[PATCH v6.2 6/7] dax: Introduce dax_iomap_ops for end of reflink

From: Shiyang Ruan
Date: Fri Jul 09 2021 - 08:37:20 EST

After writing data, reflink requires end operations to remap those new
allocated extents. The current ->iomap_end() ignores the error code
returned from ->actor(), so we need to introduce this dax_iomap_ops and
change the dax_iomap_* interfaces to do this job.

- the dax_iomap_ops contains the original struct iomap_ops and fsdax
specific ->actor_end(), which is for the end operations of reflink
- also introduce dax specific zero_range, truncate_page
- create new dax_iomap_ops for ext2 and ext4

Then enable fsdax and reflink together in xfs.

Signed-off-by: Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx>
---
fs/dax.c | 105 +++++++++++++++++++++++++++++++++++------
fs/ext2/ext2.h | 3 ++
fs/ext2/file.c | 6 +--
fs/ext2/inode.c | 11 ++++-
fs/ext4/ext4.h | 3 ++
fs/ext4/file.c | 6 +--
fs/ext4/inode.c | 13 ++++-
fs/iomap/buffered-io.c | 6 +--
fs/xfs/xfs_bmap_util.c | 3 +-
fs/xfs/xfs_file.c | 8 ++--
fs/xfs/xfs_iomap.c | 36 +++++++++++++-
fs/xfs/xfs_iomap.h | 33 +++++++++++++
fs/xfs/xfs_iops.c | 7 ++-
fs/xfs/xfs_reflink.c | 3 +-
include/linux/dax.h | 28 +++++++++--
include/linux/iomap.h | 2 +
16 files changed, 228 insertions(+), 45 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index 93f16210847b..9285ea796668 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1240,7 +1240,7 @@ s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap,
}

static loff_t
-dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
+__dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
struct iomap *iomap, struct iomap *srcmap)
{
struct block_device *bdev = iomap->bdev;
@@ -1344,11 +1344,25 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
return done ? done : ret;
}

+static loff_t
+dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
+ struct iomap *iomap, struct iomap *srcmap)
+{
+ struct dax_iomap_data *idata = data;
+ loff_t ret = __dax_iomap_actor(inode, pos, length, idata->data,
+ iomap, srcmap);
+
+ if (idata->ops->actor_end)
+ ret = idata->ops->actor_end(inode, pos, length, ret);
+
+ return ret;
+}
+
/**
* dax_iomap_rw - Perform I/O to a DAX file
* @iocb: The control block for this I/O
* @iter: The addresses to do I/O from or to
- * @ops: iomap ops passed from the file system
+ * @ops: dax iomap ops passed from the file system
*
* This function performs read and write operations to directly mapped
* persistent memory. The callers needs to take care of read/write exclusion
@@ -1356,12 +1370,13 @@ dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
*/
ssize_t
dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
- const struct iomap_ops *ops)
+ const struct dax_iomap_ops *ops)
{
struct address_space *mapping = iocb->ki_filp->f_mapping;
struct inode *inode = mapping->host;
loff_t pos = iocb->ki_pos, ret = 0, done = 0;
unsigned flags = 0;
+ struct dax_iomap_data data = { iter, ops };

if (iov_iter_rw(iter) == WRITE) {
lockdep_assert_held_write(&inode->i_rwsem);
@@ -1374,8 +1389,8 @@ dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
flags |= IOMAP_NOWAIT;

while (iov_iter_count(iter)) {
- ret = iomap_apply(inode, pos, iov_iter_count(iter), flags, ops,
- iter, dax_iomap_actor);
+ ret = iomap_apply(inode, pos, iov_iter_count(iter), flags,
+ &ops->iomap_ops, &data, dax_iomap_actor);
if (ret <= 0)
break;
pos += ret;
@@ -1387,6 +1402,55 @@ dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
}
EXPORT_SYMBOL_GPL(dax_iomap_rw);

