xref: /openbmc/linux/arch/sparc/kernel/syscalls.S (revision f7777dcc)
1	/* SunOS's execv() call only specifies the argv argument, the
2	 * environment settings are the same as the calling processes.
3	 */
4sys64_execve:
5	set	sys_execve, %g1
6	jmpl	%g1, %g0
7	 flushw
8
9#ifdef CONFIG_COMPAT
10sunos_execv:
11	mov	%g0, %o2
12sys32_execve:
13	set	compat_sys_execve, %g1
14	jmpl	%g1, %g0
15	 flushw
16#endif
17
18	.align	32
19sys_sparc_pipe:
20	ba,pt	%xcc, sys_sparc_pipe_real
21	 add	%sp, PTREGS_OFF, %o0
22sys_nis_syscall:
23	ba,pt	%xcc, c_sys_nis_syscall
24	 add	%sp, PTREGS_OFF, %o0
25sys_memory_ordering:
26	ba,pt	%xcc, sparc_memory_ordering
27	 add	%sp, PTREGS_OFF, %o1
28#ifdef CONFIG_COMPAT
29sys32_sigstack:
30	ba,pt	%xcc, do_sys32_sigstack
31	 mov	%i6, %o2
32#endif
33	.align	32
34#ifdef CONFIG_COMPAT
35sys32_sigreturn:
36	add	%sp, PTREGS_OFF, %o0
37	call	do_sigreturn32
38	 add	%o7, 1f-.-4, %o7
39	nop
40#endif
41sys_rt_sigreturn:
42	add	%sp, PTREGS_OFF, %o0
43	call	do_rt_sigreturn
44	 add	%o7, 1f-.-4, %o7
45	nop
46#ifdef CONFIG_COMPAT
47sys32_rt_sigreturn:
48	add	%sp, PTREGS_OFF, %o0
49	call	do_rt_sigreturn32
50	 add	%o7, 1f-.-4, %o7
51	nop
52#endif
53	.align	32
541:	ldx	[%g6 + TI_FLAGS], %l5
55	andcc	%l5, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
56	be,pt	%icc, rtrap
57	 nop
58	call	syscall_trace_leave
59	 add	%sp, PTREGS_OFF, %o0
60	ba,pt	%xcc, rtrap
61	 nop
62
63	/* This is how fork() was meant to be done, 8 instruction entry.
64	 *
65	 * I questioned the following code briefly, let me clear things
66	 * up so you must not reason on it like I did.
67	 *
68	 * Know the fork_kpsr etc. we use in the sparc32 port?  We don't
69	 * need it here because the only piece of window state we copy to
70	 * the child is the CWP register.  Even if the parent sleeps,
71	 * we are safe because we stuck it into pt_regs of the parent
72	 * so it will not change.
73	 *
74	 * XXX This raises the question, whether we can do the same on
75	 * XXX sparc32 to get rid of fork_kpsr _and_ fork_kwim.  The
76	 * XXX answer is yes.  We stick fork_kpsr in UREG_G0 and
77	 * XXX fork_kwim in UREG_G1 (global registers are considered
78	 * XXX volatile across a system call in the sparc ABI I think
79	 * XXX if it isn't we can use regs->y instead, anyone who depends
80	 * XXX upon the Y register being preserved across a fork deserves
81	 * XXX to lose).
82	 *
83	 * In fact we should take advantage of that fact for other things
84	 * during system calls...
85	 */
86	.align	32
87sys_vfork: /* Under Linux, vfork and fork are just special cases of clone. */
88	sethi	%hi(0x4000 | 0x0100 | SIGCHLD), %o0
89	or	%o0, %lo(0x4000 | 0x0100 | SIGCHLD), %o0
90	ba,pt	%xcc, sys_clone
91sys_fork:
92	 clr	%o1
93	mov	SIGCHLD, %o0
94sys_clone:
95	flushw
96	movrz	%o1, %fp, %o1
97	mov	0, %o3
98	ba,pt	%xcc, sparc_do_fork
99	 add	%sp, PTREGS_OFF, %o2
100
101	.globl	ret_from_fork
102ret_from_fork:
103	/* Clear current_thread_info()->new_child. */
104	stb	%g0, [%g6 + TI_NEW_CHILD]
105	call	schedule_tail
106	 mov	%g7, %o0
107	ldx	[%sp + PTREGS_OFF + PT_V9_I0], %o0
108	brnz,pt	%o0, ret_sys_call
109	 ldx	[%g6 + TI_FLAGS], %l0
110	ldx	[%sp + PTREGS_OFF + PT_V9_G1], %l1
111	call	%l1
112	 ldx	[%sp + PTREGS_OFF + PT_V9_G2], %o0
113	ba,pt	%xcc, ret_sys_call
114	 mov	0, %o0
115
116	.globl	sparc_exit_group
117	.type	sparc_exit_group,#function
118sparc_exit_group:
119	sethi	%hi(sys_exit_group), %g7
120	ba,pt	%xcc, 1f
121	 or	%g7, %lo(sys_exit_group), %g7
122	.size	sparc_exit_group,.-sparc_exit_group
123
124	.globl	sparc_exit
125	.type	sparc_exit,#function
126sparc_exit:
127	sethi	%hi(sys_exit), %g7
128	or	%g7, %lo(sys_exit), %g7
1291:	rdpr	%pstate, %g2
130	wrpr	%g2, PSTATE_IE, %pstate
131	rdpr	%otherwin, %g1
132	rdpr	%cansave, %g3
