UBI: add UBI devices reference counting
This is one more step on the way to "removable" UBI devices. It
adds reference counting for UBI devices. Every time a volume on
this device is opened - the device's refcount is increased. It
is also increased if someone is reading any sysfs file of this
UBI device or of one of its volumes.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index c94f475..85297cd 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -339,6 +339,7 @@
{
int err, pnum, vol_id = vol->vol_id;
+ ubi_assert(ubi->ref_count > 0);
ubi_assert(vol->ref_count > 0);
if (ubi->ro_mode)
@@ -389,6 +390,7 @@
struct ubi_vid_hdr *vid_hdr;
uint32_t uninitialized_var(crc);
+ ubi_assert(ubi->ref_count > 0);
ubi_assert(vol->ref_count > 0);
err = leb_read_lock(ubi, vol_id, lnum);
@@ -614,6 +616,7 @@
int err, pnum, tries = 0, vol_id = vol->vol_id;
struct ubi_vid_hdr *vid_hdr;
+ ubi_assert(ubi->ref_count > 0);
ubi_assert(vol->ref_count > 0);
if (ubi->ro_mode)
@@ -749,6 +752,7 @@
struct ubi_vid_hdr *vid_hdr;
uint32_t crc;
+ ubi_assert(ubi->ref_count > 0);
ubi_assert(vol->ref_count > 0);
if (ubi->ro_mode)
@@ -865,6 +869,7 @@
struct ubi_vid_hdr *vid_hdr;
uint32_t crc;
+ ubi_assert(ubi->ref_count > 0);
ubi_assert(vol->ref_count > 0);
if (ubi->ro_mode)