Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/x86-64/kernel/process.c |
| 3 | * |
| 4 | * Copyright (C) 1995 Linus Torvalds |
| 5 | * |
| 6 | * Pentium III FXSR, SSE support |
| 7 | * Gareth Hughes <gareth@valinux.com>, May 2000 |
| 8 | * |
| 9 | * X86-64 port |
| 10 | * Andi Kleen. |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 11 | * |
| 12 | * CPU hotplug support - ashok.raj@intel.com |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | */ |
| 14 | |
| 15 | /* |
| 16 | * This file handles the architecture-dependent parts of process handling.. |
| 17 | */ |
| 18 | |
| 19 | #include <stdarg.h> |
| 20 | |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 21 | #include <linux/cpu.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <linux/errno.h> |
| 23 | #include <linux/sched.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/mm.h> |
| 26 | #include <linux/elfcore.h> |
| 27 | #include <linux/smp.h> |
| 28 | #include <linux/slab.h> |
| 29 | #include <linux/user.h> |
| 30 | #include <linux/module.h> |
| 31 | #include <linux/a.out.h> |
| 32 | #include <linux/interrupt.h> |
| 33 | #include <linux/delay.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | #include <linux/ptrace.h> |
| 35 | #include <linux/utsname.h> |
| 36 | #include <linux/random.h> |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 37 | #include <linux/notifier.h> |
bibo mao | c6fd91f | 2006-03-26 01:38:20 -0800 | [diff] [blame] | 38 | #include <linux/kprobes.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | |
| 40 | #include <asm/uaccess.h> |
| 41 | #include <asm/pgtable.h> |
| 42 | #include <asm/system.h> |
| 43 | #include <asm/io.h> |
| 44 | #include <asm/processor.h> |
| 45 | #include <asm/i387.h> |
| 46 | #include <asm/mmu_context.h> |
| 47 | #include <asm/pda.h> |
| 48 | #include <asm/prctl.h> |
| 49 | #include <asm/kdebug.h> |
| 50 | #include <asm/desc.h> |
| 51 | #include <asm/proto.h> |
| 52 | #include <asm/ia32.h> |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 53 | #include <asm/idle.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
| 55 | asmlinkage extern void ret_from_fork(void); |
| 56 | |
| 57 | unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED; |
| 58 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | unsigned long boot_option_idle_override = 0; |
| 60 | EXPORT_SYMBOL(boot_option_idle_override); |
| 61 | |
| 62 | /* |
| 63 | * Powermanagement idle function, if any.. |
| 64 | */ |
| 65 | void (*pm_idle)(void); |
Andi Kleen | 2ee60e17 | 2006-06-26 13:59:44 +0200 | [diff] [blame] | 66 | EXPORT_SYMBOL(pm_idle); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | static DEFINE_PER_CPU(unsigned int, cpu_idle_state); |
| 68 | |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 69 | static ATOMIC_NOTIFIER_HEAD(idle_notifier); |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 70 | |
| 71 | void idle_notifier_register(struct notifier_block *n) |
| 72 | { |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 73 | atomic_notifier_chain_register(&idle_notifier, n); |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 74 | } |
| 75 | EXPORT_SYMBOL_GPL(idle_notifier_register); |
| 76 | |
| 77 | void idle_notifier_unregister(struct notifier_block *n) |
| 78 | { |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 79 | atomic_notifier_chain_unregister(&idle_notifier, n); |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 80 | } |
| 81 | EXPORT_SYMBOL(idle_notifier_unregister); |
| 82 | |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 83 | void enter_idle(void) |
| 84 | { |
Andi Kleen | a15da49 | 2006-09-26 10:52:40 +0200 | [diff] [blame] | 85 | write_pda(isidle, 1); |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 86 | atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL); |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 87 | } |
| 88 | |
| 89 | static void __exit_idle(void) |
| 90 | { |
Andi Kleen | 9446868 | 2006-11-14 16:57:46 +0100 | [diff] [blame] | 91 | if (test_and_clear_bit_pda(0, isidle) == 0) |
Andi Kleen | a15da49 | 2006-09-26 10:52:40 +0200 | [diff] [blame] | 92 | return; |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 93 | atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL); |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 94 | } |
| 95 | |
| 96 | /* Called from interrupts to signify idle end */ |
| 97 | void exit_idle(void) |
| 98 | { |
Andi Kleen | a15da49 | 2006-09-26 10:52:40 +0200 | [diff] [blame] | 99 | /* idle loop has pid 0 */ |
| 100 | if (current->pid) |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 101 | return; |
| 102 | __exit_idle(); |
| 103 | } |
