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Merge tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull mmap_prepare updates from Christian Brauner:
"Last cycle we introduce f_op->mmap_prepare() in c84bf6dd2b ("mm:
introduce new .mmap_prepare() file callback").
This is preferred to the existing f_op->mmap() hook as it does require
a VMA to be established yet, thus allowing the mmap logic to invoke
this hook far, far earlier, prior to inserting a VMA into the virtual
address space, or performing any other heavy handed operations.
This allows for much simpler unwinding on error, and for there to be a
single attempt at merging a VMA rather than having to possibly
reattempt a merge based on potentially altered VMA state.
Far more importantly, it prevents inappropriate manipulation of
incompletely initialised VMA state, which is something that has been
the cause of bugs and complexity in the past.
The intent is to gradually deprecate f_op->mmap, and in that vein this
series coverts the majority of file systems to using f_op->mmap_prepare.
Prerequisite steps are taken - firstly ensuring all checks for mmap
capabilities use the file_has_valid_mmap_hooks() helper rather than
directly checking for f_op->mmap (which is now not a valid check) and
secondly updating daxdev_mapping_supported() to not require a VMA
parameter to allow ext4 and xfs to be converted.
Commit bb666b7c27 ("mm: add mmap_prepare() compatibility layer for
nested file systems") handles the nasty edge-case of nested file
systems like overlayfs, which introduces a compatibility shim to allow
f_op->mmap_prepare() to be invoked from an f_op->mmap() callback.
This allows for nested filesystems to continue to function correctly
with all file systems regardless of which callback is used. Once we
finally convert all file systems, this shim can be removed.
As a result, ecryptfs, fuse, and overlayfs remain unaltered so they
can nest all other file systems.
We additionally do not update resctl - as this requires an update to
remap_pfn_range() (or an alternative to it) which we defer to a later
series, equally we do not update cramfs which needs a mixed mapping
insertion with the same issue, nor do we update procfs, hugetlbfs,
syfs or kernfs all of which require VMAs for internal state and hooks.
We shall return to all of these later"
* tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
doc: update porting, vfs documentation to describe mmap_prepare()
fs: replace mmap hook with .mmap_prepare for simple mappings
fs: convert most other generic_file_*mmap() users to .mmap_prepare()
fs: convert simple use of generic_file_*_mmap() to .mmap_prepare()
mm/filemap: introduce generic_file_*_mmap_prepare() helpers
fs/xfs: transition from deprecated .mmap hook to .mmap_prepare
fs/ext4: transition from deprecated .mmap hook to .mmap_prepare
fs/dax: make it possible to check dev dax support without a VMA
fs: consistently use can_mmap_file() helper
mm/nommu: use file_has_valid_mmap_hooks() helper
mm: rename call_mmap/mmap_prepare to vfs_mmap/mmap_prepare
Update nearly all generic_file_mmap() and generic_file_readonly_mmap()
callers to use generic_file_mmap_prepare() and
generic_file_readonly_mmap_prepare() respectively.
We update blkdev, 9p, afs, erofs, ext2, nfs, ntfs3, smb, ubifs and vboxsf
file systems this way.
Remaining users we cannot yet update are ecryptfs, fuse and cramfs. The
former two are nested file systems that must support any underlying file
ssytem, and cramfs inserts a mixed mapping which currently requires a VMA.
Once all file systems have been converted to mmap_prepare(), we can then
update nested file systems.
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Link: https://lore.kernel.org/08db85970d89b17a995d2cffae96fb4cc462377f.1750099179.git.lorenzo.stoakes@oracle.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
... to be used instead of manually assigning to ->s_d_op.
All in-tree filesystem converted (and field itself is renamed,
so any out-of-tree ones in need of conversion will be caught
by compiler).
