memblock, x86: Reimplement memblock_find_dma_reserve() using iterators

memblock_find_dma_reserve() wants to find out how much memory is
reserved under MAX_DMA_PFN.  memblock_x86_memory_[free_]in_range() are
used to find out the amounts of all available and free memory in the
area, which are then subtracted to find out the amount of reservation.

memblock_x86_memblock_[free_]in_range() are implemented using
__memblock_x86_memory_in_range() which builds ranges from memblock and
then count them, which is rather unnecessarily complex.

This patch open codes the counting logic directly in
memblock_find_dma_reserve() using memblock iterators and removes now
unused __memblock_x86_memory_in_range() and find_range_array().

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-11-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/arch/x86/include/asm/memblock.h b/arch/x86/include/asm/memblock.h
index bc9e44b0812d431f3dd01a3c14c25b1dc0aa9edc..a0cc7d66ac55bc257f1c4fa17c066a2ea2fc5d0d 100644 (file)
--- a/arch/x86/include/asm/memblock.h
+++ b/arch/x86/include/asm/memblock.h
@@ -7,7 +7,5 @@ void memblock_x86_reserve_range(u64 start, u64 end, char *name);
 void memblock_x86_free_range(u64 start, u64 end);
 
 u64 memblock_x86_hole_size(u64 start, u64 end);
-u64 memblock_x86_free_memory_in_range(u64 addr, u64 limit);
-u64 memblock_x86_memory_in_range(u64 addr, u64 limit);
 
 #endif

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index b99d9402ae8bc80d7aa520a881415e21137ffb4a..84475f1e220127bcb3ae1414634ed4395c815496 100644 (file)
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1093,15 +1093,30 @@ void __init memblock_x86_fill(void)
 void __init memblock_find_dma_reserve(void)
 {
 #ifdef CONFIG_X86_64
-       u64 free_size_pfn;
-       u64 mem_size_pfn;
+       u64 nr_pages = 0, nr_free_pages = 0;
+       unsigned long start_pfn, end_pfn;
+       phys_addr_t start, end;
+       int i;
+       u64 u;
+
        /*
         * need to find out used area below MAX_DMA_PFN
         * need to use memblock to get free size in [0, MAX_DMA_PFN]
         * at first, and assume boot_mem will not take below MAX_DMA_PFN
         */
-       mem_size_pfn = memblock_x86_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
-       free_size_pfn = memblock_x86_free_memory_in_range(0, MAX_DMA_PFN << PAGE_SHIFT) >> PAGE_SHIFT;
-       set_dma_reserve(mem_size_pfn - free_size_pfn);
+       for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
+               start_pfn = min_t(unsigned long, start_pfn, MAX_DMA_PFN);
+               end_pfn = min_t(unsigned long, end_pfn, MAX_DMA_PFN);
+               nr_pages += end_pfn - start_pfn;
+       }
+
+       for_each_free_mem_range(u, MAX_NUMNODES, &start, &end, NULL) {
+               start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
+               end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
+               if (start_pfn < end_pfn)
+                       nr_free_pages += end_pfn - start_pfn;
+       }
+
+       set_dma_reserve(nr_pages - nr_free_pages);
 #endif
 }

diff --git a/arch/x86/mm/memblock.c b/arch/x86/mm/memblock.c
index 4107c1a32b789db301ee7a85adb189735ea2f2b7..a9d0972df10afbd27bd38689e98c0ed4943c67dd 100644 (file)
--- a/arch/x86/mm/memblock.c
+++ b/arch/x86/mm/memblock.c
@@ -7,93 +7,6 @@
 #include <linux/mm.h>
 #include <linux/range.h>
 
-static __init struct range *find_range_array(int count)
-{
-       u64 end, size, mem;
-       struct range *range;
-
-       size = sizeof(struct range) * count;
-       end = memblock.current_limit;
-
-       mem = memblock_find_in_range(0, end, size, sizeof(struct range));
-       if (!mem)
-               panic("can not find more space for range array");
-
-       /*
-        * This range is tempoaray, so don't reserve it, it will not be
-        * overlapped because We will not alloccate new buffer before
-        * We discard this one
-        */
-       range = __va(mem);
-       memset(range, 0, size);
-
-       return range;
-}
-
-static u64 __init __memblock_x86_memory_in_range(u64 addr, u64 limit, bool get_free)
-{
-       int i, count;
-       struct range *range;
-       int nr_range;
-       u64 final_start, final_end;
-       u64 free_size;
-       struct memblock_region *r;
-
-       count = (memblock.reserved.cnt + memblock.memory.cnt) * 2;
-
-       range = find_range_array(count);
-       nr_range = 0;
-
-       addr = PFN_UP(addr);
-       limit = PFN_DOWN(limit);
-
-       for_each_memblock(memory, r) {
-               final_start = PFN_UP(r->base);
-               final_end = PFN_DOWN(r->base + r->size);
-               if (final_start >= final_end)
-                       continue;
-               if (final_start >= limit || final_end <= addr)
-                       continue;
-
-               nr_range = add_range(range, count, nr_range, final_start, final_end);
-       }
-       subtract_range(range, count, 0, addr);
-       subtract_range(range, count, limit, -1ULL);
-
-       /* Subtract memblock.reserved.region in range ? */
-       if (!get_free)
-               goto sort_and_count_them;
-       for_each_memblock(reserved, r) {
-               final_start = PFN_DOWN(r->base);
-               final_end = PFN_UP(r->base + r->size);
-               if (final_start >= final_end)
-                       continue;
-               if (final_start >= limit || final_end <= addr)
-                       continue;
-
-               subtract_range(range, count, final_start, final_end);
-       }
-
-sort_and_count_them:
-       nr_range = clean_sort_range(range, count);
-
-       free_size = 0;
-       for (i = 0; i < nr_range; i++)
-               free_size += range[i].end - range[i].start;
-
-       return free_size << PAGE_SHIFT;
-}
-
-u64 __init memblock_x86_free_memory_in_range(u64 addr, u64 limit)
-{
-       return __memblock_x86_memory_in_range(addr, limit, true);
-}
-
-u64 __init memblock_x86_memory_in_range(u64 addr, u64 limit)
-{
-       return __memblock_x86_memory_in_range(addr, limit, false);
-}
-
 void __init memblock_x86_reserve_range(u64 start, u64 end, char *name)
 {
        if (start == end)