If we suspect that the server may have cleared the suid/sgid bit,
then mark the inode for revalidation.
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the setting of NFS_INO_INVALIDATING gets reordered to before the
clearing of NFS_INO_INVALID_DATA, then another task may hit a race
window where both appear to be clear, even though the inode's pages are
still in need of invalidation. Fix this by adding the appropriate memory
barriers.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There is a possible race in how the nfs_invalidate_mapping function is
handled. Currently, we go and invalidate the pages in the file and then
clear NFS_INO_INVALID_DATA.
The problem is that it's possible for a stale page to creep into the
mapping after the page was invalidated (i.e., via readahead). If another
writer comes along and sets the flag after that happens but before
invalidate_inode_pages2 returns then we could clear the flag
without the cache having been properly invalidated.
So, we must clear the flag first and then invalidate the pages. Doing
this however, opens another race:
It's possible to have two concurrent read() calls that end up in
nfs_revalidate_mapping at the same time. The first one clears the
NFS_INO_INVALID_DATA flag and then goes to call nfs_invalidate_mapping.
Just before calling that though, the other task races in, checks the
flag and finds it cleared. At that point, it trusts that the mapping is
good and gets the lock on the page, allowing the read() to be satisfied
from the cache even though the data is no longer valid.
These effects are easily manifested by running diotest3 from the LTP
test suite on NFS. That program does a series of DIO writes and buffered
reads. The operations are serialized and page-aligned but the existing
code fails the test since it occasionally allows a read to come out of
the cache incorrectly. While mixing direct and buffered I/O isn't
recommended, I believe it's possible to hit this in other ways that just
use buffered I/O, though that situation is much harder to reproduce.
The problem is that the checking/clearing of that flag and the
invalidation of the mapping really need to be atomic. Fix this by
serializing concurrent invalidations with a bitlock.
At the same time, we also need to allow other places that check
NFS_INO_INVALID_DATA to check whether we might be in the middle of
invalidating the file, so fix up a couple of places that do that
to look for the new NFS_INO_INVALIDATING flag.
Doing this requires us to be careful not to set the bitlock
unnecessarily, so this code only does that if it believes it will
be doing an invalidation.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We should always make sure the cached page is up-to-date when we're
determining whether we can extend a write to cover the full page -- even
if we've received a write delegation from the server.
Commit c7559663 added logic to skip this check if we have a write
delegation, which can lead to data corruption such as the following
scenario if client B receives a write delegation from the NFS server:
Client A:
# echo 123456789 > /mnt/file
Client B:
# echo abcdefghi >> /mnt/file
# cat /mnt/file
0�D0�abcdefghi
Just because we hold a write delegation doesn't mean that we've read in
the entire page contents.
Cc: <stable@vger.kernel.org> # v3.11+
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
A fileid in NFS is a uint64. There are some occurrences where dprintk()
outputs a signed fileid. This leads to confusion and more difficult to
read debugging (negative fileids matching positive inode numbers).
Signed-off-by: Niels de Vos <ndevos@redhat.com>
CC: Santosh Pradhan <spradhan@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we're doing buffered writes, and there is no file locking involved,
then we don't have to worry about whether or not the lock owner information
is identical.
By relaxing this check, we ensure that fork()ed child processes can write
to a page without having to first sync dirty data that was written
by the parent to disk.
Reported-by: Quentin Barnes <qbarnes@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Quentin Barnes <qbarnes@gmail.com>
WRITE and COMMIT can use the machine credential.
If WRITE is supported and COMMIT is not, make all (mach cred) writes FILE_SYNC4.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When an NFSv4 client loses contact with the server it can lose any
locks that it holds.
Currently when it reconnects to the server it simply tries to reclaim
those locks. This might succeed even though some other client has
held and released a lock in the mean time. So the first client might
think the file is unchanged, but it isn't. This isn't good.
