Install the callbacks via the state machine. The notifier in struct
ring_buffer is replaced by the multi instance interface. Upon
__ring_buffer_alloc() invocation, cpuhp_state_add_instance() will invoke
the trace_rb_cpu_prepare() on each CPU.
This callback may now fail. This means __ring_buffer_alloc() will fail and
cleanup (like previously) and during a CPU up event this failure will not
allow the CPU to come up.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161126231350.10321-7-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
It now has only one field and is only used in one structure.
So replaced it in that structure by the field it contains.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
An open file description (struct file) in a given process can be
associated with two different lock owners.
It can have a Posix lock owner which will be different in each process
that has a fd on the file.
It can have a Flock owner which will be the same in all processes.
When searching for a lock stateid to use, we need to consider both of these
owners
So add a new "flock_owner" to the "nfs_open_context" (of which there
is one for each open file description).
This flock_owner does not need to be reference-counted as there is a
1-1 relation between 'struct file' and nfs open contexts,
and it will never be part of a list of contexts. So there is no need
for a 'flock_context' - just the owner is enough.
The io_count included in the (Posix) lock_context provides no
guarantee that all read-aheads that could use the state have
completed, so not supporting it for flock locks in not a serious
problem. Synchronization between flock and read-ahead can be added
later if needed.
When creating an open_context for a non-openning create call, we don't have
a 'struct file' to pass in, so the lock context gets initialized with
a NULL owner, but this will never be used.
The flock_owner is not used at all in this patch, that will come later.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
this field is not used in any important way and probably should
have been removed by
Commit: 8003d3c4aa ("nfs4: treat lock owners as opaque values")
which removed the pid argument from nfs4_get_lock_state.
Except in unusual and uninteresting cases, two threads with the same
->tgid will have the same ->files pointer, so keeping them both
for comparison brings no benefit.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add XDR encoding for the layoutreturn op, and storage for the layoutreturn
arguments to the DELEGRETURN compound.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add XDR encoding for the layoutreturn op, and storage for the layoutreturn
arguments to the CLOSE compound.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add acpi_resource_consumer(). This takes a struct resource and searches
the ACPI namespace for a device whose current resource settings (_CRS)
includes the resource. It returns the device if it exists, or NULL if no
device uses the resource.
If more than one device uses the resource (this may happen in the case of
bridges), acpi_resource_consumer() returns the first one found by
acpi_get_devices() in its modified depth-first walk of the namespace.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Beyond vfio_iommu events, users might also be interested in
vfio_group events. For example, if a vfio_group is used along
with Qemu/KVM, whenever kvm pointer is set to/cleared from the
vfio_group, users could be notified.
Currently only VFIO_GROUP_NOTIFY_SET_KVM supported.
Cc: Kirti Wankhede <kwankhede@nvidia.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
[aw: remove use of new typedef]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently vfio_register_notifier assumes that there is only one
notifier chain, which is in vfio_iommu. However, the user might
also be interested in events other than vfio_iommu, for example,
vfio_group. Refactor vfio_{un}register_notifier implementation
to make it feasible.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Jike Song <jike.song@intel.com>
[aw: merge with commit 816ca69ea9c7 ("vfio: Fix handling of error returned by 'vfio_group_get_from_dev()'"), remove typedef]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add new parameter mdix_ctrl to hold the user configuration.
Existing mdix maintain the current status of MDI(X) crossover performed or
not.
mdix_ctrl can configure either ETH_TP_MDI or ETH_TP_MDI_X orETH_TP_MDI_AUTO.
Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the command structure, optional command set support (ONCS) bit and
a new error code for the Write Zeroes command.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This adds a new block layer operation to zero out a range of
LBAs. This allows to implement zeroing for devices that don't use
either discard with a predictable zero pattern or WRITE SAME of zeroes.
The prominent example of that is NVMe with the Write Zeroes command,
but in the future, this should also help with improving the way
zeroing discards work. For this operation, suitable entry is exported in
sysfs which indicate the number of maximum bytes allowed in one
write zeroes operation by the device.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Similar to __blkdev_issue_discard this variant allows submitting
the final bio asynchronously and chaining multiple ranges
into a single completion.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Alarm timers are one of the mechanisms to wake up a system from suspend,
but there exist no tracepoints to analyse which process/thread armed an
alarmtimer.
Add tracepoints for start/cancel/expire of individual alarm timers and one
for tracing the suspend time decision when to resume the system.
