[PATCH 11/12] v4l: videobuf2: add CMA allocator (for testing)

From: Marek Szyprowski
Date: Thu Mar 31 2011 - 09:17:34 EST


Add support for the CMA contiguous memory allocator to videobuf2.

Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
CC: Pawel Osciak <pawel@xxxxxxxxxx>
CC: Michal Nazarewicz <mina86@xxxxxxxxxx>
---
drivers/media/video/Kconfig | 6 +
drivers/media/video/Makefile | 1 +
drivers/media/video/videobuf2-cma.c | 227 +++++++++++++++++++++++++++++++++++
include/media/videobuf2-cma.h | 40 ++++++
4 files changed, 274 insertions(+), 0 deletions(-)
create mode 100644 drivers/media/video/videobuf2-cma.c
create mode 100644 include/media/videobuf2-cma.h

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index 4498b94..d80c9d6 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -66,6 +66,12 @@ config VIDEOBUF2_DMA_SG
select VIDEOBUF2_CORE
select VIDEOBUF2_MEMOPS
tristate
+
+config VIDEOBUF2_CMA
+ depends on CMA
+ select VIDEOBUF2_CORE
+ select VIDEOBUF2_MEMOPS
+ tristate
#
# Multimedia Video device configuration
#
diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
index ace5d8b..86e98df 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -118,6 +118,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
+obj-$(CONFIG_VIDEOBUF2_CMA) += videobuf2-cma.o

