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authorMaarten Lankhorst <maarten.lankhorst@canonical.com>2014-07-01 12:57:08 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-07-08 10:51:06 -0700
commit35fac7e305dc5e0bd1e52f2505944674337de57c (patch)
treec29dd4051f7d557bc812cf459108412c7174974a /drivers/dma-buf
parent650f81d40957cf5bc07de1210591339c6242a361 (diff)
downloadlinux-linaro-stable-35fac7e305dc5e0bd1e52f2505944674337de57c.tar.gz
dma-buf: move to drivers/dma-buf
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/dma-buf')
-rw-r--r--drivers/dma-buf/Makefile1
-rw-r--r--drivers/dma-buf/dma-buf.c743
-rw-r--r--drivers/dma-buf/reservation.c39
3 files changed, 783 insertions, 0 deletions
diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile
new file mode 100644
index 000000000000..4a4f4c9bacd0
--- /dev/null
+++ b/drivers/dma-buf/Makefile
@@ -0,0 +1 @@
+obj-y := dma-buf.o reservation.o
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
new file mode 100644
index 000000000000..840c7fa80983
--- /dev/null
+++ b/drivers/dma-buf/dma-buf.c
@@ -0,0 +1,743 @@
+/*
+ * Framework for buffer objects that can be shared across devices/subsystems.
+ *
+ * Copyright(C) 2011 Linaro Limited. All rights reserved.
+ * Author: Sumit Semwal <sumit.semwal@ti.com>
+ *
+ * Many thanks to linaro-mm-sig list, and specially
+ * Arnd Bergmann <arnd@arndb.de>, Rob Clark <rob@ti.com> and
+ * Daniel Vetter <daniel@ffwll.ch> for their support in creation and
+ * refining of this idea.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/dma-buf.h>
+#include <linux/anon_inodes.h>
+#include <linux/export.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+static inline int is_dma_buf_file(struct file *);
+
+struct dma_buf_list {
+ struct list_head head;
+ struct mutex lock;
+};
+
+static struct dma_buf_list db_list;
+
+static int dma_buf_release(struct inode *inode, struct file *file)
+{
+ struct dma_buf *dmabuf;
+
+ if (!is_dma_buf_file(file))
+ return -EINVAL;
+
+ dmabuf = file->private_data;
+
+ BUG_ON(dmabuf->vmapping_counter);
+
+ dmabuf->ops->release(dmabuf);
+
+ mutex_lock(&db_list.lock);
+ list_del(&dmabuf->list_node);
+ mutex_unlock(&db_list.lock);
+
+ kfree(dmabuf);
+ return 0;
+}
+
+static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
+{
+ struct dma_buf *dmabuf;
+
+ if (!is_dma_buf_file(file))
+ return -EINVAL;
+
+ dmabuf = file->private_data;
+
+ /* check for overflowing the buffer's size */
+ if (vma->vm_pgoff + ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) >
+ dmabuf->size >> PAGE_SHIFT)
+ return -EINVAL;
+
+ return dmabuf->ops->mmap(dmabuf, vma);
+}
+
+static loff_t dma_buf_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct dma_buf *dmabuf;
+ loff_t base;
+
+ if (!is_dma_buf_file(file))
+ return -EBADF;
+
+ dmabuf = file->private_data;
+
+ /* only support discovering the end of the buffer,
+ but also allow SEEK_SET to maintain the idiomatic
+ SEEK_END(0), SEEK_CUR(0) pattern */
+ if (whence == SEEK_END)
+ base = dmabuf->size;
+ else if (whence == SEEK_SET)
+ base = 0;
+ else
+ return -EINVAL;
+
+ if (offset != 0)
+ return -EINVAL;
+
+ return base + offset;
+}
+
+static const struct file_operations dma_buf_fops = {
+ .release = dma_buf_release,
+ .mmap = dma_buf_mmap_internal,
+ .llseek = dma_buf_llseek,
+};
+
+/*
+ * is_dma_buf_file - Check if struct file* is associated with dma_buf
+ */
+static inline int is_dma_buf_file(struct file *file)
+{
+ return file->f_op == &dma_buf_fops;
+}
+
+/**
+ * dma_buf_export_named - Creates a new dma_buf, and associates an anon file
+ * with this buffer, so it can be exported.
