Re: [PATCH v3 07/10] iomap: Introduce iomap_apply2() for operations on two files
On 21/03/19 09:52AM, Shiyang Ruan wrote:
> Some operations, such as comparing a range of data in two files under
> fsdax mode, requires nested iomap_open()/iomap_end() on two file. Thus,
> we introduce iomap_apply2() to accept arguments from two files and
> iomap_actor2_t for actions on two files.
>
> Signed-off-by: Shiyang Ruan
> ---
> fs/iomap/apply.c | 56 +++
> include/linux/iomap.h | 7 +-
> 2 files changed, 62 insertions(+), 1 deletion(-)
>
> diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c
> index 26ab6563181f..fbc38ce3d5b6 100644
> --- a/fs/iomap/apply.c
> +++ b/fs/iomap/apply.c
> @@ -97,3 +97,59 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t
> length, unsigned flags,
>
> return written ? written : ret;
> }
> +
> +loff_t
> +iomap_apply2(struct inode *ino1, loff_t pos1, struct inode *ino2, loff_t
> pos2,
> + loff_t length, unsigned int flags, const struct iomap_ops *ops,
> + void *data, iomap_actor2_t actor)
> +{
> + struct iomap smap = { .type = IOMAP_HOLE };
> + struct iomap dmap = { .type = IOMAP_HOLE };
> + loff_t written = 0, ret, ret2 = 0;
> + loff_t len1 = length, len2, min_len;
> +
> + ret = ops->iomap_begin(ino1, pos1, len1, flags, , NULL);
> + if (ret)
> + goto out_src;
if above call fails we need not call ->iomap_end() on smap.
> + if (WARN_ON(smap.offset > pos1)) {
> + written = -EIO;
> + goto out_src;
> + }
> + if (WARN_ON(smap.length == 0)) {
> + written = -EIO;
> + goto out_src;
> + }
> + len2 = min_t(loff_t, len1, smap.length);
> +
> + ret = ops->iomap_begin(ino2, pos2, len2, flags, , NULL);
> + if (ret)
> + goto out_dest;
ditto
> + if (WARN_ON(dmap.offset > pos2)) {
> + written = -EIO;
> + goto out_dest;
> + }
> + if (WARN_ON(dmap.length == 0)) {
> + written = -EIO;
> + goto out_dest;
> + }
> + min_len = min_t(loff_t, len2, dmap.length);
> +
> + written = actor(ino1, pos1, ino2, pos2, min_len, data, , );
> +
> +out_dest:
> + if (ops->iomap_end)
> + ret2 = ops->iomap_end(ino2, pos2, len2,
> + written > 0 ? written : 0, flags, );
> +out_src:
> + if (ops->iomap_end)
> + ret = ops->iomap_end(ino1, pos1, len1,
> + written > 0 ? written : 0, flags, );
> +
I guess, this maynot be a problem, but I still think we should be
consistent w.r.t len argument we are passing in ->iomap_end() for both type of
iomap_apply* family of functions.
IIUC, we used to call ->iomap_end() with the length argument filled by the
filesystem from ->iomap_begin() call.
whereas above breaks that behavior. Although I don't think this is FATAL, but
still it is better to be consistent with the APIs.
Thoughts?
> + if (ret)
> + return written ? written : ret;
> +
> + if (ret2)
> + return written ? written : ret2;
> +
> + return written;
> +}
if (written)
return written;
return ret ? ret : ret2;
Is above a simpler version?
-ritesh
[PATCH v3 07/10] iomap: Introduce iomap_apply2() for operations on two files
Some operations, such as comparing a range of data in two files under
fsdax mode, requires nested iomap_open()/iomap_end() on two file. Thus,
we introduce iomap_apply2() to accept arguments from two files and
iomap_actor2_t for actions on two files.
Signed-off-by: Shiyang Ruan
---
fs/iomap/apply.c | 56 +++
include/linux/iomap.h | 7 +-
2 files changed, 62 insertions(+), 1 deletion(-)
diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c
index 26ab6563181f..fbc38ce3d5b6 100644
--- a/fs/iomap/apply.c
+++ b/fs/iomap/apply.c
@@ -97,3 +97,59 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length,
unsigned flags,
return written ? written : ret;
}
+
+loff_t
+iomap_apply2(struct inode *ino1, loff_t pos1, struct inode *ino2, loff_t pos2,
+ loff_t length, unsigned int flags, const struct iomap_ops *ops,
+ void *data, iomap_actor2_t actor)
+{
+ struct iomap smap = { .type = IOMAP_HOLE };
+ struct iomap dmap = { .type = IOMAP_HOLE };
+ loff_t written = 0, ret, ret2 = 0;
+ loff_t len1 = length, len2, min_len;
+
+ ret = ops->iomap_begin(ino1, pos1, len1, flags, , NULL);
+ if (ret)
+ goto out_src;
+ if (WARN_ON(smap.offset > pos1)) {
+ written = -EIO;
+ goto out_src;
+ }
+ if (WARN_ON(smap.length == 0)) {
+ written = -EIO;
+ goto out_src;
+ }
+ len2 = min_t(loff_t, len1, smap.length);
+
+ ret = ops->iomap_begin(ino2, pos2, len2, flags, , NULL);
+ if (ret)
+ goto out_dest;
+ if (WARN_ON(dmap.offset > pos2)) {
+ written = -EIO;
+ goto out_dest;
+ }
+ if (WARN_ON(dmap.length == 0)) {
+ written = -EIO;
+ goto out_dest;
+ }
+ min_len = min_t(loff_t, len2, dmap.length);
+
+ written = actor(ino1, pos1, ino2, pos2, min_len, data, , );
+
+out_dest:
+ if (ops->iomap_end)
+ ret2 = ops->iomap_end(ino2, pos2, len2,
+ written > 0 ? written : 0, flags, );
+out_src:
+ if (ops->iomap_end)
+ ret = ops->iomap_end(ino1, pos1, len1,
+written > 0 ? written : 0, flags, );
+
+ if (ret)
+ return written ? written : ret;
+
+ if (ret2)
+ return written ? written : ret2;
+
+ return written;
+}
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 5bd3cac4df9c..913f98897a77 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -148,10 +148,15 @@ struct iomap_ops {
*/
typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len,
void *data, struct iomap *iomap, struct iomap *srcmap);
-
+typedef loff_t (*iomap_actor2_t)(struct inode *ino1, loff_t pos1,
+ struct inode *ino2, loff_t pos2, loff_t len, void *data,
+ struct iomap *smap, struct iomap *dmap);
loff_t iomap_apply(struct inode *inode, loff_t pos, loff_t length,
unsigned flags, const struct iomap_ops *ops, void *data,
iomap_actor_t actor);
+loff_t iomap_apply2(struct inode *ino1, loff_t pos1, struct inode *ino2,
+ loff_t pos2, loff_t length, unsigned int flags,
+ const struct iomap_ops *ops, void *data, iomap_actor2_t actor);
ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from,
const struct iomap_ops *ops);
--
2.30.1
