aya-ebpf: Take `c_void` instead of `bpf_map_def` in map helpers

`bpf_map_def` is a legacy map definition. To be able to introduce BTF
map definitions, make the `lookup` and `remove` helpers work with
`c_void` and let the callers cast the map types to it.

ebpf/aya-ebpf/src/lib.rs

@@ -28,11 +28,11 @@ pub mod helpers;
 pub mod maps;
 pub mod programs;
 
-use core::{ffi::c_void, ptr::NonNull};
+use core::ptr::NonNull;
 
 pub use aya_ebpf_cty as cty;
 pub use aya_ebpf_macros as macros;
-use cty::c_long;
+use cty::{c_long, c_void};
 use helpers::{
     bpf_get_current_comm, bpf_get_current_pid_tgid, bpf_get_current_uid_gid, bpf_map_delete_elem,
     bpf_map_lookup_elem, bpf_map_update_elem,
@@ -157,7 +157,7 @@ fn insert<K, V>(
 }
 
 #[inline]
-fn remove<K>(def: *mut bindings::bpf_map_def, key: &K) -> Result<(), c_long> {
+fn remove<K>(def: *mut c_void, key: &K) -> Result<(), c_long> {
     let key: *const _ = key;
     match unsafe { bpf_map_delete_elem(def.cast(), key.cast()) } {
         0 => Ok(()),
@@ -166,7 +166,7 @@ fn remove<K>(def: *mut bindings::bpf_map_def, key: &K) -> Result<(), c_long> {
 }
 
 #[inline]
-fn lookup<K, V>(def: *mut bindings::bpf_map_def, key: &K) -> Option<NonNull<V>> {
+fn lookup<K, V>(def: *mut c_void, key: &K) -> Option<NonNull<V>> {
     let key: *const _ = key;
     NonNull::new(unsafe { bpf_map_lookup_elem(def.cast(), key.cast()) }.cast())
 }

ebpf/aya-ebpf/src/maps/array.rs

@@ -65,7 +65,7 @@ impl<T> Array<T> {
 
     #[inline(always)]
     unsafe fn lookup(&self, index: u32) -> Option<NonNull<T>> {
-        lookup(self.def.get(), &index)
+        lookup(self.def.get().cast(), &index)
     }
 
     /// Sets the value of the element at the given index.

ebpf/aya-ebpf/src/maps/hash_map.rs

@@ -84,7 +84,7 @@ impl<K, V> HashMap<K, V> {
 
     #[inline]
     pub fn remove(&self, key: &K) -> Result<(), c_long> {
-        remove(self.def.get(), key)
+        remove(self.def.get().cast(), key)
     }
 }
 
@@ -160,7 +160,7 @@ impl<K, V> LruHashMap<K, V> {
 
     #[inline]
     pub fn remove(&self, key: &K) -> Result<(), c_long> {
-        remove(self.def.get(), key)
+        remove(self.def.get().cast(), key)
     }
 }
 
@@ -236,7 +236,7 @@ impl<K, V> PerCpuHashMap<K, V> {
 
     #[inline]
     pub fn remove(&self, key: &K) -> Result<(), c_long> {
-        remove(self.def.get(), key)
+        remove(self.def.get().cast(), key)
     }
 }
 
@@ -312,7 +312,7 @@ impl<K, V> LruPerCpuHashMap<K, V> {
 
     #[inline]
     pub fn remove(&self, key: &K) -> Result<(), c_long> {
-        remove(self.def.get(), key)
+        remove(self.def.get().cast(), key)
     }
 }
 
@@ -330,7 +330,7 @@ const fn build_def<K, V>(ty: u32, max_entries: u32, flags: u32, pin: PinningType
 
 #[inline]
 fn get_ptr_mut<K, V>(def: *mut bpf_map_def, key: &K) -> Option<*mut V> {
-    lookup(def, key).map(|p| p.as_ptr())
+    lookup(def.cast(), key).map(|p| p.as_ptr())
 }
 
