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))