glusterfs-snapshot.git/api/src, branch gluster-snap

libgfapi: Remove useless call to lstat

2014-01-25T07:46:48+00:00

There's no need to lstat cmd_args->volfile, since we already
check to see if fopen fails. The error message was largely the
same.

BUG: 789278
CID: 1124869

Change-Id: I10827154b32c72d2e4a1ab0d3c1e464f8af6ffee
Signed-off-by: Jose A. Rivera 
Reviewed-on: http://review.gluster.org/6783
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

libgfapi: Fix pointer dereference before NULL check

2014-01-25T07:46:35+00:00

ctx is not checked for NULL before it is dereferenced, though the
check in "err" seems to suggest we should guard against it.

BUG: 789278
CID: 1124827

Change-Id: I6ed0b42992af5f370cce9aa2feb56811cdd54b42
Signed-off-by: Jose A. Rivera 
Reviewed-on: http://review.gluster.org/6782
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

libgfapi: Fix pointer dereference before NULL check

2014-01-24T09:41:59+00:00

Call to dict_keys_join dereferences xattr before it is checked
for NULL. Restructured the function to check for NULL earlier and
call dict_unref only when needed.

BUG: 789278
CID: 1124826

Change-Id: I732fa304ad6f3b921c589832d13f73bbd36f589c
Signed-off-by: Jose A. Rivera 
Reviewed-on: http://review.gluster.org/6763
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

syncop: Change return value of syncop

2014-01-20T07:05:15+00:00

Problem:
We found a day-1 bug when syncop_xxx() infra is used inside a synctask with
compilation optimization (CFLAGS -O2).

Detailed explanation of the Root cause:
We found the bug in 'gf_defrag_migrate_data' in rebalance operation:

Lets look at interesting parts of the function:

int
gf_defrag_migrate_data (xlator_t *this, gf_defrag_info_t *defrag, loc_t *loc,
                        dict_t *migrate_data)
{
.....
code section - [ Loop ]
        while ((ret = syncop_readdirp (this, fd, 131072, offset, NULL,
                                       &entries)) != 0) {
.....
code section - [ ERRNO-1 ] (errno of readdirp is stored in readdir_operrno by a
thread)
                /* Need to keep track of ENOENT errno, that means, there is no
                   need to send more readdirp() */
                readdir_operrno = errno;
.....
code section - [ SYNCOP-1 ] (syncop_getxattr is called by a thread)
                        ret = syncop_getxattr (this, &entry_loc, &dict,
                                               GF_XATTR_LINKINFO_KEY);
code section - [ ERRNO-2]   (checking for failures of syncop_getxattr(). This
may not always be executed in same thread which executed [SYNCOP-1])
                        if (ret < 0) {
                                if (errno != ENODATA) {
                                        loglevel = GF_LOG_ERROR;
                                        defrag->total_failures += 1;
.....
}

the function above could be executed by thread(t1) till [SYNCOP-1] and code
from [ERRNO-2] can be executed by a different thread(t2) because of the way
syncop-infra schedules the tasks.

when the code is compiled with -O2 optimization this is the assembly code that
is generated:
 [ERRNO-1]
1165                        readdir_operrno = errno; <<---- errno gets expanded
as *(__errno_location())
   0x00007fd149d48b60 <+496>:        callq  0x7fd149d410c0 
   0x00007fd149d48b72 <+514>:        mov    %rax,0x50(%rsp) <<------ Address
returned by __errno_location() is stored in a special location in stack for
later use.
   0x00007fd149d48b77 <+519>:        mov    (%rax),%eax
   0x00007fd149d48b79 <+521>:        mov    %eax,0x78(%rsp)
....
 [ERRNO-2]
1281                                        if (errno != ENODATA) {
   0x00007fd149d492ae <+2366>:        mov    0x50(%rsp),%rax <<-----  Because
it already stored the address returned by __errno_location(), it just
dereferences the address to get the errno value. BUT THIS CODE NEED NOT BE
EXECUTED BY SAME THREAD!!!
   0x00007fd149d492b3 <+2371>:        mov    $0x9,%ebp
   0x00007fd149d492b8 <+2376>:        mov    (%rax),%edi
   0x00007fd149d492ba <+2378>:        cmp    $0x3d,%edi

The problem is that __errno_location() value of t1 and t2 are different. So
[ERRNO-2] ends up reading errno of t1 instead of errno of t2 even though t2 is
executing [ERRNO-2] code section.

When code is compiled without any optimization for [ERRNO-2]:
1281                                        if (errno != ENODATA) {
   0x00007fd58e7a326f <+2237>:        callq  0x7fd58e797300
<<--- As it is calling __errno_location() again it gets the
location from t2 so it works as intended.
   0x00007fd58e7a3274 <+2242>:        mov    (%rax),%eax
   0x00007fd58e7a3276 <+2244>:        cmp    $0x3d,%eax
   0x00007fd58e7a3279 <+2247>:        je     0x7fd58e7a32a1


Fix:
Make syncop_xxx() return (-errno) value as the return value in
case of errors and all the functions which make syncop_xxx() will need to use
(-ret) to figure out the reason for failure in case of syncop_xxx() failures.