If, when recovery happens, the locks cannot be claimed because some
other client still holds the lock, then we get a message in the kernel
logs, but the client can still write. So two clients can both think
they have a lock and can both write at the same time. This is equally
not good.
There was a patch a while ago
http://comments.gmane.org/gmane.linux.nfs/41917
which tried to address some of this, but it didn't seem to go
anywhere. That patch would also send a signal to the process. That
might be useful but for now this patch just causes writes to fail.
For NFSv4 (unlike v2/v3) there is a strong link between the lock and
the write request so we can fairly easily fail any IO of the lock is
gone. While some applications might not expect this, it is still
safer than allowing the write to succeed.
Because this is a fairly big change in behaviour a module parameter,
"recover_locks", is introduced which defaults to true (the current
behaviour) but can be set to "false" to tell the client not to try to
recover things that were lost.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We must avoid buffering a WRITE that is using a credential key (e.g. a GSS
context key) that is about to expire or has expired. We currently will
paint ourselves into a corner by returning success to the applciation
for such a buffered WRITE, only to discover that we do not have permission when
we attempt to flush the WRITE (and potentially associated COMMIT) to disk.
Use the RPC layer credential key timeout and expire routines which use a
a watermark, gss_key_expire_timeo. We test the key in nfs_file_write.
If a WRITE is using a credential with a key that will expire within
watermark seconds, flush the inode in nfs_write_end and send only
NFS_FILE_SYNC WRITEs by adding nfs_ctx_key_to_expire to nfs_need_sync_write.
Note that this results in single page NFS_FILE_SYNC WRITEs.
Signed-off-by: Andy Adamson <andros@netapp.com>
[Trond: removed a pr_warn_ratelimited() for now]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add tracepoints for inode attribute updates, attribute revalidation,
writeback start/end fsync start/end, attribute change start/end,
permission check start/end.
The intention is to enable performance tracing using 'perf'as well as
improving debugging.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently nfs_updatepage allows a write to be extended to cover a full
page only if we don't have a byte range lock lock on the file... but if
we have a write delegation on the file or if we have the whole file
locked for writing then we should be allowed to extend the write as
well.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
[Trond: fix up call to nfs_have_delegation()]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the state recovery failed, we want to ensure that the application
doesn't try to use the same file descriptor for more reads or writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch ensures that we free the rpc_task after the cleanup callbacks
are done in order to avoid a deadlock problem that can be triggered if
the callback needs to wait for another workqueue item to complete.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Weston Andros Adamson <dros@netapp.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Bruce Fields <bfields@fieldses.org>
Cc: stable@vger.kernel.org [>= 3.5]
nfs_migrate_page() does not wait for FS-Cache to finish with a page, probably
leading to the following bad-page-state:
BUG: Bad page state in process python-bin pfn:17d39b
page:ffffea00053649e8 flags:004000000000100c count:0 mapcount:0 mapping:(null)
index:38686 (Tainted: G B ---------------- )
Pid: 31053, comm: python-bin Tainted: G B ----------------
2.6.32-71.24.1.el6.x86_64 #1
Call Trace:
[<ffffffff8111bfe7>] bad_page+0x107/0x160
[<ffffffff8111ee69>] free_hot_cold_page+0x1c9/0x220
[<ffffffff8111ef19>] __pagevec_free+0x59/0xb0
[<ffffffff8104b988>] ? flush_tlb_others_ipi+0x128/0x130
[<ffffffff8112230c>] release_pages+0x21c/0x250
