On Mon, 2022-05-09 at 20:04 -0700, Alexei Starovoitov wrote:
> On Mon, May 02, 2022 at 11:09:38PM +0000, Delyan Kratunov wrote:
> > In order to add a version of bpf_prog_run_array which accesses the
> > bpf_prog->aux member, we need bpf_prog to be more than a forward
> > declaration inside bpf.h.
> >
> > Given that filter.h already includes bpf.h, this merely reorders
> > the type declarations for filter.h users. bpf.h users now have access to
> > bpf_prog internals.
> >
> > Signed-off-by: Delyan Kratunov <delyank@xxxxxx>
> > ---
> > include/linux/bpf.h | 36 ++++++++++++++++++++++++++++++++++++
> > include/linux/filter.h | 34 ----------------------------------
> > 2 files changed, 36 insertions(+), 34 deletions(-)
> >
> > diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> > index be94833d390a..57ec619cf729 100644
> > --- a/include/linux/bpf.h
> > +++ b/include/linux/bpf.h
> > @@ -5,6 +5,7 @@
> > #define _LINUX_BPF_H 1
> >
> > #include <uapi/linux/bpf.h>
> > +#include <uapi/linux/filter.h>
>
> because of struct sock_filter ?
> Pls fwd declare it instead.
Yes but you can't forward declare it in this context.
It's used as within DECLARE_FLEX_ARRAY, so a forward declaration leads to:
./include/linux/bpf.h:1107:56: error: array type has incomplete element type ‘struct
sock_filter’
1107 | DECLARE_FLEX_ARRAY(struct sock_filter, insns);
>
> > #include <linux/workqueue.h>
> > #include <linux/file.h>
> > @@ -22,6 +23,7 @@
> > #include <linux/sched/mm.h>
> > #include <linux/slab.h>
> > #include <linux/percpu-refcount.h>
> > +#include <linux/stddef.h>
> > #include <linux/bpfptr.h>
> > #include <linux/btf.h>
> >
> > @@ -1068,6 +1070,40 @@ struct bpf_prog_aux {
> > };
> > };
> >
> > +struct bpf_prog {
> > + u16 pages; /* Number of allocated pages */
> > + u16 jited:1, /* Is our filter JIT'ed? */
> > + jit_requested:1,/* archs need to JIT the prog */
> > + gpl_compatible:1, /* Is filter GPL compatible? */
> > + cb_access:1, /* Is control block accessed? */
> > + dst_needed:1, /* Do we need dst entry? */
> > + blinding_requested:1, /* needs constant blinding */
> > + blinded:1, /* Was blinded */
> > + is_func:1, /* program is a bpf function */
> > + kprobe_override:1, /* Do we override a kprobe? */
> > + has_callchain_buf:1, /* callchain buffer allocated? */
> > + enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */
> > + call_get_stack:1, /* Do we call bpf_get_stack() or bpf_get_stackid() */
> > + call_get_func_ip:1, /* Do we call get_func_ip() */
> > + tstamp_type_access:1; /* Accessed __sk_buff->tstamp_type */
> > + enum bpf_prog_type type; /* Type of BPF program */
> > + enum bpf_attach_type expected_attach_type; /* For some prog types */
> > + u32 len; /* Number of filter blocks */
> > + u32 jited_len; /* Size of jited insns in bytes */
> > + u8 tag[BPF_TAG_SIZE];
> > + struct bpf_prog_stats __percpu *stats;
> > + int __percpu *active;
> > + unsigned int (*bpf_func)(const void *ctx,
> > + const struct bpf_insn *insn);
> > + struct bpf_prog_aux *aux; /* Auxiliary fields */
> > + struct sock_fprog_kern *orig_prog; /* Original BPF program */
> > + /* Instructions for interpreter */
> > + union {
> > + DECLARE_FLEX_ARRAY(struct sock_filter, insns);
> > + DECLARE_FLEX_ARRAY(struct bpf_insn, insnsi);
> > + };
> > +};
> > +
> > struct bpf_array_aux {
> > /* Programs with direct jumps into programs part of this array. */
> > struct list_head poke_progs;
> > diff --git a/include/linux/filter.h b/include/linux/filter.h
> > index ed0c0ff42ad5..d0cbb31b1b4d 100644
> > --- a/include/linux/filter.h
> > +++ b/include/linux/filter.h
> > @@ -559,40 +559,6 @@ struct bpf_prog_stats {
> > struct u64_stats_sync syncp;
> > } __aligned(2 * sizeof(u64));
> >
> > -struct bpf_prog {
> > - u16 pages; /* Number of allocated pages */
> > - u16 jited:1, /* Is our filter JIT'ed? */
> > - jit_requested:1,/* archs need to JIT the prog */
> > - gpl_compatible:1, /* Is filter GPL compatible? */
> > - cb_access:1, /* Is control block accessed? */
> > - dst_needed:1, /* Do we need dst entry? */
> > - blinding_requested:1, /* needs constant blinding */
> > - blinded:1, /* Was blinded */
> > - is_func:1, /* program is a bpf function */
> > - kprobe_override:1, /* Do we override a kprobe? */
> > - has_callchain_buf:1, /* callchain buffer allocated? */
> > - enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */
> > - call_get_stack:1, /* Do we call bpf_get_stack() or bpf_get_stackid() */
> > - call_get_func_ip:1, /* Do we call get_func_ip() */
> > - tstamp_type_access:1; /* Accessed __sk_buff->tstamp_type */
> > - enum bpf_prog_type type; /* Type of BPF program */
> > - enum bpf_attach_type expected_attach_type; /* For some prog types */
> > - u32 len; /* Number of filter blocks */
> > - u32 jited_len; /* Size of jited insns in bytes */
> > - u8 tag[BPF_TAG_SIZE];
> > - struct bpf_prog_stats __percpu *stats;
> > - int __percpu *active;
> > - unsigned int (*bpf_func)(const void *ctx,
> > - const struct bpf_insn *insn);
> > - struct bpf_prog_aux *aux; /* Auxiliary fields */
> > - struct sock_fprog_kern *orig_prog; /* Original BPF program */
> > - /* Instructions for interpreter */
> > - union {
> > - DECLARE_FLEX_ARRAY(struct sock_filter, insns);
> > - DECLARE_FLEX_ARRAY(struct bpf_insn, insnsi);
> > - };
> > -};
> > -
> > struct sk_filter {
> > refcount_t refcnt;
> > struct rcu_head rcu;
> > --
> > 2.35.1
