linux.git/fs/afs/file.c, branch v5.2

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

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 license as published by
  the free software foundation either version 2 of the license 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 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

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

2019-05-16T15:25:21+00:00

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

afs: Get rid of afs_call::reply[]

2019-05-16T15:25:21+00:00

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

afs: Make some RPC operations non-interruptible

2019-05-16T15:25:20+00:00

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
Reported-by: Marc Dionne
Signed-off-by: David Howells

afs: Fix key leak in afs_release() and afs_evict_inode()

2019-05-15T11:32:34+00:00

Fix afs_release() to go through the cleanup part of the function if
FMODE_WRITE is set rather than exiting through vfs_fsync() (which skips the
cleanup).  The cleanup involves discarding the refs on the key used for
file ops and the writeback key record.

Also fix afs_evict_inode() to clean up any left over wb keys attached to
the inode/vnode when it is removed.

Fixes: 5a8132761609 ("afs: Do better accretion of small writes on newly created content")
Signed-off-by: David Howells

afs: Mark expected switch fall-throughs

2019-04-08T23:35:56+00:00

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 
Signed-off-by: Gustavo A. R. Silva

fs: don't open code lru_to_page()

2019-01-04T21:13:48+00:00

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 
Acked-by: Michal Hocko 
Reviewed-by: David Hildenbrand 
Reviewed-by: Mike Rapoport 
Acked-by: Pankaj gupta 
Acked-by: "Yan, Zheng" 		[ceph]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS

2018-10-23T23:41:08+00:00

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

afs: Fix whole-volume callback handling

2018-05-14T14:15:18+00:00

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: c435ee34551e ("afs: Overhaul the callback handling")
Signed-off-by: David Howells

afs: Do better accretion of small writes on newly created content

2018-04-09T20:54:48+00:00

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