[PATCH] type safe(r) list_entry repacement: container_of

Define container_of which cast from member to struct with some type checking.

This is much like list_entry but is cearly for things other than lists.

List_entry now uses container_of.

drivers/pci/pci-driver.c

@@ -41,8 +41,8 @@ static int pci_device_probe(struct device * dev)
 	struct pci_driver *drv;
 	struct pci_dev *pci_dev;
 
-	drv = list_entry(dev->driver, struct pci_driver, driver);
-	pci_dev = list_entry(dev, struct pci_dev, dev);
+	drv = to_pci_driver(dev->driver);
+	pci_dev = to_pci_dev(dev);
 
 	if (drv->probe) {
 		const struct pci_device_id *id;
@@ -60,7 +60,7 @@ static int pci_device_probe(struct device * dev)
 
 static int pci_device_remove(struct device * dev)
 {
-	struct pci_dev * pci_dev = list_entry(dev,struct pci_dev,dev);
+	struct pci_dev * pci_dev = to_pci_dev(dev);
 	struct pci_driver * drv = pci_dev->driver;
 
 	if (drv) {
@@ -73,7 +73,7 @@ static int pci_device_remove(struct device * dev)
 
 static int pci_device_suspend(struct device * dev, u32 state, u32 level)
 {
-	struct pci_dev * pci_dev = (struct pci_dev *)list_entry(dev,struct pci_dev,dev);
+	struct pci_dev * pci_dev = to_pci_dev(dev);
 	int error = 0;
 
 	if (pci_dev->driver) {
@@ -87,7 +87,7 @@ static int pci_device_suspend(struct device * dev, u32 state, u32 level)
 
 static int pci_device_resume(struct device * dev, u32 level)
 {
-	struct pci_dev * pci_dev = (struct pci_dev *)list_entry(dev,struct pci_dev,dev);
+	struct pci_dev * pci_dev = to_pci_dev(dev);
 
 	if (pci_dev->driver) {
 		if (level == RESUME_POWER_ON && pci_dev->driver->resume)
@@ -175,8 +175,8 @@ pci_dev_driver(const struct pci_dev *dev)
  */
 static int pci_bus_match(struct device * dev, struct device_driver * drv) 
 {
-	struct pci_dev * pci_dev = list_entry(dev, struct pci_dev, dev);
-	struct pci_driver * pci_drv = list_entry(drv,struct pci_driver,driver);
+	struct pci_dev * pci_dev = to_pci_dev(dev);
+	struct pci_driver * pci_drv = to_pci_driver(drv);
 	const struct pci_device_id * ids = pci_drv->id_table;
 
 	if (!ids) 

drivers/pci/proc.c

@@ -374,7 +374,7 @@ static struct proc_dir_entry *proc_bus_pci_dir;
 /* driverfs files */
 static ssize_t pci_show_irq(struct device * dev, char * buf, size_t count, loff_t off)
 {
-	struct pci_dev * pci_dev = list_entry(dev,struct pci_dev,dev);
+	struct pci_dev * pci_dev = to_pci_dev(dev);
 	return off ? 0 : sprintf(buf,"%u\n",pci_dev->irq);
 }
 
@@ -386,7 +386,7 @@ static struct driver_file_entry pci_irq_entry = {
 
 static ssize_t pci_show_resources(struct device * dev, char * buf, size_t count, loff_t off)
 {
-	struct pci_dev * pci_dev = list_entry(dev,struct pci_dev,dev);
+	struct pci_dev * pci_dev = to_pci_dev(dev);
 	char * str = buf;
 	int i;
 

drivers/scsi/scsi.h

@@ -627,6 +627,8 @@ struct scsi_device {
 	int allow_revalidate;
 	struct device sdev_driverfs_dev;
 };
+#define	to_scsi_device(d)	\
+	container_of(d, struct scsi_device, sdev_driverfs_dev)
 
