afs: trace: Log afs_make_call(), including server address

Add a tracepoint to log calls to afs_make_call(), including the destination
server address.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org

afs: Parse the VolSync record in the reply of a number of RPC ops

A number of fileserver RPC operations return a VolSync record as part of
their reply that gives some information about the state of the volume being
accessed, including:

(1) A volume Creation timestamp. For an RW volume, this is the time at
which the volume was created; if it changes, the RW volume was
presumably restored from a backup and all cached data should be
scrubbed as Data Version numbers could regress on the files in the
volume.

For an RO volume, this is the time it was last snapshotted from the RW
volume. It is expected to advance each time this happens; if it
regresses, cached data should be scrubbed.

(2) A volume Update timestamp (Auristor only). For an RW volume, this is
updated any time any change is made to a volume or its contents. If
it regresses, all cached data must be scrubbed.

For an RO volume, this is a copy of the RW volume's Update timestamp
at the point of snapshotting. It can be used as a version number when
checking to see if a callback on a RO volume was due to a snapshot.
If it regresses, all cached data must be scrubbed.

but this is currently not made use of by the in-kernel afs filesystem.

Make the afs filesystem use this by:

(1) Add an update time field to the afs_volsync struct and use a value of
TIME64_MIN in both that and the creation time to indicate that they
are unset.

(2) Add creation and update time fields to the afs_volume struct and use
this to track the two timestamps.

(3) Add a volsync_lock mutex to the afs_volume struct to control
modification access for when we detect a change in these values.

(3) Add a 'pre-op volsync' struct to the afs_operation struct to record
the state of the volume tracking before the op.

(4) Add a new counter, cb_scrub, to the afs_volume struct to count events
that require all data to be scrubbed. A copy is placed in the
afs_vnode struct (inode) and if they no longer match, a scrub takes
place.

(5) When the result of an operation is being parsed, parse the VolSync
data too, if it is provided. Note that the two timestamps are handled
separately, since they don't work in quite the same way.

- If the afs_volume tracking is unset, just set it and do nothing
else.

- If the result timestamps are the same as the ones in afs_volume, do
nothing.

- If the timestamps regress, increment cb_scrub if not already done
so.

- If the creation timestamp on a RW volume changes, increment cb_scrub
if not already done so.

- If the creation timestamp on a RO volume advances, update the server
list and see if the current server has been excluded, if so reissue
the op. Once over half of the replication sites have been updated,
increment cb_ro_snapshot to indicate updates may be required and
switch over to excluding unupdated replication sites.

- If the creation timestamp on a Backup volume advances, just
increment cb_ro_snapshot to trigger updates.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org

afs: Use the operation issue time instead of the reply time for callbacks

rxrpc and kafs between them try to use the receive timestamp on the first
data packet (ie. the one with sequence number 1) as a base from which to
calculate the time at which callback promise and lock expiration occurs.

However, we don't know how long it took for the server to send us the reply
from it having completed the basic part of the operation - it might then,
for instance, have to send a bunch of a callback breaks, depending on the
particular operation.

Fix this by using the time at which the operation is issued on the client
as a base instead. That should never be longer than the server's idea of
the expiry time.

Fixes: 781070551c26 ("afs: Fix calculation of callback expiry time")
Fixes: 2070a3e44962 ("rxrpc: Allow the reply time to be obtained on a client call")
Suggested-by: Jeffrey E Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Set mtime from the client for yfs create operations

For operations that create vnodes on the server such as CreateFile,
MakeDir or Symlink, the server will store its own current time as
the mtime if the client doesn't pass in a time in the accompanying
StoreStatus structure.

If the server and client clocks are not well synchronized, the client
may see timestamps in the future or inconsistent dependency checks
with "make" for files that are not modified after creation:

make[2]: Warning: File 'arch/x86/kernel/apic/modules.order' has
modification time 0.14 s in the future
make[2]: warning: Clock skew detected. Your build may be incomplete.

This is already handled correctly for non yfs operations; also
set the mtime for the corresponding yfs operations.

