xref: /linux/arch/sparc/kernel/syscalls.S (revision 37a93dd5c49b5fda807fd204edf2547c3493319c)
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	.align	32
107__sys_clone3:
108	flushw
109	ba,pt	%xcc, sparc_clone3
110	 add	%sp, PTREGS_OFF, %o0
111
112	.globl	ret_from_fork
113ret_from_fork:
114	/* Clear current_thread_info()->new_child. */
115	stb	%g0, [%g6 + TI_NEW_CHILD]
116	call	schedule_tail
117	 mov	%g7, %o0
118	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %o0
119	brnz,pt	%o0, ret_sys_call
120	 ldx	[%g6 + TI_FLAGS], %l0
121	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %l1
122	brz,pt	%l1, ret_sys_call
123	 nop
124	call	%l1
125	 ldx	[%sp + PTREGS_OFF + PT_V9_G2], %o0
126	ba,pt	%xcc, ret_sys_call
127	 mov	0, %o0
128
129	.globl	sparc_exit_group
130	.type	sparc_exit_group,#function
131sparc_exit_group:
132	sethi	%hi(sys_exit_group), %g7
133	ba,pt	%xcc, 1f
134	 or	%g7, %lo(sys_exit_group), %g7
135	.size	sparc_exit_group,.-sparc_exit_group
136
137	.globl	sparc_exit
138	.type	sparc_exit,#function
139sparc_exit:
140	sethi	%hi(sys_exit), %g7
141	or	%g7, %lo(sys_exit), %g7
1421:	rdpr	%pstate, %g2
143	wrpr	%g2, PSTATE_IE, %pstate
144	rdpr	%otherwin, %g1
145	rdpr	%cansave, %g3
146	add	%g3, %g1, %g3
147	wrpr	%g3, 0x0, %cansave
148	wrpr	%g0, 0x0, %otherwin
149	wrpr	%g2, 0x0, %pstate
150	jmpl	%g7, %g0
151	 stb	%g0, [%g6 + TI_WSAVED]
152	.size	sparc_exit,.-sparc_exit
153
154linux_sparc_ni_syscall:
155	sethi	%hi(sys_ni_syscall), %l7
156	ba,pt	%xcc, 4f
157	 or	%l7, %lo(sys_ni_syscall), %l7
158
159linux_syscall_trace32:
160	call	syscall_trace_enter
161	 add	%sp, PTREGS_OFF, %o0
162	brnz,pn	%o0, 3f
163	 mov	-ENOSYS, %o0
164
165	/* Syscall tracing can modify the registers.  */
166	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
167	sethi	%hi(sys_call_table32), %l7
168	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
169	or	%l7, %lo(sys_call_table32), %l7
170	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
171	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
172	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
173	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
174	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
175
176	cmp	%g1, NR_syscalls
177	bgeu,pn	%xcc, 3f
178	 mov	-ENOSYS, %o0
179
180	sll	%g1, 2, %l4
181	srl	%i0, 0, %o0
182	lduw	[%l7 + %l4], %l7
183	srl	%i4, 0, %o4
184	srl	%i1, 0, %o1
185	srl	%i2, 0, %o2
186	ba,pt	%xcc, 5f
187	 srl	%i3, 0, %o3
188
189linux_syscall_trace:
190	call	syscall_trace_enter
191	 add	%sp, PTREGS_OFF, %o0
192	brnz,pn	%o0, 3f
193	 mov	-ENOSYS, %o0
194
195	/* Syscall tracing can modify the registers.  */
196	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %g1
197	sethi	%hi(sys_call_table64), %l7
198	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %i0
199	or	%l7, %lo(sys_call_table64), %l7
200	ldx	[%sp + PTREGS_OFF + PT_V9_I1], %i1
201	ldx	[%sp + PTREGS_OFF + PT_V9_I2], %i2
202	ldx	[%sp + PTREGS_OFF + PT_V9_I3], %i3
203	ldx	[%sp + PTREGS_OFF + PT_V9_I4], %i4
204	ldx	[%sp + PTREGS_OFF + PT_V9_I5], %i5
205
206	cmp	%g1, NR_syscalls
207	bgeu,pn	%xcc, 3f
208	 mov	-ENOSYS, %o0
209
210	sll	%g1, 2, %l4
211	mov	%i0, %o0
