Btrfs: fix key checks and advance in the search ioctl
The search ioctl was working well for finding tree roots, but using it for
generic searches requires a few changes to how the keys are advanced.
This treats the search control min fields for objectid, type and offset
more like a key, where we drop the offset to zero once we bump the type,
etc.
The downside of this is that we are changing the min_type and min_offset
fields during the search, and so the ioctl caller needs extra checks to make sure
the keys in the result are the ones it wanted.
This also changes key_in_sk to use btrfs_comp_cpu_keys, just to make
things more readable.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 4329610..291aa51f 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -914,17 +914,23 @@
static noinline int key_in_sk(struct btrfs_key *key,
struct btrfs_ioctl_search_key *sk)
{
- if (key->objectid < sk->min_objectid)
+ struct btrfs_key test;
+ int ret;
+
+ test.objectid = sk->min_objectid;
+ test.type = sk->min_type;
+ test.offset = sk->min_offset;
+
+ ret = btrfs_comp_cpu_keys(key, &test);
+ if (ret < 0)
return 0;
- if (key->offset < sk->min_offset)
- return 0;
- if (key->type < sk->min_type)
- return 0;
- if (key->objectid > sk->max_objectid)
- return 0;
- if (key->type > sk->max_type)
- return 0;
- if (key->offset > sk->max_offset)
+
+ test.objectid = sk->max_objectid;
+ test.type = sk->max_type;
+ test.offset = sk->max_offset;
+
+ ret = btrfs_comp_cpu_keys(key, &test);
+ if (ret > 0)
return 0;
return 1;
}
@@ -998,13 +1004,18 @@
break;
}
advance_key:
- if (key->offset < (u64)-1)
- key->offset++;
- else if (key->type < (u8)-1)
- key->type++;
- else if (key->objectid < (u64)-1)
- key->objectid++;
ret = 0;
+ if (key->offset < (u64)-1 && key->offset < sk->max_offset)
+ key->offset++;
+ else if (key->type < (u8)-1 && key->type < sk->max_type) {
+ key->offset = 0;
+ key->type++;
+ } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
+ key->offset = 0;
+ key->type = 0;
+ key->objectid++;
+ } else
+ ret = 1;
overflow:
*num_found += found;
return ret;