+static loff_t
+dax_iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t length,
+ void *data, struct iomap *iomap, struct iomap *srcmap)
+{
+ struct dax_iomap_data *idata = data;
+ loff_t ret = iomap_zero_range_actor(inode, pos, length, idata->data,
+ iomap, srcmap);
+
+ if (idata->ops->actor_end)
+ ret = idata->ops->actor_end(inode, pos, length, ret);
+
+ return ret;
+}
+
+int
+dax_iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
+ bool *did_zero, const struct dax_iomap_ops *ops)
+{
+ struct dax_iomap_data data = { did_zero, ops };
+ loff_t ret;
+
+ while (len > 0) {
+ ret = iomap_apply(inode, pos, len, IOMAP_ZERO, &ops->iomap_ops,
+ &data, dax_iomap_zero_range_actor);
+ if (ret <= 0)
+ return ret;
+
+ pos += ret;
+ len -= ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dax_iomap_zero_range);
+
+int
+dax_iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
+ const struct dax_iomap_ops *ops)
+{
+ unsigned int blocksize = i_blocksize(inode);
+ unsigned int off = pos & (blocksize - 1);
+
+ /* Block boundary? Nothing to do */
+ if (!off)
+ return 0;
+ return dax_iomap_zero_range(inode, pos, blocksize - off, did_zero, ops);
+}
+EXPORT_SYMBOL_GPL(dax_iomap_truncate_page);
+
static vm_fault_t dax_fault_return(int error)
{
if (error == 0)
@@ -1527,7 +1591,7 @@ static vm_fault_t dax_fault_actor(struct vm_fault *vmf, pfn_t *pfnp,
}

static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
- int *iomap_errp, const struct iomap_ops *ops)
+ int *iomap_errp, const struct dax_iomap_ops *dops)
{
struct vm_area_struct *vma = vmf->vma;
struct address_space *mapping = vma->vm_file->f_mapping;
@@ -1536,8 +1600,9 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
struct iomap iomap = { .type = IOMAP_HOLE };
struct iomap srcmap = { .type = IOMAP_HOLE };
+ const struct iomap_ops *ops = &dops->iomap_ops;
unsigned flags = IOMAP_FAULT;
- int error;
+ int error, copied = PAGE_SIZE;
bool write = vmf->flags & FAULT_FLAG_WRITE;
vm_fault_t ret = 0, major = 0;
void *entry;
@@ -1598,7 +1663,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
ret = dax_fault_actor(vmf, pfnp, &xas, &entry, false, flags,
&iomap, &srcmap);
if (ret == VM_FAULT_SIGBUS)
- goto finish_iomap;
+ goto finish_iomap_actor_end;

/* read/write MAPPED, CoW UNWRITTEN */
if (iomap.flags & IOMAP_F_NEW) {
@@ -1607,10 +1672,15 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
major = VM_FAULT_MAJOR;
}

+finish_iomap_actor_end:
+ if (dops->actor_end) {
+ if (ret & VM_FAULT_ERROR)
+ copied = 0;
+ dops->actor_end(inode, pos, PMD_SIZE, copied);
+ }
+
finish_iomap:
if (ops->iomap_end) {
- int copied = PAGE_SIZE;
-
if (ret & VM_FAULT_ERROR)
copied = 0;
/*
@@ -1663,7 +1733,7 @@ static bool dax_fault_check_fallback(struct vm_fault *vmf, struct xa_state *xas,
}

static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
- const struct iomap_ops *ops)
+ const struct dax_iomap_ops *dops)
{
struct vm_area_struct *vma = vmf->vma;
struct address_space *mapping = vma->vm_file->f_mapping;
@@ -1674,10 +1744,11 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
vm_fault_t ret = VM_FAULT_FALLBACK;
struct iomap iomap = { .type = IOMAP_HOLE };
struct iomap srcmap = { .type = IOMAP_HOLE };
+ const struct iomap_ops *ops = &dops->iomap_ops;
pgoff_t max_pgoff;
void *entry;
loff_t pos;
- int error;
+ int error, copied = PMD_SIZE;

/*
* Check whether offset isn't beyond end of file now. Caller is
@@ -1736,10 +1807,14 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
ret = dax_fault_actor(vmf, pfnp, &xas, &entry, true, flags,
&iomap, &srcmap);

