Commit Graph

801 Commits

Author SHA1 Message Date
Christian Brauner
39a6497a9b
9p: use stub posix acl handlers
Now that 9p supports the get and set acl inode operations and the vfs
has been switched to the new posi api, 9p can simply rely on the stub
posix acl handlers. The custom xattr handlers and associated unused
helpers can be removed.

Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:32 +02:00
Christian Brauner
079da62938
9p: implement set acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

In order to build a type safe posix api around get and set acl we need
all filesystem to implement get and set acl.

So far 9p implemented a ->get_inode_acl() operation that didn't require
access to the dentry in order to allow (limited) permission checking via
posix acls in the vfs. Now that we have get and set acl inode operations
that take a dentry argument we can give 9p get and set acl inode
operations.

This is mostly a light refactoring of the codepaths currently used in 9p
posix acl xattr handler. After we have fully implemented the posix acl
api and switched the vfs over to it, the 9p specific posix acl xattr
handler and associated code will be removed.

Note, until the vfs has been switched to the new posix acl api this
patch is a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:28 +02:00
Christian Brauner
6cd4d4e8b6
9p: implement get acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

In order to build a type safe posix api around get and set acl we need
all filesystem to implement get and set acl.

So far 9p implemented a ->get_inode_acl() operation that didn't require
access to the dentry in order to allow (limited) permission checking via
posix acls in the vfs. Now that we have get and set acl inode operations
that take a dentry argument we can give 9p get and set acl inode
operations.

This is mostly a refactoring of the codepaths currently used in 9p posix
acl xattr handler. After we have fully implemented the posix acl api and
switched the vfs over to it, the 9p specific posix acl xattr handler and
associated code will be removed.

Note, until the vfs has been switched to the new posix acl api this
patch is a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:28 +02:00
Christian Brauner
cac2f8b8d8
fs: rename current get acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

The current inode operation for getting posix acls takes an inode
argument but various filesystems (e.g., 9p, cifs, overlayfs) need access
to the dentry. In contrast to the ->set_acl() inode operation we cannot
simply extend ->get_acl() to take a dentry argument. The ->get_acl()
inode operation is called from:

acl_permission_check()
-> check_acl()
   -> get_acl()

which is part of generic_permission() which in turn is part of
inode_permission(). Both generic_permission() and inode_permission() are
called in the ->permission() handler of various filesystems (e.g.,
overlayfs). So simply passing a dentry argument to ->get_acl() would
amount to also having to pass a dentry argument to ->permission(). We
should avoid this unnecessary change.

So instead of extending the existing inode operation rename it from
->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that
passes a dentry argument and which filesystems that need access to the
dentry can implement instead of ->get_inode_acl(). Filesystems like cifs
which allow setting and getting posix acls but not using them for
permission checking during lookup can simply not implement
->get_inode_acl().

This is intended to be a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:27 +02:00
Yang Li
e3baced02a 9p: Fix some kernel-doc comments
Remove warnings found by running scripts/kernel-doc,
which is caused by using 'make W=1'.
fs/9p/fid.c:35: warning: Function parameter or member 'pfid' not described in 'v9fs_fid_add'
fs/9p/fid.c:35: warning: Excess function parameter 'fid' description in 'v9fs_fid_add'
fs/9p/fid.c:80: warning: Function parameter or member 'pfid' not described in 'v9fs_open_fid_add'
fs/9p/fid.c:80: warning: Excess function parameter 'fid' description in 'v9fs_open_fid_add'

Link: https://lkml.kernel.org/r/20220615012039.43479-1-yang.lee@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
[Dominique: further adjust comment]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Dominique Martinet
dafbe68973 9p fid refcount: cleanup p9_fid_put calls
Simplify p9_fid_put cleanup path in many 9p functions since the function
is noop on null or error fids.

Also make the *_add_fid() helpers "steal" the fid by nulling its
pointer, so put after them will be noop.

This should lead to no change of behaviour

Link: https://lkml.kernel.org/r/20220612085330.1451496-7-asmadeus@codewreck.org
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Dominique Martinet
b48dbb998d 9p fid refcount: add p9_fid_get/put wrappers
I was recently reminded that it is not clear that p9_client_clunk()
was actually just decrementing refcount and clunking only when that
reaches zero: make it clear through a set of helpers.

This will also allow instrumenting refcounting better for debugging
next patch

Link: https://lkml.kernel.org/r/20220612085330.1451496-5-asmadeus@codewreck.org
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Tyler Hicks
b296d05746 9p: Fix minor typo in code comment
Fix s/patch/path/ typo and make it clear that we're talking about
multiple path components.

Link: https://lkml.kernel.org/r/20220527000003.355812-6-tyhicks@linux.microsoft.com
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Tyler Hicks
47b1e3432b 9p: Remove unnecessary variable for old fids while walking from d_parent
Remove the ofid variable that's local to the conditional block in favor
of the old_fid variable that's local to the entire function.

Link: https://lkml.kernel.org/r/20220527000003.355812-5-tyhicks@linux.microsoft.com
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Tyler Hicks
c58c72d301 9p: Make the path walk logic more clear about when cloning is required
Cloning during a path component walk is only needed when the old fid
used for the walk operation is the root fid. Make that clear by
comparing the two fids rather than using an additional variable.

Link: https://lkml.kernel.org/r/20220527000003.355812-4-tyhicks@linux.microsoft.com
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Tyler Hicks
cba83f47fc 9p: Track the root fid with its own variable during lookups
Improve readability by using a new variable when dealing with the root
fid. The root fid requires special handling in comparison to other fids
used during fid lookup.

Link: https://lkml.kernel.org/r/20220527000003.355812-3-tyhicks@linux.microsoft.com
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-07-02 18:52:21 +09:00
Dominique Martinet
b0017602fd 9p: fix EBADF errors in cached mode
cached operations sometimes need to do invalid operations (e.g. read
on a write only file)
Historic fscache had added a "writeback fid", a special handle opened
RW as root, for this. The conversion to new fscache missed that bit.

This commit reinstates a slightly lesser variant of the original code
that uses the writeback fid for partial pages backfills if the regular
user fid had been open as WRONLY, and thus would lack read permissions.

Link: https://lkml.kernel.org/r/20220614033802.1606738-1-asmadeus@codewreck.org
Fixes: eb497943fa ("9p: Convert to using the netfs helper lib to do reads and caching")
Cc: stable@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Reported-By: Christian Schoenebeck <linux_oss@crudebyte.com>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Tested-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-06-17 06:03:30 +09:00
Tyler Hicks
2a3dcbccd6 9p: Fix refcounting during full path walks for fid lookups
Decrement the refcount of the parent dentry's fid after walking
each path component during a full path walk for a lookup. Failure to do
so can lead to fids that are not clunked until the filesystem is
unmounted, as indicated by this warning:

 9pnet: found fid 3 not clunked

The improper refcounting after walking resulted in open(2) returning
-EIO on any directories underneath the mount point when using the virtio
transport. When using the fd transport, there's no apparent issue until
the filesytem is unmounted and the warning above is emitted to the logs.

In some cases, the user may not yet be attached to the filesystem and a
new root fid, associated with the user, is created and attached to the
root dentry before the full path walk is performed. Increment the new
root fid's refcount to two in that situation so that it can be safely
decremented to one after it is used for the walk operation. The new fid
will still be attached to the root dentry when
v9fs_fid_lookup_with_uid() returns so a final refcount of one is
correct/expected.

Link: https://lkml.kernel.org/r/20220527000003.355812-2-tyhicks@linux.microsoft.com
Link: https://lkml.kernel.org/r/20220612085330.1451496-4-asmadeus@codewreck.org
Fixes: 6636b6dcc3 ("9p: add refcount to p9_fid struct")
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
[Dominique: fix clunking fid multiple times discussed in second link]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-06-15 12:05:33 +09:00
Dominique Martinet
e5690f2632 9p: fix fid refcount leak in v9fs_vfs_get_link
we check for protocol version later than required, after a fid has
been obtained. Just move the version check earlier.

Link: https://lkml.kernel.org/r/20220612085330.1451496-3-asmadeus@codewreck.org
Fixes: 6636b6dcc3 ("9p: add refcount to p9_fid struct")
Cc: stable@vger.kernel.org
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-06-15 12:05:29 +09:00
Dominique Martinet
beca774fc5 9p: fix fid refcount leak in v9fs_vfs_atomic_open_dotl
We need to release directory fid if we fail halfway through open

This fixes fid leaking with xfstests generic 531

Link: https://lkml.kernel.org/r/20220612085330.1451496-2-asmadeus@codewreck.org
Fixes: 6636b6dcc3 ("9p: add refcount to p9_fid struct")
Cc: stable@vger.kernel.org
Reported-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-06-15 12:05:21 +09:00
David Howells
40a8110120 netfs: Rename the netfs_io_request cleanup op and give it an op pointer
The netfs_io_request cleanup op is now always in a position to be given a
pointer to a netfs_io_request struct, so this can be passed in instead of
the mapping and private data arguments (both of which are included in the
struct).

So rename the ->cleanup op to ->free_request (to match ->init_request) and
pass in the I/O pointer.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
2022-06-10 20:55:21 +01:00
Linus Torvalds
e81fb4198e netfs: Further cleanups after struct netfs_inode wrapper introduced
Change the signature of netfs helper functions to take a struct netfs_inode
pointer rather than a struct inode pointer where appropriate, thereby
relieving the need for the network filesystem to convert its internal inode
format down to the VFS inode only for netfslib to bounce it back up.  For
type safety, it's better not to do that (and it's less typing too).

Give netfs_write_begin() an extra argument to pass in a pointer to the
netfs_inode struct rather than deriving it internally from the file
pointer.  Note that the ->write_begin() and ->write_end() ops are intended
to be replaced in the future by netfslib code that manages this without the
need to call in twice for each page.

netfs_readpage() and similar are intended to be pointed at directly by the
address_space_operations table, so must stick to the signature dictated by
the function pointers there.

Changes
=======
- Updated the kerneldoc comments and documentation [DH].

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/CAHk-=wgkwKyNmNdKpQkqZ6DnmUL-x9hp0YBnUGjaPFEAdxDTbw@mail.gmail.com/
2022-06-10 20:55:21 +01:00
David Howells
874c8ca1e6 netfs: Fix gcc-12 warning by embedding vfs inode in netfs_i_context
While randstruct was satisfied with using an open-coded "void *" offset
cast for the netfs_i_context <-> inode casting, __builtin_object_size() as
used by FORTIFY_SOURCE was not as easily fooled.  This was causing the
following complaint[1] from gcc v12:

  In file included from include/linux/string.h:253,
                   from include/linux/ceph/ceph_debug.h:7,
                   from fs/ceph/inode.c:2:
  In function 'fortify_memset_chk',
      inlined from 'netfs_i_context_init' at include/linux/netfs.h:326:2,
      inlined from 'ceph_alloc_inode' at fs/ceph/inode.c:463:2:
  include/linux/fortify-string.h:242:25: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
    242 |                         __write_overflow_field(p_size_field, size);
        |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fix this by embedding a struct inode into struct netfs_i_context (which
should perhaps be renamed to struct netfs_inode).  The struct inode
vfs_inode fields are then removed from the 9p, afs, ceph and cifs inode
structs and vfs_inode is then simply changed to "netfs.inode" in those
filesystems.

Further, rename netfs_i_context to netfs_inode, get rid of the
netfs_inode() function that converted a netfs_i_context pointer to an
inode pointer (that can now be done with &ctx->inode) and rename the
netfs_i_context() function to netfs_inode() (which is now a wrapper
around container_of()).

Most of the changes were done with:

  perl -p -i -e 's/vfs_inode/netfs.inode/'g \
        `git grep -l 'vfs_inode' -- fs/{9p,afs,ceph,cifs}/*.[ch]`

Kees suggested doing it with a pair structure[2] and a special
declarator to insert that into the network filesystem's inode
wrapper[3], but I think it's cleaner to embed it - and then it doesn't
matter if struct randomisation reorders things.

Dave Chinner suggested using a filesystem-specific VFS_I() function in
each filesystem to convert that filesystem's own inode wrapper struct
into the VFS inode struct[4].

Version #2:
 - Fix a couple of missed name changes due to a disabled cifs option.
 - Rename nfs_i_context to nfs_inode
 - Use "netfs" instead of "nic" as the member name in per-fs inode wrapper
   structs.

[ This also undoes commit 507160f46c ("netfs: gcc-12: temporarily
  disable '-Wattribute-warning' for now") that is no longer needed ]

Fixes: bc899ee1c8 ("netfs: Add a netfs inode context")
Reported-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
cc: Jonathan Corbet <corbet@lwn.net>
cc: Eric Van Hensbergen <ericvh@gmail.com>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Christian Schoenebeck <linux_oss@crudebyte.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Ilya Dryomov <idryomov@gmail.com>
cc: Steve French <smfrench@gmail.com>
cc: William Kucharski <william.kucharski@oracle.com>
cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
cc: Dave Chinner <david@fromorbit.com>
cc: linux-doc@vger.kernel.org
cc: v9fs-developer@lists.sourceforge.net
cc: linux-afs@lists.infradead.org
cc: ceph-devel@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: samba-technical@lists.samba.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-hardening@vger.kernel.org
Link: https://lore.kernel.org/r/d2ad3a3d7bdd794c6efb562d2f2b655fb67756b9.camel@kernel.org/ [1]
Link: https://lore.kernel.org/r/20220517210230.864239-1-keescook@chromium.org/ [2]
Link: https://lore.kernel.org/r/20220518202212.2322058-1-keescook@chromium.org/ [3]
Link: https://lore.kernel.org/r/20220524101205.GI2306852@dread.disaster.area/ [4]
Link: https://lore.kernel.org/r/165296786831.3591209.12111293034669289733.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/165305805651.4094995.7763502506786714216.stgit@warthog.procyon.org.uk # v2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-06-09 13:55:00 -07:00
Matthew Wilcox (Oracle)
a26d3411bb 9p: Convert to release_folio
A straightforward conversion as it already works in terms of folios.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-09 23:12:32 -04:00
Matthew Wilcox (Oracle)
6c62371b7f fs: Convert netfs_readpage to netfs_read_folio
This is straightforward because netfs already worked in terms of folios.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-05-09 16:21:44 -04:00
Matthew Wilcox (Oracle)
9d6b0cd757 fs: Remove flags parameter from aops->write_begin
There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-05-08 14:28:19 -04:00
Matthew Wilcox (Oracle)
de2a931150 fs: Remove aop_flags parameter from netfs_write_begin()
There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-05-08 14:28:19 -04:00
Linus Torvalds
f008b1d6e1 Netfs prep for write helpers
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAmI1HOwACgkQ+7dXa6fL
 C2u9mA/+LUdXHqlvET/PAtFTg75bUPeOFGLnuDnYl1Ng2FCKMSodAohpbVtENxsK
 E/gTVS7uiVZFQgC+YmNA00z6eIQkAaDVyvKyEcUbKREBbUgONfJ/HLeaK/NvVKxx
 TY5gx/POdG6yHRQXL6JGBqSJUB8bZrGKwnJm8ebzeKOji9n7GSJBYiMlYBA7EAhs
 Aut/P7Y39ISHLw3y+y5czBeRoubljmTyznbP20xUZEzrRwhTpNwpJVzBGUZU635T
 93Sqcp//0U5LIdn6Pg6DUGHBMBTNDNJChb21ZoBusF/HHswXsOOnf/mcRUBSJUTI
 M1WSpNLk8PRBgajMdIymQpGU1sCZZzJ3krrSA3RcXdN6GPHwZg8kKjoroHsLDL6l
 igPbDSMJ5wfiwA2A2gXbY1CkAl3ik5ccb7ZqhTwS0WBk0vOnHmAsE9cs/bBo7Xii
 GTiWXEFOgtJiXANPMS2P9DiOS3ZQNf+wxotCYdkGPOXuX9wnIo1Kmy8XfujQ1bXf
 pJsEZKfeyROKrzyKWgqLI64/Kg5xNueoFQZfDpOlZYzF1uDstynADPUt0eQD706q
 jcuKaXLN3rn5gSPun5mWOYbRtXVgOLdFL/7zptMVJwFKBFguQENhjG4UMNZcjkVA
 3Mr0kGocsgoCSk1oDBkFlrw1wIsXxWbkRBL1Pww6kovivuGUwoo=
 =j0yx
 -----END PGP SIGNATURE-----

Merge tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull netfs updates from David Howells:
 "Netfs prep for write helpers.

  Having had a go at implementing write helpers and content encryption
  support in netfslib, it seems that the netfs_read_{,sub}request
  structs and the equivalent write request structs were almost the same
  and so should be merged, thereby requiring only one set of
  alloc/get/put functions and a common set of tracepoints.

  Merging the structs also has the advantage that if a bounce buffer is
  added to the request struct, a read operation can be performed to fill
  the bounce buffer, the contents of the buffer can be modified and then
  a write operation can be performed on it to send the data wherever it
  needs to go using the same request structure all the way through. The
  I/O handlers would then transparently perform any required crypto.
  This should make it easier to perform RMW cycles if needed.

  The potentially common functions and structs, however, by their names
  all proclaim themselves to be associated with the read side of things.

  The bulk of these changes alter this in the following ways:

   - Rename struct netfs_read_{,sub}request to netfs_io_{,sub}request.

