Validation of skb can be pretty expensive :
GSO segmentation and/or checksum computations.
We can do this without holding qdisc lock, so that other cpus
can queue additional packets.
Trick is that requeued packets were already validated, so we carry
a boolean so that sch_direct_xmit() can validate a fresh skb list,
or directly use an old one.
Tested on 40Gb NIC (8 TX queues) and 200 concurrent flows, 48 threads
host.
Turning TSO on or off had no effect on throughput, only few more cpu
cycles. Lock contention on qdisc lock disappeared.
Same if disabling TX checksum offload.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The return value is not used by callers of these functions
so change the functions to return void.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Users of bio_clone_fast() do not want bios with their own bvecs.
Allocating a bvec mempool as part of the bioset intended for such users
is a waste of memory.
bioset_create_nobvec() creates a bioset that doesn't have the bvec
mempool.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Based on DaveM's recent API work on dev_hard_start_xmit(), that allows
sending/processing an entire skb list.
This patch implements qdisc bulk dequeue, by allowing multiple packets
to be dequeued in dequeue_skb().
The optimization principle for this is two fold, (1) to amortize
locking cost and (2) avoid expensive tailptr update for notifying HW.
(1) Several packets are dequeued while holding the qdisc root_lock,
amortizing locking cost over several packet. The dequeued SKB list is
processed under the TXQ lock in dev_hard_start_xmit(), thus also
amortizing the cost of the TXQ lock.
(2) Further more, dev_hard_start_xmit() will utilize the skb->xmit_more
API to delay HW tailptr update, which also reduces the cost per
packet.
One restriction of the new API is that every SKB must belong to the
same TXQ. This patch takes the easy way out, by restricting bulk
dequeue to qdisc's with the TCQ_F_ONETXQUEUE flag, that specifies the
qdisc only have attached a single TXQ.
Some detail about the flow; dev_hard_start_xmit() will process the skb
list, and transmit packets individually towards the driver (see
xmit_one()). In case the driver stops midway in the list, the
remaining skb list is returned by dev_hard_start_xmit(). In
sch_direct_xmit() this returned list is requeued by dev_requeue_skb().
To avoid overshooting the HW limits, which results in requeuing, the
patch limits the amount of bytes dequeued, based on the drivers BQL
limits. In-effect bulking will only happen for BQL enabled drivers.
Small amounts for extra HoL blocking (2x MTU/0.24ms) were
measured at 100Mbit/s, with bulking 8 packets, but the
oscillating nature of the measurement indicate something, like
sched latency might be causing this effect. More comparisons
show, that this oscillation goes away occationally. Thus, we
disregard this artifact completely and remove any "magic" bulking
limit.
For now, as a conservative approach, stop bulking when seeing TSO and
segmented GSO packets. They already benefit from bulking on their own.
A followup patch add this, to allow easier bisect-ability for finding
regressions.
Jointed work with Hannes, Daniel and Florian.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a LIO storage engine that presents commands to userspace for execution.
This would allow more complex backstores to be implemented out-of-kernel,
and also make experimentation a-la FUSE (but at the SCSI level -- "SUSE"?)
possible.
It uses a mmap()able UIO device per LUN to share a command ring and data
area. The commands are raw SCSI CDBs and iovs for in/out data. The command
ring is also reused for returning scsi command status and optional sense
data.
This implementation is based on Shaohua Li's earlier version but heavily
modified. Differences include:
* Shared memory allocated by kernel, not locked-down user pages
* Single ring for command request and response
* Offsets instead of embedded pointers
* Generic SCSI CDB passthrough instead of per-cmd specialization in ring
format.
* Uses UIO device instead of anon_file passed in mailbox.
* Optional in-kernel handling of some commands.
The main reason for these differences is to permit greater resiliency
if the user process dies or hangs.
Things not yet implemented (on purpose):
* Zero copy. The data area is flexible enough to allow page flipping or
backend-allocated pages to be used by fabrics, but it's not clear these
are performance wins. Can come later.
* Out-of-order command completion by userspace. Possible to add by just
allowing userspace to change cmd_id in rsp cmd entries, but currently
not supported.
