zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/lib/dma-debug.c b/ap/os/linux/linux-3.4.x/lib/dma-debug.c
new file mode 100644
index 0000000..13ef233
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/lib/dma-debug.c
@@ -0,0 +1,1365 @@
+/*
+ * 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/uaccess.h>
+#include <linux/export.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/ctype.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
+};
+
+typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *);
+
+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;
+static u32 nr_total_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 struct dentry *filter_dent __read_mostly;
+
+/* per-driver filter related state */
+
+#define NAME_MAX_LEN 64
+
+static char current_driver_name[NAME_MAX_LEN] __read_mostly;
+static struct device_driver *current_driver __read_mostly;
+
+static DEFINE_RWLOCK(driver_name_lock);
+
+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" };
+
+/* little merge helper - remove it after the merge window */
+#ifndef BUS_NOTIFY_UNBOUND_DRIVER
+#define BUS_NOTIFY_UNBOUND_DRIVER 0x0005
+#endif
+
+/*
+ * 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) {
+ pr_warning("Mapped at:\n");
+ print_stack_trace(&entry->stacktrace, 0);
+ }
+#endif
+}
+
+static bool driver_filter(struct device *dev)
+{
+ struct device_driver *drv;
+ unsigned long flags;
+ bool ret;
+
+ /* driver filter off */
+ if (likely(!current_driver_name[0]))
+ return true;
+
+ /* driver filter on and initialized */
+ if (current_driver && dev && dev->driver == current_driver)
+ return true;
+
+ /* driver filter on, but we can't filter on a NULL device... */
+ if (!dev)
+ return false;
+
+ if (current_driver || !current_driver_name[0])
+ return false;
+
+ /* driver filter on but not yet initialized */
+ drv = dev->driver;
+ if (!drv)
+ return false;
+
+ /* lock to protect against change of current_driver_name */
+ read_lock_irqsave(&driver_name_lock, flags);
+
+ ret = false;
+ if (drv->name &&
+ strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) {
+ current_driver = drv;
+ ret = true;
+ }
+
+ read_unlock_irqrestore(&driver_name_lock, flags);
+
+ return ret;
+}
+
+#define err_printk(dev, entry, format, arg...) do { \
+ error_count += 1; \
+ if (driver_filter(dev) && \
+ (show_all_errors || show_num_errors > 0)) { \
+ WARN(1, "%s %s: " format, \
+ dev ? dev_driver_string(dev) : "NULL", \
+ dev ? dev_name(dev) : "NULL", ## 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);
+}
+
+static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b)
+{
+ return ((a->dev_addr == b->dev_addr) &&
+ (a->dev == b->dev)) ? true : false;
+}
+
+static bool containing_match(struct dma_debug_entry *a,
+ struct dma_debug_entry *b)
+{
+ if (a->dev != b->dev)
+ return false;
+
+ if ((b->dev_addr <= a->dev_addr) &&
+ ((b->dev_addr + b->size) >= (a->dev_addr + a->size)))
+ return true;
+
+ return false;
+}
+
+/*
+ * 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,
+ match_fn match)
+{
+ struct dma_debug_entry *entry, *ret = NULL;
+ int matches = 0, match_lvl, last_lvl = 0;
+
+ list_for_each_entry(entry, &bucket->list, list) {
+ if (!match(ref, entry))
+ continue;
+
+ /*
+ * Some drivers map the same physical address multiple
+ * times. Without a hardware IOMMU this results in the
+ * same device addresses being put into the dma-debug
+ * hash multiple times too. This can result in false
+ * positives being reported. Therefore we implement a
+ * best-fit algorithm here which returns the entry from
+ * the hash which fits best to the reference value
+ * instead of the first-fit.
+ */
+ matches += 1;
+ match_lvl = 0;
+ entry->size == ref->size ? ++match_lvl : 0;
+ entry->type == ref->type ? ++match_lvl : 0;
+ entry->direction == ref->direction ? ++match_lvl : 0;
+ entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0;
+
+ if (match_lvl == 4) {
+ /* perfect-fit - return the result */
+ return entry;
+ } else if (match_lvl > last_lvl) {
+ /*
+ * We found an entry that fits better then the
+ * previous one
+ */
+ last_lvl = match_lvl;
+ ret = entry;
+ }
+ }
+
+ /*
+ * If we have multiple matches but no perfect-fit, just return
+ * NULL.
