Hi Steve, Al, Christoph,
Here's an updated version of a subset of my branch to make the cifs/smb3
driver pass iov_iters down to the lowest layers where they can be passed to
the network transport.
Al, Christoph: Could you look at the first four patches and see if you're okay
with them - at least on a temporary basis so that I can get this moving?
Note that patch (4) uses kmap_local_folio() to map an entire folio - this is
wrong. I'm going to try using Willy's vmap_folio() code - but I haven't done
that yet.
The first two patches are placed in netfslib as I have patches for netfslib
that will want to use them:
(1) Add a function to extract part of an IOVEC-/UBUF-type iterator into a
BVEC-type iterator. Refs are taken on the pages to prevent them from
evaporating.
(2) Add a function to extract part of an iterator into a scatterlist. If
extracting from an IOVEC-/UBUF-type iterator, the pages have refs taken on
them; any other type and they don't.
It might be worth splitting this into two separate functions, one for
IOVEC/UBUF that refs and one for the others that doesn't.
The other patches are placed in cifs as they're only used by cifs for now.
(3) Add a function to build an RDMA SGE list from a BVEC-, KVEC- or
XARRAY-type iterator. It's left to the caller to make sure they don't
evaporate.
(4) Add a function to hash part of the contents of a BVEC-, KVEC- or
XARRAY-type iterator.
I will need to make use of thew proposed page pinning when it becomes
available, but that's not yet.
Changes made in a later patch in the series make the upper layers convert an
IOVEC-/UBUF-iterator to a BVEC-type iterator in direct/unbuffered I/O so that
the signing, crypt and RDMA code see the BVEC instead of user buffers.
Note also that I haven't managed to test all the combinations of transport.
Samba doesn't support RDMA and ksmbd doesn't support encryption. I can test
them separately, but not together. That said, rdma, sign, seal and sign+seal
seem to work.
I've pushed the patches here also:
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=cifs-for-viro
David
---
David Howells (9):
netfs: Add a function to extract a UBUF or IOVEC into a BVEC iterator
netfs: Add a function to extract an iterator into a scatterlist
cifs: Add a function to build an RDMA SGE list from an iterator
cifs: Add a function to Hash the contents of an iterator
cifs: Add some helper functions
cifs: Add a function to read into an iter from a socket
cifs: Change the I/O paths to use an iterator rather than a page list
cifs: Build the RDMA SGE list directly from an iterator
cifs: Remove unused code
fs/cifs/cifsencrypt.c | 167 +++-
fs/cifs/cifsfs.h | 3 +
fs/cifs/cifsglob.h | 30 +-
fs/cifs/cifsproto.h | 11 +-
fs/cifs/cifssmb.c | 13 +-
fs/cifs/connect.c | 16 +
fs/cifs/file.c | 1700 ++++++++++++++++++-----------------------
fs/cifs/fscache.c | 22 +-
fs/cifs/fscache.h | 10 +-
fs/cifs/misc.c | 110 +--
fs/cifs/smb2ops.c | 378 +++++----
fs/cifs/smb2pdu.c | 44 +-
fs/cifs/smbdirect.c | 503 +++++++-----
fs/cifs/smbdirect.h | 4 +-
fs/cifs/transport.c | 57 +-
fs/netfs/Makefile | 1 +
fs/netfs/iterator.c | 347 +++++++++
include/linux/netfs.h | 5 +
18 files changed, 1835 insertions(+), 1586 deletions(-)
create mode 100644 fs/netfs/iterator.c
