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Commit Graph

3682 Commits

Author SHA1 Message Date
Trond Myklebust
714fbc7388 SUNRPC: RPC level errors should always set task->tk_rpc_status
Ensure that we set task->tk_rpc_status for all RPC level errors so that
the caller can distinguish between those and server reply status errors.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-17 15:14:11 -04:00
Trond Myklebust
45835a63d0 SUNRPC: Don't receive TCP data into a request buffer that has been reset
If we've removed the request from the receive list, and have added
it back after resetting the request receive buffer, then we should
only receive message data if it is a new reply (i.e. if
transport->recv.copied is zero).

Fixes: 277e4ab7d5 ("SUNRPC: Simplify TCP receive code by switching...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-17 15:14:11 -04:00
Trond Myklebust
cc204d0126 SUNRPC: Dequeue the request from the receive queue while we're re-encoding
Ensure that we dequeue the request from the transport receive queue
while we're re-encoding to prevent issues like use-after-free when
we release the bvec.

Fixes: 7536908982 ("SUNRPC: Ensure the bvecs are reset when we re-encode...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-09-17 15:14:11 -04:00
Chuck Lever
98ef77d1aa xprtrdma: Send Queue size grows after a reconnect
Eli Dorfman reports that after a series of idle disconnects, an
RPC/RDMA transport becomes unusable (rdma_create_qp returns
-ENOMEM). Problem was tracked down to increasing Send Queue size
after each reconnect.

The rdma_create_qp() API does not promise to leave its @qp_init_attr
parameter unaltered. In fact, some drivers do modify one or more of
its fields. Thus our calls to rdma_create_qp must use a fresh copy
of ib_qp_init_attr each time.

This fix is appropriate for kernels dating back to late 2007, though
it will have to be adapted, as the connect code has changed over the
years.

Reported-by: Eli Dorfman <eli@vastdata.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-26 15:45:38 -04:00
Chuck Lever
f9e1afe0fa xprtrdma: Clear xprt->reestablish_timeout on close
Ensure that the re-establishment delay does not grow exponentially
on each good reconnect. This probably should have been part of
commit 675dd90ad0 ("xprtrdma: Modernize ops->connect").

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-26 15:34:59 -04:00
Chuck Lever
ee2f412ece xprtrdma: Recycle MRs after disconnect
The optimization done in "xprtrdma: Simplify rpcrdma_mr_pop" was a
bit too optimistic. MRs left over after a reconnect still need to
be recycled, not added back to the free list, since they could be
in flight or actually fully registered.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-26 15:22:31 -04:00
Chuck Lever
435eba4ae0 xprtrdma: Optimize rpcrdma_post_recvs()
Micro-optimization: In rpcrdma_post_recvs, since commit e340c2d6ef
("xprtrdma: Reduce the doorbell rate (Receive)"), the common case is
to return without doing anything. Found with perf.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 15:04:59 -04:00
Chuck Lever
1738de336e xprtrdma: Inline XDR chunk encoder functions
Micro-optimization: Save the cost of three function calls during
transport header encoding.

These were "noinline" before to generate more meaningful call stacks
during debugging, but this code is now pretty stable.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 14:48:41 -04:00
Chuck Lever
17d47f93bc xprtrdma: Fix bc_max_slots return value
For the moment the returned value just happens to be correct because
the current backchannel server implementation does not vary the
number of credits it offers. The spec does permit this value to
change during the lifetime of a connection, however.

The actual maximum is fixed for all RPC/RDMA transports, because
each transport instance has to pre-allocate the resources for
processing BC requests. That's the value that should be returned.

Fixes: 7402a4fedc ("SUNRPC: Fix up backchannel slot table ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 14:35:49 -04:00
Chuck Lever
2a7f77c7be xprtrdma: Clean up xprt_rdma_set_connect_timeout()
Clean up: The function name should match the documenting comment.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 11:53:42 -04:00
Chuck Lever
b0b227f071 xprtrdma: Use an llist to manage free rpcrdma_reps
rpcrdma_rep objects are removed from their free list by only a
single thread: the Receive completion handler. Thus that free list
can be converted to an llist, where a single-threaded consumer and
a multi-threaded producer (rpcrdma_buffer_put) can both access the
llist without the need for any serialization.

