linux-kernel - [PATCH 2/2] agp/intel: use dma_alloc_coherent for special cursor 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>] [day] [month] [year] [list]

Date:	Tue, 24 Mar 2009 10:59:39 -0700
From:	Jeremy Fitzhardinge <jeremy@...p.org>
To:	Dave Airlie <airlied@...ux.ie>
CC:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	dri-devel <dri-devel@...ts.sourceforge.net>
Subject: [PATCH 2/2] agp/intel: use dma_alloc_coherent for special cursor
 memory

Impact: make i810 work under Xen

Given that i810 wants special physically contiguous memory for its
cursor, we should allocate it with dma_alloc_coherent, which will
give us memory with the right properties.  This is particularly for
Xen, which won't normally give us physically contiuous memory.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@...rix.com>
Cc: David Airlie <airlied@...ux.ie>

diff --git a/drivers/char/agp/intel-agp.c b/drivers/char/agp/intel-agp.c
index 4373adb..8ba6808 100644
--- a/drivers/char/agp/intel-agp.c
+++ b/drivers/char/agp/intel-agp.c
@@ -244,33 +244,29 @@ static void intel_i810_agp_enable(struct agp_bridge_data *bridge, u32 mode)
 /* Exists to support ARGB cursors */
 static void *i8xx_alloc_pages(void)
 {
-	struct page *page;
-
-	page = alloc_pages(GFP_KERNEL | GFP_DMA32, 2);
-	if (page == NULL)
+	void *addr;
+	dma_addr_t _d;
+	
+	addr = dma_alloc_coherent(NULL, 4 * PAGE_SIZE, &_d, GFP_KERNEL);
+	if (addr == NULL)
 		return NULL;
 
-	if (set_pages_uc(page, 4) < 0) {
-		set_pages_wb(page, 4);
-		__free_pages(page, 2);
+	if (set_memory_uc((unsigned long)addr, 4) < 0) {
+		set_memory_wb((unsigned long)addr, 4);
+		dma_free_coherent(NULL, 4 * PAGE_SIZE, addr, _d);
 		return NULL;
 	}
-	get_page(page);
 	atomic_inc(&agp_bridge->current_memory_agp);
-	return page_address(page);
+	return addr;
 }
 
 static void i8xx_destroy_pages(void *addr)
 {
-	struct page *page;
-
 	if (addr == NULL)
 		return;
 
-	page = virt_to_page(addr);
-	set_pages_wb(page, 4);
-	put_page(page);
-	__free_pages(page, 2);
+	set_memory_wb((unsigned long)addr, 4);
+	dma_free_coherent(NULL, 4 * PAGE_SIZE, addr, virt_to_bus(addr));
 	atomic_dec(&agp_bridge->current_memory_agp);
 }
 


--
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/