drivers/infiniband/hw/ipath/ipath_fs.c - kernel/skids - Git at Google

 /*
  * Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved.
  * Copyright (c) 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * OpenIB.org BSD license below:
  *
  *     Redistribution and use in source and binary forms, with or
  *     without modification, are permitted provided that the following
  *     conditions are met:
  *
  *      - Redistributions of source code must retain the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer.
  *
  *      - Redistributions in binary form must reproduce the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer in the documentation and/or other materials
  *        provided with the distribution.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/mount.h>
 #include <linux/pagemap.h>
 #include <linux/init.h>
 #include <linux/namei.h>
 #include <linux/slab.h>

 #include "ipath_kernel.h"

 #define IPATHFS_MAGIC 0x726a77

 static struct super_block *ipath_super;

 static int ipathfs_mknod(struct inode *dir, struct dentry *dentry,
 			 int mode, const struct file_operations *fops,
 			 void *data)
 {
 	int error;
 	struct inode *inode = new_inode(dir->i_sb);

 	if (!inode) {
 		error = -EPERM;
 		goto bail;
 	}

 	inode->i_mode = mode;
 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 	inode->i_private = data;
 	if ((mode & S_IFMT) == S_IFDIR) {
 		inode->i_op = &simple_dir_inode_operations;
 		inc_nlink(inode);
 		inc_nlink(dir);
 	}

 	inode->i_fop = fops;

 	d_instantiate(dentry, inode);
 	error = 0;

 bail:
 	return error;
 }

 static int create_file(const char *name, mode_t mode,
 		       struct dentry *parent, struct dentry **dentry,
 		       const struct file_operations *fops, void *data)
 {
 	int error;

 	*dentry = NULL;
 	mutex_lock(&parent->d_inode->i_mutex);
 	*dentry = lookup_one_len(name, parent, strlen(name));
 	if (!IS_ERR(*dentry))
 		error = ipathfs_mknod(parent->d_inode, *dentry,
 				      mode, fops, data);
 	else
 		error = PTR_ERR(dentry);
 	mutex_unlock(&parent->d_inode->i_mutex);

 	return error;
 }

 static ssize_t atomic_stats_read(struct file *file, char __user *buf,
 				 size_t count, loff_t *ppos)
 {
 	return simple_read_from_buffer(buf, count, ppos, &ipath_stats,
 				       sizeof ipath_stats);
 }

 static const struct file_operations atomic_stats_ops = {
 	.read = atomic_stats_read,
 };

 static ssize_t atomic_counters_read(struct file *file, char __user *buf,
 				    size_t count, loff_t *ppos)
 {
 	struct infinipath_counters counters;
 	struct ipath_devdata *dd;

 	dd = file->f_path.dentry->d_inode->i_private;
 	dd->ipath_f_read_counters(dd, &counters);

 	return simple_read_from_buffer(buf, count, ppos, &counters,
 				       sizeof counters);
 }

 static const struct file_operations atomic_counters_ops = {
 	.read = atomic_counters_read,
 };

 static ssize_t flash_read(struct file *file, char __user *buf,
 			  size_t count, loff_t *ppos)
 {
 	struct ipath_devdata *dd;
 	ssize_t ret;
 	loff_t pos;
 	char *tmp;

 	pos = *ppos;

 	if ( pos < 0) {
 		ret = -EINVAL;
 		goto bail;
 	}

 	if (pos >= sizeof(struct ipath_flash)) {
 		ret = 0;
 		goto bail;
 	}

 	if (count > sizeof(struct ipath_flash) - pos)
 		count = sizeof(struct ipath_flash) - pos;

 	tmp = kmalloc(count, GFP_KERNEL);
 	if (!tmp) {
 		ret = -ENOMEM;
 		goto bail;
 	}

 	dd = file->f_path.dentry->d_inode->i_private;
 	if (ipath_eeprom_read(dd, pos, tmp, count)) {
 		ipath_dev_err(dd, "failed to read from flash\n");
 		ret = -ENXIO;
 		goto bail_tmp;
 	}

 	if (copy_to_user(buf, tmp, count)) {
 		ret = -EFAULT;
 		goto bail_tmp;
 	}

 	*ppos = pos + count;
 	ret = count;

 bail_tmp:
 	kfree(tmp);

