Further fix the file locking in the afs filesystem client in a number of
ways, including:
(1) Don't submit the operation to obtain a lock from the server in a work
queue context, but rather do it in the process context of whoever
issued the requesting system call.
(2) The owner of the file_lock struct at the front of the pending_locks
queue now owns right to talk to the server.
(3) Write locks can be instantly granted if they don't overlap with any
other locks *and* we have a write lock on the server.
(4) In the event of an authentication/permission error, all other matching
pending locks requests are also immediately aborted.
(5) Properly use VFS core locks_lock_file_wait() to distribute the server
lock amongst local client locks, including waiting for the lock to
become available.
Test with:
sqlite3 /afs/.../scratch/billings.sqlite <<EOF
CREATE TABLE hosts (
hostname varchar(80),
shorthost varchar(80),
room varchar(30),
building varchar(30),
PRIMARY KEY(shorthost)
);
EOF
With the version of sqlite3 that I have, this should fail consistently with
EAGAIN, whether or not the program is straced (which introduces some delays
between lock syscalls).
Fixes: 0fafdc9f88 ("afs: Fix file locking")
Reported-by: Jonathan Billings <jsbillin@umich.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Fix AFS file locking to allow fine grained locks as some applications, such
as firefox, won't work if they can't take such locks on certain state files
- thereby preventing the use of kAFS to distribute a home directory.
Note that this cannot be made completely functional as the protocol only
has provision for whole-file locks, so there exists the possibility of a
process deadlocking itself by getting a partial read-lock on a file first
and then trying to get a non-overlapping write-lock - but we got the
server's read lock with the first lock, so we're now stuck.
OpenAFS solves this by just granting any partial-range lock directly
without consulting the server - and hoping there's no remote collision. I
want to implement that in a separate patch and it requires a bit more
thought.
Fixes: 8d6c554126b8 ("AFS: implement file locking")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Record the timestamp on the first reply DATA packet received in response to
a set- or extend-lock operation, then use this to calculate the time
remaining till the lock expires rather than using whatever time the
requesting process wakes up and finishes processing the operation as a
base.
Signed-off-by: David Howells <dhowells@redhat.com>
Split the call to afs_wait_for_call_to_complete() from afs_make_call() to
make it easier to handle asynchronous calls and to make it easier to
convert a synchronous call to an asynchronous one in future, for instance
when someone tries to interrupt an operation by pressing Ctrl-C.
Signed-off-by: David Howells <dhowells@redhat.com>
The in-kernel afs filesystem client counts the number of server-level
callback invalidation events (CB.InitCallBackState* RPC operations) that it
receives from the server. This is stored in cb_s_break in various
structures, including afs_server and afs_vnode.
If an inode is examined by afs_validate(), say, the afs_server copy is
compared, along with other break counters, to those in afs_vnode, and if
one or more of the counters do not match, it is considered that the
server's callback promise is broken. At points where this happens,
AFS_VNODE_CB_PROMISED is cleared to indicate that the status must be
refetched from the server.
afs_validate() issues an FS.FetchStatus operation to get updated metadata -
and based on the updated data_version may invalidate the pagecache too.
However, the break counters are also used to determine whether to note a
new callback in the vnode (which would set the AFS_VNODE_CB_PROMISED flag)
and whether to cache the permit data included in the YFSFetchStatus record
by the server.
The problem comes when the server sends us a CB.InitCallBackState op. The
first such instance doesn't cause cb_s_break to be incremented, but rather
causes AFS_SERVER_FL_NEW to be cleared - but thereafter, say some hours
after last use and all the volumes have been automatically unmounted and
the server has forgotten about the client[*], this *will* likely cause an
increment.
[*] There are other circumstances too, such as the server restarting or
needing to make space in its callback table.
Note that the server won't send us a CB.InitCallBackState op until we talk
to it again.
So what happens is:
(1) A mount for a new volume is attempted, a inode is created for the root
vnode and vnode->cb_s_break and AFS_VNODE_CB_PROMISED aren't set
immediately, as we don't have a nominated server to talk to yet - and
we may iterate through a few to find one.
(2) Before the operation happens, afs_fetch_status(), say, notes in the
cursor (fc.cb_break) the break counter sum from the vnode, volume and
server counters, but the server->cb_s_break is currently 0.
(3) We send FS.FetchStatus to the server. The server sends us back
CB.InitCallBackState. We increment server->cb_s_break.
(4) Our FS.FetchStatus completes. The reply includes a callback record.
(5) xdr_decode_AFSCallBack()/xdr_decode_YFSCallBack() check to see whether
the callback promise was broken by checking the break counter sum from
step (2) against the current sum.
This fails because of step (3), so we don't set the callback record
and, importantly, don't set AFS_VNODE_CB_PROMISED on the vnode.
This does not preclude the syscall from progressing, and we don't loop here
rechecking the status, but rather assume it's good enough for one round
only and will need to be rechecked next time.
(6) afs_validate() it triggered on the vnode, probably called from
d_revalidate() checking the parent directory.
(7) afs_validate() notes that AFS_VNODE_CB_PROMISED isn't set, so doesn't
update vnode->cb_s_break and assumes the vnode to be invalid.
(8) afs_validate() needs to calls afs_fetch_status(). Go back to step (2)
and repeat, every time the vnode is validated.
This primarily affects volume root dir vnodes. Everything subsequent to
those inherit an already incremented cb_s_break upon mounting.
The issue is that we assume that the callback record and the cached permit
information in a reply from the server can't be trusted after getting a
server break - but this is wrong since the server makes sure things are
done in the right order, holding up our ops if necessary[*].
[*] There is an extremely unlikely scenario where a reply from before the
CB.InitCallBackState could get its delivery deferred till after - at
which point we think we have a promise when we don't. This, however,
requires unlucky mass packet loss to one call.
AFS_SERVER_FL_NEW tries to paper over the cracks for the initial mount from
a server we've never contacted before, but this should be unnecessary.
It's also further insulated from the problem on an initial mount by
querying the server first with FS.GetCapabilities, which triggers the
CB.InitCallBackState.
Fix this by
(1) Remove AFS_SERVER_FL_NEW.
(2) In afs_calc_vnode_cb_break(), don't include cb_s_break in the
calculation.
(3) In afs_cb_is_broken(), don't include cb_s_break in the check.
Signed-off-by: David Howells <dhowells@redhat.com>
__pagevec_release() complains loudly if any page in the vector is still
locked. The pages need to be locked for generic_error_remove_page(), but
that function doesn't actually unlock them.
Unlock the pages afterwards.
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jonathan Billings <jsbillin@umich.edu>
Differentiate an abort due to an unmarshalling error from an abort due to
other errors, such as ENETUNREACH. It doesn't make sense to set abort code
RXGEN_*_UNMARSHAL in such a case, so use RX_USER_ABORT instead.
Signed-off-by: David Howells <dhowells@redhat.com>
__tracepoint_str cannot be const because the tracepoint_str
section is not read-only. Remove the stray const.
Cc: dhowells@redhat.com
Cc: viro@zeniv.linux.org.uk
Signed-off-by: Andi Kleen <ak@linux.intel.com>
get_seconds() has a limited range on 32-bit architectures and is
deprecated because of that. While AFS uses the same limits for
its inode timestamps on the wire protocol, let's just use the
simpler current_time() as we do for other file systems.
This will still zero out the 'tv_nsec' field of the timestamps
internally.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Check the state of the rxrpc call backing an afs call in each iteration of
the call wait loop in case the rxrpc call has already been terminated at
the rxrpc layer.
Interrupt the wait loop and mark the afs call as complete if the rxrpc
layer call is complete.
There were cases where rxrpc errors were not passed up to afs, which could
result in this loop waiting forever for an afs call to transition to
AFS_CALL_COMPLETE while the rx call was already complete.
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make rxrpc_kernel_check_life() pass back the life counter through the
argument list and return true if the call has not yet completed.
Suggested-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in many cases I placed a /* Fall through */ comment
at the bottom of the case, which what GCC is expecting to find.
In other cases I had to tweak a bit the format of the comments.
This patch suppresses ALL missing-break-in-switch false positives
in fs/afs
Addresses-Coverity-ID: 115042 ("Missing break in switch")
Addresses-Coverity-ID: 115043 ("Missing break in switch")
Addresses-Coverity-ID: 115045 ("Missing break in switch")
Addresses-Coverity-ID: 1357430 ("Missing break in switch")
Addresses-Coverity-ID: 115047 ("Missing break in switch")
Addresses-Coverity-ID: 115050 ("Missing break in switch")
Addresses-Coverity-ID: 115051 ("Missing break in switch")
Addresses-Coverity-ID: 1467806 ("Missing break in switch")
Addresses-Coverity-ID: 1467807 ("Missing break in switch")
Addresses-Coverity-ID: 1467811 ("Missing break in switch")
Addresses-Coverity-ID: 115041 ("Missing break in switch")
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
The marshalling of AFS.StoreData, AFS.StoreData64 and YFS.StoreData64 calls
generated by ->setattr() ops for the purpose of expanding a file is
incorrect due to older documentation incorrectly describing the way the RPC
'FileLength' parameter is meant to work.
The older documentation says that this is the length the file is meant to
end up at the end of the operation; however, it was never implemented this
way in any of the servers, but rather the file is truncated down to this
before the write operation is effected, and never expanded to it (and,
indeed, it was renamed to 'TruncPos' in 2014).
Fix this by setting the position parameter to the new file length and doing
a zero-lengh write there.
The bug causes Xwayland to SIGBUS due to unexpected non-expansion of a file
it then mmaps. This can be tested by giving the following test program a
filename in an AFS directory:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
int main(int argc, char *argv[])
{
char *p;
int fd;
if (argc != 2) {
fprintf(stderr,
"Format: test-trunc-mmap <file>\n");
exit(2);
}
fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC);
if (fd < 0) {
perror(argv[1]);
exit(1);
}
if (ftruncate(fd, 0x140008) == -1) {
perror("ftruncate");
exit(1);
}
p = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, 0);
if (p == MAP_FAILED) {
perror("mmap");
exit(1);
}
p[0] = 'a';
if (munmap(p, 4096) < 0) {
perror("munmap");
exit(1);
}
if (close(fd) < 0) {
perror("close");
exit(1);
}
exit(0);
}
Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Jonathan Billings <jsbillin@umich.edu>
Tested-by: Jonathan Billings <jsbillin@umich.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs mount infrastructure updates from Al Viro:
"The rest of core infrastructure; no new syscalls in that pile, but the
old parts are switched to new infrastructure. At that point
conversions of individual filesystems can happen independently; some
are done here (afs, cgroup, procfs, etc.), there's also a large series
outside of that pile dealing with NFS (quite a bit of option-parsing
stuff is getting used there - it's one of the most convoluted
filesystems in terms of mount-related logics), but NFS bits are the
next cycle fodder.
It got seriously simplified since the last cycle; documentation is
probably the weakest bit at the moment - I considered dropping the
commit introducing Documentation/filesystems/mount_api.txt (cutting
the size increase by quarter ;-), but decided that it would be better
to fix it up after -rc1 instead.
That pile allows to do followup work in independent branches, which
should make life much easier for the next cycle. fs/super.c size
increase is unpleasant; there's a followup series that allows to
shrink it considerably, but I decided to leave that until the next
cycle"
* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
afs: Use fs_context to pass parameters over automount
afs: Add fs_context support
vfs: Add some logging to the core users of the fs_context log
vfs: Implement logging through fs_context
vfs: Provide documentation for new mount API
vfs: Remove kern_mount_data()
hugetlbfs: Convert to fs_context
cpuset: Use fs_context
kernfs, sysfs, cgroup, intel_rdt: Support fs_context
cgroup: store a reference to cgroup_ns into cgroup_fs_context
cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
cgroup_do_mount(): massage calling conventions
cgroup: stash cgroup_root reference into cgroup_fs_context
cgroup2: switch to option-by-option parsing
cgroup1: switch to option-by-option parsing
cgroup: take options parsing into ->parse_monolithic()
cgroup: fold cgroup1_mount() into cgroup1_get_tree()
cgroup: start switching to fs_context
ipc: Convert mqueue fs to fs_context
proc: Add fs_context support to procfs
...
All users of VM_MAX_READAHEAD actually convert it to kbytes and then to
pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This
simplifies the expression in every filesystem. Also rename the macro to
VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused
VM_MIN_READAHEAD
[akpm@linux-foundation.org: fix fs/io_uring.c, per Stephen]
Link: http://lkml.kernel.org/r/20181221144053.24318-1-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alter the AFS automounting code to create and modify an fs_context struct
when parameterising a new mount triggered by an AFS mountpoint rather than
constructing device name and option strings.
Also remove the cell=, vol= and rwpath options as they are then redundant.
The reason they existed is because the 'device name' may be derived
literally from a mountpoint object in the filesystem, so default cell and
parent-type information needed to be passed in by some other method from
the automount routines. The vol= option didn't end up being used.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric W. Biederman <ebiederm@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add fs_context support to the AFS filesystem, converting the parameter
parsing to store options there.
This will form the basis for namespace propagation over mountpoints within
the AFS model, thereby allowing AFS to be used in containers more easily.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When a cell with a volume location server list is added manually by
echoing the details into /proc/net/afs/cells, a record is added but the
flag saying it has been looked up isn't set.
This causes the VL server rotation code to wait forever, with the top of
/proc/pid/stack looking like:
afs_select_vlserver+0x3a6/0x6f3
afs_vl_lookup_vldb+0x4b/0x92
afs_create_volume+0x25/0x1b9
...
with the thread stuck in afs_start_vl_iteration() waiting for
AFS_CELL_FL_NO_LOOKUP_YET to be cleared.
Fix this by clearing AFS_CELL_FL_NO_LOOKUP_YET when setting up a record
if that record's details were supplied manually.
Fixes: 0a5143f2f8 ("afs: Implement VL server rotation")
Reported-by: Dave Botsch <dwb7@cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's a race between afs_make_call() and afs_wake_up_async_call() in the
case that an error is returned from rxrpc_kernel_send_data() after it has
queued the final packet.
afs_make_call() will try and clean up the mess, but the call state may have
been moved on thereby causing afs_process_async_call() to also try and to
delete the call.
