ext4: use bio layer instead of buffer layer in mpage_da_submit_io
Call the block I/O layer directly instad of going through the buffer layer. This should give us much better performance and scalability, as well as lowering our CPU utilization when doing buffered writeback. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o
parent
1de3e3df91
commit
bd2d0210cf
6 changed files with 489 additions and 109 deletions
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@ -4,7 +4,7 @@
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obj-$(CONFIG_EXT4_FS) += ext4.o
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ext4-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
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ext4-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o page-io.o \
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ioctl.o namei.o super.o symlink.o hash.o resize.o extents.o \
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ext4_jbd2.o migrate.o mballoc.o block_validity.o move_extent.o
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@ -168,7 +168,20 @@ struct mpage_da_data {
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int pages_written;
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int retval;
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};
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#define EXT4_IO_UNWRITTEN 0x1
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/*
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* Flags for ext4_io_end->flags
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*/
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#define EXT4_IO_END_UNWRITTEN 0x0001
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#define EXT4_IO_END_ERROR 0x0002
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struct ext4_io_page {
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struct page *p_page;
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int p_count;
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};
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#define MAX_IO_PAGES 128
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typedef struct ext4_io_end {
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struct list_head list; /* per-file finished IO list */
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struct inode *inode; /* file being written to */
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@ -179,8 +192,18 @@ typedef struct ext4_io_end {
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struct work_struct work; /* data work queue */
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struct kiocb *iocb; /* iocb struct for AIO */
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int result; /* error value for AIO */
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int num_io_pages;
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struct ext4_io_page *pages[MAX_IO_PAGES];
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} ext4_io_end_t;
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struct ext4_io_submit {
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int io_op;
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struct bio *io_bio;
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ext4_io_end_t *io_end;
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struct ext4_io_page *io_page;
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sector_t io_next_block;
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};
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/*
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* Special inodes numbers
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*/
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@ -2044,6 +2067,17 @@ extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
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__u64 start_orig, __u64 start_donor,
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__u64 len, __u64 *moved_len);
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/* page-io.c */
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extern int __init init_ext4_pageio(void);
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extern void exit_ext4_pageio(void);
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extern void ext4_free_io_end(ext4_io_end_t *io);
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extern ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags);
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extern int ext4_end_io_nolock(ext4_io_end_t *io);
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extern void ext4_io_submit(struct ext4_io_submit *io);
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extern int ext4_bio_write_page(struct ext4_io_submit *io,
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struct page *page,
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int len,
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struct writeback_control *wbc);
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/* BH_Uninit flag: blocks are allocated but uninitialized on disk */
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enum ext4_state_bits {
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@ -3202,7 +3202,7 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
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* completed
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*/
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if (io)
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io->flag = EXT4_IO_UNWRITTEN;
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io->flag = EXT4_IO_END_UNWRITTEN;
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else
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ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
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if (ext4_should_dioread_nolock(inode))
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@ -3494,7 +3494,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
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*/
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if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
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if (io)
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io->flag = EXT4_IO_UNWRITTEN;
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io->flag = EXT4_IO_END_UNWRITTEN;
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else
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ext4_set_inode_state(inode,
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EXT4_STATE_DIO_UNWRITTEN);
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118
fs/ext4/inode.c
118
fs/ext4/inode.c
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@ -2016,8 +2016,10 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd,
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struct buffer_head *bh, *page_bufs = NULL;
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int journal_data = ext4_should_journal_data(inode);
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sector_t pblock = 0, cur_logical = 0;
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struct ext4_io_submit io_submit;
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BUG_ON(mpd->next_page <= mpd->first_page);
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memset(&io_submit, 0, sizeof(io_submit));
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/*
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* We need to start from the first_page to the next_page - 1
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* to make sure we also write the mapped dirty buffer_heads.
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@ -2109,16 +2111,16 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd,
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/* mark the buffer_heads as dirty & uptodate */
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block_commit_write(page, 0, len);
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if (journal_data && PageChecked(page))
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/*
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* Delalloc doesn't support data journalling,
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* but eventually maybe we'll lift this
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* restriction.
