Commit Graph

5920 Commits

Author SHA1 Message Date
Linus Torvalds
582cd91f69 for-5.12/block-2021-02-17
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Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block

Pull core block updates from Jens Axboe:
 "Another nice round of removing more code than what is added, mostly
  due to Christoph's relentless pursuit of tech debt removal/cleanups.
  This pull request contains:

   - Two series of BFQ improvements (Paolo, Jan, Jia)

   - Block iov_iter improvements (Pavel)

   - bsg error path fix (Pan)

   - blk-mq scheduler improvements (Jan)

   - -EBUSY discard fix (Jan)

   - bvec allocation improvements (Ming, Christoph)

   - bio allocation and init improvements (Christoph)

   - Store bdev pointer in bio instead of gendisk + partno (Christoph)

   - Block trace point cleanups (Christoph)

   - hard read-only vs read-only split (Christoph)

   - Block based swap cleanups (Christoph)

   - Zoned write granularity support (Damien)

   - Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"

* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
  mm: simplify swapdev_block
  sd_zbc: clear zone resources for non-zoned case
  block: introduce blk_queue_clear_zone_settings()
  zonefs: use zone write granularity as block size
  block: introduce zone_write_granularity limit
  block: use blk_queue_set_zoned in add_partition()
  nullb: use blk_queue_set_zoned() to setup zoned devices
  nvme: cleanup zone information initialization
  block: document zone_append_max_bytes attribute
  block: use bi_max_vecs to find the bvec pool
  md/raid10: remove dead code in reshape_request
  block: mark the bio as cloned in bio_iov_bvec_set
  block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
  block: remove a layer of indentation in bio_iov_iter_get_pages
  block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
  block: remove the 1 and 4 vec bvec_slabs entries
  block: streamline bvec_alloc
  block: factor out a bvec_alloc_gfp helper
  block: move struct biovec_slab to bio.c
  block: reuse BIO_INLINE_VECS for integrity bvecs
  ...
2021-02-21 11:02:48 -08:00
Linus Torvalds
99f1a5872b Highlights:
- Update NFSv2 and NFSv3 XDR decoding functions
 - Further improve support for re-exporting NFS mounts
 - Convert NFSD stats to per-CPU counters
 - Add batch Receive posting to the server's RPC/RDMA transport
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Merge tag 'nfsd-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:

 - Update NFSv2 and NFSv3 XDR decoding functions

 - Further improve support for re-exporting NFS mounts

 - Convert NFSD stats to per-CPU counters

 - Add batch Receive posting to the server's RPC/RDMA transport

* tag 'nfsd-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (65 commits)
  nfsd: skip some unnecessary stats in the v4 case
  nfs: use change attribute for NFS re-exports
  NFSv4_2: SSC helper should use its own config.
  nfsd: cstate->session->se_client -> cstate->clp
  nfsd: simplify nfsd4_check_open_reclaim
  nfsd: remove unused set_client argument
  nfsd: find_cpntf_state cleanup
  nfsd: refactor set_client
  nfsd: rename lookup_clientid->set_client
  nfsd: simplify nfsd_renew
  nfsd: simplify process_lock
  nfsd4: simplify process_lookup1
  SUNRPC: Correct a comment
  svcrdma: DMA-sync the receive buffer in svc_rdma_recvfrom()
  svcrdma: Reduce Receive doorbell rate
  svcrdma: Deprecate stat variables that are no longer used
  svcrdma: Restore read and write stats
  svcrdma: Convert rdma_stat_sq_starve to a per-CPU counter
  svcrdma: Convert rdma_stat_recv to a per-CPU counter
  svcrdma: Refactor svc_rdma_init() and svc_rdma_clean_up()
  ...
2021-02-21 10:22:20 -08:00
J. Bruce Fields
3cc55f4434 nfs: use change attribute for NFS re-exports
When exporting NFS, we may as well use the real change attribute
returned by the original server instead of faking up a change attribute
from the ctime.

Note we can't do that by setting I_VERSION--that would also turn on the
logic in iversion.h which treats the lower bit specially, and that
doesn't make sense for NFS.