Fix this by:
(1) Getting an extra ref for an asynchronous call for the call itself to
hold. This makes sure the call doesn't evaporate on us accidentally
and will allow the call to be retained by the caller in a future
patch. The ref is released on leaving afs_make_call() or
afs_wait_for_call_to_complete().
(2) In the event of an error from rxrpc_kernel_send_data():
(a) Don't set the call state to AFS_CALL_COMPLETE until *after* the
call has been aborted and ended. This prevents
afs_deliver_to_call() from doing anything with any notifications
it gets.
(b) Explicitly end the call immediately to prevent further callbacks.
(c) Cancel any queued async_work and wait for the work if it's
executing. This allows us to be sure the race won't recur when we
change the state. We put the work queue's ref on the call if we
managed to cancel it.
(d) Put the call's ref that we got in (1). This belongs to us as long
as the call is in state AFS_CALL_CL_REQUESTING.
Fixes: 341f741f04 ("afs: Refcount the afs_call struct")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the refcounting of the authentication keys in the file locking code.
The vnode->lock_key member points to a key on which it expects to be
holding a ref, but it isn't always given an extra ref, however.
Fixes: 0fafdc9f88 ("afs: Fix file locking")
Signed-off-by: David Howells <dhowells@redhat.com>
A cb_interest record is not necessarily attached to the vnode on entry to
afs_validate(), which can cause an oops when we try to bring the vnode's
cb_s_break up to date in the default case (ie. no current callback promise
and the vnode has not been deleted).
Fix this by simply removing the line, as vnode->cb_s_break will be set when
needed by afs_register_server_cb_interest() when we next get a callback
promise from RPC call.
The oops looks something like:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
...
RIP: 0010:afs_validate+0x66/0x250 [kafs]
...
Call Trace:
afs_d_revalidate+0x8d/0x340 [kafs]
? __d_lookup+0x61/0x150
lookup_dcache+0x44/0x70
? lookup_dcache+0x44/0x70
__lookup_hash+0x24/0xa0
do_unlinkat+0x11d/0x2c0
__x64_sys_unlink+0x23/0x30
do_syscall_64+0x4d/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: ae3b7361dc ("afs: Fix validation/callback interaction")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
A lock type of 0 is "LockRead", which makes the fileserver record an
unintentional read lock on the new file. This will cause problems
later on if the file is the subject of locking operations.
The correct default value should be -1 ("LockNone").
Fix the operation marshalling code to set the value and provide an enum to
symbolise the values whilst we're at it.
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
One of the more common cases of allocation size calculations is finding the
size of a structure that has a zero-sized array at the end, along with
memory for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};
instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can now
use the new struct_size() helper:
instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Multiple filesystems open code lru_to_page(). Rectify this by moving
the macro from mm_inline (which is specific to lru stuff) to the more
generic mm.h header and start using the macro where appropriate.
No functional changes.
Link: http://lkml.kernel.org/r/20181129104810.23361-1-nborisov@suse.com
Link: https://lkml.kernel.org/r/20181129075301.29087-1-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Pankaj gupta <pagupta@redhat.com>
Acked-by: "Yan, Zheng" <zyan@redhat.com> [ceph]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is already done for us internally by the signal machinery.
[akpm@linux-foundation.org: fix fs/buffer.c]
Link: http://lkml.kernel.org/r/20181116002713.8474-7-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
Include the site of detection of AFS protocol errors in trace lines to
better be able to determine what went wrong.
Signed-off-by: David Howells <dhowells@redhat.com>
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.
Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.
Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.
Signed-off-by: David Howells <dhowells@redhat.com>
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.
net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'. Thanks to David
Ahern for the heads up.
Signed-off-by: David S. Miller <davem@davemloft.net>
The recent patch to fix the afs_server struct leak didn't actually fix the
bug, but rather fixed some of the symptoms. The problem is that an
asynchronous call that holds a resource pointed to by call->reply[0] will
find the pointer cleared in the call destructor, thereby preventing the
resource from being cleaned up.
In the case of the server record leak, the afs_fs_get_capabilities()
function in devel code sets up a call with reply[0] pointing at the server
record that should be altered when the result is obtained, but this was
being cleared before the destructor was called, so the put in the
destructor does nothing and the record is leaked.
Commit f014ffb025 removed the additional ref obtained by
afs_install_server(), but the removal of this ref is actually used by the
garbage collector to mark a server record as being defunct after the record
has expired through lack of use.
The offending clearance of call->reply[0] upon completion in
afs_process_async_call() has been there from the origin of the code, but
none of the asynchronous calls actually use that pointer currently, so it
should be safe to remove (note that synchronous calls don't involve this
function).
Fix this by the following means:
(1) Revert commit f014ffb025.
(2) Remove the clearance of reply[0] from afs_process_async_call().
Without this, afs_manage_servers() will suffer an assertion failure if it
sees a server record that didn't get used because the usage count is not 1.
Fixes: f014ffb025 ("afs: Fix afs_server struct leak")
Fixes: 08e0e7c82e ("[AF_RXRPC]: Make the in-kernel AFS filesystem use AF_RXRPC.")
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Conflicts were easy to resolve using immediate context mostly,
except the cls_u32.c one where I simply too the entire HEAD
chunk.
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a leak of afs_server structs. The routine that installs them in the
various lookup lists and trees gets a ref on leaving the function, whether
it added the server or a server already exists. It shouldn't increment
the refcount if it added the server.
The effect of this that "rmmod kafs" will hang waiting for the leaked
server to become unused.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Access to the list of cells by /proc/net/afs/cells has a couple of
problems:
(1) It should be checking against SEQ_START_TOKEN for the keying the
header line.
(2) It's only holding the RCU read lock, so it can't just walk over the
list without following the proper RCU methods.
Fix these by using an hlist instead of an ordinary list and using the
appropriate accessor functions to follow it with RCU.
Since the code that adds a cell to the list must also necessarily change,
sort the list on insertion whilst we're at it.
Fixes: 989782dcdc ("afs: Overhaul cell database management")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
AF_RXRPC opens an IPv6 socket through which to send and receive network
packets, both IPv6 and IPv4. It currently turns AF_INET addresses into
AF_INET-as-AF_INET6 addresses based on an assumption that this was
necessary; on further inspection of the code, however, it turns out that
the IPv6 code just farms packets aimed at AF_INET addresses out to the IPv4
code.
Fix AF_RXRPC to use AF_INET addresses directly when given them.
Fixes: 7b674e390e ("rxrpc: Fix IPv6 support")
Signed-off-by: David Howells <dhowells@redhat.com>
Sort address lists so that they are in logical ascending order rather than
being partially in ascending order of the BE representations of those
values.
Signed-off-by: David Howells <dhowells@redhat.com>
Make the address list string parser use the helper functions for adding
addresses to an address list so that they end up appropriately sorted.
This will better handles overruns and make them easier to compare.
It also reduces the number of places that addresses are handled, making it
easier to fix the handling.
Signed-off-by: David Howells <dhowells@redhat.com>
Note the maximum allocated capacity in an afs_addr_list struct and discard
addresses that would exceed it in afs_merge_fs_addr{4,6}().
Also, since the current maximum capacity is less than 255, reduce the
relevant members to bytes.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the cell specification mechanism to allow cells to be pre-created
without having to specify at least one address (the addresses will be
upcalled for).
This allows the cell information preload service to avoid the need to issue
loads of DNS lookups during boot to get the addresses for each cell (500+
lookups for the 'standard' cell list[*]). The lookups can be done later as
each cell is accessed through the filesystem.
Also remove the print statement that prints a line every time a new cell is
added.
[*] There are 144 cells in the list. Each cell is first looked up for an
SRV record, and if that fails, for an AFSDB record. These get a list
of server names, each of which then has to be looked up to get the
addresses for that server. E.g.:
dig srv _afs3-vlserver._udp.grand.central.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use new return type vm_fault_t for fault handler in struct
vm_operations_struct. For now, this is just documenting that the
function returns a VM_FAULT value rather than an errno. Once all
instances are converted, vm_fault_t will become a distinct type.
See 1c8f422059 ("mm: change return type to vm_fault_t") for reference.
Link: http://lkml.kernel.org/r/20180702152017.GA3780@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking updates from David Miller:
"Highlights:
- Gustavo A. R. Silva keeps working on the implicit switch fallthru
changes.
- Support 802.11ax High-Efficiency wireless in cfg80211 et al, From
Luca Coelho.
- Re-enable ASPM in r8169, from Kai-Heng Feng.
- Add virtual XFRM interfaces, which avoids all of the limitations of
existing IPSEC tunnels. From Steffen Klassert.
- Convert GRO over to use a hash table, so that when we have many
flows active we don't traverse a long list during accumluation.
- Many new self tests for routing, TC, tunnels, etc. Too many
contributors to mention them all, but I'm really happy to keep
seeing this stuff.
- Hardware timestamping support for dpaa_eth/fsl-fman from Yangbo Lu.
- Lots of cleanups and fixes in L2TP code from Guillaume Nault.
- Add IPSEC offload support to netdevsim, from Shannon Nelson.
- Add support for slotting with non-uniform distribution to netem
packet scheduler, from Yousuk Seung.
- Add UDP GSO support to mlx5e, from Boris Pismenny.
- Support offloading of Team LAG in NFP, from John Hurley.
- Allow to configure TX queue selection based upon RX queue, from
Amritha Nambiar.
- Support ethtool ring size configuration in aquantia, from Anton
Mikaev.
- Support DSCP and flowlabel per-transport in SCTP, from Xin Long.
- Support list based batching and stack traversal of SKBs, this is
very exciting work. From Edward Cree.
- Busyloop optimizations in vhost_net, from Toshiaki Makita.
- Introduce the ETF qdisc, which allows time based transmissions. IGB
can offload this in hardware. From Vinicius Costa Gomes.
- Add parameter support to devlink, from Moshe Shemesh.
- Several multiplication and division optimizations for BPF JIT in
nfp driver, from Jiong Wang.
- Lots of prepatory work to make more of the packet scheduler layer
lockless, when possible, from Vlad Buslov.
- Add ACK filter and NAT awareness to sch_cake packet scheduler, from
Toke Høiland-Jørgensen.
- Support regions and region snapshots in devlink, from Alex Vesker.
- Allow to attach XDP programs to both HW and SW at the same time on
a given device, with initial support in nfp. From Jakub Kicinski.
- Add TLS RX offload and support in mlx5, from Ilya Lesokhin.
- Use PHYLIB in r8169 driver, from Heiner Kallweit.
- All sorts of changes to support Spectrum 2 in mlxsw driver, from
Ido Schimmel.
- PTP support in mv88e6xxx DSA driver, from Andrew Lunn.
- Make TCP_USER_TIMEOUT socket option more accurate, from Jon
Maxwell.
- Support for templates in packet scheduler classifier, from Jiri
Pirko.
- IPV6 support in RDS, from Ka-Cheong Poon.
- Native tproxy support in nf_tables, from Máté Eckl.
- Maintain IP fragment queue in an rbtree, but optimize properly for
in-order frags. From Peter Oskolkov.
- Improvde handling of ACKs on hole repairs, from Yuchung Cheng"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1996 commits)
bpf: test: fix spelling mistake "REUSEEPORT" -> "REUSEPORT"
hv/netvsc: Fix NULL dereference at single queue mode fallback
net: filter: mark expected switch fall-through
xen-netfront: fix warn message as irq device name has '/'
cxgb4: Add new T5 PCI device ids 0x50af and 0x50b0
net: dsa: mv88e6xxx: missing unlock on error path
rds: fix building with IPV6=m
inet/connection_sock: prefer _THIS_IP_ to current_text_addr
net: dsa: mv88e6xxx: bitwise vs logical bug
net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd()
ieee802154: hwsim: using right kind of iteration
net: hns3: Add vlan filter setting by ethtool command -K
net: hns3: Set tx ring' tc info when netdev is up
net: hns3: Remove tx ring BD len register in hns3_enet
net: hns3: Fix desc num set to default when setting channel
net: hns3: Fix for phy link issue when using marvell phy driver
net: hns3: Fix for information of phydev lost problem when down/up
net: hns3: Fix for command format parsing error in hclge_is_all_function_id_zero
net: hns3: Add support for serdes loopback selftest
bnxt_en: take coredump_record structure off stack
...
Pull vfs lookup() updates from Al Viro:
"More conversions of ->lookup() to d_splice_alias().
Should be reasonably complete now - the only leftovers are in ceph"
* 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
afs_try_auto_mntpt(): return NULL instead of ERR_PTR(-ENOENT)
afs_lookup(): switch to d_splice_alias()
afs: switch dynroot lookups to d_splice_alias()
hpfs: fix an inode leak in lookup, switch to d_splice_alias()
hostfs_lookup: switch to d_splice_alias()
->lookup() methods can (and should) use d_splice_alias() instead of
d_add(). Even if they are not going to be hit by open_by_handle(),
code does get copied around; besides, d_splice_alias() has better
calling conventions for use in ->lookup(), so the code gets simpler.
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
->lookup() methods can (and should) use d_splice_alias() instead of
d_add(). Even if they are not going to be hit by open_by_handle(),
code does get copied around...
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Push iov_iter up from rxrpc_kernel_recv_data() to its caller to allow
non-contiguous iovs to be passed down, thereby permitting file reading to
be simplified in the AFS filesystem in a future patch.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While __atomic_add_unless() was originally intended as a building-block
for atomic_add_unless(), it's now used in a number of places around the
kernel. It's the only common atomic operation named __atomic*(), rather
than atomic_*(), and for consistency it would be better named
atomic_fetch_add_unless().
This lack of consistency is slightly confusing, and gets in the way of
scripting atomics. Given that, let's clean things up and promote it to
an official part of the atomics API, in the form of
atomic_fetch_add_unless().