* No locks between kernel cmd submission and completion routines. Sounds
like it's possible, but this can come later.
* Sparse allocation of mmaped area. Current code vmallocs the whole thing.
If the mapped area was larger and not fully mapped then the driver would
have more freedom to change cmd and data area sizes based on demand.
Current code open issues:
* The use of idrs may be overkill -- we maybe can replace them with a
simple counter to generate cmd_ids, and a hash table to get a cmd_id's
associated pointer.
* Use of a free-running counter for cmd ring instead of explicit modulo
math. This would require power-of-2 cmd ring size.
(Add kconfig depends NET - Randy)
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
There are some circumstances that call for trying to write an EFI
variable in a non-blocking way. One such scenario is when writing pstore
data in efi_pstore_write() via the pstore_dump() kdump callback.
Now that we have an EFI runtime spinlock we need a way of aborting if
there is contention instead of spinning, since when writing pstore data
from the kdump callback, the runtime lock may already be held by the CPU
that's running the callback if we crashed in the middle of an EFI
variable operation.
The situation is sufficiently special that a new EFI variable operation
is warranted.
Introduce ->set_variable_nonblocking() for this use case. It is an
optional EFI backend operation, and need only be implemented by those
backends that usually acquire locks to serialize access to EFI
variables, as is the case for virt_efi_set_variable() where we now grab
the EFI runtime spinlock.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
At the moment, there are three architectures debug-printing the EFI memory
map at initialization: x86, ia64, and arm64. They all use different format
strings, plus the EFI memory type and the EFI memory attributes are
similarly hard to decode for a human reader.
Introduce a helper __init function that formats the memory type and the
memory attributes in a unified way, to a user-provided character buffer.
The array "memory_type_name" is copied from the arm64 code, temporarily
duplicating it. The (otherwise optional) braces around each string literal
in the initializer list are dropped in order to match the kernel coding
style more closely. The element size is tightened from 32 to 20 bytes
(maximum actual string length + 1) so that we can derive the field width
from the element size.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[ Dropped useless 'register' keyword, which compiler will ignore ]
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Add the following macro from the UEFI spec, for completeness:
EFI_MEMORY_UCE Memory cacheability attribute: The memory region
supports being configured as not cacheable, exported,
and supports the "fetch and add" semaphore mechanism.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
There should be a generic function to parse params like a=b,c
Adding parse_option_str in lib/cmdline.c which will return true
if there's specified option set in the params.
Also updated efi=old_map parsing code to use the new function
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
noefi param can be used for arches other than X86 later, thus move it
out of x86 platform code.
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
We need a way to customize the behaviour of the EFI boot stub, in
particular, we need a way to disable the "chunking" workaround, used
when reading files from the EFI System Partition.
One of my machines doesn't cope well when reading files in 1MB chunks to
a buffer above the 4GB mark - it appears that the "chunking" bug
workaround triggers another firmware bug. This was only discovered with
commit 4bf7111f50 ("x86/efi: Support initrd loaded above 4G"), and
that commit is perfectly valid. The symptom I observed was a corrupt
initrd rather than any kind of crash.
efi= is now used to specify EFI parameters in two very different
execution environments, the EFI boot stub and during kernel boot.
There is also a slight performance optimization by enabling efi=nochunk,
but that's offset by the fact that you're more likely to run into
firmware issues, at least on x86. This is the rationale behind leaving
the workaround enabled by default.
Also provide some documentation for EFI_READ_CHUNK_SIZE and why we're
using the current value of 1MB.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Roy Franz <roy.franz@linaro.org>
Cc: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
The "cpu_data" are defined for some archs and thus conflicting with the
"cpu_data" member in the struct gpd_cpu_data. This causes a compiler
error for those archs.
Let's fix it by rename the member to cpuidle_data. In this context it
also seems appropriate to rename the struct to gpd_cpuidle_data to
better reflect its use.
