libext2fs: allow callers to punch a single block
The range of blocks to punch is treated as an inclusive range on both
ends, i.e. if start=1 and end=2, both blocks 1 and 2 are punched out.
Thus, start == end means that the caller wishes to punch a single
block. Remove the check that prevents us from punching a single
block.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 326d5c1..e3920d0 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1308,6 +1308,10 @@
char *mtpt, int mtlen);
/* punch.c */
+/*
+ * NOTE: This function removes from an inode the blocks "start", "end", and
+ * every block in between.
+ */
extern errcode_t ext2fs_punch(ext2_filsys fs, ext2_ino_t ino,
struct ext2_inode *inode,
char *block_buf, blk64_t start,
diff --git a/lib/ext2fs/punch.c b/lib/ext2fs/punch.c
index 11c7668..aac1942 100644
--- a/lib/ext2fs/punch.c
+++ b/lib/ext2fs/punch.c
@@ -315,9 +315,6 @@
if (start > end)
return EINVAL;
- if (start == end)
- return 0;
-
/* Read inode structure if necessary */
if (!inode) {
retval = ext2fs_read_inode(fs, ino, &inode_buf);
@@ -332,7 +329,7 @@
if (start > ~0U)
return 0;
- count = ((end - start) < ~0U) ? (end - start) : ~0U;
+ count = ((end - start + 1) < ~0U) ? (end - start + 1) : ~0U;
retval = ext2fs_punch_ind(fs, inode, block_buf,
(blk_t) start, count);
}