}
truncate_inode_pages_final(&inode->i_data);
- WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count));
goto no_delete;
}
ext4_begin_ordered_truncate(inode, 0);
truncate_inode_pages_final(&inode->i_data);
- WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count));
-
/*
* Protect us against freezing - iput() caller didn't have to have any
* protection against it
* Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
* based files
*
- * On success, it returns the number of blocks being mapped or allocated.
- * if create==0 and the blocks are pre-allocated and unwritten block,
- * the result buffer head is unmapped. If the create ==1, it will make sure
- * the buffer head is mapped.
+ * On success, it returns the number of blocks being mapped or allocated. if
+ * create==0 and the blocks are pre-allocated and unwritten, the resulting @map
+ * is marked as unwritten. If the create == 1, it will mark @map as mapped.
*
* It returns 0 if plain look up failed (blocks have not been allocated), in
- * that case, buffer head is unmapped
+ * that case, @map is returned as unmapped but we still do fill map->m_len to
+ * indicate the length of a hole starting at map->m_lblk.
*
* It returns the error in case of allocation failure.
*/
retval = map->m_len;
map->m_len = retval;
} else if (ext4_es_is_delayed(&es) || ext4_es_is_hole(&es)) {
+ map->m_pblk = 0;
+ retval = es.es_len - (map->m_lblk - es.es_lblk);
+ if (retval > map->m_len)
+ retval = map->m_len;
+ map->m_len = retval;
retval = 0;
} else {
BUG_ON(1);
cmpxchg(&bh->b_state, old_state, new_state) != old_state));
}
-/* Maximum number of blocks we map for direct IO at once. */
-#define DIO_MAX_BLOCKS 4096
-
static int _ext4_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh, int flags)
{
- handle_t *handle = ext4_journal_current_handle();
struct ext4_map_blocks map;
- int ret = 0, started = 0;
- int dio_credits;
+ int ret = 0;
if (ext4_has_inline_data(inode))
return -ERANGE;
map.m_lblk = iblock;
map.m_len = bh->b_size >> inode->i_blkbits;
- if (flags && !handle) {
- /* Direct IO write... */
- if (map.m_len > DIO_MAX_BLOCKS)
- map.m_len = DIO_MAX_BLOCKS;
- dio_credits = ext4_chunk_trans_blocks(inode, map.m_len);
- handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS,
- dio_credits);
- if (IS_ERR(handle)) {
- ret = PTR_ERR(handle);
- return ret;
- }
- started = 1;
- }
-
- ret = ext4_map_blocks(handle, inode, &map, flags);
+ ret = ext4_map_blocks(ext4_journal_current_handle(), inode, &map,
+ flags);
if (ret > 0) {
- ext4_io_end_t *io_end = ext4_inode_aio(inode);
-
map_bh(bh, inode->i_sb, map.m_pblk);
ext4_update_bh_state(bh, map.m_flags);
- if (io_end && io_end->flag & EXT4_IO_END_UNWRITTEN)
- set_buffer_defer_completion(bh);
bh->b_size = inode->i_sb->s_blocksize * map.m_len;
ret = 0;
}
- if (started)
- ext4_journal_stop(handle);
return ret;
}
create ? EXT4_GET_BLOCKS_CREATE : 0);
}
+/*
+ * Get block function used when preparing for buffered write if we require
+ * creating an unwritten extent if blocks haven't been allocated. The extent
+ * will be converted to written after the IO is complete.
+ */
+int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ ext4_debug("ext4_get_block_unwritten: inode %lu, create flag %d\n",
+ inode->i_ino, create);
+ return _ext4_get_block(inode, iblock, bh_result,
+ EXT4_GET_BLOCKS_IO_CREATE_EXT);
+}
+
+/* Maximum number of blocks we map for direct IO at once. */
+#define DIO_MAX_BLOCKS 4096
+
+static handle_t *start_dio_trans(struct inode *inode,
+ struct buffer_head *bh_result)
+{
+ int dio_credits;
+
+ /* Trim mapping request to maximum we can map at once for DIO */
+ if (bh_result->b_size >> inode->i_blkbits > DIO_MAX_BLOCKS)
+ bh_result->b_size = DIO_MAX_BLOCKS << inode->i_blkbits;
+ dio_credits = ext4_chunk_trans_blocks(inode,
+ bh_result->b_size >> inode->i_blkbits);
+ return ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, dio_credits);
+}
+
+/* Get block function for DIO reads and writes to inodes without extents */
+int ext4_dio_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh, int create)
+{
+ handle_t *handle;
+ int ret;
+
+ /* We don't expect handle for direct IO */
+ WARN_ON_ONCE(ext4_journal_current_handle());
+
+ if (create) {
+ handle = start_dio_trans(inode, bh);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ }
+ ret = _ext4_get_block(inode, iblock, bh,
+ create ? EXT4_GET_BLOCKS_CREATE : 0);
+ if (create)
+ ext4_journal_stop(handle);
+ return ret;
+}
+
+/*
+ * Get block function for AIO DIO writes when we create unwritten extent if
+ * blocks are not allocated yet. The extent will be converted to written
+ * after IO is complete.
