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Commit Graph

196699 Commits

Author SHA1 Message Date
Jan Kara
03f4d804a1 jbd: Provide function to check whether transaction will issue data barrier
Provide a function which returns whether a transaction with given tid
will send a barrier to the filesystem device. The function will be used
by ext3 to detect whether fsync needs to send a separate barrier or not.

Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:40 +02:00
Dmitry Monakhov
311b9549ed ufs: add ufs speciffic ->setattr call
generic setattr not longer responsible for quota transfer.
use ufs_setattr for all ufs's inodes.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:40 +02:00
Jan Blunck
e0a5cbac02 BKL: Remove BKL from ext2 filesystem
The BKL is still used in ext2_put_super(), ext2_fill_super(), ext2_sync_fs()
ext2_remount() and ext2_write_inode(). From these calls ext2_put_super(),
ext2_fill_super() and ext2_remount() are protected against each other by
the struct super_block s_umount rw semaphore. The call in ext2_write_inode()
could only protect the modification of the ext2_sb_info through
ext2_update_dynamic_rev() against concurrent ext2_sync_fs() or ext2_remount().
ext2_fill_super() and ext2_put_super() can be left out because you need a
valid filesystem reference in all three cases, which you do not have when
you are one of these functions.

If the BKL is only protecting the modification of the ext2_sb_info it can
safely be removed since this is protected by the struct ext2_sb_info s_lock.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:40 +02:00
Jan Blunck
c15271f4e7 ext2: Add ext2_sb_info s_lock spinlock
Add a spinlock that protects against concurrent modifications of
s_mount_state, s_blocks_last, s_overhead_last and the content of the
superblock's buffer pointed to by sbi->s_es. The spinlock is now used in
ext2_xattr_update_super_block() which was setting the
EXT2_FEATURE_COMPAT_EXT_ATTR flag on the superblock without protection
before. Likewise the spinlock is used in ext2_show_options() to have a
consistent view of the mount options.

This is a preparation patch for removing the BKL from ext2 in the next
patch.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jan Kara <jack@suse.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:39 +02:00
Jan Blunck
4c96a68bfc ext2: Move ext2_write_super() out of ext2_setup_super()
Move ext2_write_super() out of ext2_setup_super() as a preparation for the
next patch that adds a new lock for superblock fields.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:39 +02:00
Jan Blunck
ee6921ebd0 ext2: Fold ext2_commit_super() into ext2_sync_super()
Both function originally did similar things except that ext2_sync_super()
is returning after the call to sync_dirty_buffer(sbh). Therefore this
patch adds a wait flag to tell ext2_sync_super() if it has to call
sync_dirty_buffer() to wait for in-progress I/O to finish.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:39 +02:00
Jan Blunck
20da9baf4c ext2: Remove duplicate code from ext2_sync_fs()
Depending in the state (valid or unchecked) of the filesystem either
ext2_sync_super() or ext2_commit_super() is called. If the filesystem is
currently valid (it is checked), we first mark it unchecked and afterwards
duplicate the work that ext2_sync_super() is doing later. Therefore this
patch removes the duplicate code and calls ext2_sync_super() directly after
marking the filesystem unchecked.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:39 +02:00
Jan Blunck
269c8db30c ext2: Set the write time in ext2_sync_fs()
This is probably a typo since the write time should actually be updated by
ext2_sync_fs() instead of the mount time.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:38 +02:00
Jan Blunck
2b8120efb2 ext2: Use ext2_clear_super_error() in ext2_sync_fs()
ext2_sync_fs() used to duplicate the code from ext2_clear_super_error().

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:38 +02:00
Dmitry Monakhov
41d1a636b8 ext3: init statistics after journal recovery v2
Currently block/inode/dir counters are initialized before journal was
recovered. In fact after journal recovery this info will probably
change which results in incorrect numbers returned from statfs(2).
BUG:#15768

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:38 +02:00
Francis Moreau
524e4a1d10 ext2: remove useless call to brelse() in ext2_free_inode()
This patch removes a useless call to brelse(bitmap_bh) since at that
point bitmap_bh is NULL and slightly cleans up bitmap_bh handling.

