[RFC PATCH net-next 4/6] PPC: net: bpf_jit_comp: refactor the BPF JIT interface

Xi Wang
2013-04-26T07:51:44Z

Implement the refactored bpf_jit_compile() and bpf_jit_free().

Signed-off-by: Xi Wang <xi.wang@gmail.com>
---
arch/powerpc/net/bpf_jit_comp.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index c427ae3..a82e400 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -31,11 +31,11 @@ static inline void bpf_flush_icache(void *start, void *end)
flush_icache_range((unsigned long)start, (unsigned long)end);
}

-static void bpf_jit_build_prologue(struct sk_filter *fp, u32 *image,
+static void bpf_jit_build_prologue(struct sock_filter *filter,
+ u32 *image,
struct codegen_context *ctx)
{
int i;
- const struct sock_filter *filter = fp->insns;

if (ctx->seen & (SEEN_MEM | SEEN_DATAREF)) {
/* Make stackframe */
@@ -135,12 +135,12 @@ static void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx)
((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset)

/* Assemble the body code between the prologue & epilogue. */
-static int bpf_jit_build_body(struct sk_filter *fp, u32 *image,
+static int bpf_jit_build_body(struct sock_filter *filter,
+ unsigned int flen,
+ u32 *image,
struct codegen_context *ctx,
unsigned int *addrs)
{
- const struct sock_filter *filter = fp->insns;
- int flen = fp->len;
u8 *func;
unsigned int true_cond;
int i;
@@ -564,7 +564,7 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image,
return 0;
}

-void bpf_jit_compile(struct sk_filter *fp)
+bpf_func_t bpf_jit_compile(struct sock_filter *filter, unsigned int flen)
{
unsigned int proglen;
unsigned int alloclen;
@@ -573,14 +573,14 @@ void bpf_jit_compile(struct sk_filter *fp)
unsigned int *addrs;
struct codegen_context cgctx;
int pass;
- int flen = fp->len;
+ bpf_func_t bpf_func = sk_run_filter;

if (!bpf_jit_enable)
- return;
+ return bpf_func;

addrs = kzalloc((flen+1) * sizeof(*addrs), GFP_KERNEL);
if (addrs == NULL)
- return;
+ return bpf_func;

/*
* There are multiple assembly passes as the generated code will change
@@ -636,7 +636,7 @@ void bpf_jit_compile(struct sk_filter *fp)
cgctx.seen = 0;
cgctx.pc_ret0 = -1;
/* Scouting faux-generate pass 0 */
- if (bpf_jit_build_body(fp, 0, &cgctx, addrs))
+ if (bpf_jit_build_body(filter, flen, 0, &cgctx, addrs))
/* We hit something illegal or unsupported. */
goto out;

@@ -645,7 +645,7 @@ void bpf_jit_compile(struct sk_filter *fp)
* update ctgtx.idx as it pretends to output instructions, then we can
* calculate total size from idx.
*/
- bpf_jit_build_prologue(fp, 0, &cgctx);
+ bpf_jit_build_prologue(filter, 0, &cgctx);
bpf_jit_build_epilogue(0, &cgctx);

proglen = cgctx.idx * 4;
@@ -661,8 +661,8 @@ void bpf_jit_compile(struct sk_filter *fp)
for (pass = 1; pass < 3; pass++) {
/* Now build the prologue, body code & epilogue for real. */
cgctx.idx = 0;
- bpf_jit_build_prologue(fp, code_base, &cgctx);
- bpf_jit_build_body(fp, code_base, &cgctx, addrs);
+ bpf_jit_build_prologue(filter, code_base, &cgctx);
+ bpf_jit_build_body(filter, flen, code_base, &cgctx, addrs);
bpf_jit_build_epilogue(code_base, &cgctx);

if (bpf_jit_enable > 1)
@@ -681,11 +681,11 @@ void bpf_jit_compile(struct sk_filter *fp)
/* Function descriptor nastiness: Address + TOC */
((u64 *)image)[0] = (u64)code_base;
((u64 *)image)[1] = local_paca->kernel_toc;
- fp->bpf_func = (void *)image;
+ bpf_func = (void *)image;
}
out:
kfree(addrs);
- return;
+ return bpf_func;
}

static void jit_free_defer(struct work_struct *arg)
@@ -696,10 +696,10 @@ static void jit_free_defer(struct work_struct *arg)
/* run from softirq, we must use a work_struct to call
* module_free() from process context
*/
-void bpf_jit_free(struct sk_filter *fp)
+void bpf_jit_free(bpf_func_t bpf_func)
{
- if (fp->bpf_func != sk_run_filter) {
- struct work_struct *work = (struct work_struct *)fp->bpf_func;
+ if (bpf_func != sk_run_filter) {
+ struct work_struct *work = (struct work_struct *)bpf_func;

INIT_WORK(work, jit_free_defer);
schedule_work(work);
--
1.8.1.2