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Commit a65ee5aa authored by Patrick Mochel's avatar Patrick Mochel
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[Power Mgmt] Merge pmdisk and swsusp pagedir handling. 

This embodies the core of the swsusp->pmdisk cleanups. Instead of using the
->dummy variable at the end of each pagedir for a linked list of the page
dirs, this uses a static array, which is kept in the empty space of the 
swsusp header.

There are 768 entries, and could be scaled up based on the size of the page
and the amount of room remaining. 768 should be enough anyway, since each
entry is a swp_entry_t to a page-length array of pages. With larger systems
and more memory come larger pages, so each page-sized array will 
automatically scale up. 

This replaces the read_suspend_image() and write_suspend_image() in swsusp
with the much more concise pmdisk versions (not that big of change at this
point) and fixes up the callers so software_resume() gets it right. 

Also, mark the helpers only used in swsusp as static again.
parent b6fb7271
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Showing with 99 additions and 255 deletions
kernel/power/pmdisk.c
View file @ a65ee5aa
...@@ -33,129 +33,20 @@ ...@@ -33,129 +33,20 @@
#include "power.h" #include "power.h"
extern asmlinkage int pmdisk_arch_suspend(int resume);
/* Variables to be preserved over suspend */
extern int pagedir_order_check;
extern int nr_copy_pages_check;
/* For resume= kernel option */ /* For resume= kernel option */
static char resume_file[256] = CONFIG_PM_DISK_PARTITION; static char resume_file[256] = CONFIG_PM_DISK_PARTITION;
static dev_t resume_device; static dev_t resume_device;
/* Local variables that should not be affected by save */
extern unsigned int nr_copy_pages;
/* Suspend pagedir is allocated before final copy, therefore it
must be freed after resume
Warning: this is evil. There are actually two pagedirs at time of
resume. One is "pagedir_save", which is empty frame allocated at
time of suspend, that must be freed. Second is "pagedir_nosave",
allocated at time of resume, that travels through memory not to
collide with anything.
*/
extern suspend_pagedir_t *pagedir_nosave;
extern suspend_pagedir_t *pagedir_save; extern suspend_pagedir_t *pagedir_save;
extern int pagedir_order;
extern struct swsusp_info swsusp_info;
/*
* XXX: We try to keep some more pages free so that I/O operations succeed
* without paging. Might this be more?
*/
#define PAGES_FOR_IO 512
/* /*
* Saving part... * Saving part...
*/ */
/* We memorize in swapfile_used what swap devices are used for suspension */
#define SWAPFILE_UNUSED 0
#define SWAPFILE_SUSPEND 1 /* This is the suspending device */
#define SWAPFILE_IGNORED 2 /* Those are other swap devices ignored for suspension */
extern int swsusp_swap_check(void);
extern void swsusp_swap_lock(void); extern void swsusp_swap_lock(void);
extern int swsusp_write_page(unsigned long addr, swp_entry_t * entry);
extern int swsusp_data_write(void);
extern void swsusp_data_free(void);
/**
* free_pagedir - Free pages used by the page directory.
*/
static void free_pagedir_entries(void)
{
int num = swsusp_info.pagedir_pages;
int i;
for (i = 0; i < num; i++)
swap_free(swsusp_info.pagedir[i]);
}
/**
* write_pagedir - Write the array of pages holding the page directory.
* @last: Last swap entry we write (needed for header).
*/
static int write_pagedir(void)
{
unsigned long addr = (unsigned long)pagedir_nosave;
int error = 0;
int n = SUSPEND_PD_PAGES(nr_copy_pages);
int i;
swsusp_info.pagedir_pages = n;
printk( "Writing pagedir (%d pages)\n", n);
for (i = 0; i < n && !error; i++, addr += PAGE_SIZE)
error = swsusp_write_page(addr,&swsusp_info.pagedir[i]);
return error;
}
extern void swsusp_init_header(void);
extern int swsusp_close_swap(void);
/**
* write_suspend_image - Write entire image and metadata.
