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path: root/fs/nfs/unlink.c
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2013-09-03NFS: Ensure that rmdir() waits for sillyrenames to completeTrond Myklebust
If an NFS client does mkdir("dir"); fd = open("dir/file"); unlink("dir/file"); close(fd); rmdir("dir"); then the asynchronous nature of the sillyrename operation means that we can end up getting EBUSY for the rmdir() in the above test. Fix that by ensuring that we wait for any in-progress sillyrenames before sending the rmdir() to the server. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-08-22NFS: Add tracepoints for debugging NFS rename and sillyrename issuesTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-08-22NFS: Clean up nfs_sillyrename()Trond Myklebust
Optimise for the case where we only do one lookup. Clean up the code so it is obvious that silly[] is not a dynamic array. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-07-05helper for reading ->d_countAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22NFS: Don't allow NFS silly-renamed files to be deleted, no signalTrond Myklebust
Commit 73ca100 broke the code that prevents the client from deleting a silly renamed dentry. This affected "delete on last close" semantics as after that commit, nothing prevented removal of silly-renamed files. As a result, a process holding a file open could easily get an ESTALE on the file in a directory where some other process issued 'rm -rf some_dir_containing_the_file' twice. Before the commit, any attempt at unlinking silly renamed files would fail inside may_delete() with -EBUSY because of the DCACHE_NFSFS_RENAMED flag. The following testcase demonstrates the problem: tail -f /nfsmnt/dir/file & rm -rf /nfsmnt/dir rm -rf /nfsmnt/dir # second removal does not fail, 'tail' process receives ESTALE The problem with the above commit is that it unhashes the old and new dentries from the lookup path, even in the normal case when a signal is not encountered and it would have been safe to call d_move. Unfortunately the old dentry has the special DCACHE_NFSFS_RENAMED flag set on it. Unhashing has the side-effect that future lookups call d_alloc(), allocating a new dentry without the special flag for any silly-renamed files. As a result, subsequent calls to unlink silly renamed files do not fail but allow the removal to go through. This will result in ESTALE errors for any other process doing operations on the file. To fix this, go back to using d_move on success. For the signal case, it's unclear what we may safely do beyond d_drop. Reported-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: Jeff Layton <jlayton@redhat.com> Cc: stable@vger.kernel.org
2013-02-17nfs: remove kfree() redundant null checksTim Gardner
smatch analysis: fs/nfs/getroot.c:130 nfs_get_root() info: redundant null check on name calling kfree() fs/nfs/unlink.c:272 nfs_async_unlink() info: redundant null check on devname_garbage calling kfree() Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: linux-nfs@vger.kernel.org Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-02-01Revert "NFS: add nfs_sb_deactive_async to avoid deadlock"Trond Myklebust
This reverts commit 324d003b0cd82151adbaecefef57b73f7959a469. The deadlock turned out to be caused by a workqueue limitation that has now been worked around in the RPC code (see comment in rpc_free_task). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-31NFS: add nfs_sb_deactive_async to avoid deadlockWeston Andros Adamson
Use nfs_sb_deactive_async instead of nfs_sb_deactive when in a workqueue context. This avoids a deadlock where rpc_shutdown_client loops forever in a workqueue kworker context, trying to kill all RPC tasks associated with the client, while one or more of these tasks have already been assigned to the same kworker (and will never run rpc_exit_task). This approach is needed because RPC tasks that have already been assigned to a kworker by queue_work cannot be canceled, as explained in the comment for workqueue.c:insert_wq_barrier. Signed-off-by: Weston Andros Adamson <dros@netapp.com> [Trond: add module_get/put.] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-06-29NFS: Create a return_delegation rpc opBryan Schumaker
Delegations are a v4 feature, so push return_delegation out of the generic client by creating a new rpc_op and renaming the old function to be in the nfs v4 "namespace" Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21NFS: Remove nfs4_setup_sequence from generic rename codeBryan Schumaker
This is an NFS v4 specific operation, so it belongs in the NFS v4 code and not the generic client. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-21NFS: Remove nfs4_setup_sequence from generic unlink codeBryan Schumaker
This is an NFS v4 specific operation, so it belongs in the NFS v4 code and not the generic client. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-11NFS: Fix a number of sparse warningsTrond Myklebust
