Here is another RFC of the dma-buf heaps patchset Andrew and I
have been working on which tries to destage a fair chunk of ION
functionality.
The patchset implements per-heap devices which can be opened
directly and then an ioctl is used to allocate a dmabuf from the
heap.
The interface is similar, but much simpler then IONs, only
providing an ALLOC ioctl.
Also, I've provided relatively simple system and cma heaps.
I've booted and tested these patches with AOSP on the HiKey960
using the kernel tree here:
https://git.linaro.org/people/john.stultz/android-dev.git/log/?h=dev/dma-buf-heap
And the userspace changes here:
https://android-review.googlesource.com/c/device/linaro/hikey/+/909436
Compared to ION, this patchset is missing the system-contig,
carveout and chunk heaps, as I don't have a device that uses
those, so I'm unable to do much useful validation there.
Additionally we have no upstream users of chunk or carveout,
and the system-contig has been deprecated in the common/andoid-*
kernels, so this should be ok.
I've also removed the stats accounting for now, since any such
accounting should be implemented by dma-buf core or the heaps
themselves.
New in v4:
* Add fd_flags per Benjamin's request to specify the creation
flags for the dmabuf fd.
* Added some optimization in the system heap to allocate
contiguous pages where possible.
* Reworked the kselftest code to use vgem rather then
introducing a dummy importer
* Other cleanups suggested by Benjamin and Andrew.
Outstanding concerns:
* Need to better understand various secure heap implementations.
Some concern that heap private flags will be needed, but its
also possible that dma-buf heaps can't solve everyone's needs,
in which case, a vendor's secure buffer driver can implement
their own dma-buf exporter.
* Making sure the performance issues from potentially
unnecessary cache-management operations can be resolved
properly for system and cma heaps(outstanding issue from ION).
That said, the main user-interface is shaping up and I wanted
to get some input on the device model (particularly from GreKH)
and any other API/ABI specific input.
thanks
-john
Cc: Laura Abbott <[email protected]>
Cc: Benjamin Gaignard <[email protected]>
Cc: Sumit Semwal <[email protected]>
Cc: Liam Mark <[email protected]>
Cc: Pratik Patel <[email protected]>
Cc: Brian Starkey <[email protected]>
Cc: Vincent Donnefort <[email protected]>
Cc: Sudipto Paul <[email protected]>
Cc: Andrew F. Davis <[email protected]>
Cc: Xu YiPing <[email protected]>
Cc: "Chenfeng (puck)" <[email protected]>
Cc: butao <[email protected]>
Cc: "Xiaqing (A)" <[email protected]>
Cc: Yudongbin <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Chenbo Feng <[email protected]>
Cc: Alistair Strachan <[email protected]>
Cc: [email protected]
Andrew F. Davis (1):
dma-buf: Add dma-buf heaps framework
John Stultz (4):
dma-buf: heaps: Add heap helpers
dma-buf: heaps: Add system heap to dmabuf heaps
dma-buf: heaps: Add CMA heap to dmabuf heaps
kselftests: Add dma-heap test
MAINTAINERS | 18 ++
drivers/dma-buf/Kconfig | 10 +
drivers/dma-buf/Makefile | 2 +
drivers/dma-buf/dma-heap.c | 241 ++++++++++++++++
drivers/dma-buf/heaps/Kconfig | 14 +
drivers/dma-buf/heaps/Makefile | 4 +
drivers/dma-buf/heaps/cma_heap.c | 169 ++++++++++++
drivers/dma-buf/heaps/heap-helpers.c | 261 ++++++++++++++++++
drivers/dma-buf/heaps/heap-helpers.h | 55 ++++
drivers/dma-buf/heaps/system_heap.c | 162 +++++++++++
include/linux/dma-heap.h | 59 ++++
include/uapi/linux/dma-heap.h | 56 ++++
tools/testing/selftests/dmabuf-heaps/Makefile | 11 +
.../selftests/dmabuf-heaps/dmabuf-heap.c | 232 ++++++++++++++++
14 files changed, 1294 insertions(+)
create mode 100644 drivers/dma-buf/dma-heap.c
create mode 100644 drivers/dma-buf/heaps/Kconfig
create mode 100644 drivers/dma-buf/heaps/Makefile
create mode 100644 drivers/dma-buf/heaps/cma_heap.c
create mode 100644 drivers/dma-buf/heaps/heap-helpers.c
create mode 100644 drivers/dma-buf/heaps/heap-helpers.h
create mode 100644 drivers/dma-buf/heaps/system_heap.c
create mode 100644 include/linux/dma-heap.h
create mode 100644 include/uapi/linux/dma-heap.h
create mode 100644 tools/testing/selftests/dmabuf-heaps/Makefile
create mode 100644 tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c
--
2.17.1
Add generic helper dmabuf ops for dma heaps, so we can reduce
the amount of duplicative code for the exported dmabufs.