 
 /*

drivers/scsi/scsi_scan.c

@@ -293,8 +293,7 @@ static int scsilun_to_int(ScsiLun *scsilun_pnt)
 static ssize_t scsi_device_type_read(struct device *driverfs_dev, char *page, 
 	size_t count, loff_t off)
 {
-	struct scsi_device *SDpnt = list_entry(driverfs_dev,
-		struct scsi_device, sdev_driverfs_dev);
+	struct scsi_device *SDpnt = to_scsi_device(driverfs_dev);
 
 	if ((SDpnt->type <= MAX_SCSI_DEVICE_CODE) && 
 		(scsi_device_types[(int)SDpnt->type] != NULL))

drivers/usb/core/usb.c

@@ -832,7 +832,7 @@ show_config (struct device *dev, char *buf, size_t count, loff_t off)
 
 	if (off)
 		return 0;
-	udev = list_entry (dev, struct usb_device, dev);
+	udev = to_usb_device (dev);
 	return sprintf (buf, "%u\n", udev->actconfig->bConfigurationValue);
 }
 static struct driver_file_entry usb_config_entry = {
@@ -851,7 +851,7 @@ show_altsetting (struct device *dev, char *buf, size_t count, loff_t off)
 
 	if (off)
 		return 0;
-	interface = list_entry (dev, struct usb_interface, dev);
+	interface = to_usb_interface (dev);
 	return sprintf (buf, "%u\n", interface->altsetting->bAlternateSetting);
 }
 static struct driver_file_entry usb_altsetting_entry = {
@@ -868,7 +868,7 @@ static ssize_t show_product (struct device *dev, char *buf, size_t count, loff_t
 
 	if (off)
 		return 0;
-	udev = list_entry (dev, struct usb_device, dev);
+	udev = to_usb_device (dev);
 
 	len = usb_string(udev, udev->descriptor.iProduct, buf, PAGE_SIZE); 
 	buf[len] = '\n';
@@ -890,7 +890,7 @@ show_manufacturer (struct device *dev, char *buf, size_t count, loff_t off)
 
 	if (off)
 		return 0;
-	udev = list_entry (dev, struct usb_device, dev);
+	udev = to_usb_device (dev);
 
 	len = usb_string(udev, udev->descriptor.iManufacturer, buf, PAGE_SIZE); 
 	buf[len] = '\n';
@@ -912,7 +912,7 @@ show_serial (struct device *dev, char *buf, size_t count, loff_t off)
 
 	if (off)
 		return 0;
-	udev = list_entry (dev, struct usb_device, dev);
+	udev = to_usb_device (dev);
 
 	len = usb_string(udev, udev->descriptor.iSerialNumber, buf, PAGE_SIZE); 
 	buf[len] = '\n';

fs/driverfs/inode.c

@@ -267,7 +267,7 @@ driverfs_read_file(struct file *file, char *buf, size_t count, loff_t *ppos)
 	if (count > PAGE_SIZE)
 		count = PAGE_SIZE;
 
-	dev = list_entry(entry->parent,struct device, dir);
+	dev = to_device(entry->parent);
 
 	page = (unsigned char*)__get_free_page(GFP_KERNEL);
 	if (!page)
@@ -328,7 +328,7 @@ driverfs_write_file(struct file *file, const char *buf, size_t count, loff_t *pp
 	if (!entry->store)
 		return 0;
 
-	dev = list_entry(entry->parent,struct device, dir);
+	dev = to_device(entry->parent);
 
 	page = (char *)__get_free_page(GFP_KERNEL);
 	if (!page)
@@ -394,7 +394,7 @@ static int driverfs_open_file(struct inode * inode, struct file * filp)
 	entry = (struct driver_file_entry *)inode->u.generic_ip;
 	if (!entry)
 		return -EFAULT;
-	dev = (struct device *)list_entry(entry->parent,struct device,dir);
+	dev = to_device(entry->parent);
 	get_device(dev);
 	filp->private_data = entry;
 	return 0;
@@ -408,7 +408,7 @@ static int driverfs_release(struct inode * inode, struct file * filp)
 	entry = (struct driver_file_entry *)filp->private_data;
 	if (!entry)
 		return -EFAULT;
-	dev = (struct device *)list_entry(entry->parent,struct device,dir);
+	dev = to_device(entry->parent);
 	put_device(dev);
 	return 0;
 }

fs/ext2/ext2.h

@@ -34,7 +34,7 @@ struct ext2_inode_info {
 
 static inline struct ext2_inode_info *EXT2_I(struct inode *inode)
 {
-	return list_entry(inode, struct ext2_inode_info, vfs_inode);
+	return container_of(inode, struct ext2_inode_info, vfs_inode);
 }
 
 /* balloc.c */

include/linux/adfs_fs.h

@@ -68,7 +68,7 @@ static inline struct adfs_sb_info *ADFS_SB(struct super_block *sb)
 
 static inline struct adfs_inode_info *ADFS_I(struct inode *inode)
 {
-	return list_entry(inode, struct adfs_inode_info, vfs_inode);
+	return container_of(inode, struct adfs_inode_info, vfs_inode);
 }
 
