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|
#-
# Copyright (c) 2005 Peter Grehan
# 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.
#
# $FreeBSD$
#
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/systm.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <machine/mmuvar.h>
/**
* @defgroup MMU mmu - KObj methods for PowerPC MMU implementations
* @brief A set of methods required by all MMU implementations. These
* are basically direct call-thru's from the pmap machine-dependent
* code.
* Thanks to Bruce M Simpson's pmap man pages for routine descriptions.
*@{
*/
INTERFACE mmu;
#
# Default implementations of some methods
#
CODE {
static void mmu_null_copy(mmu_t mmu, pmap_t dst_pmap, pmap_t src_pmap,
vm_offset_t dst_addr, vm_size_t len, vm_offset_t src_addr)
{
return;
}
static void mmu_null_growkernel(mmu_t mmu, vm_offset_t addr)
{
return;
}
static void mmu_null_init(mmu_t mmu)
{
return;
}
static boolean_t mmu_null_is_prefaultable(mmu_t mmu, pmap_t pmap,
vm_offset_t va)
{
return (FALSE);
}
static void mmu_null_object_init_pt(mmu_t mmu, pmap_t pmap,
vm_offset_t addr, vm_object_t object, vm_pindex_t index,
vm_size_t size)
{
return;
}
static void mmu_null_page_init(mmu_t mmu, vm_page_t m)
{
return;
}
static void mmu_null_remove_pages(mmu_t mmu, pmap_t pmap)
{
return;
}
static int mmu_null_mincore(mmu_t mmu, pmap_t pmap, vm_offset_t addr)
{
return (0);
}
static void mmu_null_deactivate(struct thread *td)
{
return;
}
static vm_offset_t mmu_null_addr_hint(mmu_t mmu, vm_object_t object,
vm_offset_t va, vm_size_t size)
{
return (va);
}
};
/**
* @brief Change the wiring attribute for the page in the given physical
* map and virtual address.
*
* @param _pmap physical map of page
* @param _va page virtual address
* @param _wired TRUE to increment wired count, FALSE to decrement
*/
METHOD void change_wiring {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _va;
boolean_t _wired;
};
/**
* @brief Clear the 'modified' bit on the given physical page
*
* @param _pg physical page
*/
METHOD void clear_modify {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Clear the 'referenced' bit on the given physical page
*
* @param _pg physical page
*/
METHOD void clear_reference {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Copy the address range given by the source physical map, virtual
* address and length to the destination physical map and virtual address.
* This routine is optional (xxx default null implementation ?)
*
* @param _dst_pmap destination physical map
* @param _src_pmap source physical map
* @param _dst_addr destination virtual address
* @param _len size of range
* @param _src_addr source virtual address
*/
METHOD void copy {
mmu_t _mmu;
pmap_t _dst_pmap;
pmap_t _src_pmap;
vm_offset_t _dst_addr;
vm_size_t _len;
vm_offset_t _src_addr;
} DEFAULT mmu_null_copy;
/**
* @brief Copy the source physical page to the destination physical page
*
* @param _src source physical page
* @param _dst destination physical page
*/
METHOD void copy_page {
mmu_t _mmu;
vm_page_t _src;
vm_page_t _dst;
};
/**
* @brief Create a mapping between a virtual/physical address pair in the
* passed physical map with the specified protection and wiring
*
* @param _pmap physical map
* @param _va mapping virtual address
* @param _p mapping physical page
* @param _prot mapping page protection
* @param _wired TRUE if page will be wired
*/
METHOD void enter {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _va;
vm_page_t _p;
vm_prot_t _prot;
boolean_t _wired;
};
/**
* @brief Maps a sequence of resident pages belonging to the same object.
*
* @param _pmap physical map
* @param _start virtual range start
* @param _end virtual range end
* @param _m_start physical page mapped at start
* @param _prot mapping page protection
*/
METHOD void enter_object {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _start;
vm_offset_t _end;
vm_page_t _m_start;
vm_prot_t _prot;
};
/**
* @brief A faster entry point for page mapping where it is possible
* to short-circuit some of the tests in pmap_enter.