So instead we define a new export operation for filesystems like NFS
that want to manage the change attribute themselves.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-30 11:47:12 -05:00
Dai Ngo
02591f9feb NFSv4_2: SSC helper should use its own config.
Currently NFSv4_2 SSC helper, nfs_ssc, incorrectly uses GRACE_PERIOD
as its config. Fix by adding new config NFS_V4_2_SSC_HELPER which
depends on NFS_V4_2 and is automatically selected when NFSD_V4 is
enabled. Also removed the file name from a comment in nfs_ssc.c.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-28 10:55:37 -05:00
Christoph Hellwig
6808f7af96 nfs/blocklayout: remove cruft in bl_alloc_init_bio
bio_alloc never returns NULL when it can sleep.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-27 09:51:48 -07:00
Chuck Lever
2289e87b59 SUNRPC: Make trace_svc_process() display the RPC procedure symbolically
The next few patches will employ these strings to help make server-
side trace logs more human-readable. A similar technique is already
in use in kernel RPC client code.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:23 -05:00
Trond Myklebust
d29b468da4 pNFS/NFSv4: Improve rejection of out-of-order layouts
If a layoutget ends up being reordered w.r.t. a layoutreturn, e.g. due
to a layoutget-on-open not knowing a priori which file to lock, then we
must assume the layout is no longer being considered valid state by the
server.
Incrementally improve our ability to reject such states by using the
cached old stateid in conjunction with the plh_barrier to try to
identify them.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-24 20:52:31 -05:00
Trond Myklebust
1bcf34fdac pNFS/NFSv4: Update the layout barrier when we schedule a layoutreturn
When we're scheduling a layoutreturn, we need to ignore any further
incoming layouts with sequence ids that are going to be affected by the
layout return.

Fixes: 44ea8dfce0 ("NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-24 20:52:31 -05:00
Trond Myklebust
08bd8dbe88 pNFS/NFSv4: Try to return invalid layout in pnfs_layout_process()
If the server returns a new stateid that does not match the one in our
cache, then try to return the one we hold instead of just invalidating
it on the client side. This ensures that both client and server will
agree that the stateid is invalid.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-24 20:52:30 -05:00
Trond Myklebust
814b849713 pNFS/NFSv4: Fix a layout segment leak in pnfs_layout_process()
If the server returns a new stateid that does not match the one in our
cache, then pnfs_layout_process() will leak the layout segments returned
by pnfs_mark_layout_stateid_invalid().

Fixes: 9888d837f3 ("pNFS: Force a retry of LAYOUTGET if the stateid doesn't match our cache")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-24 20:52:30 -05:00
Trond Myklebust
896567ee7f NFS: nfs_igrab_and_active must first reference the superblock
Before referencing the inode, we must ensure that the superblock can be
referenced. Otherwise, we can end up with iput() calling superblock
operations that are no longer valid or accessible.

Fixes: ea7c38fef0 ("NFSv4: Ensure we reference the inode for return-on-close in delegreturn")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 16:29:28 -05:00
Trond Myklebust
113aac6d56 NFS: nfs_delegation_find_inode_server must first reference the superblock
Before referencing the inode, we must ensure that the superblock can be
referenced. Otherwise, we can end up with iput() calling superblock
operations that are no longer valid or accessible.

Fixes: e39d8a186e ("NFSv4: Fix an Oops during delegation callbacks")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 16:29:28 -05:00
Trond Myklebust
cb2856c597 NFS/pNFS: Fix a leak of the layout 'plh_outstanding' counter
If we exit _lgopen_prepare_attached() without setting a layout, we will
currently leak the plh_outstanding counter.

Fixes: 411ae722d1 ("pNFS: Wait for stale layoutget calls to complete in pnfs_update_layout()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:52 -05:00
Trond Myklebust
46c9ea1d4f NFS/pNFS: Don't leak DS commits in pnfs_generic_retry_commit()
We must ensure that we pass a layout segment to nfs_retry_commit() when
we're cleaning up after pnfs_bucket_alloc_ds_commits(). Otherwise,
requests that should be committed to the DS will get committed to the
MDS.
Do so by ensuring that pnfs_bucket_get_committing() always tries to
return a layout segment when it returns a non-empty page list.

Fixes: c84bea5944 ("NFS/pNFS: Simplify bucket layout segment reference counting")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:52 -05:00
Trond Myklebust
1757655d78 NFS/pNFS: Don't call pnfs_free_bucket_lseg() before removing the request
In pnfs_generic_clear_request_commit(), we try calling
pnfs_free_bucket_lseg() before we remove the request from the DS bucket.
That will always fail, since the point is to test for whether or not
that bucket is empty.

Fixes: c84bea5944 ("NFS/pNFS: Simplify bucket layout segment reference counting")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:52 -05:00
Trond Myklebust
2c8d5fc37f pNFS: Stricter ordering of layoutget and layoutreturn
If a layout return is in progress, we should wait for it to complete,
in case the layout segment we are picking up gets returned too.

