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path: root/fs/fuse/dir.c
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* don't pass nameidata to ->create()Al Viro2012-07-14
| | | | | | | | boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* stop passing nameidata to ->lookup()Al Viro2012-07-14
| | | | | | | | | 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>
* stop passing nameidata * to ->d_revalidate()Al Viro2012-07-14
| | | | | | Just the lookup flags. Die, bastard, die... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* make finish_no_open() return intAl Viro2012-07-14
| | | | | | | namely, 1 ;-) That's what we want to return from ->atomic_open() instances after finish_no_open(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* kill struct opendataAl Viro2012-07-14
| | | | | | | | | Just pass struct file *. Methods are happier that way... There's no need to return struct file * from finish_open() now, so let it return int. Next: saner prototypes for parts in namei.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* make ->atomic_open() return intAl Viro2012-07-14
| | | | | | | | | | | | Change of calling conventions: old new NULL 1 file 0 ERR_PTR(-ve) -ve Caller *knows* that struct file *; no need to return it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ->atomic_open() prototype change - pass int * instead of bool *Al Viro2012-07-14
| | | | | | | | | ... and let finish_open() report having opened the file via that sucker. Next step: don't modify od->filp at all. [AV: FILE_CREATE was already used by cifs; Miklos' fix folded] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fuse: implement i_op->atomic_open()Miklos Szeredi2012-07-14
| | | | | | | | Add an ->atomic_open implementation which replaces the atomic open+create operation implemented via ->create. No functionality is changed. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: switch i_dentry/d_alias to hlistAl Viro2012-07-14
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fuse: fix blksize calculationMiklos Szeredi2012-05-14
| | | | | | | Don't use inode->i_blkbits which might be stale, instead calculate the blksize information from the freshly obtained attributes. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* fuse: fix stat call on 32 bit platformsPavel Shilovsky2012-05-14
| | | | | | | | | | | | | | Now we store attr->ino at inode->i_ino, return attr->ino at the first time and then return inode->i_ino if the attribute timeout isn't expired. That's wrong on 32 bit platforms because attr->ino is 64 bit and inode->i_ino is 32 bit in this case. Fix this by saving 64 bit ino in fuse_inode structure and returning it every time we call getattr. Also squash attr->ino into inode->i_ino explicitly. Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* fuse: O_DIRECT support for filesAnand Avati2012-03-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* fuse: fix nlink after unlinkMiklos Szeredi2012-03-05
| | | | | | | | | | | | | | | | | | | | Anand Avati reports that the following sequence of system calls fail on a fuse filesystem: create("filename") => 0 link("filename", "linkname") => 0 unlink("filename") => 0 link("linkname", "filename") => -ENOENT ### BUG ### vfs_link() fails with ENOENT if i_nlink is zero, this is done to prevent resurrecting already deleted files. Fuse clears i_nlink on unlink even if there are other links pointing to the file. Reported-by: Anand Avati <avati@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-01-12
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: FUSE: Notifying the kernel of deletion. fuse: support ioctl on directories fuse: Use kcalloc instead of kzalloc to allocate array fuse: llseek optimize SEEK_CUR and SEEK_SET
| * FUSE: Notifying the kernel of deletion.John Muir2011-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allows a FUSE file-system to tell the kernel when a file or directory is deleted. If the specified dentry has the specified inode number, the kernel will unhash it. The current 'fuse_notify_inval_entry' does not cause the kernel to clean up directories that are in use properly, and as a result the users of those directories see incorrect semantics from the file-system. The error condition seen when 'fuse_notify_inval_entry' is used to notify of a deleted directory is avoided when 'fuse_notify_delete' is used instead. The following scenario demonstrates the difference: 1. User A chdirs into 'testdir' and starts reading 'testfile'. 2. User B rm -rf 'testdir'. 