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'v6.16-rc-part1-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client updates from Steve French:
- multichannel fixes (mostly reconnect related), and clarification of
locking documentation
- automount null pointer check fix
- fixes to add support for ParentLeaseKey
- minor cleanup
- smb1/cifs fixes
* tag 'v6.16-rc-part1-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: update the lock ordering comments with new mutex
cifs: dns resolution is needed only for primary channel
cifs: update dstaddr whenever channel iface is updated
cifs: reset connections for all channels when reconnect requested
smb: client: use ParentLeaseKey in cifs_do_create
smb: client: use ParentLeaseKey in open_cached_dir
smb: client: add ParentLeaseKey support
cifs: Fix cifs_query_path_info() for Windows NT servers
cifs: Fix validation of SMB1 query reparse point response
cifs: Correctly set SMB1 SessionKey field in Session Setup Request
cifs: Fix encoding of SMB1 Session Setup NTLMSSP Request in non-UNICODE mode
smb: client: add NULL check in automount_fullpath
smb: client: Remove an unused function and variable
SMB2_QFS_info() has been unused since 2018's
commit 730928c8f4 ("cifs: update smb2_queryfs() to use compounding")
sign_CIFS_PDUs has been unused since 2009's
commit 2edd6c5b05 ("[CIFS] NTLMSSP support moving into new file, old dead
code removed")
Remove them.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
The lookup_one_len family of functions is (now) only used internally by
a filesystem on itself either
- in a context where permission checking is irrelevant such as by a
virtual filesystem populating itself, or xfs accessing its ORPHANAGE
or dquota accessing the quota file; or
- in a context where a permission check (MAY_EXEC on the parent) has just
been performed such as a network filesystem finding in "silly-rename"
file in the same directory. This is also the context after the
_parentat() functions where currently lookup_one_qstr_excl() is used.
So the permission check is pointless.
The name "one_len" is unhelpful in understanding the purpose of these
functions and should be changed. Most of the callers pass the len as
"strlen()" so using a qstr and QSTR() can simplify the code.
This patch renames these functions (include lookup_positive_unlocked()
which is part of the family despite the name) to have a name based on
"lookup_noperm". They are changed to receive a 'struct qstr' instead
of separate name and len. In a few cases the use of QSTR() results in a
new call to strlen().
try_lookup_noperm() takes a pointer to a qstr instead of the whole
qstr. This is consistent with d_hash_and_lookup() (which is nearly
identical) and useful for lookup_noperm_unlocked().
The new lookup_noperm_common() doesn't take a qstr yet. That will be
tidied up in a subsequent patch.
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://lore.kernel.org/r/20250319031545.2999807-5-neil@brown.name
Signed-off-by: Christian Brauner <brauner@kernel.org>
SMB1 protocol supports non-UNICODE (8-bit OEM character set) and
UNICODE (UTF-16) modes.
Linux SMB1 client implements both of them but currently does not allow to
choose non-UNICODE mode when SMB1 server announce UNICODE mode support.
This change adds a new mount option -o nounicode to disable UNICODE mode
and force usage of non-UNICODE (8-bit OEM character set) mode.
This allows to test non-UNICODE implementation of Linux SMB1 client against
any SMB1 server, including modern and recent Windows SMB1 server.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Native Windows sockets created by WinSock on Windows 10 April 2018 Update
(version 1803) or Windows Server 2019 (version 1809) or later versions is
reparse point with IO_REPARSE_TAG_AF_UNIX tag, with empty reparse point
data buffer and without any EAs.
Create AF_UNIX sockets in this native format if -o nonativesocket was not
specified.
This change makes AF_UNIX sockets created by Linux CIFS client compatible
with AF_UNIX sockets created by Windows applications on NTFS volumes.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently Linux CIFS client creates a new symlink of the first flavor which
is allowed by mount options, parsed in this order: -o (no)mfsymlinks,
-o (no)sfu, -o (no)unix (+ its aliases) and -o reparse=[type].
Introduce a new mount option -o symlink= for explicitly choosing a symlink
flavor. Possible options are:
-o symlink=default - The default behavior, like before this change.