 #endif

include/linux/device.h

@@ -160,6 +160,8 @@ struct device {
 	void	(*release)(struct device * dev);
 };
 
+#define to_device(d) container_of(d, struct device, dir)
+
 static inline struct device *
 list_to_dev(struct list_head *node)
 {

include/linux/efs_fs.h

@@ -41,7 +41,7 @@ static const char cprt[] = "EFS: "EFS_VERSION" - (c) 1999 Al Smith <Al.Smith@aes
 
 static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
 {
-	return list_entry(inode, struct efs_inode_info, vfs_inode);
+	return container_of(inode, struct efs_inode_info, vfs_inode);
 }
 
 static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)

include/linux/ext3_fs.h

@@ -447,7 +447,7 @@ struct ext3_super_block {
 #define EXT3_SB(sb)	(&((sb)->u.ext3_sb))
 static inline struct ext3_inode_info *EXT3_I(struct inode *inode)
 {
-	return list_entry(inode, struct ext3_inode_info, vfs_inode);
+	return container_of(inode, struct ext3_inode_info, vfs_inode);
 }
 #else
 /* Assume that user mode programs are passing in an ext3fs superblock, not

include/linux/fs.h

@@ -412,12 +412,12 @@ struct socket_alloc {
 
 static inline struct socket *SOCKET_I(struct inode *inode)
 {
-	return &list_entry(inode, struct socket_alloc, vfs_inode)->socket;
+	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
 }
 
 static inline struct inode *SOCK_INODE(struct socket *socket)
 {
-	return &list_entry(socket, struct socket_alloc, socket)->vfs_inode;
+	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
 }
 
 /* will die */

include/linux/hfs_fs.h

@@ -322,7 +322,7 @@ extern void hfs_tolower(unsigned char *, int);
 
 static inline struct hfs_inode_info *HFS_I(struct inode *inode)
 {
-	return list_entry(inode, struct hfs_inode_info, vfs_inode);
+	return container_of(inode, struct hfs_inode_info, vfs_inode);
 }
 
 static inline struct hfs_sb_info *HFS_SB(struct super_block *sb)

include/linux/iso_fs.h

@@ -179,7 +179,7 @@ static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb)
 
 static inline struct iso_inode_info *ISOFS_I(struct inode *inode)
 {
-	return list_entry(inode, struct iso_inode_info, vfs_inode);
+	return container_of(inode, struct iso_inode_info, vfs_inode);
 }
 
 static inline int isonum_711(char *p)

include/linux/kernel.h

@@ -150,6 +150,19 @@ extern const char *print_tainted(void);
 #define max_t(type,x,y) \
 	({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
 
+
+/**
+ * container_of - cast a member of a structure out to the containing structure
+ *
+ * @ptr:	the pointer to the member.
+ * @type:	the type of the container struct this is embedded in.
+ * @member:	the name of the member within the struct.
+ *
+ */
+#define container_of(ptr, type, member) ({			\
+        const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
+        (type *)( (char *)__mptr - offsetof(type,member) );})
+
 #endif /* __KERNEL__ */
 
 #define SI_LOAD_SHIFT	16

include/linux/list.h

@@ -184,7 +184,7 @@ static inline void list_splice_init(list_t *list, list_t *head)
  * @member:	the name of the list_struct within the struct.
  */
 #define list_entry(ptr, type, member) \
-	((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
+	container_of(ptr, type, member)
 
 /**
  * list_for_each	-	iterate over a list

include/linux/msdos_fs.h

@@ -198,7 +198,7 @@ static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
 
 static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
 {
-	return list_entry(inode, struct msdos_inode_info, vfs_inode);
+	return container_of(inode, struct msdos_inode_info, vfs_inode);
 }
 
 struct fat_cache {

include/linux/ncp_fs.h

@@ -199,7 +199,7 @@ static inline struct ncp_server *NCP_SBP(struct super_block *sb)
 #define NCP_SERVER(inode)	NCP_SBP((inode)->i_sb)
 static inline struct ncp_inode_info *NCP_FINFO(struct inode *inode)
 {
-	return list_entry(inode, struct ncp_inode_info, vfs_inode);
+	return container_of(inode, struct ncp_inode_info, vfs_inode);
 }
 