*
*/
static int write_suspend_image(void)
{
int error;
swsusp_init_header();
if ((error = swsusp_data_write()))
goto FreeData;
if ((error = write_pagedir()))
goto FreePagedir;
if ((error = swsusp_close_swap()))
goto FreePagedir;
Done:
return error;
FreePagedir:
free_pagedir_entries();
FreeData:
swsusp_data_free();
goto Done;
}
extern void free_suspend_pagedir(unsigned long);
/** /**
* suspend_save_image - Prepare and write saved image to swap. * suspend_save_image - Prepare and write saved image to swap.
* *
...@@ -172,6 +63,7 @@ extern void free_suspend_pagedir(unsigned long); ...@@ -172,6 +63,7 @@ extern void free_suspend_pagedir(unsigned long);
static int suspend_save_image(void) static int suspend_save_image(void)
{ {
extern int write_suspend_image(void);
int error; int error;
device_resume(); device_resume();
swsusp_swap_lock(); swsusp_swap_lock();
...@@ -184,57 +76,10 @@ static int suspend_save_image(void) ...@@ -184,57 +76,10 @@ static int suspend_save_image(void)
/* More restore stuff */ /* More restore stuff */
extern struct block_device * resume_bdev; extern struct block_device * resume_bdev;
extern int bio_read_page(pgoff_t page_off, void * page);
extern int bio_write_page(pgoff_t page_off, void * page);
extern dev_t __init name_to_dev_t(const char *line); extern dev_t __init name_to_dev_t(const char *line);
static int __init read_pagedir(void)
{
unsigned long addr;
int i, n = swsusp_info.pagedir_pages;
int error = 0;
pagedir_order = get_bitmask_order(n);
addr =__get_free_pages(GFP_ATOMIC, pagedir_order);
if (!addr)
return -ENOMEM;
pagedir_nosave = (struct pbe *)addr;
pr_debug("pmdisk: Reading pagedir (%d Pages)\n",n);
for (i = 0; i < n && !error; i++, addr += PAGE_SIZE) {
unsigned long offset = swp_offset(swsusp_info.pagedir[i]);
if (offset)
error = bio_read_page(offset, (void *)addr);
else
error = -EFAULT;
}
if (error)
free_pages((unsigned long)pagedir_nosave,pagedir_order);
return error;
}
static int __init read_suspend_image(void)
{
extern int swsusp_data_read(void);
extern int swsusp_verify(void);
int error = 0;
if ((error = swsusp_verify()))
return error;
if ((error = read_pagedir()))
return error;
if ((error = swsusp_data_read())) {
free_pages((unsigned long)pagedir_nosave,pagedir_order);
}
return error;
}
/** /**
* pmdisk_write - Write saved memory image to swap. * pmdisk_write - Write saved memory image to swap.
...@@ -258,6 +103,7 @@ int pmdisk_write(void) ...@@ -258,6 +103,7 @@ int pmdisk_write(void)
int __init pmdisk_read(void) int __init pmdisk_read(void)
{ {
extern int read_suspend_image(void);
int error; int error;
if (!strlen(resume_file)) if (!strlen(resume_file))
...@@ -288,6 +134,7 @@ int __init pmdisk_read(void) ...@@ -288,6 +134,7 @@ int __init pmdisk_read(void)
int pmdisk_free(void) int pmdisk_free(void)
{ {
extern void free_suspend_pagedir(unsigned long this_pagedir);
pr_debug( "Freeing prev allocated pagedir\n" ); pr_debug( "Freeing prev allocated pagedir\n" );
free_suspend_pagedir((unsigned long)pagedir_save); free_suspend_pagedir((unsigned long)pagedir_save);
return 0; return 0;
......
kernel/power/swsusp.c
View file @ a65ee5aa
...@@ -122,16 +122,6 @@ struct swsusp_header { ...@@ -122,16 +122,6 @@ struct swsusp_header {
struct swsusp_info swsusp_info; struct swsusp_info swsusp_info;
struct link {
char dummy[PAGE_SIZE - sizeof(swp_entry_t)];
swp_entry_t next;
};
union diskpage {
union swap_header swh;
struct link link;
};
/* /*
* XXX: We try to keep some more pages free so that I/O operations succeed * XXX: We try to keep some more pages free so that I/O operations succeed
* without paging. Might this be more? * without paging. Might this be more?
