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-rw-r--r--i386/i386/ldt.c117
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diff --git a/i386/i386/ldt.c b/i386/i386/ldt.c
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+/*
+ * Mach Operating System
+ * Copyright (c) 1991,1990 Carnegie Mellon University
+ * All Rights Reserved.
+ *
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ *
+ * Carnegie Mellon requests users of this software to return to
+ *
+ * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
+ * School of Computer Science
+ * Carnegie Mellon University
+ * Pittsburgh PA 15213-3890
+ *
+ * any improvements or extensions that they make and grant Carnegie Mellon
+ * the rights to redistribute these changes.
+ */
+/*
+ * "Local" descriptor table. At the moment, all tasks use the
+ * same LDT.
+ */
+#include <mach/machine/eflags.h>
+#include <mach/machine/vm_types.h>
+#include <mach/xen.h>
+
+#include <intel/pmap.h>
+#include <kern/debug.h>
+
+#include "vm_param.h"
+#include "seg.h"
+#include "gdt.h"
+#include "ldt.h"
+#include "locore.h"
+#include "mp_desc.h"
+#include "msr.h"
+
+#ifdef MACH_PV_DESCRIPTORS
+/* It is actually defined in xen_boothdr.S */
+extern
+#endif /* MACH_PV_DESCRIPTORS */
+struct real_descriptor ldt[LDTSZ];
+
+#if defined(__x86_64__) && ! defined(USER32)
+#define USER_SEGMENT_SIZEBITS SZ_64
+#else
+#define USER_SEGMENT_SIZEBITS SZ_32
+#endif
+
+void
+ldt_fill(struct real_descriptor *myldt, struct real_descriptor *mygdt)
+{
+#ifdef MACH_PV_DESCRIPTORS
+#ifdef MACH_PV_PAGETABLES
+ pmap_set_page_readwrite(myldt);
+#endif /* MACH_PV_PAGETABLES */
+#else /* MACH_PV_DESCRIPTORS */
+ /* Initialize the master LDT descriptor in the GDT. */
+ _fill_gdt_sys_descriptor(mygdt, KERNEL_LDT,
+ kvtolin(myldt), (LDTSZ * sizeof(struct real_descriptor))-1,
+ ACC_PL_K|ACC_LDT, 0);
+#endif /* MACH_PV_DESCRIPTORS */
+
+ /* Initialize the syscall entry point */
+#if defined(__x86_64__) && ! defined(USER32)
+ if (!CPU_HAS_FEATURE(CPU_FEATURE_SEP))
+ panic("syscall support is missing on 64 bit");
+ /* Enable 64-bit syscalls */
+ wrmsr(MSR_REG_EFER, rdmsr(MSR_REG_EFER) | MSR_EFER_SCE);
+ wrmsr(MSR_REG_LSTAR, (vm_offset_t)syscall64);
+ wrmsr(MSR_REG_STAR, ((((long)USER_CS - 16) << 16) | (long)KERNEL_CS) << 32);
+ wrmsr(MSR_REG_FMASK, EFL_IF | EFL_IOPL_USER);
+#else /* defined(__x86_64__) && ! defined(USER32) */
+ fill_ldt_gate(myldt, USER_SCALL,
+ (vm_offset_t)&syscall, KERNEL_CS,
+ ACC_PL_U|ACC_CALL_GATE, 0);
+#endif /* defined(__x86_64__) && ! defined(USER32) */
+
+ /* Initialize the 32bit LDT descriptors. */
+ fill_ldt_descriptor(myldt, USER_CS,
+ VM_MIN_USER_ADDRESS,
+ VM_MAX_USER_ADDRESS-VM_MIN_USER_ADDRESS-4096,
+ /* XXX LINEAR_... */
+ ACC_PL_U|ACC_CODE_R, USER_SEGMENT_SIZEBITS);
+ fill_ldt_descriptor(myldt, USER_DS,
+ VM_MIN_USER_ADDRESS,
+ VM_MAX_USER_ADDRESS-VM_MIN_USER_ADDRESS-4096,
+ ACC_PL_U|ACC_DATA_W, USER_SEGMENT_SIZEBITS);
+
+ /* Activate the LDT. */
+#ifdef MACH_PV_DESCRIPTORS
+ hyp_set_ldt(myldt, LDTSZ);
+#else /* MACH_PV_DESCRIPTORS */
+ lldt(KERNEL_LDT);
+#endif /* MACH_PV_DESCRIPTORS */
+}
+
+void
+ldt_init(void)
+{
+ ldt_fill(ldt, gdt);
+}
+
+#if NCPUS > 1
+void
+ap_ldt_init(int cpu)
+{
+ ldt_fill(mp_desc_table[cpu]->ldt, mp_gdt[cpu]);
+}
+#endif