Fixes: 30cb3ee299 ("pNFS: Handle NFS4ERR_OLD_STATEID on layoutreturn by bumping the state seqid")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:52 -05:00
Trond Myklebust
c18d1e17ba pNFS: Clean up pnfs_layoutreturn_free_lsegs()
Remove the check for whether or not the stateid is NULL, and fix up the
callers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:52 -05:00
Trond Myklebust
078000d02d pNFS: We want return-on-close to complete when evicting the inode
If the inode is being evicted, it should be safe to run return-on-close,
so we should do it to ensure we don't inadvertently leak layout segments.

Fixes: 1c5bd76d17 ("pNFS: Enable layoutreturn operation for return-on-close")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:51 -05:00
Trond Myklebust
67bbceedc9 pNFS: Mark layout for return if return-on-close was not sent
If the layout return-on-close failed because the layoutreturn was never
sent, then we should mark the layout for return again.

Fixes: 9c47b18cf7 ("pNFS: Ensure we do clear the return-on-close layout stateid on fatal errors")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:51 -05:00
Scott Mayhew
c98e9daa59 NFS: Adjust fs_context error logging
Several existing dprink()/dfprintk() calls were converted to use the new
mount API logging macros by commit ce8866f091 ("NFS: Attach
supplementary error information to fs_context").  If the fs_context was
not created using fsopen() then it will not have had a log buffer
allocated for it, and the new mount API logging macros will wind up
calling printk().

This can result in syslog messages being logged where previously there
were none... most notably "NFS4: Couldn't follow remote path", which can
happen if the client is auto-negotiating a protocol version with an NFS
server that doesn't support the higher v4.x versions.

Convert the nfs_errorf(), nfs_invalf(), and nfs_warnf() macros to check
for the existence of the fs_context's log buffer and call dprintk() if
it doesn't exist.  Add nfs_ferrorf(), nfs_finvalf(), and nfs_warnf(),
which do the same thing but take an NFS debug flag as an argument and
call dfprintk().  Finally, modify the "NFS4: Couldn't follow remote
path" message to use nfs_ferrorf().

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207385
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: ce8866f091 ("NFS: Attach supplementary error information to fs_context.")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-10 13:32:39 -05:00
Dave Wysochanski
3d1a90ab0e NFS4: Fix use-after-free in trace_event_raw_event_nfs4_set_lock
It is only safe to call the tracepoint before rpc_put_task() because
'data' is freed inside nfs4_lock_release (rpc_release).

Fixes: 48c9579a1a ("Adding stateid information to tracepoints")
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-01-06 12:34:57 -05:00
Linus Torvalds
74f602dc96 NFS client updates for Linux 5.11
Highlights include:
 
 Features:
 - NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
   support.
 - A series of patches to improve readdir performance, particularly with
   large directories.
 - Basic support for using NFS/RDMA with the pNFS files and flexfiles
   drivers.
 - Micro-optimisations for RDMA.
 - RDMA tracing improvements.
 
 Bugfixes:
 - Fix a long standing bug with xs_read_xdr_buf() when receiving partial
   pages (Dan Aloni).
 - Various fixes for getxattr and listxattr, when used over non-TCP
   transports.
 - Fixes for containerised NFS from Sargun Dhillon.
 - switch nfsiod to be an UNBOUND workqueue (Neil Brown).
 - READDIR should not ask for security label information if there is no
   LSM policy. (Olga Kornievskaia)
 - Avoid using interval-based rebinding with TCP in lockd (Calum Mackay).
 - A series of RPC and NFS layer fixes to support the NFSv4.2 READ_PLUS code.
 - A couple of fixes for pnfs/flexfiles read failover
 
 Cleanups:
 - Various cleanups for the SUNRPC xdr code in conjunction with the
   READ_PLUS fixes.
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Merge tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

  Features:

   - NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
     support

   - A series of patches to improve readdir performance, particularly
     with large directories

   - Basic support for using NFS/RDMA with the pNFS files and flexfiles
     drivers

   - Micro-optimisations for RDMA

   - RDMA tracing improvements

  Bugfixes:

   - Fix a long standing bug with xs_read_xdr_buf() when receiving
     partial pages (Dan Aloni)

   - Various fixes for getxattr and listxattr, when used over non-TCP
     transports