obj-$(CONFIG_V4L2_MEM2MEM_DEV) += v4l2-mem2mem.o

diff --git a/drivers/media/video/videobuf2-cma.c b/drivers/media/video/videobuf2-cma.c
new file mode 100644
index 0000000..5dc7e89
--- /dev/null
+++ b/drivers/media/video/videobuf2-cma.c
@@ -0,0 +1,227 @@
+/*
+ * videobuf2-cma.c - CMA memory allocator for videobuf2
+ *
+ * Copyright (C) 2010-2011 Samsung Electronics
+ *
+ * Author: Pawel Osciak <p.osciak@xxxxxxxxxxx>
+ * Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/cma.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/file.h>
+
+#include <media/videobuf2-core.h>
+#include <media/videobuf2-memops.h>
+
+#include <asm/io.h>
+
+struct vb2_cma_conf {
+ struct device *dev;
+ const char *type;
+ unsigned long alignment;
+};
+
+struct vb2_cma_buf {
+ struct vb2_cma_conf *conf;
+ struct cm *cm;
+ dma_addr_t paddr;
+ unsigned long size;
+ struct vm_area_struct *vma;
+ atomic_t refcount;
+ struct vb2_vmarea_handler handler;
+};
+
+static void vb2_cma_put(void *buf_priv);
+
+static void *vb2_cma_alloc(void *alloc_ctx, unsigned long size)
+{
+ struct vb2_cma_conf *conf = alloc_ctx;
+ struct vb2_cma_buf *buf;
+
+ buf = kzalloc(sizeof *buf, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ buf->cm = cma_alloc(conf->dev, conf->type, size, conf->alignment);
+ if (IS_ERR(buf->cm)) {
+ printk(KERN_ERR "cma_alloc of size %ld failed\n", size);
+ kfree(buf);
+ return ERR_PTR(-ENOMEM);
+ }
+ buf->paddr = cm_pin(buf->cm);
+ buf->conf = conf;
+ buf->size = size;
+
+ buf->handler.refcount = &buf->refcount;
+ buf->handler.put = vb2_cma_put;
+ buf->handler.arg = buf;
+
+ atomic_inc(&buf->refcount);
+
+ return buf;
+}
+
+static void vb2_cma_put(void *buf_priv)
+{
+ struct vb2_cma_buf *buf = buf_priv;
+
+ if (atomic_dec_and_test(&buf->refcount)) {
+ cm_unpin(buf->cm);
+ cma_free(buf->cm);
+ kfree(buf);
+ }
+}
+
+static void *vb2_cma_cookie(void *buf_priv)
+{
+ struct vb2_cma_buf *buf = buf_priv;
+
+ return (void *)buf->paddr;
+}
+
+static unsigned int vb2_cma_num_users(void *buf_priv)
+{
+ struct vb2_cma_buf *buf = buf_priv;
+
+ return atomic_read(&buf->refcount);
+}
+
+static int vb2_cma_mmap(void *buf_priv, struct vm_area_struct *vma)
+{
+ struct vb2_cma_buf *buf = buf_priv;
+
+ if (!buf) {
+ printk(KERN_ERR "No buffer to map\n");
+ return -EINVAL;
+ }
+
+ return vb2_mmap_pfn_range(vma, buf->paddr, buf->size,
+ &vb2_common_vm_ops, &buf->handler);
+}
+
+static void *vb2_cma_get_userptr(void *alloc_ctx, unsigned long vaddr,
+ unsigned long size, int write)
+{
+ struct vb2_cma_buf *buf;
+ struct vm_area_struct *vma;
+ dma_addr_t paddr = 0;
+ int ret;
+
+ buf = kzalloc(sizeof *buf, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ ret = vb2_get_contig_userptr(vaddr, size, &vma, &paddr);
+ if (ret) {
+ printk(KERN_ERR "Failed acquiring VMA for vaddr 0x%08lx\n",
+ vaddr);
+ kfree(buf);
+ return ERR_PTR(ret);
+ }
+
+ buf->size = size;
+ buf->paddr = paddr;
+ buf->vma = vma;
+
+ return buf;
+}
+
+static void vb2_cma_put_userptr(void *mem_priv)
+{
+ struct vb2_cma_buf *buf = mem_priv;
+
+ if (!buf)
+ return;
+
+ vb2_put_vma(buf->vma);
+ kfree(buf);
+}
+
+static void *vb2_cma_vaddr(void *mem_priv)
+{
+ struct vb2_cma_buf *buf = mem_priv;
+ if (!buf)
+ return 0;
+
+ return phys_to_virt(buf->paddr);
+}
+
+const struct vb2_mem_ops vb2_cma_memops = {
+ .alloc = vb2_cma_alloc,
+ .put = vb2_cma_put,
+ .cookie = vb2_cma_cookie,
+ .mmap = vb2_cma_mmap,
+ .get_userptr = vb2_cma_get_userptr,
+ .put_userptr = vb2_cma_put_userptr,
+ .num_users = vb2_cma_num_users,
+ .vaddr = vb2_cma_vaddr,
+};
+EXPORT_SYMBOL_GPL(vb2_cma_memops);
+
+void *vb2_cma_init(struct device *dev, const char *type,
+ unsigned long alignment)
+{
+ struct vb2_cma_conf *conf;
+
+ conf = kzalloc(sizeof *conf, GFP_KERNEL);
+ if (!conf)
+ return ERR_PTR(-ENOMEM);
+
+ conf->dev = dev;
+ conf->type = type;
+ conf->alignment = alignment;
+
+ return conf;
+}
+EXPORT_SYMBOL_GPL(vb2_cma_init);
+
+void vb2_cma_cleanup(void *conf)
+{
+ kfree(conf);
+}
+EXPORT_SYMBOL_GPL(vb2_cma_cleanup);
+
+void **vb2_cma_init_multi(struct device *dev,
+ unsigned int num_planes,
+ const char *types[],
+ unsigned long alignments[])
+{
+ struct vb2_cma_conf *cma_conf;
+ void **alloc_ctxes;
+ unsigned int i;
+
+ alloc_ctxes = kzalloc((sizeof *alloc_ctxes + sizeof *cma_conf)
+ * num_planes, GFP_KERNEL);
+ if (!alloc_ctxes)
+ return ERR_PTR(-ENOMEM);
+
+ cma_conf = (void *)(alloc_ctxes + num_planes);
+
+ for (i = 0; i < num_planes; ++i, ++cma_conf) {
+ alloc_ctxes[i] = cma_conf;
+ cma_conf->dev = dev;
+ cma_conf->type = types[i];
+ cma_conf->alignment = alignments[i];
+ }
+
+ return alloc_ctxes;
+}
+EXPORT_SYMBOL_GPL(vb2_cma_init_multi);
+
+void vb2_cma_cleanup_multi(void **alloc_ctxes)
+{
+ kfree(alloc_ctxes);
+}
+EXPORT_SYMBOL_GPL(vb2_cma_cleanup_multi);
+
+MODULE_DESCRIPTION("CMA allocator handling routines for videobuf2");
+MODULE_AUTHOR("Pawel Osciak");
+MODULE_LICENSE("GPL");
diff --git a/include/media/videobuf2-cma.h b/include/media/videobuf2-cma.h
new file mode 100644
index 0000000..ba8dad5
--- /dev/null
+++ b/include/media/videobuf2-cma.h
@@ -0,0 +1,40 @@
+/*
+ * videobuf2-cma.h - CMA memory allocator for videobuf2
+ *
+ * Copyright (C) 2010-2011 Samsung Electronics
+ *
+ * Author: Pawel Osciak <p.osciak@xxxxxxxxxxx>
+ * Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+
+#ifndef _MEDIA_VIDEOBUF2_CMA_H
+#define _MEDIA_VIDEOBUF2_CMA_H
+
+#include <media/videobuf2-core.h>
+
+static inline unsigned long vb2_cma_plane_paddr(struct vb2_buffer *vb,
+ unsigned int plane_no)
+{
+ return (unsigned long)vb2_plane_cookie(vb, plane_no);
+}
+
+struct vb2_alloc_ctx *vb2_cma_init(struct device *dev, const char *type,
+ unsigned long alignment);
+void vb2_cma_cleanup(struct vb2_alloc_ctx *alloc_ctx);
+
+struct vb2_alloc_ctx **vb2_cma_init_multi(struct device *dev,
+ unsigned int num_planes, const char *types[],
+ unsigned long alignments[]);
+void vb2_cma_cleanup_multi(struct vb2_alloc_ctx **alloc_ctxes);
+
+struct vb2_alloc_ctx *vb2_cma_init(struct device *dev, const char *type,
+ unsigned long alignment);
+void vb2_cma_cleanup(struct vb2_alloc_ctx *alloc_ctx);
+
+extern const struct vb2_mem_ops vb2_cma_memops;
+
+#endif
--
1.7.1.569.g6f426
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