   - Rename some enums, members and flags to make them more appropriate.

   - Adjust some comments to match.

   - Drop "read"/"rreq" from the names of common functions. For
     instance, netfs_get_read_request() becomes netfs_get_request().

   - The ->init_rreq() and ->issue_op() methods become ->init_request()
     and ->issue_read(). I've kept the latter as a read-specific
     function and in another branch added an ->issue_write() method.

  The driver source is then reorganised into a number of files:

        fs/netfs/buffered_read.c        Create read reqs to the pagecache
        fs/netfs/io.c                   Dispatchers for read and write reqs
        fs/netfs/main.c                 Some general miscellaneous bits
        fs/netfs/objects.c              Alloc, get and put functions
        fs/netfs/stats.c                Optional procfs statistics.

  and future development can be fitted into this scheme, e.g.:

        fs/netfs/buffered_write.c       Modify the pagecache
        fs/netfs/buffered_flush.c       Writeback from the pagecache
        fs/netfs/direct_read.c          DIO read support
        fs/netfs/direct_write.c         DIO write support
        fs/netfs/unbuffered_write.c     Write modifications directly back

  Beyond the above changes, there are also some changes that affect how
  things work:

   - Make fscache_end_operation() generally available.

   - In the netfs tracing header, generate enums from the symbol ->
     string mapping tables rather than manually coding them.

   - Add a struct for filesystems that uses netfslib to put into their
     inode wrapper structs to hold extra state that netfslib is
     interested in, such as the fscache cookie. This allows netfslib
     functions to be set in filesystem operation tables and jumped to
     directly without having to have a filesystem wrapper.

   - Add a member to the struct added above to track the remote inode
     length as that may differ if local modifications are buffered. We
     may need to supply an appropriate EOF pointer when storing data (in
     AFS for example).

   - Pass extra information to netfs_alloc_request() so that the
     ->init_request() hook can access it and retain information to
     indicate the origin of the operation.

   - Make the ->init_request() hook return an error, thereby allowing a
     filesystem that isn't allowed to cache an inode (ceph or cifs, for
     example) to skip readahead.

   - Switch to using refcount_t for subrequests and add tracepoints to
     log refcount changes for the request and subrequest structs.

   - Add a function to consolidate dispatching a read request. Similar
     code is used in three places and another couple are likely to be
     added in the future"

Link: https://lore.kernel.org/all/2639515.1648483225@warthog.procyon.org.uk/

* tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Maintain netfs_i_context::remote_i_size
  netfs: Keep track of the actual remote file size
  netfs: Split some core bits out into their own file
  netfs: Split fs/netfs/read_helper.c
  netfs: Rename read_helper.c to io.c
  netfs: Prepare to split read_helper.c
  netfs: Add a function to consolidate beginning a read
  netfs: Add a netfs inode context
  ceph: Make ceph_init_request() check caps on readahead
  netfs: Change ->init_request() to return an error code
  netfs: Refactor arguments for netfs_alloc_read_request
  netfs: Adjust the netfs_failure tracepoint to indicate non-subreq lines
  netfs: Trace refcounting on the netfs_io_subrequest struct
  netfs: Trace refcounting on the netfs_io_request struct
  netfs: Adjust the netfs_rreq tracepoint slightly
  netfs: Split netfs_io_* object handling out
  netfs: Finish off rename of netfs_read_request to netfs_io_request
  netfs: Rename netfs_read_*request to netfs_io_*request
  netfs: Generate enums from trace symbol mapping lists
  fscache: export fscache_end_operation()
2022-03-31 15:49:36 -07:00
Linus Torvalds
6b1f86f8e9 Filesystem folio changes for 5.18
Primarily this series converts some of the address_space operations
 to take a folio instead of a page.
 
 ->is_partially_uptodate() takes a folio instead of a page and changes the
 type of the 'from' and 'count' arguments to make it obvious they're bytes.
 ->invalidatepage() becomes ->invalidate_folio() and has a similar type change.
 ->launder_page() becomes ->launder_folio()
 ->set_page_dirty() becomes ->dirty_folio() and adds the address_space as
 an argument.
 
 There are a couple of other misc changes up front that weren't worth
 separating into their own pull request.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEejHryeLBw/spnjHrDpNsjXcpgj4FAmI4hqMACgkQDpNsjXcp
 gj7r7Af/fVJ7m8kKqjP/IayX3HiJRuIDQw+vM++BlRNXdjz+IyED6whdmFGxJeOY
 BMyT+8ApOAz7ErS4G+7fAv4ScJK/aEgFUsnSeAiCp0PliiEJ5NNJzElp6sVmQ7H5
 SX7+Ek444FZUGsQuy0qL7/ELpR3ditnD7x+5U2g0p5TeaHGUQn84crRyfR4xuhNG
 EBD9D71BOb7OxUcOHe93pTkK51QsQ0aCrcIsB1tkK5KR0BAthn1HqF7ehL90Rvrr
 omx5M7aDWGY4oj7IKrhlAs+55Ah2WaOzrZBp0FXNbr4UENDBKWKyUxErwa4xPkf6
 Gm1iQG/CspOHnxN3YWsd5WjtlL3A+A==
 =cOiq
 -----END PGP SIGNATURE-----

Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache

Pull filesystem folio updates from Matthew Wilcox:
 "Primarily this series converts some of the address_space operations to
  take a folio instead of a page.

  Notably:

   - a_ops->is_partially_uptodate() takes a folio instead of a page and
     changes the type of the 'from' and 'count' arguments to make it
     obvious they're bytes.

   - a_ops->invalidatepage() becomes ->invalidate_folio() and has a
     similar type change.

   - a_ops->launder_page() becomes ->launder_folio()

   - a_ops->set_page_dirty() becomes ->dirty_folio() and adds the
     address_space as an argument.

  There are a couple of other misc changes up front that weren't worth
  separating into their own pull request"

* tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits)
  fs: Remove aops ->set_page_dirty
  fb_defio: Use noop_dirty_folio()
  fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio
  fs: Convert __set_page_dirty_buffers to block_dirty_folio
  nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio()
  mm: Convert swap_set_page_dirty() to swap_dirty_folio()
  ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio
  f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio
  f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio
  f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio
  afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio()
  btrfs: Convert extent_range_redirty_for_io() to use folios
  fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
  btrfs: Convert from set_page_dirty to dirty_folio
  fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
  fs: Add aops->dirty_folio
  fs: Remove aops->launder_page
  orangefs: Convert launder_page to launder_folio
  nfs: Convert from launder_page to launder_folio
  fuse: Convert from launder_page to launder_folio
  ...
2022-03-22 18:26:56 -07:00
Muchun Song
fd60b28842 fs: allocate inode by using alloc_inode_sb()
The inode allocation is supposed to use alloc_inode_sb(), so convert
kmem_cache_alloc() of all filesystems to alloc_inode_sb().

Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>		[ext4]
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Alex Shi <alexs@kernel.org>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Fam Zheng <fam.zheng@bytedance.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kari Argillander <kari.argillander@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:03 -07:00
David Howells
bc899ee1c8 netfs: Add a netfs inode context
Add a netfs_i_context struct that should be included in the network
filesystem's own inode struct wrapper, directly after the VFS's inode
struct, e.g.:

	struct my_inode {
		struct {
			/* These must be contiguous */
			struct inode		vfs_inode;
			struct netfs_i_context	netfs_ctx;
		};
	};

The netfs_i_context struct so far contains a single field for the network
filesystem to use - the cache cookie:

	struct netfs_i_context {
		...
		struct fscache_cookie	*cache;
	};

Three functions are provided to help with this:

 (1) void netfs_i_context_init(struct inode *inode,
			       const struct netfs_request_ops *ops);

     Initialise the netfs context and set the operations.

 (2) struct netfs_i_context *netfs_i_context(struct inode *inode);

     Find the netfs context from the VFS inode.

 (3) struct inode *netfs_inode(struct netfs_i_context *ctx);

     Find the VFS inode from the netfs context.

Changes
=======
ver #4)
 - Fix netfs_is_cache_enabled() to check cookie->cache_priv to see if a
   cache is present[3].
 - Fix netfs_skip_folio_read() to zero out all of the page, not just some
   of it[3].

ver #3)
 - Split out the bit to move ceph cap-getting on readahead into
   ceph_init_request()[1].
 - Stick in a comment to the netfs inode structs indicating the contiguity
   requirements[2].

ver #2)
 - Adjust documentation to match.
 - Use "#if IS_ENABLED()" in netfs_i_cookie(), not "#ifdef".
 - Move the cap check from ceph_readahead() to ceph_init_request() to be
   called from netfslib.
 - Remove ceph_readahead() and use  netfs_readahead() directly instead.

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

Link: https://lore.kernel.org/r/8af0d47f17d89c06bbf602496dd845f2b0bf25b3.camel@kernel.org/ [1]
Link: https://lore.kernel.org/r/beaf4f6a6c2575ed489adb14b257253c868f9a5c.camel@kernel.org/ [2]
Link: https://lore.kernel.org/r/3536452.1647421585@warthog.procyon.org.uk/ [3]
Link: https://lore.kernel.org/r/164622984545.3564931.15691742939278418580.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/164678213320.1200972.16807551936267647470.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/164692909854.2099075.9535537286264248057.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/306388.1647595110@warthog.procyon.org.uk/ # v4
2022-03-18 09:29:05 +00:00
David Howells
2de1604173 netfs: Change ->init_request() to return an error code
Change the request initialisation function to return an error code so that
the network filesystem can return a failure (ENOMEM, for example).

This will also allow ceph to abort a ->readahead() op if the server refuses
to give it a cap allowing local caching from within the netfslib framework
(errors aren't passed back through ->readahead(), so returning, say,
-ENOBUFS will cause the op to be aborted).

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

Link: https://lore.kernel.org/r/164678212401.1200972.16537041523832944934.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/164692905398.2099075.5238033621684646524.stgit@warthog.procyon.org.uk/ # v3
2022-03-18 09:24:00 +00:00
David Howells
f18a378580 netfs: Finish off rename of netfs_read_request to netfs_io_request
Adjust helper function names and comments after mass rename of
struct netfs_read_*request to struct netfs_io_*request.

Changes
=======
ver #2)
 - Make the changes in the docs also.

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

Link: https://lore.kernel.org/r/164622992433.3564931.6684311087845150271.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/164678196111.1200972.5001114956865989528.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/164692892567.2099075.13895804222087028813.stgit@warthog.procyon.org.uk/ # v3
2022-03-18 09:24:00 +00:00
David Howells
6a19114b8e netfs: Rename netfs_read_*request to netfs_io_*request
Rename netfs_read_*request to netfs_io_*request so that the same structures
can be used for the write helpers too.

perl -p -i -e 's/netfs_read_(request|subrequest)/netfs_io_$1/g' \
   `git grep -l 'netfs_read_\(sub\|\)request'`
perl -p -i -e 's/nr_rd_ops/nr_outstanding/g' \
   `git grep -l nr_rd_ops`
perl -p -i -e 's/nr_wr_ops/nr_copy_ops/g' \
   `git grep -l nr_wr_ops`
perl -p -i -e 's/netfs_read_source/netfs_io_source/g' \
   `git grep -l 'netfs_read_source'`
perl -p -i -e 's/netfs_io_request_ops/netfs_request_ops/g' \
   `git grep -l 'netfs_io_request_ops'`
perl -p -i -e 's/init_rreq/init_request/g' \
   `git grep -l 'init_rreq'`

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

Link: https://lore.kernel.org/r/164622988070.3564931.7089670190434315183.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/164678195157.1200972.366609966927368090.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/164692891535.2099075.18435198075367420588.stgit@warthog.procyon.org.uk/ # v3
2022-03-18 09:24:00 +00:00
Matthew Wilcox (Oracle)
8fb72b4a76 fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
Convert all users of fscache_set_page_dirty to use fscache_dirty_folio.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15 08:34:36 -04:00
Matthew Wilcox (Oracle)
76dba92720 9p: Convert from launder_page to launder_folio
Trivial conversion.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15 08:23:30 -04:00
Matthew Wilcox (Oracle)
040cdd4bf9 9p: Convert to invalidate_folio
This is a trivial conversion.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15 08:23:29 -04:00
Dominique Martinet
22e424feb6 Revert "fs/9p: search open fids first"
This reverts commit 478ba09edc.

That commit was meant as a fix for setattrs with by fd (e.g. ftruncate)
to use an open fid instead of the first fid it found on lookup.
The proper fix for that is to use the fid associated with the open file
struct, available in iattr->ia_file for such operations, and was
actually done just before in 6624664160 ("9p: retrieve fid from file
when file instance exist.")
As such, this commit is no longer required.

Furthermore, changing lookup to return open fids first had unwanted side
effects, as it turns out the protocol forbids the use of open fids for
further walks (e.g. clone_fid) and we broke mounts for some servers
enforcing this rule.

Note this only reverts to the old working behaviour, but it's still
possible for lookup to return open fids if dentry->d_fsdata is not set,
so more work is needed to make sure we respect this rule in the future,
for example by adding a flag to the lookup functions to only match
certain fid open modes depending on caller requirements.

Link: https://lkml.kernel.org/r/20220130130651.712293-1-asmadeus@codewreck.org
Fixes: 478ba09edc ("fs/9p: search open fids first")
Cc: stable@vger.kernel.org # v5.11+
Reported-by: ron minnich <rminnich@gmail.com>
Reported-by: ng@0x80.stream
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-01-30 22:13:37 +09:00
Linus Torvalds
49ad227d54 9p-for-5.17-rc1: fixes, split 9p_net_fd, new reviewer
- fix possible uninitialized memory usage for setattr
 - fix fscache reading hole in a file just after it's been grown
 - split net/9p/trans_fd.c in its own module like other transports
   that module defaults to 9P_NET and is autoloaded if required so
   users should not be impacted
 - add Christian Schoenebeck to 9p reviewers
 - some more trivial cleanup
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAmHgt18ACgkQq06b7GqY
 5nAdUA//ZHFTIcnbTiVkqbw0YztxedTOhdGCWcYsszux0pNQ/ZCjbP5NxESWiFxs
 raYWcvE98Xvq4fbs8b+m7YKBJzWF+Km/v1MKfgvZZWFLZR3MfWiL8iojlsaUgG9U
 rBmEUyaTWw2COIvFN7EqnwT5mwzNCli5d3AzaAmgffWsHEi/+EVU35YX70ySUkjW
 nVf08oX3dBB425oArXOZApOZSVRsUr5YDSuQGiFHBL+hvPTrvPumu/AXbjLbTbmf
 NuUxu1Akw8/jhWNATLHzjCdzJzBSfF0zRs+oH9Qt8MKkUrlTfjxc/2MbQYL1p1IN
 84XxiG02ebw+Mx05cydP9/Ll7gOo2p6ORGXMHcoPIAMy6zFiCKo3TRdKDgmYDauC
 K8c3v+osNwl2GFn1+2XoQIWnqXb7bJ1debkFtWVEGOPd/Yr6CYCZyfiZamoPJXUO
 TjkoLAJXJGKlV66ZCuVeAsySdUxdtwbj2WxTliDUWtxvQ+m1jt06S3f/TbA7a9bB
 8aBhx7FKzQ/UL8zhm4+3WLPlWkoSUXhFSZZUknvhuaHFV/S1xglXox5OAQJrJMy+
 qOzmOjCg14T1TC2WkJlEsedLUH8ACU+XueAPT6uqSdA4rvQEVzk32zTm/GfFu3Q3
 0RhcGlW5kAAYBTBLXvmKsjyW2OmPCSycgbWCu3E8A/1gubbRE40=
 =o2Lc
 -----END PGP SIGNATURE-----

Merge tag '9p-for-5.17-rc1' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "Fixes, split 9p_net_fd, and new reviewer:

   - fix possible uninitialized memory usage for setattr

   - fix fscache reading hole in a file just after it's been grown

   - split net/9p/trans_fd.c in its own module like other transports.

     The new transport module defaults to 9P_NET and is autoloaded if
     required so users should not be impacted

   - add Christian Schoenebeck to 9p reviewers

   - some more trivial cleanup"

* tag '9p-for-5.17-rc1' of git://github.com/martinetd/linux:
  9p: fix enodata when reading growing file
  net/9p: show error message if user 'msize' cannot be satisfied
  MAINTAINERS: 9p: add Christian Schoenebeck as reviewer
  9p: only copy valid iattrs in 9P2000.L setattr implementation
  9p: Use BUG_ON instead of if condition followed by BUG.
  net/p9: load default transports
  9p/xen: autoload when xenbus service is available
  9p/trans_fd: split into dedicated module
  fs: 9p: remove unneeded variable
  9p/trans_virtio: Fix typo in the comment for p9_virtio_create()
2022-01-16 07:36:49 +02:00
David Howells
d7bdba1c81 9p, afs, ceph, nfs: Use current_is_kswapd() rather than gfpflags_allow_blocking()
In 9p, afs ceph, and nfs, gfpflags_allow_blocking() (which wraps a
test for __GFP_DIRECT_RECLAIM being set) is used to determine if
->releasepage() should wait for the completion of a DIO write to fscache
with something like:

	if (folio_test_fscache(folio)) {
		if (!gfpflags_allow_blocking(gfp) || !(gfp & __GFP_FS))
			return false;
		folio_wait_fscache(folio);
	}

Instead, current_is_kswapd() should be used instead.