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*/
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if (unlikely(journal_data && PageChecked(page)))
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err = __ext4_journalled_writepage(page, len);
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else if (buffer_uninit(page_bufs)) {
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ext4_set_bh_endio(page_bufs, inode);
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err = block_write_full_page_endio(page,
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noalloc_get_block_write,
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mpd->wbc, ext4_end_io_buffer_write);
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} else
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err = block_write_full_page(page,
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noalloc_get_block_write, mpd->wbc);
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else
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err = ext4_bio_write_page(&io_submit, page,
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len, mpd->wbc);
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if (!err)
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mpd->pages_written++;
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@ -2131,6 +2133,7 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd,
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}
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pagevec_release(&pvec);
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}
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ext4_io_submit(&io_submit);
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return ret;
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}
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@ -3426,15 +3429,6 @@ ext4_readpages(struct file *file, struct address_space *mapping,
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return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
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}
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static void ext4_free_io_end(ext4_io_end_t *io)
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{
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BUG_ON(!io);
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if (io->page)
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put_page(io->page);
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iput(io->inode);
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kfree(io);
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}
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static void ext4_invalidatepage_free_endio(struct page *page, unsigned long offset)
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{
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struct buffer_head *head, *bh;
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@ -3639,68 +3633,6 @@ static void dump_completed_IO(struct inode * inode)
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#endif
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}
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/*
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* check a range of space and convert unwritten extents to written.
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*/
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static int ext4_end_io_nolock(ext4_io_end_t *io)
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{
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struct inode *inode = io->inode;
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loff_t offset = io->offset;
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ssize_t size = io->size;
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int ret = 0;
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ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p,"
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"list->prev 0x%p\n",
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io, inode->i_ino, io->list.next, io->list.prev);
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if (list_empty(&io->list))
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return ret;
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if (io->flag != EXT4_IO_UNWRITTEN)
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return ret;
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ret = ext4_convert_unwritten_extents(inode, offset, size);
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if (ret < 0) {
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printk(KERN_EMERG "%s: failed to convert unwritten"
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"extents to written extents, error is %d"
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" io is still on inode %lu aio dio list\n",
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__func__, ret, inode->i_ino);
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return ret;
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}
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if (io->iocb)
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aio_complete(io->iocb, io->result, 0);
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/* clear the DIO AIO unwritten flag */
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io->flag = 0;
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return ret;
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}
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/*
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* work on completed aio dio IO, to convert unwritten extents to extents
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*/
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static void ext4_end_io_work(struct work_struct *work)
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{
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ext4_io_end_t *io = container_of(work, ext4_io_end_t, work);
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struct inode *inode = io->inode;
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struct ext4_inode_info *ei = EXT4_I(inode);
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unsigned long flags;
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int ret;
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mutex_lock(&inode->i_mutex);
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ret = ext4_end_io_nolock(io);
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if (ret < 0) {
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mutex_unlock(&inode->i_mutex);
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return;
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}
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spin_lock_irqsave(&ei->i_completed_io_lock, flags);
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if (!list_empty(&io->list))
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list_del_init(&io->list);
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spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
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mutex_unlock(&inode->i_mutex);
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ext4_free_io_end(io);
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}
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/*
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* This function is called from ext4_sync_file().
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*
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@ -3756,28 +3688,6 @@ int flush_completed_IO(struct inode *inode)
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return (ret2 < 0) ? ret2 : 0;
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}
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static ext4_io_end_t *ext4_init_io_end (struct inode *inode, gfp_t flags)
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{
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ext4_io_end_t *io = NULL;
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io = kmalloc(sizeof(*io), flags);
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if (io) {
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igrab(inode);
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io->inode = inode;
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io->flag = 0;
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io->offset = 0;
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io->size = 0;
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io->page = NULL;
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io->iocb = NULL;
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io->result = 0;
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INIT_WORK(&io->work, ext4_end_io_work);
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INIT_LIST_HEAD(&io->list);
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}
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return io;
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}
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static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
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ssize_t size, void *private, int ret,
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bool is_async)
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@ -3797,7 +3707,7 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
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size);
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/* if not aio dio with unwritten extents, just free io and return */
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if (io_end->flag != EXT4_IO_UNWRITTEN){
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if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
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ext4_free_io_end(io_end);
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iocb->private = NULL;
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out:
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@ -3842,7 +3752,7 @@ static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate)
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goto out;
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}
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io_end->flag = EXT4_IO_UNWRITTEN;
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io_end->flag = EXT4_IO_END_UNWRITTEN;
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inode = io_end->inode;
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/* Add the io_end to per-inode completed io list*/
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430
fs/ext4/page-io.c
Normal file
430
fs/ext4/page-io.c
Normal file
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@ -0,0 +1,430 @@
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/*
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* linux/fs/ext4/page-io.c
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*
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* This contains the new page_io functions for ext4
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*
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* Written by Theodore Ts'o, 2010.
