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Chenghao Duan
1702e2d22c
This commit adds support for BPF dynamic code modification on the LoongArch architecture: 1. Add bpf_arch_text_copy() for instruction block copying. 2. Add bpf_arch_text_poke() for runtime instruction patching. 3. Add bpf_arch_text_invalidate() for code invalidation. On LoongArch, since symbol addresses in the direct mapping region can't be reached via relative jump instructions from the paged mapping region, we use the move_imm+jirl instruction pair as absolute jump instructions. These require 2-5 instructions, so we reserve 5 NOP instructions in the program as placeholders for function jumps. The larch_insn_text_copy() function is solely used for BPF. And the use of larch_insn_text_copy() requires PAGE_SIZE alignment. Currently, only the size of the BPF trampoline is page-aligned. Co-developed-by: George Guo <guodongtai@kylinos.cn> Signed-off-by: George Guo <guodongtai@kylinos.cn> Signed-off-by: Chenghao Duan <duanchenghao@kylinos.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: maoxiaochuan <maoxiaochuan@loongson.cn>