Implement lock IRQ nesting via stack variables/contexts

kernel/mm/pmm.c

@@ -100,6 +100,8 @@ static size_t pmm_find_free_space (struct pmm_region* pmm_region, size_t nblks)
 }
 
 physaddr_t pmm_alloc (size_t nblks) {
+  spin_lock_ctx_t ctxpmmr;
+
   for (size_t region = 0; region < PMM_REGIONS_MAX; region++) {
     struct pmm_region* pmm_region = &pmm.regions[region];
 
@@ -107,7 +109,7 @@ physaddr_t pmm_alloc (size_t nblks) {
     if (!(pmm_region->flags & PMM_REGION_ACTIVE))
       continue;
 
-    spin_lock (&pmm_region->lock);
+    spin_lock (&pmm_region->lock, &ctxpmmr);
 
     /* Find starting bit of the free bit range */
     size_t bit = pmm_find_free_space (pmm_region, nblks);
@@ -116,18 +118,19 @@ physaddr_t pmm_alloc (size_t nblks) {
     if (bit != (size_t)-1) {
       /* Mark it */
       bm_set_region (&pmm_region->bm, bit, nblks);
-      spin_unlock (&pmm_region->lock);
+      spin_unlock (&pmm_region->lock, &ctxpmmr);
 
       return pmm_region->membase + bit * PAGE_SIZE;
     }
 
-    spin_unlock (&pmm_region->lock);
+    spin_unlock (&pmm_region->lock, &ctxpmmr);
   }
 
   return PMM_ALLOC_ERR;
 }
 
 void pmm_free (physaddr_t p_addr, size_t nblks) {
+  spin_lock_ctx_t ctxpmmr;
   /* Round down to nearest page boundary */
   physaddr_t aligned_p_addr = align_down (p_addr, PAGE_SIZE);
 
@@ -145,11 +148,11 @@ void pmm_free (physaddr_t p_addr, size_t nblks) {
 
       size_t bit = div_align_up (addr, PAGE_SIZE);
 
-      spin_lock (&pmm_region->lock);
+      spin_lock (&pmm_region->lock, &ctxpmmr);
 
       bm_clear_region (&pmm_region->bm, bit, nblks);
 
-      spin_unlock (&pmm_region->lock);
+      spin_unlock (&pmm_region->lock, &ctxpmmr);
 
       break;
     }