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/time.h>
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#include <linux/jbd2.h>
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#include <linux/highuid.h>
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#include <linux/pagemap.h>
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#include <linux/quotaops.h>
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#include <linux/string.h>
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#include <linux/buffer_head.h>
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#include <linux/writeback.h>
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#include <linux/pagevec.h>
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#include <linux/mpage.h>
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#include <linux/namei.h>
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#include <linux/uio.h>
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#include <linux/bio.h>
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#include <linux/workqueue.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include "ext4_jbd2.h"
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#include "xattr.h"
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#include "acl.h"
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#include "ext4_extents.h"
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static struct kmem_cache *io_page_cachep, *io_end_cachep;
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int __init init_ext4_pageio(void)
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{
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io_page_cachep = KMEM_CACHE(ext4_io_page, SLAB_RECLAIM_ACCOUNT);
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if (io_page_cachep == NULL)
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return -ENOMEM;
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io_end_cachep = KMEM_CACHE(ext4_io_end, SLAB_RECLAIM_ACCOUNT);
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if (io_page_cachep == NULL) {
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kmem_cache_destroy(io_page_cachep);
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return -ENOMEM;
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}
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return 0;
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}
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void exit_ext4_pageio(void)
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{
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kmem_cache_destroy(io_end_cachep);
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kmem_cache_destroy(io_page_cachep);
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}
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void ext4_free_io_end(ext4_io_end_t *io)
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{
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int i;
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BUG_ON(!io);
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if (io->page)
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put_page(io->page);
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for (i = 0; i < io->num_io_pages; i++) {
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if (--io->pages[i]->p_count == 0) {
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struct page *page = io->pages[i]->p_page;
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end_page_writeback(page);
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put_page(page);
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kmem_cache_free(io_page_cachep, io->pages[i]);
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}
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}
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io->num_io_pages = 0;
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iput(io->inode);
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kmem_cache_free(io_end_cachep, io);
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}
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/*
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* check a range of space and convert unwritten extents to written.
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*/
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int ext4_end_io_nolock(ext4_io_end_t *io)
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{
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struct inode *inode = io->inode;
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loff_t offset = io->offset;
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ssize_t size = io->size;
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int ret = 0;
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ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p,"
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"list->prev 0x%p\n",
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io, inode->i_ino, io->list.next, io->list.prev);
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if (list_empty(&io->list))
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return ret;
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if (!(io->flag & EXT4_IO_END_UNWRITTEN))
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return ret;
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ret = ext4_convert_unwritten_extents(inode, offset, size);
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if (ret < 0) {
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printk(KERN_EMERG "%s: failed to convert unwritten "
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"extents to written extents, error is %d "
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"io is still on inode %lu aio dio list\n",
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__func__, ret, inode->i_ino);
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return ret;
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}
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if (io->iocb)
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aio_complete(io->iocb, io->result, 0);
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/* clear the DIO AIO unwritten flag */
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io->flag &= ~EXT4_IO_END_UNWRITTEN;
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return ret;
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}
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/*
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* work on completed aio dio IO, to convert unwritten extents to extents
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*/
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static void ext4_end_io_work(struct work_struct *work)
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{
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ext4_io_end_t *io = container_of(work, ext4_io_end_t, work);
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struct inode *inode = io->inode;
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struct ext4_inode_info *ei = EXT4_I(inode);
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unsigned long flags;
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int ret;
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mutex_lock(&inode->i_mutex);
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ret = ext4_end_io_nolock(io);
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if (ret < 0) {
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mutex_unlock(&inode->i_mutex);
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return;
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}
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spin_lock_irqsave(&ei->i_completed_io_lock, flags);
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if (!list_empty(&io->list))
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list_del_init(&io->list);
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spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
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mutex_unlock(&inode->i_mutex);
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ext4_free_io_end(io);
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}
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ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags)
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{
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ext4_io_end_t *io = NULL;
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io = kmem_cache_alloc(io_end_cachep, flags);
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if (io) {
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memset(io, 0, sizeof(*io));
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io->inode = igrab(inode);
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BUG_ON(!io->inode);
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INIT_WORK(&io->work, ext4_end_io_work);
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INIT_LIST_HEAD(&io->list);
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}
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return io;
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}
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/*
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* Print an buffer I/O error compatible with the fs/buffer.c. This
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* provides compatibility with dmesg scrapers that look for a specific
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* buffer I/O error message. We really need a unified error reporting
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* structure to userspace ala Digital Unix's uerf system, but it's
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* probably not going to happen in my lifetime, due to LKML politics...