-o symlink=none - Disallow creating a new symlinks
-o symlink=native - Create as native SMB symlink reparse point
-o symlink=unix - Create via SMB1 unix extension command
-o symlink=mfsymlinks - Create as regular file of mfsymlinks format
-o symlink=sfu - Create as regular system file of SFU format
-o symlink=nfs - Create as NFS reparse point
-o symlink=wsl - Create as WSL reparse point
So for example specifying -o sfu,mfsymlinks,symlink=native will allow to
parse symlinks also of SFU and mfsymlinks types (which are disabled by
default unless mount option is explicitly specified), but new symlinks will
be created under native SMB type (which parsing is always enabled).
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Replace default hardcoded value for cifsAttrs with ATTR_ARCHIVE macro
Use SMB2_LEASE_KEY_SIZE macro for leasekey size in smb2_lease_break
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The unmount process (cifs_kill_sb() calling close_all_cached_dirs()) can
race with various cached directory operations, which ultimately results
in dentries not being dropped and these kernel BUGs:
BUG: Dentry ffff88814f37e358{i=1000000000080,n=/} still in use (2) [unmount of cifs cifs]
VFS: Busy inodes after unmount of cifs (cifs)
------------[ cut here ]------------
kernel BUG at fs/super.c:661!
This happens when a cfid is in the process of being cleaned up when, and
has been removed from the cfids->entries list, including:
- Receiving a lease break from the server
- Server reconnection triggers invalidate_all_cached_dirs(), which
removes all the cfids from the list
- The laundromat thread decides to expire an old cfid.
To solve these problems, dropping the dentry is done in queued work done
in a newly-added cfid_put_wq workqueue, and close_all_cached_dirs()
flushes that workqueue after it drops all the dentries of which it's
aware. This is a global workqueue (rather than scoped to a mount), but
the queued work is minimal.
The final cleanup work for cleaning up a cfid is performed via work
queued in the serverclose_wq workqueue; this is done separate from
dropping the dentries so that close_all_cached_dirs() doesn't block on
any server operations.
Both of these queued works expect to invoked with a cfid reference and
a tcon reference to avoid those objects from being freed while the work
is ongoing.
While we're here, add proper locking to close_all_cached_dirs(), and
locking around the freeing of cfid->dentry.
Fixes: ebe98f1447 ("cifs: enable caching of directories for which a lease is held")
Cc: stable@vger.kernel.org
Signed-off-by: Paul Aurich <paul@darkrain42.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
In the current implementation, the SMB filesystem on a mount point can
trigger upcalls from the kernel to the userspace to enable certain
functionalities like spnego, dns_resolution, amongst others. These upcalls
usually either happen in the context of the mount or in the context of an
application/user. The upcall handler for cifs, cifs.upcall already has
existing code which switches the namespaces to the caller's namespace
before handling the upcall. This behaviour is expected for scenarios like
multiuser mounts, but might not cover all single user scenario with
services such as Kubernetes, where the mount can happen from different
locations such as on the host, from an app container, or a driver pod
which does the mount on behalf of a different pod.
This patch introduces a new mount option called upcall_target, to
customise the upcall behaviour. upcall_target can take 'mount' and 'app'
as possible values. This aids use cases like Kubernetes where the mount
happens on behalf of the application in another container altogether.
Having this new mount option allows the mount command to specify where the
upcall should happen: 'mount' for resolving the upcall to the host
namespace, and 'app' for resolving the upcall to the ns of the calling
thread. This will enable both the scenarios where the Kerberos credentials
can be found on the application namespace or the host namespace to which
just the mount operation is "delegated".
