[IPV6]: MSG_ERRQUEUE messages do not pass to connected raw sockets
From: Dmitry Butskoy <dmitry@butskoy.name>
Taken from http://bugzilla.kernel.org/show_bug.cgi?id=8747
Problem Description:
It is related to the possibility to obtain MSG_ERRQUEUE messages from the udp
and raw sockets, both connected and unconnected.
There is a little typo in net/ipv6/icmp.c code, which prevents such messages
to be delivered to the errqueue of the correspond raw socket, when the socket
is CONNECTED. The typo is due to swap of local/remote addresses.
Consider __raw_v6_lookup() function from net/ipv6/raw.c. When a raw socket is
looked up usual way, it is something like:
sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr, IP6CB(skb)->iif);
where "daddr" is a destination address of the incoming packet (IOW our local
address), "saddr" is a source address of the incoming packet (the remote end).
But when the raw socket is looked up for some icmp error report, in
net/ipv6/icmp.c:icmpv6_notify() , daddr/saddr are obtained from the echoed
fragment of the "bad" packet, i.e. "daddr" is the original destination
address of that packet, "saddr" is our local address. Hence, for
icmpv6_notify() must use "saddr, daddr" in its arguments, not "daddr, saddr"
...
Steps to reproduce:
Create some raw socket, connect it to an address, and cause some error
situation: f.e. set ttl=1 where the remote address is more than 1 hop to reach.
Set IPV6_RECVERR .
Then send something and wait for the error (f.e. poll() with POLLERR|POLLIN).
You should receive "time exceeded" icmp message (because of "ttl=1"), but the
socket do not receive it.
If you do not connect your raw socket, you will receive MSG_ERRQUEUE
successfully. (The reason is that for unconnected socket there are no actual
checks for local/remote addresses).
Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Jean Delvare [Sun, 15 Jul 2007 03:51:44 +0000 (20:51 -0700)]
[IPV4]: Cleanup call to __neigh_lookup()
Back in the times of Linux 2.2, negative values for the creat parameter
of __neigh_lookup() had a particular meaning, but no longer, so we
should pass 1 instead.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Patrick McHardy [Sun, 15 Jul 2007 03:49:26 +0000 (20:49 -0700)]
[NET_SCHED]: Revert "avoid transmit softirq on watchdog wakeup" optimization
As noticed by Ranko Zivojnovic <ranko@spidernet.net>, calling qdisc_run
from the timer handler can result in deadlock:
> CPU#0
>
> qdisc_watchdog() fires and gets dev->queue_lock
> qdisc_run()...qdisc_restart()...
> -> releases dev->queue_lock and enters dev_hard_start_xmit()
>
> CPU#1
>
> tc del qdisc dev ...
> qdisc_graft()...dev_graft_qdisc()...dev_deactivate()...
> -> grabs dev->queue_lock ...
>
> qdisc_reset()...{cbq,hfsc,htb,netem,tbf}_reset()...qdisc_watchdog_cancel()...
> -> hrtimer_cancel() - waiting for the qdisc_watchdog() to exit, while still
> holding dev->queue_lock
>
> CPU#0
>
> dev_hard_start_xmit() returns ...
> -> wants to get dev->queue_lock(!)
>
> DEADLOCK!
The entire optimization is a bit questionable IMO, it moves potentially
large parts of NET_TX_SOFTIRQ work to TIMER_SOFTIRQ/HRTIMER_SOFTIRQ,
which kind of defeats the separation of them.
Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: Ranko Zivojnovic <ranko@spidernet.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Jan Engelhardt [Sun, 15 Jul 2007 03:47:26 +0000 (20:47 -0700)]
[NETFILTER]: x_tables: add connlimit match
ipt_connlimit has been sitting in POM-NG for a long time.
Here is a new shiny xt_connlimit with:
* xtables'ified
* will request the layer3 module
(previously it hotdropped every packet when it was not loaded)
* fixed: there was a deadlock in case of an OOM condition
* support for any layer4 protocol (e.g. UDP/SCTP)
* using jhash, as suggested by Eric Dumazet
* ipv6 support
Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[NETFILTER]: nf_conntrack: Don't track locally generated special ICMP error
The conntrack assigned to locally generated ICMP error is usually the one
assigned to the original packet which has caused the error. But if
the original packet is handled as invalid by nf_conntrack, no conntrack
is assigned to the original packet. Then nf_ct_attach() cannot assign
any conntrack to the ICMP error packet. In that case the current
nf_conntrack_icmp assigns appropriate conntrack to it. But the current
code mistakes the direction of the packet. As a result, NAT code mistakes
the address to be mangled.
To fix the bug, this changes nf_conntrack_icmp not to assign conntrack
to such ICMP error. Actually no address is necessary to be mangled
in this case.
Spotted by Jordan Russell.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[NETFILTER]: nf_conntrack: Introduces nf_ct_get_tuplepr and uses it
nf_ct_get_tuple() requires the offset to transport header and that bothers
callers such as icmp[v6] l4proto modules. This introduces new function
to simplify them.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[NETFILTER]: nf_conntrack: make l3proto->prepare() generic and renames it
The icmp[v6] l4proto modules parse headers in ICMP[v6] error to get tuple.
But they have to find the offset to transport protocol header before that.
Their processings are almost same as prepare() of l3proto modules.
This makes prepare() more generic to simplify icmp[v6] l4proto module
later.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
[NETFILTER]: nf_conntrack: Increment error count on parsing IPv4 header
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Sun, 15 Jul 2007 02:07:52 +0000 (19:07 -0700)]
[NET]: Add ethtool support for NETIF_F_IPV6_CSUM devices.
Add ethtool utility function to set or clear IPV6_CSUM feature flag.
Modify tg3.c and bnx2.c to use this function when doing ethtool -K
to change tx checksum.
Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
The accept_queue of an af_iucv socket will be corrupted, if
adding and deleting of entries in this queue occurs at the
same time (connect request from one client, while accept call
is processed for another client).
Solution: add locking when updating accept_q
Signed-off-by: Ursula Braun <braunu@de.ibm.com> Acked-by: Frank Pavlic <fpavlic@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[AF_IUCV]: Avoid deadlock between iucv_path_connect and tasklet.
An iucv deadlock may occur, where one CPU is spinning on the
iucv_table_lock for iucv_tasklet_fn(), while another CPU is holding
the iucv_table_lock for an iucv_path_connect() and is waiting for
the first CPU in an smp_call_function.
Solution: replace spin_lock in iucv_tasklet_fn by spin_trylock and
reschedule tasklet in case of non-granted lock.
Signed-off-by: Ursula Braun <braunu@de.ibm.com> Acked-by: Frank Pavlic <fpavlic@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Jennifer Hunt [Sun, 15 Jul 2007 02:03:00 +0000 (19:03 -0700)]
[AF_IUCV]: Improve description of IUCV and AFIUCV configuration options.
Signed-off-by: Jennifer Hunt <jenhunt@us.ibm.com> Signed-off-by: Ursula Braun >braunu@de.ibm.com> Acked-by: Frank Pavlic <fpavlic@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
The set_multicast_list function may be called without holding the rtnl
mutex, resulting in races when changing the underlying device's promiscous
and allmulti state. Use the change_rx_mode hook, which is always invoked
under the rtnl.
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Patrick McHardy [Sun, 15 Jul 2007 01:52:02 +0000 (18:52 -0700)]
[NET]: dev_mcast: add multicast list synchronization helpers
The method drivers currently use to synchronize multicast lists is not
very pretty:
- walk the multicast list
- search each entry on a copy of the previous list
- if new add to lower device
- walk the copy of the previous list
- search each entry on the current list
- if removed delete from lower device
- copy entire list
This patch adds a new field to struct dev_addr_list to store the
synchronization state and adds two helper functions for synchronization
and cleanup.
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Patrick McHardy [Sun, 15 Jul 2007 01:51:31 +0000 (18:51 -0700)]
[NET]: Add net_device change_rx_mode callback
Currently the set_multicast_list (and set_rx_mode) callbacks are
responsible for configuring the device according to the IFF_PROMISC,
IFF_MULTICAST and IFF_ALLMULTI flags and the mc_list (and uc_list in
case of set_rx_mode).
These callbacks can be invoked from BH context without the rtnl_mutex
by dev_mc_add/dev_mc_delete, which makes reading the device flags and
promiscous/allmulti count racy. For real hardware drivers that just
commit all changes to the hardware this is not a real problem since
the stack guarantees to call them for every change, so at least the
final call will not race and commit the correct configuration to the
hardware.
For software devices that want to synchronize promiscous and multicast
state to an underlying device however this can cause corruption of the
underlying device's flags or promisc/allmulti counts.
When the software device is concurrently put in promiscous or allmulti
mode while set_multicast_list is invoked from bottem half context, the
device might synchronize the change to the underlying device without
holding the rtnl_mutex, which races with concurrent changes to the
underlying device.
Add a dev->change_rx_flags hook that is invoked when any of the flags
that affect rx filtering change (under the rtnl_mutex), which allows
drivers to perform synchronization immediately and only synchronize
the address lists in set_multicast_list/set_rx_mode.
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
because it changed how CONFIG_NETLABEL worked, and broke older SElinux
policies.
As a result, quoth James Morris:
"Can you please revert this patch?
We thought it only affected people running MLS, but it will affect others.
Sorry for the hassle."
Cc: James Morris <jmorris@namei.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> Cc: Paul Moore <paul.moore@hp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (122 commits)
sunrpc: drop BKL around wrap and unwrap
NFSv4: Make sure unlock is really an unlock when cancelling a lock
NLM: fix source address of callback to client
SUNRPC client: add interface for binding to a local address
SUNRPC server: record the destination address of a request
SUNRPC: cleanup transport creation argument passing
NFSv4: Make the NFS state model work with the nosharedcache mount option
NFS: Error when mounting the same filesystem with different options
NFS: Add the mount option "nosharecache"
NFS: Add support for mounting NFSv4 file systems with string options
NFS: Add final pieces to support in-kernel mount option parsing
NFS: Introduce generic mount client API
NFS: Add enums and match tables for mount option parsing
NFS: Improve debugging output in NFS in-kernel mount client
NFS: Clean up in-kernel NFS mount
NFS: Remake nfsroot_mount as a permanent part of NFS client
SUNRPC: Add a convenient default for the hostname when calling rpc_create()
SUNRPC: Rename rpcb_getport to be consistent with new rpcb_getport_sync name
SUNRPC: Rename rpcb_getport_external routine
SUNRPC: Allow rpcbind requests to be interrupted by a signal.
...
When nfsd was transitioned to use splice instead of sendfile() for data
transfers, a line setting the page index was lost. Restore it, so that
nfsd is functional when that path is used.
* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] Fix typos in powernow-k8 printk's.
[CPUFREQ] Restore previously used governor on a hot-replugged CPU
[CPUFREQ] bugfix cpufreq in combination with performance governor
[CPUFREQ] powernow-k8 compile fix.
[CPUFREQ] the overdue removal of X86_SPEEDSTEP_CENTRINO_ACPI
[CPUFREQ] Longhaul - Option to disable ACPI C3 support
Fixed up arch/i386/kernel/cpu/cpufreq/powernow-k8.c due to revert that
got fixed differently in the cpufreq branch.
