1 files changed, 317 insertions, 134 deletions

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index c9900aade150..8d141a25bbee 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -381,22 +381,28 @@ static inline void mb_clear_bit_atomic(spinlock_t *lock, int bit, void *addr)
 
 static inline int mb_find_next_zero_bit(void *addr, int max, int start)
 {
-        int fix = 0;
+        int fix = 0, ret, tmpmax;
         addr = mb_correct_addr_and_bit(&fix, addr);
-        max += fix;
+        tmpmax = max + fix;
         start += fix;
 
-        return ext4_find_next_zero_bit(addr, max, start) - fix;
+        ret = ext4_find_next_zero_bit(addr, tmpmax, start) - fix;
+        if (ret > max)
+                return max;
+        return ret;
 }
 
 static inline int mb_find_next_bit(void *addr, int max, int start)
 {
-        int fix = 0;
+        int fix = 0, ret, tmpmax;
         addr = mb_correct_addr_and_bit(&fix, addr);
-        max += fix;
+        tmpmax = max + fix;
         start += fix;
 
-        return ext4_find_next_bit(addr, max, start) - fix;
+        ret = ext4_find_next_bit(addr, tmpmax, start) - fix;
+        if (ret > max)
+                return max;
+        return ret;
 }
 
 static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max)
@@ -803,6 +809,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore)
                 if (!buffer_uptodate(bh[i]))
                         goto out;
 
+        err = 0;
         first_block = page->index * blocks_per_page;
         for (i = 0; i < blocks_per_page; i++) {
                 int group;
@@ -883,6 +890,7 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
         int pnum;
         int poff;
         struct page *page;
+        int ret;
 
         mb_debug("load group %lu\n", group);
 
@@ -914,15 +922,21 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
                 if (page) {
                         BUG_ON(page->mapping != inode->i_mapping);
                         if (!PageUptodate(page)) {
-                                ext4_mb_init_cache(page, NULL);
+                                ret = ext4_mb_init_cache(page, NULL);
+                                if (ret) {
+                                        unlock_page(page);
+                                        goto err;
+                                }
                                 mb_cmp_bitmaps(e4b, page_address(page) +
                                                (poff * sb->s_blocksize));
                         }
                         unlock_page(page);
                 }
         }
-        if (page == NULL || !PageUptodate(page))
+        if (page == NULL || !PageUptodate(page)) {
+                ret = -EIO;
                 goto err;
+        }
         e4b->bd_bitmap_page = page;
         e4b->bd_bitmap = page_address(page) + (poff * sb->s_blocksize);
         mark_page_accessed(page);
@@ -938,14 +952,20 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
                 page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
                 if (page) {
                         BUG_ON(page->mapping != inode->i_mapping);
-                        if (!PageUptodate(page))
-                                ext4_mb_init_cache(page, e4b->bd_bitmap);
-
+                        if (!PageUptodate(page)) {
+                                ret = ext4_mb_init_cache(page, e4b->bd_bitmap);
+                                if (ret) {
+                                        unlock_page(page);
+                                        goto err;
+                                }
+                        }
                         unlock_page(page);
                 }
         }
-        if (page == NULL || !PageUptodate(page))
+        if (page == NULL || !PageUptodate(page)) {
+                ret = -EIO;
                 goto err;
+        }
         e4b->bd_buddy_page = page;
         e4b->bd_buddy = page_address(page) + (poff * sb->s_blocksize);
         mark_page_accessed(page);
@@ -962,7 +982,7 @@ err:
                 page_cache_release(e4b->bd_buddy_page);
         e4b->bd_buddy = NULL;
         e4b->bd_bitmap = NULL;
-        return -EIO;
+        return ret;
 }
 
 static void ext4_mb_release_desc(struct ext4_buddy *e4b)
@@ -1031,7 +1051,7 @@ static void mb_set_bits(spinlock_t *lock, void *bm, int cur, int len)
         }
 }
 
