[PATCH RFC 01/16] proc: drop the compat file operations

@@ -445,10 +445,6 @@ static void pde_set_flags(struct proc_dir_entry *pde)
 		pde->flags |= PROC_ENTRY_PERMANENT;
 	if (proc_ops->proc_read_iter)
 		pde->flags |= PROC_ENTRY_proc_read_iter;
-#ifdef CONFIG_COMPAT
-	if (proc_ops->proc_compat_ioctl)
-		pde->flags |= PROC_ENTRY_proc_compat_ioctl;
-#endif
 	if (proc_ops->proc_lseek)
 		pde->flags |= PROC_ENTRY_proc_lseek;
 }

@@ -410,6 +410,8 @@ static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned
 	}
 	return rv;
 }
+#else
+#define proc_reg_compat_ioctl NULL
 #endif
 
 static int pde_mmap(struct proc_dir_entry *pde, struct file *file, struct vm_area_struct *vma)

@@ -569,6 +571,7 @@ static const struct file_operations proc_reg_file_ops = {
 	.write		= proc_reg_write,
 	.poll		= proc_reg_poll,
 	.unlocked_ioctl	= proc_reg_unlocked_ioctl,
+	.compat_ioctl	= proc_reg_compat_ioctl,
 	.mmap		= proc_reg_mmap,
 	.get_unmapped_area = proc_reg_get_unmapped_area,
 #ifndef CONFIG_MMU

@@ -585,39 +588,6 @@ static const struct file_operations proc_iter_file_ops = {
 	.splice_read	= copy_splice_read,
 	.poll		= proc_reg_poll,
 	.unlocked_ioctl	= proc_reg_unlocked_ioctl,
-	.mmap		= proc_reg_mmap,
-	.get_unmapped_area = proc_reg_get_unmapped_area,
-#ifndef CONFIG_MMU
-	.mmap_capabilities = proc_reg_mmap_capabilities,
-#endif
-	.open		= proc_reg_open,
-	.release	= proc_reg_release,
-};
-
-#ifdef CONFIG_COMPAT
-static const struct file_operations proc_reg_file_ops_compat = {
-	.llseek		= proc_reg_llseek,
-	.read		= proc_reg_read,
-	.write		= proc_reg_write,
-	.poll		= proc_reg_poll,
-	.unlocked_ioctl	= proc_reg_unlocked_ioctl,
-	.compat_ioctl	= proc_reg_compat_ioctl,
-	.mmap		= proc_reg_mmap,
-	.get_unmapped_area = proc_reg_get_unmapped_area,
-#ifndef CONFIG_MMU
-	.mmap_capabilities = proc_reg_mmap_capabilities,
-#endif
-	.open		= proc_reg_open,
-	.release	= proc_reg_release,
-};
-
-static const struct file_operations proc_iter_file_ops_compat = {
-	.llseek		= proc_reg_llseek,
-	.read_iter	= proc_reg_read_iter,
-	.splice_read	= copy_splice_read,
-	.write		= proc_reg_write,
-	.poll		= proc_reg_poll,
-	.unlocked_ioctl	= proc_reg_unlocked_ioctl,
 	.compat_ioctl	= proc_reg_compat_ioctl,
 	.mmap		= proc_reg_mmap,
 	.get_unmapped_area = proc_reg_get_unmapped_area,

@@ -627,7 +597,6 @@ static const struct file_operations proc_iter_file_ops_compat = {
 	.open		= proc_reg_open,
 	.release	= proc_reg_release,
 };
-#endif
 
 static const char *proc_get_link(struct dentry *dentry,
 				 struct inode *inode,

@@ -683,14 +652,6 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
 			inode->i_fop = &proc_iter_file_ops;
 		else
 			inode->i_fop = &proc_reg_file_ops;
-#ifdef CONFIG_COMPAT
-		if (pde_has_proc_compat_ioctl(de)) {
-			if (pde_has_proc_read_iter(de))
-				inode->i_fop = &proc_iter_file_ops_compat;
-			else
-				inode->i_fop = &proc_reg_file_ops_compat;
-		}
-#endif
 	} else if (S_ISDIR(inode->i_mode)) {
 		inode->i_op = de->proc_iops;
 		inode->i_fop = de->proc_dir_ops;

@@ -92,15 +92,6 @@ static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde)
 	return pde->flags & PROC_ENTRY_proc_read_iter;
 }
 
-static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde)
-{
-#ifdef CONFIG_COMPAT
-	return pde->flags & PROC_ENTRY_proc_compat_ioctl;
-#else
-	return false;
-#endif
-}
-
 static inline bool pde_has_proc_lseek(const struct proc_dir_entry *pde)
 {
 	return pde->flags & PROC_ENTRY_proc_lseek;

@@ -26,7 +26,6 @@ enum {
 #endif
 
 	PROC_ENTRY_proc_read_iter	= 1U << 1,
-	PROC_ENTRY_proc_compat_ioctl	= 1U << 2,
 	PROC_ENTRY_proc_lseek		= 1U << 3,
 
 	PROC_ENTRY_FORCE_LOOKUP		= 1U << 7,