1 files changed, 87 insertions, 59 deletions

diff --git a/lib/lmb.c b/lib/lmb.c
index 93fc1bea07c..bb6f232f6bc 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -23,6 +23,9 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+#define LMB_RGN_OVERLAP		1
+#define LMB_RGN_ADJACENT	2
+
 /*
  * The following low level LMB functions must not access the global LMB memory
  * map since they are also used to manage IOVA memory maps in iommu drivers like
@@ -49,8 +52,22 @@ static long lmb_addrs_adjacent(phys_addr_t base1, phys_size_t size1,
 	return 0;
 }
 
-static long lmb_regions_overlap(struct alist *lmb_rgn_lst, unsigned long r1,
-				unsigned long r2)
+/**
+ * lmb_regions_check() - Check if the regions overlap, or are adjacent
+ * @lmb_rgn_lst: List of LMB regions
+ * @r1: First region to check
+ * @r2: Second region to check
+ *
+ * Check if the two regions with matching flags, r1 and r2 are
+ * adjacent to each other, or if they overlap.
+ *
+ * Return:
+ * * %LMB_RGN_OVERLAP	- Regions overlap
+ * * %LMB_RGN_ADJACENT	- Regions adjacent to each other
+ * * 0			- Neither of the above, or flags mismatch
+ */
+static long lmb_regions_check(struct alist *lmb_rgn_lst, unsigned long r1,
+			      unsigned long r2)
 {
 	struct lmb_region *rgn = lmb_rgn_lst->data;
 	phys_addr_t base1 = rgn[r1].base;
@@ -58,19 +75,15 @@ static long lmb_regions_overlap(struct alist *lmb_rgn_lst, unsigned long r1,
 	phys_addr_t base2 = rgn[r2].base;
 	phys_size_t size2 = rgn[r2].size;
 
-	return lmb_addrs_overlap(base1, size1, base2, size2);
-}
+	if (rgn[r1].flags != rgn[r2].flags)
+		return 0;
 
-static long lmb_regions_adjacent(struct alist *lmb_rgn_lst, unsigned long r1,
-				 unsigned long r2)
-{
-	struct lmb_region *rgn = lmb_rgn_lst->data;
-	phys_addr_t base1 = rgn[r1].base;
-	phys_size_t size1 = rgn[r1].size;
-	phys_addr_t base2 = rgn[r2].base;
-	phys_size_t size2 = rgn[r2].size;
+	if (lmb_addrs_overlap(base1, size1, base2, size2))
+		return LMB_RGN_OVERLAP;
+	else if (lmb_addrs_adjacent(base1, size1, base2, size2))
+		return LMB_RGN_ADJACENT;
 
-	return lmb_addrs_adjacent(base1, size1, base2, size2);
+	return 0;
 }
 
 static void lmb_remove_region(struct alist *lmb_rgn_lst, unsigned long r)
@@ -96,25 +109,6 @@ static void lmb_coalesce_regions(struct alist *lmb_rgn_lst, unsigned long r1,
 	lmb_remove_region(lmb_rgn_lst, r2);
 }
 
-/*Assumption : base addr of region 1 < base addr of region 2*/
-static void lmb_fix_over_lap_regions(struct alist *lmb_rgn_lst,
-				     unsigned long r1, unsigned long r2)
-{
-	struct lmb_region *rgn = lmb_rgn_lst->data;
-
-	phys_addr_t base1 = rgn[r1].base;
-	phys_size_t size1 = rgn[r1].size;
-	phys_addr_t base2 = rgn[r2].base;
-	phys_size_t size2 = rgn[r2].size;
-
-	if (base1 + size1 > base2 + size2) {
-		printf("This will not be a case any time\n");
-		return;
-	}
-	rgn[r1].size = base2 + size2 - base1;
-	lmb_remove_region(lmb_rgn_lst, r2);
-}
-
 static long lmb_resize_regions(struct alist *lmb_rgn_lst,
 			       unsigned long idx_start,
 			       phys_addr_t base, phys_size_t size)
@@ -209,14 +203,11 @@ static long lmb_add_region_flags(struct alist *lmb_rgn_lst, phys_addr_t base,
 			break;
 		} else if (ret < 0) {
 			if (flags != rgnflags)
-				break;
+				continue;
 			rgn[i].size += size;
 			coalesced++;
 			break;
 		} else if (lmb_addrs_overlap(base, size, rgnbase, rgnsize)) {
-			if (flags != LMB_NONE)
-				return -EEXIST;
-
 			ret = lmb_resize_regions(lmb_rgn_lst, i, base, size);
 			if (ret < 0)
 				return -1;
@@ -229,16 +220,21 @@ static long lmb_add_region_flags(struct alist *lmb_rgn_lst, phys_addr_t base,
 	}
 
