On Sat, May 4, 2019 at 9:18 AM Masahiro Yamada yamada.masahiro@socionext.com wrote:

On Sat, May 4, 2019 at 3:27 AM Joel Fernandes (Google) joel@joelfernandes.org wrote:

...

The kheaders archive consisting of the kernel headers used for compiling bpf programs is in /proc. However there is concern that moving it here will make it permanent. Let us move it to /sys/kernel as discussed [1].

[1] https://lore.kernel.org/patchwork/patch/1067310/#1265969

Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org

---

This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/

kernel/kheaders.c | 40 ++++++++++++++++------------------------

Please rename CONFIG_IKHEADERS_PROC.

Thanks.

Please adjust Kconfig prompt. tristate "Enable kernel header artifacts through /proc/kheaders.tar.xz"

"depends on PROC_FS" -> "depends on SYSFS"

...

1 file changed, 16 insertions(+), 24 deletions(-)

diff --git a/kernel/kheaders.c b/kernel/kheaders.c index 70ae6052920d..6a16f8f6898d 100644 --- a/kernel/kheaders.c +++ b/kernel/kheaders.c @@ -8,9 +8,8 @@

#include <linux/kernel.h> #include <linux/module.h> -#include <linux/proc_fs.h> +#include <linux/kobject.h> #include <linux/init.h> -#include <linux/uaccess.h>

/*

• Define kernel_headers_data and kernel_headers_data_end, within which the

@@ -31,39 +30,32 @@ extern char kernel_headers_data; extern char kernel_headers_data_end;

static ssize_t -ikheaders_read_current(struct file *file, char __user *buf,

•                 size_t len, loff_t *offset)
  

+ikheaders_read(struct file *file, struct kobject *kobj,

•          struct bin_attribute *bin_attr,
  

•          char *buf, loff_t off, size_t len)
  

{

•   return simple_read_from_buffer(buf, len, offset,
  

•                                  &kernel_headers_data,
  

•                                  &kernel_headers_data_end -
  

•                                  &kernel_headers_data);
  

•   memcpy(buf, &kernel_headers_data + off, len);
  

•   return len;
  

}

-static const struct file_operations ikheaders_file_ops = {

•   .read = ikheaders_read_current,
  

•   .llseek = default_llseek,
  

+static struct bin_attribute kheaders_attr __ro_after_init = {

•   .attr = {
  

•           .name = "kheaders.tar.xz",
  

•           .mode = S_IRUGO,
  

•   },
  

•   .read = &ikheaders_read,
  

};

static int __init ikheaders_init(void) {

•   struct proc_dir_entry *entry;
  

•   /* create the current headers file */
  

•   entry = proc_create("kheaders.tar.xz", S_IRUGO, NULL,
  

•                       &ikheaders_file_ops);
  

•   if (!entry)
  

•           return -ENOMEM;
  

•   proc_set_size(entry,
  

•                 &kernel_headers_data_end -
  

•                 &kernel_headers_data);
  

•   return 0;
  

•   kheaders_attr.size = (&kernel_headers_data_end -
  

•                         &kernel_headers_data);
  

•   return sysfs_create_bin_file(kernel_kobj, &kheaders_attr);
  

}

static void __exit ikheaders_cleanup(void) {

•   remove_proc_entry("kheaders.tar.xz", NULL);
  

•   sysfs_remove_bin_file(kernel_kobj, &kheaders_attr);
  

}

module_init(ikheaders_init);

2.21.0.1020.gf2820cf01a-goog

-- Best Regards Masahiro Yamada