Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
cbdc2292 | 2 | * This file handles the architecture dependent parts of process handling. |
1da177e4 | 3 | * |
a53c8fab | 4 | * Copyright IBM Corp. 1999, 2009 |
cbdc2292 HC |
5 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, |
6 | * Hartmut Penner <hp@de.ibm.com>, | |
7 | * Denis Joseph Barrow, | |
1da177e4 LT |
8 | */ |
9 | ||
1da177e4 LT |
10 | #include <linux/compiler.h> |
11 | #include <linux/cpu.h> | |
1da177e4 LT |
12 | #include <linux/sched.h> |
13 | #include <linux/kernel.h> | |
14 | #include <linux/mm.h> | |
638ad34a | 15 | #include <linux/elfcore.h> |
1da177e4 | 16 | #include <linux/smp.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
1da177e4 | 18 | #include <linux/interrupt.h> |
5a62b192 | 19 | #include <linux/tick.h> |
9887a1fc | 20 | #include <linux/personality.h> |
26689452 | 21 | #include <linux/syscalls.h> |
3e86a8c6 | 22 | #include <linux/compat.h> |
860dba45 | 23 | #include <linux/kprobes.h> |
9887a1fc | 24 | #include <linux/random.h> |
3af6fb68 | 25 | #include <linux/module.h> |
1da177e4 LT |
26 | #include <asm/io.h> |
27 | #include <asm/processor.h> | |
27f6b416 | 28 | #include <asm/vtimer.h> |
f6e38691 | 29 | #include <asm/exec.h> |
1da177e4 | 30 | #include <asm/irq.h> |
f5daba1d | 31 | #include <asm/nmi.h> |
da7f51c1 | 32 | #include <asm/smp.h> |
a0616cde | 33 | #include <asm/switch_to.h> |
e4b8b3f3 | 34 | #include <asm/runtime_instr.h> |
a806170e | 35 | #include "entry.h" |
1da177e4 | 36 | |
94c12cc7 | 37 | asmlinkage void ret_from_fork(void) asm ("ret_from_fork"); |
1da177e4 LT |
38 | |
39 | /* | |
40 | * Return saved PC of a blocked thread. used in kernel/sched. | |
41 | * resume in entry.S does not create a new stack frame, it | |
42 | * just stores the registers %r6-%r15 to the frame given by | |
43 | * schedule. We want to return the address of the caller of | |
44 | * schedule, so we have to walk the backchain one time to | |
45 | * find the frame schedule() store its return address. | |
46 | */ | |
47 | unsigned long thread_saved_pc(struct task_struct *tsk) | |
48 | { | |
eb33c190 | 49 | struct stack_frame *sf, *low, *high; |
1da177e4 | 50 | |
eb33c190 HC |
51 | if (!tsk || !task_stack_page(tsk)) |
52 | return 0; | |
53 | low = task_stack_page(tsk); | |
54 | high = (struct stack_frame *) task_pt_regs(tsk); | |
55 | sf = (struct stack_frame *) (tsk->thread.ksp & PSW_ADDR_INSN); | |
56 | if (sf <= low || sf > high) | |
57 | return 0; | |
58 | sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN); | |
59 | if (sf <= low || sf > high) | |
60 | return 0; | |
1da177e4 LT |
61 | return sf->gprs[8]; |
62 | } | |
63 | ||
52c00659 | 64 | void arch_cpu_idle(void) |
1da177e4 | 65 | { |
77fa2245 HC |
66 | local_mcck_disable(); |
67 | if (test_thread_flag(TIF_MCCK_PENDING)) { | |
68 | local_mcck_enable(); | |
69 | local_irq_enable(); | |
77fa2245 HC |
70 | return; |
71 | } | |
4c1051e3 | 72 | /* Halt the cpu and keep track of cpu time accounting. */ |
9cfb9b3c | 73 | vtime_stop_cpu(); |
0587d409 | 74 | local_irq_enable(); |
1da177e4 LT |
75 | } |
76 | ||
52c00659 | 77 | void arch_cpu_idle_exit(void) |
1da177e4 | 78 | { |
52c00659 TG |
79 | if (test_thread_flag(TIF_MCCK_PENDING)) |
80 | s390_handle_mcck(); | |
81 | } | |
82 | ||
83 | void arch_cpu_idle_dead(void) | |
84 | { | |
85 | cpu_die(); | |
1da177e4 LT |
86 | } |
87 | ||
860dba45 | 88 | extern void __kprobes kernel_thread_starter(void); |
1da177e4 | 89 | |
1da177e4 LT |
90 | /* |
91 | * Free current thread data structures etc.. | |
92 | */ | |
93 | void exit_thread(void) | |
94 | { | |
