Commit Graph

62 Commits

Author SHA1 Message Date
Alan Stern e7b0d26a86 [PATCH] sysfs: reinstate exclusion between method calls and attribute unregistration
This patch (as869) reinstates the mutual exclusion between sysfs
attribute method calls and attribute unregistration.  The
previously-reported deadlocks have been fixed, and this exclusion is
by far the simplest way to avoid races during driver unbinding.

The check for orphaned read-buffers has been moved down slightly, so
that the remainder of a partially-read buffer will still be available
to userspace even after the attribute has been unregistered.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:29:26 -07:00
Alan Stern d9a9cdfb07 [PATCH] sysfs and driver core: add callback helper, used by SCSI and S390
This patch (as868) adds a helper routine for device drivers that need
to set up a callback to perform some action in a different process's
context.  This is intended for use by attribute methods that want to
unregister themselves or their parent device.  Attribute method calls
are mutually exclusive with unregistration, so such actions cannot be
taken directly.

Two attribute methods are converted to use the new helper routine: one
for SCSI device deletion and one for System/390 ccwgroup devices.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:29:26 -07:00
Hugh Dickins 266d4f4037 [PATCH] suspend regression: sysfs deadlock
Suspend deadlocks when trying to unregister /sys/block/sr0.

This comes from Oliver's commit 94bebf4d1b
"Driver core: fix race in sysfs between sysfs_remove_file() and
read()/write()".

sysfs_write_file downs buffer->sem while calling flush_write_buffer, and
flushing that particular write buffer entails downing buffer->sem in
orphan_all_buffers, resulting in the obvious self-deadlock.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-06 17:59:14 -08:00
Mark Lord 0de1517e23 [PATCH] Fix 2.6.21 rfcomm lockups
Any attempt to open/use a bluetooth rfcomm device locks up
scheduling completely on my machine.

Interrupts (ping, alt-sysrq) seem to be alive, but nothing else.

This was working fine in 2.6.20, broken now in 2.6.21-rc2-git*

Reverting this change (below) fixes it:

| author    Marcel Holtmann <marcel@holtmann.org>
|      Sat, 17 Feb 2007 22:58:57 +0000 (23:58 +0100)
| committer    David S. Miller <davem@sunset.davemloft.net>
|      Mon, 26 Feb 2007 19:42:41 +0000 (11:42 -0800)
| commit    c1a3313698
| tree    337a876f72    tree | snapshot
| parent    f5ffd4620a    commit | diff
| | [Bluetooth] Make use of device_move() for RFCOMM TTY devices
| | In the case of bound RFCOMM TTY devices the parent is not available
| before its usage. So when opening a RFCOMM TTY device, move it to
| the corresponding ACL device as a child. When closing the device,
| move it back to the virtual device tree.
| Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The simplest fix for this bug is to prevent sysfs_move_dir()
from self-deadlocking when (old_parent == new_parent).

This patch prevents total system lockup when using rfcomm devices.

Signed-off-by:  Mark Lord <mlord@pobox.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-06 09:30:24 -08:00
Linus Torvalds a7538a7f87 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6:
  Revert "Driver core: let request_module() send a /sys/modules/kmod/-uevent"
  Driver core: fix error by cleanup up symlinks properly
  make kernel/kmod.c:kmod_mk static
  power management: fix struct layout and docs
  power management: no valid states w/o pm_ops
  Driver core: more fallout from class_device changes for pcmcia
  sysfs: move struct sysfs_dirent to private header
  driver core: refcounting fix
  Driver core: remove class_device_rename
2007-02-26 11:41:30 -08:00
Alan Stern dfa87c824a sysfs: allow attributes to be added to groups
This patch (as860) adds two new sysfs routines:
sysfs_add_file_to_group() and sysfs_remove_file_from_group().
A later patch adds code that uses the new routines.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-23 15:03:46 -08:00
Adam J. Richter d56c3eae67 sysfs: move struct sysfs_dirent to private header
struct sysfs_dirent is private to the fs/sysfs/ subtree.  It is
not even referenced as an opaque structure outside of that subtree.

