drivers/char/tty_io.c | 2
fs/char_dev.c | 116 ++++++++++++++++++++++++++++++++++++--------------
fs/file_table.c | 4 +
fs/inode.c | 3 +
fs/open.c | 4 -
include/linux/cdev.h | 9 +--
include/linux/fs.h | 2
7 files changed, 99 insertions(+), 41 deletions(-)
diff -puN drivers/char/tty_io.c~T31-i_cdev-C69 drivers/char/tty_io.c
--- 25/drivers/char/tty_io.c~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/drivers/char/tty_io.c 2003-05-05 22:41:38.000000000 -0700
@@ -2167,7 +2167,7 @@ int tty_register_driver(struct tty_drive
driver->cdev.owner = driver->owner;
error = cdev_add(&driver->cdev, dev, driver->num);
if (error) {
- cdev_put(&driver->cdev);
+ kobject_del(&driver->cdev.kobj);
unregister_chrdev_region(dev, driver->num);
return error;
}
diff -puN fs/char_dev.c~T31-i_cdev-C69 fs/char_dev.c
--- 25/fs/char_dev.c~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/fs/char_dev.c 2003-05-05 22:41:38.000000000 -0700
@@ -67,27 +67,6 @@ int get_chrdev_list(char *page)
}
/*
- * Return the function table of a device, if present.
- * Load the driver if needed.
- * Increment the reference count of module in question.
- */
-static struct file_operations *get_chrfops(dev_t dev)
-{
- struct file_operations *ret = NULL;
- int index;
- struct kobject *kobj = kobj_lookup(cdev_map, dev, &index);
-
- if (kobj) {
- struct cdev *p = container_of(kobj, struct cdev, kobj);
- struct module *owner = p->owner;
- ret = fops_get(p->ops);
- cdev_put(p);
- module_put(owner);
- }
- return ret;
-}
-
-/*
* Register a single major with a specified minor range.
*
* If major == 0 this functions will dynamically allocate a major and return
@@ -238,7 +217,7 @@ int register_chrdev(unsigned int major,
return major ? 0 : cd->major;
out:
- cdev_put(cdev);
+ kobject_put(&cdev->kobj);
out2:
__unregister_chrdev_region(cd->major, 0, 256);
return err;
@@ -268,25 +247,76 @@ int unregister_chrdev(unsigned int major
return 0;
}
+static spinlock_t cdev_lock = SPIN_LOCK_UNLOCKED;
/*
* Called every time a character special file is opened
*/
int chrdev_open(struct inode * inode, struct file * filp)
{
- int ret = -ENODEV;
+ struct cdev *p;
+ struct cdev *new = NULL;
+ int ret = 0;
- filp->f_op = get_chrfops(kdev_t_to_nr(inode->i_rdev));
- if (filp->f_op) {
- ret = 0;
- if (filp->f_op->open != NULL) {
- lock_kernel();
- ret = filp->f_op->open(inode,filp);
- unlock_kernel();
- }
+ spin_lock(&cdev_lock);
+ p = inode->i_cdev;
+ if (!p) {
+ struct kobject *kobj;
+ int idx;
+ spin_unlock(&cdev_lock);
+ kobj = kobj_lookup(cdev_map, kdev_t_to_nr(inode->i_rdev), &idx);
+ if (!kobj)
+ return -ENODEV;
+ new = container_of(kobj, struct cdev, kobj);
+ spin_lock(&cdev_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))
+ ret = -ENODEV;
+ } else if (!cdev_get(p))
+ ret = -ENODEV;
+ spin_unlock(&cdev_lock);
+ cdev_put(new);
+ if (ret)
+ return ret;
+ filp->f_op = fops_get(p->ops);
+ if (!filp->f_op) {
+ cdev_put(p);
+ return -ENODEV;
}
+ if (filp->f_op->open) {
+ lock_kernel();
+ ret = filp->f_op->open(inode,filp);
+ unlock_kernel();
+ }
+ if (ret)
+ cdev_put(p);
return ret;
}
+void cd_forget(struct inode *inode)
+{
+ spin_lock(&cdev_lock);
+ list_del_init(&inode->i_devices);
+ inode->i_cdev = NULL;
+ spin_unlock(&cdev_lock);
+}
+
+void cdev_purge(struct cdev *cdev)
+{
+ spin_lock(&cdev_lock);
+ while (!list_empty(&cdev->list)) {
+ struct inode *inode;
+ inode = container_of(cdev->list.next, struct inode, i_devices);
+ list_del_init(&inode->i_devices);
+ inode->i_cdev = NULL;
+ }
+ spin_unlock(&cdev_lock);
+}
+
/*
* Dummy default file-operations: the only thing this does
* is contain the open that then fills in the correct operations
@@ -345,7 +375,7 @@ void cdev_unmap(dev_t dev, unsigned coun
void cdev_del(struct cdev *p)
{
kobject_del(&p->kobj);
- cdev_put(p);
+ kobject_put(&p->kobj);
}
struct kobject *cdev_get(struct cdev *p)
@@ -361,14 +391,33 @@ struct kobject *cdev_get(struct cdev *p)
return kobj;
}
+void cdev_put(struct cdev *p)
+{
+ if (p) {
