block: autoconvert trivial BKL users to private mutex

The block device drivers have all gained new lock_kernel
calls from a recent pushdown, and some of the drivers
were already using the BKL before.

This turns the BKL into a set of per-driver mutexes.
Still need to check whether this is safe to do.

file=$1
name=$2
if grep -q lock_kernel ${file} ; then
    if grep -q 'include.*linux.mutex.h' ${file} ; then
            sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
    else
            sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
    fi
    sed -i ${file} \
        -e "/^#include.*linux.mutex.h/,$ {
                1,/^\(static\|int\|long\)/ {
                     /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);

} }"  \
    -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
    -e '/[      ]*cycle_kernel_lock();/d'
else
    sed -i -e '/include.*\<smp_lock.h\>/d' ${file}  \
                -e '/cycle_kernel_lock()/d'
fi

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index b1cbeb5..1e85678 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -57,7 +57,6 @@
 #include <linux/seq_file.h>
 #include <linux/miscdevice.h>
 #include <linux/freezer.h>
-#include <linux/smp_lock.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <scsi/scsi_cmnd.h>
@@ -86,6 +85,7 @@
 
 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
 
+static DEFINE_MUTEX(pktcdvd_mutex);
 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
 static struct proc_dir_entry *pkt_proc;
 static int pktdev_major;
@@ -2383,7 +2383,7 @@
 
 	VPRINTK(DRIVER_NAME": entering open\n");
 
-	lock_kernel();
+	mutex_lock(&pktcdvd_mutex);
 	mutex_lock(&ctl_mutex);
 	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
 	if (!pd) {
@@ -2411,7 +2411,7 @@
 	}
 
 	mutex_unlock(&ctl_mutex);
-	unlock_kernel();
+	mutex_unlock(&pktcdvd_mutex);
 	return 0;
 
 out_dec:
@@ -2419,7 +2419,7 @@
 out:
 	VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
 	mutex_unlock(&ctl_mutex);
-	unlock_kernel();
+	mutex_unlock(&pktcdvd_mutex);
 	return ret;
 }
 
@@ -2428,7 +2428,7 @@
 	struct pktcdvd_device *pd = disk->private_data;
 	int ret = 0;
 
-	lock_kernel();
+	mutex_lock(&pktcdvd_mutex);
 	mutex_lock(&ctl_mutex);
 	pd->refcnt--;
 	BUG_ON(pd->refcnt < 0);
@@ -2437,7 +2437,7 @@
 		pkt_release_dev(pd, flush);
 	}
 	mutex_unlock(&ctl_mutex);
-	unlock_kernel();
+	mutex_unlock(&pktcdvd_mutex);
 	return ret;
 }
 
@@ -2773,7 +2773,7 @@
 	VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
 		MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
 
-	lock_kernel();
+	mutex_lock(&pktcdvd_mutex);
 	switch (cmd) {
 	case CDROMEJECT:
 		/*
@@ -2798,7 +2798,7 @@
 		VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
 		ret = -ENOTTY;
 	}
-	unlock_kernel();
+	mutex_unlock(&pktcdvd_mutex);
 
 	return ret;
 }