Note that this is based on a patch originally by Zhaoyang Huang[1].  In
addition to extending it to the other network filesystems and putting it on
top of my fscache rewrite, it also needs to include linux/swap.h in a bunch
of places.  Can current_is_kswapd() be moved to linux/mm.h?

Changes
=======
ver #5:
 - Dropping the changes for cifs.

Originally-signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Co-developed-by: David Howells <dhowells@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Steve French <smfrench@gmail.com>
cc: Trond Myklebust <trond.myklebust@hammerspace.com>
cc: linux-cachefs@redhat.com
cc: v9fs-developer@lists.sourceforge.net
cc: linux-afs@lists.infradead.org
cc: ceph-devel@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/1638952658-20285-1-git-send-email-huangzhaoyang@gmail.com/ [1]
Link: https://lore.kernel.org/r/164021590773.640689.16777975200823659231.stgit@warthog.procyon.org.uk/ # v4
2022-01-11 22:27:42 +00:00
Dominique Martinet
19d1c32652 9p: fix enodata when reading growing file
Reading from a file that was just extended by a write, but the write had
not yet reached the server would return ENODATA as illustrated by this
command:
$ xfs_io -c 'open -ft test' -c 'w 4096 1000' -c 'r 0 1000'
wrote 1000/1000 bytes at offset 4096
1000.000000 bytes, 1 ops; 0.0001 sec (5.610 MiB/sec and 5882.3529 ops/sec)
pread: No data available

Fix this case by having netfs assume zeroes when reads from server come
short like AFS and CEPH do

Link: https://lkml.kernel.org/r/20220110111444.926753-1-asmadeus@codewreck.org
Cc: stable@vger.kernel.org
Fixes: eb497943fa ("9p: Convert to using the netfs helper lib to do reads and caching")
Co-authored-by: David Howells <dhowells@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-01-11 15:21:53 +09:00
David Howells
93c846143d 9p: Copy local writes to the cache when writing to the server
When writing to the server from v9fs_vfs_writepage(), copy the data to the
cache object too.

To make this possible, the cookie must have its active users count
incremented when the page is dirtied and kept incremented until we manage
to clean up all the pages.  This allows the writeback to take place after
the last file struct is released.

This is done by taking a use on the cookie in v9fs_set_page_dirty() if we
haven't already done so (controlled by the I_PINNING_FSCACHE_WB flag) and
dropping the pin in v9fs_write_inode() if __writeback_single_inode() clears
all the outstanding dirty pages (conveyed by the unpinned_fscache_wb flag
in the writeback_control struct).

Inode eviction must also clear the flag after truncating away all the
outstanding pages.

In the future this will be handled more gracefully by netfslib.

Changes
=======
ver #3:
 - Canonicalise the coherency data to make it endianness-independent.

ver #2:
 - Fix an unused-var warning due to CONFIG_9P_FSCACHE=n[1].

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dominique Martinet <asmadeus@codewreck.org>
cc: Eric Van Hensbergen <ericvh@gmail.com>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819667027.215744.13815687931204222995.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906978015.143852.10646669694345706328.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967180760.1823006.5831751873616248910.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021574522.640689.13849966660182529125.stgit@warthog.procyon.org.uk/ # v4
2022-01-10 11:53:25 +00:00
David Howells
24e42e32d3 9p: Use fscache indexing rewrite and reenable caching
Change the 9p filesystem to take account of the changes to fscache's
indexing rewrite and reenable caching in 9p.

The following changes have been made:

 (1) The fscache_netfs struct is no more, and there's no need to register
     the filesystem as a whole.

 (2) The session cookie is now an fscache_volume cookie, allocated with
     fscache_acquire_volume().  That takes three parameters: a string
     representing the "volume" in the index, a string naming the cache to
     use (or NULL) and a u64 that conveys coherency metadata for the
     volume.

     For 9p, I've made it render the volume name string as:

	"9p,<devname>,<cachetag>"

     where the cachetag is replaced by the aname if it wasn't supplied.

     This probably needs rethinking a bit as the aname can have slashes in
     it.  It might be better to hash the cachetag and use the hash or I
     could substitute commas for the slashes or something.

 (3) The fscache_cookie_def is no more and needed information is passed
     directly to fscache_acquire_cookie().  The cache no longer calls back
     into the filesystem, but rather metadata changes are indicated at
     other times.

     fscache_acquire_cookie() is passed the same keying and coherency
     information as before.

 (4) The functions to set/reset/flush cookies are removed and
     fscache_use_cookie() and fscache_unuse_cookie() are used instead.

     fscache_use_cookie() is passed a flag to indicate if the cookie is
     opened for writing.  fscache_unuse_cookie() is passed updates for the
     metadata if we changed it (ie. if the file was opened for writing).

     These are called when the file is opened or closed.

 (5) wait_on_page_bit[_killable]() is replaced with the specific wait
     functions for the bits waited upon.

 (6) I've got rid of some of the 9p-specific cache helper functions and
     called things like fscache_relinquish_cookie() directly as they'll
     optimise away if v9fs_inode_cookie() returns an unconditional NULL
     (which will be the case if CONFIG_9P_FSCACHE=n).

 (7) v9fs_vfs_setattr() is made to call fscache_resize() to change the size
     of the cache object.

Notes:

 (A) We should call fscache_invalidate() if we detect that the server's
     copy of a file got changed by a third party, but I don't know where to
     do that.  We don't need to do that when allocating the cookie as we
     get a check-and-invalidate when we initially bind to the cache object.

 (B) The copy-to-cache-on-writeback side of things will be handled in
     separate patch.

Changes
=======
ver #3:
 - Canonicalise the cookie key and coherency data to make them
   endianness-independent.

ver #2:
 - Use gfpflags_allow_blocking() rather than using flag directly.
 - fscache_acquire_volume() now returns errors.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dominique Martinet <asmadeus@codewreck.org>
cc: Eric Van Hensbergen <ericvh@gmail.com>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819664645.215744.1555314582005286846.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906975017.143852.3459573173204394039.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967178512.1823006.17377493641569138183.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021573143.640689.3977487095697717967.stgit@warthog.procyon.org.uk/ # v4
2022-01-10 11:53:06 +00:00
Christian Brauner
3cb6ee9914 9p: only copy valid iattrs in 9P2000.L setattr implementation
The 9P2000.L setattr method v9fs_vfs_setattr_dotl() copies struct iattr
values without checking whether they are valid causing unitialized
values to be copied. The 9P2000 setattr method v9fs_vfs_setattr() method
gets this right. Check whether struct iattr fields are valid first
before copying in v9fs_vfs_setattr_dotl() too and make sure that all
other fields are set to 0 apart from {g,u}id which should be set to
INVALID_{G,U}ID. This ensure that they can be safely sent over the wire
or printed for debugging later on.

Link: https://lkml.kernel.org/r/20211129114434.3637938-1-brauner@kernel.org
Link: https://lkml.kernel.org/r/000000000000a0d53f05d1c72a4c%40google.com
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: stable@kernel.org
Cc: v9fs-developer@lists.sourceforge.net
Reported-by: syzbot+dfac92a50024b54acaa4@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
[Dominique: do not set a/mtime with just ATTR_A/MTIME as discussed]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-01-10 10:00:09 +09:00
Zhang Mingyu
a7a427d154 9p: Use BUG_ON instead of if condition followed by BUG.
This issue was detected with the help of Coccinelle.

Link: https://lkml.kernel.org/r/20211112092547.9153-1-zhang.mingyu@zte.com.cn
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Zhang Mingyu <zhang.mingyu@zte.com.cn>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-01-10 10:00:09 +09:00
David Howells
2cee6fbb7f fscache: Remove the contents of the fscache driver, pending rewrite
Remove the code that comprises the fscache driver as it's going to be
substantially rewritten, with the majority of the code being erased in the
rewrite.

A small piece of linux/fscache.h is left as that is #included by a bunch of
network filesystems.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819578724.215744.18210619052245724238.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906884814.143852.6727245089843862889.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967077097.1823006.1377665951499979089.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021485548.640689.13876080567388696162.stgit@warthog.procyon.org.uk/ # v4
2022-01-07 09:22:19 +00:00
David Howells
01491a7565 fscache, cachefiles: Disable configuration
Disable fscache and cachefiles in Kconfig whilst it is rewritten.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819576672.215744.12444272479560406780.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906882835.143852.11073015983885872901.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967075113.1823006.277316290062782998.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021481179.640689.2004199594774033658.stgit@warthog.procyon.org.uk/ # v4
2022-01-07 09:21:44 +00:00
Changcheng Deng
90d6cf349c fs: 9p: remove unneeded variable
Fix the following coccicheck review:
./fs/9p/vfs_file.c: 117: 5-8: Unneeded variable

Remove unneeded variable used to store return value.

Link: https://lkml.kernel.org/r/20211109114343.132844-1-deng.changcheng@zte.com.cn
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-12-18 21:04:50 +09:00
David Howells
78525c74d9 netfs, 9p, afs, ceph: Use folios
Convert the netfs helper library to use folios throughout, convert the 9p
and afs filesystems to use folios in their file I/O paths and convert the
ceph filesystem to use just enough folios to compile.

With these changes, afs passes -g quick xfstests.

Changes
=======
ver #5:
 - Got rid of folio_end{io,_read,_write}() and inlined the stuff it does
   instead (Willy decided he didn't want this after all).

ver #4:
 - Fixed a bug in afs_redirty_page() whereby it didn't set the next page
   index in the loop and returned too early.
 - Simplified a check in v9fs_vfs_write_folio_locked()[1].
 - Undid a change to afs_symlink_readpage()[1].
 - Used offset_in_folio() in afs_write_end()[1].
 - Changed from using page_endio() to folio_end{io,_read,_write}()[1].

ver #2:
 - Add 9p foliation.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dominique Martinet <asmadeus@codewreck.org>
Tested-by: kafs-testing@auristor.com
cc: Matthew Wilcox (Oracle) <willy@infradead.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Ilya Dryomov <idryomov@gmail.com>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-afs@lists.infradead.org
cc: ceph-devel@vger.kernel.org
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/YYKa3bfQZxK5/wDN@casper.infradead.org/ [1]
Link: https://lore.kernel.org/r/2408234.1628687271@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/162877311459.3085614.10601478228012245108.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/162981153551.1901565.3124454657133703341.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163005745264.2472992.9852048135392188995.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163584187452.4023316.500389675405550116.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/163649328026.309189.1124218109373941936.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/163657852454.834781.9265101983152100556.stgit@warthog.procyon.org.uk/ # v5
2021-11-10 21:16:56 +00:00
Dominique Martinet
6e195b0f7c 9p: fix a bunch of checkpatch warnings
Sohaib Mohamed started a serie of tiny and incomplete checkpatch fixes but
seemingly stopped halfway -- take over and do most of it.
This is still missing net/9p/trans* and net/9p/protocol.c for a later
time...

Link: http://lkml.kernel.org/r/20211102134608.1588018-3-dominique.martinet@atmark-techno.com
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-04 21:04:25 +09:00
Dominique Martinet
b1843d2385 9p: set readahead and io size according to maxsize
having a readahead of 128k with a msize of 128k (with overhead) lead to
reading 124+4k everytime, making two roundtrips needlessly.

tune readahead according to msize when cache is enabled for better
performance

Link: http://lkml.kernel.org/r/20211104120323.2189376-1-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-04 21:04:04 +09:00
Dominique Martinet
05f975cd6a 9p p9mode2perm: remove useless strlcpy and check sscanf return code
This is also a checkpatch warning fix but this one might have implications
so keeping it separate

Link: http://lkml.kernel.org/r/20211102134608.1588018-5-dominique.martinet@atmark-techno.com
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:04 +09:00
Dominique Martinet
10c69a0d08 9p v9fs_parse_options: replace simple_strtoul with kstrtouint
This is also a checkpatch change, but this one might have more implications
so keeping this separate

Link: http://lkml.kernel.org/r/20211102134608.1588018-4-dominique.martinet@atmark-techno.com
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:04 +09:00
Dominique Martinet
024b7d6a43 9p: fix file headers
- add missing SPDX-License-Identifier
- remove (sometimes incorrect) file name from file header

Link: http://lkml.kernel.org/r/20211102134608.1588018-2-dominique.martinet@atmark-techno.com
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:04 +09:00
Sohaib Mohamed
9a268faa5f fs/9p: fix indentation and Add missing a blank line after declaration
Warning found by checkpatch.pl

Link: http://lkml.kernel.org/r/20210930220420.44150-1-sohaib.amhmd@gmail.com
Signed-off-by: Sohaib Mohamed <sohaib.amhmd@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:03 +09:00
Sohaib Mohamed
772712c581 fs/9p: fix warnings found by checkpatch.pl
Link: http://lkml.kernel.org/r/20211001063444.102330-1-sohaib.amhmd@gmail.com
Signed-off-by: Sohaib Mohamed <sohaib.amhmd@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
[Dominique: Fix the fixed indentation...]
2021-11-03 17:45:03 +09:00
Sohaib Mohamed
6d66ffc129 9p: fix minor indentation and codestyle
Warnings found by checkpatch.pl

Link: http://lkml.kernel.org/r/20210930235503.126033-1-sohaib.amhmd@gmail.com
Signed-off-by: Sohaib Mohamed <sohaib.amhmd@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:03 +09:00
Sohaib Mohamed
e4eeefbafc fs/9p: cleanup: opening brace at the beginning of the next line
Error found by checkpatch.pl

Link: http://lkml.kernel.org/r/20211001062454.99205-1-sohaib.amhmd@gmail.com
Signed-off-by: Sohaib Mohamed <sohaib.amhmd@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:02 +09:00
David Howells
eb497943fa 9p: Convert to using the netfs helper lib to do reads and caching
Convert the 9p filesystem to use the netfs helper lib to handle readpage,
readahead and write_begin, converting those into a common issue_op for the
filesystem itself to handle.  The netfs helper lib also handles reading
from fscache if a cache is available, and interleaving reads from both
sources.

This change also switches from the old fscache I/O API to the new one,
meaning that fscache no longer keeps track of netfs pages and instead does
async DIO between the backing files and the 9p file pagecache.  As a part
of this change, the handling of PG_fscache changes.  It now just means that
the cache has a write I/O operation in progress on a page (PG_locked
is used for a read I/O op).

Note that this is a cut-down version of the fscache rewrite and does not
change any of the cookie and cache coherency handling.

Changes
=======
ver #4:
  - Rebase on top of folios.
  - Don't use wait_on_page_bit_killable().

ver #3:
  - v9fs_req_issue_op() needs to terminate the subrequest.
  - v9fs_write_end() needs to call SetPageUptodate() a bit more often.
  - It's not CONFIG_{AFS,V9FS}_FSCACHE[1]
  - v9fs_init_rreq() should take a ref on the p9_fid and the cleanup should
    drop it [from Dominique Martinet].

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-and-tested-by: Dominique Martinet <asmadeus@codewreck.org>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/YUm+xucHxED+1MJp@codewreck.org/ [1]
Link: https://lore.kernel.org/r/163162772646.438332.16323773205855053535.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/163189109885.2509237.7153668924503399173.stgit@warthog.procyon.org.uk/ # rfc v2
Link: https://lore.kernel.org/r/163363943896.1980952.1226527304649419689.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/163551662876.1877519.14706391695553204156.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/163584179557.4023316.11089762304657644342.stgit@warthog.procyon.org.uk # rebase on folio
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-11-03 17:45:02 +09:00
David Howells
bc86803656 9p: Fix a bunch of kerneldoc warnings shown up by W=1
Fix a bunch of kerneldoc warnings shown up by W=1 in the 9p filesystem:

 (1) Add/remove/fix kerneldoc parameters descriptions.

 (2) Move __add_fid() from between v9fs_fid_add() and its comment.

 (3) 9p's caches_show() doesn't really make sense as an API function, so
     remove the kerneldoc annotation.  It's also not prefixed with 'v9fs_'.
     Also remove the kerneldoc markers from the 9p fscache wrappers.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Mauro Carvalho Chehab <mchehab@kernel.org>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-fsdevel@vger.kernel.org
cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/163214005516.2945267.7000234432243167892.stgit@warthog.procyon.org.uk/ # rfc v1
Link: https://lore.kernel.org/r/163281899704.2790286.9177774252843775348.stgit@warthog.procyon.org.uk/ # rfc v2
2021-10-04 22:07:46 +01:00
Linus Torvalds
815409a12c overlayfs update for 5.15
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCYTDKKAAKCRDh3BK/laaZ
 PG9PAQCUF0fdBlCKudwSEt5PV5xemycL9OCAlYCd7d4XbBIe9wEA6sVJL9J+OwV2
 aF0NomiXtJccE+S9+byjVCyqSzQJGQQ=
 =6L2Y
 -----END PGP SIGNATURE-----

Merge tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs update from Miklos Szeredi:

 - Copy up immutable/append/sync/noatime attributes (Amir Goldstein)

 - Improve performance by enabling RCU lookup.