+ */
+ ret = (matches == 1) ? ret : NULL;
+
+ return ret;
+}
+
+static struct dma_debug_entry *bucket_find_exact(struct hash_bucket *bucket,
+ struct dma_debug_entry *ref)
+{
+ return __hash_bucket_find(bucket, ref, exact_match);
+}
+
+static struct dma_debug_entry *bucket_find_contain(struct hash_bucket **bucket,
+ struct dma_debug_entry *ref,
+ unsigned long *flags)
+{
+
+ unsigned int max_range = dma_get_max_seg_size(ref->dev);
+ struct dma_debug_entry *entry, index = *ref;
+ unsigned int range = 0;
+
+ while (range <= max_range) {
+ entry = __hash_bucket_find(*bucket, &index, containing_match);
+
+ if (entry)
+ return entry;
+
+ /*
+ * Nothing found, go back a hash bucket
+ */
+ put_hash_bucket(*bucket, flags);
+ range += (1 << HASH_FN_SHIFT);
+ index.dev_addr -= (1 << HASH_FN_SHIFT);
+ *bucket = get_hash_bucket(&index, flags);
+ }
+
+ 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);
+}
+
+static struct dma_debug_entry *__dma_entry_alloc(void)
+{
+ struct dma_debug_entry *entry;
+
+ entry = list_entry(free_entries.next, struct dma_debug_entry, list);
+ list_del(&entry->list);
+ memset(entry, 0, sizeof(*entry));
+
+ num_free_entries -= 1;
+ if (num_free_entries < min_free_entries)
+ min_free_entries = num_free_entries;
+
+ return entry;
+}
+
+/* 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)) {
+ pr_err("DMA-API: debugging out of memory - disabling\n");
+ global_disable = true;
+ goto out;
+ }
+
+ entry = __dma_entry_alloc();
+
+#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
+
+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);
+}
+
+int dma_debug_resize_entries(u32 num_entries)
+{
+ int i, delta, ret = 0;
+ unsigned long flags;
+ struct dma_debug_entry *entry;
+ LIST_HEAD(tmp);
+
+ spin_lock_irqsave(&free_entries_lock, flags);
+
+ if (nr_total_entries < num_entries) {
+ delta = num_entries - nr_total_entries;
+
+ spin_unlock_irqrestore(&free_entries_lock, flags);
+
+ for (i = 0; i < delta; i++) {
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ break;
+
+ list_add_tail(&entry->list, &tmp);
+ }
+
+ spin_lock_irqsave(&free_entries_lock, flags);
+
+ list_splice(&tmp, &free_entries);
+ nr_total_entries += i;
+ num_free_entries += i;
+ } else {
+ delta = nr_total_entries - num_entries;
+
+ for (i = 0; i < delta && !list_empty(&free_entries); i++) {
+ entry = __dma_entry_alloc();
+ kfree(entry);
+ }
+
+ nr_total_entries -= i;
+ }
+
+ if (nr_total_entries != num_entries)
+ ret = 1;
+
+ spin_unlock_irqrestore(&free_entries_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(dma_debug_resize_entries);
+
+/*
+ * 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;
+
+ pr_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 ssize_t filter_read(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ char buf[NAME_MAX_LEN + 1];
+ unsigned long flags;
+ int len;
+
+ if (!current_driver_name[0])
+ return 0;
+
+ /*
+ * We can't copy to userspace directly because current_driver_name can
+ * only be read under the driver_name_lock with irqs disabled. So
+ * create a temporary copy first.
+ */
+ read_lock_irqsave(&driver_name_lock, flags);
+ len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name);
+ read_unlock_irqrestore(&driver_name_lock, flags);
+
+ return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+}
+
+static ssize_t filter_write(struct file *file, const char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ char buf[NAME_MAX_LEN];
+ unsigned long flags;
+ size_t len;
+ int i;
+
+ /*
+ * We can't copy from userspace directly. Access to
+ * current_driver_name is protected with a write_lock with irqs
+ * disabled. Since copy_from_user can fault and may sleep we
+ * need to copy to temporary buffer first
+ */
+ len = min(count, (size_t)(NAME_MAX_LEN - 1));
+ if (copy_from_user(buf, userbuf, len))
+ return -EFAULT;
+
+ buf[len] = 0;
+
+ write_lock_irqsave(&driver_name_lock, flags);
+
+ /*
+ * Now handle the string we got from userspace very carefully.
+ * The rules are:
+ * - only use the first token we got
+ * - token delimiter is everything looking like a space
+ * character (' ', '\n', '\t' ...)
+ *
+ */
+ if (!isalnum(buf[0])) {
+ /*
+ * If the first character userspace gave us is not
+ * alphanumerical then assume the filter should be
+ * switched off.
+ */
+ if (current_driver_name[0])
+ pr_info("DMA-API: switching off dma-debug driver filter\n");
+ current_driver_name[0] = 0;
+ current_driver = NULL;
+ goto out_unlock;
+ }
+
+ /*
+ * Now parse out the first token and use it as the name for the
+ * driver to filter for.