 bail:
 	return ret;
 }

 static ssize_t flash_write(struct file *file, const char __user *buf,
 			   size_t count, loff_t *ppos)
 {
 	struct ipath_devdata *dd;
 	ssize_t ret;
 	loff_t pos;
 	char *tmp;

 	pos = *ppos;

 	if (pos != 0) {
 		ret = -EINVAL;
 		goto bail;
 	}

 	if (count != sizeof(struct ipath_flash)) {
 		ret = -EINVAL;
 		goto bail;
 	}

 	tmp = kmalloc(count, GFP_KERNEL);
 	if (!tmp) {
 		ret = -ENOMEM;
 		goto bail;
 	}

 	if (copy_from_user(tmp, buf, count)) {
 		ret = -EFAULT;
 		goto bail_tmp;
 	}

 	dd = file->f_path.dentry->d_inode->i_private;
 	if (ipath_eeprom_write(dd, pos, tmp, count)) {
 		ret = -ENXIO;
 		ipath_dev_err(dd, "failed to write to flash\n");
 		goto bail_tmp;
 	}

 	*ppos = pos + count;
 	ret = count;

 bail_tmp:
 	kfree(tmp);

 bail:
 	return ret;
 }

 static const struct file_operations flash_ops = {
 	.read = flash_read,
 	.write = flash_write,
 };

 static int create_device_files(struct super_block *sb,
 			       struct ipath_devdata *dd)
 {
 	struct dentry *dir, *tmp;
 	char unit[10];
 	int ret;

 	snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
 	ret = create_file(unit, S_IFDIR|S_IRUGO|S_IXUGO, sb->s_root, &dir,
 			  &simple_dir_operations, dd);
 	if (ret) {
 		printk(KERN_ERR "create_file(%s) failed: %d\n", unit, ret);
 		goto bail;
 	}

 	ret = create_file("atomic_counters", S_IFREG|S_IRUGO, dir, &tmp,
 			  &atomic_counters_ops, dd);
 	if (ret) {
 		printk(KERN_ERR "create_file(%s/atomic_counters) "
 		       "failed: %d\n", unit, ret);
 		goto bail;
 	}

 	ret = create_file("flash", S_IFREG|S_IWUSR|S_IRUGO, dir, &tmp,
 			  &flash_ops, dd);
 	if (ret) {
 		printk(KERN_ERR "create_file(%s/flash) "
 		       "failed: %d\n", unit, ret);
 		goto bail;
 	}

 bail:
 	return ret;
 }

 static int remove_file(struct dentry *parent, char *name)
 {
 	struct dentry *tmp;
 	int ret;

 	tmp = lookup_one_len(name, parent, strlen(name));

 	if (IS_ERR(tmp)) {
 		ret = PTR_ERR(tmp);
 		goto bail;
 	}

 	spin_lock(&dcache_lock);
 	spin_lock(&tmp->d_lock);
 	if (!(d_unhashed(tmp) && tmp->d_inode)) {
 		dget_locked(tmp);
 		__d_drop(tmp);
 		spin_unlock(&tmp->d_lock);
 		spin_unlock(&dcache_lock);
 		simple_unlink(parent->d_inode, tmp);
 	} else {
 		spin_unlock(&tmp->d_lock);
 		spin_unlock(&dcache_lock);
 	}

 	ret = 0;
 bail:
 	/*
 	 * We don't expect clients to care about the return value, but
 	 * it's there if they need it.
 	 */
 	return ret;
 }

 static int remove_device_files(struct super_block *sb,
 			       struct ipath_devdata *dd)
 {
 	struct dentry *dir, *root;
 	char unit[10];
 	int ret;

 	root = dget(sb->s_root);
 	mutex_lock(&root->d_inode->i_mutex);
 	snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
 	dir = lookup_one_len(unit, root, strlen(unit));

 	if (IS_ERR(dir)) {
 		ret = PTR_ERR(dir);
 		printk(KERN_ERR "Lookup of %s failed\n", unit);
 		goto bail;
 	}

 	remove_file(dir, "flash");
 	remove_file(dir, "atomic_counters");
 	d_delete(dir);
 	ret = simple_rmdir(root->d_inode, dir);

 bail:
 	mutex_unlock(&root->d_inode->i_mutex);
 	dput(root);
 	return ret;
 }

 static int ipathfs_fill_super(struct super_block *sb, void *data,
 			      int silent)
 {
 	struct ipath_devdata *dd, *tmp;
 	unsigned long flags;
 	int ret;