Changes:
v3: Replace S_IRWXUGO with 0777, per checkpatch
v2: [dhowells] Merge the two xdr_encode_YFSStoreStatus*() functions together

Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: http://lists.infradead.org/pipermail/linux-afs/2021-October/004395.html

afs: Use the fs operation ops to handle FetchData completion

Use the 'success' and 'aborted' afs_operations_ops methods and add a
'failed' method to handle the completion of an AFS.FetchData,
AFS.FetchData64 or YFS.FetchData64 RPC operation rather than directly
calling the done func pointed to by the afs_read struct from the call
delivery handler.

This means the done function will be called back on error also, not just on
successful completion.

This allows motion towards asynchronous data reception on data fetch calls
and allows any error to be handed off to the fscache read helper in the
same place as a successful completion.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588541471.3465195.8807019223378490810.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118157260.1232039.6549085372718234792.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161052647.2537118.12922380836599003659.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340417106.1303470.3502017303898569631.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539560673.286939.391310781674212229.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653816367.2770958.5856904574822446404.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789099994.6155.473719823490561190.stgit@warthog.procyon.org.uk/ # v6

afs: Use ITER_XARRAY for writing

Use a single ITER_XARRAY iterator to describe the portion of a file to be
transmitted to the server rather than generating a series of small
ITER_BVEC iterators on the fly. This will make it easier to implement AIO
in afs.

In theory we could maybe use one giant ITER_BVEC, but that means
potentially allocating a huge array of bio_vec structs (max 256 per page)
when in fact the pagecache already has a structure listing all the relevant
pages (radix_tree/xarray) that can be walked over.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/153685395197.14766.16289516750731233933.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/158861251312.340223.17924900795425422532.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465828607.1377938.6903132788463419368.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588535018.3465195.14509994354240338307.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118152415.1232039.6452879415814850025.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161048194.2537118.13763612220937637316.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340411602.1303470.4661108879482218408.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539555629.286939.5241869986617154517.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653811456.2770958.7017388543246759245.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789095005.6155.6789055030327407928.stgit@warthog.procyon.org.uk/ # v6

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_XARRAY iterator when reading data to load directly
into the inode's pages without needing to create a list of them.

This will allow O_DIRECT calls to be supported in future patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/152898380012.11616.12094591785228251717.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/153685394431.14766.3178466345696987059.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/153999787395.866.11218209749223643998.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/154033911195.12041.3882700371848894587.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/158861250059.340223.1248231474865140653.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465827399.1377938.11181327349704960046.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588533776.3465195.3612752083351956948.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118151238.1232039.17015723405750601161.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161047240.2537118.14721975104810564022.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340410333.1303470.16260122230371140878.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539554187.286939.15305559004905459852.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653810525.2770958.4630666029125411789.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789093719.6155.7877160739235087723.stgit@warthog.procyon.org.uk/ # v6

afs: Don't truncate iter during data fetch

Don't truncate the iterator to correspond to the actual data size when
fetching the data from the server - rather, pass the length we want to read
to rxrpc.

This will allow the clear-after-read code in future to simply clear the
remaining iterator capacity rather than having to reinitialise the
iterator.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/158861249201.340223.13035445866976590375.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465825061.1377938.14403904452300909320.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588531418.3465195.10712005940763063144.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118148567.1232039.13380313332292947956.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161044610.2537118.17908520793806837792.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340407907.1303470.6501394859511712746.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539551721.286939.14655713136572200716.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653807790.2770958.14034599989374173734.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789090823.6155.15673999934535049102.stgit@warthog.procyon.org.uk/ # v6

afs: Fix warning due to unadvanced marshalling pointer

When using the afs.yfs.acl xattr to change an AuriStor ACL, a warning
can be generated when the request is marshalled because the buffer
pointer isn't increased after adding the last element, thereby
triggering the check at the end if the ACL wasn't empty. This just
causes something like the following warning, but doesn't stop the call
from happening successfully:

kAFS: YFS.StoreOpaqueACL2: Request buffer underflow (36<108)

Fix this simply by increasing the count prior to the check.

Fixes: f5e4546347bc ("afs: Implement YFS ACL setting")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

afs: Fix yfs_fs_fetch_status() to honour vnode selector

Fix yfs_fs_fetch_status() to honour the vnode selector in
op->fetch_status.which as does afs_fs_fetch_status() that allows
afs_do_lookup() to use this as an alternative to the InlineBulkStatus RPC
call if not implemented by the server.

This doesn't matter in the current code as YFS servers always implement
InlineBulkStatus, but a subsequent will call it on YFS servers too in some
circumstances.

Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Remove yfs_fs_fetch_file_status() as it's not used

Remove yfs_fs_fetch_file_status() as it's no longer used.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Remove afs_zero_fid as it's not used

Remove afs_zero_fid as it's not used.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Reorganise volume and server trees to be rooted on the cell

Reorganise afs_volume objects such that they're in a tree keyed on volume
ID, rooted at on an afs_cell object rather than being in multiple trees,
each of which is rooted on an afs_server object.

afs_server structs become per-cell and acquire a pointer to the cell.

The process of breaking a callback then starts with finding the server by
its network address, following that to the cell and then looking up each
volume ID in the volume tree.

This is simpler than the afs_vol_interest/afs_cb_interest N:M mapping web
and allows those structs and the code for maintaining them to be simplified
or removed.

It does make a couple of things a bit more tricky, though:

(1) Operations now start with a volume, not a server, so there can be more
than one answer as to whether or not the server we'll end up using
supports the FS.InlineBulkStatus RPC.

(2) CB RPC operations that specify the server UUID. There's still a tree
of servers by UUID on the afs_net struct, but the UUIDs in it aren't
guaranteed unique.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Build an abstraction around an "operation" concept

Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:

(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.

(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.

(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:

- The vnode pointer.

- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).

- The status and callback information that may be returned in the
reply about the vnode.

- Callback break and data version tracking for detecting
simultaneous third-parth changes.

(4) Pointers to dentries to be updated with new inodes.

(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.

To make this work, the following function restructuring is made:

(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.

(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.

(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.

(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.

(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.

(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.

(G) The inode status init/update functions now also take an op and a vnode
record.

(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.

(I) The call is attached to the operation and then the operation core does
the waiting.

And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.

This lays the foundation for the following changes in the future:

(*) Overhauling the rotation (again).

(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Rename struct afs_fs_cursor to afs_operation

As a prelude to implementing asynchronous fileserver operations in the afs
filesystem, rename struct afs_fs_cursor to afs_operation.

This struct is going to form the core of the operation management and is
going to acquire more members in later.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Remove the error argument from afs_protocol_error()

Remove the error argument from afs_protocol_error() as it's always
-EBADMSG.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Set error flag rather than return error from file status decode

Set a flag in the call struct to indicate an unmarshalling error rather
than return and handle an error from the decoding of file statuses. This
flag is checked on a successful return from the delivery function.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Don't unlock fetched data pages until the op completes successfully

Don't call req->page_done() on each page as we finish filling it with
the data coming from the network. Whilst this might speed up the
application a bit, it's a problem if there's a network failure and the
operation has to be reissued.

If this happens, an oops occurs because afs_readpages_page_done() clears
the pointer to each page it unlocks and when a retry happens, the
pointers to the pages it wants to fill are now NULL (and the pages have
been unlocked anyway).

Instead, wait till the operation completes successfully and only then
release all the pages after clearing any terminal gap (the server can
give us less data than we requested as we're allowed to ask for more
than is available).

KASAN produces a bug like the following, and even without KASAN, it can
oops and panic.

BUG: KASAN: wild-memory-access in _copy_to_iter+0x323/0x5f4
Write of size 1404 at addr 0005088000000000 by task md5sum/5235

CPU: 0 PID: 5235 Comm: md5sum Not tainted 5.7.0-rc3-fscache+ #250
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Call Trace:
memcpy+0x39/0x58
_copy_to_iter+0x323/0x5f4
__skb_datagram_iter+0x89/0x2a6
skb_copy_datagram_iter+0x129/0x135
rxrpc_recvmsg_data.isra.0+0x615/0xd42
rxrpc_kernel_recv_data+0x1e9/0x3ae
afs_extract_data+0x139/0x33a
yfs_deliver_fs_fetch_data64+0x47a/0x91b
afs_deliver_to_call+0x304/0x709
afs_wait_for_call_to_complete+0x1cc/0x4ad
yfs_fs_fetch_data+0x279/0x288
afs_fetch_data+0x1e1/0x38d
afs_readpages+0x593/0x72e
read_pages+0xf5/0x21e
__do_page_cache_readahead+0x128/0x23f
ondemand_readahead+0x36e/0x37f
generic_file_buffered_read+0x234/0x680
new_sync_read+0x109/0x17e
vfs_read+0xe6/0x138
ksys_read+0xd8/0x14d
do_syscall_64+0x6e/0x8a
entry_SYSCALL_64_after_hwframe+0x49/0xb3

