proc_fill_cache(): just make instantiate_t return int

all instances always return ERR_PTR(-E...) or NULL, anyway
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/proc/base.c

@@ -1700,7 +1700,7 @@ bool proc_fill_cache(struct file *file, struct dir_context *ctx,
 		struct dentry *new;
 		new = d_alloc(dir, &qname);
 		if (new) {
-			child = instantiate(dir->d_inode, new, task, ptr);
+			child = ERR_PTR(instantiate(dir->d_inode, new, task, ptr)); 
 			if (child)
 				dput(new);
 			else
@@ -1844,7 +1844,7 @@ struct map_files_info {
 	unsigned char	name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
 };
 
-static struct dentry *
+static int
 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
 			   struct task_struct *task, const void *ptr)
 {
@@ -1854,7 +1854,7 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
 
 	inode = proc_pid_make_inode(dir->i_sb, task);
 	if (!inode)
-		return ERR_PTR(-ENOENT);
+		return -ENOENT;
 
 	ei = PROC_I(inode);
 	ei->op.proc_get_link = proc_map_files_get_link;
@@ -1871,7 +1871,7 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
 	d_set_d_op(dentry, &tid_map_files_dentry_operations);
 	d_add(dentry, inode);
 
-	return NULL;
+	return 0;
 }
 
 static struct dentry *proc_map_files_lookup(struct inode *dir,
@@ -1880,23 +1880,23 @@ static struct dentry *proc_map_files_lookup(struct inode *dir,
 	unsigned long vm_start, vm_end;
 	struct vm_area_struct *vma;
 	struct task_struct *task;
-	struct dentry *result;
+	int result;
 	struct mm_struct *mm;
 
-	result = ERR_PTR(-EPERM);
+	result = -EPERM;
 	if (!capable(CAP_SYS_ADMIN))
 		goto out;
 
-	result = ERR_PTR(-ENOENT);
+	result = -ENOENT;
 	task = get_proc_task(dir);
 	if (!task)
 		goto out;
 
-	result = ERR_PTR(-EACCES);
+	result = -EACCES;
 	if (!ptrace_may_access(task, PTRACE_MODE_READ))
 		goto out_put_task;
 
-	result = ERR_PTR(-ENOENT);
+	result = -ENOENT;
 	if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
 		goto out_put_task;
 
@@ -1919,7 +1919,7 @@ static struct dentry *proc_map_files_lookup(struct inode *dir,
 out_put_task:
 	put_task_struct(task);
 out:
-	return result;
+	return ERR_PTR(result);
 }
 
 static const struct inode_operations proc_map_files_inode_operations = {
@@ -2133,13 +2133,12 @@ static const struct file_operations proc_timers_operations = {
 };
 #endif /* CONFIG_CHECKPOINT_RESTORE */
 
-static struct dentry *proc_pident_instantiate(struct inode *dir,
+static int proc_pident_instantiate(struct inode *dir,
 	struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
 	const struct pid_entry *p = ptr;
 	struct inode *inode;
 	struct proc_inode *ei;
-	struct dentry *error = ERR_PTR(-ENOENT);
 
 	inode = proc_pid_make_inode(dir->i_sb, task);
 	if (!inode)
@@ -2158,9 +2157,9 @@ static struct dentry *proc_pident_instantiate(struct inode *dir,
 	d_add(dentry, inode);
 	/* Close the race of the process dying before we return the dentry */
 	if (pid_revalidate(dentry, 0))
-		error = NULL;
+		return 0;
 out:
-	return error;
+	return -ENOENT;
 }
 
 static struct dentry *proc_pident_lookup(struct inode *dir, 
@@ -2168,11 +2167,11 @@ static struct dentry *proc_pident_lookup(struct inode *dir,
 					 const struct pid_entry *ents,
 					 unsigned int nents)
 {
-	struct dentry *error;
+	int error;
 	struct task_struct *task = get_proc_task(dir);
 	const struct pid_entry *p, *last;
 
