1
Commit Graph

151 Commits

Author SHA1 Message Date
Dominique Martinet
be2ca38253 Revert "fs/9p: simplify iget to remove unnecessary paths"
This reverts commit 724a08450f.

This code simplification introduced significant regressions on servers
that do not remap inode numbers when exporting multiple underlying
filesystems with colliding inodes, as can be illustrated with simple
tmpfs exports in qemu with remapping disabled:
```
# host side
cd /tmp/linux-test
mkdir m1 m2
mount -t tmpfs tmpfs m1
mount -t tmpfs tmpfs m2
mkdir m1/dir m2/dir
echo foo > m1/dir/foo
echo bar > m2/dir/bar

# guest side
# started with -virtfs local,path=/tmp/linux-test,mount_tag=tmp,security_model=mapped-file
mount -t 9p -o trans=virtio,debug=1 tmp /mnt/t

ls /mnt/t/m1/dir
# foo
ls /mnt/t/m2/dir
# bar (works ok if directry isn't open)

# cd to keep first dir's inode alive
cd /mnt/t/m1/dir
ls /mnt/t/m2/dir
# foo (should be bar)
```
Other examples can be crafted with regular files with fscache enabled,
in which case I/Os just happen to the wrong file leading to
corruptions, or guest failing to boot with:
  | VFS: Lookup of 'com.android.runtime' in 9p 9p would have caused loop

In theory, we'd want the servers to be smart enough and ensure they
never send us two different files with the same 'qid.path', but while
qemu has an option to remap that is recommended (and qemu prints a
warning if this case happens), there are many other servers which do
not (kvmtool, nfs-ganesha, probably diod...), we should at least ensure
we don't cause regressions on this:
- assume servers can't be trusted and operations that should get a 'new'
inode properly do so. commit d05dcfdf5e (" fs/9p: mitigate inode
collisions") attempted to do this, but v9fs_fid_iget_dotl() was not
called so some higher level of caching got in the way; this needs to be
fixed properly before we can re-apply the patches.
- if we ever want to really simplify this code, we will need to add some
negotiation with the server at mount time where the server could claim
they handle this properly, at which point we could optimize this out.
(but that might not be needed at all if we properly handle the 'new'
check?)

Fixes: 724a08450f ("fs/9p: simplify iget to remove unnecessary paths")
Reported-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/all/20240408141436.GA17022@redhat.com/
Link: https://lkml.kernel.org/r/20240923100508.GA32066@willie-the-truck
Cc: stable@vger.kernel.org # v6.9+
Message-ID: <20241024-revert_iget-v1-4-4cac63d25f72@codewreck.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2024-10-25 06:26:09 +09:00
Dominique Martinet
26f8dd2dde Revert "fs/9p: fix uaf in in v9fs_stat2inode_dotl"
This reverts commit 11763a8598.

This is a requirement to revert commit 724a08450f ("fs/9p: simplify
iget to remove unnecessary paths"), see that revert for details.

Fixes: 724a08450f ("fs/9p: simplify iget to remove unnecessary paths")
Reported-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20240923100508.GA32066@willie-the-truck
Cc: stable@vger.kernel.org # v6.9+
Message-ID: <20241024-revert_iget-v1-3-4cac63d25f72@codewreck.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2024-10-25 06:26:09 +09:00
Dominique Martinet
fedd06210b Revert "fs/9p: remove redundant pointer v9ses"
This reverts commit 10211b4a23.

This is a requirement to revert commit 724a08450f ("fs/9p: simplify
iget to remove unnecessary paths"), see that revert for details.

Fixes: 724a08450f ("fs/9p: simplify iget to remove unnecessary paths")
Reported-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20240923100508.GA32066@willie-the-truck
Cc: stable@vger.kernel.org # v6.9+
Message-ID: <20241024-revert_iget-v1-2-4cac63d25f72@codewreck.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2024-10-25 06:26:09 +09:00
Dominique Martinet
f69999b5f9 Revert " fs/9p: mitigate inode collisions"
This reverts commit d05dcfdf5e.

This is a requirement to revert commit 724a08450f ("fs/9p: simplify
iget to remove unnecessary paths"), see that revert for details.

