| Message ID | 20190607030719.77286-4-john.stultz@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | DMA-BUF Heaps (destaging ION) | expand |
Hi, On Fri, Jun 07, 2019 at 03:07:17AM +0000, John Stultz wrote: > This patch adds system heap to the dma-buf heaps framework. > > This allows applications to get a page-allocator backed dma-buf > for non-contiguous memory. > > This code is an evolution of the Android ION implementation, so > thanks to its original authors and maintainters: > Rebecca Schultz Zavin, Colin Cross, Laura Abbott, and others! > > Cc: Laura Abbott <labbott@redhat.com> > Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org> > Cc: Sumit Semwal <sumit.semwal@linaro.org> > Cc: Liam Mark <lmark@codeaurora.org> > Cc: Pratik Patel <pratikp@codeaurora.org> > Cc: Brian Starkey <Brian.Starkey@arm.com> > Cc: Vincent Donnefort <Vincent.Donnefort@arm.com> > Cc: Sudipto Paul <Sudipto.Paul@arm.com> > Cc: Andrew F. Davis <afd@ti.com> > Cc: Christoph Hellwig <hch@infradead.org> > Cc: Chenbo Feng <fengc@google.com> > Cc: Alistair Strachan <astrachan@google.com> > Cc: dri-devel@lists.freedesktop.org > Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> > Signed-off-by: John Stultz <john.stultz@linaro.org> > Change-Id: I4dc5ff54ccb1f7ca3ac8675661114ca33813654b > --- > v2: > * Switch allocate to return dmabuf fd > * Simplify init code > * Checkpatch fixups > * Droped dead system-contig code > v3: > * Whitespace fixups from Benjamin > * Make sure we're zeroing the allocated pages (from Liam) > * Use PAGE_ALIGN() consistently (suggested by Brian) > * Fold in new registration style from Andrew > * Avoid needless dynamic allocation of sys_heap (suggested by > Christoph) > * Minor cleanups > * Folded in changes from Andrew to use simplified page list > from the heap helpers > v4: > * Optimization to allocate pages in chunks, similar to old > pagepool code > * Use fd_flags when creating dmabuf fd (Suggested by Benjamin) > v5: > * Back out large order page allocations (was leaking memory, > as the page array didn't properly track order size) > --- > drivers/dma-buf/Kconfig | 2 + > drivers/dma-buf/heaps/Kconfig | 6 ++ > drivers/dma-buf/heaps/Makefile | 1 + > drivers/dma-buf/heaps/system_heap.c | 123 ++++++++++++++++++++++++++++ > 4 files changed, 132 insertions(+) > create mode 100644 drivers/dma-buf/heaps/Kconfig > create mode 100644 drivers/dma-buf/heaps/system_heap.c > > diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig > index 9b93f86f597c..434cfe646dad 100644 > --- a/drivers/dma-buf/Kconfig > +++ b/drivers/dma-buf/Kconfig > @@ -47,4 +47,6 @@ menuconfig DMABUF_HEAPS > this allows userspace to allocate dma-bufs that can be shared between > drivers. > > +source "drivers/dma-buf/heaps/Kconfig" > + > endmenu > diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig > new file mode 100644 > index 000000000000..205052744169 > --- /dev/null > +++ b/drivers/dma-buf/heaps/Kconfig > @@ -0,0 +1,6 @@ > +config DMABUF_HEAPS_SYSTEM > + bool "DMA-BUF System Heap" > + depends on DMABUF_HEAPS > + help > + Choose this option to enable the system dmabuf heap. The system heap > + is backed by pages from the buddy allocator. If in doubt, say Y. > diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile > index de49898112db..d1808eca2581 100644 > --- a/drivers/dma-buf/heaps/Makefile > +++ b/drivers/dma-buf/heaps/Makefile > @@ -1,2 +1,3 @@ > # SPDX-License-Identifier: GPL-2.0 > obj-y += heap-helpers.o > +obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o > diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c > new file mode 100644 > index 000000000000..863834499ce1 > --- /dev/null > +++ b/drivers/dma-buf/heaps/system_heap.c > @@ -0,0 +1,123 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * DMABUF System heap exporter > + * > + * Copyright (C) 2011 Google, Inc. > + * Copyright (C) 2019 Linaro Ltd. > + */ > + > +#include <asm/page.h> > +#include <linux/dma-buf.h> > +#include <linux/dma-mapping.h> > +#include <linux/dma-heap.h> > +#include <linux/err.h> > +#include <linux/highmem.h> > +#include <linux/mm.h> > +#include <linux/scatterlist.h> > +#include <linux/slab.h> > + > +#include "heap-helpers.h" > + > +struct system_heap { > + struct dma_heap *heap; > +} sys_heap; > + > + extra newline. Otherwise, LGTM: Reviewed-by: Brian Starkey <brian.starkey@arm.com>
diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig index 9b93f86f597c..434cfe646dad 100644 --- a/drivers/dma-buf/Kconfig +++ b/drivers/dma-buf/Kconfig @@ -47,4 +47,6 @@ menuconfig DMABUF_HEAPS this allows userspace to allocate dma-bufs that can be shared between drivers. +source "drivers/dma-buf/heaps/Kconfig" + endmenu diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig new file mode 100644 index 000000000000..205052744169 --- /dev/null +++ b/drivers/dma-buf/heaps/Kconfig @@ -0,0 +1,6 @@ +config DMABUF_HEAPS_SYSTEM + bool "DMA-BUF System Heap" + depends on DMABUF_HEAPS + help + Choose this option to enable the system dmabuf heap. The system heap + is backed by pages from the buddy allocator. If in doubt, say Y. diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile index de49898112db..d1808eca2581 100644 --- a/drivers/dma-buf/heaps/Makefile +++ b/drivers/dma-buf/heaps/Makefile @@ -1,2 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 obj-y += heap-helpers.o +obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c new file mode 100644 index 000000000000..863834499ce1 --- /dev/null +++ b/drivers/dma-buf/heaps/system_heap.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMABUF System heap exporter + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ + +#include <asm/page.h> +#include <linux/dma-buf.h> +#include <linux/dma-mapping.h> +#include <linux/dma-heap.h> +#include <linux/err.h> +#include <linux/highmem.h> +#include <linux/mm.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> + +#include "heap-helpers.h" + +struct system_heap { + struct dma_heap *heap; +} sys_heap; + + +static void system_heap_free(struct heap_helper_buffer *buffer) +{ + pgoff_t pg; + + for (pg = 0; pg < buffer->pagecount; pg++) + __free_page(buffer->pages[pg]); + kfree(buffer->pages); + kfree(buffer); +} + +static int system_heap_allocate(struct dma_heap *heap, + unsigned long len, + unsigned long fd_flags, + unsigned long heap_flags) +{ + struct heap_helper_buffer *helper_buffer; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + unsigned long size_remaining = len; + struct dma_buf *dmabuf; + int ret = -ENOMEM; + pgoff_t pg; + + helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL); + if (!helper_buffer) + return -ENOMEM; + + INIT_HEAP_HELPER_BUFFER(helper_buffer, system_heap_free); + helper_buffer->heap_buffer.flags = heap_flags; + helper_buffer->heap_buffer.heap = heap; + helper_buffer->heap_buffer.size = len; + + helper_buffer->pagecount = len / PAGE_SIZE; + helper_buffer->pages = kmalloc_array(helper_buffer->pagecount, + sizeof(*helper_buffer->pages), + GFP_KERNEL); + if (!helper_buffer->pages) { + ret = -ENOMEM; + goto err0; + } + + for (pg = 0; pg < helper_buffer->pagecount; pg++) { + helper_buffer->pages[pg] = alloc_page(GFP_KERNEL | __GFP_ZERO); + if (!helper_buffer->pages[pg]) + goto err1; + } + + /* create the dmabuf */ + exp_info.ops = &heap_helper_ops; + exp_info.size = len; + exp_info.flags = fd_flags; + exp_info.priv = &helper_buffer->heap_buffer; + dmabuf = dma_buf_export(&exp_info); + if (IS_ERR(dmabuf)) { + ret = PTR_ERR(dmabuf); + goto err1; + } + + helper_buffer->heap_buffer.dmabuf = dmabuf; + + ret = dma_buf_fd(dmabuf, fd_flags); + if (ret < 0) { + dma_buf_put(dmabuf); + /* just return, as put will call release and that will free */ + return ret; + } + + return ret; + +err1: + while (pg > 0) + __free_page(helper_buffer->pages[--pg]); + kfree(helper_buffer->pages); +err0: + kfree(helper_buffer); + + return -ENOMEM; +} + +static struct dma_heap_ops system_heap_ops = { + .allocate = system_heap_allocate, +}; + +static int system_heap_create(void) +{ + struct dma_heap_export_info exp_info; + int ret = 0; + + exp_info.name = "system_heap"; + exp_info.ops = &system_heap_ops; + exp_info.priv = &sys_heap; + + sys_heap.heap = dma_heap_add(&exp_info); + if (IS_ERR(sys_heap.heap)) + ret = PTR_ERR(sys_heap.heap); + + return ret; +} +device_initcall(system_heap_create);