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freebsd-dev/sys/amd64/include/vm.h

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This change is the next step in implementing the cache control functionality required by video card drivers. Specifically, this change introduces vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all architectures. In addition, this changes adds a vm_cache_mode_t parameter to kmem_alloc_contig() and vm_phys_alloc_contig(). These will be the interfaces for allocating mapped kernel memory and physical memory, respectively, with non-default cache modes. In collaboration with: jhb
2009-06-26 04:47:43 +00:00
/*-
* Copyright (c) 2009 Advanced Computing Technologies LLC
* Written by: John H. Baldwin <jhb@FreeBSD.org>
* 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.
*
* $FreeBSD$
*/
#ifndef _MACHINE_VM_H_
#define _MACHINE_VM_H_
#include <machine/specialreg.h>
Add support to the virtual memory system for configuring machine- dependent memory attributes: Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the fact that there are machine-dependent memory attributes that have nothing to do with controlling the cache's behavior. Introduce vm_object_set_memattr() for setting the default memory attributes that will be given to an object's pages. Introduce and use pmap_page_{get,set}_memattr() for getting and setting a page's machine-dependent memory attributes. Add full support for these functions on amd64 and i386 and stubs for them on the other architectures. The function pmap_page_set_memattr() is also responsible for any other machine-dependent aspects of changing a page's memory attributes, such as flushing the cache or updating the direct map. The uses include kmem_alloc_contig(), vm_page_alloc(), and the device pager: kmem_alloc_contig() can now be used to allocate kernel memory with non-default memory attributes on amd64 and i386. vm_page_alloc() and the device pager will set the memory attributes for the real or fictitious page according to the object's default memory attributes. Update the various pmap functions on amd64 and i386 that map pages to incorporate each page's memory attributes in the mapping. Notes: (1) Inherent to this design are safety features that prevent the specification of inconsistent memory attributes by different mappings on amd64 and i386. In addition, the device pager provides a warning when a device driver creates a fictitious page with memory attributes that are inconsistent with the real page that the fictitious page is an alias for. (2) Storing the machine-dependent memory attributes for amd64 and i386 as a dedicated "int" in "struct md_page" represents a compromise between space efficiency and the ease of MFCing these changes to RELENG_7. In collaboration with: jhb Approved by: re (kib)
2009-07-12 23:31:20 +00:00
/* Memory attributes. */
#define VM_MEMATTR_UNCACHEABLE ((vm_memattr_t)PAT_UNCACHEABLE)
#define VM_MEMATTR_WRITE_COMBINING ((vm_memattr_t)PAT_WRITE_COMBINING)
#define VM_MEMATTR_WRITE_THROUGH ((vm_memattr_t)PAT_WRITE_THROUGH)
#define VM_MEMATTR_WRITE_PROTECTED ((vm_memattr_t)PAT_WRITE_PROTECTED)
#define VM_MEMATTR_WRITE_BACK ((vm_memattr_t)PAT_WRITE_BACK)
#define VM_MEMATTR_UNCACHED ((vm_memattr_t)PAT_UNCACHED)
This change is the next step in implementing the cache control functionality required by video card drivers. Specifically, this change introduces vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all architectures. In addition, this changes adds a vm_cache_mode_t parameter to kmem_alloc_contig() and vm_phys_alloc_contig(). These will be the interfaces for allocating mapped kernel memory and physical memory, respectively, with non-default cache modes. In collaboration with: jhb
2009-06-26 04:47:43 +00:00
Add support to the virtual memory system for configuring machine- dependent memory attributes: Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the fact that there are machine-dependent memory attributes that have nothing to do with controlling the cache's behavior. Introduce vm_object_set_memattr() for setting the default memory attributes that will be given to an object's pages. Introduce and use pmap_page_{get,set}_memattr() for getting and setting a page's machine-dependent memory attributes. Add full support for these functions on amd64 and i386 and stubs for them on the other architectures. The function pmap_page_set_memattr() is also responsible for any other machine-dependent aspects of changing a page's memory attributes, such as flushing the cache or updating the direct map. The uses include kmem_alloc_contig(), vm_page_alloc(), and the device pager: kmem_alloc_contig() can now be used to allocate kernel memory with non-default memory attributes on amd64 and i386. vm_page_alloc() and the device pager will set the memory attributes for the real or fictitious page according to the object's default memory attributes. Update the various pmap functions on amd64 and i386 that map pages to incorporate each page's memory attributes in the mapping. Notes: (1) Inherent to this design are safety features that prevent the specification of inconsistent memory attributes by different mappings on amd64 and i386. In addition, the device pager provides a warning when a device driver creates a fictitious page with memory attributes that are inconsistent with the real page that the fictitious page is an alias for. (2) Storing the machine-dependent memory attributes for amd64 and i386 as a dedicated "int" in "struct md_page" represents a compromise between space efficiency and the ease of MFCing these changes to RELENG_7. In collaboration with: jhb Approved by: re (kib)
2009-07-12 23:31:20 +00:00
#define VM_MEMATTR_DEFAULT VM_MEMATTR_WRITE_BACK
This change is the next step in implementing the cache control functionality required by video card drivers. Specifically, this change introduces vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all architectures. In addition, this changes adds a vm_cache_mode_t parameter to kmem_alloc_contig() and vm_phys_alloc_contig(). These will be the interfaces for allocating mapped kernel memory and physical memory, respectively, with non-default cache modes. In collaboration with: jhb
2009-06-26 04:47:43 +00:00
Correct the #endif comment. Noticed by: jmallett Approved by: re (kib)
2009-06-26 16:22:24 +00:00
#endif /* !_MACHINE_VM_H_ */
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