Fixes: f48c767ce8 (PM / Domains: Move dev_pm_domain_attach|detach() to pm_domain.h)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a quirk for a host controller that always sets
a Transfer Complete interrupt status for the stop
command even when a busy response is not indicated.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
To be able to use an initially unmapped initrd with xen the following
header files must be synced to a newer version from the xen tree:
include/xen/interface/elfnote.h
include/xen/interface/xen.h
As the KEXEC and DUMPCORE related ELFNOTES are not relevant for the
kernel they are omitted from elfnote.h.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
In order to prevent a O(n) search of the filesystem to link up its uio
node with its target configuration, TCMU needs to know the minor number
that UIO assigned. Expose the definition of this struct so TCMU can
access this field.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Commit f0bab73cb5 ("locking/lockdep: Restrict the use of recursive
read_lock() with qrwlock") changed lockdep to try and conform to the
qrwlock semantics which differ from the traditional rwlock semantics.
In particular qrwlock is fair outside of interrupt context, but in
interrupt context readers will ignore all fairness.
The problem modeling this is that read and write side have different
lock state (interrupts) semantics but we only have a single
representation of these. Therefore lockdep will get confused, thinking
the lock can cause interrupt lock inversions.
So revert it for now; the old rwlock semantics were already imperfectly
modeled and the qrwlock extra won't fit either.
If we want to properly fix this, I think we need to resurrect the work
by Gautham did a few years ago that split the read and write state of
locks:
http://lwn.net/Articles/332801/
FWIW the locking selftest that would've failed (and was reported by
Borislav earlier) is something like:
RL(X1); /* IRQ-ON */
LOCK(A);
UNLOCK(A);
RU(X1);
IRQ_ENTER();
RL(X1); /* IN-IRQ */
RU(X1);
IRQ_EXIT();
At which point it would report that because A is an IRQ-unsafe lock we
can suffer the following inversion:
CPU0 CPU1
lock(A)
lock(X1)
lock(A)
<IRQ>
lock(X1)
And this is 'wrong' because X1 can recurse (assuming the above lock are
in fact read-lock) but lockdep doesn't know about this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Waiman Long <Waiman.Long@hp.com>
Cc: ego@linux.vnet.ibm.com
Cc: bp@alien8.de
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20140930132600.GA7444@worktop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch changes the __init_end address to a
page align address, so that free_initmem() can
free the whole .init section, because if the end
address is not page aligned, it will round down to
a page align address, then the tail unligned page
will not be freed.
Signed-off-by: wang <yalin.wang2010@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Conflicts:
drivers/net/usb/r8152.c
net/netfilter/nfnetlink.c
Both r8152 and nfnetlink conflicts were simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce netdev IOCTLs, to be used by the debug tools.
Allows to read/write single dword value or
memory block, aligned to dword
Different address modes supported:
- BAR offset
- Firmware "linker" address
- target's AHB bus
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The DSP driver needs to know widget control value in its event handler for
widgets like mixers. This is required in the subsequent patches
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
* Consistently use the multi-line comment style for networking code:
/* This
* That
* The other thing
*/
* Use single-line comment style for comments with only one line of text.
* In general follow the leading '*' of each line of a comment with a
single space and then text.
* Add missing line break between functions, remove double line break,
align comments to previous lines whenever possible.
Reported-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
You can use physdev to match the physical interface enslaved to the
bridge device. This information is stored in skb->nf_bridge and it is
set up by br_netfilter. So, this is only available when iptables is
used from the bridge netfilter path.
Since 34666d4 ("netfilter: bridge: move br_netfilter out of the core"),
the br_netfilter code is modular. To reduce the impact of this change,
we can autoload the br_netfilter if the physdev match is used since
we assume that the users need br_netfilter in place.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move nf_send_reset() and nf_send_reset6() to nf_reject_ipv4 and
nf_reject_ipv6 respectively. This code is shared by x_tables and
nf_tables.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch introduces the NFT_REJECT_ICMPX_UNREACH type which provides
an abstraction to the ICMP and ICMPv6 codes that you can use from the
inet and bridge tables, they are:
* NFT_REJECT_ICMPX_NO_ROUTE: no route to host - network unreachable
* NFT_REJECT_ICMPX_PORT_UNREACH: port unreachable
* NFT_REJECT_ICMPX_HOST_UNREACH: host unreachable
* NFT_REJECT_ICMPX_ADMIN_PROHIBITED: administratevely prohibited
You can still use the specific codes when restricting the rule to match
the corresponding layer 3 protocol.
