1 files changed, 193 insertions, 77 deletions

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index fcfb10f771202..34e5b0dc9168b 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -235,16 +235,6 @@ no_delete:
 	clear_inode(inode);	/* We must guarantee clearing of inode... */
 }
 
-static int ext3_alloc_block (handle_t *handle,
-			struct inode * inode, unsigned long goal, int *err)
-{
-	unsigned long result;
-
-	result = ext3_new_block(handle, inode, goal, err);
-	return result;
-}
-
-
 typedef struct {
 	__le32	*p;
 	__le32	key;
@@ -476,15 +466,115 @@ static unsigned long ext3_find_goal(struct inode *inode, long block,
 
 	return ext3_find_near(inode, partial);
 }
+/**
+ *	ext3_blks_to_allocate: Look up the block map and count the number
+ *	of direct blocks need to be allocated for the given branch.
+ *
+ * 	@branch: chain of indirect blocks
+ *	@k: number of blocks need for indirect blocks
+ *	@blks: number of data blocks to be mapped.
+ *	@blocks_to_boundary:  the offset in the indirect block
+ *
+ *	return the total number of blocks to be allocate, including the
+ *	direct and indirect blocks.
+ */
+static int
+ext3_blks_to_allocate(Indirect * branch, int k, unsigned long blks,
+		int blocks_to_boundary)
+{
+	unsigned long count = 0;
+
+	/*
+	 * Simple case, [t,d]Indirect block(s) has not allocated yet
+	 * then it's clear blocks on that path have not allocated
+	 */
+	if (k > 0) {
+		/* right now don't hanel cross boundary allocation */
+		if (blks < blocks_to_boundary + 1)
+			count += blks;
+		else
+			count += blocks_to_boundary + 1;
+		return count;
+	}
+
+	count++;
+	while (count < blks && count <= blocks_to_boundary &&
+		le32_to_cpu(*(branch[0].p + count)) == 0) {
+		count++;
+	}
+	return count;
+}
+
+/**
+ *	ext3_alloc_blocks: multiple allocate blocks needed for a branch
+ *	@indirect_blks: the number of blocks need to allocate for indirect
+ *			blocks
+ *
+ *	@new_blocks: on return it will store the new block numbers for
+ *	the indirect blocks(if needed) and the first direct block,
+ *	@blks:	on return it will store the total number of allocated
+ *		direct blocks
+ */
+static int ext3_alloc_blocks(handle_t *handle, struct inode *inode,
+			unsigned long goal, int indirect_blks, int blks,
+			unsigned long long new_blocks[4], int *err)
+{
+	int target, i;
+	unsigned long count = 0;
+	int index = 0;
+	unsigned long current_block = 0;
+	int ret = 0;
+
+	/*
+	 * Here we try to allocate the requested multiple blocks at once,
+	 * on a best-effort basis.
+	 * To build a branch, we should allocate blocks for
+	 * the indirect blocks(if not allocated yet), and at least
+	 * the first direct block of this branch.  That's the
+	 * minimum number of blocks need to allocate(required)
+	 */
+	target = blks + indirect_blks;
+
+	while (1) {
+		count = target;
+		/* allocating blocks for indirect blocks and direct blocks */
+		current_block = ext3_new_blocks(handle, inode, goal, &count, err);
+		if (*err)
+			goto failed_out;
+
+		target -= count;
+		/* allocate blocks for indirect blocks */
+		while (index < indirect_blks && count) {
+			new_blocks[index++] = current_block++;
+			count--;
+		}
+
+		if (count > 0)
+			break;
+	}
+
+	/* save the new block number for the first direct block */
+	new_blocks[index] = current_block;
+
+	/* total number of blocks allocated for direct blocks */
+	ret = count;
+	*err = 0;
+	return ret;
+failed_out:
+	for (i = 0; i <index; i++)
+		ext3_free_blocks(handle, inode, new_blocks[i], 1);
+	return ret;
+}
 
 /**
  *	ext3_alloc_branch - allocate and set up a chain of blocks.
  *	@inode: owner
- *	@num: depth of the chain (number of blocks to allocate)
+ *	@indirect_blks: number of allocated indirect blocks
+ *	@blks: number of allocated direct blocks
  *	@offsets: offsets (in the blocks) to store the pointers to next.
  *	@branch: place to store the chain in.
  *
- *	This function allocates @num blocks, zeroes out all but the last one,
+ *	This function allocates blocks, zeroes out all but the last one,
  *	links them into chain and (if we are synchronous) writes them to disk.
  *	In other words, it prepares a branch that can be spliced onto the
  *	inode. It stores the information about that chain in the branch[], in
@@ -503,71 +593,79 @@ static unsigned long ext3_find_goal(struct inode *inode, long block,
  */
 
