Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "Fix a regression when trying to compile ext4 on older versions gcc.

  Fix a number of miscellaneous bugs for punch hole as well as a
  long-standing potential double buffer head release when failing a
  block allocation for an indirect-mapped file"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Fix hole punching for files with indirect blocks
  ext4: Fix block zeroing when punching holes in indirect block files
  ext4: decrement free clusters/inodes counters when block group declared bad
  fs/mbcache: replace __builtin_log2() with ilog2()
  ext4: Fix buffer double free in ext4_alloc_branch()

5 files changed, 68 insertions, 6 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 0762d143e252..fca382037ddd 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -194,7 +194,16 @@ static void ext4_init_block_bitmap(struct super_block *sb,
 	if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
 		ext4_error(sb, "Checksum bad for group %u", block_group);
 		grp = ext4_get_group_info(sb, block_group);
+		if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
+			percpu_counter_sub(&sbi->s_freeclusters_counter,
+					   grp->bb_free);
 		set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
+		if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
+			int count;
+			count = ext4_free_inodes_count(sb, gdp);
+			percpu_counter_sub(&sbi->s_freeinodes_counter,
+					   count);
+		}
 		set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
 		return;
 	}
@@ -359,6 +368,7 @@ static void ext4_validate_block_bitmap(struct super_block *sb,
 {
 	ext4_fsblk_t	blk;
 	struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
 	if (buffer_verified(bh))
 		return;
@@ -369,6 +379,9 @@ static void ext4_validate_block_bitmap(struct super_block *sb,
 		ext4_unlock_group(sb, block_group);
 		ext4_error(sb, "bg %u: block %llu: invalid block bitmap",
 			   block_group, blk);
+		if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
+			percpu_counter_sub(&sbi->s_freeclusters_counter,
+					   grp->bb_free);
 		set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
 		return;
 	}
@@ -376,6 +389,9 @@ static void ext4_validate_block_bitmap(struct super_block *sb,
 			desc, bh))) {
 		ext4_unlock_group(sb, block_group);
 		ext4_error(sb, "bg %u: bad block bitmap checksum", block_group);
+		if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
+			percpu_counter_sub(&sbi->s_freeclusters_counter,
+					   grp->bb_free);
 		set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
 		return;
 	}
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 0ee59a6644e2..a87455df38bc 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -71,6 +71,7 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb,
 				       struct ext4_group_desc *gdp)
 {
 	struct ext4_group_info *grp;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	J_ASSERT_BH(bh, buffer_locked(bh));
 
 	/* If checksum is bad mark all blocks and inodes use to prevent
@@ -78,7 +79,16 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb,
 	if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
 		ext4_error(sb, "Checksum bad for group %u", block_group);
 		grp = ext4_get_group_info(sb, block_group);
+		if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
+			percpu_counter_sub(&sbi->s_freeclusters_counter,
+					   grp->bb_free);
 		set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
+		if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
+			int count;
+			count = ext4_free_inodes_count(sb, gdp);
+			percpu_counter_sub(&sbi->s_freeinodes_counter,
+					   count);
+		}
 		set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
 		return 0;
 	}
@@ -116,6 +126,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
 	struct buffer_head *bh = NULL;
 	ext4_fsblk_t bitmap_blk;
 	struct ext4_group_info *grp;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
 	desc = ext4_get_group_desc(sb, block_group, NULL);
 	if (!desc)
@@ -185,6 +196,12 @@ verify:
 		ext4_error(sb, "Corrupt inode bitmap - block_group = %u, "
 			   "inode_bitmap = %llu", block_group, bitmap_blk);
 		grp = ext4_get_group_info(sb, block_group);
+		if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
+			int count;
+			count = ext4_free_inodes_count(sb, desc);
+			percpu_counter_sub(&sbi->s_freeinodes_counter,
+					   count);
+		}
 		set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
 		return NULL;
 	}
@@ -321,6 +338,12 @@ out:
 			fatal = err;
 	} else {
 		ext4_error(sb, "bit already cleared for inode %lu", ino);
+		if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
+			int count;
+			count = ext4_free_inodes_count(sb, gdp);
+			percpu_counter_sub(&sbi->s_freeinodes_counter,
+					   count);
+		}
 		set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
 	}
 