Reviewed-by: Shyam Prasad <shyam.prasad@microsoft.com>
Reviewed-by: Bharath S M <bharathsm@microsoft.com>
Reviewed-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Signed-off-by: Ritvik Budhiraja <rbudhiraja@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
There's a issue as follows:
WARNING: CPU: 1 PID: 27826 at mm/slub.c:4698 free_large_kmalloc+0xac/0xe0
RIP: 0010:free_large_kmalloc+0xac/0xe0
Call Trace:
<TASK>
? __warn+0xea/0x330
mempool_destroy+0x13f/0x1d0
init_cifs+0xa50/0xff0 [cifs]
do_one_initcall+0xdc/0x550
do_init_module+0x22d/0x6b0
load_module+0x4e96/0x5ff0
init_module_from_file+0xcd/0x130
idempotent_init_module+0x330/0x620
__x64_sys_finit_module+0xb3/0x110
do_syscall_64+0xc1/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Obviously, 'cifs_io_request_pool' is not created by mempool_create().
So just use mempool_exit() to revert 'cifs_io_request_pool'.
Fixes: edea94a697 ("cifs: Add mempools for cifs_io_request and cifs_io_subrequest structs")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Acked-by: David Howells <dhowells@redhat.com
Signed-off-by: Steve French <stfrench@microsoft.com>
Due to server permission control, the client does not have access to
the shared root directory, but can access subdirectories normally, so
users usually mount the shared subdirectories directly. In this case,
queryfs should use the actual path instead of the root directory to
avoid the call returning an error (EACCES).
Signed-off-by: wangrong <wangrong@uniontech.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix cifs_file_copychunk_range() to flush the destination region before
invalidating it to avoid potential loss of data should the copy fail, in
whole or in part, in some way.
Fixes: 7b2404a886 ("cifs: Fix flushing, invalidation and file size with copy_file_range()")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.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
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
The comments have typos, fix that to not confuse readers.
Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Dan Carpenter reported a Smack static checker warning:
fs/smb/client/cifsfs.c:1981 init_cifs()
error: we previously assumed 'serverclose_wq' could be null (see line 1895)
The patch which introduced the serverclose workqueue used the wrong
oredering in error paths in init_cifs() for freeing it on errors.
Fixes: 173217bd73 ("smb3: retrying on failed server close")
Cc: stable@vger.kernel.org
Cc: Ritvik Budhiraja <rbudhiraja@microsoft.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: David Howells <dhowell@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
There are common cases where copy_file_range can noisily
log "source and target of copy not on same server"
e.g. the mv command across mounts to two different server's shares.
Change this to informational rather than logging as an error.
A followon patch will add dynamic trace points e.g. for
cifs_file_copychunk_range
Cc: stable@vger.kernel.org
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
enable_gcm_256 (which allows the server to require the strongest
encryption) is enabled by default, but the modinfo description
incorrectly showed it disabled by default. Fix the typo.
Cc: stable@vger.kernel.org
Fixes: fee742b502 ("smb3.1.1: enable negotiating stronger encryption by default")
Signed-off-by: Steve French <stfrench@microsoft.com>
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Merge tag 'vfs-6.10-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
- Fix io_uring based write-through after converting cifs to use the
netfs library
- Fix aio error handling when doing write-through via netfs library
- Fix performance regression in iomap when used with non-large folio
mappings
- Fix signalfd error code
- Remove obsolete comment in signalfd code
- Fix async request indication in netfs_perform_write() by raising
BDP_ASYNC when IOCB_NOWAIT is set
- Yield swap device immediately to prevent spurious EBUSY errors
- Don't cross a .backup mountpoint from backup volumes in afs to avoid
infinite loops
- Fix a race between umount and async request completion in 9p after 9p
was converted to use the netfs library
* tag 'vfs-6.10-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
netfs, 9p: Fix race between umount and async request completion
afs: Don't cross .backup mountpoint from backup volume
swap: yield device immediately
netfs: Fix setting of BDP_ASYNC from iocb flags
signalfd: drop an obsolete comment
signalfd: fix error return code
iomap: fault in smaller chunks for non-large folio mappings
filemap: add helper mapping_max_folio_size()
netfs: Fix AIO error handling when doing write-through
netfs: Fix io_uring based write-through
Occasionally, the generic/001 xfstest will fail indicating corruption in
one of the copy chains when run on cifs against a server that supports
FSCTL_DUPLICATE_EXTENTS_TO_FILE (eg. Samba with a share on btrfs). The
problem is that the remote_i_size value isn't updated by cifs_setsize()
when called by smb2_duplicate_extents(), but i_size *is*.