 static int ext3_alloc_branch(handle_t *handle, struct inode *inode,
-			     int num,
-			     unsigned long goal,
-			     int *offsets,
-			     Indirect *branch)
+			int indirect_blks, int *blks, unsigned long goal,
+			int *offsets, Indirect *branch)
 {
 	int blocksize = inode->i_sb->s_blocksize;
-	int n = 0, keys = 0;
+	int i, n = 0;
 	int err = 0;
-	int i;
-	int parent = ext3_alloc_block(handle, inode, goal, &err);
-
-	branch[0].key = cpu_to_le32(parent);
-	if (parent) {
-		for (n = 1; n < num; n++) {
-			struct buffer_head *bh;
-			/* Allocate the next block */
-			int nr = ext3_alloc_block(handle, inode, parent, &err);
-			if (!nr)
-				break;
-			branch[n].key = cpu_to_le32(nr);
+	struct buffer_head *bh;
+	int num;
+	unsigned long long new_blocks[4];
+	unsigned long long current_block;
 
-			/*
-			 * Get buffer_head for parent block, zero it out
-			 * and set the pointer to new one, then send
-			 * parent to disk.  
-			 */
-			bh = sb_getblk(inode->i_sb, parent);
-			if (!bh)
-				break;
-			keys = n+1;
-			branch[n].bh = bh;
-			lock_buffer(bh);
-			BUFFER_TRACE(bh, "call get_create_access");
-			err = ext3_journal_get_create_access(handle, bh);
-			if (err) {
-				unlock_buffer(bh);
-				brelse(bh);
-				break;
-			}
+	num = ext3_alloc_blocks(handle, inode, goal, indirect_blks,
+				*blks, new_blocks, &err);
+	if (err)
+		return err;
 
-			memset(bh->b_data, 0, blocksize);
-			branch[n].p = (__le32*) bh->b_data + offsets[n];
-			*branch[n].p = branch[n].key;
-			BUFFER_TRACE(bh, "marking uptodate");
-			set_buffer_uptodate(bh);
+	branch[0].key = cpu_to_le32(new_blocks[0]);
+	/*
+	 * metadata blocks and data blocks are allocated.
+	 */
+	for (n = 1; n <= indirect_blks;  n++) {
+		/*
+		 * Get buffer_head for parent block, zero it out
+		 * and set the pointer to new one, then send
+		 * parent to disk.
+		 */
+		bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
+		branch[n].bh = bh;
+		lock_buffer(bh);
+		BUFFER_TRACE(bh, "call get_create_access");
+		err = ext3_journal_get_create_access(handle, bh);
+		if (err) {
 			unlock_buffer(bh);
+			brelse(bh);
+			goto failed;
+		}
 
-			BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
-			err = ext3_journal_dirty_metadata(handle, bh);
-			if (err)
-				break;
-
-			parent = nr;
+		memset(bh->b_data, 0, blocksize);
+		branch[n].p = (__le32 *) bh->b_data + offsets[n];
+		branch[n].key = cpu_to_le32(new_blocks[n]);
+		*branch[n].p = branch[n].key;
+		if ( n == indirect_blks) {
+			current_block = new_blocks[n];
+			/*
+			 * End of chain, update the last new metablock of
+			 * the chain to point to the new allocated
+			 * data blocks numbers
+			 */
+			for (i=1; i < num; i++)
+				*(branch[n].p + i) = cpu_to_le32(++current_block);
 		}
-	}
-	if (n == num)
-		return 0;
+		BUFFER_TRACE(bh, "marking uptodate");
+		set_buffer_uptodate(bh);
+		unlock_buffer(bh);
 
+		BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
+		err = ext3_journal_dirty_metadata(handle, bh);
+		if (err)
+			goto failed;
+	}
+	*blks = num;
+	return err;
+failed:
 	/* Allocation failed, free what we already allocated */
-	for (i = 1; i < keys; i++) {
+	for (i = 1; i <= n ; i++) {
 		BUFFER_TRACE(branch[i].bh, "call journal_forget");
 		ext3_journal_forget(handle, branch[i].bh);
 	}
-	for (i = 0; i < keys; i++)
-		ext3_free_blocks(handle, inode, le32_to_cpu(branch[i].key), 1);
+	for (i = 0; i <indirect_blks; i++)
+		ext3_free_blocks(handle, inode, new_blocks[i], 1);
+
+	ext3_free_blocks(handle, inode, new_blocks[i], num);
+
 	return err;
 }
 
