linux.git/drivers/dma/Kconfig, branch v3.13

net_dma: mark broken

2013-12-18T20:53:43+00:00

net_dma can cause data to be copied to a stale mapping if a
copy-on-write fault occurs during dma.  The application sees missing
data.

The following trace is triggered by modifying the kernel to WARN if it
ever triggers copy-on-write on a page that is undergoing dma:

 WARNING: CPU: 24 PID: 2529 at lib/dma-debug.c:485 debug_dma_assert_idle+0xd2/0x120()
 ioatdma 0000:00:04.0: DMA-API: cpu touching an active dma mapped page [pfn=0x16bcd9]
 Modules linked in: iTCO_wdt iTCO_vendor_support ioatdma lpc_ich pcspkr dca
 CPU: 24 PID: 2529 Comm: linbug Tainted: G        W    3.13.0-rc1+ #353
  00000000000001e5 ffff88016f45f688 ffffffff81751041 ffff88017ab0ef70
  ffff88016f45f6d8 ffff88016f45f6c8 ffffffff8104ed9c ffffffff810f3646
  ffff8801768f4840 0000000000000282 ffff88016f6cca10 00007fa2bb699349
 Call Trace:
  [] dump_stack+0x46/0x58
  [] warn_slowpath_common+0x8c/0xc0
  [] ? ftrace_pid_func+0x26/0x30
  [] warn_slowpath_fmt+0x46/0x50
  [] debug_dma_assert_idle+0xd2/0x120
  [] do_wp_page+0xd0/0x790
  [] handle_mm_fault+0x51c/0xde0
  [] ? copy_user_enhanced_fast_string+0x9/0x20
  [] __do_page_fault+0x19c/0x530
  [] ? _raw_spin_lock_bh+0x16/0x40
  [] ? trace_clock_local+0x9/0x10
  [] ? rb_reserve_next_event+0x64/0x310
  [] ? ioat2_dma_prep_memcpy_lock+0x60/0x130 [ioatdma]
  [] do_page_fault+0xe/0x10
  [] page_fault+0x22/0x30
  [] ? __kfree_skb+0x51/0xd0
  [] ? copy_user_enhanced_fast_string+0x9/0x20
  [] ? memcpy_toiovec+0x52/0xa0
  [] skb_copy_datagram_iovec+0x5f/0x2a0
  [] tcp_rcv_established+0x674/0x7f0
  [] tcp_v4_do_rcv+0x2e5/0x4a0
  [..]
 ---[ end trace e30e3b01191b7617 ]---
 Mapped at:
  [] debug_dma_map_page+0xb9/0x160
  [] dma_async_memcpy_pg_to_pg+0x127/0x210
  [] dma_memcpy_pg_to_iovec+0x119/0x1f0
  [] dma_skb_copy_datagram_iovec+0x11c/0x2b0
  [] tcp_rcv_established+0x74a/0x7f0:

...the problem is that the receive path falls back to cpu-copy in
several locations and this trace is just one of the areas.  A few
options were considered to fix this:

1/ sync all dma whenever a cpu copy branch is taken

2/ modify the page fault handler to hold off while dma is in-flight

Option 1 adds yet more cpu overhead to an "offload" that struggles to compete
with cpu-copy.  Option 2 adds checks for behavior that is already documented as
broken when using get_user_pages().  At a minimum a debug mode is warranted to
catch and flag these violations of the dma-api vs get_user_pages().

Thanks to David for his reproducer.

Cc: 
Cc: Dave Jiang 
Cc: Vinod Koul 
Cc: Alexander Duyck 
Reported-by: David Whipple 
Acked-by: David S. Miller 
Signed-off-by: Dan Williams

dmaengine: fix enable for high order unmap pools

2013-12-13T06:43:42+00:00

The higher order mempools support raid operations, and we want to
disable them when raid support is not enabled.  Making them conditional
on ASYNC_TX_DMA is not sufficient as other users (specifically dmatest)
will also issue raid operations.  Make raid drivers explicitly request
that the core carry the higher order pools.

