void ext4_delete_inode (struct inode * inode)
{
handle_t *handle;
+ int err;
if (ext4_should_order_data(inode))
ext4_begin_ordered_truncate(inode, 0);
if (is_bad_inode(inode))
goto no_delete;
- handle = start_transaction(inode);
+ handle = ext4_journal_start(inode, blocks_for_truncate(inode)+3);
if (IS_ERR(handle)) {
+ ext4_std_error(inode->i_sb, PTR_ERR(handle));
/*
* If we're going to skip the normal cleanup, we still need to
* make sure that the in-core orphan linked list is properly
if (IS_SYNC(inode))
handle->h_sync = 1;
inode->i_size = 0;
+ err = ext4_mark_inode_dirty(handle, inode);
+ if (err) {
+ ext4_warning(inode->i_sb, __func__,
+ "couldn't mark inode dirty (err %d)", err);
+ goto stop_handle;
+ }
if (inode->i_blocks)
ext4_truncate(inode);
+
+ /*
+ * ext4_ext_truncate() doesn't reserve any slop when it
+ * restarts journal transactions; therefore there may not be
+ * enough credits left in the handle to remove the inode from
+ * the orphan list and set the dtime field.
+ */
+ if (handle->h_buffer_credits < 3) {
+ err = ext4_journal_extend(handle, 3);
+ if (err > 0)
+ err = ext4_journal_restart(handle, 3);
+ if (err != 0) {
+ ext4_warning(inode->i_sb, __func__,
+ "couldn't extend journal (err %d)", err);
+ stop_handle:
+ ext4_journal_stop(handle);
+ goto no_delete;
+ }
+ }
+
/*
* Kill off the orphan record which ext4_truncate created.
* AKPM: I think this can be inside the above `if'.
struct ext4_inode_info *ei = EXT4_I(inode);
int count = 0;
ext4_fsblk_t first_block = 0;
+ loff_t disksize;
J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
* protect it if you're about to implement concurrent
* ext4_get_block() -bzzz
*/
- if (!err && extend_disksize && inode->i_size > ei->i_disksize)
- ei->i_disksize = inode->i_size;
+ if (!err && extend_disksize) {
+ disksize = ((loff_t) iblock + count) << inode->i_blkbits;
+ if (disksize > i_size_read(inode))
+ disksize = i_size_read(inode);
+ if (disksize > ei->i_disksize)
+ ei->i_disksize = disksize;
+ }
if (err)
goto cleanup;
do {
if (cur_logical >= logical + blocks)
break;
-
if (buffer_delay(bh)) {
bh->b_blocknr = pblock;
clear_buffer_delay(bh);
- } else if (buffer_mapped(bh)) {
+ } else if (buffer_mapped(bh))
BUG_ON(bh->b_blocknr != pblock);
- }
cur_logical++;
pblock++;
if (buffer_delay(lbh))
mpage_put_bnr_to_bhs(mpd, next, &new);
- /* go for the remaining blocks */
- next += new.b_size >> mpd->inode->i_blkbits;
- remain -= new.b_size;
- }
+ /* go for the remaining blocks */
+ next += new.b_size >> mpd->inode->i_blkbits;
+ remain -= new.b_size;
+ }
}
#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | (1 << BH_Delay))
static int ext4_da_get_block_write(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
{
- int ret, needed_blocks = ext4_writepage_trans_blocks(inode);
+ int ret;
unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
loff_t disksize = EXT4_I(inode)->i_disksize;
handle_t *handle = NULL;
- if (create) {
- handle = ext4_journal_start(inode, needed_blocks);
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto out;
- }
+ handle = ext4_journal_current_handle();
+ if (!handle) {
+ ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
+ bh_result, 0, 0, 0);
+ BUG_ON(!ret);
+ } else {
+ ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
+ bh_result, create, 0, EXT4_DELALLOC_RSVED);
}
- ret = ext4_get_blocks_wrap(handle, inode, iblock, max_blocks,
- bh_result, create, 0, EXT4_DELALLOC_RSVED);
if (ret > 0) {
bh_result->b_size = (ret << inode->i_blkbits);
up_write(&EXT4_I(inode)->i_data_sem);
if (EXT4_I(inode)->i_disksize == disksize) {
- if (handle == NULL)
- handle = ext4_journal_start(inode, 1);
- if (!IS_ERR(handle))
- ext4_mark_inode_dirty(handle, inode);
+ ret = ext4_mark_inode_dirty(handle, inode);
+ return ret;
}
}
-
ret = 0;
}
+ return ret;
+}
-out:
- if (handle && !IS_ERR(handle))
- ext4_journal_stop(handle);
+static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh)
+{
+ /*
+ * unmapped buffer is possible for holes.
