X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fchar_dev.c;h=a173551e19d79da5ae6132be9eaa24522abd4580;hb=4722607db6a78bd7748c51fa4c8d7371da797254;hp=164a45cdaf5f96cd8e6ac92b617c0525f0aaf8ff;hpb=2363cc0264c42636e9e7622f78dde5c2f66beb8e;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/char_dev.c b/fs/char_dev.c
index 164a45c..a173551 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -13,7 +13,6 @@
 #include <linux/major.h>
 #include <linux/errno.h>
 #include <linux/module.h>
-#include <linux/smp_lock.h>
 #include <linux/seq_file.h>
 
 #include <linux/kobject.h>
@@ -22,9 +21,6 @@
 #include <linux/mutex.h>
 #include <linux/backing-dev.h>
 
-#ifdef CONFIG_KMOD
-#include <linux/kmod.h>
-#endif
 #include "internal.h"
 
 /*
@@ -55,7 +51,6 @@ static struct char_device_struct {
 	unsigned int baseminor;
 	int minorct;
 	char name[64];
-	struct file_operations *fops;
 	struct cdev *cdev;		/* will die */
 } *chrdevs[CHRDEV_MAJOR_HASH_SIZE];
 
@@ -124,7 +119,7 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor,
 	cd->major = major;
 	cd->baseminor = baseminor;
 	cd->minorct = minorct;
-	strncpy(cd->name,name, 64);
+	strlcpy(cd->name, name, sizeof(cd->name));
 
 	i = major_to_index(major);
 
@@ -321,14 +316,13 @@ void unregister_chrdev_region(dev_t from, unsigned count)
 	}
 }
 
-int unregister_chrdev(unsigned int major, const char *name)
+void unregister_chrdev(unsigned int major, const char *name)
 {
 	struct char_device_struct *cd;
 	cd = __unregister_chrdev_region(major, 0, 256);
 	if (cd && cd->cdev)
 		cdev_del(cd->cdev);
 	kfree(cd);
-	return 0;
 }
 
 static DEFINE_SPINLOCK(cdev_lock);
@@ -358,7 +352,7 @@ void cdev_put(struct cdev *p)
 /*
  * Called every time a character special file is opened
  */
-int chrdev_open(struct inode * inode, struct file * filp)
+static int chrdev_open(struct inode *inode, struct file *filp)
 {
 	struct cdev *p;
 	struct cdev *new = NULL;
@@ -375,10 +369,11 @@ int chrdev_open(struct inode * inode, struct file * filp)
 			return -ENXIO;
 		new = container_of(kobj, struct cdev, kobj);
 		spin_lock(&cdev_lock);
+		/* Check i_cdev again in case somebody beat us to it while
+		   we dropped the lock. */
 		p = inode->i_cdev;
 		if (!p) {
 			inode->i_cdev = p = new;
-			inode->i_cindex = idx;
 			list_add(&inode->i_devices, &p->list);
 			new = NULL;
 		} else if (!cdev_get(p))
@@ -389,21 +384,37 @@ int chrdev_open(struct inode * inode, struct file * filp)
 	cdev_put(new);
 	if (ret)
 		return ret;
+
+	ret = -ENXIO;
 	filp->f_op = fops_get(p->ops);
-	if (!filp->f_op) {
-		cdev_put(p);
-		return -ENXIO;
-	}
+	if (!filp->f_op)
+		goto out_cdev_put;
+
 	if (filp->f_op->open) {
-		lock_kernel();
 		ret = filp->f_op->open(inode,filp);
-		unlock_kernel();
+		if (ret)
+			goto out_cdev_put;
 	}
-	if (ret)
-		cdev_put(p);
+
+	return 0;
+
+ out_cdev_put:
+	cdev_put(p);
 	return ret;
 }
 
+int cdev_index(struct inode *inode)
+{
+	int idx;
+	struct kobject *kobj;
+
+	kobj = kobj_lookup(cdev_map, inode->i_rdev, &idx);
+	if (!kobj)
+		return -1;
+	kobject_put(kobj);
+	return idx;
+}
+
 void cd_forget(struct inode *inode)
 {
 	spin_lock(&cdev_lock);
@@ -511,9 +522,8 @@ struct cdev *cdev_alloc(void)
 {
 	struct cdev *p = kzalloc(sizeof(struct cdev), GFP_KERNEL);
 	if (p) {
-		p->kobj.ktype = &ktype_cdev_dynamic;
 		INIT_LIST_HEAD(&p->list);
-		kobject_init(&p->kobj);
+		kobject_init(&p->kobj, &ktype_cdev_dynamic);
 	}
 	return p;
 }
@@ -530,8 +540,7 @@ void cdev_init(struct cdev *cdev, const struct file_operations *fops)
 {
 	memset(cdev, 0, sizeof *cdev);
 	INIT_LIST_HEAD(&cdev->list);
-	cdev->kobj.ktype = &ktype_cdev_default;
-	kobject_init(&cdev->kobj);
+	kobject_init(&cdev->kobj, &ktype_cdev_default);
 	cdev->ops = fops;
 }
 
@@ -546,6 +555,7 @@ static struct kobject *base_probe(dev_t dev, int *part, void *data)
 void __init chrdev_init(void)
 {
 	cdev_map = kobj_map_init(base_probe, &chrdevs_lock);
+	bdi_init(&directly_mappable_cdev_bdi);
 }
 
 
@@ -557,6 +567,7 @@ EXPORT_SYMBOL(cdev_init);
 EXPORT_SYMBOL(cdev_alloc);
 EXPORT_SYMBOL(cdev_del);
 EXPORT_SYMBOL(cdev_add);
+EXPORT_SYMBOL(cdev_index);
 EXPORT_SYMBOL(register_chrdev);
 EXPORT_SYMBOL(unregister_chrdev);
 EXPORT_SYMBOL(directly_mappable_cdev_bdi);