[<ffffffff8115b92a>] ? remove_migration_pte+0x28a/0x2b0
[<ffffffff8115f3f8>] ? mem_cgroup_get_reclaim_stat_from_page+0x18/0x70
[<ffffffff81122687>] ____pagevec_lru_add+0x167/0x180
[<ffffffff811226f8>] __lru_cache_add+0x58/0x70
[<ffffffff81122731>] lru_cache_add_lru+0x21/0x40
[<ffffffff81123f49>] putback_lru_page+0x69/0x100
[<ffffffff8115c0bd>] migrate_pages+0x13d/0x5d0
[<ffffffff81122687>] ? ____pagevec_lru_add+0x167/0x180
[<ffffffff81152ab0>] ? compaction_alloc+0x0/0x370
[<ffffffff8115255c>] compact_zone+0x4cc/0x600
[<ffffffff8111cfac>] ? get_page_from_freelist+0x15c/0x820
[<ffffffff810672f4>] ? check_preempt_wakeup+0x1c4/0x3c0
[<ffffffff8115290e>] compact_zone_order+0x7e/0xb0
[<ffffffff81152a49>] try_to_compact_pages+0x109/0x170
[<ffffffff8111e94d>] __alloc_pages_nodemask+0x5ed/0x850
[<ffffffff814c9136>] ? thread_return+0x4e/0x778
[<ffffffff81150d43>] alloc_pages_vma+0x93/0x150
[<ffffffff81167ea5>] do_huge_pmd_anonymous_page+0x135/0x340
[<ffffffff814cb6f6>] ? rwsem_down_read_failed+0x26/0x30
[<ffffffff81136755>] handle_mm_fault+0x245/0x2b0
[<ffffffff814ce383>] do_page_fault+0x123/0x3a0
[<ffffffff814cbdf5>] page_fault+0x25/0x30
nfs_migrate_page() calls nfs_fscache_release_page() which doesn't actually wait
- even if __GFP_WAIT is set. The reason that doesn't wait is that
fscache_maybe_release_page() might deadlock the allocator as the work threads
writing to the cache may all end up sleeping on memory allocation.
However, I wonder if that is actually a problem. There are a number of things
I can do to deal with this:
(1) Make nfs_migrate_page() wait.
(2) Make fscache_maybe_release_page() honour the __GFP_WAIT flag.
(3) Set a timeout around the wait.
(4) Make nfs_migrate_page() return an error if the page is still busy.
For the moment, I'll select (2) and (4).
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
The writeback code is already capable of passing errors back to user space
by means of the open_context->error. In the case of ENOSPC, Neil Brown
is reporting seeing 2 errors being returned.
Neil writes:
"e.g. if /mnt2/ if an nfs mounted filesystem that has no space then
strace dd if=/dev/zero conv=fsync >> /mnt2/afile count=1
reported Input/output error and the relevant parts of the strace output are:
write(1, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 512) = 512
fsync(1) = -1 EIO (Input/output error)
close(1) = -1 ENOSPC (No space left on device)"
Neil then shows that the duplication of error messages appears to be due to
the use of the PageError() mechanism, which causes filemap_fdatawait_range
to return the extra EIO. The regression was introduced by
commit 7b281ee026 (NFS: fsync() must exit
with an error if page writeback failed).
Fix this by removing the call to SetPageError(), and just relying on
open_context->error reporting the ENOSPC back to fsync().
Reported-by: Neil Brown <neilb@suse.de>
Tested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [3.6+]
Jian reported that the following sequence would leave "testfile" with
corrupt data:
# mount localhost:/export /mnt/nfs/ -o vers=3
# echo abc > /mnt/nfs/testfile; echo def >> /export/testfile; echo ghi >> /mnt/nfs/testfile
# cat -v /export/testfile
abc
^@^@^@^@ghi
While there's no locking involved here, the operations are serialized,
so CTO should prevent corruption.
The first write to the file is fine and writes 4 bytes. The file is then
extended on the server. When it's reopened a GETATTR is issued and the
size change is noticed. This causes NFS_INO_INVALID_DATA to be set on
the file. Because the file is opened for write only,
nfs_want_read_modify_write() returns 0 to nfs_write_begin().
nfs_updatepage then calls nfs_write_pageuptodate() to see if it should
extend the nfs_page to cover the whole page. NFS_INO_INVALID_DATA is
still set on the file at that point, but that flag is ignored and
nfs_pageuptodate erroneously extends the write to cover the whole page,
with the write done on the server side filled in with zeroes.
