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authorMichael Holzheu <holzheu@linux.vnet.ibm.com>2009-09-11 10:28:50 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2009-09-11 10:29:50 +0200
commit99b5e2d3d7ae8f5a2dba7a41a02ba7eb25523b3f (patch)
tree80177d3f079116272be2b9b25fcf3d1d54c7a5e5 /drivers
parent3f7cb51fac60618aa543058a90e668956d5fb518 (diff)
[S390] xpram: Remove checksum validation for suspend/resume
Currently in the suspend process checksums for the XPRAM partitions are created and stored. During the resume process it is checked, if the checksums are still the same. If this is not the case, a kernel panic is triggered. Unfortunately this prevents XPRAM from beeing used as suspend device, because in this case after the checksum has been created, the memory image is written to XPRAM and therefore the contents of the suspend partition is changed. In order to allow XPRAM to be used as suspend device, this patch removes the checksum validation. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/s390/block/xpram.c65
1 files changed, 0 insertions, 65 deletions
diff --git a/drivers/s390/block/xpram.c b/drivers/s390/block/xpram.c
index db442cd6621e..ee604e92a5fa 100644
--- a/drivers/s390/block/xpram.c
+++ b/drivers/s390/block/xpram.c
@@ -42,7 +42,6 @@
#include <linux/suspend.h>
#include <linux/platform_device.h>
#include <asm/uaccess.h>
-#include <asm/checksum.h>
#define XPRAM_NAME "xpram"
#define XPRAM_DEVS 1 /* one partition */
@@ -51,7 +50,6 @@
typedef struct {
unsigned int size; /* size of xpram segment in pages */
unsigned int offset; /* start page of xpram segment */
- unsigned int csum; /* partition checksum for suspend */
} xpram_device_t;
static xpram_device_t xpram_devices[XPRAM_MAX_DEVS];
@@ -387,58 +385,6 @@ out:
}
/*
- * Save checksums for all partitions.
- */
-static int xpram_save_checksums(void)
-{
- unsigned long mem_page;
- int rc, i;
-
- rc = 0;
- mem_page = (unsigned long) __get_free_page(GFP_KERNEL);
- if (!mem_page)
- return -ENOMEM;
- for (i = 0; i < xpram_devs; i++) {
- rc = xpram_page_in(mem_page, xpram_devices[i].offset);
- if (rc)
- goto fail;
- xpram_devices[i].csum = csum_partial((const void *) mem_page,
- PAGE_SIZE, 0);
- }
-fail:
- free_page(mem_page);
- return rc ? -ENXIO : 0;
-}
-
-/*
- * Verify checksums for all partitions.
- */
-static int xpram_validate_checksums(void)
-{
- unsigned long mem_page;
- unsigned int csum;
- int rc, i;
-
- rc = 0;
- mem_page = (unsigned long) __get_free_page(GFP_KERNEL);
- if (!mem_page)
- return -ENOMEM;
- for (i = 0; i < xpram_devs; i++) {
- rc = xpram_page_in(mem_page, xpram_devices[i].offset);
- if (rc)
- goto fail;
- csum = csum_partial((const void *) mem_page, PAGE_SIZE, 0);
- if (xpram_devices[i].csum != csum) {
- rc = -EINVAL;
- goto fail;
- }
- }
-fail:
- free_page(mem_page);
- return rc ? -ENXIO : 0;
-}
-
-/*
* Resume failed: Print error message and call panic.
*/
static void xpram_resume_error(const char *message)
@@ -458,21 +404,10 @@ static int xpram_restore(struct device *dev)
xpram_resume_error("xpram disappeared");
if (xpram_pages != xpram_highest_page_index() + 1)
xpram_resume_error("Size of xpram changed");
- if (xpram_validate_checksums())
- xpram_resume_error("Data of xpram changed");
return 0;
}
-/*
- * Save necessary state in suspend.
- */
-static int xpram_freeze(struct device *dev)
-{
- return xpram_save_checksums();
-}
-
static struct dev_pm_ops xpram_pm_ops = {
- .freeze = xpram_freeze,
.restore = xpram_restore,
};