The following trace excerpt illustrates the new mechanism:
Binder:3292_2-3304 [000] d..2 149.981123: alarmtimer_cancel:
alarmtimer:ffffffc1319a7800 type:REALTIME
expires:1325463120000000000 now:1325376810370370245
Binder:3292_2-3304 [000] d..2 149.981136: alarmtimer_start:
alarmtimer:ffffffc1319a7800 type:REALTIME
expires:1325376840000000000 now:1325376810370384591
Binder:3292_9-3953 [000] d..2 150.212991: alarmtimer_cancel:
alarmtimer:ffffffc1319a5a00 type:BOOTTIME
expires:179552000000 now:150154008122
Binder:3292_9-3953 [000] d..2 150.213006: alarmtimer_start:
alarmtimer:ffffffc1319a5a00 type:BOOTTIME
expires:179551000000 now:150154025622
system_server-3000 [002] ...1 162.701940: alarmtimer_suspend:
alarmtimer type:REALTIME expires:1325376840000000000
The wakeup time which is selected at suspend time allows to map it back to
the task arming the timer: Binder:3292_2.
[ tglx: Store alarm timer expiry time instead of some useless RTC relative
information, add proper type information for wakeups which are
handled via the clock_nanosleep/freezer and massage the changelog. ]
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Link: http://lkml.kernel.org/r/1480372524-15181-5-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Documentation/filesystems/configfs/configfs.txt says:
"When unlink(2) is called on the symbolic link, the source item is
notified via the ->drop_link() method. Like the ->drop_item() method,
this is a void function and cannot return failure."
The ->drop_item() is indeed a void function, the ->drop_link() is
actually not. This, together with the fact that the value of ->drop_link()
is silently ignored suggests, that it is the ->drop_link() return
type that should be corrected and changed to void.
This patch changes drop_link() signature and all its users.
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
[hch: reverted reformatting of some code]
Signed-off-by: Christoph Hellwig <hch@lst.de>
If struct rmi_device_platform_data contains pointers to other struct,
it gets difficult to allocate a fixed size struct and copy it over between
drivers.
Change the pointers into a struct and change the code in rmi4 accordingly.
Reviewed-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Clean up: Completion status is already reported in the individual
completion handlers. Save a few bytes in struct svc_rdma_op_ctxt.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: sc_dma_used is not required for correct operation. It is
simply a debugging tool to report when svcrdma has leaked DMA maps.
However, manipulating an atomic has a measurable CPU cost, and DMA
map accounting specific to svcrdma will be meaningless once svcrdma
is converted to use the new generic r/w API.
A similar kind of debug accounting can be done simply by enabling
the IOMMU or by using CONFIG_DMA_API_DEBUG, CONFIG_IOMMU_DEBUG, and
CONFIG_IOMMU_LEAK.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
svcrdma's current SQ accounting algorithm takes sc_lock and disables
bottom-halves while posting all RDMA Read, Write, and Send WRs.
This is relatively heavyweight serialization. And note that Write and
Send are already fully serialized by the xpt_mutex.
Using a single atomic_t should be all that is necessary to guarantee
that ib_post_send() is called only when there is enough space on the
send queue. This is what the other RDMA-enabled storage targets do.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The current sendto code appears to support clients that provide only
one of a Read list, a Write list, or a Reply chunk. My reading of
that code is that it doesn't support the following cases:
- Read list + Write list
- Read list + Reply chunk
- Write list + Reply chunk
- Read list + Write list + Reply chunk
The protocol allows more than one Read or Write chunk in those
lists. Some clients do send a Read list and Reply chunk
simultaneously. NFSv4 WRITE uses a Read list for the data payload,
and a Reply chunk because the GETATTR result in the reply can
contain a large object like an ACL.
Generalize one of the sendto code paths needed to support all of
the above cases, and attempt to ensure that only one pass is done
through the RPC Call's transport header to gather chunk list
information for building the reply.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Joonyoung Shim reported an interesting problem on his ARM octa-core
Odoroid-XU3 platform. During system suspend, dev_pm_opp_put_regulator()
was failing for a struct device for which dev_pm_opp_set_regulator() is
called earlier.
This happened because an earlier call to
dev_pm_opp_of_cpumask_remove_table() function (from cpufreq-dt.c file)
removed all the entries from opp_table->dev_list apart from the last CPU
device in the cpumask of CPUs sharing the OPP.
But both dev_pm_opp_set_regulator() and dev_pm_opp_put_regulator()
routines get CPU device for the first CPU in the cpumask. And so the OPP
core failed to find the OPP table for the struct device.
This patch attempts to fix this problem by returning a pointer to the
opp_table from dev_pm_opp_set_regulator() and using that as the
parameter to dev_pm_opp_put_regulator(). This ensures that the
dev_pm_opp_put_regulator() doesn't fail to find the opp table.
Note that similar design problem also exists with other
dev_pm_opp_put_*() APIs, but those aren't used currently by anyone and
so we don't need to update them for now.