3. User B creates 'testdir'. 4. User C chdirs into 'testdir'. If you run the above within the same machine on any file-system (including fuse file-systems), there is no problem: user C is able to chdir into the new testdir. The old testdir is removed from the dentry tree, but still open by user A. If operations 2 and 3 are performed via the network such that the fuse file-system uses one of the notify functions to tell the kernel that the nodes are gone, then the following error occurs for user C while user A holds the original directory open: muirj@empacher:~> ls /test/testdir ls: cannot access /test/testdir: No such file or directory The issue here is that the kernel still has a dentry for testdir, and so it is requesting the attributes for the old directory, while the file-system is responding that the directory no longer exists. If on the other hand, if the file-system can notify the kernel that the directory is deleted using the new 'fuse_notify_delete' function, then the above ls will find the new directory as expected. Signed-off-by: John Muir <john@jmuir.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
| * fuse: support ioctl on directoriesMiklos Szeredi2011-12-13
| | | | | | | | | | | | | | | | | | | | Multiplexing filesystems may want to support ioctls on the underlying files and directores (e.g. FS_IOC_{GET,SET}FLAGS). Ioctl support on directories was missing so add it now. Reported-by: Antonio SJ Musumeci <bile@landofbile.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* | fuse: propagate umode_tAl Viro2012-01-03
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | switch ->mknod() to umode_tAl Viro2012-01-03
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | switch ->create() to umode_tAl Viro2012-01-03
| | | | | | | | | | | | | | | | vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | switch vfs_mkdir() and ->mkdir() to umode_tAl Viro2012-01-03
|/ | | | | | | vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlersJosef Bacik2011-07-20
| | | | | | | | | | | | | | | Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* no need to check for LOOKUP_OPEN in ->create() instancesAl Viro2011-07-20
| | | | | | | ... it will be set in nd->flag for all cases with non-NULL nd (i.e. when called from do_last()). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* don't transliterate lower bits of ->intent.open.flags to FMODE_...Al Viro2011-07-20
| | | | | | ->create() instances are much happier that way... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ->permission() sanitizing: don't pass flags to ->permission()Al Viro2011-07-20
| | | | | | not used by the instances anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ->permission() sanitizing: don't pass flags to generic_permission()Al Viro2011-07-20
| | | | | | | redundant; all callers get it duplicated in mask & MAY_NOT_BLOCK and none of them removes that bit. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* kill check_acl callback of generic_permission()Al Viro2011-07-20
| | | | | | | its value depends only on inode and does not change; we might as well store it in ->i_op->check_acl and be done with that. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fuse: remove unnecessary dentry_unhash on rmdir, dir renameSage Weil2011-05-28
| | | | | | | | | Fuse has no problems with references to unlinked directories. CC: Miklos Szeredi <miklos@szeredi.hu> CC: fuse-devel@lists.sourceforge.net Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-05-26
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (25 commits) cifs: remove unnecessary dentry_unhash on rmdir/rename_dir ocfs2: remove unnecessary dentry_unhash on rmdir/rename_dir exofs: remove unnecessary dentry_unhash on rmdir/rename_dir nfs: remove unnecessary dentry_unhash on rmdir/rename_dir ext2: remove unnecessary dentry_unhash on rmdir/rename_dir ext3: remove unnecessary dentry_unhash on rmdir/rename_dir ext4: remove unnecessary dentry_unhash on rmdir/rename_dir btrfs: remove unnecessary dentry_unhash in rmdir/rename_dir ceph: remove unnecessary dentry_unhash calls vfs: clean up vfs_rename_other vfs: clean up vfs_rename_dir vfs: clean up vfs_rmdir vfs: fix vfs_rename_dir for FS_RENAME_DOES_D_MOVE filesystems libfs: drop unneeded dentry_unhash vfs: update dentry_unhash() comment vfs: push dentry_unhash on rename_dir into file systems vfs: push dentry_unhash on rmdir into file systems vfs: remove dget() from dentry_unhash() vfs: dentry_unhash immediately prior to rmdir vfs: Block mmapped writes while the fs is frozen ...
