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, 11 insertions, 3 deletions

diff --git a/ext2fs/pager.c b/ext2fs/pager.c
index f740434a..92137112 100644
--- a/ext2fs/pager.c
+++ b/ext2fs/pager.c
@@ -511,6 +511,13 @@ pager_write_page (struct user_pager_info *pager, vm_offset_t page,
   else
     return file_pager_write_page (pager->node, page, (void *)buf);
 }
+
+void
+pager_notify_evict (struct user_pager_info *pager, vm_offset_t page)
+{
+  assert (!"unrequested notification on eviction");
+}
+
 
 /* Make page PAGE writable, at least up to ALLOCSIZE.  This function and
    diskfs_grow are the only places that blocks are actually added to the
@@ -776,8 +783,9 @@ create_disk_pager (void)
     ext2_panic ("can't create disk pager: %s", strerror (errno));
   upi->type = DISK;
   pager_bucket = ports_create_bucket ();
-  diskfs_start_disk_pager (upi, pager_bucket, MAY_CACHE, store->size,
-			   &disk_image);
+  diskfs_start_disk_pager (upi, pager_bucket, MAY_CACHE, 0,
+			   store->size, &disk_image);
+
 }
 
 /* Call this to create a FILE_DATA pager and return a send right.
@@ -817,7 +825,7 @@ diskfs_get_filemap (struct node *node, vm_prot_t prot)
 	  diskfs_nref_light (node);
 	  node->dn->pager =
 	    pager_create (upi, pager_bucket, MAY_CACHE,
-			  MEMORY_OBJECT_COPY_DELAY);
+			  MEMORY_OBJECT_COPY_DELAY, 0);
 	  if (node->dn->pager == 0)
 	    {
 	      diskfs_nrele_light (node);