diff options
| author | Long Li <longli@microsoft.com> | 2017-11-23 03:38:47 +0300 |
|---|---|---|
| committer | Steve French <smfrench@gmail.com> | 2018-01-25 04:49:07 +0300 |
| commit | bd3dcc6a22a9186ed78da51ce09e889803552189 (patch) | |
| tree | f334b0f07c9789530c971464426ac6208ec2582d /fs/cifs/file.c | |
| parent | 74dcf418fe344657b0e48a5a4b75f935443fa53f (diff) | |
| download | linux-bd3dcc6a22a9186ed78da51ce09e889803552189.tar.xz | |
CIFS: SMBD: Upper layer performs SMB read via RDMA write through memory registration
If I/O size is larger than rdma_readwrite_threshold, use RDMA write for
SMB read by specifying channel SMB2_CHANNEL_RDMA_V1 or
SMB2_CHANNEL_RDMA_V1_INVALIDATE in the SMB packet, depending on SMB dialect
used. Append a smbd_buffer_descriptor_v1 to the end of the SMB packet and fill
in other values to indicate this SMB read uses RDMA write.
There is no need to read from the transport for incoming payload. At the time
SMB read response comes back, the data is already transferred and placed in the
pages by RDMA hardware.
When SMB read is finished, deregister the memory regions if RDMA write is used
for this SMB read. smbd_deregister_mr may need to do local invalidation and
sleep, if server remote invalidation is not used.
There are situations where the MID may not be created on I/O failure, under
which memory region is deregistered when read data context is released.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Diffstat (limited to 'fs/cifs/file.c')
| -rw-r--r-- | fs/cifs/file.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 3a85df2a9baf..7cee97b93a61 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -42,7 +42,7 @@ #include "cifs_debug.h" #include "cifs_fs_sb.h" #include "fscache.h" - +#include "smbdirect.h" static inline int cifs_convert_flags(unsigned int flags) { @@ -2902,7 +2902,12 @@ cifs_readdata_release(struct kref *refcount) { struct cifs_readdata *rdata = container_of(refcount, struct cifs_readdata, refcount); - +#ifdef CONFIG_CIFS_SMB_DIRECT + if (rdata->mr) { + smbd_deregister_mr(rdata->mr); + rdata->mr = NULL; + } +#endif if (rdata->cfile) cifsFileInfo_put(rdata->cfile); @@ -3031,6 +3036,10 @@ uncached_fill_pages(struct TCP_Server_Info *server, } if (iter) result = copy_page_from_iter(page, 0, n, iter); +#ifdef CONFIG_CIFS_SMB_DIRECT + else if (rdata->mr) + result = n; +#endif else result = cifs_read_page_from_socket(server, page, n); if (result < 0) @@ -3598,6 +3607,10 @@ readpages_fill_pages(struct TCP_Server_Info *server, if (iter) result = copy_page_from_iter(page, 0, n, iter); +#ifdef CONFIG_CIFS_SMB_DIRECT + else if (rdata->mr) + result = n; +#endif else result = cifs_read_page_from_socket(server, page, n); if (result < 0) |