1 files changed, 109 insertions, 0 deletions
diff --git a/arch/x86/machine/tcb.c b/arch/x86/machine/tcb.c
new file mode 100644
index 00000000..ee1cb4fe
--- /dev/null
+++ b/arch/x86/machine/tcb.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2012 Richard Braun.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <kern/error.h>
+#include <kern/init.h>
+#include <kern/kmem.h>
+#include <kern/param.h>
+#include <kern/stddef.h>
+#include <kern/string.h>
+#include <kern/thread.h>
+#include <machine/cpu.h>
+#include <machine/tcb.h>
+#include <machine/trap.h>
+
+static struct kmem_cache tcb_cache;
+
+void __init
+tcb_setup(void)
+{
+    kmem_cache_init(&tcb_cache, "tcb", sizeof(struct tcb),
+                    0, NULL, NULL, NULL, 0);
+}
+
+#ifdef __LP64__
+
+static void
+tcb_init_stack(struct tcb *tcb, void *stack, const struct thread *thread)
+{
+    struct trap_frame *frame;
+
+    frame = (struct trap_frame *)(stack + STACK_SIZE) - 1;
+    memset(frame, 0, sizeof(*frame));
+    frame->rdi = (unsigned long)thread;
+    frame->rip = (unsigned long)thread_main;
+    frame->cs = CPU_GDT_SEL_CODE;
+    frame->rflags = CPU_EFL_IF | CPU_EFL_ONE;
+    frame->rsp = (unsigned long)(stack + STACK_SIZE);
+    frame->ss = CPU_GDT_SEL_DATA;
+    tcb->frame = frame;
+}
+
+#else /* __LP64__ */
+
+static void
+tcb_init_stack(struct tcb *tcb, void *stack, const struct thread *thread)
+{
+    struct trap_frame *frame;
+    const struct thread **arg;
+    const void **ret_addr;
+    void *ptr;
+    size_t size;
+
+    /* Fake a function call (return address and argument) */
+    ptr = stack + STACK_SIZE - (2 * sizeof(long));
+    ret_addr = ptr;
+    *ret_addr = 0;
+    arg = ptr + sizeof(long);
+    *arg = thread;
+
+    /* Exclude user space stack registers */
+    size = sizeof(*frame) - (2 * sizeof(long));
+    frame = ptr - size;
+    memset(frame, 0, size);
+    frame->ds = CPU_GDT_SEL_DATA;
+    frame->es = CPU_GDT_SEL_DATA;
+    frame->fs = CPU_GDT_SEL_CPU;
+    frame->gs = CPU_GDT_SEL_NULL;
+    frame->eip = (unsigned long)thread_main;
+    frame->cs = CPU_GDT_SEL_CODE;
+    frame->eflags = CPU_EFL_IF | CPU_EFL_ONE;
+    tcb->frame = frame;
+}
+
+#endif /* __LP64__ */
+
+int
+tcb_create(struct tcb **tcbp, void *stack, const struct thread *thread)
+{
+    struct tcb *tcb;
+
+    tcb = kmem_cache_alloc(&tcb_cache);
+
+    if (tcb == NULL)
+        return ERROR_NOMEM;
+
+    tcb_init_stack(tcb, stack, thread);
+    *tcbp = tcb;
+    return 0;
+}
+
+void
+tcb_load(struct tcb *tcb)
+{
+    trap_load(tcb->frame);
+}