Fixes: 196ee9cd2d04 ("afs: Make afs_fs_fetch_data() take a list of pages")
Fixes: 30062bd13e36 ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

afs: Fix length of dump of bad YFSFetchStatus record

Fix the length of the dump of a bad YFSFetchStatus record. The function
was copied from the AFS version, but the YFS variant contains bigger fields
and extra information, so expand the dump to match.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix rename operation status delivery

The afs_deliver_fs_rename() and yfs_deliver_fs_rename() functions both only
decode the second file status returned unless the parent directories are
different - unfortunately, this means that the xdr pointer isn't advanced
and the volsync record will be read incorrectly in such an instance.

Fix this by always decoding the second status into the second
status/callback block which wasn't being used if the dirs were the same.

The afs_update_dentry_version() calls that update the directory data
version numbers on the dentries can then unconditionally use the second
status record as this will always reflect the state of the destination dir
(the two records will be identical if the destination dir is the same as
the source dir)

Fixes: 260a980317da ("[AFS]: Add "directory write" support.")
Fixes: 30062bd13e36 ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix missing XDR advance in xdr_decode_{AFS,YFS}FSFetchStatus()

If we receive a status record that has VNOVNODE set in the abort field,
xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() don't advance
the XDR pointer, thereby corrupting anything subsequent decodes from the
same block of data.

This has the potential to affect AFS.InlineBulkStatus and
YFS.InlineBulkStatus operation, but probably doesn't since the status
records are extracted as individual blocks of data and the buffer pointer
is reset between blocks.

It does affect YFS.RemoveFile2 operation, corrupting the volsync record -
though that is not currently used.

Other operations abort the entire operation rather than returning an error
inline, in which case there is no decoding to be done.

Fix this by unconditionally advancing the xdr pointer.

Fixes: 684b0f68cf1c ("afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Introduce an afs_get_read() refcount helper

Introduce an afs_get_read() helper to get a reference on an afs_read
object.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Switch the naming of call->iter and call->_iter

Change the name of call->iter to call->def_iter to represent the default
iterator.

Change the name of call->_iter to call->iter to represent the iterator
actually being used.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Use call->_iter not &call->iter in debugging statements

Use call->_iter not &call->iter in debugging statements as the latter is a
convenience iter whereas the former represents we're actually doing at the
moment.

Signed-off-by: David Howells <dhowells@redhat.com>

fs: afs: Use pr_warn instead of pr_warning

As said in commit f2c2cbcc35d4 ("powerpc: Use pr_warn instead of
pr_warning"), removing pr_warning so all logging messages use a
consistent <prefix>_warn style. Let's do it.

Link: http://lkml.kernel.org/r/20191018031850.48498-23-wangkefeng.wang@huawei.com
To: linux-kernel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>

afs: Use afs_extract_discard() rather than iov_iter_discard()

Use afs_extract_discard() rather than iov_iter_discard() as the former is a
wrapper for the latter, providing a place to put tracepoints.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: use correct afs_call_type in yfs_fs_store_opaque_acl2

It seems that 'yfs_RXYFSStoreOpaqueACL2' should be use in
yfs_fs_store_opaque_acl2().

Fixes: f5e4546347bc ("afs: Implement YFS ACL setting")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>

afs: yfsclient: Mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

fs/afs/yfsclient.c: In function ‘yfs_deliver_fs_fetch_opaque_acl’:
fs/afs/yfsclient.c:1984:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
call->unmarshall++;
~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:1987:2: note: here
case 1:
^~~~
fs/afs/yfsclient.c:2005:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
call->unmarshall++;
~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2008:2: note: here
case 2:
^~~~
fs/afs/yfsclient.c:2014:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
call->unmarshall++;
~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2017:2: note: here
case 3:
^~~~
fs/afs/yfsclient.c:2035:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
call->unmarshall++;
~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2038:2: note: here
case 4:
^~~~
fs/afs/yfsclient.c:2047:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
call->unmarshall++;
~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2050:2: note: here
case 5:
^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

Also, fix some commenting style issues.