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 <[email protected]>
Cc: Benjamin Gaignard <[email protected]>
Cc: Sumit Semwal <[email protected]>
Cc: Liam Mark <[email protected]>
Cc: Pratik Patel <[email protected]>
Cc: Brian Starkey <[email protected]>
Cc: Vincent Donnefort <[email protected]>
Cc: Sudipto Paul <[email protected]>
Cc: Andrew F. Davis <[email protected]>
Cc: Xu YiPing <[email protected]>
Cc: "Chenfeng (puck)" <[email protected]>
Cc: butao <[email protected]>
Cc: "Xiaqing (A)" <[email protected]>
Cc: Yudongbin <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Chenbo Feng <[email protected]>
Cc: Alistair Strachan <[email protected]>
Cc: [email protected]
Signed-off-by: John Stultz <[email protected]>
---
v2:
* Removed cache management performance hack that I had
accidentally folded in.
* Removed stats code that was in helpers
* Lots of checkpatch cleanups
v3:
* Uninline INIT_HEAP_HELPER_BUFFER (suggested by Christoph)
* Switch to WARN on buffer destroy failure (suggested by Brian)
* buffer->kmap_cnt decrementing cleanup (suggested by Christoph)
* Extra buffer->vaddr checking in dma_heap_dma_buf_kmap
(suggested by Brian)
* Switch to_helper_buffer from macro to inline function
(suggested by Benjamin)
* Rename kmap->vmap (folded in from Andrew)
* Use vmap for vmapping - not begin_cpu_access (folded in from
Andrew)
* Drop kmap for now, as its optional (folded in from Andrew)
* Fold dma_heap_map_user into the single caller (foled in from
Andrew)
* Folded in patch from Andrew to track page list per heap not
sglist, which simplifies the tracking logic
v4:
* Moved dma-heap.h change out to previous patch
---
drivers/dma-buf/Makefile | 1 +
drivers/dma-buf/heaps/Makefile | 2 +
drivers/dma-buf/heaps/heap-helpers.c | 261 +++++++++++++++++++++++++++
drivers/dma-buf/heaps/heap-helpers.h | 55 ++++++
4 files changed, 319 insertions(+)
create mode 100644 drivers/dma-buf/heaps/Makefile
create mode 100644 drivers/dma-buf/heaps/heap-helpers.c
create mode 100644 drivers/dma-buf/heaps/heap-helpers.h
diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile
index b0332f143413..09c2f2db9cf4 100644
--- a/drivers/dma-buf/Makefile
+++ b/drivers/dma-buf/Makefile
@@ -1,4 +1,5 @@
obj-y := dma-buf.o dma-fence.o dma-fence-array.o reservation.o seqno-fence.o
+obj-$(CONFIG_DMABUF_HEAPS) += heaps/
obj-$(CONFIG_DMABUF_HEAPS) += dma-heap.o
obj-$(CONFIG_SYNC_FILE) += sync_file.o
obj-$(CONFIG_SW_SYNC) += sw_sync.o sync_debug.o
diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile
new file mode 100644
index 000000000000..de49898112db
--- /dev/null
+++ b/drivers/dma-buf/heaps/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y += heap-helpers.o
diff --git a/drivers/dma-buf/heaps/heap-helpers.c b/drivers/dma-buf/heaps/heap-helpers.c
new file mode 100644
index 000000000000..00cbdbbb97e5
--- /dev/null
+++ b/drivers/dma-buf/heaps/heap-helpers.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/device.h>
+#include <linux/dma-buf.h>
+#include <linux/err.h>
+#include <linux/idr.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/dma-heap.h>
+
+#include "heap-helpers.h"
+
+void INIT_HEAP_HELPER_BUFFER(struct heap_helper_buffer *buffer,
+ void (*free)(struct heap_helper_buffer *))
+{
+ buffer->private_flags = 0;
+ buffer->priv_virt = NULL;
+ mutex_init(&buffer->lock);
+ buffer->vmap_cnt = 0;
+ buffer->vaddr = NULL;
+ INIT_LIST_HEAD(&buffer->attachments);
+ buffer->free = free;
+}
+
+
+static void *dma_heap_map_kernel(struct heap_helper_buffer *buffer)
+{
+ void *vaddr;
+
