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Commit Graph

35 Commits

Author SHA1 Message Date
Mel Gorman
c76562b670 netvm: prevent a stream-specific deadlock
This patch series is based on top of "Swap-over-NBD without deadlocking
v15" as it depends on the same reservation of PF_MEMALLOC reserves logic.

When a user or administrator requires swap for their application, they
create a swap partition and file, format it with mkswap and activate it
with swapon.  In diskless systems this is not an option so if swap if
required then swapping over the network is considered.  The two likely
scenarios are when blade servers are used as part of a cluster where the
form factor or maintenance costs do not allow the use of disks and thin
clients.

The Linux Terminal Server Project recommends the use of the Network Block
Device (NBD) for swap but this is not always an option.  There is no
guarantee that the network attached storage (NAS) device is running Linux
or supports NBD.  However, it is likely that it supports NFS so there are
users that want support for swapping over NFS despite any performance
concern.  Some distributions currently carry patches that support swapping
over NFS but it would be preferable to support it in the mainline kernel.

Patch 1 avoids a stream-specific deadlock that potentially affects TCP.

Patch 2 is a small modification to SELinux to avoid using PFMEMALLOC
	reserves.

Patch 3 adds three helpers for filesystems to handle swap cache pages.
	For example, page_file_mapping() returns page->mapping for
	file-backed pages and the address_space of the underlying
	swap file for swap cache pages.

Patch 4 adds two address_space_operations to allow a filesystem
	to pin all metadata relevant to a swapfile in memory. Upon
	successful activation, the swapfile is marked SWP_FILE and
	the address space operation ->direct_IO is used for writing
	and ->readpage for reading in swap pages.

Patch 5 notes that patch 3 is bolting
	filesystem-specific-swapfile-support onto the side and that
	the default handlers have different information to what
	is available to the filesystem. This patch refactors the
	code so that there are generic handlers for each of the new
	address_space operations.

Patch 6 adds an API to allow a vector of kernel addresses to be
	translated to struct pages and pinned for IO.

Patch 7 adds support for using highmem pages for swap by kmapping
	the pages before calling the direct_IO handler.

Patch 8 updates NFS to use the helpers from patch 3 where necessary.

Patch 9 avoids setting PF_private on PG_swapcache pages within NFS.

Patch 10 implements the new swapfile-related address_space operations
	for NFS and teaches the direct IO handler how to manage
	kernel addresses.

Patch 11 prevents page allocator recursions in NFS by using GFP_NOIO
	where appropriate.

Patch 12 fixes a NULL pointer dereference that occurs when using
	swap-over-NFS.

With the patches applied, it is possible to mount a swapfile that is on an
NFS filesystem.  Swap performance is not great with a swap stress test
taking roughly twice as long to complete than if the swap device was
backed by NBD.

This patch: netvm: prevent a stream-specific deadlock

It could happen that all !SOCK_MEMALLOC sockets have buffered so much data
that we're over the global rmem limit.  This will prevent SOCK_MEMALLOC
buffers from receiving data, which will prevent userspace from running,
which is needed to reduce the buffered data.

Fix this by exempting the SOCK_MEMALLOC sockets from the rmem limit.  Once
this change it applied, it is important that sockets that set
SOCK_MEMALLOC do not clear the flag until the socket is being torn down.
If this happens, a warning is generated and the tokens reclaimed to avoid
accounting errors until the bug is fixed.

[davem@davemloft.net: Warning about clearing SOCK_MEMALLOC]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:47 -07:00
Sjur Brændeland
eaa8c5f3cf caif: Clear shutdown mask to zero at reconnect.
Clear caif sockets's shutdown mask at (re)connect.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-25 16:07:22 -07:00
Joe Perches
e87cc4728f net: Convert net_ratelimit uses to net_<level>_ratelimited
Standardize the net core ratelimited logging functions.

Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-15 13:45:03 -04:00
Eric Dumazet
95c9617472 net: cleanup unsigned to unsigned int
Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 12:44:40 -04:00
Dmitry Tarnyagin
447648128e caif: set traffic class for caif packets
Set traffic class for CAIF packets, based on socket
priority, CAIF protocol type, or type of message.

Traffic class mapping for different packet types:
 - control:       TC_PRIO_CONTROL;
 - flow control:  TC_PRIO_CONTROL;
 - at:            TC_PRIO_CONTROL;
 - rfm:           TC_PRIO_INTERACTIVE_BULK;
 - other sockets: equals to socket's TC;
 - network data:  no change.