+ * delay buffer is possible with delayed allocation
+ */
+ return ((!buffer_mapped(bh) || buffer_delay(bh)) && buffer_dirty(bh));
+}
+static int ext4_normal_get_block_write(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int ret = 0;
+ unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+
+ /*
+ * we don't want to do block allocation in writepage
+ * so call get_block_wrap with create = 0
+ */
+ ret = ext4_get_blocks_wrap(NULL, inode, iblock, max_blocks,
+ bh_result, 0, 0, 0);
+ if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ ret = 0;
+ }
return ret;
}
-/* FIXME!! only support data=writeback mode */
+
+/*
+ * get called vi ext4_da_writepages after taking page lock (have journal handle)
+ * get called via journal_submit_inode_data_buffers (no journal handle)
+ * get called via shrink_page_list via pdflush (no journal handle)
+ * or grab_page_cache when doing write_begin (have journal handle)
+ */
static int ext4_da_writepage(struct page *page,
struct writeback_control *wbc)
{
- struct inode *inode = page->mapping->host;
- handle_t *handle = NULL;
int ret = 0;
- int err;
+ loff_t size;
+ unsigned long len;
+ struct buffer_head *page_bufs;
+ struct inode *inode = page->mapping->host;
- if (ext4_journal_current_handle())
- goto out_fail;
+ size = i_size_read(inode);
+ if (page->index == size >> PAGE_CACHE_SHIFT)
+ len = size & ~PAGE_CACHE_MASK;
+ else
+ len = PAGE_CACHE_SIZE;
- handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- goto out_fail;
+ if (page_has_buffers(page)) {
+ page_bufs = page_buffers(page);
+ if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+ ext4_bh_unmapped_or_delay)) {
+ /*
+ * We don't want to do block allocation
+ * So redirty the page and return
+ * We may reach here when we do a journal commit
+ * via journal_submit_inode_data_buffers.
+ * If we don't have mapping block we just ignore
+ * them. We can also reach here via shrink_page_list
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
+ } else {
+ /*
+ * The test for page_has_buffers() is subtle:
+ * We know the page is dirty but it lost buffers. That means
+ * that at some moment in time after write_begin()/write_end()
+ * has been called all buffers have been clean and thus they
+ * must have been written at least once. So they are all
+ * mapped and we can happily proceed with mapping them
+ * and writing the page.
+ *
+ * Try to initialize the buffer_heads and check whether
+ * all are mapped and non delay. We don't want to
+ * do block allocation here.
+ */
+ ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
+ ext4_normal_get_block_write);
+ if (!ret) {
+ page_bufs = page_buffers(page);
+ /* check whether all are mapped and non delay */
+ if (walk_page_buffers(NULL, page_bufs, 0, len, NULL,
+ ext4_bh_unmapped_or_delay)) {
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
+ } else {
+ /*
+ * We can't do block allocation here
+ * so just redity the page and unlock
+ * and return
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+ }
}
if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
- ret = nobh_writepage(page, ext4_get_block, wbc);
+ ret = nobh_writepage(page, ext4_normal_get_block_write, wbc);
else
- ret = block_write_full_page(page, ext4_get_block, wbc);
+ ret = block_write_full_page(page,
+ ext4_normal_get_block_write,
+ wbc);
- if (!ret && inode->i_size > EXT4_I(inode)->i_disksize) {
- EXT4_I(inode)->i_disksize = inode->i_size;
- ext4_mark_inode_dirty(handle, inode);
- }
-
- err = ext4_journal_stop(handle);
- if (!ret)
- ret = err;
- return ret;
-
-out_fail:
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
return ret;
}
+/*
+ * For now just follow the DIO way to estimate the max credits
+ * needed to write out EXT4_MAX_WRITEBACK_PAGES.
+ * todo: need to calculate the max credits need for
+ * extent based files, currently the DIO credits is based on
+ * indirect-blocks mapping way.
