summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-01-01 12:27:05 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-01 12:27:05 -0800
commit4759d386d55fef452d692bf101167914437e848e (patch)
treee7109c192ec589fcea2a98f9702aa3c0e4009581 /mm
parent238d1d0f79f619d75c2cc741d6770fb0986aef24 (diff)
parent1db175428ee374489448361213e9c3b749d14900 (diff)
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull DAX updates from Dan Williams: "The completion of Jan's DAX work for 4.10. As I mentioned in the libnvdimm-for-4.10 pull request, these are some final fixes for the DAX dirty-cacheline-tracking invalidation work that was merged through the -mm, ext4, and xfs trees in -rc1. These patches were prepared prior to the merge window, but we waited for 4.10-rc1 to have a stable merge base after all the prerequisites were merged. Quoting Jan on the overall changes in these patches: "So I'd like all these 6 patches to go for rc2. The first three patches fix invalidation of exceptional DAX entries (a bug which is there for a long time) - without these patches data loss can occur on power failure even though user called fsync(2). The other three patches change locking of DAX faults so that ->iomap_begin() is called in a more relaxed locking context and we are safe to start a transaction there for ext4" These have received a build success notification from the kbuild robot, and pass the latest libnvdimm unit tests. There have not been any -next releases since -rc1, so they have not appeared there" * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: ext4: Simplify DAX fault path dax: Call ->iomap_begin without entry lock during dax fault dax: Finish fault completely when loading holes dax: Avoid page invalidation races and unnecessary radix tree traversals mm: Invalidate DAX radix tree entries only if appropriate ext2: Return BH_New buffers for zeroed blocks
Diffstat (limited to 'mm')
-rw-r--r--mm/truncate.c75
1 files changed, 61 insertions, 14 deletions
diff --git a/mm/truncate.c b/mm/truncate.c
index fd97f1dbce29..dd7b24e083c5 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -24,20 +24,12 @@
#include <linux/rmap.h>
#include "internal.h"
-static void clear_exceptional_entry(struct address_space *mapping,
- pgoff_t index, void *entry)
+static void clear_shadow_entry(struct address_space *mapping, pgoff_t index,
+ void *entry)
{
struct radix_tree_node *node;
void **slot;
- /* Handled by shmem itself */
- if (shmem_mapping(mapping))
- return;
-
- if (dax_mapping(mapping)) {
- dax_delete_mapping_entry(mapping, index);
- return;
- }
spin_lock_irq(&mapping->tree_lock);
/*
* Regular page slots are stabilized by the page lock even
@@ -55,6 +47,56 @@ unlock:
spin_unlock_irq(&mapping->tree_lock);
}
+/*
+ * Unconditionally remove exceptional entry. Usually called from truncate path.
+ */
+static void truncate_exceptional_entry(struct address_space *mapping,
+ pgoff_t index, void *entry)
+{
+ /* Handled by shmem itself */
+ if (shmem_mapping(mapping))
+ return;
+
+ if (dax_mapping(mapping)) {
+ dax_delete_mapping_entry(mapping, index);
+ return;
+ }
+ clear_shadow_entry(mapping, index, entry);
+}
+
+/*
+ * Invalidate exceptional entry if easily possible. This handles exceptional
+ * entries for invalidate_inode_pages() so for DAX it evicts only unlocked and
+ * clean entries.
+ */
+static int invalidate_exceptional_entry(struct address_space *mapping,
+ pgoff_t index, void *entry)
+{
+ /* Handled by shmem itself */
+ if (shmem_mapping(mapping))
+ return 1;
+ if (dax_mapping(mapping))
+ return dax_invalidate_mapping_entry(mapping, index);
+ clear_shadow_entry(mapping, index, entry);
+ return 1;
+}
+
+/*
+ * Invalidate exceptional entry if clean. This handles exceptional entries for
+ * invalidate_inode_pages2() so for DAX it evicts only clean entries.
+ */
+static int invalidate_exceptional_entry2(struct address_space *mapping,
+ pgoff_t index, void *entry)
+{
+ /* Handled by shmem itself */
+ if (shmem_mapping(mapping))
+ return 1;
+ if (dax_mapping(mapping))
+ return dax_invalidate_mapping_entry_sync(mapping, index);
+ clear_shadow_entry(mapping, index, entry);
+ return 1;
+}
+
/**
* do_invalidatepage - invalidate part or all of a page
* @page: the page which is affected
@@ -262,7 +304,8 @@ void truncate_inode_pages_range(struct address_space *mapping,
break;
if (radix_tree_exceptional_entry(page)) {
- clear_exceptional_entry(mapping, index, page);
+ truncate_exceptional_entry(mapping, index,
+ page);
continue;
}
@@ -351,7 +394,8 @@ void truncate_inode_pages_range(struct address_space *mapping,
}
if (radix_tree_exceptional_entry(page)) {
- clear_exceptional_entry(mapping, index, page);
+ truncate_exceptional_entry(mapping, index,
+ page);
continue;
}
@@ -470,7 +514,8 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping,
break;
if (radix_tree_exceptional_entry(page)) {
- clear_exceptional_entry(mapping, index, page);
+ invalidate_exceptional_entry(mapping, index,
+ page);
continue;
}
@@ -592,7 +637,9 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
break;
if (radix_tree_exceptional_entry(page)) {
- clear_exceptional_entry(mapping, index, page);
+ if (!invalidate_exceptional_entry2(mapping,
+ index, page))
+ ret = -EBUSY;
continue;
}