From 2f2665c13af4895b26761107c2f637c2f112d8e9 Mon Sep 17 00:00:00 2001 From: Joel Granados Date: Fri, 16 Jun 2023 10:59:22 +0200 Subject: sysctl: replace child with an enumeration This is part of the effort to remove the empty element at the end of ctl_table structs. "child" was a deprecated elem in this struct and was being used to differentiate between two types of ctl_tables: "normal" and "permanently emtpy". What changed?: * Replace "child" with an enumeration that will have two values: the default (0) and the permanently empty (1). The latter is left at zero so when struct ctl_table is created with kzalloc or in a local context, it will have the zero value by default. We document the new enum with kdoc. * Remove the "empty child" check from sysctl_check_table * Remove count_subheaders function as there is no longer a need to calculate how many headers there are for every child * Remove the recursive call to unregister_sysctl_table as there is no need to traverse down the child tree any longer * Add a new SYSCTL_PERM_EMPTY_DIR binary flag * Remove the last remanence of child from partport/procfs.c Signed-off-by: Joel Granados Signed-off-by: Luis Chamberlain --- include/linux/sysctl.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'include/linux/sysctl.h') diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 653b66c762b1..59d451f455bf 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -137,7 +137,17 @@ struct ctl_table { void *data; int maxlen; umode_t mode; - struct ctl_table *child; /* Deprecated */ + /** + * enum type - Enumeration to differentiate between ctl target types + * @SYSCTL_TABLE_TYPE_DEFAULT: ctl target with no special considerations + * @SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY: Used to identify a permanently + * empty directory target to serve + * as mount point. + */ + enum { + SYSCTL_TABLE_TYPE_DEFAULT, + SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY + } type; proc_handler *proc_handler; /* Callback for text formatting */ struct ctl_table_poll *poll; void *extra1; @@ -229,7 +239,7 @@ extern int unaligned_enabled; extern int unaligned_dump_stack; extern int no_unaligned_warning; -extern struct ctl_table sysctl_mount_point[]; +#define SYSCTL_PERM_EMPTY_DIR (1 << 0) #else /* CONFIG_SYSCTL */ -- cgit v1.2.3