+ */
+static int ext4_dio_get_block_unwritten_async(struct inode *inode,
+ sector_t iblock, struct buffer_head *bh_result, int create)
+{
+ handle_t *handle;
+ int ret;
+
+ /* We don't expect handle for direct IO */
+ WARN_ON_ONCE(ext4_journal_current_handle());
+
+ handle = start_dio_trans(inode, bh_result);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = _ext4_get_block(inode, iblock, bh_result,
+ EXT4_GET_BLOCKS_IO_CREATE_EXT);
+ ext4_journal_stop(handle);
+
+ /*
+ * When doing DIO using unwritten extents, we need io_end to convert
+ * unwritten extents to written on IO completion. We allocate io_end
+ * once we spot unwritten extent and store it in b_private. Generic
+ * DIO code keeps b_private set and furthermore passes the value to
+ * our completion callback in 'private' argument.
+ */
+ if (!ret && buffer_unwritten(bh_result)) {
+ if (!bh_result->b_private) {
+ ext4_io_end_t *io_end;
+
+ io_end = ext4_init_io_end(inode, GFP_KERNEL);
+ if (!io_end)
+ return -ENOMEM;
+ bh_result->b_private = io_end;
+ ext4_set_io_unwritten_flag(inode, io_end);
+ }
+ set_buffer_defer_completion(bh_result);
+ }
+
+ return ret;
+}
+
+/*
+ * Get block function for non-AIO DIO writes when we create unwritten extent if
+ * blocks are not allocated yet. The extent will be converted to written
+ * after IO is complete from ext4_ext_direct_IO() function.
+ */
+static int ext4_dio_get_block_unwritten_sync(struct inode *inode,
+ sector_t iblock, struct buffer_head *bh_result, int create)
+{
+ handle_t *handle;
+ int ret;
+
+ /* We don't expect handle for direct IO */
+ WARN_ON_ONCE(ext4_journal_current_handle());
+
+ handle = start_dio_trans(inode, bh_result);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = _ext4_get_block(inode, iblock, bh_result,
+ EXT4_GET_BLOCKS_IO_CREATE_EXT);
+ ext4_journal_stop(handle);
+
+ /*
+ * Mark inode as having pending DIO writes to unwritten extents.
+ * ext4_ext_direct_IO() checks this flag and converts extents to
+ * written.
+ */
+ if (!ret && buffer_unwritten(bh_result))
+ ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
+
+ return ret;
+}
+
+static int ext4_dio_get_block_overwrite(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ int ret;
+
+ ext4_debug("ext4_dio_get_block_overwrite: inode %lu, create flag %d\n",
+ inode->i_ino, create);
+ /* We don't expect handle for direct IO */
+ WARN_ON_ONCE(ext4_journal_current_handle());
+
+ ret = _ext4_get_block(inode, iblock, bh_result, 0);
+ /*
+ * Blocks should have been preallocated! ext4_file_write_iter() checks
+ * that.
+ */
+ WARN_ON_ONCE(!buffer_mapped(bh_result) || buffer_unwritten(bh_result));
+
+ return ret;
+}
+
+
/*
* `handle' can be NULL if create is zero
*/
#ifdef CONFIG_EXT4_FS_ENCRYPTION
if (ext4_should_dioread_nolock(inode))
ret = ext4_block_write_begin(page, pos, len,
- ext4_get_block_write);
+ ext4_get_block_unwritten);
else
ret = ext4_block_write_begin(page, pos, len,
ext4_get_block);
#else
if (ext4_should_dioread_nolock(inode))
- ret = __block_write_begin(page, pos, len, ext4_get_block_write);
+ ret = __block_write_begin(page, pos, len,
+ ext4_get_block_unwritten);
else
ret = __block_write_begin(page, pos, len, ext4_get_block);
#endif
return try_to_free_buffers(page);
}
-/*
- * ext4_get_block used when preparing for a DIO write or buffer write.
- * We allocate an uinitialized extent if blocks haven't been allocated.
