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-rw-r--r--Documentation/DMA-API.txt106
-rw-r--r--Documentation/kernel-parameters.txt10
-rw-r--r--arch/Kconfig2
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/x86/include/asm/dma-mapping.h45
-rw-r--r--arch/x86/kernel/pci-dma.c10
-rw-r--r--include/linux/dma-debug.h174
-rw-r--r--lib/Kconfig.debug11
-rw-r--r--lib/Makefile2
-rw-r--r--lib/dma-debug.c949
10 files changed, 1304 insertions, 6 deletions
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 2a3fcc55e981..d9aa43d78bcc 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -609,3 +609,109 @@ size is the size (and should be a page-sized multiple).
The return value will be either a pointer to the processor virtual
address of the memory, or an error (via PTR_ERR()) if any part of the
region is occupied.
+
+Part III - Debug drivers use of the DMA-API
+-------------------------------------------
+
+The DMA-API as described above as some constraints. DMA addresses must be
+released with the corresponding function with the same size for example. With
+the advent of hardware IOMMUs it becomes more and more important that drivers
+do not violate those constraints. In the worst case such a violation can
+result in data corruption up to destroyed filesystems.
+
+To debug drivers and find bugs in the usage of the DMA-API checking code can
+be compiled into the kernel which will tell the developer about those
+violations. If your architecture supports it you can select the "Enable
+debugging of DMA-API usage" option in your kernel configuration. Enabling this
+option has a performance impact. Do not enable it in production kernels.
+
+If you boot the resulting kernel will contain code which does some bookkeeping
+about what DMA memory was allocated for which device. If this code detects an
+error it prints a warning message with some details into your kernel log. An
+example warning message may look like this:
+
+------------[ cut here ]------------
+WARNING: at /data2/repos/linux-2.6-iommu/lib/dma-debug.c:448
+ check_unmap+0x203/0x490()
+Hardware name:
+forcedeth 0000:00:08.0: DMA-API: device driver frees DMA memory with wrong
+ function [device address=0x00000000640444be] [size=66 bytes] [mapped as
+single] [unmapped as page]
+Modules linked in: nfsd exportfs bridge stp llc r8169
+Pid: 0, comm: swapper Tainted: G W 2.6.28-dmatest-09289-g8bb99c0 #1
+Call Trace:
+ <IRQ> [<ffffffff80240b22>] warn_slowpath+0xf2/0x130
+ [<ffffffff80647b70>] _spin_unlock+0x10/0x30
+ [<ffffffff80537e75>] usb_hcd_link_urb_to_ep+0x75/0xc0
+ [<ffffffff80647c22>] _spin_unlock_irqrestore+0x12/0x40
+ [<ffffffff8055347f>] ohci_urb_enqueue+0x19f/0x7c0
+ [<ffffffff80252f96>] queue_work+0x56/0x60
+ [<ffffffff80237e10>] enqueue_task_fair+0x20/0x50
+ [<ffffffff80539279>] usb_hcd_submit_urb+0x379/0xbc0
+ [<ffffffff803b78c3>] cpumask_next_and+0x23/0x40
+ [<ffffffff80235177>] find_busiest_group+0x207/0x8a0
+ [<ffffffff8064784f>] _spin_lock_irqsave+0x1f/0x50
+ [<ffffffff803c7ea3>] check_unmap+0x203/0x490
+ [<ffffffff803c8259>] debug_dma_unmap_page+0x49/0x50
+ [<ffffffff80485f26>] nv_tx_done_optimized+0xc6/0x2c0
+ [<ffffffff80486c13>] nv_nic_irq_optimized+0x73/0x2b0
+ [<ffffffff8026df84>] handle_IRQ_event+0x34/0x70
+ [<ffffffff8026ffe9>] handle_edge_irq+0xc9/0x150
+ [<ffffffff8020e3ab>] do_IRQ+0xcb/0x1c0
+ [<ffffffff8020c093>] ret_from_intr+0x0/0xa
+ <EOI> <4>---[ end trace f6435a98e2a38c0e ]---
+
+The driver developer can find the driver and the device including a stacktrace
+of the DMA-API call which caused this warning.
+
+Per default only the first error will result in a warning message. All other
+errors will only silently counted. This limitation exist to prevent the code
+from flooding your kernel log. To support debugging a device driver this can
+be disabled via debugfs. See the debugfs interface documentation below for
+details.
+
+The debugfs directory for the DMA-API debugging code is called dma-api/. In
+this directory the following files can currently be found:
+
+ dma-api/all_errors This file contains a numeric value. If this
+ value is not equal to zero the debugging code
+ will print a warning for every error it finds
+ into the kernel log. Be carefull with this
+ option. It can easily flood your logs.
+
+ dma-api/disabled This read-only file contains the character 'Y'
+ if the debugging code is disabled. This can
+ happen when it runs out of memory or if it was
+ disabled at boot time
+
+ dma-api/error_count This file is read-only and shows the total
+ numbers of errors found.
+
+ dma-api/num_errors The number in this file shows how many
+ warnings will be printed to the kernel log
+ before it stops. This number is initialized to
+ one at system boot and be set by writing into
+ this file
+
+ dma-api/min_free_entries
+ This read-only file can be read to get the
+ minimum number of free dma_debug_entries the
+ allocator has ever seen. If this value goes
+ down to zero the code will disable itself
+ because it is not longer reliable.
