Commit 92258b5b authored by Abhishek Dubey's avatar Abhishek Dubey Committed by Madhavan Srinivasan
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powerpc32/bpf: Add fsession support 



Extend JIT support of fsession in powerpc64 trampoline, since
ppc64 and ppc32 shares common trampoline implementation.
Arch specific helpers handle 64-bit data copy using 32 bit regs.

Need to validate fsession support along with trampoline support.

Signed-off-by: default avatarAbhishek Dubey <adubey@linux.ibm.com>
Acked-by: default avatarHari Bathini <hbathini@linux.ibm.com>
Signed-off-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260401141043.41513-2-adubey@linux.ibm.com
parent 6fab063b

arch/powerpc/net/bpf_jit_comp.c

+7 −1
Original line number Diff line number Diff line
@@ -542,7 +542,13 @@ bool bpf_jit_supports_private_stack(void) 


bool bpf_jit_supports_fsession(void)

{

	return IS_ENABLED(CONFIG_PPC64);

	/*

	 * TODO: Remove after validating support

	 * for fsession and trampoline on ppc32.

	 */

	if (IS_ENABLED(CONFIG_PPC32))

		return -EOPNOTSUPP;

	return true;

}



bool bpf_jit_supports_arena(void)

arch/powerpc/net/bpf_jit_comp32.c

+35 −0
Original line number Diff line number Diff line
@@ -123,6 +123,41 @@ void bpf_jit_realloc_regs(struct codegen_context *ctx) 
	}

}



void prepare_for_fsession_fentry(u32 *image, struct codegen_context *ctx, int cookie_cnt,

						int cookie_off, int retval_off)

{

	/*

	 * Set session cookies value

	 * Clear cookies field on stack

	 * Ensure retval to be cleared on fentry

	 */

	EMIT(PPC_RAW_LI(bpf_to_ppc(TMP_REG), 0));



	for (int i = 0; i < cookie_cnt; i++) {

		EMIT(PPC_RAW_STW(bpf_to_ppc(TMP_REG), _R1, cookie_off + 4 * i));

		EMIT(PPC_RAW_STW(bpf_to_ppc(TMP_REG), _R1, cookie_off + 4 * i + 4));

	}



	EMIT(PPC_RAW_STW(bpf_to_ppc(TMP_REG), _R1, retval_off));

	EMIT(PPC_RAW_STW(bpf_to_ppc(TMP_REG), _R1, retval_off + 4));

}



void store_func_meta(u32 *image, struct codegen_context *ctx,

					u64 func_meta, int func_meta_off)

{

	/*

	 * Store func_meta to stack: [R1 + func_meta_off] = func_meta

	 * func_meta := argument count in first byte + cookie value

	 */

	/* Store lower word */

	EMIT(PPC_RAW_LI32(bpf_to_ppc(TMP_REG), (u32)func_meta));

	EMIT(PPC_RAW_STW(bpf_to_ppc(TMP_REG), _R1, func_meta_off));



	/* Store upper word */

	EMIT(PPC_RAW_LI32(bpf_to_ppc(TMP_REG), (u32)(func_meta >> 32)));

	EMIT(PPC_RAW_STW(bpf_to_ppc(TMP_REG), _R1, func_meta_off + 4));

}



void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx)

{

	int i;