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/* -> /*- for license, minor formatting changes
2005-01-07 02:29:27 +00:00
/*-
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
* Copyright (c) 1991, 1993
* The Regents of the University of California. 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)vm.h 8.2 (Berkeley) 12/13/93
useracc() the prequel: Merge the contents (less some trivial bordering the silly comments) of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts the #defines for the vm_inherit_t and vm_prot_t types next to their typedefs. This paves the road for the commit to follow shortly: change useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE} as argument.
1999-10-29 18:09:36 +00:00
* @(#)vm_prot.h 8.1 (Berkeley) 6/11/93
* @(#)vm_inherit.h 8.1 (Berkeley) 6/11/93
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
$Id$ -> $FreeBSD$
1999-08-28 01:08:13 +00:00
* $FreeBSD$
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
*/
#ifndef VM_H
#define VM_H
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
#include <machine/vm.h>
useracc() the prequel: Merge the contents (less some trivial bordering the silly comments) of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts the #defines for the vm_inherit_t and vm_prot_t types next to their typedefs. This paves the road for the commit to follow shortly: change useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE} as argument.
1999-10-29 18:09:36 +00:00
typedef char vm_inherit_t; /* inheritance codes */
#define VM_INHERIT_SHARE ((vm_inherit_t) 0)
#define VM_INHERIT_COPY ((vm_inherit_t) 1)
#define VM_INHERIT_NONE ((vm_inherit_t) 2)
#define VM_INHERIT_DEFAULT VM_INHERIT_COPY
Untangled the vm.h include file spaghetti.
1995-12-07 12:48:31 +00:00
typedef u_char vm_prot_t; /* protection codes */
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
useracc() the prequel: Merge the contents (less some trivial bordering the silly comments) of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts the #defines for the vm_inherit_t and vm_prot_t types next to their typedefs. This paves the road for the commit to follow shortly: change useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE} as argument.
1999-10-29 18:09:36 +00:00
#define VM_PROT_NONE ((vm_prot_t) 0x00)
#define VM_PROT_READ ((vm_prot_t) 0x01)
#define VM_PROT_WRITE ((vm_prot_t) 0x02)
#define VM_PROT_EXECUTE ((vm_prot_t) 0x04)
Replace VM_PROT_OVERRIDE_WRITE by VM_PROT_COPY. VM_PROT_OVERRIDE_WRITE has represented a write access that is allowed to override write protection. Until now, VM_PROT_OVERRIDE_WRITE has been used to write breakpoints into text pages. Text pages are not just write protected but they are also copy-on-write. VM_PROT_OVERRIDE_WRITE overrides the write protection on the text page and triggers the replication of the page so that the breakpoint will be written to a private copy. However, here is where things become confused. It is the debugger, not the process being debugged that requires write access to the copied page. Nonetheless, the copied page is being mapped into the process with write access enabled. In other words, once the debugger sets a breakpoint within a text page, the program can write to its private copy of that text page. Whereas prior to setting the breakpoint, a SIGSEGV would have occurred upon a write access. VM_PROT_COPY addresses this problem. The combination of VM_PROT_READ and VM_PROT_COPY forces the replication of a copy-on-write page even though the access is only for read. Moreover, the replicated page is only mapped into the process with read access, and not write access. Reviewed by: kib MFC after: 4 weeks
2009-11-26 05:16:07 +00:00
#define VM_PROT_COPY ((vm_prot_t) 0x08) /* copy-on-read */
useracc() the prequel: Merge the contents (less some trivial bordering the silly comments) of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts the #defines for the vm_inherit_t and vm_prot_t types next to their typedefs. This paves the road for the commit to follow shortly: change useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE} as argument.
1999-10-29 18:09:36 +00:00
#define VM_PROT_ALL (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)
Change the way ELF coredumps are handled. Instead of unconditionally skipping read-only pages, which can result in valuable non-text-related data not getting dumped, the ELF loader and the dynamic loader now mark read-only text pages NOCORE and the coredump code only checks (primarily) for complete inaccessibility of the page or NOCORE being set. Certain applications which map large amounts of read-only data will produce much larger cores. A new sysctl has been added, debug.elf_legacy_coredump, which will revert to the old behavior. This commit represents collaborative work by all parties involved. The PR contains a program demonstrating the problem. PR: kern/45994 Submitted by: "Peter Edwards" <pmedwards@eircom.net>, Archie Cobbs <archie@dellroad.org> Reviewed by: jdp, dillon MFC after: 7 days
2002-12-16 19:24:43 +00:00
#define VM_PROT_RW (VM_PROT_READ|VM_PROT_WRITE)
useracc() the prequel: Merge the contents (less some trivial bordering the silly comments) of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>. This puts the #defines for the vm_inherit_t and vm_prot_t types next to their typedefs. This paves the road for the commit to follow shortly: change useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE} as argument.
