Commit Graph

166 Commits

Author SHA1 Message Date
Miklos Szeredi 6497d160f6 sysfs: use check_submounts_and_drop()
Do have_submounts(), shrink_dcache_parent() and d_drop() atomically.

check_submounts_and_drop() can deal with negative dentries and
non-directories as well.

Non-directories can also be mounted on.  And just like directories we don't
want these to disappear with invalidation.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-05 16:23:53 -04:00
Greg Kroah-Hartman 37814ee0ba sysfs: dir.c: fix up odd do/while indentation
This fixes up the odd do/while after an if statement warning in dir.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-21 16:36:02 -07:00
Greg Kroah-Hartman ddfd6d074e sysfs: fix up 80 column coding style issues
This fixes up the 80 column coding style issues in the sysfs .c files.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-21 16:33:34 -07:00
Greg Kroah-Hartman 1b18dc2beb sysfs: fix up space coding style issues
This fixes up all of the space-related coding style issues for the sysfs
code.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-21 16:28:26 -07:00
Greg Kroah-Hartman ab9bf4be4d sysfs: remove trailing whitespace
This removes all trailing whitespace errors in the sysfs code.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-21 16:21:17 -07:00
Linus Torvalds fc76a258d4 Driver core patches for 3.11-rc1
Here's the big driver core merge for 3.11-rc1
 
 Lots of little things, and larger firmware subsystem updates, all
 described in the shortlog.  Nice thing here is that we finally get rid
 of CONFIG_HOTPLUG, after 10+ years, thanks to Stephen Rohtwell (it had
 been always on for a number of kernel releases, now it's just removed.)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the big driver core merge for 3.11-rc1

  Lots of little things, and larger firmware subsystem updates, all
  described in the shortlog.  Nice thing here is that we finally get rid
  of CONFIG_HOTPLUG, after 10+ years, thanks to Stephen Rohtwell (it had
  been always on for a number of kernel releases, now it's just
  removed)"

* tag 'driver-core-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (27 commits)
  driver core: device.h: fix doc compilation warnings
  firmware loader: fix another compile warning with PM_SLEEP unset
  build some drivers only when compile-testing
  firmware loader: fix compile warning with PM_SLEEP set
  kobject: sanitize argument for format string
  sysfs_notify is only possible on file attributes
  firmware loader: simplify holding module for request_firmware
  firmware loader: don't export cache_firmware and uncache_firmware
  drivers/base: Use attribute groups to create sysfs memory files
  firmware loader: fix compile warning
  firmware loader: fix build failure with !CONFIG_FW_LOADER_USER_HELPER
  Documentation: Updated broken link in HOWTO
  Finally eradicate CONFIG_HOTPLUG
  driver core: firmware loader: kill FW_ACTION_NOHOTPLUG requests before suspend
  driver core: firmware loader: don't cache FW_ACTION_NOHOTPLUG firmware
  Documentation: Tidy up some drivers/base/core.c kerneldoc content.
  platform_device: use a macro instead of platform_driver_register
  firmware: move EXPORT_SYMBOL annotations
  firmware: Avoid deadlock of usermodehelper lock at shutdown
  dell_rbu: Select CONFIG_FW_LOADER_USER_HELPER explicitly
  ...
2013-07-02 11:44:19 -07:00
Al Viro d55fea8ddb [readdir] convert sysfs
get rid of the kludges in sysfs_readdir()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:56:36 +04:00
Warner Wang 434749108c sysfs: sysfs_link_sibling(): fix typo in comment
Fix a typo subling->sibling in the comment of sysfs_link_sibling().

Signed-off-by: Warner Wang <warner.wang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-17 10:26:08 -07:00
Ming Lei bb2b0051d7 sysfs: check if one entry has been removed before freeing
It might be a kernel disaster if one sysfs entry is freed but
still referenced by sysfs tree.

Recently Dave and Sasha reported one use-after-free problem on
sysfs entry, and the problem has been troubleshooted with help
of debug message added in this patch.

Given sysfs_get_dirent/sysfs_put are exported APIs, even inside
sysfs they are called in many contexts(kobject/attribe add/delete,
inode init/drop, dentry lookup/release, readdir, ...), it is healthful
to check the removed flag before freeing one entry and dump message
if it is freeing without being removed first.

Cc: Dave Jones <davej@redhat.com>
Cc: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-05 15:35:52 -07:00
Ming Lei f7db5e7660 sysfs: fix use after free in case of concurrent read/write and readdir
The inode->i_mutex isn't hold when updating filp->f_pos
in read()/write(), so the filp->f_pos might be read as
0 or 1 in readdir() when there is concurrent read()/write()
on this same file, then may cause use after free in readdir().

