[PATCH 02/25] vfs: vfs_clone_file_prep_inodes should return EINVAL for a clone from beyond EOF

[Darrick J. Wong]

From: Darrick J. Wong 

vfs_clone_file_prep_inodes cannot return 0 if it is asked to remap from
a zero byte file because that's what btrfs does.

Signed-off-by: Darrick J. Wong 
Reviewed-by: Christoph Hellwig 
---
 fs/read_write.c |3 ---
 1 file changed, 3 deletions(-)


diff --git a/fs/read_write.c b/fs/read_write.c
index 8a2737f0d61d..260797b01851 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1740,10 +1740,7 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, 
loff_t pos_in,
if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
return -EINVAL;
 
-   /* Are we going all the way to the end? */
isize = i_size_read(inode_in);
-   if (isize == 0)
-   return 0;
 
/* Zero length dedupe exits immediately; reflink goes to EOF. */
if (*len == 0) {

Re: [PATCH 02/25] vfs: vfs_clone_file_prep_inodes should return EINVAL for a clone from beyond EOF

[Christoph Hellwig]

On Wed, Oct 10, 2018 at 09:12:30PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong 
> 
> vfs_clone_file_prep_inodes cannot return 0 if it is asked to remap from
> a zero byte file because that's what btrfs does.
> 
> Signed-off-by: Darrick J. Wong 
> ---

Maybe it would be a good time to switch btrfs to use
vfs_clone_file_prep_inodes so that we don't have any discrepancies?

Otherwise looks good:

Reviewed-by: Christoph Hellwig 

[PATCH 02/25] vfs: vfs_clone_file_prep_inodes should return EINVAL for a clone from beyond EOF

[Darrick J. Wong]

From: Darrick J. Wong 

vfs_clone_file_prep_inodes cannot return 0 if it is asked to remap from
a zero byte file because that's what btrfs does.

Signed-off-by: Darrick J. Wong 
---
 fs/read_write.c |3 ---
 1 file changed, 3 deletions(-)


diff --git a/fs/read_write.c b/fs/read_write.c
index 8a2737f0d61d..260797b01851 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1740,10 +1740,7 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, 
loff_t pos_in,
if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
return -EINVAL;
 
-   /* Are we going all the way to the end? */
isize = i_size_read(inode_in);
-   if (isize == 0)
-   return 0;
 
/* Zero length dedupe exits immediately; reflink goes to EOF. */
if (*len == 0) {