On 5/23/2024 2:36 AM, David Howells wrote:
ronnie sahlberg <ronniesahlberg@xxxxxxxxx> wrote:
The problem is that it essentially renders SEEK_DATA/SEEK_HOLE unusable for
applications on cifs. If there's more than one extent above the starting
position, they'll fail with EIO. The only way to do it is to provide for a
sufficiently large buffer to accommodate however many extents that there are
(and there could be millions, in theory) in order to get just the first one.
Wait, I didn't read all the text in the initial posts correctly.
Do you mean if you ask for "max x bytes of response, enough for n
entries" then if there
are > n entries on the server you get nothing back?
I am pretty sure Windows will return as many entries as fits in the
reponse out-data-size
nad some error code.
But you are saying that instead of returning a truncated out-blob that > If OutputBufferSize < ((OutputBufferIndex + 1) *
sizeof(FILE_ALLOCATED_RANGE_BUFFER)) then:
Set Status to STATUS_BUFFER_OVERFLOW.
samba will return nothing?
It returns a STATUS_BUFFER_TOO_SMALL error if there's more than one extent
record to return.
Yeah, I think this is a Samba server issue. Ronnie is right that it
should return a partial response and a STATUS_BUFFER_OVERFLOW error
indicating that it's partial. It's not supposed to return
STATUS_BUFFER_TOO_SMALL unless the entire buffer is less than one
entry.
MS-FSA section 2.5.10.22
https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-fsa/385dec98-90fe-477f-9789-20a47a7b8467
Tom.