 #[inline]

ebpf/aya-ebpf/src/maps/lpm_trie.rs

@@ -64,7 +64,7 @@ impl<K, V> LpmTrie<K, V> {
 
     #[inline]
     pub fn get(&self, key: &Key<K>) -> Option<&V> {
-        lookup(self.def.get(), key).map(|p| unsafe { p.as_ref() })
+        lookup(self.def.get().cast(), key).map(|p| unsafe { p.as_ref() })
     }
 
     #[inline]
@@ -74,7 +74,7 @@ impl<K, V> LpmTrie<K, V> {
 
     #[inline]
     pub fn remove(&self, key: &Key<K>) -> Result<(), c_long> {
-        remove(self.def.get(), key)
+        remove(self.def.get().cast(), key)
     }
 }
 

ebpf/aya-ebpf/src/maps/per_cpu_array.rs

@@ -65,6 +65,6 @@ impl<T> PerCpuArray<T> {
 
     #[inline(always)]
     unsafe fn lookup(&self, index: u32) -> Option<NonNull<T>> {
-        lookup(self.def.get(), &index)
+        lookup(self.def.get().cast(), &index)
     }
 }

ebpf/aya-ebpf/src/maps/sock_hash.rs

@@ -93,7 +93,7 @@ impl<K> SockHash<K> {
         key: impl Borrow<K>,
         flags: u64,
     ) -> Result<(), u32> {
-        let sk = lookup(self.def.get(), key.borrow()).ok_or(1u32)?;
+        let sk = lookup(self.def.get().cast(), key.borrow()).ok_or(1u32)?;
         let ret = unsafe { bpf_sk_assign(ctx.as_ptr().cast(), sk.as_ptr(), flags) };
         unsafe { bpf_sk_release(sk.as_ptr()) };
         match ret {

ebpf/aya-ebpf/src/maps/sock_map.rs

@@ -77,7 +77,7 @@ impl SockMap {
         index: u32,
         flags: u64,
     ) -> Result<(), u32> {
-        let sk = lookup(self.def.get(), &index).ok_or(1u32)?;
+        let sk = lookup(self.def.get().cast(), &index).ok_or(1u32)?;
         let ret = unsafe { bpf_sk_assign(ctx.as_ptr().cast(), sk.as_ptr(), flags) };
         unsafe { bpf_sk_release(sk.as_ptr()) };
         match ret {

ebpf/aya-ebpf/src/maps/xdp/dev_map.rs

@@ -105,7 +105,7 @@ impl DevMap {
     /// ```
     #[inline(always)]
     pub fn get(&self, index: u32) -> Option<DevMapValue> {
-        let value = lookup(self.def.get(), &index)?;
+        let value = lookup(self.def.get().cast(), &index)?;
         let value: &bpf_devmap_val = unsafe { value.as_ref() };
         Some(DevMapValue {
             if_index: value.ifindex,

ebpf/aya-ebpf/src/maps/xdp/dev_map_hash.rs

@@ -107,7 +107,7 @@ impl DevMapHash {
     /// ```
     #[inline(always)]
     pub fn get(&self, key: u32) -> Option<DevMapValue> {
-        let value = lookup(self.def.get(), &key)?;
+        let value = lookup(self.def.get().cast(), &key)?;
         let value: &bpf_devmap_val = unsafe { value.as_ref() };
         Some(DevMapValue {
             if_index: value.ifindex,

ebpf/aya-ebpf/src/maps/xdp/xsk_map.rs

@@ -124,7 +124,7 @@ impl XskMap {
     /// ```
     #[inline(always)]
     pub fn get(&self, index: u32) -> Option<u32> {
-        let value = lookup(self.def.get(), &index)?;
+        let value = lookup(self.def.get().cast(), &index)?;
         let value: &bpf_xdp_sock = unsafe { value.as_ref() };
         Some(value.queue_id)
     }