This eliminates spin lock contention between the Receive completion
handler and rpcrdma_buffer_get, and makes the rep consumer wait-
free.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 11:45:27 -04:00
Chuck Lever
4d6b8890dd xprtrdma: Remove rpcrdma_buffer::rb_mrlock
Clean up: Now that the free list is used sparingly, get rid of the
separate spin lock protecting it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 11:40:00 -04:00
Chuck Lever
6dc6ec9e04 xprtrdma: Cache free MRs in each rpcrdma_req
Instead of a globally-contended MR free list, cache MRs in each
rpcrdma_req as they are released. This means acquiring and releasing
an MR will be lock-free in the common case, even outside the
transport send lock.

The original idea of per-rpcrdma_req MR free lists was suggested by
Shirley Ma <shirley.ma@oracle.com> several years ago. I just now
figured out how to make that idea work with on-demand MR allocation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-21 11:06:24 -04:00
Chuck Lever
805a1f620b xprtrdma: Ensure creating an MR does not trigger FS writeback
Probably would be good to also pass GFP flags to ib_alloc_mr.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 16:35:30 -04:00
Chuck Lever
3b39f52a02 xprtrdma: Move rpcrdma_mr_get out of frwr_map
Refactor: Retrieve an MR and handle error recovery entirely in
rpc_rdma.c, as this is not a device-specific function.

Note that since commit 89f90fe1ad ("SUNRPC: Allow calls to
xprt_transmit() to drain the entire transmit queue"), the
xprt_transmit function handles the cond_resched. The transport no
longer has to do this itself.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 16:23:35 -04:00
Chuck Lever
1ca3f4c054 xprtrdma: Combine rpcrdma_mr_put and rpcrdma_mr_unmap_and_put
Clean up. There is only one remaining rpcrdma_mr_put call site, and
it can be directly replaced with unmap_and_put because mr->mr_dir is
set to DMA_NONE just before the call.

Now all the call sites do a DMA unmap, and we can just rename
mr_unmap_and_put to mr_put, which nicely matches mr_get.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 16:11:56 -04:00
Chuck Lever
265a38d461 xprtrdma: Simplify rpcrdma_mr_pop
Clean up: rpcrdma_mr_pop call sites check if the list is empty
first. Let's replace the list_empty with less costly logic.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 16:03:41 -04:00
Chuck Lever
395790566e xprtrdma: Toggle XPRT_CONGESTED in xprtrdma's slot methods
Commit 48be539dd4 ("xprtrdma: Introduce ->alloc_slot call-out for
xprtrdma") added a separate alloc_slot and free_slot to the RPC/RDMA
transport. Later, commit 75891f502f ("SUNRPC: Support for
congestion control when queuing is enabled") modified the generic
alloc/free_slot methods, but neglected the methods in xprtrdma.

Found via code review.

Fixes: 75891f502f ("SUNRPC: Support for congestion control ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 14:06:03 -04:00
Chuck Lever
eed48a9c16 xprtrdma: Rename rpcrdma_buffer::rb_all
Clean up: There are other "all" list heads. For code clarity
distinguish this one as for use only for MRs by renaming it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 13:56:45 -04:00
Chuck Lever
2dfdcd88cf xprtrdma: Rename CQE field in Receive trace points
Make the field name the same for all trace points that handle
pointers to struct rpcrdma_rep. That makes it easy to grep for
matching rep points in trace output.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 13:48:43 -04:00
Chuck Lever
f3c66a2f56 xprtrdma: Boost maximum transport header size
Although I haven't seen any performance results that justify it,
I've received several complaints that NFS/RDMA no longer supports
a maximum rsize and wsize of 1MB. These days it is somewhat smaller.

