1:09 p.m.
Introduce xfs_mmaplock_two_inodes_and_break_dax_layout() for dax files
who are going to be deduped. After that, call compare range function
only when files are both DAX or not.
Signed-off-by: Shiyang Ruan <ruansy.fnst(a)fujitsu.com>
---
fs/xfs/xfs_file.c | 2 +-
fs/xfs/xfs_inode.c | 66 +++++++++++++++++++++++++++++++++++++++++++-
fs/xfs/xfs_inode.h | 1 +
fs/xfs/xfs_reflink.c | 4 +--
4 files changed, 69 insertions(+), 4 deletions(-)
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 38d8eca05aee..bd5002d38df4 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -823,7 +823,7 @@ xfs_wait_dax_page(
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
}
-static int
+int
xfs_break_dax_layouts(
struct inode *inode,
bool *retry)
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 0369eb22c1bb..0774b6e2b940 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -3711,6 +3711,64 @@ xfs_iolock_two_inodes_and_break_layout(
return 0;
}
+static int
+xfs_mmaplock_two_inodes_and_break_dax_layout(
+ struct inode *src,
+ struct inode *dest)
+{
+ int error, attempts = 0;
+ bool retry;
+ struct xfs_inode *ip0, *ip1;
+ struct page *page;
+ struct xfs_log_item *lp;
+
+ if (src > dest)
+ swap(src, dest);
+ ip0 = XFS_I(src);
+ ip1 = XFS_I(dest);
+
+again:
+ retry = false;
+ /* Lock the first inode */
+ xfs_ilock(ip0, XFS_MMAPLOCK_EXCL);
+ error = xfs_break_dax_layouts(src, &retry);
+ if (error || retry) {
+ xfs_iunlock(ip0, XFS_MMAPLOCK_EXCL);
+ goto again;
+ }
+
+ if (src == dest)
+ return 0;
+
+ /* Nested lock the second inode */
+ lp = &ip0->i_itemp->ili_item;
+ if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
+ if (!xfs_ilock_nowait(ip1,
+ xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1))) {
+ xfs_iunlock(ip0, XFS_MMAPLOCK_EXCL);
+ if ((++attempts % 5) == 0)
+ delay(1); /* Don't just spin the CPU */
+ goto again;
+ }
+ } else
+ xfs_ilock(ip1, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1));
+ /*
+ * We cannot use xfs_break_dax_layouts() directly here because it may
+ * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable
+ * for this nested lock case.
+ */
+ page = dax_layout_busy_page(dest->i_mapping);
+ if (page) {
+ if (page_ref_count(page) != 1) {
+ xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
+ xfs_iunlock(ip0, XFS_MMAPLOCK_EXCL);
+ goto again;
+ }
+ }
+
+ return 0;
+}
+
/*
* Lock two inodes so that userspace cannot initiate I/O via file syscalls or
* mmap activity.
@@ -3721,10 +3779,16 @@ xfs_ilock2_io_mmap(
struct xfs_inode *ip2)
{
int ret;
+ struct inode *ino1 = VFS_I(ip1);
+ struct inode *ino2 = VFS_I(ip2);
- ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
+ ret = xfs_iolock_two_inodes_and_break_layout(ino1, ino2);
if (ret)
return ret;
+
+ if (IS_DAX(ino1) && IS_DAX(ino2))
+ return xfs_mmaplock_two_inodes_and_break_dax_layout(ino1, ino2);
+
if (ip1 == ip2)
xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
else
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index ca826cfba91c..2d0b344fb100 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -457,6 +457,7 @@ enum xfs_prealloc_flags {
int xfs_update_prealloc_flags(struct xfs_inode *ip,
enum xfs_prealloc_flags flags);
+int xfs_break_dax_layouts(struct inode *inode, bool *retry);
int xfs_break_layouts(struct inode *inode, uint *iolock,
enum layout_break_reason reason);
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 9a780948dbd0..ff308304c5cd 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1324,8 +1324,8 @@ xfs_reflink_remap_prep(
if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest))
goto out_unlock;
- /* Don't share DAX file data for now. */
- if (IS_DAX(inode_in) || IS_DAX(inode_out))
+ /* Don't share DAX file data with non-DAX file. */
+ if (IS_DAX(inode_in) != IS_DAX(inode_out))
goto out_unlock;
if (!IS_DAX(inode_in))
--
2.31.1