Fixes: 724a08450f ("fs/9p: simplify iget to remove unnecessary paths")
Reported-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20240923100508.GA32066@willie-the-truck
Cc: stable@vger.kernel.org # v6.9+
Message-ID: <20241024-revert_iget-v1-1-4cac63d25f72@codewreck.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2024-10-25 06:26:08 +09:00
Eric Van Hensbergen
d05dcfdf5e
fs/9p: mitigate inode collisions
Detect and mitigate inode collsions that now occur since we
fixed 9p generating duplicate inode structures.  Underlying
cause of these appears to be a race condition between reuse
of inode numbers in underlying file system and cleanup of
inode numbers in the client.  Enabling caching
makes this much more likely to happen as it increases cleanup
latency due to writebacks.

Reported-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-04-22 15:34:27 +00:00
Colin Ian King
10211b4a23
fs/9p: remove redundant pointer v9ses
Pointer v9ses is being assigned the value from the return of inlined
function v9fs_inode2v9ses (which just returns inode->i_sb->s_fs_info).
The pointer is not used after the assignment, so the variable is
redundant and can be removed.

Cleans up clang scan warnings such as:
fs/9p/vfs_inode_dotl.c:300:28: warning: variable 'v9ses' set but not
used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-03-25 00:34:35 +00:00
Lizhi Xu
11763a8598
fs/9p: fix uaf in in v9fs_stat2inode_dotl
The incorrect logical order of accessing the st object code in v9fs_fid_iget_dotl
is causing this uaf.

Fixes: 724a08450f ("fs/9p: simplify iget to remove unnecessary paths")
Reported-and-tested-by: syzbot+7a3d75905ea1a830dbe5@syzkaller.appspotmail.com
Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>
Tested-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-03-25 00:34:35 +00:00
Eric Van Hensbergen
724a08450f
fs/9p: simplify iget to remove unnecessary paths
Remove the additional comparison operators and switch to
simply lookup by inode number (aka qid.path).

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-01-26 16:46:56 +00:00
Eric Van Hensbergen
b91a26696e
fs/9p: rework qid2ino logic
This changes from a function to a macro because we can
figure out if we are 32 or 64 bit at compile time.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-01-26 16:46:56 +00:00
Eric Van Hensbergen
2dc92e5975
fs/9p: Eliminate redundant non-cache path in mknod
Like symlink, mknod had a seperate path with different inode
allocation -- but this seems unnecessary, so eliminating this path.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-01-26 16:46:56 +00:00
Eric Van Hensbergen
6bb2932722
fs/9p: remove walk and inode allocation from symlink
Symlink had a bunch of extra operations which essentially
end up discarded.  It was walking the fid to the new file and
creating an inode for it, but those semantics are part of
tsymlink.  This did prepopulate the cache, but that also seems
potentially unnecessary and frought with peril.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-01-26 16:46:55 +00:00
Eric Van Hensbergen
44c53ac097
fs/9p: convert mkdir to use get_new_inode
mkdir had different code paths for inode creation, cache used
the get_new_inode_from_fid helper, but non-cached used
v9fs_get_inode.  Collapsed into a single implementation across
both as there should be no difference.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-01-26 16:46:55 +00:00
David Howells
9546ac78b2 9p: Fix initialisation of netfs_inode for 9p
The 9p filesystem is calling netfs_inode_init() in v9fs_init_inode() -
before the struct inode fields have been initialised from the obtained file
stats (ie. after v9fs_stat2inode*() has been called), but netfslib wants to
set a couple of its fields from i_size.

Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Dominique Martinet <asmadeus@codewreck.org>
Acked-by: Dominique Martinet <asmadeus@codewreck.org>
cc: Eric Van Hensbergen <ericvh@kernel.org>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Christian Schoenebeck <linux_oss@crudebyte.com>
cc: v9fs@lists.linux.dev
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
2024-01-03 14:53:01 +00:00
David Howells
80105ed2fd 9p: Use netfslib read/write_iter
Use netfslib's read and write iteration helpers, allowing netfslib to take
over the management of the page cache for 9p files and to manage local disk
caching.  In particular, this eliminates write_begin, write_end, writepage
and all mentions of struct page and struct folio from 9p.

Note that netfslib now offers the possibility of write-through caching if
that is desirable for 9p: just set the NETFS_ICTX_WRITETHROUGH flag in
v9inode->netfs.flags in v9fs_set_netfs_context().