...@@ -283,7 +273,7 @@ void swsusp_swap_lock(void) ...@@ -283,7 +273,7 @@ void swsusp_swap_lock(void)
* errors, though we need to eventually fix the damn code. * errors, though we need to eventually fix the damn code.
*/ */
int swsusp_write_page(unsigned long addr, swp_entry_t * loc) static int write_page(unsigned long addr, swp_entry_t * loc)
{ {
swp_entry_t entry; swp_entry_t entry;
int error = 0; int error = 0;
...@@ -309,7 +299,7 @@ int swsusp_write_page(unsigned long addr, swp_entry_t * loc) ...@@ -309,7 +299,7 @@ int swsusp_write_page(unsigned long addr, swp_entry_t * loc)
* Walk the list of used swap entries and free each one. * Walk the list of used swap entries and free each one.
*/ */
void swsusp_data_free(void) static void data_free(void)
{ {
swp_entry_t entry; swp_entry_t entry;
int i; int i;
...@@ -331,7 +321,7 @@ void swsusp_data_free(void) ...@@ -331,7 +321,7 @@ void swsusp_data_free(void)
* Walk the list of pages in the image and sync each one to swap. * Walk the list of pages in the image and sync each one to swap.
*/ */
int swsusp_data_write(void) static int data_write(void)
{ {
int error = 0; int error = 0;
int i; int i;
...@@ -340,7 +330,7 @@ int swsusp_data_write(void) ...@@ -340,7 +330,7 @@ int swsusp_data_write(void)
for (i = 0; i < nr_copy_pages && !error; i++) { for (i = 0; i < nr_copy_pages && !error; i++) {
if (!(i%100)) if (!(i%100))
printk( "." ); printk( "." );
error = swsusp_write_page((pagedir_nosave+i)->address, error = write_page((pagedir_nosave+i)->address,
&((pagedir_nosave+i)->swap_address)); &((pagedir_nosave+i)->swap_address));
} }
printk(" %d Pages done.\n",i); printk(" %d Pages done.\n",i);
...@@ -369,7 +359,7 @@ static void dump_info(void) ...@@ -369,7 +359,7 @@ static void dump_info(void)
} }
#endif #endif
void swsusp_init_header(void) static void init_header(void)
{ {
memset(&swsusp_info,0,sizeof(swsusp_info)); memset(&swsusp_info,0,sizeof(swsusp_info));
swsusp_info.version_code = LINUX_VERSION_CODE; swsusp_info.version_code = LINUX_VERSION_CODE;
...@@ -394,11 +384,11 @@ void swsusp_init_header(void) ...@@ -394,11 +384,11 @@ void swsusp_init_header(void)
static int write_header(swp_entry_t * entry) static int write_header(swp_entry_t * entry)
{ {
return swsusp_write_page((unsigned long)&swsusp_info,entry); return write_page((unsigned long)&swsusp_info,entry);
} }
int swsusp_close_swap(void) static int close_swap(void)
{ {
swp_entry_t entry; swp_entry_t entry;
int error; int error;
...@@ -412,50 +402,66 @@ int swsusp_close_swap(void) ...@@ -412,50 +402,66 @@ int swsusp_close_swap(void)
} }
/** /**
* write_suspend_image - Write entire image to disk. * free_pagedir - Free pages used by the page directory.
*
* After writing suspend signature to the disk, suspend may no
* longer fail: we have ready-to-run image in swap, and rollback
* would happen on next reboot -- corrupting data.
*
* Note: The buffer we allocate to use to write the suspend header is
* not freed; its not needed since the system is going down anyway
* (plus it causes an oops and I'm lazy^H^H^H^Htoo busy).