1999-10-29 18:09:36 +00:00
#define VM_PROT_DEFAULT VM_PROT_ALL
- Change the vm_mmap() function to accept an objtype_t parameter specifying the type of object represented by the handle argument. - Allow vm_mmap() to map device memory via cdev objects in addition to vnodes and anonymous memory. Note that mmaping a cdev directly does not currently perform any MAC checks like mapping a vnode does. - Unbreak the DRM getbufs ioctl by having it call vm_mmap() directly on the cdev the ioctl is acting on rather than trying to find a suitable vnode to map from. Reviewed by: alc, arch@
2005-04-01 20:00:11 +00:00
enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE, OBJT_PHYS,
Add new pager type, OBJT_MGTDEVICE. It provides the device pager which carries fictitous managed pages. In particular, the consumers of the new object type can remove all mappings of the device page with pmap_remove_all(). The range of physical addresses used for fake page allocation shall be registered with vm_phys_fictitious_reg_range() interface to allow the PHYS_TO_VM_PAGE() to work in pmap. Most likely, only i386 and amd64 pmaps can handle fictitious managed pages right now. Sponsored by: The FreeBSD Foundation Reviewed by: alc MFC after: 1 month
2012-05-12 20:49:58 +00:00
OBJT_DEAD, OBJT_SG, OBJT_MGTDEVICE };
- Change the vm_mmap() function to accept an objtype_t parameter specifying the type of object represented by the handle argument. - Allow vm_mmap() to map device memory via cdev objects in addition to vnodes and anonymous memory. Note that mmaping a cdev directly does not currently perform any MAC checks like mapping a vnode does. - Unbreak the DRM getbufs ioctl by having it call vm_mmap() directly on the cdev the ioctl is acting on rather than trying to find a suitable vnode to map from. Reviewed by: alc, arch@
2005-04-01 20:00:11 +00:00
typedef u_char objtype_t;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
union vm_map_object;
typedef union vm_map_object vm_map_object_t;
struct vm_map_entry;
typedef struct vm_map_entry *vm_map_entry_t;
struct vm_map;
typedef struct vm_map *vm_map_t;
struct vm_object;
typedef struct vm_object *vm_object_t;
Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL" is an application space macro and the applications are supposed to be free to use it as they please (but cannot). This is consistant with the other BSD's who made this change quite some time ago. More commits to come.
1999-12-29 05:07:58 +00:00
#ifndef _KERNEL
Moved the declaration of boolean_t from <vm/vm_param.h> to <sys/types.h> (if KERNEL is defined). This allows removing bogus dependencies on vm stuff in several places (e.g., ddb) and stops <vm_param.h> from depending on <vm_param.h> Added declaration of boolean_t to <vm/vm.h> (if KERNEL is not defined). It never belonged in <vm/vm_param.h>. Unfortunately, it is required for some vm headers that are included by applications. Deleted declarations of TRUE and FALSE from <vm/vm_param.h>. They are defined in <sys/param.h> if KERNEL is defined and we'll soon find out if any applications depend on them being defined in a vm header.
1995-12-10 02:34:29 +00:00
/*
* This is defined in <sys/types.h> for the kernel so that non-vm kernel
* sources (mainly Mach-derived ones such as ddb) don't have to include
* vm stuff. Defining it there for applications might break things.
* Define it here for "applications" that include vm headers (e.g.,
* genassym).
