1 files changed, 156 insertions, 293 deletions

diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 20862f96e8a..87b30cd357e 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -20,6 +20,7 @@
  *	(sct@redhat.com), 1993, 1998
  */
 
+#include <linux/aio.h>
 #include "ext4_jbd2.h"
 #include "truncate.h"
 #include "ext4_extents.h"	/* Needed for EXT_MAX_BLOCKS */
@@ -146,6 +147,7 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
 	struct super_block *sb = inode->i_sb;
 	Indirect *p = chain;
 	struct buffer_head *bh;
+	int ret = -EIO;
 
 	*err = 0;
 	/* i_data is not going away, no lock needed */
@@ -154,8 +156,10 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
 		goto no_block;
 	while (--depth) {
 		bh = sb_getblk(sb, le32_to_cpu(p->key));
-		if (unlikely(!bh))
+		if (unlikely(!bh)) {
+			ret = -ENOMEM;
 			goto failure;
+		}
 
 		if (!bh_uptodate_or_lock(bh)) {
 			if (bh_submit_read(bh) < 0) {
@@ -177,7 +181,7 @@ static Indirect *ext4_get_branch(struct inode *inode, int depth,
 	return NULL;
 
 failure:
-	*err = -EIO;
+	*err = ret;
 no_block:
 	return p;
 }
@@ -289,132 +293,6 @@ static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks,
 }
 
 /**
- *	ext4_alloc_blocks: multiple allocate blocks needed for a branch
- *	@handle: handle for this transaction
- *	@inode: inode which needs allocated blocks
- *	@iblock: the logical block to start allocated at
- *	@goal: preferred physical block of allocation
- *	@indirect_blks: the number of blocks need to allocate for indirect
- *			blocks
- *	@blks: number of desired blocks
- *	@new_blocks: on return it will store the new block numbers for
- *	the indirect blocks(if needed) and the first direct block,
- *	@err: on return it will store the error code
- *
- *	This function will return the number of blocks allocated as
- *	requested by the passed-in parameters.
- */
-static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
-			     ext4_lblk_t iblock, ext4_fsblk_t goal,
-			     int indirect_blks, int blks,
-			     ext4_fsblk_t new_blocks[4], int *err)
-{
-	struct ext4_allocation_request ar;
-	int target, i;
-	unsigned long count = 0, blk_allocated = 0;
-	int index = 0;
-	ext4_fsblk_t 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)
-	 */
-	/* first we try to allocate the indirect blocks */
-	target = indirect_blks;
-	while (target > 0) {
-		count = target;
-		/* allocating blocks for indirect blocks and direct blocks */
-		current_block = ext4_new_meta_blocks(handle, inode, goal,
-						     0, &count, err);
-		if (*err)
-			goto failed_out;
-
-		if (unlikely(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS)) {
-			EXT4_ERROR_INODE(inode,
-					 "current_block %llu + count %lu > %d!",
-					 current_block, count,
-					 EXT4_MAX_BLOCK_FILE_PHYS);
-			*err = -EIO;
-			goto failed_out;
-		}
-
-		target -= count;
-		/* allocate blocks for indirect blocks */
-		while (index < indirect_blks && count) {
-			new_blocks[index++] = current_block++;
-			count--;
-		}
-		if (count > 0) {
-			/*
-			 * save the new block number
-			 * for the first direct block
-			 */
-			new_blocks[index] = current_block;
-			printk(KERN_INFO "%s returned more blocks than "
-						"requested\n", __func__);
-			WARN_ON(1);
-			break;
-		}
-	}
-
-	target = blks - count ;
-	blk_allocated = count;
-	if (!target)
-		goto allocated;
-	/* Now allocate data blocks */
-	memset(&ar, 0, sizeof(ar));
-	ar.inode = inode;
-	ar.goal = goal;
-	ar.len = target;
-	ar.logical = iblock;
-	if (S_ISREG(inode->i_mode))
-		/* enable in-core preallocation only for regular files */
-		ar.flags = EXT4_MB_HINT_DATA;
-
-	current_block = ext4_mb_new_blocks(handle, &ar, err);
-	if (unlikely(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS)) {
-		EXT4_ERROR_INODE(inode,
-				 "current_block %llu + ar.len %d > %d!",
-				 current_block, ar.len,
-				 EXT4_MAX_BLOCK_FILE_PHYS);
-		*err = -EIO;
-		goto failed_out;
-	}
-
-	if (*err && (target == blks)) {
-		/*
-		 * if the allocation failed and we didn't allocate
-		 * any blocks before
-		 */
-		goto failed_out;
-	}
-	if (!*err) {
-		if (target == blks) {
-			/*
-			 * save the new block number
-			 * for the first direct block
-			 */
-			new_blocks[index] = current_block;
-		}
-		blk_allocated += ar.len;
-	}
-allocated:
-	/* total number of blocks allocated for direct blocks */
-	ret = blk_allocated;
-	*err = 0;
-	return ret;
-failed_out:
-	for (i = 0; i < index; i++)
-		ext4_free_blocks(handle, inode, NULL, new_blocks[i], 1, 0);
-	return ret;
-}
-
-/**
  *	ext4_alloc_branch - allocate and set up a chain of blocks.
  *	@handle: handle for this transaction
  *	@inode: owner
@@ -446,60 +324,59 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 			     int *blks, ext4_fsblk_t goal,
 			     ext4_lblk_t *offsets, Indirect *branch)
 {
-	int blocksize = inode->i_sb->s_blocksize;
-	int i, n = 0;
-	int err = 0;
-	struct buffer_head *bh;
-	int num;
-	ext4_fsblk_t new_blocks[4];
-	ext4_fsblk_t current_block;
-
-	num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks,
-				*blks, new_blocks, &err);
-	if (err)
-		return err;
+	struct ext4_allocation_request	ar;
+	struct buffer_head *		bh;
+	ext4_fsblk_t			b, new_blocks[4];
+	__le32				*p;
+	int				i, j, err, len = 1;
 