To simplify the logic that determines whether a chunk list is
necessary, the implementation uses a fixed maximum size of the
transport header. Currently that maximum size is 256 bytes, one
quarter of the default inline threshold size for RPC/RDMA v1.

Since commit a78868497c ("xprtrdma: Reduce max_frwr_depth"), the
size of chunks is also smaller to take advantage of inline page
lists in device internal MR data structures.

The combination of these two design choices has reduced the maximum
NFS rsize and wsize that can be used for most RNIC/HCAs. Increasing
the maximum transport header size and the maximum number of RDMA
segments it can contain increases the negotiated maximum rsize/wsize
on common RNIC/HCAs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 11:09:46 -04:00
Chuck Lever
36bdd9056b xprtrdma: Fix calculation of ri_max_segs again
Commit 302d3deb20 ("xprtrdma: Prevent inline overflow") added this
calculation back in 2016, but got it wrong. I tested only the lower
bound, which is why there is a max_t there. The upper bound should be
rounded up too.

Now, when using DIV_ROUND_UP, that takes care of the lower bound as
well.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 11:01:03 -04:00
Chuck Lever
af08a7754a xprtrdma: Update obsolete comment
Comment was made obsolete by commit 8cec3dba76 ("xprtrdma:
rpcrdma_regbuf alignment").

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 10:56:24 -04:00
Chuck Lever
2fb2a4d529 xprtrdma: Refresh the documenting comment in frwr_ops.c
Things have changed since this comment was written. In particular,
the reworking of connection closing, on-demand creation of MRs, and
the removal of fr_state all mean that deferring MR recovery to
frwr_map is no longer needed. The description is obsolete.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 10:51:35 -04:00
Chuck Lever
95bd8304b3 SUNRPC: Inline xdr_commit_encode
Micro-optimization: For xdr_commit_encode call sites in
net/sunrpc/xdr.c, eliminate the extra calling sequence.  On my
client, this change saves about a microsecond for every 30 calls
to xdr_reserve_space().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 10:28:50 -04:00
Chuck Lever
691b45ddbd SUNRPC: Remove rpc_wake_up_queued_task_on_wq()
Clean up: commit c544577dad ("SUNRPC: Clean up transport write
space handling") appears to have removed the last caller of
rpc_wake_up_queued_task_on_wq().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-08-20 10:02:22 -04:00
Linus Torvalds
933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Linus Torvalds
249be8511b Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:
 "The rest of MM and a kernel-wide procfs cleanup.

  Summary of the more significant patches:

   - Patch series "mm/memory_hotplug: Factor out memory block
     devicehandling", v3. David Hildenbrand.

     Some spring-cleaning of the memory hotplug code, notably in
     drivers/base/memory.c

   - "mm: thp: fix false negative of shmem vma's THP eligibility". Yang
     Shi.

     Fix /proc/pid/smaps output for THP pages used in shmem.

   - "resource: fix locking in find_next_iomem_res()" + 1. Nadav Amit.

     Bugfix and speedup for kernel/resource.c

   - Patch series "mm: Further memory block device cleanups", David
     Hildenbrand.

     More spring-cleaning of the memory hotplug code.

   - Patch series "mm: Sub-section memory hotplug support". Dan
     Williams.

     Generalise the memory hotplug code so that pmem can use it more
     completely. Then remove the hacks from the libnvdimm code which
     were there to work around the memory-hotplug code's constraints.

   - "proc/sysctl: add shared variables for range check", Matteo Croce.

     We have about 250 instances of

          int zero;
          ...
                  .extra1 = &zero,

     in the tree. This is a tree-wide sweep to make all those private
     "zero"s and "one"s use global variables.

