glusterfs.git/xlators/features/upcall/src/upcall-internal.c, branch v3.11.0

Upcall: Fix possible memleak when inode_ctx_set fails

2017-01-12T15:47:23+00:00

In __upcall_inode_ctx_set(), if inode_ctx_set fails we should
free allocated memory for ctx. This patch takes care of the same.

Change-Id: Iafb42787151a579caf6f396c9b414ea48d16e6b4
BUG: 1412489
Reported-by: Nithya Balachandran 
Signed-off-by: Soumya Koduri 
Reviewed-on: http://review.gluster.org/16381
Reviewed-by: N Balachandran 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Jeff Darcy

upcall: Fix 'use after free' in a log message

2016-12-13T14:48:41+00:00

There is chance of accessing freed pointer in a log message at TRACE
level while cleaning up expired client entries.

Change-Id: I06b4dad755df63978ab04ca52442bfd4600d139a
BUG: 1404168
Reported-by: Ravishankar N 
Signed-off-by: Soumya Koduri 
Reviewed-on: http://review.gluster.org/16117
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Niels de Vos 
Smoke: Gluster Build System

upcall: Fix a log level

2016-11-08T20:44:47+00:00

In upcall_cache_invalidation(), the gfid can be NULL in certain
valid test cases(eg: entry for ".." in readdirp), hence change
the log level from WARNING to DEBUG.

Change-Id: Ic90167a0e2076694e9131913114460df7b939b30
BUG: 1392167
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/15777
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Smoke: Gluster Build System 
Reviewed-by: Rajesh Joseph 
Reviewed-by: Jeff Darcy

md-cache, afr: Reduce the window of stale read

2016-10-20T07:07:55+00:00

Problem:
Consider a replica setup, where one mount writes data to a
file and the other mount reads the file. In afr, read operations
are not transaction based, a brick(read subvolume) is chosen as
a part of lookup or other operations, read is always wound only
to the read subvolume, even if there was write from a different client
that failed on this brick. This stale read continues until there is
a lookup or any write operation from the mount point. Currently, this
is not a major issue, as a lookup is issued before every read and it will
switch the read subvolume to a correct one. But with the plan of
increasing md-cache timeout to 600s, the stale read problem will be
more pronounced, i.e. stale read can continue for 600s(or more if cascaded
with readdirp), as there will be no lookups.

Solution:
Afr doesn't have any built-in solution for stale read(without affecting
the performance). The solution that came up, was to use upcall. When a file
on any brick is marked bad for the first time, upcall sends a notification
to all the clients that had recently accessed the file. The solution has
2 parts:
- Identifying when a file is marked bad, on any of the bricks,
  for the first time
- Client side actions on recieving the notifications

Identifying when a file is marked bad on any of the bricks for the first time:
-----------------------------------------------------------------------------
The idea is to track xattrop in upcall. xattrop currently comes with 2 afr
xattrs - afr dirty bit and afr pending xattrs.
   Dirty xattr is set to 1 before every write, and is unset if write succeeds.
In certain scenarios, dirty xattr can be 0 and still the file could be bad
copy. Hence do not track dirty xattr.
   Pending xattr is set on the good copy, indicating the other bricks that have
bad copy. It is still not as simple as, notifying when any of the pending xattrs
change. It could lead to flood of notifcations, in case the other brick is
completely down or consistantly failing. Hence it is important to notify only
once, the first time a good copy is marked bad.

Client side actions on recieving pending xattr change, notification:
--------------------------------------------------------------------
md-cache will invalidate the cache of that file, so that further lookup is
passed down to afr and hence update the read subvolume. Invalidating only in
md-cache is not enough, consider the folling oder of opertaions:
- pending xattr invalidation - invalidate md-cache
- readdirp on the bad read subvolume - fill md-cache
- lookup (served from md-cache)
- read - wound to the old read subvol.
Hence, along with invalidating md-cache, it is very important to reset the
read subvolume for that file, in afr.

Design Credit: Anuradha Talur, Ravishankar N

1. xattrop doesn't carry info saying post op/pre op.
2. Pre xattrop will have 0 value for all pending xattrs,
   the cbk of pre xattrop carries the on-disk xattr value.
   Non zero indicated healing is required.
3. Post xattrop will have non zero value for any of the
   pending xattrs, if the fop failed on any of the bricks.

