From e145242ea0df6b7d28fd7186e61d6840fa4bb06e Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Mon, 9 Apr 2018 12:51:42 +0200 Subject: syscalls/core, syscalls/x86: Clean up syscall stub naming convention Tidy the naming convention for compat syscall subs. Hints which describe the purpose of the stub go in front and receive a double underscore to denote that they are generated on-the-fly by the SYSCALL_DEFINEx() macro. For the generic case, this means (0xffffffff prefix removed): 810f08d0 t kernel_waitid # common C function (see kernel/exit.c) __do_sys_waitid # inlined helper doing the actual work # (takes original parameters as declared) 810f1aa0 T __se_sys_waitid # sign-extending C function calling inlined # helper (takes parameters of type long; # casts them to the declared type) 810f1aa0 T sys_waitid # alias to __se_sys_waitid() (taking # parameters as declared), to be included # in syscall table For x86, the naming is as follows: 810efc70 t kernel_waitid # common C function (see kernel/exit.c) __do_sys_waitid # inlined helper doing the actual work # (takes original parameters as declared) 810efd60 t __se_sys_waitid # sign-extending C function calling inlined # helper (takes parameters of type long; # casts them to the declared type) 810f1140 T __ia32_sys_waitid # IA32_EMULATION 32-bit-ptregs -> C stub, # calls __se_sys_waitid(); to be included # in syscall table 810f1110 T sys_waitid # x86 64-bit-ptregs -> C stub, calls # __se_sys_waitid(); to be included in # syscall table For x86, sys_waitid() will be re-named to __x64_sys_waitid in a follow-up patch. Suggested-by: Ingo Molnar Signed-off-by: Dominik Brodowski Cc: Al Viro Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20180409105145.5364-2-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar --- arch/x86/include/asm/syscall_wrapper.h | 35 +++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) (limited to 'arch/x86/include') diff --git a/arch/x86/include/asm/syscall_wrapper.h b/arch/x86/include/asm/syscall_wrapper.h index 49d7e49..798a3c2 100644 --- a/arch/x86/include/asm/syscall_wrapper.h +++ b/arch/x86/include/asm/syscall_wrapper.h @@ -22,7 +22,7 @@ #ifdef CONFIG_IA32_EMULATION /* * For IA32 emulation, we need to handle "compat" syscalls *and* create - * additional wrappers (aptly named __sys_ia32_sys_xyzzy) which decode the + * additional wrappers (aptly named __ia32_sys_xyzzy) which decode the * ia32 regs in the proper order for shared or "common" syscalls. As some * syscalls may not be implemented, we need to expand COND_SYSCALL in * kernel/sys_ni.c and SYS_NI in kernel/time/posix-stubs.c to cover this @@ -37,20 +37,20 @@ } \ #define SC_IA32_WRAPPERx(x, name, ...) \ - asmlinkage long __sys_ia32##name(const struct pt_regs *regs); \ - ALLOW_ERROR_INJECTION(__sys_ia32##name, ERRNO); \ - asmlinkage long __sys_ia32##name(const struct pt_regs *regs) \ + asmlinkage long __ia32_sys##name(const struct pt_regs *regs); \ + ALLOW_ERROR_INJECTION(__ia32_sys##name, ERRNO); \ + asmlinkage long __ia32_sys##name(const struct pt_regs *regs) \ { \ - return SyS##name(SC_IA32_REGS_TO_ARGS(x,__VA_ARGS__)); \ + return __se_sys##name(SC_IA32_REGS_TO_ARGS(x,__VA_ARGS__));\ } #define COND_SYSCALL(name) \ cond_syscall(sys_##name); \ - cond_syscall(__sys_ia32_##name) + cond_syscall(__ia32_sys_##name) #define SYS_NI(name) \ SYSCALL_ALIAS(sys_##name, sys_ni_posix_timers); \ - SYSCALL_ALIAS(__sys_ia32_##name, sys_ni_posix_timers) + SYSCALL_ALIAS(__ia32_sys_##name, sys_ni_posix_timers) #else /* CONFIG_IA32_EMULATION */ #define COMPAT_SC_IA32_STUBx(x, name, ...) @@ -115,9 +115,10 @@ * Instead of the generic __SYSCALL_DEFINEx() definition, this macro takes * struct pt_regs *regs as the only argument of the syscall stub named * sys_*(). It decodes just the registers it needs and passes them on to - * the SyS_*() wrapper and then to the SYSC_*() function doing the actual job. - * These wrappers and functions are inlined, meaning that the assembly looks - * as follows (slightly re-ordered): + * the __se_sys_*() wrapper performing sign extension and then to the + * __do_sys_*() function doing the actual job. These wrappers and functions + * are inlined (at least in very most cases), meaning that the assembly looks + * as follows (slightly re-ordered for better readability): * * : <-- syscall with 4 parameters * callq <__fentry__> @@ -140,7 +141,7 @@ * the call chain. * * If IA32_EMULATION is enabled, this macro generates an additional wrapper - * named __sys_ia32_*() which decodes the struct pt_regs *regs according + * named __ia32_sys_*() which decodes the struct pt_regs *regs according * to the i386 calling convention (bx, cx, dx, si, di, bp). * * As the generic SYSCALL_DEFINE0() macro does not decode any parameters for @@ -151,21 +152,21 @@ #define __SYSCALL_DEFINEx(x, name, ...) \ asmlinkage long sys##name(const struct pt_regs *regs); \ ALLOW_ERROR_INJECTION(sys##name, ERRNO); \ - static long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \ - static inline long SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__)); \ + static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \ + static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\ asmlinkage long sys##name(const struct pt_regs *regs) \ { \ - return SyS##name(SC_X86_64_REGS_TO_ARGS(x,__VA_ARGS__));\ + return __se_sys##name(SC_X86_64_REGS_TO_ARGS(x,__VA_ARGS__));\ } \ SC_IA32_WRAPPERx(x, name, __VA_ARGS__) \ - static long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \ + static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \ { \ - long ret = SYSC##name(__MAP(x,__SC_CAST,__VA_ARGS__)); \ + long ret = __do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\ __MAP(x,__SC_TEST,__VA_ARGS__); \ __PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \ return ret; \ } \ - static inline long SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__)) + static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) /* * For VSYSCALLS, we need to declare these three syscalls with the new -- cgit v1.1