glusterfs.git/libglusterfs/src/fd.c, branch v3.3.0qa35

libglusterfs/fd: ref fds while copying the fdentries.

2012-03-26T22:09:20+00:00

Change-Id: I8973ec5d9858adfbdd6efc7cd596cf5d5af0e3cb
BUG: 767862
Signed-off-by: Raghavendra G 
Reviewed-on: http://review.gluster.com/3006
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

libglusterfs/fd: fixed fd_anonymous() leak

2012-03-07T18:39:50+00:00

fd was getting leaked whenever there was a overlapping operations,
which caused memory leak, and process fd leaks, which made most of
the operations on NFS mount of a replicate volume not work. With
the fix, things are back to normal.

Change-Id: I2d2158b2972ba5dae270d6ff7b1a827403653c04
Signed-off-by: Amar Tumballi 
BUG: 787368
Reviewed-on: http://review.gluster.com/2892
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

fuse-bridge: Handle graph-switch.

2012-02-21T09:05:14+00:00

The purpose of this patch is to let protocol/client know when its transports can
be disconnected, without application running on gluster mount noticing any
effects of graph switch.

In order to do this, we migrate all fds and blocked locks to new graph.
Once this migration is complete and there are no in-transit frames as viewed
by fuse-bridge, we send a PARENT_DOWN event to its children. protocol/client
on receiving this event, can disconnect up its transports.

Change-Id: Idcea4bc43e23fb077ac16538b61335ebad84ba16
BUG: 767862
Reviewed-on: http://review.gluster.com/2734
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

NLM - Network Lock Manger V4

2012-02-20T15:26:51+00:00

Change-Id: Ic31b8bb10a28408da2a623f4ecc0c60af01c64af
BUG: 795421
Signed-off-by: Krishna Srinivas 
Reviewed-on: http://review.gluster.com/2711
Tested-by: Gluster Build System 
Reviewed-by: Amar Tumballi

protocol/client,server: fcntl lock self healing.

2012-02-20T12:45:31+00:00

Currently(with out this patch), on a disconnect the server cleans up
the transport which inturn closes the fd's and releases the locks acquired on
those fd's by that client. On a reconnect, client just reopens the fd's but
doesn't reacquire the locks. The application that had previously acquired
the locks still is under the assumption that it is the owner of those locks
which might have been granted to other clients(if they request) by the server
leading to data corruption.

This patch allows the client to reacquire the fcntl locks (held on the fd's)
during client-server handshake.

* The server identifies the client via process-uuid-xl (which is a combination
  of uuid and client-protocol name, it is assumed to be unique) and lk-version
  number.

* The client maintains a list of process-uuid-xl, lk-version pair for each
  accepted connection. On a connect, the server traverses the list for a
  matching pair, if a matching pair is not found the the server returns
  lk-version with value 0, else it returns the lk-version it has in store.

* On a disconnect, the server and client enter grace period, and on the
  completion of the grace period, the client bumps up its lk-version number
  (which means, it will reacquire the locks the next time) and the server will
  distroy the connection. If reconnection happens within the grace period, the
  server will find the matching (process-uuid-xl, lk-version) pair in its list
  which guarantees that the fd's and there corresponding locks are still valid
  for this client.

Configurable options:
  To set grace-timeout, the following options are
    option server.grace-timeout value
    option client.grace-timeout value

  To enable or disable the lk-heal,
    option lk-heal [on|off]

gluster volume set command can be used to configurable options
Change-Id: Id677ef1087b300d649f278b8b2aa0d94eae85ed2
BUG: 795386
Signed-off-by: Mohammed Junaid 
Reviewed-on: http://review.gluster.com/2766
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

cli: Extend "volume status" with statedump info

2012-01-27T12:20:04+00:00

This patch enhances and extends the "volume status" command with information
obtained from the statedump of the bricks of volumes.

Adds new status types : clients, inode, fd, mem, callpool
The new syntax of "volume status" is,
 #gluster volume status [all|{ []
                         [misc-details|clients|inode|fd|mem|callpool]}]

Change-Id: I8d019718465bbc3de727653a839de7238f45da5c
BUG: 765495
Signed-off-by: Kaushal M 
Reviewed-on: http://review.gluster.com/2637
Tested-by: Gluster Build System 
Reviewed-by: Krishnan Parthasarathi

core: GFID filehandle based backend and anonymous FDs

2012-01-20T13:03:42+00:00

1. What
--------
This change introduces an infrastructure change in the filesystem
which lets filesystem operation address objects (inodes) just by its
GFID. Thus far GFID has been a unique identifier of a user-visible
inode. But in terms of addressability the only mechanism thus far has
been the backend filesystem path, which could be derived from the
GFID only if it was cached in the inode table along with the entire set
of dentry ancestry leading up to the root.

