xfs: add error injection for per-AG resv failure

per-AG resv failure after fixing up freespace is hard to test in an
effective way, so directly add an error injection path to observe
such error handling path works as expected.

Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

diff --git a/fs/xfs/libxfs/xfs_ag_resv.c b/fs/xfs/libxfs/xfs_ag_resv.c
index fdfe6dc..6c5f8d1 100644 (file)
--- a/fs/xfs/libxfs/xfs_ag_resv.c
+++ b/fs/xfs/libxfs/xfs_ag_resv.c
@@ -211,7 +211,11 @@ __xfs_ag_resv_init(
                ASSERT(0);
                return -EINVAL;
        }
-       error = xfs_mod_fdblocks(mp, -(int64_t)hidden_space, true);
+
+       if (XFS_TEST_ERROR(false, mp, XFS_ERRTAG_AG_RESV_FAIL))
+               error = -ENOSPC;
+       else
+               error = xfs_mod_fdblocks(mp, -(int64_t)hidden_space, true);
        if (error) {
                trace_xfs_ag_resv_init_error(pag->pag_mount, pag->pag_agno,
                                error, _RET_IP_);

diff --git a/fs/xfs/libxfs/xfs_errortag.h b/fs/xfs/libxfs/xfs_errortag.h
index 6ca9084..a23a52e 100644 (file)
--- a/fs/xfs/libxfs/xfs_errortag.h
+++ b/fs/xfs/libxfs/xfs_errortag.h
@@ -58,7 +58,8 @@
 #define XFS_ERRTAG_BUF_IOERROR                         35
 #define XFS_ERRTAG_REDUCE_MAX_IEXTENTS                 36
 #define XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT            37
-#define XFS_ERRTAG_MAX                                 38
+#define XFS_ERRTAG_AG_RESV_FAIL                                38
+#define XFS_ERRTAG_MAX                                 39
 
 /*
  * Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
@@ -101,5 +102,6 @@
 #define XFS_RANDOM_BUF_IOERROR                         XFS_RANDOM_DEFAULT
 #define XFS_RANDOM_REDUCE_MAX_IEXTENTS                 1
 #define XFS_RANDOM_BMAP_ALLOC_MINLEN_EXTENT            1
+#define XFS_RANDOM_AG_RESV_FAIL                                1
 
 #endif /* __XFS_ERRORTAG_H_ */

diff --git a/fs/xfs/xfs_error.c b/fs/xfs/xfs_error.c
index 4d6509a..ce3bc1b 100644 (file)
--- a/fs/xfs/xfs_error.c
+++ b/fs/xfs/xfs_error.c
@@ -56,6 +56,7 @@ static unsigned int xfs_errortag_random_default[] = {
        XFS_RANDOM_BUF_IOERROR,
        XFS_RANDOM_REDUCE_MAX_IEXTENTS,
        XFS_RANDOM_BMAP_ALLOC_MINLEN_EXTENT,
+       XFS_RANDOM_AG_RESV_FAIL,
 };
 
 struct xfs_errortag_attr {
@@ -168,6 +169,7 @@ XFS_ERRORTAG_ATTR_RW(iunlink_fallback,      XFS_ERRTAG_IUNLINK_FALLBACK);
 XFS_ERRORTAG_ATTR_RW(buf_ioerror,      XFS_ERRTAG_BUF_IOERROR);
 XFS_ERRORTAG_ATTR_RW(reduce_max_iextents,      XFS_ERRTAG_REDUCE_MAX_IEXTENTS);
 XFS_ERRORTAG_ATTR_RW(bmap_alloc_minlen_extent, XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT);
+XFS_ERRORTAG_ATTR_RW(ag_resv_fail, XFS_ERRTAG_AG_RESV_FAIL);
 
 static struct attribute *xfs_errortag_attrs[] = {
        XFS_ERRORTAG_ATTR_LIST(noerror),
@@ -208,6 +210,7 @@ static struct attribute *xfs_errortag_attrs[] = {
        XFS_ERRORTAG_ATTR_LIST(buf_ioerror),
        XFS_ERRORTAG_ATTR_LIST(reduce_max_iextents),
        XFS_ERRORTAG_ATTR_LIST(bmap_alloc_minlen_extent),
+       XFS_ERRORTAG_ATTR_LIST(ag_resv_fail),
        NULL,
 };