Signed-off-by: Francis Moreau <francis.moro@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:37 +02:00
Dmitry Monakhov
eabf290d14 quota: optimize mark_dirty logic
- Skip locking if quota is dirty already.
- Return old quota state to help fs-specciffic implementation to optimize
  case where quota was dirty already.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:37 +02:00
Jan Kara
4689153237 ext2: Avoid loading bitmaps for full groups during block allocation
There is no point in loading bitmap for groups which are completely full.
This causes noticeable performance problems (and memory pressure) on small
systems with large full filesystem
(http://marc.info/?l=linux-ext4&m=126843108314310&w=2).

Port of the same ext3 patch.

Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:37 +02:00
Frans van de Wiel
8cef107a1d ext3: Avoid loading bitmaps for full groups during block allocation
There is no point in loading bitmap for groups which are completely full.
This causes noticeable performance problems (and memory pressure) on small
systems with large full filesystem
(http://marc.info/?l=linux-ext4&m=126843108314310&w=2).

Jan Kara: Added a comment and changed check to use cpu-endian value.

Signed-off-by: "Frans van de Wiel" <fvdw@fvdw.eu>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:36 +02:00
Linus Torvalds
70ca0a42fe Fix networking tree iscsi_tcp.c mis-merge
The removal of the 'waitqueue_active()' test in commit d7d05548a6
("[SCSI] iscsi_tcp: fix relogin/shutdown hang") got incorrectly resolved
by David when he back-merged the main git tree into the networking tree
in commit 278554bd65 ("Merge branch 'master' of master.kernel.org:...").

There was a content conflict due to 'sock->sk->sk_sleep' being changed
into 'sk_sleep(sock->sk)' in the networking tree, but David didn't pick
up the iscsi change from the main tree.

Reported-by: James Bottomley <James.Bottomley@suse.de>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-21 09:48:36 -07:00
Chase Douglas
7c4fda1aa1 i2c-nforce2: Remove redundant error messages on ACPI conflict
The ACPI subsystem strictly checks for resource conflicts. When there's
a conflict, it outputs a warning message with all the details needed to
properly diagnose the underlying issue. However, the i2c-nforce2 driver
also prints its own message. Not only is the message redundant, it is at
the KERN_ERR level, which overrides some bootsplash screens for no good
reason. This change removes the two lines that print out the error
messages.

Signed-off-by: Chase Douglas <chase.douglas@canonical.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:41:01 +02:00
H Hartley Sweeten
2178218027 i2c: Use <linux/io.h> instead of <asm/io.h>
As warned by checkpatch.pl, <linux/io.h> should be used instead of
<asm/io.h>.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:41:01 +02:00
Farid Hammane
2086ca482f i2c-algo-pca: Fix coding style issues
Fix up some coding style issues. i2c-algo-pca.c has been built
successfully after applying this patch and the binary object is
still exactly the same. Other issues found by checkpatch.pl were
voluntarily not fixed, either to keep readability, or because of
false positive errors.

Signed-off-by: Farid Hammane <farid.hammane@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:41:00 +02:00
Farid Hammane
ae5624fc36 i2c-dev: Fix all coding style issues
Fix all coding style issues found by checkpatch.pl.

Signed-off-by: Farid Hammane <farid.hammane@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:40:59 +02:00
Farid Hammane
7225acf4aa i2c-core: Fix some coding style issues
Fix up coding style issues found by the checkpatch.pl tool.

Signed-off-by: Farid Hammane <farid.hammane@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:40:58 +02:00
Marek Szyprowski
b868078487 i2c-gpio: Move initialization code to subsys_initcall()
GPIO driven I2C bus can be used for controlling the PMIC chip. The
example of such configuration is Samsung Aquila board.

This patch moves initialization code to subsys_initcall() to ensure
that the i2c bus is available early so the regulators can be quickly
probed and available for other devices on their probe() call.

Such solution has been proposed by Mark Brown to fix the problem of
the regulators not beeing available on the peripheral device probe():
http://lists.infradead.org/pipermail/linux-arm-kernel/2010-March/011971.html

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:40:58 +02:00
Jean Delvare
bfdcad902f i2c-parport: Make template structure const
parport_algo_data is a template so it can be marked const.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:40:57 +02:00
H Hartley Sweeten
0be16c3061 i2c-dev: Remove unnecessary casts
The private_data member of struct file is a void *, there is no need
to cast it.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:40:57 +02:00
Jean Delvare
7aeb96642f at24: Fall back to byte or word reads if needed
Increase the portability of the at24 driver by letting it read from
EEPROM chips connected to cheap SMBus controllers that support neither
raw I2C messages nor even I2C block reads. All SMBus controllers
should support either word reads or byte reads, so read support
becomes universal, much like with the legacy "eeprom" driver.

