if (bh_uptodate_or_lock(bh[i]))
continue;
+ spin_lock(sb_bgl_lock(EXT4_SB(sb), first_group + i));
if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
ext4_init_block_bitmap(sb, bh[i],
first_group + i, desc);
set_buffer_uptodate(bh[i]);
unlock_buffer(bh[i]);
+ spin_unlock(sb_bgl_lock(EXT4_SB(sb), first_group + i));
continue;
}
+ spin_unlock(sb_bgl_lock(EXT4_SB(sb), first_group + i));
get_bh(bh[i]);
bh[i]->b_end_io = end_buffer_read_sync;
submit_bh(READ, bh[i]);
#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;
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;
}
- 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 = ext4_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;
int ext4_mb_init(struct super_block *sb, int needs_recovery)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
- unsigned i;
+ unsigned i, j;
unsigned offset;
unsigned max;
int ret;
sbi->s_mb_history_filter = EXT4_MB_HISTORY_DEFAULT;
sbi->s_mb_group_prealloc = MB_DEFAULT_GROUP_PREALLOC;
- i = sizeof(struct ext4_locality_group) * NR_CPUS;
+ i = sizeof(struct ext4_locality_group) * nr_cpu_ids;
sbi->s_locality_groups = kmalloc(i, GFP_KERNEL);
if (sbi->s_locality_groups == NULL) {
clear_opt(sbi->s_mount_opt, MBALLOC);
kfree(sbi->s_mb_maxs);
return -ENOMEM;
}
- for (i = 0; i < NR_CPUS; i++) {
+ for (i = 0; i < nr_cpu_ids; i++) {
struct ext4_locality_group *lg;
lg = &sbi->s_locality_groups[i];
mutex_init(&lg->lg_mutex);
- INIT_LIST_HEAD(&lg->lg_prealloc_list);
+ for (j = 0; j < PREALLOC_TB_SIZE; j++)
+ INIT_LIST_HEAD(&lg->lg_prealloc_list[j]);
spin_lock_init(&lg->lg_prealloc_lock);
}
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,
struct ext4_prealloc_space *pa)
{
unsigned int len = ac->ac_o_ex.fe_len;
+
ext4_get_group_no_and_offset(ac->ac_sb, pa->pa_pstart,
&ac->ac_b_ex.fe_group,
&ac->ac_b_ex.fe_start);
static noinline_for_stack int
ext4_mb_use_preallocated(struct ext4_allocation_context *ac)
{
+ int order, i;
struct ext4_inode_info *ei = EXT4_I(ac->ac_inode);
struct ext4_locality_group *lg;
struct ext4_prealloc_space *pa;
lg = ac->ac_lg;
if (lg == NULL)
return 0;
-
- rcu_read_lock();
- list_for_each_entry_rcu(pa, &lg->lg_prealloc_list, pa_inode_list) {
- spin_lock(&pa->pa_lock);
- if (pa->pa_deleted == 0 && pa->pa_free >= ac->ac_o_ex.fe_len) {
- atomic_inc(&pa->pa_count);
- ext4_mb_use_group_pa(ac, pa);
+ order = fls(ac->ac_o_ex.fe_len) - 1;
+ if (order > PREALLOC_TB_SIZE - 1)
+ /* The max size of hash table is PREALLOC_TB_SIZE */
+ order = PREALLOC_TB_SIZE - 1;
+
+ for (i = order; i < PREALLOC_TB_SIZE; i++) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(pa, &lg->lg_prealloc_list[i],
+ pa_inode_list) {
+ spin_lock(&pa->pa_lock);
+ if (pa->pa_deleted == 0 &&
+ pa->pa_free >= ac->ac_o_ex.fe_len) {
+ atomic_inc(&pa->pa_count);
+ ext4_mb_use_group_pa(ac, pa);
+ spin_unlock(&pa->pa_lock);
+ ac->ac_criteria = 20;
+ rcu_read_unlock();
+ return 1;
+ }
spin_unlock(&pa->pa_lock);
- ac->ac_criteria = 20;
- rcu_read_unlock();
- return 1;
}
- spin_unlock(&pa->pa_lock);
+ rcu_read_unlock();
}
- rcu_read_unlock();
-
return 0;
}
pa->pa_free = pa->pa_len;
atomic_set(&pa->pa_count, 1);
spin_lock_init(&pa->pa_lock);
+ INIT_LIST_HEAD(&pa->pa_inode_list);
pa->pa_deleted = 0;
pa->pa_linear = 1;
list_add(&pa->pa_group_list, &grp->bb_prealloc_list);
ext4_unlock_group(sb, ac->ac_b_ex.fe_group);
- spin_lock(pa->pa_obj_lock);
- list_add_tail_rcu(&pa->pa_inode_list, &lg->lg_prealloc_list);
- spin_unlock(pa->pa_obj_lock);
-
+ /*
+ * We will later add the new pa to the right bucket