+ vaddr = vmap(buffer->pages, buffer->pagecount, VM_MAP, PAGE_KERNEL);
+ if (!vaddr)
+ return ERR_PTR(-ENOMEM);
+
+ return vaddr;
+}
+
+void dma_heap_buffer_destroy(struct dma_heap_buffer *heap_buffer)
+{
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+
+ if (buffer->vmap_cnt > 0) {
+ WARN("%s: buffer still mapped in the kernel\n",
+ __func__);
+ vunmap(buffer->vaddr);
+ }
+
+ buffer->free(buffer);
+}
+
+static void *dma_heap_buffer_vmap_get(struct dma_heap_buffer *heap_buffer)
+{
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+ void *vaddr;
+
+ if (buffer->vmap_cnt) {
+ buffer->vmap_cnt++;
+ return buffer->vaddr;
+ }
+ vaddr = dma_heap_map_kernel(buffer);
+ if (WARN_ONCE(!vaddr,
+ "heap->ops->map_kernel should return ERR_PTR on error"))
+ return ERR_PTR(-EINVAL);
+ if (IS_ERR(vaddr))
+ return vaddr;
+ buffer->vaddr = vaddr;
+ buffer->vmap_cnt++;
+ return vaddr;
+}
+
+static void dma_heap_buffer_vmap_put(struct dma_heap_buffer *heap_buffer)
+{
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+
+ if (!--buffer->vmap_cnt) {
+ vunmap(buffer->vaddr);
+ buffer->vaddr = NULL;
+ }
+}
+
+struct dma_heaps_attachment {
+ struct device *dev;
+ struct sg_table table;
+ struct list_head list;
+};
+
+static int dma_heap_attach(struct dma_buf *dmabuf,
+ struct dma_buf_attachment *attachment)
+{
+ struct dma_heaps_attachment *a;
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+ int ret;
+
+ a = kzalloc(sizeof(*a), GFP_KERNEL);
+ if (!a)
+ return -ENOMEM;
+
+ ret = sg_alloc_table_from_pages(&a->table, buffer->pages,
+ buffer->pagecount, 0,
+ buffer->pagecount << PAGE_SHIFT,
+ GFP_KERNEL);
+ if (ret) {
+ kfree(a);
+ return ret;
+ }
+
+ a->dev = attachment->dev;
+ INIT_LIST_HEAD(&a->list);
+
+ attachment->priv = a;
+
+ mutex_lock(&buffer->lock);
+ list_add(&a->list, &buffer->attachments);
+ mutex_unlock(&buffer->lock);
+
+ return 0;
+}
+
+static void dma_heap_detatch(struct dma_buf *dmabuf,
+ struct dma_buf_attachment *attachment)
+{
+ struct dma_heaps_attachment *a = attachment->priv;
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+
+ mutex_lock(&buffer->lock);
+ list_del(&a->list);
+ mutex_unlock(&buffer->lock);
+
+ sg_free_table(&a->table);
+ kfree(a);
+}
+
+static struct sg_table *dma_heap_map_dma_buf(
+ struct dma_buf_attachment *attachment,
+ enum dma_data_direction direction)
+{
+ struct dma_heaps_attachment *a = attachment->priv;
+ struct sg_table *table;
+
+ table = &a->table;
+
+ if (!dma_map_sg(attachment->dev, table->sgl, table->nents,
+ direction))
+ table = ERR_PTR(-ENOMEM);
+ return table;
+}
+
+static void dma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
+ struct sg_table *table,
+ enum dma_data_direction direction)
+{
+ dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);
+}
+
+static vm_fault_t dma_heap_vm_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct heap_helper_buffer *buffer = vma->vm_private_data;
+
+ vmf->page = buffer->pages[vmf->pgoff];
+ get_page(vmf->page);
+
+ return 0;
+}
+
+static const struct vm_operations_struct dma_heap_vm_ops = {
+ .fault = dma_heap_vm_fault,
+};
+
+static int dma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
+{
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+
+ if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
+ return -EINVAL;
+
+ vma->vm_ops = &dma_heap_vm_ops;
+ vma->vm_private_data = buffer;
+
+ return 0;
+}
+
+static void dma_heap_dma_buf_release(struct dma_buf *dmabuf)
+{
+ struct dma_heap_buffer *buffer = dmabuf->priv;
+
+ dma_heap_buffer_destroy(buffer);
+}
+