-static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
+static void mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
                           int first, int count)
 {
         int block = 0;
@@ -1071,11 +1091,12 @@ static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
                         blocknr += block;
                         blocknr +=
                             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
-
+                        ext4_unlock_group(sb, e4b->bd_group);
                         ext4_error(sb, __func__, "double-free of inode"
                                    " %lu's block %llu(bit %u in group %lu)\n",
                                    inode ? inode->i_ino : 0, blocknr, block,
                                    e4b->bd_group);
+                        ext4_lock_group(sb, e4b->bd_group);
                 }
                 mb_clear_bit(block, EXT4_MB_BITMAP(e4b));
                 e4b->bd_info->bb_counters[order]++;
@@ -1113,8 +1134,6 @@ static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b,
                 } while (1);
         }
         mb_check_buddy(e4b);
-
-        return 0;
 }
 
 static int mb_find_extent(struct ext4_buddy *e4b, int order, int block,
@@ -1730,10 +1749,6 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
                 ac->ac_g_ex.fe_start = sbi->s_mb_last_start;
                 spin_unlock(&sbi->s_md_lock);
         }
-
-        /* searching for the right group start from the goal value specified */
-        group = ac->ac_g_ex.fe_group;
-
         /* Let's just scan groups to find more-less suitable blocks */
         cr = ac->ac_2order ? 0 : 1;
         /*
@@ -1743,6 +1758,12 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
 repeat:
         for (; cr < 4 && ac->ac_status == AC_STATUS_CONTINUE; cr++) {
                 ac->ac_criteria = cr;
+                /*
+                 * searching for the right group start
+                 * from the goal value specified
+                 */
+                group = ac->ac_g_ex.fe_group;
+
                 for (i = 0; i < EXT4_SB(sb)->s_groups_count; group++, i++) {
                         struct ext4_group_info *grp;
                         struct ext4_group_desc *desc;
@@ -1963,6 +1984,8 @@ static int ext4_mb_seq_history_open(struct inode *inode, struct file *file)
         int rc;
         int size;
 
+        if (unlikely(sbi->s_mb_history == NULL))
+                return -ENOMEM;
         s = kmalloc(sizeof(*s), GFP_KERNEL);
         if (s == NULL)
                 return -ENOMEM;
@@ -2165,9 +2188,7 @@ static void ext4_mb_history_init(struct super_block *sb)
         sbi->s_mb_history_cur = 0;
         spin_lock_init(&sbi->s_mb_history_lock);
         i = sbi->s_mb_history_max * sizeof(struct ext4_mb_history);
-        sbi->s_mb_history = kmalloc(i, GFP_KERNEL);
-        if (likely(sbi->s_mb_history != NULL))
-                memset(sbi->s_mb_history, 0, i);
+        sbi->s_mb_history = kzalloc(i, GFP_KERNEL);
         /* if we can't allocate history, then we simple won't use it */
 }
 
@@ -2215,21 +2236,192 @@ ext4_mb_store_history(struct ext4_allocation_context *ac)
 #define ext4_mb_history_init(sb)
 #endif
 