+ *
+ * Probably should have a generic way to calculate credits
+ * for DIO, writepages, and truncate
+ */
+#define EXT4_MAX_WRITEBACK_PAGES DIO_MAX_BLOCKS
+#define EXT4_MAX_WRITEBACK_CREDITS DIO_CREDITS
+
static int ext4_da_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
- return mpage_da_writepages(mapping, wbc, ext4_da_get_block_write);
+ struct inode *inode = mapping->host;
+ handle_t *handle = NULL;
+ int needed_blocks;
+ int ret = 0;
+ long to_write;
+ loff_t range_start = 0;
+
+ /*
+ * No pages to write? This is mainly a kludge to avoid starting
+ * a transaction for special inodes like journal inode on last iput()
+ * because that could violate lock ordering on umount
+ */
+ if (!mapping->nrpages)
+ return 0;
+
+ /*
+ * Estimate the worse case needed credits to write out
+ * EXT4_MAX_BUF_BLOCKS pages
+ */
+ needed_blocks = EXT4_MAX_WRITEBACK_CREDITS;
+
+ to_write = wbc->nr_to_write;
+ if (!wbc->range_cyclic) {
+ /*
+ * If range_cyclic is not set force range_cont
+ * and save the old writeback_index
+ */
+ wbc->range_cont = 1;
+ range_start = wbc->range_start;
+ }
+
+ while (!ret && to_write) {
+ /* start a new transaction*/
+ handle = ext4_journal_start(inode, needed_blocks);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out_writepages;
+ }
+ if (ext4_should_order_data(inode)) {
+ /*
+ * With ordered mode we need to add
+ * the inode to the journal handle
+ * when we do block allocation.
+ */
+ ret = ext4_jbd2_file_inode(handle, inode);
+ if (ret) {
+ ext4_journal_stop(handle);
+ goto out_writepages;
+ }
+
+ }
+ /*
+ * set the max dirty pages could be write at a time
+ * to fit into the reserved transaction credits
+ */
+ if (wbc->nr_to_write > EXT4_MAX_WRITEBACK_PAGES)
+ wbc->nr_to_write = EXT4_MAX_WRITEBACK_PAGES;
+
+ to_write -= wbc->nr_to_write;
+ ret = mpage_da_writepages(mapping, wbc,
+ ext4_da_get_block_write);
+ ext4_journal_stop(handle);
+ if (wbc->nr_to_write) {
+ /*
+ * There is no more writeout needed
+ * or we requested for a noblocking writeout
+ * and we found the device congested
+ */
+ to_write += wbc->nr_to_write;
+ break;
+ }
+ wbc->nr_to_write = to_write;
+ }
+
+out_writepages:
+ wbc->nr_to_write = to_write;
+ if (range_start)
+ wbc->range_start = range_start;
+ return ret;
}
static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
}
page = __grab_cache_page(mapping, index);
- if (!page)
- return -ENOMEM;
+ if (!page) {
+ ext4_journal_stop(handle);
+ ret = -ENOMEM;
+ goto out;
+ }
*pagep = page;
ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
return ret;
}
-static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh)
+/*
+ * Check if we should update i_disksize
+ * when write to the end of file but not require block allocation
+ */
+static int ext4_da_should_update_i_disksize(struct page *page,
+ unsigned long offset)
{
- return !buffer_mapped(bh) || buffer_delay(bh);
+ struct buffer_head *bh;
+ struct inode *inode = page->mapping->host;
+ unsigned int idx;
+ int i;
+
+ bh = page_buffers(page);
+ idx = offset >> inode->i_blkbits;
+
+ for (i=0; i < idx; i++)
+ bh = bh->b_this_page;
+
+ if (!buffer_mapped(bh) || (buffer_delay(bh)))
+ return 0;
+ return 1;
}
static int ext4_da_write_end(struct file *file,
int ret = 0, ret2;
handle_t *handle = ext4_journal_current_handle();
loff_t new_i_size;
+ unsigned long start, end;
+
+ start = pos & (PAGE_CACHE_SIZE - 1);
+ end = start + copied -1;
/*
* generic_write_end() will run mark_inode_dirty() if i_size
*/
new_i_size = pos + copied;
