1 files changed, 146 insertions, 0 deletions
diff --git a/arch/x86_64/syscall/invoke-mapping.c b/arch/x86_64/syscall/invoke-mapping.c
new file mode 100644
index 0000000..be401d6
--- /dev/null
+++ b/arch/x86_64/syscall/invoke-mapping.c
@@ -0,0 +1,146 @@
+#include "arch/x86_64/syscall/wrappers.h"
+#include "arch/x86_64/syscall.h"
+#include "arch/x86_64/page.h"
+#include <stddef.h>
+#include "error.h"
+#include "lock.h"
+#include "string.h"
+#include "memory.h"
+#include "print.h"
+
+static int
+s_handle_invoke_mapping_exists(
+        objdir_t *root_dir, 
+        objdir_entry_t *target_entry, 
+        uint8_t *payload, 
+        size_t payload_at
+        )
+{
+    pmle_t *pml4 = (pmle_t*)vmem_phys_tovirt(target_entry->data);
+    pmle_t *target_pml;
+    uint8_t target_depth;
+    SYSCALL_PAYLOAD_TAKEPML(payload, payload_at, pml4, target_depth, target_pml);
+    if(target_pml == NULL || !target_pml->p) return KE_DNE;
+
+#ifdef DBG_SYSCALL
+    klogf("pml d%i %p from %p exists\n", target_depth, target_pml, pml4);
+#endif
+    return 0;
+}
+
+static int
+s_handle_invoke_mapping_map(
+        objdir_t *root_dir, 
+        objdir_entry_t *target_entry, 
+        uint8_t *payload, 
+        size_t payload_at
+        )
+{
+    pmle_t *pml4 = (pmle_t*)vmem_phys_tovirt(target_entry->data);
+    pmle_t *target_pml;
+    uint8_t target_depth;
+    SYSCALL_PAYLOAD_TAKEPML(payload, payload_at, pml4, target_depth, target_pml);
+    if(target_pml == NULL) return KE_DNE;
+
+    size_t untyped_pathw;
+    objdir_entry_t *untyped_entry;
+    SYSCALL_PAYLOAD_TAKEOBJ(payload, payload_at, untyped_pathw, untyped_entry);
+    
+    if(untyped_entry->type != KO_MEMORY_UNTYPED) return KE_BADOBJ;
+    mtx_acquire(&untyped_entry->lock);
+
+    if((untyped_entry->data & 0xFFF) != 0) {
+        mtx_release(&untyped_entry->lock);
+        return KE_ALIGN;
+    }
+
+    uintptr_t untyped_phys = untyped_entry->data;
+    size_t *untyped = ko_entry_data(untyped_entry);
+    size_t untyped_size = *untyped;
+    if(untyped_size != 0x1000) {
+        mtx_release(&untyped_entry->lock);
+        return KE_BADSIZE;
+    }
+    
+    target_pml->value = untyped_phys | PAGE_RW | PAGE_US | PAGE_PRESENT;
+    __asm__ volatile("invlpg (%0)":: "r"(untyped): "memory");
+
+    if(target_depth != 3) {
+        memset(untyped, 0, 0x1000);
+    }
+    untyped_entry->type = KO_NONE;
+#ifdef DBG_SYSCALL
+    klogf("map %p[%i] to %p[%i]\n", untyped_phys, target_depth, target_pml, ((uintptr_t)target_pml & 0xFFF) / 8);
+#endif
+
+    mtx_release(&untyped_entry->lock);
+    return 0;
+}
+
+static int
+s_handle_invoke_mapping_unmap(
+        objdir_t *root_dir, 
+        objdir_entry_t *target_entry, 
+        uint8_t *payload, 
+        size_t payload_at
+        )
+{
+    pmle_t *pml4 = (pmle_t*)vmem_phys_tovirt(target_entry->data);
+    pmle_t *target_pml;
+    uint8_t target_depth;
+    SYSCALL_PAYLOAD_TAKEPML(payload, payload_at, pml4, target_depth, target_pml);
+    if(target_pml == NULL || !target_pml->p) return KE_DNE;
+   
+    if(target_depth != 3) {
+        for(pmli_t i = 0; i < 512; i++) {
+            if(target_pml[i].p) return KE_FULL;
+        }
+    }
+
+    target_pml->p = false;
+
+    objdir_entry_t *dest_entry;
+    size_t dest_pathw;
+    SYSCALL_PAYLOAD_TAKEOBJ(payload, payload_at, dest_pathw, dest_entry);
+
+    if(dest_entry->type != KO_NONE) return KE_FULL;
+    uintptr_t pmle_addr = target_pml->paddr << 12;
+    size_t *untyped = vmem_phys_tovirt(pmle_addr);
+    __asm__ volatile("invlpg (%0)":: "r"(untyped): "memory");
+
+    *untyped = 0x1000;
+    dest_entry->type = KO_MEMORY_UNTYPED;
+    dest_entry->data = pmle_addr;
+
+#ifdef DBG_SYSCALL
+    klogf("unmap %p[%i] to untyped %p\n", target_pml, 3 - target_depth, pmle_addr);
+#endif
+    return 0;
+}
+
+static int (*s_invoke_handles[])(objdir_t*, objdir_entry_t*, uint8_t*, size_t) = {
+    [INVOKE_MAPPING_EXISTS] = s_handle_invoke_mapping_exists,
+    [INVOKE_MAPPING_MAP] = s_handle_invoke_mapping_map,
+    [INVOKE_MAPPING_UNMAP] = s_handle_invoke_mapping_unmap
+};
+
+static size_t s_invoke_handles_count = sizeof(s_invoke_handles) / sizeof(void*);
+
+int
+syscall_handle_invoke_mapping(
+        objdir_t *root_dir, 
+        objdir_entry_t *target, 
+        uint8_t *payload, 
+        size_t payload_at
+        )
+{
+    uint8_t funcid;
+    SYSCALL_PAYLOAD_TAKEL(payload, payload_at, funcid, uint8_t);
+
+    if(funcid >= s_invoke_handles_count) return KE_BADFUNC;
+    int r = s_invoke_handles[funcid](root_dir, target, payload, payload_at);
+#ifdef DBG_SYSCALL
+    klogf("Call returns %i\n", r);
+#endif
+    return r;
+}