Commit graph

52568 commits

Author SHA1 Message Date
Long Li
03bee01d62 CIFS: SMBD: Add SMB Direct protocol initial values and constants
To prepare for protocol implementation, add constants and user-configurable
values for the SMB Direct protocol.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:05 -06:00
Long Li
8339dd32fb CIFS: SMBD: Add rdma mount option
Add "rdma" to CIFS mount options to connect to SMB Direct.
Add checks to validate this is used on SMB 3.X dialects.

To connect to SMBDirect, use "mount.cifs -o rdma,vers=3.x".
At the time of this patch, 3.x can be 3.0, 3.02 or 3.1.1.

Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
2018-01-24 19:49:05 -06:00
Long Li
2b6ed88037 CIFS: SMBD: Introduce kernel config option CONFIG_CIFS_SMB_DIRECT
Build SMB Direct code when this option is set.

Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
2018-01-24 19:49:05 -06:00
Long Li
2dabfd5bab CIFS: SMBD: Add parameter rdata to smb2_new_read_req
This patch is for preparing upper layer for doing SMB read via RDMA write.

When we assemble the SMB read packet header, we need to know the I/O layout
if this request is to use a RDMA write. rdata has all the information we need
for memory registration. Add rdata to smb2_new_read_req.

Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
3cecf4865c cifs: avoid a kmalloc in smb2_send_recv/SendReceive2 for the common case
In both functions, use an array of 8 (arbitrary but should be big enough
for all current uses) iov and avoid having to kmalloc the array
for the common case.

If 8 is too small, then fall back to the original behaviour and use
kmalloc/kfree.

This should not change any behaviour but should save us a tiny amount of
cpu cycles.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
305428acf0 cifs: remove small_smb2_init
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
8eb7998e79 cifs: remove rfc1002 header from smb2_lease_ack
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
5dfe69a407 cifs: remove unused variable from SMB2_read
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
21ad9487ca cifs: remove rfc1002 header from smb2_oplock_break we get from server
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
b2fb7fecc9 cifs: remove rfc1002 header from smb2_query_info_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
7c00c3a625 cifs: remove rfc1002 header from smb2_query_directory_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
2fc803efe6 cifs: remove rfc1002 header from smb2_set_info_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:05 -06:00
Ronnie Sahlberg
f5688a6d7c cifs: remove rfc1002 header from smb2 read/write requests
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
ced93679cb cifs: remove rfc1002 header from smb2_lock_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
1f444e4c06 cifs: remove rfc1002 header from smb2_flush_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
4f33bc3587 cifs: remove rfc1002 header from smb2_create_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
88ea5cb7d4 cifs: remove rfc1002 header from smb2_sess_setup_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
661bb943a9 cifs: remove rfc1002 header from smb2_tree_connect_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
7f7ae759fb cifs: remove rfc1002 header from smb2_echo_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
9775468020 cifs: remove rfc1002 header from smb2_ioctl_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
afcccefdc3 cifs: remove rfc1002 header from smb2_close_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
4eecf4cfe1 cifs: remove rfc1002 header from smb2_tree_disconnect_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
45305eda6b cifs: remove rfc1002 header from smb2_logoff_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
13cacea7bb cifs: remove rfc1002 header from smb2_negotiate_req
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-01-24 19:49:04 -06:00
Ronnie Sahlberg
83b7739180 cifs: Add smb2_send_recv
This function is similar to SendReceive2 except it does not expect
a 4 byte rfc1002 length header in the first io vector.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-01-24 19:49:04 -06:00
Trond Myklebust
535cb8f319 lockd: Fix server refcounting
The server shouldn't actually delete the struct nlm_host until it hits
the garbage collector. In order to make that work correctly with the
refcount API, we can bump the refcount by one, and then use
refcount_dec_if_one() in the garbage collector.

Signed-off-by: Trond Myklebust <trondmy@gmail.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
2018-01-24 17:33:57 -05:00
Josef Bacik
e4fd493c05 Btrfs: fix stale entries in readdir
In fixing the readdir+pagefault deadlock I accidentally introduced a
stale entry regression in readdir.  If we get close to full for the
temporary buffer, and then skip a few delayed deletions, and then try to
add another entry that won't fit, we will emit the entries we found and
retry.  Unfortunately we delete entries from our del_list as we find
them, assuming we won't need them.  However our pos will be with
whatever our last entry was, which could be before the delayed deletions
we skipped, so the next search will add the deleted entries back into
our readdir buffer.  So instead don't delete entries we find in our
del_list so we can make sure we always find our delayed deletions.  This
is a slight perf hit for readdir with lots of pending deletions, but
hopefully this isn't a common occurrence.  If it is we can revist this
and optimize it.