This patch just has that function check for NFS_INO_INVALID_DATA in
addition to NFS_INO_REVAL_PAGECACHE. This fixes the bug, but looking
over the code, I wonder if we might have a similar bug in
nfs_revalidate_size(). The difference between those two flags is very
subtle, so it seems like we ought to be checking for
NFS_INO_INVALID_DATA in most of the places that we look for
NFS_INO_REVAL_PAGECACHE.
I believe this is regression introduced by commit 8d197a568. The code
did check for NFS_INO_INVALID_DATA prior to that patch.
Original bug report is here:
https://bugzilla.redhat.com/show_bug.cgi?id=885743
Cc: <stable@vger.kernel.org> # 3.5+
Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The slab cache in nfs_commit_mempool is wrong, and I think it is just a slip.
I tested it on a x86-32 machine, the size of nfs_write_header is 544, and
the size of nfs_commit_data is 408, so it works fine. It is also true that
sizeof(struct nfs_write_header) > sizeof(struct nfs_commit_data) on other
platforms in my opinoin. Just fix it.
Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
...and ensure that we set the return value for nfs_page_async_flush()
to zero! (Reported-by: Dros Adamson)
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server reboots before it can commit the unstable writes to disk,
then nfs_commit_release_pages() will detect this when it compares the
verifier returned by COMMIT to the one returned by WRITE. When this
happens, the client needs to resend those writes in order to guarantee
that they make it to stable storage.
This patch adds a signalling mechanism to notify fsync() that it
needs to retry all writes before it can exit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to be able to pass on the information that the page was not
dirtied under a lock. Instead of adding a flag parameter, do this
by passing a pointer to a 'struct nfs_lock_owner' that may be NULL.
Also reuse this structure in struct nfs_lock_context to carry the
fl_owner_t and pid_t.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
...and ensure that we tear down the nfs_commit_data cache too when
unloading the module.
Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Merge Andrew's second set of patches:
- MM
- a few random fixes
- a couple of RTC leftovers
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits)
rtc/rtc-88pm80x: remove unneed devm_kfree
rtc/rtc-88pm80x: assign ret only when rtc_register_driver fails
mm: hugetlbfs: close race during teardown of hugetlbfs shared page tables
tmpfs: distribute interleave better across nodes
mm: remove redundant initialization
mm: warn if pg_data_t isn't initialized with zero
mips: zero out pg_data_t when it's allocated
memcg: gix memory accounting scalability in shrink_page_list
mm/sparse: remove index_init_lock
mm/sparse: more checks on mem_section number
mm/sparse: optimize sparse_index_alloc
memcg: add mem_cgroup_from_css() helper
memcg: further prevent OOM with too many dirty pages
memcg: prevent OOM with too many dirty pages
mm: mmu_notifier: fix freed page still mapped in secondary MMU
mm: memcg: only check anon swapin page charges for swap cache
mm: memcg: only check swap cache pages for repeated charging
mm: memcg: split swapin charge function into private and public part
mm: memcg: remove needless !mm fixup to init_mm when charging
mm: memcg: remove unneeded shmem charge type
...
GFP_NOFS is _more_ permissive than GFP_NOIO in that it will initiate IO,
just not of any filesystem data.
The problem is that previously NOFS was correct because that avoids
recursion into the NFS code. With swap-over-NFS, it is no longer correct
as swap IO can lead to this recursion.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Neil Brown <neilb@suse.de>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The VM does not like PG_private set on PG_swapcache pages. As suggested
by Trond in http://lkml.org/lkml/2006/8/25/348, this patch disables NFS
data cache revalidation on swap files. as it does not make sense to have
other clients change the file while it is being used as swap. This avoids
setting PG_private on swap pages, since there ought to be no further races
with invalidate_inode_pages2() to deal with.
