linux-toradex.git/include/linux/fsnotify_backend.h, branch tegra-10.7.1

inotify: use GFP_NOFS under potential memory pressure

2009-07-21T19:26:27+00:00

inotify can have a watchs removed under filesystem reclaim.

=================================
[ INFO: inconsistent lock state ]
2.6.31-rc2 #16
---------------------------------
inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage.
khubd/217 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (iprune_mutex){+.+.?.}, at: [] invalidate_inodes+0x20/0xe3
{IN-RECLAIM_FS-W} state was registered at:
  [] __lock_acquire+0x2c9/0xac4
  [] lock_acquire+0x9f/0xc2
  [] __mutex_lock_common+0x2d/0x323
  [] mutex_lock_nested+0x2e/0x36
  [] shrink_icache_memory+0x38/0x1b2
  [] shrink_slab+0xe2/0x13c
  [] kswapd+0x3d1/0x55d
  [] kthread+0x66/0x6b
  [] kernel_thread_helper+0x7/0x10
  [] 0xffffffff

Two things are needed to fix this.  First we need a method to tell
fsnotify_create_event() to use GFP_NOFS and second we need to stop using
one global IN_IGNORED event and allocate them one at a time.  This solves
current issues with multiple IN_IGNORED on a queue having tail drop
problems and simplifies the allocations since we don't have to worry about
two tasks opperating on the IGNORED event concurrently.

Signed-off-by: Eric Paris

fs: allow d_instantiate to be called with negative parent dentry

2009-06-29T14:00:58+00:00

The new fsnotify infrastructure (starting at 90586523) causes an oops in
spufs, where we populate a directory with files before instantiating the
directory itself. The new changes seem to have introduced an assumption
that a dentry's parent will be positive when instantiating.

This change makes it once again possible to d_instantiate a dentry
with a negative parent, and brings __fsnotify_d_instantiate() into
line with inotify_d_instantiate(), which already has this NULL check.

Signed-off-by: Jeremy Kerr 
Signed-off-by: Eric Paris

inotify: reimplement inotify using fsnotify

2009-06-11T18:57:54+00:00

Reimplement inotify_user using fsnotify.  This should be feature for feature
exactly the same as the original inotify_user.  This does not make any changes
to the in kernel inotify feature used by audit.  Those patches (and the eventual
removal of in kernel inotify) will come after the new inotify_user proves to be
working correctly.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

fsnotify: handle filesystem unmounts with fsnotify marks

2009-06-11T18:57:54+00:00

When an fs is unmounted with an fsnotify mark entry attached to one of its
inodes we need to destroy that mark entry and we also (like inotify) send
an unmount event.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

fsnotify: allow groups to add private data to events

2009-06-11T18:57:54+00:00

inotify needs per group information attached to events.  This patch allows
groups to attach private information and implements a callback so that
information can be freed when an event is being destroyed.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

fsnotify: add correlations between events

2009-06-11T18:57:54+00:00

As part of the standard inotify events it includes a correlation cookie
between two dentry move operations.  This patch includes the same behaviour
in fsnotify events.  It is needed so that inotify userspace can be
implemented on top of fsnotify.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

fsnotify: include pathnames with entries when possible

2009-06-11T18:57:53+00:00

When inotify wants to send events to a directory about a child it includes
the name of the original file.  This patch collects that filename and makes
it available for notification.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

fsnotify: generic notification queue and waitq

2009-06-11T18:57:53+00:00

inotify needs to do asyc notification in which event information is stored
on a queue until the listener is ready to receive it.  This patch
implements a generic notification queue for inotify (and later fanotify) to
store events to be sent at a later time.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

dnotify: reimplement dnotify using fsnotify

2009-06-11T18:57:53+00:00

Reimplement dnotify using fsnotify.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig

fsnotify: parent event notification

2009-06-11T18:57:53+00:00

inotify and dnotify both use a similar parent notification mechanism.  We
add a generic parent notification mechanism to fsnotify for both of these
to use.  This new machanism also adds the dentry flag optimization which
exists for inotify to dnotify.

Signed-off-by: Eric Paris 
Acked-by: Al Viro 
Cc: Christoph Hellwig