Handle notification on page eviction

If requested by the user, make libpager call pager_notify_evict when a page
is flushed out by the kernel. Based on work by Ognyan Kulev.

* console/pager.c (pager_notify_evict): New function.
(user_pager_create): Update call to pager_create.
* ext2fs/pager.c: (pager_notify_evict): New function.
(create_disk_pager): Update call to diskfs_start_disk_pager.
(diskfs_get_filemap): Update call to pager_create.
* fatfs/pager.c: (pager_notify_evict): New function.
(create_fat_pager): Update call to diskfs_start_disk_pager.
(diskfs_get_filemap): Update call to pager_create.
* isofs/pager.c: (pager_notify_evict): New function.
(create_disk_pager): Update call to diskfs_start_disk_pager.
(diskfs_get_filemap): Update call to pager_create.
* libdiskfs/disk-pager.c (diskfs_start_disk_pager): Update definition and call
to pager_create.
* libdiskfs/diskfs-pager.h (diskfs_start_disk_pager): Update declaration.
* libpager/data-request.c (_pager_seqnos_memory_object_data_request): Take
pager's `notify_on_evict' member into account when calling
memory_object_data_supply.
* libpager/data-return.c (_pager_do_write_request): Handle user notification
on page flush.
* libpager/pager-create.c (pager_create): Update definition and set pager's
`notify_on_evict' member.
* libpager/pager.h (pager_create): Update declaration.
(pager_notify_evict): New declaration.
* libpager/priv.h (struct pager): New `notify_on_evict' member.
* storeio/pager.c: (pager_notify_evict): New function.
(dev_get_memory_object): Update call to pager_create.
* tmpfs/pager-stubs.c (pager_notify_evict): New function.
* ufs/pager.c (pager_notify_evict): New function.
(create_disk_pager): Update call to diskfs_start_disk_pager.
(diskfs_get_filemap): Update call to pager_create.

1 files changed, 10 insertions, 2 deletions

diff --git a/isofs/pager.c b/isofs/pager.c
index f93e0c82..7a38ba33 100644
--- a/isofs/pager.c
+++ b/isofs/pager.c
@@ -94,6 +94,13 @@ pager_unlock_page (struct user_pager_info *pager,
   return EROFS;
 }
 
+void
+pager_notify_evict (struct user_pager_info *pager,
+		    vm_offset_t page)
+{
+  assert (!"unrequested notification on eviction");
+}
+
 /* Tell how big the file is. */
 error_t
 pager_report_extent (struct user_pager_info *pager,
@@ -137,7 +144,7 @@ create_disk_pager (void)
   upi->type = DISK;
   upi->np = 0;
   pager_bucket = ports_create_bucket ();
-  diskfs_start_disk_pager (upi, pager_bucket, 1, store->size, &disk_image);
+  diskfs_start_disk_pager (upi, pager_bucket, 1, 0, store->size, &disk_image);
   upi->p = diskfs_disk_pager;
 }
 
@@ -168,7 +175,8 @@ diskfs_get_filemap (struct node *np, vm_prot_t prot)
 	upi->type = FILE_DATA;
 	upi->np = np;
 	diskfs_nref_light (np);
-	upi->p = pager_create (upi, pager_bucket, 1, MEMORY_OBJECT_COPY_DELAY);
+	upi->p = pager_create (upi, pager_bucket, 1,
+			       MEMORY_OBJECT_COPY_DELAY, 0);
 	if (upi->p == 0)
 	  {
 	    diskfs_nrele_light (np);