stable inclusion
from stable-v5.10.111
commit c74e2f6ecc51bd08bb5b0335477dba954a50592e
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5GL1Z

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c74e2f6ecc51bd08bb5b0335477dba954a50592e

--------------------------------

[ Upstream commit 0bae835b ]

In a low memory situation, allow the NFS writeback code to fail without
getting stuck in infinite loops in mempool_alloc().
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>

stable inclusion
from stable-v5.10.111
commit 34681aeddcfcc0c47d45154f5d39310def87c55f
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5GL1Z

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=34681aeddcfcc0c47d45154f5d39310def87c55f

--------------------------------

[ Upstream commit 515dcdcd ]

The concern is that since nfsiod is sometimes required to kick off a
commit, it can get locked up waiting forever in mempool_alloc() instead
of failing gracefully and leaving the commit until later.

Try to allocate from the slab first, with GFP_KERNEL | __GFP_NORETRY,
then fall back to a non-blocking attempt to allocate from the memory
pool.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>

stable inclusion
from stable-v5.10.110
commit 469ce5119f221ecf09549d0fadf340344df0309e
bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=469ce5119f221ecf09549d0fadf340344df0309e

--------------------------------

[ Upstream commit 6c984083 ]

The use of mapping_set_error() in conjunction with calls to
filemap_check_errors() is problematic because every error gets reported
as either an EIO or an ENOSPC by filemap_check_errors() in functions
such as filemap_write_and_wait() or filemap_write_and_wait_range().
In almost all cases, we prefer to use the more nuanced wb errors.

Fixes: b8946d7b ("NFS: Revalidate the file mapping on all fatal writeback errors")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYu Liao <liaoyu15@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

stable inclusion
from stable-5.10.80
commit 10f21087173651d41ea308b4a0c3a13188418aaa
bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=10f21087173651d41ea308b4a0c3a13188418aaa

--------------------------------

[ Upstream commit 133a48ab ]

If O_DIRECT bumps the commit_info rpcs_out field, then that could lead
to fsync() hangs. The fix is to ensure that O_DIRECT calls
nfs_commit_end().

Fixes: 723c921e ("sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

stable inclusion
from stable-5.10.80
commit 3e7b08ebf40fd1283c1d005362fe2a81902e027a
bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3e7b08ebf40fd1283c1d005362fe2a81902e027a

--------------------------------

[ Upstream commit 64a93dbf ]

Partially revert commit 2ce209c4 ("NFS: Wait for requests that are
locked on the commit list"), since it can lead to deadlocks between
commit requests and nfs_join_page_group().
For now we should assume that any locked requests on the commit list are
either about to be removed and committed by another task, or the writes
they describe are about to be retransmitted. In either case, we should
not need to worry.

Fixes: 2ce209c4 ("NFS: Wait for requests that are locked on the commit list")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

After an NFS page has been written it is considered "unstable" until a
COMMIT request succeeds.  If the COMMIT fails, the page will be
re-written.

These "unstable" pages are currently accounted as "reclaimable", either
in WB_RECLAIMABLE, or in NR_UNSTABLE_NFS which is included in a
'reclaimable' count.  This might have made sense when sending the COMMIT
required a separate action by the VFS/MM (e.g.  releasepage() used to
send a COMMIT).  However now that all writes generated by ->writepages()
will automatically be followed by a COMMIT (since commit 919e3bd9
("NFS: Ensure we commit after writeback is complete")) it makes more
sense to treat them as writeback pages.

So this patch removes NR_UNSTABLE_NFS and accounts unstable pages in
NR_WRITEBACK and WB_WRITEBACK.

A particular effect of this change is that when
wb_check_background_flush() calls wb_over_bg_threshold(), the latter
will report 'true' a lot less often as the 'unstable' pages are no
longer considered 'dirty' (as there is nothing that writeback can do
about them anyway).

Currently wb_check_background_flush() will trigger writeback to NFS even
when there are relatively few dirty pages (if there are lots of unstable
pages), this can result in small writes going to the server (10s of
Kilobytes rather than a Megabyte) which hurts throughput.  With this
patch, there are fewer writes which are each larger on average.