- * The extent will be converted to initialized after the IO is complete.
- */
-int ext4_get_block_write(struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create)
-{
- ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
- inode->i_ino, create);
- return _ext4_get_block(inode, iblock, bh_result,
- EXT4_GET_BLOCKS_IO_CREATE_EXT);
-}
-
-static int ext4_get_block_overwrite(struct inode *inode, sector_t iblock,
- struct buffer_head *bh_result, int create)
-{
- int ret;
-
- ext4_debug("ext4_get_block_overwrite: inode %lu, create flag %d\n",
- inode->i_ino, create);
- ret = _ext4_get_block(inode, iblock, bh_result, 0);
- /*
- * Blocks should have been preallocated! ext4_file_write_iter() checks
- * that.
- */
- WARN_ON_ONCE(!buffer_mapped(bh_result));
-
- return ret;
-}
-
#ifdef CONFIG_FS_DAX
int ext4_dax_mmap_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
WARN_ON_ONCE(ret == 0 && create);
if (ret > 0) {
map_bh(bh_result, inode->i_sb, map.m_pblk);
- bh_result->b_state = (bh_result->b_state & ~EXT4_MAP_FLAGS) |
- map.m_flags;
/*
* At least for now we have to clear BH_New so that DAX code
* doesn't attempt to zero blocks again in a racy way.
*/
- bh_result->b_state &= ~(1 << BH_New);
+ map.m_flags &= ~EXT4_MAP_NEW;
+ ext4_update_bh_state(bh_result, map.m_flags);
bh_result->b_size = map.m_len << inode->i_blkbits;
ret = 0;
}
static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
ssize_t size, void *private)
{
- ext4_io_end_t *io_end = iocb->private;
+ ext4_io_end_t *io_end = private;
/* if not async direct IO just return */
if (!io_end)
ext_debug("ext4_end_io_dio(): io_end 0x%p "
"for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
- iocb->private, io_end->inode->i_ino, iocb, offset,
- size);
+ io_end, io_end->inode->i_ino, iocb, offset, size);
- iocb->private = NULL;
io_end->offset = offset;
io_end->size = size;
ext4_put_io_end(io_end);
get_block_t *get_block_func = NULL;
int dio_flags = 0;
loff_t final_size = offset + count;
- ext4_io_end_t *io_end = NULL;
/* Use the old path for reads and writes beyond i_size. */
if (iov_iter_rw(iter) != WRITE || final_size > inode->i_size)
/*
* We could direct write to holes and fallocate.
*
- * Allocated blocks to fill the hole are marked as
- * unwritten to prevent parallel buffered read to expose
- * the stale data before DIO complete the data IO.
+ * Allocated blocks to fill the hole are marked as unwritten to prevent
+ * parallel buffered read to expose the stale data before DIO complete
+ * the data IO.
*
- * As to previously fallocated extents, ext4 get_block will
- * just simply mark the buffer mapped but still keep the
- * extents unwritten.
+ * As to previously fallocated extents, ext4 get_block will just simply
+ * mark the buffer mapped but still keep the extents unwritten.
*
- * For non AIO case, we will convert those unwritten extents
- * to written after return back from blockdev_direct_IO.
+ * For non AIO case, we will convert those unwritten extents to written
+ * after return back from blockdev_direct_IO. That way we save us from
+ * allocating io_end structure and also the overhead of offloading
+ * the extent convertion to a workqueue.
*
* For async DIO, the conversion needs to be deferred when the
* IO is completed. The ext4 end_io callback function will be
* case, we allocate an io_end structure to hook to the iocb.
*/
iocb->private = NULL;
- if (overwrite) {
- get_block_func = ext4_get_block_overwrite;
+ if (overwrite)
+ get_block_func = ext4_dio_get_block_overwrite;
+ else if (is_sync_kiocb(iocb)) {
+ get_block_func = ext4_dio_get_block_unwritten_sync;
+ dio_flags = DIO_LOCKING;
} else {
- ext4_inode_aio_set(inode, NULL);
- if (!is_sync_kiocb(iocb)) {
- io_end = ext4_init_io_end(inode, GFP_NOFS);
- if (!io_end) {
- ret = -ENOMEM;
- goto retake_lock;
- }
- /*
- * Grab reference for DIO. Will be dropped in
- * ext4_end_io_dio()
- */
- iocb->private = ext4_get_io_end(io_end);
- /*
- * we save the io structure for current async direct
- * IO, so that later ext4_map_blocks() could flag the
- * io structure whether there is a unwritten extents
- * needs to be converted when IO is completed.