This may cause cifs_remap_file_range() to then skip the bit after calling
->duplicate_extents() that sets sizes.
Fix this by calling netfs_resize_file() in smb2_duplicate_extents() before
calling cifs_setsize() to set i_size.
This means we don't then need to call netfs_resize_file() upon return from
->duplicate_extents(), but we also fix the test to compare against the pre-dup
inode size.
[Note that this goes back before the addition of remote_i_size with the
netfs_inode struct. It should probably have been setting cifsi->server_eof
previously.]
Fixes: cfc63fc812 ("smb3: fix cached file size problems in duplicate extents (reflink)")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.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: netfs@lists.linux.dev
Signed-off-by: Steve French <stfrench@microsoft.com>
insmod followed by rmmod was oopsing with the new mempools cifs request patch
Fixes: edea94a697 ("cifs: Add mempools for cifs_io_request and cifs_io_subrequest structs")
Suggested-by: David Howells <dhowells@redhat.com>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Make the cifs filesystem use netfslib to handle reading and writing on
behalf of cifs. The changes include:
(1) Various read_iter/write_iter type functions are turned into wrappers
around netfslib API functions or are pointed directly at those
functions:
cifs_file_direct{,_nobrl}_ops switch to use
netfs_unbuffered_read_iter and netfs_unbuffered_write_iter.
Large pieces of code that will be removed are #if'd out and will be removed
in subsequent patches.
[?] Why does cifs mark the page dirty in the destination buffer of a DIO
read? Should that happen automatically? Does netfs need to do that?
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
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: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Provide implementation of the netfslib hooks that will be used by netfslib
to ask cifs to set up and perform operations. Of particular note are
(*) cifs_clamp_length() - This is used to negotiate the size of the next
subrequest in a read request, taking into account the credit available
and the rsize. The credits are attached to the subrequest.
(*) cifs_req_issue_read() - This is used to issue a subrequest that has
been set up and clamped.
(*) cifs_prepare_write() - This prepares to fill a subrequest by picking a
channel, reopening the file and requesting credits so that we can set
the maximum size of the subrequest and also sets the maximum number of
segments if we're doing RDMA.
(*) cifs_issue_write() - This releases any unneeded credits and issues an
asynchronous data write for the contiguous slice of file covered by
the subrequest. This should possibly be folded in to all
->async_writev() ops and that called directly.
(*) cifs_begin_writeback() - This gets the cached writable handle through
which we do writeback (this does not affect writethrough, unbuffered
or direct writes).
At this point, cifs is not wired up to actually *use* netfslib; that will
be done in a subsequent patch.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
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: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Add mempools for the allocation of cifs_io_request and cifs_io_subrequest
structs for netfslib to use so that it can guarantee eventual allocation in
writeback.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
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: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Set zero_point in the copy_file_range() and remap_file_range()
implementations so that we don't skip reading data modified on a
server-side copy.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
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: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Move cifs_loose_read_iter() and cifs_file_write_iter() to file.c so that
they are colocated with similar functions rather than being split with
cifsfs.c.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
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: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
After commit 2c7d399e55 ("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 0ab95c2510 ("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: 0ab95c2510 ("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>
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>
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>
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>
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Merge tag '6.9-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client updates from Steve French:
- fix for folios/netfs data corruption in cifs_extend_writeback
- additional tracepoint added
- updates for special files and symlinks: improvements to allow
selecting use of either WSL or NFS reparse point format on creating
special files
- allocation size improvement for cached files
- minor cleanup patches
- fix to allow changing the password on remount when password for the
session is expired.
