diff --git a/include/linux/dax.h b/include/linux/dax.h index 70600b63083f9859746af1916b3d90e22bff4b26..aa148937bb3fb21bfe2f89dd9140f0ffd6fda74c 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -3,6 +3,7 @@ #include #include +#include #include /* We use lowest available exceptional entry bit for locking */ diff --git a/mm/filemap.c b/mm/filemap.c index f2479af09da91ae8767b009c294bef2e3e75fc2e..dfe55c2cfb34a94660f43f5294cfdf0ce3bf6f5c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -597,14 +597,21 @@ static int page_cache_tree_insert(struct address_space *mapping, if (!radix_tree_exceptional_entry(p)) return -EEXIST; - if (WARN_ON(dax_mapping(mapping))) - return -EINVAL; - - if (shadowp) - *shadowp = p; mapping->nrexceptional--; - if (node) - workingset_node_shadows_dec(node); + if (!dax_mapping(mapping)) { + if (shadowp) + *shadowp = p; + if (node) + workingset_node_shadows_dec(node); + } else { + /* DAX can replace empty locked entry with a hole */ + WARN_ON_ONCE(p != + (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY | + RADIX_DAX_ENTRY_LOCK)); + /* DAX accounts exceptional entries as normal pages */ + if (node) + workingset_node_pages_dec(node); + } } radix_tree_replace_slot(slot, page); mapping->nrpages++;