rds: Changing IP address internal representation to struct in6_addr

This patch changes the internal representation of an IP address to use
struct in6_addr. IPv4 address is stored as an IPv4 mapped address.
All the functions which take an IP address as argument are also
changed to use struct in6_addr. But RDS socket layer is not modified
such that it still does not accept IPv6 address from an application.
And RDS layer does not accept nor initiate IPv6 connections.

v2: Fixed sparse warnings.

Signed-off-by: Ka-Cheong Poon <ka-cheong.poon@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rds: clean up loopback rds_connections on netns deletion

The RDS core module creates rds_connections based on callbacks
from rds_loop_transport when sending/receiving packets to local
addresses.

These connections will need to be cleaned up when they are
created from a netns that is not init_net, and that netns is deleted.

Add the changes aligned with the changes from
commit ebeeb1ad9b8a ("rds: tcp: use rds_destroy_pending() to synchronize
netns/module teardown and rds connection/workq management") for
rds_loop_transport

Reported-and-tested-by: syzbot+4c20b3866171ce8441d2@syzkaller.appspotmail.com
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rds: avoid unenecessary cong_update in loop transport

Loop transport which is self loopback, remote port congestion
update isn't relevant. Infact the xmit path already ignores it.
Receive path needs to do the same.

Reported-by: syzbot+4c20b3866171ce8441d2@syzkaller.appspotmail.com
Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: TCP: Hooks to set up a single connection path

This patch adds ->conn_path_connect callbacks in the rds_transport
that are used to set up a single connection path.

Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: TCP: make receive path use the rds_conn_path

The ->sk_user_data contains a pointer to the rds_conn_path
for the socket. Use this consistently in the rds_tcp_data_ready
callbacks to get the rds_conn_path for rds_recv_incoming.

Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: Rework path specific indirections

Refactor code to avoid separate indirections for single-path
and multipath transports. All transports (both single and mp-capable)
will get a pointer to the rds_conn_path, and can trivially derive
the rds_connection from the ->cp_conn.

Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rds: fix coding style issues

Fix coding style issues in the following files:

ib_cm.c: add space
loop.c: convert spaces to tabs
sysctl.c: add space
tcp.h: convert spaces to tabs
tcp_connect.c:remove extra indentation in switch statement
tcp_recv.c: convert spaces to tabs
tcp_send.c: convert spaces to tabs
transport.c: move brace up one line on for statement

Signed-off-by: Joshua Houghton <josh@awful.name>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: split out connection specific state from rds_connection to rds_conn_path

In preparation for multipath RDS, split the rds_connection
structure into a base structure, and a per-path struct rds_conn_path.
The base structure tracks information and locks common to all
paths. The workqs for send/recv/shutdown etc are tracked per
rds_conn_path. Thus the workq callbacks now work with rds_conn_path.

This commit allows for one rds_conn_path per rds_connection, and will
be extended into multiple conn_paths in subsequent commits.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: use gfp flags from caller in conn_alloc()

We should be using the gfp flags the caller specified here, instead of
GFP_KERNEL. I think this might be a bugfix, depending on the value of
"sock->sk->sk_allocation" when we call rds_conn_create_outgoing() in
rds_sendmsg(). Otherwise, it's just a cleanup.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rds: remove the second argument of k[un]map_atomic()

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>

rds: prevent BUG_ON triggering on congestion map updates

Recently had this bug halt reported to me:

kernel BUG at net/rds/send.c:329!
Oops: Exception in kernel mode, sig: 5 [#1]
SMP NR_CPUS=1024 NUMA pSeries
Modules linked in: rds sunrpc ipv6 dm_mirror dm_region_hash dm_log ibmveth sg
ext4 jbd2 mbcache sd_mod crc_t10dif ibmvscsic scsi_transport_srp scsi_tgt
dm_mod [last unloaded: scsi_wait_scan]
NIP: d000000003ca68f4 LR: d000000003ca67fc CTR: d000000003ca8770
REGS: c000000175cab980 TRAP: 0700 Not tainted (2.6.32-118.el6.ppc64)
MSR: 8000000000029032 <EE,ME,CE,IR,DR> CR: 44000022 XER: 00000000
TASK = c00000017586ec90[1896] 'krdsd' THREAD: c000000175ca8000 CPU: 0
GPR00: 0000000000000150 c000000175cabc00 d000000003cb7340 0000000000002030
GPR04: ffffffffffffffff 0000000000000030 0000000000000000 0000000000000030
GPR08: 0000000000000001 0000000000000001 c0000001756b1e30 0000000000010000
GPR12: d000000003caac90 c000000000fa2500 c0000001742b2858 c0000001742b2a00
GPR16: c0000001742b2a08 c0000001742b2820 0000000000000001 0000000000000001
GPR20: 0000000000000040 c0000001742b2814 c000000175cabc70 0800000000000000
GPR24: 0000000000000004 0200000000000000 0000000000000000 c0000001742b2860
GPR28: 0000000000000000 c0000001756b1c80 d000000003cb68e8 c0000001742b27b8
NIP [d000000003ca68f4] .rds_send_xmit+0x4c4/0x8a0 [rds]
LR [d000000003ca67fc] .rds_send_xmit+0x3cc/0x8a0 [rds]
Call Trace:
[c000000175cabc00] [d000000003ca67fc] .rds_send_xmit+0x3cc/0x8a0 [rds]
(unreliable)
[c000000175cabd30] [d000000003ca7e64] .rds_send_worker+0x54/0x100 [rds]
[c000000175cabdb0] [c0000000000b475c] .worker_thread+0x1dc/0x3c0
[c000000175cabed0] [c0000000000baa9c] .kthread+0xbc/0xd0
[c000000175cabf90] [c000000000032114] .kernel_thread+0x54/0x70
Instruction dump:
4bfffd50 60000000 60000000 39080001 935f004c f91f0040 41820024 813d017c
7d094a78 7d290074 7929d182 394a0020 <0b090000> 40e2ff68 4bffffa4 39200000
Kernel panic - not syncing: Fatal exception
Call Trace:
[c000000175cab560] [c000000000012e04] .show_stack+0x74/0x1c0 (unreliable)
[c000000175cab610] [c0000000005a365c] .panic+0x80/0x1b4
[c000000175cab6a0] [c00000000002fbcc] .die+0x21c/0x2a0
[c000000175cab750] [c000000000030000] ._exception+0x110/0x220
[c000000175cab910] [c000000000004b9c] program_check_common+0x11c/0x180

Signed-off-by: David S. Miller <davem@davemloft.net>

rds: Lost locking in loop connection freeing

The conn is removed from list in there and this requires
proper lock protection.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: Stop supporting old cong map sending method

We now ask the transport to give us a rm for the congestion
map, and then we handle it normally. Previously, the
transport defined a function that we would call to send
a congestion map.

Convert TCP and loop transports to new cong map method.

Signed-off-by: Andy Grover <andy.grover@oracle.com>

RDS: Move loop-only function to loop.c

Also, try to better-document the locking around the
rm and its m_inc in loop.c.

Signed-off-by: Andy Grover <andy.grover@oracle.com>

RDS: inc_purge() transport function unused - remove it

Signed-off-by: Andy Grover <andy.grover@oracle.com>

RDS: cleanup: remove "== NULL"s and "!= NULL"s in ptr comparisons

Favor "if (foo)" style over "if (foo != NULL)".

Signed-off-by: Andy Grover <andy.grover@oracle.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

RDS: Fix congestion issues for loopback

We have two kinds of loopback: software (via loop transport)
and hardware (via IB). sw is used for 127.0.0.1, and doesn't
support rdma ops. hw is used for sends to local device IPs,
and supports rdma. Both are used in different cases.

For both of these, when there is a congestion map update, we
want to call rds_cong_map_updated() but not actually send
anything -- since loopback local and foreign congestion maps
point to the same spot, they're already in sync.

The old code never called sw loop's xmit_cong_map(),so
rds_cong_map_updated() wasn't being called for it. sw loop
ports would not work right with the congestion monitor.

Fixing that meant that hw loopback now would send congestion maps
to itself. This is also undesirable (racy), so we check for this
case in the ib-specific xmit code.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RDS: loopback

A simple rds transport to handle loopback connections.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>