+ if (dops->actor_end) {
+ if (ret == VM_FAULT_FALLBACK)
+ copied = 0;
+ dops->actor_end(inode, pos, PMD_SIZE, copied);
+ }
+
finish_iomap:
if (ops->iomap_end) {
- int copied = PMD_SIZE;
-
if (ret == VM_FAULT_FALLBACK)
copied = 0;
/*
@@ -1783,7 +1858,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
* successfully.
*/
vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
- pfn_t *pfnp, int *iomap_errp, const struct iomap_ops *ops)
+ pfn_t *pfnp, int *iomap_errp, const struct dax_iomap_ops *ops)
{
switch (pe_size) {
case PE_SIZE_PTE:
diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index b0a694820cb7..765269804f83 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -806,6 +806,9 @@ extern void ext2_set_file_ops(struct inode *inode);
extern const struct address_space_operations ext2_aops;
extern const struct address_space_operations ext2_nobh_aops;
extern const struct iomap_ops ext2_iomap_ops;
+#ifdef CONFIG_FS_DAX
+extern const struct dax_iomap_ops ext2_dax_iomap_ops;
+#endif

/* namei.c */
extern const struct inode_operations ext2_dir_inode_operations;
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index f98466acc672..d5dd82111128 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -39,7 +39,7 @@ static ssize_t ext2_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
return 0; /* skip atime */

inode_lock_shared(inode);
- ret = dax_iomap_rw(iocb, to, &ext2_iomap_ops);
+ ret = dax_iomap_rw(iocb, to, &ext2_dax_iomap_ops);
inode_unlock_shared(inode);

file_accessed(iocb->ki_filp);
@@ -63,7 +63,7 @@ static ssize_t ext2_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
if (ret)
goto out_unlock;

- ret = dax_iomap_rw(iocb, from, &ext2_iomap_ops);
+ ret = dax_iomap_rw(iocb, from, &ext2_dax_iomap_ops);
if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
i_size_write(inode, iocb->ki_pos);
mark_inode_dirty(inode);
@@ -102,7 +102,7 @@ static vm_fault_t ext2_dax_fault(struct vm_fault *vmf)
}
down_read(&ei->dax_sem);

- ret = dax_iomap_fault(vmf, PE_SIZE_PTE, NULL, NULL, &ext2_iomap_ops);
+ ret = dax_iomap_fault(vmf, PE_SIZE_PTE, NULL, NULL, &ext2_dax_iomap_ops);

up_read(&ei->dax_sem);
if (write)
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 68178b2234bd..a94744bbf82f 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -852,6 +852,13 @@ const struct iomap_ops ext2_iomap_ops = {
.iomap_begin = ext2_iomap_begin,
.iomap_end = ext2_iomap_end,
};
+
+const struct dax_iomap_ops ext2_dax_iomap_ops = {
+ .iomap_ops = {
+ .iomap_begin = ext2_iomap_begin,
+ .iomap_end = ext2_iomap_end,
+ },
+};
#else
/* Define empty ops for !CONFIG_FS_DAX case to avoid ugly ifdefs */
const struct iomap_ops ext2_iomap_ops;
@@ -1294,9 +1301,9 @@ static int ext2_setsize(struct inode *inode, loff_t newsize)
inode_dio_wait(inode);

if (IS_DAX(inode)) {
- error = iomap_zero_range(inode, newsize,
+ error = dax_iomap_zero_range(inode, newsize,
PAGE_ALIGN(newsize) - newsize, NULL,
- &ext2_iomap_ops);
+ &ext2_dax_iomap_ops);
} else if (test_opt(inode->i_sb, NOBH))
error = nobh_truncate_page(inode->i_mapping,
newsize, ext2_get_block);
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 37002663d521..b4e6df93dd82 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3773,6 +3773,9 @@ static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
}

extern const struct iomap_ops ext4_iomap_ops;
+#ifdef CONFIG_FS_DAX
+extern const struct dax_iomap_ops ext4_dax_iomap_ops;
+#endif
extern const struct iomap_ops ext4_iomap_overwrite_ops;
extern const struct iomap_ops ext4_iomap_report_ops;