Where the NR_UNSTABLE_NFS count was included in statistics
virtual-files, the entry is retained, but the value is hard-coded as
zero.  static trace points and warning printks which mentioned this
counter no longer report it.

[akpm@linux-foundation.org: re-layout comment]
[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Acked-by: Michal Hocko <mhocko@suse.com>	[mm]
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Link: http://lkml.kernel.org/r/87d06j7gqa.fsf@notabene.neil.brown.nameSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When we're doing pnfs then the credential being used for the RPC call
is not necessarily the same as the one used in the open context, so
don't use RPC_TASK_CRED_NOREF.

Fixes: 61296507 ("NFSv4: Avoid referencing the cred unnecessarily during NFSv4 I/O")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

If we have to retransmit requests, try to join their page groups
first.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Refactor nfs_lock_and_join_requests() in order to separate out the
subrequest merging into its own function nfs_lock_and_join_group()
that can be used by O_DIRECT.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Clean up nfs_lock_and_join_requests() to simplify the calculation
of the range covered by the page group, taking into account the
presence of mirrors.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

When a subrequest is being detached from the subgroup, we want to
ensure that it is not holding the group lock, or in the process
of waiting for the group lock.

Fixes: 5b2b5187 ("NFS: Fix nfs_page_group_destroy() and nfs_lock_and_join_requests() race cases")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

When we detach a subrequest from the list, we must also release the
reference it holds to the parent.

Fixes: 5b2b5187 ("NFS: Fix nfs_page_group_destroy() and nfs_lock_and_join_requests() race cases")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Instead of trying to save the commit verifiers and checking them against
previous writes, adopt the same strategy as for buffered writes, of
just checking the verifiers at commit time.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Refactor pnfs_generic_commit_pagelist() to simplify the conversion
to layout segment based commit lists.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

In read/write/commit, we should be able to assume that the cred is
pinned by the open context.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

If we're resending a write due to a short read or write, ensure we
reset the reply count to zero.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Clean up the generic file commit tracepoints to use a 64-bit value
for the verifier, and to display the pNFS filehandle, if it exists.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Clean up the generic writeback tracepoints so they do pass the
full structures as arguments. Also ensure we report the number
of bytes actually written.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Instead of making assumptions about the commit verifier contents, change
the commit code to ensure we always check that the verifier was set
by the XDR code.

Fixes: f54bcf2e ("pnfs: Prepare for flexfiles by pulling out common code")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

If a write or commit failed, and the mapping sees a fatal error, we
need to revalidate the contents of that mapping.

Fixes: 06c9fdf3 ("NFS: On fatal writeback errors, we need to call nfs_inode_remove_request()")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

If we suffer a fatal error upon writing a file, which causes us to
need to revalidate the entire mapping, then we should also revalidate
the file size.

Fixes: d2ceb7e5 ("NFS: Don't use page_file_mapping after removing the page")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Try to capture the reason for the writeback path tagging an error on
a page.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

When xfstests testing, there are some WARNING as below:

WARNING: CPU: 0 PID: 6235 at fs/nfs/inode.c:122 nfs_clear_inode+0x9c/0xd8
Modules linked in:
CPU: 0 PID: 6235 Comm: umount.nfs
Hardware name: linux,dummy-virt (DT)
pstate: 60000005 (nZCv daif -PAN -UAO)
pc : nfs_clear_inode+0x9c/0xd8
lr : nfs_evict_inode+0x60/0x78
sp : fffffc000f68fc00
x29: fffffc000f68fc00 x28: fffffe00c53155c0
x27: fffffe00c5315000 x26: fffffc0009a63748
x25: fffffc000f68fd18 x24: fffffc000bfaaf40
x23: fffffc000936d3c0 x22: fffffe00c4ff5e20
x21: fffffc000bfaaf40 x20: fffffe00c4ff5d10
x19: fffffc000c056000 x18: 000000000000003c
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000040 x14: 0000000000000228
x13: fffffc000c3a2000 x12: 0000000000000045
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000000 x8 : 0000000000000000
x7 : 0000000000000000 x6 : fffffc00084b027c
x5 : fffffc0009a64000 x4 : fffffe00c0e77400
x3 : fffffc000c0563a8 x2 : fffffffffffffffb
x1 : 000000000000764e x0 : 0000000000000001
Call trace:
 nfs_clear_inode+0x9c/0xd8
 nfs_evict_inode+0x60/0x78
 evict+0x108/0x380
 dispose_list+0x70/0xa0
 evict_inodes+0x194/0x210
 generic_shutdown_super+0xb0/0x220
 nfs_kill_super+0x40/0x88
 deactivate_locked_super+0xb4/0x120
 deactivate_super+0x144/0x160
 cleanup_mnt+0x98/0x148
 __cleanup_mnt+0x38/0x50
 task_work_run+0x114/0x160
 do_notify_resume+0x2f8/0x308
 work_pending+0x8/0x14

