From: Tom Talpey <tom@talpey.com>
Date: Fri, 23 Sep 2022 21:53:59 +0000
Subject: [PATCH] Handle variable number of SGEs in client smbdirect send.
Git-commit: adeb964d3791e1eea8c4c3ab13549ccc7e411e07
References: bsc#1190317
Patch-mainline: v6.1-rc1
If/when an outgoing request contains more scatter/gather segments
than can be mapped in a single RDMA send work request, use smbdirect
fragments to send it in multiple packets.
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/smbdirect.c | 196 ++++++++++++++++++++--------------------------------
1 file changed, 78 insertions(+), 118 deletions(-)
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -1992,10 +1992,11 @@ int smbd_send(struct TCP_Server_Info *se
int num_rqst, struct smb_rqst *rqst_array)
{
struct smbd_connection *info = server->smbd_conn;
- struct kvec vec;
+ struct kvec vecs[SMBDIRECT_MAX_SEND_SGE - 1];
int nvecs;
int size;
unsigned int buflen, remaining_data_length;
+ unsigned int offset, remaining_vec_data_length;
int start, i, j;
int max_iov_size =
info->max_send_size - sizeof(struct smbd_data_transfer);
@@ -2004,10 +2005,8 @@ int smbd_send(struct TCP_Server_Info *se
struct smb_rqst *rqst;
int rqst_idx;
- if (info->transport_status != SMBD_CONNECTED) {
- rc = -EAGAIN;
- goto done;
- }
+ if (info->transport_status != SMBD_CONNECTED)
+ return -EAGAIN;
/*
* Add in the page array if there is one. The caller needs to set
@@ -2018,134 +2017,95 @@ int smbd_send(struct TCP_Server_Info *se
for (i = 0; i < num_rqst; i++)
remaining_data_length += smb_rqst_len(server, &rqst_array[i]);
- if (remaining_data_length > info->max_fragmented_send_size) {
+ if (unlikely(remaining_data_length > info->max_fragmented_send_size)) {
+ /* assertion: payload never exceeds negotiated maximum */
log_write(ERR, "payload size %d > max size %d\n",
remaining_data_length, info->max_fragmented_send_size);
- rc = -EINVAL;
- goto done;
+ return -EINVAL;
}
log_write(INFO, "num_rqst=%d total length=%u\n",
num_rqst, remaining_data_length);
rqst_idx = 0;
-next_rqst:
- rqst = &rqst_array[rqst_idx];
- iov = rqst->rq_iov;
-
- cifs_dbg(FYI, "Sending smb (RDMA): idx=%d smb_len=%lu\n",
- rqst_idx, smb_rqst_len(server, rqst));
- for (i = 0; i < rqst->rq_nvec; i++)
- dump_smb(iov[i].iov_base, iov[i].iov_len);
-
-
- log_write(INFO, "rqst_idx=%d nvec=%d rqst->rq_npages=%d rq_pagesz=%d "
- "rq_tailsz=%d buflen=%lu\n",
- rqst_idx, rqst->rq_nvec, rqst->rq_npages, rqst->rq_pagesz,
- rqst->rq_tailsz, smb_rqst_len(server, rqst));
-
- start = i = 0;
- buflen = 0;
- while (true) {
- buflen += iov[i].iov_len;
- if (buflen > max_iov_size) {
- if (i > start) {
- remaining_data_length -=
- (buflen-iov[i].iov_len);
- log_write(INFO, "sending iov[] from start=%d "
- "i=%d nvecs=%d "
- "remaining_data_length=%d\n",
- start, i, i-start,
- remaining_data_length);
- rc = smbd_post_send_data(
- info, &iov[start], i-start,
- remaining_data_length);
- if (rc)
- goto done;
- } else {
- /* iov[start] is too big, break it */
- nvecs = (buflen+max_iov_size-1)/max_iov_size;
- log_write(INFO, "iov[%d] iov_base=%p buflen=%d"
- " break to %d vectors\n",
- start, iov[start].iov_base,
- buflen, nvecs);
- for (j = 0; j < nvecs; j++) {
- vec.iov_base =
- (char *)iov[start].iov_base +
- j*max_iov_size;
- vec.iov_len = max_iov_size;
- if (j == nvecs-1)
- vec.iov_len =
- buflen -
- max_iov_size*(nvecs-1);
- remaining_data_length -= vec.iov_len;
- log_write(INFO,
- "sending vec j=%d iov_base=%p"
- " iov_len=%zu "
- "remaining_data_length=%d\n",
- j, vec.iov_base, vec.iov_len,
- remaining_data_length);