This change essentially decouples addressability from the namespace. It
is no more necessary to be aware of the parent directory to address a
file or directory.

2. Why
-------
The biggest use case for such a feature is NFS for generating
persistent filehandles. So far the technique for generating filehandles
in NFS has been to encode path components so that the appropriate
inode_t can be repopulated into the inode table by means of a recursive
lookup of each component top-down.

Another use case is the ability to perform more intelligent self-healing
and rebalancing of inodes with hardlinks and also to detect renames.

A derived feature from GFID filehandles is anonymous FDs. An anonymous FD
is an internal USABLE "fd_t" which does not map to a user opened file
descriptor or to an internal ->open()'d fd. The ability to address a file
by the GFID eliminates the need to have a persistent ->open()'d fd for the
purpose of avoiding the namespace. This improves NFS read/write performance
significantly eliminating open/close calls and also fixes some of today's
limitations (like keeping an FD open longer than necessary resulting
in disk space leakage)

3. How
-------

At each storage/posix translator level, every file is hardlinked inside
a hidden .glusterfs directory (under the top level export) with the name
as the ascii-encoded standard UUID format string. For reasons of performance
and scalability there is a two-tier classification of those hardlinks
under directories with the initial parts of the UUID string as the directory
names.

For directories (which cannot be hardlinked), the approach is to use a symlink
which dereferences the parent GFID path along with basename of the directory.
The parent GFID dereference will in turn be a dereference of the grandparent
with the parent's basename, and so on recursively up to the root export.

4. Development
---------------

4a. To leverage the ability to address an inode by its GFID, the technique is
to perform a "nameless lookup". This means, to populate a loc_t structure as:

loc_t {
   pargfid: NULL
   parent: NULL
   name: NULL
   path: NULL
   gfid: GFID to be looked up [out parameter]
   inode: inode_new () result [in parameter]
}

and performing such lookup will return in its callback an inode_t
populated with the right contexts and a struct iatt which can be
used to perform an inode_link () on the inode (without a parent and
basename). The inode will now be hashed and linked in the inode table
and findable via inode_find().

A fundamental change moving forward is that the primary fields in a
loc_t structure are now going to be (pargfid, name) and (gfid) depending
on the kind of FOP. So far path had been the primary field for operations.
The remaining fields only serve as hints/helpers.

4b. If read/write is to be performed on an inode_t, the approach so far
has been to: fd_create(), STACK_WIND(open, fd), fd_bind (in callback) and
then perform STACK_WIND(read, fd) etc. With anonymous fds now you can do
fd_anonymous (inode), STACK_WIND (read, fd). This results in great boost
in performance in the inbuilt NFS server.

5. Misc
-------
The inode_ctx_put[2] has been renamed to inode_ctx_set[2] to be consistent
with the rest of the codebase.

Change-Id: Ie4629edf6bd32a595f4d7f01e90c0a01f16fb12f
BUG: 781318
Reviewed-on: http://review.gluster.com/669
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

glusterfs: An effort to fix all the spell mistakes and typo

2011-11-17T05:08:56+00:00

in the entire glusterfs codebase.

This patch fixes many of spell mistakes and typo in the entire
glusterfs codebase and all supported modules.

Change-Id: I83238a41aa08118df3cf4d1d605505dd3cda35a1
BUG: 3809
Signed-off-by: Harshavardhana 
Reviewed-on: http://review.gluster.com/731
Tested-by: Gluster Build System 
Reviewed-by: Amar Tumballi 
Reviewed-by: Vijay Bellur

statedump: do not print the inode number in the statedump

2011-10-01T12:55:22+00:00

    Since gfid is used to uniquely identify a inode, in the statedump
    printing inode number is not necessary. Its suffecient if the gfid
    of the inode is printed. And do not print the the inodelks, entrylks
    and posixlks if the lock count is 0.

Change-Id: Idac115fbce3a5684a0f02f8f5f20b194df8fb27f
BUG: 3476
Reviewed-on: http://review.gluster.com/530
Tested-by: Gluster Build System 
Reviewed-by: Amar Tumballi

Eliminate many "var set but not used" warnings with newer gcc.

2011-09-08T06:48:01+00:00

This fixes ~200 such warnings, but leaves three categories untouched.

(1) Rpcgen code.

(2) Macros which set variables in the outer (calling function) scope.

(3) Variables which are set via function calls which may have side effects.

Change-Id: I6554555f78ed26134251504b038da7e94adacbcd
BUG: 2550
Reviewed-on: http://review.gluster.com/371
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati