xref: /openbmc/linux/arch/sparc/kernel/syscalls.S (revision 3e3511b3c8a5ff68ef7cd3dee8ac9dd9cfe4b2aa)
1/* SPDX-License-Identifier: GPL-2.0 */
2	/* SunOS's execv() call only specifies the argv argument, the
3	 * environment settings are the same as the calling processes.
4	 */
5sys64_execve:
6	set	sys_execve, %g1
7	jmpl	%g1, %g0
8	 flushw
9
10sys64_execveat:
11	set	sys_execveat, %g1
12	jmpl	%g1, %g0
13	 flushw
14
15#ifdef CONFIG_COMPAT
16sunos_execv:
17	mov	%g0, %o2
18sys32_execve:
19	set	compat_sys_execve, %g1
20	jmpl	%g1, %g0
21	 flushw
22
23sys32_execveat:
24	set	compat_sys_execveat, %g1
25	jmpl	%g1, %g0
26	 flushw
27#endif
28
29	.align	32
30sys_nis_syscall:
31	ba,pt	%xcc, c_sys_nis_syscall
32	 add	%sp, PTREGS_OFF, %o0
33sys_memory_ordering:
34	ba,pt	%xcc, sparc_memory_ordering
35	 add	%sp, PTREGS_OFF, %o1
36#ifdef CONFIG_COMPAT
37sys32_sigstack:
38	ba,pt	%xcc, do_sys32_sigstack
39	 mov	%i6, %o2
40#endif
41	.align	32
42#ifdef CONFIG_COMPAT
43sys32_sigreturn:
44	add	%sp, PTREGS_OFF, %o0
45	call	do_sigreturn32
46	 add	%o7, 1f-.-4, %o7
47	nop
48#endif
49sys_rt_sigreturn:
50	add	%sp, PTREGS_OFF, %o0
51	call	do_rt_sigreturn
52	 add	%o7, 1f-.-4, %o7
53	nop
54#ifdef CONFIG_COMPAT
55sys32_rt_sigreturn:
56	add	%sp, PTREGS_OFF, %o0
57	call	do_rt_sigreturn32
58	 add	%o7, 1f-.-4, %o7
59	nop
60#endif
61	.align	32
621:	ldx	[%g6 + TI_FLAGS], %l5
63	andcc	%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
64	be,pt	%icc, rtrap
65	 nop
66	call	syscall_trace_leave
67	 add	%sp, PTREGS_OFF, %o0
68	ba,pt	%xcc, rtrap
69	 nop
70
71	/* This is how fork() was meant to be done, 8 instruction entry.
72	 *
73	 * I questioned the following code briefly, let me clear things
74	 * up so you must not reason on it like I did.
75	 *
76	 * Know the fork_kpsr etc. we use in the sparc32 port?  We don't
77	 * need it here because the only piece of window state we copy to
78	 * the child is the CWP register.  Even if the parent sleeps,
79	 * we are safe because we stuck it into pt_regs of the parent
80	 * so it will not change.
81	 *
82	 * XXX This raises the question, whether we can do the same on
83	 * XXX sparc32 to get rid of fork_kpsr _and_ fork_kwim.  The
84	 * XXX answer is yes.  We stick fork_kpsr in UREG_G0 and
85	 * XXX fork_kwim in UREG_G1 (global registers are considered
86	 * XXX volatile across a system call in the sparc ABI I think
87	 * XXX if it isn't we can use regs->y instead, anyone who depends
88	 * XXX upon the Y register being preserved across a fork deserves
89	 * XXX to lose).
90	 *
91	 * In fact we should take advantage of that fact for other things
92	 * during system calls...
93	 */
94	.align	32
95sys_vfork: /* Under Linux, vfork and fork are just special cases of clone. */
96	sethi	%hi(0x4000 | 0x0100 | SIGCHLD), %o0
97	or	%o0, %lo(0x4000 | 0x0100 | SIGCHLD), %o0
98	ba,pt	%xcc, sys_clone
99sys_fork:
100	 clr	%o1
101	mov	SIGCHLD, %o0
102sys_clone:
103	flushw
104	movrz	%o1, %fp, %o1
105	mov	0, %o3
106	ba,pt	%xcc, sparc_do_fork
107	 add	%sp, PTREGS_OFF, %o2
108
109	.globl	ret_from_fork
110ret_from_fork:
111	/* Clear current_thread_info()->new_child. */
112	stb	%g0, [%g6 + TI_NEW_CHILD]
113	call	schedule_tail
114	 mov	%g7, %o0
115	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %o0
116	brnz,pt	%o0, ret_sys_call
117	 ldx	[%g6 + TI_FLAGS], %l0
118	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %l1
119	call	%l1
120	 ldx	[%sp + PTREGS_OFF + PT_V9_G2], %o0
121	ba,pt	%xcc, ret_sys_call
122	 mov	0, %o0
123
124	.globl	sparc_exit_group
125	.type	sparc_exit_group,#function
126sparc_exit_group:
127	sethi	%hi(sys_exit_group), %g7
128	ba,pt	%xcc, 1f
129	 or	%g7, %lo(sys_exit_group), %g7
130	.size	sparc_exit_group,.-sparc_exit_group
131
132	.globl	sparc_exit
133	.type	sparc_exit,#function
134sparc_exit:
135	sethi	%hi(sys_exit), %g7
136	or	%g7, %lo(sys_exit), %g7
1371:	rdpr	%pstate, %g2
138	wrpr	%g2, PSTATE_IE, %pstate
139	rdpr	%otherwin, %g1
140	rdpr	%cansave, %g3
141	add	%g3, %g1, %g3
142	wrpr	%g3, 0x0, %cansave
143	wrpr	%g0, 0x0, %otherwin
144	wrpr	%g2, 0x0, %pstate
145	jmpl	%g7, %g0
146	 stb	%g0, [%g6 + TI_WSAVED]
147	.size	sparc_exit,.-sparc_exit
148
149linux_sparc_ni_syscall:
150	sethi	%hi(sys_ni_syscall), %l7
151	ba,pt	%xcc, 4f
152	 or	%l7, %lo(sys_ni_syscall), %l7
153
154linux_syscall_trace32:
155	call	syscall_trace_enter
156	 add	%sp, PTREGS_OFF, %o0
157	brnz,pn	%o0, 3f
158	 mov	-ENOSYS, %o0
159
160	/* Syscall tracing can modify the registers.  */
161	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
162	sethi	%hi(sys_call_table32), %l7
