UBI: use separate mutex for volumes checking
Introduce a separate mutex which serializes volumes checking,
because we cammot really use volumes_mutex - it cases reverse
locking problems with mtd_tbl_mutex when gluebi is used -
thanks to lockdep.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 70c0b9a..6ac1339 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -703,6 +703,7 @@
goto out_free;
mutex_init(&ubi->buf_mutex);
+ mutex_init(&ubi->ckvol_mutex);
ubi->peb_buf1 = vmalloc(ubi->peb_size);
if (!ubi->peb_buf1)
goto out_free;
diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 4ec3a33..146957c 100644
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -169,17 +169,12 @@
desc->vol = vol;
desc->mode = mode;
- /*
- * To prevent simultaneous checks of the same volume we use
- * @volumes_mutex, although it is not the purpose it was introduced
- * for.
- */
- mutex_lock(&ubi->volumes_mutex);
+ mutex_lock(&ubi->ckvol_mutex);
if (!vol->checked) {
/* This is the first open - check the volume */
err = ubi_check_volume(ubi, vol_id);
if (err < 0) {
- mutex_unlock(&ubi->volumes_mutex);
+ mutex_unlock(&ubi->ckvol_mutex);
ubi_close_volume(desc);
return ERR_PTR(err);
}
@@ -190,7 +185,7 @@
}
vol->checked = 1;
}
- mutex_unlock(&ubi->volumes_mutex);
+ mutex_unlock(&ubi->ckvol_mutex);
return desc;
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 2a61712..ef22f92 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -392,6 +392,7 @@
void *peb_buf1;
void *peb_buf2;
struct mutex buf_mutex;
+ struct mutex ckvol_mutex;
#ifdef CONFIG_MTD_UBI_DEBUG
void *dbg_peb_buf;
struct mutex dbg_buf_mutex;