resp_len is passed in as buffer size to decode routine; make sure it's
set right in case where userspace provides less than a page's worth of
buffer.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Stop handing garbage to userspace in the case where a weird server clears the
acl bit in the getattr return (despite the fact that they've already claimed
acl support.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Storing a pointer to the struct rpc_task in the nfs_seqid is broken
since the nfs_seqid may be freed well after the task has been destroyed.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If someone tries to rename a directory onto an empty directory, we
currently fail and return EBUSY.
This patch ensures that we try the rename if both source and target
are directories, and that we fail with a correct error of EISDIR if
the source is not a directory.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server is in the unconfirmed OPEN state for a given open owner
and receives a second OPEN for the same open owner, it will cancel the
state of the first request and set up an OPEN_CONFIRM for the second.
This can cause a race that is discussed in rfc3530 on page 181.
The following patch allows the client to recover by retrying the
original open request.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Make NFSv4 return the fully initialized file pointer with the
stateid that it created in the lookup w/intent.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We no longer need to worry about collisions between close() and the state
recovery code, since the new close will automatically recheck the
file state once it is done waiting on its sequence slot.
Ditto for the nfs4_proc_locku() procedure.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Once the state_owner and lock_owner semaphores get removed, it will be
possible for other OPEN requests to reopen the same file if they have
lower sequence ids than our CLOSE call.
This patch ensures that we recheck the file state once
nfs_wait_on_sequence() has completed waiting.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 file state-changing functions such as OPEN, CLOSE, LOCK,... are all
labelled with "sequence identifiers" in order to prevent the server from
reordering RPC requests, as this could cause its file state to
become out of sync with the client.
Currently the NFS client code enforces this ordering locally using
semaphores to restrict access to structures until the RPC call is done.
This, of course, only works with synchronous RPC calls, since the
user process must first grab the semaphore.
By dropping semaphores, and instead teaching the RPC engine to hold
the RPC calls until they are ready to be sent, we can extend this
process to work nicely with asynchronous RPC calls too.
This patch adds a new list called "rpc_sequence" that defines the order
of the RPC calls to be sent. We add one such list for each state_owner.
When an RPC call is ready to be sent, it checks if it is top of the
rpc_sequence list. If so, it proceeds. If not, it goes back to sleep,
and loops until it hits top of the list.
Once the RPC call has completed, it can then bump the sequence id counter,
and remove itself from the rpc_sequence list, and then wake up the next
sleeper.
Note that the state_owner sequence ids and lock_owner sequence ids are
all indexed to the same rpc_sequence list, so OPEN, LOCK,... requests
are all ordered w.r.t. each other.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Oopsable since nfs_wait_on_inode() can get called as part of iput_final().
Unnecessary since the caller had better be damned sure that the inode won't
disappear from underneath it anyway.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Trond Myklebust
J. Bruce Fields
Trond Myklebust