+ * after updating the pa_free in ext4_mb_release_context
+ */
return 0;
}
bitmap_bh = ext4_read_block_bitmap(sb, group);
if (bitmap_bh == NULL) {
- /* error handling here */
- ext4_mb_release_desc(&e4b);
- BUG_ON(bitmap_bh == NULL);
+ ext4_error(sb, __func__, "Error in reading block "
+ "bitmap for %lu\n", group);
+ return 0;
}
err = ext4_mb_load_buddy(sb, group, &e4b);
- BUG_ON(err != 0); /* error handling here */
+ if (err) {
+ ext4_error(sb, __func__, "Error in loading buddy "
+ "information for %lu\n", group);
+ put_bh(bitmap_bh);
+ return 0;
+ }
if (needed == 0)
needed = EXT4_BLOCKS_PER_GROUP(sb) + 1;
- grp = ext4_get_group_info(sb, group);
INIT_LIST_HEAD(&list);
-
ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
repeat:
ext4_lock_group(sb, group);
ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, NULL);
err = ext4_mb_load_buddy(sb, group, &e4b);
- BUG_ON(err != 0); /* error handling here */
+ if (err) {
+ ext4_error(sb, __func__, "Error in loading buddy "
+ "information for %lu\n", group);
+ continue;
+ }
bitmap_bh = ext4_read_block_bitmap(sb, group);
if (bitmap_bh == NULL) {
- /* error handling here */
+ ext4_error(sb, __func__, "Error in reading block "
+ "bitmap for %lu\n", group);
ext4_mb_release_desc(&e4b);
- BUG_ON(bitmap_bh == NULL);
+ continue;
}
ext4_lock_group(sb, group);
}
+static noinline_for_stack void
+ext4_mb_discard_lg_preallocations(struct super_block *sb,
+ struct ext4_locality_group *lg,
+ int order, int total_entries)
+{
+ ext4_group_t group = 0;
+ struct ext4_buddy e4b;
+ struct list_head discard_list;
+ struct ext4_prealloc_space *pa, *tmp;
+ struct ext4_allocation_context *ac;
+
+ mb_debug("discard locality group preallocation\n");
+
+ INIT_LIST_HEAD(&discard_list);
+ ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
+
+ spin_lock(&lg->lg_prealloc_lock);
+ list_for_each_entry_rcu(pa, &lg->lg_prealloc_list[order],
+ pa_inode_list) {
+ spin_lock(&pa->pa_lock);
+ if (atomic_read(&pa->pa_count)) {
+ /*
+ * This is the pa that we just used
+ * for block allocation. So don't
+ * free that
+ */
+ spin_unlock(&pa->pa_lock);
+ continue;
+ }
+ if (pa->pa_deleted) {
+ spin_unlock(&pa->pa_lock);
+ continue;
+ }
+ /* only lg prealloc space */
+ BUG_ON(!pa->pa_linear);
+
+ /* seems this one can be freed ... */
+ pa->pa_deleted = 1;
+ spin_unlock(&pa->pa_lock);
+
+ list_del_rcu(&pa->pa_inode_list);
+ list_add(&pa->u.pa_tmp_list, &discard_list);
+
+ total_entries--;
+ if (total_entries <= 5) {
+ /*
+ * we want to keep only 5 entries
+ * allowing it to grow to 8. This
+ * mak sure we don't call discard
+ * soon for this list.
+ */
+ break;
+ }
+ }
+ spin_unlock(&lg->lg_prealloc_lock);
+
+ list_for_each_entry_safe(pa, tmp, &discard_list, u.pa_tmp_list) {
+
+ ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, NULL);
+ if (ext4_mb_load_buddy(sb, group, &e4b)) {
+ ext4_error(sb, __func__, "Error in loading buddy "
+ "information for %lu\n", group);
+ continue;
+ }
+ ext4_lock_group(sb, group);
+ list_del(&pa->pa_group_list);
+ ext4_mb_release_group_pa(&e4b, pa, ac);
+ ext4_unlock_group(sb, group);
+
+ ext4_mb_release_desc(&e4b);
+ list_del(&pa->u.pa_tmp_list);
+ call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback);
+ }
+ if (ac)
+ kmem_cache_free(ext4_ac_cachep, ac);
+}
+
+/*
+ * We have incremented pa_count. So it cannot be freed at this
+ * point. Also we hold lg_mutex. So no parallel allocation is
+ * possible from this lg. That means pa_free cannot be updated.