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 816dedcbd541..a7a3497429ca 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -102,7 +102,7 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
/* Fallback to buffered IO in case we cannot support DAX */
return generic_file_read_iter(iocb, to);
}
- ret = dax_iomap_rw(iocb, to, &ext4_iomap_ops);
+ ret = dax_iomap_rw(iocb, to, &ext4_dax_iomap_ops);
inode_unlock_shared(inode);

file_accessed(iocb->ki_filp);
@@ -650,7 +650,7 @@ ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
ext4_journal_stop(handle);
}

- ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops);
+ ret = dax_iomap_rw(iocb, from, &ext4_dax_iomap_ops);

if (extend)
ret = ext4_handle_inode_extension(inode, offset, ret, count);
@@ -721,7 +721,7 @@ static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf,
} else {
down_read(&EXT4_I(inode)->i_mmap_sem);
}
- result = dax_iomap_fault(vmf, pe_size, &pfn, &error, &ext4_iomap_ops);
+ result = dax_iomap_fault(vmf, pe_size, &pfn, &error, &ext4_dax_iomap_ops);
if (write) {
ext4_journal_stop(handle);

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index fe6045a46599..2310f5cc6cd5 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3523,6 +3523,15 @@ const struct iomap_ops ext4_iomap_ops = {
.iomap_end = ext4_iomap_end,
};

+#ifdef CONFIG_FS_DAX
+const struct dax_iomap_ops ext4_dax_iomap_ops = {
+ .iomap_ops = {
+ .iomap_begin = ext4_iomap_begin,
+ .iomap_end = ext4_iomap_end,
+ },
+};
+#endif
+
const struct iomap_ops ext4_iomap_overwrite_ops = {
.iomap_begin = ext4_iomap_overwrite_begin,
.iomap_end = ext4_iomap_end,
@@ -3840,8 +3849,8 @@ static int ext4_block_zero_page_range(handle_t *handle,
length = max;

if (IS_DAX(inode)) {
- return iomap_zero_range(inode, from, length, NULL,
- &ext4_iomap_ops);
+ return dax_iomap_zero_range(inode, from, length, NULL,
+ &ext4_dax_iomap_ops);
}
return __ext4_block_zero_page_range(handle, mapping, from, length);
}
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index fdaac4ba9b9d..32c6b2ab6251 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -918,9 +918,9 @@ static s64 iomap_zero(struct inode *inode, loff_t pos, u64 length,
return iomap_write_end(inode, pos, bytes, bytes, page, iomap, srcmap);
}

-static loff_t iomap_zero_range_actor(struct inode *inode, loff_t pos,
- loff_t length, void *data, struct iomap *iomap,
- struct iomap *srcmap)
+loff_t
+iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t length,
+ void *data, struct iomap *iomap, struct iomap *srcmap)
{
bool *did_zero = data;
loff_t written = 0;
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 0936f3a96fe6..4b0744b5a75f 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1009,8 +1009,7 @@ xfs_free_file_space(
return 0;
if (offset + len > XFS_ISIZE(ip))
len = XFS_ISIZE(ip) - offset;
- error = iomap_zero_range(VFS_I(ip), offset, len, NULL,
- &xfs_buffered_write_iomap_ops);
+ error = xfs_iomap_zero_range(ip, offset, len, NULL);
if (error)
return error;

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 396ef36dcd0a..9bca68872242 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -281,7 +281,7 @@ xfs_file_dax_read(
ret = xfs_ilock_iocb(iocb, XFS_IOLOCK_SHARED);
if (ret)
return ret;
- ret = dax_iomap_rw(iocb, to, &xfs_read_iomap_ops);
+ ret = dax_iomap_rw(iocb, to, &xfs_dax_read_iomap_ops);
xfs_iunlock(ip, XFS_IOLOCK_SHARED);

file_accessed(iocb->ki_filp);
@@ -684,7 +684,7 @@ xfs_file_dax_write(
pos = iocb->ki_pos;