+ * Also connect the allocator specific data and ops to the buffer.
+ * Additionally, provide a name string for exporter; useful in debugging.
+ *
+ * @priv: [in] Attach private data of allocator to this buffer
+ * @ops: [in] Attach allocator-defined dma buf ops to the new buffer.
+ * @size: [in] Size of the buffer
+ * @flags: [in] mode flags for the file.
+ * @exp_name: [in] name of the exporting module - useful for debugging.
+ *
+ * Returns, on success, a newly created dma_buf object, which wraps the
+ * supplied private data and operations for dma_buf_ops. On either missing
+ * ops, or error in allocating struct dma_buf, will return negative error.
+ *
+ */
+struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
+ size_t size, int flags, const char *exp_name)
+{
+ struct dma_buf *dmabuf;
+ struct file *file;
+
+ if (WARN_ON(!priv || !ops
+ || !ops->map_dma_buf
+ || !ops->unmap_dma_buf
+ || !ops->release
+ || !ops->kmap_atomic
+ || !ops->kmap
+ || !ops->mmap)) {
+ return ERR_PTR(-EINVAL);
+ }
+
+ dmabuf = kzalloc(sizeof(struct dma_buf), GFP_KERNEL);
+ if (dmabuf == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ dmabuf->priv = priv;
+ dmabuf->ops = ops;
+ dmabuf->size = size;
+ dmabuf->exp_name = exp_name;
+
+ file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf, flags);
+ if (IS_ERR(file)) {
+ kfree(dmabuf);
+ return ERR_CAST(file);
+ }
+
+ file->f_mode |= FMODE_LSEEK;
+ dmabuf->file = file;
+
+ mutex_init(&dmabuf->lock);
+ INIT_LIST_HEAD(&dmabuf->attachments);
+
+ mutex_lock(&db_list.lock);
+ list_add(&dmabuf->list_node, &db_list.head);
+ mutex_unlock(&db_list.lock);
+
+ return dmabuf;
+}
+EXPORT_SYMBOL_GPL(dma_buf_export_named);
+
+
+/**
+ * dma_buf_fd - returns a file descriptor for the given dma_buf
+ * @dmabuf: [in] pointer to dma_buf for which fd is required.
+ * @flags: [in] flags to give to fd
+ *
+ * On success, returns an associated 'fd'. Else, returns error.
+ */
+int dma_buf_fd(struct dma_buf *dmabuf, int flags)
+{
+ int fd;
+
+ if (!dmabuf || !dmabuf->file)
+ return -EINVAL;
+
+ fd = get_unused_fd_flags(flags);
+ if (fd < 0)
+ return fd;
+
+ fd_install(fd, dmabuf->file);
+
+ return fd;
+}
+EXPORT_SYMBOL_GPL(dma_buf_fd);
+
+/**
+ * dma_buf_get - returns the dma_buf structure related to an fd
+ * @fd: [in] fd associated with the dma_buf to be returned
+ *
+ * On success, returns the dma_buf structure associated with an fd; uses
+ * file's refcounting done by fget to increase refcount. returns ERR_PTR
+ * otherwise.
+ */
+struct dma_buf *dma_buf_get(int fd)
+{
+ struct file *file;
+
+ file = fget(fd);
+
+ if (!file)
+ return ERR_PTR(-EBADF);
+
+ if (!is_dma_buf_file(file)) {
+ fput(file);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return file->private_data;
+}
+EXPORT_SYMBOL_GPL(dma_buf_get);
+
+/**
+ * dma_buf_put - decreases refcount of the buffer
+ * @dmabuf: [in] buffer to reduce refcount of
+ *
+ * Uses file's refcounting done implicitly by fput()
+ */
+void dma_buf_put(struct dma_buf *dmabuf)
+{
+ if (WARN_ON(!dmabuf || !dmabuf->file))
+ return;
+
+ fput(dmabuf->file);
+}
+EXPORT_SYMBOL_GPL(dma_buf_put);
+
+/**
+ * dma_buf_attach - Add the device to dma_buf's attachments list; optionally,
+ * calls attach() of dma_buf_ops to allow device-specific attach functionality
+ * @dmabuf: [in] buffer to attach device to.
+ * @dev: [in] device to be attached.
+ *
+ * Returns struct dma_buf_attachment * for this attachment; returns ERR_PTR on
+ * error.
