armbian/linux-cix
0
0
Fork 0
mirror of https://github.com/armbian/linux-cix.git synced 2026-01-06 12:30:45 -08:00
Code Issues Packages Projects Releases Wiki Activity

syscalls/core, syscalls/x86: Clean up syscall stub naming convention

Browse Source 
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)

 <inline>     __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)

 <inline>     __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 <mingo@kernel.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180409105145.5364-2-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Dominik Brodowski
2018-04-09 12:51:42 +02:00
committed by Ingo Molnar
parent 6dc936f175
commit e145242ea0
4 changed files with 242 additions and 236 deletions
Download Patch File Download Diff File Expand all files Collapse all files

424
arch/x86/entry/syscalls/syscall_32.tbl
View File

File diff suppressed because it is too large Load Diff

35
arch/x86/include/asm/syscall_wrapper.h
View File

@@ -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):
*
* <sys_recv>: <-- 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

17
include/linux/syscalls.h
View File

@@ -223,21 +223,26 @@ static inline int is_syscall_trace_event(struct trace_event_call *tp_event)
#define __PROTECT(...) asmlinkage_protect(__VA_ARGS__)
/*
* The asmlinkage stub is aliased to a function named __se_sys_*() which
* sign-extends 32-bit ints to longs whenever needed. The actual work is
* done within __do_sys_*().
*/
#ifndef __SYSCALL_DEFINEx
#define __SYSCALL_DEFINEx(x, name, ...) \
asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(SyS##name)))); \
__attribute__((alias(__stringify(__se_sys##name)))); \
ALLOW_ERROR_INJECTION(sys##name, ERRNO); \
static inline long SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__)); \
asmlinkage long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
asmlinkage long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
asmlinkage 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__))
#endif /* __SYSCALL_DEFINEx */
/*

2
scripts/bloat-o-meter
View File

@@ -30,7 +30,7 @@ def getsizes(file, format):
if type in format:
# strip generated symbols
if name.startswith("__mod_"): continue
if name.startswith("SyS_"): continue
if name.startswith("__se_sys"): continue
if name.startswith("compat_SyS_"): continue
if name == "linux_banner": continue
# statics and some other optimizations adds random .NUMBER