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public licence as published by
the free software foundation either version 2 of the licence or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 114 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

afs: Fix unlink to handle YFS.RemoveFile2 better

Make use of the status update for the target file that the YFS.RemoveFile2
RPC op returns to correctly update the vnode as to whether the file was
actually deleted or just had nlink reduced.

Fixes: 30062bd13e36 ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Don't save callback version and type fields

Don't save callback version and type fields as the version is about the
format of the callback information and the type is relative to the
particular RPC call.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix application of status and callback to be under same lock

When applying the status and callback in the response of an operation,
apply them in the same critical section so that there's no race between
checking the callback state and checking status-dependent state (such as
the data version).

Fix this by:

(1) Allocating a joint {status,callback} record (afs_status_cb) before
calling the RPC function for each vnode for which the RPC reply
contains a status or a status plus a callback. A flag is set in the
record to indicate if a callback was actually received.

(2) These records are passed into the RPC functions to be filled in. The
afs_decode_status() and yfs_decode_status() functions are removed and
the cb_lock is no longer taken.

(3) xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() no longer
update the vnode.

(4) xdr_decode_AFSCallBack() and xdr_decode_YFSCallBack() no longer update
the vnode.

(5) vnodes, expected data-version numbers and callback break counters
(cb_break) no longer need to be passed to the reply delivery
functions.

Note that, for the moment, the file locking functions still need
access to both the call and the vnode at the same time.

(6) afs_vnode_commit_status() is now given the cb_break value and the
expected data_version and the task of applying the status and the
callback to the vnode are now done here.

This is done under a single taking of vnode->cb_lock.

(7) afs_pages_written_back() is now called by afs_store_data() rather than
by the reply delivery function.

afs_pages_written_back() has been moved to before the call point and
is now given the first and last page numbers rather than a pointer to
the call.

(8) The indicator from YFS.RemoveFile2 as to whether the target file
actually got removed (status.abort_code == VNOVNODE) rather than
merely dropping a link is now checked in afs_unlink rather than in
xdr_decode_YFSFetchStatus().

Supplementary fixes:

(*) afs_cache_permit() now gets the caller_access mask from the
afs_status_cb object rather than picking it out of the vnode's status
record. afs_fetch_status() returns caller_access through its argument
list for this purpose also.

(*) afs_inode_init_from_status() now uses a write lock on cb_lock rather
than a read lock and now sets the callback inside the same critical
section.

Fixes: c435ee34551e ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Always get the reply time

Always ask for the reply time from AF_RXRPC as it's used to calculate the
callback expiry time and lock expiry times, so it's needed by most FS
operations.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix order-1 allocation in afs_do_lookup()

afs_do_lookup() will do an order-1 allocation to allocate status records if
there are more than 39 vnodes to stat.

Fix this by allocating an array of {status,callback} records for each vnode
we want to examine using vmalloc() if larger than a page.

This not only gets rid of the order-1 allocation, but makes it easier to
grow beyond 50 records for YFS servers. It also allows us to move to
{status,callback} tuples for other calls too and makes it easier to lock
across the application of the status and the callback to the vnode.

Fixes: 5cf9dd55a0ec ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix calculation of callback expiry time

Fix the calculation of the expiry time of a callback promise, as obtained
from operations like FS.FetchStatus and FS.FetchData.

The time should be based on the timestamp of the first DATA packet in the
reply and the calculation needs to turn the ktime_t timestamp into a
time64_t.