This patch converts definitions and invocations over to the new name,
including the instrumented version, using the following script:
----
git grep -w __atomic_add_unless | while read line; do
sed -i '{s/\<__atomic_add_unless\>/atomic_fetch_add_unless/}' "${line%%:*}";
done
git grep -w __arch_atomic_add_unless | while read line; do
sed -i '{s/\<__arch_atomic_add_unless\>/arch_atomic_fetch_add_unless/}' "${line%%:*}";
done
----
Note that we do not have atomic{64,_long}_fetch_add_unless(), which will
be introduced by later patches.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Palmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-2-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull AFS updates from Al Viro:
"Assorted AFS stuff - ended up in vfs.git since most of that consists
of David's AFS-related followups to Christoph's procfs series"
* 'afs-proc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
afs: Optimise callback breaking by not repeating volume lookup
afs: Display manually added cells in dynamic root mount
afs: Enable IPv6 DNS lookups
afs: Show all of a server's addresses in /proc/fs/afs/servers
afs: Handle CONFIG_PROC_FS=n
proc: Make inline name size calculation automatic
afs: Implement network namespacing
afs: Mark afs_net::ws_cell as __rcu and set using rcu functions
afs: Fix a Sparse warning in xdr_decode_AFSFetchStatus()
proc: Add a way to make network proc files writable
afs: Rearrange fs/afs/proc.c to remove remaining predeclarations.
afs: Rearrange fs/afs/proc.c to move the show routines up
afs: Rearrange fs/afs/proc.c by moving fops and open functions down
afs: Move /proc management functions to the end of the file
At the moment, afs_break_callbacks calls afs_break_one_callback() for each
separate FID it was given, and the latter looks up the volume individually
for each one.
However, this is inefficient if two or more FIDs have the same vid as we
could reuse the volume. This is complicated by cell aliasing whereby we
may have multiple cells sharing a volume and can therefore have multiple
callback interests for any particular volume ID.
At the moment afs_break_one_callback() scans the entire list of volumes
we're getting from a server and breaks the appropriate callback in every
matching volume, regardless of cell. This scan is done for every FID.
Optimise callback breaking by the following means:
(1) Sort the FID list by vid so that all FIDs belonging to the same volume
are clumped together.
This is done through the use of an indirection table as we cannot do
an insertion sort on the afs_callback_break array as we decode FIDs
into it as we subsequently also have to decode callback info into it
that corresponds by array index only.
We also don't really want to bubblesort afterwards if we can avoid it.
(2) Sort the server->cb_interests array by vid so that all the matching
volumes are grouped together. This permits the scan to stop after
finding a record that has a higher vid.
(3) When breaking FIDs, we try to keep server->cb_break_lock as long as
possible, caching the start point in the array for that volume group
as long as possible.
It might make sense to add another layer in that list and have a
refcounted volume ID anchor that has the matching interests attached
to it rather than being in the list. This would allow the lock to be
dropped without losing the cursor.
Signed-off-by: David Howells <dhowells@redhat.com>
Alter the dynroot mount so that cells created by manipulation of
/proc/fs/afs/cells and /proc/fs/afs/rootcell and by specification of a root
cell as a module parameter will cause directories for those cells to be
created in the dynamic root superblock for the network namespace[*].
To this end:
(1) Only one dynamic root superblock is now created per network namespace
and this is shared between all attempts to mount it. This makes it
easier to find the superblock to modify.
(2) When a dynamic root superblock is created, the list of cells is walked
and directories created for each cell already defined.
(3) When a new cell is added, if a dynamic root superblock exists, a
directory is created for it.
(4) When a cell is destroyed, the directory is removed.
(5) These directories are created by calling lookup_one_len() on the root
dir which automatically creates them if they don't exist.
[*] Inasmuch as network namespaces are currently supported here.
Signed-off-by: David Howells <dhowells@redhat.com>
Show all of a server's addresses in /proc/fs/afs/servers, placing the
second plus addresses on padded lines of their own. The current address is
marked with a star.
Signed-off-by: David Howells <dhowells@redhat.com>
The AFS filesystem depends at the moment on /proc for configuration and
also presents information that way - however, this causes a compilation
failure if procfs is disabled.
Fix it so that the procfs bits aren't compiled in if procfs is disabled.
This means that you can't configure the AFS filesystem directly, but it is
still usable provided that an up-to-date keyutils is installed to look up
cells by SRV or AFSDB DNS records.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
This is a late set of changes from Deepa Dinamani doing an automated
treewide conversion of the inode and iattr structures from 'timespec'
to 'timespec64', to push the conversion from the VFS layer into the
individual file systems.
There were no conflicts between this and the contents of linux-next
until just before the merge window, when we saw multiple problems:
- A minor conflict with my own y2038 fixes, which I could address
by adding another patch on top here.
- One semantic conflict with late changes to the NFS tree. I addressed
this by merging Deepa's original branch on top of the changes that
now got merged into mainline and making sure the merge commit includes
the necessary changes as produced by coccinelle.
- A trivial conflict against the removal of staging/lustre.
- Multiple conflicts against the VFS changes in the overlayfs tree.
These are still part of linux-next, but apparently this is no longer
intended for 4.18 [1], so I am ignoring that part.
As Deepa writes:
The series aims to switch vfs timestamps to use struct timespec64.
Currently vfs uses struct timespec, which is not y2038 safe.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64 timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual
replacement becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions.
Thomas Gleixner adds:
I think there is no point to drag that out for the next merge window.
The whole thing needs to be done in one go for the core changes which
means that you're going to play that catchup game forever. Let's get
over with it towards the end of the merge window.
[1] https://www.spinics.net/lists/linux-fsdevel/msg128294.html
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Merge tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground
Pull inode timestamps conversion to timespec64 from Arnd Bergmann:
"This is a late set of changes from Deepa Dinamani doing an automated
treewide conversion of the inode and iattr structures from 'timespec'
to 'timespec64', to push the conversion from the VFS layer into the
individual file systems.
As Deepa writes:
'The series aims to switch vfs timestamps to use struct timespec64.
Currently vfs uses struct timespec, which is not y2038 safe.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64
timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual replacement
becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions'
Thomas Gleixner adds:
'I think there is no point to drag that out for the next merge
window. The whole thing needs to be done in one go for the core
changes which means that you're going to play that catchup game
forever. Let's get over with it towards the end of the merge window'"
* tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
pstore: Remove bogus format string definition
vfs: change inode times to use struct timespec64
pstore: Convert internal records to timespec64
udf: Simplify calls to udf_disk_stamp_to_time
fs: nfs: get rid of memcpys for inode times
ceph: make inode time prints to be long long
lustre: Use long long type to print inode time
fs: add timespec64_truncate()
Pull networking updates from David Miller:
1) Add Maglev hashing scheduler to IPVS, from Inju Song.
2) Lots of new TC subsystem tests from Roman Mashak.
3) Add TCP zero copy receive and fix delayed acks and autotuning with
SO_RCVLOWAT, from Eric Dumazet.
4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
Brouer.
5) Add ttl inherit support to vxlan, from Hangbin Liu.
6) Properly separate ipv6 routes into their logically independant
components. fib6_info for the routing table, and fib6_nh for sets of
nexthops, which thus can be shared. From David Ahern.
7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
messages from XDP programs. From Nikita V. Shirokov.
8) Lots of long overdue cleanups to the r8169 driver, from Heiner
Kallweit.
9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.
10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.
11) Plumb extack down into fib_rules, from Roopa Prabhu.
12) Add Flower classifier offload support to igb, from Vinicius Costa
Gomes.
13) Add UDP GSO support, from Willem de Bruijn.
14) Add documentation for eBPF helpers, from Quentin Monnet.
15) Add TLS tx offload to mlx5, from Ilya Lesokhin.
16) Allow applications to be given the number of bytes available to read
on a socket via a control message returned from recvmsg(), from
Soheil Hassas Yeganeh.
17) Add x86_32 eBPF JIT compiler, from Wang YanQing.
18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
From Björn Töpel.
19) Remove indirect load support from all of the BPF JITs and handle
these operations in the verifier by translating them into native BPF
instead. From Daniel Borkmann.
20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.
21) Allow XDP programs to do lookups in the main kernel routing tables
for forwarding. From David Ahern.
22) Allow drivers to store hardware state into an ELF section of kernel
dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.
23) Various RACK and loss detection improvements in TCP, from Yuchung
Cheng.
24) Add TCP SACK compression, from Eric Dumazet.
25) Add User Mode Helper support and basic bpfilter infrastructure, from
Alexei Starovoitov.
26) Support ports and protocol values in RTM_GETROUTE, from Roopa
Prabhu.
27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
Brouer.
28) Add lots of forwarding selftests, from Petr Machata.
29) Add generic network device failover driver, from Sridhar Samudrala.
* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
strparser: Add __strp_unpause and use it in ktls.
rxrpc: Fix terminal retransmission connection ID to include the channel
net: hns3: Optimize PF CMDQ interrupt switching process
net: hns3: Fix for VF mailbox receiving unknown message
net: hns3: Fix for VF mailbox cannot receiving PF response
bnx2x: use the right constant
Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
enic: fix UDP rss bits
netdev-FAQ: clarify DaveM's position for stable backports
rtnetlink: validate attributes in do_setlink()
mlxsw: Add extack messages for port_{un, }split failures
netdevsim: Add extack error message for devlink reload
devlink: Add extack to reload and port_{un, }split operations
net: metrics: add proper netlink validation
ipmr: fix error path when ipmr_new_table fails
ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
net: hns3: remove unused hclgevf_cfg_func_mta_filter
netfilter: provide udp*_lib_lookup for nf_tproxy
qed*: Utilize FW 8.37.2.0
...
- Use overflow helpers in 2-factor allocators (Kees, Rasmus)
- Introduce overflow test module (Rasmus, Kees)
- Introduce saturating size helper functions (Matthew, Kees)
- Treewide use of struct_size() for allocators (Kees)
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Merge tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull overflow updates from Kees Cook:
"This adds the new overflow checking helpers and adds them to the
2-factor argument allocators. And this adds the saturating size
helpers and does a treewide replacement for the struct_size() usage.
Additionally this adds the overflow testing modules to make sure
everything works.
I'm still working on the treewide replacements for allocators with
"simple" multiplied arguments:
*alloc(a * b, ...) -> *alloc_array(a, b, ...)
and
*zalloc(a * b, ...) -> *calloc(a, b, ...)
as well as the more complex cases, but that's separable from this
portion of the series. I expect to have the rest sent before -rc1
closes; there are a lot of messy cases to clean up.
Summary:
- Introduce arithmetic overflow test helper functions (Rasmus)
- Use overflow helpers in 2-factor allocators (Kees, Rasmus)
- Introduce overflow test module (Rasmus, Kees)
- Introduce saturating size helper functions (Matthew, Kees)
- Treewide use of struct_size() for allocators (Kees)"
* tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
treewide: Use struct_size() for devm_kmalloc() and friends
treewide: Use struct_size() for vmalloc()-family
treewide: Use struct_size() for kmalloc()-family
device: Use overflow helpers for devm_kmalloc()
mm: Use overflow helpers in kvmalloc()
mm: Use overflow helpers in kmalloc_array*()
test_overflow: Add memory allocation overflow tests
overflow.h: Add allocation size calculation helpers
test_overflow: Report test failures
test_overflow: macrofy some more, do more tests for free
lib: add runtime test of check_*_overflow functions
compiler.h: enable builtin overflow checkers and add fallback code
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};
instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);
This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:
// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
// sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@
- alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)
// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@
- alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)
// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@
- alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)
Signed-off-by: Kees Cook <keescook@chromium.org>
Sometimes an in-progress call will stop responding on the fileserver when
the fileserver quietly cancels the call with an internally marked abort
(RX_CALL_DEAD), without sending an ABORT to the client.
This causes the client's call to eventually expire from lack of incoming
packets directed its way, which currently leads to it being cancelled
locally with ETIME. Note that it's not currently clear as to why this
happens as it's really hard to reproduce.
The rotation policy implement by kAFS, however, doesn't differentiate
between ETIME meaning we didn't get any response from the server and ETIME
meaning the call got cancelled mid-flow. The latter leads to an oops when
fetching data as the rotation partially resets the afs_read descriptor,
which can result in a cleared page pointer being dereferenced because that
page has already been filled.
Handle this by the following means:
(1) Set a flag on a call when we receive a packet for it.
(2) Store the highest packet serial number so far received for a call
(bearing in mind this may wrap).
(3) If, when the "not received anything recently" timeout expires on a
call, we've received at least one packet for a call and the connection
as a whole has received packets more recently than that call, then
cancel the call locally with ECONNRESET rather than ETIME.
This indicates that the call was definitely in progress on the server.
(4) In kAFS, if the rotation algorithm sees ECONNRESET rather than ETIME,
don't try the next server, but rather abort the call.
This avoids the oops as we don't try to reuse the afs_read struct.
Rather, as-yet ungotten pages will be reread at a later data.
Also:
(5) Add an rxrpc tracepoint to log detection of the call being reset.
Without this, I occasionally see an oops like the following:
general protection fault: 0000 [#1] SMP PTI
...
RIP: 0010:_copy_to_iter+0x204/0x310
RSP: 0018:ffff8800cae0f828 EFLAGS: 00010206
RAX: 0000000000000560 RBX: 0000000000000560 RCX: 0000000000000560
RDX: ffff8800cae0f968 RSI: ffff8800d58b3312 RDI: 0005080000000000
RBP: ffff8800cae0f968 R08: 0000000000000560 R09: ffff8800ca00f400
R10: ffff8800c36f28d4 R11: 00000000000008c4 R12: ffff8800cae0f958
R13: 0000000000000560 R14: ffff8800d58b3312 R15: 0000000000000560
FS: 00007fdaef108080(0000) GS:ffff8800ca680000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb28a8fa000 CR3: 00000000d2a76002 CR4: 00000000001606e0
Call Trace:
skb_copy_datagram_iter+0x14e/0x289
rxrpc_recvmsg_data.isra.0+0x6f3/0xf68
? trace_buffer_unlock_commit_regs+0x4f/0x89
rxrpc_kernel_recv_data+0x149/0x421
afs_extract_data+0x1e0/0x798
? afs_wait_for_call_to_complete+0xc9/0x52e
afs_deliver_fs_fetch_data+0x33a/0x5ab
afs_deliver_to_call+0x1ee/0x5e0
? afs_wait_for_call_to_complete+0xc9/0x52e
afs_wait_for_call_to_complete+0x12b/0x52e
? wake_up_q+0x54/0x54
afs_make_call+0x287/0x462
? afs_fs_fetch_data+0x3e6/0x3ed
? rcu_read_lock_sched_held+0x5d/0x63
afs_fs_fetch_data+0x3e6/0x3ed
afs_fetch_data+0xbb/0x14a
afs_readpages+0x317/0x40d
__do_page_cache_readahead+0x203/0x2ba
? ondemand_readahead+0x3a7/0x3c1
ondemand_readahead+0x3a7/0x3c1
generic_file_buffered_read+0x18b/0x62f
__vfs_read+0xdb/0xfe
vfs_read+0xb2/0x137
ksys_read+0x50/0x8c
do_syscall_64+0x7d/0x1a0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Note the weird value in RDI which is a result of trying to kmap() a NULL
page pointer.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'afs-fixes-20180514' into afs-proc
backmerge AFS fixes that went into mainline and deal with
the conflict in fs/afs/fsclient.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Implement network namespacing within AFS, but don't yet let mounts occur
outside the init namespace. An additional patch will be required propagate
the network namespace across automounts.