| 104 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | /* |
| 106 | * We use this if we don't have any better |
| 107 | * idle routine.. |
| 108 | */ |
Adrian Bunk | cdb0452 | 2006-03-24 03:15:57 -0800 | [diff] [blame] | 109 | static void default_idle(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | { |
Andi Kleen | 495ab9c | 2006-06-26 13:59:11 +0200 | [diff] [blame] | 111 | current_thread_info()->status &= ~TS_POLLING; |
Ingo Molnar | 0888f06 | 2006-12-22 01:11:56 -0800 | [diff] [blame] | 112 | /* |
| 113 | * TS_POLLING-cleared state must be visible before we |
| 114 | * test NEED_RESCHED: |
| 115 | */ |
| 116 | smp_mb(); |
Andi Kleen | 72690a2 | 2006-12-07 02:14:03 +0100 | [diff] [blame] | 117 | local_irq_disable(); |
| 118 | if (!need_resched()) { |
| 119 | /* Enables interrupts one instruction before HLT. |
| 120 | x86 special cases this so there is no race. */ |
| 121 | safe_halt(); |
| 122 | } else |
| 123 | local_irq_enable(); |
Andi Kleen | 495ab9c | 2006-06-26 13:59:11 +0200 | [diff] [blame] | 124 | current_thread_info()->status |= TS_POLLING; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | } |
| 126 | |
| 127 | /* |
| 128 | * On SMP it's slightly faster (but much more power-consuming!) |
| 129 | * to poll the ->need_resched flag instead of waiting for the |
| 130 | * cross-CPU IPI to arrive. Use this option with caution. |
| 131 | */ |
| 132 | static void poll_idle (void) |
| 133 | { |
Venkatesh Pallipadi | d331e73 | 2006-12-07 02:14:13 +0100 | [diff] [blame] | 134 | local_irq_enable(); |
Andi Kleen | 72690a2 | 2006-12-07 02:14:03 +0100 | [diff] [blame] | 135 | cpu_relax(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | } |
| 137 | |
| 138 | void cpu_idle_wait(void) |
| 139 | { |
| 140 | unsigned int cpu, this_cpu = get_cpu(); |
Ingo Molnar | dc1829a | 2006-11-17 14:26:18 +0100 | [diff] [blame] | 141 | cpumask_t map, tmp = current->cpus_allowed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | |
| 143 | set_cpus_allowed(current, cpumask_of_cpu(this_cpu)); |
| 144 | put_cpu(); |
| 145 | |
| 146 | cpus_clear(map); |
| 147 | for_each_online_cpu(cpu) { |
| 148 | per_cpu(cpu_idle_state, cpu) = 1; |
| 149 | cpu_set(cpu, map); |
| 150 | } |
| 151 | |
| 152 | __get_cpu_var(cpu_idle_state) = 0; |
| 153 | |
| 154 | wmb(); |
| 155 | do { |
| 156 | ssleep(1); |
| 157 | for_each_online_cpu(cpu) { |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 158 | if (cpu_isset(cpu, map) && |
| 159 | !per_cpu(cpu_idle_state, cpu)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | cpu_clear(cpu, map); |
| 161 | } |
| 162 | cpus_and(map, map, cpu_online_map); |
| 163 | } while (!cpus_empty(map)); |
Ingo Molnar | dc1829a | 2006-11-17 14:26:18 +0100 | [diff] [blame] | 164 | |
| 165 | set_cpus_allowed(current, tmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | } |
| 167 | EXPORT_SYMBOL_GPL(cpu_idle_wait); |
| 168 | |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 169 | #ifdef CONFIG_HOTPLUG_CPU |
| 170 | DECLARE_PER_CPU(int, cpu_state); |
| 171 | |
| 172 | #include <asm/nmi.h> |
Shaohua Li | 1fa744e | 2006-01-06 00:12:20 -0800 | [diff] [blame] | 173 | /* We halt the CPU with physical CPU hotplug */ |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 174 | static inline void play_dead(void) |
| 175 | { |
| 176 | idle_task_exit(); |
| 177 | wbinvd(); |
| 178 | mb(); |
| 179 | /* Ack it */ |
| 180 | __get_cpu_var(cpu_state) = CPU_DEAD; |
| 181 | |
Shaohua Li | 1fa744e | 2006-01-06 00:12:20 -0800 | [diff] [blame] | 182 | local_irq_disable(); |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 183 | while (1) |
Shaohua Li | 1fa744e | 2006-01-06 00:12:20 -0800 | [diff] [blame] | 184 | halt(); |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 185 | } |
| 186 | #else |
| 187 | static inline void play_dead(void) |
| 188 | { |
| 189 | BUG(); |
| 190 | } |
| 191 | #endif /* CONFIG_HOTPLUG_CPU */ |
| 192 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | /* |
| 194 | * The idle thread. There's no useful work to be |
| 195 | * done, so just try to conserve power and have a |
| 196 | * low exit latency (ie sit in a loop waiting for |
| 197 | * somebody to say that they'd like to reschedule) |
| 198 | */ |
| 199 | void cpu_idle (void) |
| 200 | { |
Andi Kleen | 495ab9c | 2006-06-26 13:59:11 +0200 | [diff] [blame] | 201 | current_thread_info()->status |= TS_POLLING; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | /* endless idle loop with no priority at all */ |
| 203 | while (1) { |
| 204 | while (!need_resched()) { |
| 205 | void (*idle)(void); |
| 206 | |
| 207 | if (__get_cpu_var(cpu_idle_state)) |
| 208 | __get_cpu_var(cpu_idle_state) = 0; |
| 209 | |
| 210 | rmb(); |
| 211 | idle = pm_idle; |
