diff mbox series

[v7,2/5] dma-buf: heaps: Move heap-helper logic into the cma_heap implementation

Message ID 20201121235002.69945-3-john.stultz@linaro.org
State Superseded
Headers show
Series dma-buf: Code rework and performance improvements for system heap | expand

Commit Message

John Stultz Nov. 21, 2020, 11:49 p.m. UTC
Since the heap-helpers logic ended up not being as generic as
hoped, move the heap-helpers dma_buf_ops implementations into
the cma_heap directly.

This will allow us to remove the heap_helpers code in a following
patch.

Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: Daniel Mentz <danielmentz@google.com>
Cc: Chris Goldsworthy <cgoldswo@codeaurora.org>
Cc: Ørjan Eide <orjan.eide@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Ezequiel Garcia <ezequiel@collabora.com>
Cc: Simon Ser <contact@emersion.fr>
Cc: James Jones <jajones@nvidia.com>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Brian Starkey <brian.starkey@arm.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
v2:
* Fix unused return value and locking issue Reported-by:
    kernel test robot <lkp@intel.com>
    Julia Lawall <julia.lawall@inria.fr>
* Make cma_heap_buf_ops static suggested by
    kernel test robot <lkp@intel.com>
* Fix uninitialized return in cma Reported-by:
    kernel test robot <lkp@intel.com>
* Minor cleanups
v3:
* Use the new sgtable mapping functions, as Suggested-by:
     Daniel Mentz <danielmentz@google.com>
v4:
* Spelling fix suggested by BrianS
v6:
* Fixups against drm-misc-next
v7:
* Redo the incorrect dma-buf-map adaptation in the last revision
---
 drivers/dma-buf/heaps/cma_heap.c | 319 ++++++++++++++++++++++++++-----
 1 file changed, 270 insertions(+), 49 deletions(-)

Comments

Guenter Roeck Dec. 15, 2020, 11:53 p.m. UTC | #1
On Sat, Nov 21, 2020 at 11:49:59PM +0000, John Stultz wrote:
> Since the heap-helpers logic ended up not being as generic as
> hoped, move the heap-helpers dma_buf_ops implementations into
> the cma_heap directly.
> 
> This will allow us to remove the heap_helpers code in a following
> patch.
> 

mips:allmodconfig:

drivers/dma-buf/heaps/cma_heap.c: In function 'cma_heap_do_vmap':
drivers/dma-buf/heaps/cma_heap.c:195:10: error: implicit declaration of function 'vmap'

Bisect log attached.

