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>
diff --git a/drivers/iommu/omap-iommu-debug.c b/drivers/iommu/omap-iommu-debug.c
index a520438..28de657 100644
--- a/drivers/iommu/omap-iommu-debug.c
+++ b/drivers/iommu/omap-iommu-debug.c
@@ -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 @@
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 @@
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 @@
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 @@
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 @@
DEBUG_ADD_FILE_RO(regs);
DEBUG_ADD_FILE_RO(tlb);
- DEBUG_ADD_FILE(pagetable);
+ DEBUG_ADD_FILE_RO(pagetable);
return 0;