*/
typedef int boolean_t;
Extend the device pager to support different memory attributes on different pages in an object. - Add a new variant of d_mmap() currently called d_mmap2() which accepts an additional in/out parameter that is the memory attribute to use for the requested page. - A driver either uses d_mmap() or d_mmap2() for all requests but not both. The current implementation uses a flag in the cdevsw (D_MMAP2) to indicate that the driver provides a d_mmap2() handler instead of d_mmap(). This is done to make the change ABI compatible with existing drivers and MFC'able to 7 and 8. Submitted by: alc MFC after: 1 month
2009-08-28 14:06:55 +00:00
/*
Add new bus methods for mapping resources. Add a pair of bus methods that can be used to "map" resources for direct CPU access using bus_space(9). bus_map_resource() creates a mapping and bus_unmap_resource() releases a previously created mapping. Mappings are described by 'struct resource_map' object. Pointers to these objects can be passed as the first argument to the bus_space wrapper API used for bus resources. Drivers that wish to map all of a resource using default settings (for example, using uncacheable memory attributes) do not need to change. However, drivers that wish to use non-default settings can now do so without jumping through hoops. First, an RF_UNMAPPED flag is added to request that a resource is not implicitly mapped with the default settings when it is activated. This permits other activation steps (such as enabling I/O or memory decoding in a device's PCI command register) to be taken without creating a mapping. Right now the AGP drivers don't set RF_ACTIVE to avoid using up a large amount of KVA to map the AGP aperture on 32-bit platforms. Once RF_UNMAPPED is supported on all platforms that support AGP this can be changed to using RF_UNMAPPED with RF_ACTIVE instead. Second, bus_map_resource accepts an optional structure that defines additional settings for a given mapping. For example, a driver can now request to map only a subset of a resource instead of the entire range. The AGP driver could also use this to only map the first page of the aperture (IIRC, it calls pmap_mapdev() directly to map the first page currently). I will also eventually change the PCI-PCI bridge driver to request mappings of the subset of the I/O window resource on its parent side to create mappings for child devices rather than passing child resources directly up to nexus to be mapped. This also permits bridges that do address translation to request suitable mappings from a resource on the "upper" side of the bus when mapping resources on the "lower" side of the bus. Another attribute that can be specified is an alternate memory attribute for memory-mapped resources. This can be used to request a Write-Combining mapping of a PCI BAR in an MI fashion. (Currently the drivers that do this call pmap_change_attr() directly for x86 only.) Note that this commit only adds the MI framework. Each platform needs to add support for handling RF_UNMAPPED and thew new bus_map/unmap_resource methods. Generally speaking, any drivers that are calling rman_set_bustag() and rman_set_bushandle() need to be updated. Discussed on: arch Reviewed by: cem Differential Revision: https://reviews.freebsd.org/D5237
2016-05-20 17:57:47 +00:00
* The exact set of memory attributes is machine dependent. However,
* every machine is required to define VM_MEMATTR_DEFAULT and
* VM_MEMATTR_UNCACHEABLE.
Extend the device pager to support different memory attributes on different pages in an object. - Add a new variant of d_mmap() currently called d_mmap2() which accepts an additional in/out parameter that is the memory attribute to use for the requested page. - A driver either uses d_mmap() or d_mmap2() for all requests but not both. The current implementation uses a flag in the cdevsw (D_MMAP2) to indicate that the driver provides a d_mmap2() handler instead of d_mmap(). This is done to make the change ABI compatible with existing drivers and MFC'able to 7 and 8. Submitted by: alc MFC after: 1 month
2009-08-28 14:06:55 +00:00
*/
typedef char vm_memattr_t; /* memory attribute codes */
Moved the declaration of vm_object_t from <vm/vm.h> to <sys/types.h> (if KERNEL is defined). This allows removing the #includes of vm stuff in vnode_if.h, which will speed up the compilation of LINT by about 5%.
1995-12-05 20:54:42 +00:00
/*
* This is defined in <sys/types.h> for the kernel so that vnode_if.h
* doesn't have to include <vm/vm.h>.
*/
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
struct vm_page;
These changes embody the support of the fully coherent merged VM buffer cache, much higher filesystem I/O performance, and much better paging performance. It represents the culmination of over 6 months of R&D. The majority of the merged VM/cache work is by John Dyson. The following highlights the most significant changes. Additionally, there are (mostly minor) changes to the various filesystem modules (nfs, msdosfs, etc) to support the new VM/buffer scheme. vfs_bio.c: Significant rewrite of most of vfs_bio to support the merged VM buffer cache scheme. The scheme is almost fully compatible with the old filesystem interface. Significant improvement in the number of opportunities for write clustering. vfs_cluster.c, vfs_subr.c Upgrade and performance enhancements in vfs layer code to support merged VM/buffer cache. Fixup of vfs_cluster to eliminate the bogus pagemove stuff. vm_object.c: Yet more improvements in the collapse code. Elimination of some windows that can cause list corruption. vm_pageout.c: Fixed it, it really works better now. Somehow in 2.0, some "enhancements" broke the code. This code has been reworked from the ground-up. vm_fault.c, vm_page.c, pmap.c, vm_object.c Support for small-block filesystems with merged VM/buffer cache scheme. pmap.c vm_map.c Dynamic kernel VM size, now we dont have to pre-allocate excessive numbers of kernel PTs. vm_glue.c Much simpler and more effective swapping code. No more gratuitous swapping. proc.h Fixed the problem that the p_lock flag was not being cleared on a fork. swap_pager.c, vnode_pager.c Removal of old vfs_bio cruft to support the past pseudo-coherency. Now the code doesn't need it anymore. machdep.c Changes to better support the parameter values for the merged VM/buffer cache scheme. machdep.c, kern_exec.c, vm_glue.c Implemented a seperate submap for temporary exec string space and another one to contain process upages. This eliminates all map fragmentation problems that previously existed. ffs_inode.c, ufs_inode.c, ufs_readwrite.c Changes for merged VM/buffer cache. Add "bypass" support for sneaking in on busy buffers. Submitted by: John Dyson and David Greenman
1995-01-09 16:06:02 +00:00
typedef struct vm_page *vm_page_t;
- Remove a number of extra newlines that do not belong here according to style(9) - Minor space adjustment in cases where we have "( ", " )", if(), return(), while(), for(), etc. - Add /* SYMBOL */ after a few #endifs. Reviewed by: alc
2002-03-10 21:52:48 +00:00
#endif /* _KERNEL */
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Add the superpage reservation type.