 - Misc fixes and improvements

The reason this touches so many files is that the ->get_acl() method now
gets a "bool rcu" argument.  The ->get_acl() API was updated based on
comments from Al and Linus:

Link: https://lore.kernel.org/linux-fsdevel/CAJfpeguQxpd6Wgc0Jd3ks77zcsAv_bn0q17L3VNnnmPKu11t8A@mail.gmail.com/

* tag 'ovl-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: enable RCU'd ->get_acl()
  vfs: add rcu argument to ->get_acl() callback
  ovl: fix BUG_ON() in may_delete() when called from ovl_cleanup()
  ovl: use kvalloc in xattr copy-up
  ovl: update ctime when changing fileattr
  ovl: skip checking lower file's i_writecount on truncate
  ovl: relax lookup error on mismatch origin ftype
  ovl: do not set overlay.opaque for new directories
  ovl: add ovl_allow_offline_changes() helper
  ovl: disable decoding null uuid with redirect_dir
  ovl: consistent behavior for immutable/append-only inodes
  ovl: copy up sync/noatime fileattr flags
  ovl: pass ovl_fs to ovl_check_setxattr()
  fs: add generic helper for filling statx attribute flags
2021-09-02 09:21:27 -07:00
Linus Torvalds
87045e6546 for-5.15-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmEs2NIACgkQxWXV+ddt
 WDsJMQ/+PJ/yXfI85mAeAzTJLWQ0zD6YO3iBhf3wOeyychWC4on435pj+zW8zR/U
 /bix25ygoWF4MvGF6p0uyv4Z5mnvkZXE5lapUcJu6wXG7se1QRPH0broTh05IBXK
 SnT93Eb9RexaiNFk7DVma9XkviqZ/ZISPtkJ9wYrfIba7j/U/wa+PtEFS7wk58hP
 rFQXgV64xm/pcP28YYHfOkCjdyUMdJrnBUvfKOlX6d94lmYbP5lyiTL+XJEXExzN
 wPakD0UsnXPr4TRvf+YRTPeFHPPUgyORII7otVUOKmGywWtcJrELX8rXFoW+6GwB
 dzZIcSYXHUxU5UrtMbZgiztVBJ+bQY5juYMIrj13eYOMYkijxAqPP84iDO15+TSV
 zNqyAVjUglHCGUGjhSpAxnAmtp+IJTZfVAWcvIKq3VqvJtb8tssQsk9bqFjH1xlH
 qNJLE57CYe3tjw05K9y0keMh2iJWRWkXZYkgI/zjwo5nreemobpN+3fO4yneVLh7
 ecdBmSl/JVSzAB1NamLOCZNGZLUqiiuTvZlJtI6ZsekrN1+4A6QzVcU/MGjSYL1v
 C7W0hK0LF+e3xIBkxTKVq8noolsgbmlWacxJq8fZq9HwZy5IVJOVm9STDlCuLaIo
 gPr0V0itkclcsMU0CHTyCjMsfuHYUwJZXwg93wKfJf5UCzS4OWU=
 =ALO9
 -----END PGP SIGNATURE-----

Merge tag 'for-5.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "The highlights of this round are integrations with fs-verity and
  idmapped mounts, the rest is usual mix of minor improvements, speedups
  and cleanups.

  There are some patches outside of btrfs, namely updating some VFS
  interfaces, all straightforward and acked.

  Features:

   - fs-verity support, using standard ioctls, backward compatible with
     read-only limitation on inodes with previously enabled fs-verity

   - idmapped mount support

   - make mount with rescue=ibadroots more tolerant to partially damaged
     trees

   - allow raid0 on a single device and raid10 on two devices,
     degenerate cases but might be useful as an intermediate step during
     conversion to other profiles

   - zoned mode block group auto reclaim can be disabled via sysfs knob

  Performance improvements:

   - continue readahead of node siblings even if target node is in
     memory, could speed up full send (on sample test +11%)

   - batching of delayed items can speed up creating many files

   - fsync/tree-log speedups
       - avoid unnecessary work (gains +2% throughput, -2% run time on
         sample load)
       - reduced lock contention on renames (on dbench +4% throughput,
         up to -30% latency)

  Fixes:

   - various zoned mode fixes

   - preemptive flushing threshold tuning, avoid excessive work on
     almost full filesystems

  Core:

   - continued subpage support, preparation for implementing remaining
     features like compression and defragmentation; with some
     limitations, write is now enabled on 64K page systems with 4K
     sectors, still considered experimental
       - no readahead on compressed reads
       - inline extents disabled
       - disabled raid56 profile conversion and mount

   - improved flushing logic, fixing early ENOSPC on some workloads

   - inode flags have been internally split to read-only and read-write
     incompat bit parts, used by fs-verity

   - new tree items for fs-verity
       - descriptor item
       - Merkle tree item

   - inode operations extended to be namespace-aware

   - cleanups and refactoring

  Generic code changes:

   - fs: new export filemap_fdatawrite_wbc

   - fs: removed sync_inode

   - block: bio_trim argument type fixups

   - vfs: add namespace-aware lookup"

* tag 'for-5.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (114 commits)
  btrfs: reset replace target device to allocation state on close
  btrfs: zoned: fix ordered extent boundary calculation
  btrfs: do not do preemptive flushing if the majority is global rsv
  btrfs: reduce the preemptive flushing threshold to 90%
  btrfs: tree-log: check btrfs_lookup_data_extent return value
  btrfs: avoid unnecessarily logging directories that had no changes
  btrfs: allow idmapped mount
  btrfs: handle ACLs on idmapped mounts
  btrfs: allow idmapped INO_LOOKUP_USER ioctl
  btrfs: allow idmapped SUBVOL_SETFLAGS ioctl
  btrfs: allow idmapped SET_RECEIVED_SUBVOL ioctls
  btrfs: relax restrictions for SNAP_DESTROY_V2 with subvolids
  btrfs: allow idmapped SNAP_DESTROY ioctls
  btrfs: allow idmapped SNAP_CREATE/SUBVOL_CREATE ioctls
  btrfs: check whether fsgid/fsuid are mapped during subvolume creation
  btrfs: allow idmapped permission inode op
  btrfs: allow idmapped setattr inode op
  btrfs: allow idmapped tmpfile inode op
  btrfs: allow idmapped symlink inode op
  btrfs: allow idmapped mkdir inode op
  ...
2021-08-31 09:41:22 -07:00
Josef Bacik
25d23cd016 9p: migrate from sync_inode to filemap_fdatawrite_wbc
We're going to remove sync_inode, so migrate to filemap_fdatawrite_wbc
instead.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:07 +02:00
Jeff Layton
f7e33bdbd6 fs: remove mandatory file locking support
We added CONFIG_MANDATORY_FILE_LOCKING in 2015, and soon after turned it
off in Fedora and RHEL8. Several other distros have followed suit.

I've heard of one problem in all that time: Someone migrated from an
older distro that supported "-o mand" to one that didn't, and the host
had a fstab entry with "mand" in it which broke on reboot. They didn't
actually _use_ mandatory locking so they just removed the mount option
and moved on.

This patch rips out mandatory locking support wholesale from the kernel,
along with the Kconfig option and the Documentation file. It also
changes the mount code to ignore the "mand" mount option instead of
erroring out, and to throw a big, ugly warning.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-08-23 06:15:36 -04:00
Miklos Szeredi
0cad624662 vfs: add rcu argument to ->get_acl() callback
Add a rcu argument to the ->get_acl() callback to allow
get_cached_acl_rcu() to call the ->get_acl() method in the next patch.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2021-08-18 22:08:24 +02:00
Linus Torvalds
e22e983279 9p for 5.13-rc1
an error handling fix and const optimization
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAmCVJa4ACgkQq06b7GqY
 5nDUwxAAkBS34dEfhWgENugMY73Rj1sZ7VAN6HqpT9+7KrQHPXSfCnVac+q1/JzA
 KuWg1zJaUeYt8VyDMUDPR4l4u6X7NM7ED7qwYlVolP4zfRtYgvo7ZbGHTqryV6wl
 A0/TIznPAYphOWYqiLPbtuUfmDYQedsGR8CC55jR3FIA0JBMj28b7m5aSSigDUU0
 SX5Erkq6PPRT5yAStPQBhwcpckceo+cVpfdO+9llZ35BfZVxdhMKudU54XIOiwX6
 1AJk+naHeLN4cCZJeWiiMHMKfBdylAJV2/dG0Po2SRo2nsytTC1eCRSvMtqZOf3m
 T0cEM6LFJgiqvG0c3w2At1ZkhDTZmyKapMgexRMsuxWhy3InAvfpXIurGuLkdI5T
 J99cd+LDp5bvH8u3tk3QSzYWp3ZACaW16X4rlV+iBk9huA0EiSHNVdTGU8tvEkPj
 s9gQPgIzgxdkDZmzTvsJDiPASORblJiLdmuvz4vojRey7Bqr/1ilZ2cnX/OjDA6p
 d4K73VWG3YSecm63mpfv8KCxAFUaQT09/oPBNDIJ/SYZTOUaunoBse3EOvUkX5Od
 Ar2ehkPOt9Q8Gu3N2F194Rd30vbADiYMezPkTdY0NdJXI6sUUa2SJj0nEsbMqNIg
 wauDYYzyuRp+k0J6+Oj3tVH074a8/q6trPzuA6C5MuyPx/kgJ00=
 =B3Ef
 -----END PGP SIGNATURE-----

Merge tag '9p-for-5.13-rc1' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "An error handling fix and constification"

* tag '9p-for-5.13-rc1' of git://github.com/martinetd/linux:
  fs: 9p: fix v9fs_file_open writeback fid error check
  9p: Constify static struct v9fs_attr_group
2021-05-07 11:18:52 -07:00
Yang Yingliang
f8b139e2f2 fs: 9p: fix v9fs_file_open writeback fid error check
IS_ERR() and PTR_ERR() use wrong pointer, it should be
writeback_fid, fix it.

Link: http://lkml.kernel.org/r/20210330130632.1054357-1-yangyingliang@huawei.com
Fixes: 5bfe97d738 ("9p: Fix writeback fid incorrectly being attached to dentry")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
[Dominique: adjusted commit summary]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-03-31 07:02:47 +09:00
Rikard Falkeborn
0dae52282a 9p: Constify static struct v9fs_attr_group
The only usage of v9fs_attr_group is to pass its address to
sysfs_create_group() and sysfs_create_group(), both which takes pointers
to const struct attribute_group. Make it const to allow the compiler to
put it in read-only memory.

Link: http://lkml.kernel.org/r/20210108224650.25872-1-rikard.falkeborn@gmail.com
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2021-03-31 07:02:46 +09:00
Al Viro
b577d0cd21 9p: missing chunk of "fs/9p: Don't update file type when updating file attributes"
In commit 45089142b1 Aneesh had missed one (admittedly, very unlikely
to hit) case in v9fs_stat2inode_dotl().  However, the same considerations
apply there as well - we have no business whatsoever to change ->i_rdev
or the file type.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-12 22:15:22 -05:00
Al Viro
6e3e2c4362 new helper: inode_wrong_type()
inode_wrong_type(inode, mode) returns true if setting inode->i_mode
to given value would've changed the inode type.  We have enough of
those checks open-coded to make a helper worthwhile.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:35 -05:00
Linus Torvalds
5ceabb6078 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted stuff pile - no common topic here"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  whack-a-mole: don't open-code iminor/imajor
  9p: fix misuse of sscanf() in v9fs_stat2inode()
  audit_alloc_mark(): don't open-code ERR_CAST()
  fs/inode.c: make inode_init_always() initialize i_ino to 0
  vfs: don't unnecessarily clone write access for writable fds
2021-02-27 08:07:12 -08:00
Al Viro
9652c73246 9p: fix misuse of sscanf() in v9fs_stat2inode()
1) sscanf() return value needs to be checked, damnit
2) sscanf() is perfectly capable of checking for fixed prefix,
no need for that %13s + strncmp with constant string.
3) st->extension is a valid string; no need for voodoo with
str*cpy() there.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-02-23 10:25:28 -05:00
Christian Brauner
549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner
0d56a4518d
stat: handle idmapped mounts
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner
e65ce2a50c
acl: handle idmapped mounts
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.

The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.

In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.

Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner
2f221d6f7b
attr: handle idmapped mounts
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.

Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Christian Brauner
21cb47be6f
inode: make init and permission helpers idmapped mount aware
The inode_owner_or_capable() helper determines whether the caller is the
owner of the inode or is capable with respect to that inode. Allow it to
handle idmapped mounts. If the inode is accessed through an idmapped
mount it according to the mount's user namespace. Afterwards the checks
are identical to non-idmapped mounts. If the initial user namespace is
passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Similarly, allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the
fsuid and fsgid of the caller from the mount's user namespace. If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Linus Torvalds
70990afa34 9p for 5.11-rc1
- fix long-standing limitation on open-unlink-fop pattern
 - add refcount to p9_fid (fixes the above and will allow for more
 cleanups and simplifications in the future)
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAl/gWOYACgkQq06b7GqY
 5nBcHxAArtfxZ4wGa+OMoWt19UvF0bUeYUYdy75rp6awpXmQyMfMZY9oOrZ9L+St
 mS3oLd8Mq7MeJQ+iGKPPOX+085aNhRtxjQOiHlv02fi09zVyNqj1vptq+rTRkKZL
 8KTs+wYSIX2x1WensDBdohYFiWf87vCWyywpQ/1Vm0585mI8B88N3/H5EpkLbPZn
 1bgXkakgd2hS+rKu6vJGV8lCJ8eKOSpQ3WUK0WQhY6ysJEL9dbl00qyNQ4kq2UgI
 i3CpWC/86297KJOehPmegpVwqTIL5wrCkhQy7sNxDkR9E4Q3VoKTNSrnRDtBI0x/
 mRCEnc/2Pf76Zv3LpGXnLFSnDLTQaO842Hla92RZJCcHaDtGDwV9Znq6sZgn+pdV
 wlEpT383s+7AC/X1EFvLPMr5PHrEM1KW25YEYQI78X2hh8G+utW5p3+vu70b0PyT
 Z7P9yBW4aU4cZb3XcZZihatZG2P1LxHyjNMmn4YBdUeQuitdiJGc2KwjVyKXi9PX
 +t6xxI+YAIhu/5I9fRtOoIDQNTjsRRE+4FzRKd2kvxW5Z5sV/bZCf6CHnQ2uKYVP
 fEMYd0GhjrUABbJPLLdFlBXaV+yigvwKtABDnJ5KSA9NlDSVBGewTRa2I+9DoclL
 yQS4hELuvQsUNCo4AkICixo9vABt0j1OhXlo+B0WVk8Ilh9Wxpc=
 =DKlc
 -----END PGP SIGNATURE-----

Merge tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux

Pull 9p update from Dominique Martinet:

 - fix long-standing limitation on open-unlink-fop pattern

 - add refcount to p9_fid (fixes the above and will allow for more
   cleanups and simplifications in the future)

* tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux:
  9p: Remove unnecessary IS_ERR() check
  9p: Uninitialized variable in v9fs_writeback_fid()
  9p: Fix writeback fid incorrectly being attached to dentry
  9p: apply review requests for fid refcounting
  9p: add refcount to p9_fid struct
  fs/9p: search open fids first
  fs/9p: track open fids
  fs/9p: fix create-unlink-getattr idiom
2020-12-21 10:28:02 -08:00
Dominique Martinet
960f4f8a4e fs: 9p: add generic splice_write file operation
The default splice operations got removed recently, add it back to 9p
with iter_file_splice_write like many other filesystems do.

Link: http://lkml.kernel.org/r/1606837496-21717-1-git-send-email-asmadeus@codewreck.org
Fixes: 36e2c7421f ("fs: don't allow splice read/write without explicit ops")
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-12-01 21:40:47 +01:00
Toke Høiland-Jørgensen
cf03f316ad fs: 9p: add generic splice_read file operations
The v9fs file operations were missing the splice_read operations, which
breaks sendfile() of files on such a filesystem. I discovered this while
trying to load an eBPF program using iproute2 inside a 'virtme' environment
which uses 9pfs for the virtual file system. iproute2 relies on sendfile()
with an AF_ALG socket to hash files, which was erroring out in the virtual
environment.

Since generic_file_splice_read() seems to just implement splice_read in
terms of the read_iter operation, I simply added the generic implementation
to the file operations, which fixed the error I was seeing. A quick grep
indicates that this is what most other file systems do as well.

Link: http://lkml.kernel.org/r/20201201135409.55510-1-toke@redhat.com
Fixes: 36e2c7421f ("fs: don't allow splice read/write without explicit ops")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-12-01 17:53:49 +01:00
Dan Carpenter
cfd1d0f524 9p: Remove unnecessary IS_ERR() check
The "fid" variable can't be an error pointer so there is no need to
check.  The code is slightly cleaner if we move the increment before
the break and remove the NULL check as well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-12-01 08:19:02 +01:00
Dan Carpenter
dfd375864a 9p: Uninitialized variable in v9fs_writeback_fid()
If v9fs_fid_lookup_with_uid() fails then "fid" is not initialized.

The v9fs_fid_lookup_with_uid() can't return NULL.  If it returns an
error pointer then we can still pass that to clone_fid() and it will
return the error pointer back again.

Fixes: 6636b6dcc3 ("9p: add refcount to p9_fid struct")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-12-01 08:18:57 +01:00
Dominique Martinet
5bfe97d738 9p: Fix writeback fid incorrectly being attached to dentry
v9fs_dir_release needs fid->ilist to have been initialized for filp's
fid, not the inode's writeback fid's.

