#include <linux/dma-debug.h>
#include <linux/spinlock.h>
#include <linux/debugfs.h>
+#include <linux/uaccess.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>
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
{
#ifdef CONFIG_STACKTRACE
if (entry) {
- printk(KERN_WARNING "Mapped at:\n");
+ pr_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; \
+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 = get_driver(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);
+ put_driver(drv);
+
+ 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);
/*
*/
matches += 1;
match_lvl = 0;
- entry->size == ref->size ? ++match_lvl : match_lvl;
- entry->type == ref->type ? ++match_lvl : match_lvl;
- entry->direction == ref->direction ? ++match_lvl : match_lvl;
+ 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 == 3) {
+ if (match_lvl == 4) {
/* perfect-fit - return the result */
return entry;
} else if (match_lvl > last_lvl) {
spin_lock_irqsave(&free_entries_lock, flags);
if (list_empty(&free_entries)) {
- printk(KERN_ERR "DMA-API: debugging out of memory "
- "- disabling\n");
+ pr_err("DMA-API: debugging out of memory - disabling\n");
global_disable = true;
goto out;
}
num_free_entries = num_entries;
min_free_entries = num_entries;
- printk(KERN_INFO "DMA-API: preallocated %d debug entries\n",
- num_entries);
+ pr_info("DMA-API: preallocated %d debug entries\n", num_entries);
return 0;
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; ++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;
+}
+
+const struct file_operations filter_fops = {
+ .read = filter_read,
+ .write = filter_write,
+};
+
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");
+ pr_err("DMA-API: can not create debugfs directory\n");
return -ENOMEM;
}
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:
return -ENOMEM;
}
+static int device_dma_allocations(struct device *dev)
+{
+ 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;
+ }
+ 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;
+ int count;
+
+
+ switch (action) {
+ case BUS_NOTIFY_UNBOUND_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)
{
- /* FIXME: register notifier */
+ struct notifier_block *nb;
+
+ 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);
}
/*
for (i = 0; i < HASH_SIZE; ++i) {
INIT_LIST_HEAD(&dma_entry_hash[i].list);
- dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
+ spin_lock_init(&dma_entry_hash[i].lock);
}
if (dma_debug_fs_init() != 0) {
- printk(KERN_ERR "DMA-API: error creating debugfs entries "
- "- disabling\n");
+ pr_err("DMA-API: error creating debugfs entries - disabling\n");
global_disable = true;
return;
num_entries = req_entries;
if (prealloc_memory(num_entries) != 0) {
- printk(KERN_ERR "DMA-API: debugging out of memory error "
- "- disabled\n");
+ pr_err("DMA-API: debugging out of memory error - disabled\n");
global_disable = true;
return;
nr_total_entries = num_free_entries;
- printk(KERN_INFO "DMA-API: debugging enabled by kernel config\n");
+ pr_info("DMA-API: debugging enabled by kernel config\n");
}
static __init int dma_debug_cmdline(char *str)
return -EINVAL;
if (strncmp(str, "off", 3) == 0) {
- printk(KERN_INFO "DMA-API: debugging disabled on kernel "
- "command line\n");
+ pr_info("DMA-API: debugging disabled on kernel command line\n");
global_disable = true;
}
"stack [addr=%p]\n", addr);
}
-static inline bool overlap(void *addr, u64 size, void *start, void *end)
+static inline bool overlap(void *addr, unsigned long len, void *start, void *end)
{
- void *addr2 = (char *)addr + size;
+ unsigned long a1 = (unsigned long)addr;
+ unsigned long b1 = a1 + len;
+ unsigned long a2 = (unsigned long)start;
+ unsigned long b2 = (unsigned long)end;
- return ((addr >= start && addr < end) ||
- (addr2 >= start && addr2 < end) ||
- ((addr < start) && (addr2 >= end)));
+ return !(b1 <= a2 || a1 >= b2);
}
-static void check_for_illegal_area(struct device *dev, void *addr, u64 size)
+static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len)
{
- 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);