Signed-off-by: Dmitry Tarnyagin <dmitry.tarnyagin@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-13 11:37:36 -04:00
David S. Miller
dd48dc34fe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-02-04 16:39:32 -05:00
sjur.brandeland@stericsson.com
4a695823b5 caif: Kill debugfs vars for caif socket
Kill off the debug-fs exposed varaibles from caif_socket.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-04 16:06:27 -05:00
Dmitry Tarnyagin
ba7605745d caif: Bugfix double kfree_skb upon xmit failure
SKB is freed twice upon send error. The Network stack consumes SKB even
when it returns error code.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-02 14:35:12 -05:00
sjur.brandeland@stericsson.com
54e90fb5ca caif: Fixes freeze on Link layer removal.
CAIF Socket layer - caif_socket.c:
- Plug mem-leak at reconnect.
- Always call disconnect to cleanup CAIF stack.
- Disconnect will always report success.

CAIF configuration layer - cfcnfg.c
- Disconnect must dismantle the caif stack correctly
- Protect against faulty removals (check on id zero)

CAIF mux layer - cfmuxl.c
- When inserting new service layer in the MUX remove
  any old entries with the same ID.
- When removing CAIF Link layer, remove the associated
  service layers before notifying service layers.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-22 20:11:47 -04:00
sjur.brandeland@stericsson.com
3f874adc4a caif: remove unesesarry exports
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-15 17:45:56 -04:00
sjur.brandeland@stericsson.com
33b2f5598b caif: Bugfix debugfs directory name must be unique.
Race condition caused debugfs_create_dir() to fail due to duplicate
name. Use atomic counter to create unique directory name.

net_ratelimit() is introduced to limit debug printouts.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-15 17:45:56 -04:00
sjur.brandeland@stericsson.com
c85c2951d4 caif: Handle dev_queue_xmit errors.
Do proper handling of dev_queue_xmit errors in order to
avoid double free of skb and leaks in error conditions.
In cfctrl pending requests are removed when CAIF Link layer goes down.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-15 17:45:56 -04:00
sjur.brandeland@stericsson.com
bee925db9a caif: prepare support for namespaces
Use struct net to reference CAIF configuration object instead of static variables.
Refactor functions caif_connect_client, caif_disconnect_client and squach
files cfcnfg.c and caif_config_utils.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-15 17:45:55 -04:00
sjur.brandeland@stericsson.com
b3ccfbe409 caif: Protected in-flight packets using dev or sock refcont.
CAIF Socket Layer and ip-interface registers reference counters
in CAIF service layer. The functions sock_hold, sock_put and
dev_hold, dev_put are used by CAIF Stack to protect from freeing
memory while packets are in-flight.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-15 17:45:55 -04:00
Sjur Brændeland
4dd820c088 caif: Don't resend if dev_queue_xmit fails.
If CAIF Link Layer returns an error, we no longer try to re-build the
CAIF packet and resend it. Instead, we simply return any transmission
errors to the socket client.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-11 15:08:48 -07:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Dan Rosenberg
91b5c98c2e caif: don't set connection request param size before copying data
The size field should not be set until after the data is successfully
copied in.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-10 16:00:54 -08:00
André Carvalho de Matos
f2527ec436 caif: Bugfix for socket priority, bindtodev and dbg channel.
Changes:
o Bugfix: SO_PRIORITY for SOL_SOCKET could not be handled
  in caif's setsockopt,  using the struct sock attribute priority instead.

o Bugfix: SO_BINDTODEVICE for SOL_SOCKET could not be handled
  in caif's setsockopt,  using the struct sock attribute ifindex instead.

o Wrong assert statement for RFM layer segmentation.

o CAIF Debug channels was not working over SPI, caif_payload_info
  containing padding info must be initialized.

o Check on pointer before dereferencing when unregister dev in caif_dev.c

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-03 18:50:03 -07:00
David S. Miller
69259abb64 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/pcmcia/pcnet_cs.c
	net/caif/caif_socket.c
2010-10-06 19:39:31 -07:00
Eric Dumazet
79315068f4 caif: fix two caif_connect() bugs
caif_connect() might dereference a netdevice after dev_put() it.

It also doesnt check dev_get_by_index() return value and could
dereference a NULL pointer.