- if (new_i_size > EXT4_I(inode)->i_disksize)
- if (!walk_page_buffers(NULL, page_buffers(page),
- 0, len, NULL, ext4_bh_unmapped_or_delay)){
- /*
- * Updating i_disksize when extending file without
- * needing block allocation
- */
- if (ext4_should_order_data(inode))
- ret = ext4_jbd2_file_inode(handle, inode);
+ if (new_i_size > EXT4_I(inode)->i_disksize) {
+ if (ext4_da_should_update_i_disksize(page, end)) {
+ down_write(&EXT4_I(inode)->i_data_sem);
+ if (new_i_size > EXT4_I(inode)->i_disksize) {
+ /*
+ * Updating i_disksize when extending file
+ * without needing block allocation
+ */
+ if (ext4_should_order_data(inode))
+ ret = ext4_jbd2_file_inode(handle,
+ inode);
- EXT4_I(inode)->i_disksize = new_i_size;
+ EXT4_I(inode)->i_disksize = new_i_size;
+ }
+ up_write(&EXT4_I(inode)->i_data_sem);
}
+ }
ret2 = generic_write_end(file, mapping, pos, len, copied,
page, fsdata);
copied = ret2;
struct inode *inode = page->mapping->host;
if (test_opt(inode->i_sb, NOBH))
- return nobh_writepage(page, ext4_get_block, wbc);
+ return nobh_writepage(page,
+ ext4_normal_get_block_write, wbc);
else
- return block_write_full_page(page, ext4_get_block, wbc);
+ return block_write_full_page(page,
+ ext4_normal_get_block_write,
+ wbc);
}
-
static int ext4_normal_writepage(struct page *page,
struct writeback_control *wbc)
{
loff_t len;
J_ASSERT(PageLocked(page));
- J_ASSERT(page_has_buffers(page));
if (page->index == size >> PAGE_CACHE_SHIFT)
len = size & ~PAGE_CACHE_MASK;
else
len = PAGE_CACHE_SIZE;
- BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
- ext4_bh_unmapped_or_delay));
+
+ if (page_has_buffers(page)) {
+ /* if page has buffers it should all be mapped
+ * and allocated. If there are not buffers attached
+ * to the page we know the page is dirty but it lost
+ * buffers. That means that at some moment in time
+ * after write_begin() / write_end() has been called
+ * all buffers have been clean and thus they must have been
+ * written at least once. So they are all mapped and we can
+ * happily proceed with mapping them and writing the page.
+ */
+ BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
+ ext4_bh_unmapped_or_delay));
+ }
if (!ext4_journal_current_handle())
return __ext4_normal_writepage(page, wbc);
int ret = 0;
int err;
- ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, ext4_get_block);
+ ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
+ ext4_normal_get_block_write);
if (ret != 0)
goto out_unlock;
loff_t len;
J_ASSERT(PageLocked(page));
- J_ASSERT(page_has_buffers(page));
if (page->index == size >> PAGE_CACHE_SHIFT)
len = size & ~PAGE_CACHE_MASK;
else
len = PAGE_CACHE_SIZE;
- BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
- ext4_bh_unmapped_or_delay));
+
+ if (page_has_buffers(page)) {
+ /* if page has buffers it should all be mapped
+ * and allocated. If there are not buffers attached
+ * to the page we know the page is dirty but it lost
+ * buffers. That means that at some moment in time
+ * after write_begin() / write_end() has been called
+ * all buffers have been clean and thus they must have been
+ * written at least once. So they are all mapped and we can
+ * happily proceed with mapping them and writing the page.
+ */
+ BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL,
+ ext4_bh_unmapped_or_delay));
+ }
if (ext4_journal_current_handle())
goto no_write;
* really know unless we go poke around in the buffer_heads.
* But block_write_full_page will do the right thing.
