extern const void __nosave_begin, __nosave_end;
/* Variables to be preserved over suspend */
-static int pagedir_order_check;
static int nr_copy_pages_check;
extern char resume_file[];
-static dev_t resume_device;
+
/* Local variables that should not be affected by save */
unsigned int nr_copy_pages __nosavedata = 0;
*/
suspend_pagedir_t *pagedir_nosave __nosavedata = NULL;
static suspend_pagedir_t *pagedir_save;
-static int pagedir_order __nosavedata = 0;
#define SWSUSP_SIG "S1SUSPEND"
struct inode *inode = file->f_dentry->d_inode;
return S_ISBLK(inode->i_mode) &&
- resume_device == MKDEV(imajor(inode), iminor(inode));
+ swsusp_resume_device == MKDEV(imajor(inode), iminor(inode));
}
static int swsusp_swap_check(void) /* This is called before saving image */
swap_list_unlock();
}
-
-
/**
* write_swap_page - Write one page to a fresh swap location.
* @addr: Address we're writing.
* This is a partial improvement, since we will at least return other
* errors, though we need to eventually fix the damn code.
*/
-
static int write_page(unsigned long addr, swp_entry_t * loc)
{
swp_entry_t entry;
return error;
}
-
/**
* data_free - Free the swap entries used by the saved image.
*
* Walk the list of used swap entries and free each one.
* This is only used for cleanup when suspend fails.
*/
-
static void data_free(void)
{
swp_entry_t entry;
}
}
-
/**
* data_write - Write saved image to swap.
*
* Walk the list of pages in the image and sync each one to swap.
*/
-
static int data_write(void)
{
- int error = 0;
- int i;
+ int error = 0, i = 0;
unsigned int mod = nr_copy_pages / 100;
+ struct pbe *p;
if (!mod)
mod = 1;
printk( "Writing data to swap (%d pages)... ", nr_copy_pages );
- for (i = 0; i < nr_copy_pages && !error; i++) {
+ for_each_pbe(p, pagedir_nosave) {
if (!(i%mod))
printk( "\b\b\b\b%3d%%", i / mod );
- error = write_page((pagedir_nosave+i)->address,
- &((pagedir_nosave+i)->swap_address));
+ if ((error = write_page(p->address, &(p->swap_address))))
+ return error;
+ i++;
}
printk("\b\b\b\bdone\n");
return error;
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.num_physpages = num_physpages;
- memcpy(&swsusp_info.uts,&system_utsname,sizeof(system_utsname));
+ memcpy(&swsusp_info.uts, &system_utsname, sizeof(system_utsname));
swsusp_info.suspend_pagedir = pagedir_nosave;
swsusp_info.cpus = num_online_cpus();
swsusp_info.image_pages = nr_copy_pages;
- dump_info();
}
static int close_swap(void)
swp_entry_t entry;
int error;
- error = write_page((unsigned long)&swsusp_info,&entry);
+ dump_info();
+ error = write_page((unsigned long)&swsusp_info, &entry);
if (!error) {
printk( "S" );
error = mark_swapfiles(entry);
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;
+ unsigned n = 0;
+ struct pbe * pbe;
+
+ printk( "Writing pagedir...");
+ for_each_pb_page(pbe, pagedir_nosave) {
+ if ((error = write_page((unsigned long)pbe, &swsusp_info.pagedir[n++])))
+ return error;
+ }
swsusp_info.pagedir_pages = n;
- 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]);
+ printk("done (%u pages)\n", n);
return error;
}
struct zone *zone;
unsigned long zone_pfn;
struct pbe * pbe = pagedir_nosave;
- int to_copy = nr_copy_pages;
+ pr_debug("copy_data_pages(): pages to copy: %d\n", nr_copy_pages);
for_each_zone(zone) {
if (is_highmem(zone))
continue;
if (saveable(zone, &zone_pfn)) {
struct page * page;
page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
+ BUG_ON(!pbe);
pbe->orig_address = (long) page_address(page);
/* copy_page is not usable for copying task structs. */
memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE);
- pbe++;
- to_copy--;
+ pbe = pbe->next;
}
}
}
- BUG_ON(to_copy);
+ BUG_ON(pbe);
}
/**
- * calc_order - Determine the order of allocation needed for pagedir_save.
- *
- * This looks tricky, but is just subtle. Please fix it some time.