Guenter

---
# bad: [9317f948b0b188b8d2fded75957e6d42c460df1b] Add linux-next specific files for 20201215
# good: [2c85ebc57b3e1817b6ce1a6b703928e113a90442] Linux 5.10
git bisect start 'HEAD' 'v5.10'
# good: [8357e709304f1791b390c34f63cd00cb434a9ea9] Merge remote-tracking branch 'pm/linux-next'
git bisect good 8357e709304f1791b390c34f63cd00cb434a9ea9
# bad: [e43c4376b37c58a054444fe2f512aebfc7362306] Merge remote-tracking branch 'tomoyo/master'
git bisect bad e43c4376b37c58a054444fe2f512aebfc7362306
# good: [6f2d5cf9756dab190e79edd4ec098c81dca6743c] net: stmmac: simplify the return dwmac5_rxp_disable()
git bisect good 6f2d5cf9756dab190e79edd4ec098c81dca6743c
# bad: [fef5fe5f601c5826083b81837800b8b99570bfb0] Merge remote-tracking branch 'drm-misc/for-linux-next'
git bisect bad fef5fe5f601c5826083b81837800b8b99570bfb0
# good: [5bb0c4b5eb61d939fed0b27d11fb91fb85769c9a] ice, xsk: Move Rx allocation out of while-loop
git bisect good 5bb0c4b5eb61d939fed0b27d11fb91fb85769c9a
# good: [b54139eb968d982bfd5f451a8d143f3f6cdd82cf] Merge remote-tracking branch 'mtd/mtd/next'
git bisect good b54139eb968d982bfd5f451a8d143f3f6cdd82cf
# good: [f42a3d780d2ff7a122b089460f4bfbe402b4e27e] Merge remote-tracking branch 'amdgpu/drm-next'
git bisect good f42a3d780d2ff7a122b089460f4bfbe402b4e27e
# good: [3a9ec563a4ff770ae647f6ee539810f1866866c9] drm/i915/icl: Fix initing the DSI DSC power refcount during HW readout
git bisect good 3a9ec563a4ff770ae647f6ee539810f1866866c9
# bad: [2c3a1e49696fd05b52ec5eeb7c006ac32724c915] video: fbdev: lxfb_ops: Fix fall-through warnings for Clang
git bisect bad 2c3a1e49696fd05b52ec5eeb7c006ac32724c915
# good: [2ac5ef3b23629e9740000948c48f4141bacb5abb] drm: document drm_mode_get_connector
git bisect good 2ac5ef3b23629e9740000948c48f4141bacb5abb
# good: [2b6cb81b95d1e8abfb6d32cf194a5bd2992c315c] drm/meson: dw-hdmi: Enable the iahb clock early enough
git bisect good 2b6cb81b95d1e8abfb6d32cf194a5bd2992c315c
# bad: [4c68e499bb9d6d9ec3e18fcb2f68641abb22464a] dma-buf: heaps: Skip sync if not mapped
git bisect bad 4c68e499bb9d6d9ec3e18fcb2f68641abb22464a
# bad: [a5d2d29e24be8967ef78a1b1fb2292413e3b3df9] dma-buf: heaps: Move heap-helper logic into the cma_heap implementation
git bisect bad a5d2d29e24be8967ef78a1b1fb2292413e3b3df9
# good: [3812957587923ca325308ed9c4a5be5ca935e903] dma-buf: system_heap: Rework system heap to use sgtables instead of pagelists
git bisect good 3812957587923ca325308ed9c4a5be5ca935e903
# first bad commit: [a5d2d29e24be8967ef78a1b1fb2292413e3b3df9] dma-buf: heaps: Move heap-helper logic into the cma_heap implementation
Sumit Semwal Dec. 16, 2020, 5:57 p.m. UTC | #2
Hi John,


On Wed, 16 Dec 2020 at 06:19, John Stultz <john.stultz@linaro.org> wrote:
>
> We need to include <linux/vmalloc.h> in order for MIPS to find
> vmap(), as it doesn't otherwise get included there.
>
> Without this patch, one can hit the following build error:
>   drivers/dma-buf/heaps/cma_heap.c: In function 'cma_heap_do_vmap':
>   drivers/dma-buf/heaps/cma_heap.c:195:10: error: implicit declaration of function 'vmap'

Thanks for the patch; I've merged it to drm-misc-next-fixes.

>
> Cc: Sumit Semwal <sumit.semwal@linaro.org>
> Cc: Liam Mark <lmark@codeaurora.org>
> Cc: Laura Abbott <labbott@kernel.org>
> Cc: Brian Starkey <Brian.Starkey@arm.com>
> Cc: Hridya Valsaraju <hridya@google.com>
> Cc: Suren Baghdasaryan <surenb@google.com>
> Cc: Sandeep Patil <sspatil@google.com>
> Cc: Daniel Mentz <danielmentz@google.com>
> Cc: Chris Goldsworthy <cgoldswo@codeaurora.org>
> Cc: Ørjan Eide <orjan.eide@arm.com>
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: Ezequiel Garcia <ezequiel@collabora.com>
> Cc: Simon Ser <contact@emersion.fr>
> Cc: James Jones <jajones@nvidia.com>
> Cc: linux-media@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Fixes: a5d2d29e24be ("dma-buf: heaps: Move heap-helper logic into the cma_heap implementation")
> Reported-by: Guenter Roeck <linux@roeck-us.net>
> Signed-off-by: John Stultz <john.stultz@linaro.org>
> ---
>  drivers/dma-buf/heaps/cma_heap.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
> index 5e7c3436310c..3c4e34301172 100644
> --- a/drivers/dma-buf/heaps/cma_heap.c
> +++ b/drivers/dma-buf/heaps/cma_heap.c
> @@ -20,6 +20,7 @@
>  #include <linux/module.h>
>  #include <linux/scatterlist.h>
>  #include <linux/slab.h>
> +#include <linux/vmalloc.h>
>
>
>  struct cma_heap {
> --
> 2.17.1
>
Best,
Sumit.
diff mbox series