+
+ dma-api/num_free_entries
+ The current number of free dma_debug_entries
+ in the allocator.
+
+If you have this code compiled into your kernel it will be enabled by default.
+If you want to boot without the bookkeeping anyway you can provide
+'dma_debug=off' as a boot parameter. This will disable DMA-API debugging.
+Notice that you can not enable it again at runtime. You have to reboot to do
+so.
+
+When the code disables itself at runtime this is most likely because it ran
+out of dma_debug_entries. These entries are preallocated at boot. The number
+of preallocated entries is defined per architecture. If it is too low for you
+boot with 'dma_debug_entries=<your_desired_number>' to overwrite the
+architectural default.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 54f21a5c262b..0fa3c0545994 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -491,6 +491,16 @@ and is between 256 and 4096 characters. It is defined in the file
Range: 0 - 8192
Default: 64
+ dma_debug=off If the kernel is compiled with DMA_API_DEBUG support
+ this option disables the debugging code at boot.
+
+ dma_debug_entries=<number>
+ This option allows to tune the number of preallocated
+ entries for DMA-API debugging code. One entry is
+ required per DMA-API allocation. Use this if the
+ DMA-API debugging code disables itself because the
+ architectural default is too low.
+
hpet= [X86-32,HPET] option to control HPET usage
Format: { enable (default) | disable | force }
disable: disable HPET and use PIT instead
diff --git a/arch/Kconfig b/arch/Kconfig
index 550dab22daa1..830c16a2b801 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -106,3 +106,5 @@ config HAVE_CLK
The <linux/clk.h> calls support software clock gating and
thus are a key power management tool on many systems.
+config HAVE_DMA_API_DEBUG
+ bool
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index bc2fbadff9f9..f2cb677b263f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -40,6 +40,7 @@ config X86
select HAVE_GENERIC_DMA_COHERENT if X86_32
select HAVE_EFFICIENT_UNALIGNED_ACCESS
select USER_STACKTRACE_SUPPORT
+ select HAVE_DMA_API_DEBUG
config ARCH_DEFCONFIG
string
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 9c78bd40ebec..cea7b74963e9 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -7,6 +7,7 @@
*/
#include <linux/scatterlist.h>
+#include <linux/dma-debug.h>
#include <linux/dma-attrs.h>
#include <asm/io.h>
#include <asm/swiotlb.h>
@@ -56,11 +57,16 @@ dma_map_single(struct device *hwdev, void *ptr, size_t size,
enum dma_data_direction dir)
{
struct dma_map_ops *ops = get_dma_ops(hwdev);
+ dma_addr_t addr;
BUG_ON(!valid_dma_direction(dir));
- return ops->map_page(hwdev, virt_to_page(ptr),
+ addr = ops->map_page(hwdev, virt_to_page(ptr),
(unsigned long)ptr & ~PAGE_MASK, size,
dir, NULL);
+ debug_dma_map_page(hwdev, virt_to_page(ptr),
+ (unsigned long)ptr & ~PAGE_MASK, size,
+ dir, addr, true);
+ return addr;
}
static inline void
@@ -72,6 +78,7 @@ dma_unmap_single(struct device *dev, dma_addr_t addr, size_t size,
BUG_ON(!valid_dma_direction(dir));
if (ops->unmap_page)
ops->unmap_page(dev, addr, size, dir, NULL);
+ debug_dma_unmap_page(dev, addr, size, dir, true);
}
static inline int
@@ -79,9 +86,13 @@ dma_map_sg(struct device *hwdev, struct scatterlist *sg,
int nents, enum dma_data_direction dir)
{
struct dma_map_ops *ops = get_dma_ops(hwdev);
+ int ents;
BUG_ON(!valid_dma_direction(dir));
- return ops->map_sg(hwdev, sg, nents, dir, NULL);
+ ents = ops->map_sg(hwdev, sg, nents, dir, NULL);
+ debug_dma_map_sg(hwdev, sg, nents, ents, dir);
+
+ return ents;
}
static inline void
@@ -91,6 +102,7 @@ dma_unmap_sg(struct device *hwdev, struct scatterlist *sg, int nents,
struct dma_map_ops *ops = get_dma_ops(hwdev);
BUG_ON(!valid_dma_direction(dir));
+ debug_dma_unmap_sg(hwdev, sg, nents, dir);
if (ops->unmap_sg)
ops->unmap_sg(hwdev, sg, nents, dir, NULL);
}
@@ -104,6 +116,7 @@ dma_sync_single_for_cpu(struct device *hwdev, dma_addr_t dma_handle,
BUG_ON(!valid_dma_direction(dir));
if (ops->sync_single_for_cpu)
ops->sync_single_for_cpu(hwdev, dma_handle, size, dir);
+ debug_dma_sync_single_for_cpu(hwdev, dma_handle, size, dir);
flush_write_buffers();
}
@@ -116,6 +129,7 @@ dma_sync_single_for_device(struct device *hwdev, dma_addr_t dma_handle,
BUG_ON(!valid_dma_direction(dir));
if (ops->sync_single_for_device)
ops->sync_single_for_device(hwdev, dma_handle, size, dir);
+ debug_dma_sync_single_for_device(hwdev, dma_handle, size, dir);
flush_write_buffers();
}
@@ -130,6 +144,8 @@ dma_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dma_handle,
if (ops->sync_single_range_for_cpu)
ops->sync_single_range_for_cpu(hwdev, dma_handle, offset,
size, dir);
