This is just a PoC implementation of the option-1 which I was
mentioning in the previous email.
As mentioned, it is adding some flags & private pointer
to iomap infrastructure.
I would let upto you and others to comment on this approach.
Please note that I have run only few basic tests.
Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxx>
---
fs/ext4/ext4.h | 1 +
fs/ext4/file.c | 37 ++++++++++++++++++++++++++++++++++---
fs/ext4/inode.c | 31 +++++++++++++++++++++++++++++++
fs/iomap/direct-io.c | 16 +++++++++++++++-
fs/xfs/xfs_file.c | 3 ++-
include/linux/iomap.h | 5 ++++-
6 files changed, 87 insertions(+), 6 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 2ab91815f52d..93aa716c691e 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1555,6 +1555,7 @@ enum {
EXT4_STATE_NO_EXPAND, /* No space for expansion */
EXT4_STATE_DA_ALLOC_CLOSE, /* Alloc DA blks on close */
EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */
+ EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/
EXT4_STATE_NEWENTRY, /* File just added to dir */
EXT4_STATE_MAY_INLINE_DATA, /* may have in-inode data */
EXT4_STATE_EXT_PRECACHED, /* extents have been precached */
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 3736dbf28d0a..adfb56401312 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -314,8 +314,30 @@ static int ext4_handle_inode_extension(struct inode *inode, loff_t size,
return ret;
}
+static int ext4_dio_write_end_io_convert(struct inode *inode, loff_t offset,
+ ssize_t size, void *private)
+{
+ int ret = 0;
+ ext4_io_end_t *io_end = private;
+
+ if (!io_end) {
+ WARN_ON(!ext4_test_inode_state(inode,
+ EXT4_STATE_DIO_UNWRITTEN));
+ ret = ext4_convert_unwritten_extents(NULL, inode, offset, size);
+ if (ret)
+ return ret;
+ ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
+ } else {
+ io_end->offset = offset;
+ io_end->size = size;
+ ext4_put_io_end(io_end);
+ }
+ return ret;
+}
+
static int ext4_dio_write_end_io(struct kiocb *iocb, ssize_t size,
- ssize_t error, unsigned int flags)
+ ssize_t error, unsigned int flags,
+ void *private)
{
int ret = 0;
handle_t *handle;
@@ -345,12 +367,21 @@ static int ext4_dio_write_end_io(struct kiocb *iocb, ssize_t size,
ext4_orphan_del(handle, inode);
ext4_journal_stop(handle);
}
+
+ if (flags & IOMAP_DIO_UNWRITTEN) {
+ ret = ext4_dio_write_end_io_convert(inode, offset,
+ size, private);
+ if (ret < 0)
+ return ret;
+ }
+
return error;
}
if (flags & IOMAP_DIO_UNWRITTEN) {
- ret = ext4_convert_unwritten_extents(NULL, inode, offset, size);
- if (ret)
+ ret = ext4_dio_write_end_io_convert(inode, offset,
+ size, private);
+ if (ret < 0)
return ret;
}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 15715d22808d..9d77ed2aa58c 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3322,6 +3322,26 @@ static bool ext4_inode_datasync_dirty(struct inode *inode)
return inode->i_state & I_DIRTY_DATASYNC;
}
+static int ext4_iomap_init_io_end(struct inode *inode, struct iomap *iomap,
+ unsigned flags)
+{
+ ext4_io_end_t *io_end;
+
+ if (flags & IOMAP_DIRECT_AIO) {
+ if (flags & IOMAP_PRIVATE)
+ return 0;
+ io_end = ext4_init_io_end(inode, GFP_KERNEL);
+ if (!io_end)
+ return -ENOMEM;
+ iomap->private = io_end;
+ ext4_set_io_unwritten_flag(inode, io_end);
+ } else {
+ iomap->private = NULL;
+ ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
+ }
+ return 0;
+}
+
static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
unsigned flags, struct iomap *iomap)
{
@@ -3433,6 +3453,17 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