Obviously, this only works with EEPROM chips up to AT24C16, that use
8-bit offset addressing. 16-bit offset addressing is almost impossible
to support on SMBus controllers.

I did not add universal support for writes, as I had no immediate need
for this, but it could be added later if needed (with the same
performance issue as byte and word reads have, of course.)

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Konstantin Lazarev <klazarev@sbcglobal.net>
2010-05-21 18:40:57 +02:00
Jean Delvare
c5aa69285c i2c-stub: Expose the default functionality flags
It is easier to adjust the flags when you know their default value.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
2010-05-21 18:40:56 +02:00
Jean Delvare
e624dbd324 i2c/scx200_acb: Make PCI device ids constant
Make PCI device ids constant as we just did for many other i2c bus
drivers already.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Márton Németh <nm127@freemail.hu>
2010-05-21 18:40:56 +02:00
Ivo Manca
3fb21c64b6 i2c-i801: Fix all checkpatch warnings
Fix all checkpatch warnings. No functional changes are made.

Signed-off-by: Ivo Manca <pinkel@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-05-21 18:40:55 +02:00
Jean Delvare
e0e8398c7a i2c-i801: All newer devices have all the optional features
Only the oldest devices lack some of the features supported by this
driver. List them explicitly, and default to all features enabled for
all other chips, including the ones added through sysfs. This will
make future driver maintenance easier.

In the unlikely event of a not yet supported device not implementing
all the features, one can always use the disable_features module
parameter to prevent the driver from attempting to use them.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Seth Heasley <seth.heasley@intel.com>
2010-05-21 18:40:55 +02:00
Jean Delvare
adff687d8c i2c-i801: Let the user disable selected driver features
Let the user disable selected features normally supported by the
device. This makes it possible to work around possible driver or
hardware bugs if the feature in question doesn't work as intended
for whatever reason.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Felix Rubinstein <felixru@gmail.com>
2010-05-21 18:40:54 +02:00
Eric W. Biederman
a1b3f594dc net: Expose all network devices in a namespaces in sysfs
This reverts commit aaf8cdc34d.

Drivers like the ipw2100 call device_create_group when they
are initialized and device_remove_group when they are shutdown.
Moving them between namespaces deletes their sysfs groups early.

In particular the following call chain results.
netdev_unregister_kobject -> device_del -> kobject_del -> sysfs_remove_dir
With sysfs_remove_dir recursively deleting all of it's subdirectories,
and nothing adding them back.

Ouch!

Therefore we need to call something that ultimate calls sysfs_mv_dir
as that sysfs function can move sysfs directories between namespaces
without deleting their subdirectories or their contents.   Allowing
us to avoid placing extra boiler plate into every driver that does
something interesting with sysfs.

Currently the function that provides that capability is device_rename.
That is the code works without nasty side effects as originally written.

So remove the misguided fix for moving devices between namespaces.  The
bug in the kobject layer that inspired it has now been recognized and
fixed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:34 -07:00
Eric W. Biederman
417daa1e8f hotplug: netns aware uevent_helper
It only makes sense for uevent_helper to get events
in the intial namespaces.  It's invocation is not
per namespace and it is not clear how we could make
it's invocation namespace aware.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:33 -07:00
Eric W. Biederman
5f71a29629 kobj: Send hotplug events in the proper namespace.
Utilize netlink_broacast_filtered to allow sending hotplug events
in the proper namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:32 -07:00
Eric W. Biederman
910a7e905f netlink: Implment netlink_broadcast_filtered
When netlink sockets are used to convey data that is in a namespace
we need a way to select a subset of the listening sockets to deliver
the packet to.  For the network namespace we have been doing this
by only transmitting packets in the correct network namespace.

For data belonging to other namespaces netlink_bradcast_filtered
provides a mechanism that allows us to examine the destination
socket and to decide if we should transmit the specified packet
to it.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:32 -07:00
Eric W. Biederman
d6523ddf23 net/sysfs: Fix the bitrot in network device kobject namespace support
I had a couple of stupid bugs in:
netns: Teach network device kobjects which namespace they are in.

