smb: client: fix rename(2) regression against samba

After commit 2c7d399e551c ("smb: client: reuse file lease key in
compound operations") the client started reusing lease keys for
rename, unlink and set path size operations to prevent it from
breaking its own leases and thus causing unnecessary lease breaks to
same connection.

The implementation relies on positive dentries and
cifsInodeInfo::lease_granted to decide whether reusing lease keys for
the compound requests. cifsInodeInfo::lease_granted was introduced by
commit 0ab95c2510b6 ("Defer close only when lease is enabled.") to
indicate whether lease caching is granted for a specific file, but
that can only happen until file is open, so
cifsInodeInfo::lease_granted was left uninitialised in ->alloc_inode
and then client started sending random lease keys for files that
hadn't any leases.

This fixes the following test case against samba:

mount.cifs //srv/share /mnt/1 -o ...,nosharesock
mount.cifs //srv/share /mnt/2 -o ...,nosharesock
touch /mnt/1/foo; tail -f /mnt/1/foo & pid=$!
mv /mnt/2/foo /mnt/2/bar # fails with -EIO
kill $pid

Fixes: 0ab95c2510b6 ("Defer close only when lease is enabled.")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: Add tracing for the cifs_tcon struct refcounting

Add tracing for the refcounting/lifecycle of the cifs_tcon struct, marking
different events with different labels and giving each tcon its own debug
ID so that the tracelines corresponding to individual tcons can be
distinguished. This can be enabled with:

echo 1 >/sys/kernel/debug/tracing/events/cifs/smb3_tcon_ref/enable

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

smb3: retrying on failed server close

In the current implementation, CIFS close sends a close to the
server and does not check for the success of the server close.
This patch adds functionality to check for server close return
status and retries in case of an EBUSY or EAGAIN error.

This can help avoid handle leaks

Cc: stable@vger.kernel.org
Signed-off-by: Ritvik Budhiraja <rbudhiraja@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: Move some extern decls from .c files to .h

Move the following:

extern mempool_t *cifs_sm_req_poolp;
extern mempool_t *cifs_req_poolp;
extern mempool_t *cifs_mid_poolp;
extern bool disable_legacy_dialects;

from various .c files to cifsglob.h.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

smb: client: return reparse type in /proc/mounts

Add support for returning reparse mount option in /proc/mounts.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202402262152.YZOwDlCM-lkp@intel.com/
Signed-off-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb: remove SLAB_MEM_SPREAD flag usage

The SLAB_MEM_SPREAD flag is already a no-op as of 6.8-rc1, remove
its usage so we can delete it from slab. No functional change.

Link: https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-0-02f1753e8303@suse.cz/

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

mm, slab: remove last vestiges of SLAB_MEM_SPREAD

Yes, yes, I know the slab people were planning on going slow and letting
every subsystem fight this thing on their own. But let's just rip off
the band-aid and get it over and done with. I don't want to see a
number of unnecessary pull requests just to get rid of a flag that no
longer has any meaning.

This was mainly done with a couple of 'sed' scripts and then some manual
cleanup of the end result.

Link: https://lore.kernel.org/all/CAHk-=wji0u+OOtmAOD-5JV3SXcRJF___k_+8XNKmak0yd5vW1Q@mail.gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

smb: remove redundant check

->setlease() is never called on non-regular files now. So remove the
check from cifs_setlease().

Link: https://lore.kernel.org/r/170716318935.13976.13465352731929804157@noble.neil.brown.name
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

filelock: split leases out of struct file_lock

Add a new struct file_lease and move the lease-specific fields from
struct file_lock to it. Convert the appropriate API calls to take
struct file_lease instead, and convert the callers to use them.

There is zero overlap between the lock manager operations for file
locks and the ones for file leases, so split the lease-related
operations off into a new lease_manager_operations struct.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-47-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

cifs_get_link(): bail out in unsafe case

->d_revalidate() bails out there, anyway. It's not enough
to prevent getting into ->get_link() in RCU mode, but that
could happen only in a very contrieved setup. Not worth
trying to do anything fancy here unless ->d_revalidate()
stops kicking out of RCU mode at least in some cases.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

cifs: Share server EOF pos with netfslib

Use cifsi->netfs_ctx.remote_i_size instead of cifsi->server_eof so that
netfslib can refer to it to.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: new mount option called retrans

We have several places in the code where we treat the
error -EAGAIN very differently. Some code retry for
arbitrary number of times.

Introducing this new mount option named "retrans", so
that all these handlers of -EAGAIN can retry a fixed
number of times. This applies only to soft mounts.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

netfs: Optimise away reads above the point at which there can be no data

Track the file position above which the server is not expected to have any
data (the "zero point") and preemptively assume that we can satisfy
requests by filling them with zeroes locally rather than attempting to
download them if they're over that line - even if we've written data back
to the server. Assume that any data that was written back above that
position is held in the local cache. Note that we have to split requests
that straddle the line.

