A 'lease_direct' lease requires that the vma have a valid MAP_DIRECT
mapping established. For xfs we use the generic_map_direct_lease()
handler for ->lease_direct(). It establishes a new lease and then checks
if the MAP_DIRECT mapping has been broken. We want to be sure that the
process will receive notification that the MAP_DIRECT mapping is being
torn down so it knows why other code paths are throwing failures.
For example in the RDMA/ibverbs case we want ibv_reg_mr() to fail if the
MAP_DIRECT mapping is invalid or in the process of being invalidated.
Cc: Jan Kara <jack@xxxxxxx>
Cc: Jeff Moyer <jmoyer@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>
Cc: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
Cc: Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
Cc: "J. Bruce Fields" <bfields@xxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
fs/xfs/xfs_file.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 4bee027c9366..bc512a9a8df5 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1157,6 +1157,7 @@ static const struct vm_operations_struct xfs_file_vm_direct_ops = {
.open = generic_map_direct_open,
.close = generic_map_direct_close,
+ .lease_direct = generic_map_direct_lease,
};
static const struct vm_operations_struct xfs_file_vm_ops = {
@@ -1209,8 +1210,8 @@ xfs_file_mmap_direct(
vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
/*
- * generic_map_direct_{open,close} expect ->vm_private_data is
- * set to the result of map_direct_register
+ * generic_map_direct_{open,close,lease} expect
+ * ->vm_private_data is set to the result of map_direct_register
*/
vma->vm_private_data = mds;
return 0;
--
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