Fix a number of "warning: symbol 'foo' was not declared. Should it be static?" conditions. Fix 2 cases of "warning: Using plain integer as NULL pointer" fs/nfs/delegation.c:263:31: warning: restricted fmode_t degrades to integer - We want to allow upgrades to a WRITE delegation, but should otherwise consider servers that hand out duplicate delegations to be borken. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31NFSv41: Add a new helper nfs4_init_sequence()Trond Myklebust
Clean up Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-10-19NFS: Get rid of nfs_restart_rpc()Trond Myklebust
It can trivially be replaced with rpc_restart_call_prepare. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-25nfs: don't use d_move in nfs_async_rename_doneJeff Layton
If the task that initiated the sillyrename ends up being killed by a fatal signal, then it will eventually return back to userspace and end up releasing the i_mutex. d_move however needs to be done while holding the i_mutex. Instead of using d_move here, just unhash the old and new dentries to prevent them from being found by lookups. With this change though, the dentries are now incorrect post-rename and do not reflect the actual name of the file on the server. I'm proceeding under the assumption that since they are unhashed that this isn't really a problem. In order for the sillydelete to still work though, the dname must be copied earlier when setting up the sillydelete info, and the name must be recopied if the sillydelete info has to be moved to a new dentry. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-15nfs: document nfsv4 sillyrename issuesJ. Bruce Fields
Somebody working on this code asked what the deal was with NFSv4, since this comment notes that it's v2/v3's statelessness that requires sillyrename. Shouldn't hurt to document the answer. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-16nfs: store devname at disconnected NFS rootsAl Viro
part 2: make sure that disconnected roots have corresponding mnt_devname values stashed into them. Have nfs*_get_root() stuff a copy of devname into ->d_fsdata of the found root, provided that it is disconnected. Have ->d_release() free it when dentry goes away. Have the places where NFS uses ->d_fsdata for sillyrename (and that can *never* happen to a disconnected root - dentry will be attached to its parent) free old devname copies if they find those. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-10SUNRPC: Close a race in __rpc_wait_for_completion_task()Trond Myklebust
Although they run as rpciod background tasks, under normal operation (i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck() and nfs4_do_close() want to be fully synchronous. This means that when we exit, we want all references to the rpc_task to be gone, and we want any dentry references etc. held by that task to be released. For this reason these functions call __rpc_wait_for_completion_task(), followed by rpc_put_task() in the expectation that the latter will be releasing the last reference to the rpc_task, and thus ensuring that the callback_ops->rpc_release() has been called synchronously. This patch fixes a race which exists due to the fact that rpciod calls rpc_complete_task() (in order to wake up the callers of __rpc_wait_for_completion_task()) and then subsequently calls rpc_put_task() without ensuring that these two steps are done atomically. In order to avoid adding new spin locks, the patch uses the existing waitqueue spin lock to order the rpc_task reference count releases between the waiting process and rpciod. The common case where nobody is waiting for completion is optimised for by checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task reference count is 1: in those cases we drop trying to grab the spin lock, and immediately free up the rpc_task. Those few processes that need to put the rpc_task from inside an asynchronous context and that do not care about ordering are given a new helper: rpc_put_task_async(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-11Merge branch 'nfs-for-2.6.38' of ↵Linus Torvalds
git://git.linux-nfs.org/projects/trondmy/nfs-2.6 * 'nfs-for-2.6.38' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (89 commits) NFS fix the setting of exchange id flag NFS: Don't use vm_map_ram() in readdir NFSv4: Ensure continued open and lockowner name uniqueness NFS: Move cl_delegations to the nfs_server struct NFS: Introduce nfs_detach_delegations() NFS: Move cl_state_owners and related fields to the nfs_server struct NFS: Allow walking nfs_client.cl_superblocks list outside client.c pnfs: layout roc code pnfs: update nfs4_callback_recallany to handle layouts pnfs: add CB_LAYOUTRECALL handling pnfs: CB_LAYOUTRECALL xdr code pnfs: change lo refcounting to atomic_t pnfs: check that partial LAYOUTGET return is ignored pnfs: add layout to client list before sending rpc pnfs: serialize LAYOUTGET(openstateid) pnfs: layoutget rpc code cleanup pnfs: change how lsegs are removed from layout list pnfs: change layout state seqlock to a spinlock pnfs: add prefix to struct pnfs_layout_hdr fields pnfs: add prefix to struct pnfs_layout_segment fields ...
