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Commit 3ca5db07 authored by Suman Anna's avatar Suman Anna Committed by Joerg Roedel
Browse files

iommu/omap: Make pagetable debugfs entry read-only 



Remove the writeability on the 'pagetable' debugfs entry,
so that the mapping/unmapping into an OMAP IOMMU is only
limited to actual client devices/drivers at kernel-level.

Signed-off-by: default avatarSuman Anna <s-anna@ti.com>
Acked-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 68570a74

drivers/iommu/omap-iommu-debug.c

+2 −46
Original line number Diff line number Diff line
@@ -24,8 +24,6 @@ 
#include "omap-iopgtable.h"

#include "omap-iommu.h"



#define MAXCOLUMN 100 /* for short messages */



static DEFINE_MUTEX(iommu_debug_lock);



static struct dentry *iommu_debug_root;
@@ -82,39 +80,6 @@ static ssize_t debug_read_tlb(struct file *file, char __user *userbuf, 
	return bytes;

}



static ssize_t debug_write_pagetable(struct file *file,

		     const char __user *userbuf, size_t count, loff_t *ppos)

{

	struct iotlb_entry e;

	struct cr_regs cr;

	int err;

	struct device *dev = file->private_data;

	struct omap_iommu *obj = dev_to_omap_iommu(dev);

	char buf[MAXCOLUMN], *p = buf;



	count = min(count, sizeof(buf));



	mutex_lock(&iommu_debug_lock);

	if (copy_from_user(p, userbuf, count)) {

		mutex_unlock(&iommu_debug_lock);

		return -EFAULT;

	}



	sscanf(p, "%x %x", &cr.cam, &cr.ram);

	if (!cr.cam || !cr.ram) {

		mutex_unlock(&iommu_debug_lock);

		return -EINVAL;

	}



	omap_iotlb_cr_to_e(&cr, &e);

	err = omap_iopgtable_store_entry(obj, &e);

	if (err)

		dev_err(obj->dev, "%s: fail to store cr\n", __func__);



	mutex_unlock(&iommu_debug_lock);

	return count;

}



#define dump_ioptable_entry_one(lv, da, val)			\

	({							\

		int __err = 0;					\
@@ -202,14 +167,6 @@ static ssize_t debug_read_pagetable(struct file *file, char __user *userbuf, 
	return bytes;

}



#define DEBUG_FOPS(name)						\

	static const struct file_operations debug_##name##_fops = {	\

		.open = simple_open,					\

		.read = debug_read_##name,				\

		.write = debug_write_##name,				\

		.llseek = generic_file_llseek,				\

	};



#define DEBUG_FOPS_RO(name)						\

	static const struct file_operations debug_##name##_fops = {	\

		.open = simple_open,					\
@@ -219,7 +176,7 @@ static ssize_t debug_read_pagetable(struct file *file, char __user *userbuf, 


DEBUG_FOPS_RO(regs);

DEBUG_FOPS_RO(tlb);

DEBUG_FOPS(pagetable);

DEBUG_FOPS_RO(pagetable);



#define __DEBUG_ADD_FILE(attr, mode)					\

	{								\
@@ -230,7 +187,6 @@ DEBUG_FOPS(pagetable); 
			return -ENOMEM;					\

	}



#define DEBUG_ADD_FILE(name) __DEBUG_ADD_FILE(name, 0600)

#define DEBUG_ADD_FILE_RO(name) __DEBUG_ADD_FILE(name, 0400)



static int iommu_debug_register(struct device *dev, void *data)
@@ -263,7 +219,7 @@ static int iommu_debug_register(struct device *dev, void *data) 


	DEBUG_ADD_FILE_RO(regs);

	DEBUG_ADD_FILE_RO(tlb);

	DEBUG_ADD_FILE(pagetable);

	DEBUG_ADD_FILE_RO(pagetable);



	return 0;