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-rw-r--r--lib/Kconfig12
-rw-r--r--lib/Kconfig.debug86
-rw-r--r--lib/Makefile9
-rw-r--r--lib/dma-debug.c955
-rw-r--r--lib/dynamic_debug.c769
-rw-r--r--lib/dynamic_printk.c414
-rw-r--r--lib/kernel_lock.c2
-rw-r--r--lib/kobject.c2
-rw-r--r--lib/kobject_uevent.c12
-rw-r--r--lib/lmb.c42
-rw-r--r--lib/nlattr.c502
-rw-r--r--lib/rbtree.c14
-rw-r--r--lib/swiotlb.c88
13 files changed, 2369 insertions, 538 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 206f36a9efb..8ade0a7a91e 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -153,12 +153,6 @@ config TEXTSEARCH_BM
config TEXTSEARCH_FSM
tristate
-#
-# plist support is select#ed if needed
-#
-config PLIST
- boolean
-
config HAS_IOMEM
boolean
depends on !NO_IOMEM
@@ -191,4 +185,10 @@ config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
depends on EXPERIMENTAL && BROKEN
+#
+# Netlink attribute parsing support is select'ed if needed
+#
+config NLATTR
+ bool
+
endmenu
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index a0879b2e8b6..9638d99644a 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -402,7 +402,7 @@ config LOCKDEP
bool
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
select STACKTRACE
- select FRAME_POINTER if !MIPS && !PPC
+ select FRAME_POINTER if !X86 && !MIPS && !PPC && !ARM_UNWIND
select KALLSYMS
select KALLSYMS_ALL
@@ -796,6 +796,7 @@ config SYSCTL_SYSCALL_CHECK
to properly maintain and use. This enables checks that help
you to keep things correct.
+source mm/Kconfig.debug
source kernel/trace/Kconfig
config PROVIDE_OHCI1394_DMA_INIT
@@ -847,60 +848,81 @@ config BUILD_DOCSRC
Say N if you are unsure.
-config DYNAMIC_PRINTK_DEBUG
- bool "Enable dynamic printk() call support"
+config DYNAMIC_DEBUG
+ bool "Enable dynamic printk() support"
default n
depends on PRINTK
+ depends on DEBUG_FS
select PRINTK_DEBUG
help
Compiles debug level messages into the kernel, which would not
otherwise be available at runtime. These messages can then be
- enabled/disabled on a per module basis. This mechanism implicitly
- enables all pr_debug() and dev_dbg() calls. The impact of this
- compile option is a larger kernel text size of about 2%.
+ enabled/disabled based on various levels of scope - per source file,
+ function, module, format string, and line number. This mechanism
+ implicitly enables all pr_debug() and dev_dbg() calls. The impact of
+ this compile option is a larger kernel text size of about 2%.
Usage:
- Dynamic debugging is controlled by the debugfs file,
- dynamic_printk/modules. This file contains a list of the modules that
- can be enabled. The format of the file is the module name, followed
- by a set of flags that can be enabled. The first flag is always the
- 'enabled' flag. For example:
+ Dynamic debugging is controlled via the 'dynamic_debug/ddebug' file,
+ which is contained in the 'debugfs' filesystem. Thus, the debugfs
+ filesystem must first be mounted before making use of this feature.
+ We refer the control file as: <debugfs>/dynamic_debug/ddebug. This
+ file contains a list of the debug statements that can be enabled. The
+ format for each line of the file is:
- <module_name> <enabled=0/1>
- .
- .
- .