I decided to not overload the existing NFT_REJECT_ICMP_UNREACH to have
different semantics depending on the table family and to allow the user
to specify ICMP family specific codes if they restrict it to the
corresponding family.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
commit 98e90de99a
"mmc: host: switch OF parser to use gpio descriptors"
switched the semantic behaviour of card detect and read
only flags such that the inversion capability flag would
only be set if inversion was explicitly specified in the
device tree, in the hopes that no-one was using double
inversion.
It turns out that the XOR:ing between the explicit
inversion was indeed in use, so we need to restore the
old semantics where both ways of inversion are checked
and the end result XOR:ed.
Reported-by: Javier Martinez Canillas <javier@dowhile0.org>
Tested-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This event closes an important gap in the bus notifiers.
There is already the BUS_NOTIFY_DEL_DEVICE event, but that
is sent when the device is still bound to its device driver.
This is too early for the IOMMU code to destroy any mappings
for the device, as they might still be in use by the driver.
The new BUS_NOTIFY_REMOVED_DEVICE event introduced with this
patch closes this gap as it is sent when the device is
already unbound from its device driver and almost completly
removed from the driver core.
With this event the IOMMU code can safely destroy any
mappings and other data structures when a device is removed.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Jerry Hoemann <jerry.hoemann@hp.com>
Pull networking fixes from David Miller:
1) Don't halt the firmware in r8152 driver, from Hayes Wang.
2) Handle full sized 802.1ad frames in bnx2 and tg3 drivers properly,
from Vlad Yasevich.
3) Don't sleep while holding tx_clean_lock in netxen driver, fix from
Manish Chopra.
4) Certain kinds of ipv6 routes can end up endlessly failing the route
validation test, causing it to be re-looked up over and over again.
This particularly kills input route caching in TCP sockets. Fix
from Hannes Frederic Sowa.
5) netvsc_start_xmit() has a use-after-free access to skb->len, fix
from K Y Srinivasan.
6) Fix matching of inverted containers in ematch module, from Ignacy
Gawędzki.
7) Aggregation of GRO frames via SKB ->frag_list for linear skbs isn't
handled properly, regression fix from Eric Dumazet.
8) Don't test return value of ipv4_neigh_lookup(), which returns an
error pointer, against NULL. From WANG Cong.
9) Fix an old regression where we mistakenly allow a double add of the
same tunnel. Fixes from Steffen Klassert.
10) macvtap device delete and open can run in parallel and corrupt lists
etc., fix from Vlad Yasevich.
11) Fix build error with IPV6=m NETFILTER_XT_TARGET_TPROXY=y, from Pablo
Neira Ayuso.
12) rhashtable_destroy() triggers lockdep splats, fix also from Pablo.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (32 commits)
bna: Update Maintainer Email
r8152: disable power cut for RTL8153
r8152: remove clearing bp
bnx2: Correctly receive full sized 802.1ad fragmes
tg3: Allow for recieve of full-size 8021AD frames
r8152: fix setting RTL8152_UNPLUG
netxen: Fix bug in Tx completion path.
netxen: Fix BUG "sleeping function called from invalid context"
ipv6: remove rt6i_genid
hyperv: Fix a bug in netvsc_start_xmit()
net: stmmac: fix stmmac_pci_probe failed when CONFIG_HAVE_CLK is selected
ematch: Fix matching of inverted containers.
gro: fix aggregation for skb using frag_list
neigh: check error pointer instead of NULL for ipv4_neigh_lookup()
ip6_gre: Return an error when adding an existing tunnel.
ip6_vti: Return an error when adding an existing tunnel.
ip6_tunnel: Return an error when adding an existing tunnel.
ip6gre: add a rtnl link alias for ip6gretap
net/mlx4_core: Allow not to specify probe_vf in SRIOV IB mode
r8152: fix the carrier off when autoresuming
...