133	add	%g3, %g1, %g3
134	wrpr	%g3, 0x0, %cansave
135	wrpr	%g0, 0x0, %otherwin
136	wrpr	%g2, 0x0, %pstate
137	jmpl	%g7, %g0
138	 stb	%g0, [%g6 + TI_WSAVED]
139	.size	sparc_exit,.-sparc_exit
140
141linux_sparc_ni_syscall:
142	sethi	%hi(sys_ni_syscall), %l7
143	ba,pt	%xcc, 4f
144	 or	%l7, %lo(sys_ni_syscall), %l7
145
146linux_syscall_trace32:
147	call	syscall_trace_enter
148	 add	%sp, PTREGS_OFF, %o0
149	brnz,pn	%o0, 3f
150	 mov	-ENOSYS, %o0
151	srl	%i0, 0, %o0
152	srl	%i4, 0, %o4
153	srl	%i1, 0, %o1
154	srl	%i2, 0, %o2
155	ba,pt	%xcc, 5f
156	 srl	%i3, 0, %o3
157
158linux_syscall_trace:
159	call	syscall_trace_enter
160	 add	%sp, PTREGS_OFF, %o0
161	brnz,pn	%o0, 3f
162	 mov	-ENOSYS, %o0
163	mov	%i0, %o0
164	mov	%i1, %o1
165	mov	%i2, %o2
166	mov	%i3, %o3
167	b,pt	%xcc, 2f
168	 mov	%i4, %o4
169
170
171	/* Linux 32-bit system calls enter here... */
172	.align	32
173	.globl	linux_sparc_syscall32
174linux_sparc_syscall32:
175	/* Direct access to user regs, much faster. */
176	cmp	%g1, NR_syscalls			! IEU1	Group
177	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
178	 srl	%i0, 0, %o0				! IEU0
179	sll	%g1, 2, %l4				! IEU0	Group
180	srl	%i4, 0, %o4				! IEU1
181	lduw	[%l7 + %l4], %l7			! Load
182	srl	%i1, 0, %o1				! IEU0	Group
183	ldx	[%g6 + TI_FLAGS], %l0		! Load
184
185	srl	%i3, 0, %o3				! IEU0
186	srl	%i2, 0, %o2				! IEU0	Group
187	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
188	bne,pn	%icc, linux_syscall_trace32		! CTI
189	 mov	%i0, %l5				! IEU1
1905:	call	%l7					! CTI	Group brk forced
191	 srl	%i5, 0, %o5				! IEU1
192	ba,a,pt	%xcc, 3f
193
194	/* Linux native system calls enter here... */
195	.align	32
196	.globl	linux_sparc_syscall
197linux_sparc_syscall:
198	/* Direct access to user regs, much faster. */
199	cmp	%g1, NR_syscalls			! IEU1	Group
200	bgeu,pn	%xcc, linux_sparc_ni_syscall		! CTI
201	 mov	%i0, %o0				! IEU0
202	sll	%g1, 2, %l4				! IEU0	Group
203	mov	%i1, %o1				! IEU1
204	lduw	[%l7 + %l4], %l7			! Load
2054:	mov	%i2, %o2				! IEU0	Group
206	ldx	[%g6 + TI_FLAGS], %l0		! Load
207
208	mov	%i3, %o3				! IEU1
209	mov	%i4, %o4				! IEU0	Group
210	andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
211	bne,pn	%icc, linux_syscall_trace		! CTI	Group
212	 mov	%i0, %l5				! IEU0
2132:	call	%l7					! CTI	Group brk forced
214	 mov	%i5, %o5				! IEU0
215	nop
216
2173:	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
218ret_sys_call:
219	ldx	[%sp + PTREGS_OFF + PT_V9_TSTATE], %g3
220	sra	%o0, 0, %o0
221	mov	%ulo(TSTATE_XCARRY | TSTATE_ICARRY), %g2
222	sllx	%g2, 32, %g2
223
224	cmp	%o0, -ERESTART_RESTARTBLOCK
225	bgeu,pn	%xcc, 1f
226	 andcc	%l0, (_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT|_TIF_SYSCALL_TRACEPOINT), %g0
227	ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
228
2292:
230	/* System call success, clear Carry condition code. */
231	andn	%g3, %g2, %g3
2323:
233	stx	%g3, [%sp + PTREGS_OFF + PT_V9_TSTATE]
234	bne,pn	%icc, linux_syscall_trace2
235	 add	%l1, 0x4, %l2			! npc = npc+4
236	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
237	ba,pt	%xcc, rtrap
238	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
239
2401:
241	/* Check if force_successful_syscall_return()
242	 * was invoked.
243	 */
244	ldub	[%g6 + TI_SYS_NOERROR], %l2
245	brnz,pn %l2, 2b
246	 ldx	[%sp + PTREGS_OFF + PT_V9_TNPC], %l1 ! pc = npc
247	/* System call failure, set Carry condition code.
248	 * Also, get abs(errno) to return to the process.
249	 */
250	sub	%g0, %o0, %o0
251	stx	%o0, [%sp + PTREGS_OFF + PT_V9_I0]
252	ba,pt	%xcc, 3b
253	 or	%g3, %g2, %g3
254
255linux_syscall_trace2:
256	call	syscall_trace_leave
257	 add	%sp, PTREGS_OFF, %o0
258	stx	%l1, [%sp + PTREGS_OFF + PT_V9_TPC]
259	ba,pt	%xcc, rtrap
260	 stx	%l2, [%sp + PTREGS_OFF + PT_V9_TNPC]
261