Merge branch 'ioat-md-accel-for-linus' of git://lost.foo-projects.org/~dwillia2/git/iop
* 'ioat-md-accel-for-linus' of git://lost.foo-projects.org/~dwillia2/git/iop: (28 commits)
ioatdma: add the unisys "i/oat" pci vendor/device id
ARM: Add drivers/dma to arch/arm/Kconfig
iop3xx: surface the iop3xx DMA and AAU units to the iop-adma driver
iop13xx: surface the iop13xx adma units to the iop-adma driver
dmaengine: driver for the iop32x, iop33x, and iop13xx raid engines
md: remove raid5 compute_block and compute_parity5
md: handle_stripe5 - request io processing in raid5_run_ops
md: handle_stripe5 - add request/completion logic for async expand ops
md: handle_stripe5 - add request/completion logic for async read ops
md: handle_stripe5 - add request/completion logic for async check ops
md: handle_stripe5 - add request/completion logic for async compute ops
md: handle_stripe5 - add request/completion logic for async write ops
md: common infrastructure for running operations with raid5_run_ops
md: raid5_run_ops - run stripe operations outside sh->lock
raid5: replace custom debug PRINTKs with standard pr_debug
raid5: refactor handle_stripe5 and handle_stripe6 (v3)
async_tx: add the async_tx api
xor: make 'xor_blocks' a library routine for use with async_tx
dmaengine: make clients responsible for managing channels
dmaengine: refactor dmaengine around dma_async_tx_descriptor
...
Merge branch 'splice-2.6.23' of git://git.kernel.dk/data/git/linux-2.6-block
* 'splice-2.6.23' of git://git.kernel.dk/data/git/linux-2.6-block:
splice: fix offset mangling with direct splicing (sendfile)
security: revalidate rw permissions for sys_splice and sys_vmsplice
relay: fixup kerneldoc comment
relay: fix bogus cast in subbuf_splice_actor()
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Workaround for a sparse warning in include/asm-mips/mach-tx4927/ioremap.h
[MIPS] Make show_code static and add __user tag
[MIPS] Workaround for a sparse warning in include/asm-mips/compat.h
[MIPS] Add some __user tags
[MIPS] math-emu minor cleanup
[MIPS] Kill CONFIG_TX4927BUG_WORKAROUND
[MIPS] Alchemy: Remove code wrapped by dead symbol CONFIG_FB_XPERT98
[MIPS] Alchemy: Remove code wrapped by dead symbol CONFIG_AU1000_SRC_CLK
[MIPS] Alchemy: Remove code wrapped by dead symbol CONFIG_AU1000_USE32K
[MIPS] Alchemy: Remove code wrapped by dead symbol CONFIG_AU1XXX_PSC_SPI
[CHAR] Delete leftovers of old Alchemy UART driver
- the fields were not aligned properly with the description
- get rid of the lazy-TLB output: it's been quite some time since
we last had a bug there, and when we had a bug it wasnt helped a
bit by this debug output.
Mike Galbraith [Wed, 11 Jul 2007 19:21:47 +0000 (21:21 +0200)]
[PATCH] sched: fix prio_to_wmult[] for nice 1
There's a typo in the values in prio_to_wmult[] for nice level 1. While
it did not cause bad CPU distribution, but caused more rescheduling
between nice-0 and nice-1 tasks than necessary.
Dan Williams [Fri, 13 Jul 2007 15:06:19 +0000 (08:06 -0700)]
ioatdma: add the unisys "i/oat" pci vendor/device id
Cc: John Magolan <john.magolan@unisys.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Tue, 2 Jan 2007 20:52:31 +0000 (13:52 -0700)]
iop3xx: surface the iop3xx DMA and AAU units to the iop-adma driver
Adds the platform device definitions and the architecture specific support
routines (i.e. register initialization and descriptor formats) for the
iop-adma driver.
Changelog:
* add support for > 1k zero sum buffer sizes
* added dma/aau platform devices to iq80321 and iq80332 setup
* fixed the calculation in iop_desc_is_aligned
* support xor buffer sizes larger than 16MB
* fix places where software descriptors are assumed to be contiguous, only
hardware descriptors are contiguous for up to a PAGE_SIZE buffer size
* convert to async_tx
* add interrupt support
* add platform devices for 80219 boards
* do not call platform register macros in driver code
* remove switch() statements for compatible register offsets/layouts
* change over to bitmap based capabilities
* remove unnecessary ARM assembly statement
* checkpatch.pl fixes
* gpl v2 only correction
* phys move to dma_async_tx_descriptor
Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Tue, 2 Jan 2007 20:52:31 +0000 (13:52 -0700)]
iop13xx: surface the iop13xx adma units to the iop-adma driver
Adds the platform device definitions and the architecture specific
support routines (i.e. register initialization and descriptor formats) for the
iop-adma driver.
Changelog:
* added 'descriptor pool size' to the platform data
* add base support for buffer sizes larger than 16MB (hw max)
* build error fix from Kirill A. Shutemov
* rebase for async_tx changes
* add interrupt support
* do not call platform register macros in driver code
* remove unnecessary ARM assembly statement
* checkpatch.pl fixes
* gpl v2 only correction
Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Tue, 2 Jan 2007 20:52:26 +0000 (13:52 -0700)]
dmaengine: driver for the iop32x, iop33x, and iop13xx raid engines
The Intel(R) IOP series of i/o processors integrate an Xscale core with
raid acceleration engines. The capabilities per platform are:
iop219:
(2) copy engines
iop321:
(2) copy engines
(1) xor and block fill engine
iop33x:
(2) copy and crc32c engines
(1) xor, xor zero sum, pq, pq zero sum, and block fill engine
iop34x (iop13xx):
(2) copy, crc32c, xor, xor zero sum, and block fill engines
(1) copy, crc32c, xor, xor zero sum, pq, pq zero sum, and block fill engine
The driver supports the features of the async_tx api:
* asynchronous notification of operation completion
* implicit (interupt triggered) handling of inter-channel transaction
dependencies
The driver adapts to the platform it is running by two methods.
