From: Christoph Hellwig <hch@lst.de>
To: Tony Luck <tony.luck@intel.com>,
Fenghua Yu <fenghua.yu@intel.com>,
Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
iommu@lists.linux-foundation.org
Cc: linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
Robin Murphy <robin.murphy@arm.com>
Subject: [PATCH 11/12] dma-mapping: move dma_common_{mmap, get_sgtable} out of mapping.c
Date: Tue, 8 Sep 2020 18:47:57 +0200 [thread overview]
Message-ID: <20200908164758.3177341-12-hch@lst.de> (raw)
In-Reply-To: <20200908164758.3177341-1-hch@lst.de>
Add a new file that contains helpera for misc DMA ops, which is only
built when CONFIG_DMA_OPS is set.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
kernel/dma/Makefile | 1 +
kernel/dma/mapping.c | 47 +-----------------------------------
kernel/dma/ops_helpers.c | 51 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 53 insertions(+), 46 deletions(-)
create mode 100644 kernel/dma/ops_helpers.c
diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile
index 32c7c1942bbd6c..dc755ab68aabf9 100644
--- a/kernel/dma/Makefile
+++ b/kernel/dma/Makefile
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_HAS_DMA) += mapping.o direct.o
+obj-$(CONFIG_DMA_OPS) += ops_helpers.o
obj-$(CONFIG_DMA_OPS) += dummy.o
obj-$(CONFIG_DMA_CMA) += contiguous.o
obj-$(CONFIG_DMA_DECLARE_COHERENT) += coherent.o
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 0d129421e75fc8..848c95c27d79ff 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -8,7 +8,7 @@
#include <linux/memblock.h> /* for max_pfn */
#include <linux/acpi.h>
#include <linux/dma-direct.h>
-#include <linux/dma-noncoherent.h>
+#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/of_device.h>
@@ -295,22 +295,6 @@ void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
}
EXPORT_SYMBOL(dma_sync_sg_for_device);
-/*
- * Create scatter-list for the already allocated DMA buffer.
- */
-int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
- void *cpu_addr, dma_addr_t dma_addr, size_t size,
- unsigned long attrs)
-{
- struct page *page = virt_to_page(cpu_addr);
- int ret;
-
- ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
- if (!ret)
- sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
- return ret;
-}
-
/*
* The whole dma_get_sgtable() idea is fundamentally unsafe - it seems
* that the intention is to allow exporting memory allocated via the
@@ -358,35 +342,6 @@ pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs)
}
#endif /* CONFIG_MMU */
-/*
- * Create userspace mapping for the DMA-coherent memory.
- */
-int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
- void *cpu_addr, dma_addr_t dma_addr, size_t size,
- unsigned long attrs)
-{
-#ifdef CONFIG_MMU
- unsigned long user_count = vma_pages(vma);
- unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
- unsigned long off = vma->vm_pgoff;
- int ret = -ENXIO;
-
- vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
-
- if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
- return ret;
-
- if (off >= count || user_count > count - off)
- return -ENXIO;
-
- return remap_pfn_range(vma, vma->vm_start,
- page_to_pfn(virt_to_page(cpu_addr)) + vma->vm_pgoff,
- user_count << PAGE_SHIFT, vma->vm_page_prot);
-#else
- return -ENXIO;
-#endif /* CONFIG_MMU */
-}
-
/**
* dma_can_mmap - check if a given device supports dma_mmap_*
* @dev: device to check
diff --git a/kernel/dma/ops_helpers.c b/kernel/dma/ops_helpers.c
new file mode 100644
index 00000000000000..e443c69be4299f
--- /dev/null
+++ b/kernel/dma/ops_helpers.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helpers for DMA ops implementations. These generally rely on the fact that
+ * the allocated memory contains normal pages in the direct kernel mapping.
+ */
+#include <linux/dma-noncoherent.h>
+
+/*
+ * Create scatter-list for the already allocated DMA buffer.
