Commit 444ceed8 authored by Eric W. Biederman's avatar Eric W. Biederman Committed by Linus Torvalds
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[PATCH] proc: Factor out an instantiate method from every lookup method 



To remove the hard coded proc inode numbers it is necessary to be able to
create the proc inodes during readdir.  The instantiate methods are the subset
of lookup that is needed to accomplish that.

This first step just splits the lookup methods into 2 functions.

Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 801199ce

fs/proc/base.c

+158 −111
Original line number Diff line number Diff line
@@ -1254,21 +1254,15 @@ static struct dentry_operations tid_fd_dentry_operations = 
	.d_delete	= pid_delete_dentry,

};



/* SMP-safe */

static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)

static struct dentry *proc_fd_instantiate(struct inode *dir,

	struct dentry *dentry, struct task_struct *task, void *ptr)

{

	struct task_struct *task = get_proc_task(dir);

	unsigned fd = name_to_int(dentry);

	struct dentry *result = ERR_PTR(-ENOENT);

	unsigned fd = *(unsigned *)ptr;

	struct file *file;

	struct files_struct *files;

 	struct inode *inode;

 	struct proc_inode *ei;



	if (!task)

		goto out_no_task;

	if (fd == ~0U)

		goto out;

	struct dentry *error = ERR_PTR(-ENOENT);



	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd);

	if (!inode)
@@ -1277,7 +1271,7 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, 
	ei->fd = fd;

	files = get_files_struct(task);

	if (!files)

		goto out_unlock;

		goto out_iput;

	inode->i_mode = S_IFLNK;



	/*
@@ -1287,13 +1281,14 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, 
	spin_lock(&files->file_lock);

	file = fcheck_files(files, fd);

	if (!file)

		goto out_unlock2;

		goto out_unlock;

	if (file->f_mode & 1)

		inode->i_mode |= S_IRUSR | S_IXUSR;

	if (file->f_mode & 2)

		inode->i_mode |= S_IWUSR | S_IXUSR;

	spin_unlock(&files->file_lock);

	put_files_struct(files);



	inode->i_op = &proc_pid_link_inode_operations;

	inode->i_size = 64;

	ei->op.proc_get_link = proc_fd_link;
@@ -1301,20 +1296,37 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, 
	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (tid_fd_revalidate(dentry, NULL))

		result = NULL;

out:

	put_task_struct(task);

out_no_task:

	return result;

		error = NULL;



out_unlock2:

 out:

	return error;

out_unlock:

	spin_unlock(&files->file_lock);

	put_files_struct(files);

out_unlock:

out_iput:

	iput(inode);

	goto out;

}



/* SMP-safe */

static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)

{

	struct task_struct *task = get_proc_task(dir);

	unsigned fd = name_to_int(dentry);

	struct dentry *result = ERR_PTR(-ENOENT);



	if (!task)

		goto out_no_task;

	if (fd == ~0U)

		goto out;



	result = proc_fd_instantiate(dir, dentry, task, &fd);

out:

	put_task_struct(task);

out_no_task:

	return result;

}



static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)

{

	struct dentry *dentry = filp->f_dentry;
@@ -1395,6 +1407,36 @@ static struct inode_operations proc_fd_inode_operations = { 
	.setattr	= proc_setattr,

};



static struct dentry *proc_pident_instantiate(struct inode *dir,

	struct dentry *dentry, struct task_struct *task, void *ptr)

{

	struct pid_entry *p = ptr;

	struct inode *inode;

	struct proc_inode *ei;

	struct dentry *error = ERR_PTR(-EINVAL);



	inode = proc_pid_make_inode(dir->i_sb, task, p->type);

	if (!inode)

		goto out;



	ei = PROC_I(inode);

	inode->i_mode = p->mode;

	if (S_ISDIR(inode->i_mode))

		inode->i_nlink = 2;	/* Use getattr to fix if necessary */

	if (p->iop)

		inode->i_op = p->iop;

	if (p->fop)

		inode->i_fop = p->fop;

	ei->op = p->op;

	dentry->d_op = &pid_dentry_operations;

	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (pid_revalidate(dentry, NULL))

		error = NULL;

out:

	return error;

}



/* SMP-safe */

static struct dentry *proc_pident_lookup(struct inode *dir, 

					 struct dentry *dentry,
@@ -1404,7 +1446,6 @@ static struct dentry *proc_pident_lookup(struct inode *dir, 
	struct dentry *error;

	struct task_struct *task = get_proc_task(dir);

	struct pid_entry *p;

	struct proc_inode *ei;



	error = ERR_PTR(-ENOENT);

	inode = NULL;
@@ -1425,25 +1466,7 @@ static struct dentry *proc_pident_lookup(struct inode *dir, 
	if (!p->name)

		goto out;



	error = ERR_PTR(-EINVAL);

	inode = proc_pid_make_inode(dir->i_sb, task, p->type);

	if (!inode)

		goto out;



	ei = PROC_I(inode);

	inode->i_mode = p->mode;

	if (S_ISDIR(inode->i_mode))

		inode->i_nlink = 2;	/* Use getattr to fix if necessary */

	if (p->iop)

		inode->i_op = p->iop;

	if (p->fop)

		inode->i_fop = p->fop;

	ei->op = p->op;

	dentry->d_op = &pid_dentry_operations;

	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (pid_revalidate(dentry, NULL))

		error = NULL;

	error = proc_pident_instantiate(dir, dentry, task, p);

out:

	put_task_struct(task);

out_no_task:
@@ -1709,29 +1732,13 @@ static struct dentry_operations proc_base_dentry_operations = 
	.d_delete	= pid_delete_dentry,