Change-Id: I469cbc111714c433984fe1c922be2ef113c25804
BUG: 1211863
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/15398
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: Pranith Kumar Karampuri 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

xlators/upcall: fix unused variable warnings/errors

2016-09-13T16:50:21+00:00

http://review.gluster.org/14085 fixes a "pragma leak" where the
generated rpc/xdr headers have a pair of pragmas that disable these
warnings. With the warnings disabled, many unused variables have
crept into the code base.

And 14085 won't pass its own smoke test until all these warnings are
fixed.

BUG: 1369124
Change-Id: I48c0d9bbf13ccf79975dd7b35d524f6d7428ac52
Signed-off-by: Kaleb S. KEITHLEY 
Reviewed-on: http://review.gluster.org/15484
Reviewed-by: Niels de Vos 
NetBSD-regression: NetBSD Build System 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System

md-cache: Register the list of xattrs with cache-invalidation

2016-08-31T06:07:01+00:00

Issue:
md-cache caches a specified list of xattrs, and when cache invalidation
is enabled, it makes sense to recieve invalidation only when those xattrs
are modified by other clients. But the current implementation of upcall
is that, it will send invalidation when any of the on-disk xattrs is modified.

Solution:
md-cache sends a list of xattrs that it is interested in, to upcall by
issuing an ipc(). The challenge here is to make sure everytime a brick
goes offline and comes back up, the ipc() needs to be issued to the
bricks. Hence ipc() is sent from md-cache every time there is a
CHILD_UP/CHILD_MODIFIED event.

TODO:
There will be patches following, in cluster xlators, to implement ipc fop.

Change-Id: I6efcf3df474f5ce6eabd3d6694c00c7bd89bc25d
BUG: 1211863
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/15002
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Rajesh Joseph 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Prashanth Pai 
Reviewed-by: Raghavendra G

upcall: fix unused variable warnings/errors

2016-08-25T12:11:31+00:00

http://review.gluster.org/14085 fixes a/the "leak" - via the
generated rpc/xdr headers - of pragmas that mask these warnings.

However 14085 won't pass the smoke test until all the warnings are
fixed.

Change-Id: I887aa033f00ab67f73c7d7a7f1b3054d43bffc49
BUG: 1369124
Signed-off-by: Kaleb S. KEITHLEY 
Reviewed-on: http://review.gluster.org/15252
Reviewed-by: Niels de Vos 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

upcall: pass dict with xattrs on xattr invalidation

2016-05-19T09:28:07+00:00

In case of xattr invalidation, return a dict containing
the updated xattrs.

[ndevos: move chunks to change 12995 and only address the xattrs-dict here]

Change-Id: I8733f06a519a9a0f24be1bb4b2c38c9c9dce0ce2
BUG: 1211863
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/12996
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Niels de Vos 
Reviewed-by: soumya k 
Tested-by: soumya k

upcall: Add support to invalidate xattrs

2016-05-11T18:23:00+00:00

When SElinux is used, clients should get a notification that the
extended attributes have been updated. Other components (like md-cache)
will be able to use this too.

A big part of the implementation comes from Poornima through the first
version of http://review.gluster.org/12996.

Also moving the flags from upcall-cache-invalidation.h to the main
libglusterfs upcall-utils.h file, so that other places can easily use
them in future.

Change-Id: I525345bed8f22d029524ff19ccaf726a2c905454
BUG: 1211863
Signed-off-by: Niels de Vos 
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/12995
Reviewed-by: soumya k 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

Upcall: Read gfid from iatt in case of invalid inode

2015-12-01T10:32:50+00:00

When any file/dir is looked upon for the first time, inode
created shall be invalid till it gets linked to the inode table.
In such cases, read the gfid from the iatt structure returned
as part of such fops for UPCALL processing.

Change-Id: Ie5eb2f3be18c34cf7ef172e126c9db5ef7a8512b
BUG: 1283983
Signed-off-by: Soumya Koduri 
Reviewed-on: http://review.gluster.org/12773
Reviewed-by: Kaleb KEITHLEY 
Tested-by: NetBSD Build System 
Tested-by: Gluster Build System 
Reviewed-by: Niels de Vos