Signed-off-by: David Howells <dhowells@redhat.com>
The afs_net::ws_cell member is sometimes used under RCU conditions from
within an seq-readlock. It isn't, however, marked __rcu and it isn't set
using the proper RCU barrier-imposing functions.
Fix this by annotating it with __rcu and using appropriate barriers to
make sure accesses are correctly ordered.
Without this, the code can produce the following warning:
>> fs/afs/proc.c:151:24: sparse: incompatible types in comparison expression (different address spaces)
Fixes: f044c8847b ("afs: Lay the groundwork for supporting network namespaces")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Sparse doesn't appear able to handle the conditionally-taken locks in
xdr_decode_AFSFetchStatus(), even though the lock and unlock are both
contingent on the same unvarying function argument.
Deal with this by interpolating a wrapper function that takes the lock if
needed and calls xdr_decode_AFSFetchStatus() on two separate branches, one
with the lock held and one without.
This allows Sparse to work out the locking.
Signed-off-by: David Howells <dhowells@redhat.com>
Rearrange fs/afs/proc.c to move the show routines up to the top of each
block so the order is show, iteration, ops, file ops, fops.
Signed-off-by: David Howells <dhowells@redhat.com>
In fs/afs/proc.c, move functions that create and remove /proc files to the
end of the source file as a first stage in getting rid of all the forward
declarations.
Signed-off-by: David Howells <dhowells@redhat.com>
In theory the AFS_VLSF_BACKVOL flag for a server in a vldb entry
would indicate the presence of a backup volume on that server.
In practice however, this flag is never set, and the presence of
a backup volume is implied by the entry having AFS_VLF_BACKEXISTS set,
for the server that hosts the read-write volume (has AFS_VLSF_RWVOL).
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Doing faccessat("/afs/some/directory", 0) triggers a BUG in the permissions
check code.
Fix this by just removing the BUG section. If no permissions are asked
for, just return okay if the file exists.
Also:
(1) Split up the directory check so that it has separate if-statements
rather than if-else-if (e.g. checking for MAY_EXEC shouldn't skip the
check for MAY_READ and MAY_WRITE).
(2) Check for MAY_CHDIR as MAY_EXEC.
Without the main fix, the following BUG may occur:
kernel BUG at fs/afs/security.c:386!
invalid opcode: 0000 [#1] SMP PTI
...
RIP: 0010:afs_permission+0x19d/0x1a0 [kafs]
...
Call Trace:
? inode_permission+0xbe/0x180
? do_faccessat+0xdc/0x270
? do_syscall_64+0x60/0x1f0
? entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fixes: 00d3b7a453 ("[AFS]: Add security support.")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Use remove_proc_subtree to remove the whole subtree on cleanup, and
unwind the registration loop into individual calls. Switch to use
proc_create_seq where applicable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Some AFS servers refuse to accept unencrypted traffic, so can't be accessed
with kAFS. Set the AF_RXRPC security level to encrypt client calls to deal
with this.
Note that incoming service calls are set by the remote client and so aren't
affected by this.
This requires an AF_RXRPC patch to pass the value set by setsockopt to calls
begun by the kernel.
Signed-off-by: David Howells <dhowells@redhat.com>
The handling of CB.CallBack messages sent by the fileserver to the client
is broken in that they are currently being processed after the reply has
been transmitted.
This is not what the fileserver expects, however. It holds up change
visibility until the reply comes so as to maintain cache coherency, and so
expects the client to have to refetch the state on the affected files.
Fix CB.CallBack handling to perform the callback break before sending the
reply.
The fileserver is free to hold up status fetches issued by other threads on
the same client that occur in reponse to the callback until any pending
changes have been committed.
Fixes: d001648ec7 ("rxrpc: Don't expose skbs to in-kernel users [ver #2]")
Signed-off-by: David Howells <dhowells@redhat.com>
It's possible for an AFS file server to issue a whole-volume notification
that callbacks on all the vnodes in the file have been broken. This is
done for R/O and backup volumes (which don't have per-file callbacks) and
for things like a volume being taken offline.
Fix callback handling to detect whole-volume notifications, to track it
across operations and to check it during inode validation.
Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
The code that looks up servers by addresses makes the assumption
that the list of addresses for a server is sorted. It exits the
loop if it finds that the target address is larger than the
current candidate. As the list is not currently sorted, this
can lead to a failure to find a matching server, which can cause
callbacks from that server to be ignored.
Remove the early exit case so that the complete list is searched.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
If the client cache manager operations that need the server record
(CB.Callback, CB.InitCallBackState, and CB.InitCallBackState3) can't find
the server record, they abort the call from the file server with
RX_CALL_DEAD when they should return okay.
Fixes: c35eccb1f6 ("[AFS]: Implement the CB.InitCallBackState3 operation.")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the handling of the CB.InitCallBackState3 service call to find the
record of a server that we're using by looking it up by the UUID passed as
the parameter rather than by its address (of which it might have many, and
which may change).
Fixes: c35eccb1f6 ("[AFS]: Implement the CB.InitCallBackState3 operation.")
Signed-off-by: David Howells <dhowells@redhat.com>
If a volume location record lists multiple file servers for a volume, then
it's possible that due to a misconfiguration or a changing configuration
that one of the file servers doesn't know about it yet and will abort
VNOVOL. Currently, the rotation algorithm will stop with EREMOTEIO.
Fix this by moving on to try the next server if VNOVOL is returned. Once
all the servers have been tried and the record rechecked, the algorithm
will stop with EREMOTEIO or ENOMEDIUM.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
The OpenAFS server's RXAFS_InlineBulkStatus implementation has a bug
whereby if an error occurs on one of the vnodes being queried, then the
errorCode field is set correctly in the corresponding status, but the
interfaceVersion field is left unset.
Fix kAFS to deal with this by evaluating the AFSFetchStatus blob against
the following cases when called from FS.InlineBulkStatus delivery:
(1) If InterfaceVersion == 0 then:
(a) If errorCode != 0 then it indicates the abort code for the
corresponding vnode.
(b) If errorCode == 0 then the status record is invalid.
(2) If InterfaceVersion == 1 then:
(a) If errorCode != 0 then it indicates the abort code for the
corresponding vnode.
(b) If errorCode == 0 then the status record is valid and can be
parsed.
(3) If InterfaceVersion is anything else then the status record is
invalid.
Fixes: dd9fbcb8e1 ("afs: Rearrange status mapping")
Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
The server rotation algorithm just gives up if it fails to probe a
fileserver. Fix this by rotating to the next fileserver instead.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
The refcounting on afs_cb_interest struct objects in
afs_register_server_cb_interest() is wrong as it uses the server list
entry's call back interest pointer without regard for the fact that it
might be replaced at any time and the object thrown away.
Fix this by:
(1) Put a lock on the afs_server_list struct that can be used to
mediate access to the callback interest pointers in the servers array.
(2) Keep a ref on the callback interest that we get from the entry.
(3) Dropping the old reference held by vnode->cb_interest if we replace
the pointer.
Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
When a server record is destroyed, we want to send a message to the server
telling it that we're giving up all the callbacks it has promised us.
Apply two fixes to this:
(1) Only send the FS.GiveUpAllCallBacks message if we actually got a
callback from that server. We assume this to be the case if we
performed at least one successful FS operation on that server.
(2) Send it to the address last used for that server rather than always
picking the first address in the list (which might be unreachable).
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
The parsing of port specifiers in the address list obtained from the DNS
resolution upcall doesn't work as in4_pton() and in6_pton() will fail on
encountering an unexpected delimiter (in this case, the '+' marking the
port number). However, in*_pton() can't be given multiple specifiers.
Fix this by finding the delimiter in advance and not relying on in*_pton()
to find the end of the address for us.
Fixes: 8b2a464ced ("afs: Add an address list concept")
Signed-off-by: David Howells <dhowells@redhat.com>
The afs directory loading code (primarily afs_read_dir()) locks all the
pages that hold a directory's content blob to defend against
getdents/getdents races and getdents/lookup races where the competitors
issue conflicting reads on the same data. As the reads will complete
consecutively, they may retrieve different versions of the data and
one may overwrite the data that the other is busy parsing.
Fix this by not locking the pages at all, but rather by turning the
validation lock into an rwsem and getting an exclusive lock on it whilst
reading the data or validating the attributes and a shared lock whilst
parsing the data. Sharing the attribute validation lock should be fine as
the data fetch will retrieve the attributes also.
The individual page locks aren't needed at all as the only place they're
being used is to serialise data loading.
Without this patch, the:
if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
...
}
part of afs_read_dir() may be skipped, leaving the pages unlocked when we
hit the success: clause - in which case we try to unlock the not-locked
pages, leading to the following oops:
page:ffffe38b405b4300 count:3 mapcount:0 mapping:ffff98156c83a978 index:0x0
flags: 0xfffe000001004(referenced|private)
raw: 000fffe000001004 ffff98156c83a978 0000000000000000 00000003ffffffff
raw: dead000000000100 dead000000000200 0000000000000001 ffff98156b27c000
page dumped because: VM_BUG_ON_PAGE(!PageLocked(page))
page->mem_cgroup:ffff98156b27c000
------------[ cut here ]------------
kernel BUG at mm/filemap.c:1205!
...
RIP: 0010:unlock_page+0x43/0x50
...
Call Trace:
afs_dir_iterate+0x789/0x8f0 [kafs]
? _cond_resched+0x15/0x30
? kmem_cache_alloc_trace+0x166/0x1d0
? afs_do_lookup+0x69/0x490 [kafs]
? afs_do_lookup+0x101/0x490 [kafs]
? key_default_cmp+0x20/0x20
? request_key+0x3c/0x80
? afs_lookup+0xf1/0x340 [kafs]
? __lookup_slow+0x97/0x150
? lookup_slow+0x35/0x50
? walk_component+0x1bf/0x490
? path_lookupat.isra.52+0x75/0x200
? filename_lookup.part.66+0xa0/0x170
? afs_end_vnode_operation+0x41/0x60 [kafs]
? __check_object_size+0x9c/0x171
? strncpy_from_user+0x4a/0x170
? vfs_statx+0x73/0xe0
? __do_sys_newlstat+0x39/0x70
? __x64_sys_getdents+0xc9/0x140
? __x64_sys_getdents+0x140/0x140
? do_syscall_64+0x5b/0x160
? entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: f3ddee8dc4 ("afs: Fix directory handling")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
AFS server records get removed from the net->fs_servers tree when
they're deleted, but not from the net->fs_addresses{4,6} lists, which
can lead to an oops in afs_find_server() when a server record has been
removed, for instance during rmmod.
Fix this by deleting the record from the by-address lists before posting
it for RCU destruction.
The reason this hasn't been noticed before is that the fileserver keeps
probing the local cache manager, thereby keeping the service record
alive, so the oops would only happen when a fileserver eventually gets
bored and stops pinging or if the module gets rmmod'd and a call comes
in from the fileserver during the window between the server records
being destroyed and the socket being closed.
The oops looks something like:
BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
...
Workqueue: kafsd afs_process_async_call [kafs]
RIP: 0010:afs_find_server+0x271/0x36f [kafs]
...
Call Trace:
afs_deliver_cb_init_call_back_state3+0x1f2/0x21f [kafs]
afs_deliver_to_call+0x1ee/0x5e8 [kafs]
afs_process_async_call+0x5b/0xd0 [kafs]
process_one_work+0x2c2/0x504
worker_thread+0x1d4/0x2ac
kthread+0x11f/0x127
ret_from_fork+0x24/0x30
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull AFS updates from Al Viro:
"The AFS series posted by dhowells depended upon lookup_one_len()
rework; now that prereq is in the mainline, that series had been
rebased on top of it and got some exposure and testing..."
* 'afs-dh' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
afs: Do better accretion of small writes on newly created content
afs: Add stats for data transfer operations
afs: Trace protocol errors
afs: Locally edit directory data for mkdir/create/unlink/...
afs: Adjust the directory XDR structures
afs: Split the directory content defs into a header
afs: Fix directory handling
afs: Split the dynroot stuff out and give it its own ops tables
afs: Keep track of invalid-before version for dentry coherency
afs: Rearrange status mapping
afs: Make it possible to get the data version in readpage
afs: Init inode before accessing cache
afs: Introduce a statistics proc file
afs: Dump bad status record
afs: Implement @cell substitution handling
afs: Implement @sys substitution handling
afs: Prospectively look up extra files when doing a single lookup
afs: Don't over-increment the cell usage count when pinning it
afs: Fix checker warnings
vfs: Remove the const from dir_context::actor
Remove the address_space ->tree_lock and use the xa_lock newly added to
the radix_tree_root. Rename the address_space ->page_tree to ->i_pages,
since we don't really care that it's a tree.
[willy@infradead.org: fix nds32, fs/dax.c]
Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Processes like ld that do lots of small writes that aren't necessarily
contiguous result in a lot of small StoreData operations to the server, the
idea being that if someone else changes the data on the server, we only
write our changes over that and not the space between. Further, we don't
want to write back empty space if we can avoid it to make it easier for the
server to do sparse files.
However, making lots of tiny RPC ops is a lot less efficient for the server
than one big one because each op requires allocation of resources and the
taking of locks, so we want to compromise a bit.