};



static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)

static struct dentry *proc_base_instantiate(struct inode *dir,

	struct dentry *dentry, struct task_struct *task, void *ptr)

{

	struct pid_entry *p = ptr;

	struct inode *inode;

	struct dentry *error;

	struct task_struct *task = get_proc_task(dir);

	struct pid_entry *p;

	struct proc_inode *ei;



	error = ERR_PTR(-ENOENT);

	inode = NULL;



	if (!task)

		goto out_no_task;



	/* Lookup the directory entry */

	for (p = proc_base_stuff; p->name; p++) {

		if (p->len != dentry->d_name.len)

			continue;

		if (!memcmp(dentry->d_name.name, p->name, p->len))

			break;

	}

	if (!p->name)

		goto out;

	struct dentry *error = ERR_PTR(-EINVAL);



	/* Allocate the inode */

	error = ERR_PTR(-ENOMEM);
@@ -1767,14 +1774,41 @@ static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) 
	d_add(dentry, inode);

	error = NULL;

out:

	put_task_struct(task);

out_no_task:

	return error;

out_iput:

	iput(inode);

	goto out;

}



static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)

{

	struct dentry *error;

	struct task_struct *task = get_proc_task(dir);

	struct pid_entry *p;



	error = ERR_PTR(-ENOENT);



	if (!task)

		goto out_no_task;



	/* Lookup the directory entry */

	for (p = proc_base_stuff; p->name; p++) {

		if (p->len != dentry->d_name.len)

			continue;

		if (!memcmp(dentry->d_name.name, p->name, p->len))

			break;

	}

	if (!p->name)

		goto out;



	error = proc_base_instantiate(dir, dentry, task, p);



out:

	put_task_struct(task);

out_no_task:

	return error;

}



/*

 * Thread groups

 */
@@ -1915,12 +1949,40 @@ out: 
	return;

}



struct dentry *proc_pid_instantiate(struct inode *dir,

	struct dentry * dentry, struct task_struct *task, void *ptr)

{

	struct dentry *error = ERR_PTR(-ENOENT);

	struct inode *inode;



	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);

	if (!inode)

		goto out;



	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;

	inode->i_op = &proc_tgid_base_inode_operations;

	inode->i_fop = &proc_tgid_base_operations;

	inode->i_flags|=S_IMMUTABLE;

	inode->i_nlink = 4;

#ifdef CONFIG_SECURITY

	inode->i_nlink += 1;

#endif



	dentry->d_op = &pid_dentry_operations;



	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (pid_revalidate(dentry, NULL))

		error = NULL;

out:

	return error;

}



/* SMP-safe */

struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)

{

	struct dentry *result = ERR_PTR(-ENOENT);

	struct task_struct *task;

	struct inode *inode;

	unsigned tgid;



	result = proc_base_lookup(dir, dentry);
@@ -1939,28 +2001,7 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct 
	if (!task)

		goto out;



	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);

	if (!inode)

		goto out_put_task;



	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;

	inode->i_op = &proc_tgid_base_inode_operations;

	inode->i_fop = &proc_tgid_base_operations;

	inode->i_flags|=S_IMMUTABLE;

#ifdef CONFIG_SECURITY

	inode->i_nlink = 5;

#else

	inode->i_nlink = 4;

#endif



	dentry->d_op = &pid_dentry_operations;



	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (pid_revalidate(dentry, NULL))

		result = NULL;



out_put_task:

	result = proc_pid_instantiate(dir, dentry, task, NULL);

	put_task_struct(task);

out:

	return result;
@@ -2107,13 +2148,40 @@ static struct inode_operations proc_tid_base_inode_operations = { 
	.setattr	= proc_setattr,

};



static struct dentry *proc_task_instantiate(struct inode *dir,

	struct dentry *dentry, struct task_struct *task, void *ptr)

{

	struct dentry *error = ERR_PTR(-ENOENT);

	struct inode *inode;

	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);



	if (!inode)

		goto out;

	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;

	inode->i_op = &proc_tid_base_inode_operations;

	inode->i_fop = &proc_tid_base_operations;

	inode->i_flags|=S_IMMUTABLE;

	inode->i_nlink = 3;

#ifdef CONFIG_SECURITY

	inode->i_nlink += 1;

#endif



	dentry->d_op = &pid_dentry_operations;



	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (pid_revalidate(dentry, NULL))

		error = NULL;

out:

	return error;

}



/* SMP-safe */

static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)

{

	struct dentry *result = ERR_PTR(-ENOENT);

	struct task_struct *task;

	struct task_struct *leader = get_proc_task(dir);

	struct inode *inode;

	unsigned tid;



	if (!leader)
@@ -2133,28 +2201,7 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry 
	if (leader->tgid != task->tgid)

		goto out_drop_task;



	inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);





	if (!inode)

		goto out_drop_task;

	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;

	inode->i_op = &proc_tid_base_inode_operations;

	inode->i_fop = &proc_tid_base_operations;

	inode->i_flags|=S_IMMUTABLE;

#ifdef CONFIG_SECURITY

	inode->i_nlink = 4;

#else

	inode->i_nlink = 3;

#endif



	dentry->d_op = &pid_dentry_operations;



	d_add(dentry, inode);

	/* Close the race of the process dying before we return the dentry */

	if (pid_revalidate(dentry, NULL))

		result = NULL;



	result = proc_task_instantiate(dir, dentry, task, NULL);

out_drop_task:

	put_task_struct(task);

out:

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