[PATCH 2/3] dax: introduce dax_clear_poison to dax pwrite operation
From: Jane Chu <hidden>
Date: 2021-09-14 23:32:38
Also in:
lkml, nvdimm
Subsystem:
filesystem direct access (dax), filesystems (vfs and infrastructure), the rest · Maintainers:
Dan Williams, Alexander Viro, Christian Brauner, Linus Torvalds
When pwrite(2) encounters poison in a dax range, it fails with EIO. But if the backend hardware of the dax device is capable of clearing poison, try that and resume the write. Signed-off-by: Jane Chu <redacted> --- fs/dax.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/fs/dax.c b/fs/dax.c
index 99b4e78d888f..592a156abbf2 100644
--- a/fs/dax.c
+++ b/fs/dax.c@@ -1156,8 +1156,17 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data, if (ret) break; + /* + * If WRITE operation encounters media error in a page aligned + * range, try to clear the error, then resume, for just once. + */ map_len = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size), &kaddr, NULL); + if ((map_len == -EIO) && (iov_iter_rw(iter) == WRITE)) { + if (dax_clear_poison(dax_dev, pgoff, PHYS_PFN(size)) == 0) + map_len = dax_direct_access(dax_dev, pgoff, + PHYS_PFN(size), &kaddr, NULL); + } if (map_len < 0) { ret = map_len; break;
--
2.18.4