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 | ||
ca21872e | 10 | #include <linux/elf-randomize.h> |
1da177e4 LT |
11 | #include <linux/compiler.h> |
12 | #include <linux/cpu.h> | |
1da177e4 LT |
13 | #include <linux/sched.h> |
14 | #include <linux/kernel.h> | |
15 | #include <linux/mm.h> | |
638ad34a | 16 | #include <linux/elfcore.h> |
1da177e4 | 17 | #include <linux/smp.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
1da177e4 | 19 | #include <linux/interrupt.h> |
5a62b192 | 20 | #include <linux/tick.h> |
9887a1fc | 21 | #include <linux/personality.h> |
26689452 | 22 | #include <linux/syscalls.h> |
3e86a8c6 | 23 | #include <linux/compat.h> |
860dba45 | 24 | #include <linux/kprobes.h> |
9887a1fc | 25 | #include <linux/random.h> |
3af6fb68 | 26 | #include <linux/module.h> |
0ac27779 | 27 | #include <linux/init_task.h> |
1da177e4 LT |
28 | #include <asm/io.h> |
29 | #include <asm/processor.h> | |
27f6b416 | 30 | #include <asm/vtimer.h> |
f6e38691 | 31 | #include <asm/exec.h> |
1da177e4 | 32 | #include <asm/irq.h> |
f5daba1d | 33 | #include <asm/nmi.h> |
da7f51c1 | 34 | #include <asm/smp.h> |
a0616cde | 35 | #include <asm/switch_to.h> |
e4b8b3f3 | 36 | #include <asm/runtime_instr.h> |
a806170e | 37 | #include "entry.h" |
1da177e4 | 38 | |
94c12cc7 | 39 | asmlinkage void ret_from_fork(void) asm ("ret_from_fork"); |
1da177e4 LT |
40 | |
41 | /* | |
42 | * Return saved PC of a blocked thread. used in kernel/sched. | |
43 | * resume in entry.S does not create a new stack frame, it | |
44 | * just stores the registers %r6-%r15 to the frame given by | |
45 | * schedule. We want to return the address of the caller of | |
46 | * schedule, so we have to walk the backchain one time to | |
47 | * find the frame schedule() store its return address. | |
48 | */ | |
49 | unsigned long thread_saved_pc(struct task_struct *tsk) | |
50 | { | |
eb33c190 | 51 | struct stack_frame *sf, *low, *high; |
1da177e4 | 52 | |
eb33c190 HC |
53 | if (!tsk || !task_stack_page(tsk)) |
54 | return 0; | |
55 | low = task_stack_page(tsk); | |
56 | high = (struct stack_frame *) task_pt_regs(tsk); | |
9cb1ccec | 57 | sf = (struct stack_frame *) tsk->thread.ksp; |
eb33c190 HC |
58 | if (sf <= low || sf > high) |
59 | return 0; | |
9cb1ccec | 60 | sf = (struct stack_frame *) sf->back_chain; |
eb33c190 HC |
61 | if (sf <= low || sf > high) |
62 | return 0; | |
1da177e4 LT |
63 | return sf->gprs[8]; |
64 | } | |
65 | ||
7a5388de | 66 | extern void kernel_thread_starter(void); |
1da177e4 | 67 | |
1da177e4 LT |
68 | /* |
69 | * Free current thread data structures etc.. | |
70 | */ | |
e6464694 | 71 | void exit_thread(struct task_struct *tsk) |
1da177e4 | 72 | { |
e6464694 JS |
73 | if (tsk == current) |
74 | exit_thread_runtime_instr(); | |
1da177e4 LT |
75 | } |
76 | ||
77 | void flush_thread(void) | |
78 | { | |
1da177e4 LT |
79 | } |
80 | ||
81 | void release_thread(struct task_struct *dead_task) | |
82 | { | |
83 | } | |
84 | ||
6a039eab HB |
85 | void arch_release_task_struct(struct task_struct *tsk) |
86 | { | |
155e839a HB |
87 | } |
88 | ||
89 | int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) | |