212	lduw	[%l7 + %l4], %l7
213	mov	%i1, %o1
214	mov	%i2, %o2
215	mov	%i3, %o3
216	b,pt	%xcc, 2f
217	 mov	%i4, %o4
218
219
220	/* Linux 32-bit system calls enter here... */
221	.align	32
222	.globl	linux_sparc_syscall32
223linux_sparc_syscall32:
224	/* Direct access to user regs, much faster. */
225	cmp	%g1, NR_syscalls			! IEU1	Group
226	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
227	 srl	%i0, 0, %o0				! IEU0
228	sll	%g1, 2, %l4				! IEU0	Group
229	srl	%i4, 0, %o4				! IEU1
230	lduw	[%l7 + %l4], %l7			! Load
231	srl	%i1, 0, %o1				! IEU0	Group
232	ldx	[%g6 + TI_FLAGS], %l0		! Load
233
234	srl	%i3, 0, %o3				! IEU0
235	srl	%i2, 0, %o2				! IEU0	Group
236	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
237	bne,pn	%icc, linux_syscall_trace32		! CTI
238	 mov	%i0, %l5				! IEU1
2395:	call	%l7					! CTI	Group brk forced
240	 srl	%i5, 0, %o5				! IEU1
241	ba,pt	%xcc, 3f
242	 sra	%o0, 0, %o0
243
244	/* Linux native system calls enter here... */
245	.align	32
246	.globl	linux_sparc_syscall
247linux_sparc_syscall:
248	/* Direct access to user regs, much faster. */
249	cmp	%g1, NR_syscalls			! IEU1	Group
250	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
251	 mov	%i0, %o0				! IEU0
252	sll	%g1, 2, %l4				! IEU0	Group
253	mov	%i1, %o1				! IEU1
254	lduw	[%l7 + %l4], %l7			! Load
2554:	mov	%i2, %o2				! IEU0	Group
256	ldx	[%g6 + TI_FLAGS], %l0		! Load
257
258	mov	%i3, %o3				! IEU1
259	mov	%i4, %o4				! IEU0	Group
260	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
261	bne,pn	%icc, linux_syscall_trace		! CTI	Group
262	 mov	%i0, %l5				! IEU0
2632:	call	%l7					! CTI	Group brk forced
264	 mov	%i5, %o5				! IEU0
265	nop
266
2673:	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
268ret_sys_call:
269	ldx	[%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
270	mov	%ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
271	sllx	%g2, 32, %g2
272
273	cmp	%o0, -ERESTART_RESTARTBLOCK
274	bgeu,pn	%xcc, 1f
275	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT|_TIF_NOHZ), %g0
276	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
277
2782:
279	/* System call success, clear Carry condition code. */
280	andn	%g3, %g2, %g3
2813:
282	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
283	bne,pn	%icc, linux_syscall_trace2
284	 add	%l1, 0x4, %l2			! npc = npc+4
285	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
286	ba,pt	%xcc, rtrap
287	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
288
2891:
290	/* Check if force_successful_syscall_return()
291	 * was invoked.
292	 */
293	ldub	[%g6 + TI_SYS_NOERROR], %l2
294	brnz,pn %l2, 2b
295	 ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
296	/* System call failure, set Carry condition code.
297	 * Also, get abs(errno) to return to the process.
298	 */
299	sub	%g0, %o0, %o0
300	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
301	ba,pt	%xcc, 3b
302	 or	%g3, %g2, %g3
303
304linux_syscall_trace2:
305	call	syscall_trace_leave
306	 add	%sp, PTREGS_OFF, %o0
307	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
308	ba,pt	%xcc, rtrap
309	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
310