1/ #include <asm/arch/adma.h> which defines the hardware specific
iop_chan_* and iop_desc_* routines as a series of static inline
functions
2/ The private platform data attached to the platform_device defines the
capabilities of the channels
20070626: Callbacks are run in a tasklet. Given the recent discussion on
LKML about killing tasklets in favor of workqueues I did a quick conversion
of the driver. Raid5 resync performance dropped from 50MB/s to 30MB/s, so
the tasklet implementation remains until a generic softirq interface is
available.
Changelog:
* fixed a slot allocation bug in do_iop13xx_adma_xor that caused too few
slots to be requested eventually leading to data corruption
* enabled the slot allocation routine to attempt to free slots before
returning -ENOMEM
* switched the cleanup routine to solely use the software chain and the
status register to determine if a descriptor is complete. This is
necessary to support other IOP engines that do not have status writeback
capability
* make the driver iop generic
* modified the allocation routines to understand allocating a group of
slots for a single operation
* added a null xor initialization operation for the xor only channel on
iop3xx
* support xor operations on buffers larger than the hardware maximum
* split the do_* routines into separate prep, src/dest set, submit stages
* added async_tx support (dependent operations initiation at cleanup time)
* simplified group handling
* added interrupt support (callbacks via tasklets)
* brought the pending depth inline with ioat (i.e. 4 descriptors)
* drop dma mapping methods, suggested by Chris Leech
* don't use inline in C files, Adrian Bunk
* remove static tasklet declarations
* make iop_adma_alloc_slots easier to read and remove chances for a
corrupted descriptor chain
* fix locking bug in iop_adma_alloc_chan_resources, Benjamin Herrenschmidt
* convert capabilities over to dma_cap_mask_t
* fixup sparse warnings
* add descriptor flush before iop_chan_enable
* checkpatch.pl fixes
* gpl v2 only correction
* move set_src, set_dest, submit to async_tx methods
* move group_list and phys to async_tx
Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Tue, 2 Jan 2007 20:52:31 +0000 (13:52 -0700)]
md: handle_stripe5 - request io processing in raid5_run_ops
I/O submission requests were already handled outside of the stripe lock in
handle_stripe. Now that handle_stripe is only tasked with finding work,
this logic belongs in raid5_run_ops.
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:31 +0000 (13:52 -0700)]
md: handle_stripe5 - add request/completion logic for async expand ops
When a stripe is being expanded bulk copying takes place to move the data
from the old stripe to the new. Since raid5_run_ops only operates on one
stripe at a time these bulk copies are handled in-line under the stripe
lock. In the dma offload case we poll for the completion of the operation.
After the data has been copied into the new stripe the parity needs to be
recalculated across the new disks. We reuse the existing postxor
functionality to carry out this calculation. By setting STRIPE_OP_POSTXOR
without setting STRIPE_OP_BIODRAIN the completion path in handle stripe
can differentiate expand operations from normal write operations.
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:31 +0000 (13:52 -0700)]
md: handle_stripe5 - add request/completion logic for async read ops
When a read bio is attached to the stripe and the corresponding block is
marked R5_UPTODATE, then a read (biofill) operation is scheduled to copy
the data from the stripe cache to the bio buffer. handle_stripe flags the
blocks to be operated on with the R5_Wantfill flag. If new read requests
arrive while raid5_run_ops is running they will not be handled until
handle_stripe is scheduled to run again.
Changelog:
* cleanup to_read and to_fill accounting
* do not fail reads that have reached the cache
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:31 +0000 (13:52 -0700)]
md: handle_stripe5 - add request/completion logic for async check ops
Check operations are scheduled when the array is being resynced or an
explicit 'check/repair' command was sent to the array. Previously check
operations would destroy the parity block in the cache such that even if
parity turned out to be correct the parity block would be marked
!R5_UPTODATE at the completion of the check. When the operation can be
carried out by a dma engine the assumption is that it can check parity as a
read-only operation. If raid5_run_ops notices that the check was handled
by hardware it will preserve the R5_UPTODATE status of the parity disk.
When a check operation determines that the parity needs to be repaired we
reuse the existing compute block infrastructure to carry out the operation.
Repair operations imply an immediate write back of the data, so to
differentiate a repair from a normal compute operation the
STRIPE_OP_MOD_REPAIR_PD flag is added.
Changelog:
* remove test_and_set/test_and_clear BUG_ONs, Neil Brown
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:30 +0000 (13:52 -0700)]
md: handle_stripe5 - add request/completion logic for async compute ops
handle_stripe will compute a block when a backing disk has failed, or when
it determines it can save a disk read by computing the block from all the
other up-to-date blocks.
Previously a block would be computed under the lock and subsequent logic in
handle_stripe could use the newly up-to-date block. With the raid5_run_ops
implementation the compute operation is carried out a later time outside
the lock. To preserve the old functionality we take advantage of the
dependency chain feature of async_tx to flag the block as R5_Wantcompute
and then let other parts of handle_stripe operate on the block as if it
were up-to-date. raid5_run_ops guarantees that the block will be ready
before it is used in another operation.
However, this only works in cases where the compute and the dependent
operation are scheduled at the same time. If a previous call to
handle_stripe sets the R5_Wantcompute flag there is no facility to pass the
async_tx dependency chain across successive calls to raid5_run_ops. The
req_compute variable protects against this case.
Changelog:
* remove the req_compute BUG_ON
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:30 +0000 (13:52 -0700)]
md: handle_stripe5 - add request/completion logic for async write ops
After handle_stripe5 decides whether it wants to perform a
read-modify-write, or a reconstruct write it calls
handle_write_operations5. A read-modify-write operation will perform an
xor subtraction of the blocks marked with the R5_Wantprexor flag, copy the
new data into the stripe (biodrain) and perform a postxor operation across
all up-to-date blocks to generate the new parity. A reconstruct write is run
when all blocks are already up-to-date in the cache so all that is needed
is a biodrain and postxor.
