#- # 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 #include #include #include #include #include #include /** * @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 void mmu_null_init2(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, vm_offset_t start, vm_offset_t end) { 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 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. * @param _mpte ??? * * @retval NULL (possibly a hint for future calls ?) */ METHOD vm_page_t enter_quick { mmu_t _mmu; pmap_t _pmap; vm_offset_t _va; vm_page_t _pg; vm_prot_t _prot; vm_page_t _mpte; }; /** * @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 Called from vm_init2/proc0_init, so can be used as a last-chance * init before process scheduling starts. This routine is optional. */ METHOD void init2 { mmu_t _mmu; } DEFAULT mmu_null_init2; /** * @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; vm_offset_t _start; vm_offset_t _end; } 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; };