summaryrefslogtreecommitdiff
path: root/drivers/nvdimm
diff options
context:
space:
mode:
authorVivek Goyal <vgoyal@redhat.com>2020-02-28 11:34:52 -0500
committerDan Williams <dan.j.williams@intel.com>2020-04-02 19:15:03 -0700
commitf605a263e0690177ecc180417eacf2b5507dd177 (patch)
tree119fa2ae9f57012c245a3926830911327b2721b5 /drivers/nvdimm
parent5d64efe79703c4de1f017af9f7643ead1dc85432 (diff)
downloadlwn-f605a263e0690177ecc180417eacf2b5507dd177.tar.gz
lwn-f605a263e0690177ecc180417eacf2b5507dd177.zip
dax, pmem: Add a dax operation zero_page_range
Add a dax operation zero_page_range, to zero a page. This will also clear any known poison in the page being zeroed. As of now, zeroing of one page is allowed in a single call. There are no callers which are trying to zero more than a page in a single call. Once we grow the callers which zero more than a page in single call, we can add that support. Primary reason for not doing that yet is that this will add little complexity in dm implementation where a range might be spanning multiple underlying targets and one will have to split the range into multiple sub ranges and call zero_page_range() on individual targets. Suggested-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Link: https://lore.kernel.org/r/20200228163456.1587-3-vgoyal@redhat.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm')
-rw-r--r--drivers/nvdimm/pmem.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 075b11682192..5b774ddd0efb 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -282,6 +282,16 @@ static const struct block_device_operations pmem_fops = {
.revalidate_disk = nvdimm_revalidate_disk,
};
+static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
+ size_t nr_pages)
+{
+ struct pmem_device *pmem = dax_get_private(dax_dev);
+
+ return blk_status_to_errno(pmem_do_write(pmem, ZERO_PAGE(0), 0,
+ PFN_PHYS(pgoff) >> SECTOR_SHIFT,
+ PAGE_SIZE));
+}
+
static long pmem_dax_direct_access(struct dax_device *dax_dev,
pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
{
@@ -313,6 +323,7 @@ static const struct dax_operations pmem_dax_ops = {
.dax_supported = generic_fsdax_supported,
.copy_from_iter = pmem_copy_from_iter,
.copy_to_iter = pmem_copy_to_iter,
+ .zero_page_range = pmem_dax_zero_page_range,
};
static const struct attribute_group *pmem_attribute_groups[] = {