+
+/* Create and initialize ext4_group_info data for the given group. */
+int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group,
+                          struct ext4_group_desc *desc)
+{
+        int i, len;
+        int metalen = 0;
+        struct ext4_sb_info *sbi = EXT4_SB(sb);
+        struct ext4_group_info **meta_group_info;
+
+        /*
+         * First check if this group is the first of a reserved block.
+         * If it's true, we have to allocate a new table of pointers
+         * to ext4_group_info structures
+         */
+        if (group % EXT4_DESC_PER_BLOCK(sb) == 0) {
+                metalen = sizeof(*meta_group_info) <<
+                        EXT4_DESC_PER_BLOCK_BITS(sb);
+                meta_group_info = kmalloc(metalen, GFP_KERNEL);
+                if (meta_group_info == NULL) {
+                        printk(KERN_ERR "EXT4-fs: can't allocate mem for a "
+                               "buddy group\n");
+                        goto exit_meta_group_info;
+                }
+                sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)] =
+                        meta_group_info;
+        }
+
+        /*
+         * calculate needed size. if change bb_counters size,
+         * don't forget about ext4_mb_generate_buddy()
+         */
+        len = offsetof(typeof(**meta_group_info),
+                       bb_counters[sb->s_blocksize_bits + 2]);
+
+        meta_group_info =
+                sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)];
+        i = group & (EXT4_DESC_PER_BLOCK(sb) - 1);
+
+        meta_group_info[i] = kzalloc(len, GFP_KERNEL);
+        if (meta_group_info[i] == NULL) {
+                printk(KERN_ERR "EXT4-fs: can't allocate buddy mem\n");
+                goto exit_group_info;
+        }
+        set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT,
+                &(meta_group_info[i]->bb_state));
+
+        /*
+         * initialize bb_free to be able to skip
+         * empty groups without initialization
+         */
+        if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
+                meta_group_info[i]->bb_free =
+                        ext4_free_blocks_after_init(sb, group, desc);
+        } else {
+                meta_group_info[i]->bb_free =
+                        le16_to_cpu(desc->bg_free_blocks_count);
+        }
+
+        INIT_LIST_HEAD(&meta_group_info[i]->bb_prealloc_list);
+
+#ifdef DOUBLE_CHECK
+        {
+                struct buffer_head *bh;
+                meta_group_info[i]->bb_bitmap =
+                        kmalloc(sb->s_blocksize, GFP_KERNEL);
+                BUG_ON(meta_group_info[i]->bb_bitmap == NULL);
+                bh = ext4_read_block_bitmap(sb, group);
+                BUG_ON(bh == NULL);
+                memcpy(meta_group_info[i]->bb_bitmap, bh->b_data,
+                        sb->s_blocksize);
+                put_bh(bh);
+        }
+#endif
+
+        return 0;
+
+exit_group_info:
+        /* If a meta_group_info table has been allocated, release it now */
+        if (group % EXT4_DESC_PER_BLOCK(sb) == 0)
+                kfree(sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)]);
+exit_meta_group_info:
+        return -ENOMEM;
+} /* ext4_mb_add_groupinfo */
+
+/*
+ * Add a group to the existing groups.
+ * This function is used for online resize
+ */
+int ext4_mb_add_more_groupinfo(struct super_block *sb, ext4_group_t group,
+                               struct ext4_group_desc *desc)
+{
+        struct ext4_sb_info *sbi = EXT4_SB(sb);
+        struct inode *inode = sbi->s_buddy_cache;
+        int blocks_per_page;
+        int block;
+        int pnum;
+        struct page *page;
+        int err;
+
+        /* Add group based on group descriptor*/
+        err = ext4_mb_add_groupinfo(sb, group, desc);
+        if (err)
+                return err;
+
+        /*
+         * Cache pages containing dynamic mb_alloc datas (buddy and bitmap
+         * datas) are set not up to date so that they will be re-initilaized
+         * during the next call to ext4_mb_load_buddy
+         */
+
+        /* Set buddy page as not up to date */
+        blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+        block = group * 2;
+        pnum = block / blocks_per_page;
+        page = find_get_page(inode->i_mapping, pnum);
+        if (page != NULL) {
+                ClearPageUptodate(page);
+                page_cache_release(page);
+        }
+
+        /* Set bitmap page as not up to date */
+        block++;
+        pnum = block / blocks_per_page;
+        page = find_get_page(inode->i_mapping, pnum);
+        if (page != NULL) {
+                ClearPageUptodate(page);
+                page_cache_release(page);
+        }
+
+        return 0;
+}
+
+/*
+ * Update an existing group.
+ * This function is used for online resize
+ */
+void ext4_mb_update_group_info(struct ext4_group_info *grp, ext4_grpblk_t add)
+{
+        grp->bb_free += add;
+}
+
 static int ext4_mb_init_backend(struct super_block *sb)
 {
         ext4_group_t i;
-        int j, len, metalen;
+        int metalen;
         struct ext4_sb_info *sbi = EXT4_SB(sb);
-        int num_meta_group_infos =
-                (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) >>
-                        EXT4_DESC_PER_BLOCK_BITS(sb);
+        struct ext4_super_block *es = sbi->s_es;
+        int num_meta_group_infos;
+        int num_meta_group_infos_max;
+        int array_size;
         struct ext4_group_info **meta_group_info;
+        struct ext4_group_desc *desc;
+
+        /* This is the number of blocks used by GDT */
+        num_meta_group_infos = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) -
+                                1) >> EXT4_DESC_PER_BLOCK_BITS(sb);
+
+        /*
+         * This is the total number of blocks used by GDT including
+         * the number of reserved blocks for GDT.
+         * The s_group_info array is allocated with this value
+         * to allow a clean online resize without a complex
+         * manipulation of pointer.
+         * The drawback is the unused memory when no resize
+         * occurs but it's very low in terms of pages
+         * (see comments below)
+         * Need to handle this properly when META_BG resizing is allowed
+         */
+        num_meta_group_infos_max = num_meta_group_infos +
+                                le16_to_cpu(es->s_reserved_gdt_blocks);
 