     Alas, it isn't practical to make those two global integers const"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (38 commits)
  proc/sysctl: add shared variables for range check
  mm: migrate: remove unused mode argument
  mm/sparsemem: cleanup 'section number' data types
  libnvdimm/pfn: stop padding pmem namespaces to section alignment
  libnvdimm/pfn: fix fsdax-mode namespace info-block zero-fields
  mm/devm_memremap_pages: enable sub-section remap
  mm: document ZONE_DEVICE memory-model implications
  mm/sparsemem: support sub-section hotplug
  mm/sparsemem: prepare for sub-section ranges
  mm: kill is_dev_zone() helper
  mm/hotplug: kill is_dev_zone() usage in __remove_pages()
  mm/sparsemem: convert kmalloc_section_memmap() to populate_section_memmap()
  mm/hotplug: prepare shrink_{zone, pgdat}_span for sub-section removal
  mm/sparsemem: add helpers track active portions of a section at boot
  mm/sparsemem: introduce a SECTION_IS_EARLY flag
  mm/sparsemem: introduce struct mem_section_usage
  drivers/base/memory.c: get rid of find_memory_block_hinted()
  mm/memory_hotplug: move and simplify walk_memory_blocks()
  mm/memory_hotplug: rename walk_memory_range() and pass start+size instead of pfns
  mm: make register_mem_sect_under_node() static
  ...
2019-07-19 09:45:58 -07:00
Matteo Croce
eec4844fae proc/sysctl: add shared variables for range check
In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range.  This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.

On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.

The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:

    $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
    248

Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.

This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:

    # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
    add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
    Data                                         old     new   delta
    sysctl_vals                                    -      12     +12
    __kstrtab_sysctl_vals                          -      12     +12
    max                                           14      10      -4
    int_max                                       16       -     -16
    one                                           68       -     -68
    zero                                         128      28    -100
    Total: Before=20583249, After=20583085, chg -0.00%

[mcroce@redhat.com: tipc: remove two unused variables]
  Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
  Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18 17:08:07 -07:00
Linus Torvalds
6860c981b9 NFS client updates for Linux 5.3
Highlights include:
 
 Stable fixes:
 - SUNRPC: Ensure bvecs are re-synced when we re-encode the RPC request
 - Fix an Oops in ff_layout_track_ds_error due to a PTR_ERR() dereference
 - Revert buggy NFS readdirplus optimisation
 - NFSv4: Handle the special Linux file open access mode
 - pnfs: Fix a problem where we gratuitously start doing I/O through the MDS
 
 Features:
 - Allow NFS client to set up multiple TCP connections to the server using
    a new 'nconnect=X' mount option. Queue length is used to balance load.
 - Enhance statistics reporting to report on all transports when using
    multiple connections.
 - Speed up SUNRPC by removing bh-safe spinlocks
 - Add a mechanism to allow NFSv4 to request that containers set a
    unique per-host identifier for when the hostname is not set.
 - Ensure NFSv4 updates the lease_time after a clientid update
 
 Bugfixes and cleanup:
 - Fix use-after-free in rpcrdma_post_recvs
 - Fix a memory leak when nfs_match_client() is interrupted
 - Fix buggy file access checking in NFSv4 open for execute
 - disable unsupported client side deduplication
 - Fix spurious client disconnections
 - Fix occasional RDMA transport deadlock
 - Various RDMA cleanups
 - Various tracepoint fixes
 - Fix the TCP callback channel to guarantee the server can actually send
    the number of callback requests that was negotiated at mount time.
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Merge tag 'nfs-for-5.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

  Stable fixes:

   - SUNRPC: Ensure bvecs are re-synced when we re-encode the RPC
     request

   - Fix an Oops in ff_layout_track_ds_error due to a PTR_ERR()
     dereference

   - Revert buggy NFS readdirplus optimisation

   - NFSv4: Handle the special Linux file open access mode

   - pnfs: Fix a problem where we gratuitously start doing I/O through
     the MDS

  Features:

   - Allow NFS client to set up multiple TCP connections to the server
     using a new 'nconnect=X' mount option. Queue length is used to
     balance load.

   - Enhance statistics reporting to report on all transports when using
     multiple connections.

   - Speed up SUNRPC by removing bh-safe spinlocks

   - Add a mechanism to allow NFSv4 to request that containers set a
     unique per-host identifier for when the hostname is not set.

