From 6f63caae2172e97e528b58319480217b0b36542e Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 26 Jan 2007 14:08:43 -0800 Subject: [PATCH] [SCSI] libsas: Clean up discovery failure handler code sas_rphy_delete does two things: it removes the sas_rphy from the transport layer and frees the sas_rphy. This can be broken down into two functions, sas_rphy_remove and sas_rphy_free; sas_rphy_remove is of interest to sas_discover_root_expander because it calls functions that require sas_rphy_add as a prerequisite and can fail (namely sas_discover_expander). In that case, sas_discover_root_expander needs to be able to undo the effects of sas_rphy_add yet leave the job of freeing the sas_rphy to the caller of sas_discover_root_expander. This patch also removes some unnecessary code from sas_discover_end_dev to eliminate an unnecessary cycle of sas_notify_lldd_gone/found for SAS devices, thus eliminating a sas_rphy_remove call (and fixing a race condition where a SCSI target scan can come in between the gone and found call). It also moves the sas_rphy_free calls into sas_discover_domain and sas_ex_discover_end_dev to complement the sas_rphy_allocation via sas_get_port_device. This patch does not change the semantics of sas_rphy_delete. Signed-off-by: Darrick J. Wong Signed-off-by: James Bottomley --- drivers/scsi/libsas/sas_discover.c | 45 +++++++++++------------------- drivers/scsi/libsas/sas_expander.c | 8 ++---- drivers/scsi/scsi_transport_sas.c | 33 ++++++++++++---------- include/scsi/scsi_transport_sas.h | 1 + 4 files changed, 40 insertions(+), 47 deletions(-) diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c index b6ba0e053d1a..a65598b1e536 100644 --- a/drivers/scsi/libsas/sas_discover.c +++ b/drivers/scsi/libsas/sas_discover.c @@ -577,8 +577,6 @@ int sas_discover_sata(struct domain_device *dev) out_err: sas_notify_lldd_dev_gone(dev); out_err2: - sas_rphy_free(dev->rphy); - dev->rphy = NULL; return res; } @@ -600,24 +598,11 @@ int sas_discover_end_dev(struct domain_device *dev) if (res) goto out_err; - /* do this to get the end device port attributes which will have - * been scanned in sas_rphy_add */ - sas_notify_lldd_dev_gone(dev); - res = sas_notify_lldd_dev_found(dev); - if (res) - goto out_err3; - return 0; out_err: sas_notify_lldd_dev_gone(dev); out_err2: - sas_rphy_free(dev->rphy); - dev->rphy = NULL; - return res; -out_err3: - sas_rphy_delete(dev->rphy); - dev->rphy = NULL; return res; } @@ -672,6 +657,7 @@ void sas_unregister_domain_devices(struct asd_sas_port *port) */ static void sas_discover_domain(struct work_struct *work) { + struct domain_device *dev; int error = 0; struct sas_discovery_event *ev = container_of(work, struct sas_discovery_event, work); @@ -681,39 +667,42 @@ static void sas_discover_domain(struct work_struct *work) &port->disc.pending); if (port->port_dev) - return ; - else { - error = sas_get_port_device(port); - if (error) - return; - } + return; + + error = sas_get_port_device(port); + if (error) + return; + dev = port->port_dev; SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id, current->pid); - switch (port->port_dev->dev_type) { + switch (dev->dev_type) { case SAS_END_DEV: - error = sas_discover_end_dev(port->port_dev); + error = sas_discover_end_dev(dev); break; case EDGE_DEV: case FANOUT_DEV: - error = sas_discover_root_expander(port->port_dev); + error = sas_discover_root_expander(dev); break; case SATA_DEV: case SATA_PM: - error = sas_discover_sata(port->port_dev); + error = sas_discover_sata(dev); break; default: - SAS_DPRINTK("unhandled