- lease key related fixes: caching hardlinked files, deletes of
deferred close files, and an important fix to better reuse lease keys
for compound operations, which also can avoid lease break timeouts
when low on credits
- fix potential data corruption with write/readdir races
- compression cleanups and a fix for compression headers
* tag '6.9-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6: (24 commits)
cifs: update internal module version number for cifs.ko
smb: common: simplify compression headers
smb: common: fix fields sizes in compression_pattern_payload_v1
smb: client: negotiate compression algorithms
smb3: add dynamic trace point for ioctls
cifs: Fix writeback data corruption
smb: client: return reparse type in /proc/mounts
smb: client: set correct d_type for reparse DFS/DFSR and mount point
smb: client: parse uid, gid, mode and dev from WSL reparse points
smb: client: introduce SMB2_OP_QUERY_WSL_EA
smb: client: Fix a NULL vs IS_ERR() check in wsl_set_xattrs()
smb: client: add support for WSL reparse points
smb: client: reduce number of parameters in smb2_compound_op()
smb: client: fix potential broken compound request
smb: client: move most of reparse point handling code to common file
smb: client: introduce reparse mount option
smb: client: retry compound request without reusing lease
smb: client: do not defer close open handles to deleted files
smb: client: reuse file lease key in compound operations
smb3: update allocation size more accurately on write completion
...
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>
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Merge tag 'vfs-6.9.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull file locking updates from Christian Brauner:
"A few years ago struct file_lock_context was added to allow for
separate lists to track different types of file locks instead of using
a singly-linked list for all of them.
Now leases no longer need to be tracked using struct file_lock.
However, a lot of the infrastructure is identical for leases and locks
so separating them isn't trivial.
This splits a group of fields used by both file locks and leases into
a new struct file_lock_core. The new core struct is embedded in struct
file_lock. Coccinelle was used to convert a lot of the callers to deal
with the move, with the remaining 25% or so converted by hand.
Afterwards several internal functions in fs/locks.c are made to work
with struct file_lock_core. Ultimately this allows to split struct
file_lock into struct file_lock and struct file_lease. The file lease
APIs are then converted to take struct file_lease"
* tag 'vfs-6.9.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (51 commits)
filelock: fix deadlock detection in POSIX locking
filelock: always define for_each_file_lock()
smb: remove redundant check
filelock: don't do security checks on nfsd setlease calls
filelock: split leases out of struct file_lock
filelock: remove temporary compatibility macros
smb/server: adapt to breakup of struct file_lock
smb/client: adapt to breakup of struct file_lock
ocfs2: adapt to breakup of struct file_lock
nfsd: adapt to breakup of struct file_lock
nfs: adapt to breakup of struct file_lock
lockd: adapt to breakup of struct file_lock
fuse: adapt to breakup of struct file_lock
gfs2: adapt to breakup of struct file_lock
dlm: adapt to breakup of struct file_lock
ceph: adapt to breakup of struct file_lock
afs: adapt to breakup of struct file_lock
9p: adapt to breakup of struct file_lock
filelock: convert seqfile handling to use file_lock_core
filelock: convert locks_translate_pid to take file_lock_core
...
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>
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>
pathwalk. This series is a result of code audit (the second round
of it) and it should deal with most of that stuff. Exceptions: ntfs3
->d_hash()/->d_compare() and ceph_d_revalidate(). Up to maintainers (a
note for NTFS folks - when documentation says that a method may not block,
it *does* imply that blocking allocations are to be avoided. Really).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull RCU pathwalk fixes from Al Viro:
"We still have some races in filesystem methods when exposed to RCU
pathwalk. This series is a result of code audit (the second round of
it) and it should deal with most of that stuff.
Still pending: ntfs3 ->d_hash()/->d_compare() and ceph_d_revalidate().
Up to maintainers (a note for NTFS folks - when documentation says
that a method may not block, it *does* imply that blocking allocations
are to be avoided. Really)"
[ More explanations for people who aren't familiar with the vagaries of
RCU path walking: most of it is hidden from filesystems, but if a
filesystem actively participates in the low-level path walking it
needs to make sure the fields involved in that walk are RCU-safe.