-	branch[0].key = cpu_to_le32(new_blocks[0]);
 	/*
-	 * metadata blocks and data blocks are allocated.
+	 * Set up for the direct block allocation
 	 */
-	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]);
-		if (unlikely(!bh)) {
-			err = -EIO;
+	memset(&ar, 0, sizeof(ar));
+	ar.inode = inode;
+	ar.len = *blks;
+	ar.logical = iblock;
+	if (S_ISREG(inode->i_mode))
+		ar.flags = EXT4_MB_HINT_DATA;
+
+	for (i = 0; i <= indirect_blks; i++) {
+		if (i == indirect_blks) {
+			ar.goal = goal;
+			new_blocks[i] = ext4_mb_new_blocks(handle, &ar, &err);
+		} else
+			goal = new_blocks[i] = ext4_new_meta_blocks(handle, inode,
+							goal, 0, NULL, &err);
+		if (err) {
+			i--;
 			goto failed;
 		}
+		branch[i].key = cpu_to_le32(new_blocks[i]);
+		if (i == 0)
+			continue;
 
-		branch[n].bh = bh;
+		bh = branch[i].bh = sb_getblk(inode->i_sb, new_blocks[i-1]);
+		if (unlikely(!bh)) {
+			err = -ENOMEM;
+			goto failed;
+		}
 		lock_buffer(bh);
 		BUFFER_TRACE(bh, "call get_create_access");
 		err = ext4_journal_get_create_access(handle, bh);
 		if (err) {
-			/* Don't brelse(bh) here; it's done in
-			 * ext4_journal_forget() below */
 			unlock_buffer(bh);
 			goto failed;
 		}
 