+ */
+ for (i = 0; i < NAME_MAX_LEN - 1; ++i) {
+ current_driver_name[i] = buf[i];
+ if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0)
+ break;
+ }
+ current_driver_name[i] = 0;
+ current_driver = NULL;
+
+ pr_info("DMA-API: enable driver filter for driver [%s]\n",
+ current_driver_name);
+
+out_unlock:
+ write_unlock_irqrestore(&driver_name_lock, flags);
+
+ return count;
+}
+
+static const struct file_operations filter_fops = {
+ .read = filter_read,
+ .write = filter_write,
+ .llseek = default_llseek,
+};
+
+static int dma_debug_fs_init(void)
+{
+ dma_debug_dent = debugfs_create_dir("dma-api", NULL);
+ if (!dma_debug_dent) {
+ pr_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;
+
+ filter_dent = debugfs_create_file("driver_filter", 0644,
+ dma_debug_dent, NULL, &filter_fops);
+ if (!filter_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 **out_entry)
+{
+ struct dma_debug_entry *entry;
+ unsigned long flags;
+ int count = 0, i;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < HASH_SIZE; ++i) {
+ spin_lock(&dma_entry_hash[i].lock);
+ list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
+ if (entry->dev == dev) {
+ count += 1;
+ *out_entry = entry;
+ }
+ }
+ spin_unlock(&dma_entry_hash[i].lock);
+ }
+
+ local_irq_restore(flags);
+
+ return count;
+}
+
+static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data)
+{
+ struct device *dev = data;
+ struct dma_debug_entry *uninitialized_var(entry);
+ int count;
+
+ if (global_disable)
+ return 0;
+
+ switch (action) {
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ count = device_dma_allocations(dev, &entry);
+ if (count == 0)
+ break;
+ err_printk(dev, entry, "DMA-API: device driver has pending "
+ "DMA allocations while released from device "
+ "[count=%d]\n"
+ "One of leaked entries details: "
+ "[device address=0x%016llx] [size=%llu bytes] "
+ "[mapped with %s] [mapped as %s]\n",
+ count, entry->dev_addr, entry->size,
+ dir2name[entry->direction], type2name[entry->type]);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+void dma_debug_add_bus(struct bus_type *bus)
+{
+ struct notifier_block *nb;
+
+ if (global_disable)
+ return;
+
+ nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
+ if (nb == NULL) {
+ pr_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);
+ spin_lock_init(&dma_entry_hash[i].lock);
+ }
+
+ if (dma_debug_fs_init() != 0) {
+ pr_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) {
+ pr_err("DMA-API: debugging out of memory error - disabled\n");
+ global_disable = true;
+
+ return;
+ }
+
+ nr_total_entries = num_free_entries;
+
+ pr_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) {
+ pr_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 = bucket_find_exact(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=0x%016llx] "
+ "[cpu free address=0x%016llx]",
+ ref->dev_addr, ref->size,
+ (unsigned long long)entry->paddr,
+ (unsigned long long)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, unsigned long len, void *start, void *end)
+{
+ unsigned long a1 = (unsigned long)addr;
+ unsigned long b1 = a1 + len;
+ unsigned long a2 = (unsigned long)start;
+ unsigned long b2 = (unsigned long)end;
+
+ return !(b1 <= a2 || a1 >= b2);
+}
+
+static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len)
+{
+ if (overlap(addr, len, _text, _etext) ||
+ overlap(addr, len, __start_rodata, __end_rodata))
+ err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len);
+}
+
+static void check_sync(struct device *dev,
+ struct dma_debug_entry *ref,
+ bool to_cpu)
+{
+ struct dma_debug_entry *entry;
+ struct hash_bucket *bucket;
+ unsigned long flags;
+
+ bucket = get_hash_bucket(ref, &flags);
+
+ entry = bucket_find_contain(&bucket, ref, &flags);
+
+ 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)ref->dev_addr, ref->size);
+ goto out;
+ }
+
+ if (ref->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+size=%llu]\n",
+ entry->dev_addr, entry->size,
+ ref->size);
+ }
+
+ if (entry->direction == DMA_BIDIRECTIONAL)
+ goto out;
+
+ if (ref->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)ref->dev_addr, entry->size,
+ dir2name[entry->direction],
+ dir2name[ref->direction]);
+ }
+
