# readahead __________________________________________________ # # asmlinkage ssize_t # ssize_t sys32_readahead(int fd, unsigned off_lo, unsigned off_hi, size_t count) # COMPAT_SYSCALL_DEFINE4(x86_readahead, int, fd, unsigned int, off_lo, # unsigned int, off_hi, size_t, count) # @define _SYSCALL_COMPAT_READAHEAD_NAME %( name = "readahead" %) @define _SYSCALL_COMPAT_READAHEAD_ARGSTR %( argstr = sprintf("%d, %d, %u", fd, offset, count) %) @define _SYSCALL_COMPAT_READAHEAD_REGARGS %( fd = int_arg(1) offset = ((uint_arg(3) << 32) | uint_arg(2)) count = ulong_arg(4) %) probe syscall.compat_readahead = dw_syscall.compat_readahead !, nd_syscall.compat_readahead ? {} probe syscall.compat_readahead.return = dw_syscall.compat_readahead.return !, nd_syscall.compat_readahead.return ? {} # dw_compat_readahead _____________________________________________________ probe dw_syscall.compat_readahead = kernel.function("sys32_readahead") ? { @_SYSCALL_COMPAT_READAHEAD_NAME fd = __int32($fd) offset = (($off_hi << 32) | $off_lo) count = __uint32($count) @_SYSCALL_COMPAT_READAHEAD_ARGSTR } probe dw_syscall.compat_readahead.return = kernel.function("sys32_readahead").return ? { @_SYSCALL_COMPAT_READAHEAD_NAME @SYSC_RETVALSTR($return) } # nd_compat_readahead _____________________________________________________ probe nd_syscall.compat_readahead = nd1_syscall.compat_readahead!, nd2_syscall.compat_readahead!, tp_syscall.compat_readahead { } probe nd1_syscall.compat_readahead = kprobe.function("sys32_readahead") ?, kprobe.function("compat_sys_x86_readahead") ? { @_SYSCALL_COMPAT_READAHEAD_NAME asmlinkage() @_SYSCALL_COMPAT_READAHEAD_REGARGS @_SYSCALL_COMPAT_READAHEAD_ARGSTR } /* kernel 4.17+ */ probe nd2_syscall.compat_readahead = kprobe.function(@arch_syscall_prefix "compat_sys_x86_readahead") ? { __set_syscall_pt_regs(pointer_arg(1)) @_SYSCALL_COMPAT_READAHEAD_NAME @_SYSCALL_COMPAT_READAHEAD_REGARGS @_SYSCALL_COMPAT_READAHEAD_ARGSTR } /* kernel 3.5+, but undesirable because it affects all syscalls */ probe tp_syscall.compat_readahead = kernel.trace("sys_enter") { __set_syscall_pt_regs($regs) @__compat_syscall_gate(@const("__NR_ia32_readahead")) @_SYSCALL_COMPAT_READAHEAD_NAME @_SYSCALL_COMPAT_READAHEAD_REGARGS @_SYSCALL_COMPAT_READAHEAD_ARGSTR } probe nd_syscall.compat_readahead.return = nd1_syscall.compat_readahead.return!, nd2_syscall.compat_readahead.return!, tp_syscall.compat_readahead.return { } probe nd1_syscall.compat_readahead.return = kprobe.function("sys32_readahead").return ?, kprobe.function("compat_sys_x86_readahead").return ? { @_SYSCALL_COMPAT_READAHEAD_NAME @SYSC_RETVALSTR(returnval()) } /* kernel 4.17+ */ probe nd2_syscall.compat_readahead.return = kprobe.function(@arch_syscall_prefix "compat_sys_x86_readahead").return ? { @_SYSCALL_COMPAT_READAHEAD_NAME @SYSC_RETVALSTR(returnval()) } /* kernel 3.5+, but undesirable because it affects all syscalls */ probe tp_syscall.compat_readahead.return = kernel.trace("sys_exit") { __set_syscall_pt_regs($regs) @__compat_syscall_gate(@const("__NR_ia32_readahead")) @_SYSCALL_COMPAT_READAHEAD_NAME @SYSC_RETVALSTR($ret) }