| 212 | if (!idle) |
| 213 | idle = default_idle; |
Ashok Raj | 76e4f66 | 2005-06-25 14:55:00 -0700 | [diff] [blame] | 214 | if (cpu_is_offline(smp_processor_id())) |
| 215 | play_dead(); |
Venkatesh Pallipadi | d331e73 | 2006-12-07 02:14:13 +0100 | [diff] [blame] | 216 | /* |
| 217 | * Idle routines should keep interrupts disabled |
| 218 | * from here on, until they go to idle. |
| 219 | * Otherwise, idle callbacks can misfire. |
| 220 | */ |
| 221 | local_irq_disable(); |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 222 | enter_idle(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | idle(); |
Andi Kleen | a15da49 | 2006-09-26 10:52:40 +0200 | [diff] [blame] | 224 | /* In many cases the interrupt that ended idle |
| 225 | has already called exit_idle. But some idle |
| 226 | loops can be woken up without interrupt. */ |
Andi Kleen | 95833c8 | 2006-01-11 22:44:36 +0100 | [diff] [blame] | 227 | __exit_idle(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | } |
| 229 | |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 230 | preempt_enable_no_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | schedule(); |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 232 | preempt_disable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | } |
| 234 | } |
| 235 | |
| 236 | /* |
| 237 | * This uses new MONITOR/MWAIT instructions on P4 processors with PNI, |
| 238 | * which can obviate IPI to trigger checking of need_resched. |
| 239 | * We execute MONITOR against need_resched and enter optimized wait state |
| 240 | * through MWAIT. Whenever someone changes need_resched, we would be woken |
| 241 | * up from MWAIT (without an IPI). |
Venkatesh Pallipadi | 991528d | 2006-09-25 16:28:13 -0700 | [diff] [blame] | 242 | * |
| 243 | * New with Core Duo processors, MWAIT can take some hints based on CPU |
| 244 | * capability. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | */ |
Venkatesh Pallipadi | 991528d | 2006-09-25 16:28:13 -0700 | [diff] [blame] | 246 | void mwait_idle_with_hints(unsigned long eax, unsigned long ecx) |
| 247 | { |
| 248 | if (!need_resched()) { |
| 249 | __monitor((void *)¤t_thread_info()->flags, 0, 0); |
| 250 | smp_mb(); |
| 251 | if (!need_resched()) |
| 252 | __mwait(eax, ecx); |
| 253 | } |
| 254 | } |
| 255 | |
| 256 | /* Default MONITOR/MWAIT with no hints, used for default C1 state */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | static void mwait_idle(void) |
| 258 | { |
Venkatesh Pallipadi | d331e73 | 2006-12-07 02:14:13 +0100 | [diff] [blame] | 259 | if (!need_resched()) { |
| 260 | __monitor((void *)¤t_thread_info()->flags, 0, 0); |
| 261 | smp_mb(); |
| 262 | if (!need_resched()) |
| 263 | __sti_mwait(0, 0); |
| 264 | else |
| 265 | local_irq_enable(); |
| 266 | } else { |
| 267 | local_irq_enable(); |
| 268 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | } |
| 270 | |
Ashok Raj | e6982c6 | 2005-06-25 14:54:58 -0700 | [diff] [blame] | 271 | void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | { |
| 273 | static int printed; |
| 274 | if (cpu_has(c, X86_FEATURE_MWAIT)) { |
| 275 | /* |
| 276 | * Skip, if setup has overridden idle. |
| 277 | * One CPU supports mwait => All CPUs supports mwait |
| 278 | */ |
| 279 | if (!pm_idle) { |
| 280 | if (!printed) { |
| 281 | printk("using mwait in idle threads.\n"); |
| 282 | printed = 1; |
| 283 | } |
| 284 | pm_idle = mwait_idle; |
| 285 | } |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | static int __init idle_setup (char *str) |
| 290 | { |
| 291 | if (!strncmp(str, "poll", 4)) { |
| 292 | printk("using polling idle threads.\n"); |
| 293 | pm_idle = poll_idle; |
| 294 | } |
| 295 | |
| 296 | boot_option_idle_override = 1; |
| 297 | return 1; |
| 298 | } |
| 299 | |
| 300 | __setup("idle=", idle_setup); |
| 301 | |
| 302 | /* Prints also some state that isn't saved in the pt_regs */ |
| 303 | void __show_regs(struct pt_regs * regs) |
| 304 | { |
| 305 | unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs; |
| 306 | unsigned int fsindex,gsindex; |
| 307 | unsigned int ds,cs,es; |
| 308 | |
| 309 | printk("\n"); |
| 310 | print_modules(); |
Andi Kleen | 9acf23c | 2005-09-12 18:49:24 +0200 | [diff] [blame] | 311 | printk("Pid: %d, comm: %.20s %s %s %.*s\n", |
| 312 | current->pid, current->comm, print_tainted(), |
Serge E. Hallyn | 96b644b | 2006-10-02 02:18:13 -0700 | [diff] [blame] | 313 | init_utsname()->release, |
| 314 | (int)strcspn(init_utsname()->version, " "), |
| 315 | init_utsname()->version); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip); |
| 317 | printk_address(regs->rip); |