+ if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
+ !(ref->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)ref->dev_addr, entry->size,
+ dir2name[entry->direction],
+ dir2name[ref->direction]);
+
+ if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
+ !(ref->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)ref->dev_addr, entry->size,
+ dir2name[entry->direction],
+ dir2name[ref->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 = 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 = sg_dma_len(s);
+ entry->dev_addr = sg_dma_address(s);
+ 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), sg_dma_len(s));
+ }
+
+ add_dma_entry(entry);
+ }
+}
+EXPORT_SYMBOL(debug_dma_map_sg);
+
+static int get_nr_mapped_entries(struct device *dev,
+ struct dma_debug_entry *ref)
+{
+ struct dma_debug_entry *entry;
+ struct hash_bucket *bucket;
+ unsigned long flags;
+ int mapped_ents;
+
+ bucket = get_hash_bucket(ref, &flags);
+ entry = bucket_find_exact(bucket, ref);
+ mapped_ents = 0;
+
+ if (entry)
+ mapped_ents = entry->sg_mapped_ents;
+ put_hash_bucket(bucket, &flags);
+
+ return mapped_ents;
+}
+
+void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, int dir)
+{
+ struct scatterlist *s;
+ int mapped_ents = 0, i;
+
+ 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 = sg_dma_address(s),
+ .size = sg_dma_len(s),
+ .direction = dir,
+ .sg_call_ents = nelems,
+ };
+
+ if (mapped_ents && i >= mapped_ents)
+ break;
+
+ if (!i)
+ mapped_ents = get_nr_mapped_entries(dev, &ref);
+
+ 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)
+{
+ struct dma_debug_entry ref;
+
+ if (unlikely(global_disable))
+ return;
+
+ ref.type = dma_debug_single;
+ ref.dev = dev;
+ ref.dev_addr = dma_handle;
+ ref.size = size;
+ ref.direction = direction;
+ ref.sg_call_ents = 0;
+
+ check_sync(dev, &ref, 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)
+{
+ struct dma_debug_entry ref;
+
+ if (unlikely(global_disable))
+ return;
+
+ ref.type = dma_debug_single;
+ ref.dev = dev;
+ ref.dev_addr = dma_handle;
+ ref.size = size;
+ ref.direction = direction;
+ ref.sg_call_ents = 0;
+
+ check_sync(dev, &ref, 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)
+{
+ struct dma_debug_entry ref;
+
+ if (unlikely(global_disable))
+ return;
+
+ ref.type = dma_debug_single;
+ ref.dev = dev;
+ ref.dev_addr = dma_handle;
+ ref.size = offset + size;
+ ref.direction = direction;
+ ref.sg_call_ents = 0;
+
+ check_sync(dev, &ref, 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)
+{
+ struct dma_debug_entry ref;
+
+ if (unlikely(global_disable))
+ return;
+
+ ref.type = dma_debug_single;
+ ref.dev = dev;
+ ref.dev_addr = dma_handle;
+ ref.size = offset + size;
+ ref.direction = direction;
+ ref.sg_call_ents = 0;
+
+ check_sync(dev, &ref, 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 mapped_ents = 0, i;
+
+ if (unlikely(global_disable))
+ return;
+
+ for_each_sg(sg, s, nelems, i) {
+
+ struct dma_debug_entry ref = {
+ .type = dma_debug_sg,
+ .dev = dev,
+ .paddr = sg_phys(s),
+ .dev_addr = sg_dma_address(s),
+ .size = sg_dma_len(s),
+ .direction = direction,
+ .sg_call_ents = nelems,
+ };
+
+ if (!i)
+ mapped_ents = get_nr_mapped_entries(dev, &ref);
+
+ if (i >= mapped_ents)
+ break;
+
+ check_sync(dev, &ref, 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 mapped_ents = 0, i;
+
+ if (unlikely(global_disable))
+ return;
+
+ for_each_sg(sg, s, nelems, i) {
+
+ struct dma_debug_entry ref = {
+ .type = dma_debug_sg,
+ .dev = dev,
+ .paddr = sg_phys(s),
+ .dev_addr = sg_dma_address(s),
+ .size = sg_dma_len(s),
+ .direction = direction,
+ .sg_call_ents = nelems,
+ };
+ if (!i)
+ mapped_ents = get_nr_mapped_entries(dev, &ref);
+
+ if (i >= mapped_ents)
+ break;
+
+ check_sync(dev, &ref, false);
+ }
+}
+EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
+
+static int __init dma_debug_driver_setup(char *str)
+{
+ int i;
+
+ for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) {
+ current_driver_name[i] = *str;
+ if (*str == 0)
+ break;
+ }
+
+ if (current_driver_name[0])
+ pr_info("DMA-API: enable driver filter for driver [%s]\n",
+ current_driver_name);
+
+
+ return 1;
+}
+__setup("dma_debug_driver=", dma_debug_driver_setup);