static struct class *bdi_class;
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+static struct dentry *bdi_debug_root;
+
+static void bdi_debug_init(void)
+{
+ bdi_debug_root = debugfs_create_dir("bdi", NULL);
+}
+
+static int bdi_debug_stats_show(struct seq_file *m, void *v)
+{
+ struct backing_dev_info *bdi = m->private;
+ long background_thresh;
+ long dirty_thresh;
+ long bdi_thresh;
+
+ get_dirty_limits(&background_thresh, &dirty_thresh, &bdi_thresh, bdi);
+
+#define K(x) ((x) << (PAGE_SHIFT - 10))
+ seq_printf(m,
+ "BdiWriteback: %8lu kB\n"
+ "BdiReclaimable: %8lu kB\n"
+ "BdiDirtyThresh: %8lu kB\n"
+ "DirtyThresh: %8lu kB\n"
+ "BackgroundThresh: %8lu kB\n",
+ (unsigned long) K(bdi_stat(bdi, BDI_WRITEBACK)),
+ (unsigned long) K(bdi_stat(bdi, BDI_RECLAIMABLE)),
+ K(bdi_thresh),
+ K(dirty_thresh),
+ K(background_thresh));
+#undef K
+
+ return 0;
+}
+
+static int bdi_debug_stats_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, bdi_debug_stats_show, inode->i_private);
+}
+
+static const struct file_operations bdi_debug_stats_fops = {
+ .open = bdi_debug_stats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void bdi_debug_register(struct backing_dev_info *bdi, const char *name)
+{
+ bdi->debug_dir = debugfs_create_dir(name, bdi_debug_root);
+ bdi->debug_stats = debugfs_create_file("stats", 0444, bdi->debug_dir,
+ bdi, &bdi_debug_stats_fops);
+}
+
+static void bdi_debug_unregister(struct backing_dev_info *bdi)
+{
+ debugfs_remove(bdi->debug_stats);
+ debugfs_remove(bdi->debug_dir);
+}
+#else
+static inline void bdi_debug_init(void)
+{
+}
+static inline void bdi_debug_register(struct backing_dev_info *bdi,
+ const char *name)
+{
+}
+static inline void bdi_debug_unregister(struct backing_dev_info *bdi)
+{
+}
+#endif
+
static ssize_t read_ahead_kb_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
BDI_SHOW(read_ahead_kb, K(bdi->ra_pages))
-BDI_SHOW(reclaimable_kb, K(bdi_stat(bdi, BDI_RECLAIMABLE)))
-BDI_SHOW(writeback_kb, K(bdi_stat(bdi, BDI_WRITEBACK)))
-
-static inline unsigned long get_dirty(struct backing_dev_info *bdi, int i)
+static ssize_t min_ratio_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
{
- unsigned long thresh[3];
-
- get_dirty_limits(&thresh[0], &thresh[1], &thresh[2], bdi);
+ struct backing_dev_info *bdi = dev_get_drvdata(dev);
+ char *end;
+ unsigned int ratio;
+ ssize_t ret = -EINVAL;
- return thresh[i];
+ ratio = simple_strtoul(buf, &end, 10);
+ if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) {
+ ret = bdi_set_min_ratio(bdi, ratio);
+ if (!ret)
+ ret = count;
+ }
+ return ret;
}
+BDI_SHOW(min_ratio, bdi->min_ratio)
-BDI_SHOW(dirty_kb, K(get_dirty(bdi, 1)))
-BDI_SHOW(bdi_dirty_kb, K(get_dirty(bdi, 2)))
-
-static ssize_t min_ratio_store(struct device *dev,
+static ssize_t max_ratio_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct backing_dev_info *bdi = dev_get_drvdata(dev);
ratio = simple_strtoul(buf, &end, 10);
if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) {
- ret = bdi_set_min_ratio(bdi, ratio);
+ ret = bdi_set_max_ratio(bdi, ratio);
if (!ret)
ret = count;
}
return ret;
}
-BDI_SHOW(min_ratio, bdi->min_ratio)
+BDI_SHOW(max_ratio, bdi->max_ratio)
#define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store)
static struct device_attribute bdi_dev_attrs[] = {
__ATTR_RW(read_ahead_kb),
- __ATTR_RO(reclaimable_kb),
- __ATTR_RO(writeback_kb),
- __ATTR_RO(dirty_kb),
- __ATTR_RO(bdi_dirty_kb),
__ATTR_RW(min_ratio),
+ __ATTR_RW(max_ratio),
__ATTR_NULL,
};
{
bdi_class = class_create(THIS_MODULE, "bdi");
bdi_class->dev_attrs = bdi_dev_attrs;
+ bdi_debug_init();
return 0;
}
-core_initcall(bdi_class_init);
+postcore_initcall(bdi_class_init);
int bdi_register(struct backing_dev_info *bdi, struct device *parent,
const char *fmt, ...)
{
- char *name;
va_list args;
int ret = 0;
struct device *dev;
va_start(args, fmt);
- name = kvasprintf(GFP_KERNEL, fmt, args);
+ dev = device_create_vargs(bdi_class, parent, MKDEV(0, 0), bdi, fmt, args);
va_end(args);
-
- if (!name)
- return -ENOMEM;
-
- dev = device_create(bdi_class, parent, MKDEV(0, 0), name);
if (IS_ERR(dev)) {
ret = PTR_ERR(dev);
goto exit;
}
bdi->dev = dev;
- dev_set_drvdata(bdi->dev, bdi);
+ bdi_debug_register(bdi, dev_name(dev));
exit:
- kfree(name);
return ret;
}
EXPORT_SYMBOL(bdi_register);
void bdi_unregister(struct backing_dev_info *bdi)
{
if (bdi->dev) {
+ bdi_debug_unregister(bdi);
device_unregister(bdi->dev);
bdi->dev = NULL;
}
bdi->dev = NULL;
bdi->min_ratio = 0;
+ bdi->max_ratio = 100;
+ bdi->max_prop_frac = PROP_FRAC_BASE;
for (i = 0; i < NR_BDI_STAT_ITEMS; i++) {
err = percpu_counter_init_irq(&bdi->bdi_stat[i], 0);