Since we cannot set PG_private we cannot use page->private which is
already used by PG_swapcache pages to store the nfs_page. Thus augment
the new nfs_page_find_request logic.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Neil Brown <neilb@suse.de>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace all relevant occurences of page->index and page->mapping in the
NFS client with the new page_file_index() and page_file_mapping()
functions.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Neil Brown <neilb@suse.de>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch exports symbols needed by the v4 module. In addition, I also
switch over to using IS_ENABLED() to check if CONFIG_NFS_V4 or
CONFIG_NFS_V4_MODULE are set.
The module (nfs4.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v4.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch exports symbols and moves over the final structures needed by
the v3 module. In addition, I also switch over to using IS_ENABLED() to
check if CONFIG_NFS_V3 or CONFIG_NFS_V3_MODULE are set.
The module (nfs3.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v3.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The module (nfs2.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v2.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Somehow I missed this in my previous patch series, but these functions
are only needed by the v4 code and should be moved to a v4-only file. I
wasn't exactly sure where I should put these functions, so I moved them
into nfs4super.c where I could make them static.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This gives pnfs a chance to do a layout commit inside the v4 code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
pNFS needs to select a write function based on the layout driver
currently in use, so I let each NFS version decide how to best handle
initializing writes.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Delegations are a v4 feature, so push them out of the generic code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The 'committed' field is not needed once we have put the struct nfs_page
on the right list.
Also correct the type of the verifier: it is not an array of __be32, but
simply an 8 byte long opaque array.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The new commit code fails to copy the verifier into the wb_verf field
of _all_ the nfs_page structures; it only copies it into the first entry.
The consequence is that most requests end up failing to match in
nfs_commit_release.
Fix is to copy the verifier into the req->wb_verf field in
nfs_write_completion.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
RPC_TASK_SOFTCONN returns connection errors to the caller which allows the pNFS
file layout to quickly try the MDS or perhaps another DS.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Function rename to ensure that the functionality of nfs_unlock_request()
mirrors that of nfs_lock_request(). Then let nfs_unlock_and_release_request()
do the work of what used to be called nfs_unlock_request()...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
We only have two places where we need to grab a reference when trying
to lock the nfs_page. We're better off making that explicit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
We now hold a reference to the nfs_page across the calls to
nfs_set_page_writeback and nfs_end_page_writeback, and that
means we already have a reference to the struct page.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
We have to unlock the nfs_page before we call nfs_end_page_writeback
to avoid races with functions that expect the page to be unlocked
when PG_locked and PG_writeback are not set.
The problem is that nfs_unlock_request also releases the nfs_page,
causing a deadlock if the release of the nfs_open_context
triggers an iput() while the PG_writeback flag is still set...
The solution is to separate the unlocking and release of the nfs_page,
so that we can do the former before nfs_end_page_writeback and the
latter after.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
Move the error handling for nfs_generic_pagein() into a single function.
Ditto for nfs_generic_flush().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
These are needed when v3 and v4 are not enabled.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the allocation of nfs_write_header fails, the list of nfs_pages that
needs to be cleaned up is still on desc->pg_list...
Reported-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Fred Isaman <iisaman@netapp.com>
This also has the advantage that it allows directio to use pnfs.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Need this to pass into nfs_commitdata_init, in order to keep data->dreq
accurate.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Factors out the code that needs to change when directio
starts using these code paths.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is COMMIT that is handled the most differently between
the paged and direct paths. Create a structure that encapsulates
everything either path needs to know about the commit state.
We could use void to hide some of the layout driver stuff, but
Trond suggests pulling it out to ensure type checking, given the
huge changes being made, and the fact that it doesn't interfere
with other drivers.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Factors out the code that will need to change when directio
starts using these code paths. This will allow directio to use
the generic pagein and flush routines
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Decouple nfs_pgio_header and nfs_write_data, and have (possibly
multiple) nfs_write_datas each take a refcount on nfs_pgio_header.
