linux-kernel - [RFC v2 1/5] memblock: Introduce a for_each_reserved_mem

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: <1375465467-40488-2-git-send-email-nzimmer@sgi.com>
Date:	Fri,  2 Aug 2013 12:44:23 -0500
From:	Nathan Zimmer <nzimmer@....com>
To:	hpa@...or.com, mingo@...nel.org
Cc:	linux-kernel@...r.kernel.org, linux-mm@...ck.org, holt@....com,
	nzimmer@....com, rob@...dley.net, travis@....com,
	daniel@...ascale-asia.com, akpm@...ux-foundation.org,
	gregkh@...uxfoundation.org, yinghai@...nel.org, mgorman@...e.de
Subject: [RFC v2 1/5] memblock: Introduce a for_each_reserved_mem_region iterator.

From: Robin Holt <holt@....com>

As part of initializing struct page's in 2MiB chunks, we noticed that
at the end of free_all_bootmem(), there was nothing which had forced
the reserved/allocated 4KiB pages to be initialized.

This helper function will be used for that expansion.

Signed-off-by: Robin Holt <holt@....com>
Signed-off-by: Nathan Zimmer <nzimmer@....com>
To: "H. Peter Anvin" <hpa@...or.com>
To: Ingo Molnar <mingo@...nel.org>
Cc: Linux Kernel <linux-kernel@...r.kernel.org>
Cc: Linux MM <linux-mm@...ck.org>
Cc: Rob Landley <rob@...dley.net>
Cc: Mike Travis <travis@....com>
Cc: Daniel J Blueman <daniel@...ascale-asia.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>
Cc: Greg KH <gregkh@...uxfoundation.org>
Cc: Yinghai Lu <yinghai@...nel.org>
Cc: Mel Gorman <mgorman@...e.de>
---
 include/linux/memblock.h | 18 ++++++++++++++++++
 mm/memblock.c            | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index f388203..e99bbd1 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -118,6 +118,24 @@ void __next_free_mem_range_rev(u64 *idx, int nid, phys_addr_t *out_start,
 	     i != (u64)ULLONG_MAX;					\
 	     __next_free_mem_range_rev(&i, nid, p_start, p_end, p_nid))
 
+void __next_reserved_mem_region(u64 *idx, phys_addr_t *out_start,
+			       phys_addr_t *out_end);
+
+/**
+ * for_earch_reserved_mem_region - iterate over all reserved memblock areas
+ * @i: u64 used as loop variable
+ * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ *
+ * Walks over reserved areas of memblock in. Available as soon as memblock
+ * is initialized.
+ */
+#define for_each_reserved_mem_region(i, p_start, p_end)			\
+	for (i = 0UL,							\
+	     __next_reserved_mem_region(&i, p_start, p_end);		\
+	     i != (u64)ULLONG_MAX;					\
+	     __next_reserved_mem_region(&i, p_start, p_end))
+
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 int memblock_set_node(phys_addr_t base, phys_addr_t size, int nid);
 
diff --git a/mm/memblock.c b/mm/memblock.c
index c5fad93..0d7d6e7 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -564,6 +564,38 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
 }
 
 /**
+ * __next_reserved_mem_region - next function for for_each_reserved_region()
+ * @idx: pointer to u64 loop variable
+ * @out_start: ptr to phys_addr_t for start address of the region, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the region, can be %NULL
+ *
+ * Iterate over all reserved memory regions.
+ */
+void __init_memblock __next_reserved_mem_region(u64 *idx,
+					   phys_addr_t *out_start,
+					   phys_addr_t *out_end)
+{
+	struct memblock_type *rsv = &memblock.reserved;
+
+	if (*idx >= 0 && *idx < rsv->cnt) {
+		struct memblock_region *r = &rsv->regions[*idx];
+		phys_addr_t base = r->base;
+		phys_addr_t size = r->size;
+
+		if (out_start)
+			*out_start = base;
+		if (out_end)
+			*out_end = base + size - 1;
+
+		*idx += 1;
+		return;
+	}
+
+	/* signal end of iteration */
+	*idx = ULLONG_MAX;
+}
+
+/**
  * __next_free_mem_range - next function for for_each_free_mem_range()
  * @idx: pointer to u64 loop variable
  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
-- 
1.8.2.1

--
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/