[SCSI] qla2xxx: use kthread_ API

Use the kthread_ API instead of opencoding lots of hairy code for kernel
thread creation and teardown.

Also switch from semaphore-based thread wakeup to wake_up_process.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-By: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

6 files changed, 38 insertions, 74 deletions

diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index b31a03bbd14f..2e16f3285d5f 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -2414,11 +2414,7 @@ typedef struct scsi_qla_host {
         struct sns_cmd_pkt      *sns_cmd;
         dma_addr_t              sns_cmd_dma;
 
-        pid_t                   dpc_pid;
-        int                     dpc_should_die;
-        struct completion       dpc_inited;
-        struct completion       dpc_exited;
-        struct semaphore        *dpc_wait;
+        struct task_struct      *dpc_thread;
         uint8_t dpc_active;                  /* DPC routine is active */
 
         /* Timeout timers. */
diff --git a/drivers/scsi/qla2xxx/qla_gbl.h b/drivers/scsi/qla2xxx/qla_gbl.h
index ffdc2680f049..e897eadf0362 100644
--- a/drivers/scsi/qla2xxx/qla_gbl.h
+++ b/drivers/scsi/qla2xxx/qla_gbl.h
@@ -81,6 +81,8 @@ extern struct fw_blob *qla2x00_request_firmware(scsi_qla_host_t *);
 
 extern int qla2x00_wait_for_hba_online(scsi_qla_host_t *);
 
+extern void qla2xxx_wake_dpc(scsi_qla_host_t *);
+
 /*
  * Global Function Prototypes in qla_iocb.c source file.
  */
diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index 42aa7a7c1a73..c15458c2bf32 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -838,9 +838,7 @@ qla2x00_status_entry(scsi_qla_host_t *ha, void *pkt)
                 qla_printk(KERN_WARNING, ha, "Status Entry invalid handle.\n");
 
                 set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
-                if (ha->dpc_wait && !ha->dpc_active)
-                        up(ha->dpc_wait);
-
+                qla2xxx_wake_dpc(ha);
                 return;
         }
         cp = sp->cmd;
@@ -1271,8 +1269,7 @@ qla2x00_error_entry(scsi_qla_host_t *ha, sts_entry_t *pkt)
                     "Error entry - invalid handle\n");
 
                 set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
-                if (ha->dpc_wait && !ha->dpc_active)
-                        up(ha->dpc_wait);
+                qla2xxx_wake_dpc(ha);
         }
 }
 
diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index 363dfdd042b0..584cc2f6dd35 100644
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/qla_mbx.c
@@ -284,9 +284,7 @@ qla2x00_mailbox_command(scsi_qla_host_t *ha, mbx_cmd_t *mcp)
                             "Mailbox command timeout occured. Scheduling ISP "
                             "abort.\n");
                         set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
-                        if (ha->dpc_wait && !ha->dpc_active)
-                                up(ha->dpc_wait);
-
+                        qla2xxx_wake_dpc(ha);
                 } else if (!abort_active) {
                         /* call abort directly since we are in the DPC thread */
                         DEBUG(printk("%s(%ld): timeout calling abort_isp\n",
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 9f91f1a20542..43ca0d8ca384 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -8,8 +8,8 @@
 
 #include <linux/moduleparam.h>
 #include <linux/vmalloc.h>
-#include <linux/smp_lock.h>
 #include <linux/delay.h>
+#include <linux/kthread.h>
 
 #include <scsi/scsi_tcq.h>
 #include <scsi/scsicam.h>
@@ -1307,8 +1307,6 @@ int qla2x00_probe_one(struct pci_dev *pdev, struct qla_board_info *brd_info)
         ha->brd_info = brd_info;
         sprintf(ha->host_str, "%s_%ld", ha->brd_info->drv_name, ha->host_no);
 
-        ha->dpc_pid = -1;
-
         /* Configure PCI I/O space */
         ret = qla2x00_iospace_config(ha);
         if (ret)
@@ -1449,9 +1447,6 @@ int qla2x00_probe_one(struct pci_dev *pdev, struct qla_board_info *brd_info)
          */
         spin_lock_init(&ha->mbx_reg_lock);
 