- * Since there are %nr_copy_pages worth of pages in the snapshot, we need
- * to allocate enough contiguous space to hold
- * (%nr_copy_pages * sizeof(struct pbe)),
- * which has the saved/orig locations of the page..
- *
- * SUSPEND_PD_PAGES() tells us how many pages we need to hold those
- * structures, then we call get_bitmask_order(), which will tell us the
- * last bit set in the number, starting with 1. (If we need 30 pages, that
- * is 0x0000001e in hex. The last bit is the 5th, which is the order we
- * would use to allocate 32 contiguous pages).
- *
- * Since we also need to save those pages, we add the number of pages that
- * we need to nr_copy_pages, and in case of an overflow, do the
- * calculation again to update the number of pages needed.
- *
- * With this model, we will tend to waste a lot of memory if we just cross
- * an order boundary. Plus, the higher the order of allocation that we try
- * to do, the more likely we are to fail in a low-memory situtation
- * (though we're unlikely to get this far in such a case, since swsusp
- * requires half of memory to be free anyway).
+ * calc_nr - Determine the number of pages needed for a pbe list.
*/
-
-static void calc_order(void)
+static int calc_nr(int nr_copy)
{
- int diff = 0;
- int order = 0;
+ int extra = 0;
+ int mod = !!(nr_copy % PBES_PER_PAGE);
+ int diff = (nr_copy / PBES_PER_PAGE) + mod;
do {
- diff = get_bitmask_order(SUSPEND_PD_PAGES(nr_copy_pages)) - order;
- if (diff) {
- order += diff;
- nr_copy_pages += 1 << diff;
- }
- } while(diff);
- pagedir_order = order;
+ extra += diff;
+ nr_copy += diff;
+ mod = !!(nr_copy % PBES_PER_PAGE);
+ diff = (nr_copy / PBES_PER_PAGE) + mod - extra;
+ } while (diff > 0);
+
+ return nr_copy;
}
+/**
+ * free_pagedir - free pages allocated with alloc_pagedir()
+ */
+
+static inline void free_pagedir(struct pbe *pblist)
+{
+ struct pbe *pbe;
+
+ while (pblist) {
+ pbe = (pblist + PB_PAGE_SKIP)->next;
+ free_page((unsigned long)pblist);
+ pblist = pbe;
+ }
+}
+
+/**
+ * fill_pb_page - Create a list of PBEs on a given memory page
+ */
+
+static inline void fill_pb_page(struct pbe *pbpage)
+{
+ struct pbe *p;
+
+ p = pbpage;
+ pbpage += PB_PAGE_SKIP;
+ do
+ p->next = p + 1;
+ while (++p < pbpage);
+}
+
+/**
+ * create_pbe_list - Create a list of PBEs on top of a given chain
+ * of memory pages allocated with alloc_pagedir()
+ */
+
+static void create_pbe_list(struct pbe *pblist, unsigned nr_pages)
+{
+ struct pbe *pbpage, *p;
+ unsigned num = PBES_PER_PAGE;
+
+ for_each_pb_page (pbpage, pblist) {
+ if (num >= nr_pages)
+ break;
+
+ fill_pb_page(pbpage);
+ num += PBES_PER_PAGE;
+ }
+ if (pbpage) {
+ for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++)
+ p->next = p + 1;
+ p->next = NULL;
+ }
+ pr_debug("create_pbe_list(): initialized %d PBEs\n", num);
+}
/**
* alloc_pagedir - Allocate the page directory.
*
- * First, determine exactly how many contiguous pages we need and
+ * First, determine exactly how many pages we need and
* allocate them.
+ *
+ * We arrange the pages in a chain: each page is an array of PBES_PER_PAGE
+ * struct pbe elements (pbes) and the last element in the page points
+ * to the next page.
+ *
+ * On each page we set up a list of struct_pbe elements.