+ debug_dma_sync_single_range_for_cpu(hwdev, dma_handle,
+ offset, size, dir);
flush_write_buffers();
}
@@ -144,6 +160,8 @@ dma_sync_single_range_for_device(struct device *hwdev, dma_addr_t dma_handle,
if (ops->sync_single_range_for_device)
ops->sync_single_range_for_device(hwdev, dma_handle,
offset, size, dir);
+ debug_dma_sync_single_range_for_device(hwdev, dma_handle,
+ offset, size, dir);
flush_write_buffers();
}
@@ -156,6 +174,7 @@ dma_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
BUG_ON(!valid_dma_direction(dir));
if (ops->sync_sg_for_cpu)
ops->sync_sg_for_cpu(hwdev, sg, nelems, dir);
+ debug_dma_sync_sg_for_cpu(hwdev, sg, nelems, dir);
flush_write_buffers();
}
@@ -168,6 +187,7 @@ dma_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
BUG_ON(!valid_dma_direction(dir));
if (ops->sync_sg_for_device)
ops->sync_sg_for_device(hwdev, sg, nelems, dir);
+ debug_dma_sync_sg_for_device(hwdev, sg, nelems, dir);
flush_write_buffers();
}
@@ -177,15 +197,24 @@ static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
enum dma_data_direction dir)
{
struct dma_map_ops *ops = get_dma_ops(dev);
+ dma_addr_t addr;
BUG_ON(!valid_dma_direction(dir));
- return ops->map_page(dev, page, offset, size, dir, NULL);
+ addr = ops->map_page(dev, page, offset, size, dir, NULL);
+ debug_dma_map_page(dev, page, offset, size, dir, addr, false);
+
+ return addr;
}
static inline void dma_unmap_page(struct device *dev, dma_addr_t addr,
size_t size, enum dma_data_direction dir)
{
- dma_unmap_single(dev, addr, size, dir);
+ struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (ops->unmap_page)
+ ops->unmap_page(dev, addr, size, dir, NULL);
+ debug_dma_unmap_page(dev, addr, size, dir, false);
}
static inline void
@@ -250,8 +279,11 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
if (!ops->alloc_coherent)
return NULL;
- return ops->alloc_coherent(dev, size, dma_handle,
- dma_alloc_coherent_gfp_flags(dev, gfp));
+ memory = ops->alloc_coherent(dev, size, dma_handle,
+ dma_alloc_coherent_gfp_flags(dev, gfp));
+ debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
+
+ return memory;
}
static inline void dma_free_coherent(struct device *dev, size_t size,
@@ -264,6 +296,7 @@ static inline void dma_free_coherent(struct device *dev, size_t size,
if (dma_release_from_coherent(dev, get_order(size), vaddr))
return;
+ debug_dma_free_coherent(dev, size, vaddr, bus);
if (ops->free_coherent)
ops->free_coherent(dev, size, vaddr, bus);
}
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index f293a8df6828..c7c4776ff630 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -1,4 +1,5 @@
#include <linux/dma-mapping.h>
+#include <linux/dma-debug.h>
#include <linux/dmar.h>
#include <linux/bootmem.h>
#include <linux/pci.h>
@@ -44,6 +45,9 @@ struct device x86_dma_fallback_dev = {
};
EXPORT_SYMBOL(x86_dma_fallback_dev);
+/* Number of entries preallocated for DMA-API debugging */
+#define PREALLOC_DMA_DEBUG_ENTRIES 32768
+
int dma_set_mask(struct device *dev, u64 mask)
{
if (!dev->dma_mask || !dma_supported(dev, mask))
@@ -265,6 +269,12 @@ EXPORT_SYMBOL(dma_supported);
static int __init pci_iommu_init(void)
{
+ dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
+
+#ifdef CONFIG_PCI
+ dma_debug_add_bus(&pci_bus_type);
+#endif
+
calgary_iommu_init();
intel_iommu_init();
diff --git a/include/linux/dma-debug.h b/include/linux/dma-debug.h
new file mode 100644
index 000000000000..e851d23e91eb
--- /dev/null
+++ b/include/linux/dma-debug.h
@@ -0,0 +1,174 @@
+/*
+ * 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 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_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);
+
+#else /* CONFIG_DMA_API_DEBUG */
+
+void dma_debug_add_bus(struct bus_type *bus)
+{
+}
+
+static inline void dma_debug_init(u32 num_entries)
+{
+}
+
+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_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)
+{
+}
+
+#endif /* CONFIG_DMA_API_DEBUG */
+
+#endif /* __DMA_DEBUG_H */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 1bcf9cd4baa0..d9cbada7e2f8 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -902,6 +902,17 @@ config DYNAMIC_PRINTK_DEBUG
debugging for all modules. This mode can be turned off via the above
disable command.
+config DMA_API_DEBUG
+ bool "Enable debugging of DMA-API usage"
+ depends on HAVE_DMA_API_DEBUG
+ help
+ Enable this option to debug the use of the DMA API by device drivers.
+ With this option you will be able to detect common bugs in device
+ drivers like double-freeing of DMA mappings or freeing mappings that
+ were never allocated.
+ This option causes a performance degredation. Use only if you want
+ to debug device drivers. If unsure, say N.