Fixes: c435ee34551e ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Get rid of afs_call::reply[]

Replace the afs_call::reply[] array with a bunch of typed members so that
the compiler can use type-checking on them. It's also easier for the eye
to see what's going on.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Don't pass the vnode pointer through into the inline bulk status op

Don't pass the vnode pointer through into the inline bulk status op. We
want to process the status records outside of it anyway.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Make some RPC operations non-interruptible

Make certain RPC operations non-interruptible, including:

(*) Set attributes
(*) Store data

We don't want to get interrupted during a flush on close, flush on
unlock, writeback or an inode update, leaving us in a state where we
still need to do the writeback or update.

(*) Extend lock
(*) Release lock

We don't want to get lock extension interrupted as the file locks on
the server are time-limited. Interruption during lock release is less
of an issue since the lock is time-limited, but it's better to
complete the release to avoid a several-minute wait to recover it.

*Setting* the lock isn't a problem if it's interrupted since we can
just return to the user and tell them they were interrupted - at
which point they can elect to retry.

(*) Silly unlink

We want to remove silly unlink files if we can, rather than leaving
them for the salvager to clear up.

Note that whilst these calls are no longer interruptible, they do have
timeouts on them, so if the server stops responding the call will fail with
something like ETIME or ECONNRESET.

Without this, the following:

kAFS: Unexpected error from FS.StoreData -512

appears in dmesg when a pending store data gets interrupted and some
processes may just hang.

Additionally, make the code that checks/updates the server record ignore
failure due to interruption if the main call is uninterruptible and if the
server has an address list. The next op will check it again since the
expiration time on the old list has past.

Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Fix afs_xattr_get_yfs() to not try freeing an error value

afs_xattr_get_yfs() tries to free yacl, which may hold an error value (say
if yfs_fs_fetch_opaque_acl() failed and returned an error).

Fix this by allocating yacl up front (since it's a fixed-length struct,
unlike afs_acl) and passing it in to the RPC function. This also allows
the flags to be placed in the object rather than passing them through to
the RPC function.

Fixes: ae46578b963f ("afs: Get YFS ACLs and information through xattrs")
Signed-off-by: David Howells <dhowells@redhat.com>

afs: Implement YFS ACL setting

Implement the setting of YFS ACLs in AFS through the interface of setting
the afs.yfs.acl extended attribute on the file.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Get YFS ACLs and information through xattrs

The YFS/AuriStor variant of AFS provides more capable ACLs and provides
per-volume ACLs and per-file ACLs as well as per-directory ACLs. It also
provides some extra information that can be retrieved through four ACLs:

(1) afs.yfs.acl

The YFS file ACL (not the same format as afs.acl).

(2) afs.yfs.vol_acl

The YFS volume ACL.

(3) afs.yfs.acl_inherited

"1" if a file's ACL is inherited from its parent directory, "0"
otherwise.

(4) afs.yfs.acl_num_cleaned

The number of of ACEs removed from the ACL by the server because the
PT entries were removed from the PTS database (ie. the subject is no
longer known).

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Provide mount-time configurable byte-range file locking emulation

Provide byte-range file locking emulation that can be configured at mount
time to one of four modes:

(1) flock=local. Locking is done locally only and no reference is made to
the server.

(2) flock=openafs. Byte-range locking is done locally only; whole-file
locking is done with reference to the server. Whole-file locks cannot
be upgraded unless the client holds an exclusive lock.

(3) flock=strict. Byte-range and whole-file locking both require a
sufficient whole-file lock on the server.

(4) flock=write. As strict, but the client always gets an exclusive
whole-file lock on the server.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Add more tracepoints

Add four more tracepoints:

(1) afs_make_fs_call1 - Split from afs_make_fs_call but takes a filename
to log also.

(2) afs_make_fs_call2 - Like the above but takes two filenames to log.

(3) afs_lookup - Log the result of doing a successful lookup, including a
negative result (fid 0:0).

(4) afs_get_tree - Log the set up of a volume for mounting.

It also extends the name buffer on the afs_edit_dir tracepoint to 24 chars
and puts quotes around the filename in the text representation.

Signed-off-by: David Howells <dhowells@redhat.com>

afs: Calculate lock extend timer from set/extend reply reception

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>

afs: Split wait from afs_make_call()

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>

afs: Mark expected switch fall-throughs

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>

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: 31143d5d515e ("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>

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: 30062bd13e36 ("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>

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: 68251f0a6818 ("afs: Fix whole-volume callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>

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>