Reference counting is done at the module level so clients need not worry
that a channel will leave while they are actively using dmaengine.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
All users have been converted to either the general-purpose allocator,
dma_find_channel, or dma_request_channel.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that clients no longer need to be notified of channel arrival
dma_async_client_register can simply increment the dmaengine_ref_count.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
dma_request_channel provides an exclusive channel, so we no longer need to
pass slave data through dmaengine.
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Replace the client registration infrastructure with a custom loop to
poll for channels. Once dma_request_channel returns NULL stop asking
for channels. A userspace side effect of this change if that loading
the dmatest module before loading a dma driver will result in no
channels being found, previously dmatest would get a callback. To
facilitate testing in the built-in case dmatest_init is marked as a
late_initcall. Another side effect is that channels under test can not
be used for any other purpose.
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This interface is primarily for device-to-memory clients which need to
search for dma channels with platform-specific characteristics. The
prototype is:
struct dma_chan *dma_request_channel(dma_cap_mask_t mask,
dma_filter_fn filter_fn,
void *filter_param);
When the optional 'filter_fn' parameter is set to NULL
dma_request_channel simply returns the first channel that satisfies the
capability mask. Otherwise, when the mask parameter is insufficient for
specifying the necessary channel, the filter_fn routine can be used to
disposition the available channels in the system. The filter_fn routine
is called once for each free channel in the system. Upon seeing a
suitable channel filter_fn returns DMA_ACK which flags that channel to
be the return value from dma_request_channel. A channel allocated via
this interface is exclusive to the caller, until dma_release_channel()
is called.
To ensure that all channels are not consumed by the general-purpose
allocator the DMA_PRIVATE capability is provided to exclude a dma_device
from general-purpose (memory-to-memory) consideration.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
async_tx and net_dma each have open-coded versions of issue_pending_all,
so provide a common routine in dmaengine.
The implementation needs to walk the global device list, so implement
rcu to allow dma_issue_pending_all to run lockless. Clients protect
themselves from channel removal events by holding a dmaengine reference.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Allowing multiple clients to each define their own channel allocation
scheme quickly leads to a pathological situation. For memory-to-memory
offload all clients can share a central allocator.
This simply moves the existing async_tx allocator to dmaengine with
minimal fixups:
* async_tx.c:get_chan_ref_by_cap --> dmaengine.c:nth_chan
* async_tx.c:async_tx_rebalance --> dmaengine.c:dma_channel_rebalance
* split out common code from async_tx.c:__async_tx_find_channel -->
dma_find_channel
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Simply, if a client wants any dmaengine channel then prevent all dmaengine
modules from being removed. Once the clients are done re-enable module
removal.
Why?, beyond reducing complication:
1/ Tracking reference counts per-transaction in an efficient manner, as
is currently done, requires a complicated scheme to avoid cache-line
bouncing effects.
2/ Per-transaction ref-counting gives the false impression that a
dma-driver can be gracefully removed ahead of its user (net, md, or
dma-slave)
3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but
if such an engine were built one day we still would not need to notify
clients of remove events. The driver can simply return NULL to a
->prep() request, something that is much easier for a client to handle.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
async_tx.ko is a consumer of dma channels. A circular dependency arises
if modules in drivers/dma rely on common code in async_tx.ko. It
prevents either module from being unloaded.
Move dma_wait_for_async_tx and async_tx_run_dependencies to dmaeninge.o
where they should have been from the beginning.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add standard interfaces for alarm/update irqs enabling. Drivers are no
more required to implement equivalent ioctl code as rtc-dev will provide
it.
UIE emulation should now be handled correctly and will work even for those
RTC drivers who cannot be configured to do both UIE and AIE.
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The function viafb_cursor() uses 2 stack-variables of CURSOR_SIZE bits;
CURSOR_SIZE is defined as (8 * 1024). Using up twice 1k on stack is too
much for 4k-stack (though it works with 8k-stacks). Make those two
variables kzalloc'ed to preserve stack space.
Also merge the whole lot of local struct's in viafb_ioctl into a union so
the stack usage gets minimized here as well. (struct's are only accessed
in their indicidual IOCTL case) This second part is only compile-tested as
I know of no userspace app using the IOCTLs.
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Cc: <JosephChan@via.com.tw>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (77 commits)
x86: setup_per_cpu_areas() cleanup
cpumask: fix compile error when CONFIG_NR_CPUS is not defined
cpumask: use alloc_cpumask_var_node where appropriate
cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t
x86: use cpumask_var_t in acpi/boot.c
x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids
sched: put back some stack hog changes that were undone in kernel/sched.c
x86: enable cpus display of kernel_max and offlined cpus
ia64: cpumask fix for is_affinity_mask_valid()
cpumask: convert RCU implementations, fix
xtensa: define __fls
mn10300: define __fls
m32r: define __fls
h8300: define __fls
frv: define __fls
cris: define __fls
cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
cpumask: zero extra bits in alloc_cpumask_var_node
cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/
cpumask: convert mm/
...