Ingo Molnar | 3ac9493 | 2006-07-03 00:24:36 -0700 | [diff] [blame] | 318 | printk("RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp, |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 319 | regs->eflags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | printk("RAX: %016lx RBX: %016lx RCX: %016lx\n", |
| 321 | regs->rax, regs->rbx, regs->rcx); |
| 322 | printk("RDX: %016lx RSI: %016lx RDI: %016lx\n", |
| 323 | regs->rdx, regs->rsi, regs->rdi); |
| 324 | printk("RBP: %016lx R08: %016lx R09: %016lx\n", |
| 325 | regs->rbp, regs->r8, regs->r9); |
| 326 | printk("R10: %016lx R11: %016lx R12: %016lx\n", |
| 327 | regs->r10, regs->r11, regs->r12); |
| 328 | printk("R13: %016lx R14: %016lx R15: %016lx\n", |
| 329 | regs->r13, regs->r14, regs->r15); |
| 330 | |
| 331 | asm("movl %%ds,%0" : "=r" (ds)); |
| 332 | asm("movl %%cs,%0" : "=r" (cs)); |
| 333 | asm("movl %%es,%0" : "=r" (es)); |
| 334 | asm("movl %%fs,%0" : "=r" (fsindex)); |
| 335 | asm("movl %%gs,%0" : "=r" (gsindex)); |
| 336 | |
| 337 | rdmsrl(MSR_FS_BASE, fs); |
| 338 | rdmsrl(MSR_GS_BASE, gs); |
| 339 | rdmsrl(MSR_KERNEL_GS_BASE, shadowgs); |
| 340 | |
| 341 | asm("movq %%cr0, %0": "=r" (cr0)); |
| 342 | asm("movq %%cr2, %0": "=r" (cr2)); |
| 343 | asm("movq %%cr3, %0": "=r" (cr3)); |
| 344 | asm("movq %%cr4, %0": "=r" (cr4)); |
| 345 | |
| 346 | printk("FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", |
| 347 | fs,fsindex,gs,gsindex,shadowgs); |
| 348 | printk("CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds, es, cr0); |
| 349 | printk("CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3, cr4); |
| 350 | } |
| 351 | |
| 352 | void show_regs(struct pt_regs *regs) |
| 353 | { |
Zwane Mwaikambo | c078d32 | 2005-09-06 15:16:16 -0700 | [diff] [blame] | 354 | printk("CPU %d:", smp_processor_id()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | __show_regs(regs); |
Jan Beulich | b538ed2 | 2006-06-26 13:57:32 +0200 | [diff] [blame] | 356 | show_trace(NULL, regs, (void *)(regs + 1)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | } |
| 358 | |
| 359 | /* |
| 360 | * Free current thread data structures etc.. |
| 361 | */ |
| 362 | void exit_thread(void) |
| 363 | { |
| 364 | struct task_struct *me = current; |
| 365 | struct thread_struct *t = &me->thread; |
Rusty Lynch | 73649da | 2005-06-23 00:09:23 -0700 | [diff] [blame] | 366 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | if (me->thread.io_bitmap_ptr) { |
| 368 | struct tss_struct *tss = &per_cpu(init_tss, get_cpu()); |
| 369 | |
| 370 | kfree(t->io_bitmap_ptr); |
| 371 | t->io_bitmap_ptr = NULL; |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 372 | clear_thread_flag(TIF_IO_BITMAP); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | /* |
| 374 | * Careful, clear this in the TSS too: |
| 375 | */ |
| 376 | memset(tss->io_bitmap, 0xff, t->io_bitmap_max); |
| 377 | t->io_bitmap_max = 0; |
| 378 | put_cpu(); |
| 379 | } |
| 380 | } |
| 381 | |
| 382 | void flush_thread(void) |
| 383 | { |
| 384 | struct task_struct *tsk = current; |
| 385 | struct thread_info *t = current_thread_info(); |
| 386 | |
Andi Kleen | 4d9bc79 | 2006-06-26 13:57:19 +0200 | [diff] [blame] | 387 | if (t->flags & _TIF_ABI_PENDING) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | t->flags ^= (_TIF_ABI_PENDING | _TIF_IA32); |
Andi Kleen | 4d9bc79 | 2006-06-26 13:57:19 +0200 | [diff] [blame] | 389 | if (t->flags & _TIF_IA32) |
| 390 | current_thread_info()->status |= TS_COMPAT; |
| 391 | } |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 392 | t->flags &= ~_TIF_DEBUG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | |
| 394 | tsk->thread.debugreg0 = 0; |
| 395 | tsk->thread.debugreg1 = 0; |
| 396 | tsk->thread.debugreg2 = 0; |
| 397 | tsk->thread.debugreg3 = 0; |
| 398 | tsk->thread.debugreg6 = 0; |
| 399 | tsk->thread.debugreg7 = 0; |
| 400 | memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); |
| 401 | /* |
| 402 | * Forget coprocessor state.. |
| 403 | */ |
| 404 | clear_fpu(tsk); |
| 405 | clear_used_math(); |
| 406 | } |
| 407 | |
| 408 | void release_thread(struct task_struct *dead_task) |
| 409 | { |
| 410 | if (dead_task->mm) { |
| 411 | if (dead_task->mm->context.size) { |
| 412 | printk("WARNING: dead process %8s still has LDT? <%p/%d>\n", |
| 413 | dead_task->comm, |
| 414 | dead_task->mm->context.ldt, |
| 415 | dead_task->mm->context.size); |
| 416 | BUG(); |
| 417 | } |
| 418 | } |
| 419 | } |
| 420 | |
| 421 | static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr) |
| 422 | { |
| 423 | struct user_desc ud = { |
| 424 | .base_addr = addr, |
| 425 | .limit = 0xfffff, |
| 426 | .seg_32bit = 1, |
| 427 | .limit_in_pages = 1, |
| 428 | .useable = 1, |
| 429 | }; |
| 430 | struct n_desc_struct *desc = (void *)t->thread.tls_array; |