   - Ensure NFSv4 updates the lease_time after a clientid update

  Bugfixes and cleanup:

   - Fix use-after-free in rpcrdma_post_recvs

   - Fix a memory leak when nfs_match_client() is interrupted

   - Fix buggy file access checking in NFSv4 open for execute

   - disable unsupported client side deduplication

   - Fix spurious client disconnections

   - Fix occasional RDMA transport deadlock

   - Various RDMA cleanups

   - Various tracepoint fixes

   - Fix the TCP callback channel to guarantee the server can actually
     send the number of callback requests that was negotiated at mount
     time"

* tag 'nfs-for-5.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (68 commits)
  pnfs/flexfiles: Add tracepoints for detecting pnfs fallback to MDS
  pnfs: Fix a problem where we gratuitously start doing I/O through the MDS
  SUNRPC: Optimise transport balancing code
  SUNRPC: Ensure the bvecs are reset when we re-encode the RPC request
  pnfs/flexfiles: Fix PTR_ERR() dereferences in ff_layout_track_ds_error
  NFSv4: Don't use the zero stateid with layoutget
  SUNRPC: Fix up backchannel slot table accounting
  SUNRPC: Fix initialisation of struct rpc_xprt_switch
  SUNRPC: Skip zero-refcount transports
  SUNRPC: Replace division by multiplication in calculation of queue length
  NFSv4: Validate the stateid before applying it to state recovery
  nfs4.0: Refetch lease_time after clientid update
  nfs4: Rename nfs41_setup_state_renewal
  nfs4: Make nfs4_proc_get_lease_time available for nfs4.0
  nfs: Fix copy-and-paste error in debug message
  NFS: Replace 16 seq_printf() calls by seq_puts()
  NFS: Use seq_putc() in nfs_show_stats()
  Revert "NFS: readdirplus optimization by cache mechanism" (memleak)
  SUNRPC: Fix transport accounting when caller specifies an rpc_xprt
  NFS: Record task, client ID, and XID in xdr_status trace points
  ...
2019-07-18 14:32:33 -07:00
Trond Myklebust
f554af280a SUNRPC: Optimise transport balancing code
Moves the balancing code to avoid doing cursor changes on every search
iteration.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-18 14:43:52 -04:00
Trond Myklebust
7536908982 SUNRPC: Ensure the bvecs are reset when we re-encode the RPC request
The bvec tracks the list of pages, so if the number of pages changes
due to a re-encode, we need to reset the bvec as well.

Fixes: 277e4ab7d5 ("SUNRPC: Simplify TCP receive code by switching...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.20+
2019-07-18 14:43:52 -04:00
Trond Myklebust
7402a4fedc SUNRPC: Fix up backchannel slot table accounting
Add a per-transport maximum limit in the socket case, and add
helpers to allow the NFSv4 code to discover that limit.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-18 01:12:59 -04:00
Trond Myklebust
9f98effc19 SUNRPC: Fix initialisation of struct rpc_xprt_switch
Ensure that we do initialise the fields xps_nactive, xps_queuelen
and xps_net.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-18 01:12:59 -04:00
Trond Myklebust
163f88211c SUNRPC: Skip zero-refcount transports
When looking for the next transport to use for an RPC call, skip those
that are in the process of being destroyed and that have a zero refcount.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-16 07:11:58 -04:00
Trond Myklebust
3cf7292280 SUNRPC: Replace division by multiplication in calculation of queue length
When checking whether or not a particular xprt queue length is shorter
than the average queue length for all xprts, prefer to use multiplication
rather than division for performance reasons.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-16 07:11:58 -04:00
Linus Torvalds
f632a8170a Driver Core and debugfs changes for 5.3-rc1
Here is the "big" driver core and debugfs changes for 5.3-rc1
 
 It's a lot of different patches, all across the tree due to some api
 changes and lots of debugfs cleanups.  Because of this, there is going
 to be some merge issues with your tree at the moment, I'll follow up
 with the expected resolutions to make it easier for you.
 