-	error = ERR_PTR(-ENOENT);
+	error = -ENOENT;
 
 	if (!task)
 		goto out_no_task;
@@ -2195,7 +2194,7 @@ static struct dentry *proc_pident_lookup(struct inode *dir,
 out:
 	put_task_struct(task);
 out_no_task:
-	return error;
+	return ERR_PTR(error);
 }
 
 static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
@@ -2778,11 +2777,10 @@ void proc_flush_task(struct task_struct *task)
 	}
 }
 
-static struct dentry *proc_pid_instantiate(struct inode *dir,
-					   struct dentry * dentry,
-					   struct task_struct *task, const void *ptr)
+static int proc_pid_instantiate(struct inode *dir,
+				   struct dentry * dentry,
+				   struct task_struct *task, const void *ptr)
 {
-	struct dentry *error = ERR_PTR(-ENOENT);
 	struct inode *inode;
 
 	inode = proc_pid_make_inode(dir->i_sb, task);
@@ -2802,14 +2800,14 @@ static struct dentry *proc_pid_instantiate(struct inode *dir,
 	d_add(dentry, inode);
 	/* Close the race of the process dying before we return the dentry */
 	if (pid_revalidate(dentry, 0))
-		error = NULL;
+		return 0;
 out:
-	return error;
+	return -ENOENT;
 }
 
 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
 {
-	struct dentry *result = NULL;
+	int result = 0;
 	struct task_struct *task;
 	unsigned tgid;
 	struct pid_namespace *ns;
@@ -2830,7 +2828,7 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsign
 	result = proc_pid_instantiate(dir, dentry, task, NULL);
 	put_task_struct(task);
 out:
-	return result;
+	return ERR_PTR(result);
 }
 
 /*
@@ -3025,10 +3023,9 @@ static const struct inode_operations proc_tid_base_inode_operations = {
 	.setattr	= proc_setattr,
 };
 
-static struct dentry *proc_task_instantiate(struct inode *dir,
+static int proc_task_instantiate(struct inode *dir,
 	struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
-	struct dentry *error = ERR_PTR(-ENOENT);
 	struct inode *inode;
 	inode = proc_pid_make_inode(dir->i_sb, task);
 
@@ -3047,14 +3044,14 @@ static struct dentry *proc_task_instantiate(struct inode *dir,
 	d_add(dentry, inode);
 	/* Close the race of the process dying before we return the dentry */
 	if (pid_revalidate(dentry, 0))
-		error = NULL;
+		return 0;
 out:
-	return error;
+	return -ENOENT;
 }
 
 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
 {
-	struct dentry *result = ERR_PTR(-ENOENT);
+	int result = -ENOENT;
 	struct task_struct *task;
 	struct task_struct *leader = get_proc_task(dir);
 	unsigned tid;
@@ -3084,7 +3081,7 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry
 out:
 	put_task_struct(leader);
 out_no_task:
-	return result;
+	return ERR_PTR(result);
 }
 
 /*

fs/proc/fd.c

@@ -167,11 +167,10 @@ static int proc_fd_link(struct dentry *dentry, struct path *path)
 	return ret;
 }
 
-static struct dentry *
+static int
 proc_fd_instantiate(struct inode *dir, struct dentry *dentry,
 		    struct task_struct *task, const void *ptr)
 {
-	struct dentry *error = ERR_PTR(-ENOENT);
 	unsigned fd = (unsigned long)ptr;
 	struct proc_inode *ei;
 	struct inode *inode;
@@ -194,9 +193,9 @@ proc_fd_instantiate(struct inode *dir, struct dentry *dentry,
 