| 431 | desc += tls; |
| 432 | desc->a = LDT_entry_a(&ud); |
| 433 | desc->b = LDT_entry_b(&ud); |
| 434 | } |
| 435 | |
| 436 | static inline u32 read_32bit_tls(struct task_struct *t, int tls) |
| 437 | { |
| 438 | struct desc_struct *desc = (void *)t->thread.tls_array; |
| 439 | desc += tls; |
| 440 | return desc->base0 | |
| 441 | (((u32)desc->base1) << 16) | |
| 442 | (((u32)desc->base2) << 24); |
| 443 | } |
| 444 | |
| 445 | /* |
| 446 | * This gets called before we allocate a new thread and copy |
| 447 | * the current task into it. |
| 448 | */ |
| 449 | void prepare_to_copy(struct task_struct *tsk) |
| 450 | { |
| 451 | unlazy_fpu(tsk); |
| 452 | } |
| 453 | |
| 454 | int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp, |
| 455 | unsigned long unused, |
| 456 | struct task_struct * p, struct pt_regs * regs) |
| 457 | { |
| 458 | int err; |
| 459 | struct pt_regs * childregs; |
| 460 | struct task_struct *me = current; |
| 461 | |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 462 | childregs = ((struct pt_regs *) |
Al Viro | 57eafdc | 2006-01-12 01:05:39 -0800 | [diff] [blame] | 463 | (THREAD_SIZE + task_stack_page(p))) - 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | *childregs = *regs; |
| 465 | |
| 466 | childregs->rax = 0; |
| 467 | childregs->rsp = rsp; |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 468 | if (rsp == ~0UL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | childregs->rsp = (unsigned long)childregs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | |
| 471 | p->thread.rsp = (unsigned long) childregs; |
| 472 | p->thread.rsp0 = (unsigned long) (childregs+1); |
| 473 | p->thread.userrsp = me->thread.userrsp; |
| 474 | |
Al Viro | e4f17c4 | 2006-01-12 01:05:38 -0800 | [diff] [blame] | 475 | set_tsk_thread_flag(p, TIF_FORK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | |
| 477 | p->thread.fs = me->thread.fs; |
| 478 | p->thread.gs = me->thread.gs; |
| 479 | |
H. J. Lu | fd51f66 | 2005-05-01 08:58:48 -0700 | [diff] [blame] | 480 | asm("mov %%gs,%0" : "=m" (p->thread.gsindex)); |
| 481 | asm("mov %%fs,%0" : "=m" (p->thread.fsindex)); |
| 482 | asm("mov %%es,%0" : "=m" (p->thread.es)); |
| 483 | asm("mov %%ds,%0" : "=m" (p->thread.ds)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 485 | if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL); |
| 487 | if (!p->thread.io_bitmap_ptr) { |
| 488 | p->thread.io_bitmap_max = 0; |
| 489 | return -ENOMEM; |
| 490 | } |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 491 | memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr, |
| 492 | IO_BITMAP_BYTES); |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 493 | set_tsk_thread_flag(p, TIF_IO_BITMAP); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | } |
| 495 | |
| 496 | /* |
| 497 | * Set a new TLS for the child thread? |
| 498 | */ |
| 499 | if (clone_flags & CLONE_SETTLS) { |
| 500 | #ifdef CONFIG_IA32_EMULATION |
| 501 | if (test_thread_flag(TIF_IA32)) |
| 502 | err = ia32_child_tls(p, childregs); |
| 503 | else |
| 504 | #endif |
| 505 | err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8); |
| 506 | if (err) |
| 507 | goto out; |
| 508 | } |
| 509 | err = 0; |
| 510 | out: |
| 511 | if (err && p->thread.io_bitmap_ptr) { |
| 512 | kfree(p->thread.io_bitmap_ptr); |
| 513 | p->thread.io_bitmap_max = 0; |
| 514 | } |
| 515 | return err; |
| 516 | } |
| 517 | |
| 518 | /* |
| 519 | * This special macro can be used to load a debugging register |
| 520 | */ |
Jan Beulich | 2b514e7 | 2006-03-25 16:29:22 +0100 | [diff] [blame] | 521 | #define loaddebug(thread,r) set_debugreg(thread->debugreg ## r, r) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 523 | static inline void __switch_to_xtra(struct task_struct *prev_p, |
| 524 | struct task_struct *next_p, |
| 525 | struct tss_struct *tss) |
| 526 | { |
| 527 | struct thread_struct *prev, *next; |
| 528 | |
| 529 | prev = &prev_p->thread, |
| 530 | next = &next_p->thread; |
| 531 | |
| 532 | if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { |
| 533 | loaddebug(next, 0); |
| 534 | loaddebug(next, 1); |
| 535 | loaddebug(next, 2); |
| 536 | loaddebug(next, 3); |
| 537 | /* no 4 and 5 */ |
| 538 | loaddebug(next, 6); |
| 539 | loaddebug(next, 7); |
| 540 | } |
| 541 | |
| 542 | if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) { |
| 543 | /* |
| 544 | * Copy the relevant range of the IO bitmap. |
| 545 | * Normally this is 128 bytes or less: |
| 546 | */ |
| 547 | memcpy(tss->io_bitmap, next->io_bitmap_ptr, |
| 548 | max(prev->io_bitmap_max, next->io_bitmap_max)); |
| 549 | } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) { |