device %d\n", port->port_dev->dev_type); + SAS_DPRINTK("unhandled device %d\n", dev->dev_type); break; } if (error) { + sas_rphy_free(dev->rphy); + dev->rphy = NULL; + spin_lock(&port->dev_list_lock); - list_del_init(&port->port_dev->dev_list_node); + list_del_init(&dev->dev_list_node); spin_unlock(&port->dev_list_lock); - kfree(port->port_dev); /* not kobject_register-ed yet */ + kfree(dev); /* not kobject_register-ed yet */ port->port_dev = NULL; } diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c index 0dfd97e7e96c..d9b9a008d36d 100644 --- a/drivers/scsi/libsas/sas_expander.c +++ b/drivers/scsi/libsas/sas_expander.c @@ -667,6 +667,8 @@ static struct domain_device *sas_ex_discover_end_dev( return child; out_list_del: + sas_rphy_free(child->rphy); + child->rphy = NULL; list_del(&child->dev_list_node); out_free: sas_port_delete(phy->port); @@ -1444,12 +1446,8 @@ int sas_discover_root_expander(struct domain_device *dev) return res; out_err2: - sas_rphy_delete(dev->rphy); - dev->rphy = NULL; - return res; + sas_rphy_remove(dev->rphy); out_err: - sas_rphy_free(dev->rphy); - dev->rphy = NULL; return res; } diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index ce232803f433..010845fd2b85 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -1299,7 +1299,7 @@ EXPORT_SYMBOL(sas_rphy_add); * Note: * This function must only be called on a remote * PHY that has not sucessfully been added using - * sas_rphy_add(). + * sas_rphy_add() (or has been sas_rphy_remove()'d) */ void sas_rphy_free(struct sas_rphy *rphy) { @@ -1318,18 +1318,30 @@ void sas_rphy_free(struct sas_rphy *rphy) EXPORT_SYMBOL(sas_rphy_free); /** - * sas_rphy_delete -- remove SAS remote PHY - * @rphy: SAS remote PHY to remove + * sas_rphy_delete -- remove and free SAS remote PHY + * @rphy: SAS remote PHY to remove and free * - * Removes the specified SAS remote PHY. + * Removes the specified SAS remote PHY and frees it. */ void sas_rphy_delete(struct sas_rphy *rphy) +{ + sas_rphy_remove(rphy); + sas_rphy_free(rphy); +} +EXPORT_SYMBOL(sas_rphy_delete); + +/** + * sas_rphy_remove -- remove SAS remote PHY + * @rphy: SAS remote phy to remove + * + * Removes the specified SAS remote PHY. + */ +void +sas_rphy_remove(struct sas_rphy *rphy) { struct device *dev = &rphy->dev; struct sas_port *parent = dev_to_sas_port(dev->parent); - struct Scsi_Host *shost = dev_to_shost(parent->dev.parent); - struct sas_host_attrs *sas_host = to_sas_host_attrs(shost); switch (rphy->identify.device_type) { case SAS_END_DEVICE: @@ -1345,17 +1357,10 @@ sas_rphy_delete(struct sas_rphy *rphy) transport_remove_device(dev); device_del(dev); - transport_destroy_device(dev); - - mutex_lock(&sas_host->lock); - list_del(&rphy->list); - mutex_unlock(&sas_host->lock); parent->rphy = NULL; - - put_device(dev); } -EXPORT_SYMBOL(sas_rphy_delete); +EXPORT_SYMBOL(sas_rphy_remove); /** * scsi_is_sas_rphy -- check if a struct device represents a SAS remote PHY diff --git a/include/scsi/scsi_transport_sas.h b/include/scsi/scsi_transport_sas.h index 45d58598c3ee..9aedc19820b0 100644 --- a/include/scsi/scsi_transport_sas.h +++ b/include/scsi/scsi_transport_sas.h @@ -182,6 +182,7 @@ extern struct sas_rphy *sas_end_device_alloc(struct sas_port *); extern struct sas_rphy *sas_expander_alloc(struct sas_port *, enum sas_device_type); void sas_rphy_free(struct sas_rphy *); extern int sas_rphy_add(struct sas_rphy *); +extern void sas_rphy_remove(struct sas_rphy *); extern void sas_rphy_delete(struct sas_rphy *); extern int scsi_is_sas_rphy(const struct device *); -- 2.34.1