*/ */
static int write_suspend_image(void)
static void free_pagedir_entries(void)
{ {
int num = swsusp_info.pagedir_pages;
int i; int i;
for (i = 0; i < num; i++)
swap_free(swsusp_info.pagedir[i]);
}
/**
* write_pagedir - Write the array of pages holding the page directory.
* @last: Last swap entry we write (needed for header).
*/
static int write_pagedir(void)
{
unsigned long addr = (unsigned long)pagedir_nosave;
int error = 0; int error = 0;
swp_entry_t entry = { 0 }; int n = SUSPEND_PD_PAGES(nr_copy_pages);
int nr_pgdir_pages = SUSPEND_PD_PAGES(nr_copy_pages); int i;
union diskpage *cur, *buffer = (union diskpage *)get_zeroed_page(GFP_ATOMIC);
unsigned long addr;
if (!buffer) swsusp_info.pagedir_pages = n;
return -ENOMEM; printk( "Writing pagedir (%d pages)\n", n);
for (i = 0; i < n && !error; i++, addr += PAGE_SIZE)
error = write_page(addr,&swsusp_info.pagedir[i]);
return error;
}
swsusp_data_write(); /**
swsusp_init_header(); * write_suspend_image - Write entire image and metadata.
*
*/
printk( "Writing pagedir (%d pages): ", nr_pgdir_pages); int write_suspend_image(void)
addr = (unsigned long)pagedir_nosave; {
for (i=0; i<nr_pgdir_pages && !error; i++, addr += PAGE_SIZE) { int error;
cur = (union diskpage *)addr;
cur->link.next = entry;
printk( "." );
error = swsusp_write_page(addr,&entry);
}
printk("H");
BUG_ON (sizeof(union diskpage) != PAGE_SIZE);
BUG_ON (sizeof(struct link) != PAGE_SIZE);
swsusp_info.pagedir[0] = entry; init_header();
swsusp_close_swap(); if ((error = data_write()))
goto FreeData;
MDELAY(1000); if ((error = write_pagedir()))
return 0; goto FreePagedir;
if ((error = close_swap()))
goto FreePagedir;
Done:
return error;
FreePagedir:
free_pagedir_entries();
FreeData:
data_free();
goto Done;
} }
#ifdef CONFIG_HIGHMEM #ifdef CONFIG_HIGHMEM
struct highmem_page { struct highmem_page {
char *data; char *data;
...@@ -1258,7 +1264,7 @@ static int __init check_sig(void) ...@@ -1258,7 +1264,7 @@ static int __init check_sig(void)
} }
int __init swsusp_verify(void) int __init verify(void)
{ {
int error; int error;
...@@ -1275,7 +1281,7 @@ int __init swsusp_verify(void) ...@@ -1275,7 +1281,7 @@ int __init swsusp_verify(void)
* already did that. * already did that.