trace_xfs_file_dax_write(iocb, from);
- ret = dax_iomap_rw(iocb, from, &xfs_direct_write_iomap_ops);
+ ret = dax_iomap_rw(iocb, from, &xfs_dax_write_iomap_ops);
if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
i_size_write(inode, iocb->ki_pos);
error = xfs_setfilesize(ip, pos, ret);
@@ -1309,8 +1309,8 @@ __xfs_filemap_fault(

ret = dax_iomap_fault(vmf, pe_size, &pfn, NULL,
(write_fault && !vmf->cow_page) ?
- &xfs_direct_write_iomap_ops :
- &xfs_read_iomap_ops);
+ &xfs_dax_write_iomap_ops :
+ &xfs_dax_read_iomap_ops);
if (ret & VM_FAULT_NEEDDSYNC)
ret = dax_finish_sync_fault(vmf, pe_size, pfn);
} else {
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index d154f42e2dc6..48004cf28a88 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -761,7 +761,8 @@ xfs_direct_write_iomap_begin(

/* may drop and re-acquire the ilock */
error = xfs_reflink_allocate_cow(ip, &imap, &cmap, &shared,
- &lockmode, flags & IOMAP_DIRECT);
+ &lockmode,
+ (flags & IOMAP_DIRECT) || IS_DAX(inode));
if (error)
goto out_unlock;
if (shared)
@@ -854,6 +855,33 @@ const struct iomap_ops xfs_direct_write_iomap_ops = {
.iomap_begin = xfs_direct_write_iomap_begin,
};

+static int
+xfs_dax_write_iomap_actor_end(
+ struct inode *inode,
+ loff_t pos,
+ loff_t length,
+ ssize_t written)
+{
+ int error = 0;
+ struct xfs_inode *ip = XFS_I(inode);
+ bool cow = xfs_is_cow_inode(ip);
+
+ if (cow) {
+ if (written <= 0)
+ xfs_reflink_cancel_cow_range(ip, pos, length, true);
+ else
+ error = xfs_reflink_end_cow(ip, pos, written);
+ }
+ return error ?: written;
+}
+
+const struct dax_iomap_ops xfs_dax_write_iomap_ops = {
+ .iomap_ops = {
+ .iomap_begin = xfs_direct_write_iomap_begin,
+ },
+ .actor_end = xfs_dax_write_iomap_actor_end,
+};
+
static int
xfs_buffered_write_iomap_begin(
struct inode *inode,
@@ -1184,6 +1212,12 @@ const struct iomap_ops xfs_read_iomap_ops = {
.iomap_begin = xfs_read_iomap_begin,
};

+const struct dax_iomap_ops xfs_dax_read_iomap_ops = {
+ .iomap_ops = {
+ .iomap_begin = xfs_read_iomap_begin,
+ },
+};
+
static int
xfs_seek_iomap_begin(
struct inode *inode,
diff --git a/fs/xfs/xfs_iomap.h b/fs/xfs/xfs_iomap.h
index 7d3703556d0e..5eacb5d8ca88 100644
--- a/fs/xfs/xfs_iomap.h
+++ b/fs/xfs/xfs_iomap.h
@@ -45,5 +45,38 @@ extern const struct iomap_ops xfs_direct_write_iomap_ops;
extern const struct iomap_ops xfs_read_iomap_ops;
extern const struct iomap_ops xfs_seek_iomap_ops;
extern const struct iomap_ops xfs_xattr_iomap_ops;
+extern const struct dax_iomap_ops xfs_dax_write_iomap_ops;
+extern const struct dax_iomap_ops xfs_dax_read_iomap_ops;
+
+static inline int
+xfs_iomap_zero_range(
+ struct xfs_inode *ip,
+ loff_t pos,
+ loff_t len,
+ bool *did_zero)
+{
+ struct inode *inode = VFS_I(ip);
+
+ return IS_DAX(inode)
+ ? dax_iomap_zero_range(inode, pos, len, did_zero,
+ &xfs_dax_write_iomap_ops)
+ : iomap_zero_range(inode, pos, len, did_zero,
+ &xfs_buffered_write_iomap_ops);
+}
+
+static inline int
+xfs_iomap_truncate_page(
+ struct xfs_inode *ip,
+ loff_t pos,
+ bool *did_zero)
+{
+ struct inode *inode = VFS_I(ip);
+
+ return IS_DAX(inode)
+ ? dax_iomap_truncate_page(inode, pos, did_zero,
+ &xfs_dax_write_iomap_ops)
+ : iomap_truncate_page(inode, pos, did_zero,
+ &xfs_buffered_write_iomap_ops);
+}