Reduce the load by the following:
(1) If a file is just created locally or has just been truncated with
O_TRUNC locally, allow subsequent writes to the file to be merged with
intervening space if that space doesn't cross an entire intervening
page.
(2) Don't flush the file on ->flush() but rather on ->release() if the
file was open for writing.
Just linking vmlinux.o, without this patch, looking in /proc/fs/afs/stats:
file-wr : n=441 nb=513581204
and after the patch:
file-wr : n=62 nb=513668555
there were 379 fewer StoreData RPC operations at the expense of an extra
87K being written.
Signed-off-by: David Howells <dhowells@redhat.com>
Add statistics to /proc/fs/afs/stats for data transfer RPC operations. New
lines are added that look like:
file-rd : n=55794 nb=10252282150
file-wr : n=9789 nb=3247763645
where n= indicates the number of ops completed and nb= indicates the number
of bytes successfully transferred. file-rd is the counts for read/fetch
operations and file-wr the counts for write/store operations.
Note that directory and symlink downloading are included in the file-rd
stats at the moment.
Signed-off-by: David Howells <dhowells@redhat.com>
Locally edit the contents of an AFS directory upon a successful inode
operation that modifies that directory (such as mkdir, create and unlink)
so that we can avoid the current practice of re-downloading the directory
after each change.
This is viable provided that the directory version number we get back from
the modifying RPC op is exactly incremented by 1 from what we had
previously. The data in the directory contents is in a defined format that
we have to parse locally to perform lookups and readdir, so modifying isn't
a problem.
If the edit fails, we just clear the VALID flag on the directory and it
will be reloaded next time it is needed.
Signed-off-by: David Howells <dhowells@redhat.com>
Adjust the AFS directory XDR structures in a number of superficial ways:
(1) Rename them to all begin afs_xdr_.
(2) Use u8 instead of uint8_t.
(3) Mark the structures as __packed so they don't get rearranged by the
compiler.
(4) Rename the hdr member of afs_xdr_dir_block to meta.
(5) Rename the pagehdr member of afs_xdr_dir_block to hdr.
Signed-off-by: David Howells <dhowells@redhat.com>
Split the directory content definitions into a header file so that they can
be used by multiple .c files.
Signed-off-by: David Howells <dhowells@redhat.com>
AFS directories are structured blobs that are downloaded just like files
and then parsed by the lookup and readdir code and, as such, are currently
handled in the pagecache like any other file, with the entire directory
content being thrown away each time the directory changes.
However, since the blob is a known structure and since the data version
counter on a directory increases by exactly one for each change committed
to that directory, we can actually edit the directory locally rather than
fetching it from the server after each locally-induced change.
What we can't do, though, is mix data from the server and data from the
client since the server is technically at liberty to rearrange or compress
a directory if it sees fit, provided it updates the data version number
when it does so and breaks the callback (ie. sends a notification).
Further, lookup with lookup-ahead, readdir and, when it arrives, local
editing are likely want to scan the whole of a directory.
So directory handling needs to be improved to maintain the coherency of the
directory blob prior to permitting local directory editing.
To this end:
(1) If any directory page gets discarded, invalidate and reread the entire
directory.
(2) If readpage notes that if when it fetches a single page that the
version number has changed, the entire directory is flagged for
invalidation.
(3) Read as much of the directory in one go as we can.
Note that this removes local caching of directories in fscache for the
moment as we can't pass the pages to fscache_read_or_alloc_pages() since
page->lru is in use by the LRU.
Signed-off-by: David Howells <dhowells@redhat.com>
Split the AFS dynamic root stuff out of the main directory handling file
and into its own file as they share little in common.
The dynamic root code also gets its own dentry and inode ops tables.
Signed-off-by: David Howells <dhowells@redhat.com>
Each afs dentry is tagged with the version that the parent directory was at
last time it was validated and, currently, if this differs, the directory
is scanned and the dentry is refreshed.
However, this leads to an excessive amount of revalidation on directories
that get modified on the client without conflict with another client. We
know there's no conflict because the parent directory's data version number
got incremented by exactly 1 on any create, mkdir, unlink, etc., therefore
we can trust the current state of the unaffected dentries when we perform a
local directory modification.
Optimise by keeping track of the last version of the parent directory that
was changed outside of the client in the parent directory's vnode and using
that to validate the dentries rather than the current version.
Signed-off-by: David Howells <dhowells@redhat.com>
Rearrange the AFSFetchStatus to inode attribute mapping code in a number of
ways:
(1) Use an XDR structure rather than a series of incremented pointer
accesses when decoding an AFSFetchStatus object. This allows
out-of-order decode.
(2) Don't store the if_version value but rather just check it and abort if
it's not something we can handle.
(3) Store the owner and group in the status record as raw values rather
than converting them to kuid/kgid. Do that when they're mapped into
i_uid/i_gid.
(4) Validate the type and abort code up front and abort if they're wrong.
(5) Split the inode attribute setting out into its own function from the
XDR decode of an AFSFetchStatus object. This allows it to be called
from elsewhere too.
(6) Differentiate changes to data from changes to metadata.
(7) Use the split-out attribute mapping function from afs_iget().
Signed-off-by: David Howells <dhowells@redhat.com>
Store the data version number indicated by an FS.FetchData op into the read
request structure so that it's accessible by the page reader.
Signed-off-by: David Howells <dhowells@redhat.com>
We no longer parse symlinks when we get the inode to determine if this
symlink is actually a mountpoint as we detect that by examining the mode
instead (symlinks are always 0777 and mountpoints 0644).
Access the cache after mapping the status so that we don't have to manually
set the inode size now.
Note that this may need adjusting if the disconnected operation is
implemented as the file metadata may have to be obtained from the cache.
Signed-off-by: David Howells <dhowells@redhat.com>
Introduce a proc file that displays a bunch of statistics for the AFS
filesystem in the current network namespace.
Signed-off-by: David Howells <dhowells@redhat.com>
Implement @cell substitution handling such that if @cell is seen as a name
in a dynamic root mount, then the name of the root cell for that network
namespace will be substituted for @cell during lookup.
The substitution of @cell for the current net namespace is set by writing
the cell name to /proc/fs/afs/rootcell. The value can be obtained by
reading the file.
For example:
# mount -t afs none /kafs -o dyn
# echo grand.central.org >/proc/fs/afs/rootcell
# ls /kafs/@cell
archive/ cvs/ doc/ local/ project/ service/ software/ user/ www/
# cat /proc/fs/afs/rootcell
grand.central.org
Signed-off-by: David Howells <dhowells@redhat.com>
Implement the AFS feature by which @sys at the end of a pathname component
may be substituted for one of a list of values, typically naming the
operating system. Up to 16 alternatives may be specified and these are
tried in turn until one works. Each network namespace has[*] a separate
independent list.
Upon creation of a new network namespace, the list of values is
initialised[*] to a single OpenAFS-compatible string representing arch type
plus "_linux26". For example, on x86_64, the sysname is "amd64_linux26".
[*] Or will, once network namespace support is finalised in kAFS.
The list may be set by:
# for i in foo bar linux-x86_64; do echo $i; done >/proc/fs/afs/sysname
for which separate writes to the same fd are amalgamated and applied on
close. The LF character may be used as a separator to specify multiple
items in the same write() call.
The list may be cleared by:
# echo >/proc/fs/afs/sysname
and read by:
# cat /proc/fs/afs/sysname
foo
bar
linux-x86_64
Signed-off-by: David Howells <dhowells@redhat.com>
When afs_lookup() is called, prospectively look up the next 50 uncached
fids also from that same directory and cache the results, rather than just
looking up the one file requested.
This allows us to use the FS.InlineBulkStatus RPC op to increase efficiency
by fetching up to 50 file statuses at a time.
Signed-off-by: David Howells <dhowells@redhat.com>
AFS cells that are added or set as the workstation cell through /proc are
pinned against removal by setting the AFS_CELL_FL_NO_GC flag on them and
taking a ref. The ref should be only taken if the flag wasn't already set.
Fix this by making it conditional.
Without this an assertion failure will occur during module removal
indicating that the refcount is too elevated.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix warnings raised by checker, including:
(*) Warnings raised by unequal comparison for the purposes of sorting,
where the endianness doesn't matter:
fs/afs/addr_list.c:246:21: warning: restricted __be16 degrades to integer
fs/afs/addr_list.c:246:30: warning: restricted __be16 degrades to integer
fs/afs/addr_list.c:248:21: warning: restricted __be32 degrades to integer
fs/afs/addr_list.c:248:49: warning: restricted __be32 degrades to integer
fs/afs/addr_list.c:283:21: warning: restricted __be16 degrades to integer
fs/afs/addr_list.c:283:30: warning: restricted __be16 degrades to integer
(*) afs_set_cb_interest() is not actually used and can be removed.
(*) afs_cell_gc_delay() should be provided with a sysctl.
(*) afs_cell_destroy() needs to use rcu_access_pointer() to read
cell->vl_addrs.
(*) afs_init_fs_cursor() should be static.
(*) struct afs_vnode::permit_cache needs to be marked __rcu.
(*) afs_server_rcu() needs to use rcu_access_pointer().
(*) afs_destroy_server() should use rcu_access_pointer() on
server->addresses as the server object is no longer accessible.
(*) afs_find_server() casts __be16/__be32 values to int in order to
directly compare them for the purpose of finding a match in a list,
but is should also annotate the cast with __force to avoid checker
warnings.
(*) afs_check_permit() accesses vnode->permit_cache outside of the RCU
readlock, though it doesn't then access the value; the extraneous
access is deleted.
False positives:
(*) Conditional locking around the code in xdr_decode_AFSFetchStatus. This
can be dealt with in a separate patch.
fs/afs/fsclient.c:148:9: warning: context imbalance in 'xdr_decode_AFSFetchStatus' - different lock contexts for basic block
(*) Incorrect handling of seq-retry lock context balance:
fs/afs/inode.c:455:38: warning: context imbalance in 'afs_getattr' - different
lock contexts for basic block
fs/afs/server.c:52:17: warning: context imbalance in 'afs_find_server' - different lock contexts for basic block
fs/afs/server.c:128:17: warning: context imbalance in 'afs_find_server_by_uuid' - different lock contexts for basic block
Errors:
(*) afs_lookup_cell_rcu() needs to break out of the seq-retry loop, not go
round again if it successfully found the workstation cell.
(*) Fix UUID decode in afs_deliver_cb_probe_uuid().
(*) afs_cache_permit() has a missing rcu_read_unlock() before one of the
jumps to the someone_else_changed_it label. Move the unlock to after
the label.
(*) afs_vl_get_addrs_u() is using ntohl() rather than htonl() when
encoding to XDR.
(*) afs_deliver_yfsvl_get_endpoints() is using htonl() rather than ntohl()
when decoding from XDR.
Signed-off-by: David Howells <dhowells@redhat.com>
Pass the object size in to fscache_acquire_cookie() and
fscache_write_page() rather than the netfs providing a callback by which it
can be received. This makes it easier to update the size of the object
when a new page is written that extends the object.
The current object size is also passed by fscache to the check_aux
function, obviating the need to store it in the aux data.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
Attach copies of the index key and auxiliary data to the fscache cookie so
that:
(1) The callbacks to the netfs for this stuff can be eliminated. This
can simplify things in the cache as the information is still
available, even after the cache has relinquished the cookie.
(2) Simplifies the locking requirements of accessing the information as we
don't have to worry about the netfs object going away on us.
(3) The cache can do lazy updating of the coherency information on disk.
As long as the cache is flushed before reboot/poweroff, there's no
need to update the coherency info on disk every time it changes.
(4) Cookies can be hashed or put in a tree as the index key is easily
available. This allows:
(a) Checks for duplicate cookies can be made at the top fscache layer
rather than down in the bowels of the cache backend.
(b) Caching can be added to a netfs object that has a cookie if the
cache is brought online after the netfs object is allocated.
A certain amount of space is made in the cookie for inline copies of the
data, but if it won't fit there, extra memory will be allocated for it.
The downside of this is that live cache operation requires more memory.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
When relinquishing cookies, either due to iget failure or to inode
eviction, retire a cookie if we think the corresponding vnode got deleted
on the server rather than just letting it lie in the cache.
Signed-off-by: David Howells <dhowells@redhat.com>
AFS vnodes (files) are referenced by a triplet of { volume ID, vnode ID,
uniquifier }. Currently, kafs is only using the vnode ID as the file key
in the volume fscache index and checking the uniquifier on cookie
acquisition against the contents of the auxiliary data stored in the cache.
Unfortunately, this is subject to a race in which an FS.RemoveFile or
FS.RemoveDir op is issued against the server but the local afs inode isn't
torn down and disposed off before another thread issues something like
FS.CreateFile. The latter then gets given the vnode ID that just got
removed, but with a new uniquifier and a cookie collision occurs in the
cache because the cookie is only keyed on the vnode ID whereas the inode is
keyed on the vnode ID plus the uniquifier.
Fix this by keying the cookie on the uniquifier in addition to the vnode ID
and dropping the uniquifier from the auxiliary data supplied.
Signed-off-by: David Howells <dhowells@redhat.com>
Invalidate any data stored in fscache for a vnode that changes on the
server so that we don't end up with the cache in a bad state locally.
Signed-off-by: David Howells <dhowells@redhat.com>
Pull networking updates from David Miller:
1) Support offloading wireless authentication to userspace via
NL80211_CMD_EXTERNAL_AUTH, from Srinivas Dasari.
2) A lot of work on network namespace setup/teardown from Kirill Tkhai.
Setup and cleanup of namespaces now all run asynchronously and thus
performance is significantly increased.
3) Add rx/tx timestamping support to mv88e6xxx driver, from Brandon
Streiff.
4) Support zerocopy on RDS sockets, from Sowmini Varadhan.
5) Use denser instruction encoding in x86 eBPF JIT, from Daniel
Borkmann.
6) Support hw offload of vlan filtering in mvpp2 dreiver, from Maxime
Chevallier.
7) Support grafting of child qdiscs in mlxsw driver, from Nogah
Frankel.
8) Add packet forwarding tests to selftests, from Ido Schimmel.
9) Deal with sub-optimal GSO packets better in BBR congestion control,
from Eric Dumazet.
