}
/*
- * This function is called by ext4_evict_inode() to make sure there is
- * no more pending I/O completion work left to do.
+ * Print an buffer I/O error compatible with the fs/buffer.c. This
+ * provides compatibility with dmesg scrapers that look for a specific
+ * buffer I/O error message. We really need a unified error reporting
+ * structure to userspace ala Digital Unix's uerf system, but it's
+ * probably not going to happen in my lifetime, due to LKML politics...
*/
-void ext4_ioend_shutdown(struct inode *inode)
+static void buffer_io_error(struct buffer_head *bh)
+{
+ char b[BDEVNAME_SIZE];
+ printk(KERN_ERR "Buffer I/O error on device %s, logical block %llu\n",
+ bdevname(bh->b_bdev, b),
+ (unsigned long long)bh->b_blocknr);
+}
+
+static void ext4_finish_bio(struct bio *bio)
{
- wait_queue_head_t *wq = ext4_ioend_wq(inode);
+ int i;
+ int error = !test_bit(BIO_UPTODATE, &bio->bi_flags);
- wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_ioend_count) == 0));
- /*
- * We need to make sure the work structure is finished being
- * used before we let the inode get destroyed.
- */
- if (work_pending(&EXT4_I(inode)->i_unwritten_work))
- cancel_work_sync(&EXT4_I(inode)->i_unwritten_work);
+ for (i = 0; i < bio->bi_vcnt; i++) {
+ struct bio_vec *bvec = &bio->bi_io_vec[i];
+ struct page *page = bvec->bv_page;
+ struct buffer_head *bh, *head;
+ unsigned bio_start = bvec->bv_offset;
+ unsigned bio_end = bio_start + bvec->bv_len;
+ unsigned under_io = 0;
+ unsigned long flags;
+
+ if (!page)
+ continue;
+
+ if (error) {
+ SetPageError(page);
+ set_bit(AS_EIO, &page->mapping->flags);
+ }
+ bh = head = page_buffers(page);
+ /*
+ * We check all buffers in the page under BH_Uptodate_Lock
+ * to avoid races with other end io clearing async_write flags
+ */
+ local_irq_save(flags);
+ bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
+ do {
+ if (bh_offset(bh) < bio_start ||
+ bh_offset(bh) + bh->b_size > bio_end) {
+ if (buffer_async_write(bh))
+ under_io++;
+ continue;
+ }
+ clear_buffer_async_write(bh);
+ if (error)
+ buffer_io_error(bh);
+ } while ((bh = bh->b_this_page) != head);
+ bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
+ local_irq_restore(flags);
+ if (!under_io)
+ end_page_writeback(page);
+ }
}
-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);
+ struct bio *bio, *next_bio;
- 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);
+ BUG_ON(!list_empty(&io_end->list));
+ BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
+ WARN_ON(io_end->handle);
+
+ if (atomic_dec_and_test(&EXT4_I(io_end->inode)->i_ioend_count))
+ wake_up_all(ext4_ioend_wq(io_end->inode));
+
+ for (bio = io_end->bio; bio; bio = next_bio) {
+ next_bio = bio->bi_private;
+ ext4_finish_bio(bio);
+ bio_put(bio);
+ }
+ 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);
}
-/* check a range of space and convert unwritten extents to written. */
+static void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
+{
+ struct inode *inode = io_end->inode;
+
+ 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. Note that
+ * we are protected from truncate touching same part of extent tree by the
+ * fact that truncate code waits for all DIO to finish (thus exclusion from
+ * direct IO is achieved) and also waits for PageWriteback bits. Thus we
+ * cannot get to ext4_ext_truncate() before all IOs overlapping that range are
+ * completed (happens from ext4_free_ioend()).