With refcounting this can be improved on later but this appears to fix
null deref issues.

Link: http://lkml.kernel.org/r/1605802012-31133-3-git-send-email-asmadeus@codewreck.org
Fixes: 6636b6dcc3 ("fs/9p: track open fids")
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-11-19 17:22:28 +01:00
Dominique Martinet
ff5e72ebef 9p: apply review requests for fid refcounting
Fix style issues in parent commit ("apply review requests for fid
refcounting"), no functional change.

Link: http://lkml.kernel.org/r/1605802012-31133-2-git-send-email-asmadeus@codewreck.org
Fixes: 6636b6dcc3 ("9p: add refcount to p9_fid struct")
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-11-19 17:21:34 +01:00
Jianyong Wu
6636b6dcc3 9p: add refcount to p9_fid struct
Fix race issue in fid contention.

Eric's and Greg's patch offer a mechanism to fix open-unlink-f*syscall
bug in 9p. But there is race issue in fid parallel accesses.
As Greg's patch stores all of fids from opened files into according inode,
so all the lookup fid ops can retrieve fid from inode preferentially. But
there is no mechanism to handle the fid contention issue. For example,
there are two threads get the same fid in the same time and one of them
clunk the fid before the other thread ready to discard the fid. In this
scenario, it will lead to some fatal problems, even kernel core dump.

I introduce a mechanism to fix this race issue. A counter field introduced
into p9_fid struct to store the reference counter to the fid. When a fid
is allocated from the inode or dentry, the counter will increase, and
will decrease at the end of its occupation. It is guaranteed that the
fid won't be clunked before the reference counter go down to 0, then
we can avoid the clunked fid to be used.

tests:
race issue test from the old test case:
for file in {01..50}; do touch f.${file}; done
seq 1 1000 | xargs -n 1 -P 50 -I{} cat f.* > /dev/null

open-unlink-f*syscall test:
I have tested for f*syscall include: ftruncate fstat fchown fchmod faccessat.

Link: http://lkml.kernel.org/r/20200923141146.90046-5-jianyong.wu@arm.com
Fixes: 478ba09edc ("fs/9p: search open fids first")
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-11-19 17:20:39 +01:00
Greg Kurz
478ba09edc fs/9p: search open fids first
A previous patch fixed the "create-unlink-getattr" idiom: if getattr is
called on an unlinked file, we try to find an open fid attached to the
corresponding inode.

We have a similar issue with file permissions and setattr:

open("./test.txt", O_RDWR|O_CREAT, 0666) = 4
chmod("./test.txt", 0)                  = 0
truncate("./test.txt", 0)               = -1 EACCES (Permission denied)
ftruncate(4, 0)                         = -1 EACCES (Permission denied)

The failure is expected with truncate() but not with ftruncate().

This happens because the lookup code does find a matching fid in the
dentry list. Unfortunately, this is not an open fid and the server
will be forced to rely on the path name, rather than on an open file
descriptor. This is the case in QEMU: the setattr operation will use
truncate() and fail because of bad write permissions.

This patch changes the logic in the lookup code, so that we consider
open fids first. It gives a chance to the server to match this open
fid to an open file descriptor and use ftruncate() instead of truncate().
This does not change the current behaviour for truncate() and other
path name based syscalls, since file permissions are checked earlier
in the VFS layer.

With this patch, we get:

open("./test.txt", O_RDWR|O_CREAT, 0666) = 4
chmod("./test.txt", 0)                  = 0
truncate("./test.txt", 0)               = -1 EACCES (Permission denied)
ftruncate(4, 0)                         = 0

Link: http://lkml.kernel.org/r/20200923141146.90046-4-jianyong.wu@arm.com
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-11-03 09:29:56 +01:00
Greg Kurz
987a648509 fs/9p: track open fids
This patch adds accounting of open fids in a list hanging off the i_private
field of the corresponding inode. This allows faster lookups compared to
searching the full 9p client list.

The lookup code is modified accordingly.

Link: http://lkml.kernel.org/r/20200923141146.90046-3-jianyong.wu@arm.com
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-11-03 09:29:46 +01:00
Eric Van Hensbergen
154372e67d fs/9p: fix create-unlink-getattr idiom
Fixes several outstanding bug reports of not being able to getattr from an
open file after an unlink.  This patch cleans up transient fids on an unlink
and will search open fids on a client if it detects a dentry that appears to
have been unlinked.  This search is necessary because fstat does not pass fd
information through the VFS API to the filesystem, only the dentry which for
9p has an imperfect match to fids.

Inherent in this patch is also a fix for the qid handling on create/open
which apparently wasn't being set correctly and was necessary for the search
to succeed.

A possible optimization over this fix is to include accounting of open fids
with the inode in the private data (in a similar fashion to the way we track
transient fids with dentries).  This would allow a much quicker search for
a matching open fid.

(changed v9fs_fid_find_global to v9fs_fid_find_inode in comment)

Link: http://lkml.kernel.org/r/20200923141146.90046-2-jianyong.wu@arm.com
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-11-03 09:29:31 +01:00
Linus Torvalds
0eac1102e9 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted stuff all over the place (the largest group here is
  Christoph's stat cleanups)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: remove KSTAT_QUERY_FLAGS
  fs: remove vfs_stat_set_lookup_flags
  fs: move vfs_fstatat out of line
  fs: implement vfs_stat and vfs_lstat in terms of vfs_fstatat
  fs: remove vfs_statx_fd
  fs: omfs: use kmemdup() rather than kmalloc+memcpy
  [PATCH] reduce boilerplate in fsid handling
  fs: Remove duplicated flag O_NDELAY occurring twice in VALID_OPEN_FLAGS
  selftests: mount: add nosymfollow tests
  Add a "nosymfollow" mount option.
2020-10-24 12:26:05 -07:00
Linus Torvalds
334d431f65 9p pull request for inclusion in 5.10
A couple of small fixes (loff_t overflow on 32bit, syzbot uninitialized
 variable warning) and code cleanup (xen)
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAl+Rc/EACgkQq06b7GqY
 5nACqxAAnrPj6uA4IQGCQCbRKetkidZrIGre/8RyEAyfxj+8gV0POYp/1SFokAu+
 RzNkeDgKXkV8L/6BEc/XTi/Iy2HGlPOQLjpBcDLwOIe+ZSlXYK544zUqs20W8/ZH
 NHtUY9rvgEWaTyYCi0wjS51xqBs2/Km4OIUKj7OZHXx9rWmpPX/6xwgcR4tNAWEJ
 7AYkq9G0OiDbY9TaHRK0dOmVq1Xs+H3s5Ci4FMh/uFcQBI3UgfpYAegqTiMh8/AF
 aWgtMdidHaBIWdzb1W4UbBXVd14dFfcIqMTzstFO+mElO4VtQCAQtC16cJX9Dqgh
 2YQxZgF5uVAi3DogHLDT0iT6RiqJrU8WeDLfOq8AuOy29l5jlGB6y1GppmS4z0DK
 sw+fy0lMH9q2ahbJs3RMk05m9vK8L9HCjqnMbTD0TohtkEEWyhHJ2RadtkDnRAL+
 Vy+tlfENloVW4zJIFT8RI5pLXqLG4NGV5Tlp5D//5abV1V8uEeVFHe97JTBMsafi
 FAGWqghPPxRB7UhtbnNHiIGDClOctT9y+SY0mxIkq0Bw+26K5G/eXWwF+Wgelfrs
 n0nCrbi5rVdJJhcrZid4r/tUDpXydxgQmrXV8jsgpHH22B02WXKtAzcgWJsB9vec
 syicGh9Shr4cF1S0Rq/Brgl47WGwHjufsvWSwnukvZ1+X4Rs9Qw=
 =ONeq
 -----END PGP SIGNATURE-----

Merge tag '9p-for-5.10-rc1' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "A couple of small fixes (loff_t overflow on 32bit, syzbot
  uninitialized variable warning) and code cleanup (xen)"

* tag '9p-for-5.10-rc1' of git://github.com/martinetd/linux:
  net: 9p: initialize sun_server.sun_path to have addr's value only when addr is valid
  9p/xen: Fix format argument warning
  9P: Cast to loff_t before multiplying
2020-10-22 09:33:20 -07:00
Matthew Wilcox (Oracle)
f5f7ab168b 9P: Cast to loff_t before multiplying
On 32-bit systems, this multiplication will overflow for files larger
than 4GB.

Link: http://lkml.kernel.org/r/20201004180428.14494-2-willy@infradead.org
Cc: stable@vger.kernel.org
Fixes: fb89b45cdf ("9P: introduction of a new cache=mmap model.")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-10-07 23:57:30 +02:00
Christoph Hellwig
f56753ac2a bdi: replace BDI_CAP_NO_{WRITEBACK,ACCT_DIRTY} with a single flag
Replace the two negative flags that are always used together with a
single positive flag that indicates the writeback capability instead
of two related non-capabilities.  Also remove the pointless wrappers
to just check the flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24 13:43:39 -06:00
Christoph Hellwig
55b2598e84 bdi: initialize ->ra_pages and ->io_pages in bdi_init
Set up a readahead size by default, as very few users have a good
reason to change it.  This means code, ecryptfs, and orangefs now
set up the values while they were previously missing it, while ubifs,
mtd and vboxsf manually set it to 0 to avoid readahead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Richard Weinberger <richard@nod.at> [ubifs, mtd]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24 13:43:39 -06:00
Al Viro
6d1349c769 [PATCH] reduce boilerplate in fsid handling
Get rid of boilerplate in most of ->statfs()
instances...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-18 16:45:50 -04:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

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

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Li Heng
2ed0b75781 9p: Remove unneeded cast from memory allocation
Remove kmem_cache_alloc return value cast.

Coccinelle emits the following warning:

./fs/9p/vfs_inode.c:226:12-29: WARNING: casting value returned by memory allocation function to (struct v9fs_inode *) is useless.

Link: http://lkml.kernel.org/r/1596013140-49744-1-git-send-email-liheng40@huawei.com
Signed-off-by: Li Heng <liheng40@huawei.com>
[Dominique: commit message wording]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-07-31 07:28:25 +02:00
Jianyong Wu
aab6c873cf 9p: remove unused code in 9p
These codes have been commented out since 2007 and lay in kernel
since then. So, it's better to remove them.

Link: http://lkml.kernel.org/r/20200628074337.45895-1-jianyong.wu@arm.com
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-07-19 14:58:47 +02:00
Zheng Bin
cb0aae0e31 9p: Fix memory leak in v9fs_mount
v9fs_mount
  v9fs_session_init
    v9fs_cache_session_get_cookie
      v9fs_random_cachetag                     -->alloc cachetag
      v9ses->fscache = fscache_acquire_cookie  -->maybe NULL
  sb = sget                                    -->fail, goto clunk
clunk_fid:
  v9fs_session_close
    if (v9ses->fscache)                        -->NULL
      kfree(v9ses->cachetag)

Thus memleak happens.

Link: http://lkml.kernel.org/r/20200615012153.89538-1-zhengbin13@huawei.com
Fixes: 60e78d2c99 ("9p: Add fscache support to 9p")
Cc: <stable@vger.kernel.org> # v2.6.32+
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-07-19 14:58:47 +02:00
Jianyong Wu
6624664160 9p: retrieve fid from file when file instance exist.
In the current setattr implementation in 9p, fid is always retrieved
from dentry no matter file instance exists or not. If so, there may be
some info related to opened file instance dropped. So it's better
to retrieve fid from file instance when it is passed to setattr.

for example:
fd=open("tmp", O_RDWR);
ftruncate(fd, 10);

The file context related with the fd will be lost as fid is always
retrieved from dentry, then the backend can't get the info of
file context. It is against the original intention of user and
may lead to bug.

Link: http://lkml.kernel.org/r/20200710101548.10108-1-jianyong.wu@arm.com
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2020-07-19 14:58:47 +02:00
Sergey Alirzaev
52cbee2a57 9p: read only once on O_NONBLOCK
A proper way to handle O_NONBLOCK would be making the requests and
responses happen asynchronously, but this would require serious code
refactoring.

Link: http://lkml.kernel.org/r/20200205003457.24340-2-l29ah@cock.li
Signed-off-by: Sergey Alirzaev <l29ah@cock.li>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2020-03-27 09:29:56 +00:00
zhengbin
5195881739 9p: Remove unneeded semicolon
Fixes coccicheck warning:

fs/9p/vfs_inode.c:146:3-4: Unneeded semicolon

Link: http://lkml.kernel.org/r/1576752517-58292-1-git-send-email-zhengbin13@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2020-03-27 09:29:56 +00:00
Krzysztof Kozlowski
1f5bd6a202 9p: Fix Kconfig indentation
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /\t/' -i */Kconfig

Link: http://lkml.kernel.org/r/20191120134340.16770-1-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2020-03-27 09:29:56 +00:00
Linus Torvalds
9977b1a714 9p pull request for inclusion in 5.4
Small fixes all around:
  - avoid overlayfs copy-up for PRIVATE mmaps
  - KUMSAN uninitialized warning for transport error
  - one syzbot memory leak fix in 9p cache
  - internal API cleanup for v9fs_fill_super
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAl2OG0MACgkQq06b7GqY
 5nB21Q/+P4kD+wBg4d1b74Mf+oK2p2cSvCnYHcwMgkRsuyFgu7JXLSuRy2DLlAa4
 F+92x0jvit+yUy8bFqlEsSGGmE/dZC3WfpBOVChZRT/9ZLcxNasowtGDaySrX1e1
 tmx5QfYsNL840Cv8Vfos4QJjze1oE6RmSCUUO4KyC250PO/jxEgWGVPv1S8LfTUb
 KyhkcKlJ+TCqEON9nZ+CrQ4rndHNc7LxtBjVR0M03UYW55kYAhMLSj/AWqKA5I0q
 tARlTSgHHRdj4EJvWvLw7INg7BuvTuuyIzCIo/RfpUvijTDyLXFQI3qgtXosKLSq
 wuOacq8ykDRv8nvpLJ98daCw0pQOF2Qw40niFfl8Y7AxnaXggMI+UsVX/BnigVWX
 E6kaJm6d/YERee/f7aBsJkjKbwRqO7tMbNDrbK2/AzAaZo92dnB5nsEJnvKtCdjl
 aylBujCJq/DPp/SOf0Rl8mr24GdYVIk04hvqpxr4X6a/sacO3EUMh8GkGD7muY63
 axbYildLQHyChEn0TNdicFFrVie3A984eiK8sht+visd7c5QRm9iu1lsYtXdVGuz
 0OvSRtJuTDCTs6s1DhhVnez9luzH4VZJAj0RYJjcF1M4tzy0sKWUSSUf3RUbyxmY
 bocklihTlI5UzZfCP/wChXJ26+QrmcL7j0PrKA0NJy7ooFyT5eI=
 =VBrx
 -----END PGP SIGNATURE-----

Merge tag '9p-for-5.4' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "Some of the usual small fixes and cleanup.

  Small fixes all around:
   - avoid overlayfs copy-up for PRIVATE mmaps
   - KUMSAN uninitialized warning for transport error
   - one syzbot memory leak fix in 9p cache
   - internal API cleanup for v9fs_fill_super"

* tag '9p-for-5.4' of git://github.com/martinetd/linux:
  9p/vfs_super.c: Remove unused parameter data in v9fs_fill_super
  9p/cache.c: Fix memory leak in v9fs_cache_session_get_cookie
  9p: Transport error uninitialized
  9p: avoid attaching writeback_fid on mmap with type PRIVATE
2019-09-27 15:10:34 -07:00
Bharath Vedartham
aafee43b72 9p/vfs_super.c: Remove unused parameter data in v9fs_fill_super
v9fs_fill_super has a param 'void *data' which is unused in the
function.

This patch removes the 'void *data' param in v9fs_fill_super and changes
the parameters in all function calls of v9fs_fill_super.

Link: http://lkml.kernel.org/r/20190523165619.GA4209@bharath12345-Inspiron-5559
Signed-off-by: Bharath Vedartham <linux.bhar@gmail.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2019-09-03 11:10:13 +00:00
Bharath Vedartham
962a991c5d 9p/cache.c: Fix memory leak in v9fs_cache_session_get_cookie
v9fs_cache_session_get_cookie assigns a random cachetag to v9ses->cachetag,
if the cachetag is not assigned previously.

v9fs_random_cachetag allocates memory to v9ses->cachetag with kmalloc and uses
scnprintf to fill it up with a cachetag.

But if scnprintf fails, v9ses->cachetag is not freed in the current
code causing a memory leak.

Fix this by freeing v9ses->cachetag it v9fs_random_cachetag fails.

This was reported by syzbot, the link to the report is below:
https://syzkaller.appspot.com/bug?id=f012bdf297a7a4c860c38a88b44fbee43fd9bbf3

Link: http://lkml.kernel.org/r/20190522194519.GA5313@bharath12345-Inspiron-5559
Reported-by: syzbot+3a030a73b6c1e9833815@syzkaller.appspotmail.com
Signed-off-by: Bharath Vedartham <linux.bhar@gmail.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2019-09-03 11:07:39 +00:00
Chengguang Xu
c87a37ebd4 9p: avoid attaching writeback_fid on mmap with type PRIVATE
Currently on mmap cache policy, we always attach writeback_fid
whether mmap type is SHARED or PRIVATE. However, in the use case
of kata-container which combines 9p(Guest OS) with overlayfs(Host OS),
this behavior will trigger overlayfs' copy-up when excute command
inside container.