*/
-static int alloc_pagedir(void)
+static struct pbe * alloc_pagedir(unsigned nr_pages)
{
- calc_order();
- pagedir_save = (suspend_pagedir_t *)__get_free_pages(GFP_ATOMIC | __GFP_COLD,
- pagedir_order);
- if (!pagedir_save)
- return -ENOMEM;
- memset(pagedir_save, 0, (1 << pagedir_order) * PAGE_SIZE);
- pagedir_nosave = pagedir_save;
- return 0;
+ unsigned num;
+ struct pbe *pblist, *pbe;
+
+ if (!nr_pages)
+ return NULL;
+
+ pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages);
+ pblist = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
+ for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages;
+ pbe = pbe->next, num += PBES_PER_PAGE) {
+ pbe += PB_PAGE_SKIP;
+ pbe->next = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
+ }
+ if (!pbe) { /* get_zeroed_page() failed */
+ free_pagedir(pblist);
+ pblist = NULL;
+ }
+ return pblist;
}
/**
static void free_image_pages(void)
{
struct pbe * p;
- int i;
- p = pagedir_save;
- for (i = 0, p = pagedir_save; i < nr_copy_pages; i++, p++) {
+ for_each_pbe(p, pagedir_save) {
if (p->address) {
ClearPageNosave(virt_to_page(p->address));
free_page(p->address);
/**
* alloc_image_pages - Allocate pages for the snapshot.
- *
*/
static int alloc_image_pages(void)
{
struct pbe * p;
- int i;
- for (i = 0, p = pagedir_save; i < nr_copy_pages; i++, p++) {
+ for_each_pbe(p, pagedir_save) {
p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
if (!p->address)
return -ENOMEM;
BUG_ON(PageNosave(virt_to_page(pagedir_save)));
BUG_ON(PageNosaveFree(virt_to_page(pagedir_save)));
free_image_pages();
- free_pages((unsigned long) pagedir_save, pagedir_order);
+ free_pagedir(pagedir_save);
}
if (!enough_swap())
return -ENOSPC;
- if ((error = alloc_pagedir())) {
+ nr_copy_pages = calc_nr(nr_copy_pages);
+
+ if (!(pagedir_save = alloc_pagedir(nr_copy_pages))) {
printk(KERN_ERR "suspend: Allocating pagedir failed.\n");
- return error;
+ return -ENOMEM;
}
+ create_pbe_list(pagedir_save, nr_copy_pages);
+ pagedir_nosave = pagedir_save;
if ((error = alloc_image_pages())) {
printk(KERN_ERR "suspend: Allocating image pages failed.\n");
swsusp_free();
}
nr_copy_pages_check = nr_copy_pages;
- pagedir_order_check = pagedir_order;
return 0;
}
drain_local_pages();
count_data_pages();
- printk("swsusp: Need to copy %u pages\n",nr_copy_pages);
+ printk("swsusp: Need to copy %u pages\n", nr_copy_pages);
error = swsusp_alloc();
if (error)
* at resume time, and evil weirdness ensues.
*/
if ((error = device_power_down(PMSG_FREEZE))) {
+ printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
local_irq_enable();
+ swsusp_free();
return error;
}
save_processor_state();
- error = swsusp_arch_suspend();
+ if ((error = swsusp_arch_suspend()))
+ swsusp_free();
/* Restore control flow magically appears here */
restore_processor_state();
+ BUG_ON (nr_copy_pages_check != nr_copy_pages);
restore_highmem();
device_power_up();
local_irq_enable();
return error;
}
-
-asmlinkage int swsusp_restore(void)
-{
- BUG_ON (nr_copy_pages_check != nr_copy_pages);
- BUG_ON (pagedir_order_check != pagedir_order);
-
- /* Even mappings of "global" things (vmalloc) need to be fixed */
- __flush_tlb_global();
- return 0;
-}
-
int swsusp_resume(void)
{
int error;
local_irq_disable();
- device_power_down(PMSG_FREEZE);
+ if (device_power_down(PMSG_FREEZE))
+ printk(KERN_ERR "Some devices failed to power down, very bad\n");
/* We'll ignore saved state, but this gets preempt count (etc) right */
save_processor_state();
error = swsusp_arch_resume();
/*
* Returns true if given address/order collides with any orig_address
*/
-static int __init does_collide_order(unsigned long addr, int order)
+static int does_collide_order(unsigned long addr, int order)
{
int i;
return 0;
}
-/*
- * We check here that pagedir & pages it points to won't collide with pages
- * where we're going to restore from the loaded pages later
+/**
+ * On resume, for storing the PBE list and the image,
+ * we can only use memory pages that do not conflict with the pages
+ * which had been used before suspend.
+ *
+ * We don't know which pages are usable until we allocate them.
+ *
+ * Allocated but unusable (ie eaten) memory pages are linked together
+ * to create a list, so that we can free them easily
+ *
+ * We could have used a type other than (void *)
+ * for this purpose, but ...
