It will try find area according with size/align in specified range (start, end).
lmb_find_area() will honor goal/limit.
also make it more easy for x86 to use lmb.
x86 early_res is using find/reserve pattern instead of alloc.
When we need temporaray buff for range array etc for range work, if We are using
lmb_alloc(), We will need to add some post fix code for buffer that is used
by range array, because it is in the lmb.reserved already. and have to call
extra lmb_free().
-v2: Change name to lmb_find_area() according to Michael Ellerman
-v3: Add generic weak version __lmb_find_area()
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
include/linux/lmb.h | 4 ++++
mm/lmb.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 53 insertions(+), 0 deletions(-)
diff --git a/include/linux/lmb.h b/include/linux/lmb.h
index e14ea8d..4cf2f3b 100644
--- a/include/linux/lmb.h
+++ b/include/linux/lmb.h
@@ -83,6 +83,10 @@ lmb_end_pfn(struct lmb_region *type, unsigned long region_nr)
lmb_size_pages(type, region_nr);
}
+u64 __lmb_find_area(u64 ei_start, u64 ei_last, u64 start, u64 end,
+ u64 size, u64 align);
+u64 lmb_find_area(u64 start, u64 end, u64 size, u64 align);
+
#include <asm/lmb.h>
#endif /* __KERNEL__ */
diff --git a/mm/lmb.c b/mm/lmb.c
index 392d805..6739e4f 100644
--- a/mm/lmb.c
+++ b/mm/lmb.c
@@ -11,9 +11,13 @@
*/
#include <linux/kernel.h>
+#include <linux/types.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/lmb.h>
+#include <linux/bootmem.h>
+#include <linux/mm.h>
+#include <linux/range.h>
#define LMB_ALLOC_ANYWHERE 0
@@ -559,3 +563,48 @@ int lmb_find(struct lmb_property *res)
}
return -1;
}
+
+u64 __init __weak __lmb_find_area(u64 ei_start, u64 ei_last, u64 start, u64 end,
+ u64 size, u64 align)
+{
+ u64 final_start, final_end;
+ u64 mem;
+
+ final_start = max(ei_start, start);
+ final_end = min(ei_last, end);
+
+ if (final_start >= final_end)
+ return -1ULL;
+
+ mem = __lmb_find_base(size, align, final_end);
+
+ if (mem == -1ULL)
+ return -1ULL;
+
+ lmb_free(mem, size);
+ if (mem >= final_start)
+ return mem;
+
+ return -1ULL;
+}
+
+/*
+ * Find a free area with specified alignment in a specific range.
+ */
+u64 __init lmb_find_area(u64 start, u64 end, u64 size, u64 align)
+{
+ int i;
+
+ for (i = 0; i < lmb.memory.cnt; i++) {
+ u64 ei_start = lmb.memory.region[i].base;
+ u64 ei_last = ei_start + lmb.memory.region[i].size;
+ u64 addr;
+
+ addr = __lmb_find_area(ei_start, ei_last, start, end,
+ size, align);
+
+ if (addr != -1ULL)
+ return addr;
+ }
+ return -1ULL;
+}
--
1.6.4.2
--
