linux-stable/drivers/base
Stephen Boyd 9ccf981198 firmware: consolidate kmap/read/write logic
Some systems are memory constrained but they need to load very large
firmwares.  The firmware subsystem allows drivers to request this
firmware be loaded from the filesystem, but this requires that the
entire firmware be loaded into kernel memory first before it's provided
to the driver.  This can lead to a situation where we map the firmware
twice, once to load the firmware into kernel memory and once to copy the
firmware into the final resting place.

This design creates needless memory pressure and delays loading because
we have to copy from kernel memory to somewhere else.  This patch sets
adds support to the request firmware API to load the firmware directly
into a pre-allocated buffer, skipping the intermediate copying step and
alleviating memory pressure during firmware loading.  The drawback is
that we can't use the firmware caching feature because the memory for
the firmware cache is not managed by the firmware layer.

This patch (of 3):

We use similar structured code to read and write the kmapped firmware
pages.  The only difference is read copies from the kmap region and
write copies to it.  Consolidate this into one function to reduce
duplication.

Link: http://lkml.kernel.org/r/20160607164741.31849-2-stephen.boyd@linaro.org
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Vikram Mulukutla <markivx@codeaurora.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:09 -04:00
..
power Merge branches 'pm-core', 'pm-clk', 'pm-domains' and 'pm-pci' 2016-07-25 13:45:27 +02:00
regmap Merge remote-tracking branches 'regmap/topic/bulk', 'regmap/topic/i2c', 'regmap/topic/iopoll', 'regmap/topic/irq' and 'regmap/topic/maintainers' into regmap-next 2016-07-15 13:44:47 +01:00
attribute_container.c
base.h
bus.c
cacheinfo.c
class.c
component.c
container.c
core.c
cpu.c
dd.c Revert "base: dd: don't remove driver_data in -EPROBE_DEFER case" 2016-05-03 08:06:06 -07:00
devcoredump.c devcoredump: add scatterlist support 2016-04-15 11:20:32 -07:00
devres.c
devtmpfs.c
dma-coherent.c drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings 2016-03-22 15:36:02 -07:00
dma-contiguous.c
dma-mapping.c
driver.c
firmware.c
firmware_class.c firmware: consolidate kmap/read/write logic 2016-08-02 19:35:09 -04:00
hypervisor.c
init.c
isa.c isa: Call isa_bus_init before dependent ISA bus drivers register 2016-06-17 20:47:11 -07:00
Kconfig
Makefile isa: Allow ISA-style drivers on modern systems 2016-06-17 20:21:12 -07:00
map.c
memory.c memory-hotplug: use zone_can_shift() for sysfs valid_zones attribute 2016-07-26 16:19:19 -07:00
module.c base: make module_create_drivers_dir race-free 2016-06-15 19:21:31 -07:00
node.c treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
pinctrl.c
platform-msi.c
platform.c device property: don't bother the drivers with struct property_set 2016-04-09 03:10:50 +02:00
property.c device property: Add function to search for named child of device 2016-06-26 12:39:03 +01:00
soc.c
syscore.c
topology.c topology/sysfs: provide drawer id and siblings attributes 2016-06-13 15:58:27 +02:00
transport_class.c