*/
-static int __init check_pagedir(void)
+static void **eaten_memory = NULL;
+
+static inline void eat_page(void *page)
{
- int i;
+ void **c;
- for(i=0; i < nr_copy_pages; i++) {
- unsigned long addr;
+ c = eaten_memory;
+ eaten_memory = page;
+ *eaten_memory = c;
+}
- do {
- addr = get_zeroed_page(GFP_ATOMIC);
- if(!addr)
- return -ENOMEM;
- } while (does_collide_order(addr, 0));
+static unsigned long get_usable_page(unsigned gfp_mask)
+{
+ unsigned long m;
- (pagedir_nosave+i)->address = addr;
+ m = get_zeroed_page(gfp_mask);
+ while (does_collide_order(m, 0)) {
+ eat_page((void *)m);
+ m = get_zeroed_page(gfp_mask);
+ if (!m)
+ break;
}
- return 0;
+ return m;
}
-static int __init swsusp_pagedir_relocate(void)
+static void free_eaten_memory(void)
{
- /*
- * We have to avoid recursion (not to overflow kernel stack),
- * and that's why code looks pretty cryptic
+ unsigned long m;
+ void **c;
+ int i = 0;
+
+ c = eaten_memory;
+ while (c) {
+ m = (unsigned long)c;
+ c = *c;
+ free_page(m);
+ i++;
+ }
+ eaten_memory = NULL;
+ pr_debug("swsusp: %d unused pages freed\n", i);
+}
+
+/**
+ * check_pagedir - We ensure here that pages that the PBEs point to
+ * won't collide with pages where we're going to restore from the loaded
+ * pages later
+ */
+
+static int check_pagedir(struct pbe *pblist)
+{
+ struct pbe *p;
+
+ /* This is necessary, so that we can free allocated pages
+ * in case of failure
*/
- suspend_pagedir_t *old_pagedir = pagedir_nosave;
- void **eaten_memory = NULL;
- void **c = eaten_memory, *m, *f;
- int ret = 0;
+ for_each_pbe (p, pblist)
+ p->address = 0UL;
+
+ for_each_pbe (p, pblist) {
+ p->address = get_usable_page(GFP_ATOMIC);
+ if (!p->address)
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+/**
+ * swsusp_pagedir_relocate - It is possible, that some memory pages
+ * occupied by the list of PBEs collide with pages where we're going to
+ * restore from the loaded pages later. We relocate them here.
+ */
+
+static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist)
+{
struct zone *zone;
- int i;
- struct pbe *p;
unsigned long zone_pfn;
+ struct pbe *pbpage, *tail, *p;
+ void *m;
+ int rel = 0, error = 0;
- printk("Relocating pagedir ");
+ if (!pblist) /* a sanity check */
+ return NULL;
+
+ pr_debug("swsusp: Relocating pagedir (%lu pages to check)\n",
+ swsusp_info.pagedir_pages);
/* Set page flags */
zone->zone_start_pfn));
}
- /* Clear orig address */
+ /* Clear orig addresses */
- for(i = 0, p = pagedir_nosave; i < nr_copy_pages; i++, p++) {
+ for_each_pbe (p, pblist)
ClearPageNosaveFree(virt_to_page(p->orig_address));
- }
- if (!does_collide_order((unsigned long)old_pagedir, pagedir_order)) {
- printk("not necessary\n");
- return check_pagedir();
- }
+ tail = pblist + PB_PAGE_SKIP;
- while ((m = (void *) __get_free_pages(GFP_ATOMIC, pagedir_order)) != NULL) {
- if (!does_collide_order((unsigned long)m, pagedir_order))
- break;
- eaten_memory = m;
- printk( "." );
- *eaten_memory = c;
- c = eaten_memory;
- }
+ /* Relocate colliding pages */
- if (!m) {
- printk("out of memory\n");
- ret = -ENOMEM;
- } else {
- pagedir_nosave =
- memcpy(m, old_pagedir, PAGE_SIZE << pagedir_order);
+ for_each_pb_page (pbpage, pblist) {
+ if (does_collide_order((unsigned long)pbpage, 0)) {
+ m = (void *)get_usable_page(GFP_ATOMIC | __GFP_COLD);
+ if (!m) {
+ error = -ENOMEM;
+ break;
+ }
+ memcpy(m, (void *)pbpage, PAGE_SIZE);
+ if (pbpage == pblist)
+ pblist = (struct pbe *)m;
+ else
+ tail->next = (struct pbe *)m;
+
+ eat_page((void *)pbpage);
+ pbpage = (struct pbe *)m;
+
+ /* We have to link the PBEs again */
+
+ for (p = pbpage; p < pbpage + PB_PAGE_SKIP; p++)
+ if (p->next) /* needed to save the end */
+ p->next = p + 1;
+
+ rel++;
+ }
+ tail = pbpage + PB_PAGE_SKIP;
}
- c = eaten_memory;
- while (c) {
- printk(":");
- f = c;
- c = *c;
- free_pages((unsigned long)f, pagedir_order);
+ if (error) {
+ printk("\nswsusp: Out of memory\n\n");
+ free_pagedir(pblist);
+ free_eaten_memory();
+ pblist = NULL;
}
- if (ret)
- return ret;
- printk("|\n");
- return check_pagedir();
+ else
+ printk("swsusp: Relocated %d pages\n", rel);
+
+ return pblist;
}
-/**
+/*
* Using bio to read from swap.