90 | { | |
9977e886 HB |
91 | /* |
92 | * Save the floating-point or vector register state of the current | |
b5510d9b HB |
93 | * task and set the CIF_FPU flag to lazy restore the FPU register |
94 | * state when returning to user space. | |
9977e886 | 95 | */ |
d0164ee2 | 96 | save_fpu_regs(); |
b5510d9b | 97 | |
3f6813b9 MS |
98 | memcpy(dst, src, arch_task_struct_size); |
99 | dst->thread.fpu.regs = dst->thread.fpu.fprs; | |
155e839a | 100 | return 0; |
6a039eab | 101 | } |
6a039eab | 102 | |
6f2c55b8 | 103 | int copy_thread(unsigned long clone_flags, unsigned long new_stackp, |
afa86fc4 | 104 | unsigned long arg, struct task_struct *p) |
1da177e4 | 105 | { |
5168ce2c | 106 | struct thread_info *ti; |
cbdc2292 HC |
107 | struct fake_frame |
108 | { | |
109 | struct stack_frame sf; | |
110 | struct pt_regs childregs; | |
111 | } *frame; | |
112 | ||
113 | frame = container_of(task_pt_regs(p), struct fake_frame, childregs); | |
114 | p->thread.ksp = (unsigned long) frame; | |
f9a7e025 AV |
115 | /* Save access registers to new thread structure. */ |
116 | save_access_regs(&p->thread.acrs[0]); | |
117 | /* start new process with ar4 pointing to the correct address space */ | |
118 | p->thread.mm_segment = get_fs(); | |
119 | /* Don't copy debug registers */ | |
120 | memset(&p->thread.per_user, 0, sizeof(p->thread.per_user)); | |
121 | memset(&p->thread.per_event, 0, sizeof(p->thread.per_event)); | |
122 | clear_tsk_thread_flag(p, TIF_SINGLE_STEP); | |
f9a7e025 AV |
123 | /* Initialize per thread user and system timer values */ |
124 | ti = task_thread_info(p); | |
125 | ti->user_timer = 0; | |
126 | ti->system_timer = 0; | |
1da177e4 | 127 | |
f9a7e025 | 128 | frame->sf.back_chain = 0; |
cbdc2292 HC |
129 | /* new return point is ret_from_fork */ |
130 | frame->sf.gprs[8] = (unsigned long) ret_from_fork; | |
cbdc2292 HC |
131 | /* fake return stack for resume(), don't go back to schedule */ |
132 | frame->sf.gprs[9] = (unsigned long) frame; | |
1da177e4 | 133 | |
f9a7e025 | 134 | /* Store access registers to kernel stack of new process. */ |
87f1ca8f | 135 | if (unlikely(p->flags & PF_KTHREAD)) { |
f9a7e025 AV |
136 | /* kernel thread */ |
137 | memset(&frame->childregs, 0, sizeof(struct pt_regs)); | |
e258d719 | 138 | frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_DAT | |
f9a7e025 | 139 | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; |
fecc868a | 140 | frame->childregs.psw.addr = |
f9a7e025 AV |
141 | (unsigned long) kernel_thread_starter; |
142 | frame->childregs.gprs[9] = new_stackp; /* function */ | |
143 | frame->childregs.gprs[10] = arg; | |
144 | frame->childregs.gprs[11] = (unsigned long) do_exit; | |
145 | frame->childregs.orig_gpr2 = -1; | |
146 | ||
147 | return 0; | |
148 | } | |
87f1ca8f | 149 | frame->childregs = *current_pt_regs(); |
f9a7e025 | 150 | frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */ |
d3a73acb | 151 | frame->childregs.flags = 0; |
87f1ca8f AV |
152 | if (new_stackp) |
153 | frame->childregs.gprs[15] = new_stackp; | |
1da177e4 | 154 | |
e4b8b3f3 JG |
