WSL2-Linux-Kernel/fs/sysfs
NeilBrown 4508a7a734 [PATCH] sysfs: Allow sysfs attribute files to be pollable
It works like this:
  Open the file
  Read all the contents.
  Call poll requesting POLLERR or POLLPRI (so select/exceptfds works)
  When poll returns,
     close the file and go to top of loop.
   or lseek to start of file and go back to the 'read'.

Events are signaled by an object manager calling
   sysfs_notify(kobj, dir, attr);

If the dir is non-NULL, it is used to find a subdirectory which
contains the attribute (presumably created by sysfs_create_group).

This has a cost of one int  per attribute, one wait_queuehead per kobject,
one int per open file.

The name "sysfs_notify" may be confused with the inotify
functionality.  Maybe it would be nice to support inotify for sysfs
attributes as well?

This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action
to be pollable

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-04-14 11:41:24 -07:00
..
Makefile Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
bin.c [PATCH] Make most file operations structs in fs/ const 2006-03-28 09:16:06 -08:00
dir.c [PATCH] sysfs: Allow sysfs attribute files to be pollable 2006-04-14 11:41:24 -07:00
file.c [PATCH] sysfs: Allow sysfs attribute files to be pollable 2006-04-14 11:41:24 -07:00
group.c [PATCH] remove duplicate get_dentry functions in various places 2005-06-23 09:45:20 -07:00
inode.c BUG_ON() Conversion in fs/sysfs/ 2006-04-01 01:18:38 +02:00
mount.c [PATCH] sysfs-iattr: set inode attributes 2005-06-20 15:15:37 -07:00
symlink.c [PATCH] sysfs: fix a kobject leak in sysfs_add_link on the error path 2006-03-20 13:42:59 -08:00
sysfs.h [PATCH] sysfs: Allow sysfs attribute files to be pollable 2006-04-14 11:41:24 -07:00