For the moment keeps nfs_write_header as a way to preallocate a single
nfs_write_data with the nfs_pgio_header. The code doesn't need this,
and would be prettier without, but given the amount of churn I am
already introducing I didn't want to play with tuning new mempools.
This also fixes bug in pnfs_ld_handle_write_error. In the case of
desc->pg_bsize < PAGE_CACHE_SIZE, the pages list was empty, causing
replay attempt to do nothing.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Both nfs_read_data and nfs_write_data devote several fields which
can be combined into a single shared struct.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In order to avoid duplicating all the data in nfs_read_data whenever we
split it up into multiple RPC calls (either due to a short read result
or due to rsize < PAGE_SIZE), we split out the bits that are the same
per RPC call into a separate "header" structure.
The goal this patch moves towards is to have a single header
refcounted by several rpc_data structures. Thus, want to always refer
from rpc_data to the header, and not the other way. This patch comes
close to that ideal, but the directio code currently needs some
special casing, isolated in the nfs_direct_[read_write]hdr_release()
functions. This will be dealt with in a future patch.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Make it consistent with nfs_initiate_commit.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commits don't need the vectors of pages, etc. that writes do. Split out
a separate structure for the commit operation.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we conditionally drop the inode->i_lock when it is safe
to do so in the commit loops.
We do so after locking the nfs_page, but before removing it from the
commit list. We can then use list_safe_reset_next to recover the loop
after the lock is retaken.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The decrement is handled by each call to nfs_request_remove_commit_list,
no need to do it again in nfs_scan_commit.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move more pnfs-isms out of the generic commit code.
Bugfixes:
- filelayout_scan_commit_lists doesn't need to get/put the lseg.
In fact since it is run under the inode->i_lock, the lseg_put()
can deadlock.
- Ensure that we distinguish between what needs to be done for
commit-to-data server and what needs to be done for commit-to-MDS
using the new flag PG_COMMIT_TO_DS. Otherwise we may end up calling
put_lseg() on a bucket for a struct nfs_page that got written
through the MDS.
- Fix a case where we were using list_del() on an nfs_page->wb_list
instead of list_del_init().
- filelayout_initiate_commit needs to call filelayout_commit_release
on error instead of the mds_ops->rpc_release(). Otherwise it won't
clear the commit lock.
Cleanups:
- Let the files layout manage the commit lists for the pNFS case.
Don't expose stuff like pnfs_choose_commit_list, and the fact
that the commit buckets hold references to the layout segment
in common code.
- Cast out the put_lseg() calls for the struct nfs_read/write_data->lseg
into the pNFS layer from whence they came.
- Let the pNFS layer manage the NFS_INO_PNFS_COMMIT bit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
The radix tree is only being used to compile lists of reqs needing commit.
It is simpler to just put the reqs directly into a list.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The last real use of this tag was removed by
commit 7f2f12d963 NFS: Simplify nfs_wb_page()
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch adds a lightweight sync migrate operation MIGRATE_SYNC_LIGHT
mode that avoids writing back pages to backing storage. Async compaction
maps to MIGRATE_ASYNC while sync compaction maps to MIGRATE_SYNC_LIGHT.
For other migrate_pages users such as memory hotplug, MIGRATE_SYNC is
used.
This avoids sync compaction stalling for an excessive length of time,
particularly when copying files to a USB stick where there might be a
large number of dirty pages backed by a filesystem that does not support
->writepages.
