target/linux/generic/patches-2.6.34/040-compcache_swap_notify_core_support.patch

   1 --- a/include/linux/blkdev.h
   2 +++ b/include/linux/blkdev.h
   3 @@ -1287,6 +1287,8 @@ struct block_device_operations {
   4                                                 unsigned long long);
   5         int (*revalidate_disk) (struct gendisk *);
   6         int (*getgeo)(struct block_device *, struct hd_geometry *);
   7 +        /* this callback is with swap_lock and sometimes page table lock held */
   8 +        void (*swap_slot_free_notify) (struct block_device *, unsigned long);
   9         struct module *owner;
  10  };
  11
  12 --- a/mm/swapfile.c
  13 +++ b/mm/swapfile.c
  14 @@ -574,6 +574,7 @@ static unsigned char swap_entry_free(str
  15
  16         /* free if no reference */
  17         if (!usage) {
  18 +               struct gendisk *disk = p->bdev->bd_disk;
  19                 if (offset < p->lowest_bit)
  20                         p->lowest_bit = offset;
  21                 if (offset > p->highest_bit)
  22 @@ -583,6 +584,8 @@ static unsigned char swap_entry_free(str
  23                         swap_list.next = p->type;
  24                 nr_swap_pages++;
  25                 p->inuse_pages--;
  26 +               if (disk->fops->swap_slot_free_notify)
  27 +                       disk->fops->swap_slot_free_notify(p->bdev, offset);
  28         }
  29
  30         return usage;