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 8a57e9fcd1b9..fd69da194826 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -389,7 +389,13 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 	return 0;
 failed:
 	for (; i >= 0; i--) {
-		if (i != indirect_blks && branch[i].bh)
+		/*
+		 * We want to ext4_forget() only freshly allocated indirect
+		 * blocks.  Buffer for new_blocks[i-1] is at branch[i].bh and
+		 * buffer at branch[0].bh is indirect block / inode already
+		 * existing before ext4_alloc_branch() was called.
+		 */
+		if (i > 0 && 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],
@@ -1310,16 +1316,24 @@ static int free_hole_blocks(handle_t *handle, struct inode *inode,
 		blk = *i_data;
 		if (level > 0) {
 			ext4_lblk_t first2;
+			ext4_lblk_t count2;
+
 			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;
+			if (first > offset) {
+				first2 = first - offset;
+				count2 = count;
+			} else {
+				first2 = 0;
+				count2 = count - (offset - first);
+			}
 			ret = free_hole_blocks(handle, inode, bh,
 					       (__le32 *)bh->b_data, level - 1,
-					       first2, count - offset,
+					       first2, count2,
 					       inode->i_sb->s_blocksize >> 2);
 			if (ret) {
 				brelse(bh);
@@ -1329,8 +1343,8 @@ static int free_hole_blocks(handle_t *handle, struct inode *inode,
 		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;
+			ext4_free_data(handle, inode, parent_bh,
+				       i_data, i_data + 1);
 		}
 		brelse(bh);
 		bh = NULL;
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 59e31622cc6e..7f72f50a8fa7 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -722,6 +722,7 @@ void ext4_mb_generate_buddy(struct super_block *sb,
 				void *buddy, void *bitmap, ext4_group_t group)
 {
 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	ext4_grpblk_t max = EXT4_CLUSTERS_PER_GROUP(sb);
 	ext4_grpblk_t i = 0;
 	ext4_grpblk_t first;
@@ -759,6 +760,9 @@ void ext4_mb_generate_buddy(struct super_block *sb,
 		 * corrupt and update bb_free using bitmap value
 		 */
 		grp->bb_free = free;
+		if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
+			percpu_counter_sub(&sbi->s_freeclusters_counter,
+					   grp->bb_free);
 		set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
 	}
 	mb_set_largest_free_order(sb, grp);
@@ -1431,6 +1435,7 @@ static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
 		right_is_free = !mb_test_bit(last + 1, e4b->bd_bitmap);
 
 	if (unlikely(block != -1)) {
+		struct ext4_sb_info *sbi = EXT4_SB(sb);
 		ext4_fsblk_t blocknr;
 
 		blocknr = ext4_group_first_block_no(sb, e4b->bd_group);
@@ -1441,6 +1446,9 @@ static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
 				      "freeing already freed block "
 				      "(bit %u); block bitmap corrupt.",
 				      block);
+		if (!EXT4_MB_GRP_BBITMAP_CORRUPT(e4b->bd_info))
+			percpu_counter_sub(&sbi->s_freeclusters_counter,
+					   e4b->bd_info->bb_free);
 		/* Mark the block group as corrupt. */
 		set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 			&e4b->bd_info->bb_state);
diff --git a/fs/mbcache.c b/fs/mbcache.c
index bf166e388f0d..187477ded6b3 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -73,6 +73,7 @@
 #include <linux/mbcache.h>
 #include <linux/init.h>
 #include <linux/blockgroup_lock.h>
+#include <linux/log2.h>
 
 #ifdef MB_CACHE_DEBUG
 # define mb_debug(f...) do { \
@@ -93,7 +94,7 @@
 
 #define MB_CACHE_WRITER ((unsigned short)~0U >> 1)
 
-#define MB_CACHE_ENTRY_LOCK_BITS	__builtin_log2(NR_BG_LOCKS)
+#define MB_CACHE_ENTRY_LOCK_BITS	ilog2(NR_BG_LOCKS)
 #define	MB_CACHE_ENTRY_LOCK_INDEX(ce)			\
 	(hash_long((unsigned long)ce, MB_CACHE_ENTRY_LOCK_BITS))