sanchayanmaity/minix
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
minix/servers/vm/mem_anon_contig.c

112 lines
3 KiB
C
Raw Normal View History

VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
/* This file implements the methods of physically contiguous anonymous memory. */
#include <assert.h>
#include "proto.h"
#include "vm.h"
#include "region.h"
#include "glo.h"
vm: new secondary cache code Primary purpose of change: to support the mmap implementation, VM must know both (a) about some block metadata for FS cache blocks, i.e. inode numbers and inode offsets where applicable; and (b) know about *all* cache blocks, i.e. also of the FS primary caches and not just the blocks that spill into the secondary one. This changes the interface and VM data structures. This change is only for the interface (libminixfs) and VM data structures; the filesystem code is unmodified, so although the secondary cache will be used as normal, blocks will not be annotated with inode information until the FS is modified to provide this information. Until it is modified, mmap of files will fail gracefully on such filesystems. This is indicated to VFS/VM by returning ENOSYS for REQ_PEEK. Change-Id: I1d2df6c485e6c5e89eb28d9055076cc02629594e
2013-03-20 20:18:52 +01:00
static int anon_contig_reference(struct phys_region *, struct phys_region *);
VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
static int anon_contig_unreference(struct phys_region *pr);
static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
vm: new secondary cache code Primary purpose of change: to support the mmap implementation, VM must know both (a) about some block metadata for FS cache blocks, i.e. inode numbers and inode offsets where applicable; and (b) know about *all* cache blocks, i.e. also of the FS primary caches and not just the blocks that spill into the secondary one. This changes the interface and VM data structures. This change is only for the interface (libminixfs) and VM data structures; the filesystem code is unmodified, so although the secondary cache will be used as normal, blocks will not be annotated with inode information until the FS is modified to provide this information. Until it is modified, mmap of files will fail gracefully on such filesystems. This is indicated to VFS/VM by returning ENOSYS for REQ_PEEK. Change-Id: I1d2df6c485e6c5e89eb28d9055076cc02629594e
2013-03-20 20:18:52 +01:00
struct phys_region *ph, int write, vfs_callback_t cb, void *st, int);
VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line);
static int anon_contig_writable(struct phys_region *pr);
static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l);
static int anon_contig_new(struct vir_region *vr);
struct mem_type mem_type_anon_contig = {
.name = "anonymous memory (physically contiguous)",
.ev_new = anon_contig_new,
.ev_reference = anon_contig_reference,
.ev_unreference = anon_contig_unreference,
.ev_pagefault = anon_contig_pagefault,
.ev_resize = anon_contig_resize,
.ev_sanitycheck = anon_contig_sanitycheck,
.writable = anon_contig_writable
};
static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
vm: new secondary cache code Primary purpose of change: to support the mmap implementation, VM must know both (a) about some block metadata for FS cache blocks, i.e. inode numbers and inode offsets where applicable; and (b) know about *all* cache blocks, i.e. also of the FS primary caches and not just the blocks that spill into the secondary one. This changes the interface and VM data structures. This change is only for the interface (libminixfs) and VM data structures; the filesystem code is unmodified, so although the secondary cache will be used as normal, blocks will not be annotated with inode information until the FS is modified to provide this information. Until it is modified, mmap of files will fail gracefully on such filesystems. This is indicated to VFS/VM by returning ENOSYS for REQ_PEEK. Change-Id: I1d2df6c485e6c5e89eb28d9055076cc02629594e
2013-03-20 20:18:52 +01:00
struct phys_region *ph, int write, vfs_callback_t cb, void *s, int l)
VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
{
panic("anon_contig_pagefault: pagefault cannot happen");
}
static int anon_contig_new(struct vir_region *region)
{
u32_t allocflags;
