Btrfs: Handle data checksumming on bios that span multiple ordered extents
Data checksumming is done right before the bio is sent down the IO stack,
which means a single bio might span more than one ordered extent. In
this case, the checksumming data is split between two ordered extents.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 98f491d..1794efd 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -39,7 +39,11 @@
struct btrfs_ordered_sum {
u64 file_offset;
- u64 len;
+ /*
+ * this is the length in bytes covered by the sums array below.
+ * But, the sums array may not be contiguous in the file.
+ */
+ unsigned long len;
struct list_head list;
/* last field is a variable length array of btrfs_sector_sums */
struct btrfs_sector_sum sums;
@@ -95,6 +99,7 @@
{
unsigned long num_sectors = (bytes + root->sectorsize - 1) /
root->sectorsize;
+ num_sectors++;
return sizeof(struct btrfs_ordered_sum) +
num_sectors * sizeof(struct btrfs_sector_sum);
}
@@ -114,7 +119,9 @@
u64 file_offset, u64 io_size);
int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
u64 start, u64 len);
-int btrfs_add_ordered_sum(struct inode *inode, struct btrfs_ordered_sum *sum);
+int btrfs_add_ordered_sum(struct inode *inode,
+ struct btrfs_ordered_extent *entry,
+ struct btrfs_ordered_sum *sum);
struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
u64 file_offset);
void btrfs_start_ordered_extent(struct inode *inode,