Adding code

6 files changed, 39 insertions, 0 deletions

diff --git a/include/09.paging/paging00.c b/include/09.paging/paging00.c
new file mode 100644
index 0000000..c45e28b
--- /dev/null
+++ b/include/09.paging/paging00.c
@@ -0,0 +1 @@
+#include<types.h>
diff --git a/include/09.paging/paging01.c b/include/09.paging/paging01.c
new file mode 100644
index 0000000..0789338
--- /dev/null
+++ b/include/09.paging/paging01.c
@@ -0,0 +1,3 @@
+extern void loadPageDirectory(uint32_t*);
+extern void enablePaging();
+uint32_t page_directory[1024] __attribute__((aligned(4096)));
diff --git a/include/09.paging/paging02.c b/include/09.paging/paging02.c
new file mode 100644
index 0000000..8c00c89
--- /dev/null
+++ b/include/09.paging/paging02.c
@@ -0,0 +1,12 @@
+void set_pd()
+{
+    //set each entry to not present
+    for(size_t i=0;i<1024;i++)
+    {
+	// This sets the following flags to the pages:
+	//   Supervisor: Only kernel-mode can access them
+	//   Write Enabled: It can be both read from and written to
+	//   Not Present: The page table is not present
+	page_directory[i] = 0x00000002;
+    }
+}
diff --git a/include/09.paging/paging03.c b/include/09.paging/paging03.c
new file mode 100644
index 0000000..57f997d
--- /dev/null
+++ b/include/09.paging/paging03.c
@@ -0,0 +1 @@
+uint32_t page_table[1024][1024] __attribute__((aligned(4096)));
diff --git a/include/09.paging/paging04.c b/include/09.paging/paging04.c
new file mode 100644
index 0000000..ad7507f
--- /dev/null
+++ b/include/09.paging/paging04.c
@@ -0,0 +1,15 @@
+void set_pt(size_t num,uint32_t address)
+{
+    // holds the physical address where we want to start mapping these pages to.
+    // in this case, we want to map these pages to the very beginning of memory.
+    //we will fill all 1024 entries in the table, mapping 4 megabytes
+    for(size_t i=0;i<1024;i++)
+    {
+	// As the address is page aligned, it will always leave 12 bits zeroed.
+	// Those bits are used by the attributes ;)
+	page_table[num][i] = (address + i * 0x1000) | 3; // attributes: supervisor level, read/write, present.
+    }
+
+    page_directory[num] = ((uint32_t)page_table[num]) | 3;
+    // attributes: supervisor level, read/write, present
+}
diff --git a/include/09.paging/paging05.c b/include/09.paging/paging05.c
new file mode 100644
index 0000000..d99797b
--- /dev/null
+++ b/include/09.paging/paging05.c
@@ -0,0 +1,7 @@
+void set_paging()
+{
+    set_pd();
+    for(size_t i=0;i<1024;i++) set_pt(i,0x00400000 * i); // all 4GB mapped
+    loadPageDirectory(page_directory);
+    enablePaging();
+}