net: nfs: add dynamic wait period

This patch tackles the time out problem which leads to break the
boot process, when loading file over nfs. The patch does two things.

First of all, we just ignore messages that arrive with a rpc_id smaller
then the client id. We just interpret this messages as answers to
formaly timed out messages.

Second, when a time out occurs we double the time to wait, so that we
do not stress the server resending the last message.

Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Tested-by: Enric Balletbo i Serra <eballetbo@gmail.com>

diff --git a/net/nfs.c b/net/nfs.c
index 7f2393f6064c62976ea3bf0c5f10a2ac22e7d443..381b75f1c5b091799876aa77ec8997c97ea14fa9 100644 (file)
--- a/net/nfs.c
+++ b/net/nfs.c
@@ -37,10 +37,14 @@
 # define NFS_TIMEOUT CONFIG_NFS_TIMEOUT
 #endif
 
+#define NFS_RPC_ERR    1
+#define NFS_RPC_DROP   124
+
 static int fs_mounted;
 static unsigned long rpc_id;
 static int nfs_offset = -1;
 static int nfs_len;
+static ulong nfs_timeout = NFS_TIMEOUT;
 
 static char dirfh[NFS_FHSIZE]; /* file handle of directory */
 static char filefh[NFS_FHSIZE]; /* file handle of kernel image */
@@ -399,8 +403,10 @@ rpc_lookup_reply(int prog, uchar *pkt, unsigned len)
 
        debug("%s\n", __func__);
 
-       if (ntohl(rpc_pkt.u.reply.id) != rpc_id)
-               return -1;
+       if (ntohl(rpc_pkt.u.reply.id) > rpc_id)
+               return -NFS_RPC_ERR;
+       else if (ntohl(rpc_pkt.u.reply.id) < rpc_id)
+               return -NFS_RPC_DROP;
 
        if (rpc_pkt.u.reply.rstatus  ||
            rpc_pkt.u.reply.verifier ||
@@ -428,8 +434,10 @@ nfs_mount_reply(uchar *pkt, unsigned len)
 
        memcpy((unsigned char *)&rpc_pkt, pkt, len);
 
-       if (ntohl(rpc_pkt.u.reply.id) != rpc_id)
-               return -1;
+       if (ntohl(rpc_pkt.u.reply.id) > rpc_id)
+               return -NFS_RPC_ERR;
+       else if (ntohl(rpc_pkt.u.reply.id) < rpc_id)
+               return -NFS_RPC_DROP;
 
        if (rpc_pkt.u.reply.rstatus  ||
            rpc_pkt.u.reply.verifier ||
@@ -452,8 +460,10 @@ nfs_umountall_reply(uchar *pkt, unsigned len)
 
        memcpy((unsigned char *)&rpc_pkt, pkt, len);
 
-       if (ntohl(rpc_pkt.u.reply.id) != rpc_id)
-               return -1;
+       if (ntohl(rpc_pkt.u.reply.id) > rpc_id)
+               return -NFS_RPC_ERR;
+       else if (ntohl(rpc_pkt.u.reply.id) < rpc_id)
+               return -NFS_RPC_DROP;
 
        if (rpc_pkt.u.reply.rstatus  ||
            rpc_pkt.u.reply.verifier ||
@@ -475,8 +485,10 @@ nfs_lookup_reply(uchar *pkt, unsigned len)
 
        memcpy((unsigned char *)&rpc_pkt, pkt, len);
 
-       if (ntohl(rpc_pkt.u.reply.id) != rpc_id)
-               return -1;
+       if (ntohl(rpc_pkt.u.reply.id) > rpc_id)
+               return -NFS_RPC_ERR;
+       else if (ntohl(rpc_pkt.u.reply.id) < rpc_id)
+               return -NFS_RPC_DROP;
 
        if (rpc_pkt.u.reply.rstatus  ||
            rpc_pkt.u.reply.verifier ||
@@ -499,8 +511,10 @@ nfs_readlink_reply(uchar *pkt, unsigned len)
 
        memcpy((unsigned char *)&rpc_pkt, pkt, len);
 
-       if (ntohl(rpc_pkt.u.reply.id) != rpc_id)
-               return -1;
+       if (ntohl(rpc_pkt.u.reply.id) > rpc_id)
+               return -NFS_RPC_ERR;
+       else if (ntohl(rpc_pkt.u.reply.id) < rpc_id)
+               return -NFS_RPC_DROP;
 
        if (rpc_pkt.u.reply.rstatus  ||
            rpc_pkt.u.reply.verifier ||
@@ -534,8 +548,10 @@ nfs_read_reply(uchar *pkt, unsigned len)
 
        memcpy((uchar *)&rpc_pkt, pkt, sizeof(rpc_pkt.u.reply));
 