e4b8b3f3 | 95 | exit_thread_runtime_instr(); |
1da177e4 LT |
96 | } |
97 | ||
98 | void flush_thread(void) | |
99 | { | |
1da177e4 LT |
100 | } |
101 | ||
102 | void release_thread(struct task_struct *dead_task) | |
103 | { | |
104 | } | |
105 | ||
6f2c55b8 | 106 | int copy_thread(unsigned long clone_flags, unsigned long new_stackp, |
afa86fc4 | 107 | unsigned long arg, struct task_struct *p) |
1da177e4 | 108 | { |
5168ce2c | 109 | struct thread_info *ti; |
cbdc2292 HC |
110 | struct fake_frame |
111 | { | |
112 | struct stack_frame sf; | |
113 | struct pt_regs childregs; | |
114 | } *frame; | |
115 | ||
116 | frame = container_of(task_pt_regs(p), struct fake_frame, childregs); | |
117 | p->thread.ksp = (unsigned long) frame; | |
f9a7e025 AV |
118 | /* Save access registers to new thread structure. */ |
119 | save_access_regs(&p->thread.acrs[0]); | |
120 | /* start new process with ar4 pointing to the correct address space */ | |
121 | p->thread.mm_segment = get_fs(); | |
122 | /* Don't copy debug registers */ | |
123 | memset(&p->thread.per_user, 0, sizeof(p->thread.per_user)); | |
124 | memset(&p->thread.per_event, 0, sizeof(p->thread.per_event)); | |
125 | clear_tsk_thread_flag(p, TIF_SINGLE_STEP); | |
126 | clear_tsk_thread_flag(p, TIF_PER_TRAP); | |
127 | /* Initialize per thread user and system timer values */ | |
128 | ti = task_thread_info(p); | |
129 | ti->user_timer = 0; | |
130 | ti->system_timer = 0; | |
1da177e4 | 131 | |
f9a7e025 | 132 | frame->sf.back_chain = 0; |
cbdc2292 HC |
133 | /* new return point is ret_from_fork */ |
134 | frame->sf.gprs[8] = (unsigned long) ret_from_fork; | |
cbdc2292 HC |
135 | /* fake return stack for resume(), don't go back to schedule */ |
136 | frame->sf.gprs[9] = (unsigned long) frame; | |
1da177e4 | 137 | |
f9a7e025 | 138 | /* Store access registers to kernel stack of new process. */ |
87f1ca8f | 139 | if (unlikely(p->flags & PF_KTHREAD)) { |
f9a7e025 AV |
140 | /* kernel thread */ |
141 | memset(&frame->childregs, 0, sizeof(struct pt_regs)); | |
142 | frame->childregs.psw.mask = psw_kernel_bits | PSW_MASK_DAT | | |
143 | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; | |
144 | frame->childregs.psw.addr = PSW_ADDR_AMODE | | |
145 | (unsigned long) kernel_thread_starter; | |
146 | frame->childregs.gprs[9] = new_stackp; /* function */ | |
147 | frame->childregs.gprs[10] = arg; | |
148 | frame->childregs.gprs[11] = (unsigned long) do_exit; | |
149 | frame->childregs.orig_gpr2 = -1; | |
150 | ||
151 | return 0; | |
152 | } | |
87f1ca8f | 153 | frame->childregs = *current_pt_regs(); |
f9a7e025 | 154 | frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */ |
87f1ca8f AV |
155 | if (new_stackp) |
156 | frame->childregs.gprs[15] = new_stackp; | |
1da177e4 | 157 | |
e4b8b3f3 JG |
158 | /* Don't copy runtime instrumentation info */ |
159 | p->thread.ri_cb = NULL; | |
160 | p->thread.ri_signum = 0; | |
161 | frame->childregs.psw.mask &= ~PSW_MASK_RI; | |
162 | ||
347a8dc3 | 163 | #ifndef CONFIG_64BIT |
cbdc2292 | 164 | /* |
1da177e4 LT |
165 | * save fprs to current->thread.fp_regs to merge them with |
166 | * the emulated registers and then copy the result to the child. | |
167 | */ | |
168 | save_fp_regs(¤t->thread.fp_regs); | |
169 | memcpy(&p->thread.fp_regs, ¤t->thread.fp_regs, | |
170 | sizeof(s390_fp_regs)); | |
1da177e4 LT |
171 | /* Set a new TLS ? */ |
172 | if (clone_flags & CLONE_SETTLS) | |
87f1ca8f | 173 | p->thread.acrs[0] = frame->childregs.gprs[6]; |
347a8dc3 | 174 | #else /* CONFIG_64BIT */ |
1da177e4 LT |
175 | /* Save the fpu registers to new thread structure. */ |
