powerpc/mm: Increase the slice range to 64TB

This patch makes the high psizes mask as an unsigned char array
so that we can have more than 16TB. Currently we support upto
64TB

Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 68 insertions, 39 deletions

diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 73709f7ce92..b4e996a398b 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -42,7 +42,7 @@ int _slice_debug = 1;
 
 static void slice_print_mask(const char *label, struct slice_mask mask)
 {
-	char	*p, buf[16 + 3 + 16 + 1];
+	char	*p, buf[16 + 3 + 64 + 1];
 	int	i;
 
 	if (!_slice_debug)
@@ -54,7 +54,7 @@ static void slice_print_mask(const char *label, struct slice_mask mask)
 	*(p++) = '-';
 	*(p++) = ' ';
 	for (i = 0; i < SLICE_NUM_HIGH; i++)
-		*(p++) = (mask.high_slices & (1 << i)) ? '1' : '0';
+		*(p++) = (mask.high_slices & (1ul << i)) ? '1' : '0';
 	*(p++) = 0;
 
 	printk(KERN_DEBUG "%s:%s\n", label, buf);
@@ -84,8 +84,8 @@ static struct slice_mask slice_range_to_mask(unsigned long start,
 	}
 
 	if ((start + len) > SLICE_LOW_TOP)
-		ret.high_slices = (1u << (GET_HIGH_SLICE_INDEX(end) + 1))
-			- (1u << GET_HIGH_SLICE_INDEX(start));
+		ret.high_slices = (1ul << (GET_HIGH_SLICE_INDEX(end) + 1))
+			- (1ul << GET_HIGH_SLICE_INDEX(start));
 
 	return ret;
 }
@@ -135,26 +135,31 @@ static struct slice_mask slice_mask_for_free(struct mm_struct *mm)
 
 	for (i = 0; i < SLICE_NUM_HIGH; i++)
 		if (!slice_high_has_vma(mm, i))
-			ret.high_slices |= 1u << i;
+			ret.high_slices |= 1ul << i;
 
 	return ret;
 }
 
 static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize)
 {
+	unsigned char *hpsizes;
+	int index, mask_index;
 	struct slice_mask ret = { 0, 0 };
 	unsigned long i;
-	u64 psizes;
+	u64 lpsizes;
 
-	psizes = mm->context.low_slices_psize;
+	lpsizes = mm->context.low_slices_psize;
 	for (i = 0; i < SLICE_NUM_LOW; i++)
-		if (((psizes >> (i * 4)) & 0xf) == psize)
+		if (((lpsizes >> (i * 4)) & 0xf) == psize)
 			ret.low_slices |= 1u << i;
 
-	psizes = mm->context.high_slices_psize;
-	for (i = 0; i < SLICE_NUM_HIGH; i++)
-		if (((psizes >> (i * 4)) & 0xf) == psize)
-			ret.high_slices |= 1u << i;
+	hpsizes = mm->context.high_slices_psize;
+	for (i = 0; i < SLICE_NUM_HIGH; i++) {
+		mask_index = i & 0x1;
+		index = i >> 1;
+		if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
+			ret.high_slices |= 1ul << i;
+	}
 
 	return ret;
 }
@@ -183,8 +188,10 @@ static void slice_flush_segments(void *parm)
 
 static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
 {
+	int index, mask_index;
 	/* Write the new slice psize bits */
-	u64 lpsizes, hpsizes;
+	unsigned char *hpsizes;
+	u64 lpsizes;
 	unsigned long i, flags;
 
 	slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
@@ -201,14 +208,18 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
 			lpsizes = (lpsizes & ~(0xful << (i * 4))) |
 				(((unsigned long)psize) << (i * 4));
 