Note also this is untested as I can't get ganesha.nfsd to correctly parse
the config to turn on 9p support.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Eric Van Hensbergen <ericvh@kernel.org>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Christian Schoenebeck <linux_oss@crudebyte.com>
cc: v9fs@lists.linux.dev
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
2023-12-28 09:45:28 +00:00
Jeff Layton
d0242a3a61
9p: convert to new timestamp accessors
Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-13-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-18 13:26:17 +02:00
Linus Torvalds
615e95831e v6.6-vfs.ctime
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZOXTKAAKCRCRxhvAZXjc
 oifJAQCzi/p+AdQu8LA/0XvR7fTwaq64ZDCibU4BISuLGT2kEgEAuGbuoFZa0rs2
 XYD/s4+gi64p9Z01MmXm2XO1pu3GPg0=
 =eJz5
 -----END PGP SIGNATURE-----

Merge tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs timestamp updates from Christian Brauner:
 "This adds VFS support for multi-grain timestamps and converts tmpfs,
  xfs, ext4, and btrfs to use them. This carries acks from all relevant
  filesystems.

  The VFS always uses coarse-grained timestamps when updating the ctime
  and mtime after a change. This has the benefit of allowing filesystems
  to optimize away a lot of metadata updates, down to around 1 per
  jiffy, even when a file is under heavy writes.

  Unfortunately, this has always been an issue when we're exporting via
  NFSv3, which relies on timestamps to validate caches. A lot of changes
  can happen in a jiffy, so timestamps aren't sufficient to help the
  client decide to invalidate the cache.

  Even with NFSv4, a lot of exported filesystems don't properly support
  a change attribute and are subject to the same problems with timestamp
  granularity. Other applications have similar issues with timestamps
  (e.g., backup applications).

  If we were to always use fine-grained timestamps, that would improve
  the situation, but that becomes rather expensive, as the underlying
  filesystem would have to log a lot more metadata updates.

  This introduces fine-grained timestamps that are used when they are
  actively queried.

  This uses the 31st bit of the ctime tv_nsec field to indicate that
  something has queried the inode for the mtime or ctime. When this flag
  is set, on the next mtime or ctime update, the kernel will fetch a
  fine-grained timestamp instead of the usual coarse-grained one.

  As POSIX generally mandates that when the mtime changes, the ctime
  must also change the kernel always stores normalized ctime values, so
  only the first 30 bits of the tv_nsec field are ever used.

  Filesytems can opt into this behavior by setting the FS_MGTIME flag in
  the fstype. Filesystems that don't set this flag will continue to use
  coarse-grained timestamps.

  Various preparatory changes, fixes and cleanups are included:

   - Fixup all relevant places where POSIX requires updating ctime
     together with mtime. This is a wide-range of places and all
     maintainers provided necessary Acks.

   - Add new accessors for inode->i_ctime directly and change all
     callers to rely on them. Plain accesses to inode->i_ctime are now
     gone and it is accordingly rename to inode->__i_ctime and commented
     as requiring accessors.

   - Extend generic_fillattr() to pass in a request mask mirroring in a
     sense the statx() uapi. This allows callers to pass in a request
     mask to only get a subset of attributes filled in.

   - Rework timestamp updates so it's possible to drop the @now
     parameter the update_time() inode operation and associated helpers.

   - Add inode_update_timestamps() and convert all filesystems to it
     removing a bunch of open-coding"

* tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (107 commits)
  btrfs: convert to multigrain timestamps
  ext4: switch to multigrain timestamps
  xfs: switch to multigrain timestamps
  tmpfs: add support for multigrain timestamps
  fs: add infrastructure for multigrain timestamps
  fs: drop the timespec64 argument from update_time
  xfs: have xfs_vn_update_time gets its own timestamp
  fat: make fat_update_time get its own timestamp
  fat: remove i_version handling from fat_update_time
  ubifs: have ubifs_update_time use inode_update_timestamps
  btrfs: have it use inode_update_timestamps
  fs: drop the timespec64 arg from generic_update_time
  fs: pass the request_mask to generic_fillattr
  fs: remove silly warning from current_time
  gfs2: fix timestamp handling on quota inodes
  fs: rename i_ctime field to __i_ctime
  selinux: convert to ctime accessor functions
  security: convert to ctime accessor functions
  apparmor: convert to ctime accessor functions
  sunrpc: convert to ctime accessor functions
  ...
2023-08-28 09:31:32 -07:00
Jeff Layton
0d72b92883 fs: pass the request_mask to generic_fillattr
generic_fillattr just fills in the entire stat struct indiscriminately
today, copying data from the inode. There is at least one attribute
(STATX_CHANGE_COOKIE) that can have side effects when it is reported,
and we're looking at adding more with the addition of multigrain
timestamps.