Make use of this to optimise away some reads from the server. We need to
set the zero point in the following circumstances:

(1) When we see an extant remote inode and have no cache for it, we set
the zero_point to i_size.

(2) On local inode creation, we set zero_point to 0.

(3) On local truncation down, we reduce zero_point to the new i_size if
the new i_size is lower.

(4) On local truncation up, we don't change zero_point.

(5) On local modification, we don't change zero_point.

(6) On remote invalidation, we set zero_point to the new i_size.

(7) If stored data is discarded from the pagecache or culled from fscache,
we must set zero_point above that if the data also got written to the
server.

(8) If dirty data is written back to the server, but not fscache, we must
set zero_point above that.

(9) If a direct I/O write is made, set zero_point above that.

Assuming the above, any read from the server at or above the zero_point
position will return all zeroes.

The zero_point value can be stored in the cache, provided the above rules
are applied to it by any code that culls part of the local cache.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org

netfs: Move pinning-for-writeback from fscache to netfs

Move the resource pinning-for-writeback from fscache code to netfslib code.
This is used to keep a cache backing object pinned whilst we have dirty
pages on the netfs inode in the pagecache such that VM writeback will be
able to reach it.

Whilst we're at it, switch the parameters of netfs_unpin_writeback() to
match ->write_inode() so that it can be used for that directly.

Note that this mechanism could be more generically useful than that for
network filesystems. Quite often they have to keep around other resources
(e.g. authentication tokens or network connections) until the writeback is
complete.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org

fs: use splice_copy_file_range() inline helper

generic_copy_file_range() is just a wrapper around splice_file_range(),
which caps the maximum copy length.

The only caller of splice_file_range(), namely __ceph_copy_file_range()
is already ready to cope with short copy.

Move the length capping into splice_file_range() and replace the exported
symbol generic_copy_file_range() with a simple inline helper.

Suggested-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/linux-fsdevel/20231204083849.GC32438@lst.de/
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231212094440.250945-3-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

cifs: Fix non-availability of dedup breaking generic/304

Deduplication isn't supported on cifs, but cifs doesn't reject it, instead
treating it as extent duplication/cloning. This can cause generic/304 to go
silly and run for hours on end.

Fix cifs to indicate EOPNOTSUPP if REMAP_FILE_DEDUP is set in
->remap_file_range().

Note that it's unclear whether or not commit b073a08016a1 is meant to cause
cifs to return an error if REMAP_FILE_DEDUP.

Fixes: b073a08016a1 ("cifs: fix that return -EINVAL when do dedupe operation")
Cc: stable@vger.kernel.org
Suggested-by: Dave Chinner <david@fromorbit.com>
cc: Xiaoli Feng <fengxiaoli0714@gmail.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: Darrick Wong <darrick.wong@oracle.com>
cc: fstests@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/3876191.1701555260@warthog.procyon.org.uk/
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: Fix flushing, invalidation and file size with FICLONE

Fix a number of issues in the cifs filesystem implementation of the FICLONE
ioctl in cifs_remap_file_range(). This is analogous to the previously
fixed bug in cifs_file_copychunk_range() and can share the helper
functions.

Firstly, the invalidation of the destination range is handled incorrectly:
We shouldn't just invalidate the whole file as dirty data in the file may
get lost and we can't just call truncate_inode_pages_range() to invalidate
the destination range as that will erase parts of a partial folio at each
end whilst invalidating and discarding all the folios in the middle. We
need to force all the folios covering the range to be reloaded, but we
mustn't lose dirty data in them that's not in the destination range.

Further, we shouldn't simply round out the range to PAGE_SIZE at each end
as cifs should move to support multipage folios.

Secondly, there's an issue whereby a write may have extended the file
locally, but not have been written back yet. This can leaves the local
idea of the EOF at a later point than the server's EOF. If a clone request
is issued, this will fail on the server with STATUS_INVALID_VIEW_SIZE
(which gets translated to -EIO locally) if the clone source extends past
the server's EOF.

Fix this by:

(0) Flush the source region (already done). The flush does nothing and
the EOF isn't moved if the source region has no dirty data.

(1) Move the EOF to the end of the source region if it isn't already at
least at this point. If we can't do this, for instance if the server
doesn't support it, just flush the entire source file.

(2) Find the folio (if present) at each end of the range, flushing it and
increasing the region-to-be-invalidated to cover those in their
entirety.

(3) Fully discard all the folios covering the range as we want them to be
reloaded.

(4) Then perform the extent duplication.

Thirdly, set i_size after doing the duplicate_extents operation as this
value may be used by various things internally. stat() hides the issue
because setting ->time to 0 causes cifs_getatr() to revalidate the
attributes.

These were causing the cifs/001 xfstest to fail.