- I duplicated the Kconfig for the NET_NS
- The build was broken when sysfs was not compiled in

The sysfs breakage is because after I moved the operations
for the sysfs to the kobject layer, to make things cleaner
I forgot to move the ifdefs.  Opps.

I'm not quite certain how I got introduced a second NET_NS Kconfig,
but it was probably a 3 way merge somewhere along the way that
did not notice that the NET_NS Kconfig option had mvoed and thout
that was a bug.  It probably slipped in because it used to be the
sysfs patches were the first patches in my network namespace patches.
Some things just don't go like you would expect.

Neither of these bugs actually affect anything in the common case
but they should be fixed.

Thanks to Serge for noticing they were present.

Reported-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: David S. Miller <davem@davemloft.net>
2010-05-21 09:37:32 -07:00
Eric W. Biederman
608b4b9548 netns: Teach network device kobjects which namespace they are in.
The problem.  Network devices show up in sysfs and with the network
namespace active multiple devices with the same name can show up in
the same directory, ouch!

To avoid that problem and allow existing applications in network namespaces
to see the same interface that is currently presented in sysfs, this
patch enables the tagging directory support in sysfs.

By using the network namespace pointers as tags to separate out the
the sysfs directory entries we ensure that we don't have conflicts
in the directories and applications only see a limited set of
the network devices.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:32 -07:00
Eric W. Biederman
07e98962fa kobject: Send hotplug events in all network namespaces
Open a copy of the uevent kernel socket in each network
namespace so we can send uevents in all network namespaces.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:32 -07:00
Christoph Egger
1d9e882ba4 driver-core: fix Typo in drivers/base/core.c for CONFIG_MODULE
In this code section the final S of CONFIG_MODULES was missed making
the whole check useless

Signed-off-by: Christoph Egger <siccegge@cs.fau.de>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:32 -07:00
Chris Wright
de139a3393 pci: check caps from sysfs file open to read device dependent config space
The PCI config space bin_attr read handler has a hardcoded CAP_SYS_ADMIN
check to verify privileges before allowing a user to read device
dependent config space.  This is meant to protect from an unprivileged
user potentially locking up the box.

When assigning a PCI device directly to a guest with libvirt and KVM,
the sysfs config space file is chown'd to the unprivileged user that
the KVM guest will run as.  The guest needs to have full access to the
device's config space since it's responsible for driving the device.
However, despite being the owner of the sysfs file, the CAP_SYS_ADMIN
check will not allow read access beyond the config header.

With this patch we check privileges against the capabilities used when
openining the sysfs file.  The allows a privileged process to open the
file and hand it to an unprivileged process, and the unprivileged process
can still read all of the config space.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:32 -07:00
Chris Wright
2c3c8bea60 sysfs: add struct file* to bin_attr callbacks
This allows bin_attr->read,write,mmap callbacks to check file specific data
(such as inode owner) as part of any privilege validation.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
68d75ed4b8 sysfs: Remove usage of S_BIAS to avoid merge conflict with the vfs tree
In Al's latest vfs tree the code is reworked and S_BIAS has been removed.

It turns out that checking to see if a super block is in the
middle of an unmount in sysfs_exit_ns is unnecessary because we
remove the super_block from the s_supers/s_instances list before
struct sysfs_super_info pointed to by sb->s_fs_info is freed.

For now just delete the unnecessary check to see if a superblock is in the
middle of an unmount, it isn't necessary with or without Al's changes
and it just causes a needless conflict.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
27eabc7cb4 sysfs: Don't use enums in inline function declaration.
It appears gcc can't cope with using an enum that is only declared in
an inline function declaration, that doesn't even use the variable
that is so declared.

Avoid the silliness and replace the enum with an int, and make gcc
happy.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Serge E. Hallyn
b9d8b45ee3 sysfs-namespaces: add a high-level Documentation file
The first three paragraphs are almost verbatim taken from Eric's
commit message on the patch introducing network ns tags.  The next
two paragraphs I wrote to be a brief high level overview.  The last
section is taken from the commit message on "Implement sysfs tagged
directory support", but updated.  Hopefully correctly.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Serge E. Hallyn
be867b194a sysfs: Comment sysfs directory tagging logic
Add some in-line comments to explain the new infrastructure, which
was introduced to support sysfs directory tagging with namespaces.
I think an overall description someplace might be good too, but it
didn't really seem to fit into Documentation/filesystems/sysfs.txt,
which appears more geared toward users, rather than maintainers, of
sysfs.

