microblaze: Support ptrace syscall tracing.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
index c7353e7..acc1f05 100644
--- a/arch/microblaze/kernel/entry.S
+++ b/arch/microblaze/kernel/entry.S
@@ -308,38 +308,69 @@
swi r12, r1, PTO+PT_R0;
tovirt(r1,r1)
- la r15, r0, ret_from_trap-8
/* where the trap should return need -8 to adjust for rtsd r15, 8*/
/* Jump to the appropriate function for the system call number in r12
* (r12 is not preserved), or return an error if r12 is not valid. The LP
* register should point to the location where
* the called function should return. [note that MAKE_SYS_CALL uses label 1] */
- /* See if the system call number is valid. */
+
+ # Step into virtual mode.
+ set_vms;
+ addik r11, r0, 3f
+ rtid r11, 0
+ nop
+3:
+ add r11, r0, CURRENT_TASK /* Get current task ptr into r11 */
+ lwi r11, r11, TS_THREAD_INFO /* get thread info */
+ lwi r11, r11, TI_FLAGS /* get flags in thread info */
+ andi r11, r11, _TIF_WORK_SYSCALL_MASK
+ beqi r11, 4f
+
+ addik r3, r0, -ENOSYS
+ swi r3, r1, PTO + PT_R3
+ brlid r15, do_syscall_trace_enter
+ addik r5, r1, PTO + PT_R0
+
+ # do_syscall_trace_enter returns the new syscall nr.
+ addk r12, r0, r3
+ lwi r5, r1, PTO+PT_R5;
+ lwi r6, r1, PTO+PT_R6;
+ lwi r7, r1, PTO+PT_R7;
+ lwi r8, r1, PTO+PT_R8;
+ lwi r9, r1, PTO+PT_R9;
+ lwi r10, r1, PTO+PT_R10;
+4:
+/* Jump to the appropriate function for the system call number in r12
+ * (r12 is not preserved), or return an error if r12 is not valid.
+ * The LP register should point to the location where the called function
+ * should return. [note that MAKE_SYS_CALL uses label 1] */
+ /* See if the system call number is valid */
addi r11, r12, -__NR_syscalls;
- bgei r11,1f;
+ bgei r11,5f;
/* Figure out which function to use for this system call. */
/* Note Microblaze barrel shift is optional, so don't rely on it */
add r12, r12, r12; /* convert num -> ptr */
add r12, r12, r12;
/* Trac syscalls and stored them to r0_ram */
- lwi r3, r12, 0x400 + TOPHYS(r0_ram)
+ lwi r3, r12, 0x400 + r0_ram
addi r3, r3, 1
- swi r3, r12, 0x400 + TOPHYS(r0_ram)
+ swi r3, r12, 0x400 + r0_ram
- lwi r12, r12, TOPHYS(sys_call_table); /* Function ptr */
- /* Make the system call. to r12*/
- set_vms;
- rtid r12, 0;
- nop;
+ # Find and jump into the syscall handler.
+ lwi r12, r12, sys_call_table
+ /* where the trap should return need -8 to adjust for rtsd r15, 8 */
+ la r15, r0, ret_from_trap-8
+ bra r12
+
/* The syscall number is invalid, return an error. */
-1: VM_ON; /* RETURN() expects virtual mode*/
+5:
addi r3, r0, -ENOSYS;
rtsd r15,8; /* looks like a normal subroutine return */
or r0, r0, r0
-/* Entry point used to return from a syscall/trap. */
+/* Entry point used to return from a syscall/trap */
/* We re-enable BIP bit before state restore */
C_ENTRY(ret_from_trap):
set_bip; /* Ints masked for state restore*/
@@ -349,6 +380,23 @@
/* We're returning to user mode, so check for various conditions that
* trigger rescheduling. */
+ # FIXME: Restructure all these flag checks.
+ add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */
+ lwi r11, r11, TS_THREAD_INFO; /* get thread info */
+ lwi r11, r11, TI_FLAGS; /* get flags in thread info */
+ andi r11, r11, _TIF_WORK_SYSCALL_MASK
+ beqi r11, 1f
+
+ swi r3, r1, PTO + PT_R3
+ swi r4, r1, PTO + PT_R4
+ brlid r15, do_syscall_trace_leave
+ addik r5, r1, PTO + PT_R0
+ lwi r3, r1, PTO + PT_R3
+ lwi r4, r1, PTO + PT_R4
+1:
+
+ /* We're returning to user mode, so check for various conditions that
+ * trigger rescheduling. */
/* Get current task ptr into r11 */
add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */
lwi r11, r11, TS_THREAD_INFO; /* get thread info */