From b4a5d26d8835d972995f0a0a2f805a8845bafa0b Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Thu, 2 Nov 2017 11:04:18 -0200 Subject: linux: Consolidate sigaction implementation This patch consolidates all Linux sigaction implementations on the default sysdeps/unix/sysv/linux/sigaction.c. The idea is remove redundant code and simplify new ports addition by following the current generic Linux User API (UAPI). The UAPI for new ports defines a generic extensible sigaction struct as: struct sigaction { __sighandler_t sa_handler; unsigned long sa_flags; #ifdef SA_RESTORER void (*sa_restorer) (void); #endif sigset_t sa_mask; }; Where SA_RESTORER is just placed for compatibility reasons (news ports should not add it). A similar definition is used on generic kernel_sigaction.h. The user exported sigaction definition is not changed, so for most architectures it requires an adjustment to kernel expected one for the syscall. The main changes are: - All architectures now define and use a kernel_sigaction struct meant for the syscall, even for the architectures where the user sigaction has the same layout of the kernel expected one (s390-64 and ia64). Although it requires more work for these architectures, it simplifies the generic implementation. Also, sigaction is hardly a hotspot where micro optimization would play an important role. - The generic kernel_sigaction definition is now aligned with expected UAPI one for newer ports, where SA_RESTORER and sa_restorer are not expected to be defined. This means adding kernel_sigaction for current architectures that does define it (m68k, nios2, powerpc, s390, sh, sparc, and tile) and which rely on previous generic definition. - Remove old MIPS usage of sa_restorer. This was removed since 2.6.27 (2957c9e61ee9c - "[MIPS] IRIX: Goodbye and thanks for all the fish"). - The remaining arch-specific sigaction.c are to handle ABI idiosyncrasies (like SPARC kernel ABI for rt_sigaction that requires an additional stub argument). So for new ports the generic implementation should work if its uses Linux UAPI. If SA_RESTORER is still required (due some architecture limitation), it should define its own kernel_sigaction.h, define it and include generic header (assuming it still uses the default generic kernel layout). Checked on x86_64-linux-gnu, i686-linux-gnu, arm-linux-gnueabihf, aarch64-linux-gnu, sparc64-linux-gnu, sparcv9-linux-gnu, powerpc-linux-gnu, powerpc64-linux-gnu, ia64-linux-gnu and alpha-linux-gnu. I also checked the build on all remaining affected ABIs. * sysdeps/unix/sysv/linux/aarch64/sigaction.c: Use default Linux version as base implementation. * sysdeps/unix/sysv/linux/arm/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/i386/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/x86_64/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/alpha/kernel_sigaction.h: Add include guards, remove unrequired definitions and update comments. * sysdeps/unix/sysv/linux/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/mips/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/ia64/kernel_sigaction.h: New file. * sysdeps/unix/sysv/linux/m68k/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/nios2/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/powerpc/kernel_sigaction: Likewise. * sysdeps/unix/sysv/linux/s390/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/sh/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/sparc/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/tile/kernel_sigaction.h: Likewise. * sysdeps/unix/sysv/linux/ia64/sigaction.c: Remove file. * sysdeps/unix/sysv/linux/mips/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/sigaction.c: Likewise. * sysdeps/unix/sysv/linux/sigaction.c: Add STUB, SET_SA_RESTORER, and RESET_SA_RESTORER hooks. --- sysdeps/unix/sysv/linux/sh/kernel_sigaction.h | 8 ++++++++ 1 file changed, 8 insertions(+) create mode 100644 sysdeps/unix/sysv/linux/sh/kernel_sigaction.h (limited to 'sysdeps/unix/sysv/linux/sh/kernel_sigaction.h') diff --git a/sysdeps/unix/sysv/linux/sh/kernel_sigaction.h b/sysdeps/unix/sysv/linux/sh/kernel_sigaction.h new file mode 100644 index 0000000000..7ebcd08d62 --- /dev/null +++ b/sysdeps/unix/sysv/linux/sh/kernel_sigaction.h @@ -0,0 +1,8 @@ +/* SH uses the generic Linux UAPI but defines SA_RESTORER. */ +#define SA_RESTORER 0x04000000 +#include + +#define SET_SA_RESTORER(kact, act) \ + (kact)->sa_restorer = (act)->sa_restorer +#define RESET_SA_RESTORER(act, kact) \ + (act)->sa_restorer = (kact)->sa_restorer -- cgit 1.4.1