This fixes the following crash:
[ 63.976822] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 63.980094] CPU: 1 PID: 15 Comm: ksoftirqd/1 Not tainted 3.17.0-rc6+ #648
[ 63.980094] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 63.980094] task: ffff880117dea690 ti: ffff880117dfc000 task.ti: ffff880117dfc000
[ 63.980094] RIP: 0010:[<ffffffff817e6d07>] [<ffffffff817e6d07>] u32_destroy_key+0x27/0x6d
[ 63.980094] RSP: 0018:ffff880117dffcc0 EFLAGS: 00010202
[ 63.980094] RAX: ffff880117dea690 RBX: ffff8800d02e0820 RCX: 0000000000000000
[ 63.980094] RDX: 0000000000000001 RSI: 0000000000000002 RDI: 6b6b6b6b6b6b6b6b
[ 63.980094] RBP: ffff880117dffcd0 R08: 0000000000000000 R09: 0000000000000000
[ 63.980094] R10: 00006c0900006ba8 R11: 00006ba100006b9d R12: 0000000000000001
[ 63.980094] R13: ffff8800d02e0898 R14: ffffffff817e6d4d R15: ffff880117387a30
[ 63.980094] FS: 0000000000000000(0000) GS:ffff88011a800000(0000) knlGS:0000000000000000
[ 63.980094] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 63.980094] CR2: 00007f07e6732fed CR3: 000000011665b000 CR4: 00000000000006e0
[ 63.980094] Stack:
[ 63.980094] ffff88011a9cd300 ffffffff82051ac0 ffff880117dffce0 ffffffff817e6d68
[ 63.980094] ffff880117dffd70 ffffffff810cb4c7 ffffffff810cb3cd ffff880117dfffd8
[ 63.980094] ffff880117dea690 ffff880117dea690 ffff880117dfffd8 000000000000000a
[ 63.980094] Call Trace:
[ 63.980094] [<ffffffff817e6d68>] u32_delete_key_freepf_rcu+0x1b/0x1d
[ 63.980094] [<ffffffff810cb4c7>] rcu_process_callbacks+0x3bb/0x691
[ 63.980094] [<ffffffff810cb3cd>] ? rcu_process_callbacks+0x2c1/0x691
[ 63.980094] [<ffffffff817e6d4d>] ? u32_destroy_key+0x6d/0x6d
[ 63.980094] [<ffffffff810780a4>] __do_softirq+0x142/0x323
[ 63.980094] [<ffffffff810782a8>] run_ksoftirqd+0x23/0x53
[ 63.980094] [<ffffffff81092126>] smpboot_thread_fn+0x203/0x221
[ 63.980094] [<ffffffff81091f23>] ? smpboot_unpark_thread+0x33/0x33
[ 63.980094] [<ffffffff8108e44d>] kthread+0xc9/0xd1
[ 63.980094] [<ffffffff819e00ea>] ? do_wait_for_common+0xf8/0x125
[ 63.980094] [<ffffffff8108e384>] ? __kthread_parkme+0x61/0x61
[ 63.980094] [<ffffffff819e43ec>] ret_from_fork+0x7c/0xb0
[ 63.980094] [<ffffffff8108e384>] ? __kthread_parkme+0x61/0x61
tp could be freed in call_rcu callback too, the order is not guaranteed.
John Fastabend says:
====================
Its worth noting why this is safe. Any running schedulers will either
read the valid class field or it will be zeroed.
All schedulers today when the class is 0 do a lookup using the
same call used by the tcf_exts_bind(). So even if we have a running
classifier hit the null class pointer it will do a lookup and get
to the same result. This is particularly fragile at the moment because
the only way to verify this is to audit the schedulers call sites.
====================
Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
->page_mkwrite() is used by filesystems to allocate blocks under a page
which is becoming writeably mmapped in some process' address space. This
allows a filesystem to return a page fault if there is not enough space
available, user exceeds quota or similar problem happens, rather than
silently discarding data later when writepage is called.
However VFS fails to call ->page_mkwrite() in all the cases where
filesystems need it when blocksize < pagesize. For example when
blocksize = 1024, pagesize = 4096 the following is problematic:
ftruncate(fd, 0);
pwrite(fd, buf, 1024, 0);
map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0);
map[0] = 'a'; ----> page_mkwrite() for index 0 is called
ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */
mremap(map, 1024, 10000, 0);
map[4095] = 'a'; ----> no page_mkwrite() called
At the moment ->page_mkwrite() is called, filesystem can allocate only
one block for the page because i_size == 1024. Otherwise it would create
blocks beyond i_size which is generally undesirable. But later at
->writepage() time, we also need to store data at offset 4095 but we
don't have block allocated for it.
