diff options
Diffstat (limited to 'fs/cifs/transport.c')
| -rw-r--r-- | fs/cifs/transport.c | 41 |
1 files changed, 38 insertions, 3 deletions
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 9f23a4556131..7ce8a585abd6 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -33,6 +33,7 @@ #include <linux/uaccess.h> #include <asm/processor.h> #include <linux/mempool.h> +#include <linux/signal.h> #include "cifspdu.h" #include "cifsglob.h" #include "cifsproto.h" @@ -291,6 +292,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, int n_vec; unsigned int send_length = 0; unsigned int i, j; + sigset_t mask, oldmask; size_t total_len = 0, sent, size; struct socket *ssocket = server->ssocket; struct msghdr smb_msg; @@ -305,6 +307,11 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, if (ssocket == NULL) return -EAGAIN; + if (signal_pending(current)) { + cifs_dbg(FYI, "signal is pending before sending any data\n"); + return -EINTR; + } + /* cork the socket */ kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK, (char *)&val, sizeof(val)); @@ -313,6 +320,16 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, send_length += smb_rqst_len(server, &rqst[j]); rfc1002_marker = cpu_to_be32(send_length); + /* + * We should not allow signals to interrupt the network send because + * any partial send will cause session reconnects thus increasing + * latency of system calls and overload a server with unnecessary + * requests. + */ + + sigfillset(&mask); + sigprocmask(SIG_BLOCK, &mask, &oldmask); + /* Generate a rfc1002 marker for SMB2+ */ if (server->vals->header_preamble_size == 0) { struct kvec hiov = { @@ -322,7 +339,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, iov_iter_kvec(&smb_msg.msg_iter, WRITE, &hiov, 1, 4); rc = smb_send_kvec(server, &smb_msg, &sent); if (rc < 0) - goto uncork; + goto unmask; total_len += sent; send_length += 4; @@ -344,7 +361,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, rc = smb_send_kvec(server, &smb_msg, &sent); if (rc < 0) - goto uncork; + goto unmask; total_len += sent; @@ -366,7 +383,25 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst, } } -uncork: +unmask: + sigprocmask(SIG_SETMASK, &oldmask, NULL); + + /* + * If signal is pending but we have already sent the whole packet to + * the server we need to return success status to allow a corresponding + * mid entry to be kept in the pending requests queue thus allowing + * to handle responses from the server by the client. + * + * If only part of the packet has been sent there is no need to hide + * interrupt because the session will be reconnected anyway, so there + * won't be any response from the server to handle. + */ + + if (signal_pending(current) && (total_len != send_length)) { + cifs_dbg(FYI, "signal is pending after attempt to send\n"); + rc = -EINTR; + } + /* uncork it */ val = 0; kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK, |