+ */
static int ext4_end_io(ext4_io_end_t *io)
{
struct inode *inode = io->inode;
loff_t offset = io->offset;
ssize_t size = io->size;
+ handle_t *handle = io->handle;
int ret = 0;
ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p,"
"list->prev 0x%p\n",
io, inode->i_ino, io->list.next, io->list.prev);
- ret = ext4_convert_unwritten_extents(inode, offset, size);
+ io->handle = NULL; /* Following call will use up the handle */
+ ret = ext4_convert_unwritten_extents(handle, inode, offset, size);
if (ret < 0) {
ext4_msg(inode->i_sb, KERN_EMERG,
"failed to 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;
}
-static void dump_completed_IO(struct inode *inode)
+static void dump_completed_IO(struct inode *inode, struct list_head *head)
{
#ifdef EXT4FS_DEBUG
struct list_head *cur, *before, *after;
ext4_io_end_t *io, *io0, *io1;
- if (list_empty(&EXT4_I(inode)->i_completed_io_list)) {
- ext4_debug("inode %lu completed_io list is empty\n",
- inode->i_ino);
+ if (list_empty(head))
return;
- }
- ext4_debug("Dump inode %lu completed_io list\n", inode->i_ino);
- list_for_each_entry(io, &EXT4_I(inode)->i_completed_io_list, list) {
+ ext4_debug("Dump inode %lu completed io list\n", inode->i_ino);
+ list_for_each_entry(io, head, list) {
cur = &io->list;
before = cur->prev;
io0 = container_of(before, ext4_io_end_t, list);
}
/* 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;
unsigned long flags;
BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN));
- wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
-
spin_lock_irqsave(&ei->i_completed_io_lock, flags);
- if (list_empty(&ei->i_completed_io_list))
- queue_work(wq, &ei->i_unwritten_work);
- list_add_tail(&io_end->list, &ei->i_completed_io_list);
+ if (io_end->handle) {
+ wq = EXT4_SB(io_end->inode->i_sb)->rsv_conversion_wq;
+ if (list_empty(&ei->i_rsv_conversion_list))
+ queue_work(wq, &ei->i_rsv_conversion_work);
+ list_add_tail(&io_end->list, &ei->i_rsv_conversion_list);
+ } else {
+ wq = EXT4_SB(io_end->inode->i_sb)->unrsv_conversion_wq;
+ if (list_empty(&ei->i_unrsv_conversion_list))
+ queue_work(wq, &ei->i_unrsv_conversion_work);
+ list_add_tail(&io_end->list, &ei->i_unrsv_conversion_list);
+ }
spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
}
-static int ext4_do_flush_completed_IO(struct inode *inode)
+static int ext4_do_flush_completed_IO(struct inode *inode,
+ struct list_head *head)
{
ext4_io_end_t *io;
struct list_head unwritten;
int err, ret = 0;
spin_lock_irqsave(&ei->i_completed_io_lock, flags);
- dump_completed_IO(inode);
- list_replace_init(&ei->i_completed_io_list, &unwritten);
+ dump_completed_IO(inode, head);
+ list_replace_init(head, &unwritten);
spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
while (!list_empty(&unwritten)) {
err = ext4_end_io(io);
if (unlikely(!ret && err))
ret = err;
- io->flag &= ~EXT4_IO_END_UNWRITTEN;
- ext4_free_io_end(io);
}
return ret;
}
/*
- * work on completed aio dio IO, to convert unwritten extents to extents
+ * work on completed IO, to convert unwritten extents to extents
*/
-void ext4_end_io_work(struct work_struct *work)
+void ext4_end_io_rsv_work(struct work_struct *work)
{
struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info,
- i_unwritten_work);
- ext4_do_flush_completed_IO(&ei->vfs_inode);
+ i_rsv_conversion_work);
+ ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list);
}
-int ext4_flush_unwritten_io(struct inode *inode)
+void ext4_end_io_unrsv_work(struct work_struct *work)
{
- int ret;
- WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex) &&
- !(inode->i_state & I_FREEING));
- ret = ext4_do_flush_completed_IO(inode);
- ext4_unwritten_wait(inode);
- return ret;
+ struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info,
+ i_unrsv_conversion_work);
+ ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_unrsv_conversion_list);
}
ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags)
atomic_inc(&EXT4_I(inode)->i_ioend_count);
io->inode = inode;
INIT_LIST_HEAD(&io->list);
+ atomic_set(&io->count, 1);
}
return io;
}
-/*
- * Print an buffer I/O error compatible with the fs/buffer.c. This
- * provides compatibility with dmesg scrapers that look for a specific
- * buffer I/O error message. We really need a unified error reporting
- * structure to userspace ala Digital Unix's uerf system, but it's
- * probably not going to happen in my lifetime, due to LKML politics...