+ *
+ * A parallel ext4_mb_discard_group_preallocations is possible.
+ * which can cause the lg_prealloc_list to be updated.
+ */
+
+static void ext4_mb_add_n_trim(struct ext4_allocation_context *ac)
+{
+ int order, added = 0, lg_prealloc_count = 1;
+ struct super_block *sb = ac->ac_sb;
+ struct ext4_locality_group *lg = ac->ac_lg;
+ struct ext4_prealloc_space *tmp_pa, *pa = ac->ac_pa;
+
+ order = fls(pa->pa_free) - 1;
+ if (order > PREALLOC_TB_SIZE - 1)
+ /* The max size of hash table is PREALLOC_TB_SIZE */
+ order = PREALLOC_TB_SIZE - 1;
+ /* Add the prealloc space to lg */
+ rcu_read_lock();
+ list_for_each_entry_rcu(tmp_pa, &lg->lg_prealloc_list[order],
+ pa_inode_list) {
+ spin_lock(&tmp_pa->pa_lock);
+ if (tmp_pa->pa_deleted) {
+ spin_unlock(&pa->pa_lock);
+ continue;
+ }
+ if (!added && pa->pa_free < tmp_pa->pa_free) {
+ /* Add to the tail of the previous entry */
+ list_add_tail_rcu(&pa->pa_inode_list,
+ &tmp_pa->pa_inode_list);
+ added = 1;
+ /*
+ * we want to count the total
+ * number of entries in the list
+ */
+ }
+ spin_unlock(&tmp_pa->pa_lock);
+ lg_prealloc_count++;
+ }
+ if (!added)
+ list_add_tail_rcu(&pa->pa_inode_list,
+ &lg->lg_prealloc_list[order]);
+ rcu_read_unlock();
+
+ /* Now trim the list to be not more than 8 elements */
+ if (lg_prealloc_count > 8) {
+ ext4_mb_discard_lg_preallocations(sb, lg,
+ order, lg_prealloc_count);
+ return;
+ }
+ return ;
+}
+
/*
* release all resource we used in allocation
*/
static int ext4_mb_release_context(struct ext4_allocation_context *ac)
{
- if (ac->ac_pa) {
- if (ac->ac_pa->pa_linear) {
+ struct ext4_prealloc_space *pa = ac->ac_pa;
+ if (pa) {
+ if (pa->pa_linear) {
/* see comment in ext4_mb_use_group_pa() */
- spin_lock(&ac->ac_pa->pa_lock);
- ac->ac_pa->pa_pstart += ac->ac_b_ex.fe_len;
- ac->ac_pa->pa_lstart += ac->ac_b_ex.fe_len;
- ac->ac_pa->pa_free -= ac->ac_b_ex.fe_len;
- ac->ac_pa->pa_len -= ac->ac_b_ex.fe_len;
- spin_unlock(&ac->ac_pa->pa_lock);
+ spin_lock(&pa->pa_lock);
+ pa->pa_pstart += ac->ac_b_ex.fe_len;
+ pa->pa_lstart += ac->ac_b_ex.fe_len;
+ pa->pa_free -= ac->ac_b_ex.fe_len;
+ pa->pa_len -= ac->ac_b_ex.fe_len;
+ spin_unlock(&pa->pa_lock);
+ /*
+ * We want to add the pa to the right bucket.
+ * Remove it from the list and while adding
+ * make sure the list to which we are adding
+ * doesn't grow big.
+ */
+ if (likely(pa->pa_free)) {
+ spin_lock(pa->pa_obj_lock);
+ list_del_rcu(&pa->pa_inode_list);
+ spin_unlock(pa->pa_obj_lock);
+ ext4_mb_add_n_trim(ac);
+ }
}
- ext4_mb_put_pa(ac, ac->ac_sb, ac->ac_pa);
+ ext4_mb_put_pa(ac, ac->ac_sb, pa);
}
if (ac->ac_bitmap_page)
page_cache_release(ac->ac_bitmap_page);
&(ar->len), errp);
return block;
}
- ar->len = ext4_has_free_blocks(sbi, ar->len);
+ 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;
}
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;
count -= overflow;
}
bitmap_bh = ext4_read_block_bitmap(sb, block_group);
- if (!bitmap_bh)
+ if (!bitmap_bh) {
+ err = -EIO;
goto error_return;
+ }
gdp = ext4_get_group_desc(sb, block_group, &gd_bh);
- if (!gdp)
+ if (!gdp) {
+ err = -EIO;
goto error_return;
+ }
if (in_range(ext4_block_bitmap(sb, gdp), block, count) ||
in_range(ext4_inode_bitmap(sb, gdp), block, count) ||