The following patch moves the declaration from include/linux/sysfs.h to
fs/sysfs/sysfs.h, making it clearer that nothing else in the kernel
dereferences it.

I have been running this patch for years.  Please integrate and forward
upstream if there are no objections.

From: "Adam J. Richter" <adam@yggdrasil.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-23 14:52:09 -08:00
Randy Dunlap f95d882d81 PCI/sysfs/kobject kernel-doc fixes
Fix kernel-doc warnings in PCI, sysfs, and kobject files.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 15:30:10 -08:00
Josef 'Jeff' Sipek ee9b6d61a2 [PATCH] Mark struct super_operations const
This patch is inspired by Arjan's "Patch series to mark struct
file_operations and struct inode_operations const".

Compile tested with gcc & sparse.

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:47 -08:00
Arjan van de Ven c5ef1c42c5 [PATCH] mark struct inode_operations const 3
Many struct inode_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00
Robert P. J. Day c376222960 [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc().
Replace appropriate pairs of "kmem_cache_alloc()" + "memset(0)" with the
corresponding "kmem_cache_zalloc()" call.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Greg KH <greg@kroah.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Jan Kara <jack@ucw.cz>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:27 -08:00
Eric W. Biederman b592fcfe7f sysfs: Shadow 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/*. 

What I want is a separate /sys/class/net directory in sysfs for each
network namespace, and I want to name each of them /sys/class/net.

I looked and the VFS actually allows that.  All that is needed is
for /sys/class/net to implement a follow link method to redirect
lookups to the real directory you want. 

Implementing a follow link method that is sensitive to the current
network namespace turns out to be 3 lines of code so it looks like a
clean approach.  Modifying sysfs so it doesn't get in my was is a bit
trickier. 

I am calling the concept of multiple directories all at the same path
in the filesystem shadow directories.  With the directory entry really
at that location the shadow master. 

The following patch modifies sysfs so it can handle a directory
structure slightly different from the kobject tree so I can implement
the shadow directories for handling /sys/class/net/.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:14 -08:00
Oliver Neukum 82244b169e sysfs: error handling in sysfs, fill_read_buffer()
if a driver returns an error in fill_read_buffer(), the buffer will be
marked as filled. Subsequent reads will return eof. But there is
no data because of an error, not because it has been read.
Not marking the buffer filled is the obvious fix.

Signed-off-by: Oliver Neukum <oliver@neukum.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:13 -08:00
Mariusz Kozlowski f750653670 sysfs: kobject_put cleanup
This patch removes redundant argument checks for kobject_put().

Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:13 -08:00
Frederik Deweerdt d3fc373ac5 sysfs: suppress lockdep warnings
Lockdep issues the following warning:
[    9.064000] =============================================
[    9.064000] [ INFO: possible recursive locking detected ]
[    9.064000] 2.6.20-rc3-mm1 #3
[    9.064000] ---------------------------------------------
[    9.064000] init/1 is trying to acquire lock:
[    9.064000]  (&sysfs_inode_imutex_key){--..}, at: [<c03e6afc>] mutex_lock+0x1c/0x1f
[    9.064000]
[    9.064000] but task is already holding lock:
[    9.064000]  (&sysfs_inode_imutex_key){--..}, at: [<c03e6afc>] mutex_lock+0x1c/0x1f
[    9.065000]
[    9.065000] other info that might help us debug this:
[    9.065000] 2 locks held by init/1:
[    9.065000]  #0:  (tty_mutex){--..}, at: [<c03e6afc>] mutex_lock+0x1c/0x1f
[    9.065000]  #1:  (&sysfs_inode_imutex_key){--..}, at: [<c03e6afc>] mutex_lock+0x1c/0x1f
[    9.065000]
[    9.065000] stack backtrace:
[    9.065000]  [<c010390d>] show_trace_log_lvl+0x1a/0x30
[    9.066000]  [<c0103935>] show_trace+0x12/0x14
[    9.066000]  [<c0103a2f>] dump_stack+0x16/0x18
[    9.066000]  [<c0138cb8>] print_deadlock_bug+0xb9/0xc3
[    9.066000]  [<c0138d17>] check_deadlock+0x55/0x5a
[    9.066000]  [<c013a953>] __lock_acquire+0x371/0xbf0
[    9.066000]  [<c013b7a9>] lock_acquire+0x69/0x83
[    9.066000]  [<c03e6b7e>] __mutex_lock_slowpath+0x75/0x2d1
[    9.066000]  [<c03e6afc>] mutex_lock+0x1c/0x1f
[    9.066000]  [<c01b249c>] sysfs_drop_dentry+0xb1/0x133
[    9.066000]  [<c01b25d1>] sysfs_hash_and_remove+0xb3/0x142
[    9.066000]  [<c01b30ed>] sysfs_remove_file+0xd/0x10
[    9.067000]  [<c02849e0>] device_remove_file+0x23/0x2e
[    9.067000]  [<c02850b2>] device_del+0x188/0x1e6
[    9.067000]  [<c028511b>] device_unregister+0xb/0x15
[    9.067000]  [<c0285318>] device_destroy+0x9c/0xa9
[    9.067000]  [<c0261431>] vcs_remove_sysfs+0x1c/0x3b
[    9.067000]  [<c0267a08>] con_close+0x5e/0x6b
[    9.067000]  [<c02598f2>] release_dev+0x4c4/0x6e5
[    9.067000]  [<c0259faa>] tty_release+0x12/0x1c
[    9.067000]  [<c0174872>] __fput+0x177/0x1a0
[    9.067000]  [<c01746f5>] fput+0x3b/0x41
[    9.068000]  [<c0172ee1>] filp_close+0x36/0x65
[    9.068000]  [<c0172f73>] sys_close+0x63/0xa4
[    9.068000]  [<c0102a96>] sysenter_past_esp+0x5f/0x99
[    9.068000]  =======================

This is due to sysfs_hash_and_remove() holding dir->d_inode->i_mutex
before calling sysfs_drop_dentry() which calls orphan_all_buffers()
which in turn takes node->i_mutex.

Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:13 -08:00
Oliver Neukum 94bebf4d1b Driver core: fix race in sysfs between sysfs_remove_file() and read()/write()
This patch prevents a race between IO and removing a file from sysfs.
It introduces a list of sysfs_buffers associated with a file at the inode.
Upon removal of a file the list is walked and the buffers marked orphaned.
IO to orphaned buffers fails with -ENODEV. The driver can safely free
associated data structures or be unloaded.

Signed-off-by: Oliver Neukum <oliver@neukum.name>
Acked-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:13 -08:00
Cornelia Huck c744aeae9d driver core: Allow device_move(dev, NULL).
If we allow NULL as the new parent in device_move(), we need to make sure
that the device is placed into the same place as it would if it was
newly registered:

- Consider the device virtual tree. In order to be able to reuse code,
  setup_parent() has been tweaked a bit.
- kobject_move() can fall back to the kset's kobject.
- sysfs_move_dir() uses the sysfs root dir as fallback.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-07 10:37:11 -08:00
Josef "Jeff" Sipek f427f5d5d6 [PATCH] sysfs: change uses of f_{dentry, vfsmnt} to use f_path
Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the sysfs
filesystem code.

Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:41 -08:00
Christoph Lameter e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Cornelia Huck 8a82472f86 driver core: Introduce device_move(): move a device to a new parent.
Provide a function device_move() to move a device to a new parent device. Add
auxilliary functions kobject_move() and sysfs_move_dir().
kobject_move() generates a new uevent of type KOBJ_MOVE, containing the
previous path (DEVPATH_OLD) in addition to the usual values. For this, a new
interface kobject_uevent_env() is created that allows to add further
environmental data to the uevent at the kobject layer.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:52:01 -08:00
Thomas Maier 035ed7a494 sysfs: sysfs_write_file() writes zero terminated data
since most of the files in sysfs are text files,
it would be nice, if the "store" function called
during sysfs_write_file() gets a zero terminated
string / data.
The current implementation seems not to ensure this.
(But only if it is the first time the zeroed buffer
page is allocated.)

