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* userns: Restrict when proc and sysfs can be mountedEric W. Biederman2013-03-271-0/+4
| | | | | | | | | | | | | | | | | | | | | | Only allow unprivileged mounts of proc and sysfs if they are already mounted when the user namespace is created. proc and sysfs are interesting because they have content that is per namespace, and so fresh mounts are needed when new namespaces are created while at the same time proc and sysfs have content that is shared between every instance. Respect the policy of who may see the shared content of proc and sysfs by only allowing new mounts if there was an existing mount at the time the user namespace was created. In practice there are only two interesting cases: proc and sysfs are mounted at their usual places, proc and sysfs are not mounted at all (some form of mount namespace jail). Cc: stable@vger.kernel.org Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* sysfs: Fixed a trailing white space errorBin Wang2013-01-171-1/+1
| | | | | | | This patch removes the trailing white space in fs/sysfs/mount.c. Signed-off-by: Bin Wang <wbin00@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* userns: Allow unprivilged mounts of proc and sysfsEric W. Biederman2012-11-201-0/+1
| | | | | | | | | - The context in which proc and sysfs are mounted have no effect on the the uid/gid of their files so no conversion is needed except allowing the mount. Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* VFS: Pass mount flags to sget()David Howells2012-07-141-2/+1
| | | | | | | | | Pass mount flags to sget() so that it can use them in initialising a new superblock before the set function is called. They could also be passed to the compare function. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* sysfs: switch to ->s_d_op and ->d_release()Al Viro2012-07-141-0/+1
| | | | | | | | | 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>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-03-211-2/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "This is _not_ all; in particular, Miklos' and Jan's stuff is not there yet." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits) ext4: initialization of ext4_li_mtx needs to be done earlier debugfs-related mode_t whack-a-mole hfsplus: add an ioctl to bless files hfsplus: change finder_info to u32 hfsplus: initialise userflags qnx4: new helper - try_extent() qnx4: get rid of qnx4_bread/qnx4_getblk take removal of PF_FORKNOEXEC to flush_old_exec() trim includes in inode.c um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it um: embed ->stub_pages[] into mmu_context gadgetfs: list_for_each_safe() misuse ocfs2: fix leaks on failure exits in module_init ecryptfs: make register_filesystem() the last potential failure exit ntfs: forgets to unregister sysctls on register_filesystem() failure logfs: missing cleanup on register_filesystem() failure jfs: mising cleanup on register_filesystem() failure make configfs_pin_fs() return root dentry on success configfs: configfs_create_dir() has parent dentry in dentry->d_parent configfs: sanitize configfs_create() ...
| * switch open-coded instances of d_make_root() to new helperAl Viro2012-03-211-2/+1
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | sysfs: change permissions for /sys from 0755 to 0555Vitaly Kuznetsov2012-01-251-1/+1
|/ | | | | | | | There is a misleading difference between /proc and /sys permissions, /proc is 0555 and /sys is 0755. But as it is impossible to create or unlink something in /sys it would be nice to have same permissions. Signed-off-by: Vitaly Kuznetsov <vitty@altlinux.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Delay struct net freeing while there's a sysfs instance refering to itAl Viro2011-06-121-26/+11
| | | | | | | | | | | | | | | | | | | | | | * new refcount in struct net, controlling actual freeing of the memory * new method in kobj_ns_type_operations (->drop_ns()) * ->current_ns() semantics change - it's supposed to be followed by corresponding ->drop_ns(). For struct net in case of CONFIG_NET_NS it bumps the new refcount; net_drop_ns() decrements it and calls net_free() if the last reference has been dropped. Method renamed to ->grab_current_ns(). * old net_free() callers call net_drop_ns() instead. * sysfs_exit_ns() is gone, along with a large part of callchain leading to it; now that the references stored in ->ns[...] stay valid we do not need to hunt them down and replace them with NULL. That fixes problems in sysfs_lookup() and sysfs_readdir(), along with getting rid of sb->s_instances abuse. Note that struct net *shutdown* logics has not changed - net_cleanup() is called exactly when it used to be called. The only thing postponed by having a sysfs instance refering to that struct net is actual freeing of memory occupied by struct net. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* convert sysfsAl Viro2010-10-291-19/+13
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch sysfs to ->evict_inode()Al Viro2010-08-091-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* sysfs: Remove usage of S_BIAS to avoid merge conflict with the vfs treeEric W. Biederman2010-05-211-3/+8
| | | | | | | | | | | | | | | | | | | 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>
* sysfs: Implement sysfs tagged directory support.Eric W. Biederman2010-05-211-1/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* sysfs: Remove double free sysfs_get_sbEric W. Biederman2010-05-211-1/+0
| | | | | | Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Basic support for multiple super blocksEric W. Biederman2010-05-211-2/+56
| | | | | | | | | | 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>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* sysfs: Kill unused sysfs_sb variable.Eric W. Biederman2010-03-081-2/+0
| | | | | | | | | | | Now that there are no more users we can remove the sysfs_sb variable. 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>
* sysfs: Pass super_block to sysfs_get_inodeEric W. Biederman2010-03-081-1/+1
