.Fn uvmspace_fork +function creates and returns a new address space based upon the +address space of process +.Fa pr +and is typically used when allocating an address space for a +child process. +.Pp +The +.Fn uvmspace_free +function lowers the reference count on the address space +.Fa vm , +freeing the data structures if there are no other references. +.Pp +The +.Fn uvmspace_share +function returns a reference to the address space of process +.Fa pr , +increasing its reference count. +.Pp +The +.Fn uvm_uarea_alloc +function allocates a thread's +.Sq uarea , +the memory where its kernel stack and PCB are stored. +The +.Fn uvm_uarea_free +function frees the uarea for +thread +.Fa p , +which must no longer be running. +.Sh SEE ALSO +.Xr pmap 9 |