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: Suman Anna <s-anna@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Suman Anna 2014-10-22 17:22:29 -05:00 committed by Joerg Roedel
parent 68570a7446
commit 3ca5db072c

View file

@ -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;