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-rw-r--r--lib/bitmap.c33
1 files changed, 20 insertions, 13 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 0d5c2ece0bcb..8ebe508580ea 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -527,33 +527,39 @@ static int bitmap_print_to_buf(bool list, char *buf, const unsigned long *maskp,
* cpumap_print_to_pagebuf() or directly by drivers to export hexadecimal
* bitmask and decimal list to userspace by sysfs ABI.
* Drivers might be using a normal attribute for this kind of ABIs. A
- * normal attribute typically has show entry as below:
- * static ssize_t example_attribute_show(struct device *dev,
+ * normal attribute typically has show entry as below::
+ *
+ * static ssize_t example_attribute_show(struct device *dev,
* struct device_attribute *attr, char *buf)
- * {
+ * {
* ...
* return bitmap_print_to_pagebuf(true, buf, &mask, nr_trig_max);
- * }
+ * }
+ *
* show entry of attribute has no offset and count parameters and this
* means the file is limited to one page only.
* bitmap_print_to_pagebuf() API works terribly well for this kind of
- * normal attribute with buf parameter and without offset, count:
- * bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
+ * normal attribute with buf parameter and without offset, count::
+ *
+ * bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
* int nmaskbits)
- * {
- * }
+ * {
+ * }
+ *
* The problem is once we have a large bitmap, we have a chance to get a
* bitmask or list more than one page. Especially for list, it could be
* as complex as 0,3,5,7,9,... We have no simple way to know it exact size.
* It turns out bin_attribute is a way to break this limit. bin_attribute
- * has show entry as below:
- * static ssize_t
- * example_bin_attribute_show(struct file *filp, struct kobject *kobj,
+ * has show entry as below::
+ *
+ * static ssize_t
+ * example_bin_attribute_show(struct file *filp, struct kobject *kobj,
* struct bin_attribute *attr, char *buf,
* loff_t offset, size_t count)
- * {
+ * {
* ...
- * }
+ * }
+ *
* With the new offset and count parameters, this makes sysfs ABI be able
* to support file size more than one page. For example, offset could be
* >= 4096.
@@ -577,6 +583,7 @@ static int bitmap_print_to_buf(bool list, char *buf, const unsigned long *maskp,
* This function is not a replacement for sprintf() or bitmap_print_to_pagebuf().
* It is intended to workaround sysfs limitations discussed above and should be
* used carefully in general case for the following reasons:
+ *
* - Time complexity is O(nbits^2/count), comparing to O(nbits) for snprintf().
* - Memory complexity is O(nbits), comparing to O(1) for snprintf().
* - @off and @count are NOT offset and number of bits to print.