aboutsummaryrefslogtreecommitdiff
path: root/kernel/mm/virtual_mm/virtual_mm.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/mm/virtual_mm/virtual_mm.c')
-rw-r--r--kernel/mm/virtual_mm/virtual_mm.c45
1 files changed, 21 insertions, 24 deletions
diff --git a/kernel/mm/virtual_mm/virtual_mm.c b/kernel/mm/virtual_mm/virtual_mm.c
index 4153065..573767e 100644
--- a/kernel/mm/virtual_mm/virtual_mm.c
+++ b/kernel/mm/virtual_mm/virtual_mm.c
@@ -135,54 +135,51 @@ get_or_make_table(uint32_t *pd_entry)
return table;
}
-ALWAYS_INLINE void
+uint32_t
virtual_mm_find_free_virtual_addresses(uint32_t n)
{
/* Skip the first page directory, we don't wanna touch the first 4MiB. */
- for (uint32_t i = 1; i < PAGE_DIRECTORY_SIZE; i++) {
- uint32_t *pd_entry = &current_page_directory[i];
+ for (uint32_t pd_index = 1; pd_index < PAGE_DIRECTORY_SIZE; pd_index++) {
+ uint32_t starting_pd_index = pd_index;
+ uint32_t *pd_entry = &current_page_directory[pd_index];
uint32_t *table = get_or_make_table(pd_entry);
- for (uint32_t j = 0; j < PAGE_TABLE_SIZE; j++) {
- uint32_t *pt_entry = &table[j];
+ for (uint32_t starting_pt_index = 0; starting_pt_index < PAGE_TABLE_SIZE;
+ starting_pt_index++) {
+ uint32_t *pt_entry = &table[starting_pt_index];
if (PTE_IS_PRESENT(pt_entry))
continue;
/* We found our starting pt_entry */
- printk("debug", "Starting: 0x%x", pt_entry);
uint32_t count = 0;
- for (uint32_t k = j; k <= PAGE_TABLE_SIZE; k++) {
+ for (uint32_t pt_index = starting_pt_index; pt_index <= PAGE_TABLE_SIZE;
+ pt_index++) {
/* If we overflow, switch to the consecutive page directory entry */
- if (k == PAGE_TABLE_SIZE) {
- if (++i == PAGE_DIRECTORY_SIZE)
- ASSERT_NOT_REACHED(); /* Ran out of pd_entries */
-
- pd_entry = &current_page_directory[i];
- printk("debug", "Switching pd_entry: 0x%x", pd_entry);
+ if (pt_index == PAGE_TABLE_SIZE) {
+ if (++pd_index == PAGE_DIRECTORY_SIZE)
+ return 0; /* Ran out of pd_entries */
+ pd_entry = &current_page_directory[pd_index];
table = get_or_make_table(pd_entry);
- k = 0;
+ pt_index = 0;
}
/* If page table entry is already used, break from the current loop */
- uint32_t *pt_entry = &table[k];
+ uint32_t *pt_entry = &table[pt_index];
if (PTE_IS_PRESENT(pt_entry)) {
/* Since we have some used address at some point between j and count,
* we can't find n consecutive free addresses in between j and the
* used block (j + count + 1) */
- j += count;
+ starting_pt_index += count;
break;
}
- // printk("debug", "Found page: 0x%x", &table[k]);
- count++;
- if (count == n) {
- /* TODO: Convert this into a virtual_address using the pd_index &
- * pt_index */
- printk("debug", "Found starting page at: 0x%x", &table[j]);
- return;
- }
+ if (++count == n)
+ return VIRTUAL_ADDRESS(starting_pd_index, starting_pt_index);
}
}
}
+
+ ASSERT_NOT_REACHED();
+ return 0;
}