ssize_t size; /* size of the extent */
struct kiocb *iocb; /* iocb struct for AIO */
int result; /* error value for AIO */
+ atomic_t count; /* reference counter */
} ext4_io_end_t;
struct ext4_io_submit {
/* page-io.c */
extern int __init ext4_init_pageio(void);
-extern void ext4_add_complete_io(ext4_io_end_t *io_end);
extern void ext4_exit_pageio(void);
extern void ext4_ioend_shutdown(struct inode *);
-extern void ext4_free_io_end(ext4_io_end_t *io);
extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
+extern ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end);
+extern int ext4_put_io_end(ext4_io_end_t *io_end);
+extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
+extern void ext4_io_submit_init(struct ext4_io_submit *io,
+ struct writeback_control *wbc);
extern void ext4_end_io_work(struct work_struct *work);
extern void ext4_io_submit(struct ext4_io_submit *io);
extern int ext4_bio_write_page(struct ext4_io_submit *io,
* Delayed allocation stuff
*/
+static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd);
+
/*
* mpage_da_submit_io - walks through extent of pages and try to write
* them with writepage() call back
struct ext4_io_submit io_submit;
BUG_ON(mpd->next_page <= mpd->first_page);
- memset(&io_submit, 0, sizeof(io_submit));
+ ext4_io_submit_init(&io_submit, mpd->wbc);
+ io_submit.io_end = ext4_init_io_end(inode, GFP_NOFS);
+ if (!io_submit.io_end) {
+ ext4_da_block_invalidatepages(mpd);
+ return -ENOMEM;
+ }
/*
* We need to start from the first_page to the next_page - 1
* to make sure we also write the mapped dirty buffer_heads.
pagevec_release(&pvec);
}
ext4_io_submit(&io_submit);
+ /* Drop io_end reference we got from init */
+ ext4_put_io_end_defer(io_submit.io_end);
return ret;
}
*/
return __ext4_journalled_writepage(page, len);
- memset(&io_submit, 0, sizeof(io_submit));
+ ext4_io_submit_init(&io_submit, wbc);
+ io_submit.io_end = ext4_init_io_end(inode, GFP_NOFS);
+ if (!io_submit.io_end) {
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return -ENOMEM;
+ }
ret = ext4_bio_write_page(&io_submit, page, len, wbc);
ext4_io_submit(&io_submit);
+ /* Drop io_end reference we got from init */
+ ext4_put_io_end_defer(io_submit.io_end);
return ret;
}
struct inode *inode = file_inode(iocb->ki_filp);
ext4_io_end_t *io_end = iocb->private;
- /* if not async direct IO or dio with 0 bytes write, just return */
- if (!io_end || !size)
- goto out;
+ /* if not async direct IO just return */
+ if (!io_end) {
+ inode_dio_done(inode);
+ if (is_async)
+ aio_complete(iocb, ret, 0);
+ return;
+ }
ext_debug("ext4_end_io_dio(): io_end 0x%p "
"for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
size);
iocb->private = NULL;
-
- /* if not aio dio with unwritten extents, just free io and return */
- if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
- ext4_free_io_end(io_end);
-out:
- inode_dio_done(inode);
- if (is_async)
- aio_complete(iocb, ret, 0);
- return;
- }
-
io_end->offset = offset;
io_end->size = size;
if (is_async) {
io_end->iocb = iocb;
io_end->result = ret;
}
-
- ext4_add_complete_io(io_end);
+ ext4_put_io_end_defer(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 (rw != WRITE || final_size > inode->i_size)
iocb->private = NULL;
ext4_inode_aio_set(inode, NULL);
if (!is_sync_kiocb(iocb)) {
- ext4_io_end_t *io_end = ext4_init_io_end(inode, GFP_NOFS);
+ io_end = ext4_init_io_end(inode, GFP_NOFS);
if (!io_end) {
ret = -ENOMEM;
goto retake_lock;
}
io_end->flag |= EXT4_IO_END_DIRECT;
- iocb->private = io_end;
+ /*
+ * 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
NULL,
dio_flags);
- if (iocb->private)
- ext4_inode_aio_set(inode, NULL);
/*
- * The io_end structure takes a reference to the inode, that
- * structure needs to be destroyed and the reference to the
- * inode need to be dropped, when IO is complete, even with 0
- * byte write, or failed.