   - Fixes for containerised NFS from Sargun Dhillon

   - switch nfsiod to be an UNBOUND workqueue (Neil Brown)

   - READDIR should not ask for security label information if there is
     no LSM policy (Olga Kornievskaia)

   - Avoid using interval-based rebinding with TCP in lockd (Calum
     Mackay)

   - A series of RPC and NFS layer fixes to support the NFSv4.2
     READ_PLUS code

   - A couple of fixes for pnfs/flexfiles read failover

  Cleanups:

   - Various cleanups for the SUNRPC xdr code in conjunction with the
     READ_PLUS fixes"

* tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (90 commits)
  NFS/pNFS: Fix a typo in ff_layout_resend_pnfs_read()
  pNFS/flexfiles: Avoid spurious layout returns in ff_layout_choose_ds_for_read
  NFSv4/pnfs: Add tracing for the deviceid cache
  fs/lockd: convert comma to semicolon
  NFSv4.2: fix error return on memory allocation failure
  NFSv4.2/pnfs: Don't use READ_PLUS with pNFS yet
  NFSv4.2: Deal with potential READ_PLUS data extent buffer overflow
  NFSv4.2: Don't error when exiting early on a READ_PLUS buffer overflow
  NFSv4.2: Handle hole lengths that exceed the READ_PLUS read buffer
  NFSv4.2: decode_read_plus_hole() needs to check the extent offset
  NFSv4.2: decode_read_plus_data() must skip padding after data segment
  NFSv4.2: Ensure we always reset the result->count in decode_read_plus()
  SUNRPC: When expanding the buffer, we may need grow the sparse pages
  SUNRPC: Cleanup - constify a number of xdr_buf helpers
  SUNRPC: Clean up open coded setting of the xdr_stream 'nwords' field
  SUNRPC: _copy_to/from_pages() now check for zero length
  SUNRPC: Cleanup xdr_shrink_bufhead()
  SUNRPC: Fix xdr_expand_hole()
  SUNRPC: Fixes for xdr_align_data()
  SUNRPC: _shift_data_left/right_pages should check the shift length
  ...
2020-12-17 12:15:03 -08:00
Trond Myklebust
52104f274e NFS/pNFS: Fix a typo in ff_layout_resend_pnfs_read()
Don't bump the index twice.

Fixes: 563c53e73b ("NFS: Fix flexfiles read failover")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-16 17:25:24 -05:00
Trond Myklebust
9bfffea352 pNFS/flexfiles: Avoid spurious layout returns in ff_layout_choose_ds_for_read
The callers of ff_layout_choose_ds_for_read() should decide whether or
not they want to return the layout on error. Sometimes, we may just want
to retry from the beginning.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-16 17:25:24 -05:00
Trond Myklebust
cac1d3a2b8 NFSv4/pnfs: Add tracing for the deviceid cache
Add tracepoints to allow debugging of the deviceid cache.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-16 17:25:24 -05:00
Colin Ian King
7be9b38afa NFSv4.2: fix error return on memory allocation failure
Currently when an alloc_page fails the error return is not set in
variable err and a garbage initialized value is returned. Fix this
by setting err to -ENOMEM before taking the error return path.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: a1f26739cc ("NFSv4.2: improve page handling for GETXATTR")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-16 07:54:42 -05:00
Linus Torvalds
f986e35083 Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - lots of little subsystems

 - a few post-linux-next MM material. Most of the rest awaits more
   merging of other trees.

Subsystems affected by this series: alpha, procfs, misc, core-kernel,
bitmap, lib, lz4, checkpatch, nilfs, kdump, rapidio, gcov, bfs, relay,
resource, ubsan, reboot, fault-injection, lzo, apparmor, and mm (swap,
memory-hotplug, pagemap, cleanups, and gup).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (86 commits)
  mm: fix some spelling mistakes in comments
  mm: simplify follow_pte{,pmd}
  mm: unexport follow_pte_pmd
  apparmor: remove duplicate macro list_entry_is_head()
  lib/lzo/lzo1x_compress.c: make lzogeneric1x_1_compress() static
  fault-injection: handle EI_ETYPE_TRUE
  reboot: hide from sysfs not applicable settings
  reboot: allow to override reboot type if quirks are found
  reboot: remove cf9_safe from allowed types and rename cf9_force
  reboot: allow to specify reboot mode via sysfs
  reboot: refactor and comment the cpu selection code
  lib/ubsan.c: mark type_check_kinds with static keyword
  kcov: don't instrument with UBSAN
  ubsan: expand tests and reporting
  ubsan: remove UBSAN_MISC in favor of individual options
  ubsan: enable for all*config builds
  ubsan: disable UBSAN_TRAP for all*config
  ubsan: disable object-size sanitizer under GCC
  ubsan: move cc-option tests into Kconfig
  ubsan: remove redundant -Wno-maybe-uninitialized
  ...
2020-12-15 23:26:37 -08:00
Andy Shevchenko
aa6159ab99 kernel.h: split out mathematical helpers
kernel.h is being used as a dump for all kinds of stuff for a long time.
Here is the attempt to start cleaning it up by splitting out
mathematical helpers.