-        init_completion(&ha->dpc_inited);
-        init_completion(&ha->dpc_exited);
-
         qla2x00_config_dma_addressing(ha);
         if (qla2x00_mem_alloc(ha)) {
                 qla_printk(KERN_WARNING, ha,
@@ -1478,16 +1473,14 @@ int qla2x00_probe_one(struct pci_dev *pdev, struct qla_board_info *brd_info)
         /*
          * Startup the kernel thread for this host adapter
          */
-        ha->dpc_should_die = 0;
-        ha->dpc_pid = kernel_thread(qla2x00_do_dpc, ha, 0);
-        if (ha->dpc_pid < 0) {
+        ha->dpc_thread = kthread_create(qla2x00_do_dpc, ha,
+                        "%s_dpc", ha->host_str);
+        if (IS_ERR(ha->dpc_thread)) {
                 qla_printk(KERN_WARNING, ha,
                     "Unable to start DPC thread!\n");
-
-                ret = -ENODEV;
+                ret = PTR_ERR(ha->dpc_thread);
                 goto probe_failed;
         }
-        wait_for_completion(&ha->dpc_inited);
 
         host->this_id = 255;
         host->cmd_per_lun = 3;
@@ -1621,8 +1614,6 @@ EXPORT_SYMBOL_GPL(qla2x00_remove_one);
 static void
 qla2x00_free_device(scsi_qla_host_t *ha)
 {
-        int ret;
-
         /* Abort any outstanding IO descriptors. */
         if (!IS_QLA2100(ha) && !IS_QLA2200(ha))
                 qla2x00_cancel_io_descriptors(ha);
@@ -1632,18 +1623,15 @@ qla2x00_free_device(scsi_qla_host_t *ha)
                 qla2x00_stop_timer(ha);
 
         /* Kill the kernel thread for this host */
-        if (ha->dpc_pid >= 0) {
-                ha->dpc_should_die = 1;
-                wmb();
-                ret = kill_proc(ha->dpc_pid, SIGHUP, 1);
-                if (ret) {
-                        qla_printk(KERN_ERR, ha,
-                            "Unable to signal DPC thread -- (%d)\n", ret);
+        if (ha->dpc_thread) {
+                struct task_struct *t = ha->dpc_thread;
 
-                        /* TODO: SOMETHING MORE??? */
-                } else {
-                        wait_for_completion(&ha->dpc_exited);
-                }
+                /*
+                 * qla2xxx_wake_dpc checks for ->dpc_thread
+                 * so we need to zero it out.
+                 */
+                ha->dpc_thread = NULL;
+                kthread_stop(t);
         }
 
         /* Stop currently executing firmware. */
@@ -1775,8 +1763,8 @@ qla2x00_mark_all_devices_lost(scsi_qla_host_t *ha, int defer)
                 atomic_set(&fcport->state, FCS_DEVICE_LOST);
         }
 
-        if (defer && ha->dpc_wait && !ha->dpc_active)
-                up(ha->dpc_wait);
+        if (defer)
+                qla2xxx_wake_dpc(ha);
 }
 
 /*
@@ -1993,7 +1981,6 @@ qla2x00_mem_free(scsi_qla_host_t *ha)
 {
         struct list_head        *fcpl, *fcptemp;
         fc_port_t       *fcport;
-        unsigned int    wtime;/* max wait time if mbx cmd is busy. */
 
         if (ha == NULL) {
                 /* error */
@@ -2001,11 +1988,6 @@ qla2x00_mem_free(scsi_qla_host_t *ha)
                 return;
         }
 
-        /* Make sure all other threads are stopped. */
-        wtime = 60 * 1000;
-        while (ha->dpc_wait && wtime)
-                wtime = msleep_interruptible(wtime);
-
         /* free ioctl memory */
         qla2x00_free_ioctl_mem(ha);
 
