linux/arch/arm/plat-samsung/pm-check.c

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/* linux/arch/arm/plat-s3c/pm-check.c
* originally in linux/arch/arm/plat-s3c24xx/pm.c
*
* Copyright (c) 2004-2008 Simtec Electronics
* http://armlinux.simtec.co.uk
* Ben Dooks <ben@simtec.co.uk>
*
* S3C Power Mangament - suspend/resume memory corruptiuon check.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/suspend.h>
#include <linux/init.h>
#include <linux/crc32.h>
#include <linux/ioport.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 09:04:11 +01:00
#include <linux/slab.h>
#include <plat/pm.h>
#if CONFIG_SAMSUNG_PM_CHECK_CHUNKSIZE < 1
#error CONFIG_SAMSUNG_PM_CHECK_CHUNKSIZE must be a positive non-zero value
#endif
/* suspend checking code...
*
* this next area does a set of crc checks over all the installed
* memory, so the system can verify if the resume was ok.
*
* CONFIG_SAMSUNG_PM_CHECK_CHUNKSIZE defines the block-size for the CRC,
* increasing it will mean that the area corrupted will be less easy to spot,
* and reducing the size will cause the CRC save area to grow
*/
#define CHECK_CHUNKSIZE (CONFIG_SAMSUNG_PM_CHECK_CHUNKSIZE * 1024)
static u32 crc_size; /* size needed for the crc block */
static u32 *crcs; /* allocated over suspend/resume */
typedef u32 *(run_fn_t)(struct resource *ptr, u32 *arg);
/* s3c_pm_run_res
*
* go through the given resource list, and look for system ram
*/
static void s3c_pm_run_res(struct resource *ptr, run_fn_t fn, u32 *arg)
{
while (ptr != NULL) {
if (ptr->child != NULL)
s3c_pm_run_res(ptr->child, fn, arg);
if ((ptr->flags & IORESOURCE_MEM) &&
strcmp(ptr->name, "System RAM") == 0) {
S3C_PMDBG("Found system RAM at %08lx..%08lx\n",
(unsigned long)ptr->start,
(unsigned long)ptr->end);
arg = (fn)(ptr, arg);
}
ptr = ptr->sibling;
}
}
static void s3c_pm_run_sysram(run_fn_t fn, u32 *arg)
{
s3c_pm_run_res(&iomem_resource, fn, arg);
}
static u32 *s3c_pm_countram(struct resource *res, u32 *val)
{
u32 size = (u32)resource_size(res);
size += CHECK_CHUNKSIZE-1;
size /= CHECK_CHUNKSIZE;
S3C_PMDBG("Area %08lx..%08lx, %d blocks\n",
(unsigned long)res->start, (unsigned long)res->end, size);
*val += size * sizeof(u32);
return val;
}
/* s3c_pm_prepare_check
*
* prepare the necessary information for creating the CRCs. This
* must be done before the final save, as it will require memory
* allocating, and thus touching bits of the kernel we do not
* know about.
*/
void s3c_pm_check_prepare(void)
{
crc_size = 0;
s3c_pm_run_sysram(s3c_pm_countram, &crc_size);
S3C_PMDBG("s3c_pm_prepare_check: %u checks needed\n", crc_size);
crcs = kmalloc(crc_size+4, GFP_KERNEL);
if (crcs == NULL)
printk(KERN_ERR "Cannot allocated CRC save area\n");
}
static u32 *s3c_pm_makecheck(struct resource *res, u32 *val)
{
unsigned long addr, left;
for (addr = res->start; addr < res->end;
addr += CHECK_CHUNKSIZE) {
left = res->end - addr;
if (left > CHECK_CHUNKSIZE)
left = CHECK_CHUNKSIZE;
*val = crc32_le(~0, phys_to_virt(addr), left);
val++;
}
return val;
}
/* s3c_pm_check_store
*
* compute the CRC values for the memory blocks before the final
* sleep.
*/
void s3c_pm_check_store(void)
{
if (crcs != NULL)
s3c_pm_run_sysram(s3c_pm_makecheck, crcs);
}
/* in_region
*
* return TRUE if the area defined by ptr..ptr+size contains the
* what..what+whatsz
*/
static inline int in_region(void *ptr, int size, void *what, size_t whatsz)
{
if ((what+whatsz) < ptr)
return 0;
if (what > (ptr+size))
return 0;
return 1;
}
/**
* s3c_pm_runcheck() - helper to check a resource on restore.
* @res: The resource to check
* @vak: Pointer to list of CRC32 values to check.
*
* Called from the s3c_pm_check_restore() via s3c_pm_run_sysram(), this
* function runs the given memory resource checking it against the stored
* CRC to ensure that memory is restored. The function tries to skip as
* many of the areas used during the suspend process.
*/
static u32 *s3c_pm_runcheck(struct resource *res, u32 *val)
{
unsigned long addr;
unsigned long left;
void *stkpage;
void *ptr;
u32 calc;
stkpage = (void *)((u32)&calc & ~PAGE_MASK);
for (addr = res->start; addr < res->end;
addr += CHECK_CHUNKSIZE) {
left = res->end - addr;
if (left > CHECK_CHUNKSIZE)
left = CHECK_CHUNKSIZE;
ptr = phys_to_virt(addr);
if (in_region(ptr, left, stkpage, 4096)) {
S3C_PMDBG("skipping %08lx, has stack in\n", addr);
goto skip_check;
}
if (in_region(ptr, left, crcs, crc_size)) {
S3C_PMDBG("skipping %08lx, has crc block in\n", addr);
goto skip_check;
}
/* calculate and check the checksum */
calc = crc32_le(~0, ptr, left);
if (calc != *val) {
printk(KERN_ERR "Restore CRC error at "
"%08lx (%08x vs %08x)\n", addr, calc, *val);
S3C_PMDBG("Restore CRC error at %08lx (%08x vs %08x)\n",
addr, calc, *val);
}
skip_check:
val++;
}
return val;
}
/**
* s3c_pm_check_restore() - memory check called on resume
*
* check the CRCs after the restore event and free the memory used
* to hold them
*/
void s3c_pm_check_restore(void)
{
if (crcs != NULL)
s3c_pm_run_sysram(s3c_pm_runcheck, crcs);
}
/**
* s3c_pm_check_cleanup() - free memory resources
*
* Free the resources that where allocated by the suspend
* memory check code. We do this separately from the
* s3c_pm_check_restore() function as we cannot call any
* functions that might sleep during that resume.
*/
void s3c_pm_check_cleanup(void)
{
kfree(crcs);
crcs = NULL;
}