| | | | | | | | | | | | 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>
* sysfs: reference sysfs_dirent from sysfs inodesEric W. Biederman2009-03-251-0/+1
| | | | | | | | | | | | | | | The sysfs_dirent serves as both an inode and a directory entry for sysfs. To prevent the sysfs inode numbers from being freed prematurely hold a reference to sysfs_dirent from the sysfs inode. [akpm@linux-foundation.org: add comment] Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Cc: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Take sysfs_mutex when fetching the root inode.Eric W. Biederman2009-03-251-0/+2
| | | | | | | | | | | | | | sysfs_get_inode ultimately calls sysfs_count_nlink when the a directory inode is fectched. sysfs_count_nlink needs to be called under the sysfs_mutex to guard against the unlikely but possible scenario that the root directory is changing as we are counting the number entries in it, and just in general to be consistent. Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* SYSFS: use standard magic.h for sysfsQinghuang Feng2009-03-251-2/+1
| | | | | | | | | SYSFS_MAGIC has been added into magic.h, so only use that definition in magic.h to avoid potential consistency problem. Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Support sysfs_notify from atomic context with new sysfs_notify_direntNeil Brown2008-10-161-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* fs: replace remaining __FUNCTION__ occurrencesHarvey Harrison2008-04-301-1/+1
| | | | | | | | __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: bdi init hooksPeter Zijlstra2007-10-171-0/+4
| | | | | | | | | provide BDI constructor/destructor hooks [akpm@linux-foundation.org: compile fix] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysfs: add copyrightsTejun Heo2007-10-121-1/+9
| | | | | | | | | Sysfs has gone through considerable amount of reimplementation. Add copyrights. Any objections? :-) Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: make sysfs_root a regular directory direntTejun Heo2007-10-121-1/+2
| | | | | | | | | | | | sysfs_root is different from a regular directory dirent in that it's of type SYSFS_ROOT and doesn't have a name. These differences aren't used by anybody and only adds to complexity. Make sysfs_root a regular directory dirent. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Remove s_dentryEric W. Biederman2007-10-121-1/+0
| | | | | | | | | | | | | The only uses of s_dentry left are the code that maintains s_dentry and trivial users that don't actually need it. So this patch removes the s_dentry maintenance code and restructures the trivial uses to use something else. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Make sysfs_mount staticEric W. Biederman2007-10-121-1/+1
| | | | | | | | | | | | | | | This patch modifies the users of sysfs_mount to use sysfs_root instead (which is what they are looking for). It then makes sysfs_mount static to keep people from using it by accident. The net result is slightly faster and cleaner code. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Use kill_anon_superEric W. Biederman2007-10-121-1/+1
| | | | | | | | | | | | | | | Since sysfs no longer stores fs directory information in the dcache on a permanent basis kill_litter_super it is inappropriate and actively wrong. It will decrement the count on all dentries left in the dcache before trying to free them. At the moment this is not biting us only because we never unmount sysfs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Move all of inode initialization into sysfs_init_inodeEric W. Biederman2007-10-121-5/+0
| | | | | | | | Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Remove first pass at shadow directory supportEric W. Biederman2007-10-121-1/+1
| | | | | | | | | | | | | | | | | | | While shadow directories appear to be a good idea, the current scheme of controlling their creation and destruction outside of sysfs appears to be a locking and maintenance nightmare in the face of sysfs directories dynamically coming and going. Which can now occur for directories containing network devices when CONFIG_SYSFS_DEPRECATED is not set. This patch removes everything from the initial shadow directory support that allowed the shadow directory creation to be controlled at a higher level. So except for a few bits of sysfs_rename_dir everything from commit b592fcfe7f06c15ec11774b5be7ce0de3aa86e73 is now gone. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: cleanup semaphore.hDave Young2007-10-121-1/+0
| | | | | | | | | Cleanup semaphore.h Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* mm: Remove slab destructors from kmem_cache_create().Paul Mundt2007-07-201-1/+1
| | | | | | | | | | | | | | Slab destructors were no longer supported after Christoph's c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been BUGs for both slab and slub, and slob never supported them either. This rips out support for the dtor pointer from kmem_cache_create() completely and fixes up every single callsite in the kernel (there were about 224, not including the slab allocator definitions themselves, or the documentation references). Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* sysfs: fix sysfs root inode nlink accountingTejun Heo2007-07-191-5/+5
| | | | | | | | | | | | | | | While making sysfs indoes hashed, sysfs root inode was left out. Now that nlink accounting depends on the inode being on the hash, sysfs root inode nlink isn't adjusted properly. Put sysfs root inode on the inode hash by allocating it using sysfs_get_inode() like other sysfs inodes. While at it, massage comments a bit. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: make directory dentries and inodes reclaimableTejun Heo2007-07-121-1/+1
| | | | | | | | | | | | | | | | | | | | | This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: rename sysfs_dirent->s_type to s_flags and make room for flagsTejun Heo2007-07-121-1/+1