155 | /* Don't copy runtime instrumentation info */ |
156 | p->thread.ri_cb = NULL; | |
e4b8b3f3 JG |
157 | frame->childregs.psw.mask &= ~PSW_MASK_RI; |
158 | ||
1da177e4 LT |
159 | /* Set a new TLS ? */ |
160 | if (clone_flags & CLONE_SETTLS) { | |
87f1ca8f | 161 | unsigned long tls = frame->childregs.gprs[6]; |
7757591a | 162 | if (is_compat_task()) { |
87f1ca8f | 163 | p->thread.acrs[0] = (unsigned int)tls; |
1da177e4 | 164 | } else { |
87f1ca8f AV |
165 | p->thread.acrs[0] = (unsigned int)(tls >> 32); |
166 | p->thread.acrs[1] = (unsigned int)tls; | |
1da177e4 LT |
167 | } |
168 | } | |
cbdc2292 | 169 | return 0; |
1da177e4 LT |
170 | } |
171 | ||
03ff9a23 MS |
172 | asmlinkage void execve_tail(void) |
173 | { | |
904818e2 | 174 | current->thread.fpu.fpc = 0; |
e47994dd | 175 | asm volatile("sfpc %0" : : "d" (0)); |
1da177e4 LT |
176 | } |
177 | ||
1da177e4 LT |
178 | /* |
179 | * fill in the FPU structure for a core dump. | |
180 | */ | |
181 | int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs) | |
182 | { | |
d0164ee2 | 183 | save_fpu_regs(); |
9977e886 HB |
184 | fpregs->fpc = current->thread.fpu.fpc; |
185 | fpregs->pad = 0; | |
b5510d9b | 186 | if (MACHINE_HAS_VX) |
9977e886 HB |
187 | convert_vx_to_fp((freg_t *)&fpregs->fprs, |
188 | current->thread.fpu.vxrs); | |
189 | else | |
190 | memcpy(&fpregs->fprs, current->thread.fpu.fprs, | |
191 | sizeof(fpregs->fprs)); | |
1da177e4 LT |
192 | return 1; |
193 | } | |
1485c5c8 | 194 | EXPORT_SYMBOL(dump_fpu); |
1da177e4 | 195 | |
1da177e4 LT |
196 | unsigned long get_wchan(struct task_struct *p) |
197 | { | |
198 | struct stack_frame *sf, *low, *high; | |
199 | unsigned long return_address; | |
200 | int count; | |
201 | ||
30af7120 | 202 | if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p)) |
1da177e4 | 203 | return 0; |
30af7120 AV |
204 | low = task_stack_page(p); |
205 | high = (struct stack_frame *) task_pt_regs(p); | |
9cb1ccec | 206 | sf = (struct stack_frame *) p->thread.ksp; |
1da177e4 LT |
207 | if (sf <= low || sf > high) |
208 | return 0; | |
209 | for (count = 0; count < 16; count++) { | |
9cb1ccec | 210 | sf = (struct stack_frame *) sf->back_chain; |
1da177e4 LT |
211 | if (sf <= low || sf > high) |
212 | return 0; | |
9cb1ccec | 213 | return_address = sf->gprs[8]; |
1da177e4 LT |
214 | if (!in_sched_functions(return_address)) |
215 | return return_address; | |
216 | } | |
217 | return 0; | |
218 | } | |
9887a1fc HC |
219 | |
220 | unsigned long arch_align_stack(unsigned long sp) | |
221 | { | |
222 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) | |
223 | sp -= get_random_int() & ~PAGE_MASK; | |
224 | return sp & ~0xf; | |
225 | } | |
33519182 HC |
226 | |
227 | static inline unsigned long brk_rnd(void) | |
228 | { | |
c7e8b2c2 | 229 | return (get_random_int() & BRK_RND_MASK) << PAGE_SHIFT; |
33519182 HC |
230 | } |
231 | ||
232 | unsigned long arch_randomize_brk(struct mm_struct *mm) | |
233 | { | |
9efe4f29 | 234 | unsigned long ret; |
33519182 | 235 | |
9efe4f29 MS |
236 | ret = PAGE_ALIGN(mm->brk + brk_rnd()); |
237 | return (ret > mm->brk) ? ret : mm->brk; | |
33519182 | 238 | } |