 	/* Close the race of the process dying before we return the dentry */
 	if (tid_fd_revalidate(dentry, 0))
-		error = NULL;
+		return 0;
  out:
-	return error;
+	return -ENOENT;
 }
 
 static struct dentry *proc_lookupfd_common(struct inode *dir,
@@ -204,7 +203,7 @@ static struct dentry *proc_lookupfd_common(struct inode *dir,
 					   instantiate_t instantiate)
 {
 	struct task_struct *task = get_proc_task(dir);
-	struct dentry *result = ERR_PTR(-ENOENT);
+	int result = -ENOENT;
 	unsigned fd = name_to_int(dentry);
 
 	if (!task)
@@ -216,7 +215,7 @@ static struct dentry *proc_lookupfd_common(struct inode *dir,
 out:
 	put_task_struct(task);
 out_no_task:
-	return result;
+	return ERR_PTR(result);
 }
 
 static int proc_readfd_common(struct file *file, struct dir_context *ctx,
@@ -300,11 +299,10 @@ const struct inode_operations proc_fd_inode_operations = {
 	.setattr	= proc_setattr,
 };
 
-static struct dentry *
+static int
 proc_fdinfo_instantiate(struct inode *dir, struct dentry *dentry,
 			struct task_struct *task, const void *ptr)
 {
-	struct dentry *error = ERR_PTR(-ENOENT);
 	unsigned fd = (unsigned long)ptr;
 	struct proc_inode *ei;
 	struct inode *inode;
@@ -324,9 +322,9 @@ proc_fdinfo_instantiate(struct inode *dir, struct dentry *dentry,
 
 	/* Close the race of the process dying before we return the dentry */
 	if (tid_fd_revalidate(dentry, 0))
-		error = NULL;
+		return 0;
  out:
-	return error;
+	return -ENOENT;
 }
 
 static struct dentry *

fs/proc/internal.h

@@ -170,7 +170,7 @@ extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned
 extern loff_t mem_lseek(struct file *, loff_t, int);
 
 /* Lookups */
-typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
+typedef int instantiate_t(struct inode *, struct dentry *,
 				     struct task_struct *, const void *);
 extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int,
 			   instantiate_t, struct task_struct *, const void *);

fs/proc/namespaces.c

@@ -187,13 +187,12 @@ static const struct inode_operations proc_ns_link_inode_operations = {
 	.setattr	= proc_setattr,
 };
 
-static struct dentry *proc_ns_instantiate(struct inode *dir,
+static int proc_ns_instantiate(struct inode *dir,
 	struct dentry *dentry, struct task_struct *task, const void *ptr)
 {
 	const struct proc_ns_operations *ns_ops = ptr;
 	struct inode *inode;
 	struct proc_inode *ei;
-	struct dentry *error = ERR_PTR(-ENOENT);
 
 	inode = proc_pid_make_inode(dir->i_sb, task);
 	if (!inode)
@@ -208,9 +207,9 @@ static struct dentry *proc_ns_instantiate(struct inode *dir,
 	d_add(dentry, inode);
 	/* Close the race of the process dying before we return the dentry */
 	if (pid_revalidate(dentry, 0))
-		error = NULL;
+		return 0;
 out:
-	return error;
+	return -ENOENT;
 }
 
 static int proc_ns_dir_readdir(struct file *file, struct dir_context *ctx)
@@ -248,12 +247,12 @@ const struct file_operations proc_ns_dir_operations = {
 static struct dentry *proc_ns_dir_lookup(struct inode *dir,
 				struct dentry *dentry, unsigned int flags)
 {
-	struct dentry *error;
+	int error;
 	struct task_struct *task = get_proc_task(dir);
 	const struct proc_ns_operations **entry, **last;
 	unsigned int len = dentry->d_name.len;
 
-	error = ERR_PTR(-ENOENT);
+	error = -ENOENT;
 
 	if (!task)
 		goto out_no_task;
@@ -272,7 +271,7 @@ static struct dentry *proc_ns_dir_lookup(struct inode *dir,
 out:
 	put_task_struct(task);
 out_no_task:
-	return error;
+	return ERR_PTR(error);
 }
 
 const struct inode_operations proc_ns_dir_inode_operations = {