-		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);
-		}
+		memset(bh->b_data, 0, bh->b_size);
+		p = branch[i].p = (__le32 *) bh->b_data + offsets[i];
+		b = new_blocks[i];
+
+		if (i == indirect_blks)
+			len = ar.len;
+		for (j = 0; j < len; j++)
+			*p++ = cpu_to_le32(b++);
+
 		BUFFER_TRACE(bh, "marking uptodate");
 		set_buffer_uptodate(bh);
 		unlock_buffer(bh);
@@ -509,25 +386,16 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 		if (err)
 			goto failed;
 	}
-	*blks = num;
-	return err;
+	*blks = ar.len;
+	return 0;
 failed:
-	/* Allocation failed, free what we already allocated */
-	ext4_free_blocks(handle, inode, NULL, new_blocks[0], 1, 0);
-	for (i = 1; i <= n ; i++) {
-		/*
-		 * branch[i].bh is newly allocated, so there is no
-		 * need to revoke the block, which is why we don't
-		 * need to set EXT4_FREE_BLOCKS_METADATA.
-		 */
-		ext4_free_blocks(handle, inode, NULL, new_blocks[i], 1,
-				 EXT4_FREE_BLOCKS_FORGET);
+	for (; i >= 0; i--) {
+		if (i != indirect_blks && branch[i].bh)
+			ext4_forget(handle, 1, inode, branch[i].bh,
+				    branch[i].bh->b_blocknr);
+		ext4_free_blocks(handle, inode, NULL, new_blocks[i],
+				 (i == indirect_blks) ? ar.len : 1, 0);
 	}
-	for (i = n+1; i < indirect_blks; i++)
-		ext4_free_blocks(handle, inode, NULL, new_blocks[i], 1, 0);
-
-	ext4_free_blocks(handle, inode, NULL, new_blocks[i], num, 0);
-
 	return err;
 }
 
@@ -756,7 +624,7 @@ cleanup:
 		partial--;
 	}
 out:
-	trace_ext4_ind_map_blocks_exit(inode, map, err);
+	trace_ext4_ind_map_blocks_exit(inode, flags, map, err);
 	return err;
 }
 
@@ -789,7 +657,7 @@ ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
 
 		if (final_size > inode->i_size) {
 			/* Credits for sb + inode write */
-			handle = ext4_journal_start(inode, 2);
+			handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
 			if (IS_ERR(handle)) {
 				ret = PTR_ERR(handle);
 				goto out;
@@ -807,11 +675,6 @@ ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
 
 retry:
 	if (rw == READ && ext4_should_dioread_nolock(inode)) {
-		if (unlikely(atomic_read(&EXT4_I(inode)->i_unwritten))) {
-			mutex_lock(&inode->i_mutex);
-			ext4_flush_unwritten_io(inode);
-			mutex_unlock(&inode->i_mutex);
-		}
 		/*
 		 * Nolock dioread optimization may be dynamically disabled
 		 * via ext4_inode_block_unlocked_dio(). Check inode's state
@@ -849,7 +712,7 @@ locked:
 		int err;
 
 		/* Credits for sb + inode write */
-		handle = ext4_journal_start(inode, 2);
+		handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
 		if (IS_ERR(handle)) {
 			/* This is really bad luck. We've written the data
 			 * but cannot extend i_size. Bail out and pretend
@@ -911,27 +774,18 @@ int ext4_ind_calc_metadata_amount(struct inode *inode, sector_t lblock)
 	return (blk_bits / EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb)) + 1;
 }
 
-int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk)
+/*
+ * Calculate number of indirect blocks touched by mapping @nrblocks logically
+ * contiguous blocks
+ */
+int ext4_ind_trans_blocks(struct inode *inode, int nrblocks)
 {
-	int indirects;
-
-	/* if nrblocks are contiguous */
-	if (chunk) {
-		/*
-		 * With N contiguous data blocks, we need at most
-		 * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) + 1 indirect blocks,
-		 * 2 dindirect blocks, and 1 tindirect block
-		 */
-		return DIV_ROUND_UP(nrblocks,
-				    EXT4_ADDR_PER_BLOCK(inode->i_sb)) + 4;
-	}
 	/*
-	 * if nrblocks are not contiguous, worse case, each block touch
-	 * a indirect block, and each indirect block touch a double indirect
-	 * block, plus a triple indirect block
+	 * With N contiguous data blocks, we need at most
+	 * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) + 1 indirect blocks,
+	 * 2 dindirect blocks, and 1 tindirect block
 	 */
-	indirects = nrblocks * 2 + 1;
-	return indirects;
+	return DIV_ROUND_UP(nrblocks, EXT4_ADDR_PER_BLOCK(inode->i_sb)) + 4;
 }
 