* This code requires a bit more work than just using buffer heads
* but, it is the recommended way for 2.5/2.6.
* I really don't think that it's foolproof but more than nothing..
*/
-static const char * __init sanity_check(void)
+static const char * sanity_check(void)
{
dump_info();
if(swsusp_info.version_code != LINUX_VERSION_CODE)
}
-static int __init check_header(void)
+static int check_header(void)
{
const char * reason = NULL;
int error;
return -EPERM;
}
nr_copy_pages = swsusp_info.image_pages;
- pagedir_order = get_bitmask_order(SUSPEND_PD_PAGES(nr_copy_pages));
return error;
}
-static int __init check_sig(void)
+static int check_sig(void)
{
int error;
*/
error = bio_write_page(0, &swsusp_header);
} else {
- pr_debug(KERN_ERR "swsusp: Suspend partition has wrong signature?\n");
+ printk(KERN_ERR "swsusp: Suspend partition has wrong signature?\n");
return -EINVAL;
}
if (!error)
}
/**
- * swsusp_read_data - Read image pages from swap.
+ * data_read - Read image pages from swap.
*
* You do not need to check for overlaps, check_pagedir()
* already did that.
*/
-static int __init data_read(void)
+static int data_read(struct pbe *pblist)
{
struct pbe * p;
- int error;
- int i;
- int mod = nr_copy_pages / 100;
+ int error = 0;
+ int i = 0;
+ int mod = swsusp_info.image_pages / 100;
if (!mod)
mod = 1;
- if ((error = swsusp_pagedir_relocate()))
- return error;
+ printk("swsusp: Reading image data (%lu pages): ",
+ swsusp_info.image_pages);
+
+ for_each_pbe (p, pblist) {
+ if (!(i % mod))
+ printk("\b\b\b\b%3d%%", i / mod);
- printk( "Reading image data (%d pages): ", nr_copy_pages );
- for(i = 0, p = pagedir_nosave; i < nr_copy_pages && !error; i++, p++) {
- if (!(i%mod))
- printk( "\b\b\b\b%3d%%", i / mod );
error = bio_read_page(swp_offset(p->swap_address),
(void *)p->address);
+ if (error)
+ return error;
+
+ i++;
}
- printk(" %d done.\n",i);
+ printk("\b\b\b\bdone\n");
return error;
-
}
-extern dev_t __init name_to_dev_t(const char *line);
+extern dev_t name_to_dev_t(const char *line);
-static int __init read_pagedir(void)
+/**
+ * read_pagedir - Read page backup list pages from swap
+ */
+
+static int read_pagedir(struct pbe *pblist)
{
- unsigned long addr;
- int i, n = swsusp_info.pagedir_pages;
- int error = 0;
+ struct pbe *pbpage, *p;
+ unsigned i = 0;
+ int error;
- addr = __get_free_pages(GFP_ATOMIC, pagedir_order);
- if (!addr)
- return -ENOMEM;
- pagedir_nosave = (struct pbe *)addr;
+ if (!pblist)
+ return -EFAULT;
- pr_debug("swsusp: Reading pagedir (%d Pages)\n",n);
+ printk("swsusp: Reading pagedir (%lu pages)\n",
+ swsusp_info.pagedir_pages);
- 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;
+ for_each_pb_page (pbpage, pblist) {
+ unsigned long offset = swp_offset(swsusp_info.pagedir[i++]);
+
+ error = -EFAULT;
+ if (offset) {
+ p = (pbpage + PB_PAGE_SKIP)->next;
+ error = bio_read_page(offset, (void *)pbpage);
+ (pbpage + PB_PAGE_SKIP)->next = p;
+ }
+ if (error)
+ break;
}
+
if (error)
- free_pages((unsigned long)pagedir_nosave, pagedir_order);