 #ifdef DEBUG_NCP_MALLOC

include/linux/nfs_fs.h

@@ -176,7 +176,7 @@ struct nfs_inode {
 
 static inline struct nfs_inode *NFS_I(struct inode *inode)
 {
-	return list_entry(inode, struct nfs_inode, vfs_inode);
+	return container_of(inode, struct nfs_inode, vfs_inode);
 }
 #define NFS_SB(s)		((struct nfs_server *)(s->u.generic_sbp))
 

include/linux/pci.h

@@ -392,6 +392,7 @@ struct pci_dev {
 
 #define pci_dev_g(n) list_entry(n, struct pci_dev, global_list)
 #define pci_dev_b(n) list_entry(n, struct pci_dev, bus_list)
+#define	to_pci_dev(n) container_of(n, struct pci_dev, dev)
 
 /*
  *  For PCI devices, the region numbers are assigned this way:
@@ -491,6 +492,8 @@ struct pci_driver {
 	struct device_driver	driver;
 };
 
+#define	to_pci_driver(drv) container_of(drv,struct pci_driver, driver)
+
 
 /* these external functions are only available when PCI support is enabled */
 #ifdef CONFIG_PCI

include/linux/proc_fs.h

@@ -219,7 +219,7 @@ struct proc_inode {
 
 static inline struct proc_inode *PROC_I(const struct inode *inode)
 {
-	return list_entry(inode, struct proc_inode, vfs_inode);
+	return container_of(inode, struct proc_inode, vfs_inode);
 }
 
 static inline struct proc_dir_entry *PDE(const struct inode *inode)

include/linux/qnx4_fs.h

@@ -140,7 +140,7 @@ static inline struct qnx4_sb_info *qnx4_sb(struct super_block *sb)
 
 static inline struct qnx4_inode_info *qnx4_i(struct inode *inode)
 {
-	return list_entry(inode, struct qnx4_inode_info, vfs_inode);
+	return container_of(inode, struct qnx4_inode_info, vfs_inode);
 }
 
 static inline struct qnx4_inode_entry *qnx4_raw_inode(struct inode *inode)

include/linux/reiserfs_fs.h

@@ -288,7 +288,7 @@ struct unfm_nodeinfo {
 
 static inline struct reiserfs_inode_info *REISERFS_I(struct inode *inode)
 {
-	return list_entry(inode, struct reiserfs_inode_info, vfs_inode);
+	return container_of(inode, struct reiserfs_inode_info, vfs_inode);
 }
 
 static inline struct reiserfs_sb_info *REISERFS_SB(const struct super_block *sb)

include/linux/shmem_fs.h

@@ -31,7 +31,7 @@ struct shmem_sb_info {
 
 static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
 {
-	return list_entry(inode, struct shmem_inode_info, vfs_inode);
+	return container_of(inode, struct shmem_inode_info, vfs_inode);
 }
 
 #endif

include/linux/smb_fs.h

@@ -38,7 +38,7 @@ static inline struct smb_sb_info *SMB_SB(struct super_block *sb)
 
 static inline struct smb_inode_info *SMB_I(struct inode *inode)
 {
-	return list_entry(inode, struct smb_inode_info, vfs_inode);
+	return container_of(inode, struct smb_inode_info, vfs_inode);
 }
 
 /* macro names are short for word, double-word, long value (?) */

include/linux/ufs_fs.h

@@ -784,7 +784,7 @@ extern void ufs_truncate (struct inode *);
 
 static inline struct ufs_inode_info *UFS_I(struct inode *inode)
 {
-	return list_entry(inode, struct ufs_inode_info, vfs_inode);
+	return container_of(inode, struct ufs_inode_info, vfs_inode);
 }
 
 #endif	/* __KERNEL__ */

include/linux/usb.h

@@ -257,6 +257,7 @@ struct usb_interface {
 	struct device dev;		/* interface specific device info */
 	void *private_data;
 };
+#define	to_usb_interface(d) container_of(d, struct usb_interface, dev)
 
 /* USB_DT_CONFIG: Configuration descriptor information.
  *
@@ -422,6 +423,7 @@ struct usb_device {
 	int maxchild;			/* Number of ports if hub */
 	struct usb_device *children[USB_MAXCHILDREN];
 };
+#define	to_usb_device(d) container_of(d, struct usb_device, dev)
 
 extern struct usb_device *usb_alloc_dev(struct usb_device *parent, struct usb_bus *);
 extern struct usb_device *usb_get_dev(struct usb_device *dev);

net/socket.c

@@ -288,7 +288,7 @@ static struct inode *sock_alloc_inode(struct super_block *sb)
 static void sock_destroy_inode(struct inode *inode)
 {
 	kmem_cache_free(sock_inode_cachep,
-			list_entry(inode, struct socket_alloc, vfs_inode));
+			container_of(inode, struct socket_alloc, vfs_inode));
 }
 
 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)