xref: /openbmc/linux/arch/sparc/kernel/syscalls.S (revision efe84d40)
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:
90	flushw
91	ba,pt	%xcc, sparc_vfork
92	 add	%sp, PTREGS_OFF, %o0
93
94	.align	32
95sys_fork:
96	flushw
97	ba,pt	%xcc, sparc_fork
98	 add	%sp, PTREGS_OFF, %o0
99
100	.align	32
101sys_clone:
102	flushw
103	ba,pt	%xcc, sparc_clone
104	 add	%sp, PTREGS_OFF, %o0
105
106	.globl	ret_from_fork
107ret_from_fork:
108	/* Clear current_thread_info()->new_child. */
109	stb	%g0, [%g6 + TI_NEW_CHILD]
110	call	schedule_tail
111	 mov	%g7, %o0
112	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %o0
113	brnz,pt	%o0, ret_sys_call
114	 ldx	[%g6 + TI_FLAGS], %l0
115	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %l1
116	call	%l1
117	 ldx	[%sp + PTREGS_OFF + PT_V9_G2], %o0
118	ba,pt	%xcc, ret_sys_call
119	 mov	0, %o0
120
121	.globl	sparc_exit_group
122	.type	sparc_exit_group,#function
123sparc_exit_group:
124	sethi	%hi(sys_exit_group), %g7
125	ba,pt	%xcc, 1f
126	 or	%g7, %lo(sys_exit_group), %g7
127	.size	sparc_exit_group,.-sparc_exit_group
128
129	.globl	sparc_exit
130	.type	sparc_exit,#function
131sparc_exit:
132	sethi	%hi(sys_exit), %g7
133	or	%g7, %lo(sys_exit), %g7
1341:	rdpr	%pstate, %g2
135	wrpr	%g2, PSTATE_IE, %pstate
136	rdpr	%otherwin, %g1
137	rdpr	%cansave, %g3
138	add	%g3, %g1, %g3
139	wrpr	%g3, 0x0, %cansave
140	wrpr	%g0, 0x0, %otherwin
141	wrpr	%g2, 0x0, %pstate
142	jmpl	%g7, %g0
143	 stb	%g0, [%g6 + TI_WSAVED]
144	.size	sparc_exit,.-sparc_exit
145
146linux_sparc_ni_syscall:
147	sethi	%hi(sys_ni_syscall), %l7
148	ba,pt	%xcc, 4f
149	 or	%l7, %lo(sys_ni_syscall), %l7
150
151linux_syscall_trace32:
152	call	syscall_trace_enter
153	 add	%sp, PTREGS_OFF, %o0
154	brnz,pn	%o0, 3f
155	 mov	-ENOSYS, %o0
156
157	/* Syscall tracing can modify the registers.  */
158	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
159	sethi	%hi(sys_call_table32), %l7
160	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
161	or	%l7, %lo(sys_call_table32), %l7
162	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
163	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
164	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
165	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
166	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
167
168	cmp	%g1, NR_syscalls
169	bgeu,pn	%xcc, 3f
170	 mov	-ENOSYS, %o0
171
172	sll	%g1, 2, %l4
173	srl	%i0, 0, %o0
174	lduw	[%l7 + %l4], %l7
175	srl	%i4, 0, %o4
176	srl	%i1, 0, %o1
177	srl	%i2, 0, %o2
178	ba,pt	%xcc, 5f
179	 srl	%i3, 0, %o3
180
181linux_syscall_trace:
182	call	syscall_trace_enter
183	 add	%sp, PTREGS_OFF, %o0
184	brnz,pn	%o0, 3f
185	 mov	-ENOSYS, %o0
186
187	/* Syscall tracing can modify the registers.  */
188	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
189	sethi	%hi(sys_call_table64), %l7
190	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
191	or	%l7, %lo(sys_call_table64), %l7
192	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
193	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
194	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
195	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
196	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
197
198	cmp	%g1, NR_syscalls
199	bgeu,pn	%xcc, 3f
200	 mov	-ENOSYS, %o0
201
202	sll	%g1, 2, %l4
203	mov	%i0, %o0
204	lduw	[%l7 + %l4], %l7
205	mov	%i1, %o1
206	mov	%i2, %o2
207	mov	%i3, %o3
208	b,pt	%xcc, 2f
209	 mov	%i4, %o4
210
211
212	/* Linux 32-bit system calls enter here... */
213	.align	32
214	.globl	linux_sparc_syscall32
215linux_sparc_syscall32:
216	/* Direct access to user regs, much faster. */
217	cmp	%g1, NR_syscalls			! IEU1	Group
218	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
219	 srl	%i0, 0, %o0				! IEU0
220	sll	%g1, 2, %l4				! IEU0	Group
221	srl	%i4, 0, %o4				! IEU1
222	lduw	[%l7 + %l4], %l7			! Load
223	srl	%i1, 0, %o1				! IEU0	Group
224	ldx	[%g6 + TI_FLAGS], %l0		! Load
225
226	srl	%i3, 0, %o3				! IEU0
227	srl	%i2, 0, %o2				! IEU0	Group
228	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
229	bne,pn	%icc, linux_syscall_trace32		! CTI
230	 mov	%i0, %l5				! IEU1
2315:	call	%l7					! CTI	Group brk forced
232	 srl	%i5, 0, %o5				! IEU1
233	ba,pt	%xcc, 3f
234	 sra	%o0, 0, %o0
235
236	/* Linux native system calls enter here... */
237	.align	32
238	.globl	linux_sparc_syscall
239linux_sparc_syscall:
240	/* Direct access to user regs, much faster. */
241	cmp	%g1, NR_syscalls			! IEU1	Group
242	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
243	 mov	%i0, %o0				! IEU0
244	sll	%g1, 2, %l4				! IEU0	Group
245	mov	%i1, %o1				! IEU1
246	lduw	[%l7 + %l4], %l7			! Load
2474:	mov	%i2, %o2				! IEU0	Group
248	ldx	[%g6 + TI_FLAGS], %l0		! Load
249
250	mov	%i3, %o3				! IEU1
251	mov	%i4, %o4				! IEU0	Group
252	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
253	bne,pn	%icc, linux_syscall_trace		! CTI	Group
254	 mov	%i0, %l5				! IEU0
2552:	call	%l7					! CTI	Group brk forced
256	 mov	%i5, %o5				! IEU0
257	nop
258
2593:	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
260ret_sys_call:
261	ldx	[%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
262	mov	%ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
263	sllx	%g2, 32, %g2
264
265	cmp	%o0, -ERESTART_RESTARTBLOCK
266	bgeu,pn	%xcc, 1f
267	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
268	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
269
2702:
271	/* System call success, clear Carry condition code. */
272	andn	%g3, %g2, %g3
2733:
274	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
275	bne,pn	%icc, linux_syscall_trace2
276	 add	%l1, 0x4, %l2			! npc = npc+4
277	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
278	ba,pt	%xcc, rtrap
279	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
280
2811:
282	/* Check if force_successful_syscall_return()
283	 * was invoked.
284	 */
285	ldub	[%g6 + TI_SYS_NOERROR], %l2
286	brnz,pn %l2, 2b
287	 ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
288	/* System call failure, set Carry condition code.
289	 * Also, get abs(errno) to return to the process.
290	 */
291	sub	%g0, %o0, %o0
292	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
293	ba,pt	%xcc, 3b
294	 or	%g3, %g2, %g3
295
296linux_syscall_trace2:
297	call	syscall_trace_leave
298	 add	%sp, PTREGS_OFF, %o0
299	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
300	ba,pt	%xcc, rtrap
301	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
302