cc: stable@vger.kernel.org
Fixes: 23b5ec7494 ("btrfs: fix readdir deadlock with pagefault")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-24 20:27:48 +01:00
Amir Goldstein
8383f17488 ovl: wire up NFS export operations
Now that NFS export operations are implemented, enable overlayfs NFS
export support if the "nfs_export" feature is enabled.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:06 +01:00
Amir Goldstein
0617015403 ovl: lookup indexed ancestor of lower dir
ovl_lookup_real() in lower layer walks back lower parents to find the
topmost indexed parent. If an indexed ancestor is found before reaching
lower layer root, ovl_lookup_real() is called recursively with upper
layer to walk back from indexed upper to the topmost connected/hashed
upper parent (or up to root).

ovl_lookup_real() in upper layer then walks forward to connect the topmost
upper overlay dir dentry and ovl_lookup_real() in lower layer continues to
walk forward to connect the decoded lower overlay dir dentry.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:05 +01:00
Amir Goldstein
4b91c30a5a ovl: lookup connected ancestor of dir in inode cache
Decoding a dir file handle requires walking backward up to layer root and
for lower dir also checking the index to see if any of the parents have
been copied up.

Lookup overlay ancestor dentry in inode/dentry cache by decoded real
parents to shortcut looking up all the way back to layer root.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:05 +01:00
Amir Goldstein
7a9dadef96 ovl: hash non-indexed dir by upper inode for NFS export
Non-indexed upper dirs are encoded as upper file handles. When NFS export
is enabled, hash non-indexed directory inodes by upper inode, so we can
find them in inode cache using the decoded upper inode.

When NFS export is disabled, directories are not indexed on copy up, so
hash non-indexed directory inodes by origin inode, the same hash key
that is used before copy up.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:04 +01:00
Amir Goldstein
988925164f ovl: decode pure lower dir file handles
Similar to decoding a pure upper dir file handle, decoding a pure lower
dir file handle is implemented by looking an overlay dentry of the same
path as the pure lower path and verifying that the overlay dentry's
real lower matches the decoded real lower file handle.

Unlike the case of upper dir file handle, the lookup of overlay path by
lower real path can fail or find a mismatched overlay dentry if any of
the lower parents have been copied up and renamed. To address this case
we will need to check if any of the lower parents are indexed.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:04 +01:00
Amir Goldstein
3b0bfc6ed3 ovl: decode indexed dir file handles
Decoding an indexed dir file handle is done by looking up the file handle
in index dir by name and then decoding the upper dir from the index origin
file handle. The decoded upper path is used to lookup an overlay dentry of
the same path.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:03 +01:00
Amir Goldstein
9436a1a339 ovl: decode lower file handles of unlinked but open files
Lookup overlay inode in cache by origin inode, so we can decode a file
handle of an open file even if the index has a whiteout index entry to
mark this overlay inode was unlinked.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:03 +01:00
Amir Goldstein
f71bd9cfb6 ovl: decode indexed non-dir file handles
Decoding an indexed non-dir file handle is similar to decoding a lower
non-dir file handle, but additionally, we lookup the file handle in index
dir by name to find the real upper inode.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:03 +01:00
Amir Goldstein
f941866fc4 ovl: decode lower non-dir file handles
Decoding a lower non-dir file handle is done by decoding the lower dentry
from underlying lower fs, finding or allocating an overlay inode that is
hashed by the real lower inode and instantiating an overlay dentry with
that inode.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:02 +01:00
Amir Goldstein
03e1c584ff ovl: encode lower file handles
For indexed or lower non-dir, encode a non-connectable lower file handle
from origin inode. For indexed or lower dir, when ofs->numlower == 1,
encode a lower file handle from lower dir.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:02 +01:00
Amir Goldstein
05e1f11816 ovl: copy up before encoding non-connectable dir file handle
Decoding a merge dir, whose origin's parent is under a redirected
lower dir is not always possible. As a simple aproximation, we do
not encode lower dir file handles when overlay has multiple lower
layers and origin is below the topmost lower layer.

We should later relax this condition and copy up only the parent
that is under a redirected lower.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:01 +01:00
Amir Goldstein
b305e8443f ovl: encode non-indexed upper file handles
We only need to encode origin if there is a chance that the same object was
encoded pre copy up and then we need to stay consistent with the same
encoding also after copy up.

In case a non-pure upper is not indexed, then it was copied up before NFS
export support was enabled. In that case, we don't need to worry about
staying consistent with pre copy up encoding and we encode an upper file
handle.