Add a request_mask argument to generic_fillattr and have most callers
just pass in the value that is passed to getattr. Have other callers
(e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of
STATX_CHANGE_COOKIE into generic_fillattr.

Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Paulo Alcantara (SUSE)" <pc@manguebit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230807-mgctime-v7-2-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-08-09 08:56:36 +02:00
Dominique Martinet
cf7c33d332
9p: remove dead stores (variable set again without being read)
The 9p code for some reason used to initialize variables outside of the
declaration, e.g. instead of just initializing the variable like this:

int retval = 0

We would be doing this:

int retval;
retval = 0;

This is perfectly fine and the compiler will just optimize dead stores
anyway, but scan-build seems to think this is a problem and there are
many of these warnings making the output of scan-build full of such
warnings:
fs/9p/vfs_inode.c:916:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores]
        retval = 0;
        ^        ~

I have no strong opinion here, but if we want to regularly run
scan-build we should fix these just to silence the messages.

I've confirmed these all are indeed ok to remove.

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2023-07-20 19:14:50 +00:00
Jeff Layton
4f87180060 9p: convert to ctime accessor functions
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-19-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-13 10:28:03 +02:00
Linus Torvalds
ed23734c23 Including fixes from netfilter.
Current release - regressions:
 
  - sched: act_pedit: free pedit keys on bail from offset check
 
 Current release - new code bugs:
 
  - pds_core:
   - Kconfig fixes (DEBUGFS and AUXILIARY_BUS)
   - fix mutex double unlock in error path
 
 Previous releases - regressions:
 
  - sched: cls_api: remove block_cb from driver_list before freeing
 
  - nf_tables: fix ct untracked match breakage
 
  - eth: mtk_eth_soc: drop generic vlan rx offload
 
  - sched: flower: fix error handler on replace
 
 Previous releases - always broken:
 
  - tcp: fix skb_copy_ubufs() vs BIG TCP
 
  - ipv6: fix skb hash for some RST packets
 
  - af_packet: don't send zero-byte data in packet_sendmsg_spkt()
 
  - rxrpc: timeout handling fixes after moving client call connection
    to the I/O thread
 
  - ixgbe: fix panic during XDP_TX with > 64 CPUs
 
  - igc: RMW the SRRCTL register to prevent losing timestamp config
 
  - dsa: mt7530: fix corrupt frames using TRGMII on 40 MHz XTAL MT7621
 
  - r8152:
    - fix flow control issue of RTL8156A
    - fix the poor throughput for 2.5G devices
    - move setting r8153b_rx_agg_chg_indicate() to fix coalescing
    - enable autosuspend
 
  - ncsi: clear Tx enable mode when handling a Config required AEN
 
  - octeontx2-pf: macsec: fixes for CN10KB ASIC rev
 
 Misc:
 
  - 9p: remove INET dependency
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE6jPA+I1ugmIBA4hXMUZtbf5SIrsFAmRVeUIACgkQMUZtbf5S
 IrtTug/9Hhg/L0PTSwrfuGh4W1/cjheMWppNLkwyWQUiKG7FcZQ9vu9PxceE3VRu
 2fTqHyvgDMZ8jACovXObeda8z1+g3s/tIPaXELephBIjVlF/h3kG2OaIzlU4jDb4
 A4vklwf8eLbfyVBG22QgKl/I70zVMtnmnOo6c6CPuIOTcMPzslndFO9tB0nCg99F
 DCgCM1BBP1tz+OUch2rLnSzYcqkWqS49BhRk6dhYSliawUFU/5+1tDGDjwWolkfm
 0jqP9DjBOSpZKO8m7SpsUNz7NFRIfYErWZ+YebWbggNxj/6TRJTP83MM0tGoK1rE
 /mz2xpuOki59frlwVOAD6gb/qefjHUp21P4NA7bnhizxFlQL5MHpCeGQ9yLHBSmY
 9Q4ArJkM4jXQ0oDA2nII/pz+cDZGEWFGQ14WW3kYUb7WFmISH4I9OiA9i0TBW6OL
 r1Y/rqzkUvtKWzh9RpiAF9lsdHAm3SX9ES5RfMxzv0x886VOZR4jaMmokRDdPRzq
 0r2Oyj75b62+X0r44Fe22Pl/kPS/uh3642xo9h85aAv/EvhT9JNzMvomJm9d6tkb
 966I085AVbwxPAy+rl5SWyAq60EWDExNTjZvPv0mSMlmSsQ9iK5//xOF2Saw2zai
 /44zQ27tVGkCC44Ou5KmfJN3u4OrKkhcuyxtcDr9QeoOdKZRkMg=
 =9xND
 -----END PGP SIGNATURE-----

Merge tag 'net-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from netfilter.