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*/
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static void buffer_io_error(struct buffer_head *bh)
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{
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char b[BDEVNAME_SIZE];
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printk(KERN_ERR "Buffer I/O error on device %s, logical block %llu\n",
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bdevname(bh->b_bdev, b),
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(unsigned long long)bh->b_blocknr);
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}
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static void ext4_end_bio(struct bio *bio, int error)
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{
|
||||
ext4_io_end_t *io_end = bio->bi_private;
|
||||
struct workqueue_struct *wq;
|
||||
struct inode *inode;
|
||||
unsigned long flags;
|
||||
ext4_fsblk_t err_block;
|
||||
int i;
|
||||
|
||||
BUG_ON(!io_end);
|
||||
inode = io_end->inode;
|
||||
bio->bi_private = NULL;
|
||||
bio->bi_end_io = NULL;
|
||||
if (test_bit(BIO_UPTODATE, &bio->bi_flags))
|
||||
error = 0;
|
||||
err_block = bio->bi_sector >> (inode->i_blkbits - 9);
|
||||
bio_put(bio);
|
||||
|
||||
if (!(inode->i_sb->s_flags & MS_ACTIVE)) {
|
||||
pr_err("sb umounted, discard end_io request for inode %lu\n",
|
||||
io_end->inode->i_ino);
|
||||
ext4_free_io_end(io_end);
|
||||
return;
|
||||
}
|
||||
|
||||
if (error) {
|
||||
io_end->flag |= EXT4_IO_END_ERROR;
|
||||
ext4_warning(inode->i_sb, "I/O error writing to inode %lu "
|
||||
"(offset %llu size %ld starting block %llu)",
|
||||
inode->i_ino,
|
||||
(unsigned long long) io_end->offset,
|
||||
(long) io_end->size,
|
||||
(unsigned long long) err_block);
|
||||
}
|
||||
|
||||
for (i = 0; i < io_end->num_io_pages; i++) {
|
||||
struct page *page = io_end->pages[i]->p_page;
|
||||
struct buffer_head *bh, *head;
|
||||
int partial_write = 0;
|
||||
|
||||
head = page_buffers(page);
|
||||
if (error)
|
||||
SetPageError(page);
|
||||
BUG_ON(!head);
|
||||
if (head->b_size == PAGE_CACHE_SIZE)
|
||||
clear_buffer_dirty(head);
|
||||
else {
|
||||
loff_t offset;
|
||||
loff_t io_end_offset = io_end->offset + io_end->size;
|
||||
|
||||
offset = (sector_t) page->index << PAGE_CACHE_SHIFT;
|
||||
bh = head;
|
||||
do {
|
||||
if ((offset >= io_end->offset) &&
|
||||
(offset+bh->b_size <= io_end_offset)) {
|
||||
if (error)
|
||||
buffer_io_error(bh);
|
||||
|
||||
clear_buffer_dirty(bh);
|
||||
}
|
||||
if (buffer_delay(bh))
|
||||
partial_write = 1;
|
||||
else if (!buffer_mapped(bh))
|
||||
clear_buffer_dirty(bh);
|
||||
else if (buffer_dirty(bh))
|
||||
partial_write = 1;
|
||||
offset += bh->b_size;
|
||||
bh = bh->b_this_page;
|
||||
} while (bh != head);
|
||||
}
|
||||
|
||||
if (--io_end->pages[i]->p_count == 0) {
|
||||
struct page *page = io_end->pages[i]->p_page;
|
||||
|
||||
end_page_writeback(page);
|
||||
put_page(page);
|
||||
kmem_cache_free(io_page_cachep, io_end->pages[i]);
|
||||
}
|
||||
|
||||
/*
|
||||
* If this is a partial write which happened to make
|
||||
* all buffers uptodate then we can optimize away a
|
||||
* bogus readpage() for the next read(). Here we
|
||||
* 'discover' whether the page went uptodate as a
|
||||
* result of this (potentially partial) write.
