[0/7] LoongArch: Switch to relative extable and other improvements

Message

Youling Tang Oct. 10, 2022, 9:32 a.m. UTC

Similar as other architectures such as arm64, x86 and so on, use
offsets relative to the exception table entry values rather than
absolute addresses for both the exception locationand the fixup.
And recently, arm64 and x86 remove anonymous out-of-line fixups, we
want to acchieve the same result.

Implementing the relative extable will facilitate subsequent kernel
relocation support, which can reduce relocation operations to the
extable (thanks to Jinyang for the suggestion).

At the same time, add BPF exception tables handling.


Youling Tang (7):
  LoongArch: Consolidate __ex_table construction
  LoongArch: Switch to relative exception tables
  LoongArch: extable: Add `type` and `data` fields
  LoongArch: Add gpr-num.h
  LoongArch: extable: Add a dedicated uaccess handler
  LoongArch: vmlinux.lds.S: Remove `.fixup` section
  LoongArch: bpf: Add BPF exception tables

 arch/loongarch/include/asm/asm-extable.h | 65 ++++++++++++++++++
 arch/loongarch/include/asm/extable.h     | 49 ++++++++++++++
 arch/loongarch/include/asm/futex.h       | 27 ++------
 arch/loongarch/include/asm/gpr-num.h     | 22 +++++++
 arch/loongarch/include/asm/uaccess.h     | 24 ++-----
 arch/loongarch/kernel/fpu.S              |  5 +-
 arch/loongarch/kernel/vmlinux.lds.S      |  4 +-
 arch/loongarch/lib/clear_user.S          | 17 ++---
 arch/loongarch/lib/copy_user.S           | 19 ++----
 arch/loongarch/mm/extable.c              | 60 ++++++++++++++---
 arch/loongarch/net/bpf_jit.c             | 84 ++++++++++++++++++++++--
 arch/loongarch/net/bpf_jit.h             |  2 +
 scripts/mod/modpost.c                    | 13 ++++
 scripts/sorttable.c                      |  2 +-
 14 files changed, 312 insertions(+), 81 deletions(-)
 create mode 100644 arch/loongarch/include/asm/asm-extable.h
 create mode 100644 arch/loongarch/include/asm/extable.h
 create mode 100644 arch/loongarch/include/asm/gpr-num.h