From c83597fa5dc6b322e9bdf929e5f4136a3f4aa4db Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 25 Oct 2022 21:28:45 -0700 Subject: bpf: Refactor some inode/task/sk storage functions for reuse Refactor codes so that inode/task/sk storage implementation can maximally share the same code. I also added some comments in new function bpf_local_storage_unlink_nolock() to make codes easy to understand. There is no functionality change. Acked-by: David Vernet Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20221026042845.672944-1-yhs@fb.com Signed-off-by: Alexei Starovoitov --- kernel/bpf/bpf_inode_storage.c | 38 +++----------------------------------- 1 file changed, 3 insertions(+), 35 deletions(-) (limited to 'kernel/bpf/bpf_inode_storage.c') diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c index 5f7683b19199..6a1d4d22816a 100644 --- a/kernel/bpf/bpf_inode_storage.c +++ b/kernel/bpf/bpf_inode_storage.c @@ -56,11 +56,9 @@ static struct bpf_local_storage_data *inode_storage_lookup(struct inode *inode, void bpf_inode_storage_free(struct inode *inode) { - struct bpf_local_storage_elem *selem; struct bpf_local_storage *local_storage; bool free_inode_storage = false; struct bpf_storage_blob *bsb; - struct hlist_node *n; bsb = bpf_inode(inode); if (!bsb) @@ -74,30 +72,11 @@ void bpf_inode_storage_free(struct inode *inode) return; } - /* Neither the bpf_prog nor the bpf-map's syscall - * could be modifying the local_storage->list now. - * Thus, no elem can be added-to or deleted-from the - * local_storage->list by the bpf_prog or by the bpf-map's syscall. - * - * It is racing with bpf_local_storage_map_free() alone - * when unlinking elem from the local_storage->list and - * the map's bucket->list. - */ raw_spin_lock_bh(&local_storage->lock); - hlist_for_each_entry_safe(selem, n, &local_storage->list, snode) { - /* Always unlink from map before unlinking from - * local_storage. - */ - bpf_selem_unlink_map(selem); - free_inode_storage = bpf_selem_unlink_storage_nolock( - local_storage, selem, false, false); - } + free_inode_storage = bpf_local_storage_unlink_nolock(local_storage); raw_spin_unlock_bh(&local_storage->lock); rcu_read_unlock(); - /* free_inoode_storage should always be true as long as - * local_storage->list was non-empty. - */ if (free_inode_storage) kfree_rcu(local_storage, rcu); } @@ -226,23 +205,12 @@ static int notsupp_get_next_key(struct bpf_map *map, void *key, static struct bpf_map *inode_storage_map_alloc(union bpf_attr *attr) { - struct bpf_local_storage_map *smap; - - smap = bpf_local_storage_map_alloc(attr); - if (IS_ERR(smap)) - return ERR_CAST(smap); - - smap->cache_idx = bpf_local_storage_cache_idx_get(&inode_cache); - return &smap->map; + return bpf_local_storage_map_alloc(attr, &inode_cache); } static void inode_storage_map_free(struct bpf_map *map) { - struct bpf_local_storage_map *smap; - - smap = (struct bpf_local_storage_map *)map; - bpf_local_storage_cache_idx_free(&inode_cache, smap->cache_idx); - bpf_local_storage_map_free(smap, NULL); + bpf_local_storage_map_free(map, &inode_cache, NULL); } BTF_ID_LIST_SINGLE(inode_storage_map_btf_ids, struct, -- cgit v1.2.3 From 3144bfa5078e0df7507a4de72061501e6a0e56be Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 29 Nov 2022 21:21:47 -0800 Subject: bpf: Fix a compilation failure with clang lto build When building the kernel with clang lto (CONFIG_LTO_CLANG_FULL=y), the following compilation error will appear: $ make LLVM=1 LLVM_IAS=1 -j ... ld.lld: error: ld-temp.o :26889:1: symbol 'cgroup_storage_map_btf_ids' is already defined cgroup_storage_map_btf_ids:; ^ make[1]: *** [/.../bpf-next/scripts/Makefile.vmlinux_o:61: vmlinux.o] Error 1 In local_storage.c, we have BTF_ID_LIST_SINGLE(cgroup_storage_map_btf_ids, struct, bpf_local_storage_map) Commit c4bcfb38a95e ("bpf: Implement cgroup storage available to non-cgroup-attached bpf progs") added the above identical BTF_ID_LIST_SINGLE definition in bpf_cgrp_storage.c. With duplicated definitions, llvm linker complains with lto build. Also, extracting btf_id of 'struct bpf_local_storage_map' is defined four times for sk, inode, task and cgrp local storages. Let us define a single global one with a different name than cgroup_storage_map_btf_ids, which also fixed the lto compilation error. Fixes: c4bcfb38a95e ("bpf: Implement cgroup storage available to non-cgroup-attached