xref: /openbmc/linux/arch/sparc/kernel/syscalls.S (revision fd589a8f)
1	/* SunOS's execv() call only specifies the argv argument, the
2	 * environment settings are the same as the calling processes.
3	 */
4sys_execve:
5	sethi	%hi(sparc_execve), %g1
6	ba,pt	%xcc, execve_merge
7	 or	%g1, %lo(sparc_execve), %g1
8
9#ifdef CONFIG_COMPAT
10sunos_execv:
11	stx	%g0, [%sp + PTREGS_OFF + PT_V9_I2]
12sys32_execve:
13	sethi	%hi(sparc32_execve), %g1
14	or	%g1, %lo(sparc32_execve), %g1
15#endif
16
17execve_merge:
18	flushw
19	jmpl	%g1, %g0
20	 add	%sp, PTREGS_OFF, %o0
21
22	.align	32
23sys_sparc_pipe:
24	ba,pt	%xcc, sys_sparc_pipe_real
25	 add	%sp, PTREGS_OFF, %o0
26sys_nis_syscall:
27	ba,pt	%xcc, c_sys_nis_syscall
28	 add	%sp, PTREGS_OFF, %o0
29sys_memory_ordering:
30	ba,pt	%xcc, sparc_memory_ordering
31	 add	%sp, PTREGS_OFF, %o1
32sys_sigaltstack:
33	ba,pt	%xcc, do_sigaltstack
34	 add	%i6, STACK_BIAS, %o2
35#ifdef CONFIG_COMPAT
36sys32_sigstack:
37	ba,pt	%xcc, do_sys32_sigstack
38	 mov	%i6, %o2
39sys32_sigaltstack:
40	ba,pt	%xcc, do_sys32_sigaltstack
41	 mov	%i6, %o2
42#endif
43	.align	32
44#ifdef CONFIG_COMPAT
45sys32_sigreturn:
46	add	%sp, PTREGS_OFF, %o0
47	call	do_sigreturn32
48	 add	%o7, 1f-.-4, %o7
49	nop
50#endif
51sys_rt_sigreturn:
52	add	%sp, PTREGS_OFF, %o0
53	call	do_rt_sigreturn
54	 add	%o7, 1f-.-4, %o7
55	nop
56#ifdef CONFIG_COMPAT
57sys32_rt_sigreturn:
58	add	%sp, PTREGS_OFF, %o0
59	call	do_rt_sigreturn32
60	 add	%o7, 1f-.-4, %o7
61	nop
62#endif
63	.align	32
641:	ldx	[%g6 + TI_FLAGS], %l5
65	andcc	%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT), %g0
66	be,pt	%icc, rtrap
67	 nop
68	call	syscall_trace_leave
69	 add	%sp, PTREGS_OFF, %o0
70	ba,pt	%xcc, rtrap
71	 nop
72
73	/* This is how fork() was meant to be done, 8 instruction entry.
74	 *
75	 * I questioned the following code briefly, let me clear things
76	 * up so you must not reason on it like I did.
77	 *
78	 * Know the fork_kpsr etc. we use in the sparc32 port?  We don't
79	 * need it here because the only piece of window state we copy to
80	 * the child is the CWP register.  Even if the parent sleeps,
81	 * we are safe because we stuck it into pt_regs of the parent
82	 * so it will not change.
83	 *
84	 * XXX This raises the question, whether we can do the same on
85	 * XXX sparc32 to get rid of fork_kpsr _and_ fork_kwim.  The
86	 * XXX answer is yes.  We stick fork_kpsr in UREG_G0 and
87	 * XXX fork_kwim in UREG_G1 (global registers are considered
88	 * XXX volatile across a system call in the sparc ABI I think
89	 * XXX if it isn't we can use regs->y instead, anyone who depends
90	 * XXX upon the Y register being preserved across a fork deserves
91	 * XXX to lose).
92	 *
93	 * In fact we should take advantage of that fact for other things
94	 * during system calls...
95	 */
96	.align	32
97sys_vfork: /* Under Linux, vfork and fork are just special cases of clone. */
98	sethi	%hi(0x4000 | 0x0100 | SIGCHLD), %o0
99	or	%o0, %lo(0x4000 | 0x0100 | SIGCHLD), %o0
100	ba,pt	%xcc, sys_clone
101sys_fork:
102	 clr	%o1
103	mov	SIGCHLD, %o0
104sys_clone:
105	flushw
106	movrz	%o1, %fp, %o1
107	mov	0, %o3
108	ba,pt	%xcc, sparc_do_fork
109	 add	%sp, PTREGS_OFF, %o2
110
111	.globl	ret_from_syscall
112ret_from_syscall:
113	/* Clear current_thread_info()->new_child, and
114	 * check performance counter stuff too.
115	 */
116	stb	%g0, [%g6 + TI_NEW_CHILD]
117	ldx	[%g6 + TI_FLAGS], %l0
118	call	schedule_tail
119	 mov	%g7, %o0
120	andcc	%l0, _TIF_PERFCTR, %g0
121	be,pt	%icc, 1f
122	 nop
123	ldx	[%g6 + TI_PCR], %o7
124	wr	%g0, %o7, %pcr
125
126	/* Blackbird errata workaround.  See commentary in
127	 * smp.c:smp_percpu_timer_interrupt() for more
128	 * information.