@@ -2156,7 +2138,6 @@ qla2x00_free_sp_pool( scsi_qla_host_t *ha)
 static int
 qla2x00_do_dpc(void *data)
 {
-        DECLARE_MUTEX_LOCKED(sem);
         scsi_qla_host_t *ha;
         fc_port_t       *fcport;
         uint8_t         status;
@@ -2164,32 +2145,19 @@ qla2x00_do_dpc(void *data)
 
         ha = (scsi_qla_host_t *)data;
 
-        lock_kernel();
-
-        daemonize("%s_dpc", ha->host_str);
-        allow_signal(SIGHUP);
-
-        ha->dpc_wait = &sem;
-
         set_user_nice(current, -20);
 
-        unlock_kernel();
-
-        complete(&ha->dpc_inited);
-
-        while (1) {
+        while (!kthread_should_stop()) {
                 DEBUG3(printk("qla2x00: DPC handler sleeping\n"));
 
-                if (down_interruptible(&sem))
-                        break;
-
-                if (ha->dpc_should_die)
-                        break;
+                set_current_state(TASK_INTERRUPTIBLE);
+                schedule();
+                __set_current_state(TASK_RUNNING);
 
                 DEBUG3(printk("qla2x00: DPC handler waking up\n"));
 
                 /* Initialization not yet finished. Don't do anything yet. */
-                if (!ha->flags.init_done || ha->dpc_active)
+                if (!ha->flags.init_done)
                         continue;
 
                 DEBUG3(printk("scsi(%ld): DPC handler\n", ha->host_no));
@@ -2356,10 +2324,16 @@ qla2x00_do_dpc(void *data)
         /*
          * Make sure that nobody tries to wake us up again.
          */
-        ha->dpc_wait = NULL;
         ha->dpc_active = 0;
 
-        complete_and_exit(&ha->dpc_exited, 0);
+        return 0;
+}
+
+void
+qla2xxx_wake_dpc(scsi_qla_host_t *ha)
+{
+        if (ha->dpc_thread)
+                wake_up_process(ha->dpc_thread);
 }
 
 /*
@@ -2540,11 +2514,8 @@ qla2x00_timer(scsi_qla_host_t *ha)
             test_bit(LOGIN_RETRY_NEEDED, &ha->dpc_flags) ||
             test_bit(RESET_MARKER_NEEDED, &ha->dpc_flags) ||
             test_bit(BEACON_BLINK_NEEDED, &ha->dpc_flags) ||
-            test_bit(RELOGIN_NEEDED, &ha->dpc_flags)) &&
-            ha->dpc_wait && !ha->dpc_active) {
-
-                up(ha->dpc_wait);
-        }
+            test_bit(RELOGIN_NEEDED, &ha->dpc_flags)))
+                qla2xxx_wake_dpc(ha);
 
         qla2x00_restart_timer(ha, WATCH_INTERVAL);
 }
diff --git a/drivers/scsi/qla2xxx/qla_sup.c b/drivers/scsi/qla2xxx/qla_sup.c
index 3866a5760f15..8d68c463cd5b 100644
--- a/drivers/scsi/qla2xxx/qla_sup.c
+++ b/drivers/scsi/qla2xxx/qla_sup.c
@@ -1354,7 +1354,7 @@ qla2x00_resume_hba(struct scsi_qla_host *ha)
         /* Resume HBA. */
         clear_bit(MBX_UPDATE_FLASH_ACTIVE, &ha->mbx_cmd_flags);
         set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
-        up(ha->dpc_wait);
+        qla2xxx_wake_dpc(ha);
         qla2x00_wait_for_hba_online(ha);
         scsi_unblock_requests(ha->host);
 }
@@ -1652,7 +1652,7 @@ qla24xx_write_optrom_data(struct scsi_qla_host *ha, uint8_t *buf,
         /* Resume HBA -- RISC reset needed. */
         clear_bit(MBX_UPDATE_FLASH_ACTIVE, &ha->mbx_cmd_flags);
         set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
-        up(ha->dpc_wait);
+        qla2xxx_wake_dpc(ha);
         qla2x00_wait_for_hba_online(ha);
         scsi_unblock_requests(ha->host);