memstick: use fully asynchronous request processing

Instead of using a separate thread to pump requests from block layer queue
to memstick, do so inline, utilizing the callback design of the memstick.

[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 54 insertions, 30 deletions

diff --git a/drivers/memstick/host/jmb38x_ms.c b/drivers/memstick/host/jmb38x_ms.c
index 9d82e67737db..3485c63d20b0 100644
--- a/drivers/memstick/host/jmb38x_ms.c
+++ b/drivers/memstick/host/jmb38x_ms.c
@@ -50,6 +50,7 @@ struct jmb38x_ms_host {
         struct jmb38x_ms        *chip;
         void __iomem            *addr;
         spinlock_t              lock;
+        struct tasklet_struct   notify;
         int                     id;
         char                    host_id[32];
         int                     irq;
@@ -590,25 +591,35 @@ static void jmb38x_ms_abort(unsigned long data)
         spin_unlock_irqrestore(&host->lock, flags);
 }
 
-static void jmb38x_ms_request(struct memstick_host *msh)
+static void jmb38x_ms_req_tasklet(unsigned long data)
 {
+        struct memstick_host *msh = (struct memstick_host *)data;
         struct jmb38x_ms_host *host = memstick_priv(msh);
         unsigned long flags;
         int rc;
 
         spin_lock_irqsave(&host->lock, flags);
-        if (host->req) {
-                spin_unlock_irqrestore(&host->lock, flags);
-                BUG();
-                return;
+        if (!host->req) {
+                do {
+                        rc = memstick_next_req(msh, &host->req);
+                        dev_dbg(&host->chip->pdev->dev, "tasklet req %d\n", rc);
+                } while (!rc && jmb38x_ms_issue_cmd(msh));
         }
-
-        do {
-                rc = memstick_next_req(msh, &host->req);
-        } while (!rc && jmb38x_ms_issue_cmd(msh));
         spin_unlock_irqrestore(&host->lock, flags);
 }
 
+static void jmb38x_ms_dummy_submit(struct memstick_host *msh)
+{
+        return;
+}
+
+static void jmb38x_ms_submit_req(struct memstick_host *msh)
+{
+        struct jmb38x_ms_host *host = memstick_priv(msh);
+
+        tasklet_schedule(&host->notify);
+}
+
 static int jmb38x_ms_reset(struct jmb38x_ms_host *host)
 {
         int cnt;
@@ -816,7 +827,9 @@ static struct memstick_host *jmb38x_ms_alloc_host(struct jmb38x_ms *jm, int cnt)
                  host->id);
         host->irq = jm->pdev->irq;
         host->timeout_jiffies = msecs_to_jiffies(1000);
-        msh->request = jmb38x_ms_request;
+
+        tasklet_init(&host->notify, jmb38x_ms_req_tasklet, (unsigned long)msh);
+        msh->request = jmb38x_ms_submit_req;
         msh->set_param = jmb38x_ms_set_param;
 
         msh->caps = MEMSTICK_CAP_PAR4 | MEMSTICK_CAP_PAR8;
@@ -928,6 +941,8 @@ static void jmb38x_ms_remove(struct pci_dev *dev)
 
                 host = memstick_priv(jm->hosts[cnt]);
 
+                jm->hosts[cnt]->request = jmb38x_ms_dummy_submit;
+                tasklet_kill(&host->notify);
                 writel(0, host->addr + INT_SIGNAL_ENABLE);
                 writel(0, host->addr + INT_STATUS_ENABLE);
                 mmiowb();
diff --git a/drivers/memstick/host/tifm_ms.c b/drivers/memstick/host/tifm_ms.c
index 14458764588c..d32d6ad8f3fc 100644
--- a/drivers/memstick/host/tifm_ms.c
+++ b/drivers/memstick/host/tifm_ms.c
@@ -71,6 +71,7 @@ struct tifm_ms {
         struct tifm_dev         *dev;
         struct timer_list       timer;
         struct memstick_request *req;
+        struct tasklet_struct   notify;
         unsigned int            mode_mask;
         unsigned int            block_pos;
         unsigned long           timeout_jiffies;
@@ -455,40 +456,45 @@ static void tifm_ms_card_event(struct tifm_dev *sock)
         return;
 }
 
-static void tifm_ms_request(struct memstick_host *msh)
+static void tifm_ms_req_tasklet(unsigned long data)
 {
+        struct memstick_host *msh = (struct memstick_host *)data;
         struct tifm_ms *host = memstick_priv(msh);
         struct tifm_dev *sock = host->dev;
         unsigned long flags;
         int rc;
 
         spin_lock_irqsave(&sock->lock, flags);
-        if (host->req) {
-                printk(KERN_ERR "%s : unfinished request detected\n",
-                       sock->dev.bus_id);
-                spin_unlock_irqrestore(&sock->lock, flags);
-                tifm_eject(host->dev);
-                return;
-        }
+        if (!host->req) {
+                if (host->eject) {
+                        do {
+                                rc = memstick_next_req(msh, &host->req);
+                                if (!rc)
+                                        host->req->error = -ETIME;
+                        } while (!rc);
+                        spin_unlock_irqrestore(&sock->lock, flags);
+                        return;
+                }
 
-        if (host->eject) {
                 do {
                         rc = memstick_next_req(msh, &host->req);
-                        if (!rc)
-                                host->req->error = -ETIME;
-                } while (!rc);
-                spin_unlock_irqrestore(&sock->lock, flags);
-                return;
+                } while (!rc && tifm_ms_issue_cmd(host));
         }
-
-        do {
-                rc = memstick_next_req(msh, &host->req);
-        } while (!rc && tifm_ms_issue_cmd(host));
-
         spin_unlock_irqrestore(&sock->lock, flags);
+}
+
+static void tifm_ms_dummy_submit(struct memstick_host *msh)
+{
         return;
 }
 
+static void tifm_ms_submit_req(struct memstick_host *msh)
+{
+        struct tifm_ms *host = memstick_priv(msh);
+
+        tasklet_schedule(&host->notify);
+}
+
 static int tifm_ms_set_param(struct memstick_host *msh,
                              enum memstick_param param,
                              int value)
@@ -569,8 +575,9 @@ static int tifm_ms_probe(struct tifm_dev *sock)
         host->timeout_jiffies = msecs_to_jiffies(1000);
 
         setup_timer(&host->timer, tifm_ms_abort, (unsigned long)host);
+        tasklet_init(&host->notify, tifm_ms_req_tasklet, (unsigned long)msh);
 
-        msh->request = tifm_ms_request;
+        msh->request = tifm_ms_submit_req;
         msh->set_param = tifm_ms_set_param;
         sock->card_event = tifm_ms_card_event;
         sock->data_event = tifm_ms_data_event;
@@ -592,6 +599,8 @@ static void tifm_ms_remove(struct tifm_dev *sock)
         int rc = 0;
         unsigned long flags;
 
+        msh->request = tifm_ms_dummy_submit;
+        tasklet_kill(&host->notify);
         spin_lock_irqsave(&sock->lock, flags);
         host->eject = 1;
         if (host->req) {