That "actively participate in low-level path walking" includes things
like having its own ->d_hash()/->d_compare() routines, or by having
its own directory permission function that doesn't just use the common
helpers. Having a ->d_revalidate() function will also have this issue.
Note that instead of making everything RCU safe you can also choose to
abort the RCU pathwalk if your operation cannot be done safely under
RCU, but that obviously comes with a performance penalty. One common
pattern is to allow the simple cases under RCU, and abort only if you
need to do something more complicated.
So not everything needs to be RCU-safe, and things like the inode etc
that the VFS itself maintains obviously already are. But these fixes
tend to be about properly RCU-delaying things like ->s_fs_info that
are maintained by the filesystem and that got potentially released too
early. - Linus ]
* tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ext4_get_link(): fix breakage in RCU mode
cifs_get_link(): bail out in unsafe case
fuse: fix UAF in rcu pathwalks
procfs: make freeing proc_fs_info rcu-delayed
procfs: move dropping pde and pid from ->evict_inode() to ->free_inode()
nfs: fix UAF on pathwalk running into umount
nfs: make nfs_set_verifier() safe for use in RCU pathwalk
afs: fix __afs_break_callback() / afs_drop_open_mmap() race
hfsplus: switch to rcu-delayed unloading of nls and freeing ->s_fs_info
exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper
affs: free affs_sb_info with kfree_rcu()
rcu pathwalk: prevent bogus hard errors from may_lookup()
fs/super.c: don't drop ->s_user_ns until we free struct super_block itself
->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>
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>
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>
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Merge tag 'v6.8-rc-part2-smb-client' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client updates from Steve French:
"Various smb client fixes, including multichannel and for SMB3.1.1
POSIX extensions:
- debugging improvement (display start time for stats)
- two reparse point handling fixes
- various multichannel improvements and fixes
- SMB3.1.1 POSIX extensions open/create parsing fix
- retry (reconnect) improvement including new retrans mount parm, and
handling of two additional return codes that need to be retried on
- two minor cleanup patches and another to remove duplicate query
info code
- two documentation cleanup, and one reviewer email correction"
* tag 'v6.8-rc-part2-smb-client' of git://git.samba.org/sfrench/cifs-2.6:
cifs: update iface_last_update on each query-and-update
cifs: handle servers that still advertise multichannel after disabling
cifs: new mount option called retrans
cifs: reschedule periodic query for server interfaces
smb: client: don't clobber ->i_rdev from cached reparse points
smb: client: get rid of smb311_posix_query_path_info()
smb: client: parse owner/group when creating reparse points
smb: client: fix parsing of SMB3.1.1 POSIX create context
cifs: update known bugs mentioned in kernel docs for cifs
cifs: new nt status codes from MS-SMB2
cifs: pick channel for tcon and tdis
cifs: open_cached_dir should not rely on primary channel
smb3: minor documentation updates
Update MAINTAINERS email address
cifs: minor comment cleanup
smb3: show beginning time for per share stats
cifs: remove redundant variable tcon_exist
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Merge tag 'vfs-6.8.netfs' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull netfs updates from Christian Brauner:
"This extends the netfs helper library that network filesystems can use
to replace their own implementations. Both afs and 9p are ported. cifs
is ready as well but the patches are way bigger and will be routed
separately once this is merged. That will remove lots of code as well.
The overal goal is to get high-level I/O and knowledge of the page
cache and ouf of the filesystem drivers. This includes knowledge about
the existence of pages and folios
The pull request converts afs and 9p. This removes about 800 lines of
code from afs and 300 from 9p. For 9p it is now possible to do writes
in larger than a page chunks. Additionally, multipage folio support
can be turned on for 9p. Separate patches exist for cifs removing
another 2000+ lines. I've included detailed information in the
individual pulls I took.
Summary:
- Add NFS-style (and Ceph-style) locking around DIO vs buffered I/O
calls to prevent these from happening at the same time.
- Support for direct and unbuffered I/O.
- Support for write-through caching in the page cache.