Link: http://lkml.kernel.org/r/20190820100325.10313-1-cgxu519@zoho.com.cn
Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2019-09-03 10:56:32 +00:00
Deepa Dinamani
d5c6e2d518 9p: Fill min and max timestamps in sb
struct p9_wstat and struct p9_stat_dotl indicate that the
wire transport uses u32 and u64 fields for timestamps.
Fill in the appropriate limits to avoid inconsistencies in
the vfs cached inode times when timestamps are outside the
permitted range.

Note that the upper bound for V9FS_PROTO_2000L is retained as S64_MAX.
This is because that is the upper bound supported by vfs.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Cc: ericvh@gmail.com
Cc: lucho@ionkov.net
Cc: asmadeus@codewreck.org
Cc: v9fs-developer@lists.sourceforge.net
2019-08-30 07:27:18 -07:00
Christoph Hellwig
f053cbd436 9p: pass the correct prototype to read_cache_page
Fix the callback 9p passes to read_cache_page to actually have the
proper type expected.  Casting around function pointers can easily
hide typing bugs, and defeats control flow protection.

Link: http://lkml.kernel.org/r/20190520055731.24538-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-12 11:05:43 -07:00
Thomas Gleixner
1f32761322 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 188
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 version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to free software
  foundation 51 franklin street fifth floor boston ma 02111 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 27 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.981318839@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:21 -07:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Al Viro
5e8a0770c0 9p: switch to ->free_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-01 22:43:23 -04:00
Linus Torvalds
db77bef53b Pull request for inlusion in 5.1
Two fixes (leak on invalid mount argument and possible deadlock on
 i_size update on 32bit smp) and a fall-through warning cleanup
 
 ----------------------------------------------------------------
 Gustavo A. R. Silva (1):
       9p: mark expected switch fall-through
 
 Hou Tao (1):
       9p: use inode->i_lock to protect i_size_write() under 32-bit
 
 zhengbin (1):
       9p/net: fix memory leak in p9_client_create
 
  fs/9p/v9fs_vfs.h       | 23 +++++++++++++++++++++--
  fs/9p/vfs_file.c       |  6 +++++-
  fs/9p/vfs_inode.c      | 23 +++++++++++------------
  fs/9p/vfs_inode_dotl.c | 27 ++++++++++++++-------------
  fs/9p/vfs_super.c      |  4 ++--
  net/9p/client.c        |  2 +-
  net/9p/trans_xen.c     |  2 +-
  7 files changed, 55 insertions(+), 32 deletions(-)
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAlyOVo4ACgkQq06b7GqY
 5nC7tQ//SJfSH6ooQE6nZywokUKpgXSzEPKHI6krI2lj8XuqL5r6iSQMqKwaWXFt
 h2onfPKtp+SHJaCnW82G9P54IvmiS9sMt6kRzGvFR0Gz93Cy4koIRc2TmAZLIw3N
 Gmyb7oEzUSmH8mJMt0qrlyxTzQEMhainWjod4QSmwuhJe9rndox+aBsNnFb7UOJw
 2bbV8T2j8amrF124VkK8wsglIpbKGJjDBAsfZ1ZHaWks2XqaNGDIvSIXse38WUhi
 rmOswBo1ZJBqS/FyojWW9hhtGmGSM9TgAzNdMABAZvjgmoWCk4xyO/6H95O8iL6Q
 Jp4XevUBcdwJWSp9VKeILLOyGx2UjkYy3KLuLnwyQUATDqDf+avdaiZC+Z0P/ulC
 l1fHgqK5E1wks328OvtO+kjFGqgiGzXfE1MnEmbFopvX3nqBr0yx8w4GdYm9irb9
 7PKz7HoGkOVuwhveNAQHR/Q58Mc/kxfOKvoRb19r5cM+pynFbWL9p4kFtG2Wc7sE
 y2xZ9jKKvoTh6BmAfkQTwJmGWDYWr3iSTq3YF5B7bNd8S9omzlY0e0PxOs0NHfMb
 wCoZhBRTAdv2NJvN2Q2nQeCFYPjCA7mnarDTVI3F+CwgGsbEFdCqi6B/H7aNcvv8
 uVm31guy2Df45ySL1FCz+sQdXIZBRS7+S38ufKXGlKERBIeEsCQ=
 =q3cR
 -----END PGP SIGNATURE-----

Merge tag '9p-for-5.1' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "Here is a 9p update for 5.1; there honestly hasn't been much.

  Two fixes (leak on invalid mount argument and possible deadlock on
  i_size update on 32bit smp) and a fall-through warning cleanup"

* tag '9p-for-5.1' of git://github.com/martinetd/linux:
  9p/net: fix memory leak in p9_client_create
  9p: use inode->i_lock to protect i_size_write() under 32-bit
  9p: mark expected switch fall-through
2019-03-17 09:10:56 -07:00
Nikolay Borisov
b5420237ec mm: refactor readahead defines in mm.h
All users of VM_MAX_READAHEAD actually convert it to kbytes and then to
pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This
simplifies the expression in every filesystem. Also rename the macro to
VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused
VM_MIN_READAHEAD

[akpm@linux-foundation.org: fix fs/io_uring.c, per Stephen]
Link: http://lkml.kernel.org/r/20181221144053.24318-1-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:01 -07:00
Hou Tao
5e3cc1ee14 9p: use inode->i_lock to protect i_size_write() under 32-bit
Use inode->i_lock to protect i_size_write(), else i_size_read() in
generic_fillattr() may loop infinitely in read_seqcount_begin() when
multiple processes invoke v9fs_vfs_getattr() or v9fs_vfs_getattr_dotl()
simultaneously under 32-bit SMP environment, and a soft lockup will be
triggered as show below:

  watchdog: BUG: soft lockup - CPU#5 stuck for 22s! [stat:2217]
  Modules linked in:
  CPU: 5 PID: 2217 Comm: stat Not tainted 5.0.0-rc1-00005-g7f702faf5a9e #4
  Hardware name: Generic DT based system
  PC is at generic_fillattr+0x104/0x108
  LR is at 0xec497f00
  pc : [<802b8898>]    lr : [<ec497f00>]    psr: 200c0013
  sp : ec497e20  ip : ed608030  fp : ec497e3c
  r10: 00000000  r9 : ec497f00  r8 : ed608030
  r7 : ec497ebc  r6 : ec497f00  r5 : ee5c1550  r4 : ee005780
  r3 : 0000052d  r2 : 00000000  r1 : ec497f00  r0 : ed608030
  Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
  Control: 10c5387d  Table: ac48006a  DAC: 00000051
  CPU: 5 PID: 2217 Comm: stat Not tainted 5.0.0-rc1-00005-g7f702faf5a9e #4
  Hardware name: Generic DT based system
  Backtrace:
  [<8010d974>] (dump_backtrace) from [<8010dc88>] (show_stack+0x20/0x24)
  [<8010dc68>] (show_stack) from [<80a1d194>] (dump_stack+0xb0/0xdc)
  [<80a1d0e4>] (dump_stack) from [<80109f34>] (show_regs+0x1c/0x20)
  [<80109f18>] (show_regs) from [<801d0a80>] (watchdog_timer_fn+0x280/0x2f8)
  [<801d0800>] (watchdog_timer_fn) from [<80198658>] (__hrtimer_run_queues+0x18c/0x380)
  [<801984cc>] (__hrtimer_run_queues) from [<80198e60>] (hrtimer_run_queues+0xb8/0xf0)
  [<80198da8>] (hrtimer_run_queues) from [<801973e8>] (run_local_timers+0x28/0x64)
  [<801973c0>] (run_local_timers) from [<80197460>] (update_process_times+0x3c/0x6c)
  [<80197424>] (update_process_times) from [<801ab2b8>] (tick_nohz_handler+0xe0/0x1bc)
  [<801ab1d8>] (tick_nohz_handler) from [<80843050>] (arch_timer_handler_virt+0x38/0x48)
  [<80843018>] (arch_timer_handler_virt) from [<80180a64>] (handle_percpu_devid_irq+0x8c/0x240)
  [<801809d8>] (handle_percpu_devid_irq) from [<8017ac20>] (generic_handle_irq+0x34/0x44)
  [<8017abec>] (generic_handle_irq) from [<8017b344>] (__handle_domain_irq+0x6c/0xc4)
  [<8017b2d8>] (__handle_domain_irq) from [<801022e0>] (gic_handle_irq+0x4c/0x88)
  [<80102294>] (gic_handle_irq) from [<80101a30>] (__irq_svc+0x70/0x98)
  [<802b8794>] (generic_fillattr) from [<8056b284>] (v9fs_vfs_getattr_dotl+0x74/0xa4)
  [<8056b210>] (v9fs_vfs_getattr_dotl) from [<802b8904>] (vfs_getattr_nosec+0x68/0x7c)
  [<802b889c>] (vfs_getattr_nosec) from [<802b895c>] (vfs_getattr+0x44/0x48)
  [<802b8918>] (vfs_getattr) from [<802b8a74>] (vfs_statx+0x9c/0xec)
  [<802b89d8>] (vfs_statx) from [<802b9428>] (sys_lstat64+0x48/0x78)
  [<802b93e0>] (sys_lstat64) from [<80101000>] (ret_fast_syscall+0x0/0x28)

[dominique.martinet@cea.fr: updated comment to not refer to a function
in another subsystem]
Link: http://lkml.kernel.org/r/20190124063514.8571-2-houtao1@huawei.com
Cc: stable@vger.kernel.org
Fixes: 7549ae3e81 ("9p: Use the i_size_[read, write]() macros instead of using inode->i_size directly.")
Reported-by: Xing Gaopeng <xingaopeng@huawei.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2019-03-03 14:04:07 +09:00
Linus Torvalds
9931a07d51 Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull AFS updates from Al Viro:
 "AFS series, with some iov_iter bits included"

* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  missing bits of "iov_iter: Separate type from direction and use accessor functions"
  afs: Probe multiple fileservers simultaneously
  afs: Fix callback handling
  afs: Eliminate the address pointer from the address list cursor
  afs: Allow dumping of server cursor on operation failure
  afs: Implement YFS support in the fs client
  afs: Expand data structure fields to support YFS
  afs: Get the target vnode in afs_rmdir() and get a callback on it
  afs: Calc callback expiry in op reply delivery
  afs: Fix FS.FetchStatus delivery from updating wrong vnode
  afs: Implement the YFS cache manager service
  afs: Remove callback details from afs_callback_break struct
  afs: Commit the status on a new file/dir/symlink
  afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
  afs: Don't invoke the server to read data beyond EOF
  afs: Add a couple of tracepoints to log I/O errors
  afs: Handle EIO from delivery function
  afs: Fix TTL on VL server and address lists
  afs: Implement VL server rotation
  afs: Improve FS server rotation error handling
  ...
2018-11-01 19:58:52 -07:00
David Howells
aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
Dominique Martinet
b4dc44b3ca 9p locks: fix glock.client_id leak in do_lock
the 9p client code overwrites our glock.client_id pointing to a static
buffer by an allocated string holding the network provided value which
we do not care about; free and reset the value as appropriate.

This is almost identical to the leak in v9fs_file_getlock() fixed by
Al Viro in commit ce85dd58ad ("9p: we are leaking glock.client_id
in v9fs_file_getlock()"), which was returned as an error by a coverity
false positive -- while we are here attempt to make the code slightly
more robust to future change of the net/9p/client code and hopefully
more clear to coverity that there is no problem.

Link: http://lkml.kernel.org/r/1536339057-21974-5-git-send-email-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-09-08 01:52:35 +09:00
Dominique Martinet
e02a53d92e 9p: acl: fix uninitialized iattr access
iattr is passed to v9fs_vfs_setattr_dotl which does send various
values from iattr over the wire, even if it tells the server to
only look at iattr.ia_valid fields this could leak some stack data.

Link: http://lkml.kernel.org/r/1536339057-21974-2-git-send-email-asmadeus@codewreck.org
Addresses-Coverity-ID: 1195601 ("Uninitalized scalar variable")
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-09-08 01:51:50 +09:00
Dinu-Razvan Chis-Serban
5e172f75e5 9p locks: add mount option for lock retry interval
The default P9_LOCK_TIMEOUT can be too long for some users exporting
a local file system to a guest VM (30s), make this configurable at
mount time.

Link: http://lkml.kernel.org/r/1536295827-3181-1-git-send-email-asmadeus@codewreck.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195727
Signed-off-by: Dinu-Razvan Chis-Serban <justcsdr@gmail.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-09-08 01:40:06 +09:00
Gertjan Halkes
2803cf4379 9p: do not trust pdu content for stat item size
v9fs_dir_readdir() could deadloop if a struct was sent with a size set
to -2

Link: http://lkml.kernel.org/r/1536134432-11997-1-git-send-email-asmadeus@codewreck.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88021
Signed-off-by: Gertjan Halkes <gertjan@google.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-09-08 01:40:06 +09:00
Gustavo A. R. Silva
426d5a0f97 9p: fix spelling mistake in fall-through annotation
Replace "fallthough" with a proper "fall through" annotation.

This fix is part of the ongoing efforts to enabling -Wimplicit-fallthrough

Link: http://lkml.kernel.org/r/20180903193806.GA11258@embeddedor.com
Addresses-Coverity-ID: 402012 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-09-08 01:39:47 +09:00
Dominique Martinet
81c99089bc v9fs_dir_readdir: fix double-free on p9stat_read error
p9stat_read will call p9stat_free on error, we should only free the
struct content on success.

There also is no need to "p9stat_init" st as the read function will
zero the whole struct for us anyway, so clean up the code a bit while
we are here.

Link: http://lkml.kernel.org/r/1535410108-20650-1-git-send-email-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Reported-by: syzbot+d4252148d198410b864f@syzkaller.appspotmail.com
2018-08-29 13:39:57 +09:00
Linus Torvalds
1f7a4c73a7 Pull request for inclusion in 4.19, take two
This tag is the same as 9p-for-4.19 without the two MAINTAINERS patches
 
 Contains mostly fixes (6 to be backported to stable) and a few changes,
 here is the breakdown:
  * Rework how fids are attributed by replacing some custom tracking in a
 list by an idr (f28cdf0430)
  * For packet-based transports (virtio/rdma) validate that the packet
 length matches what the header says (f984579a01)
  * A few race condition fixes found by syzkaller (9f476d7c54,
 430ac66eb4)
  * Missing argument check when NULL device is passed in sys_mount
 (10aa14527f)
  * A few virtio fixes (23cba9cbde, 31934da810, d28c756cae)
  * Some spelling and style fixes
 
 ----------------------------------------------------------------
 Chirantan Ekbote (1):
       9p/net: Fix zero-copy path in the 9p virtio transport
 
 Colin Ian King (1):
       fs/9p/v9fs.c: fix spelling mistake "Uknown" -> "Unknown"
 
 Jean-Philippe Brucker (1):
       net/9p: fix error path of p9_virtio_probe
 
 Matthew Wilcox (4):
       9p: Fix comment on smp_wmb
       9p: Change p9_fid_create calling convention
       9p: Replace the fidlist with an IDR
       9p: Embed wait_queue_head into p9_req_t
 
 Souptick Joarder (1):
       fs/9p/vfs_file.c: use new return type vm_fault_t
 
 Stephen Hemminger (1):
       9p: fix whitespace issues
 
 Tomas Bortoli (5):
       net/9p/client.c: version pointer uninitialized
       net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree()
       net/9p/trans_fd.c: fix race by holding the lock
       9p: validate PDU length
       9p: fix multiple NULL-pointer-dereferences
 
 jiangyiwen (2):
       net/9p/virtio: Fix hard lockup in req_done
       9p/virtio: fix off-by-one error in sg list bounds check
 
 piaojun (5):
       net/9p/client.c: add missing '\n' at the end of p9_debug()
       9p/net/protocol.c: return -ENOMEM when kmalloc() failed
       net/9p/trans_virtio.c: fix some spell mistakes in comments
       fs/9p/xattr.c: catch the error of p9_client_clunk when setting xattr failed
       net/9p/trans_virtio.c: add null terminal for mount tag
 
  fs/9p/v9fs.c            |   2 +-
  fs/9p/vfs_file.c        |   2 +-
  fs/9p/xattr.c           |   6 ++++--
  include/net/9p/client.h |  11 ++++-------
  net/9p/client.c         | 119 +++++++++++++++++++++++++++++++++++++++++++++++++-------------------------------------------------------------------
  net/9p/protocol.c       |   2 +-
  net/9p/trans_fd.c       |  22 +++++++++++++++-------
  net/9p/trans_rdma.c     |   4 ++++
  net/9p/trans_virtio.c   |  66 +++++++++++++++++++++++++++++++++++++---------------------------
  net/9p/trans_xen.c      |   3 +++
  net/9p/util.c           |   1 -
  12 files changed, 122 insertions(+), 116 deletions(-)
 -----BEGIN PGP SIGNATURE-----
 
 iF0EABECAB0WIQQ8idm2ZSicIMLgzKqoqIItDqvwPAUCW3ElNwAKCRCoqIItDqvw
 PMzfAKCkCYFyNC89vcpxcCNsK7rFQ1qKlwCgoaBpZDdegOu0jMB7cyKwAWrB0LM=
 =h3T0
 -----END PGP SIGNATURE-----

