add generic kremap for kernel remapping

[lunaix-os.git] / lunaix-os / arch / generic / kremap.c

diff --git a/lunaix-os/arch/generic/kremap.c b/lunaix-os/arch/generic/kremap.c
new file mode 100644 (file)
index 0000000..3cd6fa7
--- /dev/null
+++ b/lunaix-os/arch/generic/kremap.c
@@ -0,0 +1,147 @@
+#include <lunaix/mm/pagetable.h>
+#include <lunaix/sections.h>
+
+#include <asm/boot_stage.h>
+#include <asm/mm_defs.h>
+#include <asm-generic/init_pagetable.h>
+
+ptr_t boot_text
+kpt_alloc_table(struct pt_alloc* alloc)
+{
+    if (alloc->index >= alloc->total) {
+        return 0;
+    }
+
+    ptr_t next;
+
+    next = alloc->base + alloc->index * PAGE_SIZE;
+    alloc->index++;
+
+    return next;
+}
+
+static bool boot_text
+__walk(struct ptw_state* state, ptr_t addr, 
+       unsigned long level_size, bool create)
+{
+    pte_t pte, *pt;
+    int level, pt_index;
+    unsigned long lsize;
+    ptr_t  next_level;
+
+    pt = state->root;
+    level = 0;
+
+    do {
+        lsize    = lnt_page_size(level);
+        pt_index = va_level_index(addr, lsize);
+
+        pte = pt[pt_index];
+        if (!pte_isnull(pte)) {
+            next_level = pte_paddr(pte);
+            goto cont;
+        }
+
+        if (pt_last_level(level) || lsize == level_size) {
+            break;
+        }
+
+        if (!create) {
+            goto fail;
+        }
+
+        next_level = kpt_alloc_table(state->alloc);
+        if (!next_level) {
+            state->lntp = NULL;
+            goto fail;
+        }
+
+        pte = mkpte(next_level, KERNEL_PGTAB);
+        pt[pt_index] = pte;
+
+    cont:
+        pt = (pte_t*) next_level;
+        level++;
+    }
+    while (lsize > level_size);
+
+    state->lntp  = pt;
+    state->level = level;
+    state->tab_index = pt_index;
+
+    return true;
+
+fail:
+    state->lntp = NULL;
+    return false;
+}
+
+unsigned int boot_text
+kpt_set_ptes_flatten(struct ptw_state* state, ptr_t addr, 
+                pte_t pte, unsigned long lsize, unsigned int nr)
+{
+    unsigned int tab_i, _n;
+    pte_t *lntp;
+
+    _n = 0;
+    addr = addr & ~(lsize - 1);
+
+    do {
+        if (!__walk(state, addr, lsize, true)) {
+            break;
+        }
+
+        lntp  = state->lntp;
+        tab_i = state->tab_index;
+        while (_n < nr && tab_i < LEVEL_SIZE) {
+            lntp[tab_i++] = pte;
+            pte = pte_advance(pte, lsize);
+
+            addr += lsize;
+            _n++;
+        }
+    }
+    while (_n < nr);
+
+    return _n;
+}
+
+#define ksection_maps autogen_name(ksecmap)
+#define PF_X 0x1
+#define PF_W 0x2
+
+extern_autogen(ksecmap);
+
+bridge_farsym(__kexec_text_start);
+bridge_farsym(ksection_maps);
+
+void boot_text
+kpt_migrate_highmem(struct ptw_state* state)
+{
+    pte_t pte;
+    struct ksecmap* maps;
+    struct ksection* section;
+    pfn_t pgs;
+
+    maps = (struct ksecmap*)to_kphysical(__far(ksection_maps));
+
+    for (unsigned int i = 0; i < maps->num; i++)
+    {
+        section = &maps->secs[i];
+        
+        if (section->va < KERNEL_RESIDENT) {
+            continue;
+        }
+
+        pte = mkpte(section->pa, KERNEL_RDONLY);
+        if ((section->flags & PF_X)) {
+            pte = pte_mkexec(pte);
+        }
+        if ((section->flags & PF_W)) {
+            pte = pte_mkwritable(pte);
+        }
+
+        pgs = leaf_count(section->size);
+        kpt_set_ptes(state, section->va, pte, LFT_SIZE, pgs);
+    }
+}
\ No newline at end of file