| 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
| ||
|
Date: Wed, 6 Jun 2012 16:14:59 +0800
From: Lai Jiangshan <laijs@...fujitsu.com>
To: unlisted-recipients:; (no To-header on input)
Cc: Ingo Molnar <mingo@...e.hu>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Tejun Heo <tj@...nel.org>, Al Viro <viro@...iv.linux.org.uk>,
"H. Peter Anvin" <hpa@...ux.intel.com>,
Ian Campbell <ian.campbell@...rix.com>,
Paul Gortmaker <paul.gortmaker@...driver.com>,
Mel Gorman <mgorman@...e.de>, Michal Hocko <mhocko@...e.cz>,
linux-mm@...ck.org, linux-kernel@...r.kernel.org,
Lai Jiangshan <laijs@...fujitsu.com>
Subject: [PATCH 5/7] highmem: direct struct page_address_map allocation
Always allocate the struct page_address_map with the same index
(in page_address_maps) as kmap index.
it makes the allocation simpler.
pkmap_count[nr] == 0 <==> page_address_maps[nr] is free
pkmap_count[nr] != 0 <==> page_address_maps[nr] is in used
Signed-off-by: Lai Jiangshan <laijs@...fujitsu.com>
---
mm/highmem.c | 69 ++++++++++++++++++---------------------------------------
1 files changed, 22 insertions(+), 47 deletions(-)
diff --git a/mm/highmem.c b/mm/highmem.c
index bf7f168..bd2b9d3 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -92,7 +92,8 @@ static DECLARE_WAIT_QUEUE_HEAD(pkmap_map_wait);
do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
#endif
-static void set_high_page_address(struct page *page, void *virtual);
+static void set_high_page_map(struct page *page, unsigned int nr);
+static void clear_high_page_map(unsigned int nr);
static void flush_all_zero_pkmaps(void)
{
@@ -128,7 +129,7 @@ static void flush_all_zero_pkmaps(void)
pte_clear(&init_mm, (unsigned long)page_address(page),
&pkmap_page_table[i]);
- set_high_page_address(page, NULL);
+ clear_high_page_map(i);
need_flush = 1;
}
if (need_flush)
@@ -190,7 +191,7 @@ start:
&(pkmap_page_table[last_pkmap_nr]), mk_pte(page, kmap_prot));
pkmap_count[last_pkmap_nr] = 1;
- set_high_page_address(page, (void *)vaddr);
+ set_high_page_map(page, last_pkmap_nr);
return vaddr;
}
@@ -312,10 +313,7 @@ struct page_address_map {
struct list_head list;
};
-/*
- * page_address_map freelist, allocated from page_address_maps.
- */
-static struct list_head page_address_pool; /* freelist */
+static struct page_address_map page_address_maps[LAST_PKMAP];
/*
* Hash table bucket
@@ -365,58 +363,35 @@ done:
EXPORT_SYMBOL(page_address);
-/**
- * set_high_page_address - set a page's virtual address
- * @page: &struct page to set
- * @virtual: virtual address to use
- */
-static void set_high_page_address(struct page *page, void *virtual)
+static void set_high_page_map(struct page *page, unsigned int nr)
{
unsigned long flags;
- struct page_address_slot *pas;
- struct page_address_map *pam;
+ struct page_address_slot *pas = page_slot(page);
+ struct page_address_map *pam = &page_address_maps[nr];
- BUG_ON(!PageHighMem(page));
+ pam->page = page;
+ pam->virtual = (void *)PKMAP_ADDR(nr);
- pas = page_slot(page);
- if (virtual) { /* Add */
- BUG_ON(list_empty(&page_address_pool));
-
- pam = list_entry(page_address_pool.next,
- struct page_address_map, list);
- list_del(&pam->list);
+ spin_lock_irqsave(&pas->lock, flags);
+ list_add_tail(&pam->list, &pas->lh);
+ spin_unlock_irqrestore(&pas->lock, flags);
+}
- pam->page = page;
- pam->virtual = virtual;
+static void clear_high_page_map(unsigned int nr)
+{
+ unsigned long flags;
+ struct page_address_map *pam = &page_address_maps[nr];
+ struct page_address_slot *pas = page_slot(pam->page);
- spin_lock_irqsave(&pas->lock, flags);
- list_add_tail(&pam->list, &pas->lh);
- spin_unlock_irqrestore(&pas->lock, flags);
- } else { /* Remove */
- spin_lock_irqsave(&pas->lock, flags);
- list_for_each_entry(pam, &pas->lh, list) {
- if (pam->page == page) {
- list_del(&pam->list);
- spin_unlock_irqrestore(&pas->lock, flags);
- list_add_tail(&pam->list, &page_address_pool);
- goto done;
- }
- }
- spin_unlock_irqrestore(&pas->lock, flags);
- }
-done:
- return;
+ spin_lock_irqsave(&pas->lock, flags);
+ list_del(&pam->list);
+ spin_unlock_irqrestore(&pas->lock, flags);
}
-static struct page_address_map page_address_maps[LAST_PKMAP];
-
void __init page_address_init(void)
{
int i;
- INIT_LIST_HEAD(&page_address_pool);
- for (i = 0; i < ARRAY_SIZE(page_address_maps); i++)
- list_add(&page_address_maps[i].list, &page_address_pool);
for (i = 0; i < ARRAY_SIZE(page_address_htable); i++) {
INIT_LIST_HEAD(&page_address_htable[i].lh);
spin_lock_init(&page_address_htable[i].lock);
--
1.7.7
--
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/
Powered by blists - more mailing lists