Move platform-specific code for process loading/init for AMD64 to amd64/

kernel/amd64/proc.c

@@ -0,0 +1,55 @@
+#include <libk/std.h>
+#include <libk/string.h>
+#include <sync/spin_lock.h>
+#include <mm/pmm.h>
+#include <mm/liballoc.h>
+#include <proc/proc.h>
+#include <aux/elf.h>
+
+struct proc* proc_from_elf (uint8_t* elf_contents) {
+  struct proc* proc = malloc (sizeof (*proc));
+  if (proc == NULL)
+    return NULL;
+
+  memset (proc, 0, sizeof (*proc));
+
+  proc->pd.lock = SPIN_LOCK_INIT;
+  proc->pd.cr3_paddr = mm_alloc_user_pd_phys ();
+  if (proc->pd.cr3_paddr == 0) {
+    free (proc);
+    return NULL;
+  }
+
+  proc->pdata.syscall_stack = pmm_alloc (KSTACK_SIZE / PAGE_SIZE);
+  if (proc->pdata.syscall_stack == PMM_ALLOC_ERR) {
+    free (proc);
+    return NULL;
+  }
+
+  proc->pdata.user_stack = pmm_alloc (USTACK_SIZE / PAGE_SIZE);
+  if (proc->pdata.user_stack == PMM_ALLOC_ERR) {
+    free (proc);
+    pmm_free (proc->pdata.syscall_stack, USTACK_SIZE / PAGE_SIZE);
+    return NULL;
+  }
+
+  uintptr_t user_stack = proc->pdata.user_stack;
+
+  proc->pdata.syscall_stack += KSTACK_SIZE;
+  proc->pdata.user_stack += USTACK_SIZE;
+
+  proc_map (proc, user_stack, PROC_USTACK_TOP - USTACK_SIZE, USTACK_SIZE / PAGE_SIZE,
+            MM_PG_USER | MM_PG_PRESENT | MM_PG_RW);
+
+  struct elf_aux aux = proc_load_segments (proc, elf_contents);
+
+  proc->pdata.regs.ss = 0x20 | 0x03;
+  proc->pdata.regs.rsp = (uint64_t)PROC_USTACK_TOP;
+  proc->pdata.regs.rflags = 0x202;
+  proc->pdata.regs.cs = 0x18 | 0x03;
+  proc->pdata.regs.rip = aux.entry;
+  proc->lock = SPIN_LOCK_INIT;
+  atomic_store (&proc->state, PROC_READY);
+
+  return proc;
+}