- rc = smbd_post_send_data(
- info, &vec, 1,
- remaining_data_length);
- if (rc)
- goto done;
+ do {
+ rqst = &rqst_array[rqst_idx];
+ iov = rqst->rq_iov;
+
+ cifs_dbg(FYI, "Sending smb (RDMA): idx=%d smb_len=%lu\n",
+ rqst_idx, smb_rqst_len(server, rqst));
+ remaining_vec_data_length = 0;
+ for (i = 0; i < rqst->rq_nvec; i++) {
+ remaining_vec_data_length += iov[i].iov_len;
+ dump_smb(iov[i].iov_base, iov[i].iov_len);
+ }
+
+ log_write(INFO, "rqst_idx=%d nvec=%d rqst->rq_npages=%d rq_pagesz=%d rq_tailsz=%d buflen=%lu\n",
+ rqst_idx, rqst->rq_nvec,
+ rqst->rq_npages, rqst->rq_pagesz,
+ rqst->rq_tailsz, smb_rqst_len(server, rqst));
+
+ start = 0;
+ offset = 0;
+ do {
+ buflen = 0;
+ i = start;
+ j = 0;
+ while (i < rqst->rq_nvec &&
+ j < SMBDIRECT_MAX_SEND_SGE - 1 &&
+ buflen < max_iov_size) {
+
+ vecs[j].iov_base = iov[i].iov_base + offset;
+ if (buflen + iov[i].iov_len > max_iov_size) {
+ vecs[j].iov_len =
+ max_iov_size - iov[i].iov_len;
+ buflen = max_iov_size;
+ offset = vecs[j].iov_len;
+ } else {
+ vecs[j].iov_len =
+ iov[i].iov_len - offset;
+ buflen += vecs[j].iov_len;
+ offset = 0;
+ ++i;
}
- i++;
- if (i == rqst->rq_nvec)
- break;
+ ++j;
}
- start = i;
- buflen = 0;
- } else {
- i++;
- if (i == rqst->rq_nvec) {
- /* send out all remaining vecs */
- remaining_data_length -= buflen;
- log_write(INFO,
- "sending iov[] from start=%d i=%d "
- "nvecs=%d remaining_data_length=%d\n",
- start, i, i-start,
+
+ remaining_vec_data_length -= buflen;
+ remaining_data_length -= buflen;
+ log_write(INFO, "sending %s iov[%d] from start=%d nvecs=%d remaining_data_length=%d\n",
+ remaining_vec_data_length > 0 ?
+ "partial" : "complete",
+ rqst->rq_nvec, start, j,
remaining_data_length);
- rc = smbd_post_send_data(info, &iov[start],
- i-start, remaining_data_length);
- if (rc)
- goto done;
- break;
- }
- }
- log_write(INFO, "looping i=%d buflen=%d\n", i, buflen);
- }
- /* now sending pages if there are any */
- for (i = 0; i < rqst->rq_npages; i++) {
- unsigned int offset;
-
- rqst_page_get_length(rqst, i, &buflen, &offset);
- nvecs = (buflen + max_iov_size - 1) / max_iov_size;
- log_write(INFO, "sending pages buflen=%d nvecs=%d\n",
- buflen, nvecs);
- for (j = 0; j < nvecs; j++) {
- size = max_iov_size;
- if (j == nvecs-1)
- size = buflen - j*max_iov_size;
- remaining_data_length -= size;
- log_write(INFO, "sending pages i=%d offset=%d size=%d"
- " remaining_data_length=%d\n",
- i, j*max_iov_size+offset, size,
- remaining_data_length);
- rc = smbd_post_send_page(
- info, rqst->rq_pages[i],
- j*max_iov_size + offset,
- size, remaining_data_length);
+ start = i;
+ rc = smbd_post_send_data(info, vecs, j, remaining_data_length);
if (rc)
goto done;
- }
- }
+ } while (remaining_vec_data_length > 0);
- rqst_idx++;
- if (rqst_idx < num_rqst)
- goto next_rqst;
+ /* now sending pages if there are any */
+ for (i = 0; i < rqst->rq_npages; i++) {
+ rqst_page_get_length(rqst, i, &buflen, &offset);
+ nvecs = (buflen + max_iov_size - 1) / max_iov_size;
+ log_write(INFO, "sending pages buflen=%d nvecs=%d\n",
+ buflen, nvecs);
+ for (j = 0; j < nvecs; j++) {
+ size = min_t(unsigned int, max_iov_size, remaining_data_length);
+ remaining_data_length -= size;
+ log_write(INFO, "sending pages i=%d offset=%d size=%d remaining_data_length=%d\n",
+ i, j * max_iov_size + offset, size,
+ remaining_data_length);
+ rc = smbd_post_send_page(
+ info, rqst->rq_pages[i],
+ j*max_iov_size + offset,
+ size, remaining_data_length);
+ if (rc)
+ goto done;
+ }
+ }
+ } while (++rqst_idx < num_rqst);
done:
/*