+ */
+struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf,
+ struct device *dev)
+{
+ struct dma_buf_attachment *attach;
+ int ret;
+
+ if (WARN_ON(!dmabuf || !dev))
+ return ERR_PTR(-EINVAL);
+
+ attach = kzalloc(sizeof(struct dma_buf_attachment), GFP_KERNEL);
+ if (attach == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ attach->dev = dev;
+ attach->dmabuf = dmabuf;
+
+ mutex_lock(&dmabuf->lock);
+
+ if (dmabuf->ops->attach) {
+ ret = dmabuf->ops->attach(dmabuf, dev, attach);
+ if (ret)
+ goto err_attach;
+ }
+ list_add(&attach->node, &dmabuf->attachments);
+
+ mutex_unlock(&dmabuf->lock);
+ return attach;
+
+err_attach:
+ kfree(attach);
+ mutex_unlock(&dmabuf->lock);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(dma_buf_attach);
+
+/**
+ * dma_buf_detach - Remove the given attachment from dmabuf's attachments list;
+ * optionally calls detach() of dma_buf_ops for device-specific detach
+ * @dmabuf: [in] buffer to detach from.
+ * @attach: [in] attachment to be detached; is free'd after this call.
+ *
+ */
+void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach)
+{
+ if (WARN_ON(!dmabuf || !attach))
+ return;
+
+ mutex_lock(&dmabuf->lock);
+ list_del(&attach->node);
+ if (dmabuf->ops->detach)
+ dmabuf->ops->detach(dmabuf, attach);
+
+ mutex_unlock(&dmabuf->lock);
+ kfree(attach);
+}
+EXPORT_SYMBOL_GPL(dma_buf_detach);
+
+/**
+ * dma_buf_map_attachment - Returns the scatterlist table of the attachment;
+ * mapped into _device_ address space. Is a wrapper for map_dma_buf() of the
+ * dma_buf_ops.
+ * @attach: [in] attachment whose scatterlist is to be returned
+ * @direction: [in] direction of DMA transfer
+ *
+ * Returns sg_table containing the scatterlist to be returned; returns ERR_PTR
+ * on error.
+ */
+struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach,
+ enum dma_data_direction direction)
+{
+ struct sg_table *sg_table = ERR_PTR(-EINVAL);
+
+ might_sleep();
+
+ if (WARN_ON(!attach || !attach->dmabuf))
+ return ERR_PTR(-EINVAL);
+
+ sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction);
+ if (!sg_table)
+ sg_table = ERR_PTR(-ENOMEM);
+
+ return sg_table;
+}
+EXPORT_SYMBOL_GPL(dma_buf_map_attachment);
+
+/**
+ * dma_buf_unmap_attachment - unmaps and decreases usecount of the buffer;might
+ * deallocate the scatterlist associated. Is a wrapper for unmap_dma_buf() of
+ * dma_buf_ops.
+ * @attach: [in] attachment to unmap buffer from
+ * @sg_table: [in] scatterlist info of the buffer to unmap
+ * @direction: [in] direction of DMA transfer
+ *
+ */
+void dma_buf_unmap_attachment(struct dma_buf_attachment *attach,
+ struct sg_table *sg_table,
+ enum dma_data_direction direction)
+{
+ might_sleep();
+
+ if (WARN_ON(!attach || !attach->dmabuf || !sg_table))
+ return;
+
+ attach->dmabuf->ops->unmap_dma_buf(attach, sg_table,
+ direction);
+}
+EXPORT_SYMBOL_GPL(dma_buf_unmap_attachment);
+
+
+/**
+ * dma_buf_begin_cpu_access - Must be called before accessing a dma_buf from the
+ * cpu in the kernel context. Calls begin_cpu_access to allow exporter-specific
+ * preparations. Coherency is only guaranteed in the specified range for the
+ * specified access direction.
+ * @dmabuf: [in] buffer to prepare cpu access for.
+ * @start: [in] start of range for cpu access.
+ * @len: [in] length of range for cpu access.
+ * @direction: [in] length of range for cpu access.
+ *
+ * Can return negative error values, returns 0 on success.