+ free_page((unsigned long)pblist);
+
+ BUG_ON(i != swsusp_info.pagedir_pages);
+
return error;
}
-static int __init read_suspend_image(void)
+
+static int check_suspend_image(void)
{
int error = 0;
if ((error = check_sig()))
return error;
+
if ((error = check_header()))
return error;
- if ((error = read_pagedir()))
+
+ return 0;
+}
+
+static int read_suspend_image(void)
+{
+ int error = 0;
+ struct pbe *p;
+
+ if (!(p = alloc_pagedir(nr_copy_pages)))
+ return -ENOMEM;
+
+ if ((error = read_pagedir(p)))
return error;
- if ((error = data_read()))
- free_pages((unsigned long)pagedir_nosave, pagedir_order);
+
+ create_pbe_list(p, nr_copy_pages);
+
+ if (!(pagedir_nosave = swsusp_pagedir_relocate(p)))
+ return -ENOMEM;
+
+ /* Allocate memory for the image and read the data from swap */
+
+ error = check_pagedir(pagedir_nosave);
+ free_eaten_memory();
+ if (!error)
+ error = data_read(pagedir_nosave);
+
+ if (error) { /* We fail cleanly */
+ for_each_pbe (p, pagedir_nosave)
+ if (p->address) {
+ free_page(p->address);
+ p->address = 0UL;
+ }
+ free_pagedir(pagedir_nosave);
+ }
return error;
}
/**
- * swsusp_read - Read saved image from swap.
+ * swsusp_check - Check for saved image in swap
*/
-int __init swsusp_read(void)
+int swsusp_check(void)
{
int error;
- if (!strlen(resume_file))
- return -ENOENT;
-
- resume_device = name_to_dev_t(resume_file);
- pr_debug("swsusp: Resume From Partition: %s\n", resume_file);
+ if (!swsusp_resume_device) {
+ if (!strlen(resume_file))
+ return -ENOENT;
+ swsusp_resume_device = name_to_dev_t(resume_file);
+ pr_debug("swsusp: Resume From Partition %s\n", resume_file);
+ } else {
+ pr_debug("swsusp: Resume From Partition %d:%d\n",
+ MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
+ }
- resume_bdev = open_by_devnum(resume_device, FMODE_READ);
+ resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
if (!IS_ERR(resume_bdev)) {
set_blocksize(resume_bdev, PAGE_SIZE);
- error = read_suspend_image();
- blkdev_put(resume_bdev);
+ error = check_suspend_image();
+ if (error)
+ blkdev_put(resume_bdev);
} else
error = PTR_ERR(resume_bdev);
if (!error)
- pr_debug("Reading resume file was successful\n");
+ pr_debug("swsusp: resume file found\n");
+ else
+ pr_debug("swsusp: Error %d check for resume file\n", error);
+ return error;
+}
+
+/**
+ * swsusp_read - Read saved image from swap.
+ */
+
+int swsusp_read(void)
+{
+ int error;
+
+ if (IS_ERR(resume_bdev)) {
+ pr_debug("swsusp: block device not initialised\n");
+ return PTR_ERR(resume_bdev);
+ }
+
+ error = read_suspend_image();
+ blkdev_put(resume_bdev);
+
+ if (!error)
+ pr_debug("swsusp: Reading resume file was successful\n");
else
pr_debug("swsusp: Error %d resuming\n", error);
return error;
}
+
+/**
+ * swsusp_close - close swap device.
+ */
+
+void swsusp_close(void)
+{
+ if (IS_ERR(resume_bdev)) {
+ pr_debug("swsusp: block device not initialised\n");
+ return;
+ }
+
+ blkdev_put(resume_bdev);
+}
git://git.onelab.eu / linux-2.6.git / blobdiff