- */
-static void buffer_io_error(struct buffer_head *bh)
+void ext4_put_io_end_defer(ext4_io_end_t *io_end)
{
- char b[BDEVNAME_SIZE];
- printk(KERN_ERR "Buffer I/O error on device %s, logical block %llu\n",
- bdevname(bh->b_bdev, b),
- (unsigned long long)bh->b_blocknr);
+ 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->handle,
+ io_end->inode, io_end->offset,
+ io_end->size);
+ io_end->handle = NULL;
+ 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;
+}
+
+/* BIO completion function for page writeback */
static void ext4_end_bio(struct bio *bio, int error)
{
ext4_io_end_t *io_end = bio->bi_private;
- struct inode *inode;
- int i;
- int blocksize;
sector_t bi_sector = bio->bi_sector;
BUG_ON(!io_end);
- inode = io_end->inode;
- blocksize = 1 << inode->i_blkbits;
- bio->bi_private = NULL;
bio->bi_end_io = NULL;
if (test_bit(BIO_UPTODATE, &bio->bi_flags))
error = 0;
- for (i = 0; i < bio->bi_vcnt; i++) {
- struct bio_vec *bvec = &bio->bi_io_vec[i];
- struct page *page = bvec->bv_page;
- struct buffer_head *bh, *head;
- unsigned bio_start = bvec->bv_offset;
- unsigned bio_end = bio_start + bvec->bv_len;
- unsigned under_io = 0;
- unsigned long flags;
-
- if (!page)
- continue;
-
- if (error) {
- SetPageError(page);
- set_bit(AS_EIO, &page->mapping->flags);
- }
- bh = head = page_buffers(page);
- /*
- * We check all buffers in the page under BH_Uptodate_Lock
- * to avoid races with other end io clearing async_write flags
- */
- local_irq_save(flags);
- bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
- do {
- if (bh_offset(bh) < bio_start ||
- bh_offset(bh) + blocksize > bio_end) {
- if (buffer_async_write(bh))
- under_io++;
- continue;
- }
- clear_buffer_async_write(bh);
- if (error)
- buffer_io_error(bh);
- } while ((bh = bh->b_this_page) != head);
- bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
- local_irq_restore(flags);
- if (!under_io)
- end_page_writeback(page);
- }
- bio_put(bio);
if (error) {
- io_end->flag |= EXT4_IO_END_ERROR;
+ struct inode *inode = io_end->inode;
+
ext4_warning(inode->i_sb, "I/O error writing to inode %lu "
"(offset %llu size %ld starting block %llu)",
inode->i_ino,
bi_sector >> (inode->i_blkbits - 9));
}
- if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
- ext4_free_io_end(io_end);
- return;
+ if (io_end->flag & EXT4_IO_END_UNWRITTEN) {
+ /*
+ * Link bio into list hanging from io_end. We have to do it
+ * atomically as bio completions can be racing against each
+ * other.
+ */
+ bio->bi_private = xchg(&io_end->bio, bio);
+ ext4_put_io_end_defer(io_end);
+ } else {
+ /*
+ * Drop io_end reference early. Inode can get freed once
+ * we finish the bio.
+ */
+ ext4_put_io_end_defer(io_end);
+ ext4_finish_bio(bio);
+ bio_put(bio);
}
-
- ext4_add_complete_io(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));
+ if (!bio)
+ return -ENOMEM;
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);
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;
int ret;
if (io->io_bio && bh->b_blocknr != io->io_next_block) {
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;
}
- 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->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;
+ io->io_next_block++;
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
projects / ~andy / linux / blobdiff