2011-01-07fs: dcache scale dentry refcountNick Piggin
Make d_count non-atomic and protect it with d_lock. This allows us to ensure a 0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when we start protecting many other dentry members with d_lock. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2010-12-21NFSv4: Convert a few commas into semicolons...Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-29a couple of open-coded ihold() introduced by nfs mergeAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-09-24NFSv4.1: keep seq_res.sr_slot as pointer rather than an indexBenny Halevy
Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE resulted in numerous bugs. Keeping the current slot as a pointer to the slot table is more straight forward and robust as it's implicitly set up to NULL wherever the seq_res member is initialized to zeroes. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-21NFS: Fix a use-after-free case in nfs_async_rename()Trond Myklebust
The call to nfs_async_rename_release() after rpc_run_task() is incorrect. The rpc_run_task() is always guaranteed to call the ->rpc_release() method. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-17nfs: make sillyrename an async operationJeff Layton
A synchronous rename can be interrupted by a SIGKILL. If that happens during a sillyrename operation, it's possible for the rename call to be sent to the server, but the task exits before processing the reply. If this happens, the sillyrenamed file won't get cleaned up during nfs_dentry_iput and the server is left with a dangling .nfs* file hanging around. Fix this problem by turning sillyrename into an asynchronous operation and have the task doing the sillyrename just wait on the reply. If the task is killed before the sillyrename completes, it'll still proceed to completion. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-17nfs: move nfs_sillyrename to unlink.cJeff Layton
...since that's where most of the sillyrenaming code lives. A comment block is added to the beginning as well to clarify how sillyrenaming works. Also, make nfs_async_unlink static as nfs_sillyrename is the only caller. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-06-22NFSv4.1: Make nfs4_setup_sequence take a nfs_server argumentTrond Myklebust
In anticipation of the day when we have per-filesystem sessions, and also in order to allow the session to change in the event of a filesystem migration event. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-14NFS: Reduce stack footprint of nfs_proc_remove()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-07NFS: Fix up the declaration of nfs4_restart_rpc when NFSv4 not configuredTrond Myklebust
Also rename it: it is used in generic code, and so should not have a 'nfs4' prefix. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-05NFSv41: Clean up slot table managementTrond Myklebust
We no longer need to maintain a distinction between nfs41_sequence_done and nfs41_sequence_free_slot. This fixes a number of slot table leakages in the NFSv4.1 code. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-04nfs41: call free slot from nfs4_restart_rpcAndy Adamson
nfs41_sequence_free_slot can be called multiple times on SEQUENCE operation errors. No reason to inline nfs4_restart_rpc Reported-by: Trond Myklebust <trond.myklebust@netapp.com> nfs_writeback_done and nfs_readpage_retry call nfs4_restart_rpc outside the error handler, and the slot is not freed prior to restarting in the rpc_prepare state during session reset. Fix this by moving the call to nfs41_sequence_free_slot from the error path of nfs41_sequence_done into nfs4_restart_rpc, and by removing the test for NFS4CLNT_SESSION_SETUP. Always free slot and goto the rpc prepare state on async errors. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17nfs41: use rpc prepare call state for session resetAndy Adamson
[nfs41: change nfs4_restart_rpc argument] [nfs41: check for session not minorversion] [nfs41: trigger the state manager for session reset] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [always define nfs4_restart_rpc] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17nfs41: unlink sequence setup/done supportAndy Adamson
Implement the rpc_call_prepare methods for asynchronuos nfs rpcs, call nfs41_setup_sequence from respective rpc_call_validate_args methods. Call nfs4_sequence_done from respective rpc_call_done methods. Note that we need to pass a pointer to the nfs_server in calls data for passing on to nfs4_sequence_done. Signed-off-by: Andy Adamson<andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [pnfs: client data server write validate and release] Signed-off-by: Andy Adamson<andros@umich.edu> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfs41: separate free slot from sequence done] [nfs41: sequence res use slotid] [nfs41: remove SEQ4_STATUS_USE_TK_STATUS] [nfs41: nfs4_sequence_free_slot use nfs_client for data server] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17nfs41: set up seq_res.sr_slotidAndy Adamson
Initialize nfs4_sequence_res sr_slotid to NFS4_MAX_SLOT_TABLE. [was nfs41: sequence res use slotid] Signed-off-by: Andy Adamson <andros@netapp.com> [pulled definition of struct nfs4_sequence_res.sr_slotid to here] Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-06NFS: Clean up nfs_sb_active/nfs_sb_deactiveTrond Myklebust