This patch introduces a helper function filesystems can use to have
->page_mkwrite() called at all the necessary moments.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
skb_udp_segment is the function called from udp4_ufo_fragment to
segment a UDP tunnel packet. This function currently assumes
segmentation is transparent Ethernet bridging (i.e. VXLAN
encapsulation). This patch generalizes the function to
operate on either Ethertype or IP protocol.
The inner_protocol field must be set to the protocol of the inner
header. This can now be either an Ethertype or an IP protocol
(in a union). A new flag in the skbuff indicates which type is
effective. skb_set_inner_protocol and skb_set_inner_ipproto
helper functions were added to set the inner_protocol. These
functions are called from the point where the tunnel encapsulation
is occuring.
When skb_udp_tunnel_segment is called, the function to segment the
inner packet is selected based on the inner IP or Ethertype. In the
case of an IP protocol encapsulation, the function is derived from
inet[6]_offloads. In the case of Ethertype, skb->protocol is
set to the inner_protocol and skb_mac_gso_segment is called. (GRE
currently does this, but it might be possible to lookup the protocol
in offload_base and call the appropriate segmenation function
directly).
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The target code has a rather generous helping of smp_mb__after_atomic()
throughout the code base. Most atomic operations were followed by one
and none were preceded by smp_mb__before_atomic(), nor accompanied by a
comment explaining the need for a barrier.
Instead of trying to prove for every case whether or not it is needed,
this patch introduces atomic_inc_mb() and atomic_dec_mb(), which
explicitly include the memory barriers before and after the atomic
operation. For now they are defined in a target header, although they
could be of general use.
Most of the existing atomic/mb combinations were replaced by the new
helpers. In a few cases the atomic was sandwiched in
spin_lock/spin_unlock and I simply removed the barrier.
I suspect that in most cases the correct conversion would have been to
drop the barrier. I also suspect that a few cases exist where a) the
barrier was necessary and b) a second barrier before the atomic would
have been necessary and got added by this patch.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Lets use a proper structure to clearly document and implement
skb fast clones.
Then, we might experiment more easily alternative layouts.
This patch adds a new skb_fclone_busy() helper, used by tcp and xfrm,
to stop leaking of implementation details.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* pci/host-generic:
arm64: Add architectural support for PCI
PCI: Add pci_remap_iospace() to map bus I/O resources
of/pci: Add support for parsing PCI host bridge resources from DT
of/pci: Add pci_get_new_domain_nr() and of_get_pci_domain_nr()
PCI: Add generic domain handling
of/pci: Fix the conversion of IO ranges into IO resources
of/pci: Move of_pci_range_to_resource() to of/address.c
ARM: Define PCI_IOBASE as the base of virtual PCI IO space
of/pci: Add pci_register_io_range() and pci_pio_to_address()
asm-generic/io.h: Fix ioport_map() for !CONFIG_GENERIC_IOMAP
Conflicts:
drivers/pci/host/pci-tegra.c
"msi_attrib.pos" is only used for MSI (not MSI-X), and we already cache the
MSI capability offset in "dev->msi_cap".
Remove "pos" from the struct msi_attrib and use "dev->msi_cap" directly.
[bhelgaas: changelog, fix whitespace]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
After commit 1c51b50c29 ("PCI/MSI: Export MSI mode using attributes, not
kobjects"), the kobject in struct msi_desc is unused.
Remove the unused struct kobject from struct msi_desc.
[bhelgaas: changelog]
Fixes: 1c51b50c29 ("PCI/MSI: Export MSI mode using attributes, not kobjects")
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No architectures implement arch_msi_check_device() or the struct msi_chip
.check_device() method, so remove them.
Remove the "type" parameter to pci_msi_check_device() because it was only
used to call arch_msi_check_device() and is no longer needed.
[bhelgaas: changelog, split to separate patch]
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