 Other than the debugfs cleanups, in this set of changes we have:
 	- bus iteration function cleanups (will cause build warnings
 	  with s390 and coresight drivers in your tree)
 	- scripts/get_abi.pl tool to display and parse Documentation/ABI
 	  entries in a simple way
 	- cleanups to Documenatation/ABI/ entries to make them parse
 	  easier due to typos and other minor things
 	- default_attrs use for some ktype users
 	- driver model documentation file conversions to .rst
 	- compressed firmware file loading
 	- deferred probe fixes
 
 All of these have been in linux-next for a while, with a bunch of merge
 issues that Stephen has been patient with me for.  Other than the merge
 issues, functionality is working properly in linux-next :)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...
2019-07-12 12:24:03 -07:00
Trond Myklebust
a101b043c4 SUNRPC: Fix transport accounting when caller specifies an rpc_xprt
Ensure that we do the required accounting for the round robin queue
when the caller to rpc_init_task() has passed in a transport to be
used.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Reported-by: Neil Brown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-07-12 13:14:54 -04:00
Trond Myklebust
347543e640 Merge tag 'nfs-rdma-for-5.3-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
NFSoRDMA client updates for 5.3

New features:
- Add a way to place MRs back on the free list
- Reduce context switching
- Add new trace events

Bugfixes and cleanups:
- Fix a BUG when tracing is enabled with NFSv4.1
- Fix a use-after-free in rpcrdma_post_recvs
- Replace use of xdr_stream_pos in rpcrdma_marshal_req
- Fix occasional transport deadlock
- Fix show_nfs_errors macros, other tracing improvements
- Remove RPCRDMA_REQ_F_PENDING and fr_state
- Various simplifications and refactors
2019-07-12 12:11:01 -04:00
Linus Torvalds
1f7563f743 SCSI sg on 20190709
This topic branch covers a fundamental change in how our sg lists are
 allocated to make mq more efficient by reducing the size of the
 preallocated sg list.  This necessitates a large number of driver
 changes because the previous guarantee that if a driver specified
 SG_ALL as the size of its scatter list, it would get a non-chained
 list and didn't need to bother with scatterlist iterators is now
 broken and every driver *must* use scatterlist iterators.
 
 This was broken out as a separate topic because we need to convert all
 the drivers before pulling the trigger and unconverted drivers kept
 being found, necessitating a rebase.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI scatter-gather list updates from James Bottomley:
 "This topic branch covers a fundamental change in how our sg lists are
  allocated to make mq more efficient by reducing the size of the
  preallocated sg list.

  This necessitates a large number of driver changes because the
  previous guarantee that if a driver specified SG_ALL as the size of
  its scatter list, it would get a non-chained list and didn't need to
  bother with scatterlist iterators is now broken and every driver
  *must* use scatterlist iterators.

  This was broken out as a separate topic because we need to convert all
  the drivers before pulling the trigger and unconverted drivers kept
  being found, necessitating a rebase"

* tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
  scsi: core: don't preallocate small SGL in case of NO_SG_CHAIN
  scsi: lib/sg_pool.c: clear 'first_chunk' in case of no preallocation
  scsi: core: avoid preallocating big SGL for data
  scsi: core: avoid preallocating big SGL for protection information
  scsi: lib/sg_pool.c: improve APIs for allocating sg pool
  scsi: esp: use sg helper to iterate over scatterlist
  scsi: NCR5380: use sg helper to iterate over scatterlist
  scsi: wd33c93: use sg helper to iterate over scatterlist
  scsi: ppa: use sg helper to iterate over scatterlist
  scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist
  scsi: imm: use sg helper to iterate over scatterlist
  scsi: aha152x: use sg helper to iterate over scatterlist
  scsi: s390: zfcp_fc: use sg helper to iterate over scatterlist
  scsi: staging: unisys: visorhba: use sg helper to iterate over scatterlist
  scsi: usb: image: microtek: use sg helper to iterate over scatterlist
  scsi: pmcraid: use sg helper to iterate over scatterlist
  scsi: ipr: use sg helper to iterate over scatterlist
  scsi: mvumi: use sg helper to iterate over scatterlist
  scsi: lpfc: use sg helper to iterate over scatterlist
  scsi: advansys: use sg helper to iterate over scatterlist
  ...
2019-07-11 15:17:41 -07:00
Linus Torvalds
d2b6b4c832 Highlights:
- Add a new /proc/fs/nfsd/clients/ directory which exposes some
   long-requested information about NFSv4 clients (like open files) and
   allows forced revocation of client state.
 
