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authorJohannes Berg <johannes.berg@intel.com>2017-06-08 14:14:40 +0200
committerJohannes Berg <johannes.berg@intel.com>2017-06-08 14:14:45 +0200
commita43e61842ec55baa486d60eed2a19af67ba78b9f (patch)
tree6c3c93f19e3933273b73b9edd16edc146ab18527 /fs/dax.c
parent5d473fedd17ae3a9f92fb35551e307d01459ea6a (diff)
parent50dffe7fad6c156c2928e45c19ff7b86eb951f4c (diff)
Merge remote-tracking branch 'net-next/master' into mac80211-next
This brings in commit 7a7c0a6438b8 ("mac80211: fix TX aggregation start/stop callback race") to allow the follow-up cleanup. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'fs/dax.c')
-rw-r--r--fs/dax.c23
1 files changed, 23 insertions, 0 deletions
diff --git a/fs/dax.c b/fs/dax.c
index c22eaf162f95..2a6889b3585f 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1155,6 +1155,17 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf,
}
/*
+ * It is possible, particularly with mixed reads & writes to private
+ * mappings, that we have raced with a PMD fault that overlaps with
+ * the PTE we need to set up. If so just return and the fault will be
+ * retried.
+ */
+ if (pmd_trans_huge(*vmf->pmd) || pmd_devmap(*vmf->pmd)) {
+ vmf_ret = VM_FAULT_NOPAGE;
+ goto unlock_entry;
+ }
+
+ /*
* Note that we don't bother to use iomap_apply here: DAX required
* the file system block size to be equal the page size, which means
* that we never have to deal with more than a single extent here.
@@ -1398,6 +1409,18 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
goto fallback;
/*
+ * It is possible, particularly with mixed reads & writes to private
+ * mappings, that we have raced with a PTE fault that overlaps with
+ * the PMD we need to set up. If so just return and the fault will be
+ * retried.
+ */
+ if (!pmd_none(*vmf->pmd) && !pmd_trans_huge(*vmf->pmd) &&
+ !pmd_devmap(*vmf->pmd)) {
+ result = 0;
+ goto unlock_entry;
+ }
+
+ /*
* Note that we don't use iomap_apply here. We aren't doing I/O, only
* setting up a mapping, so really we're using iomap_begin() as a way
* to look up our filesystem block.