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* iget/iget5: don't bother with ->i_lock until we find a matchAl Viro2013-11-091-0/+8
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: remove vfs_follow_linkChristoph Hellwig2013-09-101-0/+4
| | | | | | | | | | | | For a long time no filesystem has been using vfs_follow_link, and as seen by recent filesystem submissions any new use is accidental as well. Remove vfs_follow_link, document the replacement in Documentation/filesystems/porting and also rename __vfs_follow_link to match its only caller better. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [readdir] ->readdir() is goneAl Viro2013-06-291-0/+3
| | | | | | everything's converted to ->iterate() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [readdir] introduce iterate_dir() and dir_contextAl Viro2013-06-291-0/+3
| | | | | | | | | | | iterate_dir(): new helper, replacing vfs_readdir(). struct dir_context: contains the readdir callback (and will get more stuff in it), embedded into whatever data that callback wants to deal with; eventually, we'll be passing it to ->readdir() replacement instead of (data,filldir) pair. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry opJeff Layton2013-02-261-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following set of operations on a NFS client and server will cause server# mkdir a client# cd a server# mv a a.bak client# sleep 30 # (or whatever the dir attrcache timeout is) client# stat . stat: cannot stat `.': Stale NFS file handle Obviously, we should not be getting an ESTALE error back there since the inode still exists on the server. The problem is that the lookup code will call d_revalidate on the dentry that "." refers to, because NFS has FS_REVAL_DOT set. nfs_lookup_revalidate will see that the parent directory has changed and will try to reverify the dentry by redoing a LOOKUP. That of course fails, so the lookup code returns ESTALE. The problem here is that d_revalidate is really a bad fit for this case. What we really want to know at this point is whether the inode is still good or not, but we don't really care what name it goes by or whether the dcache is still valid. Add a new d_op->d_weak_revalidate operation and have complete_walk call that instead of d_revalidate. The intent there is to allow for a "weaker" d_revalidate that just checks to see whether the inode is still good. This is also gives us an opportunity to kill off the FS_REVAL_DOT special casing. [AV: changed method name, added note in porting, fixed confusion re having it possibly called from RCU mode (it won't be)] Cc: NeilBrown <neilb@suse.de> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* documentation: drop vmtruncateMarco Stornelli2012-12-201-1/+1
| | | | | | | Removed vmtruncate Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Documentation: get rid of write_superArtem Bityutskiy2012-08-041-3/+2
| | | | | | | | | The '->write_super' superblock method is gone, and this patch removes all the references to 'write_super' from various pieces of the kernel documentation. Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* don't pass nameidata to ->create()Al Viro2012-07-141-0/+6
| | | | | | | | 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 Viro2012-07-141-2/+2
| | | | | | | | | 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 Viro2012-07-141-0/+5
| | | | | | Just the lookup flags. Die, bastard, die... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: update documentation on ->i_dentry handlingAl Viro2012-07-141-6/+4
| | | | | | | | we used to need to clean it in RCU callback freeing an inode; in 3.2 that requirement went away. Unfortunately, it hadn't been reflected in Documentation/filesystems/porting. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: Rename end_writeback() to clear_inode()Jan Kara2012-05-061-9/+7
| | | | | | | | | After we moved inode_sync_wait() from end_writeback() it doesn't make sense to call the function end_writeback() anymore. Rename it to clear_inode() which well says what the function really does - set I_CLEAR flag. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
* vfs: d_alloc_root() goneAl Viro2012-03-201-0/+6
| | | | | | all callers converted to d_make_root() by now Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: take the ACL checks to common codeChristoph Hellwig2011-07-251-3/+4
| | | | | | | | | Replace the ->check_acl method with a ->get_acl method that simply reads an ACL from disk after having a cache miss. This means we can replace the ACL checking boilerplate code with a single implementation in namei.c. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlersJosef Bacik2011-07-201-0/+7
| | | | | | | | | | | | | | | 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>
* fs: add SEEK_HOLE and SEEK_DATA flagsJosef Bacik2011-07-201-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | This just gets us ready to support the SEEK_HOLE and SEEK_DATA flags. Turns out using fiemap in things like cp cause more problems than it solves, so lets try and give userspace an interface that doesn't suck. We need to match solaris here, and the definitions are *o* If /whence/ is SEEK_HOLE, the offset of the start of the next hole greater than or equal to the supplied offset is returned. The definition of a hole is provided near the end of the DESCRIPTION. *o* If /whence/ is SEEK_DATA, the file pointer is set to the start of the next non-hole file region greater than or equal to the supplied offset. So in the generic case the entire file is data and there is a virtual hole at the end. That means we will just return i_size for SEEK_HOLE and will return the same offset for SEEK_DATA. This is how Solaris does it so we have to do it the same way. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ->permission() sanitizing: document API changesAl Viro2011-07-201-3/+7
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: remove inode_lock from iput_final and prune_icacheDave Chinner2011-03-241-5/+11
| | | | | | | | | | | | | | | | | | | | | Now that inode state changes are protected by the inode->i_lock and the inode LRU manipulations by the inode_lru_lock, we can remove the inode_lock from prune_icache and the initial part of iput_final(). instead of using the inode_lock to protect the inode during iput_final, use the inode->i_lock instead. This protects the inode against new references being taken while we change the inode state to I_FREEING, as well as preventing prune_icache from grabbing the inode while we are manipulating it. Hence we no longer need the inode_lock in iput_final prior to setting I_FREEING on the inode. For prune_icache, we no longer need the inode_lock to protect the LRU list, and the inodes themselves are protected against freeing races by the inode->i_lock. Hence we can lift the inode_lock from prune_icache as well. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: bury ->get_sb()Al Viro2011-03-161-0/+7
