在 2022/3/30 14:00, Christoph Hellwig 写道:
@@ -1892,6 +1893,8 @@ xfs_free_buftarg(
list_lru_destroy(&btp->bt_lru);
blkdev_issue_flush(btp->bt_bdev);
+ if (btp->bt_daxdev)
+ dax_unregister_holder(btp->bt_daxdev, btp->bt_mount);
fs_put_dax(btp->bt_daxdev);
kmem_free(btp);
@@ -1939,6 +1942,7 @@ xfs_alloc_buftarg(
struct block_device *bdev)
{
xfs_buftarg_t *btp;
+ int error;
btp = kmem_zalloc(sizeof(*btp), KM_NOFS);
@@ -1946,6 +1950,14 @@ xfs_alloc_buftarg(
btp->bt_dev = bdev->bd_dev;
btp->bt_bdev = bdev;
btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off);
+ if (btp->bt_daxdev) {
+ error = dax_register_holder(btp->bt_daxdev, mp,
+ &xfs_dax_holder_operations);
+ if (error) {
+ xfs_err(mp, "DAX device already in use?!");
+ goto error_free;
+ }
+ }
It seems to me that just passing the holder and holder ops to
fs_dax_get_by_bdev and the holder to dax_unregister_holder would
significantly simply the interface here.
Dan, what do you think?
+#if IS_ENABLED(CONFIG_MEMORY_FAILURE) && IS_ENABLED(CONFIG_FS_DAX)
No real need for the IS_ENABLED. Also any reason to even build this
file if the options are not set? It seems like
xfs_dax_holder_operations should just be defined to NULL and the
whole file not supported if we can't support the functionality.
Got it. These two CONFIG seem not related for now. So, I think I
should wrap these code with #ifdef CONFIG_MEMORY_FAILURE here, and add
`xfs-$(CONFIG_FS_DAX) += xfs_notify_failure.o` in the makefile.
Dan: not for this series, but is there any reason not to require
MEMORY_FAILURE for DAX to start with?
+
+ ddev_start = mp->m_ddev_targp->bt_dax_part_off;
+ ddev_end = ddev_start +
+ (mp->m_ddev_targp->bt_bdev->bd_nr_sectors << SECTOR_SHIFT) - 1;
This should use bdev_nr_bytes.
OK.
But didn't we say we don't want to support notifications on partitioned
devices and thus don't actually need all this?
+
+ /* Ignore the range out of filesystem area */
+ if ((offset + len) < ddev_start)
No need for the inner braces.
+ if ((offset + len) > ddev_end)
No need for the braces either.
Really no need? It is to make sure the range to be handled won't out of
the filesystem area. And make sure the @offset and @len are valid and
correct after subtract the bbdev_start.
diff --git a/fs/xfs/xfs_notify_failure.h b/fs/xfs/xfs_notify_failure.h
new file mode 100644
index 000000000000..76187b9620f9
--- /dev/null
+++ b/fs/xfs/xfs_notify_failure.h
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Fujitsu. All Rights Reserved.
+ */
+#ifndef __XFS_NOTIFY_FAILURE_H__
+#define __XFS_NOTIFY_FAILURE_H__
+
+extern const struct dax_holder_operations xfs_dax_holder_operations;
+
+#endif /* __XFS_NOTIFY_FAILURE_H__ */
Dowe really need a new header for this vs just sequeezing it into
xfs_super.h or something like that?
Yes, I'll move it into xfs_super.h. The xfs_notify_failure.c was
splitted from xfs_super.c in the old patch. There is no need to create
a header file for only single line of code.
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index e8f37bdc8354..b8de6ed2c888 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -353,6 +353,12 @@ xfs_setup_dax_always(
return -EINVAL;
}
+ if (xfs_has_reflink(mp) && !xfs_has_rmapbt(mp)) {
+ xfs_alert(mp,
+ "need rmapbt when both DAX and reflink enabled.");
+ return -EINVAL;
+ }
Right now we can't even enable reflink with DAX yet, so adding this
here seems premature - it should go into the patch allowing DAX+reflink.
Yes. I'll remove it for now.
--
Thanks,
Ruan.
