CIFS: Fix an issue with re-sending rdata when transport returning -EAGAIN

When sending a rdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
This commit is contained in:
Long Li 2019-03-15 07:55:00 +00:00 committed by Steve French
parent d53e292f0f
commit 0b0dfd5921
1 changed files with 41 additions and 30 deletions

View File

@ -3361,44 +3361,55 @@ static int cifs_resend_rdata(struct cifs_readdata *rdata,
struct TCP_Server_Info *server =
tlink_tcon(rdata->cfile->tlink)->ses->server;
do {
if (rdata->cfile->invalidHandle) {
rc = cifs_reopen_file(rdata->cfile, true);
if (rc == -EAGAIN)
continue;
else if (rc)
break;
}
/*
* Wait for credits to resend this rdata.
* Note: we are attempting to resend the whole rdata not in segments
* Note: we are attempting to resend the whole rdata not in
* segments
*/
do {
rc = server->ops->wait_mtu_credits(server, rdata->bytes,
&rsize, &credits);
if (rc)
goto out;
goto fail;
if (rsize < rdata->bytes) {
add_credits_and_wake_if(server, &credits, 0);
msleep(1000);
}
} while (rsize < rdata->bytes);
rdata->credits = credits;
rc = -EAGAIN;
while (rc == -EAGAIN) {
rc = 0;
rc = adjust_credits(server, &rdata->credits, rdata->bytes);
if (!rc) {
if (rdata->cfile->invalidHandle)
rc = cifs_reopen_file(rdata->cfile, true);
if (!rc)
rc = -EAGAIN;
else
rc = server->ops->async_readv(rdata);
}
/* If the read was successfully sent, we are done */
if (!rc) {
/* Add to aio pending list */
list_add_tail(&rdata->list, rdata_list);
return 0;
}
/* Roll back credits and retry if needed */
add_credits_and_wake_if(server, &rdata->credits, 0);
out:
kref_put(&rdata->refcount,
cifs_uncached_readdata_release);
} while (rc == -EAGAIN);
fail:
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
return rc;
}