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>

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 4a1b9e7464a..05d5ef172ca 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -9,7 +9,7 @@
 #include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
 #include <linux/skbuff.h>
 #include "aoe.h"
 
@@ -37,6 +37,7 @@ struct ErrMsg {
 	char *msg;
 };
 
+static DEFINE_MUTEX(aoechr_mutex);
 static struct ErrMsg emsgs[NMSG];
 static int emsgs_head_idx, emsgs_tail_idx;
 static struct completion emsgs_comp;
@@ -183,16 +184,16 @@ aoechr_open(struct inode *inode, struct file *filp)
 {
 	int n, i;
 
-	lock_kernel();
+	mutex_lock(&aoechr_mutex);
 	n = iminor(inode);
 	filp->private_data = (void *) (unsigned long) n;
 
 	for (i = 0; i < ARRAY_SIZE(chardevs); ++i)
 		if (chardevs[i].minor == n) {
-			unlock_kernel();
+			mutex_unlock(&aoechr_mutex);
 			return 0;
 		}
-	unlock_kernel();
+	mutex_unlock(&aoechr_mutex);
 	return -EINVAL;
 }