-       if (ntohl(rpc_pkt.u.reply.id) != rpc_id)
-               return -1;
+       if (ntohl(rpc_pkt.u.reply.id) > rpc_id)
+               return -NFS_RPC_ERR;
+       else if (ntohl(rpc_pkt.u.reply.id) < rpc_id)
+               return -NFS_RPC_DROP;
 
        if (rpc_pkt.u.reply.rstatus  ||
            rpc_pkt.u.reply.verifier ||
@@ -574,7 +590,8 @@ NfsTimeout(void)
                NetStartAgain();
        } else {
                puts("T ");
-               NetSetTimeout(NFS_TIMEOUT, NfsTimeout);
+               NetSetTimeout(nfs_timeout + NFS_TIMEOUT * NfsTimeoutCount,
+                             NfsTimeout);
                NfsSend();
        }
 }
@@ -583,6 +600,7 @@ static void
 NfsHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src, unsigned len)
 {
        int rlen;
+       int reply;
 
        debug("%s\n", __func__);
 
@@ -591,19 +609,24 @@ NfsHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src, unsigned len)
 
        switch (NfsState) {
        case STATE_PRCLOOKUP_PROG_MOUNT_REQ:
-               rpc_lookup_reply(PROG_MOUNT, pkt, len);
+               if (rpc_lookup_reply(PROG_MOUNT, pkt, len) == -NFS_RPC_DROP)
+                       break;
                NfsState = STATE_PRCLOOKUP_PROG_NFS_REQ;
                NfsSend();
                break;
 
        case STATE_PRCLOOKUP_PROG_NFS_REQ:
-               rpc_lookup_reply(PROG_NFS, pkt, len);
+               if (rpc_lookup_reply(PROG_NFS, pkt, len) == -NFS_RPC_DROP)
+                       break;
                NfsState = STATE_MOUNT_REQ;
                NfsSend();
                break;
 
        case STATE_MOUNT_REQ:
-               if (nfs_mount_reply(pkt, len)) {
+               reply = nfs_mount_reply(pkt, len);
+               if (reply == -NFS_RPC_DROP)
+                       break;
+               else if (reply == -NFS_RPC_ERR) {
                        puts("*** ERROR: Cannot mount\n");
                        /* just to be sure... */
                        NfsState = STATE_UMOUNT_REQ;
@@ -615,7 +638,10 @@ NfsHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src, unsigned len)
                break;
 
        case STATE_UMOUNT_REQ:
-               if (nfs_umountall_reply(pkt, len)) {
+               reply = nfs_umountall_reply(pkt, len);
+               if (reply == -NFS_RPC_DROP)
+                       break;
+               else if (reply == -NFS_RPC_ERR) {
                        puts("*** ERROR: Cannot umount\n");
                        net_set_state(NETLOOP_FAIL);
                } else {
@@ -625,7 +651,10 @@ NfsHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src, unsigned len)
                break;
 
        case STATE_LOOKUP_REQ:
-               if (nfs_lookup_reply(pkt, len)) {
+               reply = nfs_lookup_reply(pkt, len);
+               if (reply == -NFS_RPC_DROP)
+                       break;
+               else if (reply == -NFS_RPC_ERR) {
                        puts("*** ERROR: File lookup fail\n");
                        NfsState = STATE_UMOUNT_REQ;
                        NfsSend();
@@ -638,7 +667,10 @@ NfsHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src, unsigned len)
                break;
 
        case STATE_READLINK_REQ:
-               if (nfs_readlink_reply(pkt, len)) {
+               reply = nfs_readlink_reply(pkt, len);
+               if (reply == -NFS_RPC_DROP)
+                       break;
+               else if (reply == -NFS_RPC_ERR) {
                        puts("*** ERROR: Symlink fail\n");
                        NfsState = STATE_UMOUNT_REQ;
                        NfsSend();
@@ -654,7 +686,7 @@ NfsHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src, unsigned len)
 
        case STATE_READ_REQ:
                rlen = nfs_read_reply(pkt, len);
-               NetSetTimeout(NFS_TIMEOUT, NfsTimeout);
+               NetSetTimeout(nfs_timeout, NfsTimeout);
                if (rlen > 0) {
                        nfs_offset += rlen;
                        NfsSend();
@@ -738,7 +770,7 @@ NfsStart(void)
        printf("\nLoad address: 0x%lx\n"
                "Loading: *\b", load_addr);
 
-       NetSetTimeout(NFS_TIMEOUT, NfsTimeout);
+       NetSetTimeout(nfs_timeout, NfsTimeout);
        net_set_udp_handler(NfsHandler);
 
        NfsTimeoutCount = 0;