On the completion path STRIPE_OP_PREXOR will be set if the operation was a
read-modify-write. The STRIPE_OP_BIODRAIN flag is used in the completion
path to differentiate write-initiated postxor operations versus
expansion-initiated postxor operations. Completion of a write triggers i/o
to the drives.
Changelog:
* make the 'rcw' parameter to handle_write_operations5 a simple flag, Neil Brown
* remove test_and_set/test_and_clear BUG_ONs, Neil Brown
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:30 +0000 (13:52 -0700)]
md: common infrastructure for running operations with raid5_run_ops
All the handle_stripe operations that are to be transitioned to use
raid5_run_ops need a method to coherently gather work under the stripe-lock
and hand that work off to raid5_run_ops. The 'get_stripe_work' routine
runs under the lock to read all the bits in sh->ops.pending that do not
have the corresponding bit set in sh->ops.ack. This modified 'pending'
bitmap is then passed to raid5_run_ops for processing.
The transition from 'ack' to 'completion' does not need similar protection
as the existing release_stripe infrastructure will guarantee that
handle_stripe will run again after a completion bit is set, and
handle_stripe can tolerate a sh->ops.completed bit being set while the lock
is held.
A call to async_tx_issue_pending_all() is added to raid5d to kick the
offload engines once all pending stripe operations work has been submitted.
This enables batching of the submission and completion of operations.
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 20:52:30 +0000 (13:52 -0700)]
md: raid5_run_ops - run stripe operations outside sh->lock
When the raid acceleration work was proposed, Neil laid out the following
attack plan:
1/ move the xor and copy operations outside spin_lock(&sh->lock)
2/ find/implement an asynchronous offload api
The raid5_run_ops routine uses the asynchronous offload api (async_tx) and
the stripe_operations member of a stripe_head to carry out xor+copy
operations asynchronously, outside the lock.
To perform operations outside the lock a new set of state flags is needed
to track new requests, in-flight requests, and completed requests. In this
new model handle_stripe is tasked with scanning the stripe_head for work,
updating the stripe_operations structure, and finally dropping the lock and
calling raid5_run_ops for processing. The following flags outline the
requests that handle_stripe can make of raid5_run_ops:
STRIPE_OP_BIOFILL
- copy data into request buffers to satisfy a read request
STRIPE_OP_COMPUTE_BLK
- generate a missing block in the cache from the other blocks
STRIPE_OP_PREXOR
- subtract existing data as part of the read-modify-write process
STRIPE_OP_BIODRAIN
- copy data out of request buffers to satisfy a write request
STRIPE_OP_POSTXOR
- recalculate parity for new data that has entered the cache
STRIPE_OP_CHECK
- verify that the parity is correct
STRIPE_OP_IO
- submit i/o to the member disks (note this was already performed outside
the stripe lock, but it made sense to add it as an operation type
The flow is:
1/ handle_stripe sets STRIPE_OP_* in sh->ops.pending
2/ raid5_run_ops reads sh->ops.pending, sets sh->ops.ack, and submits the
operation to the async_tx api
3/ async_tx triggers the completion callback routine to set
sh->ops.complete and release the stripe
4/ handle_stripe runs again to finish the operation and optionally submit
new operations that were previously blocked
Note this patch just defines raid5_run_ops, subsequent commits (one per
major operation type) modify handle_stripe to take advantage of this
routine.
Changelog:
* removed ops_complete_biodrain in favor of ops_complete_postxor and
ops_complete_write.
* removed the raid5_run_ops workqueue
* call bi_end_io for reads in ops_complete_biofill, saves a call to
handle_stripe
* explicitly handle the 2-disk raid5 case (xor becomes memcpy), Neil Brown
* fix race between async engines and bi_end_io call for reads, Neil Brown
* remove unnecessary spin_lock from ops_complete_biofill
* remove test_and_set/test_and_clear BUG_ONs, Neil Brown
* remove explicit interrupt handling for channel switching, this feature
was absorbed (i.e. it is now implicit) by the async_tx api
* use return_io in ops_complete_biofill
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Mon, 9 Jul 2007 18:56:43 +0000 (11:56 -0700)]
raid5: replace custom debug PRINTKs with standard pr_debug
Replaces PRINTK with pr_debug, and kills the RAID5_DEBUG definition in
favor of the global DEBUG definition. To get local debug messages just add
'#define DEBUG' to the top of the file.
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Mon, 9 Jul 2007 18:56:43 +0000 (11:56 -0700)]
raid5: refactor handle_stripe5 and handle_stripe6 (v3)
handle_stripe5 and handle_stripe6 have very deep logic paths handling the
various states of a stripe_head. By introducing the 'stripe_head_state'
and 'r6_state' objects, large portions of the logic can be moved to
sub-routines.
'struct stripe_head_state' consumes all of the automatic variables that previously
stood alone in handle_stripe5,6. 'struct r6_state' contains the handle_stripe6
specific variables like p_failed and q_failed.
One of the nice side effects of the 'stripe_head_state' change is that it
allows for further reductions in code duplication between raid5 and raid6.
The following new routines are shared between raid5 and raid6:
Changes:
* v2: fixed 'conf->raid_disk-1' for the raid6 'handle_stripe_expansion' path
* v3: removed the unused 'dirty' field from struct stripe_head_state
* v3: coalesced open coded bi_end_io routines into return_io()
Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Tue, 2 Jan 2007 18:10:44 +0000 (11:10 -0700)]
async_tx: add the async_tx api
The async_tx api provides methods for describing a chain of asynchronous
bulk memory transfers/transforms with support for inter-transactional
dependencies. It is implemented as a dmaengine client that smooths over
the details of different hardware offload engine implementations. Code
that is written to the api can optimize for asynchronous operation and the
api will fit the chain of operations to the available offload resources.
