WSL2-Linux-Kernel/include
Tejun Heo ba7443bc65 sysfs, kernfs: implement kernfs_create/destroy_root()
There currently is single kernfs hierarchy in the whole system which
is used for sysfs.  kernfs needs to support multiple hierarchies to
allow other users.  This patch introduces struct kernfs_root which
serves as the root of each kernfs hierarchy and implements
kernfs_create/destroy_root().

* Each kernfs_root is associated with a root sd (sysfs_dentry).  The
  root is freed when the root sd is released and kernfs_destory_root()
  simply invokes kernfs_remove() on the root sd.  sysfs_remove_one()
  is updated to handle release of the root sd.  Note that ps_iattr
  update in sysfs_remove_one() is trivially updated for readability.

* Root sd's are now dynamically allocated using sysfs_new_dirent().
  Update sysfs_alloc_ino() so that it gives out ino from 1 so that the
  root sd still gets ino 1.

* While kernfs currently only points to the root sd, it'll soon grow
  fields which are specific to each hierarchy.  As determining a given
  sd's root will be necessary, sd->s_dir.root is added.  This backlink
  fits better as a separate field in sd; however, sd->s_dir is inside
  union with space to spare, so use it to save space and provide
  kernfs_root() accessor to determine the root sd.

* As hierarchies may be destroyed now, each mount needs to hold onto
  the hierarchy it's attached to.  Update sysfs_fill_super() and
  sysfs_kill_sb() so that they get and put the kernfs_root
  respectively.

* sysfs_root is replaced with kernfs_root which is dynamically created
  by invoking kernfs_create_root() from sysfs_init().

This patch doesn't introduce any visible behavior changes.

v2: kernfs_create_root() forgot to set @sd->priv.  Fixed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-29 18:10:48 -08:00
..
acpi Merge branch 'acpica' 2013-11-27 01:03:27 +01:00
asm-generic Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2013-11-23 16:18:25 -08:00
clocksource
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2013-11-23 16:18:25 -08:00
drm Merge branch 'ttm-fixes-3.13' of git://people.freedesktop.org/~thomash/linux into drm-fixes 2013-11-21 18:46:56 +10:00
dt-bindings For the 3.13 merge window we have a couple of new drivers for the AMS 2013-11-15 16:37:40 -08:00
keys
kvm
linux sysfs, kernfs: implement kernfs_create/destroy_root() 2013-11-29 18:10:48 -08:00
math-emu
media Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2013-11-18 15:50:07 -08:00
memory
misc
net genetlink: fix genl_set_err() group ID 2013-11-21 13:09:43 -05:00
pcmcia
ras
rdma Merge branches 'cma', 'cxgb4', 'flowsteer', 'ipoib', 'misc', 'mlx4', 'mlx5', 'nes', 'ocrdma', 'qib' and 'srp' into for-next 2013-11-17 08:22:19 -08:00
rxrpc
scsi Main batch of InfiniBand/RDMA changes for 3.13: 2013-11-18 15:36:04 -08:00
sound Merge remote-tracking branch 'asoc/topic/twl4030' into asoc-next 2013-11-08 10:43:40 +00:00
target target_core_alua: Store supported ALUA states 2013-11-20 11:26:37 -08:00
trace tracing: Allow events to have NULL strings 2013-11-26 10:34:46 -05:00
uapi Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2013-11-22 10:56:11 -08:00
video fbdev changes for 3.13 2013-11-14 14:44:20 +09:00
xen Features: 2013-11-15 13:34:37 +09:00
Kbuild