Added support for fixing faults on physical memory.

1 files changed, 33 insertions, 3 deletions

diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c
index 187456b..642b144 100644
--- a/arch/um/kernel/trap_kern.c
+++ b/arch/um/kernel/trap_kern.c
@@ -21,6 +21,8 @@
 #include "chan_kern.h"
 #include "mconsole_kern.h"
 #include "2_5compat.h"
+#include "mem.h"
+#include "mem_kern.h"
 
 unsigned long handle_page_fault(unsigned long address, unsigned long ip, 
 				int is_write, int is_user, int *code_out)
@@ -85,6 +87,33 @@ unsigned long handle_page_fault(unsigned long address, unsigned long ip,
 	return(handled);
 }
 
+LIST_HEAD(physmem_remappers);
+
+void register_remapper(struct remapper *info)
+{
+	list_add(&info->list, &physmem_remappers);
+}
+
+static int check_remapped_addr(unsigned long address, int is_write)
+{
+	struct remapper *remapper;
+	struct list_head *ele;
+	__u64 offset;
+	int fd;
+
+	fd = phys_mapping(__pa(address), &offset);
+	if(fd == -1)
+		return(0);
+
+	list_for_each(ele, &physmem_remappers){
+		remapper = list_entry(ele, struct remapper, list);
+		if((*remapper->proc)(fd, address, is_write, offset))
+			return(1);
+	}
+
+	return(0);
+}
+
 unsigned long segv(unsigned long address, unsigned long ip, int is_write, 
 		   int is_user, void *sc)
 {
@@ -96,7 +125,9 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write,
                 flush_tlb_kernel_vm();
                 return(0);
         }
-        if(current->mm == NULL)
+	else if(check_remapped_addr(address & PAGE_MASK, is_write))
+		return(0);
+	else if(current->mm == NULL)
 		panic("Segfault with no mm");
 
 	handled = handle_page_fault(address, ip, is_write, is_user, 
@@ -109,9 +140,8 @@ unsigned long segv(unsigned long address, unsigned long ip, int is_write,
 		current->thread.fault_addr = (void *) address;
 		do_longjmp(catcher, 1);
 	} 
-	else if(current->thread.fault_addr != NULL){
+	else if(current->thread.fault_addr != NULL)
 		panic("fault_addr set but no fault catcher");
-	}
 	else if(arch_fixup(ip, sc))
 		return(0);