176 | save_fp_regs(&p->thread.fp_regs); | |
1da177e4 LT |
177 | /* Set a new TLS ? */ |
178 | if (clone_flags & CLONE_SETTLS) { | |
87f1ca8f | 179 | unsigned long tls = frame->childregs.gprs[6]; |
7757591a | 180 | if (is_compat_task()) { |
87f1ca8f | 181 | p->thread.acrs[0] = (unsigned int)tls; |
1da177e4 | 182 | } else { |
87f1ca8f AV |
183 | p->thread.acrs[0] = (unsigned int)(tls >> 32); |
184 | p->thread.acrs[1] = (unsigned int)tls; | |
1da177e4 LT |
185 | } |
186 | } | |
347a8dc3 | 187 | #endif /* CONFIG_64BIT */ |
cbdc2292 | 188 | return 0; |
1da177e4 LT |
189 | } |
190 | ||
03ff9a23 MS |
191 | asmlinkage void execve_tail(void) |
192 | { | |
03ff9a23 MS |
193 | current->thread.fp_regs.fpc = 0; |
194 | if (MACHINE_HAS_IEEE) | |
195 | asm volatile("sfpc %0,%0" : : "d" (0)); | |
1da177e4 LT |
196 | } |
197 | ||
1da177e4 LT |
198 | /* |
199 | * fill in the FPU structure for a core dump. | |
200 | */ | |
201 | int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs) | |
202 | { | |
347a8dc3 | 203 | #ifndef CONFIG_64BIT |
cbdc2292 | 204 | /* |
1da177e4 LT |
205 | * save fprs to current->thread.fp_regs to merge them with |
206 | * the emulated registers and then copy the result to the dump. | |
207 | */ | |
208 | save_fp_regs(¤t->thread.fp_regs); | |
209 | memcpy(fpregs, ¤t->thread.fp_regs, sizeof(s390_fp_regs)); | |
347a8dc3 | 210 | #else /* CONFIG_64BIT */ |
1da177e4 | 211 | save_fp_regs(fpregs); |
347a8dc3 | 212 | #endif /* CONFIG_64BIT */ |
1da177e4 LT |
213 | return 1; |
214 | } | |
1485c5c8 | 215 | EXPORT_SYMBOL(dump_fpu); |
1da177e4 | 216 | |
1da177e4 LT |
217 | unsigned long get_wchan(struct task_struct *p) |
218 | { | |
219 | struct stack_frame *sf, *low, *high; | |
220 | unsigned long return_address; | |
221 | int count; | |
222 | ||
30af7120 | 223 | if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p)) |
1da177e4 | 224 | return 0; |
30af7120 AV |
225 | low = task_stack_page(p); |
226 | high = (struct stack_frame *) task_pt_regs(p); | |
1da177e4 LT |
227 | sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN); |
228 | if (sf <= low || sf > high) | |
229 | return 0; | |
230 | for (count = 0; count < 16; count++) { | |
231 | sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN); | |
232 | if (sf <= low || sf > high) | |
233 | return 0; | |
234 | return_address = sf->gprs[8] & PSW_ADDR_INSN; | |
235 | if (!in_sched_functions(return_address)) | |
236 | return return_address; | |
237 | } | |
238 | return 0; | |
239 | } | |
9887a1fc HC |
240 | |
241 | unsigned long arch_align_stack(unsigned long sp) | |
242 | { | |
243 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) | |
244 | sp -= get_random_int() & ~PAGE_MASK; | |
245 | return sp & ~0xf; | |
246 | } | |
33519182 HC |
247 | |
248 | static inline unsigned long brk_rnd(void) | |
249 | { | |
250 | /* 8MB for 32bit, 1GB for 64bit */ | |
251 | if (is_32bit_task()) | |
252 | return (get_random_int() & 0x7ffUL) << PAGE_SHIFT; | |
253 | else | |
254 | return (get_random_int() & 0x3ffffUL) << PAGE_SHIFT; | |
255 | } | |
256 | ||
257 | unsigned long arch_randomize_brk(struct mm_struct *mm) | |
258 | { | |
259 | unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd()); | |
260 | ||
261 | if (ret < mm->brk) | |
262 | return mm->brk; | |
263 | return ret; | |
264 | } | |
d2c9dfcc HC |
265 | |
266 | unsigned long randomize_et_dyn(unsigned long base) | |
267 | { | |
268 | unsigned long ret = PAGE_ALIGN(base + brk_rnd()); | |
269 | ||
270 | if (!(current->flags & PF_RANDOMIZE)) | |
271 | return base; | |
272 | if (ret < base) | |
273 | return base; | |
274 | return ret; | |
275 | } |