own virtual address space for stack

1 files changed, 75 insertions, 3 deletions

diff --git a/kernel/vmem.c b/kernel/vmem.c
index a582991..5dccc13 100644
--- a/kernel/vmem.c
+++ b/kernel/vmem.c
@@ -185,7 +185,6 @@ void vmem_free_dir(pdirectory *dir)
     }
 
     // programm space 
-    
     virt_addr=0x8000000;
     for(int j=0;j<2;j++)
     {
@@ -204,13 +203,36 @@ void vmem_free_dir(pdirectory *dir)
 
     }
 
+    // stack
+    virt_addr=0x8c00000;
+    for(int j=0;j<1;j++)
+    {
+
+	pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
+	ptable *table=pd_entry_get_frame(entry);
+    
+	for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096) 
+	{
+	    pt_entry pte=&table->m_entries [PAGE_TABLE_INDEX (virt) ];
+	    pmmngr_free_block(pt_entry_get_frame(pte));   // get free space from the memory manager
+	}
+
+	pmmngr_free_block(pd_entry_get_frame (entry));
+	virt_addr+=1024*4096;
+
+    }
     pmmngr_free_block(dir);
 
     x86_paging_enable();
 }
 
 // vmem init and also copies all the shit for FORK 
-// for now it allocates always 2 * 1024 * 4096 bytes at
+// for now it allocates always 3 * 1024 * 4096 bytes at for the kernel
+//  virtual / physical 0x0-0xc00000 (~12MB)
+//  2*1024*4096 for the loaded prog
+//  virtual 0x8000000-0x8800000 (~8MB)
+//  and 1*1024*4096 for the loaded programms stack
+//  0x8c00000-0x9000000 (~4MB)
 //
 pdirectory* vmem_new_space_dir(pdirectory *copy_dir)
 {
@@ -321,7 +343,57 @@ pdirectory* vmem_new_space_dir(pdirectory *copy_dir)
 	virt_addr+=1024*4096;
 
     }
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_DEBUG,"last addr (0x%08X,0x%08X)",phys_addr, virt_addr);
+
+    // programm space 
+    virt_addr=0x8c00000;
+    for(int j=0;j<1;j++)
+    {
+
+	ptable* table = (ptable*) pmmngr_alloc_block ();
+	pd_entry *oldentry= &(copy_dir->m_entries[PAGE_DIRECTORY_INDEX(virt_addr)]);
+	ptable* oldtable=pd_entry_get_frame(oldentry);
+	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_DEBUG,"oldtable at: 0x%08X",oldtable);
+
+	if (!table)panic(FOOLOS_MODULE_NAME,"unable to alloc table");
+	log(FOOLOS_MODULE_NAME,FOOLOS_LOG_DEBUG,"alloc table: %08X",table);
+    
+	for (int i=0, virt=virt_addr; i<1024; i++, virt+=4096) 
+	{
+	    phys_addr=pmmngr_alloc_block();   // get free space from the memory manager
+	    if (!phys_addr)panic(FOOLOS_MODULE_NAME,"unable to alloc spce for frame");
+
+	    // if this is not init , copy contents from current space!
+	    if(copy_dir!=NULL)
+	    {
+		uint32_t addr_old=pt_entry_get_frame(&oldtable->m_entries[PAGE_TABLE_INDEX(virt)]);
+		log(FOOLOS_MODULE_NAME,FOOLOS_LOG_FINE,"physical memcpy(0x%08X,0x%08X,4096)",phys_addr, addr_old);
+		memcpy(phys_addr,addr_old,4096);
+
+	    }
+
+	    uint32_t frame=phys_addr;
+
+	    //! create a new page
+	    pt_entry page=0;
+	    pt_entry_add_attrib (&page, I86_PTE_PRESENT);
+	    pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
+	    pt_entry_set_frame (&page, frame);
+
+
+	    //! ...and add it to the page table
+	    table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
+
+	}
+	
+	pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt_addr) ];
+	*entry=0;
+	pd_entry_add_attrib (entry, I86_PDE_PRESENT);
+	pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
+	pd_entry_set_frame (entry, (physical_addr)table);
+
+	virt_addr+=1024*4096;
+
+    }
 
     if(copy_dir!=NULL)x86_paging_enable();