[PATCH v2 2/3] btf: Switch vmlinux BTF attribute to sysfs_bin_attr_simple_read()

Thomas Weißschuh
2024-12-28T08:43:48Z

The generic function from the sysfs core can replace the custom one.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
---
This is a replacement for [0], as Alexei was not happy about BIN_ATTR_SIMPLE_RO()

[0] https://lore.kernel.org/lkml/20241122-sysfs-const-bin_attr-bpf-v1-1-823aea399b53@weissschuh.net/
---
kernel/bpf/sysfs_btf.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/kernel/bpf/sysfs_btf.c b/kernel/bpf/sysfs_btf.c
index fedb54c94cdb830a4890d33677dcc5a6e236c13f..81d6cf90584a7157929c50f62a5c6862e7a3d081 100644
--- a/kernel/bpf/sysfs_btf.c
+++ b/kernel/bpf/sysfs_btf.c
@@ -12,24 +12,16 @@
extern char __start_BTF[];
extern char __stop_BTF[];

-static ssize_t
-btf_vmlinux_read(struct file *file, struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buf, loff_t off, size_t len)
-{
- memcpy(buf, __start_BTF + off, len);
- return len;
-}
-
static struct bin_attribute bin_attr_btf_vmlinux __ro_after_init = {
.attr = { .name = "vmlinux", .mode = 0444, },
- .read = btf_vmlinux_read,
+ .read_new = sysfs_bin_attr_simple_read,
};

struct kobject *btf_kobj;

static int __init btf_vmlinux_init(void)
{
+ bin_attr_btf_vmlinux.private = __start_BTF;
bin_attr_btf_vmlinux.size = __stop_BTF - __start_BTF;

if (bin_attr_btf_vmlinux.size == 0)

--
2.47.1