bpf progs") Signed-off-by: Yonghong Song Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20221130052147.1591625-1-yhs@fb.com --- include/linux/btf_ids.h | 1 + kernel/bpf/bpf_cgrp_storage.c | 3 +-- kernel/bpf/bpf_inode_storage.c | 4 +--- kernel/bpf/bpf_task_storage.c | 4 ++-- net/core/bpf_sk_storage.c | 3 +-- 5 files changed, 6 insertions(+), 9 deletions(-) (limited to 'kernel/bpf/bpf_inode_storage.c') diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index 93397711a68c..3a4f7cd882ca 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -266,5 +266,6 @@ MAX_BTF_TRACING_TYPE, extern u32 btf_tracing_ids[]; extern u32 bpf_cgroup_btf_id[]; +extern u32 bpf_local_storage_map_btf_id[]; #endif diff --git a/kernel/bpf/bpf_cgrp_storage.c b/kernel/bpf/bpf_cgrp_storage.c index 309403800f82..6cdf6d9ed91d 100644 --- a/kernel/bpf/bpf_cgrp_storage.c +++ b/kernel/bpf/bpf_cgrp_storage.c @@ -211,7 +211,6 @@ BPF_CALL_2(bpf_cgrp_storage_delete, struct bpf_map *, map, struct cgroup *, cgro return ret; } -BTF_ID_LIST_SINGLE(cgroup_storage_map_btf_ids, struct, bpf_local_storage_map) const struct bpf_map_ops cgrp_storage_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = bpf_local_storage_map_alloc_check, @@ -222,7 +221,7 @@ const struct bpf_map_ops cgrp_storage_map_ops = { .map_update_elem = bpf_cgrp_storage_update_elem, .map_delete_elem = bpf_cgrp_storage_delete_elem, .map_check_btf = bpf_local_storage_map_check_btf, - .map_btf_id = &cgroup_storage_map_btf_ids[0], + .map_btf_id = &bpf_local_storage_map_btf_id[0], .map_owner_storage_ptr = cgroup_storage_ptr, }; diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c index 6a1d4d22816a..05f4c66c9089 100644 --- a/kernel/bpf/bpf_inode_storage.c +++ b/kernel/bpf/bpf_inode_storage.c @@ -213,8 +213,6 @@ static void inode_storage_map_free(struct bpf_map *map) bpf_local_storage_map_free(map, &inode_cache, NULL); } -BTF_ID_LIST_SINGLE(inode_storage_map_btf_ids, struct, - bpf_local_storage_map) const struct bpf_map_ops inode_storage_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = bpf_local_storage_map_alloc_check, @@ -225,7 +223,7 @@ const struct bpf_map_ops inode_storage_map_ops = { .map_update_elem = bpf_fd_inode_storage_update_elem, .map_delete_elem = bpf_fd_inode_storage_delete_elem, .map_check_btf = bpf_local_storage_map_check_btf, - .map_btf_id = &inode_storage_map_btf_ids[0], + .map_btf_id = &bpf_local_storage_map_btf_id[0], .map_owner_storage_ptr = inode_storage_ptr, }; diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c index 8e832db8151a..1e486055a523 100644 --- a/kernel/bpf/bpf_task_storage.c +++ b/kernel/bpf/bpf_task_storage.c @@ -324,7 +324,7 @@ static void task_storage_map_free(struct bpf_map *map) bpf_local_storage_map_free(map, &task_cache, &bpf_task_storage_busy); } -BTF_ID_LIST_SINGLE(task_storage_map_btf_ids, struct, bpf_local_storage_map) +BTF_ID_LIST_GLOBAL_SINGLE(bpf_local_storage_map_btf_id, struct, bpf_local_storage_map) const struct bpf_map_ops task_storage_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = bpf_local_storage_map_alloc_check, @@ -335,7 +335,7 @@ const struct bpf_map_ops task_storage_map_ops = { .map_update_elem = bpf_pid_task_storage_update_elem, .map_delete_elem = bpf_pid_task_storage_delete_elem, .map_check_btf = bpf_local_storage_map_check_btf, - .map_btf_id = &task_storage_map_btf_ids[0], + .map_btf_id = &bpf_local_storage_map_btf_id[0], .map_owner_storage_ptr = task_storage_ptr, }; diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c index 9d2288c0736e..bb378c33f542 100644 --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -310,7 +310,6 @@ bpf_sk_storage_ptr(void *owner) return &sk->sk_bpf_storage; } -BTF_ID_LIST_SINGLE(sk_storage_map_btf_ids, struct, bpf_local_storage_map) const struct bpf_map_ops sk_storage_map_ops = { .map_meta_equal = bpf_map_meta_equal, .map_alloc_check = bpf_local_storage_map_alloc_check, @@ -321,7 +320,7 @@ const struct bpf_map_ops sk_storage_map_ops = { .map_update_elem = bpf_fd_sk_storage_update_elem, .map_delete_elem = bpf_fd_sk_storage_delete_elem, .map_check_btf = bpf_local_storage_map_check_btf, - .map_btf_id = &sk_storage_map_btf_ids[0], + .map_btf_id = &bpf_local_storage_map_btf_id[0], .map_local_storage_charge = bpf_sk_storage_charge, .map_local_storage_uncharge = bpf_sk_storage_uncharge, .map_owner_storage_ptr = bpf_sk_storage_ptr, -- cgit v1.2.3