  Current release - regressions:

   - sched: act_pedit: free pedit keys on bail from offset check

  Current release - new code bugs:

   - pds_core:
      - Kconfig fixes (DEBUGFS and AUXILIARY_BUS)
      - fix mutex double unlock in error path

  Previous releases - regressions:

   - sched: cls_api: remove block_cb from driver_list before freeing

   - nf_tables: fix ct untracked match breakage

   - eth: mtk_eth_soc: drop generic vlan rx offload

   - sched: flower: fix error handler on replace

  Previous releases - always broken:

   - tcp: fix skb_copy_ubufs() vs BIG TCP

   - ipv6: fix skb hash for some RST packets

   - af_packet: don't send zero-byte data in packet_sendmsg_spkt()

   - rxrpc: timeout handling fixes after moving client call connection
     to the I/O thread

   - ixgbe: fix panic during XDP_TX with > 64 CPUs

   - igc: RMW the SRRCTL register to prevent losing timestamp config

   - dsa: mt7530: fix corrupt frames using TRGMII on 40 MHz XTAL MT7621

   - r8152:
      - fix flow control issue of RTL8156A
      - fix the poor throughput for 2.5G devices
      - move setting r8153b_rx_agg_chg_indicate() to fix coalescing
      - enable autosuspend

   - ncsi: clear Tx enable mode when handling a Config required AEN

   - octeontx2-pf: macsec: fixes for CN10KB ASIC rev

  Misc:

   - 9p: remove INET dependency"

* tag 'net-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits)
  net: bcmgenet: Remove phy_stop() from bcmgenet_netif_stop()
  pds_core: fix mutex double unlock in error path
  net/sched: flower: fix error handler on replace
  Revert "net/sched: flower: Fix wrong handle assignment during filter change"
  net/sched: flower: fix filter idr initialization
  net: fec: correct the counting of XDP sent frames
  bonding: add xdp_features support
  net: enetc: check the index of the SFI rather than the handle
  sfc: Add back mailing list
  virtio_net: suppress cpu stall when free_unused_bufs
  ice: block LAN in case of VF to VF offload
  net: dsa: mt7530: fix network connectivity with multiple CPU ports
  net: dsa: mt7530: fix corrupt frames using trgmii on 40 MHz XTAL MT7621
  9p: Remove INET dependency
  netfilter: nf_tables: fix ct untracked match breakage
  af_packet: Don't send zero-byte data in packet_sendmsg_spkt().
  igc: read before write to SRRCTL register
  pds_core: add AUXILIARY_BUS and NET_DEVLINK to Kconfig
  pds_core: remove CONFIG_DEBUG_FS from makefile
  ionic: catch failure from devlink_alloc
  ...
2023-05-05 19:12:01 -07:00
Jason Andryuk
d7385ba137 9p: Remove INET dependency
9pfs can run over assorted transports, so it doesn't have an INET
dependency.  Drop it and remove the includes of linux/inet.h.

NET_9P_FD/trans_fd.o builds without INET or UNIX and is usable over
plain file descriptors.  However, tcp and unix functionality is still
built and would generate runtime failures if used.  Add imply INET and
UNIX to NET_9P_FD, so functionality is enabled by default but can still
be explicitly disabled.

This allows configuring 9pfs over Xen with INET and UNIX disabled.

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-04 21:46:57 +01:00
Eric Van Hensbergen
21e26d5e54
fs/9p: Fix bit operation logic error
This re-introduces a fix that somehow got dropped during rebase of the
current series in for-next.  When writeback is enabled, opens
are forced to support both read and write operations but with the
logic error other flags may be dropped unintentionaly.

Reported-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2023-04-28 16:59:26 +00:00
Eric Van Hensbergen
4eb3117888
fs/9p: Rework cache modes and add new options to Documentation
Switch cache modes to a bit-mask and use legacy
cache names as shortcuts.  Update documentation to
include information on both shortcuts and bitmasks.

