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authorFreya Murphy <freya@freyacat.org>2024-01-29 13:22:50 -0500
committerFreya Murphy <freya@freyacat.org>2024-01-29 13:22:50 -0500
commite71a141533c742d05c0612d3a87ffb3810a4b5de (patch)
tree06f8b5f8d33b287e8443caa65dea4abb64a5d3c4 /src/memory/virtalloc.c
parentchanges (diff)
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memory works
Diffstat (limited to 'src/memory/virtalloc.c')
-rw-r--r--src/memory/virtalloc.c18
1 files changed, 12 insertions, 6 deletions
diff --git a/src/memory/virtalloc.c b/src/memory/virtalloc.c
index b8135ef..f8d8169 100644
--- a/src/memory/virtalloc.c
+++ b/src/memory/virtalloc.c
@@ -26,7 +26,7 @@ static struct addr_node *alloc_node(void) {
} else {
struct addr_node *node = &nodes[bss_nodes];
bss_nodes += 1;
- node->is_bss = false;
+ node->is_bss = true;
return node;
}
return NULL;
@@ -39,8 +39,8 @@ static void free_node(struct addr_node *node) {
void virtaddr_init(void) {
struct addr_node init = {
- .start = 0,
- .end = UINT64_MAX,
+ .start = 0x400000, // third page table
+ .end = 0x1000000000000, // 48bit memory address max
.next = NULL,
.prev = NULL,
.is_alloc = false,
@@ -53,6 +53,10 @@ void virtaddr_init(void) {
void *virtaddr_alloc(int n_pages) {
+
+ if (n_pages < 1)
+ return NULL;
+
long n_length = n_pages * PAGE_SIZE;
struct addr_node *node = start_node;
@@ -64,17 +68,19 @@ void *virtaddr_alloc(int n_pages) {
long length = node->end - node->start;
if (length >= n_length) {
struct addr_node *new = alloc_node();
- if (node == NULL)
+ if (node == NULL) {
return NULL;
- new->next = node;
- node->prev = new;
+ }
if (node->prev != NULL) {
node->prev->next = new;
}
+ new->next = node;
+ node->prev = new;
new->start = node->start;
new->end = new->start + n_length;
node->start = new->end;
new->is_alloc = true;
+ new->next = node;
return (void *) new->start;
}
}