+
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
diff --git a/lib/Makefile b/lib/Makefile
index 32b0e64ded27..50b48cf63e4a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -84,6 +84,8 @@ obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o
obj-$(CONFIG_DYNAMIC_PRINTK_DEBUG) += dynamic_printk.o
+obj-$(CONFIG_DMA_API_DEBUG) += dma-debug.o
+
hostprogs-y := gen_crc32table
clean-files := crc32table.h
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
new file mode 100644
index 000000000000..9a350b414a50
--- /dev/null
+++ b/lib/dma-debug.c
@@ -0,0 +1,949 @@
+/*
+ * 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
+ */
+
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <linux/stacktrace.h>
+#include <linux/dma-debug.h>
+#include <linux/spinlock.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include <asm/sections.h>
+
+#define HASH_SIZE 1024ULL
+#define HASH_FN_SHIFT 13
+#define HASH_FN_MASK (HASH_SIZE - 1)
+
+enum {
+ dma_debug_single,
+ dma_debug_page,
+ dma_debug_sg,
+ dma_debug_coherent,
+};
+
+#define DMA_DEBUG_STACKTRACE_ENTRIES 5
+
+struct dma_debug_entry {
+ struct list_head list;
+ struct device *dev;
+ int type;
+ phys_addr_t paddr;
+ u64 dev_addr;
+ u64 size;
+ int direction;
+ int sg_call_ents;
+ int sg_mapped_ents;
+#ifdef CONFIG_STACKTRACE
+ struct stack_trace stacktrace;
+ unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES];
+#endif
+};
+
+struct hash_bucket {
+ struct list_head list;
+ spinlock_t lock;
+} ____cacheline_aligned_in_smp;
+
+/* Hash list to save the allocated dma addresses */
+static struct hash_bucket dma_entry_hash[HASH_SIZE];
+/* List of pre-allocated dma_debug_entry's */
+static LIST_HEAD(free_entries);
+/* Lock for the list above */
+static DEFINE_SPINLOCK(free_entries_lock);
+
+/* Global disable flag - will be set in case of an error */
+static bool global_disable __read_mostly;
+
+/* Global error count */
+static u32 error_count;
+
+/* Global error show enable*/
+static u32 show_all_errors __read_mostly;
+/* Number of errors to show */
+static u32 show_num_errors = 1;
+
+static u32 num_free_entries;
+static u32 min_free_entries;
+
+/* number of preallocated entries requested by kernel cmdline */
+static u32 req_entries;
+
+/* debugfs dentry's for the stuff above */
+static struct dentry *dma_debug_dent __read_mostly;
+static struct dentry *global_disable_dent __read_mostly;
+static struct dentry *error_count_dent __read_mostly;
+static struct dentry *show_all_errors_dent __read_mostly;
+static struct dentry *show_num_errors_dent __read_mostly;
+static struct dentry *num_free_entries_dent __read_mostly;
+static struct dentry *min_free_entries_dent __read_mostly;
+
+static const char *type2name[4] = { "single", "page",
+ "scather-gather", "coherent" };
+
+static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
+ "DMA_FROM_DEVICE", "DMA_NONE" };
+
+/*
+ * The access to some variables in this macro is racy. We can't use atomic_t
+ * here because all these variables are exported to debugfs. Some of them even
+ * writeable. This is also the reason why a lock won't help much. But anyway,
+ * the races are no big deal. Here is why:
+ *
+ * error_count: the addition is racy, but the worst thing that can happen is
+ * that we don't count some errors
+ * show_num_errors: the subtraction is racy. Also no big deal because in
+ * worst case this will result in one warning more in the
+ * system log than the user configured. This variable is
+ * writeable via debugfs.
+ */
+static inline void dump_entry_trace(struct dma_debug_entry *entry)
+{
+#ifdef CONFIG_STACKTRACE
+ if (entry) {
+ printk(KERN_WARNING "Mapped at:\n");
+ print_stack_trace(&entry->stacktrace, 0);
+ }
+#endif
+}
+
+#define err_printk(dev, entry, format, arg...) do { \
+ error_count += 1; \
+ if (show_all_errors || show_num_errors > 0) { \
+ WARN(1, "%s %s: " format, \
+ dev_driver_string(dev), \
+ dev_name(dev) , ## arg); \
+ dump_entry_trace(entry); \
+ } \
+ if (!show_all_errors && show_num_errors > 0) \
+ show_num_errors -= 1; \
+ } while (0);
+
+/*
+ * Hash related functions
+ *
+ * Every DMA-API request is saved into a struct dma_debug_entry. To
+ * have quick access to these structs they are stored into a hash.
+ */
+static int hash_fn(struct dma_debug_entry *entry)
+{
+ /*
+ * Hash function is based on the dma address.
+ * We use bits 20-27 here as the index into the hash
+ */
+ return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK;
+}
+
+/*
+ * Request exclusive access to a hash bucket for a given dma_debug_entry.
