diff options
Diffstat (limited to 'linux-user/host/riscv/safe-syscall.inc.S')
| -rw-r--r-- | linux-user/host/riscv/safe-syscall.inc.S | 114 |
1 files changed, 57 insertions, 57 deletions
diff --git a/linux-user/host/riscv/safe-syscall.inc.S b/linux-user/host/riscv/safe-syscall.inc.S index 9ca3fbf..95c4832 100644 --- a/linux-user/host/riscv/safe-syscall.inc.S +++ b/linux-user/host/riscv/safe-syscall.inc.S @@ -10,68 +10,68 @@ * See the COPYING file in the top-level directory. */ - .global safe_syscall_base - .global safe_syscall_start - .global safe_syscall_end - .type safe_syscall_base, @function - .type safe_syscall_start, @function - .type safe_syscall_end, @function + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end + .type safe_syscall_base, @function + .type safe_syscall_start, @function + .type safe_syscall_end, @function - /* - * This is the entry point for making a system call. The calling - * convention here is that of a C varargs function with the - * first argument an 'int *' to the signal_pending flag, the - * second one the system call number (as a 'long'), and all further - * arguments being syscall arguments (also 'long'). - * We return a long which is the syscall's return value, which - * may be negative-errno on failure. Conversion to the - * -1-and-errno-set convention is done by the calling wrapper. - */ + /* + * This is the entry point for making a system call. The calling + * convention here is that of a C varargs function with the + * first argument an 'int *' to the signal_pending flag, the + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + * We return a long which is the syscall's return value, which + * may be negative-errno on failure. Conversion to the + * -1-and-errno-set convention is done by the calling wrapper. + */ safe_syscall_base: - .cfi_startproc - /* - * The syscall calling convention is nearly the same as C: - * we enter with a0 == *signal_pending - * a1 == syscall number - * a2 ... a7 == syscall arguments - * and return the result in a0 - * and the syscall instruction needs - * a7 == syscall number - * a0 ... a5 == syscall arguments - * and returns the result in a0 - * Shuffle everything around appropriately. - */ - mv t0, a0 /* signal_pending pointer */ - mv t1, a1 /* syscall number */ - mv a0, a2 /* syscall arguments */ - mv a1, a3 - mv a2, a4 - mv a3, a5 - mv a4, a6 - mv a5, a7 - mv a7, t1 + .cfi_startproc + /* + * The syscall calling convention is nearly the same as C: + * we enter with a0 == *signal_pending + * a1 == syscall number + * a2 ... a7 == syscall arguments + * and return the result in a0 + * and the syscall instruction needs + * a7 == syscall number + * a0 ... a5 == syscall arguments + * and returns the result in a0 + * Shuffle everything around appropriately. + */ + mv t0, a0 /* signal_pending pointer */ + mv t1, a1 /* syscall number */ + mv a0, a2 /* syscall arguments */ + mv a1, a3 + mv a2, a4 + mv a3, a5 + mv a4, a6 + mv a5, a7 + mv a7, t1 - /* - * This next sequence of code works in conjunction with the - * rewind_if_safe_syscall_function(). If a signal is taken - * and the interrupted PC is anywhere between 'safe_syscall_start' - * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. - * The code sequence must therefore be able to cope with this, and - * the syscall instruction must be the final one in the sequence. - */ + /* + * This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken + * and the interrupted PC is anywhere between 'safe_syscall_start' + * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. + * The code sequence must therefore be able to cope with this, and + * the syscall instruction must be the final one in the sequence. + */ safe_syscall_start: - /* If signal_pending is non-zero, don't do the call */ - lw t1, 0(t0) - bnez t1, 0f - scall + /* If signal_pending is non-zero, don't do the call */ + lw t1, 0(t0) + bnez t1, 0f + scall safe_syscall_end: - /* code path for having successfully executed the syscall */ - ret + /* code path for having successfully executed the syscall */ + ret 0: - /* code path when we didn't execute the syscall */ - li a0, -TARGET_ERESTARTSYS - ret - .cfi_endproc + /* code path when we didn't execute the syscall */ + li a0, -TARGET_ERESTARTSYS + ret + .cfi_endproc - .size safe_syscall_base, .-safe_syscall_base + .size safe_syscall_base, .-safe_syscall_base |