From a5084865524dee1fe8ea1fee17c60b4369ad4f5e Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <darrick.wong@oracle.com>
Date: Thu, 2 Jan 2020 13:25:00 -0800
Subject: [PATCH] xfs: introduce XFS_MAX_FILEOFF
Git-commit: a5084865524dee1fe8ea1fee17c60b4369ad4f5e
Patch-mainline: v5.6-rc1
References: bsc#1166166
Introduce a new #define for the maximum supported file block offset.
We'll use this in the next patch to make it more obvious that we're
doing some operation for all possible inode fork mappings after a given
offset. We can't use ULLONG_MAX here because bunmapi uses that to
detect when it's done.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>
---
fs/xfs/libxfs/xfs_format.h | 7 +++++++
fs/xfs/xfs_reflink.c | 3 ++-
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 1b7dcbae051c..77e9fa385980 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -1540,6 +1540,13 @@ typedef struct xfs_bmdr_block {
#define BMBT_BLOCKCOUNT_BITLEN 21
#define BMBT_STARTOFF_MASK ((1ULL << BMBT_STARTOFF_BITLEN) - 1)
+#define BMBT_BLOCKCOUNT_MASK ((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
+
+/*
+ * bmbt records have a file offset (block) field that is 54 bits wide, so this
+ * is the largest xfs_fileoff_t that we ever expect to see.
+ */
+#define XFS_MAX_FILEOFF (BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
typedef struct xfs_bmbt_rec {
__be64 l0, l1;
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index de451235c4ee..7a6c94295b8a 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1457,7 +1457,8 @@ xfs_reflink_clear_inode_flag(
* We didn't find any shared blocks so turn off the reflink flag.
* First, get rid of any leftover CoW mappings.
*/
- error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF, true);
+ error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, XFS_MAX_FILEOFF,
+ true);
if (error)
return error;
--
2.29.1