*/ */
int __init swsusp_data_read(void) static int __init data_read(void)
{ {
struct pbe * p; struct pbe * p;
int error; int error;
...@@ -1298,58 +1304,48 @@ int __init swsusp_data_read(void) ...@@ -1298,58 +1304,48 @@ int __init swsusp_data_read(void)
extern dev_t __init name_to_dev_t(const char *line); extern dev_t __init name_to_dev_t(const char *line);
static int __init __read_suspend_image(int noresume) static int __init read_pagedir(void)
{ {
union diskpage *cur; unsigned long addr;
swp_entry_t next; int i, n = swsusp_info.pagedir_pages;
int i, nr_pgdir_pages; int error = 0;
int error;
if ((error = swsusp_verify())) pagedir_order = get_bitmask_order(n);
return error;
cur = (union diskpage *)get_zeroed_page(GFP_ATOMIC); addr =__get_free_pages(GFP_ATOMIC, pagedir_order);
if (!cur) if (!addr)
return -ENOMEM; return -ENOMEM;
pagedir_nosave = (struct pbe *)addr;
#define PREPARENEXT \ pr_debug("pmdisk: Reading pagedir (%d Pages)\n",n);
{ next = cur->link.next; \
next.val = swp_offset(next); \
}
if (noresume) for (i = 0; i < n && !error; i++, addr += PAGE_SIZE) {
return 0; unsigned long offset = swp_offset(swsusp_info.pagedir[i]);
if (offset)
next = swsusp_info.pagedir[0]; error = bio_read_page(offset, (void *)addr);
next.val = swp_offset(next); else
error = -EFAULT;
pagedir_save = swsusp_info.suspend_pagedir; }
nr_copy_pages = swsusp_info.image_pages; if (error)
nr_pgdir_pages = SUSPEND_PD_PAGES(nr_copy_pages); free_pages((unsigned long)pagedir_nosave,pagedir_order);
pagedir_order = get_bitmask_order(nr_pgdir_pages); return error;
}
pagedir_nosave = (suspend_pagedir_t *)__get_free_pages(GFP_ATOMIC, pagedir_order);
if (!pagedir_nosave)
return -ENOMEM;
PRINTK( "%sReading pagedir, ", name_resume ); int __init read_suspend_image(void)
{
int error = 0;
/* We get pages in reverse order of saving! */ if ((error = verify()))
for (i=nr_pgdir_pages-1; i>=0; i--) { return error;
BUG_ON (!next.val); if ((error = read_pagedir()))
cur = (union diskpage *)((char *) pagedir_nosave)+i; return error;
if (bio_read_page(next.val, cur)) return -EIO; if ((error = data_read())) {
PREPARENEXT; free_pages((unsigned long)pagedir_nosave,pagedir_order);
} }
BUG_ON (next.val); return error;
error = swsusp_data_read();
if (!error)
printk( "|\n" );
return 0;
} }
static int __init read_suspend_image(const char * specialfile, int noresume) static int __init __read_suspend_image(const char * specialfile)
{ {
int error; int error;
char b[BDEVNAME_SIZE]; char b[BDEVNAME_SIZE];
...@@ -1359,7 +1355,7 @@ static int __init read_suspend_image(const char * specialfile, int noresume) ...@@ -1359,7 +1355,7 @@ static int __init read_suspend_image(const char * specialfile, int noresume)
resume_bdev = open_by_devnum(resume_device, FMODE_READ); resume_bdev = open_by_devnum(resume_device, FMODE_READ);
if (!IS_ERR(resume_bdev)) { if (!IS_ERR(resume_bdev)) {
set_blocksize(resume_bdev, PAGE_SIZE); set_blocksize(resume_bdev, PAGE_SIZE);
error = __read_suspend_image(noresume); error = read_suspend_image();
blkdev_put(resume_bdev); blkdev_put(resume_bdev);
} else } else
error = PTR_ERR(resume_bdev); error = PTR_ERR(resume_bdev);
...@@ -1391,9 +1387,10 @@ static int __init software_resume(void) ...@@ -1391,9 +1387,10 @@ static int __init software_resume(void)
printk( "%s", name_resume ); printk( "%s", name_resume );
if (resume_status == NORESUME) { if (resume_status == NORESUME) {
if(resume_file[0]) /*
read_suspend_image(resume_file, 1); * FIXME: If noresume is specified, we need to handle by finding
printk( "disabled\n" ); * the right partition and resettting the signature.
*/
return 0; return 0;
} }
MDELAY(1000); MDELAY(1000);
...@@ -1407,7 +1404,7 @@ static int __init software_resume(void) ...@@ -1407,7 +1404,7 @@ static int __init software_resume(void)
} }
printk( "resuming from %s\n", resume_file); printk( "resuming from %s\n", resume_file);
if (read_suspend_image(resume_file, 0)) if (__read_suspend_image(resume_file))
goto read_failure; goto read_failure;
/* FIXME: Should we stop processes here, just to be safer? */ /* FIXME: Should we stop processes here, just to be safer? */
disable_nonboot_cpus(); disable_nonboot_cpus();
......
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