+ */
+int dma_buf_begin_cpu_access(struct dma_buf *dmabuf, size_t start, size_t len,
+ enum dma_data_direction direction)
+{
+ int ret = 0;
+
+ if (WARN_ON(!dmabuf))
+ return -EINVAL;
+
+ if (dmabuf->ops->begin_cpu_access)
+ ret = dmabuf->ops->begin_cpu_access(dmabuf, start, len, direction);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dma_buf_begin_cpu_access);
+
+/**
+ * dma_buf_end_cpu_access - Must be called after accessing a dma_buf from the
+ * cpu in the kernel context. Calls end_cpu_access to allow exporter-specific
+ * actions. Coherency is only guaranteed in the specified range for the
+ * specified access direction.
+ * @dmabuf: [in] buffer to complete cpu access for.
+ * @start: [in] start of range for cpu access.
+ * @len: [in] length of range for cpu access.
+ * @direction: [in] length of range for cpu access.
+ *
+ * This call must always succeed.
+ */
+void dma_buf_end_cpu_access(struct dma_buf *dmabuf, size_t start, size_t len,
+ enum dma_data_direction direction)
+{
+ WARN_ON(!dmabuf);
+
+ if (dmabuf->ops->end_cpu_access)
+ dmabuf->ops->end_cpu_access(dmabuf, start, len, direction);
+}
+EXPORT_SYMBOL_GPL(dma_buf_end_cpu_access);
+
+/**
+ * dma_buf_kmap_atomic - Map a page of the buffer object into kernel address
+ * space. The same restrictions as for kmap_atomic and friends apply.
+ * @dmabuf: [in] buffer to map page from.
+ * @page_num: [in] page in PAGE_SIZE units to map.
+ *
+ * This call must always succeed, any necessary preparations that might fail
+ * need to be done in begin_cpu_access.
+ */
+void *dma_buf_kmap_atomic(struct dma_buf *dmabuf, unsigned long page_num)
+{
+ WARN_ON(!dmabuf);
+
+ return dmabuf->ops->kmap_atomic(dmabuf, page_num);
+}
+EXPORT_SYMBOL_GPL(dma_buf_kmap_atomic);
+
+/**
+ * dma_buf_kunmap_atomic - Unmap a page obtained by dma_buf_kmap_atomic.
+ * @dmabuf: [in] buffer to unmap page from.
+ * @page_num: [in] page in PAGE_SIZE units to unmap.
+ * @vaddr: [in] kernel space pointer obtained from dma_buf_kmap_atomic.
+ *
+ * This call must always succeed.
+ */
+void dma_buf_kunmap_atomic(struct dma_buf *dmabuf, unsigned long page_num,
+ void *vaddr)
+{
+ WARN_ON(!dmabuf);
+
+ if (dmabuf->ops->kunmap_atomic)
+ dmabuf->ops->kunmap_atomic(dmabuf, page_num, vaddr);
+}
+EXPORT_SYMBOL_GPL(dma_buf_kunmap_atomic);
+
+/**
+ * dma_buf_kmap - Map a page of the buffer object into kernel address space. The
+ * same restrictions as for kmap and friends apply.
+ * @dmabuf: [in] buffer to map page from.
+ * @page_num: [in] page in PAGE_SIZE units to map.
+ *
+ * This call must always succeed, any necessary preparations that might fail
+ * need to be done in begin_cpu_access.
+ */
+void *dma_buf_kmap(struct dma_buf *dmabuf, unsigned long page_num)
+{
+ WARN_ON(!dmabuf);
+
+ return dmabuf->ops->kmap(dmabuf, page_num);
+}
+EXPORT_SYMBOL_GPL(dma_buf_kmap);
+
+/**
+ * dma_buf_kunmap - Unmap a page obtained by dma_buf_kmap.
+ * @dmabuf: [in] buffer to unmap page from.
+ * @page_num: [in] page in PAGE_SIZE units to unmap.
+ * @vaddr: [in] kernel space pointer obtained from dma_buf_kmap.
+ *
+ * This call must always succeed.
+ */
+void dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long page_num,
+ void *vaddr)
+{
+ WARN_ON(!dmabuf);
+
+ if (dmabuf->ops->kunmap)
+ dmabuf->ops->kunmap(dmabuf, page_num, vaddr);
+}
+EXPORT_SYMBOL_GPL(dma_buf_kunmap);
+
+
+/**
+ * dma_buf_mmap - Setup up a userspace mmap with the given vma
+ * @dmabuf: [in] buffer that should back the vma
+ * @vma: [in] vma for the mmap
+ * @pgoff: [in] offset in pages where this mmap should start within the
+ * dma-buf buffer.
