Pull vfs fixes from Al Viro:
"Assorted fixes all over the place.
The iov_iter one is this cycle regression (splice from UDP triggering
WARN_ON()), the rest is older"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
afs: Use d_instantiate() rather than d_add() and don't d_drop()
afs: Fix missing net error handling
afs: Fix validation/callback interaction
iov_iter: teach csum_and_copy_to_iter() to handle pipe-backed ones
exportfs: do not read dentry after free
exportfs: fix 'passing zero to ERR_PTR()' warning
aio: fix failure to put the file pointer
sysv: return 'err' instead of 0 in __sysv_write_inode
Use d_instantiate() rather than d_add() and don't d_drop() in
afs_vnode_new_inode(). The dentry shouldn't be removed as it's not
changing its name.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
kAFS can be given certain network errors (EADDRNOTAVAIL, EHOSTDOWN and
ERFKILL) that it doesn't handle in its server/address rotation algorithms.
They cause the probing and rotation to abort immediately rather than
rotating.
Fix this by:
(1) Abstracting out the error prioritisation from the VL and FS rotation
algorithms into a common function and expand usage into the server
probing code.
When multiple errors are available, this code selects the one we'd
prefer to return.
(2) Add handling for EADDRNOTAVAIL, EHOSTDOWN and ERFKILL.
Fixes: 0fafdc9f88 ("afs: Fix file locking")
Fixes: 0338747d8454 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When afs_validate() is called to validate a vnode (inode), there are two
unhandled cases in the fastpath at the top of the function:
(1) If the vnode is promised (AFS_VNODE_CB_PROMISED is set), the break
counters match and the data has expired, then there's an implicit case
in which the vnode needs revalidating.
This has no consequences since the default "valid = false" set at the
top of the function happens to do the right thing.
(2) If the vnode is not promised and it hasn't been deleted
(AFS_VNODE_DELETED is not set) then there's a default case we're not
handling in which the vnode is invalid. If the vnode is invalid, we
need to bring cb_s_break and cb_v_break up to date before we refetch
the status.
As a consequence, once the server loses track of the client
(ie. sufficient time has passed since we last sent it an operation),
it will send us a CB.InitCallBackState* operation when we next try to
talk to it. This calls afs_init_callback_state() which increments
afs_server::cb_s_break, but this then doesn't propagate to the
afs_vnode record.
The result being that every afs_validate() call thereafter sends a
status fetch operation to the server.
Clarify and fix this by:
(A) Setting valid in all the branches rather than initialising it at the
top so that the compiler catches where we've missed.
(B) Restructuring the logic in the 'promised' branch so that we set valid
to false if the callback is due to expire (or has expired) and so that
the final case is that the vnode is still valid.
(C) Adding an else-statement that ups cb_s_break and cb_v_break if the
promised and deleted cases don't match.
Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The life-checking function, which is used by kAFS to make sure that a call
is still live in the event of a pending signal, only samples the received
packet serial number counter; it doesn't actually provoke a change in the
counter, rather relying on the server to happen to give us a packet in the
time window.
Fix this by adding a function to force a ping to be transmitted.
kAFS then keeps track of whether there's been a stall, and if so, uses the
new function to ping the server, resetting the timeout to allow the reply
to come back.
If there's a stall, a ping and the call is *still* stalled in the same
place after another period, then the call will be aborted.
Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Fixes: f4d15fb6f9 ("rxrpc: Provide functions for allowing cleaner handling of signals")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Send probes to all the unprobed fileservers in a fileserver list on all
addresses simultaneously in an attempt to find out the fastest route whilst
not getting stuck for 20s on any server or address that we don't get a
reply from.
This alleviates the problem whereby attempting to access a new server can
take a long time because the rotation algorithm ends up rotating through
all servers and addresses until it finds one that responds.
Signed-off-by: David Howells <dhowells@redhat.com>
In some circumstances, the callback interest pointer is NULL, so in such a
case we can't dereference it when checking to see if the callback is
broken. This causes an oops in some circumstances.
Fix this by replacing the function that worked out the aggregate break
counter with one that actually does the comparison, and then make that
return true (ie. broken) if there is no callback interest as yet (ie. the
pointer is NULL).
Fixes: 68251f0a68 ("afs: Fix whole-volume callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
Eliminate the address pointer from the address list cursor as it's
redundant (ac->addrs[ac->index] can be used to find the same address) and
address lists must be replaced rather than being rearranged, so is of
limited value.
Signed-off-by: David Howells <dhowells@redhat.com>
Provide an option to allow the file or volume location server cursor to be
dumped if the rotation routine falls off the end without managing to
contact a server.
Signed-off-by: David Howells <dhowells@redhat.com>
Implement support for talking to YFS-variant fileservers in the cache
manager and the filesystem client. These implement upgraded services on
the same port as their AFS services.
YFS fileservers provide expanded capabilities over AFS.
Signed-off-by: David Howells <dhowells@redhat.com>
Expand fields in various data structures to support the expanded
information that YFS is capable of returning.
Signed-off-by: David Howells <dhowells@redhat.com>
Get the target vnode in afs_rmdir() and validate it before we attempt the
deletion, The vnode pointer will be passed through to the delivery function
in a later patch so that the delivery function can mark it deleted.