+ */
+static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry,
+ unsigned long *flags)
+{
+ int idx = hash_fn(entry);
+ unsigned long __flags;
+
+ spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags);
+ *flags = __flags;
+ return &dma_entry_hash[idx];
+}
+
+/*
+ * Give up exclusive access to the hash bucket
+ */
+static void put_hash_bucket(struct hash_bucket *bucket,
+ unsigned long *flags)
+{
+ unsigned long __flags = *flags;
+
+ spin_unlock_irqrestore(&bucket->lock, __flags);
+}
+
+/*
+ * Search a given entry in the hash bucket list
+ */
+static struct dma_debug_entry *hash_bucket_find(struct hash_bucket *bucket,
+ struct dma_debug_entry *ref)
+{
+ struct dma_debug_entry *entry;
+
+ list_for_each_entry(entry, &bucket->list, list) {
+ if ((entry->dev_addr == ref->dev_addr) &&
+ (entry->dev == ref->dev))
+ return entry;
+ }
+
+ return NULL;
+}
+
+/*
+ * Add an entry to a hash bucket
+ */
+static void hash_bucket_add(struct hash_bucket *bucket,
+ struct dma_debug_entry *entry)
+{
+ list_add_tail(&entry->list, &bucket->list);
+}
+
+/*
+ * Remove entry from a hash bucket list
+ */
+static void hash_bucket_del(struct dma_debug_entry *entry)
+{
+ list_del(&entry->list);
+}
+
+/*
+ * Dump mapping entries for debugging purposes
+ */
+void debug_dma_dump_mappings(struct device *dev)
+{
+ int idx;
+
+ for (idx = 0; idx < HASH_SIZE; idx++) {
+ struct hash_bucket *bucket = &dma_entry_hash[idx];
+ struct dma_debug_entry *entry;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bucket->lock, flags);
+
+ list_for_each_entry(entry, &bucket->list, list) {
+ if (!dev || dev == entry->dev) {
+ dev_info(entry->dev,
+ "%s idx %d P=%Lx D=%Lx L=%Lx %s\n",
+ type2name[entry->type], idx,
+ (unsigned long long)entry->paddr,
+ entry->dev_addr, entry->size,
+ dir2name[entry->direction]);
+ }
+ }
+
+ spin_unlock_irqrestore(&bucket->lock, flags);
+ }
+}
+EXPORT_SYMBOL(debug_dma_dump_mappings);
+
+/*
+ * Wrapper function for adding an entry to the hash.
+ * This function takes care of locking itself.
+ */
+static void add_dma_entry(struct dma_debug_entry *entry)
+{
+ struct hash_bucket *bucket;
+ unsigned long flags;
+
+ bucket = get_hash_bucket(entry, &flags);
+ hash_bucket_add(bucket, entry);
+ put_hash_bucket(bucket, &flags);
+}
+
+/* struct dma_entry allocator
+ *
+ * The next two functions implement the allocator for
+ * struct dma_debug_entries.
+ */
+static struct dma_debug_entry *dma_entry_alloc(void)
+{
+ struct dma_debug_entry *entry = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&free_entries_lock, flags);
+
+ if (list_empty(&free_entries)) {
+ printk(KERN_ERR "DMA-API: debugging out of memory "
+ "- disabling\n");
+ global_disable = true;
+ goto out;
+ }
+
+ entry = list_entry(free_entries.next, struct dma_debug_entry, list);
+ list_del(&entry->list);
+ memset(entry, 0, sizeof(*entry));
+
+#ifdef CONFIG_STACKTRACE
+ entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
+ entry->stacktrace.entries = entry->st_entries;
+ entry->stacktrace.skip = 2;
+ save_stack_trace(&entry->stacktrace);
+#endif
+ num_free_entries -= 1;
+ if (num_free_entries < min_free_entries)
+ min_free_entries = num_free_entries;
+
+out:
+ spin_unlock_irqrestore(&free_entries_lock, flags);
+
+ return entry;
+}
+
+static void dma_entry_free(struct dma_debug_entry *entry)
+{
+ unsigned long flags;
+
+ /*
+ * add to beginning of the list - this way the entries are
+ * more likely cache hot when they are reallocated.
+ */
+ spin_lock_irqsave(&free_entries_lock, flags);
+ list_add(&entry->list, &free_entries);
+ num_free_entries += 1;
+ spin_unlock_irqrestore(&free_entries_lock, flags);
+}
+
+/*
+ * DMA-API debugging init code
+ *
+ * The init code does two things:
+ * 1. Initialize core data structures
+ * 2. Preallocate a given number of dma_debug_entry structs
+ */
+
+static int prealloc_memory(u32 num_entries)
+{
+ struct dma_debug_entry *entry, *next_entry;
+ int i;
+
+ for (i = 0; i < num_entries; ++i) {
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto out_err;
+
+ list_add_tail(&entry->list, &free_entries);
+ }
+
+ num_free_entries = num_entries;
+ min_free_entries = num_entries;
+
+ printk(KERN_INFO "DMA-API: preallocated %d debug entries\n",
+ num_entries);
+
+ return 0;
+
+out_err:
+
+ list_for_each_entry_safe(entry, next_entry, &free_entries, list) {
+ list_del(&entry->list);
+ kfree(entry);
+ }
+
+ return -ENOMEM;
+}
+
+static int dma_debug_fs_init(void)
+{
+ dma_debug_dent = debugfs_create_dir("dma-api", NULL);
+ if (!dma_debug_dent) {
+ printk(KERN_ERR "DMA-API: can not create debugfs directory\n");
+ return -ENOMEM;
+ }
+
+ global_disable_dent = debugfs_create_bool("disabled", 0444,