| * vfs: push dentry_unhash on rename_dir into file systemsSage Weil2011-05-26
| | | | | | | | | | | | | | | | | | | | Only a few file systems need this. Start by pushing it down into each rename method (except gfs2 and xfs) so that it can be dealt with on a per-fs basis. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * vfs: push dentry_unhash on rmdir into file systemsSage Weil2011-05-26
| | | | | | | | | | | | | | | | | | | | | | | | Only a few file systems need this. Start by pushing it down into each fs rmdir method (except gfs2 and xfs) so it can be dealt with on a per-fs basis. This does not change behavior for any in-tree file systems. Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | fuse: fix oops in revalidate when called with NULL nameidataMiklos Szeredi2011-05-10
|/ | | | | | | | | | | | | Some cases (e.g. ecryptfs) can call ->dentry_revalidate with NULL nameidata. https://bugzilla.kernel.org/show_bug.cgi?id=34732 Tyler Hicks pointed out that this bug was introduced by commit e7c0a16786 "fuse: make fuse_dentry_revalidate() RCU aware" Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* fuse: make fuse_dentry_revalidate() RCU awareMiklos Szeredi2011-03-21
| | | | | | | | Only bail out of fuse_dentry_revalidate() on LOOKUP_RCU when blocking is actually necessary. CC: Nick Piggin <npiggin@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* fuse: make fuse_permission() RCU awareMiklos Szeredi2011-03-21
| | | | | | | | Only bail out of fuse_permission() on IPERM_FLAG_RCU when blocking is actually necessary. CC: Nick Piggin <npiggin@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* fuse: fix d_revalidate oopsen on NFS exportsAl Viro2011-03-10
| | | | | | can't blindly check nd->flags in ->d_revalidate() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fuse: fix truncate after openMiklos Szeredi2011-02-25
| | | | | | | | | | | Commit e1181ee6 "vfs: pass struct file to do_truncate on O_TRUNC opens" broke the behavior of open(O_TRUNC|O_RDONLY) in fuse. Fuse assumed that when called from open, a truncate() will be done, not an ftruncate(). Fix by restoring the old behavior, based on the ATTR_OPEN flag. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* switch fuseAl Viro2011-01-12
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-01-10
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: fix ioctl ABI fuse: allow batching of FORGET requests fuse: separate queue for FORGET requests fuse: ioctl cleanup Fix up trivial conflict in fs/fuse/inode.c due to RCU lookup having done the RCU-freeing of the inode in fuse_destroy_inode().
| * fuse: separate queue for FORGET requestsMiklos Szeredi2010-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Terje Malmedal reports that a fuse filesystem with 32 million inodes on a machine with lots of memory can go unresponsive for up to 30 minutes when all those inodes are evicted from the icache. The reason is that FORGET messages, sent when the inode is evicted, are queued up together with regular filesystem requests, and while the huge queue of FORGET messages are processed no other filesystem operation can proceed. Since a full fuse request structure is allocated for each inode, these take up quite a bit of memory as well. To solve these issues, create a slim 'fuse_forget_link' structure containing just the minimum of information required to send the FORGET request and chain these on a separate queue. When userspace is asking for a request make sure that FORGET and non-FORGET requests are selected fairly: for each 8 non-FORGET allow 16 FORGET requests. This will make sure FORGETs do not pile up, yet other requests are also allowed to proceed while the queued FORGETs are processed. Reported-by: Terje Malmedal <terje.malmedal@usit.uio.no> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* | fs: provide rcu-walk aware permission i_opsNick Piggin2011-01-07
| | | | | | | | Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* | fs: rcu-walk aware d_revalidate methodNick Piggin2011-01-07
| | | | | | | | | | | | | | | | 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>
* | fs: dcache reduce branches in lookup pathNick Piggin2011-01-07
|/ | | | | | | | | | | | | | 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>
* Merge branch 'for-linus' of ↵Linus Torvalds2010-08-10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits) no need for list_for_each_entry_safe()/resetting with superblock list Fix sget() race with failing mount vfs: don't hold s_umount over close_bdev_exclusive() call sysv: do not mark superblock dirty on remount sysv: do not mark superblock dirty on mount btrfs: remove junk sb_dirt change BFS: clean up the superblock usage AFFS: wait for sb synchronization when needed AFFS: clean up dirty flag usage cifs: truncate fallout mbcache: fix shrinker function return value mbcache: Remove unused features add f_flags to struct statfs(64) pass a struct path to vfs_statfs update VFS documentation for method changes. All filesystems that need invalidate_inode_buffers() are doing that explicitly convert remaining ->clear_inode() to ->evict_inode() Make ->drop_inode() just return whether inode needs to be dropped fs/inode.c:clear_inode() is gone fs/inode.c:evict() doesn't care about delete vs. non-delete paths now ... Fix up trivial conflicts in fs/nilfs2/super.c