The nrequest should be increased/decreased only if PG_INODE_REF flag
was setted.

But in the nfs_inode_remove_request function, it maybe decrease when
no PG_INODE_REF flag, this maybe lead nrequests count error.
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Fixes gcc '-Wunused-but-set-variable' warning:

fs/nfs/write.c: In function nfs_page_async_flush:
fs/nfs/write.c:609:24: warning: variable mapping set but not used [-Wunused-but-set-variable]

It is not use since commit aefb623c422e ("NFS: Fix
writepage(s) error handling to not report errors twice")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

If writepage()/writepages() saw an error, but handled it without
reporting it, we should not be re-reporting that error on exit.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

If the client attempts to read a page, but the read fails due to some
spurious error (e.g. an ACCESS error or a timeout, ...) then we need
to allow other processes to retry.
Also try to report errors correctly when doing a synchronous readpage.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

If the writeback error is fatal, we need to remove the tracking structures
(i.e. the nfs_page) from the inode.

Fixes: 6fbda89b ("NFS: Replace custom error reporting mechanism...")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Now that the VM promises never to recurse back into the filesystem
layer on writeback, remove all the GFP_NOFS references etc from
the generic writeback code.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

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

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a helper for when we remove the explicit pointer to the open
context.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

When the client is reading or writing using pNFS, and hits an error
on the DS, then it typically sends a LAYOUTERROR and/or LAYOUTRETURN
to the MDS, before redirtying the failed pages, and going for a new
round of reads/writebacks. The problem is that if the server has no
way to fix the DS, then we may need a way to interrupt this loop
after a set number of attempts have been made.
This patch adds an optional module parameter that allows the admin
to specify how many times to retry the read/writeback process before
failing with a fatal error.
The default behaviour is to retry forever.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

All the callers of nfs_create_request() are now creating page group
heads, so we can remove the redundant 'last' page argument.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Replace the NFS custom error reporting mechanism with the generic
mapping_set_error().
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

The NFS read code can trigger writeback while holding the page lock.
If an error then triggers a call to nfs_write_error_remove_page(),
we can deadlock.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

When flushing out dirty pages, the fact that we may hit fatal errors
is not a reason to stop writeback. Those errors are reported through
fsync(), not through the flush mechanism.

Fixes: a6598813 ("NFS: Don't write back further requests if there...")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Fix up some compiler warnings about function parameters, etc not being
correctly described or formatted.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

All the allocations that we can hit in the NFS layer and sunrpc layers
themselves are already marked as GFP_NOFS, but we need to ensure that
any calls to generic kernel functionality do the right thing as well.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

Allow the caller to pass error information when cleaning up a failed
I/O request so that we can conditionally take action to cancel the
request altogether if the error turned out to be fatal.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

If nfs_page_async_flush() removes the page from the mapping, then we can't
use page_file_mapping() on it as nfs_updatepate() is wont to do when
receiving an error.  Instead, push the mapping to the stack before the page
is possibly truncated.

Fixes: 8fc75bed ("NFS: Fix up return value on fatal errors in nfs_page_async_flush()")
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Ensure that we return the fatal error value that caused us to exit
nfs_page_async_flush().

Fixes: c373fff7 ("NFSv4: Don't special case "launder"")
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.12+
Reviewed-by: NBenjamin Coddington <bcodding@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>