 	static struct tree_descr files[] = {
 		[2] = {"atomic_stats", &atomic_stats_ops, S_IRUGO},
 		{""},
 	};

 	ret = simple_fill_super(sb, IPATHFS_MAGIC, files);
 	if (ret) {
 		printk(KERN_ERR "simple_fill_super failed: %d\n", ret);
 		goto bail;
 	}

 	spin_lock_irqsave(&ipath_devs_lock, flags);

 	list_for_each_entry_safe(dd, tmp, &ipath_dev_list, ipath_list) {
 		spin_unlock_irqrestore(&ipath_devs_lock, flags);
 		ret = create_device_files(sb, dd);
 		if (ret)
 			goto bail;
 		spin_lock_irqsave(&ipath_devs_lock, flags);
 	}

 	spin_unlock_irqrestore(&ipath_devs_lock, flags);

 bail:
 	return ret;
 }

 static int ipathfs_get_sb(struct file_system_type *fs_type, int flags,
 			const char *dev_name, void *data, struct vfsmount *mnt)
 {
 	int ret = get_sb_single(fs_type, flags, data,
 				    ipathfs_fill_super, mnt);
 	if (ret >= 0)
 		ipath_super = mnt->mnt_sb;
 	return ret;
 }

 static void ipathfs_kill_super(struct super_block *s)
 {
 	kill_litter_super(s);
 	ipath_super = NULL;
 }

 int ipathfs_add_device(struct ipath_devdata *dd)
 {
 	int ret;

 	if (ipath_super == NULL) {
 		ret = 0;
 		goto bail;
 	}

 	ret = create_device_files(ipath_super, dd);

 bail:
 	return ret;
 }

 int ipathfs_remove_device(struct ipath_devdata *dd)
 {
 	int ret;

 	if (ipath_super == NULL) {
 		ret = 0;
 		goto bail;
 	}

 	ret = remove_device_files(ipath_super, dd);

 bail:
 	return ret;
 }

 static struct file_system_type ipathfs_fs_type = {
 	.owner =	THIS_MODULE,
 	.name =		"ipathfs",
 	.get_sb =	ipathfs_get_sb,
 	.kill_sb =	ipathfs_kill_super,
 };

 int __init ipath_init_ipathfs(void)
 {
 	return register_filesystem(&ipathfs_fs_type);
 }

 void __exit ipath_exit_ipathfs(void)
 {
 	unregister_filesystem(&ipathfs_fs_type);
 }
	/*
	* Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved.
	* Copyright (c) 2006 PathScale, Inc. All rights reserved.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* OpenIB.org BSD license below:
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above
	* copyright notice, this list of conditions and the following
	* disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials
	* provided with the distribution.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include <linux/module.h>
	#include <linux/fs.h>
	#include <linux/mount.h>
	#include <linux/pagemap.h>
	#include <linux/init.h>
	#include <linux/namei.h>
	#include <linux/slab.h>

	#include "ipath_kernel.h"

	#define IPATHFS_MAGIC 0x726a77

	static struct super_block *ipath_super;

	static int ipathfs_mknod(struct inode dir, struct dentry dentry,
	int mode, const struct file_operations *fops,
	void *data)
	{
	int error;
	struct inode *inode = new_inode(dir->i_sb);

	if (!inode) {
	error = -EPERM;
	goto bail;
	}

	inode->i_mode = mode;
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	inode->i_private = data;
	if ((mode & S_IFMT) == S_IFDIR) {
	inode->i_op = &simple_dir_inode_operations;
	inc_nlink(inode);
	inc_nlink(dir);
	}

	inode->i_fop = fops;

	d_instantiate(dentry, inode);
	error = 0;

	bail:
	return error;
	}

	static int create_file(const char *name, mode_t mode,
	struct dentry parent, struct dentry *dentry,
	const struct file_operations fops, void data)
	{
	int error;