I imagine that any piece of ADMA hardware would register with the
'async_*' subsystem, and a call to async_X would be routed as
appropriate, or be run in-line. - Neil Brown
async_tx exploits the capabilities of struct dma_async_tx_descriptor to
provide an api of the following general format:
async_tx_find_channel() returns a capable channel from its pool. The
channel pool is organized as a per-cpu array of channel pointers. The
async_tx_rebalance() routine is tasked with managing these arrays. In the
uniprocessor case async_tx_rebalance() tries to spread responsibility
evenly over channels of similar capabilities. For example if there are two
copy+xor channels, one will handle copy operations and the other will
handle xor. In the SMP case async_tx_rebalance() attempts to spread the
operations evenly over the cpus, e.g. cpu0 gets copy channel0 and xor
channel0 while cpu1 gets copy channel 1 and xor channel 1. When a
dependency is specified async_tx_find_channel defaults to keeping the
operation on the same channel. A xor->copy->xor chain will stay on one
channel if it supports both operation types, otherwise the transaction will
transition between a copy and a xor resource.
Currently the raid5 implementation in the MD raid456 driver has been
converted to the async_tx api. A driver for the offload engines on the
Intel Xscale series of I/O processors, iop-adma, is provided in a later
commit. With the iop-adma driver and async_tx, raid456 is able to offload
copy, xor, and xor-zero-sum operations to hardware engines.
On iop342 tiobench showed higher throughput for sequential writes (20 - 30%
improvement) and sequential reads to a degraded array (40 - 55%
improvement). For the other cases performance was roughly equal, +/- a few
percentage points. On a x86-smp platform the performance of the async_tx
implementation (in synchronous mode) was also +/- a few percentage points
of the original implementation. According to 'top' on iop342 CPU
utilization drops from ~50% to ~15% during a 'resync' while the speed
according to /proc/mdstat doubles from ~25 MB/s to ~50 MB/s.
The tiobench command line used for testing was: tiobench --size 2048
--block 4096 --block 131072 --dir /mnt/raid --numruns 5
* iop342 had 1GB of memory available
Details:
* if CONFIG_DMA_ENGINE=n the asynchronous path is compiled away by making
async_tx_find_channel a static inline routine that always returns NULL
* when a callback is specified for a given transaction an interrupt will
fire at operation completion time and the callback will occur in a
tasklet. if the the channel does not support interrupts then a live
polling wait will be performed
* the api is written as a dmaengine client that requests all available
channels
* In support of dependencies the api implicitly schedules channel-switch
interrupts. The interrupt triggers the cleanup tasklet which causes
pending operations to be scheduled on the next channel
* Xor engines treat an xor destination address differently than a software
xor routine. To the software routine the destination address is an implied
source, whereas engines treat it as a write-only destination. This patch
modifies the xor_blocks routine to take a an explicit destination address
to mirror the hardware.
Changelog:
* fixed a leftover debug print
* don't allow callbacks in async_interrupt_cond
* fixed xor_block changes
* fixed usage of ASYNC_TX_XOR_DROP_DEST
* drop dma mapping methods, suggested by Chris Leech
* printk warning fixups from Andrew Morton
* don't use inline in C files, Adrian Bunk
* select the API when MD is enabled
* BUG_ON xor source counts <= 1
* implicitly handle hardware concerns like channel switching and
interrupts, Neil Brown
* remove the per operation type list, and distribute operation capabilities
evenly amongst the available channels
* simplify async_tx_find_channel to optimize the fast path
* introduce the channel_table_initialized flag to prevent early calls to
the api
* reorganize the code to mimic crypto
* include mm.h as not all archs include it in dma-mapping.h
* make the Kconfig options non-user visible, Adrian Bunk
* move async_tx under crypto since it is meant as 'core' functionality, and
the two may share algorithms in the future
* move large inline functions into c files
* checkpatch.pl fixes
* gpl v2 only correction
Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-By: NeilBrown <neilb@suse.de>
Dan Williams [Mon, 9 Jul 2007 18:56:42 +0000 (11:56 -0700)]
xor: make 'xor_blocks' a library routine for use with async_tx
The async_tx api tries to use a dma engine for an operation, but will fall
back to an optimized software routine otherwise. Xor support is
implemented using the raid5 xor routines. For organizational purposes this
routine is moved to a common area.
The following fixes are also made:
* rename xor_block => xor_blocks, suggested by Adrian Bunk
* ensure that xor.o initializes before md.o in the built-in case
* checkpatch.pl fixes
* mark calibrate_xor_blocks __init, Adrian Bunk
Cc: Adrian Bunk <bunk@stusta.de> Cc: NeilBrown <neilb@suse.de> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Williams [Mon, 9 Jul 2007 18:56:42 +0000 (11:56 -0700)]
dmaengine: make clients responsible for managing channels
The current implementation assumes that a channel will only be used by one
client at a time. In order to enable channel sharing the dmaengine core is
changed to a model where clients subscribe to channel-available-events.
Instead of tracking how many channels a client wants and how many it has
received the core just broadcasts the available channels and lets the
clients optionally take a reference. The core learns about the clients'
needs at dma_event_callback time.
In support of multiple operation types, clients can specify a capability
mask to only be notified of channels that satisfy a certain set of
capabilities.
Changelog:
* removed DMA_TX_ARRAY_INIT, no longer needed
* dma_client_chan_free -> dma_chan_release: switch to global reference
counting only at device unregistration time, before it was also happening
at client unregistration time
* clients now return dma_state_client to dmaengine (ack, dup, nak)
* checkpatch.pl fixes
* fixup merge with git-ioat
Cc: Chris Leech <christopher.leech@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David S. Miller <davem@davemloft.net>
Dan Williams [Tue, 2 Jan 2007 18:10:43 +0000 (11:10 -0700)]
dmaengine: refactor dmaengine around dma_async_tx_descriptor
The current dmaengine interface defines mutliple routines per operation,
i.e. dma_async_memcpy_buf_to_buf, dma_async_memcpy_buf_to_page etc. Adding
more operation types (xor, crc, etc) to this model would result in an
unmanageable number of method permutations.
