On 4/12/2022 6:58 PM, Namjae Jeon wrote:
Currently ksmbd is using ->f_bsize from vfs_statfs() as sector size.
If fat/exfat is a local share, ->f_bsize is a cluster size that is too
large to be used as a sector size. Sector sizes larger than 4K cause
problem occurs when mounting an iso file through windows client.
The error message can be obtained using Mount-DiskImage command,
the error is:
"Mount-DiskImage : The sector size of the physical disk on which the
virtual disk resides is not supported."
This patch reports fixed sector size as 512B logical/4K physical to
windows client to avoid poking into the block device.
Cc: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
---
fs/ksmbd/smb2pdu.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 62cc0f95ab87..28ff7c058bc4 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -4998,12 +4998,11 @@ static int smb2_get_info_filesystem(struct ksmbd_work *work,
info = (struct smb3_fs_ss_info *)(rsp->Buffer);
- info->LogicalBytesPerSector = cpu_to_le32(stfs.f_bsize);
- info->PhysicalBytesPerSectorForAtomicity =
- cpu_to_le32(stfs.f_bsize);
- info->PhysicalBytesPerSectorForPerf = cpu_to_le32(stfs.f_bsize);
+ info->LogicalBytesPerSector = cpu_to_le32(512);
+ info->PhysicalBytesPerSectorForAtomicity = cpu_to_le32(4096);
+ info->PhysicalBytesPerSectorForPerf = cpu_to_le32(4096);
info->FSEffPhysicalBytesPerSectorForAtomicity =
- cpu_to_le32(stfs.f_bsize);
+ cpu_to_le32(4096);
So, this sounds like a great approach, much better than returning 128K.
However, it's not at all universally true that 4K is going to be atomic.
And min(stfs.f_bsize, 4096) might be problematic too. Is there any better
option??
Tom.
info->Flags = cpu_to_le32(SSINFO_FLAGS_ALIGNED_DEVICE |
SSINFO_FLAGS_PARTITION_ALIGNED_ON_DEVICE);
info->ByteOffsetForSectorAlignment = 0;
