linux/include
Tejun Heo f6acf8bb6a sysfs, kernfs: introduce kernfs_ops
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly.  This patch
introduces kernfs_ops which hosts methods kernfs users implement and
updates fs/sysfs/file.c such that sysfs_kf_*() functions populate
kernfs_ops and kernfs_file_*() functions call the matching entries
from kernfs_ops.

kernfs_ops contains the following groups of methods.

* seq_show() - for kernfs files which use seq_file for reads.

* read() - for direct read implementations.  Used iff seq_show() is
  not implemented.

* write() - for writes.

* mmap() - for mmaps.

Notes:

* sysfs_elem_attr->ops is added so that kernfs_ops can be accessed
  from sysfs_dirent.  kernfs_ops() helper is added to verify locking
  and access the field.

* SYSFS_FLAG_HAS_(SEQ_SHOW|MMAP) added.  sd->s_attr->ops is accessible
  only while holding active_ref and there are cases where we want to
  take different actions depending on which ops are implemented.
  These two flags cache whether the two ops are implemented for those.

* kernfs_file_*() no longer test sysfs type but chooses different
  behaviors depending on which methods in kernfs_ops are implemented.
  The conversions are trivial except for the open path.  As
  kernfs_file_open() now decides whether to allow read/write accesses
  depending on the kernfs_ops implemented, the presence of methods in
  kobjs and attribute_bin should be propagated to kernfs_ops.
  sysfs_add_file_mode_ns() is updated so that it propagates presence /
  absence of the callbacks through _empty, _ro, _wo, _rw kernfs_ops.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-29 17:35:05 -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: introduce kernfs_ops 2013-11-29 17:35:05 -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