At the same time convert users in header and lib folder to use new
header.  Though for time being include new header back to kernel.h to
avoid twisted indirected includes for existing users.

[sfr@canb.auug.org.au: fix powerpc build]
  Link: https://lkml.kernel.org/r/20201029150809.13059608@canb.auug.org.au

Link: https://lkml.kernel.org/r/20201028173212.41768-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 22:46:15 -08:00
Linus Torvalds
1a50ede2b3 Highlights:
- Improve support for re-exporting NFS mounts
 - Replace NFSv4 XDR decoding C macros with xdr_stream helpers
 - Support for multiple RPC/RDMA chunks per RPC transaction
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Merge tag 'nfsd-5.11' of git://git.linux-nfs.org/projects/cel/cel-2.6

Pull nfsd updates from Chuck Lever:
 "Several substantial changes this time around:

   - Previously, exporting an NFS mount via NFSD was considered to be an
     unsupported feature. With v5.11, the community has attempted to
     make re-exporting a first-class feature of NFSD.

     This would enable the Linux in-kernel NFS server to be used as an
     intermediate cache for a remotely-located primary NFS server, for
     example, even with other NFS server implementations, like a NetApp
     filer, as the primary.

   - A short series of patches brings support for multiple RPC/RDMA data
     chunks per RPC transaction to the Linux NFS server's RPC/RDMA
     transport implementation.

     This is a part of the RPC/RDMA spec that the other premiere
     NFS/RDMA implementation (Solaris) has had for a very long time, and
     completes the implementation of RPC/RDMA version 1 in the Linux
     kernel's NFS server.

   - Long ago, NFSv4 support was introduced to NFSD using a series of C
     macros that hid dprintk's and goto's. Over time, the kernel's XDR
     implementation has been greatly improved, but these C macros have
     remained and become fallow. A series of patches in this pull
     request completely replaces those macros with the use of current
     kernel XDR infrastructure. Benefits include:

       - More robust input sanitization in NFSD's NFSv4 XDR decoders.

       - Make it easier to use common kernel library functions that use
         XDR stream APIs (for example, GSS-API).

       - Align the structure of the source code with the RFCs so it is
         easier to learn, verify, and maintain our XDR implementation.

       - Removal of more than a hundred hidden dprintk() call sites.

       - Removal of some explicit manipulation of pages to help make the
         eventual transition to xdr->bvec smoother.

   - On top of several related fixes in 5.10-rc, there are a few more
     fixes to get the Linux NFSD implementation of NFSv4.2 inter-server
     copy up to speed.

  And as usual, there is a pinch of seasoning in the form of a
  collection of unrelated minor bug fixes and clean-ups.

  Many thanks to all who contributed this time around!"

* tag 'nfsd-5.11' of git://git.linux-nfs.org/projects/cel/cel-2.6: (131 commits)
  nfsd: Record NFSv4 pre/post-op attributes as non-atomic
  nfsd: Set PF_LOCAL_THROTTLE on local filesystems only
  nfsd: Fix up nfsd to ensure that timeout errors don't result in ESTALE
  exportfs: Add a function to return the raw output from fh_to_dentry()
  nfsd: close cached files prior to a REMOVE or RENAME that would replace target
  nfsd: allow filesystems to opt out of subtree checking
  nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations
  Revert "nfsd4: support change_attr_type attribute"
  nfsd4: don't query change attribute in v2/v3 case
  nfsd: minor nfsd4_change_attribute cleanup
  nfsd: simplify nfsd4_change_info
  nfsd: only call inode_query_iversion in the I_VERSION case
  nfs_common: need lock during iterate through the list
  NFSD: Fix 5 seconds delay when doing inter server copy
  NFSD: Fix sparse warning in nfs4proc.c
  SUNRPC: Remove XDRBUF_SPARSE_PAGES flag in gss_proxy upcall
  sunrpc: clean-up cache downcall
  nfsd: Fix message level for normal termination
  NFSD: Remove macros that are no longer used
  NFSD: Replace READ* macros in nfsd4_decode_compound()
  ...
2020-12-15 18:52:30 -08:00
Trond Myklebust
5c3485bb12 NFSv4.2/pnfs: Don't use READ_PLUS with pNFS yet
We have no way of tracking server READ_PLUS support in pNFS for now, so
just disable it.

