linux/Documentation
Takashi Iwai f274baa49b ALSA: usb-audio: Allow non-vmalloc buffer for PCM buffers
Currently, USB-audio driver allocates the PCM buffer via vmalloc(), as
this serves merely as an intermediate buffer that is copied to each
URB transfer buffer.  This works well in general on x86, but on some
archs this may result in cache coherency issues when mmap is used.
OTOH, it works also on such arch unless mmap is used.

This patch is a step for mitigating the inconvenience; a new module
option "use_vmalloc" is provided so that user can choose to allocate
the DMA coherent buffer instead of the existing vmalloc buffer.
The drawback is that it'd be the standard dma_alloc_coherent() calls
and the system would require contiguous pages on non-x86 archs.

Note that it's a global option and not dynamically switchable since
the buffer is pre-allocated at the probe time.  In theory, it's
possible to be switchable, but it'd be trickier and racier.

As default use_vmalloc option is set to true, so that the old behavior
is kept.  For allowing the coherent mmap on ARM or MIPS, pass
use_vmalloc=0 option explicitly.

Reported-and-tested-by: Daniel Danzberger <daniel@dd-wrt.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-29 10:01:54 +02:00
..
ABI RTC for 4.17 2018-04-10 10:22:27 -07:00
accelerators ocxl: Document the OCXL_IOCTL_GET_METADATA IOCTL 2018-03-02 13:02:15 +11:00
accounting
acpi
admin-guide ARM: 2018-04-09 11:42:31 -07:00
aoe
arm MTD changes: 2018-04-06 12:15:41 -07:00
arm64 ARM: 2018-04-09 11:42:31 -07:00
auxdisplay
backlight
block
blockdev
bpf bpf, doc: add description wrt native/bpf clang target and pointer size 2018-03-20 15:47:45 -07:00
bus-devices
cdrom Documentation/cdrom: fix German sharp s in LaTex 2018-03-08 19:35:29 -07:00
cgroup-v1 page cache: use xa_lock 2018-04-11 10:28:39 -07:00
cma
connector
console
core-api textsearch: fix kernel-doc warnings and add kernel-api section 2018-04-16 18:53:13 -04:00
cpu-freq cpufreq: Drop cpufreq_table_validate_and_show() 2018-04-10 08:40:45 +02:00
cpuidle cpuidle: Add definition of residency to sysfs documentation 2018-04-09 13:44:37 +02:00
crypto crypto: doc - clarify hash callbacks state machine 2018-03-31 01:33:02 +08:00
dev-tools There's been a fair amount of activity in Documentation/ this time around: 2018-04-03 13:35:51 -07:00
device-mapper dm verity: add 'check_at_most_once' option to only validate hashes once 2018-04-03 15:04:29 -04:00
devicetree Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal 2018-04-20 10:56:32 -07:00
doc-guide doc-guide: kernel-doc: add comment about formatting verification 2018-02-23 08:06:15 -07:00
driver-api MTD changes: 2018-04-06 12:15:41 -07:00
driver-model serdev: Introduce devm_serdev_device_open() 2018-01-08 10:08:34 +00:00
early-userspace
EDID
extcon
fault-injection Documentation: nvme: Documentation for nvme fault injection 2018-03-26 08:53:43 -06:00
fb
features arch: remove obsolete architecture ports 2018-04-02 20:20:12 -07:00
filesystems Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2018-04-13 16:55:41 -07:00
firmware_class
fmc
fpga
gpio Documentation: gpio: Move drivers-on-gpio.txt to driver-api 2018-03-23 04:22:29 +01:00
gpu Linux 4.16-rc7 2018-03-28 14:30:41 +10:00
hid
hwmon hwmon: (lm92) Add max6635 to lm92_id[] 2018-03-22 09:33:24 -07:00
i2c i2c: i801: Add missing documentation entries for Braswell and Kaby Lake 2018-02-21 09:17:20 +01:00
ia64 ia64: doc: tweak whitespace for 'console=' parameter 2018-03-05 14:41:38 -08:00
ide
iio
infiniband Documentation/ABI: update infiniband sysfs interfaces 2018-02-23 08:18:33 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2018-04-05 13:21:57 -07:00
ioctl arch: remove tile port 2018-03-16 10:56:03 +01:00
isdn Documentation/isdn: check and fix dead links ... 2018-03-26 12:31:13 -04:00
kbuild Kconfig updates for v4.17 2018-04-03 16:28:01 -07:00
kdump
kernel-hacking Documentation: Fix misconversion of #if 2018-01-17 16:45:01 -07:00
laptops
leds
lightnvm
livepatch livepatch: Allow to call a custom callback when freeing shadow variables 2018-04-17 13:42:48 +02:00
locking Linux 4.16-rc2 2018-02-21 09:57:55 +01:00
m68k
maintainer
md raid5-ppl: PPL support for disks with write-back cache enabled 2018-01-15 14:29:42 -08:00
