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authorHans J. Koch <hjk@linutronix.de>2008-09-19 01:53:18 +0400
committerGreg Kroah-Hartman <gregkh@suse.de>2008-10-16 20:24:53 +0400
commite2b39df119712ea5184562a6a14696a5cea8ef18 (patch)
treeb855a7b4e8893df122c96c69976d37a1a563492e /drivers/uio
parent99178b036c97293a65004ff5ec5cff9f833aaecd (diff)
downloadlinux-e2b39df119712ea5184562a6a14696a5cea8ef18.tar.xz
UIO: Add alignment warnings for uio-mem
This patch adds an "offset" attribute for UIO mappings. It shows the difference between the actual start address of the memory and the start address of the page. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/uio')
-rw-r--r--drivers/uio/uio.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 9ac22c7c3854..557e73ef5884 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -67,6 +67,11 @@ static ssize_t map_size_show(struct uio_mem *mem, char *buf)
return sprintf(buf, "0x%lx\n", mem->size);
}
+static ssize_t map_offset_show(struct uio_mem *mem, char *buf)
+{
+ return sprintf(buf, "0x%lx\n", mem->addr & ~PAGE_MASK);
+}
+
struct uio_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct uio_mem *, char *);
@@ -77,10 +82,13 @@ static struct uio_sysfs_entry addr_attribute =
__ATTR(addr, S_IRUGO, map_addr_show, NULL);
static struct uio_sysfs_entry size_attribute =
__ATTR(size, S_IRUGO, map_size_show, NULL);
+static struct uio_sysfs_entry offset_attribute =
+ __ATTR(offset, S_IRUGO, map_offset_show, NULL);
static struct attribute *attrs[] = {
&addr_attribute.attr,
&size_attribute.attr,
+ &offset_attribute.attr,
NULL, /* need to NULL terminate the list of attributes */
};