Added block_cache_sync_etc() that allows you to sync single blocks.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20811 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/drivers/fs_cache.h

@@ -1,11 +1,12 @@
-/* File System File and Block Caches
- *
- * Copyright 2004-2005, Haiku Inc. All Rights Reserved.
+/*
+ * Copyright 2004-2007, Haiku Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef _FS_CACHE_H
 #define _FS_CACHE_H
 
+//! File System File and Block Caches
+
 
 #include <fs_interface.h>
 
@@ -37,7 +38,8 @@ extern void block_cache_delete(void *_cache, bool allowWrites);
 extern void *block_cache_create(int fd, off_t numBlocks, size_t blockSize,
 					bool readOnly);
 extern status_t block_cache_sync(void *_cache);
-
+extern status_t block_cache_sync_etc(void *_cache, off_t blockNumber,
+					size_t numBlocks);
 extern status_t block_cache_make_writable(void *_cache, off_t blockNumber,
 					int32 transaction);
 extern void *block_cache_get_writable_etc(void *_cache, off_t blockNumber,

src/add-ons/kernel/file_systems/userlandfs/server/haiku_block_cache.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2004-2006, Axel Dörfler, [email protected]. All rights reserved.
+ * Copyright 2004-2007, Axel Dörfler, [email protected]. All rights reserved.
  * Distributed under the terms of the MIT License.
  */
 
@@ -16,7 +16,7 @@
 #include "haiku_hash.h"
 #include "kernel_emu.h"
 
-// ToDo: this is a naive but growing implementation to test the API:
+// TODO: this is a naive but growing implementation to test the API:
 //	1) block reading/writing is not at all optimized for speed, it will
 //	   just read and write single blocks.
 //	2) the locking could be improved; getting a block should not need to
@@ -1060,6 +1060,39 @@ block_cache_sync(void *_cache)
 }
 
 
+status_t
+block_cache_sync_etc(void *_cache, off_t blockNumber, size_t numBlocks)
+{
+	block_cache *cache = (block_cache *)_cache;
+
+	// we will sync all dirty blocks to disk that have a completed
+	// transaction or no transaction only
+
+	if (blockNumber < 0 || blockNumber >= cache->max_blocks) {
+		panic("block_cache_sync_etc: invalid block number %Ld (max %Ld)",
+			blockNumber, cache->max_blocks - 1);
+		return NULL;
+	}
+
+	BenaphoreLocker locker(&cache->lock);
+
+	for (; numBlocks > 0; numBlocks--, blockNumber++) {
+		cached_block *block = (cached_block *)hash_lookup(cache->hash,
+			&blockNumber);
+		if (block == NULL)
+			continue;
+		if (block->previous_transaction != NULL
+			|| (block->transaction == NULL && block->is_dirty)) {
+			status_t status = write_cached_block(cache, block);
+			if (status != B_OK)
+				return status;
+		}
+	}
+
+	return B_OK;
+}
+
+
 status_t
 block_cache_make_writable(void *_cache, off_t blockNumber, int32 transaction)
 {

src/add-ons/kernel/file_systems/userlandfs/server/haiku_fs_cache.h

@@ -1,11 +1,12 @@
-/* File System File and Block Caches
- *
- * Copyright 2004-2005, Haiku Inc. All Rights Reserved.
+/*
+ * Copyright 2004-2007, Haiku Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef USERLAND_FS_HAIKU_FS_CACHE_H
 #define USERLAND_FS_HAIKU_FS_CACHE_H
 
+//! File System File and Block Caches
+
 
 #include <fs_cache.h>
 
@@ -37,6 +38,8 @@ extern void block_cache_delete(void *_cache, bool allowWrites);
 extern void *block_cache_create(int fd, off_t numBlocks, size_t blockSize,
 					bool readOnly);
 extern status_t block_cache_sync(void *_cache);
+extern status_t block_cache_sync_etc(void *_cache, off_t blockNumber,
+					size_t numBlocks);
 
 extern status_t block_cache_make_writable(void *_cache, off_t blockNumber,
 					int32 transaction);

src/add-ons/kernel/file_systems/userlandfs/server/haiku_kernel_emu.cpp

@@ -265,6 +265,14 @@ block_cache_sync(void *_cache)
 	return UserlandFS::HaikuKernelEmu::block_cache_sync(_cache);
 }
 
+// block_cache_sync_etc
+status_t
+block_cache_sync_etc(void *_cache, off_t blockNumber, size_t numBlocks)
+{
+	return UserlandFS::HaikuKernelEmu::block_cache_sync_etc(_cache,
+		blockNumber, numBlocks);
+}
+
 // block_cache_make_writable
 status_t
 block_cache_make_writable(void *_cache, off_t blockNumber, int32 transaction)

src/system/kernel/cache/block_cache.cpp

@@ -23,7 +23,7 @@
 #include <errno.h>
 
 
-// ToDo: this is a naive but growing implementation to test the API:
+// TODO: this is a naive but growing implementation to test the API:
 //	1) block reading/writing is not at all optimized for speed, it will
 //	   just read and write single blocks.
 //	2) the locking could be improved; getting a block should not need to
@@ -1171,6 +1171,39 @@ block_cache_sync(void *_cache)
 }
 
 
+extern "C" status_t
+block_cache_sync_etc(void *_cache, off_t blockNumber, size_t numBlocks)
+{
+	block_cache *cache = (block_cache *)_cache;
+
+	// we will sync all dirty blocks to disk that have a completed
+	// transaction or no transaction only
+
+	if (blockNumber < 0 || blockNumber >= cache->max_blocks) {
+		panic("block_cache_sync_etc: invalid block number %Ld (max %Ld)",
+			blockNumber, cache->max_blocks - 1);
+		return NULL;
+	}
+
+	BenaphoreLocker locker(&cache->lock);
+
+	for (; numBlocks > 0; numBlocks--, blockNumber++) {
+		cached_block *block = (cached_block *)hash_lookup(cache->hash,
+			&blockNumber);
+		if (block == NULL)
+			continue;
+		if (block->previous_transaction != NULL
+			|| (block->transaction == NULL && block->is_dirty)) {
+			status_t status = write_cached_block(cache, block);
+			if (status != B_OK)
+				return status;
+		}
+	}
+
+	return B_OK;
+}
+
+
 extern "C" status_t
 block_cache_make_writable(void *_cache, off_t blockNumber, int32 transaction)
 {