On 4/17/20 8:08 AM, Brian Foster wrote:
We use the same buffer I/O failure simulation code in a few
different places. It's not much code, but it's not necessarily
self-explanatory. Factor it into a helper and document it in one
place.
Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx>
Ok, looks ok to me:
Reviewed-by: Allison Collins <allison.henderson@xxxxxxxxxx>
---
fs/xfs/xfs_buf.c | 23 +++++++++++++++++++----
fs/xfs/xfs_buf.h | 1 +
fs/xfs/xfs_buf_item.c | 22 +++-------------------
fs/xfs/xfs_inode.c | 7 +------
4 files changed, 24 insertions(+), 29 deletions(-)
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 9ec3eaf1c618..93942d8e35dd 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1248,6 +1248,24 @@ xfs_buf_ioerror_alert(
-bp->b_error);
}
+/*
+ * To simulate an I/O failure, the buffer must be locked and held with at least
+ * three references. The LRU reference is dropped by the stale call. The buf
+ * item reference is dropped via ioend processing. The third reference is owned
+ * by the caller and is dropped on I/O completion if the buffer is XBF_ASYNC.
+ */
+void
+xfs_buf_iofail(
+ struct xfs_buf *bp,
+ int flags)
+{
+ bp->b_flags |= flags;
+ bp->b_flags &= ~XBF_DONE;
+ xfs_buf_stale(bp);
+ xfs_buf_ioerror(bp, -EIO);
+ xfs_buf_ioend(bp);
+}
+
int
xfs_bwrite(
struct xfs_buf *bp)
@@ -1480,10 +1498,7 @@ __xfs_buf_submit(
/* on shutdown we stale and complete the buffer immediately */
if (XFS_FORCED_SHUTDOWN(bp->b_mount)) {
- xfs_buf_ioerror(bp, -EIO);
- bp->b_flags &= ~XBF_DONE;
- xfs_buf_stale(bp);
- xfs_buf_ioend(bp);
+ xfs_buf_iofail(bp, 0);
return -EIO;
}
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index 9a04c53c2488..a6bce4702b2e 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -263,6 +263,7 @@ extern void __xfs_buf_ioerror(struct xfs_buf *bp, int error,
xfs_failaddr_t failaddr);
#define xfs_buf_ioerror(bp, err) __xfs_buf_ioerror((bp), (err), __this_address)
extern void xfs_buf_ioerror_alert(struct xfs_buf *bp, xfs_failaddr_t fa);
+void xfs_buf_iofail(struct xfs_buf *, int);
extern int __xfs_buf_submit(struct xfs_buf *bp, bool);
static inline int xfs_buf_submit(struct xfs_buf *bp)
diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 8796adde2d12..72d37a4609d8 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -471,28 +471,12 @@ xfs_buf_item_unpin(
xfs_buf_relse(bp);
} else if (freed && remove) {
/*
- * There are currently two references to the buffer - the active
- * LRU reference and the buf log item. What we are about to do
- * here - simulate a failed IO completion - requires 3
- * references.
- *
- * The LRU reference is removed by the xfs_buf_stale() call. The
- * buf item reference is removed by the xfs_buf_iodone()
- * callback that is run by xfs_buf_do_callbacks() during ioend
- * processing (via the bp->b_iodone callback), and then finally
- * the ioend processing will drop the IO reference if the buffer
- * is marked XBF_ASYNC.
- *
- * Hence we need to take an additional reference here so that IO
- * completion processing doesn't free the buffer prematurely.
+ * The buffer must be locked and held by the caller to simulate
+ * an async I/O failure.
*/
xfs_buf_lock(bp);
xfs_buf_hold(bp);
- bp->b_flags |= XBF_ASYNC;
- xfs_buf_ioerror(bp, -EIO);
- bp->b_flags &= ~XBF_DONE;
- xfs_buf_stale(bp);
- xfs_buf_ioend(bp);
+ xfs_buf_iofail(bp, XBF_ASYNC);
}
}
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index d1772786af29..b539ee221ce5 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -3629,12 +3629,7 @@ xfs_iflush_cluster(
* xfs_buf_submit().
*/
ASSERT(bp->b_iodone);
- bp->b_flags |= XBF_ASYNC;
- bp->b_flags &= ~XBF_DONE;
- xfs_buf_stale(bp);
- xfs_buf_ioerror(bp, -EIO);
- xfs_buf_ioend(bp);
-
+ xfs_buf_iofail(bp, XBF_ASYNC);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
/* abort the corrupt inode, as it was not attached to the buffer */