+ 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, dma_addr_t addr,
- u64 size, u64 offset, int direction, bool to_cpu)
+static void check_sync(struct device *dev,
+ struct dma_debug_entry *ref,
+ 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);
+ bucket = get_hash_bucket(ref, &flags);
- entry = hash_bucket_find(bucket, &ref);
+ 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);
+ (unsigned long long)ref->dev_addr, ref->size);
goto out;
}
- if ((offset + size) > entry->size) {
+ 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=%llu] "
- "[sync size=%llu]\n", entry->dev_addr, entry->size,
- offset, size);
+ "[allocation size=%llu bytes] "
+ "[sync offset+size=%llu]\n",
+ entry->dev_addr, entry->size,
+ ref->size);
}
- if (direction != entry->direction) {
+ 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)addr, entry->size,
+ (unsigned long long)ref->dev_addr, entry->size,
dir2name[entry->direction],
- dir2name[direction]);
+ dir2name[ref->direction]);
}
if (entry->direction == DMA_BIDIRECTIONAL)
goto out;
if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) &&
- !(direction == DMA_TO_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)addr, entry->size,
+ (unsigned long long)ref->dev_addr, entry->size,
dir2name[entry->direction],
- dir2name[direction]);
+ dir2name[ref->direction]);
if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) &&
- !(direction == DMA_FROM_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)addr, entry->size,
+ (unsigned long long)ref->dev_addr, entry->size,
dir2name[entry->direction],
- dir2name[direction]);
+ dir2name[ref->direction]);
out:
put_hash_bucket(bucket, &flags);
entry->type = dma_debug_single;
if (!PageHighMem(page)) {
- void *addr = ((char *)page_address(page)) + offset;
+ void *addr = page_address(page) + offset;
+
check_for_stack(dev, addr);
check_for_illegal_area(dev, addr, size);
}
entry->type = dma_debug_sg;
entry->dev = dev;
entry->paddr = sg_phys(s);
- entry->size = s->length;
- entry->dev_addr = s->dma_address;
+ 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), s->length);
+ 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 = hash_bucket_find(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 dma_debug_entry *entry;
struct scatterlist *s;
int mapped_ents = 0, i;
- unsigned long flags;
if (unlikely(global_disable))
return;
.type = dma_debug_sg,
.dev = dev,
.paddr = sg_phys(s),
- .dev_addr = s->dma_address,
- .size = s->length,
+ .dev_addr = sg_dma_address(s),
+ .size = sg_dma_len(s),
.direction = dir,
- .sg_call_ents = 0,
+ .sg_call_ents = nelems,
};
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);
- }
+ if (!i)
+ mapped_ents = get_nr_mapped_entries(dev, &ref);
check_unmap(&ref);
}
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;
- check_sync(dev, dma_handle, size, 0, direction, true);
+ 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);
dma_addr_t dma_handle, size_t size,
int direction)
{
+ struct dma_debug_entry ref;
+
if (unlikely(global_disable))
return;
- check_sync(dev, dma_handle, size, 0, direction, false);
+ 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);
unsigned long offset, size_t size,
int direction)
{
+ struct dma_debug_entry ref;
+
if (unlikely(global_disable))
return;
- check_sync(dev, dma_handle, size, offset, direction, true);
+ 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);
unsigned long offset,
size_t size, int direction)
{
+ struct dma_debug_entry ref;
+
if (unlikely(global_disable))
return;
- check_sync(dev, dma_handle, size, offset, direction, false);
+ 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);
int nelems, int direction)
{
struct scatterlist *s;
- int i;
+ int mapped_ents = 0, 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);
+
+ 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);
int nelems, int direction)
{
struct scatterlist *s;
- int i;
+ int mapped_ents = 0, 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);
+
+ 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);
Code Review / linux-2.6.git / blobdiff