Reported-by: "Mkrtchyan, Tigran" <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:08 -05:00
Trond Myklebust
7aedc687c9 NFSv4.2: Deal with potential READ_PLUS data extent buffer overflow
If the server returns more data than we have buffer space for, then
we need to truncate and exit early.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:08 -05:00
Trond Myklebust
503b934a75 NFSv4.2: Don't error when exiting early on a READ_PLUS buffer overflow
Expanding the READ_PLUS extents can cause the read buffer to overflow.
If it does, then don't error, but just exit early.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:08 -05:00
Trond Myklebust
dac3b1059b NFSv4.2: Handle hole lengths that exceed the READ_PLUS read buffer
If a hole extends beyond the READ_PLUS read buffer, then we want to fill
just the remaining buffer with zeros. Also ignore eof...

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:08 -05:00
Trond Myklebust
82f98c8b11 NFSv4.2: decode_read_plus_hole() needs to check the extent offset
The server is allowed to return a hole extent with an offset that starts
before the offset supplied in the READ_PLUS argument. Ensure that we
support that case too.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:07 -05:00
Trond Myklebust
5c4afe2ab6 NFSv4.2: decode_read_plus_data() must skip padding after data segment
All XDR opaque object sizes are 32-bit aligned, and a data segment is no
exception.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:07 -05:00
Trond Myklebust
1ee6310119 NFSv4.2: Ensure we always reset the result->count in decode_read_plus()
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:07 -05:00
Geliang Tang
1f70ea7009 NFSv4.1: use BITS_PER_LONG macro in nfs4session.h
Use the existing BITS_PER_LONG macro instead of calculating the value.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:07 -05:00
Frank van der Linden
a1f26739cc NFSv4.2: improve page handling for GETXATTR
XDRBUF_SPARSE_PAGES can cause problems for the RDMA transport,
and it's easy enough to allocate enough pages for the request
up front, so do that.

Also, since we've allocated the pages anyway, use the full
page aligned length for the receive buffer. This will allow
caching of valid replies that are too large for the caller,
but that still fit in the allocated pages.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-14 06:51:07 -05:00
Anna Schumaker
21e31401fc NFS: Disable READ_PLUS by default
We've been seeing failures with xfstests generic/091 and generic/263
when using READ_PLUS. I've made some progress on these issues, and the
tests fail later on but still don't pass. Let's disable READ_PLUS by
default until we can work out what is going on.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-12-10 16:48:03 -05:00
Dai Ngo
fe8eb820e3 NFSv4.2: Fix 5 seconds delay when doing inter server copy
Since commit b4868b44c5 ("NFSv4: Wait for stateid updates after
CLOSE/OPEN_DOWNGRADE"), every inter server copy operation suffers 5
seconds delay regardless of the size of the copy. The delay is from
nfs_set_open_stateid_locked when the check by nfs_stateid_is_sequential
fails because the seqid in both nfs4_state and nfs4_stateid are 0.

Fix __nfs42_ssc_open to delay setting of NFS_OPEN_STATE in nfs4_state,
until after the call to update_open_stateid, to indicate this is the 1st
open. This fix is part of a 2 patches, the other patch is the fix in the
source server to return the stateid for COPY_NOTIFY request with seqid 1
instead of 0.

Fixes: ce0887ac96 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-12-10 16:48:03 -05:00
Chuck Lever
1c87b85162 NFS: Fix rpcrdma_inline_fixup() crash with new LISTXATTRS operation
By switching to an XFS-backed export, I am able to reproduce the
ibcomp worker crash on my client with xfstests generic/013.

For the failing LISTXATTRS operation, xdr_inline_pages() is called
with page_len=12 and buflen=128.

- When ->send_request() is called, rpcrdma_marshal_req() does not
  set up a Reply chunk because buflen is smaller than the inline
  threshold. Thus rpcrdma_convert_iovs() does not get invoked at
  all and the transport's XDRBUF_SPARSE_PAGES logic is not invoked
  on the receive buffer.