[aarcange@redhat.com: This patch is heavily based on Andrea's work]
[akpm@linux-foundation.org: fix fs/nfs/write.c build]
[akpm@linux-foundation.org: fix fs/btrfs/disk-io.c build]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Asynchronous compaction is used when allocating transparent hugepages to
avoid blocking for long periods of time. Due to reports of stalling,
there was a debate on disabling synchronous compaction but this severely
impacted allocation success rates. Part of the reason was that many dirty
pages are skipped in asynchronous compaction by the following check;
if (PageDirty(page) && !sync &&
mapping->a_ops->migratepage != migrate_page)
rc = -EBUSY;
This skips over all mapping aops using buffer_migrate_page() even though
it is possible to migrate some of these pages without blocking. This
patch updates the ->migratepage callback with a "sync" parameter. It is
the responsibility of the callback to fail gracefully if migration would
block.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have no business doing any this in the standard write release path.
Get rid of it, and put it in the pNFS layer.
Also, while we're at it, get rid of the completely bogus unlock/relock
semantics that were present in nfs_writeback_release_full(). It is
not only unnecessary, but actually dangerous to release the write lock
just in order to take it again in nfs_page_async_flush(). Better just
to open code the pgio operations in a pnfs helper.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
When CONFIG_NFS=y and CONFIG_NFS_V3_{,V4}=n we get the following warning.
fs/nfs/write.c: In function ‘nfs_writeback_done’:
fs/nfs/write.c:1246:21: warning: unused variable ‘server’
Remove the variable 'server' to fix the above warning.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
These files were getting <linux/module.h> via an implicit include
path, but we want to crush those out of existence since they cost
time during compiles of processing thousands of lines of headers
for no reason. Give them the lightweight header that just contains
the EXPORT_SYMBOL infrastructure.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
For pnfs pagelist write failure, we need to pg_recoalesce and resend IO to
mds.
Signed-off-by: Peng Tao <peng_tao@emc.com>
Signed-off-by: Jim Rees <rees@umich.edu>
Cc: stable@kernel.org [3.0]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs_find_and_lock_request will take a reference to the nfs_page and
will then put it if the req is already locked. It's possible though
that the reference will be the last one. That put then can kick off
a whole series of reference puts:
nfs_page
nfs_open_context
dentry
inode
If the inode ends up being deleted, then the VFS will call
truncate_inode_pages. That function will try to take the page lock, but
it was already locked when migrate_page was called. The code
deadlocks.
Fix this by simply refusing the migration request if PagePrivate is
already set, indicating that the page is already associated with an
active read or write request.
We've had a customer test a backported version of this patch and
the preliminary results seem good.
Cc: stable@kernel.org
Cc: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Harshula Jayasuriya <harshula@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
commit 420e3646 allowed the kernel to reduce the number of unnecessary
commit calls by skipping the commit when there are a large number of
outstanding pages.
However, the current test in nfs_commit_unstable_pages does not handle
the edge condition properly. When ncommit == 0, then that means that the
kernel doesn't need to do anything more for the inode. The current test
though in the WB_SYNC_NONE case will return true, and the inode will end
up being marked dirty. Once that happens the inode will never be clean
until there's a WB_SYNC_ALL flush.
Fix this by immediately returning from nfs_commit_unstable_pages when
ncommit == 0.
Mike noticed this problem initially in RHEL5 (2.6.18-based kernel) which
has a backported version of 420e3646. The inode cache there was growing
very large. The inode cache was unable to be shrunk since the inodes
were all marked dirty. Calling sync() would essentially "fix" the
problem -- the WB_SYNC_ALL flush would result in the inodes all being
marked clean.
What I'm not clear on is how big a problem this is in mainline kernels
as the writeback code there is very different. Either way, it seems
incorrect to re-mark the inode dirty in this case.
Reported-by: Mike McLean <mikem@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@kernel.org [2.6.34+]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This reverts commit b80c3cb628.
The reverted commit was rendered obsolete by a VFS fix: commit
5547e8aac6 (writeback: Update dirty flags in
two steps). We now no longer need to worry about writeback_single_inode()
missing our marking the inode for COMMIT in 'do_writepages()' call.