Reported-by: Ezequiel Garcia 
Tested-by: Ezequiel Garcia 
Signed-off-by: Dan Williams

Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma

2013-11-20T21:20:24+00:00

Pull slave-dmaengine changes from Vinod Koul:
 "This brings for slave dmaengine:

   - Change dma notification flag to DMA_COMPLETE from DMA_SUCCESS as
     dmaengine can only transfer and not verify validaty of dma
     transfers

   - Bunch of fixes across drivers:

      - cppi41 driver fixes from Daniel

      - 8 channel freescale dma engine support and updated bindings from
        Hongbo

      - msx-dma fixes and cleanup by Markus

   - DMAengine updates from Dan:

      - Bartlomiej and Dan finalized a rework of the dma address unmap
        implementation.

      - In the course of testing 1/ a collection of enhancements to
        dmatest fell out.  Notably basic performance statistics, and
        fixed / enhanced test control through new module parameters
        'run', 'wait', 'noverify', and 'verbose'.  Thanks to Andriy and
        Linus [Walleij] for their review.

      - Testing the raid related corner cases of 1/ triggered bugs in
        the recently added 16-source operation support in the ioatdma
        driver.

      - Some minor fixes / cleanups to mv_xor and ioatdma"

* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (99 commits)
  dma: mv_xor: Fix mis-usage of mmio 'base' and 'high_base' registers
  dma: mv_xor: Remove unneeded NULL address check
  ioat: fix ioat3_irq_reinit
  ioat: kill msix_single_vector support
  raid6test: add new corner case for ioatdma driver
  ioatdma: clean up sed pool kmem_cache
  ioatdma: fix selection of 16 vs 8 source path
  ioatdma: fix sed pool selection
  ioatdma: Fix bug in selftest after removal of DMA_MEMSET.
  dmatest: verbose mode
  dmatest: convert to dmaengine_unmap_data
  dmatest: add a 'wait' parameter
  dmatest: add basic performance metrics
  dmatest: add support for skipping verification and random data setup
  dmatest: use pseudo random numbers
  dmatest: support xor-only, or pq-only channels in tests
  dmatest: restore ability to start test at module load and init
  dmatest: cleanup redundant "dmatest: " prefixes
  dmatest: replace stored results mechanism, with uniform messages
  Revert "dmatest: append verify result to results"
  ...

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2013-11-16T00:47:22+00:00

Pull trivial tree updates from Jiri Kosina:
 "Usual earth-shaking, news-breaking, rocket science pile from
  trivial.git"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
  doc: add missing files to timers/00-INDEX
  timekeeping: Fix some trivial typos in comments
  mm: Fix some trivial typos in comments
  irq: Fix some trivial typos in comments
  NUMA: fix typos in Kconfig help text
  mm: update 00-INDEX
  doc: Documentation/DMA-attributes.txt fix typo
  DRM: comment: `halve' -> `half'
  Docs: Kconfig: `devlopers' -> `developers'
  doc: typo on word accounting in kprobes.c in mutliple architectures
  treewide: fix "usefull" typo
  treewide: fix "distingush" typo
  mm/Kconfig: Grammar s/an/a/
  kexec: Typo s/the/then/
  Documentation/kvm: Update cpuid documentation for steal time and pv eoi
  treewide: Fix common typo in "identify"
  __page_to_pfn: Fix typo in comment
  Correct some typos for word frequency
  clk: fixed-factor: Fix a trivial typo
  ...

DMA: Freescale: update driver to support 8-channel DMA engine

2013-11-13T08:56:27+00:00

This patch adds support to 8-channel DMA engine, thus the driver works for both
the new 8-channel and the legacy 4-channel DMA engines.

Signed-off-by: Hongbo Zhang 
Signed-off-by: Vinod Koul

Merge tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

2013-11-11T08:05:37+00:00

Pull ARM driver updates from Olof Johansson:
 "Updates of SoC-near drivers and other driver updates that makes more
  sense to take through our tree.  In this case it's involved:

   - Some Davinci driver updates that has required corresponding
     platform code changes (gpio mostly)
   - CCI bindings and a few driver updates
   - Marvell mvebu patches for PCI MSI support (could have gone through
     the PCI tree for this release, but they were acked by Bjorn for
     3.12 so we kept them through arm-soc).
   - Marvell dove switch-over to DT-based PCIe configuration
   - Misc updates for Samsung platform dmaengine drivers"

* tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (32 commits)
  ARM: S3C24XX: add dma pdata for s3c2410, s3c2440 and s3c2442
  dmaengine: s3c24xx-dma: add support for the s3c2410 type of controller
  ARM: S3C24XX: Fix possible dma selection warning
  PCI: mvebu: make local functions static
  PCI: mvebu: add I/O access wrappers
  PCI: mvebu: Dynamically detect if the PEX link is up to enable hot plug
  ARM: mvebu: fix gated clock documentation
  ARM: dove: remove legacy pcie and clock init
  ARM: dove: switch to DT probed mbus address windows
  ARM: SAMSUNG: set s3c24xx_dma_filter for s3c64xx-spi0 device
  ARM: S3C24XX: add platform-devices for new dma driver for s3c2412 and s3c2443
  dmaengine: add driver for Samsung s3c24xx SoCs
  ARM: S3C24XX: number the dma clocks
  PCI: mvebu: add support for Marvell Dove SoCs
  PCI: mvebu: add support for reset on GPIO
  PCI: mvebu: remove subsys_initcall
  PCI: mvebu: increment nports only for registered ports
  PCI: mvebu: move clock enable before register access
  PCI: mvebu: add support for MSI
  irqchip: armada-370-xp: implement MSI support
  ...

treewide: Fix typo in Kconfig

2013-10-14T13:23:02+00:00

Correct spelling typo in Kconfig.

Signed-off-by: Masanari Iida 
Acked-by: Randy Dunlap 
Signed-off-by: Jiri Kosina

dma: Allow TI_EDMA selectable for ARCH_KEYSTONE

2013-10-10T23:52:18+00:00

Allow the TI_EDMA to be built for ARCH_KEYSTONE which also supports
the EDMA IP.

Acked-by: Vinod Koul 
Signed-off-by: Santosh Shilimkar

dmaengine: add driver for Samsung s3c24xx SoCs

2013-10-07T21:42:10+00:00

This adds a new driver to support the s3c24xx dma using the dmaengine
and makes the old one in mach-s3c24xx obsolete in the long run.

Conceptually the s3c24xx-dma feels like a distant relative of the pl08x
with numerous virtual channels being mapped to a lot less physical ones.
The driver therefore borrows a lot from the amba-pl08x driver in this
regard. Functionality-wise the driver gains a memcpy ability in addition
to the slave_sg one.

The driver supports both the method for requesting the peripheral used
by SoCs before the S3C2443 and the different method for S3C2443 and later.

On earlier SoCs the hardware channels usable for specific peripherals is
constrainted while on later SoCs all channels can be used for any peripheral.

Tested on a s3c2416-based board, memcpy using the dmatest module and
slave_sg partially using the spi-s3c64xx driver.

Signed-off-by: Heiko Stuebner 
Acked-by: Linus Walleij 
Acked-by: Vinod Koul 
Signed-off-by: Kukjin Kim

dma/Kconfig: Make TI_EDMA select TI_PRIV_EDMA

2013-09-17T04:56:22+00:00

The TI_EDMA driver unconditionally calls functions provided by the
TI_PRIV_EDMA code, but it doesn't force that to be built-in.  If that isn't
otherwise enabled somewhere, you can get build errors like:

linux-3.12.0-0.rc0.git1.1.fc21.armv7hl/drivers/dma/edma.c:593: undefined reference to `edma_free_slot'
drivers/built-in.o: In function `edma_terminate_all':
linux-3.12.0-0.rc0.git1.1.fc21.armv7hl/drivers/dma/edma.c:169: undefined reference to `edma_stop'
drivers/built-in.o: In function `edma_execute':
linux-3.12.0-0.rc0.git1.1.fc21.armv7hl/drivers/dma/edma.c:122: undefined reference to `edma_write_slot'
linux-3.12.0-0.rc0.git1.1.fc21.armv7hl/drivers/dma/edma.c:149: undefined reference to `edma_link'
linux-3.12.0-0.rc0.git1.1.fc21.armv7hl/drivers/dma/edma.c:152: undefined reference to `edma_start'

Make TI_EDMA select TI_PRIV_EDMA to avoid this.

Signed-off-by: Josh Boyer 
Acked-by: Matt Porter 
Signed-off-by: Vinod Koul