 - Replace the global duplicate reply cache by a cache per network
   namespace; previously, a request in one network namespace could
   incorrectly match an entry from another, though we haven't seen this
   in production.  This is the last remaining container bug that I'm
   aware of; at this point you should be able to run separate nfsd's in
   each network namespace, each with their own set of exports, and
   everything should work.
 
 - Cleanup and modify lock code to show the pid of lockd as the owner of
   NLM locks.  This is the correct version of the bugfix originally
   attempted in b8eee0e90f "lockd: Show pid of lockd for remote locks".
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Merge tag 'nfsd-5.3' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Add a new /proc/fs/nfsd/clients/ directory which exposes some
     long-requested information about NFSv4 clients (like open files)
     and allows forced revocation of client state.

   - Replace the global duplicate reply cache by a cache per network
     namespace; previously, a request in one network namespace could
     incorrectly match an entry from another, though we haven't seen
     this in production. This is the last remaining container bug that
     I'm aware of; at this point you should be able to run separate
     nfsd's in each network namespace, each with their own set of
     exports, and everything should work.

   - Cleanup and modify lock code to show the pid of lockd as the owner
     of NLM locks. This is the correct version of the bugfix originally
     attempted in b8eee0e90f ("lockd: Show pid of lockd for remote
     locks")"

* tag 'nfsd-5.3' of git://linux-nfs.org/~bfields/linux: (34 commits)
  nfsd: Make __get_nfsdfs_client() static
  nfsd: Make two functions static
  nfsd: Fix misuse of strlcpy
  sunrpc/cache: remove the exporting of cache_seq_next
  nfsd: decode implementation id
  nfsd: create xdr_netobj_dup helper
  nfsd: allow forced expiration of NFSv4 clients
  nfsd: create get_nfsdfs_clp helper
  nfsd4: show layout stateids
  nfsd: show lock and deleg stateids
  nfsd4: add file to display list of client's opens
  nfsd: add more information to client info file
  nfsd: escape high characters in binary data
  nfsd: copy client's address including port number to cl_addr
  nfsd4: add a client info file
  nfsd: make client/ directory names small ints
  nfsd: add nfsd/clients directory
  nfsd4: use reference count to free client
  nfsd: rename cl_refcount
  nfsd: persist nfsd filesystem across mounts
  ...
2019-07-10 21:22:43 -07:00
Linus Torvalds
e6983afd92 \n
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Merge tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "This contains cleanups of the fsnotify name removal hook and also a
  patch to disable fanotify permission events for 'proc' filesystem"

* tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: get rid of fsnotify_nameremove()
  fsnotify: move fsnotify_nameremove() hook out of d_delete()
  configfs: call fsnotify_rmdir() hook
  debugfs: call fsnotify_{unlink,rmdir}() hooks
  debugfs: simplify __debugfs_remove_file()
  devpts: call fsnotify_unlink() hook
  tracefs: call fsnotify_{unlink,rmdir}() hooks
  rpc_pipefs: call fsnotify_{unlink,rmdir}() hooks
  btrfs: call fsnotify_rmdir() hook
  fsnotify: add empty fsnotify_{unlink,rmdir}() hooks
  fanotify: Disallow permission events for proc filesystem
2019-07-10 20:09:17 -07:00
Chuck Lever
675dd90ad0 xprtrdma: Modernize ops->connect
Adapt and apply changes that were made to the TCP socket connect
code. See the following commits for details on the purpose of
these changes:

Commit 7196dbb02e ("SUNRPC: Allow changing of the TCP timeout parameters on the fly")
Commit 3851f1cdb2 ("SUNRPC: Limit the reconnect backoff timer to the max RPC message timeout")
Commit 02910177ae ("SUNRPC: Fix reconnection timeouts")

Some common transport code is moved to xprt.c to satisfy the code
duplication police.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
5828cebad1 xprtrdma: Remove rpcrdma_req::rl_buffer
Clean up.

