Commit Graph

552 Commits

Author SHA1 Message Date
Marc Dionne f7f1dd3162 afs: Check for rxrpc call completion in wait loop
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>
2019-04-12 16:57:23 -07:00
Marc Dionne 4611da30d6 rxrpc: Make rxrpc_kernel_check_life() indicate if call completed
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>
2019-04-12 16:57:23 -07:00
David Howells 8c7ae38d1c afs: Fix StoreData op marshalling
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>
2019-03-28 08:54:20 -07:00
Linus Torvalds 7b47a9e7c8 Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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
  ...
2019-03-12 14:08:19 -07:00
Nikolay Borisov b5420237ec mm: refactor readahead defines in mm.h
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>
2019-03-12 10:04:01 -07:00
David Howells c99c2171fc afs: Use fs_context to pass parameters over automount
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>
2019-02-28 03:29:39 -05:00
David Howells 13fcc68370 afs: Add fs_context support
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>
2019-02-28 03:29:38 -05:00
David Howells 7d762d6914 afs: Fix manually set volume location server list
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>
2019-02-25 11:59:07 -08:00
David Howells 34fa47612b afs: Fix race in async call refcounting
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>
2019-01-17 15:17:28 +00:00
David Howells 7a75b0079a afs: Provide a function to get a ref on a call
Provide a function to get a reference on an afs_call struct.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17 15:17:28 +00:00
David Howells 59d49076ae afs: Fix key refcounting in file locking code
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>
2019-01-17 15:17:28 +00:00
Marc Dionne 4882a27cec afs: Don't set vnode->cb_s_break in afs_validate()
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>
2019-01-17 15:15:52 +00:00
Marc Dionne 5edc22cc1d afs: Set correct lock type for the yfs CreateFile
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>
2019-01-10 17:12:05 +00:00
Gustavo A. R. Silva c2b8bd49d3 afs: Use struct_size() in kzalloc()
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>
2019-01-10 17:12:05 +00:00
Nikolay Borisov f86196ea87 fs: don't open code lru_to_page()
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>
2019-01-04 13:13:48 -08:00
Davidlohr Bueso 08d405c8b8 fs/: remove caller signal_pending branch predictions
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>
2019-01-04 13:13:48 -08:00
Linus Torvalds 5f1ca5c619 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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
2018-11-30 10:47:50 -08:00
David Howells 73116df7bb afs: Use d_instantiate() rather than d_add() and don't d_drop()
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>
2018-11-29 21:08:14 -05:00
David Howells 4584ae96ae afs: Fix missing net error handling
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>
2018-11-29 21:08:14 -05:00
David Howells ae3b7361dc afs: Fix validation/callback interaction
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>
2018-11-29 21:08:14 -05:00
David Howells 7150ceaacb rxrpc: Fix life check
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>
2018-11-15 11:35:40 -08:00
David Howells 3bf0fb6f33 afs: Probe multiple fileservers simultaneously
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>
2018-10-24 00:41:09 +01:00
David Howells 18ac61853c afs: Fix callback handling
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>
2018-10-24 00:41:09 +01:00
David Howells 2feeaf8433 afs: Eliminate the address pointer from the address list cursor
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>
2018-10-24 00:41:09 +01:00
David Howells 744bcd713a afs: Allow dumping of server cursor on operation failure
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>
2018-10-24 00:41:09 +01:00
David Howells 30062bd13e afs: Implement YFS support in the fs client
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>
2018-10-24 00:41:08 +01:00
David Howells d4936803a9 afs: Expand data structure fields to support YFS
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>
2018-10-24 00:41:08 +01:00
David Howells f58db83fd3 afs: Get the target vnode in afs_rmdir() and get a callback on it
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>
2018-10-24 00:41:08 +01:00
David Howells 12d8e95a91 afs: Calc callback expiry in op reply delivery
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>
2018-10-24 00:41:08 +01:00
David Howells 36bb5f490a afs: Fix FS.FetchStatus delivery from updating wrong vnode
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>
2018-10-24 00:41:08 +01:00
David Howells 35dbfba311 afs: Implement the YFS cache manager service
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>
2018-10-24 00:41:08 +01:00
David Howells 06aeb29714 afs: Remove callback details from afs_callback_break struct
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>
2018-10-24 00:41:08 +01:00
David Howells 0067191201 afs: Commit the status on a new file/dir/symlink
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>
2018-10-24 00:41:08 +01:00
David Howells 3b6492df41 afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
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>
2018-10-24 00:41:08 +01:00
David Howells 2a0b4f64c9 afs: Don't invoke the server to read data beyond EOF
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>
2018-10-24 00:41:08 +01:00
David Howells f51375cd9e afs: Add a couple of tracepoints to log I/O errors
Add a couple of tracepoints to log the production of I/O errors within the AFS
filesystem.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
David Howells 4ac15ea536 afs: Handle EIO from delivery function
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>
2018-10-24 00:41:07 +01:00
David Howells ded2f4c58a afs: Fix TTL on VL server and address lists
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>
2018-10-24 00:41:07 +01:00
David Howells 0a5143f2f8 afs: Implement VL server rotation
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>
2018-10-24 00:41:07 +01:00
David Howells e7f680f45b afs: Improve FS server rotation error handling
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>
2018-10-24 00:41:07 +01:00
David Howells 12bdcf333f afs: Set up the iov_iter before calling afs_extract_data()
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>
2018-10-24 00:41:07 +01:00
David Howells 160cb9574b afs: Better tracing of protocol errors
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>
2018-10-24 00:41:07 +01:00
David Howells aa563d7bca iov_iter: Separate type from direction and use accessor functions
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>
2018-10-24 00:41:07 +01:00
David S. Miller 2e2d6f0342 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
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>
2018-10-19 11:03:06 -07:00
David Howells f0a7d1883d afs: Fix clearance of reply
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>
2018-10-15 15:31:47 +02:00
David S. Miller d864991b22 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
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>
2018-10-12 21:38:46 -07:00
David Howells f014ffb025 afs: Fix afs_server struct leak
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>
2018-10-12 17:36:40 +02:00
David Howells 6b3944e42e afs: Fix cell proc list
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>
2018-10-12 13:18:57 +02:00
David Howells 46894a1359 rxrpc: Use IPv4 addresses throught the IPv6
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>
2018-10-04 09:32:28 +01:00
David Howells 66be646bd9 afs: Sort address lists so that they are in logical ascending order
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>
2018-10-04 09:32:28 +01:00