| 550 | /* |
| 551 | * Clear any possible leftover bits: |
| 552 | */ |
| 553 | memset(tss->io_bitmap, 0xff, prev->io_bitmap_max); |
| 554 | } |
| 555 | } |
| 556 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | /* |
| 558 | * switch_to(x,y) should switch tasks from x to y. |
| 559 | * |
| 560 | * This could still be optimized: |
| 561 | * - fold all the options into a flag word and test it with a single test. |
| 562 | * - could test fs/gs bitsliced |
Andi Kleen | 099f318 | 2006-02-03 21:51:38 +0100 | [diff] [blame] | 563 | * |
| 564 | * Kprobes not supported here. Set the probe on schedule instead. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | */ |
Andi Kleen | 099f318 | 2006-02-03 21:51:38 +0100 | [diff] [blame] | 566 | __kprobes struct task_struct * |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 567 | __switch_to(struct task_struct *prev_p, struct task_struct *next_p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | { |
| 569 | struct thread_struct *prev = &prev_p->thread, |
| 570 | *next = &next_p->thread; |
| 571 | int cpu = smp_processor_id(); |
| 572 | struct tss_struct *tss = &per_cpu(init_tss, cpu); |
| 573 | |
Arjan van de Ven | e07e23e | 2006-09-26 10:52:36 +0200 | [diff] [blame] | 574 | /* we're going to use this soon, after a few expensive things */ |
| 575 | if (next_p->fpu_counter>5) |
| 576 | prefetch(&next->i387.fxsave); |
| 577 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | /* |
| 579 | * Reload esp0, LDT and the page table pointer: |
| 580 | */ |
| 581 | tss->rsp0 = next->rsp0; |
| 582 | |
| 583 | /* |
| 584 | * Switch DS and ES. |
| 585 | * This won't pick up thread selector changes, but I guess that is ok. |
| 586 | */ |
H. J. Lu | fd51f66 | 2005-05-01 08:58:48 -0700 | [diff] [blame] | 587 | asm volatile("mov %%es,%0" : "=m" (prev->es)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | if (unlikely(next->es | prev->es)) |
| 589 | loadsegment(es, next->es); |
| 590 | |
H. J. Lu | fd51f66 | 2005-05-01 08:58:48 -0700 | [diff] [blame] | 591 | asm volatile ("mov %%ds,%0" : "=m" (prev->ds)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | if (unlikely(next->ds | prev->ds)) |
| 593 | loadsegment(ds, next->ds); |
| 594 | |
| 595 | load_TLS(next, cpu); |
| 596 | |
| 597 | /* |
| 598 | * Switch FS and GS. |
| 599 | */ |
| 600 | { |
| 601 | unsigned fsindex; |
| 602 | asm volatile("movl %%fs,%0" : "=r" (fsindex)); |
| 603 | /* segment register != 0 always requires a reload. |
| 604 | also reload when it has changed. |
| 605 | when prev process used 64bit base always reload |
| 606 | to avoid an information leak. */ |
| 607 | if (unlikely(fsindex | next->fsindex | prev->fs)) { |
| 608 | loadsegment(fs, next->fsindex); |
| 609 | /* check if the user used a selector != 0 |
| 610 | * if yes clear 64bit base, since overloaded base |
| 611 | * is always mapped to the Null selector |
| 612 | */ |
| 613 | if (fsindex) |
| 614 | prev->fs = 0; |
| 615 | } |
| 616 | /* when next process has a 64bit base use it */ |
| 617 | if (next->fs) |
| 618 | wrmsrl(MSR_FS_BASE, next->fs); |
| 619 | prev->fsindex = fsindex; |
| 620 | } |
| 621 | { |
| 622 | unsigned gsindex; |
| 623 | asm volatile("movl %%gs,%0" : "=r" (gsindex)); |
| 624 | if (unlikely(gsindex | next->gsindex | prev->gs)) { |
| 625 | load_gs_index(next->gsindex); |
| 626 | if (gsindex) |
| 627 | prev->gs = 0; |
| 628 | } |
| 629 | if (next->gs) |
| 630 | wrmsrl(MSR_KERNEL_GS_BASE, next->gs); |
| 631 | prev->gsindex = gsindex; |
| 632 | } |
| 633 | |
Andi Kleen | 0a5ace2 | 2006-10-05 18:47:22 +0200 | [diff] [blame] | 634 | /* Must be after DS reload */ |
| 635 | unlazy_fpu(prev_p); |
| 636 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | /* |
Jan Beulich | 45948d7 | 2006-03-25 16:29:25 +0100 | [diff] [blame] | 638 | * Switch the PDA and FPU contexts. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | */ |
| 640 | prev->userrsp = read_pda(oldrsp); |
| 641 | write_pda(oldrsp, next->userrsp); |
| 642 | write_pda(pcurrent, next_p); |
Andi Kleen | 18bd057 | 2006-04-20 02:36:45 +0200 | [diff] [blame] | 643 | |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 644 | write_pda(kernelstack, |
Andi Kleen | 7b0bda7 | 2006-09-26 10:52:39 +0200 | [diff] [blame] | 645 | (unsigned long)task_stack_page(next_p) + THREAD_SIZE - PDA_STACKOFFSET); |
Arjan van de Ven | 0a42540 | 2006-09-26 10:52:38 +0200 | [diff] [blame] | 646 | #ifdef CONFIG_CC_STACKPROTECTOR |
| 647 | write_pda(stack_canary, next_p->stack_canary); |
| 648 | /* |
| 649 | * Build time only check to make sure the stack_canary is at |
| 650 | * offset 40 in the pda; this is a gcc ABI requirement |
| 651 | */ |
