diff options
| author | Mike Snitzer <snitzer@kernel.org> | 2025-09-19 10:36:31 -0400 |
|---|---|---|
| committer | Anna Schumaker <anna.schumaker@oracle.com> | 2025-09-30 16:10:30 -0400 |
| commit | 1f0d4ab0f5326ab6f940482b1941d2209d61285a (patch) | |
| tree | 3200783d66fb8f4d2d053b7147ff4acf066a63d1 | |
| parent | cda94457c224915845b1d209ff71cad3c61ce194 (diff) | |
NFS: add basic STATX_DIOALIGN and STATX_DIO_READ_ALIGN support
NFS doesn't have DIO alignment constraints, so have NFS respond with
accommodating DIO alignment attributes (rather than plumb in GETATTR
support for STATX_DIOALIGN and STATX_DIO_READ_ALIGN).
The most coarse-grained dio_offset_align is the most accommodating
(e.g. PAGE_SIZE, in future larger may be supported).
Now that NFS has support, NFS reexport will now handle unaligned DIO
(NFSD's NFSD_IO_DIRECT support requires the underlying filesystem
support STATX_DIOALIGN and/or STATX_DIO_READ_ALIGN).
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
| -rw-r--r-- | fs/nfs/inode.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 49df9debb1a6..84bf3d21c25c 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -1073,6 +1073,21 @@ out_no_revalidate: if (S_ISDIR(inode->i_mode)) stat->blksize = NFS_SERVER(inode)->dtsize; stat->btime = NFS_I(inode)->btime; + + /* Special handling for STATX_DIOALIGN and STATX_DIO_READ_ALIGN + * - NFS doesn't have DIO alignment constraints, avoid getting + * these DIO attrs from remote and just respond with most + * accommodating limits (so client will issue supported DIO). + * - this is unintuitive, but the most coarse-grained + * dio_offset_align is the most accommodating. + */ + if ((request_mask & (STATX_DIOALIGN | STATX_DIO_READ_ALIGN)) && + S_ISREG(inode->i_mode)) { + stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN; + stat->dio_mem_align = 4; /* 4-byte alignment */ + stat->dio_offset_align = PAGE_SIZE; + stat->dio_read_offset_align = stat->dio_offset_align; + } out: trace_nfs_getattr_exit(inode, err); return err; |