From 14fbf50d695207754daeb96270b3027a3821121f Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 14 Nov 2008 13:53:46 -0500 Subject: cifs: reinstate sharing of SMB sessions sans races We do this by abandoning the global list of SMB sessions and instead moving to a per-server list. This entails adding a new list head to the TCP_Server_Info struct. The refcounting for the cifsSesInfo is moved to a non-atomic variable. We have to protect it by a lock anyway, so there's no benefit to making it an atomic. The list and refcount are protected by the global cifs_tcp_ses_lock. The patch also adds a new routines to find and put SMB sessions and that properly take and put references under the lock. Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/cifs_debug.c | 53 ++++++++++++++++++++++++++-------------------------- 1 file changed, 27 insertions(+), 26 deletions(-) (limited to 'fs/cifs/cifs_debug.c') diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c index 40b5108fb4f9..59841a68b0b6 100644 --- a/fs/cifs/cifs_debug.c +++ b/fs/cifs/cifs_debug.c @@ -107,9 +107,9 @@ void cifs_dump_mids(struct TCP_Server_Info *server) #ifdef CONFIG_PROC_FS static int cifs_debug_data_proc_show(struct seq_file *m, void *v) { - struct list_head *tmp; - struct list_head *tmp1; + struct list_head *tmp, *tmp2, *tmp3; struct mid_q_entry *mid_entry; + struct TCP_Server_Info *server; struct cifsSesInfo *ses; struct cifsTconInfo *tcon; int i; @@ -122,43 +122,45 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v) seq_printf(m, "Servers:"); i = 0; - read_lock(&GlobalSMBSeslock); - list_for_each(tmp, &GlobalSMBSessionList) { + read_lock(&cifs_tcp_ses_lock); + list_for_each(tmp, &cifs_tcp_ses_list) { + server = list_entry(tmp, struct TCP_Server_Info, + tcp_ses_list); i++; - ses = list_entry(tmp, struct cifsSesInfo, cifsSessionList); - if ((ses->serverDomain == NULL) || (ses->serverOS == NULL) || - (ses->serverNOS == NULL)) { - seq_printf(m, "\nentry for %s not fully " - "displayed\n\t", ses->serverName); - } else { - seq_printf(m, + list_for_each(tmp2, &server->smb_ses_list) { + ses = list_entry(tmp2, struct cifsSesInfo, + smb_ses_list); + if ((ses->serverDomain == NULL) || + (ses->serverOS == NULL) || + (ses->serverNOS == NULL)) { + seq_printf(m, "\nentry for %s not fully " + "displayed\n\t", ses->serverName); + } else { + seq_printf(m, "\n%d) Name: %s Domain: %s Mounts: %d OS:" " %s \n\tNOS: %s\tCapability: 0x%x\n\tSMB" " session status: %d\t", i, ses->serverName, ses->serverDomain, - atomic_read(&ses->inUse), - ses->serverOS, ses->serverNOS, + ses->ses_count, ses->serverOS, ses->serverNOS, ses->capabilities, ses->status); - } - if (ses->server) { + } seq_printf(m, "TCP status: %d\n\tLocal Users To " - "Server: %d SecMode: 0x%x Req On Wire: %d", - ses->server->tcpStatus, - ses->server->srv_count, - ses->server->secMode, - atomic_read(&ses->server->inFlight)); + "Server: %d SecMode: 0x%x Req On Wire: %d", + server->tcpStatus, server->srv_count, + server->secMode, + atomic_read(&server->inFlight)); #ifdef CONFIG_CIFS_STATS2 seq_printf(m, " In Send: %d In MaxReq Wait: %d", - atomic_read(&ses->server->inSend), - atomic_read(&ses->server->num_waiters)); + atomic_read(&server->inSend), + atomic_read(&server->num_waiters)); #endif seq_puts(m, "\nMIDs:\n"); spin_lock(&GlobalMid_Lock); - list_for_each(tmp1, &ses->server->pending_mid_q) { - mid_entry = list_entry(tmp1, struct + list_for_each(tmp3, &server->pending_mid_q) { + mid_entry = list_entry(tmp3, struct mid_q_entry, qhead); seq_printf(m, "State: %d com: %d pid:" @@ -171,9 +173,8 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v) } spin_unlock(&GlobalMid_Lock); } - } - read_unlock(&GlobalSMBSeslock); + read_unlock(&cifs_tcp_ses_lock); seq_putc(m, '\n'); seq_puts(m, "Shares:"); -- cgit v1.2.3