remarkable-linux/include/linux/dma-debug.h
Dan Williams 0abdd7a81b dma-debug: introduce debug_dma_assert_idle()
Record actively mapped pages and provide an api for asserting a given
page is dma inactive before execution proceeds.  Placing
debug_dma_assert_idle() in cow_user_page() flagged the violation of the
dma-api in the NET_DMA implementation (see commit 7787380336 "net_dma:
mark broken").

The implementation includes the capability to count, in a limited way,
repeat mappings of the same page that occur without an intervening
unmap.  This 'overlap' counter is limited to the few bits of tag space
in a radix tree.  This mechanism is added to mitigate false negative
cases where, for example, a page is dma mapped twice and
debug_dma_assert_idle() is called after the page is un-mapped once.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:41 -08:00

195 lines
5.1 KiB
C

/*
* Copyright (C) 2008 Advanced Micro Devices, Inc.
*
* Author: Joerg Roedel <joerg.roedel@amd.com>
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef __DMA_DEBUG_H
#define __DMA_DEBUG_H
#include <linux/types.h>
struct device;
struct scatterlist;
struct bus_type;
#ifdef CONFIG_DMA_API_DEBUG
extern void dma_debug_add_bus(struct bus_type *bus);
extern void dma_debug_init(u32 num_entries);
extern int dma_debug_resize_entries(u32 num_entries);
extern void debug_dma_map_page(struct device *dev, struct page *page,
size_t offset, size_t size,
int direction, dma_addr_t dma_addr,
bool map_single);
extern void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
extern void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
size_t size, int direction, bool map_single);
extern void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
int nents, int mapped_ents, int direction);
extern void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
int nelems, int dir);
extern void debug_dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t dma_addr, void *virt);
extern void debug_dma_free_coherent(struct device *dev, size_t size,
void *virt, dma_addr_t addr);
extern void debug_dma_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle, size_t size,
int direction);
extern void debug_dma_sync_single_for_device(struct device *dev,
dma_addr_t dma_handle,
size_t size, int direction);
extern void debug_dma_sync_single_range_for_cpu(struct device *dev,
dma_addr_t dma_handle,
unsigned long offset,
size_t size,
int direction);
extern void debug_dma_sync_single_range_for_device(struct device *dev,
dma_addr_t dma_handle,
unsigned long offset,
size_t size, int direction);
extern void debug_dma_sync_sg_for_cpu(struct device *dev,
struct scatterlist *sg,
int nelems, int direction);
extern void debug_dma_sync_sg_for_device(struct device *dev,
struct scatterlist *sg,
int nelems, int direction);
extern void debug_dma_dump_mappings(struct device *dev);
extern void debug_dma_assert_idle(struct page *page);
#else /* CONFIG_DMA_API_DEBUG */
static inline void dma_debug_add_bus(struct bus_type *bus)
{
}
static inline void dma_debug_init(u32 num_entries)
{
}
static inline int dma_debug_resize_entries(u32 num_entries)
{
return 0;
}
static inline void debug_dma_map_page(struct device *dev, struct page *page,
size_t offset, size_t size,
int direction, dma_addr_t dma_addr,
bool map_single)
{
}
static inline void debug_dma_mapping_error(struct device *dev,
dma_addr_t dma_addr)
{
}
static inline void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
size_t size, int direction,
bool map_single)
{
}
static inline void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
int nents, int mapped_ents, int direction)
{
}
static inline void debug_dma_unmap_sg(struct device *dev,
struct scatterlist *sglist,
int nelems, int dir)
{
}
static inline void debug_dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t dma_addr, void *virt)
{
}
static inline void debug_dma_free_coherent(struct device *dev, size_t size,
void *virt, dma_addr_t addr)
{
}
static inline void debug_dma_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle,
size_t size, int direction)
{
}
static inline void debug_dma_sync_single_for_device(struct device *dev,
dma_addr_t dma_handle,
size_t size, int direction)
{
}
static inline void debug_dma_sync_single_range_for_cpu(struct device *dev,
dma_addr_t dma_handle,
unsigned long offset,
size_t size,
int direction)
{
}
static inline void debug_dma_sync_single_range_for_device(struct device *dev,
dma_addr_t dma_handle,
unsigned long offset,
size_t size,
int direction)
{
}
static inline void debug_dma_sync_sg_for_cpu(struct device *dev,
struct scatterlist *sg,
int nelems, int direction)
{
}
static inline void debug_dma_sync_sg_for_device(struct device *dev,
struct scatterlist *sg,
int nelems, int direction)
{
}
static inline void debug_dma_dump_mappings(struct device *dev)
{
}
static inline void debug_dma_assert_idle(struct page *page)
{
}
#endif /* CONFIG_DMA_API_DEBUG */
#endif /* __DMA_DEBUG_H */