1 files changed, 46 insertions, 34 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 0b16fb4c06d3..57794a7a435c 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -2621,27 +2621,6 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 	ex_ee_block = le32_to_cpu(ex->ee_block);
 	ex_ee_len = ext4_ext_get_actual_len(ex);
 
-	/*
-	 * If we're starting with an extent other than the last one in the
-	 * node, we need to see if it shares a cluster with the extent to
-	 * the right (towards the end of the file). If its leftmost cluster
-	 * is this extent's rightmost cluster and it is not cluster aligned,
-	 * we'll mark it as a partial that is not to be deallocated.
-	 */
-
-	if (ex != EXT_LAST_EXTENT(eh)) {
-		ext4_fsblk_t current_pblk, right_pblk;
-		long long current_cluster, right_cluster;
-
-		current_pblk = ext4_ext_pblock(ex) + ex_ee_len - 1;
-		current_cluster = (long long)EXT4_B2C(sbi, current_pblk);
-		right_pblk = ext4_ext_pblock(ex + 1);
-		right_cluster = (long long)EXT4_B2C(sbi, right_pblk);
-		if (current_cluster == right_cluster &&
-			EXT4_PBLK_COFF(sbi, right_pblk))
-			*partial_cluster = -right_cluster;
-	}
-
 	trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster);
 
 	while (ex >= EXT_FIRST_EXTENT(eh) &&
@@ -2666,14 +2645,16 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 		if (end < ex_ee_block) {
 			/*
 			 * We're going to skip this extent and move to another,
-			 * so if this extent is not cluster aligned we have
-			 * to mark the current cluster as used to avoid
-			 * accidentally freeing it later on
+			 * so note that its first cluster is in use to avoid
+			 * freeing it when removing blocks.  Eventually, the
+			 * right edge of the truncated/punched region will
+			 * be just to the left.
 			 */
-			pblk = ext4_ext_pblock(ex);
-			if (EXT4_PBLK_COFF(sbi, pblk))
+			if (sbi->s_cluster_ratio > 1) {
+				pblk = ext4_ext_pblock(ex);
 				*partial_cluster =
-					-((long long)EXT4_B2C(sbi, pblk));
+					-(long long) EXT4_B2C(sbi, pblk);
+			}
 			ex--;
 			ex_ee_block = le32_to_cpu(ex->ee_block);
 			ex_ee_len = ext4_ext_get_actual_len(ex);
@@ -2819,7 +2800,7 @@ ext4_ext_more_to_rm(struct ext4_ext_path *path)
 int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
 			  ext4_lblk_t end)
 {
-	struct super_block *sb = inode->i_sb;
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	int depth = ext_depth(inode);
 	struct ext4_ext_path *path = NULL;
 	long long partial_cluster = 0;
@@ -2845,9 +2826,10 @@ again:
 	 */
 	if (end < EXT_MAX_BLOCKS - 1) {
 		struct ext4_extent *ex;
-		ext4_lblk_t ee_block;
+		ext4_lblk_t ee_block, ex_end, lblk;
+		ext4_fsblk_t pblk;
 
-		/* find extent for this block */
+		/* find extent for or closest extent to this block */
 		path = ext4_find_extent(inode, end, NULL, EXT4_EX_NOCACHE);
 		if (IS_ERR(path)) {
 			ext4_journal_stop(handle);
@@ -2867,6 +2849,7 @@ again:
 		}
 
 		ee_block = le32_to_cpu(ex->ee_block);
+		ex_end = ee_block + ext4_ext_get_actual_len(ex) - 1;
 
 		/*
 		 * See if the last block is inside the extent, if so split
@@ -2874,8 +2857,19 @@ again:
 		 * tail of the first part of the split extent in
 		 * ext4_ext_rm_leaf().
 		 */
-		if (end >= ee_block &&
-		    end < ee_block + ext4_ext_get_actual_len(ex) - 1) {
+		if (end >= ee_block && end < ex_end) {
+
+			/*
+			 * If we're going to split the extent, note that
+			 * the cluster containing the block after 'end' is
+			 * in use to avoid freeing it when removing blocks.
+			 */
+			if (sbi->s_cluster_ratio > 1) {
+				pblk = ext4_ext_pblock(ex) + end - ee_block + 2;
+				partial_cluster =
+					-(long long) EXT4_B2C(sbi, pblk);
+			}
+
 			/*
 			 * Split the extent in two so that 'end' is the last
 			 * block in the first new extent. Also we should not
@@ -2886,6 +2880,24 @@ again:
 							 end + 1, 1);
 			if (err < 0)
 				goto out;
+
+		} else if (sbi->s_cluster_ratio > 1 && end >= ex_end) {
+			/*
+			 * If there's an extent to the right its first cluster
+			 * contains the immediate right boundary of the
+			 * truncated/punched region.  Set partial_cluster to
+			 * its negative value so it won't be freed if shared
+			 * with the current extent.  The end < ee_block case
+			 * is handled in ext4_ext_rm_leaf().
+			 */
+			lblk = ex_end + 1;
+			err = ext4_ext_search_right(inode, path, &lblk, &pblk,
+						    &ex);
+			if (err)
+				goto out;
+			if (pblk)
+				partial_cluster =
+					-(long long) EXT4_B2C(sbi, pblk);
 		}
 	}
 	/*
@@ -3003,8 +3015,8 @@ again:
 		int flags = get_default_free_blocks_flags(inode);
 
 		ext4_free_blocks(handle, inode, NULL,
-				 EXT4_C2B(EXT4_SB(sb), partial_cluster),
-				 EXT4_SB(sb)->s_cluster_ratio, flags);
+				 EXT4_C2B(sbi, partial_cluster),
+				 sbi->s_cluster_ratio, flags);
 		partial_cluster = 0;
 	}