Add a bunch of cycle_kernel_lock() calls

All of the open() functions which don't need the BKL on their face may
still depend on its acquisition to serialize opens against driver
initialization.  So make those functions acquire then release the BKL to be
on the safe side.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

4 files changed, 10 insertions, 7 deletions

diff --git a/drivers/scsi/3w-9xxx.c b/drivers/scsi/3w-9xxx.c
index 2239d16..eaa805d 100644
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -84,6 +84,7 @@
 #include <linux/pci.h>
 #include <linux/time.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 #include <asm/io.h>
 #include <asm/irq.h>
 #include <asm/uaccess.h>
@@ -862,13 +863,13 @@ out:
 } /* End twa_chrdev_ioctl() */
 
 /* This function handles open for the character device */
-/* NOTE that this function will race with remove; adding BKL
-   will not help. */
+/* NOTE that this function will race with remove. */
 static int twa_chrdev_open(struct inode *inode, struct file *file)
 {
 	unsigned int minor_number;
 	int retval = TW_IOCTL_ERROR_OS_ENODEV;
 
+	cycle_kernel_lock();
 	minor_number = iminor(inode);
 	if (minor_number >= twa_device_extension_count)
 		goto out;
diff --git a/drivers/scsi/3w-xxxx.c b/drivers/scsi/3w-xxxx.c
index bbff029..a0537f0 100644
--- a/drivers/scsi/3w-xxxx.c
+++ b/drivers/scsi/3w-xxxx.c
@@ -198,6 +198,7 @@
 
 #include <linux/module.h>
 #include <linux/reboot.h>
+#include <linux/smp_lock.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/moduleparam.h>
@@ -1027,12 +1028,12 @@ out:
 } /* End tw_chrdev_ioctl() */
 
 /* This function handles open for the character device */
-/* NOTE that this function races with remove - adding BKL
-   won't help */
+/* NOTE that this function races with remove. */
 static int tw_chrdev_open(struct inode *inode, struct file *file)
 {
 	unsigned int minor_number;
 
+	cycle_kernel_lock();
 	dprintk(KERN_WARNING "3w-xxxx: tw_ioctl_open()\n");
 
 	minor_number = iminor(inode);
diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index c9aa2c4..28c9da7 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -46,6 +46,7 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/dma-mapping.h>
+#include <linux/smp_lock.h>
 #include <scsi/scsicam.h>
 
 #include "scsi.h"
@@ -3273,12 +3274,11 @@ mega_init_scb(adapter_t *adapter)
  *
  * Routines for the character/ioctl interface to the driver. Find out if this
  * is a valid open. 
- *
- * No BKL needed here.
  */
 static int
 megadev_open (struct inode *inode, struct file *filep)
 {
+	cycle_kernel_lock();
 	/*
 	 * Only allow superuser to access private ioctl interface
 	 */
diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index 81374b7..fc7ac15 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -33,6 +33,7 @@
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
+#include <linux/smp_lock.h>
 #include <linux/uio.h>
 #include <asm/uaccess.h>
 #include <linux/fs.h>
@@ -2860,10 +2861,10 @@ static void megasas_shutdown(struct pci_dev *pdev)
 
 /**
  * megasas_mgmt_open -	char node "open" entry point
- * No BKL is needed here.
  */
 static int megasas_mgmt_open(struct inode *inode, struct file *filep)
 {
+	cycle_kernel_lock();
 	/*
 	 * Allow only those users with admin rights
 	 */