 	if (lmb_rgn_lst->count && i < lmb_rgn_lst->count - 1) {
-		rgn = lmb_rgn_lst->data;
-		if (rgn[i].flags == rgn[i + 1].flags) {
-			if (lmb_regions_adjacent(lmb_rgn_lst, i, i + 1)) {
-				lmb_coalesce_regions(lmb_rgn_lst, i, i + 1);
-				coalesced++;
-			} else if (lmb_regions_overlap(lmb_rgn_lst, i, i + 1)) {
-				/* fix overlapping area */
-				lmb_fix_over_lap_regions(lmb_rgn_lst, i, i + 1);
-				coalesced++;
-			}
+		ret = lmb_regions_check(lmb_rgn_lst, i, i + 1);
+		if (ret == LMB_RGN_ADJACENT) {
+			lmb_coalesce_regions(lmb_rgn_lst, i, i + 1);
+			coalesced++;
+		} else if (ret == LMB_RGN_OVERLAP) {
+			/* fix overlapping areas */
+			phys_addr_t rgnbase = rgn[i].base;
+			phys_size_t rgnsize = rgn[i].size;
+
+			ret = lmb_resize_regions(lmb_rgn_lst, i,
+						 rgnbase, rgnsize);
+			if (ret < 0)
+				return -1;
+
+			coalesced++;
 		}
 	}
 
@@ -561,6 +557,39 @@ static __maybe_unused void lmb_reserve_common_spl(void)
 	}
 }
 
+/**
+ * lmb_can_reserve_region() - check if the region can be reserved
+ * @base: base address of region to be reserved
+ * @size: size of region to be reserved
+ * @flags: flag of the region to be reserved
+ *
+ * Go through all the reserved regions and ensure that the requested
+ * region does not overlap with any existing regions. An overlap is
+ * allowed only when the flag of the request region and the existing
+ * region is LMB_NONE.
+ *
+ * Return: true if region can be reserved, false otherwise
+ */
+static bool lmb_can_reserve_region(phys_addr_t base, phys_size_t size,
+				   u32 flags)
+{
+	uint i;
+	struct lmb_region *lmb_reserved = lmb.used_mem.data;
+
+	for (i = 0; i < lmb.used_mem.count; i++) {
+		u32 rgnflags = lmb_reserved[i].flags;
+		phys_addr_t rgnbase = lmb_reserved[i].base;
+		phys_size_t rgnsize = lmb_reserved[i].size;
+
+		if (lmb_addrs_overlap(base, size, rgnbase, rgnsize)) {
+			if (flags != LMB_NONE || flags != rgnflags)
+				return false;
+		}
+	}
+
+	return true;
+}
+
 void lmb_add_memory(void)
 {
 	int i;
@@ -633,6 +662,9 @@ long lmb_reserve(phys_addr_t base, phys_size_t size, u32 flags)
 	long ret = 0;
 	struct alist *lmb_rgn_lst = &lmb.used_mem;
 
+	if (!lmb_can_reserve_region(base, size, flags))
+		return -EEXIST;
+
 	ret = lmb_add_region_flags(lmb_rgn_lst, base, size, flags);
 	if (ret)
 		return ret;
@@ -692,29 +724,25 @@ static phys_addr_t _lmb_alloc_base(phys_size_t size, ulong align,
 			base = ALIGN_DOWN(res_base - size, align);
 		}
 	}
+
+	log_debug("%s: Failed to allocate 0x%lx bytes below 0x%lx\n",
+		  __func__, (ulong)size, (ulong)max_addr);
+
 	return 0;
 }
 
 phys_addr_t lmb_alloc(phys_size_t size, ulong align)
 {
-	return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE, LMB_NONE);
+	return _lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE, LMB_NONE);
 }
 
 phys_addr_t lmb_alloc_base(phys_size_t size, ulong align, phys_addr_t max_addr,
 			   uint flags)
 {
-	phys_addr_t alloc;
-
-	alloc = _lmb_alloc_base(size, align, max_addr, flags);
-
-	if (alloc == 0)
-		printf("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n",
-		       (ulong)size, (ulong)max_addr);
-
-	return alloc;
+	return _lmb_alloc_base(size, align, max_addr, flags);
 }
 
-phys_addr_t lmb_alloc_addr(phys_addr_t base, phys_size_t size, u32 flags)
+int lmb_alloc_addr(phys_addr_t base, phys_size_t size, u32 flags)
 {
 	long rgn;
 	struct lmb_region *lmb_memory = lmb.available_mem.data;
@@ -731,11 +759,11 @@ phys_addr_t lmb_alloc_addr(phys_addr_t base, phys_size_t size, u32 flags)
 				      base + size - 1, 1)) {
 			/* ok, reserve the memory */
 			if (!lmb_reserve(base, size, flags))
-				return base;
+				return 0;
 		}
 	}
 
-	return 0;
+	return -1;
 }
 
 /* Return number of bytes from a given address that are free */