Large store support for ext2fs

This is a revised version of the large store patch for ext2fs, written
by Ognyan Kulev. It provides support for stores larger than 2 GiB.

* ext2fs/balloc.c: Use the new disk_cache_block_ref and disk_cache_block_deref
functions to access blocks from the disk cache.
* ext2fs/ext2fs.c (main): Update initialization call to pokel_init, and
call map_hypermetadata instead of get_hypermetadata.
* ext2fs/ext2fs.h: Include <hurd/store.h> and <hurd/ihash.h>.
(DISK_CACHE_BLOCKS): New macro.
(DC_INCORE): Likewise.
(DC_UNTOUCHED): Likewise.
(DC_FIXED): Likewise.
(DC_DONT_REUSE): Likewise.
(DC_NO_BLOCK): Likewise.
(DISK_CACHE_LAST_READ_XOR) [!NDEBUG]: Likewise.
(struct disk_cache_info): New structure.
(disk_cache): New external variable.
(disk_cache_size): Likewise.
(disk_cache_blocks): Likewise.
(disk_cache_bptr): Likewise.
(disk_cache_info): Likewise.
(disk_cache_lock): Likewise.
(disk_cache_reassociation): Likewise.
(disk_cache_block_ref): New declaration.
(disk_cache_block_ref_ptr): Likewise.
(disk_cache_block_deref): Likewise.
(disk_cache_block_is_ref): Likewise.
(map_hypermetadata): Likewise.
(trunc_block): Cast to off_t.
(round_block): Likewise.
(boffs): Likewise.
(bptr_index): New macro.
(boffs_ptr): Rewrite as an inline function to make it look up a block from
the disk cache.
(bptr_offs): Likewise.
(dino): Remove function, replaced with ...
(dino_ref): ... this one, which adds a reference to the inode block.
(dino_deref): New inline function.
(record_global_poke): Make sure block is referenced.
(record_indir_poke): Likewise.
(sync_global_ptr): Remove block reference, and adjust call to
pager_sync_some.
(sync_global): Add debug call to print wait parameter.
* ext2fs/getblk.c: Use the new disk_cache_block_ref and disk_cache_block_deref
functions to access blocks from the disk cache.
* ext2fs/hyper.c (get_hypermetadata): Read the superblock from the store
now that it's not directly mapped in memory. Move the initialization of
zeroblock here from ...
(map_hypermetadata): ... here. Also, set the superblock pointer.
(diskfs_set_hypermetadata): Add a reference to the superblock.
(diskfs_readonly_changed): Update call to mprotect.
* ext2fs/ialloc.c: Use the new disk_cache_block_ref, disk_cache_block_ref_ptr
and disk_cache_block_deref functions to access blocks from the disk cache.
* ext2fs/inode.c: Update calls that used the disk image to use the disk cache,
and use the new reference handling functions where appropriate.
* ext2fs/pager.c: Include <unistd.h> and "../libpager/priv.h".
(disk_image): Remove global variable.
(disk_pager_read_page): Update cache information.
(disk_pager_write_page): Likewise.
(disk_pager_notify_evict): New function.
(pager_notify_evict): Call disk_pager_notify_evict appropriately.
(disk_cache): New global variable.
(disk_cache_size): Likewise.
(disk_cache_blocks): Likewise.
(disk_cache_bptr): Likewise.
(disk_cache_info): Likewise.
(disk_cache_hint): Likewise.
(disk_cache_lock): Likewise.
(disk_cache_reassociation): Likewise.
(disk_cache_init): New function.
(disk_cache_return_unused): Likewise.
(disk_cache_block_ref): Likewise.
(disk_cache_block_ref_ptr): Likewise.
(disk_cache_block_deref): Likewise.
(disk_cache_block_is_ref): Likewise.
(create_disk_pager): Update initialization of the disk pager.
* ext2fs/pokel.c (pokel_add): Drop block references with disk_cache_block_deref.
(_pokel_exec): Likewise.
* ext2fs/truncate.c (trunc_indirect): Use the new disk_cache_block_ref and
disk_cache_block_deref functions to access blocks from the disk cache.

1 files changed, 32 insertions, 7 deletions

diff --git a/ext2fs/pokel.c b/ext2fs/pokel.c
index a8b16c97..3afb32e4 100644
--- a/ext2fs/pokel.c
+++ b/ext2fs/pokel.c
@@ -67,12 +67,27 @@ pokel_add (struct pokel *pokel, void *loc, vm_size_t length)
       vm_offset_t p_offs = pl->offset;
       vm_size_t p_end = p_offs + pl->length;
 
-      if (p_offs == offset && p_end == end)
-	break;
+      if (p_offs <= offset && end <= p_end)
+	{
+	  if (pokel->image == disk_cache)
+	    for (vm_offset_t i = offset; i < end; i += block_size)
+	      disk_cache_block_deref (disk_cache + i);
+
+	  break;
+	}
       else if (p_end >= offset && end >= p_offs)
 	{
 	  pl->offset = offset < p_offs ? offset : p_offs;
 	  pl->length = (end > p_end ? end : p_end) - pl->offset;
+
+	  if (pokel->image == disk_cache)
+	    {
+	      vm_offset_t i_begin = p_offs > offset ? p_offs : offset;
+	      vm_offset_t i_end = p_end < end ? p_end : end;
+	      for (vm_offset_t i = i_begin; i < i_end; i += block_size)
+		disk_cache_block_deref (disk_cache + i);
+	    }
+
 	  ext2_debug ("extended 0x%x[%ul] to 0x%x[%ul]",
 		      p_offs, p_end - p_offs, pl->offset, pl->length);
 	  break;
@@ -113,11 +128,21 @@ _pokel_exec (struct pokel *pokel, int sync, int wait)
   pthread_spin_unlock (&pokel->lock);
 
   for (pl = pokes; pl; last = pl, pl = pl->next)
-    if (sync)
-      {
-	ext2_debug ("syncing 0x%x[%ul]", pl->offset, pl->length);
-	pager_sync_some (pokel->pager, pl->offset, pl->length, wait);
-      }
+    {
+      if (sync)
+	{
+	  ext2_debug ("syncing 0x%lx[%ul]", pl->offset, pl->length);
+	  pager_sync_some (pokel->pager, pl->offset, pl->length, wait);
+	}
+
+      if (pokel->image == disk_cache)
+	{
+	  vm_offset_t begin = trunc_block (pl->offset);
+	  vm_offset_t end = round_block (pl->offset + pl->length);
+	  for (vm_offset_t i = begin; i != end; i += block_size)
+	    disk_cache_block_deref (pokel->image + i);
+	}
+    }
 
   if (last)
     {