Merge tag '9p-for-4.19-2' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "This contains mostly fixes (6 to be backported to stable) and a few
  changes, here is the breakdown:

   - rework how fids are attributed by replacing some custom tracking in
     a list by an idr

   - for packet-based transports (virtio/rdma) validate that the packet
     length matches what the header says

   - a few race condition fixes found by syzkaller

   - missing argument check when NULL device is passed in sys_mount

   - a few virtio fixes

   - some spelling and style fixes"

* tag '9p-for-4.19-2' of git://github.com/martinetd/linux: (21 commits)
  net/9p/trans_virtio.c: add null terminal for mount tag
  9p/virtio: fix off-by-one error in sg list bounds check
  9p: fix whitespace issues
  9p: fix multiple NULL-pointer-dereferences
  fs/9p/xattr.c: catch the error of p9_client_clunk when setting xattr failed
  9p: validate PDU length
  net/9p/trans_fd.c: fix race by holding the lock
  net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree()
  net/9p/virtio: Fix hard lockup in req_done
  net/9p/trans_virtio.c: fix some spell mistakes in comments
  9p/net: Fix zero-copy path in the 9p virtio transport
  9p: Embed wait_queue_head into p9_req_t
  9p: Replace the fidlist with an IDR
  9p: Change p9_fid_create calling convention
  9p: Fix comment on smp_wmb
  net/9p/client.c: version pointer uninitialized
  fs/9p/v9fs.c: fix spelling mistake "Uknown" -> "Unknown"
  net/9p: fix error path of p9_virtio_probe
  9p/net/protocol.c: return -ENOMEM when kmalloc() failed
  net/9p/client.c: add missing '\n' at the end of p9_debug()
  ...
2018-08-17 17:27:58 -07:00
piaojun
3111784bee fs/9p/xattr.c: catch the error of p9_client_clunk when setting xattr failed
In my testing, v9fs_fid_xattr_set will return successfully even if the
backend ext4 filesystem has no space to store xattr key-value. That will
cause inconsistent behavior between front end and back end. The reason is
that lsetxattr will be triggered by p9_client_clunk, and unfortunately we
did not catch the error. This patch will catch the error to notify upper
caller.

p9_client_clunk (in 9p)
  p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
    v9fs_clunk (in qemu)
      put_fid
        free_fid
          v9fs_xattr_fid_clunk
            v9fs_co_lsetxattr
              s->ops->lsetxattr
                ext4_xattr_user_set (in host ext4 filesystem)

Link: http://lkml.kernel.org/r/5B57EACC.2060900@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:35:16 +09:00
Colin Ian King
6baaac0961 fs/9p/v9fs.c: fix spelling mistake "Uknown" -> "Unknown"
fix spelling mistake in pr_info message text

Link: http://lkml.kernel.org/r/20180526150650.10562-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Souptick Joarder
fe6340e2d1 fs/9p/vfs_file.c: use new return type vm_fault_t
Use new return type vm_fault_t for page_mkwrite handler.

See 1c8f422059 ("mm: change return type to vm_fault_t") for reference.

Link: http://lkml.kernel.org/r/20180702154928.GA3964@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jun Piao <piaojun@huawei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Al Viro
44907d7900 get rid of 'opened' argument of ->atomic_open() - part 3
now it can be done...

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12 10:04:20 -04:00
Al Viro
be12af3ef5 getting rid of 'opened' argument of ->atomic_open() - part 1
'opened' argument of finish_open() is unused.  Kill it.

Signed-off-by Al Viro <viro@zeniv.linux.org.uk>
2018-07-12 10:04:19 -04:00
Al Viro
73a09dd943 introduce FMODE_CREATED and switch to it
Parallel to FILE_CREATED, goes into ->f_mode instead of *opened.
NFS is a bit of a wart here - it doesn't have file at the point
where FILE_CREATED used to be set, so we need to propagate it
there (for now).  IMA is another one (here and everywhere)...

Note that this needs do_dentry_open() to leave old bits in ->f_mode
alone - we want it to preserve FMODE_CREATED if it had been already
set (no other bit can be there).

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12 10:04:18 -04:00
Kees Cook
6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Chengguang Xu
478ae0ca08 fs/9p: detect invalid options as much as possible
Currently when detecting invalid options in option parsing, some
options(e.g.  msize) just set errno and allow to continuously validate
other options so that it can detect invalid options as much as possible
and give proper error messages together.

This patch applies same rule to option 'cache' and 'access' when
detecting -EINVAL.

Link: http://lkml.kernel.org/r/1525340676-34072-2-git-send-email-cgxu519@gmx.com
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:34 -07:00
Al Viro
500e2ab6c3 9p: unify paths in v9fs_vfs_lookup()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-22 14:28:02 -04:00
Linus Torvalds
62f8e6c5dc fscache development
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAWsdxrvu3V2unywtrAQJVmQ/9Fv8d/Ecdwv5nxVBmN7uA8lOYcHEbZWmd
 FhFQE8qYLjKMo9Fy4tPkBbu1l6CVnetaTRE5qwixACJAftrdjABKJAazGR3Uxief
 0jMSWScrV1XCeRErPcczHcx52Hefl8f1DQdA3zpoF0ewz7CjyxMxkl67bsYJbNKE
 T4ebCu5IJk+5PPwwMM3REKjQbunSXXnzgCLUI2cc0Yf76CTVpx6p+NpxV+2wq0p7
 vym83F68qACAEzNH+oozN7IwqjkWyYOnTtCLiMsh4iq30jP6ohtLom6RcRp7QUxM
 Z9hxgG3NptypuVBO1jKxaQ6XZGgAasYmppOmJ/SoALv2PKsAbxi372lTR4ikceKq
 H4oNTbs5tVmyvu3qFwtLN+vX+GdfaoSUnUG8vTvnCB3tHHtYj7q5QeFE0HaX4QSq
 oLANkCOZU8TJsT30pxsCNYiqc5HK9kaLjUQId9K+xq7mM/IuhtNtBQ+ZpqAh5IxB
 4bXKYLdeJ1myZrkYTa6gcTqeFax3djCBJ3UvjTnuqRZAaQg079WkG84Kdq1ZjDRp
 IQpKQnPX9JGhjW1zqLK1Ay8h+HFPgWR5BBVOaLwImr1mH+ccG0iNIeDjrOc8h6J5
 e60XM/x2dIYxpXyFYAkldbAI24aRg1FNzfniG4rSAPecf3SwWrxg/qK7uujLbJHM
 fKNA80yifHo=
 =ukqs
 -----END PGP SIGNATURE-----

Merge tag 'fscache-next-20180406' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fscache updates from David Howells:
 "Three patches that fix some of AFS's usage of fscache:

   (1) Need to invalidate the cache if a foreign data change is detected
       on the server.

   (2) Move the vnode ID uniquifier (equivalent to i_generation) from
       the auxiliary data to the index key to prevent a race between
       file delete and a subsequent file create seeing the same index
       key.

   (3) Need to retire cookies that correspond to files that we think got
       deleted on the server.

  Four patches to fix some things in fscache and cachefiles:

   (4) Fix a couple of checker warnings.

   (5) Correctly indicate to the end-of-operation callback whether an
       operation completed or was cancelled.

   (6) Add a check for multiple cookie relinquishment.

   (7) Fix a path through the asynchronous write that doesn't wake up a
       waiter for a page if the cache decides not to write that page,
       but discards it instead.

  A couple of patches to add tracepoints to fscache and cachefiles:

   (8) Add tracepoints for cookie operators, object state machine
       execution, cachefiles object management and cachefiles VFS
       operations.

   (9) Add tracepoints for fscache operation management and page
       wrangling.

  And then three development patches:

  (10) Attach the index key and auxiliary data to the cookie, pass this
       information through various fscache-netfs API functions and get
       rid of the callbacks to the netfs to get it.

       This means that the cache can get at this information, even if
       the netfs goes away. It also means that the cache can be lazy in
       updating the coherency data.

  (11) Pass the object data size through various fscache-netfs API
       rather than calling back to the netfs for it, and store the value
       in the object.

       This makes it easier to correctly resize the object, as the size
       is updated on writes to the cache, rather than calling back out
       to the netfs.

  (12) Maintain a catalogue of allocated cookies. This makes it possible
       to catch cookie collision up front rather than down in the bowels
       of the cache being run from a service thread from the object
       state machine.

       This will also make it possible in the future to reconnect to a
       cookie that's not gone dead yet because it's waiting for
       finalisation of the storage and also make it possible to bring
       cookies online if the cache is added after the cookie has been
       obtained"

* tag 'fscache-next-20180406' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fscache: Maintain a catalogue of allocated cookies
  fscache: Pass object size in rather than calling back for it
  fscache: Attach the index key and aux data to the cookie
  fscache: Add more tracepoints
  fscache: Add tracepoints
  fscache: Fix hanging wait on page discarded by writeback
  fscache: Detect multiple relinquishment of a cookie
  fscache: Pass the correct cancelled indications to fscache_op_complete()
  fscache, cachefiles: Fix checker warnings
  afs: Be more aggressive in retiring cached vnodes
  afs: Use the vnode ID uniquifier in the cache key not the aux data
  afs: Invalidate cache on server data change
2018-04-07 09:08:24 -07:00
David Howells
ee1235a9a0 fscache: Pass object size in rather than calling back for it
Pass the object size in to fscache_acquire_cookie() and
fscache_write_page() rather than the netfs providing a callback by which it
can be received.  This makes it easier to update the size of the object
when a new page is written that extends the object.

The current object size is also passed by fscache to the check_aux
function, obviating the need to store it in the aux data.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
2018-04-06 14:05:14 +01:00
Yiwen Jiang
7ff3c20468 fs/9p: don't set SB_NOATIME by default
When the user uses some syscall, for example mmap(v9fs_file_mmap), it
will not update atime even if user's was set mnt_flags without
MNT_NOATIME, because v9fs defaults to settine SB_NOATIME in
v9fs_set_super.

For supporting access time updating when the user mounts with relatime,
we should not set SB_NOATIME by default.

Link: http://lkml.kernel.org/r/5AB9A377.6080906@huawei.com
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:22 -07:00
Chengguang Xu
a25c36577c 9p: check memory allocation result for cachetag
Check memory allocation result for cachetag in mount option parsing and
fix potential memory leak in the error case.

Link: http://lkml.kernel.org/r/1521614889-73446-1-git-send-email-cgxu519@gmx.com
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: <v9fs-developer@lists.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:22 -07:00
Eryu Guan
ac89b2ef9b 9p: don't maintain dir i_nlink if the exported fs doesn't either
If the exported filesystem dir on 9p server doesn't maintain accurate
i_nlink count, e.g.  always reports i_nlink as 1, then 9p should not
maintain nlink count either, otherwise drop_link would report warning
with i_nlink being zero.

For example:

 - overlayfs sets nlink to 1 for merged dir

 - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has
   more than EXT4_LINK_MAX (65000) links.

In this case, everytime a stat(2) call (getattr) on such exported dirs
on 9p client side, the i_nlink gets reset to 1, then operations like
rmdir(2), unlink(2) and rename(2) would cause the dir nlink to go to
zero (then negative), which results in warnings in drop_nlink() and/or
inc_nlink() calls.

This can be reproduced easily as the following steps:

 - export a merged overlayfs dir via qemu virtfs to guest

 - mount the exported virtfs in guest

 - create two sub-directories in the root dir of the mounted 9pfs

 - stat the root dir of 9pfs, this resets nlink to 1

 - remove all subdirs, the second unlink/rmdir would trigger warning

  ------------[ cut here ]------------
  WARNING: CPU: 3 PID: 1284 at fs/inode.c:282 drop_nlink+0x3e/0x50
  ...
  Call Trace:
    dump_stack+0x63/0x81
    __warn+0xcb/0xf0
    warn_slowpath_null+0x1d/0x20
    drop_nlink+0x3e/0x50
    v9fs_remove+0xaa/0x130 [9p]
    v9fs_vfs_rmdir+0x13/0x20 [9p]
    vfs_rmdir+0xb7/0x130
    do_rmdir+0x1b8/0x230
    SyS_unlinkat+0x22/0x30
    do_syscall_64+0x67/0x180
  ---[ end trace 43758d8ba91e603b ]---

Fix it by leaving i_nlink to be 1 and don't drop nlink if a directory
has nlink <= 2, which indicates that the underlying exported fs doesn't
maintain nlink count accurately.  This follows what ext4 does in
ext4_dec_count().

Link: http://lkml.kernel.org/r/20180312053829.4367-1-eguan@linux.alibaba.com
Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Tested-by: Roman Kapl <code@rkapl.cz>
Cc: Caspar Zhang <caspar@linux.alibaba.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: <v9fs-developer@lists.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:22 -07:00
David Howells
402cb8dda9 fscache: Attach the index key and aux data to the cookie
Attach copies of the index key and auxiliary data to the fscache cookie so
that:

 (1) The callbacks to the netfs for this stuff can be eliminated.  This
     can simplify things in the cache as the information is still
     available, even after the cache has relinquished the cookie.

 (2) Simplifies the locking requirements of accessing the information as we
     don't have to worry about the netfs object going away on us.

 (3) The cache can do lazy updating of the coherency information on disk.
     As long as the cache is flushed before reboot/poweroff, there's no
     need to update the coherency info on disk every time it changes.

 (4) Cookies can be hashed or put in a tree as the index key is easily
     available.  This allows:

     (a) Checks for duplicate cookies can be made at the top fscache layer
     	 rather than down in the bowels of the cache backend.

     (b) Caching can be added to a netfs object that has a cookie if the
     	 cache is brought online after the netfs object is allocated.

A certain amount of space is made in the cookie for inline copies of the
data, but if it won't fit there, extra memory will be allocated for it.

The downside of this is that live cache operation requires more memory.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
2018-04-04 13:41:28 +01:00
Adam Borowski
91581e4c60 fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at
This link is replicated in most filesystems' config stanzas.  Referring
to an archived version of that site is pointless as it mostly deals with
patches; user documentation is available elsewhere.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
CC: Alexander Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Steve French <smfrench@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-01-01 12:45:37 -07:00
Linus Torvalds
1751e8a6cb Rename superblock flags (MS_xyz -> SB_xyz)
This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.

Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.

The script to do this was:

    # places to look in; re security/*: it generally should *not* be
    # touched (that stuff parses mount(2) arguments directly), but
    # there are two places where we really deal with superblock flags.
    FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
            include/linux/fs.h include/uapi/linux/bfs_fs.h \
            security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
    # the list of MS_... constants
    SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
          DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
          POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
          I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
          ACTIVE NOUSER"

    SED_PROG=
    for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done

    # we want files that contain at least one of MS_...,
    # with fs/namespace.c and fs/pnode.c excluded.
    L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')

    for f in $L; do sed -i $f $SED_PROG; done

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-27 13:05:09 -08:00
Linus Torvalds
d18bee424b Merge branch '9p-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull 9p filesystemfixes from Al Viro:
 "Several 9p fixes"

* '9p-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  9p: Fix missing commas in mount options
  net/9p: Switch to wait_event_killable()
  fs/9p: Compare qid.path in v9fs_test_inode
2017-11-22 20:17:54 -10:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Tuomas Tynkkynen
8ee0316315 fs/9p: Compare qid.path in v9fs_test_inode
Commit fd2421f544 ("fs/9p: When doing inode lookup compare qid details
and inode mode bits.") transformed v9fs_qid_iget() to use iget5_locked()
instead of iget_locked(). However, the test() callback is not checking
fid.path at all, which means that a lookup in the inode cache can now
accidentally locate a completely wrong inode from the same inode hash
bucket if the other fields (qid.type and qid.version) match.

Fixes: fd2421f544 ("fs/9p: When doing inode lookup compare qid details and inode mode bits.")
Cc: stable@vger.kernel.org
Reviewed-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-23 23:10:01 -04:00
Alexander Levin
56ae414e9d 9p: set page uptodate when required in write_end()
Commit 77469c3f57 prevented setting the page as uptodate when we wrote
the right amount of data, fix that.

Fixes: 77469c3f57 ("9p: saner ->write_end() on failing copy into non-uptodate page")
Reviewed-by: Jan Kara <jack@suse.com>
Signed-off-by: Alexander Levin <alexander.levin@verizon.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-11 09:30:08 -07:00
Linus Torvalds
d34fc1adf0 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - various misc bits

 - DAX updates

 - OCFS2

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (119 commits)
  mm,fork: introduce MADV_WIPEONFORK
  x86,mpx: make mpx depend on x86-64 to free up VMA flag
  mm: add /proc/pid/smaps_rollup
  mm: hugetlb: clear target sub-page last when clearing huge page
  mm: oom: let oom_reap_task and exit_mmap run concurrently
  swap: choose swap device according to numa node
  mm: replace TIF_MEMDIE checks by tsk_is_oom_victim
  mm, oom: do not rely on TIF_MEMDIE for memory reserves access
  z3fold: use per-cpu unbuddied lists
  mm, swap: don't use VMA based swap readahead if HDD is used as swap
  mm, swap: add sysfs interface for VMA based swap readahead
  mm, swap: VMA based swap readahead
  mm, swap: fix swap readahead marking
  mm, swap: add swap readahead hit statistics
  mm/vmalloc.c: don't reinvent the wheel but use existing llist API
  mm/vmstat.c: fix wrong comment
  selftests/memfd: add memfd_create hugetlbfs selftest
  mm/shmem: add hugetlbfs support to memfd_create()
  mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups
  mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas()
  ...
2017-09-06 20:49:49 -07:00
Jan Kara
26b433d0da fscache: remove unused ->now_uncached callback
Patch series "Ranged pagevec lookup", v2.