| | | | | | | | | | | | Rename sysfs_dirent->s_type to s_flags, pack type into lower eight bits and reserve the rest for flags. sysfs_type() can used to access the type. All existing sd->s_type accesses are converted to use sysfs_type(). While at it, type test is changed to equality test instead of bit-and test where appropriate. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: use singly-linked list for sysfs_dirent treeTejun Heo2007-07-121-3/+0
| | | | | | | | | | | | | | Make sysfs_dirent use singly linked list for its tree structure. sysfs_link_sibling() and sysfs_unlink_sibling() functions are added to handle simpler cases. It adds some complexity and cpu cycle overhead but reduced memory footprint is worthwhile on big machines. This change reduces the sizeof sysfs_dirent from 104 to 88 on 64bit and from 60 to 52 on 32bit. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: fix root sysfs_dirent -> root dentry associationTejun Heo2007-07-121-0/+1
| | | | | | | | The root sysfs_dirent didn't point to the root dentry fix it. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: reorganize sysfs_new_indoe() and sysfs_create()Tejun Heo2007-07-121-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | Reorganize/clean up sysfs_new_inode() and sysfs_create(). * sysfs_init_inode() is separated out from sysfs_new_inode() and is responsible for basic initialization. * sysfs_instantiate() replaces the last step of sysfs_create() and is responsible for dentry instantitaion. * type-specific initialization is moved out to the callers. * mode is specified only once when creating a sysfs_dirent. * spurious list_del_init(&sd->s_sibling) dropped from create_dir() This change is to * prepare for inode allocation fix. * separate alloc and init code for synchronization update. * make dentry/inode initialization more flexible for later changes. This patch doesn't introduce visible behavior change. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: kill attribute file orphaningTejun Heo2007-07-121-8/+0
| | | | | | | | | | | Now that sysfs_dirent can be disconnected from kobject on deletion, there is no need to orphan each attribute files. All [bin_]attribute nodes are automatically orphaned when the parent node is deleted. Kill attribute file orphaning. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: make sysfs_dirent->s_element a unionTejun Heo2007-07-121-1/+0
| | | | | | | | | | | | | | | | | | | | | Make sd->s_element a union of sysfs_elem_{dir|symlink|attr|bin_attr} and rename it to s_elem. This is to achieve... * some level of type checking : changing symlink to point to sysfs_dirent instead of kobject is much safer and less painful now. * easier / standardized dereferencing * allow sysfs_elem_* to contain more than one entry Where possible, pointer is obtained by directly deferencing from sd instead of going through other entities. This reduces dependencies to dentry, inode and kobject. to_attr() and to_bin_attr() are unused now and removed. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: add sysfs_dirent->s_parentTejun Heo2007-07-121-0/+1
| | | | | | | | | | | | | | | | | | | | | Add sysfs_dirent->s_parent. With this patch, each sd points to and holds a reference to its parent. This allows walking sysfs tree without referencing sd->s_dentry which can go away anytime if the user doesn't control when it's deleted. sd->s_parent is initialized and parent is referenced in sysfs_attach_dirent(). Reference to parent is released when the sd is released, so as long as reference to a sd is held, s_parent can be followed. dentry walk in sysfs_readdir() is convereted to s_parent walk. This will be used to reimplement symlink such that it uses only sysfs_dirent tree. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: store sysfs inode nrs in s_ino to avoid readdir oopsesEric Sandeen2007-06-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | Backport of ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22-rc1/2.6.22-rc1-mm1/broken-out/gregkh-driver-sysfs-allocate-inode-number-using-ida.patch For regular files in sysfs, sysfs_readdir wants to traverse sysfs_dirent->s_dentry->d_inode->i_ino to get to the inode number. But, the dentry can be reclaimed under memory pressure, and there is no synchronization with readdir. This patch follows Tejun's scheme of allocating and storing an inode number in the new s_ino member of a sysfs_dirent, when dirents are created, and retrieving it from there for readdir, so that the pointer chain doesn't have to be traversed. Tejun's upstream patch uses a new-ish "ida" allocator which brings along some extra complexity; this -stable patch has a brain-dead incrementing counter which does not guarantee uniqueness, but because sysfs doesn't hash inodes as iunique expects, uniqueness wasn't guaranteed today anyway. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] Mark struct super_operations constJosef 'Jeff' Sipek2007-02-121-1/+1
| | | | | | | | | | | 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>
* sysfs: Shadow directory supportEric W. Biederman2007-02-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Driver core: fix race in sysfs between sysfs_remove_file() and read()/write()Oliver Neukum2007-02-071-0/+9
| | | | | | | | | | | | | | 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>
* [PATCH] slab: remove kmem_cache_tChristoph Lameter2006-12-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] r/o bind mount prepwork: inc_nlink() helperDave Hansen2006-10-011-1/+1
| | | | | | | | | | | 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>
* [PATCH] VFS: Permit filesystem to override root dentry on mountDavid Howells2006-06-231-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] sysfs-iattr: set inode attributesManeesh Soni2005-06-211-1/+3
| | | | | | | | | o Following patch sets the attributes for newly allocated inodes for sysfs objects. If the object has non-default attributes, inode attributes are set as saved in sysfs_dirent->s_iattr, pointer to struct iattr. Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>