*
* @param _pmap physical map (and also currently active pmap)
* @param _va mapping virtual address
* @param _pg mapping physical page
* @param _prot new page protection - used to see if page is exec.
*/
METHOD void enter_quick {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _va;
vm_page_t _pg;
vm_prot_t _prot;
};
/**
* @brief Reverse map the given virtual address, returning the physical
* page associated with the address if a mapping exists.
*
* @param _pmap physical map
* @param _va mapping virtual address
*
* @retval 0 No mapping found
* @retval addr The mapping physical address
*/
METHOD vm_paddr_t extract {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _va;
};
/**
* @brief Reverse map the given virtual address, returning the
* physical page if found. The page must be held (by calling
* vm_page_hold) if the page protection matches the given protection
*
* @param _pmap physical map
* @param _va mapping virtual address
* @param _prot protection used to determine if physical page
* should be locked
*
* @retval NULL No mapping found
* @retval page Pointer to physical page. Held if protections match
*/
METHOD vm_page_t extract_and_hold {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _va;
vm_prot_t _prot;
};
/**
* @brief Increase kernel virtual address space to the given virtual address.
* Not really required for PowerPC, so optional unless the MMU implementation
* can use it.
*
* @param _va new upper limit for kernel virtual address space
*/
METHOD void growkernel {
mmu_t _mmu;
vm_offset_t _va;
} DEFAULT mmu_null_growkernel;
/**
* @brief Called from vm_mem_init. Zone allocation is available at
* this stage so a convenient time to create zones. This routine is
* for MMU-implementation convenience and is optional.
*/
METHOD void init {
mmu_t _mmu;
} DEFAULT mmu_null_init;
/**
* @brief Return if the page has been marked by MMU hardware to have been
* modified
*
* @param _pg physical page to test
*
* @retval boolean TRUE if page has been modified
*/
METHOD boolean_t is_modified {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Return whether the specified virtual address is a candidate to be
* prefaulted in. This routine is optional.
*
* @param _pmap physical map
* @param _va virtual address to test
*
* @retval boolean TRUE if the address is a candidate.
*/
METHOD boolean_t is_prefaultable {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _va;
} DEFAULT mmu_null_is_prefaultable;
/**
* @brief Return a count of referenced bits for a page, clearing those bits.
* Not all referenced bits need to be cleared, but it is necessary that 0
* only be returned when there are none set.
*
* @params _m physical page
*
* @retval int count of referenced bits
*/
METHOD boolean_t ts_referenced {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Map the requested physical address range into kernel virtual
* address space. The value in _virt is taken as a hint. The virtual
* address of the range is returned, or NULL if the mapping could not
* be created. The range can be direct-mapped if that is supported.
*
* @param *_virt Hint for start virtual address, and also return
* value
* @param _start physical address range start
* @param _end physical address range end
* @param _prot protection of range (currently ignored)
*
* @retval NULL could not map the area
* @retval addr, *_virt mapping start virtual address
*/
METHOD vm_offset_t map {
mmu_t _mmu;
vm_offset_t *_virt;
vm_paddr_t _start;
vm_paddr_t _end;
int _prot;
};
/**
* @brief Used to create a contiguous set of read-only mappings for a
* given object to try and eliminate a cascade of on-demand faults as
* the object is accessed sequentially. This routine is optional.
*
* @param _pmap physical map
* @param _addr mapping start virtual address
* @param _object device-backed V.M. object to be mapped
* @param _pindex page-index within object of mapping start
* @param _size size in bytes of mapping
*/
METHOD void object_init_pt {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _addr;
vm_object_t _object;
vm_pindex_t _pindex;
vm_size_t _size;
} DEFAULT mmu_null_object_init_pt;
/**
* @brief Used to determine if the specified page has a mapping for the
* given physical map, by scanning the list of reverse-mappings from the
* page. The list is scanned to a maximum of 16 entries.
