On 10/8/18 8:30 PM, Qu Wenruo wrote:
Add such check at check_dev_item(), since at that timing we're also
iterating dev extents for dev item accounting.
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
LGTM.
Reviewed-by: Su Yue <suy.fnst@xxxxxxxxxxxxxx>
---
check/mode-lowmem.c | 34 ++++++++++++++++++++++++++++++++--
1 file changed, 32 insertions(+), 2 deletions(-)
diff --git a/check/mode-lowmem.c b/check/mode-lowmem.c
index 1bce44f5658a..07c03cad77af 100644
--- a/check/mode-lowmem.c
+++ b/check/mode-lowmem.c
@@ -4065,6 +4065,8 @@ static int check_dev_item(struct btrfs_fs_info *fs_info,
u64 dev_id;
u64 used;
u64 total = 0;
+ u64 prev_devid = 0;
+ u64 prev_dev_ext_end = 0;
int ret;
dev_item = btrfs_item_ptr(eb, slot, struct btrfs_dev_item);
@@ -4086,8 +4088,16 @@ static int check_dev_item(struct btrfs_fs_info *fs_info,
return REFERENCER_MISSING;
}
- /* Iterate dev_extents to calculate the used space of a device */
+ /*
+ * Iterate dev_extents to calculate the used space of a device
+ *
+ * Also make sure no dev extents overlap and end beyond device boundary
+ */
while (1) {
+ u64 devid;
+ u64 physical_offset;
+ u64 physical_len;
+
if (path.slots[0] >= btrfs_header_nritems(path.nodes[0]))
goto next;
@@ -4099,7 +4109,27 @@ static int check_dev_item(struct btrfs_fs_info *fs_info,
ptr = btrfs_item_ptr(path.nodes[0], path.slots[0],
struct btrfs_dev_extent);
- total += btrfs_dev_extent_length(path.nodes[0], ptr);
+ devid = key.objectid;
+ physical_offset = key.offset;
+ physical_len = btrfs_dev_extent_length(path.nodes[0], ptr);
+
+ if (prev_devid == devid && physical_offset < prev_dev_ext_end) {
+ error(
+"dev extent devid %llu offset %llu len %llu overlap with previous dev extent end %llu",
+ devid, physical_offset, physical_len,
+ prev_dev_ext_end);
+ return ACCOUNTING_MISMATCH;
+ }
+ if (physical_offset + physical_len > total_bytes) {
+ error(
+"dev extent devid %llu offset %llu len %llu is beyond device boundary %llu",
+ devid, physical_offset, physical_len,
+ total_bytes);
+ return ACCOUNTING_MISMATCH;
+ }
+ prev_devid = devid;
+ prev_dev_ext_end = physical_offset + physical_len;
+ total += physical_len;
next:
ret = btrfs_next_item(dev_root, &path);
if (ret)