2007-12-27 17:08:11 +00:00
struct vm_reserv;
typedef struct vm_reserv *vm_reserv_t;
Move most of the kernel submap initialization code, including the timeout callwheel and buffer cache, out of the platform specific areas and into the machine independant area. i386 and alpha adjusted here. Other cpus can be fixed piecemeal. Reviewed by: freebsd-smp, jake
2001-08-22 04:07:27 +00:00
/*
* Information passed from the machine-independant VM initialization code
* for use by machine-dependant code (mainly for MMU support)
*/
struct kva_md_info {
vm_offset_t buffer_sva;
vm_offset_t buffer_eva;
vm_offset_t clean_sva;
vm_offset_t clean_eva;
};
extern struct kva_md_info kmi;
Remove a parameter name from a prototype.
2002-01-25 21:33:10 +00:00
extern void vm_ksubmap_init(struct kva_md_info *);
Move most of the kernel submap initialization code, including the timeout callwheel and buffer cache, out of the platform specific areas and into the machine independant area. i386 and alpha adjusted here. Other cpus can be fixed piecemeal. Reviewed by: freebsd-smp, jake
2001-08-22 04:07:27 +00:00
- Fix locked memory accounting for maps with MAP_WIREFUTURE flag. - Add sysctl vm.old_mlock which may turn such accounting off. Reviewed by: avg, trasz Approved by: kib (mentor) MFC after: 1 week
2012-12-18 07:35:01 +00:00
extern int old_mlock;
Replace pointer to "struct uidinfo" with pointer to "struct ucred" in "struct vm_object". This is required to make it possible to account for per-jail swap usage. Reviewed by: kib@ Tested by: pho@ Sponsored by: FreeBSD Foundation
2010-12-02 17:37:16 +00:00
struct ucred;
Implement global and per-uid accounting of the anonymous memory. Add rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved for the uid. The accounting information (charge) is associated with either map entry, or vm object backing the entry, assuming the object is the first one in the shadow chain and entry does not require COW. Charge is moved from entry to object on allocation of the object, e.g. during the mmap, assuming the object is allocated, or on the first page fault on the entry. It moves back to the entry on forks due to COW setup. The per-entry granularity of accounting makes the charge process fair for processes that change uid during lifetime, and decrements charge for proper uid when region is unmapped. The interface of vm_pager_allocate(9) is extended by adding struct ucred *, that is used to charge appropriate uid when allocation if performed by kernel, e.g. md(4). Several syscalls, among them is fork(2), may now return ENOMEM when global or per-uid limits are enforced. In collaboration with: pho Reviewed by: alc Approved by: re (kensmith)
2009-06-23 20:45:22 +00:00
int swap_reserve(vm_ooffset_t incr);
Replace pointer to "struct uidinfo" with pointer to "struct ucred" in "struct vm_object". This is required to make it possible to account for per-jail swap usage. Reviewed by: kib@ Tested by: pho@ Sponsored by: FreeBSD Foundation
2010-12-02 17:37:16 +00:00
int swap_reserve_by_cred(vm_ooffset_t incr, struct ucred *cred);
Implement global and per-uid accounting of the anonymous memory. Add rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved for the uid. The accounting information (charge) is associated with either map entry, or vm object backing the entry, assuming the object is the first one in the shadow chain and entry does not require COW. Charge is moved from entry to object on allocation of the object, e.g. during the mmap, assuming the object is allocated, or on the first page fault on the entry. It moves back to the entry on forks due to COW setup. The per-entry granularity of accounting makes the charge process fair for processes that change uid during lifetime, and decrements charge for proper uid when region is unmapped. The interface of vm_pager_allocate(9) is extended by adding struct ucred *, that is used to charge appropriate uid when allocation if performed by kernel, e.g. md(4). Several syscalls, among them is fork(2), may now return ENOMEM when global or per-uid limits are enforced. In collaboration with: pho Reviewed by: alc Approved by: re (kensmith)
2009-06-23 20:45:22 +00:00
void swap_reserve_force(vm_ooffset_t incr);
void swap_release(vm_ooffset_t decr);
Replace pointer to "struct uidinfo" with pointer to "struct ucred" in "struct vm_object". This is required to make it possible to account for per-jail swap usage. Reviewed by: kib@ Tested by: pho@ Sponsored by: FreeBSD Foundation
