xref: /minix/minix/servers/vm/mem_anon_contig.c (revision 9f988b79)
1 
2 /* This file implements the methods of physically contiguous anonymous memory. */
3 
4 #include <assert.h>
5 
6 #include "proto.h"
7 #include "vm.h"
8 #include "region.h"
9 #include "glo.h"
10 
11 static int anon_contig_reference(struct phys_region *, struct phys_region *);
12 static int anon_contig_unreference(struct phys_region *pr);
13 static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
14 	struct phys_region *ph, int write, vfs_callback_t cb, void *state,
15 	int len, int *io);
16 static int anon_contig_sanitycheck(struct phys_region *pr, const char *file, int line);
17 static int anon_contig_writable(struct phys_region *pr);
18 static void anon_contig_split(struct vmproc *vmp, struct vir_region *vr,
19                         struct vir_region *r1, struct vir_region *r2);
20 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l);
21 static int anon_contig_new(struct vir_region *vr);
22 static int anon_contig_pt_flags(struct vir_region *vr);
23 
24 struct mem_type mem_type_anon_contig = {
25 	.name = "anonymous memory (physically contiguous)",
26 	.ev_new = anon_contig_new,
27 	.ev_reference = anon_contig_reference,
28 	.ev_unreference = anon_contig_unreference,
29 	.ev_pagefault = anon_contig_pagefault,
30 	.ev_resize = anon_contig_resize,
31 	.ev_split = anon_contig_split,
32 	.ev_sanitycheck = anon_contig_sanitycheck,
33 	.writable = anon_contig_writable,
34 	.pt_flags = anon_contig_pt_flags,
35 };
36 
37 static int anon_contig_pt_flags(struct vir_region *vr){
38 #if defined(__arm__)
39 	return  ARM_VM_PTE_DEVICE;
40 #else
41 	return  0;
42 #endif
43 }
44 
45 static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
46 	struct phys_region *ph, int write, vfs_callback_t cb, void *state,
47 	int len, int *io)
48 {
49 	panic("anon_contig_pagefault: pagefault cannot happen");
50 }
51 
52 static int anon_contig_new(struct vir_region *region)
53 {
54         u32_t allocflags;
55 	phys_bytes new_pages, new_page_cl, cur_ph;
56 	phys_bytes p, pages;
57 
58         allocflags = vrallocflags(region->flags);
59 
60 	pages = region->length/VM_PAGE_SIZE;
61 
62 	assert(physregions(region) == 0);
63 
64 	for(p = 0; p < pages; p++) {
65 		struct phys_block *pb = pb_new(MAP_NONE);
66 		struct phys_region *pr = NULL;
67 		if(pb)
68 			pr = pb_reference(pb, p * VM_PAGE_SIZE, region, &mem_type_anon_contig);
69 		if(!pr) {
70 			if(pb) pb_free(pb);
71 			map_free(region);
72 			return ENOMEM;
73 		}
74 	}
75 
76 	assert(physregions(region) == pages);
77 
78 	if((new_page_cl = alloc_mem(pages, allocflags)) == NO_MEM) {
79 		map_free(region);
80 		return ENOMEM;
81 	}
82 
83 	cur_ph = new_pages = CLICK2ABS(new_page_cl);
84 
85 	for(p = 0; p < pages; p++) {
86 		struct phys_region *pr = physblock_get(region, p * VM_PAGE_SIZE);
87 		assert(pr);
88 		assert(pr->ph);
89 		assert(pr->ph->phys == MAP_NONE);
90 		assert(pr->offset == p * VM_PAGE_SIZE);
91 		pr->ph->phys = cur_ph + pr->offset;
92 	}
93 
94 	return OK;
95 }
96 
97 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l)
98 {
99 	printf("VM: cannot resize physically contiguous memory.\n");
100 	return ENOMEM;
101 }
102 
103 static int anon_contig_reference(struct phys_region *pr,
104 	struct phys_region *newpr)
105 {
106 	printf("VM: cannot fork with physically contig memory.\n");
107 	return ENOMEM;
108 }
109 
110 /* Methods inherited from the anonymous memory methods. */
111 
112 static int anon_contig_unreference(struct phys_region *pr)
113 {
114 	return mem_type_anon.ev_unreference(pr);
115 }
116 
117 static int anon_contig_sanitycheck(struct phys_region *pr, const char *file, int line)
118 {
119 	return mem_type_anon.ev_sanitycheck(pr, file, line);
120 }
121 
122 static int anon_contig_writable(struct phys_region *pr)
123 {
124 	return mem_type_anon.writable(pr);
125 }
126 
127 static void anon_contig_split(struct vmproc *vmp, struct vir_region *vr,
128                         struct vir_region *r1, struct vir_region *r2)
129 {
130 	return;
131 }
132 
133