Merge tag 'trace-3.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...

[deliverable/linux.git] / mm / cma.c

diff --git a/mm/cma.c b/mm/cma.c
index c17751c0dcafb95eda9f41e9cdc9ce101edbebed..474c644a0dc6deafea451935e6d44b72d5e1903e 100644 (file)
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -32,6 +32,7 @@
 #include <linux/slab.h>
 #include <linux/log2.h>
 #include <linux/cma.h>
+#include <linux/highmem.h>
 
 struct cma {
        unsigned long   base_pfn;
@@ -163,6 +164,8 @@ int __init cma_declare_contiguous(phys_addr_t base,
                        bool fixed, struct cma **res_cma)
 {
        struct cma *cma;
+       phys_addr_t memblock_end = memblock_end_of_DRAM();
+       phys_addr_t highmem_start = __pa(high_memory);
        int ret = 0;
 
        pr_debug("%s(size %lx, base %08lx, limit %08lx alignment %08lx)\n",
@@ -196,6 +199,24 @@ int __init cma_declare_contiguous(phys_addr_t base,
        if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit))
                return -EINVAL;
 
+       /*
+        * adjust limit to avoid crossing low/high memory boundary for
+        * automatically allocated regions
+        */
+       if (((limit == 0 || limit > memblock_end) &&
+            (memblock_end - size < highmem_start &&
+             memblock_end > highmem_start)) ||
+           (!fixed && limit > highmem_start && limit - size < highmem_start)) {
+               limit = highmem_start;
+       }
+
+       if (fixed && base < highmem_start && base+size > highmem_start) {
+               ret = -EINVAL;
+               pr_err("Region at %08lx defined on low/high memory boundary (%08lx)\n",
+                       (unsigned long)base, (unsigned long)highmem_start);
+               goto err;
+       }
+
        /* Reserve memory */
        if (base && fixed) {
                if (memblock_is_region_reserved(base, size) ||