kernel/git/stable/linux.git/drivers/dma/edma.c, branch linux-3.18.y

dmaengine: edma: fix memory leak when terminating running transfers

2015-04-24T21:13:53+00:00

[ Upstream commit 5ca9e7ce6eebec53362ff779264143860ccf68cd ] If edma_terminate_all() was called while a transfer was running (i.e. after edma_execute() but before edma_callback()) the echan->edesc was not freed. This was due to the fact that a running transfer is on none of the vchan lists: desc_submitted, desc_issued, desc_completed (edma_execute() removes it from the desc_issued list), so the vchan_dma_desc_free_list() called at the end of edma_terminate_all() didn't find it and didn't free it. This bug was found on an AM1808 based hardware (very similar to da850evm, however using the second MMC/SD controller), where intense operations on the SD card wasted the device 128MB RAM within a couple of days. Peter Ujfalusi: The issue is even more severe since it affects cyclic (audio) transfers as well. In this case starting/stopping audio will results memory leak. Signed-off-by: Petr Kulhavy Signed-off-by: Peter Ujfalusi CC: CC: Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

dma: edma: move device registration to platform code

2014-11-06T02:26:10+00:00

The horrible split between the low-level part of the edma support and the dmaengine front-end driver causes problems on multiplatform kernels. This is an attempt to improve the situation slightly by only registering the dmaengine devices that are actually present. Signed-off-by: Arnd Bergmann [olof: add missing include of linux/dma-mapping.h] Signed-off-by: Olof Johansson Signed-off-by: Olof Johansson

dmaengine: edma: check for echan->edesc => NULL in edma_dma_pause()

2014-10-15T15:25:04+00:00

I added book keeping of whether or not the 8250-dma driver has an RX transfer pending or not so we don't BUG here if it calls dmaengine_pause() on a channel which has not a pending transfer. Guess what, this is not enough. The following can be triggered with a busy RX channel and hackbench in background: - DMA transfer completes. The callback is delayed via vchan_cookie_complete() into a tasklet so it das not happen asap. - hackbench keeps the system busy so the tasklet does not run "soon". - the UART collected enough data and generates an "timeout"-interrupt. Since 8250-dma *thinks* the DMA-transfer is still pending it tries to cancel it via invoking dmaengine_pause() first. This causes the segfault because echan->edesc is NULL now that the transfer completed (however the callback did not run yet). With this patch we don't BUG in the scenario described. Signed-off-by: Sebastian Andrzej Siewior Acked-by: Peter Ujfalusi Signed-off-by: Vinod Koul

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

2014-08-11T14:14:01+00:00

Pull slave-dma updates from Vinod Koul: "Some notable changes are: - new driver for AMBA AXI NBPF by Guennadi - new driver for sun6i controller by Maxime - pl330 drivers fixes from Lar's - sh-dma updates and fixes from Laurent, Geert and Kuninori - Documentation updates from Geert - drivers fixes and updates spread over dw, edma, freescale, mpc512x etc.." * 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (72 commits) dmaengine: sun6i: depends on RESET_CONTROLLER dma: at_hdmac: fix invalid remaining bytes detection dmaengine: nbpfaxi: don't build this driver where it cannot be used dmaengine: nbpf_error_get_channel() can be static dma: pl08x: Use correct specifier for size_t values dmaengine: Remove the context argument to the prep_dma_cyclic operation dmaengine: nbpfaxi: convert to tasklet dmaengine: nbpfaxi: fix a theoretical race dmaengine: add a driver for AMBA AXI NBPF DMAC IP cores dmaengine: add device tree binding documentation for the nbpfaxi driver dmaengine: edma: Do not register second device when booted with DT dmaengine: edma: Do not change the error code returned from edma_alloc_slot dmaengine: rcar-dmac: Add device tree bindings documentation dmaengine: shdma: Allocate cyclic sg list dynamically dmaengine: shdma: Make channel filter ignore unrelated devices dmaengine: sh: Rework Kconfig and Makefile dmaengine: sun6i: Fix memory leaks dmaengine: sun6i: Free the interrupt before killing the tasklet dmaengine: sun6i: Remove switch statement from buswidth convertion routine dmaengine: of: kconfig: select DMA_ENGINE when DMA_OF is selected ...

dmaengine: Remove the context argument to the prep_dma_cyclic operation

2014-08-04T08:11:50+00:00

The argument is always set to NULL and never used. Remove it. Signed-off-by: Laurent Pinchart Signed-off-by: Vinod Koul

dmaengine: edma: Do not register second device when booted with DT

2014-07-31T11:57:47+00:00

DT boot does not yet support more than one edma device. To avoid issues at runtime we should not register the second device when the kernel is booted with DT. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul

dmaengine: edma: Do not change the error code returned from edma_alloc_slot

2014-07-31T11:57:47+00:00

In case of edma_alloc_slot() failure during probe we should return the error unchanged to make debugging easier. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul

dmaengine: edma: Serve cyclic (audio) channels with high priority queue

2014-07-28T11:33:16+00:00

Move the DMA channel used in cyclic mode (audio) to the highest priority event queue which helps to reduce audio problems. When the channel is terminated, move it back to the default queue. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul

dmaengine: edma: Support to suppress the period interrupts in cyclic mode

2014-07-28T11:32:53+00:00

If the client (audio) does not request interrupts for every period we can disable them. With updated audio driver stack we can play audio w/o the need to process any edma interrupts. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul

dmaengine: edma: Update caps->residue_granularity to match with reality

2014-07-28T11:32:33+00:00

The edma can report accurate DMA position so update the residue_granularity to DMA_RESIDUE_GRANULARITY_BURST. Signed-off-by: Peter Ujfalusi Signed-off-by: Vinod Koul