1 files changed, 28 insertions, 53 deletions

diff --git a/drivers/iommu/omap-iommu-debug.c b/drivers/iommu/omap-iommu-debug.c
index 41b09a1d78ea..f3d20a2039d2 100644
--- a/drivers/iommu/omap-iommu-debug.c
+++ b/drivers/iommu/omap-iommu-debug.c
@@ -85,95 +85,70 @@ static ssize_t debug_read_tlb(struct file *file, char __user *userbuf,
 	return bytes;
 }
 
-#define dump_ioptable_entry_one(lv, da, val)			\
-	({							\
-		int __err = 0;					\
-		ssize_t bytes;					\
-		const int maxcol = 22;				\
-		const char *str = "%d: %08x %08x\n";		\
-		bytes = snprintf(p, maxcol, str, lv, da, val);	\
-		p += bytes;					\
-		len -= bytes;					\
-		if (len < maxcol)				\
-			__err = -ENOMEM;			\
-		__err;						\
-	})
-
-static ssize_t dump_ioptable(struct omap_iommu *obj, char *buf, ssize_t len)
+static void dump_ioptable(struct seq_file *s)
 {
-	int i;
-	u32 *iopgd;
-	char *p = buf;
+	int i, j;
+	u32 da;
+	u32 *iopgd, *iopte;
+	struct omap_iommu *obj = s->private;
 
 	spin_lock(&obj->page_table_lock);
 
 	iopgd = iopgd_offset(obj, 0);
 	for (i = 0; i < PTRS_PER_IOPGD; i++, iopgd++) {
-		int j, err;
-		u32 *iopte;
-		u32 da;
-
 		if (!*iopgd)
 			continue;
 
 		if (!(*iopgd & IOPGD_TABLE)) {
 			da = i << IOPGD_SHIFT;
-
-			err = dump_ioptable_entry_one(1, da, *iopgd);
-			if (err)
-				goto out;
+			seq_printf(s, "1: 0x%08x 0x%08x\n", da, *iopgd);
 			continue;
 		}
 
 		iopte = iopte_offset(iopgd, 0);
-
 		for (j = 0; j < PTRS_PER_IOPTE; j++, iopte++) {
 			if (!*iopte)
 				continue;
 
 			da = (i << IOPGD_SHIFT) + (j << IOPTE_SHIFT);
-			err = dump_ioptable_entry_one(2, da, *iopgd);
-			if (err)
-				goto out;
+			seq_printf(s, "2: 0x%08x 0x%08x\n", da, *iopte);
 		}
 	}
-out:
-	spin_unlock(&obj->page_table_lock);
 
-	return p - buf;
+	spin_unlock(&obj->page_table_lock);
 }
 
-static ssize_t debug_read_pagetable(struct file *file, char __user *userbuf,
-				    size_t count, loff_t *ppos)
+static int debug_read_pagetable(struct seq_file *s, void *data)
 {
-	struct omap_iommu *obj = file->private_data;
-	char *p, *buf;
-	size_t bytes;
+	struct omap_iommu *obj = s->private;
 
 	if (is_omap_iommu_detached(obj))
 		return -EPERM;
 
-	buf = (char *)__get_free_page(GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-	p = buf;
-
-	p += sprintf(p, "L: %8s %8s\n", "da:", "pa:");
-	p += sprintf(p, "-----------------------------------------\n");
-
 	mutex_lock(&iommu_debug_lock);
 
-	bytes = PAGE_SIZE - (p - buf);
-	p += dump_ioptable(obj, p, bytes);
-
-	bytes = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+	seq_printf(s, "L: %8s %8s\n", "da:", "pte:");
+	seq_puts(s, "--------------------------\n");
+	dump_ioptable(s);
 
 	mutex_unlock(&iommu_debug_lock);
-	free_page((unsigned long)buf);
 
-	return bytes;
+	return 0;
 }
 
+#define DEBUG_SEQ_FOPS_RO(name)						       \
+	static int debug_open_##name(struct inode *inode, struct file *file)   \
+	{								       \
+		return single_open(file, debug_read_##name, inode->i_private); \
+	}								       \
+									       \
+	static const struct file_operations debug_##name##_fops = {	       \
+		.open		= debug_open_##name,			       \
+		.read		= seq_read,				       \
+		.llseek		= seq_lseek,				       \
+		.release	= single_release,			       \
+	}
+
 #define DEBUG_FOPS_RO(name)						\
 	static const struct file_operations debug_##name##_fops = {	\
 		.open = simple_open,					\
@@ -183,7 +158,7 @@ static ssize_t debug_read_pagetable(struct file *file, char __user *userbuf,
 
 DEBUG_FOPS_RO(regs);
 DEBUG_FOPS_RO(tlb);
-DEBUG_FOPS_RO(pagetable);
+DEBUG_SEQ_FOPS_RO(pagetable);
 
 #define __DEBUG_ADD_FILE(attr, mode)					\
 	{								\