2010-12-02 17:37:16 +00:00
void swap_release_by_cred(vm_ooffset_t decr, struct ucred *cred);
rename scheduler->swapper and SI_SUB_RUN_SCHEDULER->SI_SUB_LAST Also directly call swapper() at the end of mi_startup instead of relying on swapper being the last thing in sysinits order. Rationale: - "RUN_SCHEDULER" was misleading, scheduling already takes place at that stage - "scheduler" was misleading, the function swaps in the swapped out processes - another SYSINIT(SI_SUB_RUN_SCHEDULER, SI_ORDER_ANY) could never be invoked depending on its relative order with scheduler; this was not obvious and the bug actually used to exist Reviewed by: kib (ealier version) MFC after: 14 days
2013-07-24 09:45:31 +00:00
void swapper(void);
Implement global and per-uid accounting of the anonymous memory. Add rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved for the uid. The accounting information (charge) is associated with either map entry, or vm object backing the entry, assuming the object is the first one in the shadow chain and entry does not require COW. Charge is moved from entry to object on allocation of the object, e.g. during the mmap, assuming the object is allocated, or on the first page fault on the entry. It moves back to the entry on forks due to COW setup. The per-entry granularity of accounting makes the charge process fair for processes that change uid during lifetime, and decrements charge for proper uid when region is unmapped. The interface of vm_pager_allocate(9) is extended by adding struct ucred *, that is used to charge appropriate uid when allocation if performed by kernel, e.g. md(4). Several syscalls, among them is fork(2), may now return ENOMEM when global or per-uid limits are enforced. In collaboration with: pho Reviewed by: alc Approved by: re (kensmith)
2009-06-23 20:45:22 +00:00
These changes embody the support of the fully coherent merged VM buffer cache, much higher filesystem I/O performance, and much better paging performance. It represents the culmination of over 6 months of R&D. The majority of the merged VM/cache work is by John Dyson. The following highlights the most significant changes. Additionally, there are (mostly minor) changes to the various filesystem modules (nfs, msdosfs, etc) to support the new VM/buffer scheme. vfs_bio.c: Significant rewrite of most of vfs_bio to support the merged VM buffer cache scheme. The scheme is almost fully compatible with the old filesystem interface. Significant improvement in the number of opportunities for write clustering. vfs_cluster.c, vfs_subr.c Upgrade and performance enhancements in vfs layer code to support merged VM/buffer cache. Fixup of vfs_cluster to eliminate the bogus pagemove stuff. vm_object.c: Yet more improvements in the collapse code. Elimination of some windows that can cause list corruption. vm_pageout.c: Fixed it, it really works better now. Somehow in 2.0, some "enhancements" broke the code. This code has been reworked from the ground-up. vm_fault.c, vm_page.c, pmap.c, vm_object.c Support for small-block filesystems with merged VM/buffer cache scheme. pmap.c vm_map.c Dynamic kernel VM size, now we dont have to pre-allocate excessive numbers of kernel PTs. vm_glue.c Much simpler and more effective swapping code. No more gratuitous swapping. proc.h Fixed the problem that the p_lock flag was not being cleared on a fork. swap_pager.c, vnode_pager.c Removal of old vfs_bio cruft to support the past pseudo-coherency. Now the code doesn't need it anymore. machdep.c Changes to better support the parameter values for the merged VM/buffer cache scheme. machdep.c, kern_exec.c, vm_glue.c Implemented a seperate submap for temporary exec string space and another one to contain process upages. This eliminates all map fragmentation problems that previously existed. ffs_inode.c, ufs_inode.c, ufs_readwrite.c Changes for merged VM/buffer cache. Add "bypass" support for sneaking in on busy buffers. Submitted by: John Dyson and David Greenman
1995-01-09 16:06:02 +00:00
#endif /* VM_H */
Move most of the kernel submap initialization code, including the timeout callwheel and buffer cache, out of the platform specific areas and into the machine independant area. i386 and alpha adjusted here. Other cpus can be fixed piecemeal. Reviewed by: freebsd-smp, jake
2001-08-22 04:07:27 +00:00
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