@@ -578,7 +676,8 @@ static int ext3_alloc_branch(handle_t *handle, struct inode *inode,
  *	@chain: chain of indirect blocks (with a missing link - see
  *		ext3_alloc_branch)
  *	@where: location of missing link
- *	@num:   number of blocks we are adding
+ *	@num:   number of indirect blocks we are adding
+ *	@blks:  number of direct blocks we are adding
  *
  *	This function fills the missing link and does all housekeeping needed in
  *	inode (->i_blocks, etc.). In case of success we end up with the full
@@ -586,12 +685,12 @@ static int ext3_alloc_branch(handle_t *handle, struct inode *inode,
  */
 
 static int ext3_splice_branch(handle_t *handle, struct inode *inode, long block,
-			      Indirect chain[4], Indirect *where, int num)
+			      Indirect *where, int num, int blks)
 {
 	int i;
 	int err = 0;
 	struct ext3_block_alloc_info *block_i = EXT3_I(inode)->i_block_alloc_info;
-
+	unsigned long current_block;
 	/*
 	 * If we're splicing into a [td]indirect block (as opposed to the
 	 * inode) then we need to get write access to the [td]indirect block
@@ -606,6 +705,13 @@ static int ext3_splice_branch(handle_t *handle, struct inode *inode, long block,
 	/* That's it */
 
 	*where->p = where->key;
+	/* update host bufferhead or inode to point to
+	 * more just allocated direct blocks blocks */
+	if (num == 0 && blks > 1) {
+		current_block = le32_to_cpu(where->key + 1);
+		for (i = 1; i < blks; i++)
+			*(where->p + i ) = cpu_to_le32(current_block++);
+	}
 
 	/*
 	 * update the most recently allocated logical & physical block
@@ -613,8 +719,8 @@ static int ext3_splice_branch(handle_t *handle, struct inode *inode, long block,
 	 * allocation
 	 */
 	if (block_i) {
-		block_i->last_alloc_logical_block = block;
-		block_i->last_alloc_physical_block = le32_to_cpu(where[num-1].key);
+		block_i->last_alloc_logical_block = block + blks - 1;
+		block_i->last_alloc_physical_block = le32_to_cpu(where[num].key + blks - 1);
 	}
 
 	/* We are done with atomic stuff, now do the rest of housekeeping */
@@ -647,10 +753,13 @@ static int ext3_splice_branch(handle_t *handle, struct inode *inode, long block,
 	return err;
 
 err_out:
-	for (i = 1; i < num; i++) {
+	for (i = 1; i <= num; i++) {
 		BUFFER_TRACE(where[i].bh, "call journal_forget");
 		ext3_journal_forget(handle, where[i].bh);
+		ext3_free_blocks(handle, inode, le32_to_cpu(where[i-1].key), 1);
 	}
+	ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks);
+
 	return err;
 }
 
@@ -684,7 +793,7 @@ ext3_get_blocks_handle(handle_t *handle, struct inode *inode, sector_t iblock,
 	Indirect chain[4];
 	Indirect *partial;
 	unsigned long goal;
-	int left;
+	int indirect_blks;
 	int blocks_to_boundary = 0;
 	int depth;
 	struct ext3_inode_info *ei = EXT3_I(inode);
@@ -772,12 +881,19 @@ ext3_get_blocks_handle(handle_t *handle, struct inode *inode, sector_t iblock,
 
 	goal = ext3_find_goal(inode, iblock, chain, partial);
 
-	left = (chain + depth) - partial;
+	/* the number of blocks need to allocate for [d,t]indirect blocks */
+	indirect_blks = (chain + depth) - partial - 1;
 
 	/*
+	 * Next look up the indirect map to count the totoal number of
+	 * direct blocks to allocate for this branch.
+	 */
+	count = ext3_blks_to_allocate(partial, indirect_blks,
+					maxblocks, blocks_to_boundary);
+	/*
 	 * Block out ext3_truncate while we alter the tree
 	 */
-	err = ext3_alloc_branch(handle, inode, left, goal,
+	err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal,
 				offsets + (partial - chain), partial);
 
 	/*
@@ -788,8 +904,8 @@ ext3_get_blocks_handle(handle_t *handle, struct inode *inode, sector_t iblock,
 	 * may need to return -EAGAIN upwards in the worst case.  --sct
 	 */
 	if (!err)
-		err = ext3_splice_branch(handle, inode, iblock, chain,
-					 partial, left);
+		err = ext3_splice_branch(handle, inode, iblock,
+					partial, indirect_blks, count);
 	/*
 	 * i_disksize growing is protected by truncate_mutex.  Don't forget to
 	 * protect it if you're about to implement concurrent
@@ -824,8 +940,8 @@ out:
 
 static int
 ext3_direct_io_get_blocks(struct inode *inode, sector_t iblock,
-		unsigned long max_blocks, struct buffer_head *bh_result,
-		int create)
+		unsigned long max_blocks,
+		struct buffer_head *bh_result, int create)
 {
 	handle_t *handle = journal_current_handle();
 	int ret = 0;