- During reply processing, rpcrdma_inline_fixup() tries to copy
  received data into rq_rcv_buf->pages because page_len is positive.
  But there are no receive pages because rpcrdma_marshal_req() never
  allocated them.

The result is that the ibcomp worker faults and dies. Sometimes that
causes a visible crash, and sometimes it results in a transport hang
without other symptoms.

RPC/RDMA's XDRBUF_SPARSE_PAGES support is not entirely correct, and
should eventually be fixed or replaced. However, my preference is
that upper-layer operations should explicitly allocate their receive
buffers (using GFP_KERNEL) when possible, rather than relying on
XDRBUF_SPARSE_PAGES.

Reported-by: Olga kornievskaia <kolga@netapp.com>
Suggested-by: Olga kornievskaia <kolga@netapp.com>
Fixes: c10a75145f ("NFSv4.2: add the extended attribute proc functions.")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Olga kornievskaia <kolga@netapp.com>
Reviewed-by: Frank van der Linden <fllinden@amazon.com>
Tested-by: Olga kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-12-10 16:48:03 -05:00
Trond Myklebust
fa94a951bf NFSv4.2: Fix up the get/listxattr calls to rpc_prepare_reply_pages()
Ensure that both getxattr and listxattr page array are correctly
aligned, and that getxattr correctly accounts for the page padding word.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-10 09:01:53 -05:00
Trond Myklebust
716a8bc7f7 nfsd: Record NFSv4 pre/post-op attributes as non-atomic
For the case of NFSv4, specify to the client that the pre/post-op
attributes were not recorded atomically with the main operation.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09 09:39:38 -05:00
Trond Myklebust
01cbf38539 nfsd: Set PF_LOCAL_THROTTLE on local filesystems only
Don't set PF_LOCAL_THROTTLE on remote filesystems like NFS, since they
aren't expected to ever be subject to double buffering.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09 09:39:38 -05:00
Jeff Layton
7f84b488f9 nfsd: close cached files prior to a REMOVE or RENAME that would replace target
It's not uncommon for some workloads to do a bunch of I/O to a file and
delete it just afterward. If knfsd has a cached open file however, then
the file may still be open when the dentry is unlinked. If the
underlying filesystem is nfs, then that could trigger it to do a
sillyrename.

On a REMOVE or RENAME scan the nfsd_file cache for open files that
correspond to the inode, and proactively unhash and put their
references. This should prevent any delete-on-last-close activity from
occurring, solely due to knfsd's open file cache.

This must be done synchronously though so we use the variants that call
flush_delayed_fput. There are deadlock possibilities if you call
flush_delayed_fput while holding locks, however. In the case of
nfsd_rename, we don't even do the lookups of the dentries to be renamed
until we've locked for rename.

Once we've figured out what the target dentry is for a rename, check to
see whether there are cached open files associated with it. If there
are, then unwind all of the locking, close them all, and then reattempt
the rename.

None of this is really necessary for "typical" filesystems though. It's
mostly of use for NFS, so declare a new export op flag and use that to
determine whether to close the files beforehand.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09 09:39:38 -05:00
Jeff Layton
ba5e8187c5 nfsd: allow filesystems to opt out of subtree checking
When we start allowing NFS to be reexported, then we have some problems
when it comes to subtree checking. In principle, we could allow it, but
it would mean encoding parent info in the filehandles and there may not
be enough space for that in a NFSv3 filehandle.

To enforce this at export upcall time, we add a new export_ops flag
that declares the filesystem ineligible for subtree checking.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09 09:39:38 -05:00
Jeff Layton
daab110e47 nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations
With NFSv3 nfsd will always attempt to send along WCC data to the
client. This generally involves saving off the in-core inode information
prior to doing the operation on the given filehandle, and then issuing a
vfs_getattr to it after the op.

Some filesystems (particularly clustered or networked ones) have an
expensive ->getattr inode operation. Atomicity is also often difficult
or impossible to guarantee on such filesystems. For those, we're best
off not trying to provide WCC information to the client at all, and to
simply allow it to poll for that information as needed with a GETATTR
RPC.

This patch adds a new flags field to struct export_operations, and
defines a new EXPORT_OP_NOWCC flag that filesystems can use to indicate
that nfsd should not attempt to provide WCC info in NFSv3 replies. It
also adds a blurb about the new flags field and flag to the exporting
documentation.

The server will also now skip collecting this information for NFSv2 as
well, since that info is never used there anyway.

