From: Kui-Feng Lee <thinker.li@gmail.com>
To: bpf@vger.kernel.org, ast@kernel.org, martin.lau@linux.dev,
song@kernel.org, kernel-team@meta.com, andrii@kernel.org
Cc: sinquersw@gmail.com, kuifeng@meta.com,
Kui-Feng Lee <thinker.li@gmail.com>
Subject: [PATCH bpf-next 05/11] bpf: initialize/free array of btf_field(s).
Date: Tue, 9 Apr 2024 17:41:44 -0700 [thread overview]
Message-ID: <20240410004150.2917641-6-thinker.li@gmail.com> (raw)
In-Reply-To: <20240410004150.2917641-1-thinker.li@gmail.com>
Initialize and free each element in a btf_field array based on the values
of nelems and size in btf_field. The value of nelems is the length of the
flatten array for nested arrays.
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
---
include/linux/bpf.h | 7 +++++++
kernel/bpf/syscall.c | 39 ++++++++++++++++++++++++---------------
2 files changed, 31 insertions(+), 15 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f397ccdc6d4b..ee53dcd14bd4 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -390,6 +390,9 @@ static inline u32 btf_field_type_align(enum btf_field_type type)
static inline void bpf_obj_init_field(const struct btf_field *field, void *addr)
{
+ u32 elem_size;
+ int i;
+
memset(addr, 0, field->size);
switch (field->type) {
@@ -400,6 +403,10 @@ static inline void bpf_obj_init_field(const struct btf_field *field, void *addr)
RB_CLEAR_NODE((struct rb_node *)addr);
break;
case BPF_LIST_HEAD:
+ elem_size = field->size / field->nelems;
+ for (i = 0; i < field->nelems; i++, addr += elem_size)
+ INIT_LIST_HEAD((struct list_head *)addr);
+ break;
case BPF_LIST_NODE:
INIT_LIST_HEAD((struct list_head *)addr);
break;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index e44c276e8617..543ff0d944e8 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -672,6 +672,8 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj)
const struct btf_field *field = &fields[i];
void *field_ptr = obj + field->offset;
void *xchgd_field;
+ u32 elem_size = field->size / field->nelems;
+ int j;
switch (fields[i].type) {
case BPF_SPIN_LOCK:
@@ -680,35 +682,42 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj)
bpf_timer_cancel_and_free(field_ptr);
break;
case BPF_KPTR_UNREF:
- WRITE_ONCE(*(u64 *)field_ptr, 0);
+ for (j = 0; j < field->nelems; j++, field_ptr += elem_size)
+ WRITE_ONCE(*(u64 *)field_ptr, 0);
break;
case BPF_KPTR_REF:
case BPF_KPTR_PERCPU:
- xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0);
- if (!xchgd_field)
- break;
-
- if (!btf_is_kernel(field->kptr.btf)) {
+ if (!btf_is_kernel(field->kptr.btf))
pointee_struct_meta = btf_find_struct_meta(field->kptr.btf,
field->kptr.btf_id);
- migrate_disable();
- __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ?
- pointee_struct_meta->record : NULL,
- fields[i].type == BPF_KPTR_PERCPU);
- migrate_enable();
- } else {
- field->kptr.dtor(xchgd_field);
+
+ for (j = 0; j < field->nelems; j++, field_ptr += elem_size) {
+ xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0);
+ if (!xchgd_field)
+ continue;
+
+ if (!btf_is_kernel(field->kptr.btf)) {
+ migrate_disable();
+ __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ?
+ pointee_struct_meta->record : NULL,
+ fields[i].type == BPF_KPTR_PERCPU);
+ migrate_enable();
+ } else {
+ field->kptr.dtor(xchgd_field);
+ }
}
break;
case BPF_LIST_HEAD:
if (WARN_ON_ONCE(rec->spin_lock_off < 0))
continue;
- bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off);
+ for (j = 0; j < field->nelems; j++, field_ptr += elem_size)
+ bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off);
break;
case BPF_RB_ROOT:
if (WARN_ON_ONCE(rec->spin_lock_off < 0))
continue;
- bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off);
+ for (j = 0; j < field->nelems; j++, field_ptr += elem_size)
+ bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off);
break;
case BPF_LIST_NODE:
case BPF_RB_NODE:
--
2.34.1
next prev parent reply other threads:[~2024-04-10 0:42 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-10 0:41 [PATCH bpf-next 00/11] Enable BPF programs to declare arrays of kptr, bpf_rb_root, and bpf_list_head Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 01/11] bpf: Remove unnecessary checks on the offset of btf_field Kui-Feng Lee
2024-04-11 22:12 ` Eduard Zingerman
2024-04-10 0:41 ` [PATCH bpf-next 02/11] bpf: Remove unnecessary call to btf_field_type_size() Kui-Feng Lee
2024-04-11 22:12 ` Eduard Zingerman
2024-04-10 0:41 ` [PATCH bpf-next 03/11] bpf: Add nelems to struct btf_field_info and btf_field Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 04/11] bpf: check_map_kptr_access() compute the offset from the reg state Kui-Feng Lee
2024-04-11 22:13 ` Eduard Zingerman
2024-04-12 4:00 ` Kui-Feng Lee
2024-04-10 0:41 ` Kui-Feng Lee [this message]
2024-04-11 22:13 ` [PATCH bpf-next 05/11] bpf: initialize/free array of btf_field(s) Eduard Zingerman
2024-04-12 3:56 ` Kui-Feng Lee
2024-04-12 15:32 ` Eduard Zingerman
2024-04-12 17:00 ` Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 06/11] bpf: Find btf_field with the knowledge of arrays Kui-Feng Lee
2024-04-11 22:14 ` Eduard Zingerman
2024-04-12 2:00 ` Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 07/11] bpf: check_map_access() " Kui-Feng Lee
2024-04-11 22:14 ` Eduard Zingerman
2024-04-12 16:32 ` Kui-Feng Lee
2024-04-12 19:08 ` Eduard Zingerman
2024-04-12 19:29 ` Kui-Feng Lee
2024-04-12 19:50 ` Eduard Zingerman
2024-04-10 0:41 ` [PATCH bpf-next 08/11] bpf: Enable and verify btf_field arrays Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 09/11] selftests/bpf: Test global kptr arrays Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 10/11] selftests/bpf: Test global bpf_rb_root arrays Kui-Feng Lee
2024-04-10 0:41 ` [PATCH bpf-next 11/11] selftests/bpf: Test global bpf_list_head arrays Kui-Feng Lee
-- strict thread matches above, loose matches on Subject: below --
2024-04-11 3:39 [PATCH bpf-next 05/11] bpf: initialize/free array of btf_field(s) kernel test robot
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240410004150.2917641-6-thinker.li@gmail.com \
--to=thinker.li@gmail.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=kernel-team@meta.com \
--cc=kuifeng@meta.com \
--cc=martin.lau@linux.dev \
--cc=sinquersw@gmail.com \
--cc=song@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.