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| author | Ross Zwisler <ross.zwisler@linux.intel.com> | 2018-06-06 10:45:15 -0600 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2018-06-06 11:02:32 -0700 |
| commit | 546eb0317cfa3c4f9e1d9ab892766d65d7f78fad (patch) | |
| tree | bd07bde17c89b06bdf2bcf337b701c7cb3f0da9e /drivers/nvdimm | |
| parent | ce7f11a230d5b7165480b96c0cc7a90358b5b5e2 (diff) | |
| download | linux-546eb0317cfa3c4f9e1d9ab892766d65d7f78fad.tar.bz2 | |
libnvdimm, pmem: Do not flush power-fail protected CPU caches
This commit:
5fdf8e5ba566 ("libnvdimm: re-enable deep flush for pmem devices via fsync()")
intended to make sure that deep flush was always available even on
platforms which support a power-fail protected CPU cache. An unintended
side effect of this change was that we also lost the ability to skip
flushing CPU caches on those power-fail protected CPU cache.
Fix this by skipping the low level cache flushing in dax_flush() if we have
CPU caches which are power-fail protected. The user can still override this
behavior by manually setting the write_cache state of a namespace. See
libndctl's ndctl_namespace_write_cache_is_enabled(),
ndctl_namespace_enable_write_cache() and
ndctl_namespace_disable_write_cache() functions.
Cc: <stable@vger.kernel.org>
Fixes: 5fdf8e5ba566 ("libnvdimm: re-enable deep flush for pmem devices via fsync()")
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm')
| -rw-r--r-- | drivers/nvdimm/region_devs.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index a612be6f019d..ec3543b83330 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -1132,7 +1132,8 @@ EXPORT_SYMBOL_GPL(nvdimm_has_flush); int nvdimm_has_cache(struct nd_region *nd_region) { - return is_nd_pmem(&nd_region->dev); + return is_nd_pmem(&nd_region->dev) && + !test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags); } EXPORT_SYMBOL_GPL(nvdimm_has_cache); |