(Tejun, please let me know if I can make anything clearer or failed
altogether to comment something that should be commented.)

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
f349cf3473 driver core: Implement ns directory support for device classes.
device_del and device_rename were modified to use
sysfs_delete_link and sysfs_rename_link respectively to ensure
when these operations happen on devices whose classes
are in namespace directories they work properly.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
746edb7ae8 sysfs: Implement sysfs_delete_link
When removing a symlink sysfs_remove_link does not provide
enough information to figure out which tagged directory the symlink
falls in.  So I need sysfs_delete_link which is passed the target
of the symlink to delete.

sysfs_rename_link is updated to call sysfs_delete_link instead
of sysfs_remove_link as we have all of the information necessary
and the callers are interesting.

Both of these functions now have enough information to find a symlink
in a tagged directory.  The only restriction is that they must be called
before the target kobject is renamed or deleted.  If they are called
later I loose track of which tag the target kobject was marked with
and can no longer find the old symlink to remove it.

This patch was split from an earlier patch.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
af10ec77b4 sysfs: Add support for tagged directories with untagged members.
I had hopped to avoid this but the bonding driver adds a file
to /sys/class/net/  and the easiest way to handle that file is
to make it untagged and to register it only once.

So relax the rules on tagged directories, and make bonding work.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
3ff195b011 sysfs: Implement sysfs tagged directory support.
The problem.  When implementing a network namespace I need to be able
to have multiple network devices with the same name.  Currently this
is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and
potentially a few other directories of the form /sys/ ... /net/*.

What this patch does is to add an additional tag field to the
sysfs dirent structure.  For directories that should show different
contents depending on the context such as /sys/class/net/, and
/sys/devices/virtual/net/ this tag field is used to specify the
context in which those directories should be visible.  Effectively
this is the same as creating multiple distinct directories with
the same name but internally to sysfs the result is nicer.

I am calling the concept of a single directory that looks like multiple
directories all at the same path in the filesystem tagged directories.

For the networking namespace the set of directories whose contents I need
to filter with tags can depend on the presence or absence of hotplug
hardware or which modules are currently loaded.  Which means I need
a simple race free way to setup those directories as tagged.

To achieve a reace free design all tagged directories are created
and managed by sysfs itself.

Users of this interface:
- define a type in the sysfs_tag_type enumeration.
- call sysfs_register_ns_types with the type and it's operations
- sysfs_exit_ns when an individual tag is no longer valid

- Implement mount_ns() which returns the ns of the calling process
  so we can attach it to a sysfs superblock.
- Implement ktype.namespace() which returns the ns of a syfs kobject.

Everything else is left up to sysfs and the driver layer.

For the network namespace mount_ns and namespace() are essentially
one line functions, and look to remain that.

Tags are currently represented a const void * pointers as that is
both generic, prevides enough information for equality comparisons,
and is trivial to create for current users, as it is just the
existing namespace pointer.

The work needed in sysfs is more extensive.  At each directory
or symlink creating I need to check if the directory it is being
created in is a tagged directory and if so generate the appropriate
tag to place on the sysfs_dirent.  Likewise at each symlink or
directory removal I need to check if the sysfs directory it is
being removed from is a tagged directory and if so figure out
which tag goes along with the name I am deleting.

Currently only directories which hold kobjects, and
symlinks are supported.  There is not enough information
in the current file attribute interfaces to give us anything
to discriminate on which makes it useless, and there are
no potential users which makes it an uninteresting problem
to solve.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
bc451f2058 kobj: Add basic infrastructure for dealing with namespaces.
Move complete knowledge of namespaces into the kobject layer
so we can use that information when reporting kobjects to
userspace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
ba514a57f5 sysfs: Remove double free sysfs_get_sb
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:31 -07:00
Eric W. Biederman
9e7fdd25b2 sysfs: Basic support for multiple super blocks
Add all of the necessary bioler plate to support
multiple superblocks in sysfs.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:30 -07:00