+ dma_debug_dent,
+ (u32 *)&global_disable);
+ if (!global_disable_dent)
+ goto out_err;
+
+ error_count_dent = debugfs_create_u32("error_count", 0444,
+ dma_debug_dent, &error_count);
+ if (!error_count_dent)
+ goto out_err;
+
+ show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
+ dma_debug_dent,
+ &show_all_errors);
+ if (!show_all_errors_dent)
+ goto out_err;
+
+ show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
+ dma_debug_dent,
+ &show_num_errors);
+ if (!show_num_errors_dent)
+ goto out_err;
+
+ num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
+ dma_debug_dent,
+ &num_free_entries);
+ if (!num_free_entries_dent)
+ goto out_err;
+
+ min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
+ dma_debug_dent,
+ &min_free_entries);
+ if (!min_free_entries_dent)
+ goto out_err;
+
+ return 0;
+
+out_err:
+ debugfs_remove_recursive(dma_debug_dent);
+
+ return -ENOMEM;
+}
+
+static int device_dma_allocations(struct device *dev)
+{
+ struct dma_debug_entry *entry;
+ unsigned long flags;
+ int count = 0, i;
+
+ for (i = 0; i < HASH_SIZE; ++i) {
+ spin_lock_irqsave(&dma_entry_hash[i].lock, flags);
+ list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
+ if (entry->dev == dev)
+ count += 1;
+ }
+ spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags);
+ }
+
+ return count;
+}
+
+static int dma_debug_device_change(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ int count;
+
+
+ switch (action) {
+ case BUS_NOTIFY_UNBIND_DRIVER:
+ count = device_dma_allocations(dev);
+ if (count == 0)
+ break;
+ err_printk(dev, NULL, "DMA-API: device driver has pending "
+ "DMA allocations while released from device "
+ "[count=%d]\n", count);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+void dma_debug_add_bus(struct bus_type *bus)
+{
+ struct notifier_block *nb;
+
+ nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
+ if (nb == NULL) {
+ printk(KERN_ERR "dma_debug_add_bus: out of memory\n");
+ return;
+ }
+
+ nb->notifier_call = dma_debug_device_change;
+
+ bus_register_notifier(bus, nb);
+}
+
+/*
+ * Let the architectures decide how many entries should be preallocated.
+ */
+void dma_debug_init(u32 num_entries)
+{
+ int i;
+
+ if (global_disable)
+ return;
+
+ for (i = 0; i < HASH_SIZE; ++i) {
+ INIT_LIST_HEAD(&dma_entry_hash[i].list);
+ dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
+ }
+
+ if (dma_debug_fs_init() != 0) {
+ printk(KERN_ERR "DMA-API: error creating debugfs entries "
+ "- disabling\n");
+ global_disable = true;
+
+ return;
+ }
+
+ if (req_entries)
+ num_entries = req_entries;
+
+ if (prealloc_memory(num_entries) != 0) {
+ printk(KERN_ERR "DMA-API: debugging out of memory error "
+ "- disabled\n");
+ global_disable = true;
+
+ return;
+ }
+
+ printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n");
+}
+
+static __init int dma_debug_cmdline(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (strncmp(str, "off", 3) == 0) {
+ printk(KERN_INFO "DMA-API: debugging disabled on kernel "
+ "command line\n");
+ global_disable = true;
+ }
+
+ return 0;
+}
+
+static __init int dma_debug_entries_cmdline(char *str)
+{
+ int res;
+
+ if (!str)
+ return -EINVAL;
+
+ res = get_option(&str, &req_entries);
+
+ if (!res)
+ req_entries = 0;
+
+ return 0;
+}
+
+__setup("dma_debug=", dma_debug_cmdline);
+__setup("dma_debug_entries=", dma_debug_entries_cmdline);
+
+static void check_unmap(struct dma_debug_entry *ref)
+{
+ struct dma_debug_entry *entry;
+ struct hash_bucket *bucket;
+ unsigned long flags;
+
+ if (dma_mapping_error(ref->dev, ref->dev_addr))
+ return;
+
+ bucket = get_hash_bucket(ref, &flags);
+ entry = hash_bucket_find(bucket, ref);
+
+ if (!entry) {
+ err_printk(ref->dev, NULL, "DMA-API: device driver tries "
+ "to free DMA memory it has not allocated "
+ "[device address=0x%016llx] [size=%llu bytes]\n",
+ ref->dev_addr, ref->size);
+ goto out;
+ }
+
+ if (ref->size != entry->size) {
+ err_printk(ref->dev, entry, "DMA-API: device driver frees "
+ "DMA memory with different size "
+ "[device address=0x%016llx] [map size=%llu bytes] "
+ "[unmap size=%llu bytes]\n",
+ ref->dev_addr, entry->size, ref->size);
+ }
+
+ if (ref->type != entry->type) {
+ err_printk(ref->dev, entry, "DMA-API: device driver frees "
+ "DMA memory with wrong function "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[mapped as %s] [unmapped as %s]\n",
+ ref->dev_addr, ref->size,
+ type2name[entry->type], type2name[ref->type]);
+ } else if ((entry->type == dma_debug_coherent) &&
+ (ref->paddr != entry->paddr)) {
+ err_printk(ref->dev, entry, "DMA-API: device driver frees "
