linux-kernel - [PATCH 16/31] lmb: Add lmb_free_memory

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1269830604-26214-17-git-send-email-yinghai@kernel.org>
Date:	Sun, 28 Mar 2010 19:43:09 -0700
From:	Yinghai Lu <yinghai@...nel.org>
To:	Ingo Molnar <mingo@...e.hu>, Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	David Miller <davem@...emloft.net>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Johannes Weiner <hannes@...xchg.org>, linux-kernel@...r.kernel.org,
	linux-arch@...r.kernel.org, Yinghai Lu <yinghai@...nel.org>
Subject: [PATCH 16/31] lmb: Add lmb_free_memory_size()

It will return free memory size in specified range.

We can not use memory_size - reserved_size here, because some reserved area
may not be in the scope of lmb.memory.region.

Use lmb.memory.region subtracting lmb.reserved.region to get free range array.
then count size of all free ranges.

Signed-off-by: Yinghai Lu <yinghai@...nel.org>
---
 include/linux/lmb.h |    1 +
 mm/lmb.c            |   51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 0 deletions(-)

diff --git a/include/linux/lmb.h b/include/linux/lmb.h
index 019520a..51a8653 100644
--- a/include/linux/lmb.h
+++ b/include/linux/lmb.h
@@ -101,6 +101,7 @@ int get_free_all_memory_range(struct range **rangep, int nodeid);
 void lmb_register_active_regions(int nid, unsigned long start_pfn,
 					 unsigned long last_pfn);
 u64 lmb_hole_size(u64 start, u64 end);
+u64 lmb_free_memory_size(u64 addr, u64 limit);
 
 #include <asm/lmb.h>
 
diff --git a/mm/lmb.c b/mm/lmb.c
index addfcb1..233c40d 100644
--- a/mm/lmb.c
+++ b/mm/lmb.c
@@ -756,6 +756,57 @@ void __init lmb_to_bootmem(u64 start, u64 end)
 }
 #endif
 
+u64 __init lmb_free_memory_size(u64 addr, u64 limit)
+{
+	int i, count;
+	struct range *range;
+	int nr_range;
+	u64 final_start, final_end;
+	u64 free_size;
+
+	count = lmb.reserved.cnt * 2;
+
+	range = find_range_array(count);
+	nr_range = 0;
+
+	addr = PFN_UP(addr);
+	limit = PFN_DOWN(limit);
+
+	for (i = 0; i < lmb.memory.cnt; i++) {
+		struct lmb_property *r = &lmb.memory.region[i];
+
+		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);
+	for (i = 0; i < lmb.reserved.cnt; i++) {
+		struct lmb_property *r = &lmb.reserved.region[i];
+
+		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);
+	}
+	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;
+}
+
 static int __init find_overlapped_early(u64 start, u64 end)
 {
 	int i;
-- 
1.6.4.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/