xtensa: keep sysmem banks ordered in mem_reserve

Rewrite mem_reserve so that it keeps bank order.
Also make its return code more traditional.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index df2b1d6..017c06a 100644 (file)
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -462,7 +462,7 @@ void __init setup_arch(char **cmdline_p)
 #ifdef CONFIG_BLK_DEV_INITRD
        if (initrd_start < initrd_end) {
                initrd_is_mapped = mem_reserve(__pa(initrd_start),
-                                              __pa(initrd_end), 0);
+                                              __pa(initrd_end), 0) == 0;
                initrd_below_start_ok = 1;
        } else {
                initrd_start = 0;

diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index 79c0c3d..5d23697 100644 (file)
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -142,6 +142,8 @@ int __init add_sysmem_bank(unsigned long start, unsigned long end)
  * mem_reserve(start, end, must_exist)
  *
  * Reserve some memory from the memory pool.
+ * If must_exist is set and a part of the region being reserved does not exist
+ * memory map is not altered.
  *
  * Parameters:
  *  start      Start of region,
@@ -149,53 +151,69 @@ int __init add_sysmem_bank(unsigned long start, unsigned long end)
  *  must_exist Must exist in memory pool.
  *
  * Returns:
- *  0 (memory area couldn't be mapped)
- * -1 (success)
+ *  0 (success)
+ *  < 0 (error)
  */
 
 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
 {
-       int i;
-
-       if (start == end)
-               return 0;
+       struct meminfo *it;
+       struct meminfo *rm = NULL;
+       unsigned long sz;
+       unsigned long bank_sz = 0;
 
        start = start & PAGE_MASK;
        end = PAGE_ALIGN(end);
+       sz = end - start;
+       if (!sz)
+               return -EINVAL;
 
-       for (i = 0; i < sysmem.nr_banks; i++)
-               if (start < sysmem.bank[i].end
-                   && end >= sysmem.bank[i].start)
-                       break;
+       it = find_bank(start);
+
+       if (it)
+               bank_sz = it->end - it->start;
 
-       if (i == sysmem.nr_banks) {
-               if (must_exist)
-                       printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
-                               "not in any region!\n", start, end);
-               return 0;
+       if ((!it || end - it->start > bank_sz) && must_exist) {
+               pr_warn("mem_reserve: [0x%0lx, 0x%0lx) not in any region!\n",
+                       start, end);
+               return -EINVAL;
        }
 
-       if (start > sysmem.bank[i].start) {
-               if (end < sysmem.bank[i].end) {
-                       /* split entry */
-                       if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
-                               panic("meminfo overflow\n");
-                       sysmem.bank[sysmem.nr_banks].start = end;
-                       sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
-                       sysmem.nr_banks++;
+       if (it && start - it->start < bank_sz) {
+               if (start == it->start) {
+                       if (end - it->start < bank_sz) {
+                               it->start = end;
+                               return 0;
+                       } else {
+                               rm = it;
+                       }
+               } else {
+                       it->end = start;
+                       if (end - it->start < bank_sz)
+                               return add_sysmem_bank(end,
+                                                      it->start + bank_sz);
+                       ++it;
                }
-               sysmem.bank[i].end = start;
+       }
 
-       } else if (end < sysmem.bank[i].end) {
-               sysmem.bank[i].start = end;
+       if (!it)
+               it = sysmem.bank;
 
-       } else {
-               /* remove entry */
-               sysmem.nr_banks--;
-               sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
-               sysmem.bank[i].end   = sysmem.bank[sysmem.nr_banks].end;
+       for (; it < sysmem.bank + sysmem.nr_banks; ++it) {
+               if (it->end - start <= sz) {
+                       if (!rm)
+                               rm = it;
+               } else {
+                       if (it->start - start < sz)
+                               it->start = end;
+                       break;
+               }
        }
-       return -1;
+
+       if (rm)
+               move_banks(rm, it);
+
+       return 0;
 }