163	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
164	or	%l7, %lo(sys_call_table32), %l7
165	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
166	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
167	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
168	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
169	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
170
171	cmp	%g1, NR_syscalls
172	bgeu,pn	%xcc, 3f
173	 mov	-ENOSYS, %o0
174
175	sll	%g1, 2, %l4
176	srl	%i0, 0, %o0
177	lduw	[%l7 + %l4], %l7
178	srl	%i4, 0, %o4
179	srl	%i1, 0, %o1
180	srl	%i2, 0, %o2
181	ba,pt	%xcc, 5f
182	 srl	%i3, 0, %o3
183
184linux_syscall_trace:
185	call	syscall_trace_enter
186	 add	%sp, PTREGS_OFF, %o0
187	brnz,pn	%o0, 3f
188	 mov	-ENOSYS, %o0
189
190	/* Syscall tracing can modify the registers.  */
191	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
192	sethi	%hi(sys_call_table64), %l7
193	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
194	or	%l7, %lo(sys_call_table64), %l7
195	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
196	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
197	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
198	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
199	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
200
201	cmp	%g1, NR_syscalls
202	bgeu,pn	%xcc, 3f
203	 mov	-ENOSYS, %o0
204
205	sll	%g1, 2, %l4
206	mov	%i0, %o0
207	lduw	[%l7 + %l4], %l7
208	mov	%i1, %o1
209	mov	%i2, %o2
210	mov	%i3, %o3
211	b,pt	%xcc, 2f
212	 mov	%i4, %o4
213
214
215	/* Linux 32-bit system calls enter here... */
216	.align	32
217	.globl	linux_sparc_syscall32
218linux_sparc_syscall32:
219	/* Direct access to user regs, much faster. */
220	cmp	%g1, NR_syscalls			! IEU1	Group
221	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
222	 srl	%i0, 0, %o0				! IEU0
223	sll	%g1, 2, %l4				! IEU0	Group
224	srl	%i4, 0, %o4				! IEU1
225	lduw	[%l7 + %l4], %l7			! Load
226	srl	%i1, 0, %o1				! IEU0	Group
227	ldx	[%g6 + TI_FLAGS], %l0		! Load
228
229	srl	%i3, 0, %o3				! IEU0
230	srl	%i2, 0, %o2				! IEU0	Group
231	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
232	bne,pn	%icc, linux_syscall_trace32		! CTI
233	 mov	%i0, %l5				! IEU1
2345:	call	%l7					! CTI	Group brk forced
235	 srl	%i5, 0, %o5				! IEU1
236	ba,pt	%xcc, 3f
237	 sra	%o0, 0, %o0
238
239	/* Linux native system calls enter here... */
240	.align	32
241	.globl	linux_sparc_syscall
242linux_sparc_syscall:
243	/* Direct access to user regs, much faster. */
244	cmp	%g1, NR_syscalls			! IEU1	Group
245	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
246	 mov	%i0, %o0				! IEU0
247	sll	%g1, 2, %l4				! IEU0	Group
248	mov	%i1, %o1				! IEU1
249	lduw	[%l7 + %l4], %l7			! Load
2504:	mov	%i2, %o2				! IEU0	Group
251	ldx	[%g6 + TI_FLAGS], %l0		! Load
252
253	mov	%i3, %o3				! IEU1
254	mov	%i4, %o4				! IEU0	Group
255	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
256	bne,pn	%icc, linux_syscall_trace		! CTI	Group
257	 mov	%i0, %l5				! IEU0
2582:	call	%l7					! CTI	Group brk forced
259	 mov	%i5, %o5				! IEU0
260	nop
261
2623:	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
263ret_sys_call:
264	ldx	[%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
265	mov	%ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
266	sllx	%g2, 32, %g2
267
268	cmp	%o0, -ERESTART_RESTARTBLOCK
269	bgeu,pn	%xcc, 1f
270	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
271	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
272
2732:
274	/* System call success, clear Carry condition code. */
275	andn	%g3, %g2, %g3
2763:
277	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
278	bne,pn	%icc, linux_syscall_trace2
279	 add	%l1, 0x4, %l2			! npc = npc+4
280	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
281	ba,pt	%xcc, rtrap
282	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
283
2841:
285	/* Check if force_successful_syscall_return()
286	 * was invoked.
287	 */
288	ldub	[%g6 + TI_SYS_NOERROR], %l2
289	brnz,pn %l2, 2b
290	 ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
291	/* System call failure, set Carry condition code.
292	 * Also, get abs(errno) to return to the process.
293	 */
294	sub	%g0, %o0, %o0
295	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
296	ba,pt	%xcc, 3b
297	 or	%g3, %g2, %g3
298
299linux_syscall_trace2:
300	call	syscall_trace_leave
301	 add	%sp, PTREGS_OFF, %o0
302	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
303	ba,pt	%xcc, rtrap
304	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
305