+        /*
+         * array_size is the size of s_group_info array. We round it
+         * to the next power of two because this approximation is done
+         * internally by kmalloc so we can have some more memory
+         * for free here (e.g. may be used for META_BG resize).
+         */
+        array_size = 1;
+        while (array_size < sizeof(*sbi->s_group_info) *
+               num_meta_group_infos_max)
+                array_size = array_size << 1;
         /* An 8TB filesystem with 64-bit pointers requires a 4096 byte
          * kmalloc. A 128kb malloc should suffice for a 256TB filesystem.
          * So a two level scheme suffices for now. */
-        sbi->s_group_info = kmalloc(sizeof(*sbi->s_group_info) *
-                                    num_meta_group_infos, GFP_KERNEL);
+        sbi->s_group_info = kmalloc(array_size, GFP_KERNEL);
         if (sbi->s_group_info == NULL) {
                 printk(KERN_ERR "EXT4-fs: can't allocate buddy meta group\n");
                 return -ENOMEM;
@@ -2256,63 +2448,15 @@ static int ext4_mb_init_backend(struct super_block *sb)
                 sbi->s_group_info[i] = meta_group_info;
         }
 
-        /*
-         * calculate needed size. if change bb_counters size,
-         * don't forget about ext4_mb_generate_buddy()
-         */
-        len = sizeof(struct ext4_group_info);
-        len += sizeof(unsigned short) * (sb->s_blocksize_bits + 2);
         for (i = 0; i < sbi->s_groups_count; i++) {
-                struct ext4_group_desc *desc;
-
-                meta_group_info =
-                        sbi->s_group_info[i >> EXT4_DESC_PER_BLOCK_BITS(sb)];
-                j = i & (EXT4_DESC_PER_BLOCK(sb) - 1);
-
-                meta_group_info[j] = kzalloc(len, GFP_KERNEL);
-                if (meta_group_info[j] == NULL) {
-                        printk(KERN_ERR "EXT4-fs: can't allocate buddy mem\n");
-                        goto err_freebuddy;
-                }
                 desc = ext4_get_group_desc(sb, i, NULL);
                 if (desc == NULL) {
                         printk(KERN_ERR
                                 "EXT4-fs: can't read descriptor %lu\n", i);
-                        i++;
                         goto err_freebuddy;
                 }
-                memset(meta_group_info[j], 0, len);
-                set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT,
-                        &(meta_group_info[j]->bb_state));
-
-                /*
-                 * initialize bb_free to be able to skip
-                 * empty groups without initialization
-                 */
-                if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
-                        meta_group_info[j]->bb_free =
-                                ext4_free_blocks_after_init(sb, i, desc);
-                } else {
-                        meta_group_info[j]->bb_free =
-                                le16_to_cpu(desc->bg_free_blocks_count);
-                }
-
-                INIT_LIST_HEAD(&meta_group_info[j]->bb_prealloc_list);
-
-#ifdef DOUBLE_CHECK
-                {
-                        struct buffer_head *bh;
-                        meta_group_info[j]->bb_bitmap =
-                                kmalloc(sb->s_blocksize, GFP_KERNEL);
-                        BUG_ON(meta_group_info[j]->bb_bitmap == NULL);
-                        bh = read_block_bitmap(sb, i);
-                        BUG_ON(bh == NULL);
-                        memcpy(meta_group_info[j]->bb_bitmap, bh->b_data,
-                                        sb->s_blocksize);
-                        put_bh(bh);
-                }
-#endif
-
+                if (ext4_mb_add_groupinfo(sb, i, desc) != 0)
+                        goto err_freebuddy;
         }
 
         return 0;
@@ -2336,6 +2480,7 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
         unsigned i;
         unsigned offset;
         unsigned max;
+        int ret;
 
         if (!test_opt(sb, MBALLOC))
                 return 0;
@@ -2370,12 +2515,12 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
         } while (i <= sb->s_blocksize_bits + 1);
 