- *
- * In the successful AIO DIO case, the io_end structure will
- * be destroyed and the reference to the inode will be dropped
- * after the end_io call back function is called.
- *
- * In the case there is 0 byte write, or error case, since VFS
- * direct IO won't invoke the end_io call back function, we
- * need to free the end_io structure here.
+ * 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 (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) {
- ext4_free_io_end(iocb->private);
- iocb->private = NULL;
- } else if (ret > 0 && !overwrite && ext4_test_inode_state(inode,
+ 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);
+ WARN_ON(io_end->iocb);
+ /*
+ * Generic code already did inode_dio_done() so we
+ * have to clear EXT4_IO_END_DIRECT to not do it for
+ * the second time.
+ */
+ io_end->flag = 0;
+ ext4_put_io_end(io_end);
+ iocb->private = NULL;
+ }
+ }
+ if (ret > 0 && !overwrite && ext4_test_inode_state(inode,
EXT4_STATE_DIO_UNWRITTEN)) {
int err;
/*
cancel_work_sync(&EXT4_I(inode)->i_unwritten_work);
}
-void ext4_free_io_end(ext4_io_end_t *io)
+static void ext4_release_io_end(ext4_io_end_t *io_end)
{
- BUG_ON(!io);
- BUG_ON(!list_empty(&io->list));
- BUG_ON(io->flag & EXT4_IO_END_UNWRITTEN);
+ BUG_ON(!list_empty(&io_end->list));
+ BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
+
+ if (atomic_dec_and_test(&EXT4_I(io_end->inode)->i_ioend_count))
+ wake_up_all(ext4_ioend_wq(io_end->inode));
+ if (io_end->flag & EXT4_IO_END_DIRECT)
+ inode_dio_done(io_end->inode);
+ if (io_end->iocb)
+ aio_complete(io_end->iocb, io_end->result, 0);
+ kmem_cache_free(io_end_cachep, io_end);
+}
+
+static void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
+{
+ struct inode *inode = io_end->inode;
- if (atomic_dec_and_test(&EXT4_I(io->inode)->i_ioend_count))
- wake_up_all(ext4_ioend_wq(io->inode));
- kmem_cache_free(io_end_cachep, io);
+ io_end->flag &= ~EXT4_IO_END_UNWRITTEN;
+ /* Wake up anyone waiting on unwritten extent conversion */
+ if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
+ wake_up_all(ext4_ioend_wq(inode));
}
/* check a range of space and convert unwritten extents to written. */
"(inode %lu, offset %llu, size %zd, error %d)",
inode->i_ino, offset, size, ret);
}
- /* Wake up anyone waiting on unwritten extent conversion */
- if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten))
- wake_up_all(ext4_ioend_wq(inode));
- if (io->flag & EXT4_IO_END_DIRECT)
- inode_dio_done(inode);
- if (io->iocb)
- aio_complete(io->iocb, io->result, 0);
+ ext4_clear_io_unwritten_flag(io);
+ ext4_release_io_end(io);
return ret;
}
}
/* Add the io_end to per-inode completed end_io list. */
-void ext4_add_complete_io(ext4_io_end_t *io_end)
+static void ext4_add_complete_io(ext4_io_end_t *io_end)
{
struct ext4_inode_info *ei = EXT4_I(io_end->inode);
struct workqueue_struct *wq;
err = ext4_end_io(io);
if (unlikely(!ret && err))
ret = err;
- io->flag &= ~EXT4_IO_END_UNWRITTEN;
- ext4_free_io_end(io);
}
return ret;
}
atomic_inc(&EXT4_I(inode)->i_ioend_count);
io->inode = inode;
INIT_LIST_HEAD(&io->list);
+ atomic_set(&io->count, 1);
}
return io;
}
+void ext4_put_io_end_defer(ext4_io_end_t *io_end)
+{