+ "DMA memory with different CPU address "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[cpu alloc address=%p] [cpu free address=%p]",
+ ref->dev_addr, ref->size,
+ (void *)entry->paddr, (void *)ref->paddr);
+ }
+
+ if (ref->sg_call_ents && ref->type == dma_debug_sg &&
+ ref->sg_call_ents != entry->sg_call_ents) {
+ err_printk(ref->dev, entry, "DMA-API: device driver frees "
+ "DMA sg list with different entry count "
+ "[map count=%d] [unmap count=%d]\n",
+ entry->sg_call_ents, ref->sg_call_ents);
+ }
+
+ /*
+ * This may be no bug in reality - but most implementations of the
+ * DMA API don't handle this properly, so check for it here
+ */
+ if (ref->direction != entry->direction) {
+ err_printk(ref->dev, entry, "DMA-API: device driver frees "
+ "DMA memory with different direction "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[mapped with %s] [unmapped with %s]\n",
+ ref->dev_addr, ref->size,
+ dir2name[entry->direction],
+ dir2name[ref->direction]);
+ }
+
+ hash_bucket_del(entry);
+ dma_entry_free(entry);
+
+out:
+ put_hash_bucket(bucket, &flags);
+}
+
+static void check_for_stack(struct device *dev, void *addr)
+{
+ if (object_is_on_stack(addr))
+ err_printk(dev, NULL, "DMA-API: device driver maps memory from"
+ "stack [addr=%p]\n", addr);
+}
+
+static inline bool overlap(void *addr, u64 size, void *start, void *end)
+{
+ void *addr2 = (char *)addr + size;
+
+ return ((addr >= start && addr < end) ||
+ (addr2 >= start && addr2 < end) ||
+ ((addr < start) && (addr2 >= end)));
+}
+
+static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
+{
+ if (overlap(addr, size, _text, _etext) ||
+ overlap(addr, size, __start_rodata, __end_rodata))
+ err_printk(dev, NULL, "DMA-API: device driver maps "
+ "memory from kernel text or rodata "
+ "[addr=%p] [size=%llu]\n", addr, size);
+}
+
+static void check_sync(struct device *dev, dma_addr_t addr,
+ u64 size, u64 offset, int direction, bool to_cpu)
+{
+ struct dma_debug_entry ref = {
+ .dev = dev,
+ .dev_addr = addr,
+ .size = size,
+ .direction = direction,
+ };
+ struct dma_debug_entry *entry;
+ struct hash_bucket *bucket;
+ unsigned long flags;
+
+ bucket = get_hash_bucket(&ref, &flags);
+
+ entry = hash_bucket_find(bucket, &ref);
+
+ if (!entry) {
+ err_printk(dev, NULL, "DMA-API: device driver tries "
+ "to sync DMA memory it has not allocated "
+ "[device address=0x%016llx] [size=%llu bytes]\n",
+ addr, size);
+ goto out;
+ }
+
+ if ((offset + size) > entry->size) {
+ err_printk(dev, entry, "DMA-API: device driver syncs"
+ " DMA memory outside allocated range "
+ "[device address=0x%016llx] "
+ "[allocation size=%llu bytes] [sync offset=%llu] "
+ "[sync size=%llu]\n", entry->dev_addr, entry->size,
+ offset, size);
+ }
+
+ if (direction != entry->direction) {
+ err_printk(dev, entry, "DMA-API: device driver syncs "
+ "DMA memory with different direction "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[mapped with %s] [synced with %s]\n",
+ addr, entry->size,
+ dir2name[entry->direction],
+ dir2name[direction]);
+ }
+
+ if (entry->direction == DMA_BIDIRECTIONAL)
+ goto out;
+
+ if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
+ !(direction == DMA_TO_DEVICE))
+ err_printk(dev, entry, "DMA-API: device driver syncs "
+ "device read-only DMA memory for cpu "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[mapped with %s] [synced with %s]\n",
+ addr, entry->size,
+ dir2name[entry->direction],
+ dir2name[direction]);
+
+ if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
+ !(direction == DMA_FROM_DEVICE))
+ err_printk(dev, entry, "DMA-API: device driver syncs "
+ "device write-only DMA memory to device "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[mapped with %s] [synced with %s]\n",
+ addr, entry->size,
+ dir2name[entry->direction],
+ dir2name[direction]);
+
+out:
+ put_hash_bucket(bucket, &flags);
+
+}
+
+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)
+{
+ struct dma_debug_entry *entry;
+
+ if (unlikely(global_disable))
+ return;
+
+ if (unlikely(dma_mapping_error(dev, dma_addr)))
+ return;
+
+ entry = dma_entry_alloc();
+ if (!entry)
+ return;
+
+ entry->dev = dev;
+ entry->type = dma_debug_page;
+ entry->paddr = page_to_phys(page) + offset;
+ entry->dev_addr = dma_addr;
+ entry->size = size;
+ entry->direction = direction;
+
+ if (map_single) {
+ void *addr = ((char *)page_address(page)) + offset;
+
+ entry->type = dma_debug_single;
+ check_for_stack(dev, addr);
+ check_for_illegal_area(dev, addr, size);
+ }
+
+ add_dma_entry(entry);
+}
+EXPORT_SYMBOL(debug_dma_map_page);
+
+void debug_dma_unmap_page(struct device *dev, dma_addr_t addr,
+ size_t size, int direction, bool map_single)