Fixes: 04b38d601239 ("vfs: pull btrfs clone API to vfs layer")
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
cc: Christoph Hellwig <hch@lst.de>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: Fix flushing, invalidation and file size with copy_file_range()

Fix a number of issues in the cifs filesystem implementation of the
copy_file_range() syscall in cifs_file_copychunk_range().

Firstly, the invalidation of the destination range is handled incorrectly:
We shouldn't just invalidate the whole file as dirty data in the file may
get lost and we can't just call truncate_inode_pages_range() to invalidate
the destination range as that will erase parts of a partial folio at each
end whilst invalidating and discarding all the folios in the middle. We
need to force all the folios covering the range to be reloaded, but we
mustn't lose dirty data in them that's not in the destination range.

Further, we shouldn't simply round out the range to PAGE_SIZE at each end
as cifs should move to support multipage folios.

Secondly, there's an issue whereby a write may have extended the file
locally, but not have been written back yet. This can leaves the local
idea of the EOF at a later point than the server's EOF. If a copy request
is issued, this will fail on the server with STATUS_INVALID_VIEW_SIZE
(which gets translated to -EIO locally) if the copy source extends past the
server's EOF.

Fix this by:

(0) Flush the source region (already done). The flush does nothing and
the EOF isn't moved if the source region has no dirty data.

(1) Move the EOF to the end of the source region if it isn't already at
least at this point. If we can't do this, for instance if the server
doesn't support it, just flush the entire source file.

(2) Find the folio (if present) at each end of the range, flushing it and
increasing the region-to-be-invalidated to cover those in their
entirety.

(3) Fully discard all the folios covering the range as we want them to be
reloaded.

(4) Then perform the copy.

Thirdly, set i_size after doing the copychunk_range operation as this value
may be used by various things internally. stat() hides the issue because
setting ->time to 0 causes cifs_getatr() to revalidate the attributes.

These were causing the generic/075 xfstest to fail.

Fixes: 620d8745b35d ("Introduce cifs_copy_file_range()")
Cc: stable@vger.kernel.org
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb3: fix touch -h of symlink

For example:
touch -h -t 02011200 testfile
where testfile is a symlink would not change the timestamp, but
touch -t 02011200 testfile
does work to change the timestamp of the target

Suggested-by: David Howells <dhowells@redhat.com>
Reported-by: Micah Veilleux <micah.veilleux@iba-group.com>
Closes: https://bugzilla.samba.org/show_bug.cgi?id=14476
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>

smb3: allow controlling maximum number of cached directories

Allow adjusting the maximum number of cached directories per share
(defaults to 16) via mount parm "max_cached_dirs"

Signed-off-by: Steve French <stfrench@microsoft.com>

smb3: allow controlling length of time directory entries are cached with dir leases

Currently with directory leases we cache directory contents for a fixed period
of time (default 30 seconds) but for many workloads this is too short. Allow
configuring the maximum amount of time directory entries are cached when a
directory lease is held on that directory. Add module load parm "max_dir_cache"

For example to set the timeout to 10 minutes you would do:

echo 600 > /sys/module/cifs/parameters/dir_cache_timeout

or to disable caching directory contents:

echo 0 > /sys/module/cifs/parameters/dir_cache_timeout

Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb: client: get rid of dfs naming in automount code

Automount code will handle both DFS links and reparse mount points.

Also, get rid of BUG_ON() in cifs_release_automount_timer() while
we're at it.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs: Pass argument to fcntl_setlease as int

The interface for fcntl expects the argument passed for the command
F_SETLEASE to be of type int. The current code wrongly treats it as
a long. In order to avoid access to undefined bits, we should explicitly
cast the argument to int.

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Kevin Brodsky <Kevin.Brodsky@arm.com>
Cc: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Cc: Szabolcs Nagy <Szabolcs.Nagy@arm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: David Laight <David.Laight@ACULAB.com>
Cc: Mark Rutland <Mark.Rutland@arm.com>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: linux-nfs@vger.kernel.org
Cc: linux-morello@op-lists.linaro.org
Signed-off-by: Luca Vizzarro <Luca.Vizzarro@arm.com>
Message-Id: <20230414152459.816046-3-Luca.Vizzarro@arm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

smb: client: fix warning in cifs_smb3_do_mount()

This fixes the following warning reported by kernel test robot

fs/smb/client/cifsfs.c:982 cifs_smb3_do_mount() warn: possible
memory leak of 'cifs_sb'

Link: https://lore.kernel.org/all/202306170124.CtQqzf0I-lkp@intel.com/
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: print nosharesock value while dumping mount options

We print most other mount options for a mount when dumping
the mount entries. But miss out the nosharesock value.
This change will print that in addition to the other options.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb: move client and server files to common directory fs/smb

Move CIFS/SMB3 related client and server files (cifs.ko and ksmbd.ko
and helper modules) to new fs/smb subdirectory:

fs/cifs --> fs/smb/client
fs/ksmbd --> fs/smb/server
fs/smbfs_common --> fs/smb/common

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>