         /* init file for buddy data */
-        i = ext4_mb_init_backend(sb);
-        if (i) {
+        ret = ext4_mb_init_backend(sb);
+        if (ret != 0) {
                 clear_opt(sbi->s_mount_opt, MBALLOC);
                 kfree(sbi->s_mb_offsets);
                 kfree(sbi->s_mb_maxs);
-                return i;
+                return ret;
         }
 
         spin_lock_init(&sbi->s_md_lock);
@@ -2548,8 +2693,7 @@ ext4_mb_free_committed_blocks(struct super_block *sb)
                 ext4_lock_group(sb, md->group);
                 for (i = 0; i < md->num; i++) {
                         mb_debug(" %u", md->blocks[i]);
-                        err = mb_free_blocks(NULL, &e4b, md->blocks[i], 1);
-                        BUG_ON(err != 0);
+                        mb_free_blocks(NULL, &e4b, md->blocks[i], 1);
                 }
                 mb_debug("\n");
                 ext4_unlock_group(sb, md->group);
@@ -2575,25 +2719,24 @@ ext4_mb_free_committed_blocks(struct super_block *sb)
 
 
 
-#define MB_PROC_VALUE_READ(name)                                \
-static int ext4_mb_read_##name(char *page, char **start,        \
-                off_t off, int count, int *eof, void *data)     \
+#define MB_PROC_FOPS(name)                                      \
+static int ext4_mb_##name##_proc_show(struct seq_file *m, void *v)      \
 {                                                               \
-        struct ext4_sb_info *sbi = data;                        \
-        int len;                                                \
-        *eof = 1;                                               \
-        if (off != 0)                                           \
-                return 0;                                       \
-        len = sprintf(page, "%ld\n", sbi->s_mb_##name);         \
-        *start = page;                                          \
-        return len;                                             \
-}
-
-#define MB_PROC_VALUE_WRITE(name)                               \
-static int ext4_mb_write_##name(struct file *file,              \
-                const char __user *buf, unsigned long cnt, void *data)  \
+        struct ext4_sb_info *sbi = m->private;                  \
+                                                                \
+        seq_printf(m, "%ld\n", sbi->s_mb_##name);               \
+        return 0;                                               \
+}                                                               \
+                                                                \
+static int ext4_mb_##name##_proc_open(struct inode *inode, struct file *file)\
+{                                                               \
+        return single_open(file, ext4_mb_##name##_proc_show, PDE(inode)->data);\
+}                                                               \
+                                                                \
+static ssize_t ext4_mb_##name##_proc_write(struct file *file,   \
+                const char __user *buf, size_t cnt, loff_t *ppos)       \
 {                                                               \
-        struct ext4_sb_info *sbi = data;                        \
+        struct ext4_sb_info *sbi = PDE(file->f_path.dentry->d_inode)->data;\
         char str[32];                                           \
         long value;                                             \
         if (cnt >= sizeof(str))                                 \
@@ -2605,31 +2748,32 @@ static int ext4_mb_write_##name(struct file *file,		\
                 return -ERANGE;                                 \
         sbi->s_mb_##name = value;                               \
         return cnt;                                             \
-}
+}                                                               \
+                                                                \
+static const struct file_operations ext4_mb_##name##_proc_fops = {      \
+        .owner          = THIS_MODULE,                          \
+        .open           = ext4_mb_##name##_proc_open,           \
+        .read           = seq_read,                             \
+        .llseek         = seq_lseek,                            \
+        .release        = single_release,                       \
+        .write          = ext4_mb_##name##_proc_write,          \
+};
 
-MB_PROC_VALUE_READ(stats);
-MB_PROC_VALUE_WRITE(stats);
-MB_PROC_VALUE_READ(max_to_scan);
-MB_PROC_VALUE_WRITE(max_to_scan);
-MB_PROC_VALUE_READ(min_to_scan);
-MB_PROC_VALUE_WRITE(min_to_scan);
-MB_PROC_VALUE_READ(order2_reqs);
-MB_PROC_VALUE_WRITE(order2_reqs);
-MB_PROC_VALUE_READ(stream_request);
-MB_PROC_VALUE_WRITE(stream_request);
-MB_PROC_VALUE_READ(group_prealloc);
-MB_PROC_VALUE_WRITE(group_prealloc);
+MB_PROC_FOPS(stats);
+MB_PROC_FOPS(max_to_scan);
+MB_PROC_FOPS(min_to_scan);
+MB_PROC_FOPS(order2_reqs);
+MB_PROC_FOPS(stream_request);
+MB_PROC_FOPS(group_prealloc);
 
