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minix/servers/vm/mem_anon_contig.c

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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,
Implement getrusage Implement getrusage. These fields of struct rusage are not supported and always set to zero at this time long ru_nswap; /* swaps */ long ru_inblock; /* block input operations */ long ru_oublock; /* block output operations */ long ru_msgsnd; /* messages sent */ long ru_msgrcv; /* messages received */ long ru_nvcsw; /* voluntary context switches */ long ru_nivcsw; /* involuntary context switches */ test75.c is the unit test for this new function Change-Id: I3f1eb69de1fce90d087d76773b09021fc6106539
2013-06-25 14:41:01 +02:00
struct phys_region *ph, int write, vfs_callback_t cb, void *state,
int len, int *io);
make vfs & filesystems use failable copying Change the kernel to add features to vircopy and safecopies so that transparent copy fixing won't happen to avoid deadlocks, and such copies fail with EFAULT. Transparently making copying work from filesystems (as normally done by the kernel & VM when copying fails because of missing/readonly memory) is problematic as it can happen that, for file-mapped ranges, that that same filesystem that is blocked on the copy request is needed to satisfy the memory range, leading to deadlock. Dito for VFS itself, if done with a blocking call. This change makes the copying done from a filesystem fail in such cases with EFAULT by VFS adding the CPF_TRY flag to the grants. If a FS call fails with EFAULT, VFS will then request the range to be made available to VM after the FS is unblocked, allowing it to be used to satisfy the range if need be in another VFS thread. Similarly, for datacopies that VFS itself does, it uses the failable vircopy variant and callers use a wrapper that talk to VM if necessary to get the copy to work. . kernel: add CPF_TRY flag to safecopies . kernel: only request writable ranges to VM for the target buffer when copying fails . do copying in VFS TRY-first . some fixes in VM to build SANITYCHECK mode . add regression test for the cases where - a FS system call needs memory mapped in a process that the FS itself must map. - such a range covers more than one file-mapped region. . add 'try' mode to vircopy, physcopy . add flags field to copy kernel call messages . if CP_FLAG_TRY is set, do not transparently try to fix memory ranges . for use by VFS when accessing user buffers to avoid deadlock . remove some obsolete backwards compatability assignments . VFS: let thread scheduling work for VM requests too Allows VFS to make calls to VM while suspending and resuming the currently running thread. Does currently not work for the main thread. . VM: add fix memory range call for use by VFS Change-Id: I295794269cea51a3163519a9cfe5901301d90b32
2014-01-16 14:22:13 +01:00
static int anon_contig_sanitycheck(struct phys_region *pr, const char *file, int line);
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_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);
arm:vm allow per memory type flags. Change-Id: Id5a5bd479bdfbbc3fb52a85c29e1d7712a1171a7
2013-09-25 10:41:26 +02:00
static int anon_contig_pt_flags(struct vir_region *vr);
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
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,
arm:vm allow per memory type flags. Change-Id: Id5a5bd479bdfbbc3fb52a85c29e1d7712a1171a7
2013-09-25 10:41:26 +02:00
.writable = anon_contig_writable,
.pt_flags = anon_contig_pt_flags,
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
};
arm:vm allow per memory type flags. Change-Id: Id5a5bd479bdfbbc3fb52a85c29e1d7712a1171a7
2013-09-25 10:41:26 +02:00
static int anon_contig_pt_flags(struct vir_region *vr){
#if defined(__arm__)
return ARM_VM_PTE_DEVICE;
#else
return 0;
#endif
}
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_pagefault(struct vmproc *vmp, struct vir_region *region,
Implement getrusage Implement getrusage. These fields of struct rusage are not supported and always set to zero at this time long ru_nswap; /* swaps */ long ru_inblock; /* block input operations */ long ru_oublock; /* block output operations */ long ru_msgsnd; /* messages sent */ long ru_msgrcv; /* messages received */ long ru_nvcsw; /* voluntary context switches */ long ru_nivcsw; /* involuntary context switches */ test75.c is the unit test for this new function Change-Id: I3f1eb69de1fce90d087d76773b09021fc6106539
2013-06-25 14:41:01 +02:00
struct phys_region *ph, int write, vfs_callback_t cb, void *state,
int len, int *io)
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;
vm: make WARNS=5 proof Change-Id: I737ded223daf04f1c0c85a2e8e6b36c8fdcd07db
2013-08-20 14:02:33 +02:00
phys_bytes p, pages;
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
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);
}
make vfs & filesystems use failable copying Change the kernel to add features to vircopy and safecopies so that transparent copy fixing won't happen to avoid deadlocks, and such copies fail with EFAULT. Transparently making copying work from filesystems (as normally done by the kernel & VM when copying fails because of missing/readonly memory) is problematic as it can happen that, for file-mapped ranges, that that same filesystem that is blocked on the copy request is needed to satisfy the memory range, leading to deadlock. Dito for VFS itself, if done with a blocking call. This change makes the copying done from a filesystem fail in such cases with EFAULT by VFS adding the CPF_TRY flag to the grants. If a FS call fails with EFAULT, VFS will then request the range to be made available to VM after the FS is unblocked, allowing it to be used to satisfy the range if need be in another VFS thread. Similarly, for datacopies that VFS itself does, it uses the failable vircopy variant and callers use a wrapper that talk to VM if necessary to get the copy to work. . kernel: add CPF_TRY flag to safecopies . kernel: only request writable ranges to VM for the target buffer when copying fails . do copying in VFS TRY-first . some fixes in VM to build SANITYCHECK mode . add regression test for the cases where - a FS system call needs memory mapped in a process that the FS itself must map. - such a range covers more than one file-mapped region. . add 'try' mode to vircopy, physcopy . add flags field to copy kernel call messages . if CP_FLAG_TRY is set, do not transparently try to fix memory ranges . for use by VFS when accessing user buffers to avoid deadlock . remove some obsolete backwards compatability assignments . VFS: let thread scheduling work for VM requests too Allows VFS to make calls to VM while suspending and resuming the currently running thread. Does currently not work for the main thread. . VM: add fix memory range call for use by VFS Change-Id: I295794269cea51a3163519a9cfe5901301d90b32
2014-01-16 14:22:13 +01:00
static int anon_contig_sanitycheck(struct phys_region *pr, const char *file, int line)
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
{
return mem_type_anon.ev_sanitycheck(pr, file, line);
}
static int anon_contig_writable(struct phys_region *pr)
{
return mem_type_anon.writable(pr);
}
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