Reverting this patch, fixes a performance regression in which the inode
would continuously get queued to the dirty list, causing the writeback
code to unnecessarily try to send a COMMIT.
Signed-off-by: Trond Myklebust <Trond.Myklebust>
Tested-by: Simon Kirby <sim@hostway.ca>
Cc: stable@kernel.org [2.6.35+]
Fix a typo which causes an Oops in the RPC layer, when using wsize < 4k.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Sricharan R <r.sricharan@ti.com>
* 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (44 commits)
NFSv4: Don't use the delegation->inode in nfs_mark_return_delegation()
nfs: don't use d_move in nfs_async_rename_done
RDMA: Increasing RPCRDMA_MAX_DATA_SEGS
SUNRPC: Replace xprt->resend and xprt->sending with a priority queue
SUNRPC: Allow caller of rpc_sleep_on() to select priority levels
SUNRPC: Support dynamic slot allocation for TCP connections
SUNRPC: Clean up the slot table allocation
SUNRPC: Initalise the struct xprt upon allocation
SUNRPC: Ensure that we grab the XPRT_LOCK before calling xprt_alloc_slot
pnfs: simplify pnfs files module autoloading
nfs: document nfsv4 sillyrename issues
NFS: Convert nfs4_set_ds_client to EXPORT_SYMBOL_GPL
SUNRPC: Convert the backchannel exports to EXPORT_SYMBOL_GPL
SUNRPC: sunrpc should not explicitly depend on NFS config options
NFS: Clean up - simplify the switch to read/write-through-MDS
NFS: Move the pnfs write code into pnfs.c
NFS: Move the pnfs read code into pnfs.c
NFS: Allow the nfs_pageio_descriptor to signal that a re-coalesce is needed
NFS: Use the nfs_pageio_descriptor->pg_bsize in the read/write request
NFS: Cache rpc_ops in struct nfs_pageio_descriptor
...
Use nfs_pageio_reset_read_mds and nfs_pageio_reset_write_mds instead of
completely reinitialising the struct nfs_pageio_descriptor.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
...and ensure that we recoalese to take into account differences in
differences in block sizes when falling back to write through the MDS.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Instead of looking up the rsize and wsize, the routines that generate the
RPC requests should really be using the pg_bsize, since that is what we
use when deciding whether or not to coalesce write requests...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Split them up into two parts: one which sets up the struct nfs_read/write_data,
the other which sets up the actual RPC call or pNFS call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we're writing back data, and the FLUSH_STABLE flag is set, then we
always want to use NFS_FILE_SYNC, since we're always in a situation where
we're doing page reclaim, and so we want to free up the page as quickly
as possible.
If we're in the FLUSH_COND_STABLE case, then we either want to use another
unstable write (if we have to do a commit anyway) or again, we want to
use NFS_FILE_SYNC because we know that we have no more pages to write
out.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ask for whole file layouts. Until support for layout segments is fully
supported in the file layout code, discard non-whole file layouts.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need to ensure that the layouts are set up before we can decide to
coalesce requests. To do so, we want to further split up the struct
nfs_pageio_descriptor operations into an initialisation callback, a
coalescing test callback, and a 'do i/o' callback.
This patch cleans up the existing callback methods before adding the
'initialisation' callback.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In current pnfs tree, all the layouts set mds_offset in their
.write_pagelist member.
mds_offset is only used by generic layer and should be handled by it.
This patch is for upstream. It is needed in this -rc series to fix a
bug in objects layout_commit.
I'll send patches for objects and blocks to be
squashed into current pnfs tree.
TODO: It looks like the read path needs the same patch.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Remove two unused struct writeback_control fields:
.encountered_congestion (completely unused)
.nonblocking (never set, checked/showed in XFS,NFS/btrfs)
The .for_background check in nfs_write_inode() is also removed btw,
as .for_background implies WB_SYNC_NONE.
Reviewed-by: Jan Kara <jack@suse.cz>
Proposed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