- */
- ext4_inode_aio_set(inode, io_end);
- }
- get_block_func = ext4_get_block_write;
+ get_block_func = ext4_dio_get_block_unwritten_async;
dio_flags = DIO_LOCKING;
}
#ifdef CONFIG_EXT4_FS_ENCRYPTION
get_block_func,
ext4_end_io_dio, NULL, dio_flags);
- /*
- * Put our reference to io_end. This can free the io_end structure e.g.
- * in sync IO case or in case of error. It can even perform extent
- * conversion if all bios we submitted finished before we got here.
- * Note that in that case iocb->private can be already set to NULL
- * here.
- */
- if (io_end) {
- ext4_inode_aio_set(inode, NULL);
- ext4_put_io_end(io_end);
- /*
- * When no IO was submitted ext4_end_io_dio() was not
- * called so we have to put iocb's reference.
- */
- if (ret <= 0 && ret != -EIOCBQUEUED && iocb->private) {
- WARN_ON(iocb->private != io_end);
- WARN_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
- ext4_put_io_end(io_end);
- iocb->private = NULL;
- }
- }
if (ret > 0 && !overwrite && ext4_test_inode_state(inode,
EXT4_STATE_DIO_UNWRITTEN)) {
int err;
ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
}
-retake_lock:
if (iov_iter_rw(iter) == WRITE)
inode_dio_end(inode);
/* take i_mutex locking again if we do a ovewrite dio */
might_sleep();
trace_ext4_mark_inode_dirty(inode, _RET_IP_);
err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (err)
+ return err;
if (ext4_handle_valid(handle) &&
EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
!ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
}
}
}
- if (!err)
- err = ext4_mark_iloc_dirty(handle, inode, &iloc);
- return err;
+ return ext4_mark_iloc_dirty(handle, inode, &iloc);
}
/*
unlock_page(page);
/* OK, we need to fill the hole... */
if (ext4_should_dioread_nolock(inode))
- get_block = ext4_get_block_write;
+ get_block = ext4_get_block_unwritten;
else
get_block = ext4_get_block;
retry_alloc:
return err;
}
+
+/*
+ * Find the first extent at or after @lblk in an inode that is not a hole.
+ * Search for @map_len blocks at most. The extent is returned in @result.
+ *
+ * The function returns 1 if we found an extent. The function returns 0 in
+ * case there is no extent at or after @lblk and in that case also sets
+ * @result->es_len to 0. In case of error, the error code is returned.
+ */
+int ext4_get_next_extent(struct inode *inode, ext4_lblk_t lblk,
+ unsigned int map_len, struct extent_status *result)
+{
+ struct ext4_map_blocks map;
+ struct extent_status es = {};
+ int ret;
+
+ map.m_lblk = lblk;
+ map.m_len = map_len;
+
+ /*
+ * For non-extent based files this loop may iterate several times since
+ * we do not determine full hole size.
+ */
+ while (map.m_len > 0) {
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+ if (ret < 0)
+ return ret;
+ /* There's extent covering m_lblk? Just return it. */
+ if (ret > 0) {
+ int status;
+
+ ext4_es_store_pblock(result, map.m_pblk);
+ result->es_lblk = map.m_lblk;
+ result->es_len = map.m_len;
+ if (map.m_flags & EXT4_MAP_UNWRITTEN)
+ status = EXTENT_STATUS_UNWRITTEN;
+ else
+ status = EXTENT_STATUS_WRITTEN;
+ ext4_es_store_status(result, status);
+ return 1;
+ }
+ ext4_es_find_delayed_extent_range(inode, map.m_lblk,
+ map.m_lblk + map.m_len - 1,
+ &es);
+ /* Is delalloc data before next block in extent tree? */
+ if (es.es_len && es.es_lblk < map.m_lblk + map.m_len) {
+ ext4_lblk_t offset = 0;
+
+ if (es.es_lblk < lblk)
+ offset = lblk - es.es_lblk;
+ result->es_lblk = es.es_lblk + offset;
+ ext4_es_store_pblock(result,
+ ext4_es_pblock(&es) + offset);
+ result->es_len = es.es_len - offset;
+ ext4_es_store_status(result, ext4_es_status(&es));
+
+ return 1;
+ }
+ /* There's a hole at m_lblk, advance us after it */
+ map.m_lblk += map.m_len;
+ map_len -= map.m_len;
+ map.m_len = map_len;
+ cond_resched();
+ }
+ result->es_len = 0;
+ return 0;
+}
projects / cascardo / linux.git / blobdiff