+ filename:lineno [module]function flags format
- <module_name> : Name of the module in which the debug call resides
- <enabled=0/1> : whether the messages are enabled or not
+ filename : source file of the debug statement
+ lineno : line number of the debug statement
+ module : module that contains the debug statement
+ function : function that contains the debug statement
+ flags : 'p' means the line is turned 'on' for printing
+ format : the format used for the debug statement
From a live system:
- snd_hda_intel enabled=0
- fixup enabled=0
- driver enabled=0
-
- Enable a module:
+ nullarbor:~ # cat <debugfs>/dynamic_debug/ddebug
+ # filename:lineno [module]function flags format
+ fs/aio.c:222 [aio]__put_ioctx - "__put_ioctx:\040freeing\040%p\012"
+ fs/aio.c:248 [aio]ioctx_alloc - "ENOMEM:\040nr_events\040too\040high\012"
+ fs/aio.c:1770 [aio]sys_io_cancel - "calling\040cancel\012"
- $echo "set enabled=1 <module_name>" > dynamic_printk/modules
+ Example usage:
- Disable a module:
+ // enable the message at line 1603 of file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
+ <debugfs>/dynamic_debug/ddebug
- $echo "set enabled=0 <module_name>" > dynamic_printk/modules
+ // enable all the messages in file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c +p' >
+ <debugfs>/dynamic_debug/ddebug
- Enable all modules:
+ // enable all the messages in the NFS server module
+ nullarbor:~ # echo -n 'module nfsd +p' >
+ <debugfs>/dynamic_debug/ddebug
- $echo "set enabled=1 all" > dynamic_printk/modules
+ // enable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process +p' >
+ <debugfs>/dynamic_debug/ddebug
- Disable all modules:
+ // disable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process -p' >
+ <debugfs>/dynamic_debug/ddebug
- $echo "set enabled=0 all" > dynamic_printk/modules
+ See Documentation/dynamic-debug-howto.txt for additional information.
- Finally, passing "dynamic_printk" at the command line enables
- debugging for all modules. This mode can be turned off via the above
- disable command.
+config DMA_API_DEBUG
+ bool "Enable debugging of DMA-API usage"
+ depends on HAVE_DMA_API_DEBUG
+ help
+ Enable this option to debug the use of the DMA API by device drivers.
+ With this option you will be able to detect common bugs in device
+ drivers like double-freeing of DMA mappings or freeing mappings that
+ were never allocated.
+ This option causes a performance degredation. Use only if you want
+ to debug device drivers. If unsure, say N.
source "samples/Kconfig"
diff --git a/lib/Makefile b/lib/Makefile
index 790de7c25d0..d6edd6753f4 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -12,7 +12,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
idr.o int_sqrt.o extable.o prio_tree.o \
sha1.o irq_regs.o reciprocal_div.o argv_split.o \
proportions.o prio_heap.o ratelimit.o show_mem.o \
- is_single_threaded.o decompress.o
+ is_single_threaded.o plist.o decompress.o
lib-$(CONFIG_MMU) += ioremap.o
lib-$(CONFIG_SMP) += cpumask.o
@@ -41,7 +41,6 @@ lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
lib-$(CONFIG_GENERIC_FIND_LAST_BIT) += find_last_bit.o
obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
-obj-$(CONFIG_PLIST) += plist.o
obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o
obj-$(CONFIG_DEBUG_LIST) += list_debug.o
obj-$(CONFIG_DEBUG_OBJECTS) += debugobjects.o
@@ -87,7 +86,11 @@ obj-$(CONFIG_HAVE_LMB) += lmb.o
obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o
-obj-$(CONFIG_DYNAMIC_PRINTK_DEBUG) += dynamic_printk.o
+obj-$(CONFIG_DYNAMIC_DEBUG) += dynamic_debug.o
+
+obj-$(CONFIG_NLATTR) += nlattr.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 00000000000..d3da7edc034
--- /dev/null
+++ b/lib/dma-debug.c
@@ -0,0 +1,955 @@
+/*
+ * 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)) {
+ err_printk(ref->dev, NULL, "DMA-API: device driver tries "
+ "to free an invalid DMA memory address\n");
+ 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",
+ (unsigned long long)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",
+ (unsigned long long)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",
+ (unsigned long long)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",
+ (unsigned long long)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)
+ entry->type = dma_debug_single;
+
+ if (!PageHighMem(page)) {
+ void *addr = ((char *)page_address(page)) + offset;
+ 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;
+
+ if (!PageHighMem(sg_page(s))) {
+ 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,<