| * check ATTR_SIZE contraints in inode_change_okChristoph Hellwig2010-08-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure we check the truncate constraints early on in ->setattr by adding those checks to inode_change_ok. Also clean up and document inode_change_ok to make this obvious. As a fallout we don't have to call inode_newsize_ok from simple_setsize and simplify it down to a truncate_setsize which doesn't return an error. This simplifies a lot of setattr implementations and means we use truncate_setsize almost everywhere. Get rid of fat_setsize now that it's trivial and mark ext2_setsize static to make the calling convention obvious. Keep the inode_newsize_ok in vmtruncate for now as all callers need an audit for its removal anyway. Note: setattr code in ecryptfs doesn't call inode_change_ok at all and needs a deeper audit, but that is left for later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * always call inode_change_ok early in ->setattrChristoph Hellwig2010-08-09
| | | | | | | | | | | | | | | | | | Make sure we call inode_change_ok before doing any changes in ->setattr, and make sure to call it even if our fs wants to ignore normal UNIX permissions, but use the ATTR_FORCE to skip those. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | vfs: re-introduce MAY_CHDIREric Paris2010-08-02
|/ | | | | | | | | | | | | | Currently MAY_ACCESS means that filesystems must check the permissions right then and not rely on cached results or the results of future operations on the object. This can be because of a call to sys_access() or because of a call to chdir() which needs to check search without relying on any future operations inside that dir. I plan to use MAY_ACCESS for other purposes in the security system, so I split the MAY_ACCESS and the MAY_CHDIR cases. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* drop unused dentry argument to ->fsyncChristoph Hellwig2010-05-27
| | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fuse: reject O_DIRECT flag also in fuse_createCsaba Henk2009-11-27
| | | | | | | | | | | | | | | | | | | | The comment in fuse_open about O_DIRECT: "VFS checks this, but only _after_ ->open()" also holds for fuse_create, however, the same kind of check was missing there. As an impact of this bug, open(newfile, O_RDWR|O_CREAT|O_DIRECT) fails, but a stub newfile will remain if the fuse server handled the implied FUSE_CREATE request appropriately. Other impact: in the above situation ima_file_free() will complain to open/free imbalance if CONFIG_IMA is set. Signed-off-by: Csaba Henk <csaba@gluster.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Harshavardhana <harsha@gluster.com> Cc: stable@kernel.org
* fuse: invalidate target of renameMiklos Szeredi2009-11-04
| | | | | | | Invalidate the target's attributes, which may have changed (such as nlink, change time) so that they are refreshed on the next getattr(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* truncate: use new helpersnpiggin@suse.de2009-09-24
| | | | | | | | | | | | | | | Update some fs code to make use of new helper functions introduced in the previous patch. Should be no significant change in behaviour (except CIFS now calls send_sig under i_lock, via inode_newsize_ok). Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Cc: linux-nfs@vger.kernel.org Cc: Trond.Myklebust@netapp.com Cc: linux-cifs-client@lists.samba.org Cc: sfrench@samba.org Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fuse: invalidation reverse callsJohn Muir2009-06-30
| | | | | | | | | | | | | | | | | | | | | | | | | Add notification messages that allow the filesystem to invalidate VFS caches. Two notifications are added: 1) inode invalidation - invalidate cached attributes - invalidate a range of pages in the page cache (this is optional) 2) dentry invalidation - try to invalidate a subtree in the dentry cache Care must be taken while accessing the 'struct super_block' for the mount, as it can go away while an invalidation is in progress. To prevent this, introduce a rw-semaphore, that is taken for read during the invalidation and taken for write in the ->kill_sb callback. Cc: Csaba Henk <csaba@gluster.com> Cc: Anand Avati <avati@zresearch.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>