+ */
+int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
+{
+ struct page *page = virt_to_page(cpu_addr);
+ int ret;
+
+ ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
+ if (!ret)
+ sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
+ return ret;
+}
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ */
+int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
+{
+#ifdef CONFIG_MMU
+ unsigned long user_count = vma_pages(vma);
+ unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ unsigned long off = vma->vm_pgoff;
+ int ret = -ENXIO;
+
+ vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
+
+ if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
+ return ret;
+
+ if (off >= count || user_count > count - off)
+ return -ENXIO;
+
+ return remap_pfn_range(vma, vma->vm_start,
+ page_to_pfn(virt_to_page(cpu_addr)) + vma->vm_pgoff,
+ user_count << PAGE_SHIFT, vma->vm_page_prot);
+#else
+ return -ENXIO;
+#endif /* CONFIG_MMU */
+}
--
2.28.0
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
next prev parent reply other threads:[~2020-09-08 16:48 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-08 16:47 dma-mapping cleanups Christoph Hellwig
2020-09-08 16:47 ` [PATCH 01/12] MIPS: make dma_sync_*_for_cpu a little less overzealous Christoph Hellwig
2020-09-08 16:47 ` [PATCH 02/12] MIPS/jazzdma: remove the unused vdma_remap function Christoph Hellwig
2020-09-08 16:47 ` [PATCH 03/12] MIPS/jazzdma: decouple from dma-direct Christoph Hellwig
2020-09-08 16:47 ` [PATCH 04/12] dma-mapping: fix DMA_OPS dependencies Christoph Hellwig
2020-09-08 18:04 ` Sergei Shtylyov
2020-09-11 7:10 ` Christoph Hellwig
2020-09-10 12:55 ` Robin Murphy
2020-09-11 7:09 ` Christoph Hellwig
2020-09-08 16:47 ` [PATCH 05/12] dma-mapping: add (back) arch_dma_mark_clean for ia64 Christoph Hellwig
2020-09-08 16:47 ` [PATCH 06/12] dma-direct: remove dma_direct_{alloc,free}_pages Christoph Hellwig
2020-09-10 12:57 ` Robin Murphy
2020-09-08 16:47 ` [PATCH 07/12] dma-direct: lift gfp_t manipulation out of__dma_direct_alloc_pages Christoph Hellwig
2020-09-10 13:02 ` Robin Murphy
2020-09-08 16:47 ` [PATCH 08/12] dma-direct: use phys_to_dma_direct in dma_direct_alloc Christoph Hellwig
2020-09-10 13:03 ` Robin Murphy
2020-09-08 16:47 ` [PATCH 09/12] dma-direct: remove __dma_to_phys Christoph Hellwig
2020-09-10 13:26 ` Robin Murphy
2020-09-11 7:14 ` Christoph Hellwig
2020-09-08 16:47 ` [PATCH 10/12] dma-direct: rename and cleanup __phys_to_dma Christoph Hellwig
2020-09-10 13:30 ` Robin Murphy
2020-09-08 16:47 ` Christoph Hellwig [this message]
2020-09-10 13:34 ` [PATCH 11/12] dma-mapping: move dma_common_{mmap, get_sgtable} out of mapping.c Robin Murphy
2020-09-11 7:15 ` [PATCH 11/12] dma-mapping: move dma_common_{mmap,get_sgtable} " Christoph Hellwig
2020-09-08 16:47 ` [PATCH 12/12] dma-mapping: move the dma_declare_coherent_memory documentation Christoph Hellwig
2020-09-10 13:51 ` Robin Murphy
2020-09-11 7:17 ` Christoph Hellwig
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200908164758.3177341-12-hch@lst.de \
--to=hch@lst.de \
--cc=fenghua.yu@intel.com \
--cc=iommu@lists.linux-foundation.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@vger.kernel.org \
--cc=robin.murphy@arm.com \
--cc=tony.luck@intel.com \
--cc=tsbogend@alpha.franken.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).