Fix it, using RCU to avoid taking a reference.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-05 20:35:53 -07:00
Nicolas Kaiser
ee624599d3 caif: remove duplicated include
Remove duplicated include.

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Acked-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-05 00:47:37 -07:00
Sjur Braendeland
9e2e8f14d4 caif: Use default send and receive buffer size in caif_socket.
CAIF sockets should use socket's default send and receive buffers sizes.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-21 18:05:31 -07:00
Sjur Braendeland
b04367df66 caif: Minor fixes in log prints.
Use pr_debug for flow control printouts, and refine an error printout.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-21 18:05:30 -07:00
Joe Perches
b31fa5bad5 net/caif: Use pr_fmt
This patch standardizes caif message logging prefixes.

Add #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
Add missing "\n"s to some logging messages
Convert pr_warning to pr_warn

This changes the logging message prefix from CAIF: to caif:
for all uses but caif_socket.c and chnl_net.c.  Those now use
their filename without extension.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-06 18:48:43 -07:00
Sjur Braendeland
2aa40aef9d caif: Use link layer MTU instead of fixed MTU
Previously CAIF supported maximum transfer size of ~4050.
The transfer size is now calculated dynamically based on the
link layers mtu size.

Signed-off-by: Sjur Braendeland@stericsson.com
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-20 19:46:06 -07:00
Sjur Braendeland
a7da1f55a8 caif: Bugfix - RFM must support segmentation.
CAIF Remote File Manager may send or receive more than 4050 bytes.
Due to this The CAIF RFM service have to support segmentation.

Signed-off-by: Sjur Braendeland@stericsson.com
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-20 19:46:05 -07:00
Dan Carpenter
f5d72af9f3 caif: remove unneeded null check in caif_connect()
We already dereferenced uaddr towards the start of the function when we
checked that "uaddr->sa_family != AF_CAIF".  Both the check here and the
earlier check were added in bece7b2398: "caif: Rewritten socket
implementation".  Before that patch, we assumed that we recieved a valid
pointer for uaddr, and based on that, I have removed this check.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-31 00:24:16 -07:00
Sjur Braendeland
dcda138d2f caif: Bugfix - use MSG_TRUNC in receive
Fixed handling when skb don't fit in user buffer,
instead of returning -EMSGSIZE, the buffer is truncated (just
as unix seqpakcet does).

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-23 23:57:43 -07:00
Sjur Braendeland
a9a8f1070d caif: Bugfix - missing spin_unlock
Splint found missing spin_unlock.
Corrected this an some other trivial split warnings.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-23 23:57:43 -07:00
Sjur Braendeland
ca6a09f25c caif: Bugfix - Poll can't return POLLHUP while connecting.
Discovered bug when testing async connect.
While connecting poll should not return POLLHUP,
but POLLOUT when connected.
Also fixed the sysfs flow-control-counters.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-23 23:57:42 -07:00
Sjur Braendeland
9e4b816bc3 caif: Bugfix - wait_ev*_timeout returns long.
Discovered bug when testing on 64bit architecture.
Fixed by using long to store result from wait_event_interruptible_timeout.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-23 23:57:41 -07:00
Sjur Braendeland
bece7b2398 caif: Rewritten socket implementation
Changes:
 This is a complete re-write of the socket layer. Making the socket
 implementation more aligned with the other socket layers and using more
 of the support functions available in sock.c. Lots of code is copied
 from af_unix (and some from af_irda).
 Non-blocking mode should be working as well.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-28 12:55:14 -07:00
Eric Dumazet
4a4771a58e net: use sk_sleep()
Commit aa395145 (net: sk_sleep() helper) missed three files in the
conversion.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-26 11:18:45 -07:00
Eric Dumazet
aa39514516 net: sk_sleep() helper
Define a new function to return the waitqueue of a "struct sock".

static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
	return sk->sk_sleep;
}

Change all read occurrences of sk_sleep by a call to this function.

Needed for a future RCU conversion. sk_sleep wont be a field directly
available.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-20 16:37:13 -07:00
Sjur Braendeland
e6f95ec8db net-caif: add CAIF socket implementation
Implementation of CAIF sockets for protocol and address family
PF_CAIF and AF_CAIF.
CAIF socket is connection oriented implementing SOCK_SEQPACKET
and SOCK_STREAM interface with supporting blocking and non-blocking mode.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30 19:08:48 -07:00