10) Support 5-tuple hashing in ipv6 multipath routing, from David Ahern.
11) Add path MTU tests to selftests, from Stefano Brivio.
12) Various bits of IPSEC offloading support for mlx5, from Aviad
Yehezkel, Yossi Kuperman, and Saeed Mahameed.
13) Support RSS spreading on ntuple filters in SFC driver, from Edward
Cree.
14) Lots of sockmap work from John Fastabend. Applications can use eBPF
to filter sendmsg and sendpage operations.
15) In-kernel receive TLS support, from Dave Watson.
16) Add XDP support to ixgbevf, this is significant because it should
allow optimized XDP usage in various cloud environments. From Tony
Nguyen.
17) Add new Intel E800 series "ice" ethernet driver, from Anirudh
Venkataramanan et al.
18) IP fragmentation match offload support in nfp driver, from Pieter
Jansen van Vuuren.
19) Support XDP redirect in i40e driver, from Björn Töpel.
20) Add BPF_RAW_TRACEPOINT program type for accessing the arguments of
tracepoints in their raw form, from Alexei Starovoitov.
21) Lots of striding RQ improvements to mlx5 driver with many
performance improvements, from Tariq Toukan.
22) Use rhashtable for inet frag reassembly, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1678 commits)
net: mvneta: improve suspend/resume
net: mvneta: split rxq/txq init and txq deinit into SW and HW parts
ipv6: frags: fix /proc/sys/net/ipv6/ip6frag_low_thresh
net: bgmac: Fix endian access in bgmac_dma_tx_ring_free()
net: bgmac: Correctly annotate register space
route: check sysctl_fib_multipath_use_neigh earlier than hash
fix typo in command value in drivers/net/phy/mdio-bitbang.
sky2: Increase D3 delay to sky2 stops working after suspend
net/mlx5e: Set EQE based as default TX interrupt moderation mode
ibmvnic: Disable irqs before exiting reset from closed state
net: sched: do not emit messages while holding spinlock
vlan: also check phy_driver ts_info for vlan's real device
Bluetooth: Mark expected switch fall-throughs
Bluetooth: Set HCI_QUIRK_SIMULTANEOUS_DISCOVERY for BTUSB_QCA_ROME
Bluetooth: btrsi: remove unused including <linux/version.h>
Bluetooth: hci_bcm: Remove DMI quirk for the MINIX Z83-4
sh_eth: kill useless check in __sh_eth_get_regs()
sh_eth: add sh_eth_cpu_data::no_xdfar flag
ipv6: factorize sk_wmem_alloc updates done by __ip6_append_data()
ipv4: factorize sk_wmem_alloc updates done by __ip_append_data()
...
In rxrpc and afs, use the debug_ids that are monotonically allocated to
various objects as they're allocated rather than pointers as kernel
pointers are now hashed making them less useful. Further, the debug ids
aren't reused anywhere nearly as quickly.
In addition, allow kernel services that use rxrpc, such as afs, to take
numbers from the rxrpc counter, assign them to their own call struct and
pass them in to rxrpc for both client and service calls so that the trace
lines for each will have the same ID tag.
Signed-off-by: David Howells <dhowells@redhat.com>
The old wait_on_atomic_t() is going to get removed, use the more
flexible wait_var_event() API instead.
No change in functionality.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Support the AFS dynamic root which is a pseudo-volume that doesn't connect
to any server resource, but rather is just a root directory that
dynamically creates mountpoint directories where the name of such a
directory is the name of the cell.
Such a mount can be created thus:
mount -t afs none /afs -o dyn
Dynamic root superblocks aren't shared except by bind mounts and
propagation. Cell root volumes can then be mounted by referring to them by
name, e.g.:
ls /afs/grand.central.org/
ls /afs/.grand.central.org/
The kernel will upcall to consult the DNS if the address wasn't supplied
directly.
Signed-off-by: David Howells <dhowells@redhat.com>
Rearrange afs_select_fileserver() a little to put the use_server chunk
before the next_server chunk so that with the removal of a couple of gotos
the main path through the function is all one sequence.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix server list handling in the following ways:
(1) In afs_alloc_volume(), remove duplicate server list build code. This
was already done by afs_alloc_server_list() which afs_alloc_volume()
previously called. This just results in twice as many VL RPCs.
(2) In afs_deliver_vl_get_entry_by_name_u(), use the number of server
records indicated by ->nServers in the UVLDB record returned by the
VL.GetEntryByNameU RPC call rather than scanning all NMAXNSERVERS
slots. Unused slots may contain garbage.
(3) In afs_alloc_server_list(), don't stop converting a UVLDB record into
a server list just because we can't look up one of the servers. Just
skip that server and go on to the next. If we can't look up any of
the servers then we'll fail at the end.
Without this patch, an attempt to view the umich.edu root cell using
something like "ls /afs/umich.edu" on a dynamic root (future patch) mount
or an autocell mount will result in ENOMEDIUM. The failure is due to kafs
not stopping after nServers'worth of records have been read, but then
trying to access a server with a garbage UUID and getting an error, which
aborts the server list build.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
In afs_select_fileserver(), we need to clear the ->responded flag in the
address list when reusing it. We should also clear it in
afs_select_current_fileserver().
To this end, just memset() the object before initialising it.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
afs_select_fileserver() ends the address cursor it is using in the case in
which we get some sort of network error and run out of addresses to iterate
through, before it jumps to try the next server. This also needs to be
done when the server aborts with some sort of error that means we should
try the next server.
Fix this by:
(1) Move the iterate_address afs_end_cursor() call to the next_server
case.
(2) End the cursor in the failed case.
(3) Make afs_end_cursor() clear the ->begun flag and ->addr pointer in the
address cursor.
(4) Make afs_end_cursor() able to be called on an already cleared cursor.
Without this, something like the following oops may occur:
AFS: Assertion failed
18446612134397189888 == 0 is false
0xffff88007c279f00 == 0x0 is false
------------[ cut here ]------------
kernel BUG at fs/afs/rotate.c:360!
RIP: 0010:afs_select_fileserver+0x79b/0xa30 [kafs]
Call Trace:
afs_statfs+0xcc/0x180 [kafs]
? p9_client_statfs+0x9e/0x110 [9pnet]
? _cond_resched+0x19/0x40
statfs_by_dentry+0x6d/0x90
vfs_statfs+0x1b/0xc0
user_statfs+0x4b/0x80
SYSC_statfs+0x15/0x30
SyS_statfs+0xe/0x10
entry_SYSCALL_64_fastpath+0x20/0x83
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
afs_alloc_volume() needs to release the cell ref it obtained in the case of
an error. Fix this by adding an afs_put_cell() call into the error path.
This can triggered when a lookup for a cell in a dynamic root or an
autocell mount returns an error whilst trying to look up the server (such
as ENOMEDIUM). This results in an assertion failure oops when the module
is unloaded due to outstanding refs on a cell record.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: stable@vger.kernel.org
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Merge tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull inode->i_version rework from Jeff Layton:
"This pile of patches is a rework of the inode->i_version field. We
have traditionally incremented that field on every inode data or
metadata change. Typically this increment needs to be logged on disk
even when nothing else has changed, which is rather expensive.
It turns out though that none of the consumers of that field actually
require this behavior. The only real requirement for all of them is
that it be different iff the inode has changed since the last time the
field was checked.
Given that, we can optimize away most of the i_version increments and
avoid dirtying inode metadata when the only change is to the i_version
and no one is querying it. Queries of the i_version field are rather
rare, so we can help write performance under many common workloads.
This patch series converts existing accesses of the i_version field to
a new API, and then converts all of the in-kernel filesystems to use
it. The last patch in the series then converts the backend
implementation to a scheme that optimizes away a large portion of the
metadata updates when no one is looking at it.
In my own testing this series significantly helps performance with
small I/O sizes. I also got this email for Christmas this year from
the kernel test robot (a 244% r/w bandwidth improvement with XFS over
DAX, with 4k writes):
https://lkml.org/lkml/2017/12/25/8
A few of the earlier patches in this pile are also flowing to you via
other trees (mm, integrity, and nfsd trees in particular)".
* tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: (22 commits)
fs: handle inode->i_version more efficiently
btrfs: only dirty the inode in btrfs_update_time if something was changed
xfs: avoid setting XFS_ILOG_CORE if i_version doesn't need incrementing
fs: only set S_VERSION when updating times if necessary
IMA: switch IMA over to new i_version API
xfs: convert to new i_version API
ufs: use new i_version API
ocfs2: convert to new i_version API
nfsd: convert to new i_version API
nfs: convert to new i_version API
ext4: convert to new i_version API
ext2: convert to new i_version API
exofs: switch to new i_version API
btrfs: convert to new i_version API
afs: convert to new i_version API
affs: convert to new i_version API
fat: convert to new i_version API
fs: don't take the i_lock in inode_inc_iversion
fs: new API for handling inode->i_version
ntfs: remove i_version handling
...
For AFS, it's generally treated as an opaque value, so we use the
*_raw variants of the API here.
Note that AFS has quite a different definition for this counter. AFS
only increments it on changes to the data to the data in regular files
and contents of the directories. Inode metadata changes do not result
in a version increment.
We'll need to reconcile that somehow if we ever want to present this to
userspace via statx.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
afs_write_end() is missing page unlock and put if afs_fill_page() fails.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Repeating creation and deletion of a file on an afs mount will run the box
out of memory, e.g.:
dd if=/dev/zero of=/afs/scratch/m0 bs=$((1024*1024)) count=512
rm /afs/scratch/m0
The problem seems to be that it's not properly decrementing the nlink count
so that the inode can be scrapped.
Note that this doesn't fix local creation followed by remote deletion.
That's harder to handle and will require a separate patch as we're not told
that the file has been deleted - only that the directory has changed.
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Smatch warns that:
fs/afs/rxrpc.c:922 afs_extract_data()
error: uninitialized symbol 'remote_abort'.
Smatch is right that "remote_abort" might be uninitialized when we pass
it to afs_set_call_complete(). I don't know if that function uses the
uninitialized variable. Anyway, the comment for rxrpc_kernel_recv_data(),
says that "*_abort should also be initialised to 0." and this patch does
that.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
When an AFS inode is allocated by afs_alloc_inode(), the allocated
afs_vnode struct isn't necessarily reset from the last time it was used as
an inode because the slab constructor is only invoked once when the memory
is obtained from the page allocator.
This means that information can leak from one inode to the next because
we're not calling kmem_cache_zalloc(). Some of the information isn't
reset, in particular the permit cache pointer.
Bring the clearances up to date.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
Fix four refcount bugs in afs_cache_permit():
(1) When checking the result of the kzalloc(), we can't just return, but
must put 'permits'.
(2) We shouldn't put permits immediately after hashing a new permit as we
need to keep the pointer stable so that we can check to see if
vnode->permit_cache has changed before we decide whether to assign to
it.
(3) 'permits' is being put twice.
(4) We need to put either the replacement or the thing replaced after the
assignment to vnode->permit_cache.
Without this, lots of the following are seen:
Kernel BUG at ffffffffa039857b [verbose debug info unavailable]
------------[ cut here ]------------
Kernel BUG at ffffffffa039858a [verbose debug info unavailable]
------------[ cut here ]------------
The addresses are in the .text..refcount section of the kafs.ko module.
Following the relocation records for the __ex_table section shows one to be
due to the decrement in afs_put_permits() and the other to be key_get() in
afs_cache_permit().
Occasionally, the following is seen:
refcount_t overflow at afs_cache_permit+0x57d/0x5c0 [kafs] in cc1[562], uid/euid: 0/0
WARNING: CPU: 0 PID: 562 at kernel/panic.c:657 refcount_error_report+0x9c/0xac
...
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
This is a pure automated search-and-replace of the internal kernel
superblock flags.
The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.
Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.
The script to do this was:
# places to look in; re security/*: it generally should *not* be
# touched (that stuff parses mount(2) arguments directly), but
# there are two places where we really deal with superblock flags.
FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
include/linux/fs.h include/uapi/linux/bfs_fs.h \
security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
# the list of MS_... constants
SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
ACTIVE NOUSER"
SED_PROG=
for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done
# we want files that contain at least one of MS_...,
# with fs/namespace.c and fs/pnode.c excluded.
L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')
for f in $L; do sed -i $f $SED_PROG; done
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The assignment of dvnode to itself is redundant and can be removed.
Cleans up warning detected by cppcheck:
fs/afs/dir.c:975: (warning) Redundant assignment of 'dvnode' to itself.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Due to recent changes this piece of code is no longer needed.
Addresses-Coverity-ID: 1462033
Link: https://lkml.kernel.org/r/4923.1510957307@warthog.procyon.org.uk
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
afs_mkdir(), afs_create(), afs_link() and afs_symlink() all need to drop
the target dentry if a signal causes the operation to be killed immediately
before we try to contact the server.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix some of dentry handling in AFS directory ops:
(1) Do d_drop() on the new_dentry before assigning a new inode to it in
afs_vnode_new_inode(). It's fine to do this before calling afs_iget()
because the operation has taken place on the server.
(2) Replace d_instantiate()/d_rehash() with d_add().
(3) Don't d_drop() the new_dentry in afs_rename() on error.
Also fix afs_link() and afs_rename() to call key_put() on all error paths
where the key is taken.
Signed-off-by: David Howells <dhowells@redhat.com>
Make afs_write_begin() wait for a page that's marked PG_writeback because:
(1) We need to avoid interference with the data being stored so that the
data on the server ends up in a defined state.
(2) page->private is used to track the window of dirty data within a page,
but it's also used by the storage code to track what's being written,
being cleared by the completion notification. Ownership can't be
relinquished by the storage code until completion because it a store
fails, the data must be remarked dirty.