phys_bytes new_pages, new_page_cl, cur_ph;
int p, pages;
allocflags = vrallocflags(region->flags);
pages = region->length/VM_PAGE_SIZE;
assert(physregions(region) == 0);
for(p = 0; p < pages; p++) {
struct phys_block *pb = pb_new(MAP_NONE);
struct phys_region *pr = NULL;
if(pb)
vm: new secondary cache code Primary purpose of change: to support the mmap implementation, VM must know both (a) about some block metadata for FS cache blocks, i.e. inode numbers and inode offsets where applicable; and (b) know about *all* cache blocks, i.e. also of the FS primary caches and not just the blocks that spill into the secondary one. This changes the interface and VM data structures. This change is only for the interface (libminixfs) and VM data structures; the filesystem code is unmodified, so although the secondary cache will be used as normal, blocks will not be annotated with inode information until the FS is modified to provide this information. Until it is modified, mmap of files will fail gracefully on such filesystems. This is indicated to VFS/VM by returning ENOSYS for REQ_PEEK. Change-Id: I1d2df6c485e6c5e89eb28d9055076cc02629594e
2013-03-20 20:18:52 +01:00
pr = pb_reference(pb, p * VM_PAGE_SIZE, region, &mem_type_anon_contig);
VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
if(!pr) {
if(pb) pb_free(pb);
map_free(region);
return ENOMEM;
}
}
assert(physregions(region) == pages);
if((new_page_cl = alloc_mem(pages, allocflags)) == NO_MEM) {
map_free(region);
return ENOMEM;
}
cur_ph = new_pages = CLICK2ABS(new_page_cl);
for(p = 0; p < pages; p++) {
vm: replace phys avl by array . make vm be able to use malloc() by overriding brk() and minix_mmap() functions . phys regions can then be malloc()ed and free()d instead of being in an avl tree, which is slightly faster . 'offset' field in phys_region can go too (offset is implied by position in array) but leads to bigger code changes
2012-12-17 19:26:52 +01:00
struct phys_region *pr = physblock_get(region, p * VM_PAGE_SIZE);
VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
assert(pr);
assert(pr->ph);
assert(pr->ph->phys == MAP_NONE);
assert(pr->offset == p * VM_PAGE_SIZE);
pr->ph->phys = cur_ph + pr->offset;
}
return OK;
}
static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l)
{
printf("VM: cannot resize physically contiguous memory.\n");
return ENOMEM;
}
vm: new secondary cache code Primary purpose of change: to support the mmap implementation, VM must know both (a) about some block metadata for FS cache blocks, i.e. inode numbers and inode offsets where applicable; and (b) know about *all* cache blocks, i.e. also of the FS primary caches and not just the blocks that spill into the secondary one. This changes the interface and VM data structures. This change is only for the interface (libminixfs) and VM data structures; the filesystem code is unmodified, so although the secondary cache will be used as normal, blocks will not be annotated with inode information until the FS is modified to provide this information. Until it is modified, mmap of files will fail gracefully on such filesystems. This is indicated to VFS/VM by returning ENOSYS for REQ_PEEK. Change-Id: I1d2df6c485e6c5e89eb28d9055076cc02629594e
2013-03-20 20:18:52 +01:00
static int anon_contig_reference(struct phys_region *pr,
struct phys_region *newpr)
VM: make mapping types explicit Introduce explicit abstractions for different mapping types, handling the instantiation, forking, pagefaults and freeing of anonymous memory, direct physical mappings, shared memory and physically contiguous anonymous memory as separate types, making region.c more generic. Also some other genericification like merging the 3 munmap cases into one. COW and SMAP safemap code is still implicit in region.c.
2012-10-11 15:15:49 +02:00
{
printf("VM: cannot fork with physically contig memory.\n");
return ENOMEM;
}
/* Methods inherited from the anonymous memory methods. */
static int anon_contig_unreference(struct phys_region *pr)
{
return mem_type_anon.ev_unreference(pr);
}
static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line)
{
return mem_type_anon.ev_sanitycheck(pr, file, line);
}
static int anon_contig_writable(struct phys_region *pr)
{
return mem_type_anon.writable(pr);
}
Reference in a new issue Copy permalink