diff options
| author | Martin KaFai Lau <martin.lau@kernel.org> | 2023-03-07 22:59:24 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-03-10 11:05:28 -0800 |
| commit | fc6652aab6ad545de70b772550da9043d0b47f1c (patch) | |
| tree | efcb165b250a068e3de214b80d70fbea64dab58d /include/linux/bpf_local_storage.h | |
| parent | 121f31f3e00dfc1acbca43f6f35779e050b56cfc (diff) | |
bpf: Remember smap in bpf_local_storage
This patch remembers which smap triggers the allocation
of a 'struct bpf_local_storage' object. The local_storage is
allocated during the very first selem added to the owner.
The smap pointer is needed when using the bpf_mem_cache_free
in a later patch because it needs to free to the correct
smap's bpf_mem_alloc object.
When a selem is being removed, it needs to check if it is
the selem that triggers the creation of the local_storage.
If it is, the local_storage->smap pointer will be reset to NULL.
This NULL reset is done under the local_storage->lock in
bpf_selem_unlink_storage_nolock() when a selem is being removed.
Also note that the local_storage may not go away even
local_storage->smap is NULL because there may be other
selem still stored in the local_storage.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20230308065936.1550103-6-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include/linux/bpf_local_storage.h')
| -rw-r--r-- | include/linux/bpf_local_storage.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/bpf_local_storage.h b/include/linux/bpf_local_storage.h index 5908a954ddc2..613b1805ed9f 100644 --- a/include/linux/bpf_local_storage.h +++ b/include/linux/bpf_local_storage.h @@ -83,6 +83,7 @@ struct bpf_local_storage_elem { struct bpf_local_storage { struct bpf_local_storage_data __rcu *cache[BPF_LOCAL_STORAGE_CACHE_SIZE]; + struct bpf_local_storage_map __rcu *smap; struct hlist_head list; /* List of bpf_local_storage_elem */ void *owner; /* The object that owns the above "list" of * bpf_local_storage_elem. |