| 652 | BUILD_BUG_ON(offsetof(struct x8664_pda, stack_canary) != 40); |
| 653 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 654 | |
| 655 | /* |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 656 | * Now maybe reload the debug registers and handle I/O bitmaps |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | */ |
Stephane Eranian | d3a4f48 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 658 | if (unlikely((task_thread_info(next_p)->flags & _TIF_WORK_CTXSW)) |
| 659 | || test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) |
| 660 | __switch_to_xtra(prev_p, next_p, tss); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | |
Arjan van de Ven | e07e23e | 2006-09-26 10:52:36 +0200 | [diff] [blame] | 662 | /* If the task has used fpu the last 5 timeslices, just do a full |
| 663 | * restore of the math state immediately to avoid the trap; the |
| 664 | * chances of needing FPU soon are obviously high now |
| 665 | */ |
| 666 | if (next_p->fpu_counter>5) |
| 667 | math_state_restore(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | return prev_p; |
| 669 | } |
| 670 | |
| 671 | /* |
| 672 | * sys_execve() executes a new program. |
| 673 | */ |
| 674 | asmlinkage |
| 675 | long sys_execve(char __user *name, char __user * __user *argv, |
| 676 | char __user * __user *envp, struct pt_regs regs) |
| 677 | { |
| 678 | long error; |
| 679 | char * filename; |
| 680 | |
| 681 | filename = getname(name); |
| 682 | error = PTR_ERR(filename); |
| 683 | if (IS_ERR(filename)) |
| 684 | return error; |
| 685 | error = do_execve(filename, argv, envp, ®s); |
| 686 | if (error == 0) { |
| 687 | task_lock(current); |
| 688 | current->ptrace &= ~PT_DTRACE; |
| 689 | task_unlock(current); |
| 690 | } |
| 691 | putname(filename); |
| 692 | return error; |
| 693 | } |
| 694 | |
| 695 | void set_personality_64bit(void) |
| 696 | { |
| 697 | /* inherit personality from parent */ |
| 698 | |
| 699 | /* Make sure to be in 64bit mode */ |
| 700 | clear_thread_flag(TIF_IA32); |
| 701 | |
| 702 | /* TBD: overwrites user setup. Should have two bits. |
| 703 | But 64bit processes have always behaved this way, |
| 704 | so it's not too bad. The main problem is just that |
| 705 | 32bit childs are affected again. */ |
| 706 | current->personality &= ~READ_IMPLIES_EXEC; |
| 707 | } |
| 708 | |
| 709 | asmlinkage long sys_fork(struct pt_regs *regs) |
| 710 | { |
| 711 | return do_fork(SIGCHLD, regs->rsp, regs, 0, NULL, NULL); |
| 712 | } |
| 713 | |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 714 | asmlinkage long |
| 715 | sys_clone(unsigned long clone_flags, unsigned long newsp, |
| 716 | void __user *parent_tid, void __user *child_tid, struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | { |
| 718 | if (!newsp) |
| 719 | newsp = regs->rsp; |
| 720 | return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid); |
| 721 | } |
| 722 | |
| 723 | /* |
| 724 | * This is trivial, and on the face of it looks like it |
| 725 | * could equally well be done in user mode. |
| 726 | * |
| 727 | * Not so, for quite unobvious reasons - register pressure. |
| 728 | * In user mode vfork() cannot have a stack frame, and if |
| 729 | * done by calling the "clone()" system call directly, you |
| 730 | * do not have enough call-clobbered registers to hold all |
| 731 | * the information you need. |
| 732 | */ |
| 733 | asmlinkage long sys_vfork(struct pt_regs *regs) |
| 734 | { |
| 735 | return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->rsp, regs, 0, |
| 736 | NULL, NULL); |
| 737 | } |
| 738 | |
| 739 | unsigned long get_wchan(struct task_struct *p) |
| 740 | { |
| 741 | unsigned long stack; |
| 742 | u64 fp,rip; |
| 743 | int count = 0; |
| 744 | |
| 745 | if (!p || p == current || p->state==TASK_RUNNING) |
| 746 | return 0; |
Al Viro | 57eafdc | 2006-01-12 01:05:39 -0800 | [diff] [blame] | 747 | stack = (unsigned long)task_stack_page(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 748 | if (p->thread.rsp < stack || p->thread.rsp > stack+THREAD_SIZE) |
| 749 | return 0; |
| 750 | fp = *(u64 *)(p->thread.rsp); |
| 751 | do { |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 752 | if (fp < (unsigned long)stack || |
| 753 | fp > (unsigned long)stack+THREAD_SIZE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | return 0; |
| 755 | rip = *(u64 *)(fp+8); |
| 756 | if (!in_sched_functions(rip)) |
| 757 | return rip; |
| 758 | fp = *(u64 *)fp; |
| 759 | } while (count++ < 16); |
| 760 | return 0; |
| 761 | } |
| 762 | |
| 763 | long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) |
| 764 | { |
| 765 | int ret = 0; |
| 766 | int doit = task == current; |
| 767 | int cpu; |
| 768 | |