+ *
+ * This function adjusts the passed in vma so that it points at the file of the
+ * dma_buf operation. It also adjusts the starting pgoff and does bounds
+ * checking on the size of the vma. Then it calls the exporters mmap function to
+ * set up the mapping.
+ *
+ * Can return negative error values, returns 0 on success.
+ */
+int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
+ unsigned long pgoff)
+{
+ struct file *oldfile;
+ int ret;
+
+ if (WARN_ON(!dmabuf || !vma))
+ return -EINVAL;
+
+ /* check for offset overflow */
+ if (pgoff + ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) < pgoff)
+ return -EOVERFLOW;
+
+ /* check for overflowing the buffer's size */
+ if (pgoff + ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) >
+ dmabuf->size >> PAGE_SHIFT)
+ return -EINVAL;
+
+ /* readjust the vma */
+ get_file(dmabuf->file);
+ oldfile = vma->vm_file;
+ vma->vm_file = dmabuf->file;
+ vma->vm_pgoff = pgoff;
+
+ ret = dmabuf->ops->mmap(dmabuf, vma);
+ if (ret) {
+ /* restore old parameters on failure */
+ vma->vm_file = oldfile;
+ fput(dmabuf->file);
+ } else {
+ if (oldfile)
+ fput(oldfile);
+ }
+ return ret;
+
+}
+EXPORT_SYMBOL_GPL(dma_buf_mmap);
+
+/**
+ * dma_buf_vmap - Create virtual mapping for the buffer object into kernel
+ * address space. Same restrictions as for vmap and friends apply.
+ * @dmabuf: [in] buffer to vmap
+ *
+ * This call may fail due to lack of virtual mapping address space.
+ * These calls are optional in drivers. The intended use for them
+ * is for mapping objects linear in kernel space for high use objects.
+ * Please attempt to use kmap/kunmap before thinking about these interfaces.
+ *
+ * Returns NULL on error.
+ */
+void *dma_buf_vmap(struct dma_buf *dmabuf)
+{
+ void *ptr;
+
+ if (WARN_ON(!dmabuf))
+ return NULL;
+
+ if (!dmabuf->ops->vmap)
+ return NULL;
+
+ mutex_lock(&dmabuf->lock);
+ if (dmabuf->vmapping_counter) {
+ dmabuf->vmapping_counter++;
+ BUG_ON(!dmabuf->vmap_ptr);
+ ptr = dmabuf->vmap_ptr;
+ goto out_unlock;
+ }
+
+ BUG_ON(dmabuf->vmap_ptr);
+
+ ptr = dmabuf->ops->vmap(dmabuf);
+ if (WARN_ON_ONCE(IS_ERR(ptr)))
+ ptr = NULL;
+ if (!ptr)
+ goto out_unlock;
+
+ dmabuf->vmap_ptr = ptr;
+ dmabuf->vmapping_counter = 1;
+
+out_unlock:
+ mutex_unlock(&dmabuf->lock);
+ return ptr;
+}
+EXPORT_SYMBOL_GPL(dma_buf_vmap);
+
+/**
+ * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap.
