1 files changed, 23 insertions, 90 deletions

diff --git a/fs/char_dev.c b/fs/char_dev.c
index 21195c48163..f3418f7a6e9 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -15,10 +15,12 @@
 #include <linux/module.h>
 #include <linux/smp_lock.h>
 #include <linux/devfs_fs_kernel.h>
+#include <linux/seq_file.h>
 
 #include <linux/kobject.h>
 #include <linux/kobj_map.h>
 #include <linux/cdev.h>
+#include <linux/mutex.h>
 
 #ifdef CONFIG_KMOD
 #include <linux/kmod.h>
@@ -26,9 +28,7 @@
 
 static struct kobj_map *cdev_map;
 
-#define MAX_PROBE_HASH 255	/* random */
-
-static DECLARE_MUTEX(chrdevs_lock);
+static DEFINE_MUTEX(chrdevs_lock);
 
 static struct char_device_struct {
 	struct char_device_struct *next;
@@ -38,93 +38,29 @@ static struct char_device_struct {
 	char name[64];
 	struct file_operations *fops;
 	struct cdev *cdev;		/* will die */
-} *chrdevs[MAX_PROBE_HASH];
+} *chrdevs[CHRDEV_MAJOR_HASH_SIZE];
 
 /* index in the above */
 static inline int major_to_index(int major)
 {
-	return major % MAX_PROBE_HASH;
+	return major % CHRDEV_MAJOR_HASH_SIZE;
 }
 
-struct chrdev_info {
-	int index;
-	struct char_device_struct *cd;
-};
-
-void *get_next_chrdev(void *dev)
-{
-	struct chrdev_info *info;
-
-	if (dev == NULL) {
-		info = kmalloc(sizeof(*info), GFP_KERNEL);
-		if (!info)
-			goto out;
-		info->index=0;
-		info->cd = chrdevs[info->index];
-		if (info->cd)
-			goto out;
-	} else {
-		info = dev;
-	}
-
-	while (info->index < ARRAY_SIZE(chrdevs)) {
-		if (info->cd)
-			info->cd = info->cd->next;
-		if (info->cd)
-			goto out;
-		/*
-		 * No devices on this chain, move to the next
-		 */
-		info->index++;
-		info->cd = (info->index < ARRAY_SIZE(chrdevs)) ?
-			chrdevs[info->index] : NULL;
-		if (info->cd)
-			goto out;
-	}
-
-out:
-	return info;
-}
+#ifdef CONFIG_PROC_FS
 
-void *acquire_chrdev_list(void)
-{
-	down(&chrdevs_lock);
-	return get_next_chrdev(NULL);
-}
-
-void release_chrdev_list(void *dev)
-{
-	up(&chrdevs_lock);
-	kfree(dev);
-}
-
-
-int count_chrdev_list(void)
+void chrdev_show(struct seq_file *f, off_t offset)
 {
 	struct char_device_struct *cd;
-	int i, count;
-
-	count = 0;
 
-	for (i = 0; i < ARRAY_SIZE(chrdevs) ; i++) {
-		for (cd = chrdevs[i]; cd; cd = cd->next)
-			count++;
+	if (offset < CHRDEV_MAJOR_HASH_SIZE) {
+		mutex_lock(&chrdevs_lock);
+		for (cd = chrdevs[offset]; cd; cd = cd->next)
+			seq_printf(f, "%3d %s\n", cd->major, cd->name);
+		mutex_unlock(&chrdevs_lock);
 	}
-
-	return count;
 }
 
-int get_chrdev_info(void *dev, int *major, char **name)
-{
-	struct chrdev_info *info = dev;
-
-	if (info->cd == NULL)
-		return 1;
-
-	*major = info->cd->major;
-	*name = info->cd->name;
-	return 0;
-}
+#endif /* CONFIG_PROC_FS */
 
 /*
  * Register a single major with a specified minor range.
@@ -145,13 +81,11 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor,
 	int ret = 0;
 	int i;
 
-	cd = kmalloc(sizeof(struct char_device_struct), GFP_KERNEL);
+	cd = kzalloc(sizeof(struct char_device_struct), GFP_KERNEL);
 	if (cd == NULL)
 		return ERR_PTR(-ENOMEM);
 
-	memset(cd, 0, sizeof(struct char_device_struct));
-
-	down(&chrdevs_lock);
+	mutex_lock(&chrdevs_lock);
 
 	/* temporary */
 	if (major == 0) {
@@ -186,10 +120,10 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor,
 	}
 	cd->next = *cp;
 	*cp = cd;
-	up(&chrdevs_lock);
+	mutex_unlock(&chrdevs_lock);
 	return cd;
 out:
-	up(&chrdevs_lock);
+	mutex_unlock(&chrdevs_lock);
 	kfree(cd);
 	return ERR_PTR(ret);
 }
@@ -200,7 +134,7 @@ __unregister_chrdev_region(unsigned major, unsigned baseminor, int minorct)
 	struct char_device_struct *cd = NULL, **cp;
 	int i = major_to_index(major);
 
-	down(&chrdevs_lock);
+	mutex_lock(&chrdevs_lock);
 	for (cp = &chrdevs[i]; *cp; cp = &(*cp)->next)
 		if ((*cp)->major == major &&
 		    (*cp)->baseminor == baseminor &&
@@ -210,7 +144,7 @@ __unregister_chrdev_region(unsigned major, unsigned baseminor, int minorct)
 		cd = *cp;
 		*cp = cd->next;
 	}
-	up(&chrdevs_lock);
+	mutex_unlock(&chrdevs_lock);
 	return cd;
 }
 
@@ -251,7 +185,7 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
 }
 
 int register_chrdev(unsigned int major, const char *name,
-		    struct file_operations *fops)
+		    const struct file_operations *fops)
 {
 	struct char_device_struct *cd;
 	struct cdev *cdev;
@@ -407,7 +341,7 @@ static void cdev_purge(struct cdev *cdev)
  * is contain the open that then fills in the correct operations
  * depending on the special file...
  */
-struct file_operations def_chr_fops = {
+const struct file_operations def_chr_fops = {
 	.open = chrdev_open,
 };
 
@@ -465,9 +399,8 @@ static struct kobj_type ktype_cdev_dynamic = {
 
 struct cdev *cdev_alloc(void)
 {
-	struct cdev *p = kmalloc(sizeof(struct cdev), GFP_KERNEL);
+	struct cdev *p = kzalloc(sizeof(struct cdev), GFP_KERNEL);
 	if (p) {
-		memset(p, 0, sizeof(struct cdev));
 		p->kobj.ktype = &ktype_cdev_dynamic;
 		INIT_LIST_HEAD(&p->list);
 		kobject_init(&p->kobj);
@@ -475,7 +408,7 @@ struct cdev *cdev_alloc(void)
 	return p;
 }
 
-void cdev_init(struct cdev *cdev, struct file_operations *fops)
+void cdev_init(struct cdev *cdev, const struct file_operations *fops)
 {
 	memset(cdev, 0, sizeof *cdev);
 	INIT_LIST_HEAD(&cdev->list);