There is only one remaining function, rpcrdma_buffer_put(), that
uses this field. Its caller can supply a pointer to the correct
rpcrdma_buffer, enabling the removal of an 8-byte pointer field
from a frequently-allocated shared data structure.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
6a6c6def42 xprtrdma: Refactor chunk encoding
Clean up.

Move the "not present" case into the individual chunk encoders. This
improves code organization and readability.

The reason for the original organization was to optimize for the
case where there there are no chunks. The optimization turned out to
be inconsequential, so let's err on the side of code readability.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
9ef33ef5b6 xprtrdma: Streamline rpcrdma_post_recvs
rb_lock is contended between rpcrdma_buffer_create,
rpcrdma_buffer_put, and rpcrdma_post_recvs.

Commit e340c2d6ef ("xprtrdma: Reduce the doorbell rate (Receive)")
causes rpcrdma_post_recvs to take the rb_lock repeatedly when it
determines more Receives are needed. Streamline this code path so
it takes the lock just once in most cases to build the Receive
chain that is about to be posted.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
379d1bc5be xprtrdma: Simplify rpcrdma_rep_create
Clean up.

Commit 7c8d9e7c88 ("xprtrdma: Move Receive posting to Receive
handler") reduced the number of rpcrdma_rep_create call sites to
one. After that commit, the backchannel code no longer invokes it.

Therefore the free list logic added by commit d698c4a02e
("xprtrdma: Fix backchannel allocation of extra rpcrdma_reps") is
no longer necessary, and in fact adds some extra overhead that we
can do without.

Simply post any newly created reps. They will get added back to
the rb_recv_bufs list when they subsequently complete.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
0ab1152370 xprtrdma: Wake RPCs directly in rpcrdma_wc_send path
Eliminate a context switch in the path that handles RPC wake-ups
when a Receive completion has to wait for a Send completion.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
d8099feda4 xprtrdma: Reduce context switching due to Local Invalidation
Since commit ba69cd122e ("xprtrdma: Remove support for FMR memory
registration"), FRWR is the only supported memory registration mode.

We can take advantage of the asynchronous nature of FRWR's LOCAL_INV
Work Requests to get rid of the completion wait by having the
LOCAL_INV completion handler take care of DMA unmapping MRs and
waking the upper layer RPC waiter.

This eliminates two context switches when local invalidation is
necessary. As a side benefit, we will no longer need the per-xprt
deferred completion work queue.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00
Chuck Lever
40088f0e9b xprtrdma: Add mechanism to place MRs back on the free list
When a marshal operation fails, any MRs that were already set up for
that request are recycled. Recycling releases MRs and creates new
ones, which is expensive.

Since commit f287762308 ("xprtrdma: Chain Send to FastReg WRs")
was merged, recycling FRWRs is unnecessary. This is because before
that commit, frwr_map had already posted FAST_REG Work Requests,
so ownership of the MRs had already been passed to the NIC and thus
dealing with them had to be delayed until they completed.

Since that commit, however, FAST_REG WRs are posted at the same time
as the Send WR. This means that if marshaling fails, we are certain
the MRs are safe to simply unmap and place back on the free list
because neither the Send nor the FAST_REG WRs have been posted yet.
The kernel still has ownership of the MRs at this point.

This reduces the total number of MRs that the xprt has to create
under heavy workloads and makes the marshaling logic less brittle.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-07-09 10:30:25 -04:00