xref: /openbmc/linux/arch/sparc/kernel/syscalls.S (revision 6c33a6f4)
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
30#ifdef CONFIG_COMPAT
31sys32_sigstack:
32	ba,pt	%xcc, do_sys32_sigstack
33	 mov	%i6, %o2
34#endif
35	.align	32
36#ifdef CONFIG_COMPAT
37sys32_sigreturn:
38	add	%sp, PTREGS_OFF, %o0
39	call	do_sigreturn32
40	 add	%o7, 1f-.-4, %o7
41	nop
42#endif
43sys_rt_sigreturn:
44	add	%sp, PTREGS_OFF, %o0
45	call	do_rt_sigreturn
46	 add	%o7, 1f-.-4, %o7
47	nop
48#ifdef CONFIG_COMPAT
49sys32_rt_sigreturn:
50	add	%sp, PTREGS_OFF, %o0
51	call	do_rt_sigreturn32
52	 add	%o7, 1f-.-4, %o7
53	nop
54#endif
55	.align	32
561:	ldx	[%g6 + TI_FLAGS], %l5
57	andcc	%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
58	be,pt	%icc, rtrap
59	 nop
60	call	syscall_trace_leave
61	 add	%sp, PTREGS_OFF, %o0
62	ba,pt	%xcc, rtrap
63	 nop
64
65	/* This is how fork() was meant to be done, 8 instruction entry.
66	 *
67	 * I questioned the following code briefly, let me clear things
68	 * up so you must not reason on it like I did.
69	 *
70	 * Know the fork_kpsr etc. we use in the sparc32 port?  We don't
71	 * need it here because the only piece of window state we copy to
72	 * the child is the CWP register.  Even if the parent sleeps,
73	 * we are safe because we stuck it into pt_regs of the parent
74	 * so it will not change.
75	 *
76	 * XXX This raises the question, whether we can do the same on
77	 * XXX sparc32 to get rid of fork_kpsr _and_ fork_kwim.  The
78	 * XXX answer is yes.  We stick fork_kpsr in UREG_G0 and
79	 * XXX fork_kwim in UREG_G1 (global registers are considered
80	 * XXX volatile across a system call in the sparc ABI I think
81	 * XXX if it isn't we can use regs->y instead, anyone who depends
82	 * XXX upon the Y register being preserved across a fork deserves
83	 * XXX to lose).
84	 *
85	 * In fact we should take advantage of that fact for other things
86	 * during system calls...
87	 */
88	.align	32
89sys_vfork: /* Under Linux, vfork and fork are just special cases of clone. */
90	sethi	%hi(0x4000 | 0x0100 | SIGCHLD), %o0
91	or	%o0, %lo(0x4000 | 0x0100 | SIGCHLD), %o0
92	ba,pt	%xcc, sys_clone
93sys_fork:
94	 clr	%o1
95	mov	SIGCHLD, %o0
96sys_clone:
97	flushw
98	movrz	%o1, %fp, %o1
99	mov	0, %o3
100	ba,pt	%xcc, sparc_do_fork
101	 add	%sp, PTREGS_OFF, %o2
102
103	.globl	ret_from_fork
104ret_from_fork:
105	/* Clear current_thread_info()->new_child. */
106	stb	%g0, [%g6 + TI_NEW_CHILD]
107	call	schedule_tail
108	 mov	%g7, %o0
109	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %o0
110	brnz,pt	%o0, ret_sys_call
111	 ldx	[%g6 + TI_FLAGS], %l0
112	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %l1
113	call	%l1
114	 ldx	[%sp + PTREGS_OFF + PT_V9_G2], %o0
115	ba,pt	%xcc, ret_sys_call
116	 mov	0, %o0
117
118	.globl	sparc_exit_group
119	.type	sparc_exit_group,#function
120sparc_exit_group:
121	sethi	%hi(sys_exit_group), %g7
122	ba,pt	%xcc, 1f
123	 or	%g7, %lo(sys_exit_group), %g7
124	.size	sparc_exit_group,.-sparc_exit_group
125
126	.globl	sparc_exit
127	.type	sparc_exit,#function
128sparc_exit:
129	sethi	%hi(sys_exit), %g7
130	or	%g7, %lo(sys_exit), %g7
1311:	rdpr	%pstate, %g2
132	wrpr	%g2, PSTATE_IE, %pstate
133	rdpr	%otherwin, %g1
134	rdpr	%cansave, %g3
135	add	%g3, %g1, %g3
136	wrpr	%g3, 0x0, %cansave
137	wrpr	%g0, 0x0, %otherwin
138	wrpr	%g2, 0x0, %pstate
139	jmpl	%g7, %g0
140	 stb	%g0, [%g6 + TI_WSAVED]
141	.size	sparc_exit,.-sparc_exit
142
143linux_sparc_ni_syscall:
144	sethi	%hi(sys_ni_syscall), %l7
145	ba,pt	%xcc, 4f
146	 or	%l7, %lo(sys_ni_syscall), %l7
147
148linux_syscall_trace32:
149	call	syscall_trace_enter
150	 add	%sp, PTREGS_OFF, %o0
151	brnz,pn	%o0, 3f
152	 mov	-ENOSYS, %o0
153
154	/* Syscall tracing can modify the registers.  */
155	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
156	sethi	%hi(sys_call_table32), %l7
157	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
158	or	%l7, %lo(sys_call_table32), %l7
159	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
160	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
161	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
162	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