+ * @dmabuf: [in] buffer to vunmap
+ * @vaddr: [in] vmap to vunmap
+ */
+void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr)
+{
+ if (WARN_ON(!dmabuf))
+ return;
+
+ BUG_ON(!dmabuf->vmap_ptr);
+ BUG_ON(dmabuf->vmapping_counter == 0);
+ BUG_ON(dmabuf->vmap_ptr != vaddr);
+
+ mutex_lock(&dmabuf->lock);
+ if (--dmabuf->vmapping_counter == 0) {
+ if (dmabuf->ops->vunmap)
+ dmabuf->ops->vunmap(dmabuf, vaddr);
+ dmabuf->vmap_ptr = NULL;
+ }
+ mutex_unlock(&dmabuf->lock);
+}
+EXPORT_SYMBOL_GPL(dma_buf_vunmap);
+
+#ifdef CONFIG_DEBUG_FS
+static int dma_buf_describe(struct seq_file *s)
+{
+ int ret;
+ struct dma_buf *buf_obj;
+ struct dma_buf_attachment *attach_obj;
+ int count = 0, attach_count;
+ size_t size = 0;
+
+ ret = mutex_lock_interruptible(&db_list.lock);
+
+ if (ret)
+ return ret;
+
+ seq_puts(s, "\nDma-buf Objects:\n");
+ seq_puts(s, "size\tflags\tmode\tcount\texp_name\n");
+
+ list_for_each_entry(buf_obj, &db_list.head, list_node) {
+ ret = mutex_lock_interruptible(&buf_obj->lock);
+
+ if (ret) {
+ seq_puts(s,
+ "\tERROR locking buffer object: skipping\n");
+ continue;
+ }
+
+ seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\n",
+ buf_obj->size,
+ buf_obj->file->f_flags, buf_obj->file->f_mode,
+ (long)(buf_obj->file->f_count.counter),
+ buf_obj->exp_name);
+
+ seq_puts(s, "\tAttached Devices:\n");
+ attach_count = 0;
+
+ list_for_each_entry(attach_obj, &buf_obj->attachments, node) {
+ seq_puts(s, "\t");
+
+ seq_printf(s, "%s\n", dev_name(attach_obj->dev));
+ attach_count++;
+ }
+
+ seq_printf(s, "Total %d devices attached\n\n",
+ attach_count);
+
+ count++;
+ size += buf_obj->size;
+ mutex_unlock(&buf_obj->lock);
+ }
+
+ seq_printf(s, "\nTotal %d objects, %zu bytes\n", count, size);
+
+ mutex_unlock(&db_list.lock);
+ return 0;
+}
+
+static int dma_buf_show(struct seq_file *s, void *unused)
+{
+ void (*func)(struct seq_file *) = s->private;
+ func(s);
+ return 0;
+}
+
+static int dma_buf_debug_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, dma_buf_show, inode->i_private);
+}
+
+static const struct file_operations dma_buf_debug_fops = {
+ .open = dma_buf_debug_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static struct dentry *dma_buf_debugfs_dir;
+
+static int dma_buf_init_debugfs(void)
+{
+ int err = 0;
+ dma_buf_debugfs_dir = debugfs_create_dir("dma_buf", NULL);
+ if (IS_ERR(dma_buf_debugfs_dir)) {
+ err = PTR_ERR(dma_buf_debugfs_dir);
+ dma_buf_debugfs_dir = NULL;
+ return err;
+ }
+
+ err = dma_buf_debugfs_create_file("bufinfo", dma_buf_describe);
+
+ if (err)
+ pr_debug("dma_buf: debugfs: failed to create node bufinfo\n");
+
+ return err;
+}
+
+static void dma_buf_uninit_debugfs(void)
+{
+ if (dma_buf_debugfs_dir)
+ debugfs_remove_recursive(dma_buf_debugfs_dir);
+}
+
+int dma_buf_debugfs_create_file(const char *name,
+ int (*write)(struct seq_file *))
+{
+ struct dentry *d;
+
+ d = debugfs_create_file(name, S_IRUGO, dma_buf_debugfs_dir,
+ write, &dma_buf_debug_fops);
+
+ return PTR_ERR_OR_ZERO(d);
+}
+#else
+static inline int dma_buf_init_debugfs(void)
+{
+ return 0;
+}
+static inline void dma_buf_uninit_debugfs(void)
+{
+}
+#endif
+
+static int __init dma_buf_init(void)
+{
+ mutex_init(&db_list.lock);
+ INIT_LIST_HEAD(&db_list.head);
+ dma_buf_init_debugfs();
+ return 0;
+}
+subsys_initcall(dma_buf_init);
+
+static void __exit dma_buf_deinit(void)
+{
+ dma_buf_uninit_debugfs();
+}
+__exitcall(dma_buf_deinit);
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c
new file mode 100644
index 000000000000..a73fbf3b8e56
--- /dev/null
+++ b/drivers/dma-buf/reservation.c
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2012-2013 Canonical Ltd
+ *
+ * Based on bo.c which bears the following copyright notice,
+ * but is dual licensed:
+ *
+ * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+/*
+ * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
+ */
+
+#include <linux/reservation.h>
+#include <linux/export.h>
+
+DEFINE_WW_CLASS(reservation_ww_class);
+EXPORT_SYMBOL(reservation_ww_class);