So the buffer can be scanned by sscanf() easily,
for example.

This patch simply sets a \0 char behind the
data in buffer->page.

Signed-off-by: Thomas Maier <balagi@justmail.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:52:01 -08:00
Hidetoshi Seto 97a501849d sysfs: update obsolete comment in sysfs_update_file
And the obsolete comment should be updated (or totally removed).

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-18 12:49:54 -07:00
Hidetoshi Seto e42344514c sysfs: remove duplicated dput in sysfs_update_file
Following function can drops d_count twice against one reference
by lookup_one_len.

<SOURCE>
/**
 * sysfs_update_file - update the modified timestamp on an object attribute.
 * @kobj: object we're acting for.
 * @attr: attribute descriptor.
 */
int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
{
        struct dentry * dir = kobj->dentry;
        struct dentry * victim;
        int res = -ENOENT;

        mutex_lock(&dir->d_inode->i_mutex);
        victim = lookup_one_len(attr->name, dir, strlen(attr->name));
        if (!IS_ERR(victim)) {
                /* make sure dentry is really there */
                if (victim->d_inode &&
                    (victim->d_parent->d_inode == dir->d_inode)) {
                        victim->d_inode->i_mtime = CURRENT_TIME;
                        fsnotify_modify(victim);

                        /**
                         * Drop reference from initial sysfs_get_dentry().
                         */
                        dput(victim);
                        res = 0;
                } else
                        d_drop(victim);

                /**
                 * Drop the reference acquired from sysfs_get_dentry() above.
                 */
                dput(victim);
        }
        mutex_unlock(&dir->d_inode->i_mutex);

        return res;
}
</SOURCE>

PCI-hotplug (drivers/pci/hotplug/pci_hotplug_core.c) is only user of
this function. I confirmed that dentry of /sys/bus/pci/slots/XXX/*
have negative d_count value.

This patch removes unnecessary dput().

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-18 12:49:54 -07:00
Zach Brown 5c1fdf4150 [PATCH] pr_debug: sysfs: use size_t length modifier in pr_debug format arguments
sysfs: use size_t length modifier in pr_debug format arguments

Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 08:04:19 -07:00
Dave Hansen d8c76e6f45 [PATCH] r/o bind mount prepwork: inc_nlink() helper
This is mostly included for parity with dec_nlink(), where we will have some
more hooks.  This one should stay pretty darn straightforward for now.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:30 -07:00
Theodore Ts'o ba52de123d [PATCH] inode-diet: Eliminate i_blksize from the inode structure
This eliminates the i_blksize field from struct inode.  Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.

Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.

[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:18 -07:00
Randy.Dunlap 995982ca79 sysfs_remove_bin_file: no return value, dump_stack on error
Make sysfs_remove_bin_file() void.  If it detects an error,
printk the file name and call dump_stack().

sysfs_hash_and_remove() now returns an error code indicating
its success or failure so that sysfs_remove_bin_file() can
know success/failure.

Convert the only driver that checked the return value of
sysfs_remove_bin_file().

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-25 21:08:39 -07:00
Greg Kroah-Hartman ceeee1fb28 SYSFS: allow sysfs_create_link to create symlinks in the root of sysfs
This is needed to make the compatible link for /sys/block in the future.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-25 21:08:36 -07:00
Juha Yrjl eea3f8911f sysfs: Make poll behaviour consistent
When no events have been reported by sysfs_notify(), sd->s_events
was previously set to zero.  The initial value for new readers is
also zero, so poll was blocking, regardless of whether the attribute
was read by the process or not.