163	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
164
165	cmp	%g1, NR_syscalls
166	bgeu,pn	%xcc, 3f
167	 mov	-ENOSYS, %o0
168
169	sll	%g1, 2, %l4
170	srl	%i0, 0, %o0
171	lduw	[%l7 + %l4], %l7
172	srl	%i4, 0, %o4
173	srl	%i1, 0, %o1
174	srl	%i2, 0, %o2
175	ba,pt	%xcc, 5f
176	 srl	%i3, 0, %o3
177
178linux_syscall_trace:
179	call	syscall_trace_enter
180	 add	%sp, PTREGS_OFF, %o0
181	brnz,pn	%o0, 3f
182	 mov	-ENOSYS, %o0
183
184	/* Syscall tracing can modify the registers.  */
185	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
186	sethi	%hi(sys_call_table64), %l7
187	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
188	or	%l7, %lo(sys_call_table64), %l7
189	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
190	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
191	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
192	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
193	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
194
195	cmp	%g1, NR_syscalls
196	bgeu,pn	%xcc, 3f
197	 mov	-ENOSYS, %o0
198
199	sll	%g1, 2, %l4
200	mov	%i0, %o0
201	lduw	[%l7 + %l4], %l7
202	mov	%i1, %o1
203	mov	%i2, %o2
204	mov	%i3, %o3
205	b,pt	%xcc, 2f
206	 mov	%i4, %o4
207
208
209	/* Linux 32-bit system calls enter here... */
210	.align	32
211	.globl	linux_sparc_syscall32
212linux_sparc_syscall32:
213	/* Direct access to user regs, much faster. */
214	cmp	%g1, NR_syscalls			! IEU1	Group
215	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
216	 srl	%i0, 0, %o0				! IEU0
217	sll	%g1, 2, %l4				! IEU0	Group
218	srl	%i4, 0, %o4				! IEU1
219	lduw	[%l7 + %l4], %l7			! Load
220	srl	%i1, 0, %o1				! IEU0	Group
221	ldx	[%g6 + TI_FLAGS], %l0		! Load
222
223	srl	%i3, 0, %o3				! IEU0
224	srl	%i2, 0, %o2				! IEU0	Group
225	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
226	bne,pn	%icc, linux_syscall_trace32		! CTI
227	 mov	%i0, %l5				! IEU1
2285:	call	%l7					! CTI	Group brk forced
229	 srl	%i5, 0, %o5				! IEU1
230	ba,pt	%xcc, 3f
231	 sra	%o0, 0, %o0
232
233	/* Linux native system calls enter here... */
234	.align	32
235	.globl	linux_sparc_syscall
236linux_sparc_syscall:
237	/* Direct access to user regs, much faster. */
238	cmp	%g1, NR_syscalls			! IEU1	Group
239	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
240	 mov	%i0, %o0				! IEU0
241	sll	%g1, 2, %l4				! IEU0	Group
242	mov	%i1, %o1				! IEU1
243	lduw	[%l7 + %l4], %l7			! Load
2444:	mov	%i2, %o2				! IEU0	Group
245	ldx	[%g6 + TI_FLAGS], %l0		! Load
246
247	mov	%i3, %o3				! IEU1
248	mov	%i4, %o4				! IEU0	Group
249	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
250	bne,pn	%icc, linux_syscall_trace		! CTI	Group
251	 mov	%i0, %l5				! IEU0
2522:	call	%l7					! CTI	Group brk forced
253	 mov	%i5, %o5				! IEU0
254	nop
255
2563:	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
257ret_sys_call:
258	ldx	[%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
259	mov	%ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
260	sllx	%g2, 32, %g2
261
262	cmp	%o0, -ERESTART_RESTARTBLOCK
263	bgeu,pn	%xcc, 1f
264	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
265	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
266
2672:
268	/* System call success, clear Carry condition code. */
269	andn	%g3, %g2, %g3
2703:
271	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
272	bne,pn	%icc, linux_syscall_trace2
273	 add	%l1, 0x4, %l2			! npc = npc+4
274	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
275	ba,pt	%xcc, rtrap
276	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
277
2781:
279	/* Check if force_successful_syscall_return()
280	 * was invoked.
281	 */
282	ldub	[%g6 + TI_SYS_NOERROR], %l2
283	brnz,pn %l2, 2b
284	 ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
285	/* System call failure, set Carry condition code.
286	 * Also, get abs(errno) to return to the process.
287	 */
288	sub	%g0, %o0, %o0
289	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
290	ba,pt	%xcc, 3b
291	 or	%g3, %g2, %g3
292
293linux_syscall_trace2:
294	call	syscall_trace_leave
295	 add	%sp, PTREGS_OFF, %o0
296	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
297	ba,pt	%xcc, rtrap
298	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
299