The bug can be reproduced with Li Zefan's test code on the
link:

	https://patchwork.kernel.org/patch/2160771/

This patch fixes the use after free under this situation.

Cc: stable <stable@vger.kernel.org>
Reported-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-03 11:09:02 -07:00
Greg Kroah-Hartman 0f8b1a0204 Merge v3.9-rc5 into driver-core-next
We want the fixes in here.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-01 11:05:59 -07:00
Maarten Lankhorst 3db3c62584 sysfs: use atomic_inc_unless_negative in sysfs_get_active
It seems that sysfs has an interesting way of doing the same thing.
This removes the cpu_relax unfortunately, but if it's really needed,
it would be better to add this to include/linux/atomic.h to benefit
all atomic ops users.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25 10:42:36 -07:00
Ming Lei e5110f411d sysfs: handle failure path correctly for readdir()
In case of 'if (filp->f_pos ==  0 or 1)' of sysfs_readdir(),
the failure from filldir() isn't handled, and the reference counter
of the sysfs_dirent object pointed by filp->private_data will be
released without clearing filp->private_data, so use after free
bug will be triggered later.

This patch returns immeadiately under the situation for fixing the bug,
and it is reasonable to return from readdir() when filldir() fails.

Reported-by: Dave Jones <davej@redhat.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-20 16:53:42 -07:00
Ming Lei 991f76f837 sysfs: fix race between readdir and lseek
While readdir() is running, lseek() may set filp->f_pos as zero,
then may leave filp->private_data pointing to one sysfs_dirent
object without holding its reference counter, so the sysfs_dirent
object may be used after free in next readdir().

This patch holds inode->i_mutex to avoid the problem since
the lock is always held in readdir path.

Reported-by: Dave Jones <davej@redhat.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-20 16:53:42 -07:00
Geert Uytterhoeven 66081a7251 sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead of strcat()
The warning check for duplicate sysfs entries can cause a buffer overflow
when printing the warning, as strcat() doesn't check buffer sizes.
Use strlcat() instead.

Since strlcat() doesn't return a pointer to the passed buffer, unlike
strcat(), I had to convert the nested concatenation in sysfs_add_one() to
an admittedly more obscure comma operator construct, to avoid emitting code
for the concatenation if CONFIG_BUG is disabled.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 15:57:14 -07:00
Linus Torvalds fa93669a19 Driver core merge for 3.6-rc1
Here's the big driver core pull request for 3.6-rc1.
 
 Unlike 3.5, this kernel should be a lot tamer, with the printk changes now
 settled down.  All we have here is some extcon driver updates, w1 driver
 updates, a few printk cleanups that weren't needed for 3.5, but are good to
 have now, and some other minor fixes/changes in the driver core.
 
 All of these have been in the linux-next releases for a while now.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core changes from Greg Kroah-Hartman:
 "Here's the big driver core pull request for 3.6-rc1.

  Unlike 3.5, this kernel should be a lot tamer, with the printk changes
  now settled down.  All we have here is some extcon driver updates, w1
  driver updates, a few printk cleanups that weren't needed for 3.5, but
  are good to have now, and some other minor fixes/changes in the driver
  core.

  All of these have been in the linux-next releases for a while now.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (38 commits)
  printk: Export struct log size and member offsets through vmcoreinfo
  Drivers: hv: Change the hex constant to a decimal constant
  driver core: don't trigger uevent after failure
  extcon: MAX77693: Add extcon-max77693 driver to support Maxim MAX77693 MUIC device
  sysfs: fail dentry revalidation after namespace change fix
  sysfs: fail dentry revalidation after namespace change
  extcon: spelling of detach in function doc
  extcon: arizona: Stop microphone detection if we give up on it
  extcon: arizona: Update cable reporting calls and split headset
  PM / Runtime: Do not increment device usage counts before probing
  kmsg - do not flush partial lines when the console is busy
  kmsg - export "continuation record" flag to /dev/kmsg
  kmsg - avoid warning for CONFIG_PRINTK=n compilations
  kmsg - properly print over-long continuation lines
  driver-core: Use kobj_to_dev instead of re-implementing it
  driver-core: Move kobj_to_dev from genhd.h to device.h
  driver core: Move deferred devices to the end of dpm_list before probing
  driver core: move uevent call to driver_register
  driver core: fix shutdown races with probe/remove(v3)
  Extcon: Arizona: Add driver for Wolfson Arizona class devices
  ...
2012-07-26 11:25:33 -07:00
Andrew Morton 17f79be93d sysfs: fail dentry revalidation after namespace change fix
don't assume that KOBJ_NS_TYPE_NONE==0.  Also save a test-n-branch.

Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17 09:43:55 -07:00
Glauber Costa e5bcac6147 sysfs: fail dentry revalidation after namespace change
When we change the namespace tag of a sysfs entry, the associated dentry
is still kept around. readdir() will work correctly and not display the
old entries, but open() will still succeed, so will reads and writes.

This will no longer happen if sysfs is remounted, hinting that this is a
cache-related problem.

I am using the following sequence to demonstrate that:

shell1:
ip link add type veth
unshare -nm

shell2:
ip link set veth1 <pid_of_shell_1>
cat /sys/devices/virtual/net/veth1/ifindex

Before that patch, this will succeed (fail to fail). After it, it will
correctly return an error. Differently from a normal rename, which we
handle fine, changing the object namespace will keep it's path intact.
So this check seems necessary as well.

[ v2: get type from parent, as suggested by Eric Biederman ]

Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: Tejun Heo <tj@kernel.org>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-17 09:43:55 -07:00
Al Viro e77fb7cef8 sysfs: just use d_materialise_unique()
same as for nfs et.al.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:35:12 +04:00
Al Viro 469796d105 sysfs: switch to ->s_d_op and ->d_release()
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 <viro@zeniv.linux.org.uk>
2012-07-14 16:35:06 +04:00
Al Viro 00cd8dd3bf stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:32 +04:00
Al Viro 0b728e1911 stop passing nameidata * to ->d_revalidate()
Just the lookup flags.  Die, bastard, die...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:14 +04:00
Alan Stern 356c05d58a sysfs: get rid of some lockdep false positives
This patch (as1554) fixes a lockdep false-positive report.  The
problem arises because lockdep is unable to deal with the
tree-structured locks created by the device core and sysfs.

This particular problem involves a sysfs attribute method that
unregisters itself, not from the device it was called for, but from a
descendant device.  Lockdep doesn't understand the distinction and
reports a possible deadlock, even though the operation is safe.

This is the sort of thing that would normally be handled by using a
nested lock annotation; unfortunately it's not feasible to do that
here.  There's no sensible way to tell sysfs when attribute removal
occurs in the context of a parent attribute method.

As a workaround, the patch adds a new flag to struct attribute
telling sysfs not to inform lockdep when it acquires a readlock on a
sysfs_dirent instance for the attribute.  The readlock is still
acquired, but lockdep doesn't know about it and hence does not
complain about impossible deadlock scenarios.

Also added are macros for static initialization of attribute
structures with the ignore_lockdep flag set.  The three offending
attributes in the USB subsystem are converted to use the new macros.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Tejun Heo <tj@kernel.org>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-14 12:19:56 -07:00
Sasikantha babu b4eafca113 sysfs: Removed dup_name entirely in sysfs_rename
Since no one using "dup_name", removed it completely in sysfs_rename.

Signed-off-by: Sasikantha babu <sasikanth.v19@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-02 14:55:09 -07:00
Dan Williams 3a198886ab sysfs: handle 'parent deleted before child added'
In scsi at least two cases of the parent device being deleted before the
child is added have been observed.

1/ scsi is performing async scans and the device is removed prior to the
   async can thread running (can happen with an in-opportune / unlikely
   unplug during initial scan).

2/ libsas discovery event running after the parent port has been torn
   down (this is a bug in libsas).

Result in crash signatures like:
 BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
 IP: [<ffffffff8115e100>] sysfs_create_dir+0x32/0xb6
 ...
 Process scsi_scan_8 (pid: 5417, threadinfo ffff88080bd16000, task ffff880801b8a0b0)
 Stack:
  00000000fffffffe ffff880813470628 ffff88080bd17cd0 ffff88080614b7e8
  ffff88080b45c108 00000000fffffffe ffff88080bd17d20 ffffffff8125e4a8
  ffff88080bd17cf0 ffffffff81075149 ffff88080bd17d30 ffff88080614b7e8
 Call Trace:
  [<ffffffff8125e4a8>] kobject_add_internal+0x120/0x1e3
  [<ffffffff81075149>] ? trace_hardirqs_on+0xd/0xf
  [<ffffffff8125e641>] kobject_add_varg+0x41/0x50
  [<ffffffff8125e70b>] kobject_add+0x64/0x66
  [<ffffffff8131122b>] device_add+0x12d/0x63a

In this scenario the parent is still valid (because we have a
reference), but it has been device_del()'d which means its kobj->sd
pointer is NULL'd via:

 device_del()->kobject_del()->sysfs_remove_dir()

...and then sysfs_create_dir() (without this fix) goes ahead and
de-references parent_sd via sysfs_ns_type():

 return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT;

This scenario is being fixed in scsi/libsas, but if other subsystems
present the same ordering the system need not immediately crash.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: James Bottomley <JBottomley@parallels.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-10 14:48:51 -07:00
Tom Goff 70fa4a62e9 sysfs: Update the name hash for an entry after changing the namespace
This is needed to allow renaming network devices that have been moved
to another network namespace.