Are we really going to add a set of hooks for each DMA engine
whizbang feature?
- Jeff Garzik
The descriptor creation process is refactored using the new common
dma_async_tx_descriptor structure. Instead of per driver
do_<operation>_<dest>_to_<src> methods, drivers integrate
dma_async_tx_descriptor into their private software descriptor and then
define a 'prep' routine per operation. The prep routine allocates a
descriptor and ensures that the tx_set_src, tx_set_dest, tx_submit routines
are valid. Descriptor creation and submission becomes:
tx = dev->device_prep_dma_<operation>(chan, len, int_flag)
tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */)
tx->tx_set_dest(dma_addr_t, tx, index)
tx->tx_submit(tx)
In addition to the refactoring, dma_async_tx_descriptor also lays the
groundwork for definining cross-channel-operation dependencies, and a
callback facility for asynchronous notification of operation completion.
Changelog:
* drop dma mapping methods, suggested by Chris Leech
* fix ioat_dma_dependency_added, also caught by Andrew Morton
* fix dma_sync_wait, change from Andrew Morton
* uninline large functions, change from Andrew Morton
* add tx->callback = NULL to dmaengine calls to interoperate with async_tx
calls
* hookup ioat_tx_submit
* convert channel capabilities to a 'cpumask_t like' bitmap
* removed DMA_TX_ARRAY_INIT, no longer needed
* checkpatch.pl fixes
* make set_src, set_dest, and tx_submit descriptor specific methods
* fixup git-ioat merge
* move group_list and phys to dma_async_tx_descriptor
Cc: Jeff Garzik <jeff@garzik.org> Cc: Chris Leech <christopher.leech@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David S. Miller <davem@davemloft.net>
Tom Zanussi [Thu, 12 Jul 2007 06:12:04 +0000 (08:12 +0200)]
relay: fix bogus cast in subbuf_splice_actor()
The current code that sets the read position in subbuf_splice_actor may
give erroneous results if the buffer size isn't a power of 2. This
patch fixes the problem.
Signed-off-by: Tom Zanussi <zanussi@us.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Dave Jones [Fri, 13 Jul 2007 05:34:10 +0000 (01:34 -0400)]
[CPUFREQ] Fix typos in powernow-k8 printk's.
Based on a patch from Joachim which didn't apply, so I fixed
it up by hand, and also corrected the surrounding indentation
a little.
Signed-off-by: Joachim.Deguara <joachim.deguara@amd.com> Acked-by: Mark Langsdorf <mark.langsdorf@amd.com> Signed-off-by: Dave Jones <davej@redhat.com>
[CPUFREQ] Restore previously used governor on a hot-replugged CPU
Negative side effect: needs NR_CPUs pointer array of memory in
CONFIG_HOTPLUG_CPU case.
Still needs userspace track keeping and rewriting of governors if governors
change while a CPU is not active (always the governor at CPU remove time is
restored).
Move of policy->user_policy.governor assignment is just a minor cleanup.
http://bugzilla.kernel.org/show_bug.cgi?id=8671
Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Mattia Dongili <malattia@linux.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com>
Peter Oruba [Mon, 9 Jul 2007 18:35:27 +0000 (11:35 -0700)]
[CPUFREQ] bugfix cpufreq in combination with performance governor
There is a frequency scaling issue that I encountered with the performance
governor in combination with CPU hotplug.
In cpufreq.c CPU frequency is reduced to its minimum before the CPU gets
unregistered and set offline. Does that have a particular reason?
Since the (k8-)governor does not monitor CPU frequency that setting also
applies then to the remaining CPU as well and lets the system run on the
lowest frequency although performance is chose as the policy.
Signed-off-by: Peter Oruba <peter.oruba@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com>
[CPUFREQ] Longhaul - Option to disable ACPI C3 support
On some motherboards ACPI C3 is available, but it isn't
causing frequency transition on VIA Nehemiah. Longhaul
wasn't working at all earlier, but due to
scaling_cur_speed returning true CPU frequency now, it
looks like CPU is getting stuck at highest frequency
since 2.6.21. I didn't find a reason. Halt is causing
frequency transition.
Signed-off-by: Rafal Bilski <rafalbilski@interia.pl> Signed-off-by: Dave Jones <davej@redhat.com>
It was broken. We most certainly *do* want the default to be the old
behaviour (and the common case!), instead of breaking everybodys
configuration and making 99% of all people have to override the default.
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6: (149 commits)
USB: ohci-pnx4008: Remove unnecessary cast of return value of kzalloc
USB: additions to the quirk list
usb-storage: implement autosuspend
USB: cdc-acm: add new device id to option driver
USB: goku_udc trivial cleanups
USB: usb gadget stack can now -DDEBUG with Kconfig
usb gadget stack: remove usb_ep_*_buffer(), part 2
usb gadget stack: remove usb_ep_*_buffer(), part 1
USB: pxa2xx_udc -- cleanups, mostly removing dma hooks
USB: pxa2xx_udc: use generic gpio layer
USB: quirk for samsung printer
USB: usb/dma doc updates
USB: drivers/usb/storage/unusual_devs.h whitespace cleanup
USB: remove Makefile reference to obsolete OHCI_AT91
USB: io_*: remove bogus termios no change checks
USB: mos7720: remove bogus no termios change check
USB: visor and whiteheat: remove bogus termios change checks
USB: pl2303: remove bogus checks and fix speed support to use tty_get_baud_rate()
USB: mos7840.c: turn this into a serial driver
USB: make the usb_device numa_node get assigned from controller
...