Tracing shows something like the following (edited):
x86_64-linux-gn-15940 [1] afs_page_dirty: vn=ffff8800bef33800 9c75 begin 0-125
kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 store+ 0-125
x86_64-linux-gn-15940 [1] afs_page_dirty: vn=ffff8800bef33800 9c75 begin 0-2052
kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 clear 0-2052
kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 store 0-0
kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 WARN 0-0
The clear (completion) corresponding to the store+ (store continuation from
a previous page) happens between the second begin (afs_write_begin) and the
store corresponding to that. This results in the second store not seeing
any data to write back, leading to the following warning:
WARNING: CPU: 2 PID: 114 at ../fs/afs/write.c:403 afs_write_back_from_locked_page+0x19d/0x76c [kafs]
Modules linked in: kafs(E)
CPU: 2 PID: 114 Comm: kworker/u8:3 Tainted: G E 4.14.0-fscache+ #242
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Workqueue: writeback wb_workfn (flush-afs-2)
task: ffff8800cad72600 task.stack: ffff8800cad44000
RIP: 0010:afs_write_back_from_locked_page+0x19d/0x76c [kafs]
RSP: 0018:ffff8800cad47aa0 EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffff8800bef33a20 RCX: 0000000000000000
RDX: 000000000000000f RSI: ffffffff81c5d0e0 RDI: ffff8800cad72e78
RBP: ffff8800d31ea1e8 R08: ffff8800c1358000 R09: ffff8800ca00e400
R10: ffff8800cad47a38 R11: ffff8800c5d9e400 R12: 0000000000000000
R13: ffffea0002d9df00 R14: ffffffffa0023c1c R15: 0000000000007fdf
FS: 0000000000000000(0000) GS:ffff8800ca700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f85ac6c4000 CR3: 0000000001c10001 CR4: 00000000001606e0
Call Trace:
? clear_page_dirty_for_io+0x23a/0x267
afs_writepages_region+0x1be/0x286 [kafs]
afs_writepages+0x60/0x127 [kafs]
do_writepages+0x36/0x70
__writeback_single_inode+0x12f/0x635
writeback_sb_inodes+0x2cc/0x452
__writeback_inodes_wb+0x68/0x9f
wb_writeback+0x208/0x470
? wb_workfn+0x22b/0x565
wb_workfn+0x22b/0x565
? worker_thread+0x230/0x2ac
process_one_work+0x2cc/0x517
? worker_thread+0x230/0x2ac
worker_thread+0x1d4/0x2ac
? rescuer_thread+0x29b/0x29b
kthread+0x15d/0x165
? kthread_create_on_node+0x3f/0x3f
? call_usermodehelper_exec_async+0x118/0x11f
ret_from_fork+0x24/0x30
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the AFS file locking whereby the use of the big kernel lock (which
could be slept with) was replaced by a spinlock (which couldn't). The
problem is that the AFS code was doing stuff inside the critical section
that might call schedule(), so this is a broken transformation.
Fix this by the following means:
(1) Use a state machine with a proper state that can only be changed under
the spinlock rather than using a collection of bit flags.
(2) Cache the key used for the lock and the lock type in the afs_vnode
struct so that the manager work function doesn't have to refer to a
file_lock struct that's been dequeued. This makes signal handling
safer.
(4) Move the unlock from afs_do_unlk() to afs_fl_release_private() which
means that unlock is achieved in other circumstances too.
(5) Unlock the file on the server before taking the next conflicting lock.
Also change:
(1) Check the permits on a file before actually trying the lock.
(2) fsync the file before effecting an explicit unlock operation. We
don't fsync if the lock is erased otherwise as we might not be in a
context where we can actually do that.
Further fixes:
(1) Fixed-fileserver address rotation is made to work. It's only used by
the locking functions, so couldn't be tested before.
Fixes: 72f98e7255 ("locks: turn lock_flocks into a spinlock")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: jlayton@redhat.com
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Merge tag 'afs-next-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS updates from David Howells:
"kAFS filesystem driver overhaul.
The major points of the overhaul are:
(1) Preliminary groundwork is laid for supporting network-namespacing
of kAFS. The remainder of the namespacing work requires some way
to pass namespace information to submounts triggered by an
automount. This requires something like the mount overhaul that's
in progress.
(2) sockaddr_rxrpc is used in preference to in_addr for holding
addresses internally and add support for talking to the YFS VL
server. With this, kAFS can do everything over IPv6 as well as
IPv4 if it's talking to servers that support it.
(3) Callback handling is overhauled to be generally passive rather
than active. 'Callbacks' are promises by the server to tell us
about data and metadata changes. Callbacks are now checked when
we next touch an inode rather than actively going and looking for
it where possible.
(4) File access permit caching is overhauled to store the caching
information per-inode rather than per-directory, shared over
subordinate files. Whilst older AFS servers only allow ACLs on
directories (shared to the files in that directory), newer AFS
servers break that restriction.
To improve memory usage and to make it easier to do mass-key
removal, permit combinations are cached and shared.
(5) Cell database management is overhauled to allow lighter locks to
be used and to make cell records autonomous state machines that
look after getting their own DNS records and cleaning themselves
up, in particular preventing races in acquiring and relinquishing
the fscache token for the cell.
(6) Volume caching is overhauled. The afs_vlocation record is got rid
of to simplify things and the superblock is now keyed on the cell
and the numeric volume ID only. The volume record is tied to a
superblock and normal superblock management is used to mediate
the lifetime of the volume fscache token.
(7) File server record caching is overhauled to make server records
independent of cells and volumes. A server can be in multiple
cells (in such a case, the administrator must make sure that the
VL services for all cells correctly reflect the volumes shared
between those cells).
Server records are now indexed using the UUID of the server
rather than the address since a server can have multiple
addresses.
(8) File server rotation is overhauled to handle VMOVED, VBUSY (and
similar), VOFFLINE and VNOVOL indications and to handle rotation
both of servers and addresses of those servers. The rotation will
also wait and retry if the server says it is busy.
(9) Data writeback is overhauled. Each inode no longer stores a list
of modified sections tagged with the key that authorised it in
favour of noting the modified region of a page in page->private
and storing a list of keys that made modifications in the inode.
This simplifies things and allows other keys to be used to
actually write to the server if a key that made a modification
becomes useless.
(10) Writable mmap() is implemented. This allows a kernel to be build
entirely on AFS.
Note that Pre AFS-3.4 servers are no longer supported, though this can
be added back if necessary (AFS-3.4 was released in 1998)"
* tag 'afs-next-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (35 commits)
afs: Protect call->state changes against signals
afs: Trace page dirty/clean
afs: Implement shared-writeable mmap
afs: Get rid of the afs_writeback record
afs: Introduce a file-private data record
afs: Use a dynamic port if 7001 is in use
afs: Fix directory read/modify race
afs: Trace the sending of pages
afs: Trace the initiation and completion of client calls
afs: Fix documentation on # vs % prefix in mount source specification
afs: Fix total-length calculation for multiple-page send
afs: Only progress call state at end of Tx phase from rxrpc callback
afs: Make use of the YFS service upgrade to fully support IPv6
afs: Overhaul volume and server record caching and fileserver rotation
afs: Move server rotation code into its own file
afs: Add an address list concept
afs: Overhaul cell database management
afs: Overhaul permit caching
afs: Overhaul the callback handling
afs: Rename struct afs_call server member to cm_server
...
Merge updates from Andrew Morton:
- a few misc bits
- ocfs2 updates
- almost all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
memory hotplug: fix comments when adding section
mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
mm: simplify nodemask printing
mm,oom_reaper: remove pointless kthread_run() error check
mm/page_ext.c: check if page_ext is not prepared
writeback: remove unused function parameter
mm: do not rely on preempt_count in print_vma_addr
mm, sparse: do not swamp log with huge vmemmap allocation failures
mm/hmm: remove redundant variable align_end
mm/list_lru.c: mark expected switch fall-through
mm/shmem.c: mark expected switch fall-through
mm/page_alloc.c: broken deferred calculation
mm: don't warn about allocations which stall for too long
fs: fuse: account fuse_inode slab memory as reclaimable
mm, page_alloc: fix potential false positive in __zone_watermark_ok
mm: mlock: remove lru_add_drain_all()
mm, sysctl: make NUMA stats configurable
shmem: convert shmem_init_inodecache() to void
Unify migrate_pages and move_pages access checks
mm, pagevec: rename pagevec drained field
...
Every pagevec_init user claims the pages being released are hot even in
cases where it is unlikely the pages are hot. As no one cares about the
hotness of pages being released to the allocator, just ditch the
parameter.
No performance impact is expected as the overhead is marginal. The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.
Link: http://lkml.kernel.org/r/20171018075952.10627-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use find_get_pages_range_tag() in afs_writepages_region() as we are
interested only in pages from given range. Remove unnecessary code
after this conversion.
Link: http://lkml.kernel.org/r/20171009151359.31984-16-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Protect call->state changes against the call being prematurely terminated
due to a signal.
What can happen is that a signal causes afs_wait_for_call_to_complete() to
abort an afs_call because it's not yet complete whilst afs_deliver_to_call()
is delivering data to that call.
If the data delivery causes the state to change, this may overwrite the state
of the afs_call, making it not-yet-complete again - but no further
notifications will be forthcoming from AF_RXRPC as the rxrpc call has been
aborted and completed, so kAFS will just hang in various places waiting for
that call or on page bits that need clearing by that call.
A tracepoint to monitor call state changes is also provided.
Signed-off-by: David Howells <dhowells@redhat.com>
Get rid of the afs_writeback record that kAFS is using to match keys with
writes made by that key.
Instead, keep a list of keys that have a file open for writing and/or
sync'ing and iterate through those.
Signed-off-by: David Howells <dhowells@redhat.com>
Introduce a file-private data record for kAFS and put the key into it
rather than storing the key in file->private_data.
Signed-off-by: David Howells <dhowells@redhat.com>
It is not required that the afs client operate on port 7001.
The port could be in use because another kernel or userspace
client has already bound to it.
If the port is in use, just fallback to using a dynamic port.
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Because parsing of the directory wasn't being done under any sort of lock,
the pages holding the directory content can get invalidated whilst the
parsing is ongoing.
Further, the directory page check function gets called outside of the page
lock, so if the page gets cleared or updated, this may return reports of
bad magic numbers in the directory page.
Also, the directory may change size whilst checking and parsing are
ongoing, so more care needs to be taken here.
Fix this by:
(1) Perform the page check from the page filling function before we set
PageUptodate and drop the page lock.
(2) Check for the file having shrunk and the page having been abandoned
before checking the page contents.
(3) Lock the page whilst parsing it for the directory iterator.
Whilst we're at it, add a tracepoint to report check failure.
Signed-off-by: David Howells <dhowells@redhat.com>
Add a pair of tracepoints to log the sending of pages for an FS.StoreData
or FS.StoreData64 operation.
Tracepoint afs_send_pages notes each set of pages added to the operation.
There may be several of these per operation as we get up at most 8
contiguous pages in one go because the bvec we're using is on the stack.
Tracepoint afs_sent_pages notes the end of adding data from a whole run of
pages to the operation and the completion of the request phase.
Signed-off-by: David Howells <dhowells@redhat.com>
Add tracepoints to trace the initiation and completion of client calls
within the kafs filesystem.
The afs_make_vl_call tracepoint watches calls to the volume location
database server.
The afs_make_fs_call tracepoint watches calls to the file server.
The afs_call_done tracepoint watches for call completion.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the total-length calculation in afs_make_call() when the operation
being dispatched has data from a series of pages attached.
Despite the patched code looking like that it should reduce mathematically
to the current code, it doesn't because the 32-bit unsigned arithmetic
being used to calculate the page-offset-difference doesn't correctly extend
to a 64-bit value when the result is effectively negative.
Without this, some FS.StoreData operations that span multiple pages fail,
reporting too little or too much data.
Signed-off-by: David Howells <dhowells@redhat.com>
Only progress the AFS call state at the end of Tx phase from the callback
passed to rxrpc_kernel_send_data() rather than setting it before the last
data send call.
Signed-off-by: David Howells <dhowells@redhat.com>
YFS VL servers offer an upgraded Volume Location service that can return
IPv6 addresses to fileservers and volume servers in addition to IPv4
addresses using the YFSVL.GetEndpoints operation which we should use if
it's available.
To this end:
(1) Make rxrpc_kernel_recv_data() return the call's current service ID so
that the caller can detect service upgrade and see what the service
was upgraded to.
(2) When we see a VL server address we haven't seen before, send a
VL.GetCapabilities operation to it with the service upgrade bit set.
If we get an upgrade to the YFS VL service, change the service ID in
the address list for that address to use the upgraded service and set
a flag to note that this appears to be a YFS-compatible server.
(3) If, when a server's addresses are being looked up, we note that we
previously detected a YFS-compatible server, then send the
YFSVL.GetEndpoints operation rather than VL.GetAddrsU.
(4) Build a fileserver address list from the reply of YFSVL.GetEndpoints,
including both IPv4 and IPv6 addresses. Volume server addresses are
discarded.
(5) The address list is sorted by address and port now, instead of just
address. This allows multiple servers on the same host sitting on
different ports.
Signed-off-by: David Howells <dhowells@redhat.com>
The current code assumes that volumes and servers are per-cell and are
never shared, but this is not enforced, and, indeed, public cells do exist
that are aliases of each other. Further, an organisation can, say, set up
a public cell and a private cell with overlapping, but not identical, sets
of servers. The difference is purely in the database attached to the VL
servers.
The current code will malfunction if it sees a server in two cells as it
assumes global address -> server record mappings and that each server is in
just one cell.
Further, each server may have multiple addresses - and may have addresses
of different families (IPv4 and IPv6, say).
To this end, the following structural changes are made:
(1) Server record management is overhauled:
(a) Server records are made independent of cell. The namespace keeps
track of them, volume records have lists of them and each vnode
has a server on which its callback interest currently resides.
(b) The cell record no longer keeps a list of servers known to be in
that cell.
(c) The server records are now kept in a flat list because there's no
single address to sort on.
(d) Server records are now keyed by their UUID within the namespace.
(e) The addresses for a server are obtained with the VL.GetAddrsU
rather than with VL.GetEntryByName, using the server's UUID as a
parameter.
(f) Cached server records are garbage collected after a period of
non-use and are counted out of existence before purging is allowed
to complete. This protects the work functions against rmmod.
(g) The servers list is now in /proc/fs/afs/servers.
(2) Volume record management is overhauled:
(a) An RCU-replaceable server list is introduced. This tracks both
servers and their coresponding callback interests.
(b) The superblock is now keyed on cell record and numeric volume ID.
(c) The volume record is now tied to the superblock which mounts it,
and is activated when mounted and deactivated when unmounted.