Signed-off-by: Tom Goff <thomas.goff@boeing.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-09 15:33:00 -07:00
Greg Kroah-Hartman 54d20f006c Revert "sysfs: Kill nlink counting."
This reverts commit 524b6c5b39.

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

Reported-by: Jiri Slaby <jslaby@suse.cz>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 13:03:10 -08:00
Eric W. Biederman d5c38b137a sysfs: Update the name hash when renaming sysfs entries
This fixes a bug introduced with sysfs name hashes where renaming a
network device appears to succeed but silently makes the sysfs files for
that network device inaccessible.

In at least one configuration this bug has stopped networking from
coming up during boot.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-31 11:30:48 -08:00
Eric W. Biederman 524b6c5b39 sysfs: Kill nlink counting.
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 <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:41:46 -08:00
Eric W. Biederman cafa6b5dd7 sysfs: Store the sysfs inode in an unsigned int.
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 <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:41:46 -08:00
Eric W. Biederman 4e4d6d860b sysfs: Add s_hash to sysfs_dirent and order directory entries by hash
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 <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 12:36:17 -08:00
Eric W. Biederman f6d90b4f9c sysfs: Make sysfs_rename safe with sysfs_dirents in rbtrees.
In sysfs_rename we need to remove the optimization of not calling
sysfs_unlink_sibling and sysfs_link_sibling if the renamed parent
directory is not changing.  This optimization is no longer valid now
that sysfs dirents are stored in an rbtree sorted by name.

Move the assignment of s_ns before the call of sysfs_link_sibling.  With
no sysfs_dirent fields changing after the call of sysfs_link_sibling
this allows sysfs_link_sibling to take any of the directory entries into
account when it builds the rbtrees, and s_ns looks like a prime canidate
to be used in the rbtree in the future.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Greg KH <gregkh@suse.de>
Cc: David Miller <davem@davemloft.net>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-01 09:16:14 -07:00
Eric W. Biederman b9e2780d57 sysfs: Remove support for tagged directories with untagged members (again)
In commit 8a9ea3237e ("Merge git://.../davem/net-next") where my sysfs
changes from the net tree merged with the sysfs rbtree changes from
Mickulas Patocka the conflict resolution failed to preserve the
simplified property that was the point of my changes.

That is sysfs_find_dirent can now say something is a match if and only
s_name and s_ns match what we are looking for, and sysfs_readdir can
simply return all of the directory entries where s_ns matches the
directory that we should be returning.

Now that we are back to exact matches we can tweak sysfs_find_dirent and
the name rb_tree to order sysfs_dirents by s_ns s_name and remove the
second loop in sysfs_find_dirent.  However that change seems a bit much
for a conflict resolution so it can come later.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-25 15:10:28 +02:00
Linus Torvalds 8a9ea3237e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1745 commits)
  dp83640: free packet queues on remove
  dp83640: use proper function to free transmit time stamping packets
  ipv6: Do not use routes from locally generated RAs
  |PATCH net-next] tg3: add tx_dropped counter
  be2net: don't create multiple RX/TX rings in multi channel mode
  be2net: don't create multiple TXQs in BE2
  be2net: refactor VF setup/teardown code into be_vf_setup/clear()
  be2net: add vlan/rx-mode/flow-control config to be_setup()
  net_sched: cls_flow: use skb_header_pointer()
  ipv4: avoid useless call of the function check_peer_pmtu
  TCP: remove TCP_DEBUG
  net: Fix driver name for mdio-gpio.c
  ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAIT
  rtnetlink: Add missing manual netlink notification in dev_change_net_namespaces
  ipv4: fix ipsec forward performance regression
  jme: fix irq storm after suspend/resume
  route: fix ICMP redirect validation
  net: hold sock reference while processing tx timestamps
  tcp: md5: add more const attributes
  Add ethtool -g support to virtio_net
  ...

