add docs for syscalls. make syscall code kind-of cleaner

1 files changed, 74 insertions, 31 deletions

diff --git a/arch/x86_64/hal/paging.c b/arch/x86_64/hal/paging.c
index 9947e9c..2fbf26c 100644
--- a/arch/x86_64/hal/paging.c
+++ b/arch/x86_64/hal/paging.c
@@ -106,7 +106,7 @@ s_pagedir_get_pml1(page_t *pml4, uintptr_t vptr)
 }
 
 int pagedir_map_frame(page_t *pml4, 
-        uintptr_t pptr, uintptr_t vptr, 
+        uintptr_t pptr, uintptr_t vptr,
         uintmax_t flg)
 {
     page_t *pml1 = s_pagedir_get_pml1(pml4, vptr);
@@ -121,41 +121,35 @@ int pagedir_map_frame(page_t *pml4,
     return 0;
 }
 
-int pagedir_map_untyped_frame(
-        jove_owned_obj_t *tgt, jove_owned_obj_t *untyped_obj, 
-        uintptr_t vptr, struct syscall_pagedir_flags flg)
+int pagedir_map_shmem(page_t *pml4,
+        uintptr_t pptr, uintptr_t vptr,
+        struct syscall_pagedir_flags flg)
 {
-    page_t *pml4 = obj_deref(tgt);
-    uintptr_t frame = obj_getvalue(untyped_obj);
-
-    return pagedir_map_frame(pml4, frame, vptr, 
-            (flg.writeable ? PAGE_WRITEABLE : 0) |
-            PAGE_USER |
-            (flg.executable ? PAGE_XD : 0));
+    uintmax_t real_flg = PAGE_USER | PAGE_SHMEM;
+    if(flg.writeable) {
+        real_flg |= PAGE_WRITEABLE;
+    }
+    if(!flg.executable) {
+        real_flg |= PAGE_XD;
+    }
+    return pagedir_map_frame(pml4, pptr, vptr, real_flg);
 }
 
-int pagedir_unmap_untyped_frame(
-        jove_owned_obj_t *tgt, jove_owned_obj_t *dst, uintptr_t vptr)
+int pagedir_map_untyped_frame(
+        jove_owned_obj_t *tgt, jove_perm_obj_t *untyped, 
+        uintptr_t vptr, struct syscall_pagedir_flags flg)
 {
     page_t *pml4 = obj_deref(tgt);
 
-    size_t pml4i = PML4I(vptr);
-    if(!pml4[pml4i].p) return ENOMAP;
-
-    page_t *pml1 = s_pagedir_get_pml1(pml4, vptr);
-    size_t pml1i = PML1I(vptr);
-    if(!pml1[pml1i].p) return ENOMAP;
-
-    uintptr_t untyped_pptr = (pml1[pml1i].paddr << 12);
-    
-    obj_settype(dst, JOVE_OBJ_UNTYPED);
-    obj_setvalue(dst, untyped_pptr);
-
-    jove_untyped_t *untyped_data = obj_deref(dst);
-    untyped_data->limit = 0x1000;
-    __asm__ volatile("invlpg (%0)":: "r"(vptr): "memory");
+    if(flg.writeable && (untyped->permissions & JOVE_PERM_WRITE) == 0) {
+        kprintf("%s: Untyped object flagged for writeable mapping missing write permissions!\n", __func__);
+        return -EPERM;
+    }
 
-    return 0;
+    uintptr_t frame = obj_getvalue(untyped->obj);
+    return pagedir_map_frame(pml4, frame, vptr, PAGE_USER |
+            (flg.writeable ? PAGE_WRITEABLE : 0) |
+            (flg.executable ? 0 : PAGE_XD));
 }
 
 int pagedir_map_table(page_t *pml4,
@@ -199,14 +193,63 @@ map_table:
 }
 
 int pagedir_map_untyped_table(
-        jove_owned_obj_t *tgt, jove_owned_obj_t *untyped_obj, uintptr_t vptr)
+        jove_owned_obj_t *tgt, jove_perm_obj_t *untyped, uintptr_t vptr)
 {
     page_t *pml4 = obj_deref(tgt);
-    uintptr_t frame = obj_getvalue(untyped_obj);
+
+    if((untyped->permissions & JOVE_PERM_WRITE) == 0) {
+        kprintf("%s: Untyped object flagged for table mapping missing write permissions!\n", __func__);
+        return -EPERM;
+    }
+    uintptr_t frame = obj_getvalue(untyped->obj);
 
     return pagedir_map_table(pml4, frame, vptr);
 }
 
+int pagedir_map_shmem_frame(
+        jove_owned_obj_t *tgt, jove_perm_obj_t *shmem, uint8_t page_offset,
+        uintptr_t vptr, struct syscall_pagedir_flags flg)
+{
+    page_t *pml4 = obj_deref(tgt);
+
+    if(flg.writeable && (shmem->permissions & JOVE_PERM_WRITE) != 0) {
+        kprintf("%s: Shared memory object flagged for writeable mapping missing write permissions!\n", __func__);
+        return -EPERM;
+    }
+    
+    uintmax_t value = obj_getvalue(shmem->obj);
+    uintptr_t frame = value & ~0xFF;
+    frame += (uintmax_t)page_offset << 12;
+
+    return pagedir_map_frame(pml4, frame, vptr, PAGE_USER |
+            (flg.writeable ? PAGE_WRITEABLE : 0) |
+            (flg.executable ? 0 : PAGE_XD));
+}
+
+int pagedir_unmap_untyped_frame(
+        jove_owned_obj_t *tgt, jove_owned_obj_t *dst, uintptr_t vptr)
+{
+    page_t *pml4 = obj_deref(tgt);
+
+    size_t pml4i = PML4I(vptr);
+    if(!pml4[pml4i].p) return ENOMAP;
+
+    page_t *pml1 = s_pagedir_get_pml1(pml4, vptr);
+    size_t pml1i = PML1I(vptr);
+    if(!pml1[pml1i].p) return ENOMAP;
+
+    uintptr_t untyped_pptr = (pml1[pml1i].paddr << 12);
+    
+    obj_settype(dst, JOVE_OBJ_UNTYPED);
+    obj_setvalue(dst, untyped_pptr);
+
+    jove_untyped_t *untyped_data = obj_deref(dst);
+    untyped_data->limit = 0x1000;
+    __asm__ volatile("invlpg (%0)":: "r"(vptr): "memory");
+
+    return 0;
+}
+
 int pagedir_unmap_untyped_table(
         jove_owned_obj_t *tgt, jove_owned_obj_t *dst, uintptr_t vptr)
 {