*
* @param _pmap physical map
* @param _pg physical page
*
* @retval bool TRUE if the physical map was found in the first 16
* reverse-map list entries off the physical page.
*/
METHOD boolean_t page_exists_quick {
mmu_t _mmu;
pmap_t _pmap;
vm_page_t _pg;
};
/**
* @brief Initialise the machine-dependent section of the physical page
* data structure. This routine is optional.
*
* @param _pg physical page
*/
METHOD void page_init {
mmu_t _mmu;
vm_page_t _pg;
} DEFAULT mmu_null_page_init;
/**
* @brief Lower the protection to the given value for all mappings of the
* given physical page.
*
* @param _pg physical page
* @param _prot updated page protection
*/
METHOD void page_protect {
mmu_t _mmu;
vm_page_t _pg;
vm_prot_t _prot;
};
/**
* @brief Initialise a physical map data structure
*
* @param _pmap physical map
*/
METHOD void pinit {
mmu_t _mmu;
pmap_t _pmap;
};
/**
* @brief Initialise the physical map for process 0, the initial process
* in the system.
* XXX default to pinit ?
*
* @param _pmap physical map
*/
METHOD void pinit0 {
mmu_t _mmu;
pmap_t _pmap;
};
/**
* @brief Set the protection for physical pages in the given virtual address
* range to the given value.
*
* @param _pmap physical map
* @param _start virtual range start
* @param _end virtual range end
* @param _prot new page protection
*/
METHOD void protect {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _start;
vm_offset_t _end;
vm_prot_t _prot;
};
/**
* @brief Create a mapping in kernel virtual address space for the given array
* of wired physical pages.
*
* @param _start mapping virtual address start
* @param *_m array of physical page pointers
* @param _count array elements
*/
METHOD void qenter {
mmu_t _mmu;
vm_offset_t _start;
vm_page_t *_pg;
int _count;
};
/**
* @brief Remove the temporary mappings created by qenter.
*
* @param _start mapping virtual address start
* @param _count number of pages in mapping
*/
METHOD void qremove {
mmu_t _mmu;
vm_offset_t _start;
int _count;
};
/**
* @brief Release per-pmap resources, e.g. mutexes, allocated memory etc. There
* should be no existing mappings for the physical map at this point
*
* @param _pmap physical map
*/
METHOD void release {
mmu_t _mmu;
pmap_t _pmap;
};
/**
* @brief Remove all mappings in the given physical map for the start/end
* virtual address range. The range will be page-aligned.
*
* @param _pmap physical map
* @param _start mapping virtual address start
* @param _end mapping virtual address end
*/
METHOD void remove {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _start;
vm_offset_t _end;
};
/**
* @brief Traverse the reverse-map list off the given physical page and
* remove all mappings. Clear the PG_WRITEABLE attribute from the page.
*
* @param _pg physical page
*/
METHOD void remove_all {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Remove all mappings in the given start/end virtual address range
* for the given physical map. Similar to the remove method, but it used
* when tearing down all mappings in an address space. This method is
* optional, since pmap_remove will be called for each valid vm_map in
* the address space later.
*
* @param _pmap physical map
* @param _start mapping virtual address start
* @param _end mapping virtual address end
*/
METHOD void remove_pages {
mmu_t _mmu;
pmap_t _pmap;
} DEFAULT mmu_null_remove_pages;
/**
* @brief Zero a physical page. It is not assumed that the page is mapped,
* so a temporary (or direct) mapping may need to be used.
*
* @param _pg physical page
*/
METHOD void zero_page {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Zero a portion of a physical page, starting at a given offset and
* for a given size (multiples of 512 bytes for 4k pages).
