linux.git/fs/nfs/write.c, branch v6.9

Merge tag 'nfs-for-6.9-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2024-03-16T18:44:00+00:00

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Bugfixes:
   - Fix for an Oops in the NFSv4.2 listxattr handler
   - Correct an incorrect buffer size in listxattr
   - Fix for an Oops in the pNFS flexfiles layout
   - Fix a refcount leak in NFS O_DIRECT writes
   - Fix missing locking in NFS O_DIRECT
   - Avoid an infinite loop in pnfs_update_layout
   - Fix an overflow in the RPC waitqueue queue length counter
   - Ensure that pNFS I/O is also protected by TLS when xprtsec is
     specified by the mount options
   - Fix a leaked folio lock in the netfs read code
   - Fix a potential deadlock in fscache
   - Allow setting the fscache uniquifier in NFSv4
   - Fix an off by one in root_nfs_cat()
   - Fix another off by one in rpc_sockaddr2uaddr()
   - nfs4_do_open() can incorrectly trigger state recovery
   - Various fixes for connection shutdown

  Features and cleanups:
   - Ensure that containers only see their own RPC and NFS stats
   - Enable nconnect for RDMA
   - Remove dead code from nfs_writepage_locked()
   - Various tracepoint additions to track EXCHANGE_ID, GETDEVICEINFO,
     and mount options"

* tag 'nfs-for-6.9-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (29 commits)
  nfs: fix panic when nfs4_ff_layout_prepare_ds() fails
  NFS: trace the uniquifier of fscache
  NFS: Read unlock folio on nfs_page_create_from_folio() error
  NFS: remove unused variable nfs_rpcstat
  nfs: fix UAF in direct writes
  nfs: properly protect nfs_direct_req fields
  NFS: enable nconnect for RDMA
  NFSv4: nfs4_do_open() is incorrectly triggering state recovery
  NFS: avoid infinite loop in pnfs_update_layout.
  NFS: remove sync_mode test from nfs_writepage_locked()
  NFSv4.1/pnfs: fix NFS with TLS in pnfs
  NFS: Fix an off by one in root_nfs_cat()
  nfs: make the rpc_stat per net namespace
  nfs: expose /proc/net/sunrpc/nfs in net namespaces
  sunrpc: add a struct rpc_stats arg to rpc_create_args
  nfs: remove unused NFS_CALL macro
  NFSv4.1: add tracepoint to trunked nfs4_exchange_id calls
  NFS: Fix nfs_netfs_issue_read() xarray locking for writeback interrupt
  SUNRPC: increase size of rpc_wait_queue.qlen from unsigned short to unsigned int
  nfs: fix regression in handling of fsc= option in NFSv4
  ...

nfs: fix UAF in direct writes

2024-03-09T14:14:51+00:00

In production we have been hitting the following warning consistently

------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 17 PID: 1800359 at lib/refcount.c:28 refcount_warn_saturate+0x9c/0xe0
Workqueue: nfsiod nfs_direct_write_schedule_work [nfs]
RIP: 0010:refcount_warn_saturate+0x9c/0xe0
PKRU: 55555554
Call Trace:
 
 ? __warn+0x9f/0x130
 ? refcount_warn_saturate+0x9c/0xe0
 ? report_bug+0xcc/0x150
 ? handle_bug+0x3d/0x70
 ? exc_invalid_op+0x16/0x40
 ? asm_exc_invalid_op+0x16/0x20
 ? refcount_warn_saturate+0x9c/0xe0
 nfs_direct_write_schedule_work+0x237/0x250 [nfs]
 process_one_work+0x12f/0x4a0
 worker_thread+0x14e/0x3b0
 ? ZSTD_getCParams_internal+0x220/0x220
 kthread+0xdc/0x120
 ? __btf_name_valid+0xa0/0xa0
 ret_from_fork+0x1f/0x30

This is because we're completing the nfs_direct_request twice in a row.

The source of this is when we have our commit requests to submit, we
process them and send them off, and then in the completion path for the
commit requests we have

if (nfs_commit_end(cinfo.mds))
	nfs_direct_write_complete(dreq);

However since we're submitting asynchronous requests we sometimes have
one that completes before we submit the next one, so we end up calling
complete on the nfs_direct_request twice.

The only other place we use nfs_generic_commit_list() is in
__nfs_commit_inode, which wraps this call in a

nfs_commit_begin();
nfs_commit_end();

Which is a common pattern for this style of completion handling, one
that is also repeated in the direct code with get_dreq()/put_dreq()
calls around where we process events as well as in the completion paths.

Fix this by using the same pattern for the commit requests.

Before with my 200 node rocksdb stress running this warning would pop
every 10ish minutes.  With my patch the stress test has been running for
several hours without popping.

Signed-off-by: Josef Bacik 
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust

NFS: remove sync_mode test from nfs_writepage_locked()

2024-03-09T14:14:51+00:00

nfs_writepage_locked() is only called from nfs_wb_folio() (since Commit
12fc0a963128 ("nfs: Remove writepage")) so ->sync_mode is always
WB_SYNC_ALL.