media media: extended-controls.rst: transmitter -> receiver 2018-04-04 08:05:20 -04:00
memory-devices
mic
mips Documentation: mips: Update AU1xxx_IDE Kconfig dependencies 2018-02-01 12:45:35 -07:00
misc-devices
mmc
mtd
namespaces
netlabel
networking docs: ip-sysctl.txt: fix name of some ipv6 variables 2018-04-19 15:20:09 -04:00
nfc
nios2
nvdimm
nvmem
openrisc
parisc
PCI PCI: Update location of pci.ids file 2018-02-22 15:00:43 -06:00
pcmcia
perf drivers/bus: Move Arm CCN PMU driver 2018-03-06 17:26:15 +01:00
phy
platform
power PM / hibernate: Make passing hibernate offsets more friendly 2018-03-30 12:01:20 +02:00
powerpc
pps
process Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-15 16:12:35 -07:00
pti
ptp ptp: Fix documentation to match code. 2018-03-26 12:13:21 -04:00
rapidio Documentation: rapidio: move sysfs interface to ABI 2018-02-23 08:25:45 -07:00
RCU
s390 vfio-ccw: update documentation 2018-03-01 17:32:14 +01:00
scheduler
scsi scsi: documentation: Obsolete documentation references 2018-03-21 18:34:20 -04:00
security selinux: Update SELinux SCTP documentation 2018-03-20 16:26:15 -04:00
serial
sh
sound ALSA: usb-audio: Allow non-vmalloc buffer for PCM buffers 2018-05-29 10:01:54 +02:00
sparc sparc64: Add support for ADI (Application Data Integrity) 2018-03-18 07:38:48 -07:00
sphinx Documentation/sphinx: Fix Directive import error 2018-03-09 10:46:14 -07:00
sphinx-static
spi
sysctl taint: add taint for randstruct 2018-04-11 10:28:35 -07:00
target
thermal thermal: Add cooling device's statistics in sysfs 2018-04-02 21:49:01 +08:00
timers sched/isolation: Eliminate NO_HZ_FULL_ALL 2018-02-15 15:40:37 -08:00
trace New features: 2018-04-10 11:27:30 -07:00
translations Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2018-02-01 13:36:15 -08:00
usb Documentation updates for 4.16. New stuff includes refcount_t 2018-01-31 19:25:25 -08:00
userspace-api
virtual KVM: trivial documentation cleanups 2018-03-28 22:47:06 +02:00
vm page cache: use xa_lock 2018-04-11 10:28:39 -07:00
w1 Documentation updates for 4.16. New stuff includes refcount_t 2018-01-31 19:25:25 -08:00
watchdog watchdog: remove bfin_wdt driver 2018-03-26 15:57:04 +02:00
wimax
x86 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-15 16:12:35 -07:00
xtensa
.gitignore
00-INDEX CRIS: Drop support for the CRIS port 2018-03-16 10:56:05 +01:00
atomic_bitops.txt locking/atomic/bitops: Document and clarify ordering semantics for failed test_and_{}_bit() 2018-02-13 14:55:53 +01:00
atomic_t.txt
bcache.txt
bt8xxgpio.txt
btmrvl.txt
bus-virt-phys-mapping.txt
cachetlb.txt
cgroup-v2.txt cgroup, docs: document the root cgroup behavior of cpu and io controllers 2018-01-16 08:07:09 -08:00
Changes
circular-buffers.txt
clearing-warn-once.txt
clk.txt Documentation: clk: enable lock is not held for clk_is_enabled API 2018-03-16 15:44:43 -07:00
CodingStyle
conf.py
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt
DMA-ISA-LPC.txt
docutils.conf
dontdiff
efi-stub.txt
eisa.txt
flexible-arrays.txt
futex-requeue-pi.txt
gcc-plugins.txt
highuid.txt
hw_random.txt
hwspinlock.txt
index.rst Documentation: add Linux tracing to Sphinx TOC tree 2018-03-07 10:22:53 -07:00
intel_txt.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt irqdomain: Kill CONFIG_IRQ_DOMAIN_DEBUG 2018-01-24 12:32:58 +01:00
IRQ.txt
irqflags-tracing.txt
isa.txt
isapnp.txt
kernel-per-CPU-kthreads.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
lockup-watchdogs.txt
logo.gif
logo.txt
lsm.txt
lzo.txt
mailbox.txt
Makefile
memory-barriers.txt locking/memory-barriers: De-emphasize smp_read_barrier_depends() some more 2018-03-10 10:22:22 +01:00
memory-hotplug.txt
men-chameleon-bus.txt
nommu-mmap.txt
ntb.txt
numastat.txt
padata.txt
parport-lowlevel.txt
percpu-rw-semaphore.txt
phy.txt
pi-futex.txt
pnp.txt
preempt-locking.txt
pwm.txt
rbtree.txt
remoteproc.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rtc.txt Documentation: rtc: move iotcl interface documentation to ABI 2018-01-12 00:20:41 +01:00
SAK.txt
sgi-ioc4.txt
siphash.txt
SM501.txt
smsc_ece1099.txt
speculation.txt Documentation: Document array_index_nospec 2018-01-30 21:54:28 +01:00
static-keys.txt
SubmittingPatches
svga.txt
switchtec.txt
sync_file.txt
tee.txt
this_cpu_ops.txt
unaligned-memory-access.txt
vfio-mediated-device.txt
vfio.txt
video-output.txt
xillybus.txt
xz.txt
zorro.txt