| 769 | switch (code) { |
| 770 | case ARCH_SET_GS: |
Suresh Siddha | 8492980 | 2005-06-21 17:14:32 -0700 | [diff] [blame] | 771 | if (addr >= TASK_SIZE_OF(task)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | return -EPERM; |
| 773 | cpu = get_cpu(); |
| 774 | /* handle small bases via the GDT because that's faster to |
| 775 | switch. */ |
| 776 | if (addr <= 0xffffffff) { |
| 777 | set_32bit_tls(task, GS_TLS, addr); |
| 778 | if (doit) { |
| 779 | load_TLS(&task->thread, cpu); |
| 780 | load_gs_index(GS_TLS_SEL); |
| 781 | } |
| 782 | task->thread.gsindex = GS_TLS_SEL; |
| 783 | task->thread.gs = 0; |
| 784 | } else { |
| 785 | task->thread.gsindex = 0; |
| 786 | task->thread.gs = addr; |
| 787 | if (doit) { |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 788 | load_gs_index(0); |
| 789 | ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 790 | } |
| 791 | } |
| 792 | put_cpu(); |
| 793 | break; |
| 794 | case ARCH_SET_FS: |
| 795 | /* Not strictly needed for fs, but do it for symmetry |
| 796 | with gs */ |
Suresh Siddha | 8492980 | 2005-06-21 17:14:32 -0700 | [diff] [blame] | 797 | if (addr >= TASK_SIZE_OF(task)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | return -EPERM; |
| 799 | cpu = get_cpu(); |
| 800 | /* handle small bases via the GDT because that's faster to |
| 801 | switch. */ |
| 802 | if (addr <= 0xffffffff) { |
| 803 | set_32bit_tls(task, FS_TLS, addr); |
| 804 | if (doit) { |
| 805 | load_TLS(&task->thread, cpu); |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 806 | asm volatile("movl %0,%%fs" :: "r"(FS_TLS_SEL)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 807 | } |
| 808 | task->thread.fsindex = FS_TLS_SEL; |
| 809 | task->thread.fs = 0; |
| 810 | } else { |
| 811 | task->thread.fsindex = 0; |
| 812 | task->thread.fs = addr; |
| 813 | if (doit) { |
| 814 | /* set the selector to 0 to not confuse |
| 815 | __switch_to */ |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 816 | asm volatile("movl %0,%%fs" :: "r" (0)); |
| 817 | ret = checking_wrmsrl(MSR_FS_BASE, addr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | } |
| 819 | } |
| 820 | put_cpu(); |
| 821 | break; |
| 822 | case ARCH_GET_FS: { |
| 823 | unsigned long base; |
| 824 | if (task->thread.fsindex == FS_TLS_SEL) |
| 825 | base = read_32bit_tls(task, FS_TLS); |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 826 | else if (doit) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 827 | rdmsrl(MSR_FS_BASE, base); |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 828 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | base = task->thread.fs; |
| 830 | ret = put_user(base, (unsigned long __user *)addr); |
| 831 | break; |
| 832 | } |
| 833 | case ARCH_GET_GS: { |
| 834 | unsigned long base; |
John Blackwood | 97c2803 | 2006-04-07 19:50:25 +0200 | [diff] [blame] | 835 | unsigned gsindex; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 836 | if (task->thread.gsindex == GS_TLS_SEL) |
| 837 | base = read_32bit_tls(task, GS_TLS); |
John Blackwood | 97c2803 | 2006-04-07 19:50:25 +0200 | [diff] [blame] | 838 | else if (doit) { |
| 839 | asm("movl %%gs,%0" : "=r" (gsindex)); |
| 840 | if (gsindex) |
| 841 | rdmsrl(MSR_KERNEL_GS_BASE, base); |
| 842 | else |
| 843 | base = task->thread.gs; |
| 844 | } |
Andi Kleen | a88cde1 | 2005-11-05 17:25:54 +0100 | [diff] [blame] | 845 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | base = task->thread.gs; |
| 847 | ret = put_user(base, (unsigned long __user *)addr); |
| 848 | break; |
| 849 | } |
| 850 | |
| 851 | default: |
| 852 | ret = -EINVAL; |
| 853 | break; |
| 854 | } |
| 855 | |
| 856 | return ret; |
| 857 | } |
| 858 | |
| 859 | long sys_arch_prctl(int code, unsigned long addr) |
| 860 | { |
| 861 | return do_arch_prctl(current, code, addr); |
| 862 | } |
| 863 | |
| 864 | /* |
| 865 | * Capture the user space registers if the task is not running (in user space) |
| 866 | */ |
| 867 | int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) |
| 868 | { |
| 869 | struct pt_regs *pp, ptregs; |
| 870 | |
Al Viro | bb04923 | 2006-01-12 01:05:38 -0800 | [diff] [blame] | 871 | pp = task_pt_regs(tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 872 | |
| 873 | ptregs = *pp; |
| 874 | ptregs.cs &= 0xffff; |
| 875 | ptregs.ss &= 0xffff; |
| 876 | |
| 877 | elf_core_copy_regs(regs, &ptregs); |
| 878 | |
| 879 | return 1; |
| 880 | } |
| 881 | |
| 882 | unsigned long arch_align_stack(unsigned long sp) |
| 883 | { |
Andi Kleen | c16b63e | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 884 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 885 | sp -= get_random_int() % 8192; |
| 886 | return sp & ~0xf; |
| 887 | } |