This means the test for WB_SYNC_NONE is dead code and can be removed.

Signed-off-by: NeilBrown 
Signed-off-by: Trond Myklebust

nfs: adapt to breakup of struct file_lock

2024-02-05T12:11:43+00:00

Most of the existing APIs have remained the same, but subsystems that
access file_lock fields directly need to reach into struct
file_lock_core now.

Signed-off-by: Jeff Layton 
Link: https://lore.kernel.org/r/20240131-flsplit-v3-41-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown 
Signed-off-by: Christian Brauner

filelock: split common fields into struct file_lock_core

2024-02-05T12:11:38+00:00

In a future patch, we're going to split file leases into their own
structure. Since a lot of the underlying machinery uses the same fields
move those into a new file_lock_core, and embed that inside struct
file_lock.

For now, add some macros to ensure that we can continue to build while
the conversion is in progress.

Signed-off-by: Jeff Layton 
Link: https://lore.kernel.org/r/20240131-flsplit-v3-17-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown 
Signed-off-by: Christian Brauner

nfs: convert to using new filelock helpers

2024-02-05T12:11:36+00:00

Convert to using the new file locking helper functions. Also, in later
patches we're going to introduce some temporary macros with names that
clash with the variable name in nfs4_proc_unlck. Rename it.

Signed-off-by: Jeff Layton 
Link: https://lore.kernel.org/r/20240131-flsplit-v3-11-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown 
Signed-off-by: Christian Brauner

Merge tag 'nfs-for-6.8-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

2024-01-11T00:13:57+00:00

Pull nfs client updates from Anna Schumaker:
 "New Features:
   - Always ask for type with READDIR
   - Remove nfs_writepage()

  Bugfixes:
   - Fix a suspicious RCU usage warning
   - Fix a blocklayoutdriver reference leak
   - Fix the block driver's calculation of layoutget size
   - Fix handling NFS4ERR_RETURNCONFLICT
   - Fix _xprt_switch_find_current_entry()
   - Fix v4.1 backchannel request timeouts
   - Don't add zero-length pnfs block devices
   - Use the parent cred in nfs_access_login_time()

  Cleanups:
   - A few improvements when dealing with referring calls from the
     server
   - Clean up various unused variables, struct fields, and function
     calls
   - Various tracepoint improvements"

* tag 'nfs-for-6.8-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (21 commits)
  NFSv4.1: Use the nfs_client's rpc timeouts for backchannel
  SUNRPC: Fixup v4.1 backchannel request timeouts
  rpc_pipefs: Replace one label in bl_resolve_deviceid()
  nfs: Remove writepage
  NFS: drop unused nfs_direct_req bytes_left
  pNFS: Fix the pnfs block driver's calculation of layoutget size
  nfs: print fileid in lookup tracepoints
  nfs: rename the nfs_async_rename_done tracepoint
  nfs: add new tracepoint at nfs4 revalidate entry point
  SUNRPC: fix _xprt_switch_find_current_entry logic
  NFSv4.1/pnfs: Ensure we handle the error NFS4ERR_RETURNCONFLICT
  NFSv4.1: if referring calls are complete, trust the stateid argument
  NFSv4: Track the number of referring calls in struct cb_process_state
  NFS: Use parent's objective cred in nfs_access_login_time()
  NFSv4: Always ask for type with READDIR
  pnfs/blocklayout: Don't add zero-length pnfs_block_dev
  blocklayoutdriver: Fix reference leak of pnfs_device_node
  SUNRPC: Fix a suspicious RCU usage warning
  SUNRPC: Create a helper function for accessing the rpc_clnt's xprt_switch
  SUNRPC: Remove unused function rpc_clnt_xprt_switch_put()
  ...

nfs: Remove writepage

2024-01-04T15:47:56+00:00

NFS already has writepages and migrate_folio, so it does not need to
implement writepage.  The writepage operation is deprecated as it leads
to worse performance under high memory pressure due to folios being
written out in LRU order rather than sequentially within a file.

Signed-off-by: Matthew Wilcox (Oracle) 
Signed-off-by: Anna Schumaker

fs: Rename mapping private members

2023-11-21T10:57:10+00:00

It is hard to find where mapping->private_lock, mapping->private_list and
mapping->private_data are used, due to private_XXX being a relatively
common name for variables and structure members in the kernel.  To fit
with other members of struct address_space, rename them all to have an
i_ prefix.  Tested with an allmodconfig build.

Signed-off-by: Matthew Wilcox (Oracle) 
Link: https://lore.kernel.org/r/20231117215823.2821906-1-willy@infradead.org
Acked-by: Darrick J. Wong 
Reviewed-by: Josef Bacik 
Signed-off-by: Christian Brauner

NFSv4/pnfs: Allow layoutget to return EAGAIN for softerr mounts

2023-10-22T23:47:56+00:00

If we're using the 'softerr' mount option, we may want to allow
layoutget to return EAGAIN to allow knfsd server threads to return a
JUKEBOX/DELAY error to the client instead of busy waiting.

Signed-off-by: Trond Myklebust