This makes it easier to handle the cache cookie without causing a
double-use in fscache.
(d) The volume record is loaded from the VLDB using VL.GetEntryByNameU
to get the server UUID list.
(e) The volume name is updated if it is seen to have changed when the
volume is updated (the update is keyed on the volume ID).
(3) The vlocation record is got rid of and VLDB records are no longer
cached. Sufficient information is stored in the volume record, though
an update to a volume record is now no longer shared between related
volumes (volumes come in bundles of three: R/W, R/O and backup).
and the following procedural changes are made:
(1) The fileserver cursor introduced previously is now fleshed out and
used to iterate over fileservers and their addresses.
(2) Volume status is checked during iteration, and the server list is
replaced if a change is detected.
(3) Server status is checked during iteration, and the address list is
replaced if a change is detected.
(4) The abort code is saved into the address list cursor and -ECONNABORTED
returned in afs_make_call() if a remote abort happened rather than
translating the abort into an error message. This allows actions to
be taken depending on the abort code more easily.
(a) If a VMOVED abort is seen then this is handled by rechecking the
volume and restarting the iteration.
(b) If a VBUSY, VRESTARTING or VSALVAGING abort is seen then this is
handled by sleeping for a short period and retrying and/or trying
other servers that might serve that volume. A message is also
displayed once until the condition has cleared.
(c) If a VOFFLINE abort is seen, then this is handled as VBUSY for the
moment.
(d) If a VNOVOL abort is seen, the volume is rechecked in the VLDB to
see if it has been deleted; if not, the fileserver is probably
indicating that the volume couldn't be attached and needs
salvaging.
(e) If statfs() sees one of these aborts, it does not sleep, but
rather returns an error, so as not to block the umount program.
(5) The fileserver iteration functions in vnode.c are now merged into
their callers and more heavily macroised around the cursor. vnode.c
is removed.
(6) Operations on a particular vnode are serialised on that vnode because
the server will lock that vnode whilst it operates on it, so a second
op sent will just have to wait.
(7) Fileservers are probed with FS.GetCapabilities before being used.
This is where service upgrade will be done.
(8) A callback interest on a fileserver is set up before an FS operation
is performed and passed through to afs_make_call() so that it can be
set on the vnode if the operation returns a callback. The callback
interest is passed through to afs_iget() also so that it can be set
there too.
In general, record updating is done on an as-needed basis when we try to
access servers, volumes or vnodes rather than offloading it to work items
and special threads.
Notes:
(1) Pre AFS-3.4 servers are no longer supported, though this can be added
back if necessary (AFS-3.4 was released in 1998).
(2) VBUSY is retried forever for the moment at intervals of 1s.
(3) /proc/fs/afs/<cell>/servers no longer exists.
Signed-off-by: David Howells <dhowells@redhat.com>
Add an RCU replaceable address list structure to hold a list of server
addresses. The list also holds the
To this end:
(1) A cell's VL server address list can be loaded directly via insmod or
echo to /proc/fs/afs/cells or dynamically from a DNS query for AFSDB
or SRV records.
(2) Anyone wanting to use a cell's VL server address must wait until the
cell record comes online and has tried to obtain some addresses.
(3) An FS server's address list, for the moment, has a single entry that
is the key to the server list. This will change in the future when a
server is instead keyed on its UUID and the VL.GetAddrsU operation is
used.
(4) An 'address cursor' concept is introduced to handle iteration through
the address list. This is passed to the afs_make_call() as, in the
future, stuff (such as abort code) that doesn't outlast the call will
be returned in it.
In the future, we might want to annotate the list with information about
how each address fares. We might then want to propagate such annotations
over address list replacement.
Whilst we're at it, we allow IPv6 addresses to be specified in
colon-delimited lists by enclosing them in square brackets.
Signed-off-by: David Howells <dhowells@redhat.com>
Overhaul the way that the in-kernel AFS client keeps track of cells in the
following manner:
(1) Cells are now held in an rbtree to make walking them quicker and RCU
managed (though this is probably overkill).
(2) Cells now have a manager work item that:
(A) Looks after fetching and refreshing the VL server list.
(B) Manages cell record lifetime, including initialising and
destruction.
(B) Manages cell record caching whereby threads are kept around for a
certain time after last use and then destroyed.
(C) Manages the FS-Cache index cookie for a cell. It is not permitted
for a cookie to be in use twice, so we have to be careful to not
allow a new cell record to exist at the same time as an old record
of the same name.
(3) Each AFS network namespace is given a manager work item that manages
the cells within it, maintaining a single timer to prod cells into
updating their DNS records.
This uses the reduce_timer() facility to make the timer expire at the
soonest timed event that needs happening.
(4) When a module is being unloaded, cells and cell managers are now
counted out using dec_after_work() to make sure the module text is
pinned until after the data structures have been cleaned up.
(5) Each cell's VL server list is now protected by a seqlock rather than a
semaphore.
Signed-off-by: David Howells <dhowells@redhat.com>
Overhaul permit caching in AFS by making it per-vnode and sharing permit
lists where possible.
When most of the fileserver operations are called, they return a status
structure indicating the (revised) details of the vnode or vnodes involved
in the operation. This includes the access mark derived from the ACL
(named CallerAccess in the protocol definition file). This is cacheable
and if the ACL changes, the server will tell us that it is breaking the
callback promise, at which point we can discard the currently cached
permits.
With this patch, the afs_permits structure has, at the end, an array of
{ key, CallerAccess } elements, sorted by key pointer. This is then cached
in a hash table so that it can be shared between vnodes with the same
access permits.
Permit lists can only be shared if they contain the exact same set of
key->CallerAccess mappings.
Note that that table is global rather than being per-net_ns. If the keys
in a permit list cross net_ns boundaries, there is no problem sharing the
cached permits, since the permits are just integer masks.
Since permit lists pin keys, the permit cache also makes it easier for a
future patch to find all occurrences of a key and remove them by means of
setting the afs_permits::invalidated flag and then clearing the appropriate
key pointer. In such an event, memory barriers will need adding.
Lastly, the permit caching is skipped if the server has sent either a
vnode-specific or an entire-server callback since the start of the
operation.
Signed-off-by: David Howells <dhowells@redhat.com>
Overhaul the AFS callback handling by the following means:
(1) Don't give up callback promises on vnodes that we are no longer using,
rather let them just expire on the server or let the server break
them. This is actually more efficient for the server as the callback
lookup is expensive if there are lots of extant callbacks.
(2) Only give up the callback promises we have from a server when the
server record is destroyed. Then we can just give up *all* the
callback promises on it in one go.
(3) Servers can end up being shared between cells if cells are aliased, so
don't add all the vnodes being backed by a particular server into a
big FID-indexed tree on that server as there may be duplicates.
Instead have each volume instance (~= superblock) register an interest
in a server as it starts to make use of it and use this to allow the
processor for callbacks from the server to find the superblock and
thence the inode corresponding to the FID being broken by means of
ilookup_nowait().
(4) Rather than iterating over the entire callback list when a mass-break
comes in from the server, maintain a counter of mass-breaks in
afs_server (cb_seq) and make afs_validate() check it against the copy
in afs_vnode.
It would be nice not to have to take a read_lock whilst doing this,
but that's tricky without using RCU.
(5) Save a ref on the fileserver we're using for a call in the afs_call
struct so that we can access its cb_s_break during call decoding.
(6) Write-lock around callback and status storage in a vnode and read-lock
around getattr so that we don't see the status mid-update.
This has the following consequences:
(1) Data invalidation isn't seen until someone calls afs_validate() on a
vnode. Unfortunately, we need to use a key to query the server, but
getting one from a background thread is tricky without caching loads
of keys all over the place.
(2) Mass invalidation isn't seen until someone calls afs_validate().
(3) Callback breaking is going to hit the inode_hash_lock quite a bit.
Could this be replaced with rcu_read_lock() since inodes are destroyed
under RCU conditions.
Signed-off-by: David Howells <dhowells@redhat.com>
Rename the server member of struct afs_call to cm_server as we're only
going to be using it for incoming calls for the Cache Manager service.
This makes it easier to differentiate from the pointer to the target server
for the client, which will point to a different structure to allow for
callback handling.
Signed-off-by: David Howells <dhowells@redhat.com>
In AFS's encoding of a UUID, the eight 'char' fields are all signed, so
represent them with __s8 rather than __u8. This makes the compiler
sign-extend them correctly when XDR-encoding them.
Signed-off-by: David Howells <dhowells@redhat.com>
The handler for the CB.ProbeUuid operation in the cache manager is
implemented, but isn't listed in the switch-statement of operation
selection, so won't be used. Fix this by adding it.
Signed-off-by: David Howells <dhowells@redhat.com>
If call->ret_reply0 is set, return call->reply[0] on success. Change the
return type of afs_make_call() to long so that this can be passed back
without bit loss and then cast to a pointer if required.
Signed-off-by: David Howells <dhowells@redhat.com>
The AFS abort code space is shared across all services, so there's no need
for separate abort_to_error translators for each service.
Consolidate them into a single function and remove the function pointers
for them.
Signed-off-by: David Howells <dhowells@redhat.com>
Allow VL server specifications to be given IPv6 addresses as well as IPv4
addresses, for example as:
echo add foo.org 1111:2222:3333:0:4444:5555:6666:7777 >/proc/fs/afs/cells
Note that ':' is the expected separator for separating IPv4 addresses, but
if a ',' is detected or no '.' is detected in the string, the delimiter is
switched to ','.
This also works with DNS AFSDB or SRV record strings fetched by upcall from
userspace.
Signed-off-by: David Howells <dhowells@redhat.com>
Keep and pass sockaddr_rxrpc addresses around rather than keeping and
passing in_addr addresses to allow for the use of IPv6 and non-standard
port numbers in future.
This also allows the port and service_id fields to be removed from the
afs_call struct.
Signed-off-by: David Howells <dhowells@redhat.com>
Update the cache index structure in the following ways:
(1) Don't use the volume name followed by the volume type as levels in the
cache index. Volumes can be renamed. Use the volume ID instead.
(2) Don't store the VLDB data for a volume in the tree. If the volume
database should be cached locally, then it should be done in a separate
tree.
(3) Expand the volume ID stored in the cache to 64 bits.
(4) Expand the file/vnode ID stored in the cache to 96 bits.
(5) Increment the cache structure version number to 1.
Signed-off-by: David Howells <dhowells@redhat.com>
Add some protocol definitions, including max field lengths, flag defs, an
XDR-encoded UUID def, more VL operation IDs and more fileserver abort
codes.
Signed-off-by: David Howells <dhowells@redhat.com>
Push the network namespace pointer to more places in AFS, including the
afs_server structure (which doesn't hold a ref on the netns).
In particular, afs_put_cell() now takes requires a net ns parameter so that
it can safely alter the netns after decrementing the cell usage count - the
cell will be deallocated by a background thread after being cached for a
period, which means that it's not safe to access it after reducing its
usage count.
Signed-off-by: David Howells <dhowells@redhat.com>
Keep a reference to the cell in the superblock info structure in addition
to the volume and net pointers. This will make it easier to clean up in a
future patch in which afs_put_volume() will need the cell pointer.
Whilst we're at it, make the cell and volume getting functions return a
pointer to the object got to make the call sites look neater.
Signed-off-by: David Howells <dhowells@redhat.com>
Fix server reaping and make sure it's all done before we start trying to
purge cells, given that servers currently pin cells.
Signed-off-by: David Howells <dhowells@redhat.com>
Close the rxrpc socket only after we've purged the server records (and also
cell and volume records which might refer to servers) so that we can give
up the callbacks on each server.
Signed-off-by: David Howells <dhowells@redhat.com>
Lay the groundwork for supporting network namespaces (netns) to the AFS
filesystem by moving various global features to a network-namespace struct
(afs_net) and providing an instance of this as a temporary global variable
that everything uses via accessor functions for the moment.
The following changes have been made:
(1) Store the netns in the superblock info. This will be obtained from
the mounter's nsproxy on a manual mount and inherited from the parent
superblock on an automount.
(2) The cell list is made per-netns. It can be viewed through
/proc/net/afs/cells and also be modified by writing commands to that
file.
(3) The local workstation cell is set per-ns in /proc/net/afs/rootcell.
This is unset by default.
(4) The 'rootcell' module parameter, which sets a cell and VL server list
modifies the init net namespace, thereby allowing an AFS root fs to be
theoretically used.
(5) The volume location lists and the file lock manager are made
per-netns.
(6) The AF_RXRPC socket and associated I/O bits are made per-ns.
The various workqueues remain global for the moment.
Changes still to be made:
(1) /proc/fs/afs/ should be moved to /proc/net/afs/ and a symlink emplaced
from the old name.
(2) A per-netns subsys needs to be registered for AFS into which it can
store its per-netns data.
(3) Rather than the AF_RXRPC socket being opened on module init, it needs
to be opened on the creation of a superblock in that netns.
(4) The socket needs to be closed when the last superblock using it is
destroyed and all outstanding client calls on it have been completed.
This prevents a reference loop on the namespace.
(5) It is possible that several namespaces will want to use AFS, in which
case each one will need its own UDP port. These can either be set
through /proc/net/afs/cm_port or the kernel can pick one at random.
The init_ns gets 7001 by default.
Other issues that need resolving:
(1) The DNS keyring needs net-namespacing.
(2) Where do upcalls go (eg. DNS request-key upcall)?
(3) Need something like open_socket_in_file_ns() syscall so that AFS
command line tools attempting to operate on an AFS file/volume have
their RPC calls go to the right place.
Signed-off-by: David Howells <dhowells@redhat.com>
Make wait_on_atomic_t() pass the TASK_* mode onto its action function as an
extra argument and make it 'unsigned int throughout.
Also, consolidate a bunch of identical action functions into a default
function that can do the appropriate thing for the mode.
Also, change the argument name in the bit_wait*() function declarations to
reflect the fact that it's the mode and not the bit number.
[Peter Z gives this a grudging ACK, but thinks that the whole atomic_t wait
should be done differently, though he's not immediately sure as to how]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
cc: Ingo Molnar <mingo@kernel.org>
Files removed in 'net-next' had their license header updated
in 'net'. We take the remove from 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