 #define MB_PROC_HANDLER(name, var)                                      \
 do {                                                                    \
-        proc = create_proc_entry(name, mode, sbi->s_mb_proc);           \
+        proc = proc_create_data(name, mode, sbi->s_mb_proc,             \
+                                &ext4_mb_##var##_proc_fops, sbi);       \
         if (proc == NULL) {                                             \
                 printk(KERN_ERR "EXT4-fs: can't to create %s\n", name); \
                 goto err_out;                                           \
         }                                                               \
-        proc->data = sbi;                                               \
-        proc->read_proc  = ext4_mb_read_##var ;                         \
-        proc->write_proc = ext4_mb_write_##var;                         \
 } while (0)
 
 static int ext4_mb_init_per_dev_proc(struct super_block *sb)
@@ -2639,6 +2783,10 @@ static int ext4_mb_init_per_dev_proc(struct super_block *sb)
         struct proc_dir_entry *proc;
         char devname[64];
 
+        if (proc_root_ext4 == NULL) {
+                sbi->s_mb_proc = NULL;
+                return -EINVAL;
+        }
         bdevname(sb->s_bdev, devname);
         sbi->s_mb_proc = proc_mkdir(devname, proc_root_ext4);
 
@@ -2747,7 +2895,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
 
 
         err = -EIO;
-        bitmap_bh = read_block_bitmap(sb, ac->ac_b_ex.fe_group);
+        bitmap_bh = ext4_read_block_bitmap(sb, ac->ac_b_ex.fe_group);
         if (!bitmap_bh)
                 goto out_err;
 
@@ -2816,7 +2964,23 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac,
         le16_add_cpu(&gdp->bg_free_blocks_count, -ac->ac_b_ex.fe_len);
         gdp->bg_checksum = ext4_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp);
         spin_unlock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group));
-        percpu_counter_sub(&sbi->s_freeblocks_counter, ac->ac_b_ex.fe_len);
+
+        /*
+         * free blocks account has already be reduced/reserved
+         * at write_begin() time for delayed allocation
+         * do not double accounting
+         */
+        if (!(ac->ac_flags & EXT4_MB_DELALLOC_RESERVED))
+                percpu_counter_sub(&sbi->s_freeblocks_counter,
+                                        ac->ac_b_ex.fe_len);
+
+        if (sbi->s_log_groups_per_flex) {
+                ext4_group_t flex_group = ext4_flex_group(sbi,
+                                                          ac->ac_b_ex.fe_group);
+                spin_lock(sb_bgl_lock(sbi, flex_group));
+                sbi->s_flex_groups[flex_group].free_blocks -= ac->ac_b_ex.fe_len;
+                spin_unlock(sb_bgl_lock(sbi, flex_group));
+        }
 
         err = ext4_journal_dirty_metadata(handle, bitmap_bh);
         if (err)
@@ -3473,8 +3637,6 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
                 if (bit >= end)
                         break;
                 next = mb_find_next_bit(bitmap_bh->b_data, end, bit);
-                if (next > end)
-                        next = end;
                 start = group * EXT4_BLOCKS_PER_GROUP(sb) + bit +
                                 le32_to_cpu(sbi->s_es->s_first_data_block);
                 mb_debug("    free preallocated %u/%u in group %u\n",
@@ -3569,7 +3731,7 @@ ext4_mb_discard_group_preallocations(struct super_block *sb,
         if (list_empty(&grp->bb_prealloc_list))
                 return 0;
 
-        bitmap_bh = read_block_bitmap(sb, group);
+        bitmap_bh = ext4_read_block_bitmap(sb, group);
         if (bitmap_bh == NULL) {
                 /* error handling here */
                 ext4_mb_release_desc(&e4b);
@@ -3743,7 +3905,7 @@ repeat:
                 err = ext4_mb_load_buddy(sb, group, &e4b);
                 BUG_ON(err != 0); /* error handling here */
 