+{
+ struct dma_debug_entry ref = {
+ .type = dma_debug_page,
+ .dev = dev,
+ .dev_addr = addr,
+ .size = size,
+ .direction = direction,
+ };
+
+ if (unlikely(global_disable))
+ return;
+
+ if (map_single)
+ ref.type = dma_debug_single;
+
+ check_unmap(&ref);
+}
+EXPORT_SYMBOL(debug_dma_unmap_page);
+
+void debug_dma_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, int mapped_ents, int direction)
+{
+ struct dma_debug_entry *entry;
+ struct scatterlist *s;
+ int i;
+
+ if (unlikely(global_disable))
+ return;
+
+ for_each_sg(sg, s, mapped_ents, i) {
+ entry = dma_entry_alloc();
+ if (!entry)
+ return;
+
+ entry->type = dma_debug_sg;
+ entry->dev = dev;
+ entry->paddr = sg_phys(s);
+ entry->size = s->length;
+ entry->dev_addr = s->dma_address;
+ entry->direction = direction;
+ entry->sg_call_ents = nents;
+ entry->sg_mapped_ents = mapped_ents;
+
+ check_for_stack(dev, sg_virt(s));
+ check_for_illegal_area(dev, sg_virt(s), s->length);
+
+ add_dma_entry(entry);
+ }
+}
+EXPORT_SYMBOL(debug_dma_map_sg);
+
+void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, int dir)
+{
+ struct dma_debug_entry *entry;
+ struct scatterlist *s;
+ int mapped_ents = 0, i;
+ unsigned long flags;
+
+ if (unlikely(global_disable))
+ return;
+
+ for_each_sg(sglist, s, nelems, i) {
+
+ struct dma_debug_entry ref = {
+ .type = dma_debug_sg,
+ .dev = dev,
+ .paddr = sg_phys(s),
+ .dev_addr = s->dma_address,
+ .size = s->length,
+ .direction = dir,
+ .sg_call_ents = 0,
+ };
+
+ if (mapped_ents && i >= mapped_ents)
+ break;
+
+ if (mapped_ents == 0) {
+ struct hash_bucket *bucket;
+ ref.sg_call_ents = nelems;
+ bucket = get_hash_bucket(&ref, &flags);
+ entry = hash_bucket_find(bucket, &ref);
+ if (entry)
+ mapped_ents = entry->sg_mapped_ents;
+ put_hash_bucket(bucket, &flags);
+ }
+
+ check_unmap(&ref);
+ }
+}
+EXPORT_SYMBOL(debug_dma_unmap_sg);
+
+void debug_dma_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t dma_addr, void *virt)
+{
+ struct dma_debug_entry *entry;
+
+ if (unlikely(global_disable))
+ return;
+
+ if (unlikely(virt == NULL))
+ return;
+
+ entry = dma_entry_alloc();
+ if (!entry)
+ return;
+
+ entry->type = dma_debug_coherent;
+ entry->dev = dev;
+ entry->paddr = virt_to_phys(virt);
+ entry->size = size;
+ entry->dev_addr = dma_addr;
+ entry->direction = DMA_BIDIRECTIONAL;
+
+ add_dma_entry(entry);
+}
+EXPORT_SYMBOL(debug_dma_alloc_coherent);
+
+void debug_dma_free_coherent(struct device *dev, size_t size,
+ void *virt, dma_addr_t addr)
+{
+ struct dma_debug_entry ref = {
+ .type = dma_debug_coherent,
+ .dev = dev,
+ .paddr = virt_to_phys(virt),
+ .dev_addr = addr,
+ .size = size,
+ .direction = DMA_BIDIRECTIONAL,
+ };
+
+ if (unlikely(global_disable))
+ return;
+
+ check_unmap(&ref);
+}
+EXPORT_SYMBOL(debug_dma_free_coherent);
+
+void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
+ size_t size, int direction)
+{
+ if (unlikely(global_disable))
+ return;
+
+ check_sync(dev, dma_handle, size, 0, direction, true);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_for_cpu);
+
+void debug_dma_sync_single_for_device(struct device *dev,
+ dma_addr_t dma_handle, size_t size,
+ int direction)
+{
+ if (unlikely(global_disable))
+ return;
+
+ check_sync(dev, dma_handle, size, 0, direction, false);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_for_device);
+
+void debug_dma_sync_single_range_for_cpu(struct device *dev,
+ dma_addr_t dma_handle,
+ unsigned long offset, size_t size,
+ int direction)
+{
+ if (unlikely(global_disable))
+ return;
+
+ check_sync(dev, dma_handle, size, offset, direction, true);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu);
+
+void debug_dma_sync_single_range_for_device(struct device *dev,
+ dma_addr_t dma_handle,
+ unsigned long offset,
+ size_t size, int direction)
+{
+ if (unlikely(global_disable))
+ return;
+
+ check_sync(dev, dma_handle, size, offset, direction, false);
+}
+EXPORT_SYMBOL(debug_dma_sync_single_range_for_device);
+
+void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+ int nelems, int direction)
+{
+ struct scatterlist *s;
+ int i;
+
+ if (unlikely(global_disable))
+ return;
+
+ for_each_sg(sg, s, nelems, i) {
+ check_sync(dev, s->dma_address, s->dma_length, 0,
+ direction, true);
+ }
+}
+EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu);
+
+void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+ int nelems, int direction)
+{
+ struct scatterlist *s;
+ int i;
+
+ if (unlikely(global_disable))
+ return;
+
+ for_each_sg(sg, s, nelems, i) {
+ check_sync(dev, s->dma_address, s->dma_length, 0,
+ direction, false);
+ }
+}
+EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
+