*
* @param _pg physical page
* @param _off byte offset from start of page
* @param _size size of area to zero
*/
METHOD void zero_page_area {
mmu_t _mmu;
vm_page_t _pg;
int _off;
int _size;
};
/**
* @brief Called from the idle loop to zero pages. XXX I think locking
* constraints might be different here compared to zero_page.
*
* @param _pg physical page
*/
METHOD void zero_page_idle {
mmu_t _mmu;
vm_page_t _pg;
};
/**
* @brief Extract mincore(2) information from a mapping. This routine is
* optional and is an optimisation: the mincore code will call is_modified
* and ts_referenced if no result is returned.
*
* @param _pmap physical map
* @param _addr page virtual address
*
* @retval 0 no result
* @retval non-zero mincore(2) flag values
*/
METHOD int mincore {
mmu_t _mmu;
pmap_t _pmap;
vm_offset_t _addr;
} DEFAULT mmu_null_mincore;
/**
* @brief Perform any operations required to allow a physical map to be used
* before it's address space is accessed.
*
* @param _td thread associated with physical map
*/
METHOD void activate {
mmu_t _mmu;
struct thread *_td;
};
/**
* @brief Perform any operations required to deactivate a physical map,
* for instance as it is context-switched out.
*
* @param _td thread associated with physical map
*/
METHOD void deactivate {
mmu_t _mmu;
struct thread *_td;
} DEFAULT mmu_null_deactivate;
/**
* @brief Return a hint for the best virtual address to map a tentative
* virtual address range in a given VM object. The default is to just
* return the given tentative start address.
*
* @param _obj VM backing object
* @param _addr initial guess at virtual address
* @param _size size of virtual address range
*/
METHOD vm_offset_t addr_hint {
mmu_t _mmu;
vm_object_t _obj;
vm_offset_t _addr;
vm_size_t _size;
} DEFAULT mmu_null_addr_hint;
/**
* INTERNAL INTERFACES
*/
/**
* @brief Bootstrap the VM system. At the completion of this routine, the
* kernel will be running in it's own address space with full control over
* paging.
*
* @param _start start of reserved memory (obsolete ???)
* @param _end end of reserved memory (obsolete ???)
* XXX I think the intent of these was to allow
* the memory used by kernel text+data+bss and
* loader variables/load-time kld's to be carved out
* of available physical mem.
*
*/
METHOD void bootstrap {
mmu_t _mmu;
vm_offset_t _start;
vm_offset_t _end;
};
/**
* @brief Create a kernel mapping for a given physical address range.
* Called by bus code on behalf of device drivers. The mapping does not
* have to be a virtual address: it can be a direct-mapped physical address
* if that is supported by the MMU.
*
* @param _pa start physical address
* @param _size size in bytes of mapping
*
* @retval addr address of mapping.
*/
METHOD void * mapdev {
mmu_t _mmu;
vm_offset_t _pa;
vm_size_t _size;
};
/**
* @brief Remove the mapping created by mapdev. Called when a driver
* is unloaded.
*
* @param _va Mapping address returned from mapdev
* @param _size size in bytes of mapping
*/
METHOD void unmapdev {
mmu_t _mmu;
vm_offset_t _va;
vm_size_t _size;
};
/**
* @brief Reverse-map a kernel virtual address
*
* @param _va kernel virtual address to reverse-map
*
* @retval pa physical address corresponding to mapping
*/
METHOD vm_offset_t kextract {
mmu_t _mmu;
vm_offset_t _va;
};
/**
* @brief Map a wired page into kernel virtual address space
*
* @param _va mapping virtual address
* @param _pa mapping physical address
*/
METHOD void kenter {
mmu_t _mmu;
vm_offset_t _va;
vm_offset_t _pa;
};
/**
* @brief Determine if the given physical address range has been direct-mapped.
*
* @param _pa physical address start
* @param _size physical address range size
*
* @retval bool TRUE if the range is direct-mapped.
*/
METHOD boolean_t dev_direct_mapped {
mmu_t _mmu;
vm_offset_t _pa;
vm_size_t _size;
};
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