Make poll behave consistently by setting the initial value of
sd->s_events to non-zero.

Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-25 21:08:36 -07:00
Arjan van de Ven 232ba9dbd6 [PATCH] lockdep: annotate the sysfs i_mutex to be a separate class
sysfs has a different i_mutex lock order behavior for i_mutex than the
other filesystems; sysfs i_mutex is called in many places with subsystem
locks held.  At the same time, many of the VFS locking rules do not apply
to sysfs at all (cross directory rename for example).  To untangle this
mess (which gives false positives in lockdep), we're giving sysfs inodes
their own class for i_mutex.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-12 12:52:54 -07:00
Christoph Hellwig f5e54d6e53 [PATCH] mark address_space_operations const
Same as with already do with the file operations: keep them in .rodata and
prevents people from doing runtime patching.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28 14:59:04 -07:00
Akinobu Mita 1bfba4e8ea [PATCH] core: use list_move()
This patch converts the combination of list_del(A) and list_add(A, B) to
list_move(A, B).

Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:17 -07:00
David Howells 454e2398be [PATCH] VFS: Permit filesystem to override root dentry on mount
Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.

The filesystem is then required to manually set the superblock and root dentry
pointers.  For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).

The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.

This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing.  In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.

The patch also makes the following changes:

 (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
     pointer argument and return an integer, so most filesystems have to change
     very little.

 (*) If one of the convenience function is not used, then get_sb() should
     normally call simple_set_mnt() to instantiate the vfsmount. This will
     always return 0, and so can be tail-called from get_sb().

 (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
     dcache upon superblock destruction rather than shrink_dcache_anon().

     This is required because the superblock may now have multiple trees that
     aren't actually bound to s_root, but that still need to be cleaned up. The
     currently called functions assume that the whole tree is rooted at s_root,
     and that anonymous dentries are not the roots of trees which results in
     dentries being left unculled.

     However, with the way NFS superblock sharing are currently set to be
     implemented, these assumptions are violated: the root of the filesystem is
     simply a dummy dentry and inode (the real inode for '/' may well be
     inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
     with child trees.

     [*] Anonymous until discovered from another tree.

 (*) The documentation has been adjusted, including the additional bit of
     changing ext2_* into foo_* in the documentation.

[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
NeilBrown 4508a7a734 [PATCH] sysfs: Allow sysfs attribute files to be pollable
It works like this:
  Open the file
  Read all the contents.
  Call poll requesting POLLERR or POLLPRI (so select/exceptfds works)
  When poll returns,
     close the file and go to top of loop.
   or lseek to start of file and go back to the 'read'.

Events are signaled by an object manager calling
   sysfs_notify(kobj, dir, attr);

If the dir is non-NULL, it is used to find a subdirectory which
contains the attribute (presumably created by sysfs_create_group).

This has a cost of one int  per attribute, one wait_queuehead per kobject,
one int per open file.

The name "sysfs_notify" may be confused with the inotify
functionality.  Maybe it would be nice to support inotify for sysfs
attributes as well?

This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action
to be pollable

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-04-14 11:41:24 -07:00
Greg Kroah-Hartman 6e0dd741a8 [PATCH] sysfs: zero terminate sysfs write buffers
No one should be writing a PAGE_SIZE worth of data to a normal sysfs
file, so properly terminate the buffer.

Thanks to Al Viro for pointing out my supidity here.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-02 13:03:31 -07:00
Martin Waitz a580290c3e Documentation: fix minor kernel-doc warnings
This patch updates the comments to match the actual code.

Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-02 13:59:55 +02:00
Eric Sesterhenn 99cee0cd75 BUG_ON() Conversion in fs/sysfs/
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:18:38 +02:00
Arjan van de Ven 4b6f5d20b0 [PATCH] Make most file operations structs in fs/ const
This is a conversion to make the various file_operations structs in fs/
const.  Basically a regexp job, with a few manual fixups

The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:06 -08:00
Greg Kroah-Hartman b3229087c5 [PATCH] sysfs: fix a kobject leak in sysfs_add_link on the error path
As pointed out by Oliver Neukum.