ret = ext4_map_blocks(handle, inode, &map,
EXT4_GET_BLOCKS_IO_CREATE_EXT);
}
+
+ if (map.m_flags & EXT4_MAP_UNWRITTEN) {
+ int err;
+
+ err = ext4_iomap_init_io_end(inode, iomap,
+ flags);
+ if (err < 0) {
+ ext4_journal_stop(handle);
+ return err;
+ }
+ }
}
if (ret < 0) {
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 2ccf1c6460d4..7d88683a0d93 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -17,6 +17,7 @@
* Private flags for iomap_dio, must not overlap with the public ones in
* iomap.h:
*/
+#define IOMAP_DIO_PRIVATE (1 << 27)
#define IOMAP_DIO_WRITE_FUA (1 << 28)
#define IOMAP_DIO_NEED_SYNC (1 << 29)
#define IOMAP_DIO_WRITE (1 << 30)
@@ -31,6 +32,7 @@ struct iomap_dio {
unsigned flags;
int error;
bool wait_for_completion;
+ void *private; /* FS specific */
union {
/* used during submission and for synchronous completion: */
@@ -78,7 +80,8 @@ static ssize_t iomap_dio_complete(struct iomap_dio *dio)
ssize_t ret;
if (dio->end_io)
- ret = dio->end_io(iocb, dio->size, dio->error, dio->flags);
+ ret = dio->end_io(iocb, dio->size, dio->error, dio->flags,
+ dio->private);
else
ret = dio->error;
@@ -363,6 +366,11 @@ iomap_dio_actor(struct inode *inode, loff_t pos, loff_t length,
{
struct iomap_dio *dio = data;
+ if (!(dio->flags & IOMAP_DIO_PRIVATE) && iomap->private) {
+ dio->private = iomap->private;
+ dio->flags |= IOMAP_DIO_PRIVATE;
+ }
+
switch (iomap->type) {
case IOMAP_HOLE:
if (WARN_ON_ONCE(dio->flags & IOMAP_DIO_WRITE))
@@ -421,6 +429,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
dio->end_io = end_io;
dio->error = 0;
dio->flags = 0;
+ dio->private = NULL;
dio->submit.iter = iter;
dio->submit.waiter = current;
@@ -458,6 +467,8 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
}
flags |= IOMAP_NOWAIT;
}
+ if (!is_sync_kiocb(iocb) && (flags & IOMAP_WRITE))
+ flags |= IOMAP_DIRECT_AIO;
ret = filemap_write_and_wait_range(mapping, start, end);
if (ret)
@@ -486,6 +497,9 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
blk_start_plug(&plug);
do {
+ if (dio->flags & IOMAP_DIO_PRIVATE)
+ flags |= IOMAP_PRIVATE;
+
ret = iomap_apply(inode, pos, count, flags, ops, dio,
iomap_dio_actor);
if (ret <= 0) {
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f2bc3ac4a60e..205c4219986c 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -370,7 +370,8 @@ xfs_dio_write_end_io(
struct kiocb *iocb,
ssize_t size,
ssize_t error,
- unsigned flags)
+ unsigned flags,
+ void *private)
{
struct inode *inode = file_inode(iocb->ki_filp);
struct xfs_inode *ip = XFS_I(inode);
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 900284e5c06c..57d3679442f9 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -102,6 +102,8 @@ struct iomap_page_ops {
#define IOMAP_FAULT (1 << 3) /* mapping for page fault */
#define IOMAP_DIRECT (1 << 4) /* direct I/O */
#define IOMAP_NOWAIT (1 << 5) /* do not block */
+#define IOMAP_DIRECT_AIO (1 << 6) /* AIO DIO */
+#define IOMAP_PRIVATE (1 << 7) /* FS specific */
struct iomap_ops {
/*
@@ -189,7 +191,8 @@ sector_t iomap_bmap(struct address_space *mapping, sector_t bno,
#define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */
#define IOMAP_DIO_COW (1 << 1) /* covers COW extent(s) */
typedef int (iomap_dio_end_io_t)(struct kiocb *iocb, ssize_t size,
- ssize_t error, unsigned int flags);
+ ssize_t error, unsigned int flags,
+ void *private);
ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
const struct iomap_ops *ops, iomap_dio_end_io_t end_io);
int iomap_dio_iopoll(struct kiocb *kiocb, bool spin);
--
2.21.0
