]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - fs/dax.c
Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block
[karo-tx-linux.git] / fs / dax.c
index 2bfbcd72604756643f46500c7e33812a2e5a138d..6433650be833876eea42cd36ca109e4298bff073 100644 (file)
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -373,6 +373,22 @@ restart:
                }
                spin_lock_irq(&mapping->tree_lock);
 
+               if (!entry) {
+                       /*
+                        * We needed to drop the page_tree lock while calling
+                        * radix_tree_preload() and we didn't have an entry to
+                        * lock.  See if another thread inserted an entry at
+                        * our index during this time.
+                        */
+                       entry = __radix_tree_lookup(&mapping->page_tree, index,
+                                       NULL, &slot);
+                       if (entry) {
+                               radix_tree_preload_end();
+                               spin_unlock_irq(&mapping->tree_lock);
+                               goto restart;
+                       }
+               }
+
                if (pmd_downgrade) {
                        radix_tree_delete(&mapping->page_tree, index);
                        mapping->nrexceptional--;
@@ -388,19 +404,12 @@ restart:
                if (err) {
                        spin_unlock_irq(&mapping->tree_lock);
                        /*
-                        * Someone already created the entry?  This is a
-                        * normal failure when inserting PMDs in a range
-                        * that already contains PTEs.  In that case we want
-                        * to return -EEXIST immediately.
-                        */
-                       if (err == -EEXIST && !(size_flag & RADIX_DAX_PMD))
-                               goto restart;
-                       /*
-                        * Our insertion of a DAX PMD entry failed, most
-                        * likely because it collided with a PTE sized entry
-                        * at a different index in the PMD range.  We haven't
-                        * inserted anything into the radix tree and have no
-                        * waiters to wake.
+                        * Our insertion of a DAX entry failed, most likely
+                        * because we were inserting a PMD entry and it
+                        * collided with a PTE sized entry at a different
+                        * index in the PMD range.  We haven't inserted
+                        * anything into the radix tree and have no waiters to
+                        * wake.
                         */
                        return ERR_PTR(err);
                }