kfifo: fix warn_unused_result

Fix the "ignoring return value of '...', declared with attribute
warn_unused_result" compiler warning in several users of the new kfifo
API.

It removes the __must_check attribute from kfifo_in() and
kfifo_in_locked() which must not necessary performed.

Fix the allocation bug in the nozomi driver file, by moving out the
kfifo_alloc from the interrupt handler into the probe function.

Fix the kfifo_out() and kfifo_out_locked() users to handle a unexpected
end of fifo.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 27 insertions, 4 deletions

diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c
index 9ef243429014..7d73cd430340 100644
--- a/drivers/char/nozomi.c
+++ b/drivers/char/nozomi.c
@@ -685,8 +685,6 @@ static int nozomi_read_config_table(struct nozomi *dc)
                 dump_table(dc);
 
                 for (i = PORT_MDM; i < MAX_PORT; i++) {
-                        kfifo_alloc(&dc->port[i].fifo_ul,
-                                FIFO_BUFFER_SIZE_UL, GFP_ATOMIC);
                         memset(&dc->port[i].ctrl_dl, 0, sizeof(struct ctrl_dl));
                         memset(&dc->port[i].ctrl_ul, 0, sizeof(struct ctrl_ul));
                 }
@@ -1433,6 +1431,16 @@ static int __devinit nozomi_card_init(struct pci_dev *pdev,
                 goto err_free_sbuf;
         }
 
+        for (i = PORT_MDM; i < MAX_PORT; i++) {
+                if (kfifo_alloc(&dc->port[i].fifo_ul,
+                      FIFO_BUFFER_SIZE_UL, GFP_ATOMIC)) {
+                        dev_err(&pdev->dev,
+                                        "Could not allocate kfifo buffer\n");
+                        ret = -ENOMEM;
+                        goto err_free_kfifo;
+                }
+        }
+
         spin_lock_init(&dc->spin_mutex);
 
         nozomi_setup_private_data(dc);
@@ -1445,7 +1453,7 @@ static int __devinit nozomi_card_init(struct pci_dev *pdev,
                         NOZOMI_NAME, dc);
         if (unlikely(ret)) {
                 dev_err(&pdev->dev, "can't request irq %d\n", pdev->irq);
-                goto err_free_sbuf;
+                goto err_free_kfifo;
         }
 
         DBG1("base_addr: %p", dc->base_addr);
@@ -1464,13 +1472,28 @@ static int __devinit nozomi_card_init(struct pci_dev *pdev,
         dc->state = NOZOMI_STATE_ENABLED;
 
         for (i = 0; i < MAX_PORT; i++) {
+                struct device *tty_dev;
+
                 mutex_init(&dc->port[i].tty_sem);
                 tty_port_init(&dc->port[i].port);
-                tty_register_device(ntty_driver, dc->index_start + i,
+                tty_dev = tty_register_device(ntty_driver, dc->index_start + i,
                                                         &pdev->dev);
+
+                if (IS_ERR(tty_dev)) {
+                        ret = PTR_ERR(tty_dev);
+                        dev_err(&pdev->dev, "Could not allocate tty?\n");
+                        goto err_free_tty;
+                }
         }
+
         return 0;
 
+err_free_tty:
+        for (i = dc->index_start; i < dc->index_start + MAX_PORT; ++i)
+                tty_unregister_device(ntty_driver, i);
+err_free_kfifo:
+        for (i = 0; i < MAX_PORT; i++)
+                kfifo_free(&dc->port[i].fifo_ul);
 err_free_sbuf:
         kfree(dc->send_buf);
         iounmap(dc->base_addr);