Instead of causing umount requests to block on server->active_wq while the asynchronous sillyrename deletes are executing, we can use the sb->s_active counter to obtain a reference to the super_block, and then release that reference in nfs_async_unlink_release(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-27NFS: Ensure we call nfs_sb_deactive() after releasing the directory inodeTrond Myklebust
In order to avoid the "Busy inodes after unmount" error message, we need to ensure that nfs_async_unlink_release() releases the super block after the call to nfs_free_unlinkdata(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-14SUNRPC: Add a helper rpcauth_lookup_generic_cred()Trond Myklebust
The NFSv4 protocol allows clients to negotiate security protocols on the fly in the case where an administrator on the server changes the export settings and/or in the case where we may have a filesystem migration event. Instead of having the NFS client code cache credentials that are tied to a particular AUTH method it is therefore preferable to have a generic credential that can be converted into whatever AUTH is in use by the RPC client when the read/write/sillyrename/... is put on the wire. We do this by means of the new "generic" credential, which basically just caches the minimal information that is needed to look up an RPCSEC_GSS, AUTH_SYS, or AUTH_NULL credential. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS/SUNRPC: Convert all users of rpc_call_setup()Trond Myklebust
Replace use of rpc_call_setup() with rpc_init_task(), and in cases where we need to initialise task->tk_action, with rpc_call_start(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30SUNRPC: Clean up rpc_run_taskTrond Myklebust
Make it use the new task initialiser structure instead of acting as a wrapper. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS: Stop sillyname renames and unmounts from racingSteve Dickson
Added an active/deactive mechanism to the nfs_server structure allowing async operations to hold off umount until the operations are done. Signed-off-by: Steve Dickson <steved@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS: Sillyrename: in the case of a race, check aliases are really positiveTrond Myklebust
In nfs_do_call_unlink() we check that we haven't raced, and that lookup() hasn't created an aliased dentry to our sillydeleted dentry. If somebody has deleted the file on the server and the lookup() resulted in a negative dentry, then ignore... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30NFS: Fix a sillyrename race...Trond Myklebust
Ensure that readdir revalidates its data cache after blocking on sillyrename. Also fix a typo in nfs_do_call_unlink(): swap the ^= for an |=. The result is the same, since we've already checked that the flag is unset, but it makes the code more readable. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-21NFS: Fix a typo in nfs_call_unlink()Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-19Avoid compile error in fs/nfs/unlink.cLinus Torvalds
Erez Zadok reports that certain configurations fail to build due to schedule() TASK_[UN]INTERRUPTIBLE not being declared. Add proper include files to fix. Cc: Erez Zadok <ezk@cs.sunysb.edu> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19NFS: Fix a race in sillyrenameTrond Myklebust
lookup() and sillyrename() can race one another because the sillyrename() completion cannot take the parent directory's inode->i_mutex since the latter may be held by whoever is calling dput(). We therefore have little option but to add extra locking to ensure that nfs_lookup() and nfs_atomic_open() do not race with the sillyrename completion. If somebody has looked up the sillyrenamed file in the meantime, we just transfer the sillydelete information to the new dentry. Please refer to the bug-report at http://bugzilla.linux-nfs.org/show_bug.cgi?id=150 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09NFS: Remove nfs_begin_data_update/nfs_end_data_updateTrond Myklebust
The lower level routines in fs/nfs/proc.c, fs/nfs/nfs3proc.c and fs/nfs/nfs4proc.c should already be dealing with the revalidation issues. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-19SUNRPC: Clean up the sillyrename codeTrond Myklebust
Fix a couple of bugs: - Don't rely on the parent dentry still being valid when the call completes. Fixes a race with shrink_dcache_for_umount_subtree() - Don't remove the file if the filehandle has been labelled as stale. Fix a couple of inefficiencies - Remove the global list of sillyrenamed files. Instead we can cache the sillyrename information in the dentry->d_fsdata - Move common code from unlink_setup/unlink_done into fs/nfs/unlink.c Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20NFS: kzalloc conversion in fs/nfsEric Sesterhenn
this converts fs/nfs to kzalloc() usage. compile tested with make allyesconfig Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06SUNRPC: Further cleanupsTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06RPC: Clean up RPC task structureTrond Myklebust
Shrink the RPC task structure. Instead of storing separate pointers for task->tk_exit and task->tk_release, put them in a structure. Also pass the user data pointer as a parameter instead of passing it via task->tk_calldata. This enables us to nest callbacks. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>