+static int dma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
+ enum dma_data_direction direction)
+{
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+ struct dma_heaps_attachment *a;
+ int ret = 0;
+
+ mutex_lock(&buffer->lock);
+ list_for_each_entry(a, &buffer->attachments, list) {
+ dma_sync_sg_for_cpu(a->dev, a->table.sgl, a->table.nents,
+ direction);
+ }
+ mutex_unlock(&buffer->lock);
+
+ return ret;
+}
+
+static int dma_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
+ enum dma_data_direction direction)
+{
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+ struct dma_heaps_attachment *a;
+
+ mutex_lock(&buffer->lock);
+ list_for_each_entry(a, &buffer->attachments, list) {
+ dma_sync_sg_for_device(a->dev, a->table.sgl, a->table.nents,
+ direction);
+ }
+ mutex_unlock(&buffer->lock);
+
+ return 0;
+}
+
+void *dma_heap_dma_buf_vmap(struct dma_buf *dmabuf)
+{
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+ void *vaddr;
+
+ mutex_lock(&buffer->lock);
+ vaddr = dma_heap_buffer_vmap_get(heap_buffer);
+ mutex_unlock(&buffer->lock);
+
+ return vaddr;
+}
+
+void dma_heap_dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr)
+{
+ struct dma_heap_buffer *heap_buffer = dmabuf->priv;
+ struct heap_helper_buffer *buffer = to_helper_buffer(heap_buffer);
+
+ mutex_lock(&buffer->lock);
+ dma_heap_buffer_vmap_put(heap_buffer);
+ mutex_unlock(&buffer->lock);
+}
+
+const struct dma_buf_ops heap_helper_ops = {
+ .map_dma_buf = dma_heap_map_dma_buf,
+ .unmap_dma_buf = dma_heap_unmap_dma_buf,
+ .mmap = dma_heap_mmap,
+ .release = dma_heap_dma_buf_release,
+ .attach = dma_heap_attach,
+ .detach = dma_heap_detatch,
+ .begin_cpu_access = dma_heap_dma_buf_begin_cpu_access,
+ .end_cpu_access = dma_heap_dma_buf_end_cpu_access,
+ .vmap = dma_heap_dma_buf_vmap,
+ .vunmap = dma_heap_dma_buf_vunmap,
+};
diff --git a/drivers/dma-buf/heaps/heap-helpers.h b/drivers/dma-buf/heaps/heap-helpers.h
new file mode 100644
index 000000000000..a17502dc22e3
--- /dev/null
+++ b/drivers/dma-buf/heaps/heap-helpers.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * DMABUF Heaps helper code
+ *
+ * Copyright (C) 2011 Google, Inc.
+ * Copyright (C) 2019 Linaro Ltd.
+ */
+
+#ifndef _HEAP_HELPERS_H
+#define _HEAP_HELPERS_H
+
+#include <linux/dma-heap.h>
+#include <linux/list.h>
+
+/**
+ * struct dma_heap_buffer - metadata for a particular buffer
+ * @heap: back pointer to the heap the buffer came from
+ * @dmabuf: backing dma-buf for this buffer
+ * @size: size of the buffer
+ * @flags: buffer specific flags
+ */
+struct dma_heap_buffer {
+ struct dma_heap *heap;
+ struct dma_buf *dmabuf;
+ size_t size;
+ unsigned long flags;
+};
+
+struct heap_helper_buffer {
+ struct dma_heap_buffer heap_buffer;
+
+ unsigned long private_flags;
+ void *priv_virt;
+ struct mutex lock;
+ int vmap_cnt;
+ void *vaddr;
+ pgoff_t pagecount;
+ struct page **pages;
+ struct list_head attachments;
+
+ void (*free)(struct heap_helper_buffer *buffer);
+
+};
+
+static inline struct heap_helper_buffer *to_helper_buffer(
+ struct dma_heap_buffer *h)
+{
+ return container_of(h, struct heap_helper_buffer, heap_buffer);
+}
+
+void INIT_HEAP_HELPER_BUFFER(struct heap_helper_buffer *buffer,
+ void (*free)(struct heap_helper_buffer *));
+extern const struct dma_buf_ops heap_helper_ops;
+
+#endif /* _HEAP_HELPERS_H */
--
2.17.1
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 <[email protected]>
Cc: Benjamin Gaignard <[email protected]>
Cc: Sumit Semwal <[email protected]>
Cc: Liam Mark <[email protected]>
Cc: Pratik Patel <[email protected]>
