[PATCH AUTOSEL 4.19 041/100] cifs: add credits from unmatched responses/messages

From: Sasha Levin
Date: Fri Oct 18 2019 - 18:21:04 EST


From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>

[ Upstream commit eca004523811f816bcfca3046ab54e1278e0973b ]

We should add any credits granted to us from unmatched server responses.

Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Reviewed-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/cifs/connect.c | 22 ++++++++++++++++++++++
fs/cifs/smb2misc.c | 7 -------
2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 966e493c82e57..7e85070d010f4 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -930,6 +930,26 @@ cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
return 0;
}

+static void
+smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
+{
+ struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
+
+ /*
+ * SMB1 does not use credits.
+ */
+ if (server->vals->header_preamble_size)
+ return;
+
+ if (shdr->CreditRequest) {
+ spin_lock(&server->req_lock);
+ server->credits += le16_to_cpu(shdr->CreditRequest);
+ spin_unlock(&server->req_lock);
+ wake_up(&server->request_q);
+ }
+}
+
+
static int
cifs_demultiplex_thread(void *p)
{
@@ -1059,6 +1079,7 @@ cifs_demultiplex_thread(void *p)
} else if (server->ops->is_oplock_break &&
server->ops->is_oplock_break(bufs[i],
server)) {
+ smb2_add_credits_from_hdr(bufs[i], server);
cifs_dbg(FYI, "Received oplock break\n");
} else {
cifs_dbg(VFS, "No task to wake, unknown frame "
@@ -1070,6 +1091,7 @@ cifs_demultiplex_thread(void *p)
if (server->ops->dump_detail)
server->ops->dump_detail(bufs[i],
server);
+ smb2_add_credits_from_hdr(bufs[i], server);
cifs_dump_mids(server);
#endif /* CIFS_DEBUG2 */
}
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 0a7ed2e3ad4f2..e311f58dc1c82 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -659,13 +659,6 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
return false;

- if (rsp->sync_hdr.CreditRequest) {
- spin_lock(&server->req_lock);
- server->credits += le16_to_cpu(rsp->sync_hdr.CreditRequest);
- spin_unlock(&server->req_lock);
- wake_up(&server->request_q);
- }
-
if (rsp->StructureSize !=
smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
if (le16_to_cpu(rsp->StructureSize) == 44)
--
2.20.1