*/
- return block_write_full_page(page, ext4_get_block, wbc);
+ return block_write_full_page(page,
+ ext4_normal_get_block_write,
+ wbc);
}
no_write:
redirty_page_for_writepage(wbc, page);
}
static const struct address_space_operations ext4_ordered_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_normal_writepage,
- .sync_page = block_sync_page,
- .write_begin = ext4_write_begin,
- .write_end = ext4_ordered_write_end,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_invalidatepage,
- .releasepage = ext4_releasepage,
- .direct_IO = ext4_direct_IO,
- .migratepage = buffer_migrate_page,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_normal_writepage,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_write_begin,
+ .write_end = ext4_ordered_write_end,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
};
static const struct address_space_operations ext4_writeback_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_normal_writepage,
- .sync_page = block_sync_page,
- .write_begin = ext4_write_begin,
- .write_end = ext4_writeback_write_end,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_invalidatepage,
- .releasepage = ext4_releasepage,
- .direct_IO = ext4_direct_IO,
- .migratepage = buffer_migrate_page,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_normal_writepage,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_write_begin,
+ .write_end = ext4_writeback_write_end,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
};
static const struct address_space_operations ext4_journalled_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_journalled_writepage,
- .sync_page = block_sync_page,
- .write_begin = ext4_write_begin,
- .write_end = ext4_journalled_write_end,
- .set_page_dirty = ext4_journalled_set_page_dirty,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_invalidatepage,
- .releasepage = ext4_releasepage,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_journalled_writepage,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_write_begin,
+ .write_end = ext4_journalled_write_end,
+ .set_page_dirty = ext4_journalled_set_page_dirty,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .is_partially_uptodate = block_is_partially_uptodate,
};
static const struct address_space_operations ext4_da_aops = {
- .readpage = ext4_readpage,
- .readpages = ext4_readpages,
- .writepage = ext4_da_writepage,
- .writepages = ext4_da_writepages,
- .sync_page = block_sync_page,
- .write_begin = ext4_da_write_begin,
- .write_end = ext4_da_write_end,
- .bmap = ext4_bmap,
- .invalidatepage = ext4_da_invalidatepage,
- .releasepage = ext4_releasepage,
- .direct_IO = ext4_direct_IO,
- .migratepage = buffer_migrate_page,
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_da_writepage,
+ .writepages = ext4_da_writepages,
+ .sync_page = block_sync_page,
+ .write_begin = ext4_da_write_begin,
+ .write_end = ext4_da_write_end,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_da_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+ .is_partially_uptodate = block_is_partially_uptodate,
};
void ext4_set_aops(struct inode *inode)
{
- if (ext4_should_order_data(inode))
+ if (ext4_should_order_data(inode) &&
+ test_opt(inode->i_sb, DELALLOC))
+ inode->i_mapping->a_ops = &ext4_da_aops;
+ else if (ext4_should_order_data(inode))
inode->i_mapping->a_ops = &ext4_ordered_aops;
else if (ext4_should_writeback_data(inode) &&
test_opt(inode->i_sb, DELALLOC))
if (ext4_orphan_add(handle, inode))
goto out_stop;
+ /*
+ * From here we block out all ext4_get_block() callers who want to
+ * modify the block allocation tree.
+ */
+ down_write(&ei->i_data_sem);
/*
* The orphan list entry will now protect us from any crash which
* occurs before the truncate completes, so it is now safe to propagate
*/
ei->i_disksize = inode->i_size;
- /*
- * From here we block out all ext4_get_block() callers who want to
- * modify the block allocation tree.
- */
- down_write(&ei->i_data_sem);
-
if (n == 1) { /* direct blocks */
ext4_free_data(handle, inode, NULL, i_data+offsets[0],
i_data + EXT4_NDIR_BLOCKS);
}
if (!buffer_uptodate(bh)) {
lock_buffer(bh);
+
+ /*
+ * If the buffer has the write error flag, we have failed
+ * to write out another inode in the same block. In this
+ * case, we don't have to read the block because we may
+ * read the old inode data successfully.
+ */
+ if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
+ set_buffer_uptodate(bh);
+
if (buffer_uptodate(bh)) {
/* someone brought it uptodate while we waited */
unlock_buffer(bh);
return error;
}
+int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
+ struct kstat *stat)
+{
+ struct inode *inode;
+ unsigned long delalloc_blocks;
+
+ inode = dentry->d_inode;
+ generic_fillattr(inode, stat);
+
+ /*
+ * We can't update i_blocks if the block allocation is delayed
+ * otherwise in the case of system crash before the real block
+ * allocation is done, we will have i_blocks inconsistent with
+ * on-disk file blocks.
+ * We always keep i_blocks updated together with real
+ * allocation. But to not confuse with user, stat
+ * will return the blocks that include the delayed allocation
+ * blocks for this file.
+ */
+ spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
+ delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+ spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+
+ stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9;
+ return 0;
+}
/*
* How many blocks doth make a writepage()?