- O_*SYNC and RWF_*SYNC writes use write-through rather than writing
to the page cache and then flushing afterwards.
- Support for write-streaming.
- Support for write grouping.
- Skip reads for which the server could only return zeros or EOF.
- The fscache module is now part of the netfs library and the
corresponding maintainer entry is updated.
- Some helpers from the fscache subsystem are renamed to mark them as
belonging to the netfs library.
- Follow-up fixes for the netfs library.
- Follow-up fixes for the 9p conversion"
* tag 'vfs-6.8.netfs' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (50 commits)
netfs: Fix wrong #ifdef hiding wait
cachefiles: Fix signed/unsigned mixup
netfs: Fix the loop that unmarks folios after writing to the cache
netfs: Fix interaction between write-streaming and cachefiles culling
netfs: Count DIO writes
netfs: Mark netfs_unbuffered_write_iter_locked() static
netfs: Fix proc/fs/fscache symlink to point to "netfs" not "../netfs"
netfs: Rearrange netfs_io_subrequest to put request pointer first
9p: Use length of data written to the server in preference to error
9p: Do a couple of cleanups
9p: Fix initialisation of netfs_inode for 9p
cachefiles: Fix __cachefiles_prepare_write()
9p: Use netfslib read/write_iter
afs: Use the netfs write helpers
netfs: Export the netfs_sreq tracepoint
netfs: Optimise away reads above the point at which there can be no data
netfs: Implement a write-through caching option
netfs: Provide a launder_folio implementation
netfs: Provide a writepages implementation
netfs, cachefiles: Pass upper bound length to allow expansion
...
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>
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Merge tag 'vfs-6.8.rw' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs rw updates from Christian Brauner:
"This contains updates from Amir for read-write backing file helpers
for stacking filesystems such as overlayfs:
- Fanotify is currently in the process of introducing pre content
events. Roughly, a new permission event will be added indicating
that it is safe to write to the file being accessed. These events
are used by hierarchical storage managers to e.g., fill the content
of files on first access.
During that work we noticed that our current permission checking is
inconsistent in rw_verify_area() and remap_verify_area().
Especially in the splice code permission checking is done multiple
times. For example, one time for the whole range and then again for
partial ranges inside the iterator.
In addition, we mostly do permission checking before we call
file_start_write() except for a few places where we call it after.
For pre-content events we need such permission checking to be done
before file_start_write(). So this is a nice reason to clean this
all up.
After this series, all permission checking is done before
file_start_write().
As part of this cleanup we also massaged the splice code a bit. We
got rid of a few helpers because we are alredy drowning in special
read-write helpers. We also cleaned up the return types for splice
helpers.
- Introduce generic read-write helpers for backing files. This lifts
some overlayfs code to common code so it can be used by the FUSE
passthrough work coming in over the next cycles. Make Amir and
Miklos the maintainers for this new subsystem of the vfs"
* tag 'vfs-6.8.rw' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (30 commits)
fs: fix __sb_write_started() kerneldoc formatting
fs: factor out backing_file_mmap() helper
fs: factor out backing_file_splice_{read,write}() helpers
fs: factor out backing_file_{read,write}_iter() helpers
fs: prepare for stackable filesystems backing file helpers
fsnotify: optionally pass access range in file permission hooks
fsnotify: assert that file_start_write() is not held in permission hooks
fsnotify: split fsnotify_perm() into two hooks
fs: use splice_copy_file_range() inline helper
splice: return type ssize_t from all helpers
fs: use do_splice_direct() for nfsd/ksmbd server-side-copy
fs: move file_start_write() into direct_splice_actor()
fs: fork splice_file_range() from do_splice_direct()
fs: create {sb,file}_write_not_started() helpers
fs: create file_write_started() helper
fs: create __sb_write_started() helper
fs: move kiocb_start_write() into vfs_iocb_iter_write()
fs: move permission hook out of do_iter_read()
fs: move permission hook out of do_iter_write()
fs: move file_start_write() into vfs_iter_write()
...
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
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
