From ddc8cf8fc718587a3788330bf4f32b379f08b250 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Tue, 11 Jan 2011 07:24:02 -0500 Subject: [PATCH] cifs: move locked sections out of DeleteMidQEntry and AllocMidQEntry In later patches, we're going to need to have finer-grained control over the addition and removal of these structs from the pending_mid_q and we'll need to be able to call the destructor while holding the spinlock. Move the locked sections out of both routines and into the callers. Fix up current callers of DeleteMidQEntry to call a new routine that dequeues the entry and then destroys it. Reviewed-by: Suresh Jayaraman Reviewed-by: Pavel Shilovsky Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/transport.c | 41 ++++++++++++++++++++++++----------------- 1 file changed, 24 insertions(+), 17 deletions(-) diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index b9eb0cffa003..801726b11e1e 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -63,9 +63,6 @@ AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server) atomic_inc(&midCount); temp->midState = MID_REQUEST_ALLOCATED; - spin_lock(&GlobalMid_Lock); - list_add_tail(&temp->qhead, &server->pending_mid_q); - spin_unlock(&GlobalMid_Lock); return temp; } @@ -75,10 +72,7 @@ DeleteMidQEntry(struct mid_q_entry *midEntry) #ifdef CONFIG_CIFS_STATS2 unsigned long now; #endif - spin_lock(&GlobalMid_Lock); midEntry->midState = MID_FREE; - list_del(&midEntry->qhead); - spin_unlock(&GlobalMid_Lock); atomic_dec(&midCount); if (midEntry->largeBuf) cifs_buf_release(midEntry->resp_buf); @@ -103,6 +97,16 @@ DeleteMidQEntry(struct mid_q_entry *midEntry) mempool_free(midEntry, cifs_mid_poolp); } +static void +delete_mid(struct mid_q_entry *mid) +{ + spin_lock(&GlobalMid_Lock); + list_del(&mid->qhead); + spin_unlock(&GlobalMid_Lock); + + DeleteMidQEntry(mid); +} + static int smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) { @@ -308,6 +312,9 @@ static int allocate_mid(struct cifsSesInfo *ses, struct smb_hdr *in_buf, *ppmidQ = AllocMidQEntry(in_buf, ses->server); if (*ppmidQ == NULL) return -ENOMEM; + spin_lock(&GlobalMid_Lock); + list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q); + spin_unlock(&GlobalMid_Lock); return 0; } @@ -508,7 +515,7 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, } } spin_unlock(&GlobalMid_Lock); - DeleteMidQEntry(midQ); + delete_mid(midQ); /* Update # of requests on wire to server */ atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); @@ -564,14 +571,14 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, if ((flags & CIFS_NO_RESP) == 0) midQ->resp_buf = NULL; /* mark it so buf will not be freed by - DeleteMidQEntry */ + delete_mid */ } else { rc = -EIO; cFYI(1, "Bad MID state?"); } out: - DeleteMidQEntry(midQ); + delete_mid(midQ); atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); @@ -699,7 +706,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses, } } spin_unlock(&GlobalMid_Lock); - DeleteMidQEntry(midQ); + delete_mid(midQ); /* Update # of requests on wire to server */ atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); @@ -755,7 +762,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses, } out: - DeleteMidQEntry(midQ); + delete_mid(midQ); atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); @@ -863,7 +870,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); if (rc) { - DeleteMidQEntry(midQ); + delete_mid(midQ); mutex_unlock(&ses->server->srv_mutex); return rc; } @@ -880,7 +887,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, mutex_unlock(&ses->server->srv_mutex); if (rc < 0) { - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } @@ -902,7 +909,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, rc = send_nt_cancel(tcon, in_buf, midQ); if (rc) { - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } } else { @@ -914,7 +921,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, /* If we get -ENOLCK back the lock may have already been removed. Don't exit in this case. */ if (rc && rc != -ENOLCK) { - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } } @@ -951,7 +958,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, } } spin_unlock(&GlobalMid_Lock); - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } @@ -1001,7 +1008,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, BCC(out_buf) = le16_to_cpu(BCC_LE(out_buf)); out: - DeleteMidQEntry(midQ); + delete_mid(midQ); if (rstart && rc == -EACCES) return -ERESTARTSYS; return rc; -- 2.20.1