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Diffstat (limited to 'mm/swapfile.c')
-rw-r--r--mm/swapfile.c38
1 files changed, 26 insertions, 12 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c
index f315131db00..2bfacbac0f4 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -427,34 +427,48 @@ void free_swap_and_cache(swp_entry_t entry)
#ifdef CONFIG_SOFTWARE_SUSPEND
/*
- * Find the swap type that corresponds to given device (if any)
+ * Find the swap type that corresponds to given device (if any).
*
- * This is needed for software suspend and is done in such a way that inode
- * aliasing is allowed.
+ * @offset - number of the PAGE_SIZE-sized block of the device, starting
+ * from 0, in which the swap header is expected to be located.
+ *
+ * This is needed for the suspend to disk (aka swsusp).
*/
-int swap_type_of(dev_t device)
+int swap_type_of(dev_t device, sector_t offset)
{
+ struct block_device *bdev = NULL;
int i;
+ if (device)
+ bdev = bdget(device);
+
spin_lock(&swap_lock);
for (i = 0; i < nr_swapfiles; i++) {
- struct inode *inode;
+ struct swap_info_struct *sis = swap_info + i;
- if (!(swap_info[i].flags & SWP_WRITEOK))
+ if (!(sis->flags & SWP_WRITEOK))
continue;
- if (!device) {
+ if (!bdev) {
spin_unlock(&swap_lock);
return i;
}
- inode = swap_info[i].swap_file->f_dentry->d_inode;
- if (S_ISBLK(inode->i_mode) &&
- device == MKDEV(imajor(inode), iminor(inode))) {
- spin_unlock(&swap_lock);
- return i;
+ if (bdev == sis->bdev) {
+ struct swap_extent *se;
+
+ se = list_entry(sis->extent_list.next,
+ struct swap_extent, list);
+ if (se->start_block == offset) {
+ spin_unlock(&swap_lock);
+ bdput(bdev);
+ return i;
+ }
}
}
spin_unlock(&swap_lock);
+ if (bdev)
+ bdput(bdev);
+
return -ENODEV;
}