Fix up conflicts in:
 - drivers/net/Kconfig:
	The split-up generated a trivial conflict with removal of a
	stale reference to Documentation/networking/net-modules.txt.
	Remove it from the new location instead.
 - fs/sysfs/dir.c:
	Fairly nasty conflicts with the sysfs rb-tree usage, conflicting
	with Eric Biederman's changes for tagged directories.
2011-10-25 13:25:22 +02:00
Eric W. Biederman 903e21e2ee sysfs: Reject with a warning invalid uses of tagged directories.
sysfs is a core piece of ifrastructure that many people use and
few people have all of the rules in their head on how to use
it correctly.  Add warnings for people using tagged directories
improperly to that any misuses can be caught and diagnosed quickly.

A single inexpensive test in sysfs_find_dirent is almost sufficient
to catch all possible misuses.  An additional warning is needed
in sysfs_add_dirent so that we actually fail when attempting to
add an untagged dirent in a tagged directory.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-19 19:24:16 -04:00
Eric W. Biederman 23396180a9 sysfs: Remove support for tagged directories with untagged members.
Now that /sys/class/net/bonding_masters is implemented as a tagged sysfs
file we can remove support for untagged files in tagged directories.

This change removes any ambiguity of what a NULL namespace value
means.  A NULL namespace parameter after this patch means
that we are talking about an untagged sysfs dirent.

This makes the sysfs code much less prone to mistakes when during
maintenance.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-19 19:24:15 -04:00
Heiko Carstens c4253cb074 sysfs: add unsigned long cast to prevent compile warning
"sysfs: use rb-tree for inode number lookup" added a new printk which
causes a new compile warning on s390 (and few other architectures):

fs/sysfs/dir.c: In function 'sysfs_link_sibling':
fs/sysfs/dir.c:63:4: warning: format '%lx' expects argument of type
  'long unsigned int', but argument 2 has type 'ino_t' [-Wform

Add an explicit unsigned long cast since ino_t is an unsigned long on
most architectures.

Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-26 16:21:15 -07:00
Mikulas Patocka a406f75840 sysfs: use rb-tree for inode number lookup
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 <mpatocka@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 17:43:53 -07:00
Mikulas Patocka 58f2a4c793 sysfs: remove s_sibling hacks
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 <mpatocka@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 17:43:52 -07:00
Mikulas Patocka 4f72c0cab4 sysfs: use rb-tree for name lookups
sysfs: use rb-tree for name lookups

Use red-black tree for name lookups.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 17:43:52 -07:00
Mikulas Patocka 7f9838fd01 sysfs: count subdirectories
sysfs: count subdirectories

This patch introduces a subdirectory counter for each sysfs directory.

Without the patch, sysfs_refresh_inode would walk all entries of the directory
to calculate the number of subdirectories.

This patch improves time of "ls -la /sys/block" when there are 10000 block
devices from 9 seconds to 0.19 seconds.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 17:43:30 -07:00
Nick Piggin 34286d6662 fs: rcu-walk aware d_revalidate method
Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin fb045adb99 fs: dcache reduce branches in lookup path
Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:28 +11:00
Nick Piggin fe15ce446b fs: change d_delete semantics
Change d_delete from a dentry deletion notification to a dentry caching
advise, more like ->drop_inode. Require it to be constant and idempotent,
and not take d_lock. This is how all existing filesystems use the callback
anyway.

This makes fine grained dentry locking of dput and dentry lru scanning
much simpler.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:18 +11:00
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 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 fac2622bba sysfs: Pass super_block to sysfs_get_inode
Currently sysfs_get_inode magically returns an inode on
sysfs_sb.  Make the super_block parameter explicit and
the code becomes clearer.

Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-07 17:04:52 -08:00
Eric W. Biederman a2db684287 sysfs: Only take active references on attributes.
If we exclude directories and symlinks from the set of sysfs
dirents where we need active references we are left with
sysfs attributes (binary or not).

- Tweak sysfs_deactivate to only do something on attributes
- Move lockdep initialization into sysfs_file_add_mode to
  limit it to just attributes.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-07 17:04:51 -08:00
Eric W. Biederman e72ceb8cca sysfs: Remove sysfs_get/put_active_two
It turns out that holding an active reference on a directory is
pointless.  The purpose of the active references are to allows us to
block when removing sysfs entries that have custom methods so we don't
remove modules while running modular code and to keep those custom
methods from accessing data structures after the files have been
removed.  Further sysfs_remove_dir remove all elements in the
directory before removing the directory itself, so there is no chance
we will remove a directory with active children.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-07 17:04:51 -08:00