| | | | | | This is an ex-parrot. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'vfs-scale-working' of ↵Linus Torvalds2011-01-131-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin * 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: fs: fix do_last error case when need_reval_dot nfs: add missing rcu-walk check fs: hlist UP debug fixup fs: fix dropping of rcu-walk from force_reval_path fs: force_reval_path drop rcu-walk before d_invalidate fs: small rcu-walk documentation fixes Fixed up trivial conflicts in Documentation/filesystems/porting
| * fs: small rcu-walk documentation fixesNick Piggin2011-01-141-4/+4
| | | | | | | | Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* | fs: add documentation on fallocate hole punchingJosef Bacik2011-01-121-0/+9
|/ | | | | | | | This patch simply adds documentation on how to handle the hole punching mode of fallocate for any filesystem wishing to use it. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: provide rcu-walk aware permission i_opsNick Piggin2011-01-071-0/+5
| | | | Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* fs: rcu-walk aware d_revalidate methodNick Piggin2011-01-071-0/+20
| | | | | | | | 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: icache RCU free inodesNick Piggin2011-01-071-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* fs: dcache remove dcache_lockNick Piggin2011-01-071-1/+7
| | | | | | dcache_lock no longer protects anything. remove it. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* fs: change d_hash for rcu-walkNick Piggin2011-01-071-0/+7
| | | | | | | | | Change d_hash so it may be called from lock-free RCU lookups. See similar patch for d_compare for details. For in-tree filesystems, this is just a mechanical change. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* fs: change d_compare for rcu-walkNick Piggin2011-01-071-0/+7
| | | | | | | | | | | | | Change d_compare so it may be called from lock-free RCU lookups. This does put significant restrictions on what may be done from the callback, however there don't seem to have been any problems with in-tree fses. If some strange use case pops up that _really_ cannot cope with the rcu-walk rules, we can just add new rcu-unaware callbacks, which would cause name lookup to drop out of rcu-walk mode. For in-tree filesystems, this is just a mechanical change. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* fs: change d_delete semanticsNick Piggin2011-01-071-0/+8
| | | | | | | | | | | | Change d_delete from a dentry deletion notification to a dentry caching advise, more like ->drop_inode. Require it to be constant and idempotent, and not take d_lock. This is how all existing filesystems use the callback anyway. This makes fine grained dentry locking of dput and dentry lru scanning much simpler. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* update VFS documentation for method changes.Al Viro2010-08-091-0/+27
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* update documentation for the new truncate sequenceChristoph Hellwig2010-08-091-0/+18
| | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* nfs: new subdir Documentation/filesystems/nfsJ. Bruce Fields2009-10-271-1/+1
| | | | | | | | We're adding enough nfs documentation that it may as well have its own subdirectory. Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* iget: remove iget() and the read_inode() super op as being obsoleteDavid Howells2008-02-071-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the old iget() call and the read_inode() superblock operation it uses as these are really obsolete, and the use of read_inode() does not produce proper error handling (no distinction between ENOMEM and EIO when marking an inode bad). Furthermore, this removes the temptation to use iget() to find an inode by number in a filesystem from code outside that filesystem. iget_locked() should be used instead. A new function is added in an earlier patch (iget_failed) that is to be called to mark an inode as bad, unlock it and release it should the get routine fail. Mark iget() and read_inode() as being obsolete and remove references to them from the documentation. Typically a filesystem will be modified such that the read_inode function becomes an internal iget function, for example the following: void thingyfs_read_inode(struct inode *inode) { ... } would be changed into something like: struct inode *thingyfs_iget(struct super_block *sp, unsigned long ino) { struct inode *inode; int ret; inode = iget_locked(sb, ino); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) return inode; ... unlock_new_inode(inode); return inode; error: iget_failed(inode); return ERR_PTR(ret); } and then thingyfs_iget() would be called rather than iget(), for example: ret = -EINVAL; inode = iget(sb, ino); if (!inode || is_bad_inode(inode)) goto error; becomes: inode = thingyfs_iget(sb, ino); if (IS_ERR(inode)) { ret = PTR_ERR(inode); goto error; } Note that is_bad_inode() does not need to be called. The error returned by thingyfs_iget() should render it unnecessary. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* iget: introduce a function to register iget failureDavid Howells2008-02-071-5/+13
| | | | | | | | | | | Introduce a function to register failure in an inode construction path. This includes marking the inode under construction as bad, unlocking it and releasing it. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation/filesystems/porting fixesOliver Pinter2008-02-031-3/+3
| | | | | | | typo fix and whitespace cleanup Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
* Documentation: Fix up docs still talking about i_semJosef 'Jeff' Sipek2007-05-241-4/+4
| | | | | | | .. it got changed to 'i_mutex' some time ago. Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] VFS: Permit filesystem to override root dentry on mountDavid Howells2006-06-231-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+266
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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