This mitigates the problem that with no index, we cannot find an upper
inode from origin inode, so we cannot decode a non-indexed upper from
origin file handle.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:01 +01:00
Amir Goldstein
3985b70a3e ovl: decode connected upper dir file handles
Until this change, we decoded upper file handles by instantiating an
overlay dentry from the real upper dentry. This is sufficient to handle
pure upper files, but insufficient to handle merge/impure dirs.

To that end, if decoded real upper dir is connected and hashed, we
lookup an overlay dentry with the same path as the real upper dir.
If decoded real upper is non-dir, we instantiate a disconnected overlay
dentry as before this change.

Because ovl_fh_to_dentry() returns a connected overlay dir dentry,
exportfs never needs to call get_parent() and get_name() to reconnect an
upper overlay dir. Because connectable non-dir file handles are not
supported, exportfs will not be able to use fh_to_parent() and get_name()
methods to reconnect a disconnected non-dir to its parent. Therefore, the
methods get_parent() and get_name() are implemented just to print out a
sanity warning and the method fh_to_parent() is implemented to warn the
user that using the 'subtree_check' exportfs option is not supported.

An alternative approach could have been to implement instantiating of
an overlay directory inode from origin/index and implement get_parent()
and get_name() by calling into underlying fs operations and them
instantiating the overlay parent dir.

The reasons for not choosing the get_parent() approach were:
- Obtaining a disconnected overlay dir dentry would requires a
  delicate re-factoring of ovl_lookup() to get a dentry with overlay
  parent info. It was preferred to avoid doing that re-factoring unless
  it was proven worthy.
- Going down the path of disconnected dir would mean that the (non
  trivial) code path of d_splice_alias() could be traveled and that
  meant writing more tests and introduces race cases that are very hard
  to hit on purpose. Taking the path of connecting overlay dentry by
  forward lookup is therefore the safe and boring way to avoid surprises.

The culprits of the chosen "connected overlay dentry" approach:
- We need to take special care to rename of ancestors while connecting
  the overlay dentry by real dentry path. These subtleties are usually
  handled by generic exportfs and VFS code.
- In a hypothetical workload, we could end up in a loop trying to connect,
  interrupted by rename and restarting connect forever.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:00 +01:00
Amir Goldstein
8556a4205b ovl: decode pure upper file handles
Decoding an upper file handle is done by decoding the upper dentry from
underlying upper fs, finding or allocating an overlay inode that is
hashed by the real upper inode and instantiating an overlay dentry with
that inode.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:26:00 +01:00
Amir Goldstein
8ed5eec9d6 ovl: encode pure upper file handles
Encode overlay file handles as struct ovl_fh containing the file handle
encoding of the real upper inode.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:59 +01:00
Miklos Szeredi
f9c34674bc vfs: factor out helpers d_instantiate_anon() and d_alloc_anon()
Those helpers are going to be used by overlayfs to implement
NFS export decode.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:59 +01:00
Amir Goldstein
c62520a83b ovl: store 'has_upper' and 'opaque' as bit flags
We need to make some room in struct ovl_entry to store information
about redirected ancestors for NFS export, so cram two booleans as
bit flags.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:58 +01:00
Amir Goldstein
aa3ff3c152 ovl: copy up of disconnected dentries
With NFS export, some operations on decoded file handles (e.g. open,
link, setattr, xattr_set) may call copy up with a disconnected non-dir.
In this case, we will copy up lower inode to index dir without
linking it to upper dir.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:58 +01:00
Amir Goldstein
829c28be9b ovl: use d_splice_alias() in place of d_add() in lookup
This is required for NFS export.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:57 +01:00
Amir Goldstein
0aceb53e73 ovl: do not pass overlay dentry to ovl_get_inode()
This is needed for using ovl_get_inode() for decoding file handles
for NFS export.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:57 +01:00
Amir Goldstein
91ffe7beb3 ovl: factor out ovl_get_index_fh() helper
The helper is needed to lookup an index by file handle for NFS export.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:56 +01:00
Amir Goldstein
24f0b17203 ovl: whiteout orphan index entries on mount
Orphan index entries are non-dir index entries whose union nlink count
dropped to zero. With index=on, orphan index entries are removed on
mount. With NFS export feature enabled, orphan index entries are replaced
with white out index entries to block future open by handle from opening
the lower file.

When dir index has a stale 'upper' xattr, we assume that the upper dir
was removed and we treat the dir index as orphan entry that needs to be
whited out or removed.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:56 +01:00
Amir Goldstein
e7dd0e7134 ovl: whiteout index when union nlink drops to zero
With NFS export feature enabled, when overlay inode nlink drops to
zero, instead of removing the index entry, replace it with a whiteout
index entry.

This is needed for NFS export in order to prevent future open by handle
from opening the lower file directly.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-01-24 11:25:56 +01:00