#endif /* __XFS_IOMAP_H__*/
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index dfe24b7f26e5..6d936c3e1a6e 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -911,8 +911,8 @@ xfs_setattr_size(
*/
if (newsize > oldsize) {
trace_xfs_zero_eof(ip, oldsize, newsize - oldsize);
- error = iomap_zero_range(inode, oldsize, newsize - oldsize,
- &did_zeroing, &xfs_buffered_write_iomap_ops);
+ error = xfs_iomap_zero_range(ip, oldsize, newsize - oldsize,
+ &did_zeroing);
} else {
/*
* iomap won't detect a dirty page over an unwritten block (or a
@@ -924,8 +924,7 @@ xfs_setattr_size(
newsize);
if (error)
return error;
- error = iomap_truncate_page(inode, newsize, &did_zeroing,
- &xfs_buffered_write_iomap_ops);
+ error = xfs_iomap_truncate_page(ip, newsize, &did_zeroing);
}

if (error)
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index d25434f93235..9a780948dbd0 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1266,8 +1266,7 @@ xfs_reflink_zero_posteof(
return 0;

trace_xfs_zero_eof(ip, isize, pos - isize);
- return iomap_zero_range(VFS_I(ip), isize, pos - isize, NULL,
- &xfs_buffered_write_iomap_ops);
+ return xfs_iomap_zero_range(ip, isize, pos - isize, NULL);
}

/*
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 106d1f033a78..64393f6e96cf 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -3,6 +3,7 @@
#define _LINUX_DAX_H

#include <linux/fs.h>
+#include <linux/iomap.h>
#include <linux/mm.h>
#include <linux/radix-tree.h>

@@ -11,8 +12,6 @@

typedef unsigned long dax_entry_t;

-struct iomap_ops;
-struct iomap;
struct dax_device;
struct dax_operations {
/*
@@ -38,6 +37,23 @@ struct dax_operations {
int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
};

+struct dax_iomap_ops {
+ /* the original iomap ops */
+ struct iomap_ops iomap_ops;
+ /*
+ * actor_end: accept error code returned from ->actor(), deal with it
+ * before ->iomap_end()
+ */
+ int (*actor_end)(struct inode *, loff_t, loff_t, ssize_t);
+};
+
+/* dax iomap specific data, in order to call ->actor_end() in ->actor() */
+struct dax_iomap_data {
+ /* the original data pointer */
+ void *data;
+ const struct dax_iomap_ops *ops;
+};
+
extern struct attribute_group dax_attribute_group;

#if IS_ENABLED(CONFIG_DAX)
@@ -229,14 +245,18 @@ int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);

ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
- const struct iomap_ops *ops);
+ const struct dax_iomap_ops *ops);
vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
- pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
+ pfn_t *pfnp, int *errp, const struct dax_iomap_ops *ops);
vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
enum page_entry_size pe_size, pfn_t pfn);
int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
pgoff_t index);
+int dax_iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
+ bool *did_zero, const struct dax_iomap_ops *ops);
+int dax_iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
+ const struct dax_iomap_ops *ops);
s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap,
struct iomap *srcmap);
int dax_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 95562f863ad0..05437fbf5f68 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -178,6 +178,8 @@ int iomap_migrate_page(struct address_space *mapping, struct page *newpage,
#endif
int iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len,
const struct iomap_ops *ops);
+loff_t iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t length,
+ void *data, struct iomap *iomap, struct iomap *srcmap);
int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
bool *did_zero, const struct iomap_ops *ops);
int iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
--
2.32.0