	*dentry = NULL;
	mutex_lock(&parent->d_inode->i_mutex);
	*dentry = lookup_one_len(name, parent, strlen(name));
	if (!IS_ERR(*dentry))
	error = ipathfs_mknod(parent->d_inode, *dentry,
	mode, fops, data);
	else
	error = PTR_ERR(dentry);
	mutex_unlock(&parent->d_inode->i_mutex);

	return error;
	}

	static ssize_t atomic_stats_read(struct file file, char __user buf,
	size_t count, loff_t *ppos)
	{
	return simple_read_from_buffer(buf, count, ppos, &ipath_stats,
	sizeof ipath_stats);
	}

	static const struct file_operations atomic_stats_ops = {
	.read = atomic_stats_read,
	};

	static ssize_t atomic_counters_read(struct file file, char __user buf,
	size_t count, loff_t *ppos)
	{
	struct infinipath_counters counters;
	struct ipath_devdata *dd;

	dd = file->f_path.dentry->d_inode->i_private;
	dd->ipath_f_read_counters(dd, &counters);

	return simple_read_from_buffer(buf, count, ppos, &counters,
	sizeof counters);
	}

	static const struct file_operations atomic_counters_ops = {
	.read = atomic_counters_read,
	};

	static ssize_t flash_read(struct file file, char __user buf,
	size_t count, loff_t *ppos)
	{
	struct ipath_devdata *dd;
	ssize_t ret;
	loff_t pos;
	char *tmp;

	pos = *ppos;

	if ( pos < 0) {
	ret = -EINVAL;
	goto bail;
	}

	if (pos >= sizeof(struct ipath_flash)) {
	ret = 0;
	goto bail;
	}

	if (count > sizeof(struct ipath_flash) - pos)
	count = sizeof(struct ipath_flash) - pos;

	tmp = kmalloc(count, GFP_KERNEL);
	if (!tmp) {
	ret = -ENOMEM;
	goto bail;
	}

	dd = file->f_path.dentry->d_inode->i_private;
	if (ipath_eeprom_read(dd, pos, tmp, count)) {
	ipath_dev_err(dd, "failed to read from flash\n");
	ret = -ENXIO;
	goto bail_tmp;
	}

	if (copy_to_user(buf, tmp, count)) {
	ret = -EFAULT;
	goto bail_tmp;
	}

	*ppos = pos + count;
	ret = count;

	bail_tmp:
	kfree(tmp);

	bail:
	return ret;
	}

	static ssize_t flash_write(struct file file, const char __user buf,
	size_t count, loff_t *ppos)
	{
	struct ipath_devdata *dd;
	ssize_t ret;
	loff_t pos;
	char *tmp;

	pos = *ppos;

	if (pos != 0) {
	ret = -EINVAL;
	goto bail;
	}

	if (count != sizeof(struct ipath_flash)) {
	ret = -EINVAL;
	goto bail;
	}

	tmp = kmalloc(count, GFP_KERNEL);
	if (!tmp) {
	ret = -ENOMEM;
	goto bail;
	}

	if (copy_from_user(tmp, buf, count)) {
	ret = -EFAULT;
	goto bail_tmp;
	}

	dd = file->f_path.dentry->d_inode->i_private;
	if (ipath_eeprom_write(dd, pos, tmp, count)) {
	ret = -ENXIO;
	ipath_dev_err(dd, "failed to write to flash\n");
	goto bail_tmp;
	}

	*ppos = pos + count;
	ret = count;

	bail_tmp:
	kfree(tmp);

	bail:
	return ret;
	}

	static const struct file_operations flash_ops = {
	.read = flash_read,
	.write = flash_write,
	};

	static int create_device_files(struct super_block *sb,
	struct ipath_devdata *dd)
	{
	struct dentry dir, tmp;
	char unit[10];
	int ret;

	snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
	ret = create_file(unit, S_IFDIR\|S_IRUGO\|S_IXUGO, sb->s_root, &dir,
	&simple_dir_operations, dd);
	if (ret) {
	printk(KERN_ERR "create_file(%s) failed: %d\n", unit, ret);
	goto bail;
	}

	ret = create_file("atomic_counters", S_IFREG\|S_IRUGO, dir, &tmp,
	&atomic_counters_ops, dd);
	if (ret) {
	printk(KERN_ERR "create_file(%s/atomic_counters) "
	"failed: %d\n", unit, ret);
	goto bail;
	}

	ret = create_file("flash", S_IFREG\|S_IWUSR\|S_IRUGO, dir, &tmp,
	&flash_ops, dd);
	if (ret) {
	printk(KERN_ERR "create_file(%s/flash) "
	"failed: %d\n", unit, ret);
	goto bail;
	}

