linux.git/fs/sysfs/sysfs.h, branch v3.10

sysfs: Functions for adding/removing symlinks to/from attribute groups

2013-01-25T20:51:13+00:00

The most convenient way to expose ACPI power resources lists of a
device is to put symbolic links to sysfs directories representing
those resources into special attribute groups in the device's sysfs
directory.  For this purpose, it is necessary to be able to add
symbolic links to attribute groups.

For this reason, add sysfs helper functions for adding/removing
symbolic links to/from attribute groups, sysfs_add_link_to_group()
and sysfs_remove_link_from_group(), respectively.

This change set includes a build fix from David Rientjes.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Greg Kroah-Hartman

sysfs: switch to ->s_d_op and ->d_release()

2012-07-14T12:35:06+00:00

a) ->d_iput() is wrong here - what we do to inode is completely usual, it's
dentry->d_fsdata that we want to drop.  Just use ->d_release().

b) switch to ->s_d_op - no need to play with d_set_d_op()

Signed-off-by: Al Viro

Revert "sysfs: Kill nlink counting."

2012-03-08T21:03:10+00:00

This reverts commit 524b6c5b39b931311dfe5a2f5abae2f5c9731676.

It has shown to break userspace tools, which is not acceptable.

Reported-by: Jiri Slaby 
Cc: Eric W. Biederman 
Cc: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

sysfs: Kill nlink counting.

2012-01-24T20:41:46+00:00

Tracking the number of subdirectories requires an extra field that increases
the size of sysfs_dirent.  nlinks are not particularly interesting for sysfs
and the nlink counts are wrong when network namespaces are involved so stop
counting them, and always return nlink == 1.  Userspace already knows that
directories with nlink == 1 have an nlink count they can't use to count
subdirectories.

This reduces the size of sysfs_dirent by 8 bytes on 64bit platforms.

Signed-off-by: Eric W. Biederman 
Signed-off-by: Greg Kroah-Hartman

sysfs: Store the sysfs inode in an unsigned int.

2012-01-24T20:41:46+00:00

Store the sysfs inode number in an unsided int because
ida inode allocator can return at most a 31 bit number,
reducing the size of struct sysfs_dirent by 8 bytes
on 64bit platforms.

Signed-off-by: Eric W. Biederman 
Signed-off-by: Greg Kroah-Hartman

sysfs: Reduce s_flags to an unsinged short so it packs well with s_mode

2012-01-24T20:41:00+00:00

On 32bit this reduces sizeof(struct sysfs_dirent) by 2 bytes.

Signed-off-by: Eric W. Biederman 
Signed-off-by: Greg Kroah-Hartman

sysfs: Add s_hash to sysfs_dirent and order directory entries by hash

2012-01-24T20:36:17+00:00

Compute a 31 bit hash of directory entries (that can fit in a signed
32bit off_t) and index the sysfs directory entries by that hash,
replacing the per directory indexes by name and by inode.  Because we
now only use a single rbtree this reduces the size of sysfs_dirent by 2
pointers.  Because we have fewer cases to deal with the code is now
simpler.

For now I use the simple hash that the dcache uses as that is easy to
use and seems simple enough.

In addition to makeing the code simpler using a hash for the file
position in readdir brings sysfs in line with other filesystems that
have non-trivial directory structures.

Signed-off-by: Eric W. Biederman 
Signed-off-by: Greg Kroah-Hartman

sysfs: propagate umode_t

2012-01-04T03:55:03+00:00

Signed-off-by: Al Viro

sysfs: use rb-tree for inode number lookup

2011-08-23T00:43:53+00:00

sysfs: use rb-tree for inode number lookup

This patch makes sysfs use red-black tree for inode number lookup.
Together with a previous patch to use red-black tree for name lookup,
this patch makes all sysfs lookups to have O(log n) complexity.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Greg Kroah-Hartman

sysfs: remove s_sibling hacks

2011-08-23T00:43:52+00:00

sysfs: remove s_sibling hacks

s_sibling was used for three different purposes:
1) as a linked list of entries in the directory
2) as a linked list of entries to be deleted
3) as a pointer to "struct completion"

This patch removes the hack and introduces new union u which
holds pointers for cases 2) and 3).

This change is needed for the following patch that removes s_sibling at all
and replaces it with a rb tree.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Greg Kroah-Hartman