udf: Move handling of uniqueID into a helper function and protect it by a s_alloc_mutex
uniqueID handling has been duplicated in three places. Move it into a common
helper. Since we modify an LVID buffer with uniqueID update, we take
sbi->s_alloc_mutex to protect agaist other modifications of the structure.
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/udf/super.c b/fs/udf/super.c
index f99ff5d..948e1ac 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1823,6 +1823,33 @@
sbi->s_lvid_dirty = 0;
}
+u64 lvid_get_unique_id(struct super_block *sb)
+{
+ struct buffer_head *bh;
+ struct udf_sb_info *sbi = UDF_SB(sb);
+ struct logicalVolIntegrityDesc *lvid;
+ struct logicalVolHeaderDesc *lvhd;
+ u64 uniqueID;
+ u64 ret;
+
+ bh = sbi->s_lvid_bh;
+ if (!bh)
+ return 0;
+
+ lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
+ lvhd = (struct logicalVolHeaderDesc *)lvid->logicalVolContentsUse;
+
+ mutex_lock(&sbi->s_alloc_mutex);
+ ret = uniqueID = le64_to_cpu(lvhd->uniqueID);
+ if (!(++uniqueID & 0xFFFFFFFF))
+ uniqueID += 16;
+ lvhd->uniqueID = cpu_to_le64(uniqueID);
+ mutex_unlock(&sbi->s_alloc_mutex);
+ mark_buffer_dirty(bh);
+
+ return ret;
+}
+
static void udf_sb_free_bitmap(struct udf_bitmap *bitmap)
{
int i;