-                bitmap_bh = read_block_bitmap(sb, group);
+                bitmap_bh = ext4_read_block_bitmap(sb, group);
                 if (bitmap_bh == NULL) {
                         /* error handling here */
                         ext4_mb_release_desc(&e4b);
@@ -4011,10 +4173,21 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
         sbi = EXT4_SB(sb);
 
         if (!test_opt(sb, MBALLOC)) {
-                block = ext4_new_blocks_old(handle, ar->inode, ar->goal,
+                block = ext4_old_new_blocks(handle, ar->inode, ar->goal,
                                             &(ar->len), errp);
                 return block;
         }
+        if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag) {
+                /*
+                 * With delalloc we already reserved the blocks
+                 */
+                ar->len = ext4_has_free_blocks(sbi, ar->len);
+        }
+
+        if (ar->len == 0) {
+                *errp = -ENOSPC;
+                return 0;
+        }
 
         while (ar->len && DQUOT_ALLOC_BLOCK(ar->inode, ar->len)) {
                 ar->flags |= EXT4_MB_HINT_NOPREALLOC;
@@ -4026,10 +4199,14 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
         }
         inquota = ar->len;
 
+        if (EXT4_I(ar->inode)->i_delalloc_reserved_flag)
+                ar->flags |= EXT4_MB_DELALLOC_RESERVED;
+
         ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
         if (!ac) {
+                ar->len = 0;
                 *errp = -ENOMEM;
-                return 0;
+                goto out1;
         }
 
         ext4_mb_poll_new_transaction(sb, handle);
@@ -4037,12 +4214,11 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle,
         *errp = ext4_mb_initialize_context(ac, ar);
         if (*errp) {
                 ar->len = 0;
-                goto out;
+                goto out2;
         }
 
         ac->ac_op = EXT4_MB_HISTORY_PREALLOC;
         if (!ext4_mb_use_preallocated(ac)) {
-
                 ac->ac_op = EXT4_MB_HISTORY_ALLOC;
                 ext4_mb_normalize_request(ac, ar);
 repeat:
@@ -4085,11 +4261,12 @@ repeat:
 
         ext4_mb_release_context(ac);
 
-out:
+out2:
+        kmem_cache_free(ext4_ac_cachep, ac);
+out1:
         if (ar->len < inquota)
                 DQUOT_FREE_BLOCK(ar->inode, inquota - ar->len);
 
-        kmem_cache_free(ext4_ac_cachep, ac);
         return block;
 }
 static void ext4_mb_poll_new_transaction(struct super_block *sb,
@@ -4242,7 +4419,7 @@ do_more:
                 overflow = bit + count - EXT4_BLOCKS_PER_GROUP(sb);
                 count -= overflow;
         }
-        bitmap_bh = read_block_bitmap(sb, block_group);
+        bitmap_bh = ext4_read_block_bitmap(sb, block_group);
         if (!bitmap_bh)
                 goto error_return;
         gdp = ext4_get_group_desc(sb, block_group, &gd_bh);
@@ -4309,10 +4486,9 @@ do_more:
                 ext4_mb_free_metadata(handle, &e4b, block_group, bit, count);
         } else {
                 ext4_lock_group(sb, block_group);
-                err = mb_free_blocks(inode, &e4b, bit, count);
+                mb_free_blocks(inode, &e4b, bit, count);
                 ext4_mb_return_to_preallocation(inode, &e4b, block, count);
                 ext4_unlock_group(sb, block_group);
-                BUG_ON(err != 0);
         }
 
         spin_lock(sb_bgl_lock(sbi, block_group));
@@ -4321,6 +4497,13 @@ do_more:
         spin_unlock(sb_bgl_lock(sbi, block_group));
         percpu_counter_add(&sbi->s_freeblocks_counter, count);
 
+        if (sbi->s_log_groups_per_flex) {
+                ext4_group_t flex_group = ext4_flex_group(sbi, block_group);
+                spin_lock(sb_bgl_lock(sbi, flex_group));
+                sbi->s_flex_groups[flex_group].free_blocks += count;
+                spin_unlock(sb_bgl_lock(sbi, flex_group));
+        }
+
         ext4_mb_release_desc(&e4b);
 
         *freed += count;