 /*
@@ -939,25 +793,9 @@ int ext4_ind_trans_blocks(struct inode *inode, int nrblocks, int chunk)
  * be able to restart the transaction at a conventient checkpoint to make
  * sure we don't overflow the journal.
  *
- * start_transaction gets us a new handle for a truncate transaction,
- * and extend_transaction tries to extend the existing one a bit.  If
+ * Try to extend this transaction for the purposes of truncation.  If
  * extend fails, we need to propagate the failure up and restart the
  * transaction in the top-level truncate loop. --sct
- */
-static handle_t *start_transaction(struct inode *inode)
-{
-	handle_t *result;
-
-	result = ext4_journal_start(inode, ext4_blocks_for_truncate(inode));
-	if (!IS_ERR(result))
-		return result;
-
-	ext4_std_error(inode->i_sb, PTR_ERR(result));
-	return result;
-}
-
-/*
- * Try to extend this transaction for the purposes of truncation.
  *
  * Returns 0 if we managed to create more room.  If we can't create more
  * room, and the transaction must be restarted we return 1.
@@ -1088,11 +926,13 @@ static int ext4_clear_blocks(handle_t *handle, struct inode *inode,
 			     __le32 *last)
 {
 	__le32 *p;
-	int	flags = EXT4_FREE_BLOCKS_FORGET | EXT4_FREE_BLOCKS_VALIDATED;
+	int	flags = EXT4_FREE_BLOCKS_VALIDATED;
 	int	err;
 
 	if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
-		flags |= EXT4_FREE_BLOCKS_METADATA;
+		flags |= EXT4_FREE_BLOCKS_FORGET | EXT4_FREE_BLOCKS_METADATA;
+	else if (ext4_should_journal_data(inode))
+		flags |= EXT4_FREE_BLOCKS_FORGET;
 
 	if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), block_to_free,
 				   count)) {
@@ -1350,68 +1190,30 @@ static void ext4_free_branches(handle_t *handle, struct inode *inode,
 	}
 }
 
-void ext4_ind_truncate(struct inode *inode)
+void ext4_ind_truncate(handle_t *handle, struct inode *inode)
 {
-	handle_t *handle;
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	__le32 *i_data = ei->i_data;
 	int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
-	struct address_space *mapping = inode->i_mapping;
 	ext4_lblk_t offsets[4];
 	Indirect chain[4];
 	Indirect *partial;
 	__le32 nr = 0;
 	int n = 0;
 	ext4_lblk_t last_block, max_block;
-	loff_t page_len;
 	unsigned blocksize = inode->i_sb->s_blocksize;
-	int err;
-
-	handle = start_transaction(inode);
-	if (IS_ERR(handle))
-		return;		/* AKPM: return what? */
 
 	last_block = (inode->i_size + blocksize-1)
 					>> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
 	max_block = (EXT4_SB(inode->i_sb)->s_bitmap_maxbytes + blocksize-1)
 					>> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
 
-	if (inode->i_size % PAGE_CACHE_SIZE != 0) {
-		page_len = PAGE_CACHE_SIZE -
-			(inode->i_size & (PAGE_CACHE_SIZE - 1));
-
-		err = ext4_discard_partial_page_buffers(handle,
-			mapping, inode->i_size, page_len, 0);
-
-		if (err)
-			goto out_stop;
-	}
-
 	if (last_block != max_block) {
 		n = ext4_block_to_path(inode, last_block, offsets, NULL);
 		if (n == 0)
-			goto out_stop;	/* error */
+			return;
 	}
 
-	/*
-	 * OK.  This truncate is going to happen.  We add the inode to the
-	 * orphan list, so that if this truncate spans multiple transactions,
-	 * and we crash, we will resume the truncate when the filesystem
-	 * recovers.  It also marks the inode dirty, to catch the new size.
-	 *
-	 * Implication: the file must always be in a sane, consistent
-	 * truncatable state while each transaction commits.
-	 */
-	if (ext4_orphan_add(handle, inode))
-		goto out_stop;
-
-	/*
-	 * From here we block out all ext4_get_block() callers who want to
-	 * modify the block allocation tree.
-	 */
-	down_write(&ei->i_data_sem);
-
-	ext4_discard_preallocations(inode);
 	ext4_es_remove_extent(inode, last_block, EXT_MAX_BLOCKS - last_block);
 