-	hpsizes = mm->context.high_slices_psize;
-	for (i = 0; i < SLICE_NUM_HIGH; i++)
-		if (mask.high_slices & (1u << i))
-			hpsizes = (hpsizes & ~(0xful << (i * 4))) |
-				(((unsigned long)psize) << (i * 4));
-
+	/* Assign the value back */
 	mm->context.low_slices_psize = lpsizes;
-	mm->context.high_slices_psize = hpsizes;
+
+	hpsizes = mm->context.high_slices_psize;
+	for (i = 0; i < SLICE_NUM_HIGH; i++) {
+		mask_index = i & 0x1;
+		index = i >> 1;
+		if (mask.high_slices & (1ul << i))
+			hpsizes[index] = (hpsizes[index] &
+					  ~(0xf << (mask_index * 4))) |
+				(((unsigned long)psize) << (mask_index * 4));
+	}
 
 	slice_dbg(" lsps=%lx, hsps=%lx\n",
 		  mm->context.low_slices_psize,
@@ -587,18 +598,19 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
 
 unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
 {
-	u64 psizes;
-	int index;
+	unsigned char *hpsizes;
+	int index, mask_index;
 
 	if (addr < SLICE_LOW_TOP) {
-		psizes = mm->context.low_slices_psize;
+		u64 lpsizes;
+		lpsizes = mm->context.low_slices_psize;
 		index = GET_LOW_SLICE_INDEX(addr);
-	} else {
-		psizes = mm->context.high_slices_psize;
-		index = GET_HIGH_SLICE_INDEX(addr);
+		return (lpsizes >> (index * 4)) & 0xf;
 	}
-
-	return (psizes >> (index * 4)) & 0xf;
+	hpsizes = mm->context.high_slices_psize;
+	index = GET_HIGH_SLICE_INDEX(addr);
+	mask_index = index & 0x1;
+	return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xf;
 }
 EXPORT_SYMBOL_GPL(get_slice_psize);
 
@@ -618,7 +630,9 @@ EXPORT_SYMBOL_GPL(get_slice_psize);
  */
 void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
 {
-	unsigned long flags, lpsizes, hpsizes;
+	int index, mask_index;
+	unsigned char *hpsizes;
+	unsigned long flags, lpsizes;
 	unsigned int old_psize;
 	int i;
 
@@ -639,15 +653,21 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
 		if (((lpsizes >> (i * 4)) & 0xf) == old_psize)
 			lpsizes = (lpsizes & ~(0xful << (i * 4))) |
 				(((unsigned long)psize) << (i * 4));
+	/* Assign the value back */
+	mm->context.low_slices_psize = lpsizes;
 
 	hpsizes = mm->context.high_slices_psize;
-	for (i = 0; i < SLICE_NUM_HIGH; i++)
-		if (((hpsizes >> (i * 4)) & 0xf) == old_psize)
-			hpsizes = (hpsizes & ~(0xful << (i * 4))) |
-				(((unsigned long)psize) << (i * 4));
+	for (i = 0; i < SLICE_NUM_HIGH; i++) {
+		mask_index = i & 0x1;
+		index = i >> 1;
+		if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize)
+			hpsizes[index] = (hpsizes[index] &
+					  ~(0xf << (mask_index * 4))) |
+				(((unsigned long)psize) << (mask_index * 4));
+	}
+
+
 
-	mm->context.low_slices_psize = lpsizes;
-	mm->context.high_slices_psize = hpsizes;
 
 	slice_dbg(" lsps=%lx, hsps=%lx\n",
 		  mm->context.low_slices_psize,
@@ -660,18 +680,27 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
 void slice_set_psize(struct mm_struct *mm, unsigned long address,
 		     unsigned int psize)
 {
+	unsigned char *hpsizes;
 	unsigned long i, flags;
-	u64 *p;
+	u64 *lpsizes;
 
 	spin_lock_irqsave(&slice_convert_lock, flags);
 	if (address < SLICE_LOW_TOP) {
 		i = GET_LOW_SLICE_INDEX(address);
-		p = &mm->context.low_slices_psize;
+		lpsizes = &mm->context.low_slices_psize;
+		*lpsizes = (*lpsizes & ~(0xful << (i * 4))) |
+			((unsigned long) psize << (i * 4));
 	} else {
+		int index, mask_index;
 		i = GET_HIGH_SLICE_INDEX(address);
-		p = &mm->context.high_slices_psize;
+		hpsizes = mm->context.high_slices_psize;
+		mask_index = i & 0x1;
+		index = i >> 1;
+		hpsizes[index] = (hpsizes[index] &
+				  ~(0xf << (mask_index * 4))) |
+			(((unsigned long)psize) << (mask_index * 4));
 	}
-	*p = (*p & ~(0xful << (i * 4))) | ((unsigned long) psize << (i * 4));
+
 	spin_unlock_irqrestore(&slice_convert_lock, flags);
 
 #ifdef CONFIG_SPU_BASE