Cc: Brian Starkey <[email protected]>
Cc: Vincent Donnefort <[email protected]>
Cc: Sudipto Paul <[email protected]>
Cc: Andrew F. Davis <[email protected]>
Cc: Xu YiPing <[email protected]>
Cc: "Chenfeng (puck)" <[email protected]>
Cc: butao <[email protected]>
Cc: "Xiaqing (A)" <[email protected]>
Cc: Yudongbin <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Chenbo Feng <[email protected]>
Cc: Alistair Strachan <[email protected]>
Cc: [email protected]
Reviewed-by: Benjamin Gaignard <[email protected]>
Signed-off-by: John Stultz <[email protected]>
---
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)
---
drivers/dma-buf/Kconfig | 2 +
drivers/dma-buf/heaps/Kconfig | 6 ++
drivers/dma-buf/heaps/Makefile | 1 +
drivers/dma-buf/heaps/system_heap.c | 162 ++++++++++++++++++++++++++++
4 files changed, 171 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 8344cdaaa328..e34b6e61b702 100644
--- a/drivers/dma-buf/Kconfig
+++ b/drivers/dma-buf/Kconfig
@@ -46,4 +46,6 @@ 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..60ee531e1a24
--- /dev/null
+++ b/drivers/dma-buf/heaps/system_heap.c
@@ -0,0 +1,162 @@
+// 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;
+
+
+#define NUM_ORDERS ARRAY_SIZE(orders)
+#define HIGH_ORDER_GFP (((GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN \
+ | __GFP_NORETRY) & ~__GFP_RECLAIM) \
+ | __GFP_COMP)
+#define LOW_ORDER_GFP (GFP_HIGHUSER | __GFP_ZERO | __GFP_COMP)
+static gfp_t order_flags[] = {HIGH_ORDER_GFP, LOW_ORDER_GFP, LOW_ORDER_GFP};
+static const unsigned int orders[] = {8, 4, 0};
+
+
+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 struct page *alloc_largest_available(unsigned long size,
+ unsigned int max_order)
+{
+ struct page *page;
+ int i;
+
+ for (i = 0; i < NUM_ORDERS; i++) {
+ if (size < (PAGE_SIZE << orders[i]))
+ continue;
+ if (max_order < orders[i])
+ continue;
+
+ page = alloc_pages(order_flags[i], orders[i]);
+ if (!page)
+ continue;
+ return page;
+ }
+ return NULL;
+}
+
+
+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;
+ unsigned int max_order = orders[0];
+ 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;
+ }
+
+ pg = 0;
+ while (size_remaining > 0) {
+ struct page *page = alloc_largest_available(size_remaining,
+ max_order);
+ int i;
+
+ if (!page)
+ goto err1;
+ size_remaining -= PAGE_SIZE << compound_order(page);
+ max_order = compound_order(page);
+ for (i = 0; i < 1 << max_order; i++)
+ helper_buffer->pages[pg++] = page++;
+ }
+
+ /* 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);
--
2.17.1
Le lun. 13 mai 2019 à 20:37, John Stultz <[email protected]> a écrit :
>
> Here is another RFC of the dma-buf heaps patchset Andrew and I
> have been working on which tries to destage a fair chunk of ION
> functionality.
>
> The patchset implements per-heap devices which can be opened
> directly and then an ioctl is used to allocate a dmabuf from the
> heap.
>
> The interface is similar, but much simpler then IONs, only
> providing an ALLOC ioctl.
>
> Also, I've provided relatively simple system and cma heaps.
>
> I've booted and tested these patches with AOSP on the HiKey960
> using the kernel tree here:
> https://git.linaro.org/people/john.stultz/android-dev.git/log/?h=dev/dma-buf-heap
>
> And the userspace changes here:
> https://android-review.googlesource.com/c/device/linaro/hikey/+/909436
>
> Compared to ION, this patchset is missing the system-contig,
> carveout and chunk heaps, as I don't have a device that uses
> those, so I'm unable to do much useful validation there.
