From 77992f896745c63ae64bfccfdc429ab7b3d88da5 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Wed, 23 Nov 2022 12:24:16 +0100 Subject: [PATCH] configfs: remove mentions of committable items A proposition of implementation of committable items has been rejected due to the gpio-sim module being the only user and configfs not getting much development in general. In that case, let's remove the notion of committable items from docs and headers. Signed-off-by: Bartosz Golaszewski Signed-off-by: Christoph Hellwig --- Documentation/filesystems/configfs.rst | 48 -------------------------- include/linux/configfs.h | 3 -- 2 files changed, 51 deletions(-) diff --git a/Documentation/filesystems/configfs.rst b/Documentation/filesystems/configfs.rst index 1d3d6f4a82a9..8c9342ed6d25 100644 --- a/Documentation/filesystems/configfs.rst +++ b/Documentation/filesystems/configfs.rst @@ -289,7 +289,6 @@ config_item_type:: const char *name); struct config_group *(*make_group)(struct config_group *group, const char *name); - int (*commit_item)(struct config_item *item); void (*disconnect_notify)(struct config_group *group, struct config_item *item); void (*drop_item)(struct config_group *group, @@ -486,50 +485,3 @@ up. Here, the heartbeat code calls configfs_depend_item(). If it succeeds, then heartbeat knows the region is safe to give to ocfs2. If it fails, it was being torn down anyway, and heartbeat can gracefully pass up an error. - -Committable Items -================= - -Note: - Committable items are currently unimplemented. - -Some config_items cannot have a valid initial state. That is, no -default values can be specified for the item's attributes such that the -item can do its work. Userspace must configure one or more attributes, -after which the subsystem can start whatever entity this item -represents. - -Consider the FakeNBD device from above. Without a target address *and* -a target device, the subsystem has no idea what block device to import. -The simple example assumes that the subsystem merely waits until all the -appropriate attributes are configured, and then connects. This will, -indeed, work, but now every attribute store must check if the attributes -are initialized. Every attribute store must fire off the connection if -that condition is met. - -Far better would be an explicit action notifying the subsystem that the -config_item is ready to go. More importantly, an explicit action allows -the subsystem to provide feedback as to whether the attributes are -initialized in a way that makes sense. configfs provides this as -committable items. - -configfs still uses only normal filesystem operations. An item is -committed via rename(2). The item is moved from a directory where it -can be modified to a directory where it cannot. - -Any group that provides the ct_group_ops->commit_item() method has -committable items. When this group appears in configfs, mkdir(2) will -not work directly in the group. Instead, the group will have two -subdirectories: "live" and "pending". The "live" directory does not -support mkdir(2) or rmdir(2) either. It only allows rename(2). The -"pending" directory does allow mkdir(2) and rmdir(2). An item is -created in the "pending" directory. Its attributes can be modified at -will. Userspace commits the item by renaming it into the "live" -directory. At this point, the subsystem receives the ->commit_item() -callback. If all required attributes are filled to satisfaction, the -method returns zero and the item is moved to the "live" directory. - -As rmdir(2) does not work in the "live" directory, an item must be -shutdown, or "uncommitted". Again, this is done via rename(2), this -time from the "live" directory back to the "pending" one. The subsystem -is notified by the ct_group_ops->uncommit_object() method. diff --git a/include/linux/configfs.h b/include/linux/configfs.h index 97cfd13bae51..2606711adb18 100644 --- a/include/linux/configfs.h +++ b/include/linux/configfs.h @@ -204,8 +204,6 @@ static struct configfs_bin_attribute _pfx##attr_##_name = { \ * group children. default_groups may coexist alongsize make_group() or * make_item(), but if the group wishes to have only default_groups * children (disallowing mkdir(2)), it need not provide either function. - * If the group has commit(), it supports pending and committed (active) - * items. */ struct configfs_item_operations { void (*release)(struct config_item *); @@ -216,7 +214,6 @@ struct configfs_item_operations { struct configfs_group_operations { struct config_item *(*make_item)(struct config_group *group, const char *name); struct config_group *(*make_group)(struct config_group *group, const char *name); - int (*commit_item)(struct config_item *item); void (*disconnect_notify)(struct config_group *group, struct config_item *item); void (*drop_item)(struct config_group *group, struct config_item *item); }; -- 2.39.5