Patch

diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
index e55384dc115b..05aaa4f29397 100644
--- a/drivers/dma-buf/heaps/cma_heap.c
+++ b/drivers/dma-buf/heaps/cma_heap.c
@@ -2,76 +2,295 @@ 
 /*
  * DMABUF CMA heap exporter
  *
- * Copyright (C) 2012, 2019 Linaro Ltd.
+ * Copyright (C) 2012, 2019, 2020 Linaro Ltd.
  * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson.
+ *
+ * Also utilizing parts of Andrew Davis' SRAM heap:
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
+ *	Andrew F. Davis <afd@ti.com>
  */
-
 #include <linux/cma.h>
-#include <linux/device.h>
 #include <linux/dma-buf.h>
 #include <linux/dma-heap.h>
 #include <linux/dma-map-ops.h>
 #include <linux/err.h>
-#include <linux/errno.h>
 #include <linux/highmem.h>
+#include <linux/io.h>
+#include <linux/mm.h>
 #include <linux/module.h>
-#include <linux/slab.h>
 #include <linux/scatterlist.h>
-#include <linux/sched/signal.h>
+#include <linux/slab.h>
 
-#include "heap-helpers.h"
 
 struct cma_heap {
 	struct dma_heap *heap;
 	struct cma *cma;
 };
 
-static void cma_heap_free(struct heap_helper_buffer *buffer)
+struct cma_heap_buffer {
+	struct cma_heap *heap;
+	struct list_head attachments;
+	struct mutex lock;
+	unsigned long len;
+	struct page *cma_pages;
+	struct page **pages;
+	pgoff_t pagecount;
+	int vmap_cnt;
+	void *vaddr;
+};
+
+struct dma_heap_attachment {
+	struct device *dev;
+	struct sg_table table;
+	struct list_head list;
+};
+
+static int cma_heap_attach(struct dma_buf *dmabuf,
+			   struct dma_buf_attachment *attachment)
 {
-	struct cma_heap *cma_heap = dma_heap_get_drvdata(buffer->heap);
-	unsigned long nr_pages = buffer->pagecount;
-	struct page *cma_pages = buffer->priv_virt;
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+	struct dma_heap_attachment *a;
+	int ret;
 