Change-Id: I314d20dabe55d3e62ff66f3b4adb1cac2eaebb57
BUG: 1040356
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/6475
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

build: Start using library versioning for various libraries

2014-01-18T16:51:14+00:00

According to libtool three individual numbers stand for
CURRENT:REVISION:AGE, or C:R:A for short. The libtool
script typically tacks these three numbers onto the end
of the name of the .so file it creates. The formula for
calculating the file numbers on Linux and Solaris is

   /path/to/library/.(C - A).(A).(R)

As you release new versions of your library, you will
update the library's C:R:A. Although the rules for changing
these version numbers can quickly become confusing, a few
simple tips should help keep you on track. The libtool
documentation goes into greater depth.

In essence, every time you make a change to the library and
release it, the C:R:A should change. A new library should start
with 0:0:0. Each time you change the public interface
(i.e., your installed header files), you should increment the
CURRENT number. This is called your interface number. The main
use of this interface number is to tag successive revisions
of your API.

The AGE number is how many consecutive versions of the API the
current implementation supports. Thus if the CURRENT library
API is the sixth published version of the interface and it is
also binary compatible with the fourth and fifth versions
(i.e., the last two), the C:R:A might be 6:0:2. When you break
binary compatibility, you need to set AGE to 0 and of course
increment CURRENT.

The REVISION marks a change in the source code of the library
that doesn't affect the interface-for example, a minor bug fix.
Anytime you increment CURRENT, you should set REVISION back to 0.

Change-Id: Id72e74c1642c804fea6f93ec109135c7c16f1810
BUG: 862082
Signed-off-by: Harshavardhana 
Reviewed-on: http://review.gluster.org/5645
Tested-by: Gluster Build System 
Reviewed-by: Niels de Vos 
Reviewed-by: Vijay Bellur

libgfapi: Fixing possible dereferencing of null pointer "glfd"

2014-01-16T08:58:49+00:00

Fix: Putting a check so that pointer derefrence does not happen
when "gfld" is null

Change-Id: I281b10be445bbeec3a2728fc139d5ac94372e5b6
BUG: 789278
Signed-off-by: Lalatendu Mohanty 
Reviewed-on: http://review.gluster.org/6697
Tested-by: Gluster Build System 
Reviewed-by: Shyamsundar Ranganathan 
Reviewed-by: Vijay Bellur

libgfapi : Fixing some NULL pointer dereferencing issues.

2014-01-10T06:45:05+00:00

1. Fixing dereferencing null pointer "gio"
2. Checking "frame" before calling STACK_DESTROY (frame->root)

Change-Id: If2ce8804a8e9f3f99f71a8c0d13900afb5635072
Signed-off-by: Lalatendu Mohanty 
Reviewed-on: http://review.gluster.org/6313
Reviewed-by: Santosh Pradhan 
Tested-by: Gluster Build System 
Reviewed-by: Shyamsundar Ranganathan 
Reviewed-by: Raghavendra Talur 
Reviewed-by: Vijay Bellur

gfapi: Closed the logfile fd and initialize to NULL in glfs_fini

2013-12-26T11:16:30+00:00

Currently if logfile is closed and other threads call gf_log
after glfs_fini() is executed, it may lead to memory corruption.
Adding gf_log_fini() which closes the logfile and initializes
the logfile to NULL, thus any further logging happens to stderr.
Also added gf_log_globals_fini() which should be filled in the
future to release all the logging resources.

Change-Id: I879163e1a3636e65300d166f782517ee773cab65
BUG: 1030228
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/6552
Reviewed-by: Pranith Kumar Karampuri 
Reviewed-by: Shyamsundar Ranganathan 
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

gfapi: add THROW [(attribute) ((nothrow))] to fn decls for C++ users.

2013-12-03T18:01:59+00:00

Off hand I don't know of anything written in C++ that is or could be a user
of gfapi.

Never the less, it's possible that one could exist, or be written, and
marking the library entry points is a) friendly, b) possibly allows the
C++ compiler to generate better code, and c) is a good practice when
writing APIs that might be consumed by C++ applications. Considering we
already take the first step and use __BEGIN_DECLS/__END_DECLS to be C++
friendly, we should take the extra step

Change-Id: Ib319ecaa452a46f258a9c6e8c7221454d2fefd0f
Signed-off-by: Kaleb S. KEITHLEY 
Reviewed-on: http://review.gluster.org/6393
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

syncops: expose @flags in syncop_rmdir()

2013-11-21T21:08:32+00:00

Change-Id: I9b73c1db728e4cb3948fc118cceb292b21d48b96
BUG: 1021686
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/6112
Reviewed-by: Amar Tumballi 
Tested-by: Gluster Build System

glusterfs-snapshot.git/api/src, branch gluster-snap

libgfapi: Remove useless call to lstat

libgfapi: Fix pointer dereference before NULL check

libgfapi: Fix pointer dereference before NULL check

syncop: Change return value of syncop

build: Start using library versioning for various libraries

libgfapi: Fixing possible dereferencing of null pointer "glfd"

libgfapi : Fixing some NULL pointer dereferencing issues.

gfapi: Closed the logfile fd and initialize to NULL in glfs_fini

gfapi: add __THROW [(__attribute) ((__nothrow__))] to fn decls for C++ users.

syncops: expose @flags in syncop_rmdir()

gfapi: add THROW [(attribute) ((nothrow))] to fn decls for C++ users.