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (34 commits)
V4L/DVB (10173): Missing v4l2_prio_close in radio_release
V4L/DVB (10172): add DVB_DEVICE_TYPE= to uevent
V4L/DVB (10171): Use usb_set_intfdata
V4L/DVB (10170): tuner-simple: prevent possible OOPS caused by divide by zero error
V4L/DVB (10168): sms1xxx: fix inverted gpio for lna control on tiger r2
V4L/DVB (10167): sms1xxx: add support for inverted gpio
V4L/DVB (10166): dvb frontend: stop using non-C99 compliant comments
V4L/DVB (10165): Add FE_CAN_2G_MODULATION flag to frontends that support DVB-S2
V4L/DVB (10164): Add missing S2 caps flag to S2API
V4L/DVB (10163): em28xx: allocate adev together with struct em28xx dev
V4L/DVB (10162): tuner-simple: Fix tuner type set message
V4L/DVB (10161): saa7134: fix autodetection for AVer TV GO 007 FM Plus
V4L/DVB (10160): em28xx: update chip id for em2710
V4L/DVB (10157): Add USB ID for the Sil4701 radio from DealExtreme
V4L/DVB (10156): saa7134: Add support for Avermedia AVer TV GO 007 FM Plus
V4L/DVB (10155): Add TEA5764 radio driver
V4L/DVB (10154): saa7134: fix a merge conflict on Behold H6 board
V4L/DVB (10153): Add the Beholder H6 card to DVB-T part of sources.
V4L/DVB (10152): Change configuration of the Beholder H6 card
V4L/DVB (10151): Fix I2C bridge error in zl10353
...
those two functions only used in that C file
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
mmc: warn about voltage mismatches
mmc_spi: Add support for OpenFirmware bindings
pxamci: fix dma_unmap_sg length
mmc_block: ensure all sectors that do not have errors are read
drivers/mmc: Move a dereference below a NULL test
sdhci: handle built-in sdhci with modular leds class
mmc: balanc pci_iomap with pci_iounmap
mmc_block: print better error messages
mmc: Add mmc_vddrange_to_ocrmask() helper function
ricoh_mmc: Handle newer models of Ricoh controllers
mmc: Add 8-bit bus width support
sdhci: activate led support also when module
mmc: trivial annotation of 'blocks'
pci: use pci_ioremap_bar() in drivers/mmc
sdricoh_cs: Add support for Bay Controller devices
mmc: at91_mci: reorder timer setup and mmc_add_host() call
CONFIG_NR_CPUS will be defined for all arch's whether SMP or not, but
it may not have made it into all arches yet.
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Reduce memory usage, use new API.
This is part of an effort to reduce structure sizes for machines
configured with large NR_CPUS. cpumask_t gets replaced by
cpumask_var_t, which is either struct cpumask[1] (small NR_CPUS) or
struct cpumask * (large NR_CPUS).
(Changes to powernow-k* by <travis>.)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
These two IOMMUs can implement the current version of this API. So
select the API if one or both of these IOMMU drivers is selected.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This API can be used by KVM for accessing different types of IOMMUs to
do device passthrough to guests. Beside that this API can also be used
by device drivers to map non-linear host memory into dma-linear
addresses to prevent sgather-gather DMA. UIO may be another user for
this API.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
When domain is related to multiple iommus, need to check if the minimum agaw is sufficient for the mapped memory
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
vm_domid won't be set in context, find available domain id for a device from its iommu.
For a virtual machine domain, a default agaw will be set, and skip top levels of page tables for iommu which has less agaw than default.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
virtual machine domain is different from native DMA-API domain, implement separate allocation and free functions for virtual machine domain.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Because virtual machine domain may have multiple devices from different iommus, it cannot use __iommu_flush_cache.
In some common low level functions, use domain_flush_cache instead of __iommu_flush_cache. On the other hand, in some functions, iommu can is specified or domain cannot be got, still use __iommu_flush_cache
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Add iommu reference count in domain, and add a lock to protect iommu setting including iommu_bmp, iommu_count and iommu_coherency.
virtual machine domain may have multiple devices from different iommus, so it needs to do more things when add/remove domain device info. Thus implement separate these functions for virtual machine domain.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Add this flag for VT-d used in virtual machine, like KVM.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
In dmar_domain, more than one iommus may be included in iommu_bmp. Due to "Coherency" capability may be different across iommus, set this variable to indicate iommu access is coherent or not. Only when all related iommus in a dmar_domain are all coherent, iommu access of this domain is coherent.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
"SAGAW" capability may be different across iommus. Use a default agaw, but if default agaw is not supported in some iommus, choose a less supported agaw.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
In order to support assigning multiple devices from different iommus to a domain, iommu bitmap is used to keep all iommus the domain are related to.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
deferred_flush[] uses the iommu seq_id to index, so its iommu is fixed and can get it from g_iommus.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
It's random number after the domain is allocated by kmem_cache_alloc
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The radio_release function of the BTTV driver is missing a call to
v4l2_prio_close. As a result, after the radio device has been opened at
least once (e.g., by HAL during bootup), v4l2_priority will never drop below
V4L2_PRIORITY_INTERACTIVE again. With the following patch against 2.6.28,
applications that run with V4L2_PRIORITY_BACKGROUND are able to open devices
again. Previous Linux versions are affected as well.
Signed-off-by: Udo Steinberg <udo@hypervisor.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This code had calls to both usb_set_intfdata and dev_set_drvdata, doing the
same thing.
The semantic patch that lead to finding this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@header@
@@
@same depends on header@
position p;
@@
usb_set_intfdata@p(...) { ... }
@depends on header@
position _p!=same.p;
identifier _f;
struct usb_interface *intf;
expression data;
@@
_f@_p(...) { <+...
- dev_set_drvdata(&intf->dev, data);
+ usb_set_intfdata(intf, data);
...+> }
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
On platforms with multiple PCI segments, any of the segments can have a DRHD
with INCLUDE_PCI_ALL flag. So need to check the DRHD's segment number against
the PCI device's when searching its DRHD.
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