|
||||
*/
|
||||
if (!partial_write)
|
||||
SetPageUptodate(page);
|
||||
}
|
||||
|
||||
io_end->num_io_pages = 0;
|
||||
|
||||
/* Add the io_end to per-inode completed io list*/
|
||||
spin_lock_irqsave(&EXT4_I(inode)->i_completed_io_lock, flags);
|
||||
list_add_tail(&io_end->list, &EXT4_I(inode)->i_completed_io_list);
|
||||
spin_unlock_irqrestore(&EXT4_I(inode)->i_completed_io_lock, flags);
|
||||
|
||||
wq = EXT4_SB(inode->i_sb)->dio_unwritten_wq;
|
||||
/* queue the work to convert unwritten extents to written */
|
||||
queue_work(wq, &io_end->work);
|
||||
}
|
||||
|
||||
void ext4_io_submit(struct ext4_io_submit *io)
|
||||
{
|
||||
struct bio *bio = io->io_bio;
|
||||
|
||||
if (bio) {
|
||||
bio_get(io->io_bio);
|
||||
submit_bio(io->io_op, io->io_bio);
|
||||
BUG_ON(bio_flagged(io->io_bio, BIO_EOPNOTSUPP));
|
||||
bio_put(io->io_bio);
|
||||
}
|
||||
io->io_bio = 0;
|
||||
io->io_op = 0;
|
||||
io->io_end = 0;
|
||||
}
|
||||
|
||||
static int io_submit_init(struct ext4_io_submit *io,
|
||||
struct inode *inode,
|
||||
struct writeback_control *wbc,
|
||||
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;
|
||||
do {
|
||||
bio = bio_alloc(GFP_NOIO, nvecs);
|
||||
nvecs >>= 1;
|
||||
} while (bio == NULL);
|
||||
|
||||
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->inode = inode;
|
||||
io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh);
|
||||
|
||||
io->io_bio = bio;
|
||||
io->io_op = (wbc->sync_mode == WB_SYNC_ALL ?
|
||||
WRITE_SYNC_PLUG : WRITE);
|
||||
io->io_next_block = bh->b_blocknr;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int io_submit_add_bh(struct ext4_io_submit *io,
|
||||
struct ext4_io_page *io_page,
|
||||
struct inode *inode,
|
||||
struct writeback_control *wbc,
|
||||
struct buffer_head *bh)
|
||||
{
|
||||
ext4_io_end_t *io_end;
|
||||
int ret;
|
||||
|
||||
if (buffer_new(bh)) {
|
||||
clear_buffer_new(bh);
|
||||
unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
|
||||
}
|
||||
|
||||
if (!buffer_mapped(bh) || buffer_delay(bh)) {
|
||||
if (!buffer_mapped(bh))
|
||||
clear_buffer_dirty(bh);
|
||||
if (io->io_bio)
|
||||
ext4_io_submit(io);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (io->io_bio && bh->b_blocknr != io->io_next_block) {
|
||||
submit_and_retry:
|
||||
ext4_io_submit(io);
|
||||
}
|
||||
if (io->io_bio == NULL) {
|
||||
ret = io_submit_init(io, inode, wbc, bh);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
io_end = io->io_end;
|
||||
if ((io_end->num_io_pages >= MAX_IO_PAGES) &&
|
||||
(io_end->pages[io_end->num_io_pages-1] != io_page))
|
||||
goto submit_and_retry;
|
||||
if (buffer_uninit(bh))
|
||||
io->io_end->flag |= EXT4_IO_END_UNWRITTEN;
|
||||
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;
|
||||
if ((io_end->num_io_pages == 0) ||
|
||||
(io_end->pages[io_end->num_io_pages-1] != io_page)) {
|
||||
io_end->pages[io_end->num_io_pages++] = io_page;
|
||||
