cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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syscalls.S (7674B)


      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]