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Diffstat (limited to 'kalloc.c')
-rw-r--r--kalloc.c58
1 files changed, 20 insertions, 38 deletions
diff --git a/kalloc.c b/kalloc.c
index fb939b7..c943e5e 100644
--- a/kalloc.c
+++ b/kalloc.c
@@ -3,13 +3,14 @@
// and pipe buffers. Allocates 4096-byte pages.
#include "types.h"
-#include "defs.h"
#include "param.h"
#include "memlayout.h"
-#include "mmu.h"
#include "spinlock.h"
+#include "riscv.h"
+#include "defs.h"
+
+void freerange(void *pa_start, void *pa_end);
-void freerange(void *vstart, void *vend);
extern char end[]; // first address after kernel loaded from ELF file
// defined by the kernel linker script in kernel.ld
@@ -19,36 +20,22 @@ struct run {
struct {
struct spinlock lock;
- int use_lock;
struct run *freelist;
} kmem;
-// Initialization happens in two phases.
-// 1. main() calls kinit1() while still using entrypgdir to place just
-// the pages mapped by entrypgdir on free list.
-// 2. main() calls kinit2() with the rest of the physical pages
-// after installing a full page table that maps them on all cores.
void
-kinit1(void *vstart, void *vend)
+kinit()
{
initlock(&kmem.lock, "kmem");
- kmem.use_lock = 0;
- freerange(vstart, vend);
-}
-
-void
-kinit2(void *vstart, void *vend)
-{
- freerange(vstart, vend);
- kmem.use_lock = 1;
+ freerange(end, (void*)PHYSTOP);
}
void
-freerange(void *vstart, void *vend)
+freerange(void *pa_start, void *pa_end)
{
char *p;
- p = (char*)PGROUNDUP((uint64)vstart);
- for(; p + PGSIZE <= (char*)vend; p += PGSIZE)
+ p = (char*)PGROUNDUP((uint64)pa_start);
+ for(; p + PGSIZE <= (char*)pa_end; p += PGSIZE)
kfree(p);
}
//PAGEBREAK: 21
@@ -57,42 +44,37 @@ freerange(void *vstart, void *vend)
// call to kalloc(). (The exception is when
// initializing the allocator; see kinit above.)
void
-kfree(char *v)
+kfree(void *pa)
{
struct run *r;
- if((uint64)v % PGSIZE || v < end || V2P(v) >= PHYSTOP)
+ if(((uint64)pa % PGSIZE) != 0 || (char*)pa < end || (uint64)pa >= PHYSTOP)
panic("kfree");
// Fill with junk to catch dangling refs.
- memset(v, 1, PGSIZE);
+ memset(pa, 1, PGSIZE);
- if(kmem.use_lock)
- acquire(&kmem.lock);
- r = (struct run*)v;
+ acquire(&kmem.lock);
+ r = (struct run*)pa;
r->next = kmem.freelist;
kmem.freelist = r;
- if(kmem.use_lock)
- release(&kmem.lock);
+ release(&kmem.lock);
}
// Allocate one 4096-byte page of physical memory.
// Returns a pointer that the kernel can use.
// Returns 0 if the memory cannot be allocated.
-char*
+void *
kalloc(void)
{
struct run *r;
- if(kmem.use_lock)
- acquire(&kmem.lock);
+ acquire(&kmem.lock);
r = kmem.freelist;
if(r)
kmem.freelist = r->next;
- if(kmem.use_lock)
- release(&kmem.lock);
- if(r != 0 && (uint64) r < KERNBASE)
- panic("kalloc");
- return (char*)r;
+ release(&kmem.lock);
+ memset((char*)r, 5, PGSIZE); // fill with junk
+ return (void*)r;
}