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Reported-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ Viresh: Wrote commit log and tested on exynos 5250 ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The driver needs to maintain several FW/HW-indices for each one of
its queues. Currently, that mapping is done by the QED where it uses
an rx/tx array of so-called hw-cids, populating them whenever a new
queue is opened and clearing them upon destruction of said queues.
This maintenance is far from ideal - there's no real reason why
QED needs to maintain such a data-structure. It becomes even worse
when considering the fact that the PF's queues and its child VFs' queues
are all mapped into the same data-structure.
As a by-product, the set of parameters an interface needs to supply for
queue APIs is non-trivial, and some of the variables in the API
structures have different meaning depending on their exact place
in the configuration flow.
This patch re-organizes the way L2 queues are configured and maintained.
In short:
- Required parameters for queue init are now well-defined.
- Qed would allocate a queue-cid based on parameters.
Upon initialization success, it would return a handle to caller.
- Queue-handle would be maintained by entity requesting queue-init,
not necessarily qed.
- All further queue-APIs [update, destroy] would use the opaque
handle as reference for the queue instead of various indices.
The possible owners of such handles:
- PF queues [qede] - complete handles based on provided configuration.
- VF queues [qede] - fw-context-less handles, containing only relative
information; Only the PF-side would need the absolute indices
for configuration, so they're omitted here.
- VF queues [qed, PF-side] - complete handles based on VF initialization.
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The chain structure and functions are widely used by the qed* modules,
both for configuration and datapath.
E.g., qede's Tx has one such chain and its Rx has two.
Currently, the strucutre's fields which are required for datapath
related functions [produce/consume] are intertwined with fields which
are required only for configuration purposes [init/destroy/etc.].
This patch re-arranges the chain structure so that all the fields which
are required for datapath usage could reside in a single cacheline instead
of the two which are required today.
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set the .enabled boolean and trigger an event processing when enabling
for edge-triggered systems.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Merge "ARM: keystone: add TI SCI protocol support for v4.10" from
Tero Kristo:
[description taken from http://processors.wiki.ti.com/index.php/TISCI
Texas Instruments' Keystone generation System on Chips (SoC) starting
with 66AK2G02, now include a dedicated SoC System Control entity called
PMMC(Power Management Micro Controller) in line with ARM architecture
recommendations. The function of this module is to integrate all system
operations in a centralized location. Communication with the SoC System
Control entity from various processing units like ARM/DSP occurs over
Message Manager hardware block.
...
Texas Instruments' System Control Interface defines the communication
protocol between various processing entities to the System Control Entity
on TI SoCs. This is a set of message formats and sequence of operations
required to communicate and get system services processed from System
Control entity in the SoC.]
* 'for-4.10-ti-sci-base' of https://github.com/t-kristo/linux-pm:
firmware: ti_sci: Add support for reboot core service
firmware: ti_sci: Add support for Clock control
firmware: ti_sci: Add support for Device control
firmware: Add basic support for TI System Control Interface (TI-SCI) protocol
Documentation: Add support for TI System Control Interface (TI-SCI) protocol
Pull "soc_device_match() interface for matching against soc_bus attributes"
from Geert Uytterhoeven:
This provides core infrastructure as a dependency for several users
(Freescale/NXP, Samsung, Renesas).
Its core parts have been acked by Greg, and the fixes by Arnd and/or
Greg (the last fix only received an informal ack, that's why I hadn't
added the ack).
This has already been pulled by Ulf, and is present in mmc/next, as a
dependency for a Freescale/NXP driver update.
* tag 'soc-device-match-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers:
base: soc: Provide a dummy implementation of soc_device_match()
base: soc: Check for NULL SoC device attributes
base: soc: Introduce soc_device_match() interface
base: soc: Early register bus when needed
Add an IFLA_XDP_FLAGS attribute that can be passed for setting up
XDP along with IFLA_XDP_FD, which eventually allows user space to
implement typical add/replace/delete logic for programs. Right now,
calling into dev_change_xdp_fd() will always replace previous programs.
When passed XDP_FLAGS_UPDATE_IF_NOEXIST, we can handle this more
graceful when requested by returning -EBUSY in case we try to
attach a new program, but we find that another one is already
attached. This will be used by upcoming front-end for iproute2 as
well.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Broadcom PHYs expose a number of PHY error counters: receive errors,
false carrier sense, SerDes BER count, local and remote receive errors.
Add support code to allow retrieving these error counters. Since the
Broadcom PHY library code is used by several drivers, make it possible
for them to specify the storage for the software copy of the statistics.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch exports the sender chronograph stats via the socket
SO_TIMESTAMPING channel. Currently we can instrument how long a
particular application unit of data was queued in TCP by tracking
SOF_TIMESTAMPING_TX_SOFTWARE and SOF_TIMESTAMPING_TX_SCHED. Having
these sender chronograph stats exported simultaneously along with
these timestamps allow further breaking down the various sender
limitation. For example, a video server can tell if a particular
chunk of video on a connection takes a long time to deliver because
TCP was experiencing small receive window. It is not possible to
tell before this patch without packet traces.
