lkml.org 
[lkml]   [2007]   [Mar]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 16/20] swsusp: do not use virt_to_page on kernel data address


o virt_to_page() call should be used on kernel linear addresses and not
on kernel text and data addresses. Swsusp code uses it on kernel data
(statically allocated swsusp_header).

o Allocate swsusp_header dynamically so that virt_to_page() can be used
safely.

o I am changing this because in next few patches, __pa() on x86_64 will
no longer support kernel text and data addresses and hibernation breaks.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---
kernel/power/swap.c | 42 +++++++++++++++++++++++++++---------------
1 file changed, 27 insertions(+), 15 deletions(-)
diff -puN kernel/power/swap.c~swsusp-do-not-use-virt_to_page-on-kernel-data-addr kernel/power/swap.c
--- linux-2.6.21-rc2-reloc/kernel/power/swap.c~swsusp-do-not-use-virt_to_page-on-kernel-data-addr 2007-03-07 01:30:43.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/kernel/power/swap.c 2007-03-07 01:30:43.000000000 +0530
@@ -33,12 +33,14 @@ extern char resume_file[];

#define SWSUSP_SIG "S1SUSPEND"

-static struct swsusp_header {
+struct swsusp_header {
char reserved[PAGE_SIZE - 20 - sizeof(sector_t)];
sector_t image;
char orig_sig[10];
char sig[10];
-} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header;
+} __attribute__((packed));
+
+static struct swsusp_header *swsusp_header;

/*
* General things
@@ -141,14 +143,14 @@ static int mark_swapfiles(sector_t start
{
int error;

- bio_read_page(swsusp_resume_block, &swsusp_header, NULL);
- if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||
- !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {
- memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);
- memcpy(swsusp_header.sig,SWSUSP_SIG, 10);
- swsusp_header.image = start;
+ bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+ if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
+ !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
+ memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
+ memcpy(swsusp_header->sig,SWSUSP_SIG, 10);
+ swsusp_header->image = start;
error = bio_write_page(swsusp_resume_block,
- &swsusp_header, NULL);
+ swsusp_header, NULL);
} else {
printk(KERN_ERR "swsusp: Swap header not found!\n");
error = -ENODEV;
@@ -564,7 +566,7 @@ int swsusp_read(void)
if (error < PAGE_SIZE)
return error < 0 ? error : -EFAULT;
header = (struct swsusp_info *)data_of(snapshot);
- error = get_swap_reader(&handle, swsusp_header.image);
+ error = get_swap_reader(&handle, swsusp_header->image);
if (!error)
error = swap_read_page(&handle, header, NULL);
if (!error)
@@ -591,17 +593,17 @@ int swsusp_check(void)
resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
if (!IS_ERR(resume_bdev)) {
set_blocksize(resume_bdev, PAGE_SIZE);
- memset(&swsusp_header, 0, sizeof(swsusp_header));
+ memset(swsusp_header, 0, sizeof(PAGE_SIZE));
error = bio_read_page(swsusp_resume_block,
- &swsusp_header, NULL);
+ swsusp_header, NULL);
if (error)
return error;

- if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {
- memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);
+ if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {
+ memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
/* Reset swap signature now */
error = bio_write_page(swsusp_resume_block,
- &swsusp_header, NULL);
+ swsusp_header, NULL);
} else {
return -EINVAL;
}
@@ -632,3 +634,13 @@ void swsusp_close(void)

blkdev_put(resume_bdev);
}
+
+static int swsusp_header_init(void)
+{
+ swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
+ if (!swsusp_header)
+ panic("Could not allocate memory for swsusp_header\n");
+ return 0;
+}
+
+core_initcall(swsusp_header_init);
_
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2007-03-07 08:41    [from the cache]
©2003-2011 Jasper Spaans