ceph: allow sync_read/write return partial successed size of read/write.

Hi Sage:
This patch based on my previous patch"ceph: fix bugs about handling short-read for sync read mode".
I can't see this patch in ceph-client#testing.Maybe you forget it ?

Thanks!
Jianpeng Ma

For sync_read/write, it may do multi stripe operations.If one of those met erro, we return the former successed size rather than a error value. There is a exception for write-operation met -EOLDSNAPC.If this occur,we retry the whole write again.

Signed-off-by Jianpeng Ma <[email protected]>

---
 fs/ceph/file.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

fs/ceph/file.c +3 -2

index 69c4669..dd525c5 100644
@@ -373,7 +373,7 @@ more:
 			goto more;
 	}
 
-	if (ret >= 0) {
+	if (read > 0) {
 		ret = read;
 		/* did we bounce off eof? */
 		if (pos + left > inode->i_size)

@@ -611,7 +611,8 @@ out:
 		if (check_caps)
 			ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY,
 					NULL);
-	}
+	} else if (ret != -EOLDSNAPC && written > 0)
+		ret = written;
 	return ret;
 }
 

Signature · 2 lines

1.8.1.2
N?????r??y????b?X????v?^?)??{.n?+???z?]z???{ay??????,j??f???h???z??w??????j:+v???w?j?m????????zZ+???????j"??!?i

Quoted 3 lines · majianpeng

Hi Sage:
This patch based on my previous patch"ceph: fix bugs about handling short-read for sync read mode".
I can't see this patch in ceph-client#testing.Maybe you forget it ?

Whoops, I did! I've pulled both patches into the testing branch now.

Yan, did you want to look at this?

sage

Quoted 40 lines

Thanks!
Jianpeng Ma

For sync_read/write, it may do multi stripe operations.If one of those met erro, we return the former successed size rather than a error value. There is a exception for write-operation met -EOLDSNAPC.If this occur,we retry the whole write again.

Signed-off-by Jianpeng Ma <[email protected]>

---
 fs/ceph/file.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

fs/ceph/file.c +3 -2

index 69c4669..dd525c5 100644
@@ -373,7 +373,7 @@ more:
 			goto more;
 	}
 
-	if (ret >= 0) {
+	if (read > 0) {
 		ret = read;
 		/* did we bounce off eof? */
 		if (pos + left > inode->i_size)

@@ -611,7 +611,8 @@ out:
 		if (check_caps)
 			ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY,
 					NULL);
-	}
+	} else if (ret != -EOLDSNAPC && written > 0)
+		ret = written;
 	return ret;
 }
 

Signature · 2 lines

1.8.1.2
N?????r??y????b?X????v?^?)??{.n?+???z?]z???{ay??????,j??f???h???z??w??????j:+v???w?j?m????????zZ+???????j"??!?i