Cc: Maneesh Soni <maneesh@in.ibm.com>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 13:42:59 -08:00
Greg Kroah-Hartman 832c57e9af [PATCH] sysfs: don't export dir symbols
These functions should only be used by the kobject core, and if any
driver tries to use them, bad things happen.  Unexport them to try to
prevent this from happening.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 13:42:59 -08:00
Maneesh Soni c516865cfb [PATCH] sysfs: fix problem with duplicate sysfs directories and files
The following patch checks for existing sysfs_dirent before
preparing new one while creating sysfs directories and files.

Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 13:42:59 -08:00
Eric Sesterhenn 58d49283b8 [PATCH] sysfs: kzalloc conversion
this converts fs/sysfs to kzalloc() usage.
compile tested with make allyesconfig

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 13:42:58 -08:00
Greg Kroah-Hartman 641e6f30a0 [PATCH] sysfs: sysfs_remove_dir() needs to invalidate the dentry
When calling sysfs_remove_dir() don't allow any further sysfs functions
to work for this kobject anymore.  This fixes a nasty USB cdc-acm oops
on disconnect.

Many thanks to Bob Copeland and Paul Fulghum for taking the time to
track this down.

Cc: Bob Copeland <email@bobcopeland.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 13:42:57 -08:00
Randy Dunlap 16f7e0fe2e [PATCH] capable/capability.h (fs/)
fs: Use <linux/capability.h> where capable() is used.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:13 -08:00
Jes Sorensen 1b1dcc1b57 [PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:24 -08:00
Steven Rostedt e80a5dea8e [PATCH] sysfs: handle failures in sysfs_make_dirent
I noticed that if sysfs_make_dirent fails to allocate the sd, then a
null will be passed to sysfs_put.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-04 16:18:09 -08:00
James Bottomley 36676bcbf9 [PATCH] Fix oops in sysfs_hash_and_remove_file()
The problem arises if an entity in sysfs is created and removed without
ever having been made completely visible.  In SCSI this is triggered by
removing a device while it's initialising.

The problem appears to be that because it was never made visible in sysfs,
the sysfs dentry has a null d_inode which oopses when a reference is made
to it.  The solution is simply to check d_inode and assume the object was
never made visible (and thus doesn't need deleting) if it's NULL.

(akpm: possibly a stopgap for 2.6.13 scsi problems.  May not be the
long-term fix)

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-26 19:37:13 -07:00
Linus Torvalds cc314eef01 Fix nasty ncpfs symlink handling bug.
This bug could cause oopses and page state corruption, because ncpfs
used the generic page-cache symlink handlign functions.  But those
functions only work if the page cache is guaranteed to be "stable", ie a
page that was installed when the symlink walk was started has to still
be installed in the page cache at the end of the walk.

We could have fixed ncpfs to not use the generic helper routines, but it
is in many ways much cleaner to instead improve on the symlink walking
helper routines so that they don't require that absolute stability.

We do this by allowing "follow_link()" to return a error-pointer as a
cookie, which is fed back to the cleanup "put_link()" routine.  This
also simplifies NFS symlink handling.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-19 18:02:56 -07:00
Maneesh Soni 9ca1eb3282 [PATCH] sysfs: fix sysfs_setattr
o sysfs_dirent's s_mode field should also be updated in sysfs_setattr(), else
  there could be inconsistency in the two fields. s_mode is used while
  ->readdir so as not to bring in the inode to cache.

Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29 13:12:49 -07:00
Maneesh Soni bc062b1b5c [PATCH] sysfs: fix sysfs_chmod_file
o sysfs_chmod_file() must update the new iattr field in sysfs_dirent else
  the mode change will not be persistent in case of inode evacuation from
  cache.

Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29 13:12:49 -07:00