shithub: lwext4

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ext4_bcache & ext4_blockdev: unify buffer flushing code.

--- a/lwext4/ext4_bcache.c

+++ b/lwext4/ext4_bcache.c

@@ -36,6 +36,7 @@

 #include "ext4_config.h"

 #include "ext4_bcache.h"

+#include "ext4_blockdev.h"

 #include "ext4_debug.h"

 #include "ext4_errno.h"

@@ -156,10 +157,7 @@

 	/*Forcibly drop dirty buffer.*/

 	if (ext4_bcache_test_flag(buf, BC_DIRTY))

-		SLIST_REMOVE(&bc->dirty_list,

-			     buf,

-			     ext4_buf,

-			     dirty_node);

+		ext4_bcache_remove_dirty_node(bc, buf);

 	ext4_buf_free(buf);

 	bc->ref_blocks--;

@@ -178,10 +176,7 @@

 			buf->lru_id = ++bc->lru_ctr;

 			RB_REMOVE(ext4_buf_lru, &bc->lru_root, buf);

 			if (ext4_bcache_test_flag(buf, BC_DIRTY))

-				SLIST_REMOVE(&bc->dirty_list,

-					     buf,

-					     ext4_buf,

-					     dirty_node);

+				ext4_bcache_remove_dirty_node(bc, buf);

 		}

@@ -255,8 +250,12 @@

 	if (!buf->refctr) {

 		RB_INSERT(ext4_buf_lru, &bc->lru_root, buf);

 		/* This buffer is ready to be flushed. */

-		if (ext4_bcache_test_flag(buf, BC_DIRTY))

-			SLIST_INSERT_HEAD(&bc->dirty_list, buf, dirty_node);

+		if (ext4_bcache_test_flag(buf, BC_DIRTY)) {

+			if (bc->bdev->cache_write_back)

+				ext4_bcache_insert_dirty_node(bc, buf);

+			else

+				ext4_block_flush_buf(bc->bdev, buf);

+		}

 		/* The buffer is invalidated...drop it. */

 		if (!ext4_bcache_test_flag(buf, BC_UPTODATE))

--- a/lwext4/ext4_bcache.h

+++ b/lwext4/ext4_bcache.h

@@ -89,6 +89,9 @@

 	/**@brief   Reference count table*/

 	uint32_t refctr;

+	/**@brief   Whether or not buffer is on dirty list.*/

+	bool on_dirty_list;

+

 	/**@brief   LBA tree node*/

 	RB_ENTRY(ext4_buf) lba_node;

@@ -99,6 +102,27 @@

 	SLIST_ENTRY(ext4_buf) dirty_node;

 };

+#define ext4_bcache_insert_dirty_node(bc, buf) \

+do { \

+	if (!(buf)->on_dirty_list) {             \

+		SLIST_INSERT_HEAD(&(bc)->dirty_list, \

+				  (buf),            \

+				  dirty_node); \

+		(buf)->on_dirty_list = true;  \

+	} \

+} while (0)

+

+#define ext4_bcache_remove_dirty_node(bc, buf) \

+do { \

+	if ((buf)->on_dirty_list) {             \

+		SLIST_REMOVE(&(bc)->dirty_list,  \

+				(buf),           \

+				ext4_buf,      \

+				dirty_node);   \

+		(buf)->on_dirty_list = false;  \

+	} \

+} while (0)

+

 /**@brief   Block cache descriptor*/

 struct ext4_bcache {

@@ -116,6 +140,9 @@

 	/**@brief   Maximum referenced datablocks*/

 	uint32_t max_ref_blocks;

+

+	/**@brief   The blockdev binded to this block cache*/

+	struct ext4_blockdev *bdev;

 	/**@brief   A tree holding all bufs*/

 	RB_HEAD(ext4_buf_lba, ext4_buf) lba_root;

--- a/lwext4/ext4_blockdev.c

+++ b/lwext4/ext4_blockdev.c

@@ -63,6 +63,7 @@

 {

 	ext4_assert(bdev && bc);

 	bdev->bc = bc;

+	bc->bdev = bdev;

 	return EOK;

 }

@@ -85,8 +86,7 @@

 	return bdev->close(bdev);

 }

-static int

-ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf)

+int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf)

 {

 	int r;

 	struct ext4_bcache *bc = bdev->bc;

@@ -98,10 +98,7 @@

 		if (r)

 			return r;

-		SLIST_REMOVE(&bc->dirty_list,

-				buf,

-				ext4_buf,

-				dirty_node);

+		ext4_bcache_remove_dirty_node(bc, buf);

 		ext4_bcache_clear_flag(buf, BC_DIRTY);

 	}

 	return EOK;

@@ -195,10 +192,6 @@

 int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b)

 {

-	uint64_t pba;

-	uint32_t pb_cnt;

-	int r;

-

 	ext4_assert(bdev && b);

 	ext4_assert(b->buf);

@@ -205,37 +198,7 @@

 	if (!(bdev->flags & EXT4_BDEV_INITIALIZED))

 		return EIO;

-	/*Free cache delay mode*/

-	if (bdev->cache_write_back) {

-

-		/*Free cache block and mark as free delayed*/

-		return ext4_bcache_free(bdev->bc, b);

-	}

-

-	if (b->buf->refctr > 1)

-		return ext4_bcache_free(bdev->bc, b);

-

-	/*We handle the dirty flag ourselves.*/

-	if (ext4_bcache_test_flag(b->buf, BC_DIRTY) || b->dirty) {

-		b->uptodate = true;

-		ext4_bcache_set_flag(b->buf, BC_UPTODATE);

-

-		pba = (b->lb_id * bdev->lg_bsize) / bdev->ph_bsize;

-		pb_cnt = bdev->lg_bsize / bdev->ph_bsize;

-

-		r = bdev->bwrite(bdev, b->data, pba, pb_cnt);

-		ext4_bcache_clear_flag(b->buf, BC_DIRTY);

-		if (r != EOK) {

-			b->dirty = true;

-			ext4_bcache_free(bdev->bc, b);

-			return r;

-		}

-

-		b->dirty = false;

-		bdev->bwrite_ctr++;

-	}

-	ext4_bcache_free(bdev->bc, b);

-	return EOK;

+	return ext4_bcache_free(bdev->bc, b);

 }

 int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,

--- a/lwext4/ext4_blockdev.h

+++ b/lwext4/ext4_blockdev.h

@@ -139,6 +139,12 @@

  * @return  standard error code*/

 int ext4_block_fini(struct ext4_blockdev *bdev);

+/**@brief   Flush data in given buffer to disk.

+ * @param   bdev block device descriptor

+ * @param   buf buffer

+ * @return  standard error code*/

+int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf);

+

 /**@brief   Set logical block size in block device.

  * @param   bdev block device descriptor

  * @param   lb_size logical block size (in bytes)