This patch also fixes missing guards related to fscache.

Update the documentation for new mount flags
and cache modes.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2023-04-09 21:41:21 +00:00
Eric Van Hensbergen
1543b4c507
fs/9p: remove writeback fid and fix per-file modes
This patch removes the creating of an additional writeback_fid
for opened files.  The patch addresses problems when files
were opened write-only or getattr on files with dirty caches.

This patch also incorporates information about cache behavior
in the fid for every file.  This allows us to reflect cache
behavior from mount flags, open mode, and information from
the server to inform readahead and writeback behavior.

This includes adding support for a 9p semantic that qid.version==0
is used to mark a file as non-cachable which is important for
synthetic files.  This may have a side-effect of not supporting
caching on certain legacy file servers that do not properly set
qid.version.  There is also now a mount flag which can disable
the qid.version behavior.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2023-03-27 02:33:48 +00:00
Eric Van Hensbergen
d9bc0d11e3
fs/9p: Consolidate file operations and add readahead and writeback
We had 3 different sets of file operations across 2 different protocol
variants differentiated by cache which really only changed 3
functions.  But the real problem is that certain file modes, mount
options, and other factors weren't being considered when we
decided whether or not to use caches.

This consolidates all the operations and switches
to conditionals within a common set to decide whether or not
to do different aspects of caching.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
2023-03-27 02:33:39 +00:00
Linus Torvalds
3808330b20 9p patches for 6.3 merge window (part 1)
Here is the 9p patches for the 6.3 merge window combining
 the tested and reviewed patches from both Dominique's
 for-next tree and my for-next tree.  Most of these
 patches have been in for-next since December with only
 some reword in the description:
 
 - some fixes and cleanup setting up for a larger set
   of performance patches I've been working on
 - a contributed fixes relating to 9p/rdma
 - some contributed fixes relating to 9p/xen
 
 I've marked this as part 1, I'm not sure I'll be
 submitting part 2.  There were several performance
 patches that I wanted to get in, but the revisions
 after review only went out last week so while they
 have been tested, I haven't received reviews on the
 revisions.
 
 Its been about a decade since I've submitted a pull
 request, sorry if I messed anything up.
 
        -eric
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEElpbw0ZalkJikytFRiP/V+0pf/5gFAmP/frIACgkQiP/V+0pf
 /5jb2w//dccypyaurk441RSdbsIVZUqf8aiGDzRSyX/iZBrUU4nmavdx8+qycpvc
 MVdD3WBiv7+PvdyYnt6EUGZYweGbI7vbVrpUpf20aq1q5A5oDWIR8K1EfrTUJQAd
 j69ALc4Qbq4FmX7kBOKYuj+qUvnnrcyDFQwTHTQ6o8d0MtpmW7MZr2kUiCDKeN3m
 8K2uemR83Azjb2m5TvhWRSjb+61cf03W/Jw4+8PsbtfzX8MyGblqUsgODi35IdiJ
 c2aO+JF0Cw4y9ulw7PR9SkX0yi6CY4Ll/pGV9xW0liIs6E6FQboiwczr+SZNzQoc
 TUC3S7bGSyodiCNTp685sK3KfHaxj5QHBvilUL/t7cgjOWwWSkl8neg9sbI8Bc7P
 WxQ4p6cqnMXMJiHAxk70QfIvCsabLSfTjBhN5zAUwjLmjQsxboFWHloKwndea49v
 32NHEhGwEt7QSE1WHdJ4m6xfuNRSayriOoQ28Yxyg8ekpK+7bWkI8CXGS3Cq9kGQ
 SGhX/UZqT5J1YCvBAwh9s7d5hhHUBxaVz74Pssvbd/PkeKI0CiXFoJM5cu32F+p2
 4gsY67NcyUjJZOq0NsUxFTqQXw4jdrnkcrnGD4istRFyDMf/3hhuV/F+SvPhBn0l
 GdMDwXjEkZLSYQi14TADp/V5DfDzRGRpquo++XbqikQyAgoNcKI=
 =Cvvf
 -----END PGP SIGNATURE-----

Merge tag '9p-6.3-for-linus-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

Pull 9p updates from Eric Van Hensbergen:

 - some fixes and cleanup setting up for a larger set of performance
   patches I've been working on

