diff options
| author | Hannes Reinecke <hare@suse.de> | 2016-05-24 08:11:58 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2016-07-12 23:16:31 -0400 |
| commit | baa6719f902af9c03e528b08dfb847de295b5137 (patch) | |
| tree | 8ac928054932e15da8feaa5a60b7385ab0787958 /drivers/scsi/libfc/fc_lport.c | |
| parent | 7e1ee4412ca35b17e21159d85224e37e8f259311 (diff) | |
| download | linux-baa6719f902af9c03e528b08dfb847de295b5137.tar.bz2 | |
libfc: Update rport reference counting
Originally libfc would just be initializing the refcount to '1', and
using the disc_mutex to synchronize if and when the final put should be
happening. This has a race condition as the mutex might be delayed,
causing other threads to access an invalid structure. This patch
updates the rport reference counting to increase the reference every
time 'rport_lookup' is called, and decreases the reference
correspondingly. This removes the need to hold 'disc_mutex' when
removing the structure, and avoids the above race condition.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Acked-by: Vasu Dev <vasu.dev@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/libfc/fc_lport.c')
| -rw-r--r-- | drivers/scsi/libfc/fc_lport.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/drivers/scsi/libfc/fc_lport.c b/drivers/scsi/libfc/fc_lport.c index e01a29863c38..b9b44daff159 100644 --- a/drivers/scsi/libfc/fc_lport.c +++ b/drivers/scsi/libfc/fc_lport.c @@ -2090,7 +2090,7 @@ int fc_lport_bsg_request(struct fc_bsg_job *job) struct fc_rport *rport; struct fc_rport_priv *rdata; int rc = -EINVAL; - u32 did; + u32 did, tov; job->reply->reply_payload_rcv_len = 0; if (rsp) @@ -2121,15 +2121,20 @@ int fc_lport_bsg_request(struct fc_bsg_job *job) case FC_BSG_HST_CT: did = ntoh24(job->request->rqst_data.h_ct.port_id); - if (did == FC_FID_DIR_SERV) + if (did == FC_FID_DIR_SERV) { rdata = lport->dns_rdata; - else + if (!rdata) + break; + tov = rdata->e_d_tov; + } else { rdata = lport->tt.rport_lookup(lport, did); + if (!rdata) + break; + tov = rdata->e_d_tov; + kref_put(&rdata->kref, lport->tt.rport_destroy); + } - if (!rdata) - break; - - rc = fc_lport_ct_request(job, lport, did, rdata->e_d_tov); + rc = fc_lport_ct_request(job, lport, did, tov); break; case FC_BSG_HST_ELS_NOLOGIN: |