+ kobject_put(&p->kobj);
+ module_put(p->owner);
+ }
+}
+
static decl_subsys(cdev, NULL, NULL);
+static void cdev_default_release(struct kobject *kobj)
+{
+ struct cdev *p = container_of(kobj, struct cdev, kobj);
+ cdev_purge(p);
+}
+
static void cdev_dynamic_release(struct kobject *kobj)
{
struct cdev *p = container_of(kobj, struct cdev, kobj);
+ cdev_purge(p);
kfree(p);
}
+static struct kobj_type ktype_cdev_default = {
+ .release = cdev_default_release,
+};
+
static struct kobj_type ktype_cdev_dynamic = {
.release = cdev_dynamic_release,
};
@@ -385,6 +434,7 @@ struct cdev *cdev_alloc(void)
if (p) {
memset(p, 0, sizeof(struct cdev));
p->kobj.kset = &kset_dynamic;
+ INIT_LIST_HEAD(&p->list);
kobject_init(&p->kobj);
}
return p;
@@ -392,7 +442,9 @@ struct cdev *cdev_alloc(void)
void cdev_init(struct cdev *cdev, struct file_operations *fops)
{
+ INIT_LIST_HEAD(&cdev->list);
kobj_set_kset_s(cdev, cdev_subsys);
+ cdev->kobj.ktype = &ktype_cdev_default;
kobject_init(&cdev->kobj);
cdev->ops = fops;
}
diff -puN fs/file_table.c~T31-i_cdev-C69 fs/file_table.c
--- 25/fs/file_table.c~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/fs/file_table.c 2003-05-05 22:41:38.000000000 -0700
@@ -15,7 +15,7 @@
#include <linux/security.h>
#include <linux/eventpoll.h>
#include <linux/mount.h>
-
+#include <linux/cdev.h>
/* sysctl tunables... */
struct files_stat_struct files_stat = {
@@ -166,6 +166,8 @@ void __fput(struct file *file)
if (file->f_op && file->f_op->release)
file->f_op->release(inode, file);
security_file_free(file);
+ if (unlikely(inode->i_cdev != NULL))
+ cdev_put(inode->i_cdev);
fops_put(file->f_op);
if (file->f_mode & FMODE_WRITE)
put_write_access(inode);
diff -puN fs/inode.c~T31-i_cdev-C69 fs/inode.c
--- 25/fs/inode.c~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/fs/inode.c 2003-05-05 22:41:38.000000000 -0700
@@ -128,6 +128,7 @@ static struct inode *alloc_inode(struct
memset(&inode->i_dquot, 0, sizeof(inode->i_dquot));
inode->i_pipe = NULL;
inode->i_bdev = NULL;
+ inode->i_cdev = NULL;
inode->i_rdev = to_kdev_t(0);
inode->i_security = NULL;
if (security_inode_alloc(inode)) {
@@ -241,6 +242,8 @@ void clear_inode(struct inode *inode)
inode->i_sb->s_op->clear_inode(inode);
if (inode->i_bdev)
bd_forget(inode);
+ if (inode->i_cdev)
+ cd_forget(inode);
inode->i_state = I_CLEAR;
}
diff -puN fs/open.c~T31-i_cdev-C69 fs/open.c
--- 25/fs/open.c~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/fs/open.c 2003-05-05 22:41:38.000000000 -0700
@@ -671,8 +671,8 @@ struct file *dentry_open(struct dentry *
if (f->f_flags & O_DIRECT) {
if (!inode->i_mapping || !inode->i_mapping->a_ops ||
!inode->i_mapping->a_ops->direct_IO) {
- error = -EINVAL;
- goto cleanup_all;
+ fput(f);
+ return ERR_PTR(-EINVAL);
}
}
diff -puN include/linux/cdev.h~T31-i_cdev-C69 include/linux/cdev.h
--- 25/include/linux/cdev.h~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/include/linux/cdev.h 2003-05-05 22:41:38.000000000 -0700
@@ -6,17 +6,14 @@ struct cdev {
struct kobject kobj;
struct module *owner;
struct file_operations *ops;
+ struct list_head list;
};
void cdev_init(struct cdev *, struct file_operations *);
struct cdev *cdev_alloc(void);
-static inline void cdev_put(struct cdev *p)
-{
- if (p)
- kobject_put(&p->kobj);
-}
+void cdev_put(struct cdev *p);
struct kobject *cdev_get(struct cdev *);
@@ -26,5 +23,7 @@ void cdev_del(struct cdev *);
void cdev_unmap(dev_t, unsigned);
+void cd_forget(struct inode *);
+
#endif
#endif
diff -puN include/linux/fs.h~T31-i_cdev-C69 include/linux/fs.h
--- 25/include/linux/fs.h~T31-i_cdev-C69 2003-05-05 22:41:38.000000000 -0700
+++ 25-akpm/include/linux/fs.h 2003-05-05 22:41:38.000000000 -0700
@@ -382,6 +382,8 @@ struct inode {
struct list_head i_devices;
struct pipe_inode_info *i_pipe;
struct block_device *i_bdev;
+ struct cdev *i_cdev;
+ int i_cindex;
unsigned long i_dnotify_mask; /* Directory notify events */
struct dnotify_struct *i_dnotify; /* for directory notifications */
_