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (76 commits)
IB: Update MAINTAINERS with Hal's new email address
IB/mlx4: Implement query SRQ
IB/mlx4: Implement query QP
IB/cm: Send no match if a SIDR REQ does not match a listen
IB/cm: Fix handling of duplicate SIDR REQs
IB/cm: cm_msgs.h should include ib_cm.h
IB/cm: Include HCA ACK delay in local ACK timeout
IB/cm: Use spin_lock_irq() instead of spin_lock_irqsave() when possible
IB/sa: Make sure SA queries use default P_Key
IPoIB: Recycle loopback skbs instead of freeing and reallocating
IB/mthca: Replace memset(<addr>, 0, PAGE_SIZE) with clear_page(<addr>)
IPoIB/cm: Fix warning if IPV6 is not enabled
IB/core: Take sizeof the correct pointer when calling kmalloc()
IB/ehca: Improve latency by unlocking after triggering the hardware
IB/ehca: Notify consumers of LID/PKEY/SM changes after nondisruptive events
IB/ehca: Return QP pointer in poll_cq()
IB/ehca: Change idr spinlocks into rwlocks
IB/ehca: Refactor sync between completions and destroy_cq using atomic_t
IB/ehca: Lock renaming, static initializers
IB/ehca: Report RDMA atomic attributes in query_qp()
...
CC [M] drivers/net/bnx2.o
drivers/net/bnx2.c: In function 'bnx2_start_xmit':
drivers/net/bnx2.c:5177: warning: implicit declaration of function 'tcp_optlen'
drivers/net/bnx2.c:5181: error: invalid application of 'sizeof' to incomplete type 'struct ipv6hdr'
drivers/net/bnx2.c:5202: error: invalid application of 'sizeof' to incomplete type 'struct tcphdr'
drivers/net/bnx2.c:5207: warning: implicit declaration of function 'tcp_hdr'
drivers/net/bnx2.c:5207: error: invalid type argument of '->'
make[2]: *** [drivers/net/bnx2.o] Error 1
make[1]: *** [drivers/net] Error 2
make: *** [drivers] Error 2
Cc: Ilpo Jävinen <ilpo.jarvinen@helsinki.fi> Cc: David Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Stern [Fri, 6 Jul 2007 18:24:27 +0000 (14:24 -0400)]
usb-storage: implement autosuspend
This patch (as930) implements autosuspend for usb-storage. It is
adapted from a patch by Oliver Neukum. Autosuspend is allowed except
during LUN scanning, resets, and command execution.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David Brownell [Mon, 2 Jul 2007 00:35:28 +0000 (17:35 -0700)]
USB: usb gadget stack can now -DDEBUG with Kconfig
Although the other USB driver directories got taught how use Kconfig
and the Makefile to enable the debugging messages enabled by -DDEBUG,
the gadget stack was overlooked.
This patch remedies that omission, but doesn't update any drivers to
remove previous idiosyncracies in this area ... other than the RNDIS
code, which defined its own DEBUG() macro in a broken way.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David Brownell [Sun, 1 Jul 2007 19:21:00 +0000 (12:21 -0700)]
usb gadget stack: remove usb_ep_*_buffer(), part 2
This patch removes controller driver infrastructure which supported
the now-removed usb_ep_{alloc,free}_buffer() calls.
As can be seen, many of the implementations of this were broken to
various degrees. Many didn't properly return dma-coherent mappings;
those which did so were necessarily ugly because of bogosity in the
underlying dma_free_coherent() calls ... which on many platforms
can't be called from the same contexts (notably in_irq) from which
their dma_alloc_coherent() sibling can be called.
The main potential downside of removing this is that gadget drivers
wouldn't have specific knowledge that the controller drivers have:
endpoints that aren't dma-capable don't need any dma mappings at all.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David Brownell [Sun, 1 Jul 2007 18:04:54 +0000 (11:04 -0700)]
usb gadget stack: remove usb_ep_*_buffer(), part 1
Remove usb_ep_{alloc,free}_buffer() calls, for small dma-coherent buffers.
This patch just removes the interface and its users; later patches will
remove controller driver support.
- This interface is invariably not implemented correctly in the
controller drivers (e.g. using dma pools, a mechanism which
post-dates the interface by several years).
- At this point no gadget driver really *needs* to use it. In
current kernels, any driver that needs such a mechanism could
allocate a dma pool themselves.
Removing this interface is thus a simplification and improvement.
Note that the gmidi.c driver had a bug in this area; fixed.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- Primarily removing unused DMA hooks.
- One "sparse" warning removed
- Remove some Lubbock-only LED hooks (for debugging)
That DMA code was never really completed. It worked, mostly, for IN
transfers (to the host) if they were fortuitously aligned, but that
code was never fully tested. And it was never coded for OUT transfers
(which is where DMA would really help) ... because of chip errata on
essentially every chip other than the pxa255, and because of design
botches (nothing automated data toggle). So it's effectively been
dead code for several years now ... no point in keeping it around.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David Brownell [Mon, 2 Jul 2007 06:33:12 +0000 (23:33 -0700)]
USB: usb/dma doc updates
This patch updates some of the documentation about DMA buffer management
for USB, and ways to avoid extra copying. Our understanding of the issues
has improved over time.
- Most drivers should *avoid* the dma-coherent allocators. There are
a few exceptions (like the HID driver).
- Some methods are currently commented out; it seems folk writing
USB drivers aren't doing performance tuning at that level yet.
- Just avoid highmem; there's no good way to pass an "I can do highmem
DMA" capability through a driver stack. This is easy, everything
already avoids highmem. But it'd be nice if x86_32 systems with much
physical memory could use it directly with network adapters and mass
storage devices. (Patch, anyone?)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
projects / linux-2.6 / log