	bail:
	return ret;
	}

	static int remove_file(struct dentry parent, char name)
	{
	struct dentry *tmp;
	int ret;

	tmp = lookup_one_len(name, parent, strlen(name));

	if (IS_ERR(tmp)) {
	ret = PTR_ERR(tmp);
	goto bail;
	}

	spin_lock(&dcache_lock);
	spin_lock(&tmp->d_lock);
	if (!(d_unhashed(tmp) && tmp->d_inode)) {
	dget_locked(tmp);
	__d_drop(tmp);
	spin_unlock(&tmp->d_lock);
	spin_unlock(&dcache_lock);
	simple_unlink(parent->d_inode, tmp);
	} else {
	spin_unlock(&tmp->d_lock);
	spin_unlock(&dcache_lock);
	}

	ret = 0;
	bail:
	/*
	* We don't expect clients to care about the return value, but
	* it's there if they need it.
	*/
	return ret;
	}

	static int remove_device_files(struct super_block *sb,
	struct ipath_devdata *dd)
	{
	struct dentry dir, root;
	char unit[10];
	int ret;

	root = dget(sb->s_root);
	mutex_lock(&root->d_inode->i_mutex);
	snprintf(unit, sizeof unit, "%02d", dd->ipath_unit);
	dir = lookup_one_len(unit, root, strlen(unit));

	if (IS_ERR(dir)) {
	ret = PTR_ERR(dir);
	printk(KERN_ERR "Lookup of %s failed\n", unit);
	goto bail;
	}

	remove_file(dir, "flash");
	remove_file(dir, "atomic_counters");
	d_delete(dir);
	ret = simple_rmdir(root->d_inode, dir);

	bail:
	mutex_unlock(&root->d_inode->i_mutex);
	dput(root);
	return ret;
	}

	static int ipathfs_fill_super(struct super_block sb, void data,
	int silent)
	{
	struct ipath_devdata dd, tmp;
	unsigned long flags;
	int ret;

	static struct tree_descr files[] = {
	[2] = {"atomic_stats", &atomic_stats_ops, S_IRUGO},
	{""},
	};

	ret = simple_fill_super(sb, IPATHFS_MAGIC, files);
	if (ret) {
	printk(KERN_ERR "simple_fill_super failed: %d\n", ret);
	goto bail;
	}

	spin_lock_irqsave(&ipath_devs_lock, flags);

	list_for_each_entry_safe(dd, tmp, &ipath_dev_list, ipath_list) {
	spin_unlock_irqrestore(&ipath_devs_lock, flags);
	ret = create_device_files(sb, dd);
	if (ret)
	goto bail;
	spin_lock_irqsave(&ipath_devs_lock, flags);
	}

	spin_unlock_irqrestore(&ipath_devs_lock, flags);

	bail:
	return ret;
	}

	static int ipathfs_get_sb(struct file_system_type *fs_type, int flags,
	const char dev_name, void data, struct vfsmount *mnt)
	{
	int ret = get_sb_single(fs_type, flags, data,
	ipathfs_fill_super, mnt);
	if (ret >= 0)
	ipath_super = mnt->mnt_sb;
	return ret;
	}

	static void ipathfs_kill_super(struct super_block *s)
	{
	kill_litter_super(s);
	ipath_super = NULL;
	}

	int ipathfs_add_device(struct ipath_devdata *dd)
	{
	int ret;

	if (ipath_super == NULL) {
	ret = 0;
	goto bail;
	}

	ret = create_device_files(ipath_super, dd);

	bail:
	return ret;
	}

	int ipathfs_remove_device(struct ipath_devdata *dd)
	{
	int ret;

	if (ipath_super == NULL) {
	ret = 0;
	goto bail;
	}

	ret = remove_device_files(ipath_super, dd);

	bail:
	return ret;
	}

	static struct file_system_type ipathfs_fs_type = {
	.owner = THIS_MODULE,
	.name = "ipathfs",
	.get_sb = ipathfs_get_sb,
	.kill_sb = ipathfs_kill_super,
	};

	int __init ipath_init_ipathfs(void)
	{
	return register_filesystem(&ipathfs_fs_type);
	}

	void __exit ipath_exit_ipathfs(void)
	{
	unregister_filesystem(&ipathfs_fs_type);
	}