+ if (atomic_dec_and_test(&io_end->count)) {
+ if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) || !io_end->size) {
+ ext4_release_io_end(io_end);
+ return;
+ }
+ ext4_add_complete_io(io_end);
+ }
+}
+
+int ext4_put_io_end(ext4_io_end_t *io_end)
+{
+ int err = 0;
+
+ if (atomic_dec_and_test(&io_end->count)) {
+ if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
+ err = ext4_convert_unwritten_extents(io_end->inode,
+ io_end->offset, io_end->size);
+ ext4_clear_io_unwritten_flag(io_end);
+ }
+ ext4_release_io_end(io_end);
+ }
+ return err;
+}
+
+ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end)
+{
+ atomic_inc(&io_end->count);
+ return io_end;
+}
+
/*
* Print an buffer I/O error compatible with the fs/buffer.c. This
* provides compatibility with dmesg scrapers that look for a specific
bi_sector >> (inode->i_blkbits - 9));
}
- if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
- ext4_free_io_end(io_end);
- return;
- }
-
- ext4_add_complete_io(io_end);
+ ext4_put_io_end_defer(io_end);
}
void ext4_io_submit(struct ext4_io_submit *io)
bio_put(io->io_bio);
}
io->io_bio = NULL;
- io->io_op = 0;
+}
+
+void ext4_io_submit_init(struct ext4_io_submit *io,
+ struct writeback_control *wbc)
+{
+ io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
+ io->io_bio = NULL;
io->io_end = NULL;
}
-static int io_submit_init(struct ext4_io_submit *io,
- struct inode *inode,
- struct writeback_control *wbc,
- struct buffer_head *bh)
+static int io_submit_init_bio(struct ext4_io_submit *io,
+ struct buffer_head *bh)
{
- ext4_io_end_t *io_end;
- struct page *page = bh->b_page;
int nvecs = bio_get_nr_vecs(bh->b_bdev);
struct bio *bio;
- io_end = ext4_init_io_end(inode, GFP_NOFS);
- if (!io_end)
- return -ENOMEM;
bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES));
bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
bio->bi_bdev = bh->b_bdev;
- bio->bi_private = io->io_end = io_end;
bio->bi_end_io = ext4_end_bio;
-
- io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh);
-
+ bio->bi_private = ext4_get_io_end(io->io_end);
+ if (!io->io_end->size)
+ io->io_end->offset = (bh->b_page->index << PAGE_CACHE_SHIFT)
+ + bh_offset(bh);
io->io_bio = bio;
- io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
io->io_next_block = bh->b_blocknr;
return 0;
}
static int io_submit_add_bh(struct ext4_io_submit *io,
struct inode *inode,
- struct writeback_control *wbc,
struct buffer_head *bh)
{
ext4_io_end_t *io_end;
ext4_io_submit(io);
}
if (io->io_bio == NULL) {
- ret = io_submit_init(io, inode, wbc, bh);
+ ret = io_submit_init_bio(io, bh);
if (ret)
return ret;
}
+ ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh));
+ if (ret != bh->b_size)
+ goto submit_and_retry;
io_end = io->io_end;
if (test_clear_buffer_uninit(bh))
ext4_set_io_unwritten_flag(inode, io_end);
- io->io_end->size += bh->b_size;
+ io_end->size += bh->b_size;
io->io_next_block++;
- ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh));
- if (ret != bh->b_size)
- goto submit_and_retry;
return 0;
}
do {
if (!buffer_async_write(bh))
continue;
- ret = io_submit_add_bh(io, inode, wbc, bh);
+ ret = io_submit_add_bh(io, inode, bh);
if (ret) {
/*
* We only get here on ENOMEM. Not much else