Signed-off-by: David Howells <dhowells@redhat.com>
Calculate the callback expiration time at the point of operation reply
delivery, using the reply time queried from AF_RXRPC on that call as a
base.
Signed-off-by: David Howells <dhowells@redhat.com>
The FS.FetchStatus reply delivery function was updating inode of the
directory in which a lookup had been done with the status of the looked up
file. This corrupts some of the directory state.
Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
Implement the YFS cache manager service which gives extra capabilities on
top of AFS. This is done by listening for an additional service on the
same port and indicating that anyone requesting an upgrade should be
upgraded to the YFS port.
Signed-off-by: David Howells <dhowells@redhat.com>
Remove unnecessary details of a broken callback, such as version, expiry
and type, from the afs_callback_break struct as they're not actually used
and make the list take more memory.
Signed-off-by: David Howells <dhowells@redhat.com>
Call the function to commit the status on a new file, dir or symlink so
that the access rights for the caller's key are cached for that object.
Without this, the next access to the file will cause a FetchStatus
operation to be emitted to retrieve the access rights.
Signed-off-by: David Howells <dhowells@redhat.com>
Increase the sizes of the volume ID to 64 bits and the vnode ID (inode
number equivalent) to 96 bits to allow the support of YFS.
This requires the iget comparator to check the vnode->fid rather than i_ino
and i_generation as i_ino is not sufficiently capacious. It also requires
this data to be placed into the vnode cache key for fscache.
For the moment, just discard the top 32 bits of the vnode ID when returning
it though stat.
Signed-off-by: David Howells <dhowells@redhat.com>
When writing a new page, clear space in the page rather than attempting to
load it from the server if the space is beyond the EOF.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix afs_deliver_to_call() to handle -EIO being returned by the operation
delivery function, indicating that the call found itself in the wrong
state, by printing an error and aborting the call.
Currently, an assertion failure will occur. This can happen, say, if the
delivery function falls off the end without calling afs_extract_data() with
the want_more parameter set to false to collect the end of the Rx phase of
a call.
The assertion failure looks like:
AFS: Assertion failed
4 == 7 is false
0x4 == 0x7 is false
------------[ cut here ]------------
kernel BUG at fs/afs/rxrpc.c:462!
and is matched in the trace buffer by a line like:
kworker/7:3-3226 [007] ...1 85158.030203: afs_io_error: c=0003be0c r=-5 CM_REPLY
Fixes: 98bf40cd99 ("afs: Protect call->state changes against signals")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Currently the TTL on VL server and address lists isn't set in all
circumstances and may be set to poor choices in others, since the TTL is
derived from the SRV/AFSDB DNS record if and when available.
Fix the TTL by limiting the range to a minimum and maximum from the current
time. At some point these can be made into sysctl knobs. Further, use the
TTL we obtained from the upcall to set the expiry on negative results too;
in future a mechanism can be added to force reloading of such data.
Signed-off-by: David Howells <dhowells@redhat.com>
Track VL servers as independent entities rather than lumping all their
addresses together into one set and implement server-level rotation by:
(1) Add the concept of a VL server list, where each server has its own
separate address list. This code is similar to the FS server list.
(2) Use the DNS resolver to retrieve a set of servers and their associated
addresses, ports, preference and weight ratings.
(3) In the case of a legacy DNS resolver or an address list given directly
through /proc/net/afs/cells, create a list containing just a dummy
server record and attach all the addresses to that.
(4) Implement a simple rotation policy, for the moment ignoring the
priorities and weights assigned to the servers.
(5) Show the address list through /proc/net/afs/<cell>/vlservers. This
also displays the source and status of the data as indicated by the
upcall.
Signed-off-by: David Howells <dhowells@redhat.com>
Improve the error handling in FS server rotation by:
(1) Cache the latest useful error value for the fs operation as a whole in
struct afs_fs_cursor separately from the error cached in the
afs_addr_cursor struct. The one in the address cursor gets clobbered
occasionally. Copy over the error to the fs operation only when it's
something we'd be interested in passing to userspace.
(2) Make it so that EDESTADDRREQ is the default that is seen only if no
addresses are available to be accessed.
(3) When calling utility functions, such as checking a volume status or
probing a fileserver, don't let a successful result clobber the cached
error in the cursor; instead, stash the result in a temporary variable
until it has been assessed.
(4) Don't return ETIMEDOUT or ETIME if a better error, such as
ENETUNREACH, is already cached.
(5) On leaving the rotation loop, turn any remote abort code into a more
useful error than ECONNABORTED.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
afs_extract_data sets up a temporary iov_iter and passes it to AF_RXRPC
each time it is called to describe the remaining buffer to be filled.
Instead:
(1) Put an iterator in the afs_call struct.
(2) Set the iterator for each marshalling stage to load data into the
appropriate places. A number of convenience functions are provided to
this end (eg. afs_extract_to_buf()).
This iterator is then passed to afs_extract_data().
(3) Use the new ITER_DISCARD iterator to discard any excess data provided
by FetchData.
Signed-off-by: David Howells <dhowells@redhat.com>
Linus Torvalds
David Howells