This patch changes the handling of swap partitions by swsusp to avoid
locking of the swap devices that are not used for suspend and, consequently,
simplifies the code.
Signed-off-by: Rafael J. Wysocki <[email protected]>
kernel/power/swsusp.c | 128 ++++++++++++++------------------------------------
1 files changed, 36 insertions(+), 92 deletions(-)
Index: linux-2.6.15-rc5-mm3/kernel/power/swsusp.c
===================================================================
--- linux-2.6.15-rc5-mm3.orig/kernel/power/swsusp.c 2005-12-15 23:00:12.000000000 +0100
+++ linux-2.6.15-rc5-mm3/kernel/power/swsusp.c 2005-12-16 23:15:14.000000000 +0100
@@ -104,13 +104,7 @@ static struct swsusp_info swsusp_info;
* 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 */
-
-static unsigned short swapfile_used[MAX_SWAPFILES];
-static unsigned short root_swap;
+static unsigned short root_swap = 0xffff;
static int mark_swapfiles(swp_entry_t prev)
{
@@ -146,7 +140,7 @@ static int mark_swapfiles(swp_entry_t pr
* devfs, since the resume code can only recognize the form /dev/hda4,
* but the suspend code would see the long name.)
*/
-static int is_resume_device(const struct swap_info_struct *swap_info)
+static inline int is_resume_device(const struct swap_info_struct *swap_info)
{
struct file *file = swap_info->swap_file;
struct inode *inode = file->f_dentry->d_inode;
@@ -157,54 +151,22 @@ static int is_resume_device(const struct
static int swsusp_swap_check(void) /* This is called before saving image */
{
- int i, len;
-
- len=strlen(resume_file);
- root_swap = 0xFFFF;
-
- spin_lock(&swap_lock);
- for (i=0; i<MAX_SWAPFILES; i++) {
- if (!(swap_info[i].flags & SWP_WRITEOK)) {
- swapfile_used[i]=SWAPFILE_UNUSED;
- } else {
- if (!len) {
- printk(KERN_WARNING "resume= option should be used to set suspend device" );
- if (root_swap == 0xFFFF) {
- swapfile_used[i] = SWAPFILE_SUSPEND;
- root_swap = i;
- } else
- swapfile_used[i] = SWAPFILE_IGNORED;
- } else {
- /* we ignore all swap devices that are not the resume_file */
- if (is_resume_device(&swap_info[i])) {
- swapfile_used[i] = SWAPFILE_SUSPEND;
- root_swap = i;
- } else {
- swapfile_used[i] = SWAPFILE_IGNORED;
- }
- }
- }
- }
- spin_unlock(&swap_lock);
- return (root_swap != 0xffff) ? 0 : -ENODEV;
-}
-
-/**
- * This is called after saving image so modification
- * will be lost after resume... and that's what we want.
- * we make the device unusable. A new call to
- * lock_swapdevices can unlock the devices.
- */
-static void lock_swapdevices(void)
-{
int i;
+ if (!swsusp_resume_device)
+ return -ENODEV;
spin_lock(&swap_lock);
- for (i = 0; i< MAX_SWAPFILES; i++)
- if (swapfile_used[i] == SWAPFILE_IGNORED) {
- swap_info[i].flags ^= SWP_WRITEOK;
+ for (i = 0; i < MAX_SWAPFILES; i++) {
+ if (!(swap_info[i].flags & SWP_WRITEOK))
+ continue;
+ if (is_resume_device(swap_info + i)) {
+ spin_unlock(&swap_lock);
+ root_swap = i;
+ return 0;
}
+ }
spin_unlock(&swap_lock);
+ return -ENODEV;
}
/**
@@ -222,19 +184,14 @@ static void lock_swapdevices(void)
static int write_page(unsigned long addr, swp_entry_t *loc)
{
swp_entry_t entry;
- int error = 0;
+ int error = -ENOSPC;
- entry = get_swap_page();
- if (swp_offset(entry) &&
- swapfile_used[swp_type(entry)] == SWAPFILE_SUSPEND) {
- error = rw_swap_page_sync(WRITE, entry,
- virt_to_page(addr));
- if (error == -EIO)
- error = 0;
- if (!error)
+ entry = get_swap_page_of_type(root_swap);
+ if (swp_offset(entry)) {
+ error = rw_swap_page_sync(WRITE, entry, virt_to_page(addr));
+ if (!error || error == -EIO)
*loc = entry;
- } else
- error = -ENOSPC;
+ }
return error;
}
@@ -539,31 +496,38 @@ static int save_image_metadata(struct pb
* enough_swap - Make sure we have enough swap to save the image.
*
* Returns TRUE or FALSE after checking the total amount of swap
- * space avaiable.
- *
- * FIXME: si_swapinfo(&i) returns all swap devices information.
- * We should only consider resume_device.
+ * space avaiable from the resume partition.
*/
static int enough_swap(unsigned int nr_pages)
{
- struct sysinfo i;
+ unsigned int free_swap = swap_info[root_swap].pages -
+ swap_info[root_swap].inuse_pages;
- si_swapinfo(&i);
- pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
- return i.freeswap > (nr_pages + PAGES_FOR_IO +
+ pr_debug("swsusp: free swap pages: %u\n", free_swap);
+ return free_swap > (nr_pages + PAGES_FOR_IO +
(nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
}
/**
- * write_suspend_image - Write entire image and metadata.
+ * swsusp_write - Write entire image and metadata.
+ *
+ * It is important _NOT_ to umount filesystems at this point. We want
+ * them synced (in case something goes wrong) but we DO not want to mark
+ * filesystem clean: it is not. (And it does not matter, if we resume
+ * correctly, we'll mark system clean, anyway.)
*/
-static int write_suspend_image(struct pbe *pblist, unsigned int nr_pages)
+
+int swsusp_write(struct pbe *pblist, unsigned int nr_pages)
{
struct swap_map_page *swap_map;
struct swap_map_handle handle;
int error;
+ if ((error = swsusp_swap_check())) {
+ printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n");
+ return error;
+ }
if (!enough_swap(nr_pages)) {
printk(KERN_ERR "swsusp: Not enough free swap\n");
return -ENOSPC;
@@ -601,26 +565,6 @@ Free_image_entries:
goto Free_swap_map;
}
-/* It is important _NOT_ to umount filesystems at this point. We want
- * them synced (in case something goes wrong) but we DO not want to mark
- * filesystem clean: it is not. (And it does not matter, if we resume
- * correctly, we'll mark system clean, anyway.)
- */
-int swsusp_write(struct pbe *pblist, unsigned int nr_pages)
-{
- int error;
-
- if ((error = swsusp_swap_check())) {
- printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n");
- return error;
- }
- lock_swapdevices();
- error = write_suspend_image(pblist, nr_pages);
- /* This will unlock ignored swap devices since writing is finished */
- lock_swapdevices();
- return error;
-}
-
/**
* swsusp_shrink_memory - Try to free as much memory as needed
*
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