io_page->p_count++;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
int ext4_bio_write_page(struct ext4_io_submit *io,
|
||||
struct page *page,
|
||||
int len,
|
||||
struct writeback_control *wbc)
|
||||
{
|
||||
struct inode *inode = page->mapping->host;
|
||||
unsigned block_start, block_end, blocksize;
|
||||
struct ext4_io_page *io_page;
|
||||
struct buffer_head *bh, *head;
|
||||
int ret = 0;
|
||||
|
||||
blocksize = 1 << inode->i_blkbits;
|
||||
|
||||
BUG_ON(PageWriteback(page));
|
||||
set_page_writeback(page);
|
||||
ClearPageError(page);
|
||||
|
||||
io_page = kmem_cache_alloc(io_page_cachep, GFP_NOFS);
|
||||
if (!io_page) {
|
||||
set_page_dirty(page);
|
||||
unlock_page(page);
|
||||
return -ENOMEM;
|
||||
}
|
||||
io_page->p_page = page;
|
||||
io_page->p_count = 0;
|
||||
get_page(page);
|
||||
|
||||
for (bh = head = page_buffers(page), block_start = 0;
|
||||
bh != head || !block_start;
|
||||
block_start = block_end, bh = bh->b_this_page) {
|
||||
block_end = block_start + blocksize;
|
||||
if (block_start >= len) {
|
||||
clear_buffer_dirty(bh);
|
||||
set_buffer_uptodate(bh);
|
||||
continue;
|
||||
}
|
||||
ret = io_submit_add_bh(io, io_page, inode, wbc, bh);
|
||||
if (ret) {
|
||||
/*
|
||||
* We only get here on ENOMEM. Not much else
|
||||
* we can do but mark the page as dirty, and
|
||||
* better luck next time.
|
||||
*/
|
||||
set_page_dirty(page);
|
||||
break;
|
||||
}
|
||||
}
|
||||
unlock_page(page);
|
||||
/*
|
||||
* If the page was truncated before we could do the writeback,
|
||||
* or we had a memory allocation error while trying to write
|
||||
* the first buffer head, we won't have submitted any pages for
|
||||
* I/O. In that case we need to make sure we've cleared the
|
||||
* PageWriteback bit from the page to prevent the system from
|
||||
* wedging later on.
|
||||
*/
|
||||
if (io_page->p_count == 0) {
|
||||
put_page(page);
|
||||
end_page_writeback(page);
|
||||
kmem_cache_free(io_page_cachep, io_page);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
|
@ -4769,9 +4769,12 @@ static int __init init_ext4_fs(void)
|
|||
int err;
|
||||
|
||||
ext4_check_flag_values();
|
||||
err = init_ext4_system_zone();
|
||||
err = init_ext4_pageio();
|
||||
if (err)
|
||||
return err;
|
||||
err = init_ext4_system_zone();
|
||||
if (err)
|
||||
goto out5;
|
||||
ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
|
||||
if (!ext4_kset)
|
||||
goto out4;
|
||||
|
|
@ -4812,6 +4815,8 @@ out3:
|
|||
kset_unregister(ext4_kset);
|
||||
out4:
|
||||
exit_ext4_system_zone();
|
||||
out5:
|
||||
exit_ext4_pageio();
|
||||
return err;
|
||||
}
|
||||
|
||||
|
|
@ -4827,6 +4832,7 @@ static void __exit exit_ext4_fs(void)
|
|||
remove_proc_entry("fs/ext4", NULL);
|
||||
kset_unregister(ext4_kset);
|
||||
exit_ext4_system_zone();
|
||||
exit_ext4_pageio();
|
||||
}
|
||||
|
||||
MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
|
||||
|
|
|
|||
Loading…
Reference in a new issue