-	/* free page list */
-	kfree(buffer->pages);
-	/* release memory */
-	cma_release(cma_heap->cma, cma_pages, nr_pages);
+	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 cma_heap_detach(struct dma_buf *dmabuf,
+			    struct dma_buf_attachment *attachment)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+	struct dma_heap_attachment *a = attachment->priv;
+
+	mutex_lock(&buffer->lock);
+	list_del(&a->list);
+	mutex_unlock(&buffer->lock);
+
+	sg_free_table(&a->table);
+	kfree(a);
+}
+
+static struct sg_table *cma_heap_map_dma_buf(struct dma_buf_attachment *attachment,
+					     enum dma_data_direction direction)
+{
+	struct dma_heap_attachment *a = attachment->priv;
+	struct sg_table *table = &a->table;
+	int ret;
+
+	ret = dma_map_sgtable(attachment->dev, table, direction, 0);
+	if (ret)
+		return ERR_PTR(-ENOMEM);
+	return table;
+}
+
+static void cma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
+				   struct sg_table *table,
+				   enum dma_data_direction direction)
+{
+	dma_unmap_sgtable(attachment->dev, table, direction, 0);
+}
+
+static int cma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
+					     enum dma_data_direction direction)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+	struct dma_heap_attachment *a;
+
+	if (buffer->vmap_cnt)
+		invalidate_kernel_vmap_range(buffer->vaddr, buffer->len);
+
+	mutex_lock(&buffer->lock);
+	list_for_each_entry(a, &buffer->attachments, list) {
+		dma_sync_sgtable_for_cpu(a->dev, &a->table, direction);
+	}
+	mutex_unlock(&buffer->lock);
+
+	return 0;
+}
+
+static int cma_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
+					   enum dma_data_direction direction)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+	struct dma_heap_attachment *a;
+
+	if (buffer->vmap_cnt)
+		flush_kernel_vmap_range(buffer->vaddr, buffer->len);
+
+	mutex_lock(&buffer->lock);
+	list_for_each_entry(a, &buffer->attachments, list) {
+		dma_sync_sgtable_for_device(a->dev, &a->table, direction);
+	}
+	mutex_unlock(&buffer->lock);
+
+	return 0;
+}
+
+static vm_fault_t cma_heap_vm_fault(struct vm_fault *vmf)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct cma_heap_buffer *buffer = vma->vm_private_data;
+
+	if (vmf->pgoff > buffer->pagecount)
+		return VM_FAULT_SIGBUS;
+
+	vmf->page = buffer->pages[vmf->pgoff];
+	get_page(vmf->page);
+
+	return 0;
+}
+
+static const struct vm_operations_struct dma_heap_vm_ops = {
+	.fault = cma_heap_vm_fault,
+};
+
+static int cma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+
+	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 *cma_heap_do_vmap(struct cma_heap_buffer *buffer)
+{
+	void *vaddr;
+
+	vaddr = vmap(buffer->pages, buffer->pagecount, VM_MAP, PAGE_KERNEL);
+	if (!vaddr)
+		return ERR_PTR(-ENOMEM);
+
+	return vaddr;
+}
+
+static int cma_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+	void *vaddr;
+	int ret = 0;
+
+	mutex_lock(&buffer->lock);
+	if (buffer->vmap_cnt) {
+		buffer->vmap_cnt++;
+		dma_buf_map_set_vaddr(map, buffer->vaddr);
+		goto out;
+	}
+
+	vaddr = cma_heap_do_vmap(buffer);
+	if (IS_ERR(vaddr)) {
+		ret = PTR_ERR(vaddr);
+		goto out;
+	}
+	buffer->vaddr = vaddr;
+	buffer->vmap_cnt++;
+	dma_buf_map_set_vaddr(map, buffer->vaddr);
+out:
+	mutex_unlock(&buffer->lock);
+
+	return ret;
+}
+
+static void cma_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+
+	mutex_lock(&buffer->lock);
+	if (!--buffer->vmap_cnt) {
+		vunmap(buffer->vaddr);
+		buffer->vaddr = NULL;
+	}
+	mutex_unlock(&buffer->lock);
+	dma_buf_map_clear(map);
+}
+
+static void cma_heap_dma_buf_release(struct dma_buf *dmabuf)
+{
+	struct cma_heap_buffer *buffer = dmabuf->priv;
+	struct cma_heap *cma_heap = buffer->heap;
+
+	if (buffer->vmap_cnt > 0) {
+		WARN(1, "%s: buffer still mapped in the kernel\n", __func__);
+		vunmap(buffer->vaddr);
+		buffer->vaddr = NULL;
+	}
+
+	cma_release(cma_heap->cma, buffer->cma_pages, buffer->pagecount);
 	kfree(buffer);
 }
 
-/* dmabuf heap CMA operations functions */
+static const struct dma_buf_ops cma_heap_buf_ops = {
+	.attach = cma_heap_attach,
+	.detach = cma_heap_detach,
+	.map_dma_buf = cma_heap_map_dma_buf,
+	.unmap_dma_buf = cma_heap_unmap_dma_buf,
+	.begin_cpu_access = cma_heap_dma_buf_begin_cpu_access,
+	.end_cpu_access = cma_heap_dma_buf_end_cpu_access,
+	.mmap = cma_heap_mmap,
+	.vmap = cma_heap_vmap,
+	.vunmap = cma_heap_vunmap,
+	.release = cma_heap_dma_buf_release,
+};
+
 static int cma_heap_allocate(struct dma_heap *heap,
-			     unsigned long len,
-			     unsigned long fd_flags,
-			     unsigned long heap_flags)
+				  unsigned long len,
+				  unsigned long fd_flags,
+				  unsigned long heap_flags)
 {
 	struct cma_heap *cma_heap = dma_heap_get_drvdata(heap);
-	struct heap_helper_buffer *helper_buffer;
-	struct page *cma_pages;
+	struct cma_heap_buffer *buffer;
+	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 	size_t size = PAGE_ALIGN(len);
-	unsigned long nr_pages = size >> PAGE_SHIFT;
+	pgoff_t pagecount = size >> PAGE_SHIFT;
 	unsigned long align = get_order(size);
+	struct page *cma_pages;
 	struct dma_buf *dmabuf;
 	int ret = -ENOMEM;
 	pgoff_t pg;
 