> Additionally we have no upstream users of chunk or carveout,
> and the system-contig has been deprecated in the common/andoid-*
> kernels, so this should be ok.
>
> I've also removed the stats accounting for now, since any such
> accounting should be implemented by dma-buf core or the heaps
> themselves.
>
>
> New in v4:
> * Add fd_flags per Benjamin's request to specify the creation
> flags for the dmabuf fd.
> * Added some optimization in the system heap to allocate
> contiguous pages where possible.
> * Reworked the kselftest code to use vgem rather then
> introducing a dummy importer
> * Other cleanups suggested by Benjamin and Andrew.
>
>
> Outstanding concerns:
> * Need to better understand various secure heap implementations.
> Some concern that heap private flags will be needed, but its
> also possible that dma-buf heaps can't solve everyone's needs,
> in which case, a vendor's secure buffer driver can implement
> their own dma-buf exporter.
> * Making sure the performance issues from potentially
> unnecessary cache-management operations can be resolved
> properly for system and cma heaps(outstanding issue from ION).
>
>
> That said, the main user-interface is shaping up and I wanted
> to get some input on the device model (particularly from GreKH)
> and any other API/ABI specific input.
>
For the whole series:
Reviewed-by: Benjamin Gaignard <[email protected]>
Thanks,
Benjamin
> thanks
> -john
>
>
> Cc: Laura Abbott <[email protected]>
> Cc: Benjamin Gaignard <[email protected]>
> Cc: Sumit Semwal <[email protected]>
> Cc: Liam Mark <[email protected]>
> Cc: Pratik Patel <[email protected]>
> Cc: Brian Starkey <[email protected]>
> Cc: Vincent Donnefort <[email protected]>
> Cc: Sudipto Paul <[email protected]>
> Cc: Andrew F. Davis <[email protected]>
> Cc: Xu YiPing <[email protected]>
> Cc: "Chenfeng (puck)" <[email protected]>
> Cc: butao <[email protected]>
> Cc: "Xiaqing (A)" <[email protected]>
> Cc: Yudongbin <[email protected]>
> Cc: Christoph Hellwig <[email protected]>
> Cc: Chenbo Feng <[email protected]>
> Cc: Alistair Strachan <[email protected]>
> Cc: [email protected]
>
> Andrew F. Davis (1):
> dma-buf: Add dma-buf heaps framework
>
> John Stultz (4):
> dma-buf: heaps: Add heap helpers
> dma-buf: heaps: Add system heap to dmabuf heaps
> dma-buf: heaps: Add CMA heap to dmabuf heaps
> kselftests: Add dma-heap test
>
> MAINTAINERS | 18 ++
> drivers/dma-buf/Kconfig | 10 +
> drivers/dma-buf/Makefile | 2 +
> drivers/dma-buf/dma-heap.c | 241 ++++++++++++++++
> drivers/dma-buf/heaps/Kconfig | 14 +
> drivers/dma-buf/heaps/Makefile | 4 +
> drivers/dma-buf/heaps/cma_heap.c | 169 ++++++++++++
> drivers/dma-buf/heaps/heap-helpers.c | 261 ++++++++++++++++++
> drivers/dma-buf/heaps/heap-helpers.h | 55 ++++
> drivers/dma-buf/heaps/system_heap.c | 162 +++++++++++
> include/linux/dma-heap.h | 59 ++++
> include/uapi/linux/dma-heap.h | 56 ++++
> tools/testing/selftests/dmabuf-heaps/Makefile | 11 +
> .../selftests/dmabuf-heaps/dmabuf-heap.c | 232 ++++++++++++++++
> 14 files changed, 1294 insertions(+)
> create mode 100644 drivers/dma-buf/dma-heap.c
> create mode 100644 drivers/dma-buf/heaps/Kconfig
> create mode 100644 drivers/dma-buf/heaps/Makefile
> create mode 100644 drivers/dma-buf/heaps/cma_heap.c
> create mode 100644 drivers/dma-buf/heaps/heap-helpers.c
> create mode 100644 drivers/dma-buf/heaps/heap-helpers.h
> create mode 100644 drivers/dma-buf/heaps/system_heap.c
> create mode 100644 include/linux/dma-heap.h
> create mode 100644 include/uapi/linux/dma-heap.h
> create mode 100644 tools/testing/selftests/dmabuf-heaps/Makefile
> create mode 100644 tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c
>
> --
> 2.17.1
>