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@@ -14,6 +14,7 @@
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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+#include <linux/smp_lock.h>
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#include <linux/kdev_t.h>
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#include <linux/cdev.h>
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#include <linux/fs.h>
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@@ -32,17 +33,20 @@ static int openCnt;
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static int gio_open(struct inode *inode, struct file *filp)
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{
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int minor;
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+ int ret = -ENOENT;
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+ lock_kernel();
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minor = MINOR(inode->i_rdev);
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if (minor < DEVCOUNT) {
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if (openCnt > 0) {
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- return -EALREADY;
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+ ret = -EALREADY;
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} else {
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openCnt++;
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- return 0;
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+ ret = 0;
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}
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}
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- return -ENOENT;
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+ unlock_kernel();
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+ return ret;
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}
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static int gio_close(struct inode *inode, struct file *filp)
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