To prepare these stats, the user needs to set
SOF_TIMESTAMPING_OPT_STATS and SOF_TIMESTAMPING_OPT_TSONLY flags
while requesting other SOF_TIMESTAMPING TX timestamps. When the
timestamps are available in the error queue, the stats are returned
in a separate control message of type SCM_TIMESTAMPING_OPT_STATS,
in a list of TLVs (struct nlattr) of types: TCP_NLA_BUSY_TIME,
TCP_NLA_RWND_LIMITED, TCP_NLA_SNDBUF_LIMITED. Unit is microsecond.
Signed-off-by: Francis Yan <francisyyan@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements the skeleton of the TCP chronograph
instrumentation on sender side limits:
1) idle (unspec)
2) busy sending data other than 3-4 below
3) rwnd-limited
4) sndbuf-limited
The limits are enumerated 'tcp_chrono'. Since a connection in
theory can idle forever, we do not track the actual length of this
uninteresting idle period. For the rest we track how long the sender
spends in each limit. At any point during the life time of a
connection, the sender must be in one of the four states.
If there are multiple conditions worthy of tracking in a chronograph
then the highest priority enum takes precedence over
the other conditions. So that if something "more interesting"
starts happening, stop the previous chrono and start a new one.
The time unit is jiffy(u32) in order to save space in tcp_sock.
This implies application must sample the stats no longer than every
49 days of 1ms jiffy.
Signed-off-by: Francis Yan <francisyyan@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kexec_locate_mem_hole will be used by the PowerPC kexec_file_load
implementation to find free memory for the purgatory stack.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This is done to simplify the kexec_add_buffer argument list.
Adapt all callers to set up a kexec_buf to pass to kexec_add_buffer.
In addition, change the type of kexec_buf.buffer from char * to void *.
There is no particular reason for it to be a char *, and the change
allows us to get rid of 3 existing casts to char * in the code.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Allow architectures to specify a different memory walking function for
kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but
PowerPC uses the memblock subsystem.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The only places that were grabbing dqonoff_mutex are functions turning
quotas on and off and these are properly serialized using s_umount
semaphore. Remove dqonoff_mutex.
Signed-off-by: Jan Kara <jack@suse.cz>
drm/virtio: fix busid in a different way, allocate more vbufs.
drm/qxl: various bugfixes and cleanups,
* tag 'drm-qemu-20161121' of git://git.kraxel.org/linux: (224 commits)
drm/virtio: allocate some extra bufs
qxl: Allow resolution which are not multiple of 8
qxl: Don't notify userspace when monitors config is unchanged
qxl: Remove qxl_bo_init() return value
qxl: Call qxl_gem_{init, fini}
qxl: Add missing '\n' to qxl_io_log() call
qxl: Remove unused prototype
qxl: Mark some internal functions as static
Revert "drm: virtio: reinstate drm_virtio_set_busid()"
drm/virtio: fix busid regression
drm: re-export drm_dev_set_unique
Linux 4.9-rc5
gp8psk: Fix DVB frontend attach
gp8psk: fix gp8psk_usb_in_op() logic
dvb-usb: move data_mutex to struct dvb_usb_device
iio: maxim_thermocouple: detect invalid storage size in read()
aoe: fix crash in page count manipulation
lightnvm: invalid offset calculation for lba_shift
Kbuild: enable -Wmaybe-uninitialized warnings by default
pcmcia: fix return value of soc_pcmcia_regulator_set
...
Add helper to deregister fixed-link PHYs registered using
of_phy_register_fixed_link().
Convert the two drivers that care to deregister their fixed-link PHYs to
use the new helper, but note that most drivers currently fail to do so.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds a full fledget direct I/O implementation using the iomap
interface. Full fledged in this case means all features are supported:
AIO, vectored I/O, any iov_iter type including kernel pointers, bvecs
and pipes, support for hole filling and async apending writes. It does
not mean supporting all the warts of the old generic code. We expect
i_rwsem to be held over the duration of the call, and we expect to
maintain i_dio_count ourselves, and we pass on any kinds of mapping
to the file system for now.
The algorithm used is very simple: We use iomap_apply to iterate over
the range of the I/O, and then we use the new bio_iov_iter_get_pages
helper to lock down the user range for the size of the extent.
bio_iov_iter_get_pages can currently lock down twice as many pages as
the old direct I/O code did, which means that we will have a better
batch factor for everything but overwrites of badly fragmented files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kent Overstreet <kent.overstreet@gmail.com>
Tested-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