-	if (align > CONFIG_CMA_ALIGNMENT)
-		align = CONFIG_CMA_ALIGNMENT;
-
-	helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL);
-	if (!helper_buffer)
+	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+	if (!buffer)
 		return -ENOMEM;
 
-	init_heap_helper_buffer(helper_buffer, cma_heap_free);
-	helper_buffer->heap = heap;
-	helper_buffer->size = len;
+	INIT_LIST_HEAD(&buffer->attachments);
+	mutex_init(&buffer->lock);
+	buffer->len = size;
+
+	if (align > CONFIG_CMA_ALIGNMENT)
+		align = CONFIG_CMA_ALIGNMENT;
 
-	cma_pages = cma_alloc(cma_heap->cma, nr_pages, align, false);
+	cma_pages = cma_alloc(cma_heap->cma, pagecount, align, false);
 	if (!cma_pages)
-		goto free_buf;
+		goto free_buffer;
 
+	/* Clear the cma pages */
 	if (PageHighMem(cma_pages)) {
-		unsigned long nr_clear_pages = nr_pages;
+		unsigned long nr_clear_pages = pagecount;
 		struct page *page = cma_pages;
 
 		while (nr_clear_pages > 0) {
@@ -85,7 +304,6 @@  static int cma_heap_allocate(struct dma_heap *heap,
 			 */
 			if (fatal_signal_pending(current))
 				goto free_cma;
-
 			page++;
 			nr_clear_pages--;
 		}
@@ -93,28 +311,30 @@  static int cma_heap_allocate(struct dma_heap *heap,
 		memset(page_address(cma_pages), 0, size);
 	}
 
-	helper_buffer->pagecount = nr_pages;
-	helper_buffer->pages = kmalloc_array(helper_buffer->pagecount,
-					     sizeof(*helper_buffer->pages),
-					     GFP_KERNEL);
-	if (!helper_buffer->pages) {
+	buffer->pages = kmalloc_array(pagecount, sizeof(*buffer->pages), GFP_KERNEL);
+	if (!buffer->pages) {
 		ret = -ENOMEM;
 		goto free_cma;
 	}
 
-	for (pg = 0; pg < helper_buffer->pagecount; pg++)
-		helper_buffer->pages[pg] = &cma_pages[pg];
+	for (pg = 0; pg < pagecount; pg++)
+		buffer->pages[pg] = &cma_pages[pg];
+
+	buffer->cma_pages = cma_pages;
+	buffer->heap = cma_heap;
+	buffer->pagecount = pagecount;
 
 	/* create the dmabuf */
-	dmabuf = heap_helper_export_dmabuf(helper_buffer, fd_flags);
+	exp_info.ops = &cma_heap_buf_ops;
+	exp_info.size = buffer->len;
+	exp_info.flags = fd_flags;
+	exp_info.priv = buffer;
+	dmabuf = dma_buf_export(&exp_info);
 	if (IS_ERR(dmabuf)) {
 		ret = PTR_ERR(dmabuf);
 		goto free_pages;
 	}
 
-	helper_buffer->dmabuf = dmabuf;
-	helper_buffer->priv_virt = cma_pages;
-
 	ret = dma_buf_fd(dmabuf, fd_flags);
 	if (ret < 0) {
 		dma_buf_put(dmabuf);
@@ -125,11 +345,12 @@  static int cma_heap_allocate(struct dma_heap *heap,
 	return ret;
 
 free_pages:
-	kfree(helper_buffer->pages);
+	kfree(buffer->pages);
 free_cma:
-	cma_release(cma_heap->cma, cma_pages, nr_pages);
-free_buf:
-	kfree(helper_buffer);
+	cma_release(cma_heap->cma, cma_pages, pagecount);
+free_buffer:
+	kfree(buffer);
+
 	return ret;
 }