 - a contributed fixes relating to 9p/rdma

 - some contributed fixes relating to 9p/xen

* tag '9p-6.3-for-linus-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  fs/9p: fix error reporting in v9fs_dir_release
  net/9p: fix bug in client create for .L
  9p/rdma: unmap receive dma buffer in rdma_request()/post_recv()
  9p/xen: fix connection sequence
  9p/xen: fix version parsing
  fs/9p: Expand setup of writeback cache to all levels
  net/9p: Adjust maximum MSIZE to account for p9 header
2023-03-01 08:52:49 -08:00
Eric Van Hensbergen
344504e912
fs/9p: Expand setup of writeback cache to all levels
If cache is enabled, make sure we are putting the right things
in place (mainly impacts mmap).  This also sets us up for more
cache levels.

Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
2023-02-23 22:39:36 +00:00
Christian Brauner
5ebb29bee8
fs: port ->mknod() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00
Christian Brauner
c54bd91e9e
fs: port ->mkdir() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00
Christian Brauner
7a77db9551
fs: port ->symlink() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Christian Brauner
6c960e68aa
fs: port ->create() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Christian Brauner
b74d24f7a7
fs: port ->getattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Christian Brauner
c1632a0f11
fs: port ->setattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:02 +01:00
Linus Torvalds
e3b862ed89 9p-for-6.2-rc1
- improve p9_check_errors to check buffer size instead of msize when possible
 (e.g. not zero-copy)
 - some more syzbot and KCSAN fixes
 - minor headers include cleanup
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAmOljPwACgkQq06b7GqY
 5nDRjw//aJU+tdcKCMije/ul4hMWDlvMwxn7x6p0ELdomefs+ykS/knBxXSVIoEs
 PrbVJVZVqOOOAn/IwWe8cMBD+hal0fLUErRbfrtzmOdkiF7z8PavJ209OeJLKBgD
 ffL+bq6FhcVC6jVXcwVHoZkX9bb4pnM7/lsJrO0UjBw+fT3ceqtK0vsTa+R2xEOj
 9lOS5124u69GVa9UvwQzqHko+UUx5T6XlULZYjNBEdtJqGULGi2oAABrae64R3N2
 auaj5LRKzAFOx4zkJ+crCH1h08uZ4bfTyCHpfCeTHwWb1duKD3u4jMq9PhdetF4E
 A6NYnOdeMxbV/sZfFOjjNWQrzP1TQJLmF6IVGSZkVQrlCjrZh7xQ5dr/AHrKr6be
 U+NXb0UCmAS6/Gs7Sxq5jnihDHzJ4rYG+oFdYdNrwPrrpQXsYmmRh+bm61m/t40T
 2JxBIiSt2KWL487AHsKisb6OsiH65N1ojntO5QJObZId4UdnhFJU6OaAzqv0Cojv
 mqKlZ0UPyxICXNCL227w+SdDFgK25efdLF1Z1547hS5DO0+43oWAtnvd3KrRpjZ6
 CmV9ARvdhHt49lNedbxmJAre5FusJQLeULuRzhMbd4mdcG7mKAmGTdM3u+AlFRIu
 Te1ZotTJXxs16Yn/whWRShAooUnK9FbXzC3kViiibziYZlCfK+s=
 =xLkl
 -----END PGP SIGNATURE-----

Merge tag '9p-for-6.2-rc1' of https://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:

 - improve p9_check_errors to check buffer size instead of msize when
   possible (e.g. not zero-copy)

 - some more syzbot and KCSAN fixes

 - minor headers include cleanup

* tag '9p-for-6.2-rc1' of https://github.com/martinetd/linux:
  9p/client: fix data race on req->status
  net/9p: fix response size check in p9_check_errors()
  net/9p: distinguish zero-copy requests
  9p/xen: do not memcpy header into req->rc
  9p: set req refcount to zero to avoid uninitialized usage
  9p/net: Remove unneeded idr.h #include
  9p/fs: Remove unneeded idr.h #include
2022-12-23 11:39:18 -08:00
Christophe JAILLET
6e0149a553 9p/fs: Remove unneeded idr.h #include
The 9p fs does not use IDR or IDA functionalities. So there is no point in
including <linux/idr.h>.
Remove it.

Link: https://lkml.kernel.org/r/3d1e0ed9714eaee7e18d9f5b0b4bfa49b00b286d.1669553950.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
[Dominique: reword subject]
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2022-12-02 23:59:15 +09:00
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
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
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
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
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
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
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
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
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
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