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powerpc/bpf: implement bpf_arch_text_copy

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bpf_arch_text_copy is used to dump JITed binary to RX page, allowing
multiple BPF programs to share the same page. Use the newly introduced
patch_instructions() to implement it.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231020141358.643575-3-hbathini@linux.ibm.com
This commit is contained in:
Hari Bathini 2023-10-20 19:43:55 +05:30 committed by Michael Ellerman
parent 465cabc97b
commit 6efc1675ac
1 changed files with 19 additions and 1 deletions
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20
arch/powerpc/net/bpf_jit_comp.c
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@ -13,9 +13,13 @@
#include <linux/netdevice.h>
#include <linux/filter.h>
#include <linux/if_vlan.h>
#include <asm/kprobes.h>
#include <linux/kernel.h>
#include <linux/memory.h>
#include <linux/bpf.h>
#include <asm/kprobes.h>
#include <asm/code-patching.h>
#include "bpf_jit.h"
static void bpf_jit_fill_ill_insns(void *area, unsigned int size)
@ -274,3 +278,17 @@ int bpf_add_extable_entry(struct bpf_prog *fp, u32 *image, int pass, struct code
ctx->exentry_idx++;
return 0;
}
void *bpf_arch_text_copy(void *dst, void *src, size_t len)
{
int err;
if (WARN_ON_ONCE(core_kernel_text((unsigned long)dst)))
return ERR_PTR(-EINVAL);
mutex_lock(&text_mutex);
err = patch_instructions(dst, src, len, false);
mutex_unlock(&text_mutex);
return err ? ERR_PTR(err) : dst;
}