Note that this patch does not add this flag to any filesystem
export_operations structures. This was originally developed to allow
reexporting nfs via nfsd.

Other filesystems may want to consider enabling this flag too. It's hard
to tell however which ones have export operations to enable export via
knfsd and which ones mostly rely on them for open-by-filehandle support,
so I'm leaving that up to the individual maintainers to decide. I am
cc'ing the relevant lists for those filesystems that I think may want to
consider adding this though.

Cc: HPDD-discuss@lists.01.org
Cc: ceph-devel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: fuse-devel@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09 09:39:38 -05:00
NeilBrown
bf701b765e NFS: switch nfsiod to be an UNBOUND workqueue.
nfsiod is currently a concurrency-managed workqueue (CMWQ).
This means that workitems scheduled to nfsiod on a given CPU are queued
behind all other work items queued on any CMWQ on the same CPU.  This
can introduce unexpected latency.

Occaionally nfsiod can even cause excessive latency.  If the work item
to complete a CLOSE request calls the final iput() on an inode, the
address_space of that inode will be dismantled.  This takes time
proportional to the number of in-memory pages, which on a large host
working on large files (e.g..  5TB), can be a large number of pages
resulting in a noticable number of seconds.

We can avoid these latency problems by switching nfsiod to WQ_UNBOUND.
This causes each concurrent work item to gets a dedicated thread which
can be scheduled to an idle CPU.

There is precedent for this as several other filesystems use WQ_UNBOUND
workqueue for handling various async events.

Signed-off-by: NeilBrown <neilb@suse.de>
Fixes: ada609ee2a ("workqueue: use WQ_MEM_RECLAIM instead of WQ_RESCUER")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-02 14:05:54 -05:00
Sargun Dhillon
d3ff46fe69 NFSv4: Refactor to use user namespaces for nfs4idmap
In several patches work has been done to enable NFSv4 to use user
namespaces:
58002399da: NFSv4: Convert the NFS client idmapper to use the container user namespace
3b7eb5e35d: NFS: When mounting, don't share filesystems between different user namespaces

Unfortunately, the userspace APIs were only such that the userspace facing
side of the filesystem (superblock s_user_ns) could be set to a non init
user namespace. This furthers the fs_context related refactoring, and
piggybacks on top of that logic, so the superblock user namespace, and the
NFS user namespace are the same.

Users can still use rpc.idmapd if they choose to, but there are complexities
with user namespaces and request-key that have yet to be addresssed.

Eventually, we will need to at least:
  * Come up with an upcall mechanism that can be triggered inside of the container,
    or safely triggered outside, with the requisite context to do the right
    mapping. * Handle whatever refactoring needs to be done in net/sunrpc.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Tested-by: Alban Crequy <alban.crequy@gmail.com>
Fixes: 62a55d088c ("NFS: Additional refactoring for fs_context conversion")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-02 14:05:54 -05:00
Sargun Dhillon
d18a9d3fa0 NFS: NFSv2/NFSv3: Use cred from fs_context during mount
There was refactoring done to use the fs_context for mounting done in:
62a55d088c: NFS: Additional refactoring for fs_context conversion

This made it so that the net_ns is fetched from the fs_context (the netns
that fsopen is called in). This change also makes it so that the credential
fetched during fsopen is used as well as the net_ns.

NFS has already had a number of changes to prepare it for user namespaces:
1a58e8a0e5: NFS: Store the credential of the mount process in the nfs_server
264d948ce7: NFS: Convert NFSv3 to use the container user namespace
c207db2f5d: NFS: Convert NFSv2 to use the container user namespace

Previously, different credentials could be used for creation of the
fs_context versus creation of the nfs_server, as FSCONFIG_CMD_CREATE did
the actual credential check, and that's where current_creds() were fetched.
This meant that the user namespace which fsopen was called in could be a
non-init user namespace. This still requires that the user that calls
FSCONFIG_CMD_CREATE has CAP_SYS_ADMIN in the init user ns.

This roughly allows a privileged user to mount on behalf of an unprivileged
usernamespace, by forking off and calling fsopen in the unprivileged user
namespace. It can then pass back that fsfd to the privileged process which
can configure the NFS mount, and then it can call FSCONFIG_CMD_CREATE
before switching back into the mount namespace of the container, and finish
up the mounting process and call fsmount and move_mount.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Tested-by: Alban Crequy <alban.crequy@gmail.com>
Fixes: 62a55d088c ("NFS: Additional refactoring for fs_context conversion")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-12-02 14:05:54 -05:00