129	 */
130	ba,pt	%xcc, 99f
131	 nop
132
133	.align	64
13499:	wr	%g0, %g0, %pic
135	rd	%pic, %g0
136
1371:	ba,pt	%xcc, ret_sys_call
138	 ldx	[%sp + PTREGS_OFF + PT_V9_I0], %o0
139
140	.globl	sparc_exit
141	.type	sparc_exit,#function
142sparc_exit:
143	rdpr	%pstate, %g2
144	wrpr	%g2, PSTATE_IE, %pstate
145	rdpr	%otherwin, %g1
146	rdpr	%cansave, %g3
147	add	%g3, %g1, %g3
148	wrpr	%g3, 0x0, %cansave
149	wrpr	%g0, 0x0, %otherwin
150	wrpr	%g2, 0x0, %pstate
151	ba,pt	%xcc, sys_exit
152	 stb	%g0, [%g6 + TI_WSAVED]
153	.size	sparc_exit,.-sparc_exit
154
155linux_sparc_ni_syscall:
156	sethi	%hi(sys_ni_syscall), %l7
157	ba,pt	%xcc, 4f
158	 or	%l7, %lo(sys_ni_syscall), %l7
159
160linux_syscall_trace32:
161	call	syscall_trace_enter
162	 add	%sp, PTREGS_OFF, %o0
163	brnz,pn	%o0, 3f
164	 mov	-ENOSYS, %o0
165	srl	%i0, 0, %o0
166	srl	%i4, 0, %o4
167	srl	%i1, 0, %o1
168	srl	%i2, 0, %o2
169	ba,pt	%xcc, 2f
170	 srl	%i3, 0, %o3
171
172linux_syscall_trace:
173	call	syscall_trace_enter
174	 add	%sp, PTREGS_OFF, %o0
175	brnz,pn	%o0, 3f
176	 mov	-ENOSYS, %o0
177	mov	%i0, %o0
178	mov	%i1, %o1
179	mov	%i2, %o2
180	mov	%i3, %o3
181	b,pt	%xcc, 2f
182	 mov	%i4, %o4
183
184
185	/* Linux 32-bit system calls enter here... */
186	.align	32
187	.globl	linux_sparc_syscall32
188linux_sparc_syscall32:
189	/* Direct access to user regs, much faster. */
190	cmp	%g1, NR_SYSCALLS			! IEU1	Group
191	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
192	 srl	%i0, 0, %o0				! IEU0
193	sll	%g1, 2, %l4				! IEU0	Group
194	srl	%i4, 0, %o4				! IEU1
195	lduw	[%l7 + %l4], %l7			! Load
196	srl	%i1, 0, %o1				! IEU0	Group
197	ldx	[%g6 + TI_FLAGS], %l0		! Load
198
199	srl	%i5, 0, %o5				! IEU1
200	srl	%i2, 0, %o2				! IEU0	Group
201	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT), %g0
202	bne,pn	%icc, linux_syscall_trace32		! CTI
203	 mov	%i0, %l5				! IEU1
204	call	%l7					! CTI	Group brk forced
205	 srl	%i3, 0, %o3				! IEU0
206	ba,a,pt	%xcc, 3f
207
208	/* Linux native system calls enter here... */
209	.align	32
210	.globl	linux_sparc_syscall
211linux_sparc_syscall:
212	/* Direct access to user regs, much faster. */
213	cmp	%g1, NR_SYSCALLS			! IEU1	Group
214	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
215	 mov	%i0, %o0				! IEU0
216	sll	%g1, 2, %l4				! IEU0	Group
217	mov	%i1, %o1				! IEU1
218	lduw	[%l7 + %l4], %l7			! Load
2194:	mov	%i2, %o2				! IEU0	Group
220	ldx	[%g6 + TI_FLAGS], %l0		! Load
221
222	mov	%i3, %o3				! IEU1
223	mov	%i4, %o4				! IEU0	Group
224	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT), %g0
225	bne,pn	%icc, linux_syscall_trace		! CTI	Group
226	 mov	%i0, %l5				! IEU0
2272:	call	%l7					! CTI	Group brk forced
228	 mov	%i5, %o5				! IEU0
229	nop
230
2313:	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
232ret_sys_call:
233	ldx	[%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
234	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
235	sra	%o0, 0, %o0
236	mov	%ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
237	sllx	%g2, 32, %g2
238
239	/* Check if force_successful_syscall_return()
240	 * was invoked.
241	 */
242	ldub	[%g6 + TI_SYS_NOERROR], %l2
243	brnz,a,pn %l2, 80f
244	 stb	%g0, [%g6 + TI_SYS_NOERROR]
245
246	cmp	%o0, -ERESTART_RESTARTBLOCK
247	bgeu,pn	%xcc, 1f
248	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT), %l6
24980:
250	/* System call success, clear Carry condition code. */
251	andn	%g3, %g2, %g3
252	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
253	bne,pn	%icc, linux_syscall_trace2
254	 add	%l1, 0x4, %l2			! npc = npc+4
255	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
256	ba,pt	%xcc, rtrap
257	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
258
2591:
260	/* System call failure, set Carry condition code.
261	 * Also, get abs(errno) to return to the process.
262	 */
263	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT), %l6
264	sub	%g0, %o0, %o0
265	or	%g3, %g2, %g3
266	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
267	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
268	bne,pn	%icc, linux_syscall_trace2
269	 add	%l1, 0x4, %l2			! npc = npc+4
270	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
271
272	b,pt	%xcc, rtrap
273	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
274linux_syscall_trace2:
275	call	syscall_trace_leave
276	 add	%sp, PTREGS_OFF, %o0
277	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
278	ba,pt	%xcc, rtrap
279	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
280