Re: [PATCH 2/4] fs/ntfs3: Fix fiemap + fix shrink file size (to remove preallocated space)

From: Kari Argillander
Date: Tue Oct 26 2021 - 17:19:20 EST


On Mon, Oct 25, 2021 at 07:58:57PM +0300, Konstantin Komarov wrote:
> Two problems:
> 1. ntfs3_setattr can't truncate preallocated space;
> 2. if allocated fragment "cross" valid size, then fragment splits into two parts:
> - normal part;
> - unwritten part (here we must return FIEMAP_EXTENT_LAST).
> Before this commit we returned FIEMAP_EXTENT_LAST for whole fragment.
> Fixes xfstest generic/092

I do not have time for now to got through more. Maybe you have some
ideas here.

generic/092 [21:16:19][ 18.906951] run fstests generic/092 at 2021-10-26 21:16:19
[21:16:22]- output mismatch (see /results/ntfs3/results-default/generic/092.out.bad)
--- tests/generic/092.out 2021-08-03 00:08:10.000000000 +0000
+++ /results/ntfs3/results-default/generic/092.out.bad 2021-10-26 21:16:22.127859289 +0000
@@ -2,5 +2,6 @@
wrote 5242880/5242880 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
0: [0..10239]: data
+1: [10240..20479]: unwritten
0: [0..10239]: data
1: [10240..20479]: unwritten

Argillander

> Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation")
>
> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
> ---
> fs/ntfs3/file.c | 2 +-
> fs/ntfs3/frecord.c | 10 +++++++---
> 2 files changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
> index 43b1451bff53..5418e5ba64b3 100644
> --- a/fs/ntfs3/file.c
> +++ b/fs/ntfs3/file.c
> @@ -761,7 +761,7 @@ int ntfs3_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
> }
> inode_dio_wait(inode);
>
> - if (attr->ia_size < oldsize)
> + if (attr->ia_size <= oldsize)
> err = ntfs_truncate(inode, attr->ia_size);
> else if (attr->ia_size > oldsize)
> err = ntfs_extend(inode, attr->ia_size, 0, NULL);
> diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c
> index 6f47a9c17f89..18842998c8fa 100644
> --- a/fs/ntfs3/frecord.c
> +++ b/fs/ntfs3/frecord.c
> @@ -1964,10 +1964,8 @@ int ni_fiemap(struct ntfs_inode *ni, struct fiemap_extent_info *fieinfo,
>
> vcn += clen;
>
> - if (vbo + bytes >= end) {
> + if (vbo + bytes >= end)
> bytes = end - vbo;
> - flags |= FIEMAP_EXTENT_LAST;
> - }
>
> if (vbo + bytes <= valid) {
> ;
> @@ -1977,6 +1975,9 @@ int ni_fiemap(struct ntfs_inode *ni, struct fiemap_extent_info *fieinfo,
> /* vbo < valid && valid < vbo + bytes */
> u64 dlen = valid - vbo;
>
> + if (vbo + dlen >= end)
> + flags |= FIEMAP_EXTENT_LAST;
> +
> err = fiemap_fill_next_extent(fieinfo, vbo, lbo, dlen,
> flags);
> if (err < 0)
> @@ -1995,6 +1996,9 @@ int ni_fiemap(struct ntfs_inode *ni, struct fiemap_extent_info *fieinfo,
> flags |= FIEMAP_EXTENT_UNWRITTEN;
> }
>
> + if (vbo + bytes >= end)
> + flags |= FIEMAP_EXTENT_LAST;
> +
> err = fiemap_fill_next_extent(fieinfo, vbo, lbo, bytes, flags);
> if (err < 0)
> break;
> --
> 2.33.0
>
>
>