2 * Copyright (c) 2003,2004,2008 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by David Xu <davidxu@t2t2.com> and Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/sysproto.h>
39 #include <sys/kernel.h>
41 #include <sys/sysent.h>
42 #include <sys/sysctl.h>
45 #include <sys/globaldata.h>
47 #include <sys/thread2.h>
49 #include <machine/cpu.h>
50 #include <machine/clock.h>
51 #include <machine/specialreg.h>
52 #include <machine/segments.h>
53 #include <machine/md_var.h>
54 #include <machine/pcb_ext.h> /* pcb.h included via sys/user.h */
55 #include <machine/globaldata.h> /* CPU_prvspace */
56 #include <machine/smp.h>
57 #include <machine/pcb.h>
60 * set a TLS descriptor. For x86_64 descriptor 0 identifies %fs and
61 * descriptor 1 identifies %gs, and 0 is returned in sysmsg_result.
63 * Returns the value userland needs to load into %gs representing the
64 * TLS descriptor or -1 on error.
66 * (int which, struct tls_info *info, size_t infosize)
69 sys_set_tls_area(struct set_tls_area_args *uap)
78 * which 0 == %fs, which 1 == %gs
83 if (uap->infosize < 0)
87 * Maintain forwards compatibility with future extensions.
89 if (uap->infosize != sizeof(info)) {
90 bzero(&info, sizeof(info));
91 error = copyin(uap->info, &info,
92 min(sizeof(info), uap->infosize));
94 error = copyin(uap->info, &info, sizeof(info));
102 * For x86_64 we can only adjust FSBASE and GSBASE
104 curthread->td_tls.info[i] = info;
106 uap->sysmsg_result = 0; /* segment descriptor $0 */
111 * Return the specified TLS descriptor to userland.
113 * Returns the value userland needs to load into %gs representing the
114 * TLS descriptor or -1 on error.
116 * (int which, struct tls_info *info, size_t infosize)
119 sys_get_tls_area(struct get_tls_area_args *uap)
121 struct tls_info info;
131 if (uap->infosize < 0)
134 info = curthread->td_tls.info[i];
136 error = copyout(&info, uap->info, min(sizeof(info), uap->infosize));
141 * This function is a NOP because the TLS segments are proactively copied
142 * by vmspace_ctl() when we switch to the (emulated) user process.