Re: [PATCH 09/13] firmware_loader: simplify sysctl declaration with register_sysctl_subdir()
From: Greg KH <gregkh@linuxfoundation.org>
Date: 2020-05-29 10:26:17
Also in:
dri-devel, intel-gfx, lkml, ocfs2-devel
On Fri, May 29, 2020 at 07:41:04AM +0000, Luis Chamberlain wrote:
From: Xiaoming Ni <redacted> Move the firmware config sysctl table to fallback_table.c and use the new register_sysctl_subdir() helper. This removes the clutter from kernel/sysctl.c. Signed-off-by: Xiaoming Ni <redacted> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> --- drivers/base/firmware_loader/fallback.c | 4 ++++ drivers/base/firmware_loader/fallback.h | 11 ++++++++++ drivers/base/firmware_loader/fallback_table.c | 22 +++++++++++++++++-- include/linux/sysctl.h | 1 - kernel/sysctl.c | 7 ------ 5 files changed, 35 insertions(+), 10 deletions(-)
So it now takes more lines than the old stuff? :(
quoted hunk ↗ jump to hunk
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index d9ac7296205e..8190653ae9a3 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c@@ -200,12 +200,16 @@ static struct class firmware_class = { int register_sysfs_loader(void) { + int ret = register_firmware_config_sysctl(); + if (ret != 0) + return ret;
checkpatch :(
return class_register(&firmware_class);
And if that fails?
quoted hunk ↗ jump to hunk
} void unregister_sysfs_loader(void) { class_unregister(&firmware_class); + unregister_firmware_config_sysctl(); } static ssize_t firmware_loading_show(struct device *dev,diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h index 06f4577733a8..7d2cb5f6ceb8 100644 --- a/drivers/base/firmware_loader/fallback.h +++ b/drivers/base/firmware_loader/fallback.h@@ -42,6 +42,17 @@ void fw_fallback_set_default_timeout(void); int register_sysfs_loader(void); void unregister_sysfs_loader(void); +#ifdef CONFIG_SYSCTL +extern int register_firmware_config_sysctl(void); +extern void unregister_firmware_config_sysctl(void); +#else +static inline int register_firmware_config_sysctl(void) +{ + return 0; +} +static inline void unregister_firmware_config_sysctl(void) { } +#endif /* CONFIG_SYSCTL */ + #else /* CONFIG_FW_LOADER_USER_HELPER */ static inline int firmware_fallback_sysfs(struct firmware *fw, const char *name, struct device *device,diff --git a/drivers/base/firmware_loader/fallback_table.c b/drivers/base/firmware_loader/fallback_table.c index 46a731dede6f..4234aa5ee5df 100644 --- a/drivers/base/firmware_loader/fallback_table.c +++ b/drivers/base/firmware_loader/fallback_table.c@@ -24,7 +24,7 @@ struct firmware_fallback_config fw_fallback_config = { EXPORT_SYMBOL_NS_GPL(fw_fallback_config, FIRMWARE_LOADER_PRIVATE); #ifdef CONFIG_SYSCTL -struct ctl_table firmware_config_table[] = { +static struct ctl_table firmware_config_table[] = { { .procname = "force_sysfs_fallback", .data = &fw_fallback_config.force_sysfs_fallback,@@ -45,4 +45,22 @@ struct ctl_table firmware_config_table[] = { }, { } }; -#endif + +static struct ctl_table_header *hdr; +int register_firmware_config_sysctl(void) +{ + if (hdr) + return -EEXIST;
How can hdr be set?
+ hdr = register_sysctl_subdir("kernel", "firmware_config",
+ firmware_config_table);
+ if (!hdr)
+ return -ENOMEM;
+ return 0;
+}
+
+void unregister_firmware_config_sysctl(void)
+{
+ if (hdr)
+ unregister_sysctl_table(hdr);Why can't unregister_sysctl_table() take a null pointer value? And what sets 'hdr' (worst name for a static variable) to NULL so that it knows not to be unregistered again as it looks like register_firmware_config_sysctl() could be called multiple times. thanks, greg k-h