In this series I make pagevec_lookup() update the index (to be
consistent with pagevec_lookup_tag() and also as a preparation for
ranged lookups), provide ranged variant of pagevec_lookup() and use it
in places where it makes sense.  This not only removes some common code
but is also a measurable performance win for some use cases (see patch
4/10) where radix tree is sparse and searching & grabing of a page after
the end of the range has measurable overhead.

This patch (of 10):

The callback doesn't ever get called.  Remove it.

Link: http://lkml.kernel.org/r/20170726114704.7626-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:26 -07:00
Linus Torvalds
ec3604c7a5 Writeback error handling fixes for v4.14
-----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZrTy3AAoJEAAOaEEZVoIVaucP/ApBAj2S5wzvlV1u6l8E6ae7
 ZeEEZfcWwzRYlKjZAkTWqj9XvGpDGO5gLq4wsZK2edFAq++/MJF8ZVtN4tdZ1kUZ
 DUvRodtVOrT08Kp9wZXGT7JOFrf6U/6gMcR6p0MuWnHndeKYvlpcFi9NPT4EC9/z
 Zm9V7gtlPdSOha7eaSjUS0+vLERkxqXLBW3Av9QUOBP/lbI3lqIroGKeHDYnVdya
 2P/k5EcRRJMyJP6TqyYxmmJl+UWjJFMLvnlUDBslHnD/u3mIUhw3JLHYBjn5dZRE
 Xjq56IDPoXDUvzlBhtn/Uqyx+/wtwsNsylpmKv6K5G1JfdeuSsPVsCey+A1cqV64
 LpE5896wf9TmnmI9LNyh6vDn925xPSGBiF45UEp5f9aO7jXeY0MaEZ8g+ENqFIDK
 v4gtZdS9FhYHV+/l4qEwYMKrqSbwKEs1r1FT+f4wnABby1ojfdA57ZPlp5PV2Vjp
 szTp88Zkb7cMvZwEnWwxWofcJNmgS7uNahvnQF3IJ4ITsioEkuyYR3K4ZQMaaaV9
 wCp6G0FhXZaK3OI7o9WiDwaO2elp9Hxc8bnqKpiBbHZkY0NLh7/++5VxpeNbTHFy
 AGijQiiKGNNyYqNj93wq9jpVdMNjB0pXrHRxfav8v7MtQ+WfbEoAENF4T7hN7iXn
 UuF6eSWEC5O1UCRUk1A+
 =LLY3
 -----END PGP SIGNATURE-----

Merge tag 'wberr-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull writeback error handling updates from Jeff Layton:
 "This pile continues the work from last cycle on better tracking
  writeback errors. In v4.13 we added some basic errseq_t infrastructure
  and converted a few filesystems to use it.

  This set continues refining that infrastructure, adds documentation,
  and converts most of the other filesystems to use it. The main
  exception at this point is the NFS client"

* tag 'wberr-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  ecryptfs: convert to file_write_and_wait in ->fsync
  mm: remove optimizations based on i_size in mapping writeback waits
  fs: convert a pile of fsync routines to errseq_t based reporting
  gfs2: convert to errseq_t based writeback error reporting for fsync
  fs: convert sync_file_range to use errseq_t based error-tracking
  mm: add file_fdatawait_range and file_write_and_wait
  fuse: convert to errseq_t based error tracking for fsync
  mm: consolidate dax / non-dax checks for writeback
  Documentation: add some docs for errseq_t
  errseq: rename __errseq_set to errseq_set
2017-09-06 14:11:03 -07:00
Jeff Layton
3b49c9a1e9 fs: convert a pile of fsync routines to errseq_t based reporting
This patch converts most of the in-kernel filesystems that do writeback
out of the pagecache to report errors using the errseq_t-based
infrastructure that was recently added. This allows them to report
errors once for each open file description.

Most filesystems have a fairly straightforward fsync operation. They
call filemap_write_and_wait_range to write back all of the data and
wait on it, and then (sometimes) sync out the metadata.

For those filesystems this is a straightforward conversion from calling
filemap_write_and_wait_range in their fsync operation to calling
file_write_and_wait_range.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-08-01 08:39:29 -04:00
Benjamin Coddington
9d5b86ac13 fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks
Since commit c69899a17c "NFSv4: Update of VFS byte range lock must be
atomic with the stateid update", NFSv4 has been inserting locks in rpciod
worker context.  The result is that the file_lock's fl_nspid is the
kworker's pid instead of the original userspace pid.

The fl_nspid is only used to represent the namespaced virtual pid number
when displaying locks or returning from F_GETLK.  There's no reason to set
it for every inserted lock, since we can usually just look it up from
fl_pid.  So, instead of looking up and holding struct pid for every lock,
let's just look up the virtual pid number from fl_pid when it is needed.
That means we can remove fl_nspid entirely.

The translaton and presentation of fl_pid should handle the following four
cases:

1 - F_GETLK on a remote file with a remote lock:
    In this case, the filesystem should determine the l_pid to return here.
    Filesystems should indicate that the fl_pid represents a non-local pid
    value that should not be translated by returning an fl_pid <= 0.

2 - F_GETLK on a local file with a remote lock:
    This should be the l_pid of the lock manager process, and translated.

3 - F_GETLK on a remote file with a local lock, and
4 - F_GETLK on a local file with a local lock:
    These should be the translated l_pid of the local locking process.

Fuse was already doing the correct thing by translating the pid into the
caller's namespace.  With this change we must update fuse to translate
to init's pid namespace, so that the locks API can then translate from
init's pid namespace into the pid namespace of the caller.

With this change, the locks API will expect that if a filesystem returns
a remote pid as opposed to a local pid for F_GETLK, that remote pid will
be <= 0.  This signifies that the pid is remote, and the locks API will
forego translating that pid into the pid namespace of the local calling
process.

Finally, we convert remote filesystems to present remote pids using
negative numbers. Have lustre, 9p, ceph, cifs, and dlm negate the remote
pid returned for F_GETLK lock requests.

Since local pids will never be larger than PID_MAX_LIMIT (which is
currently defined as <= 4 million), but pid_t is an unsigned int, we
should have plenty of room to represent remote pids with negative
numbers if we assume that remote pid numbers are similarly limited.

If this is not the case, then we run the risk of having a remote pid
returned for which there is also a corresponding local pid.  This is a
problem we have now, but this patch should reduce the chances of that
occurring, while also returning those remote pid numbers, for whatever
that may be worth.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-16 10:28:22 -04:00
David Howells
c4fac91004 9p: Implement show_options
Implement the show_options superblock op for 9p as part of a bid to get
rid of s_options and generic_show_options() to make it easier to implement
a context-based mount where the mount options can be passed individually
over a file descriptor.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric Van Hensbergen <ericvh@gmail.com>
cc: Ron Minnich <rminnich@sandia.gov>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: v9fs-developer@lists.sourceforge.net
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-07-11 06:08:58 -04:00
Jan Kara
71304feba3 9p: Convert to separately allocated bdi
Allocate struct backing_dev_info separately instead of embedding it
inside session. This unifies handling of bdi among users.

CC: Eric Van Hensbergen <ericvh@gmail.com>
CC: Ron Minnich <rminnich@sandia.gov>
CC: Latchesar Ionkov <lucho@ionkov.net>
CC: v9fs-developer@lists.sourceforge.net
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:09:55 -06:00
Linus Torvalds
0710f3ff91 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc final vfs updates from Al Viro:
 "A few unrelated patches that got beating in -next.

  Everything else will have to go into the next window ;-/"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  hfs: fix hfs_readdir()
  selftest for default_file_splice_read() infoleak
  9p: constify ->d_name handling
2017-03-03 21:44:35 -08:00
Linus Torvalds
590dce2d49 Merge branch 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs 'statx()' update from Al Viro.

This adds the new extended stat() interface that internally subsumes our
previous stat interfaces, and allows user mode to specify in more detail
what kind of information it wants.

It also allows for some explicit synchronization information to be
passed to the filesystem, which can be relevant for network filesystems:
is the cached value ok, or do you need open/close consistency, or what?

From David Howells.

Andreas Dilger points out that the first version of the extended statx
interface was posted June 29, 2010:

    https://www.spinics.net/lists/linux-fsdevel/msg33831.html

* 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  statx: Add a system call to make enhanced file info available
2017-03-03 11:38:56 -08:00
David Howells
a528d35e8b statx: Add a system call to make enhanced file info available
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.

The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode.  This change is propagated to the vfs_getattr*()
function.

Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.

========
OVERVIEW
========

The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.

A number of requests were gathered for features to be included.  The
following have been included:

 (1) Make the fields a consistent size on all arches and make them large.

 (2) Spare space, request flags and information flags are provided for
     future expansion.

 (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
     __s64).

 (4) Creation time: The SMB protocol carries the creation time, which could
     be exported by Samba, which will in turn help CIFS make use of
     FS-Cache as that can be used for coherency data (stx_btime).

     This is also specified in NFSv4 as a recommended attribute and could
     be exported by NFSD [Steve French].

 (5) Lightweight stat: Ask for just those details of interest, and allow a
     netfs (such as NFS) to approximate anything not of interest, possibly
     without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
     Dilger] (AT_STATX_DONT_SYNC).

 (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
     its cached attributes are up to date [Trond Myklebust]
     (AT_STATX_FORCE_SYNC).

And the following have been left out for future extension:

 (7) Data version number: Could be used by userspace NFS servers [Aneesh
     Kumar].

     Can also be used to modify fill_post_wcc() in NFSD which retrieves
     i_version directly, but has just called vfs_getattr().  It could get
     it from the kstat struct if it used vfs_xgetattr() instead.

     (There's disagreement on the exact semantics of a single field, since
     not all filesystems do this the same way).

 (8) BSD stat compatibility: Including more fields from the BSD stat such
     as creation time (st_btime) and inode generation number (st_gen)
     [Jeremy Allison, Bernd Schubert].

 (9) Inode generation number: Useful for FUSE and userspace NFS servers
     [Bernd Schubert].

     (This was asked for but later deemed unnecessary with the
     open-by-handle capability available and caused disagreement as to
     whether it's a security hole or not).

(10) Extra coherency data may be useful in making backups [Andreas Dilger].

     (No particular data were offered, but things like last backup
     timestamp, the data version number and the DOS archive bit would come
     into this category).

(11) Allow the filesystem to indicate what it can/cannot provide: A
     filesystem can now say it doesn't support a standard stat feature if
     that isn't available, so if, for instance, inode numbers or UIDs don't
     exist or are fabricated locally...

     (This requires a separate system call - I have an fsinfo() call idea
     for this).

(12) Store a 16-byte volume ID in the superblock that can be returned in
     struct xstat [Steve French].

     (Deferred to fsinfo).

(13) Include granularity fields in the time data to indicate the
     granularity of each of the times (NFSv4 time_delta) [Steve French].

     (Deferred to fsinfo).

(14) FS_IOC_GETFLAGS value.  These could be translated to BSD's st_flags.
     Note that the Linux IOC flags are a mess and filesystems such as Ext4
     define flags that aren't in linux/fs.h, so translation in the kernel
     may be a necessity (or, possibly, we provide the filesystem type too).

     (Some attributes are made available in stx_attributes, but the general
     feeling was that the IOC flags were to ext[234]-specific and shouldn't
     be exposed through statx this way).

(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
     Michael Kerrisk].

     (Deferred, probably to fsinfo.  Finding out if there's an ACL or
     seclabal might require extra filesystem operations).

(16) Femtosecond-resolution timestamps [Dave Chinner].

     (A __reserved field has been left in the statx_timestamp struct for
     this - if there proves to be a need).

(17) A set multiple attributes syscall to go with this.

===============
NEW SYSTEM CALL
===============

The new system call is:

	int ret = statx(int dfd,
			const char *filename,
			unsigned int flags,
			unsigned int mask,
			struct statx *buffer);

The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat().  There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags.  There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.

Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):

 (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
     respect.

 (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
     its attributes with the server - which might require data writeback to
     occur to get the timestamps correct.

 (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
     network filesystem.  The resulting values should be considered
     approximate.

mask is a bitmask indicating the fields in struct statx that are of
interest to the caller.  The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat().  It should be noted that asking for
more information may entail extra I/O operations.

buffer points to the destination for the data.  This must be 256 bytes in
size.

======================
MAIN ATTRIBUTES RECORD
======================

The following structures are defined in which to return the main attribute
set:

	struct statx_timestamp {
		__s64	tv_sec;
		__s32	tv_nsec;
		__s32	__reserved;
	};

	struct statx {
		__u32	stx_mask;
		__u32	stx_blksize;
		__u64	stx_attributes;
		__u32	stx_nlink;
		__u32	stx_uid;
		__u32	stx_gid;
		__u16	stx_mode;
		__u16	__spare0[1];
		__u64	stx_ino;
		__u64	stx_size;
		__u64	stx_blocks;
		__u64	__spare1[1];
		struct statx_timestamp	stx_atime;
		struct statx_timestamp	stx_btime;
		struct statx_timestamp	stx_ctime;
		struct statx_timestamp	stx_mtime;
		__u32	stx_rdev_major;
		__u32	stx_rdev_minor;
		__u32	stx_dev_major;
		__u32	stx_dev_minor;
		__u64	__spare2[14];
	};

The defined bits in request_mask and stx_mask are:

	STATX_TYPE		Want/got stx_mode & S_IFMT
	STATX_MODE		Want/got stx_mode & ~S_IFMT
	STATX_NLINK		Want/got stx_nlink
	STATX_UID		Want/got stx_uid
	STATX_GID		Want/got stx_gid
	STATX_ATIME		Want/got stx_atime{,_ns}
	STATX_MTIME		Want/got stx_mtime{,_ns}
	STATX_CTIME		Want/got stx_ctime{,_ns}
	STATX_INO		Want/got stx_ino
	STATX_SIZE		Want/got stx_size
	STATX_BLOCKS		Want/got stx_blocks
	STATX_BASIC_STATS	[The stuff in the normal stat struct]
	STATX_BTIME		Want/got stx_btime{,_ns}
	STATX_ALL		[All currently available stuff]

stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.

Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution.  Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.

The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does.  The following
attributes map to FS_*_FL flags and are the same numerical value:

	STATX_ATTR_COMPRESSED		File is compressed by the fs
	STATX_ATTR_IMMUTABLE		File is marked immutable
	STATX_ATTR_APPEND		File is append-only
	STATX_ATTR_NODUMP		File is not to be dumped
	STATX_ATTR_ENCRYPTED		File requires key to decrypt in fs

Within the kernel, the supported flags are listed by:

	KSTAT_ATTR_FS_IOC_FLAGS

[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]

New flags include:

	STATX_ATTR_AUTOMOUNT		Object is an automount trigger

These are for the use of GUI tools that might want to mark files specially,
depending on what they are.

Fields in struct statx come in a number of classes:

 (0) stx_dev_*, stx_blksize.

     These are local system information and are always available.

 (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
     stx_size, stx_blocks.

     These will be returned whether the caller asks for them or not.  The
     corresponding bits in stx_mask will be set to indicate whether they
     actually have valid values.

     If the caller didn't ask for them, then they may be approximated.  For
     example, NFS won't waste any time updating them from the server,
     unless as a byproduct of updating something requested.

     If the values don't actually exist for the underlying object (such as
     UID or GID on a DOS file), then the bit won't be set in the stx_mask,
     even if the caller asked for the value.  In such a case, the returned
     value will be a fabrication.

     Note that there are instances where the type might not be valid, for
     instance Windows reparse points.

 (2) stx_rdev_*.

     This will be set only if stx_mode indicates we're looking at a
     blockdev or a chardev, otherwise will be 0.

 (3) stx_btime.

     Similar to (1), except this will be set to 0 if it doesn't exist.

=======
TESTING
=======

The following test program can be used to test the statx system call:

	samples/statx/test-statx.c

Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.

Here's some example output.  Firstly, an NFS directory that crosses to
another FSID.  Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.

	[root@andromeda ~]# /tmp/test-statx -A /warthog/data
	statx(/warthog/data) = 0
	results=7ff
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:26           Inode: 1703937     Links: 125
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2016-11-24 09:02:12.219699527+0000
	Modify: 2016-11-17 10:44:36.225653653+0000
	Change: 2016-11-17 10:44:36.225653653+0000
	Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)

Secondly, the result of automounting on that directory.

	[root@andromeda ~]# /tmp/test-statx /warthog/data
	statx(/warthog/data) = 0
	results=7ff
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:27           Inode: 2           Links: 125
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2016-11-24 09:02:12.219699527+0000
	Modify: 2016-11-17 10:44:36.225653653+0000
	Change: 2016-11-17 10:44:36.225653653+0000

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-02 20:51:15 -05:00
Ingo Molnar
5b825c3af1 sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.

Note that even if the count where we need to add extra headers seems high,
it's still a net win, because <linux/sched.h> is included in over
2,200 files ...

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:31 +01:00