 	/*
@@ -1428,7 +1230,7 @@ void ext4_ind_truncate(struct inode *inode)
 		 * It is unnecessary to free any data blocks if last_block is
 		 * equal to the indirect block limit.
 		 */
-		goto out_unlock;
+		return;
 	} else if (n == 1) {		/* direct blocks */
 		ext4_free_data(handle, inode, NULL, i_data+offsets[0],
 			       i_data + EXT4_NDIR_BLOCKS);
@@ -1488,30 +1290,91 @@ do_indirects:
 	case EXT4_TIND_BLOCK:
 		;
 	}
+}
 
-out_unlock:
-	up_write(&ei->i_data_sem);
-	inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
-	ext4_mark_inode_dirty(handle, inode);
+static int free_hole_blocks(handle_t *handle, struct inode *inode,
+			    struct buffer_head *parent_bh, __le32 *i_data,
+			    int level, ext4_lblk_t first,
+			    ext4_lblk_t count, int max)
+{
+	struct buffer_head *bh = NULL;
+	int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+	int ret = 0;
+	int i, inc;
+	ext4_lblk_t offset;
+	__le32 blk;
 
-	/*
-	 * In a multi-transaction truncate, we only make the final transaction
-	 * synchronous
-	 */
-	if (IS_SYNC(inode))
-		ext4_handle_sync(handle);
-out_stop:
-	/*
-	 * If this was a simple ftruncate(), and the file will remain alive
-	 * then we need to clear up the orphan record which we created above.
-	 * However, if this was a real unlink then we were called by
-	 * ext4_delete_inode(), and we allow that function to clean up the
-	 * orphan info for us.
-	 */
-	if (inode->i_nlink)
-		ext4_orphan_del(handle, inode);
+	inc = 1 << ((EXT4_BLOCK_SIZE_BITS(inode->i_sb) - 2) * level);
+	for (i = 0, offset = 0; i < max; i++, i_data++, offset += inc) {
+		if (offset >= count + first)
+			break;
+		if (*i_data == 0 || (offset + inc) <= first)
+			continue;
+		blk = *i_data;
+		if (level > 0) {
+			ext4_lblk_t first2;
+			bh = sb_bread(inode->i_sb, le32_to_cpu(blk));
+			if (!bh) {
+				EXT4_ERROR_INODE_BLOCK(inode, le32_to_cpu(blk),
+						       "Read failure");
+				return -EIO;
+			}
+			first2 = (first > offset) ? first - offset : 0;
+			ret = free_hole_blocks(handle, inode, bh,
+					       (__le32 *)bh->b_data, level - 1,
+					       first2, count - offset,
+					       inode->i_sb->s_blocksize >> 2);
+			if (ret) {
+				brelse(bh);
+				goto err;
+			}
+		}
+		if (level == 0 ||
+		    (bh && all_zeroes((__le32 *)bh->b_data,
+				      (__le32 *)bh->b_data + addr_per_block))) {
+			ext4_free_data(handle, inode, parent_bh, &blk, &blk+1);
+			*i_data = 0;
+		}
+		brelse(bh);
+		bh = NULL;
+	}
+
+err:
+	return ret;
+}
+
+int ext4_free_hole_blocks(handle_t *handle, struct inode *inode,
+			  ext4_lblk_t first, ext4_lblk_t stop)
+{
+	int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+	int level, ret = 0;
+	int num = EXT4_NDIR_BLOCKS;
+	ext4_lblk_t count, max = EXT4_NDIR_BLOCKS;
+	__le32 *i_data = EXT4_I(inode)->i_data;
+
+	count = stop - first;
+	for (level = 0; level < 4; level++, max *= addr_per_block) {
+		if (first < max) {
+			ret = free_hole_blocks(handle, inode, NULL, i_data,
+					       level, first, count, num);
+			if (ret)
+				goto err;
+			if (count > max - first)
+				count -= max - first;
+			else
+				break;
+			first = 0;
+		} else {
+			first -= max;
+		}
+		i_data += num;
+		if (level == 0) {
+			num = 1;
+			max = 1;
+		}
+	}
 
-	ext4_journal_stop(handle);
-	trace_ext4_truncate_exit(inode);
+err:
+	return ret;
 }